CN117128229B

CN117128229B - Folding mechanism and foldable electronic equipment

Info

Publication number: CN117128229B
Application number: CN202310140782.8A
Authority: CN
Inventors: 孟刚; 董绍洪; 陈瑞豪; 金开放
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2023-02-14
Filing date: 2023-02-14
Publication date: 2024-07-05
Anticipated expiration: 2043-02-14
Also published as: CN117128229A

Abstract

The application discloses a folding mechanism and foldable electronic equipment, and belongs to the technical field of electronic equipment. The folding mechanism comprises: the folding device comprises a base, a folding assembly and a flexible constant force mechanism, wherein the base extends along a first direction; the folding assembly comprises at least one swing arm group, each swing arm group comprises a first swing arm and a second swing arm which are respectively positioned at two sides of the base, and the first swing arm and the second swing arm are respectively connected with the base in a rotating way; the first swing arm and/or the second swing arm compress the flexible constant force mechanism when rotating, and the flexible constant force mechanism outputs constant force to the first swing arm and/or the second swing arm when the rotating angle of the first swing arm and/or the second swing arm is in a first angle range. The folding mechanism solves the problem that the damping force is reduced due to structural abrasion to a certain extent, so that the folding mechanism is stronger in opening and closing stability.

Description

Folding mechanism and foldable electronic equipment

Technical Field

The present application relates to the field of electronic devices, and in particular, to a folding mechanism and a foldable electronic device.

Background

In recent years, technology of electronic devices is updated faster, and the foldable electronic devices are popular with users because they can have a larger display area and better portability.

Current foldable electronic devices typically include a flexible screen and a folding mechanism for switching the flexible screen between a folded state and an unfolded state. In order to maintain the opening and closing hand feeling in the rotating process and simultaneously have the opening and closing maintaining force (folding state maintaining force and unfolding state maintaining force), a damping mechanism is required to be arranged in the folding mechanism. The damping mechanism comprises a swing arm, a cam assembly and a spring, wherein the cam assembly comprises two cams, one cam is installed on the swing arm, the other cam is connected with the spring, and the two cams are coaxially arranged relatively. In the folding mechanism opening and closing process, the swing arm drives the cam connected with the swing arm to rotate, and the cam rotates to push the cam connected with the spring to move along the axial direction of the cam, so that the spring is compressed, the spring is compressed to generate damping moment, the folding mechanism generates damping force, the opening and closing hand feeling is improved, and the opening and closing holding force is provided.

However, as friction is generated between the two cams in the rotation overshoot process, relatively large abrasion is generated after the service time is long, so that the compression amount of the spring is reduced, the opening and closing hand feeling is further influenced, and the opening and closing retaining force is further influenced.

Disclosure of Invention

The application provides a folding mechanism and foldable electronic equipment, wherein the folding mechanism can keep the opening and closing hand feeling and the opening and closing holding force constant.

The technical scheme is as follows:

a first aspect of the present application provides a folding mechanism comprising:

a base extending in a first direction;

the folding assembly comprises at least one swing arm group, each swing arm group comprises a first swing arm and a second swing arm which are respectively positioned at two sides of the base, and the first swing arm and the second swing arm are respectively connected with the base in a rotating way;

The flexible constant force mechanism compresses the flexible constant force mechanism when the first swing arm and/or the second swing arm rotate, and the flexible constant force mechanism outputs constant force to the first swing arm and/or the second swing arm when the rotation angle of the first swing arm and/or the second swing arm is in a first angle range.

The folding mechanism provided by the application has the beneficial effects that at least: in the folding mechanism opening and closing process, the first swing arm and the second swing arm rotate relative to the base respectively, at least one of the first swing arm and the second swing arm compresses the flexible constant force mechanism, the flexible constant force mechanism is compressed to generate a reaction force, and the reaction force is transmitted to the first swing arm and/or the second swing arm, so that the folding mechanism has damping force in the opening and closing process, and the hand feeling of the folding mechanism in the opening and closing process is improved. Since a constant reaction force is output when the rotation angle of the first swing arm and/or the second swing arm is within a first angle range, the reaction force acts on the first swing arm and/or the second swing arm compressing the same, that is, a damping force is provided for the folding mechanism. Therefore, on one hand, in the opening and closing process, the flexible constant force mechanism outputs constant force so that the damping force is constant, and the opening and closing hand feeling is good; on the other hand, even after any one of the first swing arm and/or the second swing arm, the transmission structure and the flexible constant force mechanism is worn, the reaction force provided by the flexible constant force mechanism is unchanged, namely the folding mechanism cannot reduce the damping force due to structural wear, so that the folding mechanism has stronger opening and closing holding stability.

In some implementations, the compliant constant force mechanism includes a positive stiffness structure and a bi-stable structure, the positive stiffness structure being coupled to the bi-stable structure, the reaction force generated by the positive stiffness structure increasing with an increase in the compression of the compliant constant force mechanism, the reaction force generated by the bi-stable structure generating a periodic variation with an increase in the compression of the compliant constant force mechanism; at least when the rotation angle of the first swing arm and/or the second swing arm is in a first angle range, the resultant force of the positive stiffness structure and the bistable structure is a fixed value.

In some implementations, the number of positive stiffness structures and the number of bistable structures are each one, the positive stiffness structures and the bistable structures being disposed sequentially along the first direction.

In some implementations, the number of positive stiffness structures is one, the number of bistable structures is two, two bistable structures are located on two sides of the positive stiffness structures respectively along the first direction, and the positive stiffness structures are connected with the two bistable structures respectively.

In some implementations, the number of positive stiffness structures and the number of bistable structures are each a plurality, the plurality of positive stiffness structures and the plurality of bistable structures being alternately arranged along the first direction.

In some implementations, the positive stiffness structure and the bi-stable structure are connected to enclose a cylindrical structure.

In some implementations, the bistable structure includes a first flexible beam, a second flexible beam, and first, second, and third rigid blocks extending along a first direction, the second and third rigid blocks being located on either side of the first rigid block, respectively, in a second direction, the first direction being perpendicular to the second direction, at least one first flexible beam being disposed between the second and first rigid blocks, at least one second flexible beam being disposed between the third and first rigid blocks, both the first and second flexible beams being disposed oblique to the first direction, the first and second flexible beams being disposed symmetrically with respect to the first rigid block.

In some implementations, the number of bistable structures is two, the two first rigid blocks are arranged at intervals along the first direction, the two second rigid blocks are integrated, the two third rigid blocks are integrated, and two ends of the positive rigid structure are respectively connected with the two first rigid blocks.

In some implementations, the positive stiffness structure includes a bending member, the bending member includes a third flexible beam and a connecting beam, the number of the third flexible beams is plural, the plural third flexible beams are disposed at intervals along the first direction, and each third flexible beam is disposed parallel to the second direction, the plural third flexible beams are sequentially connected by the connecting beam in an anti-series manner, and the third flexible beam located at the edge is connected with the first rigid block.

In some implementations, the connection beam is a flexible straight beam, the connection beam being disposed parallel to the first direction.

In some implementations, the connection beam is an arc beam.

In some implementations, the positive stiffness structure includes a third flexible beam disposed parallel to the second direction, the third flexible beam disposed between the first and second rigid blocks, and between the first and third rigid blocks.

In some implementations, the positive stiffness structure includes a third flexible beam, the third flexible beam is disposed between the first rigid block and the second rigid block, between the first rigid block and the third rigid block, the third flexible beam includes a first section, a second section, and a third section, the first section and the second section are all parallel to the second direction, the third section is parallel to the first direction, the first section is connected with the first rigid block, the first section and the third section are connected through the second section, and the third section is connected with the second rigid block or the third rigid block.

In some implementations, the positive stiffness structure includes a third flexible beam and a connecting beam, the two first rigid blocks are connected with the third flexible beam, the third flexible beams connected with the two first rigid blocks are symmetrically arranged, the symmetrical two third flexible beams are connected through the connecting beam, and each third flexible beam is inclined to the first direction.

In some implementations, the folding mechanism further includes a drive assembly including a first drive structure and a second drive structure, the first drive structure is disposed in the first swing arm and/or the second swing arm, the second drive structure is disposed in the compliant constant force mechanism, the first drive structure is in drive connection with the second drive structure, and the first drive structure moves to drive the second drive structure to move in the first direction.

In some implementations, the first transmission structure includes a first cam structure, the second transmission structure includes a second cam structure, the first cam structure contacts the second cam structure, and rotation of the first cam structure moves the second cam structure in the first direction.

In some implementations, the folding mechanism further includes a positioning shaft, the first cam structure is provided with a first through hole along the first direction, the second cam structure is provided with a second through hole along the first direction, and the positioning shaft sequentially penetrates through the first through hole and the second through hole.

In some implementations, the first swing arm is provided with two first transmission structures at intervals along the first direction, the second swing arm is provided with two first transmission structures at intervals along the first direction, the compliant constant force mechanism is provided with four second transmission structures, and the four second transmission structures are in one-to-one transmission connection with the four first transmission structures.

In some implementations, the folding mechanism further includes a connection mechanism rotatably connected with the base;

The first swing arm is connected with the connecting mechanism in a sliding manner along the second direction, and the flexible constant force mechanism is arranged on the connecting mechanism; and/or the second swing arm is connected with the connecting mechanism in a sliding way along the second direction, and the flexible constant force mechanism is arranged on the connecting mechanism;

the second direction is perpendicular to the first direction.

In some implementations, one of the first and second drive structures includes a slider, the other includes a chute, the chute is an arcuate slot, and the slider is slidingly assembled with the chute.

In some implementations, the folding mechanism further includes a connection mechanism (500), the connection mechanism (500) being rotatably connected with the base (110); the connecting mechanism is provided with a guide groove, and the sliding block passes through the guide groove and then contacts with the sliding groove.

In some implementations, one of the first and second drive structures includes a ramp disposed obliquely relative to the second direction, the second direction being perpendicular to the first direction.

In some implementations, the other of the first and second drive structures includes a bump having an arcuate surface that contacts the bevel.

The second aspect of the present application provides a foldable electronic device, including a first housing, a second housing, a display screen, and a folding mechanism according to any one of the above embodiments, where the folding mechanism is connected between the first housing and the second housing, the display screen is mounted on the first housing, the second housing, and the folding mechanism, and when a swing arm set in the folding mechanism rotates, the first housing and the second housing relatively rotate, so as to drive the display screen to bend or unfold.

By means of the technical scheme, the electronic equipment comprises the folding mechanism, so that the electronic equipment at least has all beneficial effects of the folding mechanism, and the detailed description is omitted.

Drawings

Fig. 1 is a schematic structural diagram of a foldable electronic device in a first state according to an embodiment of the present application;

Fig. 2 is a schematic structural diagram of a foldable electronic device in a second state according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a foldable electronic device in a third state according to an embodiment of the present application;

FIG. 4 is a schematic diagram of an exploded structure of the foldable electronic device of FIG. 3;

FIG. 5 is a schematic structural view of a folding mechanism according to an embodiment of the present application;

FIG. 6 is a schematic view of a part of a folding mechanism according to an embodiment of the present application;

FIG. 7 is a schematic view of a folding mechanism according to an embodiment of the present application in an unfolded state;

FIG. 8 is a schematic view of a folding mechanism according to an embodiment of the present application in a folded state;

FIG. 9 is a schematic diagram of the relationship between the amount of compression and the reaction force of a positive stiffness structure according to an embodiment of the present application;

FIG. 10 is a schematic diagram of the compression versus reaction force for another positive stiffness structure provided by an embodiment of the present application;

FIG. 11 is a graph showing the relationship between the compression and the reaction force of a bistable structure according to an embodiment of the application;

FIG. 12 is a schematic diagram showing the relationship between the compression amount and the reaction force of a folding mechanism according to an embodiment of the present application;

FIG. 13 is a partial schematic view of the relationship between the compression and the reaction force of a folding mechanism according to an embodiment of the present application;

FIG. 14 is a schematic diagram showing the assembly of a compliant constant force mechanism, a first swing arm, and a second swing arm according to an embodiment of the present application;

FIG. 15 is a schematic structural view of a first compliant constant force mechanism according to an embodiment of the present application;

FIG. 16 is a schematic diagram II of a first compliant constant force mechanism according to an embodiment of the present application;

FIG. 17 is a schematic diagram of a second compliant constant force mechanism according to an embodiment of the present application;

FIG. 18 is a schematic structural view of a third compliant constant force mechanism provided by an embodiment of the present application;

FIG. 19 is a schematic diagram of a fourth compliant constant force mechanism provided by an embodiment of the present application;

FIG. 20 is a schematic structural view of a fifth compliant constant force mechanism provided by an embodiment of the present application;

FIG. 21 is a schematic view of another folding mechanism according to an embodiment of the present application;

FIG. 22 is a schematic view showing a part of another folding mechanism according to the embodiment of the present application;

FIG. 23 is a schematic diagram showing a part of another folding mechanism according to the second embodiment of the present application;

FIG. 24 is a schematic view of a compliant constant force mechanism in another folding mechanism provided by an embodiment of the present application;

FIG. 25 is a schematic view of a folding mechanism according to an embodiment of the present application;

FIG. 26 is a schematic view of a part of a folding mechanism according to an embodiment of the present application;

FIG. 27 is a schematic view of a compliant constant force mechanism in yet another folding mechanism provided in accordance with an embodiment of the present application;

FIG. 28 is a schematic view of a second swing arm of yet another folding mechanism according to an embodiment of the present application;

FIG. 29 is a schematic view of a part of a folding mechanism according to an embodiment of the present application;

FIG. 30 is a schematic view of a compliant constant force mechanism in yet another folding mechanism according to an embodiment of the present application.

Wherein, the meanings represented by the reference numerals are respectively as follows:

100. a folding mechanism; 110. a base;

211. a first swing arm; 212. a second swing arm; 220. positioning a shaft;

300. A compliant constant force mechanism; 310. a positive stiffness structure; 311. a third flexible beam; 3111. a first section; 3112. a second section; 3113. a third section; 312. a connecting beam; 320. a bistable structure; 321. a first flexible beam; 322. a second flexible beam; 323. a first rigid block; 324. a second rigid block; 325. a third rigid block;

410. A first transmission structure; 411. a first cam structure; 412. a chute; 413. an inclined plane; 420. a second transmission structure; 421. a second cam structure; 422. a slide block; 423. a bump; 4231. an arc surface;

500. A connecting mechanism; 510. a guide groove;

600. A synchronization structure;

710. A first door panel; 711. a first door panel swing arm; 720. a second door panel; 721. a second door panel swing arm; 730. a display screen; 731. a first portion; 732. a second portion; 733. a foldable portion; 741. a first housing; 742. and a second housing.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

It should be understood that references to "a plurality" in this disclosure refer to two or more. In the description of the present application, "/" means or, unless otherwise indicated, for example, A/B may represent A or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, in order to facilitate the clear description of the technical solution of the present application, the words "first", "second", etc. are used to distinguish the same item or similar items having substantially the same function and function. It will be appreciated by those of skill in the art that the words "first," "second," and the like do not limit the amount and order of execution, and that the words "first," "second," and the like do not necessarily differ.

The folding mechanism and the electronic device provided by the embodiment of the application are explained in detail below.

Referring to fig. 1 to 3, fig. 1 is a schematic structural diagram of a foldable electronic device in a first state, fig. 2 is a schematic structural diagram of a foldable electronic device in a second state, and fig. 3 is a schematic structural diagram of a foldable electronic device in a third state, according to an embodiment of the present application.

For convenience of description, a width direction of the foldable electronic device is defined as a B-B direction, a length direction of the foldable electronic device is defined as an A-A direction, and a thickness direction of the foldable electronic device is defined as a C-C direction. The A-A direction, the B-B direction and the C-C direction are perpendicular to each other.

Foldable electronic devices include, but are not limited to, cell phones (cellphone), notebook computers (notebook computer), tablet computers (tablet personal computer), laptop computers (laptop computers), personal digital assistants (personal DIGITAL ASSISTANT), wearable devices (wearable devices), or vehicle devices (mobile devices), among others. In the embodiment of the application, a foldable electronic device is taken as an example of a mobile phone.

The foldable electronic device shown in fig. 1 is in a folded state, the foldable electronic device shown in fig. 2 is in a semi-unfolded state, and the foldable electronic device shown in fig. 3 is in an unfolded state. The unfolding angle α of the foldable electronic device shown in fig. 2 is 90 degrees, and the unfolding angle β of the foldable electronic device shown in fig. 3 is 180 degrees.

It should be noted that the angles illustrated in the embodiments of the present application allow for a few deviations. For example, the angle α of expansion of the foldable electronic device shown in fig. 2 is 90 degrees, which means that α may be 90 degrees, or may be about 90 degrees, such as 80 degrees, 85 degrees, 95 degrees, or 100 degrees. The angle β of the foldable electronic device shown in fig. 3 is 180 degrees, which means that β may be 180 degrees, or may be about 180 degrees, such as 170 degrees, 175 degrees, 185 degrees, 190 degrees, etc. The angles illustrated hereinafter are to be understood identically.

The foldable electronic device in the embodiment of the application is an electronic device capable of being folded once. In other embodiments, the foldable electronic device may also be an electronic device that may be folded multiple times (more than twice). At this time, the foldable electronic device may include a plurality of portions, and two adjacent portions may be relatively close to be folded to the foldable electronic device in a folded state, and two adjacent portions may be relatively far away from be unfolded to the foldable electronic device in an unfolded state.

Referring to fig. 4, fig. 4 is an exploded view of the foldable electronic device shown in fig. 3. The foldable electronic device includes a first housing 741, a second housing 742, a folding mechanism 100, and a display 730, the first housing 741 and the second housing 742 are respectively mounted to both sides of the folding mechanism 100 in the B-B direction, and the first housing 741 and the second housing 742 are relatively rotated by the folding mechanism 100. The display screen 730 is mounted to the first housing 741, the second housing 742 and the folding mechanism 100, and the display screen 730 includes a first portion 731, a second portion 732 and a foldable portion 733. The foldable portion 733 is located between the first portion 731 and the second portion 732, and the foldable portion 733 may be bent in the A-A direction. The first portion 731, the second portion 732, and the foldable portion 733 together comprise the display 730. In this embodiment, the display screen 730 is a flexible display screen, for example, an organic light-emitting diode (OLED) display screen, an active-matrix organic light-emitting diode (OLED) or active-matrix organic light-emitting diode (AMOLED) display screen, a mini light-emitting diode (mini organic lightemitting diode) display screen, a micro light-emitting diode (micro organic light-emitting diode) display screen, a micro organic light-emitting diode (micro organic light-emitting diode) display screen, and a quantum dot light-emitting diode (qded) display screen.

The display 730 is folded by the relative proximity of the first housing 741 and the second housing 742 so that the foldable electronic device is folded. When the foldable electronic device is in the folded state, the foldable portion 330 of the display screen 730 is bent, and the first portion 731 and the second portion 732 are disposed opposite to each other. At this time, the display screen 730 is located between the first housing 741 and the second housing 742, so that the probability of damaging the display screen 730 can be greatly reduced, and effective protection of the display screen 730 can be achieved.

Referring to fig. 2 and fig. 4 together, the first housing 741 and the second housing 742 rotate relatively through the folding mechanism 100, and the display 730 is unfolded by moving the first housing 741 and the second housing 742 relatively away from each other, so that the foldable electronic device is unfolded to a half-unfolded state. When the foldable electronic device is in the semi-unfolded state, the first housing 741 and the second housing 742 are unfolded to have an included angle α, and the first portion 731 and the second portion 732 are relatively unfolded and drive the foldable portion 733 to be unfolded. At this time, the angle between the first portion 731 and the second portion 732 is α.

Referring to fig. 3 and fig. 4 together, the first housing 741 and the second housing 742 rotate relatively through the folding mechanism 100, and the display 730 is further unfolded by moving the first housing 741 and the second housing 742 relatively away from each other until the foldable electronic device is unfolded. When the folding apparatus 200 is in the flattened state, the angle between the first housing 741 and the second housing 742 is β. The foldable portion 733 is unfolded and the first portion 731 and the second portion 732 are relatively unfolded. At this time, the included angles between the first portion 731, the second portion 732, and the foldable portion 733 are all β, and the display screen 730 has a large-area display area, so as to realize large-screen display of the foldable electronic device, and improve the use experience of the user.

It should be noted that, the included angle α and the included angle β are included angles between the first housing 741 and the second housing 742, which are only used to distinguish the angle between the first housing 741 and the second housing 742 of the foldable electronic device in different states. Wherein the included angle α is an angle between the first housing 741 and the second housing 742 when the foldable electronic device is in the semi-unfolded state; the angle β is an angle between the first housing 741 and the second housing 742 in the unfolded state of the foldable electronic device.

Referring to fig. 5 to 8, an embodiment of the present application provides a folding mechanism applicable to the foldable electronic device, including: base 110, folding assembly, and compliant constant force mechanism 300, base 110 extending in a first direction (A-A direction); the folding assembly comprises at least one swing arm group, each swing arm group comprises a first swing arm 211 and a second swing arm 212 which are respectively positioned at two sides of the base 110, and the first swing arm 211 and the second swing arm 212 are respectively connected with the base 110 in a rotating way; the compliant constant force mechanism 300 is compressed when the first swing arm 211 and/or the second swing arm 212 rotates, and the compliant constant force mechanism 300 outputs a constant force when the rotation angle of the first swing arm 211 and/or the second swing arm 212 is within the first angular range. The folding mechanism includes a folded state and an unfolded state, and when the folding mechanism is rotated to the unfolded state via the folded state and from the unfolded state to the folded state, the first swing arm 211 and the second swing arm 212 are respectively rotated, and the first angle range includes at least an angle range in which the first swing arm 211 is rotated when switching between the folded state and the unfolded state, and an angle range in which the second swing arm 212 is rotated when switching between the folded state and the unfolded state. That is, the compliant constant force mechanism 300 applies a constant force to the first swing arm 211 and/or the second swing arm 212 of the swing arm set for compressing the compliant constant force mechanism at least during the switching of the folding mechanism between the unfolded state and the folded state.

The base 110 is used for mounting a folding assembly or the like, and the base 110 extends in a first direction (A-A direction), that is, a length direction of the base 110 is parallel to the first direction (A-A direction). The outer contour shape of the base 110 may be a rectangular parallelepiped shape or a cuboid-like shape.

The folding assembly includes at least one swing arm set, where the swing arm set includes a first swing arm 211 and a second swing arm 212, the first swing arm 211 and the second swing arm 212 are located at two sides of the base 110 respectively, that is, if a plane parallel to a thickness direction (C-C direction) of the base 110 and passing through a central axis parallel to the first direction (A-A direction) is taken as a reference plane W, one end of the first swing arm 211 is rotationally connected with the base 110, at least a part of the other end is located at one side of the reference plane W, one end of the second swing arm 212 is rotationally connected with the base 110, and at least a part of the other end is located at the other side of the reference plane W. During the folding or unfolding of the folding mechanism, the rotation directions of the first swing arm 211 and the second swing arm 212 are opposite. The folding assembly may include a plurality of swing arm groups, which may be spaced apart on the base 110 along a first direction (A-A direction), each of the first swing arms 211 being located at one side of the reference plane W, and the rotation directions of the first swing arms 211 being the same; each second swing arm 212 is located at the other side of the reference plane, and the rotation directions of the second swing arms 212 are the same.

The first swing arm 211 and/or the second swing arm 212 compress the compliant constant force mechanism 300 during rotation, that is, only one compliant constant force mechanism 300 may be provided corresponding to the first swing arm 211, and the first swing arm 211 compresses the compliant constant force mechanism 300 during folding or unfolding of the folding assembly; or only one flexible constant force mechanism 300 can be arranged corresponding to the second swing arm 212, and the second swing arm 212 enables the flexible constant force mechanism 300 to be compressed in the folding or unfolding process of the folding assembly; or the first swing arm 211 and the second swing arm 212 can be arranged opposite to the same flexible constant force mechanism 300, and in the folding or unfolding process of the folding assembly, the first swing arm 211 and the second swing arm 212 both act on the same flexible constant force mechanism 300 and compress the flexible constant force mechanism 300; or one flexible constant force mechanism 300 is arranged corresponding to the first swing arm 211, the other flexible constant force mechanism 300 is arranged corresponding to the second swing arm 212, in the folding or unfolding process of the folding mechanism, the first swing arm 211 rotates to enable the flexible constant force mechanism 300 arranged opposite to the first swing arm to compress, the second swing arm 212 rotates to enable the flexible constant force mechanism 300 arranged opposite to the second swing arm to compress, and the two flexible constant force mechanisms 300 jointly enable the folding assembly to generate damping force. When the number of swing arm groups is plural, the compliant constant force mechanism 300 may be disposed between adjacent swing arm groups, for example, between two adjacent first swing arms 211, and during folding or unfolding of the folding mechanism, both first swing arms 211 compress the compliant constant force mechanism 300; or between two adjacent second swing arms 212, both second swing arms 212 compress the compliant constant force mechanism 300 during folding or unfolding of the folding mechanism; or a flexible constant force mechanism 300 is respectively arranged between the two first swing arms 211 and between the two second swing arms 212, and the two first swing arms 211 and the two second swing arms 212 respectively compress the corresponding flexible constant force mechanism 300 in the folding or unfolding process of the folding mechanism; or only one flexible constant force mechanism 300 is arranged between the two first swing arms 211 and between the two second swing arms 212, and the two first swing arms 211 and the two second swing arms 212 enable the flexible constant force mechanism 300 to compress in the folding or unfolding process of the folding mechanism.

The folding mechanism provided by the embodiment is applied to folding electronic equipment, including but not limited to mobile phones, tablet computers, electronic books, smart watches and the like. The folding mechanism provided in the embodiment can be applied to an inward folding type electronic device or an outward folding type electronic device. The inward folding type electronic equipment is that the display screen is positioned at the inner side of the electronic equipment after being folded; the external folding type electronic equipment is that at least part of the display screen is positioned on the outer side of the electronic equipment after being folded.

The folding mechanism provided in this embodiment is configured such that, during the folding mechanism opening and closing process, the first swing arm 211 and the second swing arm 212 rotate in opposite directions with respect to the base 110, respectively, so as to switch between a folded state and an unfolded state. At least one of the first swing arm 211 and the second swing arm 212 compresses the compliant constant force mechanism 300, and the compliant constant force mechanism 300 generates a reaction force when being compressed, and the reaction force acts on the first swing arm 211 and/or the second swing arm 212 of the compressed compliant constant force mechanism 300, so that the folding mechanism has damping force in the opening and closing process, and the hand feeling of the folding mechanism in the opening and closing process is improved. Since the constant force is output when the rotation angle of the first swing arm 211 and/or the second swing arm 212 is within the first angle range, on one hand, in the opening and closing process, the damping force is constant due to the constant force output by the flexible constant force mechanism 300, and the opening and closing hand feeling is good; on the other hand, even after any one of the first swing arm 211 and/or the second swing arm 212, the transmission structure, and the compliant constant force mechanism 300 is worn, the reaction force provided by the compliant constant force mechanism 300 is unchanged, that is, the folding mechanism does not reduce the damping force due to structural wear, so that the folding mechanism has stronger folding holding stability.

In some implementations, the compliant constant force mechanism 300 includes a positive stiffness structure 310 and a bi-stable structure 320, the positive stiffness structure 310 being coupled to the bi-stable structure 320, the reaction force generated by the positive stiffness structure 310 increasing with an increase in the amount of compression of the compliant constant force mechanism 300, the reaction force generated by the bi-stable structure 320 generating a periodic variation with an increase in the amount of compression of the compliant constant force mechanism 300; at least when the rotation angle of the first swing arm 211 and/or the second swing arm 212 is within the first angle range, the resultant force of the positive stiffness structure 310 and the bistable structure 320 is constant.

Fig. 9 is a schematic diagram showing a relationship between the reaction force and the compression amount of the positive stiffness structure 310, wherein the reaction force provided by the positive stiffness structure 310 increases with increasing compression amount, the compression amount of the positive stiffness structure 310 is shown on the abscissa in fig. 9, the reaction force provided by the positive stiffness structure 310 is shown on the ordinate, and the slope is the stiffness of the positive stiffness structure 310. The stiffness of the positive stiffness structure 310 in fig. 9 is positive. The stiffness of the positive stiffness structure 310 may vary linearly or may vary in a curve, in which case the stiffness of the positive stiffness structure 310 varies linearly in fig. 9 and the stiffness of the positive stiffness structure 310 varies in a curve in fig. 10.

As shown in fig. 11, fig. 11 is a schematic diagram of the relationship between the reaction force and the compression amount of the bistable structure 320, in which the reaction force provided by the bistable structure 320 changes in a periodic fluctuation with increasing compression amount, the abscissa in fig. 11 is the compression amount of the bistable structure 320, the ordinate is the reaction force provided by the bistable structure 320, and the slope is the rigidity of the bistable structure 320. In fig. 11, the reaction force provided by the bistable structure 320 varies in a sinusoidal waveform with increasing compression, and the stiffness of the bistable structure 320 is positive in a partial interval and negative in a partial interval in one cycle.

By setting the precompression amount of the compliant constant force mechanism 300, the stiffness of the positive stiffness structure 310 is positive, the stiffness of the bistable structure 320 is negative, and the sum of the stiffness of the positive stiffness structure 310 and the stiffness of the bistable structure 320 is zero or approaches zero in the working state of the compliant constant force mechanism 300, so that the compliant constant force mechanism 300 has zero stiffness characteristic in the working state, that is, the reaction force output by the compliant constant force mechanism 300 is constant force. As shown in FIG. 12, the compliant constant force mechanism 300 stiffness is constant over a range of compression. It should be noted that the constant force in this embodiment includes a constant value and fluctuates within a very small range, and the influence of the range on the opening and closing hand feel during the use process is negligible, that is, the constant force includes a constant value and a small range of fluctuation values approaching the constant value.

The stiffness of the positive stiffness structure 310 and the stiffness of the bi-stable structure 320 may be adjusted by varying the dimensional data of the length, width, thickness, etc. of its own structure, the specific structural shape of the positive stiffness structure 310 and the bi-stable structure 320, or the number of positive stiffness structures 310 and the bi-stable structure 320, etc. such that the stiffness of the positive stiffness structure 310 and the stiffness of the bi-stable structure 320 are zero or near zero within a range of compression.

In a specific embodiment, the compliant constant force mechanism 300 needs to be pre-pressed in the assembly process, a relation diagram of the compression amount of the compliant constant force mechanism 300 and the reaction force output by the compliant constant force mechanism 300 is shown in fig. 13, S1 and S4 are respectively a start point and an end point of the constant force section output by the compliant constant force mechanism 300, a point S2 is an assembly pre-pressing point of the compliant constant force mechanism 300, S3 is a limit compression point of the compliant constant force mechanism 300, S2 is greater than or equal to S1, S2 is less than S3, and S3 is less than or equal to S4. When the compression amount is smaller than S2, the working interval is between the compression amounts S2 and S3, that is, the compliant constant force mechanism 300 is preloaded in the assembly process, so that the compliant constant force mechanism 300 is compressed at least to S2. When the compliant constant force mechanism 300 is in an operating state, the maximum compression amount is S3, and the minimum compression amount is S2. Between S2 and S3, the reaction force output by the compliant constant force mechanism 300 is a constant force.

As shown in fig. 13, in a specific embodiment, S2 is greater than S1, a reserved wear section is formed between S1 and S2, in this arrangement, after the folding mechanism is used for a long time, if the structure for compressing the compliant constant force mechanism 300 wears, the minimum compression amount of the compliant constant force mechanism 300 during the working section is reduced, that is, the S2 value is reduced, and when the S2 value is still in the range of greater than or equal to S1, the reaction force output by the compliant constant force mechanism 300 is still a constant force, that is, even if the structure for compressing the compliant constant force mechanism 300 wears, the output force of the compliant constant force mechanism 300 is not affected, and the stability of the opening and closing feel and the opening and closing state is not affected.

In one embodiment, as shown in fig. 13, the compliant constant force mechanism 300 retains a safe zone during assembly, S3 is less than S4, and a safe zone is between S3 and S4. Even if the compression amount of the flexible constant force mechanism 300 is larger than S3 due to unexpected situations, the flexible constant force mechanism 300 can be ensured to be normally used, namely, the material failure of the flexible constant force mechanism 300 due to overpressure can be avoided due to reserved safety intervals.

In one compliant constant force mechanism 300, the number of positive stiffness structures 310 is at least one and the number of bi-stable structures 320 is at least one in one compliant constant force mechanism 300. For example, in some embodiments, the number of positive stiffness structures 310 and bistable structures 320 are each one; or the number of positive stiffness structures 310 is one and the number of bi-stable structures 320 is a plurality; or the number of positive stiffness structures 310 is a plurality and the number of bistable structures 320 is one; or the number of positive stiffness structures 310 is a plurality and the number of bi-stable structures 320 is a plurality. When the number of positive stiffness structures 310 and bistable structures 320 are multiple, the number of positive stiffness structures 310 and bistable structures 320 may be the same or different.

As shown in fig. 14-20, in some implementations, one compliant constant force mechanism 300 has one positive stiffness structure 310 and two bistable structures 320, two bistable structures 320 are located on each side of the positive stiffness structure 310 along a first direction (A-A direction), and the positive stiffness structure 310 is connected to the two bistable structures 320.

As shown in fig. 21-27, in some implementations, in one compliant constant force mechanism 300, the number of positive stiffness structures 310 and bistable structures 320 is one, with the positive stiffness structures 310 and bistable structures 320 being disposed sequentially along a first direction (A-A direction).

In some implementations, in one compliant constant force mechanism 300, the number of positive stiffness structures 310 and bistable structures 320 is multiple, and the multiple positive stiffness structures 310 and the multiple bistable structures 320 are alternately arranged along the first direction (A-A direction). The alternate arrangement is that the first positive stiffness structure 310 is arranged along the first direction (A-A direction), the bistable structure 320 is arranged behind the positive stiffness structure 310, and the bistable structure 320 is arranged behind the bistable structure 320, if two adjacent positive stiffness structures 310 exist, the bistable structure 320 is necessarily connected between the two adjacent positive stiffness structures 310; if there are two adjacent bistable structures 320, then a positive stiffness structure 310 must be connected between the two adjacent bistable structures 320.

As shown in fig. 29 and 30, in some implementations, the positive stiffness structure 310 and the bi-stable structure 320 are connected and enclosed to form a cylindrical structure. The axial direction of the tubular structure is parallel to the first direction (A-A direction), i.e. the tubular structure is stretchable in the first direction (A-A direction). The positive stiffness structure 310 and the bi-stable structure 320 are connected and enclosed to form a cylindrical structure.

As shown in fig. 16 and 17, in some implementations, the bistable structure 320 includes a first flexible beam 321, a second flexible beam 322, and a first rigid block 323, a second rigid block 324, and a third rigid block 325 extending along a first direction (A-A direction), the second rigid block 324 and the third rigid block 325 being located on both sides of the first rigid block 323 in a second direction (B-B direction), respectively, the first direction (A-A direction) being perpendicular to the second direction (B-B direction), at least one first flexible beam 321 being disposed between the second rigid block 324 and the first rigid block 323, at least one second flexible beam 322 being disposed between the third rigid block 325 and the first rigid block 323, the first flexible beam 321 and the second flexible beam 322 each being disposed obliquely to the first direction (A-A direction), the first flexible beam 321 and the second flexible beam 322 being disposed symmetrically with respect to the first rigid block 323. The length direction of the base 110 is parallel to a first direction (A-A direction), the width direction of the base 110 is parallel to a second direction (B-B direction), and the first direction (A-A direction) and the second direction (B-B direction) are perpendicular to the thickness direction (C-C direction) of the base 110, respectively.

In this arrangement, the first, second and third rigid blocks 323, 324, 325 provide support for the ends of the first and second flexible beams 321, 322, and the first and second flexible beams 321, 322 elastically deform when the compliant constant force mechanism 300 is compressed in a first direction (A-A direction). In fig. 17, in one bistable structure 320, two first flexible beams 321 are provided in a first rigid block 323 and a second rigid block 324, two second flexible beams 322 are provided between a third rigid block 325 and the first rigid block 323, and the two first flexible beams 321 and the two second flexible beams 322 are symmetrically provided with respect to the longitudinal direction of the first rigid block 323.

In some implementations, as shown in fig. 15 and 16, the number of bistable structures 320 is two, two first rigid blocks 323 are arranged at intervals along the first direction (A-A direction), two second rigid blocks 324 are integrated, two third rigid blocks 325 are integrated, and two ends of the positive rigid structure 310 are respectively connected with the two first rigid blocks 323. So configured, the two bistable structures 320 share the same second rigid block 324 and share the same third rigid block 325, which facilitates the manufacturing of compliant constant force structures and facilitates the enhancement of structural stability.

In some implementations, the positive stiffness structure 310 includes bending pieces, the bending pieces include third flexible beams 311 and connecting beams 312, the number of the third flexible beams 311 is plural, the plurality of third flexible beams 311 are arranged at intervals along the first direction (A-A direction), each third flexible beam 311 is respectively arranged parallel to the second direction (B-B direction), the plurality of third flexible beams 311 are sequentially connected in an anti-series manner through the connecting beams 312, and the third flexible beams 311 at the edge are connected with the first rigid block 323. For example, in fig. 16, the positive stiffness structure 310 includes two bending members symmetrically disposed with respect to the central axis of the first rigid block 323 in the length direction, wherein the connecting beam 312 in one bending member is close to the second rigid block 324, the connecting beam 312 in the other bending member is close to the third rigid block 325, taking the bending member close to the second rigid block 324 as an example, the bending member includes four third flexible beams 311 disposed at intervals along the first direction (A-A direction), one end of the third flexible beam 311 close to the second rigid block 324 is called a first end, the other end is called a second end, and then the second end of the first third flexible beam 311 from left to right in the direction shown in fig. 16 is connected to the first rigid block 323, the first end of the first third flexible beam 311 is connected to the first end of the second third flexible beam 311 through the first connecting beam 312, the second end of the second third flexible beam 311 is connected to the second end of the third flexible beam 311 through the second connecting beam 312, and the third end of the third flexible beam 311 is connected to the third end of the fourth flexible beam 311. In fig. 12, the number of bistable structures 320 is two, the number of first rigid blocks 323 is two, and the second end of the third flexible beam 311 is connected to another first rigid block 323.

As shown in fig. 15 and 16, in some implementations, the connection beams 312 are flexible straight beams, with the connection beams 312 disposed parallel to the first direction (A-A direction). The flexible straight beam may be a rectangular plate-like structure extending in the first direction (A-A direction) or a tubular structure extending in the first direction (A-A direction). The stiffness of the flexible straight beam is much less than any one of the first, second and third rigid blocks 323, 324 and 325. The rigidity of the flexible straight beam can be adjusted by changing the size, the structural shape, the material and the like of the flexible straight beam.

In some implementations, as shown in fig. 17, the connecting beam 312 is an arc beam. In this arrangement, a plurality of third flexible beams 311 spaced apart along the first direction (A-A direction) are connected to the arcuate beams to form a coiled flexure. The arc beam may reduce the formation of stress concentration areas at the junction of the connecting beam 312 and the third flexible beam 311.

As shown in fig. 18, in some implementations, the positive stiffness structure 310 includes a third flexible beam 311, the third flexible beam 311 being disposed parallel to the second direction (B-B direction), the third flexible beam 311 being disposed between the first rigid block 323 and the second rigid block 324, and between the first rigid block 323 and the third rigid block 325. In this arrangement, the positive stiffness structure 310 does not include the connecting beam 312, and the third flexible beam 311 is connected at one end to the first rigid block 323 and at the other end to the second or third rigid block 324, 325.

As shown in fig. 19, in some implementations, the positive stiffness structure includes a third flexible beam 311, the third flexible beam 311 including a first segment 3111, a second segment 3112, and a third segment 3113, the first segment 3111 and the second segment 3112 being parallel to the second direction (B-B direction), the third segment 3113 being parallel to the first direction (A-A direction), the first segment 3111 being connected to the first rigid block 323, the first segment 3111 and the third segment 3113 being connected by a second segment 3112, the third segment 3113 being connected to the second rigid block 324 or the third rigid block 325, between the first rigid block 323 and the second rigid block 323.

As shown in fig. 20, in some implementations, the positive stiffness structure 310 includes a third flexible beam 311 and a connecting beam 312, the third flexible beams 311 are connected to two first rigid blocks 323, the third flexible beams 311 connected to the two first rigid blocks 323 are symmetrically arranged, and the two symmetrical third flexible beams 311 are connected through the connecting beam 312, and each third flexible beam 311 is arranged obliquely to the first direction (A-A direction). The inclination directions of the two third flexible beams 311 connected by the connection beam 312 are opposite, the inclination directions of the third flexible beam 311 and the adjacent first flexible beam 321 or second flexible beam 322 are the same, and the inclination angles of the third flexible beam 311 and the adjacent first flexible beam 321 may be the same or different. With continued reference to fig. 20, with the side surface of the first rigid block 323 facing the other first rigid block 323 as the inner side surface, when a plurality of third flexible beams 311 are disposed on the first rigid block 323 at intervals, the distance between the third flexible beams 311 and the first rigid block 323 at the inner side surface is L, and two third flexible beams 311 with the same L value in the two first rigid blocks 323 are connected by the connecting beam 312. Illustratively, in fig. 20, two third flexible beams 311 are respectively disposed on the left first rigid block 323 and the right first rigid block 323, and the rightmost third flexible beam 311 in the left first rigid block 323 is connected to the leftmost third flexible beam 311 in the right first rigid block 323 through a connecting beam 312, and the left third flexible beam 311 in the left rigid block is connected to the right third flexible beam 311 in the right rigid block through the connecting beam 312.

In some implementations, the folding mechanism further includes a transmission assembly including a first transmission structure 410 and a second transmission structure 420, the first transmission structure 410 is disposed on the first swing arm 211 and/or the second swing arm 212, the second transmission structure 420 is disposed on the compliant constant force mechanism 300, the first transmission structure 410 is in transmission connection with the second transmission structure 420, and the first transmission structure 410 moves to drive the second transmission structure 420 to move along the first direction (A-A direction). The first transmission structure 410 moves with the rotation of the first swing arm 211 and/or the second swing arm 212, the first transmission structure 410 moves the second transmission structure 420 along the first direction (A-A direction) during the movement, and the second transmission structure 420 compresses the compliant constant force mechanism 300.

The first swing arm 211 or the second swing arm 212 for compressing the compliant constant force mechanism 300 is provided with a first transmission structure 410. The first transmission structure 410 is arranged on the first swing arm 211 in the same manner as the second swing arm 212, and the first transmission structure 410 and the first swing arm 211 may be fixedly connected, detachably connected, or the first transmission structure 410 and the first swing arm 211 are integrally formed and manufactured as an integral structure.

As shown in fig. 8 and 14, in some implementations, the first transmission structure 410 includes a first cam structure 411 and the second transmission structure 420 includes a second cam structure 421, the first cam structure 411 and the second cam structure 421 being in contact, the first cam structure 411 rotating to move the second cam structure 421 in a first direction (A-A direction). In this arrangement, the transmission assembly is used to convert rotary motion into linear motion. The first cam structure 411 has a first working surface, the second cam structure 421 has a second working surface, the first working surface has a first peak surface and a first trough surface which are mutually connected in the circumferential direction with the rotation axis of the first cam structure 411 as an axis, and the second working surface has a second peak surface and a second trough surface which are mutually connected in the circumferential direction with the rotation axis of the second cam structure 421 as an axis. When the first wave trough surface is opposite to the second wave trough surface, and at this time, the compression amount of the compliant constant force mechanism 300 is relatively small. During folding or unfolding of the folding mechanism, the first swing arm 211 and the second swing arm 212 both rotate, and the first cam structure 411 rotates along with the first swing arm 211 or the second swing arm 212 connected with the first cam structure 411, so that the position of the first crest surface and the position of the first trough surface change, and the first crest surface moves to the second crest surface along the second trough surface, and during moving, because the position of the first cam structure 411 in the first direction (A-A direction) is unchanged, the first cam structure 411 pushes the second cam structure 421 to move away from the first cam structure 411 through the first crest surface, that is, the second cam structure 421 moves away from the first cam structure 411 along the first direction (A-A direction), so as to compress the flexible constant force mechanism 300. The amount of compression of the compliant constant force mechanism 300 is relatively greater when the first peak surface is in contact with the second peak surface.

As shown in fig. 6, in some implementations, the folding mechanism further includes a positioning shaft 220, the first cam structure 411 is provided with a first through hole along a first direction (A-A direction), the second cam structure 421 is provided with a second through hole along the first direction (A-A direction), and the positioning shaft 220 sequentially penetrates the first through hole and the second through hole. The positioning shaft 220 plays a limiting role on both the first cam structure 411 and the second cam structure 421, and the positioning shaft 220 does not limit the movement of the first cam structure 411 and the second cam structure 421 in the first direction (A-A direction), but rather limits the movement of the first cam structure 411 and the second cam structure 421 in the radial direction, so that the stability is higher when the second cam structure 421 moves in the first direction (A-A direction), and the first cam structure 411 and the second cam structure 421 are always in the coaxial arrangement state.

In some embodiments, as shown in fig. 5 and 6, the folding mechanism further includes a synchronization structure 600, where the synchronization structure 600 may include a first gear and a second gear, the first gear is meshed with the second gear, the first gear is sleeved on a first gear shaft, the second gear is sleeved on a second gear shaft, and the positioning shaft 220 may be connected to the first gear shaft and/or the second gear shaft.

As shown in fig. 14, in some implementations, the first swing arm 211 is provided with two first transmission structures 410 at intervals along the first direction (A-A direction), the second swing arm 212 is provided with two first transmission structures 410 at intervals along the first direction (A-A direction), the compliant constant force mechanism 300 is provided with four second transmission structures 420, and the four second transmission structures 420 are in one-to-one transmission connection with the four first transmission structures 410. In this arrangement, during the folding mechanism opening and closing process, the two first transmission structures 410 on the first swing arm 211 drive the second transmission structures 420 to compress the compliant constant force mechanism 300 from two sides of the compliant constant force mechanism 300 along the first direction (A-A direction), the two first transmission structures 410 on the second swing arm 212 drive the second transmission structures 420 to compress the compliant constant force mechanism 300 from two sides of the compliant constant force mechanism 300 along the first direction (A-A direction), and the compliant constant force mechanism 300 applies a reaction force to both the first swing arm 211 and the second swing arm 212.

In the above-described folding mechanism, both sides of the compliant constant force mechanism 300 in the first direction (A-A direction) are positioned by the cooperation between the second transmission structure 420 and the first transmission structure 410, and the arrangement of the positioning shaft 220.

As shown in fig. 21-24, in some implementations, the folding mechanism further includes a connection mechanism 500, the connection mechanism 500 being rotatably connected with the base 110; the first swing arm 211 is slidably connected with the connecting mechanism 500 along the second direction (B-B direction), and the flexible constant force mechanism 300 is installed on the connecting mechanism 500; and/or the second swing arm 212 is slidably coupled to the connection mechanism 500 in a second direction (B-B direction), and the compliant constant force mechanism 300 is mounted to the connection mechanism 500.

In this arrangement, during the opening and closing of the folding mechanism, the first swing arm 211 and/or the second swing arm 212 move in the second direction (B-B direction) relative to the corresponding connection mechanism 500, compressing the compliant constant force mechanism 300 during the movement of the first swing arm 211 and/or the second swing arm 212.

In some embodiments, as shown in fig. 5, the folding mechanism further includes a first door panel 710, a first door panel swing arm 711, a second door panel 720, and a second door panel swing arm 721, where the first door panel 710 and the second door panel 720 are respectively located at two sides of the base 110 along the second direction (B-B direction), the first door panel swing arm 711 and the second door panel swing arm 721 are respectively rotatably connected with the base 110, the first door panel 710 is connected with the first door panel swing arm 711, and the second door panel 720 is connected with the second door panel swing arm 721. The connection mechanism 500 connected to the first swing arm 211 may be connected to the first door panel 710 or the first door panel swing arm 711, and the connection mechanism 500 connected to the second swing arm 212 may be connected to the second door panel 720 or the second door panel swing arm 721.

In some embodiments, the first door panel 710 is connected to a first housing 741 of the folding electronic device, the second door panel 720 is connected to a second housing 742, the folding electronic device to which the folding mechanism is applied may include a middle frame, and the first housing 741 and the second housing 742 may be part of the middle frame, respectively. The connection mechanism 500 connected to the first swing arm 211 may be connected to the first housing 741, and the connection mechanism 500 connected to the second swing arm 212 may be connected to the second housing 742.

In a specific embodiment, at least one connection mechanism 500 is disposed on two sides of the base 110 along the second direction (B-B direction), that is, at least one connection mechanism 500 is disposed corresponding to the first swing arm 211, and at least one other connection mechanism 500 is disposed corresponding to the second swing arm 212.

In some implementations, one of the first and second drive structures 410, 420 includes a slider 422, the other includes a chute 412, the chute 412 is an arcuate slot, and the slider 422 is slidably coupled to the chute 412. In this arrangement, when the folding mechanism is opened and closed, the slider 422 moves along the curved sliding slot 412, so that the distance between the structure connected with the slider 422 and the structure connected with the sliding slot 412 changes with the change of the relative position of the slider 422 in the sliding slot 412, that is, the compression amount of the compliant constant force mechanism 300 changes. As shown in fig. 23, the first transmission structure 410 includes a sliding slot 412, the second transmission structure 420 includes a sliding block 422, the first swing arm 211 and the second swing arm 212 are both provided with the sliding slot 412, taking the assembly between the first swing arm 211 and the compliant constant force mechanism 300 as an example, one side of the first swing arm 211 facing the compliant constant force mechanism 300 is provided with the sliding slot 412, the sliding slot 412 extends to be an arc surface along the second direction (B-B direction), the compliant constant force mechanism 300 is provided with the sliding block 422, the sliding block 422 contacts with the arc surface of the sliding slot 412, during the opening and closing process of the folding mechanism, the first swing arm 211 moves in the second direction (B-B direction) relative to the connection mechanism 500, so that the contact position between the sliding slot 412 and the sliding block 422 changes, and during the movement of the sliding block 422 from the deepest position near the slot 412 to the edge direction, the sliding block 422 moves away from the first swing arm 211, and the sliding block 422 compresses the compliant constant force mechanism 300.

In some embodiments, the two sides of the first swing arm 211 may be respectively provided with a compliant constant force mechanism 300 along the first direction (A-A direction), the two sides of the first swing arm 211 along the first direction (A-A direction) are respectively provided with a sliding slot 412, one sliding block 422 connected with the compliant constant force mechanism 300 is contacted with the sliding slot 412 on one side of the first swing arm 211, and the other sliding block 422 connected with the other compliant constant force mechanism 300 is contacted with the sliding slot 412 on the other side of the first swing arm 211.

One or more sliding grooves 412 may be provided on the same side of the first swing arm 211, and illustratively, in fig. 23, two sliding grooves 412 are provided on the first swing arm 211 in the second direction (B-B direction) corresponding to one slider 422.

In some implementations, as shown in fig. 23, the connection mechanism 500 is provided with a guide slot 510, and the slider 422 passes through the guide slot 510 and contacts the slide slot 412. The guide groove 510 plays a limiting role on the slider 422, and the guide groove 510 extends along the first direction (A-A direction) so that the stability is stronger in the moving process of the slider 422 along the first direction (A-A direction).

As shown in FIG. 24, the slider 422 and the compliant constant force mechanism 300 may be fixedly connected, detachably connected, or may be of an integral structure. The slider 422 may be connected to the first rigid block 323, or the slider 422 may be integrally formed with the first rigid block 323. The end of the slider 422, which is used to contact the wall surface of the chute 412, has an arc surface (4231), so that friction between the slider 422 and the wall surface of the chute 412 can be reduced.

As shown in fig. 25-29, in some implementations, one of the first and second drive structures 410, 420 includes a bevel 413, the bevel 413 being disposed obliquely relative to a second direction (B-B direction) that is perpendicular to the first direction (A-A direction). Since the first transmission structure 410 moves in the second direction (B-B direction) relative to the second transmission structure 420 under the driving of the first swing arm 211 and/or the second swing arm 212 connected thereto during the opening and closing of the folding mechanism, when one of the first transmission structure 410 and the second transmission structure 420 has the inclined surface 413 inclined relative to the second direction (B-B direction), the one of the first transmission structure 410 and the second transmission structure 420 can be made to move in the first direction (A-A direction), and the position of the first transmission structure 410 in the first direction (A-A direction) is unchanged due to the connection of the first transmission structure 410 with the first swing arm 211 and/or the second swing arm 212, so that the position of the second structure in the first direction (A-A direction) is changed, thereby compressing the compliant constant force mechanism 300.

As shown in fig. 26, 27 and 28, taking the example that the first transmission structure 410 is connected to the second swing arm 212 as an example, in one arrangement, the first transmission structure 410 includes a slope 413, one end of the second transmission structure 420 is in contact with the slope 413, and during the movement of the first transmission structure 410 relative to the connection mechanism 500 in the second direction (B-B direction), since the position of the second transmission structure 420 and the connection mechanism 500 in the second direction (B-B direction) is unchanged, the contact area between the second transmission structure 420 and the slope 413 changes, the compression amount of the compliant constant force mechanism 300 is relatively large when the second transmission structure 420 is in contact with the area of the slope 413 closer to the compliant constant force mechanism 300, and the compression amount of the compliant constant force mechanism 300 is relatively small when the second transmission structure 420 is in contact with the area of the slope 413 further away from the compliant constant force mechanism 300.

In some implementations, one of the first and second drive structures 410, 420 where the bevel 413 is not disposed includes a bump 423, the bump 423 having an arcuate surface (4231), the arcuate surface (4231) being in contact with the bevel 413. That is, when the first transmission structure 410 includes the inclined surface 413, the second transmission structure 420 includes the protrusion 423; when the second transmission structure 420 includes the inclined surface 413, the first transmission structure 410 includes the protrusion 423. Since the bump 423 has the circular arc surface (4231), the circular arc surface (4231) is in contact with the inclined surface 413, and thus the friction force between the bump 423 and the inclined surface 413 is relatively small.

The folding mechanism provided in this embodiment is based on the theory of compliant mechanics, and is capable of providing a constant damping force, and the compliant constant force mechanism 300 included in the folding mechanism replaces the spring structure, so that the number of parts required to be assembled by the folding mechanism is reduced, and the assembly process is simplified. Meanwhile, the folding mechanism outputs a constant force in a working interval, the output force of the folding mechanism is not influenced by the abrasion loss of a transmission component (such as the first cam structure 411 or the second cam structure 421), so that the opening and closing retaining force of the folding mechanism is more stable, and the mechanical property and the working adaptability of the folding mechanism are optimized.

As shown in fig. 5 to 8 and 14, in one embodiment, the folding mechanism includes two swing arm groups, which are respectively disposed at two ends of the base 110 along a first direction (A-A direction), each swing arm group includes a first swing arm 211 and a second swing arm 212, one swing arm group is correspondingly provided with a compliant constant force mechanism 300, taking connection of one swing arm group and the compliant constant force mechanism 300 as an example, the first swing arm 211 is provided with two first transmission structures 410 at intervals along the first direction, the second swing arm 212 is provided with two first transmission structures 410 at intervals along the first direction (A-A direction), the compliant constant force mechanism 300 is provided with four second transmission structures 420, the four first transmission structures 410 are in one-to-one corresponding transmission connection with the four second transmission structures 420, so that in the process of rotating the first swing arm 211 and the second swing arm 212, taking the direction in fig. 14 as an example, the first direction (A-A direction) is the left-right direction, the two first transmission structures 410 on the left side drive the two second transmission structures 420 to move rightwards, the two first transmission structures 410 on the right side drive the two second transmission structures 420 to move leftwards, and the second transmission structures 420 on the left side and the right side of the flexible constant force mechanism 300 respectively squeeze the flexible constant force mechanism 300 from two sides, thereby realizing the compression of the flexible constant force mechanism 300.

As shown in fig. 21 to 23, in another embodiment, the folding mechanism includes two swing arm groups, the two swing arm groups are respectively disposed at two ends of the base 110 along a first direction (A-A direction), each swing arm group includes a first swing arm 211 and a second swing arm 212, each swing arm group is correspondingly provided with four compliant constant force mechanisms 300, that is, each first swing arm 211 is correspondingly provided with two compliant constant force mechanisms 300, each second swing arm 212 is correspondingly provided with two compliant constant force mechanisms 300, taking the connection of the first swing arm 211 and the compliant constant force mechanism 300 in one of the swing arm groups as an example, taking the direction in fig. 21 as an example, the first direction (A-A direction), the left side of the first swing arm 211 is provided with two arc-shaped slide grooves 412 at intervals along the second direction, the left side and the right side of the first swing arm 211 are respectively provided with one compliant constant force mechanism 300, the compliant slide grooves 412 connected with the compliant constant force mechanisms 422 on the left side are located at the two symmetrical slide grooves 412 on the two sides of the first swing arm 211, and the compliant slide grooves 412 on the two sides of the first swing arm 211 are located at the two symmetrical slide grooves 412 on the two sides of the left side and the right side of the first swing arm 412.

In yet another embodiment, as shown in fig. 25, 26 and 29, two compliant constant force mechanisms 300 are provided for one swing arm group of the folding mechanism, one compliant constant force mechanism 300 is provided for the first swing arm 211, and one compliant constant force mechanism is provided for the second swing arm 212.

The above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A folding mechanism, comprising:

a base (110), the base (110) extending in a first direction;

The folding assembly comprises at least one swing arm group, each swing arm group comprises a first swing arm (211) and a second swing arm (212) which are respectively positioned at two sides of the base (110), and the first swing arm (211) and the second swing arm (212) are respectively connected with the base (110) in a rotating way;

-a compliant constant force mechanism (300), said first swing arm (211) and/or said second swing arm (212) compressing said compliant constant force mechanism (300) when rotated, said compliant constant force mechanism (300) outputting a constant force to said first swing arm (211) and/or said second swing arm (212) when the rotation angle of said first swing arm (211) and/or said second swing arm (212) is within a first angular range;

The compression amount of the working interval of the flexible constant force mechanism (300) is between S2 and S3, wherein S2 is larger than the starting point S1 of the compression amount corresponding to the constant force interval output by the flexible constant force mechanism (300), and S3 is smaller than or equal to the ending point S4 of the compression amount corresponding to the constant force interval output by the flexible constant force mechanism (300);

The compliant constant force mechanism (300) comprises a positive stiffness structure (310) and a bistable structure (320), wherein the positive stiffness structure (310) is connected with the bistable structure (320), the reaction force generated by the positive stiffness structure (310) increases along with the increase of the compression amount of the compliant constant force mechanism (300), and the reaction force generated by the bistable structure (320) generates periodic variation along with the increase of the compression amount of the compliant constant force mechanism (300); at least when the rotation angle of the first swing arm (211) and/or the second swing arm (212) is within a first angle range, the resultant force of the positive stiffness structure (310) and the bistable structure (320) is a fixed value.

2. The folding mechanism of claim 1, wherein the number of positive stiffness structures (310) and the number of bi-stable structures (320) are one, the positive stiffness structures (310) and the bi-stable structures (320) being disposed sequentially along the first direction.

3. The folding mechanism of claim 1, wherein the number of positive stiffness structures (310) is one, the number of bistable structures (320) is two, two bistable structures (320) are located on either side of the positive stiffness structures (310) in the first direction, and the positive stiffness structures (310) are connected to the two bistable structures (320), respectively.

4. The folding mechanism of claim 1, wherein the number of positive stiffness structures (310) and the number of bi-stable structures (320) are each a plurality, the plurality of positive stiffness structures (310) and the plurality of bi-stable structures (320) being alternately arranged along the first direction.

5. The folding mechanism of claim 1, wherein the positive stiffness structure (310) and the bi-stable structure (320) are connected and enclosed to form a tubular structure.

6. The folding mechanism of claim 1, wherein the bistable structure (320) comprises a first flexible beam (321), a second flexible beam (322), and a first rigid block (323), a second rigid block (324) and a third rigid block (325) extending in a first direction, in a second direction, the second rigid block (324) and the third rigid block (325) being located on both sides of the first rigid block (323), respectively, the first direction being perpendicular to the second direction, at least one first flexible beam (321) being provided between the second rigid block (324) and the first rigid block (323), at least one second flexible beam (322) being provided between the third rigid block (325) and the first rigid block (323), the first flexible beam (321) and the second flexible beam (322) being arranged obliquely to the first direction, the first flexible beam (321) and the second flexible beam (322) being arranged symmetrically with respect to the first rigid block (323).

7. The folding mechanism according to claim 6, wherein the number of bistable structures (320) is two, two first rigid blocks (323) are arranged at intervals along the first direction, two second rigid blocks (324) are integrated, two third rigid blocks (325) are integrated, and two ends of the positive rigid structure (310) are respectively connected with the two first rigid blocks (323).

8. The folding mechanism as claimed in claim 6, wherein the positive stiffness structure (310) includes a bending member, the bending member includes a third flexible beam (311) and a connecting beam (312), the number of the third flexible beams (311) is plural, the plurality of the third flexible beams (311) are arranged at intervals along the first direction, each of the third flexible beams (311) is arranged parallel to the second direction, the plurality of the third flexible beams (311) are sequentially connected in an inverse series manner through the connecting beam (312), and the third flexible beam (311) at an edge portion is connected with the first rigid block (323).

9. The folding mechanism of claim 8, wherein the connecting beam (312) is a flexible straight beam, the connecting beam (312) being disposed parallel to the first direction.

10. The folding mechanism of claim 8, wherein the connecting beam (312) is an arcuate beam.

11. The folding mechanism of claim 6, wherein the positive stiffness structure (310) comprises a third flexible beam (311), the third flexible beam (311) being disposed parallel to the second direction, the third flexible beam (311) being disposed between the first rigid block (323) and the second rigid block (324), and between the first rigid block (323) and the third rigid block (325).

12. The folding mechanism of claim 6, wherein the positive stiffness structure comprises a third flexible beam (311), the third flexible beam (311) being disposed between the first rigid block (323) and the second rigid block (324), between the first rigid block (323) and the third rigid block (325), the third flexible beam (311) comprising a first section (3111), a second section (3112) and a third section (3113), the first section (3111) and the second section (3112) being parallel to the second direction, the third section (3113) being parallel to the first direction, the first section (3111) being connected to the first rigid block (323), the first section (3111) and the third section (3113) being connected by the second section (3112), the third section (3113) being connected to the second rigid block (324) or the third rigid block (325).

13. The folding mechanism according to claim 7, wherein the positive stiffness structure (310) includes a third flexible beam (311) and a connecting beam (312), the third flexible beams (311) are connected to two first rigid blocks (323), the third flexible beams (311) connected to two first rigid blocks (323) are symmetrically arranged, and the symmetrical two third flexible beams (311) are connected by the connecting beam (312), and each third flexible beam (311) is arranged obliquely to the first direction.

14. The folding mechanism of any of claims 1-13, further comprising a drive assembly, the drive assembly comprising a first drive structure (410) and a second drive structure (420), the first drive structure (410) being disposed on the first swing arm (211) and/or the second swing arm (212), the second drive structure (420) being disposed on the compliant constant force mechanism (300), the first drive structure (410) being in drive connection with the second drive structure (420), the first drive structure (410) moving to drive the second drive structure (420) to move in the first direction.

15. The folding mechanism of claim 14, wherein the first transmission structure (410) includes a first cam structure (411), the second transmission structure (420) includes a second cam structure (421), the first cam structure (411) and the second cam structure (421) are in contact, and rotation of the first cam structure (411) moves the second cam structure (421) in the first direction.

16. The folding mechanism of claim 15, further comprising a positioning shaft (220), wherein the first cam structure (411) is provided with a first through hole along the first direction, and the second cam structure (421) is provided with a second through hole along the first direction, and the positioning shaft (220) sequentially penetrates through the first through hole and the second through hole.

17. The folding mechanism according to claim 15, wherein the first swing arm (211) is provided with two first transmission structures (410) at intervals along the first direction, the second swing arm (212) is provided with two first transmission structures (410) at intervals along the first direction, the compliant constant force mechanism (300) is provided with four second transmission structures (420), and the four second transmission structures (420) are in one-to-one transmission connection with the four first transmission structures (410).

18. The folding mechanism of claim 14, further comprising a connection mechanism (500), the connection mechanism (500) being rotatably connected with the base (110);

The first swing arm (211) is in sliding connection with the connecting mechanism (500) along the second direction, and the flexible constant force mechanism (300) is arranged on the connecting mechanism (500); and/or the second swing arm (212) is slidably connected with the connecting mechanism (500) along the second direction, and the flexible constant force mechanism (300) is installed on the connecting mechanism (500);

the second direction is perpendicular to the first direction.

19. The folding mechanism of claim 14, wherein one of the first transmission structure (410) and the second transmission structure (420) includes a slider (422), the other includes a chute (412), the chute (412) is an arcuate slot, and the slider (422) is slidably coupled to the chute (412).

20. The folding mechanism of claim 19, further comprising a connection mechanism (500), the connection mechanism (500) being rotatably connected with the base (110); the connecting mechanism (500) is provided with a guide groove (510), and the sliding block (422) passes through the guide groove (510) and then contacts with the sliding groove (412).

21. The folding mechanism of claim 14, wherein one of the first transmission structure (410) and the second transmission structure (420) includes a ramp (413), the ramp (413) being disposed obliquely relative to the second direction, the second direction being perpendicular to the first direction.

22. The folding mechanism of claim 21, characterized in that the other of the first transmission structure (410) and the second transmission structure (420) comprises a projection (423), the projection (423) having an arc surface (4231), the arc surface (4231) being in contact with the bevel (413).

23. A foldable electronic device, comprising a first housing (741), a second housing (742), a display (730) and a folding mechanism (100) according to any one of claims 1-22, wherein the folding mechanism (100) is connected between the first housing (741) and the second housing (742), the display (730) is mounted on the first housing (741), the second housing (742) and the folding mechanism (100), and when a swing arm set in the folding mechanism (100) rotates, the first housing (741) and the second housing (742) relatively rotate, so as to drive the display (730) to bend or unfold.