Medicine pushing structure used in rotary injector

Abstract

The medicine pushing structure comprises a pen container and a pen refill which is arranged in the pen container and contains medicine liquid, a fixing piece is fixed in the pen container, a rotating piece which can rotate relative to the fixing piece is arranged on the fixing piece, the rotating piece is in threaded connection with a screw rod, and the screw rod is connected with a screw rod. One end of the screw rod is connected with a sealing piston capable of pushing out liquid medicine in the pen refill, a clutch rod, an elastic piece arranged between the clutch rod and the pen container and a damping structure arranged between the clutch rod and the pen container and used for providing resistance when the clutch rod rotates relative to the pen container are further arranged in the pen container, and the clutch rod is provided with a foremost position and a rearmost position. The clutch rod can overcome the resistance of the damping structure and rotationally compress the elastic piece when located at the last position, and the clutch rod is separated from the damping structure and arranged on the rotating piece in a sleeving mode when located at the foremost position so that the elastic piece can reset to drive the rotating piece to synchronously rotate; a locking ring which synchronously rotates with the clutch rod and is in threaded connection with the screw rod is arranged in the clutch rod, so that the locking ring is propped against the tail end of the screw rod to limit the rotation of the clutch rod when the liquid medicine in the refill is completely pushed; by the adoption of the structure, the situation that when a user injects medicine, the user does not have much liquid medicine clearly, but the user mistakenly considers that much liquid medicine is injected can be avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of syringes, in particular to a medicine pushing structure for a rotary syringe. Background Art

[0002] When most injection pens for drugs such as insulin on the market preset the injection amount of the drug, they are adjusted by rotating a knob. However, the existing problem is that when the liquid medicine in the injection pen is insufficient or completely emptied, the knob can still rotate. Although the existing injection pens can view the remaining liquid medicine through a transparent window, if the user does not pay attention, it is easy to cause the situation that the user thinks the drug amount is sufficient but actually it is not. Content of the Utility Model

[0003] In view of this, the purpose of the utility model is to provide a medicine pushing structure for a rotary syringe. The locking ring moves a certain distance towards the tail end of the screw rod during each injection, and locks the clutch rod after the liquid medicine is injected completely.

[0004] The technical solution adopted by the utility model to solve its technical problems is to provide a medicine pushing structure for a rotary syringe, which includes a pen barrel and a pen core with liquid medicine arranged in the pen barrel. A fixing part is fixed in the pen barrel, and a rotating part capable of rotating relative to the fixing part is arranged on the fixing part. The rotating part is threadedly connected with a screw rod, and one end of the screw rod is connected with a sealing piston capable of pushing out the liquid medicine in the pen core. A clutch rod, an elastic part arranged between the clutch rod and the pen barrel, and a damping structure arranged between the clutch rod and the pen barrel for providing resistance when the clutch rod rotates relative to the pen barrel are further arranged in the pen barrel. The clutch rod has a foremost position and a rearmost position. When in the rearmost position, the clutch rod can overcome the resistance of the damping structure and rotate to compress the elastic part. When in the foremost position, the clutch rod disengages from the damping structure and is sleeved on the rotating part to enable the elastic part to reset and drive the rotating part to rotate synchronously. A locking ring that rotates synchronously with the clutch rod and is threadedly connected with the screw rod is arranged in the clutch rod, so that when the liquid medicine in the pen core is pushed out completely, the locking ring abuts against the tail end of the screw rod to limit the rotation of the clutch rod.

[0005] As a further improvement of the utility model, a pushing block is arranged between the sealing piston and the screw rod.

[0006] As a further improvement of the utility model, a fixed ratchet is arranged on the fixing part, and a rotating ratchet pawl cooperating with the fixed ratchet is arranged on the rotating part.

[0007] As a further improvement of the utility model, an annular fixing groove is arranged on the fixing part, and a rotating convex block clamped in the annular fixing groove is arranged on the rotating part.

[0008] As a further improvement of the present utility model, the outer peripheral surface of the fixing member is provided with a fixing groove arranged along the axial direction, and the inner side wall of the pen barrel is provided with a pen barrel convex block inserted into the fixing groove.

[0009] As a further improvement of the present utility model, the pen barrel includes a pen body and a pen core holder connected to one end of the pen body. The pen barrel convex block is arranged inside the pen body. The outer peripheral surface of the pen core holder is provided with a pen core holder groove, and the fixing member is provided with a fixing buckle clamped in the pen core holder groove. The fixing buckle is located between the pen body and the pen core holder.

[0010] As a further improvement of the present utility model, the inner side wall of the clutch rod is provided with a clutch groove, and the rotating member is provided with a transmission convex block capable of being inserted into the clutch groove. When in the foremost position, the transmission convex block is inserted into the clutch groove so that the clutch rod rotates synchronously with the rotating member.

[0011] As a further improvement of the present utility model, the inner side wall of the clutch rod is provided with a locking convex block arranged along the axial direction, and the locking ring is provided with a locking through groove for the locking convex block to be inserted into.

[0012] As a further improvement of the present utility model, the tail end of the screw rod is provided with a limiting block for the locking ring to abut against.

[0013] As a further improvement of the present utility model, the damping structure includes a plurality of rotating triangular teeth arranged on the clutch rod and a plurality of fixed triangular teeth arranged on the inner side wall of the pen barrel. The fixed triangular teeth are all provided with a first gentle slope and a first steep slope, and the rotating triangular teeth are all provided with a second gentle slope cooperating with the first gentle slope and a second steep slope cooperating with the first steep slope. When in the foremost position, the rotating triangular teeth are separated from the fixed triangular teeth.

[0014] The beneficial effects of the present utility model are at least as follows: When the user rotates the clutch rod, the clutch rod will continuously compress the elastic member. Under the action of the damping structure, the elastic member will not reset. Under the pressing of the user, the clutch rod will sleeved on the rotating member and disengage from the damping structure. The elastic member resets and drives the rotating member to rotate together, and drives the screw rod to push the liquid medicine forward to flow out. The advantage of synchronously rotating the locking ring with the clutch rod and threadedly connecting it with the screw rod is that when rotating the clutch rod to compress the elastic member, it will also drive the locking ring to move towards the tail end of the screw rod. When the liquid medicine is pushed out completely, the preset injection amount cannot be further increased, thereby avoiding the situation that when the user injects the medicine, although there is not so much liquid medicine, the user mistakenly thinks that he has injected so much liquid medicine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a structural cross-sectional view of the present utility model;

[0016] Figure 2 is Figure 1 the enlarged view of the partial view A in

[0017] Figure 3 is an exploded view of the structure of the main parts of the present utility model;

[0018] Figure 4 is a schematic structural view of the fixing member of the present utility model;

[0019] Figure 5 is a schematic structural view of the rotating member of the present utility model;

[0020] Figure 6 is a schematic structural view of the locking ring of the present utility model;

[0021] Figure 7 is a schematic structural view of the clutch lever of the present utility model. Specific embodiments

[0022] Next, the technical solution of the present utility model will be clearly and completely described in conjunction with the accompanying drawings.

[0023] Referring to Figures 1-7 , the present utility model provides a drug pushing structure for a rotary syringe, including a pen barrel 1 and a pen core 2 provided in the pen barrel 1 and containing liquid medicine. A fixing member 3 is fixed in the pen barrel 1. A rotating member 4 that can rotate relative to the fixing member 3 is provided on the fixing member 3. The rotating member 4 is threadedly connected to a screw rod 5. One end of the screw rod 5 is connected to a sealing piston 21 that can push the liquid medicine in the pen core 2 out. A clutch lever 6, an elastic member 7 provided between the clutch lever 6 and the pen barrel 1, and a damping structure 8 provided between the clutch lever 6 and the pen barrel 1 for providing resistance when the clutch lever 6 rotates relative to the pen barrel 1 are further provided in the pen barrel 1. The clutch lever 6 has a foremost position and a rearmost position. When in the rearmost position, the clutch lever 6 can overcome the resistance of the damping structure 8 and rotate to compress the elastic member 7. When in the foremost position, the clutch lever 6 disengages from the damping structure 8 and sleeves on the rotating member 4 to enable the elastic member 7 to reset and drive the rotating member 4 to rotate synchronously. A locking ring 9 that rotates synchronously with the clutch lever 6 and is threadedly connected to the screw rod 5 is provided in the clutch lever 6 so that when the liquid medicine in the pen core 2 is completely pushed out, the locking ring 9 abuts against the tail end of the screw rod 5 to limit the rotation of the clutch lever 6; when the user rotates the clutch lever 6, the clutch lever 6 will continuously compress the elastic member 7. Under the action of the damping structure 8, the elastic member 7 will not reset. When the user presses the clutch lever 6 to move to the foremost position, the clutch lever 6 will sleeve on the rotating member 4 and disengage from the damping structure 8. The elastic member 7 resets and drives the rotating member 4 to rotate together, and drives the screw rod 5 to push the liquid medicine forward to flow out. The advantage of making the locking ring 9 rotate synchronously with the clutch lever 6 and be threadedly connected to the screw rod 5 is that when the clutch lever 6 is rotated to compress the elastic member 7, the locking ring 9 will also be driven to move towards the tail end of the screw rod 5. When the liquid medicine is completely pushed out, the preset injection amount cannot be further increased, thereby avoiding the situation where the user thinks they have injected a certain amount of liquid medicine when there is actually not that much during drug injection.

[0024] As a specific implementation manner, the elastic member 7 is a torsion spring.

[0025] Referring to Figures 1-3 , a pushing block 51 is provided between the sealing piston 21 and the screw rod 5.

[0026] Referring to Figure 4 and Figure 5 , a fixed ratchet wheel 31 is provided on the fixing member 3, and a rotating ratchet pawl 41 cooperating with the fixed ratchet wheel 31 is provided on the rotating member 4, so that the rotating member 4 can only rotate unidirectionally relative to the fixing member 3 to prevent the screw rod 5 from moving backward.

[0027] Referring to Figure 4 and Figure 5 , an annular fixing groove 32 is provided on the fixing member 3, and a rotating convex block 42 clamped in the annular fixing groove 32 is provided on the rotating member 4.

[0028] Referring to Figure 2 and Figure 4 , an axially arranged fixing groove 33 is provided on the outer peripheral surface of the fixing member 3, and a pen barrel convex block inserted into the fixing groove 33 is provided on the inner side wall of the pen barrel 1; the fixing member 3 can be inserted into the pen barrel 1 to prevent the fixing member 3 from rotating and can achieve preliminary positioning.

[0029] Referring to Figure 1 and Figure 2 , the pen barrel 1 includes a pen body 11 and a pen core holder 12 connected to one end of the pen body 11. The pen barrel convex block is provided in the pen body 11. A pen core holder groove 121 is provided on the outer peripheral surface of the pen core holder 12. The fixing member 3 is provided with a fixing buckle 34 clamped in the pen core holder groove 121. The fixing buckle 34 is located between the pen body 11 and the pen core holder 12; clamping the fixing member 3 in the pen core holder 12 can achieve positioning and locking. The cooperation of the fixing groove 33 and the pen barrel convex block can achieve the effects of quick positioning and guiding, and setting the fixing buckle 34 between the pen body 11 and the pen core holder 12 can effectively lock the fixing member 3 to prevent the fixing member 3 from shifting.

[0030] Referring to Figures 1-7 , a clutch groove 61 is provided on the inner side wall of the clutch rod 6, and a transmission convex block 43 that can be inserted into the clutch groove 61 is provided on the rotating member 4. When in the foremost position, the transmission convex block 43 is inserted into the clutch groove 61 so that the clutch rod 6 rotates synchronously with the rotating member 4.

[0031] Referring to Figure 7 , a locking convex block 62 arranged axially is provided on the inner side wall of the clutch rod 6, and a locking through groove 91 for the locking convex block 62 to insert is provided on the locking ring 9; the locking ring 9 and the clutch rod 6 are rotated synchronously.

[0032] Referring to Figures 1-3 , a limiting block 52 for the locking ring 9 to abut against is provided at the tail end of the screw rod 5.

[0033] Referring to Figure 2 , the damping structure 8 includes a plurality of rotating triangular teeth 81 provided on the clutch rod 6 and a plurality of fixed triangular teeth 82 provided on the inner side wall of the pen barrel 1. The fixed triangular teeth 82 are each provided with a first gentle slope and a first steep slope. The rotating triangular teeth 81 are each provided with a second gentle slope that cooperates with the first gentle slope and a second steep slope that cooperates with the first steep slope. When in the foremost position, the rotating triangular teeth 81 disengage from the fixed triangular teeth 82; when rotating the clutch rod 6 to increase the injection volume, the first gentle slope and the second gentle slope cooperate, and the slope is small, so a relatively small force can be used to increase the injection volume. And each time the rotating triangular teeth 81 move through a fixed triangular tooth 82 is an increment. Under the action of the elastic member 7, the second steep slope will be attached to the first steep slope, so as to ensure that the injection volume increased by passing through each fixed triangular tooth 82 is accurate. When pressing the clutch rod 6 to drive the clutch rod 6 to move to the foremost position, the rotating triangular teeth 81 will disengage from the fixed triangular teeth 82, so that under the action of the elastic member 7, the clutch rod 6 will be driven to rotate back to its original position, driving the screw rod 5 to move forward to eject the liquid medicine.

Claims

1. A medicine pushing structure for a rotary syringe, characterized in that: The invention comprises a pen barrel (1) and a pen core (2) arranged in the pen barrel (1) and containing liquid medicine. A fixing part (3) is fixed in the pen barrel (1). A rotating part (4) capable of rotating relative to the fixing part (3) is arranged on the fixing part (3). The rotating part (4) is threadedly connected with a screw rod (5). One end of the screw rod (5) is connected with a sealing piston (21) capable of pushing out the liquid medicine in the pen core (2). The pen barrel (1) is also provided with a clutch rod (6), an elastic part (7) arranged between the clutch rod (6) and the pen barrel (1), and a spring (8) arranged between the clutch rod (6) and the pen barrel (1) for providing resistance when the clutch rod (6) rotates relative to the pen barrel (1). The damping structure (8) is provided, wherein the clutch rod (6) has a frontmost position and a rearmost position. When the clutch rod (6) is in the rearmost position, the clutch rod (6) can overcome the resistance of the damping structure (8) and rotate to compress the elastic member (7). When the clutch rod (6) is in the frontmost position, the clutch rod (6) is separated from the damping structure (8) and is sleeved on the rotating member (4) so ​​that the elastic member (7) is reset and drives the rotating member (4) to rotate synchronously. The clutch rod (6) is provided with a locking ring (9) which rotates synchronously with the clutch rod (6) and is threadedly connected to the screw rod (5) so that when the liquid medicine in the pen core (2) is exhausted, the locking ring (9) abuts against the tail end of the screw rod (5) to limit the rotation of the clutch rod (6).

2. A medicine pushing structure for a rotary syringe according to claim 1, characterized in that: A push block (51) is provided between the sealing piston (21) and the screw rod (5).

3. A medicine pushing structure for a rotary syringe according to claim 1, characterized in that: The fixing member (3) is provided with a fixing ratchet (31), and the rotating member (4) is provided with a rotating pawl (41) that cooperates with the fixing ratchet (31).

4. A medicine pushing structure for a rotary syringe according to claim 1, characterized in that: The fixing member (3) is provided with an annular fixing groove (32), and the rotating member (4) is provided with a rotating protrusion (42) which is clamped in the annular fixing groove (32).

5. The drug pushing structure for a rotary syringe according to claim 1, characterized in that: The outer peripheral surface of the fixing member (3) is provided with a fixing groove (33) arranged along the axial direction, and the inner side wall of the pen holder (1) is provided with a pen holder protrusion inserted into the fixing groove (33).

6. A medicine pushing structure for a rotary syringe according to claim 5, characterized in that: The pen holder (1) comprises a pen body (11) and a refill frame (12) connected to one end of the pen body (11); the pen holder protrusion is arranged in the pen body (11); the outer peripheral surface of the refill frame (12) is provided with a refill frame groove (121); the fixing member (3) is provided with a fixing buckle (34) clamped in the refill frame groove (121); the fixing buckle (34) is located between the pen body (11) and the refill frame (12).

7. The drug pushing structure for a rotary syringe according to claim 1, characterized in that: The inner side wall of the clutch rod (6) is provided with a clutch groove (61), and the rotating member (4) is provided with a transmission protrusion (43) capable of being inserted into the clutch groove (61). When located at the frontmost position, the transmission protrusion (43) is inserted into the clutch groove (61) so that the clutch rod (6) and the rotating member (4) rotate synchronously.

8. The drug pushing structure for a rotary syringe according to claim 1, characterized in that: The inner side wall of the clutch rod (6) is provided with a locking protrusion (62) arranged along the axial direction, and the locking ring (9) is provided with a locking through groove (91) for the locking protrusion (62) to be inserted.

9. The drug pushing structure for a rotary syringe according to claim 1, characterized in that: The rear end of the screw rod (5) is provided with a limit block (52) for the locking ring (9) to abut against.

10. The drug pushing structure for a rotary syringe according to claim 1, characterized in that: The damping structure (8) comprises a plurality of rotating triangular teeth (81) arranged on a clutch rod (6) and a plurality of fixed triangular teeth (82) arranged on the inner wall of the pen holder (1); the fixed triangular teeth (82) are each provided with a first gentle slope surface and a first steep slope surface; the rotating triangular teeth (81) are each provided with a second gentle slope surface cooperating with the first gentle slope surface and a second steep slope surface cooperating with the first steep slope surface; when located at the frontmost position, the rotating triangular teeth (81) are separated from the fixed triangular teeth (82).

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