CN114504704B

CN114504704B - Injection syringe

Info

Publication number: CN114504704B
Application number: CN202210093638.9A
Authority: CN
Inventors: 侯士双; 陈常娇; 袁霞林
Original assignee: Ningbo Ruiai Product Design Co ltd
Current assignee: Ningbo Ruiai Product Design Co ltd
Priority date: 2022-01-26
Filing date: 2022-01-26
Publication date: 2024-07-30
Anticipated expiration: 2042-01-26
Also published as: CN114504704A

Abstract

The invention relates to an injector, comprising a tube body; the fixing sleeve is vertically arranged in the pipe body and is fixed relative to the pipe body; the injection assembly comprises a needle tube, a piston rod and a needle head, wherein the needle tube is fixedly arranged in the fixed sleeve in a penetrating manner, the piston is arranged in the needle tube and can move up and down relative to the needle tube, the lower end of the piston rod is inserted in the needle tube and can prop against the upper end face of the piston, the piston rod can move up and down along the needle tube, and the needle head is connected with the lower end of the needle tube and extends out of the tube body; the movable sleeve is arranged between the fixed sleeve and the pipe body, the lower end of the movable sleeve can extend out of the pipe body and hide the needle head in the pipe body, and the movable sleeve moves upwards relative to the fixed sleeve when being pressed; the elastic piece acts on the movable sleeve to enable the movable sleeve to always keep a downward moving trend; the handle sleeve is sleeved at the upper end of the pipe body and can move up and down relative to the pipe body, and the handle sleeve is connected with the upper end of the piston rod. The injector is convenient to use and can control the injection speed and the injection quantity.

Description

Injection syringe

Technical Field

The invention relates to the technical field of medical appliances, in particular to an injector.

Background

The injector is widely used in the fields of beauty treatment, medical treatment and the like, and has a manual injection and an automatic injection mode in operation, wherein the manual injector is shown in a 'syringe easy to control injection' disclosed in Chinese patent publication No. CN201720986544.9 (publication No. CN 208598918U), and comprises a needle cylinder, a push rod, a piston and a needle head, and when in injection, 4 fingers of a user are matched with a palm to grasp the needle cylinder, and the push rod is pressed by a thumb to complete injection, so that the following problems exist: 1. the maximum travel of the thumb of an adult is 20mm, and the holding type determines that the syringe cannot be thickened, so that the medicine loading quantity of the syringe is limited; 2. the injector is inconvenient to use, a user firstly holds the needle cylinder by the specified gesture and then presses the push rod by the thumb to complete the injection process, and if the old or other patients with inflexible hands and feet want to complete self injection, a certain using threshold exists.

An automatic injector is disclosed in Chinese patent publication No. CN202020808343.1 (publication No. CN 212395534U), and the injection is automatically completed quickly after the movable sleeve is pressed against the skin, but the injection speed is uncontrollable, the injection quantity is uncontrollable, and even if the injection pen with controllable injection quantity is used, the dosage is firstly set, so that the automatic injector is inconvenient to use and the injection cannot be stopped in the middle.

Disclosure of Invention

The invention aims to solve the technical problem of providing an injector which is convenient to use and can control injection progress and injection quantity aiming at the current state of the art.

The technical scheme adopted for solving the technical problems is as follows: an injector, comprising

The pipe body is vertically arranged and two ends of the pipe body are open;

The fixing sleeve is vertically arranged in the pipe body and is fixed relative to the pipe body;

the injection assembly comprises a needle tube, a piston rod and a needle head, wherein the needle tube is fixedly arranged in the fixed sleeve in a penetrating manner, the piston is arranged in the needle tube and can move up and down relative to the needle tube, the lower end of the piston rod is inserted in the needle tube and can prop against the upper end face of the piston, the piston rod can move up and down along the needle tube, and the needle head is connected with the lower end of the needle tube and extends out of the tube body;

The movable sleeve is arranged between the fixed sleeve and the pipe body, the lower end of the movable sleeve can extend out of the pipe body and hide the needle head in the pipe body, and the movable sleeve moves upwards relative to the fixed sleeve when being pressed;

The elastic piece acts on the movable sleeve to enable the movable sleeve to always keep a downward moving trend;

the novel piston rod is characterized by further comprising a handle sleeve which is sleeved at the upper end of the pipe body and can move up and down relative to the pipe body, and the handle sleeve is connected with the upper end of the piston rod.

In order to prevent the needle from moving downwards to perform injection before penetrating into the skin in place, the tube body is provided with a positioning piece which extends along the axial line direction of the tube body, and the positioning piece can swing along the radial direction of the tube body to a first position which abuts against the handle sleeve to limit the handle sleeve to move downwards or a second position which can be away from the handle sleeve to allow the handle sleeve to move; the movable sleeve is provided with a locking structure capable of positioning the positioning piece at a first position and an unlocking structure allowing the positioning piece to move to a second position, and the locking structure is located above the unlocking structure. Before the movable sleeve moves to the position that the needle penetrates the skin, the locking structure positions the positioning piece at the first position, and the handle sleeve cannot move downwards; after the needle penetrates the skin, the unlocking structure enables the positioning piece to move to the second position, and the handle sleeve can move downwards to perform injection.

The locating piece can have multiple structural style, in order to be convenient for with handle cover, movable sleeve cooperation, simple structure, the locating piece includes extension arm and location portion, the extension arm extends along the axial lead direction of body, and the one end of extension arm links to each other with the body, and the other end links to each other with the location portion, the extension arm can be for the radial swing of body, under the state that the locating piece is in the first position, the front of location portion offsets with the handle cover, the back of location portion offsets with the periphery wall of movable sleeve, the periphery wall of movable sleeve is the locking structure promptly. The outer peripheral wall of the movable sleeve presses the positioning part to be propped against the handle sleeve, and the handle sleeve cannot move downwards to perform injection at the moment; in addition, the invention uses the outer peripheral wall of the movable sleeve as a locking structure, has simple structure and does not need to additionally arrange the locking structure.

In order to be convenient for fix the cover location in the body, the protruding convex part that is equipped with on the periphery wall of fixed cover, link to each other through connecting portion is integrative between body and the fixed cover, set up on the movable sleeve and follow its top downwardly extending in order to dodge the groove of dodging of connecting portion, under the state that the setting element is in the first position, the periphery wall of movable sleeve offsets with the back of setting element, the inner peripheral wall of movable sleeve offsets with the convex part. Because the movable sleeve is provided with the avoidance groove, the peripheral wall of the movable sleeve can have certain elasticity and can swing radially, so that the effect of the peripheral wall of the movable sleeve on the pressing and positioning part can be weakened, and the fixed sleeve is provided with the convex part, so that the convex part can play a role in stabilizing the peripheral wall of the movable sleeve.

The positioning part is tightly propped against the inner peripheral wall of the handle sleeve to limit the handle sleeve to move downwards, and in order to improve the downward stability of the positioning part for limiting the handle sleeve, a first positioning groove is formed in the handle sleeve, and the positioning part can be buckled in the first positioning groove, so that the front surface of the positioning part is propped against the top wall of the first positioning groove. The locating part is buckled in the first locating groove, and the effect of resisting the glove is better.

The unlocking structure can have various structural forms, and is simple in structure, the movable sleeve is provided with an avoidance opening which can be used for accommodating the positioning part, the avoidance opening is positioned below the locking structure, and the avoidance opening is the unlocking structure. When the positioning part swings into the avoiding opening, the resistance of the positioning part to the handle sleeve disappears, and the handle sleeve can move downwards to perform injection.

In order to enable the positioning part to swing into the avoiding opening, the front surface of the positioning part is provided with a first inclined surface with the wall thickness gradually thicker along the downward moving direction of the handle sleeve. Therefore, when the avoiding opening is aligned with the positioning part in the radial direction of the pipe body, the handle sleeve is pressed downwards, and the extending arm swings towards the direction of the movable sleeve due to the action of the first inclined surface, so that the positioning part enters the avoiding opening, and the positioning part can be used for positioning the handle sleeve and continuously moving downwards to perform injection.

In order to enable the handle sleeve to be incapable of moving up and down after injection is completed, a second positioning groove is further formed in the handle sleeve and located right above the first positioning groove, the second positioning groove faces the avoidance opening in the radial direction of the tube body in the state that the piston moves to the bottom of the needle tube, and the positioning part is buckled in the second positioning groove. In the injection process, the positioning part of the positioning piece is always in an inward swinging state because the positioning part is extruded by the inner wall of the handle sleeve, when the second positioning groove faces the avoidance opening on the movable sleeve in the radial direction of the pipe body, the extrusion of the handle sleeve to the positioning part disappears, the positioning part swings to a natural vertical extending state, the positioning part is buckled in the second positioning groove at the moment, the positioning effect is realized on the handle sleeve, and the handle sleeve cannot move up and down.

In order to prevent the needle from being injured by the puncture due to the fact that the movable sleeve moves upwards after injection is completed, the pipe body is provided with a limiting piece, and the limiting piece is located on a path of upward movement of the movable sleeve when the piston is located at the bottom of the needle tube and the movable sleeve is located at the lower limit position. After the injection is completed, the limiting piece limits the movable sleeve to move upwards.

The structure is simple, the limiting piece comprises a connecting arm and a limiting part, the connecting arm extends along the axial line direction of the pipe body, the upper end of the connecting arm is connected with the pipe body, the lower end of the connecting arm is connected with the limiting part, the connecting arm can swing radially relative to the pipe body, and in the state that the piston is positioned at the bottom of the needle tube and the movable sleeve is positioned at the lower limit position, the limiting part is positioned right above the movable sleeve.

Before injection is completed, the movable sleeve can extrude the limiting part to the connecting arm to swing outwards, after injection is completed and the movable sleeve moves downwards, the connecting arm can resume swinging until the limiting part is positioned right above the movable sleeve, but the requirement is also met that the limiting part cannot interfere the downward movement of the handle sleeve, so that the handle sleeve is provided with a vertically extending strip-shaped groove, and the limiting part can be positioned in the strip-shaped groove and can generate relative displacement between the two; the top of the movable sleeve is provided with an elastic arm which can swing radially relative to the movable sleeve;

The limiting part is positioned in the strip-shaped groove in a state that the piston is positioned at the middle part of the needle tube; when the movable sleeve is positioned at the upper limit position and the piston is positioned at the bottom of the needle tube, the front surface of the limiting part is propped against the inner peripheral wall at the upper end of the strip-shaped groove, and the back surface of the limiting part is propped against the elastic arm of the movable sleeve; and in the state that the piston is positioned at the bottom of the needle tube and the movable sleeve is positioned at the lower limit position, the front surface of the limiting part is propped against the inner peripheral wall at the upper end of the strip-shaped groove, and the limiting part is positioned right above the movable sleeve. Before injection is completed, the limiting part is positioned in the strip-shaped groove, so that interference can not be generated on the upward movement of the movable sleeve; when the piston moves to the bottom of the needle tube and injection is completed, the limiting part is positioned above the strip-shaped groove, and at the moment, the limiting part is extruded by the inner peripheral wall of the handle sleeve, the connecting arm swings inwards, and the elastic arm of the movable sleeve is extruded by the limiting part to swing inwards; when the injector is removed from the skin, the movable sleeve moves downwards under the action of the elastic piece, but the limiting part is still in a state of being extruded by the inner peripheral wall of the handle sleeve and the connecting arm swings inwards, and at the moment, the limiting part is positioned right above the movable sleeve to limit the movable sleeve to move upwards.

Before the injection begins, a certain distance exists between the piston and the lower end of the piston rod, when the handle sleeve is pressed downwards after being unlocked, the piston rod is easy to suddenly and axially move, the use feeling is poor, the injection speed is too high, the lower end of the piston rod is provided with a damping block, the outer peripheral wall of the damping block is tightly contacted with the inner peripheral wall of the needle tube, and the damping block can move up and down along the needle tube along with the piston rod. The damping block has the function of adding damping to the downward movement of the piston rod and relieving the excessive speed of the piston rod during the initial movement.

The movable sleeve is equivalent to an actuating piece, and when injection is needed, the handle sleeve is unlocked by pressing the movable sleeve, so that the injection component is used for injecting liquid medicine. However, if the syringe falls onto a hard surface (e.g., if the user drops the device onto the floor), the holster is likely to move due to the impact, thereby triggering the injection assembly and wasting the medical fluid.

If the syringe is disposable, the user has not yet used the syringe, and the syringe is already discarded, and a new syringe must be purchased again, resulting in a waste of money and syringes; if the syringe is reusable, it must be refilled to deliver a new medicament, resulting in waste of the fluid. Preferably, the lower extreme detachably of body lid is equipped with the cap body, be equipped with the first support arm of axial extension on the cap body, the inside of movable sleeve is equipped with the second support arm that axial extension and link to each other rather than, and the top of second support arm can the cartridge in fixed cover, be equipped with the fender portion that can offset with the top of second support arm on the fixed cover under the state that the cap body lid was established on the body, the second support arm is extruded between first support arm and fixed cover, and the second support arm offsets with fender portion. The first support arm is arranged on the cap body, the second support arm is arranged on the movable sleeve, and the first support arm extrudes the second support arm to enable the second support arm to be propped against the blocking part of the fixed sleeve in the state that the cap body is covered on the tube body, so that the movable sleeve is limited to move upwards, the movable sleeve is prevented from moving upwards under the unnecessary condition (when the movable sleeve does not work for injection), and the injection assembly is triggered to cause the waste of liquid medicine or the rejection of the injection device; the first support arm can release the extrusion to the second support arm under the state that the cap body is dismantled from the body, makes the second support arm release and is bound by the fender portion, and the movable sleeve can upwards move and make the syringe work normally.

In order to ensure that the movable sleeve can smoothly move upwards after the first support arm does not press the second support arm, the top of the second support arm is provided with a second inclined plane which is inclined outwards from top to bottom, the inner peripheral wall of the fixed sleeve is provided with a third inclined plane which is inclined outwards from top to bottom, the third inclined plane can prop against the second inclined plane, the third inclined plane is a blocking part and moves on the movable sleeve, and the second support arm can swing inwards by an angle of movement due to the action of the third inclined plane so as to avoid interference of the blocking part.

Compared with the prior art, the invention has the advantages that: according to the invention, the handle sleeve is arranged, so that after the movable sleeve is propped against the skin, the handle sleeve is pressed downwards, the injection of liquid medicine can be realized, the injector is not required to be held during the injection, only the movable sleeve is required to prop against the skin, the handle sleeve is required to be grabbed to be pressed downwards, the requirement on the hand gesture of operating the injector during the injection is low, and the use is convenient; the syringe is not held by the palm and the piston rod is pushed by the thumb to perform injection, so that the length and the diameter of the needle tube can be larger, and the drug loading amount is larger; in addition, since the injection is performed by pressing the handle cover, the injection speed and the injection amount can be controlled, and the injection can be stopped at any time and midway during the injection process, and the liquid medicine does not leak.

Drawings

FIG. 1 is a schematic view of an embodiment of the present invention (a cap is mounted on a tube);

FIG. 2 is a cross-sectional view of FIG. 1 (semi-cut away from the positioning member);

FIG. 3 is another cross-sectional view of FIG. 1 (semi-section at the self-limiting feature);

FIG. 4 is another cross-sectional view of FIG. 1 (half-section from the second arm of the sleeve);

FIG. 5 is a schematic view of the structure of FIG. 1 with the cap and outer cover removed;

FIG. 6 is a schematic view of the tube body in FIG. 5;

FIG. 7 is a schematic view of the tube of FIG. 5 in another orientation;

FIG. 8 is a schematic view of the inner tube of FIG. 2;

FIG. 9 is a schematic view of the movable sleeve of FIG. 5;

FIG. 10 is a cross-sectional view of FIG. 9;

FIG. 11 is an exploded view of FIG. 1 (cap removed from tube);

FIG. 12 is a cross-sectional view of FIG. 11 (semi-cut away from the positioning member);

FIG. 13 is a schematic view of the movable sleeve of FIG. 1 being moved up (the relief opening facing the positioning portion of the positioning member);

FIG. 14 is a cross-sectional view of FIG. 13 (semi-cut away from the positioning member);

FIG. 15 is a cross-sectional view of the handle sleeve of FIG. 13 pressed downwardly (semi-section at the self-locating feature);

FIG. 16 is a schematic view of the handle sleeve of FIG. 15 moved to a lower limit position;

FIG. 17 is a cross-sectional view of FIG. 16 (semi-cut away from the positioning member);

FIG. 18 is another cross-sectional view of FIG. 16 (semi-section at the self-limiting feature);

FIG. 19 is a schematic view of the reset structure of the movable sleeve of FIG. 16;

FIG. 20 is a cross-sectional view (semi-section at the self-positioning element) of FIG. 19;

Fig. 21 is another cross-sectional view (semi-section at the self-limiting member) of fig. 19.

Detailed Description

The invention is described in further detail below with reference to the embodiments of the drawings.

As shown in fig. 1 to 21, the syringe of the present preferred embodiment comprises a tube body 1, a fixed sleeve 2, an injection assembly, a movable sleeve 4, a handle sleeve 5, an elastic member 6, and a cap body 8.

The pipe body 1 is vertically arranged, two ends of the pipe body are open, and the fixing sleeve 2 is vertically arranged in the pipe body 1 and is fixed relative to the pipe body 1. In this embodiment, the pipe body 1 and the fixed sleeve 2 are integrally formed through the connecting portion 10, and the movable sleeve 4 is provided with an avoiding groove 45 extending downward from the top thereof to avoid the connecting portion 10, and of course, the pipe body 1 and the fixed sleeve 2 may be assembled.

As shown in fig. 2, the injection assembly comprises a needle tube 71, a piston 72, a piston rod 73 and a needle head 74, wherein the needle tube 71 is fixedly arranged in the fixed sleeve 2 in a penetrating manner, the piston 72 is arranged in the needle tube 71 and can move up and down relative to the needle tube 71, the lower end of the piston rod 73 is inserted into the needle tube 71 and can abut against the upper end face of the piston 72, the piston rod 73 can move up and down along the needle tube 71, and the needle head 74 is connected with the lower end of the needle tube 71 and extends out of the tube body 1.

Before the injection starts, a certain distance exists between the piston 72 and the lower end of the piston rod 73, when the piston rod 73 starts to move downwards, the piston rod 73 is easy to suddenly and axially move, the use feeling is poor, and the injection speed is too high, so the damping block 75 is arranged at the lower end of the piston rod 73, the outer peripheral wall of the damping block 75 is tightly contacted with the inner peripheral wall of the needle tube 71, and the damping block 75 can move up and down along the needle tube 71 along with the piston rod 73. The damping block 75 may be a rubber block that acts to add damping to the downward movement of the piston rod 73, relieving the piston rod 73 from excessive speed during initial movement.

As shown in fig. 12, the movable sleeve 4 is sleeved on the fixed sleeve 2, the movable sleeve 4 is located between the fixed sleeve 2 and the pipe body 1, the lower end of the movable sleeve 4 can extend out of the pipe body 1 and hide the needle 74 in, the movable sleeve 4 moves upwards relative to the fixed sleeve 2 when being pressed by skin, and the elastic piece 6 acts on the movable sleeve 4, so that the movable sleeve 4 always keeps a downward movement trend. In this embodiment, the elastic member 6 is a spring, the upper end of which abuts against the connecting portion 10 of the fixed sleeve, and the lower end of which abuts against the connecting wall 40 connecting the movable sleeve 4 and the second arm 44 below.

A limiting groove 41 extending vertically is formed in the peripheral wall of the movable sleeve 4, a positioning block 21 is arranged on the peripheral wall of the fixed sleeve 2, the positioning block 21 is positioned in the limiting groove 41, and when the movable sleeve 4 moves downwards to the position that the top wall of the limiting groove 41 abuts against the positioning block 21, the movable sleeve 4 moves to the lower limit position, as shown in fig. 12; when the movable sleeve 4 moves upward to the point where the connecting portion 10 abuts against the bottom wall of the escape groove 15, the movable sleeve 4 moves to the upper limit position as shown in fig. 17.

The handle sleeve 5 is sleeved at the upper end of the tube body 1 and can move up and down relative to the tube body 1, the handle sleeve 5 is connected with the upper end of the piston rod 73, and when the handle sleeve 5 is pressed downwards, the piston rod 73 moves downwards to push the piston 72 to inject liquid medicine.

As shown in fig. 6 and 8, a guide block 11 is arranged on the outer peripheral wall of the pipe body 1, a guide groove 51 is arranged on the inner peripheral wall of the handle sleeve 5, the guide block 11 can be placed in the guide groove 51 and slide along the guide groove 51, the guide groove 51 vertically extends, and the guide block 11 and the guide groove 51 are matched so that the handle sleeve 5 can only move up and down. Of course, the guide groove can also be arranged on the pipe body 1, and the guide block is arranged on the handle sleeve 5. The above object is also achieved by such a structure.

When injecting, holding the handle sleeve 5 to press the movable sleeve 4 against the skin and downwards, so that the needle 74 penetrates into the skin, then pressing the handle sleeve 5 downwards to inject liquid medicine, but in order to prevent the needle 74 from penetrating into the skin, the handle sleeve 5 moves downwards to inject, the pipe body 1 is provided with the positioning piece 12, the positioning piece 12 extends along the axial line direction of the pipe body 1, and the positioning piece 12 can swing along the radial direction of the pipe body 1 to a first position which abuts against the handle sleeve 5 to limit the handle sleeve 5 to move downwards or a second position which is far away from the handle sleeve 5 to allow the handle sleeve 5 to move; the movable sleeve 4 is provided with a locking structure capable of positioning the positioning piece 12 at the first position and an unlocking structure allowing the positioning piece 12 to move to the second position, and the locking structure is positioned above the unlocking structure.

As shown in fig. 2, 4 and 6, in the present embodiment, the positioning member 12 includes an extension arm 121 and a positioning portion 122, the extension arm 121 extends along the axial line direction of the pipe body 1, a first through hole 13 is formed in the peripheral wall of the pipe body 1, the upper end of the extension arm 121 is connected to the top wall of the first through hole 13, the lower end is connected to the positioning portion 122, the positioning portion 122 is located in the first through hole 13, and the extension arm 121 can swing radially relative to the pipe body 1. The outer peripheral wall of the fixed sleeve 2 is convexly provided with a convex part 20, the front surface (i.e. the outer surface) of the positioning part 122 is propped against the handle sleeve 5 in the state that the positioning piece 12 is positioned at the first position, the back surface (i.e. the inner surface) of the positioning part 122 is propped against the outer peripheral wall of the movable sleeve 4, the inner peripheral wall of the movable sleeve 4 is propped against the convex part 20, and the outer peripheral wall of the movable sleeve 4 is a locking structure. In this embodiment, the handle sleeve 5 is provided with the first positioning groove 52, and the positioning portion 122 can be fastened in the first positioning groove 52, so that the front surface of the positioning portion 122 abuts against the top wall of the first positioning groove 52, and the front surface of the positioning portion 122 has the first inclined surface 1221 with gradually thicker wall thickness along the downward moving direction of the handle sleeve 5.

As shown in fig. 2, before the movable sleeve 4 moves to the point where the needle 74 pierces the skin, the outer peripheral wall of the movable sleeve 4 presses the positioning portion 122 outwardly against the handle sleeve 5 (i.e., the locking structure positions the positioning member 12 in the first position), at which time the handle sleeve 5 cannot move downward for injection;

As shown in fig. 15, the movable sleeve 4 is provided with an avoidance port 42 in which the positioning portion 122 is accommodated, the avoidance port 42 is located below the locking structure, and the avoidance port 42 is an unlocking structure. After the needle 74 pierces the skin, the movable sleeve 4 moves up to the avoiding opening 42, i.e. it will face the positioning portion 122, and the handle sleeve 5 is pressed downward, because of the action of the first inclined surface 1221, the extension arm 121 swings towards the direction of the movable sleeve 4, so that the positioning portion 122 enters the avoiding opening 42 (at this time, the unlocking structure moves the positioning member 12 to the second position), at this time, the positioning of the handle sleeve 5 by the positioning portion 122 disappears, and the handle sleeve 5 can move downward for injection.

As shown in fig. 17, the handle sleeve 5 is further provided with a second positioning groove 53 located right above the first positioning groove 52, and when the piston 72 moves to the bottom of the needle tube 71, the second positioning groove 53 faces the avoiding opening 42 in the radial direction of the tube 1, and the positioning portion 122 is locked in the second positioning groove 53 under the restoring force of the extension arm 121 itself. Specifically, during the injection process, the positioning portion 122 of the positioning member 12 is always in an inward swinging state because it is pressed by the inner wall of the handle sleeve 5, when the second positioning groove 53 faces the avoiding opening 42 on the movable sleeve 4 in the radial direction of the tube body 1, the pressing of the handle sleeve 5 to the positioning portion 122 disappears, the extending arm 121 swings to a state of natural vertical extension, the positioning portion 122 is buckled in the second positioning groove 53 at this time, and because the movable sleeve 4 moves downward under the action of the elastic member 6 after being separated from the skin, at this time, the avoiding opening 42 on the movable sleeve 4 is located below the positioning portion 122, namely, at this time, the peripheral wall of the movable sleeve 4 abuts against the back surface of the positioning portion 122 (as shown in fig. 20), and the handle sleeve 5 cannot move upward; and because after injection is completed, the piston 72 abuts against the bottom of the needle tube 71, the handle sleeve 5 is fixedly connected with the piston rod 73, and the needle tube 71 plays a role in limiting the downward movement of the handle sleeve 5.

As shown in fig. 3, 6, 8 and 9, the pipe body 1 is provided with a limiting member 14, the limiting member 14 includes a connecting arm 141 and a limiting portion 142, the peripheral wall of the pipe body 1 is provided with a second through hole 15, the connecting arm 141 extends along the axial line direction of the pipe body 1, the upper end of the connecting arm 141 is connected with the top wall of the second through hole 15, the lower end of the connecting arm 141 is connected with the limiting portion 142, the limiting portion 142 is located in the second through hole 15, and the connecting arm 141 can swing radially relative to the pipe body 1.

The handle sleeve 5 is provided with a vertically extending strip-shaped groove 54, and the limiting part 142 can be positioned in the strip-shaped groove 54 and can generate relative displacement between the two; the top of the movable sleeve 4 is provided with an elastic arm 43 capable of swinging radially with respect thereto.

As shown in fig. 3, in a state in which the piston 72 is located at the middle portion of the needle tube 71, the stopper 142 is located at a position at the middle lower portion of the bar-shaped groove 54; before the injection is completed, the limiting part 142 is positioned in the strip-shaped groove 54, and does not interfere with the upward movement of the movable sleeve 4.

As shown in fig. 18, in a state where the movable sleeve 4 is positioned at the upper limit position and the piston 72 is positioned at the bottom of the needle tube 71, the front surface of the limiting portion 142 abuts against the inner peripheral wall of the upper end of the bar-shaped groove 54, the back surface of the limiting portion 142 abuts against the elastic arm 43 of the movable sleeve 4, and the limiting portion 142 presses the elastic arm 43 of the movable sleeve 4 to swing inward;

As shown in fig. 21, when the injector is removed from the skin, in a state that the piston 72 is located at the bottom of the needle tube 71 and the movable sleeve 4 is located at the lower limit position, the movable sleeve 4 moves downward under the action of the elastic member 6, but the limiting portion 142 is still pressed by the inner peripheral wall of the handle sleeve 5 and the connecting arm 141 swings inward, that is, the front surface of the limiting portion 142 abuts against the inner peripheral wall of the upper end of the bar-shaped groove 54, and at this time, the limiting portion 142 is located directly above the movable sleeve 4, that is, the limiting member 14 is located on the upward moving path of the movable sleeve 4, so as to limit the upward movement of the movable sleeve 4, thereby preventing the needle 74 from being pricked by exposure.

As shown in fig. 4, the lower end of the pipe body 1 is detachably covered with a cap body 8, the cap body 8 is provided with a first support arm 81 extending axially, the inside of the movable sleeve 4 is provided with a second support arm 44 extending axially and connected with the first support arm, the top of the second support arm 44 is provided with a second inclined surface 441 inclining outwards from top to bottom, the top of the second support arm 44 can be inserted into the fixed sleeve 2, the fixed sleeve 2 is provided with a blocking part capable of propping against the top of the second support arm 44, and the blocking part is a third inclined surface 22 inclining outwards from top to bottom and arranged on the inner peripheral wall of the fixed sleeve 2.

In the state that the cap body 8 is covered on the tube body 1, the second support arm 44 is extruded between the first support arm 81 and the fixed sleeve 2, and the second support arm 44 abuts against the blocking part, so that the movable sleeve 4 is limited to move upwards, and the movable sleeve 4 is prevented from moving upwards under the optional condition (when the injector does not work), and further the injection assembly is triggered to cause the waste of liquid medicine or the rejection of the injection device.

As shown in fig. 12 and 14, in the state that the cap 8 is detached from the tube 1, the first arm 81 can release the extrusion of the second arm 44, so that the second arm 44 is released from being bound by the blocking portion, the movable sleeve 4 can move upward, and during the upward movement of the movable sleeve 4, the second arm 44 can swing inward by a certain angle due to the action of the third inclined surface 22, so as to avoid the interference of the blocking portion, and ensure that the movable sleeve 4 can move upward smoothly.

As shown in fig. 2 and 8, in this embodiment, the handle sleeve 5 includes an outer sleeve 55 and an inner tube 56, the top of the outer sleeve 55 is closed and sleeved on the inner tube 56, the first positioning groove 52, the second positioning groove 53 and the strip-shaped groove 54 are all formed by matching a through hole formed on the inner tube 56 with the inner wall surface of the outer sleeve 55, so that the groove is formed on the inner wall surface of the handle sleeve 5, and the guiding groove 51 is formed on the inner wall surface of the inner tube 56.

The working procedure of the injector of this embodiment is as follows:

1. in the initial state, as shown in fig. 2, 3 and 4, the cap body 8 is covered on the pipe body 1, the second support arm 44 is pressed between the first support arm 81 and the fixed sleeve 2, and the movable sleeve 4 cannot move upwards; the positioning part 122 of the positioning piece 12 is positioned in the first positioning groove 52 and is extruded by the outer peripheral wall of the movable sleeve 4, the inner peripheral wall of the movable sleeve 4 is propped against the convex part 20, and the handle sleeve 5 cannot move downwards; the limiting part 142 of the limiting piece 14 is positioned at the lower part of the strip-shaped groove 54; the lower end of the movable sleeve 4 extends out of the pipe body 1 and conceals the needle 74 inside;

2. the cap 8 is removed, as shown in fig. 12, the first arm 81 can release the extrusion of the second arm 44, and other states are the same as the initial state;

3. As shown in fig. 14, the movable sleeve 4 is pressed against the skin, the movable sleeve 4 moves upwards, the needle 74 gradually pierces the skin, and the second arm 44 swings inwards, at this time, because the positioning portion 122 is positioned in the first positioning groove 52, the handle sleeve 5 cannot move downwards relative to the tube body 1, and the movable sleeve 4 moves to the avoiding opening 42 to be opposite to the positioning portion 122 of the positioning member 12 in the radial direction of the tube body 1;

4. as shown in fig. 15, pressing the handle cover 5 downward, the piston rod 73 moves downward, the extension arm 121 of the stopper 12 swings inward until the positioning portion 122 is disengaged from the first positioning groove 52 and moves into the escape opening 42, and the damping block 75 on the piston rod 73 contacts the piston 72; during the downward movement of the handle sleeve 5, the position of the limiting part 142 of the limiting part 14 in the bar-shaped groove 54 is also raised;

5. as shown in fig. 17 and 18, the handle sleeve 5 is continuously pressed downwards, the piston 72 moves downwards to inject the liquid medicine until the positioning part 122 of the positioning piece 12 faces the second positioning groove 53 in the radial direction of the tube body 1 and is buckled in the second positioning groove 53, the handle sleeve 5 cannot move upwards, the piston 72 is positioned at the bottom of the needle tube 71, the injection is completed, and the handle sleeve 5 cannot move downwards because of the limit function of the needle tube 71 on the piston 72; the limiting part 142 of the limiting part 14 is extruded by the inner wall at the upper end of the bar-shaped groove 54 to swing inwards, the limiting part 142 extrudes the elastic arm 43 of the movable sleeve 4 to swing inwards, otherwise, the limiting part 142 interferes with the movable sleeve 4, so that the movable sleeve 4 cannot move upwards;

6. As shown in fig. 20 and 21, the syringe is removed from the skin, the movable sleeve 4 moves downward to the lower limit position under the action of the elastic member 6, the limiting part 142 is still pressed by the inner peripheral wall at the upper end of the bar-shaped groove 54, and the connecting arm 141 swings inward, and at this time, the limiting part 142 is located right above the movable sleeve 4, so as to limit the upward movement of the movable sleeve 4, and prevent the needle 74 from being injured by the user due to exposure.

In the above, the "inner" refers to a direction approaching the axis of the tube body 1, and the "outer" refers to a direction separating from the axis of the tube body 1. As described above, the injector according to the present embodiment has few components, is convenient to use, and can control the injection speed and the injection amount.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for purposes of describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and because the disclosed embodiments of the present invention may be arranged in different orientations, these directional terms are merely for illustration and should not be construed as limitations, such as "upper", "lower" are not necessarily limited to orientations opposite or coincident with the direction of gravity.

Claims

1. An injector, comprising

The pipe body (1) is vertically arranged and is open at two ends;

the fixing sleeve (2) is vertically arranged in the pipe body (1) and is fixed relative to the pipe body (1);

The injection assembly comprises a needle tube (71), a piston (72), a piston rod (73) and a needle head (74), wherein the needle tube (71) is fixedly arranged in a fixed sleeve (2) in a penetrating mode, the piston (72) is arranged in the needle tube (71) and can move up and down relative to the needle tube (71), the lower end of the piston rod (73) is inserted into the needle tube (71) and can abut against the upper end face of the piston (72), the piston rod (73) can move up and down along the needle tube (71), and the needle head (74) is connected with the lower end of the needle tube (71) and extends out of the tube body (1);

The movable sleeve (4) is arranged between the fixed sleeve (2) and the pipe body (1), the lower end of the movable sleeve (4) can extend out of the pipe body (1) and hide the needle head (74) in the pipe body, and the movable sleeve (4) moves upwards relative to the fixed sleeve (2) when being pressed;

The elastic piece (6) acts on the movable sleeve (4) to enable the movable sleeve (4) to always keep a downward movement trend;

The device is characterized by further comprising a handle sleeve (5) which is sleeved at the upper end of the pipe body (1) and can move up and down relative to the pipe body (1), wherein the handle sleeve (5) is connected with the upper end of the piston rod (73);

The pipe body (1) is provided with a positioning piece (12), the positioning piece (12) extends along the axial line direction of the pipe body (1), and the positioning piece (12) can swing along the radial direction of the pipe body (1) to a first position propped against the handle sleeve (5) to limit the handle sleeve (5) to move downwards or a second position far away from the handle sleeve (5) to allow the handle sleeve (5) to move; the movable sleeve (4) is provided with a locking structure capable of positioning the positioning piece (12) at a first position and an unlocking structure allowing the positioning piece (12) to move to a second position, and the locking structure is positioned above the unlocking structure;

The positioning piece (12) comprises an extension arm (121) and a positioning part (122), the extension arm (121) extends along the axial line direction of the pipe body (1), one end of the extension arm (121) is connected with the pipe body (1), the other end of the extension arm is connected with the positioning part (122), the extension arm (121) can swing radially relative to the pipe body (1), the front surface of the positioning part (122) is propped against the handle sleeve (5) when the positioning piece (12) is in a first position, the back surface of the positioning part (122) is propped against the peripheral wall of the movable sleeve (4), and the peripheral wall of the movable sleeve (4) is the locking structure;

The outer peripheral wall of the fixed sleeve (2) is convexly provided with a convex part (20), the pipe body (1) and the fixed sleeve (2) are integrally connected through a connecting part (10), the movable sleeve (4) is provided with an avoidance groove (45) which extends downwards from the top of the movable sleeve to avoid the connecting part (10), the outer peripheral wall of the movable sleeve (4) is propped against the back surface of the positioning part (122) when the positioning piece (12) is positioned at the first position, and the inner peripheral wall of the movable sleeve (4) is propped against the convex part (20);

the handle sleeve (5) is provided with a first positioning groove (52), and the positioning part (122) can be buckled in the first positioning groove (52), so that the front surface of the positioning part (122) is propped against the top wall of the first positioning groove (52);

An avoidance opening (42) in which the positioning part (122) can be accommodated is formed in the movable sleeve (4), the avoidance opening (42) is positioned below the locking structure, and the avoidance opening (42) is the unlocking structure.

2. The syringe of claim 1, wherein: the front surface of the positioning part (122) is provided with a first inclined surface (1221) with gradually thicker wall thickness along the downward moving direction of the handle sleeve (5).

3. The syringe of claim 1, wherein: the handle sleeve (5) is also provided with a second positioning groove (53) which is positioned right above the first positioning groove (52), the second positioning groove (53) faces the avoidance opening (42) in the radial direction of the pipe body (1) under the state that the piston (72) moves to the bottom of the needle tube (71), and the positioning part (122) is buckled in the second positioning groove (53).

4. A syringe according to any one of claims 1 to 3, wherein: the lower end of the piston rod (73) is provided with a damping block (75), the outer peripheral wall of the damping block (75) is tightly contacted with the inner peripheral wall of the needle tube (71), and the damping block (75) can move up and down along the needle tube (71) along with the piston rod (73).

5. A syringe according to any one of claims 1 to 3, wherein: the pipe body (1) is provided with a limiting piece (14), and the limiting piece (14) is positioned on a path of upward movement of the movable sleeve (4) under the state that the piston (72) is positioned at the bottom of the needle tube (71) and the movable sleeve (4) is positioned at the lower limit position.

6. The syringe of claim 5, wherein: the limiting piece (14) comprises a connecting arm (141) and a limiting part (142), the connecting arm (141) extends along the axial line direction of the pipe body (1), one end of the connecting arm (141) is connected with the pipe body (1), the other end of the connecting arm is connected with the limiting part (142), the connecting arm (141) can swing radially relative to the pipe body (1), and in the state that the piston (72) is located at the bottom of the needle tube (71) and the movable sleeve (4) is located at the lower limit position, the limiting part (142) is located right above the movable sleeve (4).

7. The syringe of claim 6, wherein: the handle sleeve (5) is provided with a vertically extending strip-shaped groove (54), and the limiting part (142) can be positioned in the strip-shaped groove (54) and can generate relative displacement between the two; the top of the movable sleeve (4) is provided with an elastic arm (43) which can swing radially relative to the movable sleeve;

The limiting part (142) is positioned in the strip-shaped groove (54) in a state that the piston (72) is positioned at the middle part of the needle tube (71); in a state that the movable sleeve (4) is positioned at the upper limit position and the piston (72) is positioned at the bottom of the needle tube (71), the front surface of the limiting part (142) is propped against the inner peripheral wall at the upper end of the strip-shaped groove (54), and the back surface of the limiting part (142) is propped against the elastic arm (43) of the movable sleeve (4); in the state that the piston (72) is positioned at the bottom of the needle tube (71) and the movable sleeve (4) is positioned at the lower limit position, the front surface of the limiting part (142) is propped against the inner peripheral wall at the upper end of the strip-shaped groove (54), and the limiting part (142) is positioned right above the movable sleeve (4).

8. A syringe according to any one of claims 1 to 3, wherein: the lower extreme detachably lid of body (1) is equipped with cap body (8), be equipped with axially extending's first support arm (81) on cap body (8), the inside of movable sleeve (4) is equipped with axially extending and rather than continuous second support arm (44), and the top of second support arm (44) can cartridge in fixed cover (2), be equipped with the fender portion that can offset with the top of second support arm (44) on fixed cover (2) under cap body (8) lid established the state on body (1), second support arm (44) are extruded between first support arm (81) and fixed cover (2), and the top and the fender portion of second support arm (44) offset.

9. The syringe of claim 8, wherein: the top of the second support arm (44) is provided with a second inclined plane (441) which is inclined outwards from top to bottom, the inner peripheral wall of the fixed sleeve (2) is provided with a third inclined plane (22) which is inclined outwards from top to bottom, the third inclined plane (22) can prop against the second inclined plane (441), and the third inclined plane (22) is the blocking part.