CN109268439B

CN109268439B - Hydraulic bushing

Info

Publication number: CN109268439B
Application number: CN201811273762.3A
Authority: CN
Inventors: 丁行武; 邹波; 刘桂杰; 卜继玲; 姜其斌; 约瑟夫·格罗斯; 王涛
Original assignee: Zhuzhou Times New Material Technology Co Ltd
Current assignee: Zhuzhou Times New Material Technology Co Ltd
Priority date: 2018-10-30
Filing date: 2018-10-30
Publication date: 2024-04-09
Anticipated expiration: 2038-10-30
Also published as: CN109268439A

Abstract

The present invention provides a hydraulic bushing comprising: a mandrel; a sleeve-shaped first runner body sleeved on the mandrel, wherein a gap between the mandrel and the first runner body is filled with a first rubber body, and a first runner for hydraulic fluid is constructed on the outer surface of the first runner body; and the outer sleeve is tightly sleeved on the radial outer side of the first runner body. Two main fluid chambers for receiving hydraulic fluid are formed radially opposite one another on the first rubber body, which communicate with one another via a first flow channel. At least one axially outer side of the first flow channel body is provided with a sealing assembly which together with the jacket defines an auxiliary liquid chamber. A second flow passage body is arranged in the auxiliary liquid cavity, and a second flow passage for hydraulic fluid is constructed on the outer surface of the second flow passage body.

Description

Hydraulic bushing

Technical Field

The present invention relates to a hydraulic bushing for a vehicle, in particular a rail vehicle.

Background

Hydraulic bushings are a component widely used in vehicles (e.g., automobiles and railway vehicles), and are mainly mounted on a suspension or a bogie of the vehicle for buffering vibration and impact to improve the stability and safety of the running of the vehicle.

Chinese patent document CN108150536a discloses a hydraulic bushing. The hydraulic bushing comprises a mandrel, a first fluid sleeved outside the mandrel, and an outer sleeve tightly sleeved outside the first fluid. A gap between the mandrel and the first fluid is filled with a first rubber body, and a groove is formed on the outer surface of the first fluid. Two liquid cavities for containing liquid are formed on the first rubber body in a radial opposite mode, wherein the grooves and the outer sleeve enclose a flow channel, and the two liquid cavities are communicated through the flow channel. By means of the flowability between the hydraulic fluid in the two fluid chambers, the stiffness of the hydraulic bushing can be adjusted, so that an improved stability of the vehicle in driving, in particular when the vehicle is cornering, is achieved.

However, in the above hydraulic bushings, the range of stiffness and damping adjustment is still limited. Accordingly, it is desirable in the art to provide a hydraulic bushing having a stiffness and damping that can be varied over a greater range to provide greater stability and safety for the vehicle to travel.

Disclosure of Invention

The present invention aims to provide a novel hydraulic bushing which can realize a rigidity-changing function in both radial and axial directions.

According to the present invention, there is provided a hydraulic bushing comprising: a mandrel; a sleeve-shaped first runner body sleeved on the mandrel, a first rubber body is filled in a gap between the mandrel and the first runner body, and a first runner for hydraulic fluid is constructed on the outer surface of the first runner body; and the outer sleeve is tightly sleeved on the radial outer side of the first runner body. Wherein two main fluid chambers for receiving hydraulic fluid are formed radially opposite one another on the first rubber body, which communicate with one another via the first flow channel. A seal assembly is disposed axially outwardly of at least one of the first flow passage bodies, the seal assembly and the jacket cooperatively defining an auxiliary fluid chamber in which a second flow passage body is disposed and on an outer surface of which a second flow passage for hydraulic fluid is constructed.

In a preferred embodiment, the seal assembly comprises a support ring sleeved on the mandrel, the support ring comprising a radial projection in the auxiliary liquid chamber, the radial projection being in sealing contact with the radially inner surface of the second flow passage body, thereby separating the auxiliary liquid chamber into a first subchamber and a second subchamber axially adjacent to each other.

In a preferred embodiment, the second flow passage communicates the first subchamber and the second subchamber with each other.

In a preferred embodiment, one end of the second flow passage is connected to one of the first and second subchambers and the other end is connected to the other of the first and second subchambers.

In a preferred embodiment, the seal assembly further comprises a second rubber body vulcanized on the support ring, the second rubber body comprising a first portion in sealing contact with an axial end of the first runner body and a second portion in sealing contact with an axial end of the outer sleeve, wherein the radial protrusion is axially between the first and second portions.

In a preferred embodiment, the second rubber body further includes a third portion vulcanized onto the radial projection and in sealing contact with the radially inner surface of the second runner body.

In a preferred embodiment, rigid gaskets are embedded in both the first and second portions of the second rubber body.

In a preferred embodiment, the auxiliary liquid chamber extends circumferentially through 360 degrees.

In a preferred embodiment, identical sealing assemblies are provided on both axially outer sides of the first flow channel body.

In a preferred embodiment, the cross-sectional area and length of the first flow passage are determined in accordance with the required radial dynamic stiffness of the hydraulic bushing, and the cross-sectional area and length of the second flow passage are determined in accordance with the required axial dynamic stiffness of the hydraulic bushing.

The hydraulic bushing comprises the auxiliary liquid cavity and the second runner body arranged in the auxiliary liquid cavity, and can realize rigidity adjustment in a larger range in the axial direction and the radial direction, so that the variable rigidity characteristic and the damping effect provided by the hydraulic bushing are improved.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings. Wherein:

fig. 1 schematically shows a cross-sectional view of a hydraulic bushing according to an embodiment of the invention.

Fig. 2 is an enlarged view showing an auxiliary fluid chamber in the hydraulic bushing shown in fig. 1.

In the drawings, like parts are denoted by like reference numerals. The figures are not drawn to scale.

Detailed Description

The invention will be further described with reference to the accompanying drawings. It should be noted that, herein, the terms "axial" and "radial" refer to the horizontal and vertical directions in fig. 1, respectively.

Fig. 1 schematically illustrates a hydraulic bushing 100 according to one embodiment of the invention. As shown in fig. 1, the hydraulic bushing 100 includes a mandrel 10, a first runner body 20 disposed radially outward of the mandrel 10, and an outer jacket 30 that is fitted radially outward of the first runner body 20 in a compressed manner. The first runner body 20 is generally configured in the form of a sleeve member. The mandrel 10 is typically a preform and in the embodiment shown in fig. 1 is configured in the form of a stepped shaft. The two ends of the spindle 10 can be connected, for example, to the bogie of a rail train, while the jacket 30 is connected to the positioning arm. An optional inner sleeve 15 may also be provided over the mandrel 10, as shown in fig. 1. The two axial ends of the outer sleeve 30 are bent radially towards the mandrel 10, forming a flange 32 to facilitate sealing of the hydraulic bushing 100, as will be described in more detail below.

A gap between the mandrel 10 and the first fluid 20 is filled with a first rubber body 40. However, it is understood that where the inner sleeve 15 is provided, the first rubber body 40 may be filled between the inner sleeve 15 and the first fluid 20. On the first rubber body 40, two main liquid chambers 45 for receiving hydraulic fluid are provided, which are preferably configured to be diametrically opposed. That is, both of the main liquid chambers 45 extend only partially in the circumferential direction and are opposed in the radial direction. Grooves, which may be in the form of a spiral circumferential distribution, are formed on the outer surface of the first flow channel body 20. In the assembled state, the jacket 30 is pressed against the first flow channel body 20, so that the grooves on the first flow channel body 20 form a first flow channel 42 for the hydraulic fluid flowing therein. Both ends of the first flow passage 42 are respectively communicated with two main liquid chambers 45. In addition, a liquid injection hole (not shown) for injecting hydraulic fluid is formed in the outer jacket 30 in communication with the first flow passage 42.

When the rail train runs in a straight-line section snakelike-resistant running stage, the wheel pair can bear high-frequency vibration, and when the rail train runs in a low-speed curve, the rim of the wheel pair can be abutted against the steel rail, and the vibration frequency is obviously reduced. Under the two conditions, the movement of the wheels drives the mandrel 10 and the outer sleeve 30 to move relatively, so that the main liquid cavity at the front and the main liquid cavity at the rear expand and contract respectively. In this way, hydraulic fluid can flow between the two main fluid chambers 45 through the first flow passage 42, thereby adjusting the rigidity of the hydraulic bushing 100 accordingly, so that the train keeps running stably. This varying stiffness is an important property of the hydraulic bushing 100.

The above-described features and functions of the hydraulic bushing are known in the art, for example, see the applicant's chinese patent document CN108150536a, which is incorporated herein by reference.

According to the present invention, as shown in fig. 1, both ends of the first flow path body 20 in the axial direction are closed by the seal assembly 50 so as to form a closed chamber for containing hydraulic fluid, i.e., the main liquid chamber 45. The seal assembly 50 includes a rigid support ring 60 that is mounted on the mandrel 10. In the illustrated embodiment, the mandrel 10 is configured as a stepped shaft, and therefore, the support ring 60 is preferably mounted at the stepped structure of the mandrel 10 so as to be well positioned and more stably supported. A second rubber body 70 is vulcanized onto the support ring 60, and rigid gaskets 55, 56 (see fig. 2) are embedded in the second rubber body 70. In this way, the support ring 60 and the gaskets 55, 56 are formed in one piece by the second rubber body 70.

As shown more clearly in fig. 2, the vulcanized second rubber body 70 includes two axially spaced apart portions, an inner portion 72 adjacent the axial end of the first runner body 20 and an outer portion 74 adjacent the axial end of the jacket 30. With this arrangement, the inner portion 72 of the second rubber body 70 forms a seal with the outer surface of the axial end of the first fluid 20, while the outer portion 74 of the second rubber body 70 forms a seal with the inner surface of the flange 32 formed at the axial end of the outer sleeve 30. In this way, a closed auxiliary fluid chamber 80 is formed between the inner portion 72 of the second rubber body 70, the outer portion 74 of the second rubber body 70, the support ring 60 and the outer jacket 30, in which hydraulic fluid can be contained. Unlike the main fluid chamber 45, however, the auxiliary fluid chamber 80 within each seal assembly 50 is configured to extend completely in the circumferential direction, i.e., the auxiliary fluid chamber 80 extends circumferentially through 360 degrees. The auxiliary liquid chamber 80 is not connected to the main liquid chamber 45.

In the preferred embodiment as shown, the support ring 60 also includes a radially outwardly extending tab 62. The tab 62 is axially located between an inner portion 72 and an outer portion 74 of the second rubber body 70. In the assembled state, the radially outwardly projecting projection 62 of the support ring 60 is located within the auxiliary liquid chamber 80. As shown in fig. 2, the outer peripheral end surface of the protruding portion 62 ends in the auxiliary liquid chamber 80, that is, in the radial direction, the protruding portion 62 does not contact the inner surface of the outer jacket 30.

According to the present invention, a second flow passage body 90 is further provided in the auxiliary liquid chamber 80. The second runner 90 is configured as an annular member and is mounted within the outer jacket 30 by an interference fit. Thus, the outer surface of the second runner body 90 is in sealing contact with the inner surface of the outer jacket.

The second flow path body 90 is provided with grooves on the outer peripheral surface thereof, thereby forming a second flow path 92 for hydraulic fluid. As with the first flow passage 42, the second flow passage 92 may also be in a spiral circumferential distribution.

According to the present invention, the inner peripheral surface of the second flow path body 90 is brought into sealing contact with the radially outwardly projecting protrusion 62 of the support ring 60. In the preferred embodiment shown in fig. 2, a third portion 76 of the second rubber body 70 is also provided on the projection 62 of the support ring 60. In this way, the support ring 60 is in contact with the second fluid 90 through the third portion 76 of the second rubber body 70, thereby providing more flexible support for the second fluid 90.

In the present invention, the auxiliary liquid chamber 80 can be further divided into two axially adjacent subchambers, namely, a first subchamber 81 located axially inside and a second subchamber 82 located axially outside, by the sealing contact of the third portion 76 of the second rubber body 70 with the inner peripheral surface of the second flow path body 90. In this case, both ends of the second flow passage 92 of the second flow passage body 90 are connected to the first and second sub-chambers 81 and 82 of the auxiliary liquid chamber 80, respectively, so that the first and second sub-chambers 81 and 82 are communicated with each other. Thus, when the hydraulic bushing 100 is subjected to an axial sinusoidal excitation, the protrusion 62 of the support ring 60 moves axially back and forth, thereby compressing the first and second subchambers 81 and 82 located on the left and right sides thereof. In this way, an internal high pressure is created in one subchamber (e.g., the first subchamber 81) and an internal low pressure is created in the other subchamber (e.g., the second subchamber 82) accordingly, such that hydraulic fluid flows from the subchamber with the internal high pressure (e.g., the first subchamber 81) into the subchamber with the internal low pressure (e.g., the second subchamber 82). The hydraulic bushing 100 produces an axially varying stiffness due to the pressure differential existing between the two subchambers. This further enhances the axial stiffness-changing effect of the hydraulic bushing 100 for the purposes of axial low frequency low stiffness and high frequency high stiffness.

At the same time, the third portion 76 of the second rubber body 70 is brought into flexible contact with the inner peripheral surface of the second flow path body 90, providing a varying displacement in the radial direction. This also provides a somewhat stiffening effect in the radial direction.

Without wishing to be bound by any theory, according to the invention the second flow passage 92 in the auxiliary liquid chamber 80 mainly serves to provide axial stiffness to the hydraulic bushing 100, while the first flow passage 42 in the main liquid chamber 45 mainly serves to provide radial stiffness to the hydraulic bushing 100. Thus, the geometric parameters of the cross-sectional area and length of the first and second flow passages 42, 92 depend on the radial and axial stiffness requirements of the hydraulic bushing 100. The geometric parameters of the first and second flow passages 42, 92 may be selected to be the same as one another or may be selected to be different from one another, depending on the requirements of a particular application.

In addition, in the preferred embodiment shown in fig. 2, the second flow passage body 90, which is constructed as a ring-shaped member, has a flat intermediate region 94 recessed on its inner peripheral surface. The third portion 76 of the second rubber body 70 is in contact with the intermediate region 94 of the second fluid 90. In this way, a more stable support can be provided for the second runner body 90.

In accordance with the present invention, rigid shims 55 and 56 are embedded within the outer and inner portions 74 and 72, respectively, of the rubber body 70, thereby providing a degree of axial rigidity to the hydraulic bushing 100. In addition to providing axial rigidity, the gasket 56 can compress the adjacent second rubber body 70 to fully secure the sealing effect of the hydraulic fluid in the main 45 and auxiliary 80 fluid chambers. The insert 55 can then form a seal against the auxiliary liquid chamber 80 together with the flange 32 of the metal jacket 30 and the outer portion 74 of the second rubber body 70 located therebetween. Thereby, the sealability of the auxiliary liquid chamber 80 is further improved.

It should be noted that seal assemblies are required to be provided at both axial ends of the first fluid. Both seal assemblies may be seal assemblies 50 as described above, or only one of the seal assemblies 50 may be used as described above while the other is a conventional seal. Such a conventional seal need only provide a sealing effect to form a closed main liquid chamber, as will be readily devised by those skilled in the art.

While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. A hydraulic bushing, comprising:

a mandrel;

a sleeve-shaped first runner body sleeved on the mandrel, a first rubber body is filled in a gap between the mandrel and the first runner body, and a first runner for hydraulic fluid is constructed on the outer surface of the first runner body; and

the outer sleeve is tightly sleeved on the radial outer side of the first runner body;

wherein two main fluid chambers for receiving hydraulic fluid are formed radially opposite each other on the first rubber body, which communicate with each other via the first flow channel,

a sealing assembly is arranged on at least one axial outer side of the first runner body, the sealing assembly and the outer sleeve jointly define an auxiliary liquid cavity which extends for 360 degrees in the circumferential direction, a second runner body is arranged in the auxiliary liquid cavity, a second runner for hydraulic fluid is constructed on the outer surface of the second runner body,

the sealing assembly comprises a supporting ring sleeved on the mandrel, the supporting ring comprises a radial protruding part positioned in the auxiliary liquid cavity, the radial protruding part is in sealing contact with the radial inner surface of the second runner body, so as to divide the auxiliary liquid cavity into a first subchamber and a second subchamber which are axially adjacent to each other,

the second flow passage communicates the first subchamber and the second subchamber with each other.

2. The hydraulic bushing of claim 1, wherein said seal assembly further includes a second rubber body vulcanized on said support ring, said second rubber body including a first portion in sealing contact with an axial end of said first runner body and a second portion in sealing contact with an axial end of said jacket, wherein said radial projection is axially between said first and second portions.

3. The hydraulic bushing of claim 2, wherein said second rubber body further includes a third portion vulcanized onto said radial projection and in sealing contact with a radially inner surface of said second runner body.

4. The hydraulic bushing of claim 2, wherein rigid shims are embedded within both the first and second portions of the second rubber body.

5. The hydraulic bushing of any of claims 1-4, wherein the same seal assembly is disposed on both axially outer sides of the first runner body.

6. The hydraulic bushing of any of claims 1-4, wherein a cross-sectional area and a length of the first flow passage are determined based on a desired radial dynamic stiffness of the hydraulic bushing, and a cross-sectional area and a length of the second flow passage are determined based on a desired axial dynamic stiffness of the hydraulic bushing.