Pressing type automatic injection pen

Abstract

The utility model discloses a push type automatic injection pen which comprises a pen body tube and a refill frame, a screw rod, a positioner and a clutch mechanism are arranged in the pen body tube, the positioner is fixedly connected to the pen body tube, the screw rod is in threaded connection with the positioner, and a transmission structure capable of enabling the clutch mechanism to rotate is further arranged in the pen body tube. The clutch mechanism has a joint state and a disengagement state, a spring is further arranged in the pen body tube, a knob sleeves the outer side of the spring, a damping structure is arranged between the pen body tube and the knob, a button is connected to the knob in a sliding mode, and the clutch mechanism is provided with a first spring which enables the clutch mechanism to be switched from the joint state to the disengagement state. The injection amount is adjusted by adjusting the compression degree of the clockwork spring through the knob, the clockwork spring is released by pressing the button, and the clutch mechanism is switched into a joint state, so that the screw rod automatically pushes the medicament refill for injection, the injection amount does not need to be controlled by continuously pressing the button, and injection amount deviation caused by poor force control is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to a push-type automatic injection pen. Background Art

[0002] In the medical field, the use of automatic injection devices is becoming increasingly popular, especially in cases where self-administered drug therapy is required, such as insulin injection for diabetic patients, and automatic injection of epinephrine for first aid in allergic reactions. The core value of such devices lies in simplifying the injection process, improving the safety and convenience of medication, and reducing problems such as pain or inaccurate dosing caused by improper operation by patients.

[0003] Traditional automatic syringes mostly rely on the combination of pre-filled medicine cartridges and mechanical or electronic drive mechanisms to achieve automatic injection of the medicine. Among them, as a common design, the push-type automatic injection pen allows users to continuously press a button to push the medicine in the medicine cartridge through a needle into the patient's body. However, early push-type injection pens often had problems such as uncontrollable injection speed and large influence of human factors on dose accuracy, which limited their wide application in specific patient groups, especially for users with poor strength control or fear of the injection process.

[0004] The present utility model is made based on the above situation. Summary of the Utility Model

[0005] The utility model overcomes the deficiencies of the prior art and provides a push-type automatic injection pen that can adjust the compression degree of a spring through a knob to perform quantitative injection.

[0006] The present utility model is realized through the following technical solutions:

[0007] A push-type automatic injection pen includes a pen body tube and a cartridge holder connected to the pen body tube for placing a medicine cartridge. A screw rod, a positioner, and a clutch mechanism for driving the screw rod to rotate are provided inside the pen body tube. The positioner is fixedly connected to the pen body tube, and the screw rod is threadedly connected to the positioner. A transmission structure for rotating the clutch mechanism is also provided inside the pen body tube. The clutch mechanism has an engaged state and a disengaged state. A spring for rotating the transmission structure is also provided inside the pen body tube. A knob for adjusting the compression amount of the spring is sleeved outside the spring. A damping structure for restricting the reverse reset of the knob when the spring is in a compressed state is provided between the pen body tube and the knob. A button that can release the spring and switch the clutch mechanism to the engaged state is slidably connected to the knob. The clutch mechanism is provided with a first spring for switching it from the engaged state to the disengaged state.

[0008] A push-type automatic injection pen as described above, wherein the clutch mechanism includes a clutch and a transmission sleeve. The screw rod is inserted into the clutch, and a transmission rod for enabling the screw rod to rotate following the clutch is provided between the screw rod and the clutch. A first clamping block is provided on the outer wall at the front end of the clutch, and a first clamping groove capable of being clamped with the first clamping block so that the clutch can rotate following the transmission sleeve is provided at the front end of the transmission sleeve. The first spring is provided between the locator and the transmission sleeve and is used to push the transmission sleeve to disengage the first clamping block from the first clamping groove.

[0009] A push-type automatic injection pen as described above, wherein the transmission structure includes a connecting column connected to the rear end of the transmission sleeve and passing through the knob. A fixed gear sleeve is sleeved on the connecting column, and a first limiting structure for restricting the rotation of the fixed gear sleeve is provided between the fixed gear sleeve and the pen body tube. The spring is sleeved on the connecting column and is located inside the fixed gear sleeve. The inner end of the spring is connected to the connecting column, and the outer end of the spring is connected to the fixed gear sleeve.

[0010] A push-type automatic injection pen as described above, wherein a guide sleeve is fixedly connected inside the pen body tube. The first limiting structure includes a second clamping groove provided on the outer wall of the fixed gear sleeve and a second clamping block provided on the inner wall of the guide sleeve and clamped with the second clamping groove.

[0011] A push-type automatic injection pen as described above, wherein a bayonet is provided on the knob, a clamping block for cooperating with the bayonet so that the knob drives the connecting column to rotate is provided on the connecting column, and a ejector rod capable of ejecting the clamping block out of the bayonet when the button is pressed so as to release the spring is provided on the button.

[0012] A push-type automatic injection pen as described above, wherein the damping structure includes a fixed triangular tooth provided at the rear end of the guide sleeve and a sliding frame provided between the button and the knob and capable of rotating following the knob. A movable triangular tooth is provided on the sliding frame, and a second spring for pushing the sliding frame towards the knob so that the movable triangular tooth meshes with the fixed triangular tooth is provided between the sliding frame and the button.

[0013] A push-type automatic injection pen as described above, wherein a dose knob is threadedly connected inside the guide sleeve. The dose knob is slidably connected to the transmission sleeve. A scale is provided on the outer wall of the dose knob, and an observation indicating port for observing the scale is provided on the guide sleeve and the pen body tube.

[0014] A push-type automatic injection pen as described above, wherein a fixed anti-backlash tooth is connected to the rear end of the locator. A movable anti-backlash tooth capable of sliding along it is sleeved on the screw rod. A third spring for pushing the movable anti-backlash tooth towards the fixed anti-backlash tooth so that the two mesh to restrict the reverse rotation of the transmission rod is provided between the movable anti-backlash tooth and the locator. The inner wall of the movable anti-backlash tooth is clamped on the transmission rod so that the two rotate together.

[0015] A push-type automatic injection pen as described above, a hollow stud is connected to the rear end of the clutch, a locking ring is threadedly connected to the hollow stud, a guiding groove is provided on the outer wall of the locking ring, and a limiting rib that can be inserted into the guiding groove to limit the rotation of the locking ring relative to the transmission sleeve is provided on the inner wall of the transmission sleeve.

[0016] A push-type automatic injection pen as described above, a piston is connected to the front end of the screw rod.

[0017] Compared with the prior art, the present utility model has the following advantages:

[0018] In this case, a spring for rotating the transmission structure is further provided in the pen body tube, a knob for adjusting the compression amount of the spring is sleeved outside the spring, the injection amount is adjusted by adjusting the compression degree of the spring through the knob, and the spring is released by pressing the button and the clutch mechanism is switched to the engaged state, so as to realize the automatic pushing of the medicine cartridge by the screw rod for injection, without the need to continuously press the button to control the injection amount, and avoid the injection amount deviation caused by poor force control. Description of the Drawings

[0019] The following further describes the specific embodiments of the present utility model in conjunction with the drawings, where:

[0020] Figure 1 is an exploded view of the present utility model;

[0021] Figure 2 is a cross-sectional view of the present utility model;

[0022] Figure 3 is a cross-sectional view after the present utility model is disassembled;

[0023] Figure 4 is a structural schematic diagram of the sliding frame in the present utility model;

[0024] Figure 5 is a structural schematic diagram of the guide sleeve in the present utility model. Detailed Description of the Embodiments

[0025] The following further describes the present utility model in conjunction with the drawings:

[0026] As Figures 1 to 5A push-type automatic injection pen as shown, including a push-type automatic injection pen, which is characterized in that: it includes a pen body tube 1 and a cartridge holder 2 connected to the pen body tube 1 for placing a medicine cartridge. A screw rod 3, a locator 4 for extending into the cartridge holder 2 to push out the medicine in the cartridge, and a clutch mechanism for driving the screw rod 3 to rotate are provided in the pen body tube 1. The locator 4 is fixedly connected to the pen body tube 1. The screw rod 3 is threadedly connected to the locator 4. A transmission structure for rotating the clutch mechanism is also provided in the pen body tube 1. The clutch mechanism has an engaged state and a disengaged state. A spring 5 for rotating the transmission structure is also provided in the pen body tube 1. A knob 6 for adjusting the compression amount of the spring 5 is sleeved outside the spring 5. A damping structure for restricting the reverse reset of the knob 6 when the spring 5 is in a compressed state is provided between the pen body tube 1 and the knob 6. A button 7 that can release the spring 5 and switch the clutch mechanism to the engaged state is slidably connected to the knob 6. The clutch mechanism is provided with a first spring 8 for switching it from the engaged state to the disengaged state. The cartridge holder 2 is connected to the front end of the pen body tube 1 by a snap structure or other connection methods such as threaded connection. The cartridge holder 2 is a conventional cartridge holder for an injection pen and will not be elaborated here in detail. An injection needle 20 is threadedly connected to the front end of the cartridge holder 2. A pen cap 10 that can cover the cartridge holder 2 and the injection needle 20 is snap-connected to the front end of the pen body tube 1.

[0027] A spring 5 for rotating the transmission structure is also provided in the pen body tube 1. A knob 6 for adjusting the compression amount of the spring is sleeved outside the spring 5. The compression degree of the spring 5 is adjusted by the knob 6 to adjust the injection amount. By pressing the button 7, the spring 5 is released and the clutch mechanism is switched to the engaged state, so as to realize the automatic pushing of the medicine cartridge by the screw rod 3 for injection, without continuously pressing the button 7 to control the injection amount, and avoiding injection amount deviation due to poor force control.

[0028] In some embodiments, the clutch mechanism includes a clutch 91 and a transmission sleeve 92. The screw rod 3 is inserted into the clutch 91. A transmission rod 93 for making the screw rod 3 rotate following the clutch 91 is provided between the screw rod 3 and the clutch 91. A first block 911 is provided on the outer wall of the front end of the clutch 91. A first slot 921 for engaging with the first block 911 so that the clutch 91 can rotate following the transmission sleeve 92 is provided at the front end of the transmission sleeve 92. The first spring 8 is provided between the locator 4 and the transmission sleeve 92 and is used to push the transmission sleeve 92 to disengage the first block 911 from the first slot 921. Among them, after the transmission rod 93 is inserted into the clutch 91, the outer wall of the transmission rod 93 and the inner wall of the clutch 91 are connected by a snap structure such as a block and a slot, so that the transmission rod 93 and the clutch 91 rotate synchronously.

[0029] The transmission structure includes a connecting column 922 connected to the rear end of the transmission sleeve 92 and passing through the knob 6. A fixed gear sleeve 923 is sleeved on the connecting column 922. A first limiting structure for restricting the rotation of the fixed gear sleeve 923 is provided between the fixed gear sleeve 923 and the pen body tube 1. The clockwork spring 5 is sleeved on the connecting column 922 and is located inside the fixed gear sleeve 923. The inner end of the clockwork spring 5 is connected to the connecting column 922, and the outer end of the clockwork spring 5 is connected to the fixed gear sleeve 923. A guide sleeve 11 is fixedly connected inside the pen body tube 1. The first limiting structure includes a second card slot 111 provided on the outer wall of the fixed gear sleeve 923 and a second card block 112 provided on the inner wall of the guide sleeve 11 and engaged with the second card slot 111. A bayonet 61 is provided on the knob 6. A clamping block 62 is provided on the connecting column 922 and is engaged with the bayonet 61 so that the knob 6 drives the connecting column 922 to rotate. A push rod 71 is provided on the button 7 and can eject the clamping block 62 out of the bayonet 61 when the button 7 is pressed, so that the clockwork spring 5 is released. Among them, the push rod 71 and the button 7 are integrally formed, and the end of the push rod 71 can be restricted from separating from the knob 6 by a limiting block. The bayonet 61 is provided with first teeth, and the clamping block 62 is provided with second teeth engaged with the first teeth. When the clamping block 62 disengages from the bayonet 61, the clutch mechanism switches to the engaged state, and the clockwork spring 5 returns from the compressed state to drive the transmission sleeve 92 to rotate. The transmission sleeve 92 drives the clutch 91 to rotate, the clutch 91 drives the transmission rod 93 to rotate, and the transmission rod 93 drives the screw rod 3 to rotate. As a result, the screw rod 3 moves forward due to the restriction of the locator 4, so as to extrude the medicine of the medicine pen refill. The clockwork spring 5 is connected to the connecting column 922 and the fixed gear sleeve 923 by means of threaded fasteners or other connection methods such as clamping.

[0030] In one embodiment, a piston 31 is connected to the front end of the screw rod 3 to increase the contact area and prevent the medicine pen refill from being damaged due to excessive stress concentration. Among them, the piston 31 can be connected to the screw rod 3 by means of threaded connection or other connection methods. A clamping wall is provided on the side of the screw rod 3, and a block structure engaged with the clamping wall is provided on the inner wall of the transmission rod 93 so that the screw rod 3 follows the transmission rod 93 to rotate.

[0031] In some embodiments, the damping structure includes a fixed triangular tooth 113 provided at the rear end of the guide sleeve 11 and a sliding frame 63 provided between the button 7 and the knob 6 and capable of rotating with the knob 6. An active triangular tooth 631 is provided on the sliding frame 63, and a second spring 64 is provided between the sliding frame 63 and the button 7 to push the sliding frame 63 towards the knob 6 so that the active triangular tooth 631 meshes with the fixed triangular tooth 113. Among them, a first gentle slope 1131 and a first steep slope 1132 are provided on each of the fixed triangular teeth 113, and a second gentle slope 6311 matching the first gentle slope 1131 and a second steep slope 6312 matching the first steep slope 1132 are provided on each of the active triangular teeth 631. When rotating the knob 6 to increase the injection volume, the first gentle slope 1131 and the second gentle slope 6311 cooperate, and the slope is small, so a relatively small force can be used to increase the injection volume. And each time the active triangular tooth 631 moves through a fixed triangular tooth 113 is an increase amount, increasing the compression amount of the mainspring 5. Under the action of the second spring 64, the second steep slope 6312 will be attached to the first steep slope 1132, and a clicking sound will be emitted during adjustment. At the same time, the first steep slope 1132 and the second steep slope 6312 cooperate, and the slope is large, and a relatively large force is required to reverse-rotate the knob 6, so as to limit the reverse rotation of the button 6, that is, it can also limit the reverse rotation of the transmission sleeve 92 to release the mainspring 5. When the adjustment amount is accidentally adjusted to be greater than the desired value, the knob 6 can be reverse-rotated with a relatively large force, thereby reducing the compression amount of the mainspring 5. The first steep slope 1132 will push the second steep slope 6312 so that the active triangular tooth 631 disengages from the fixed triangular tooth 113, and each time the active triangular tooth 631 moves through a fixed triangular tooth 113 is a decrease amount. Under the action of the second spring 64, the second steep slope 6312 will be attached to the first steep slope 1132, and a clicking sound will be emitted during adjustment.

[0032] In some embodiments, a dose knob 12 is threadedly connected inside the guide sleeve 11. The dose knob 12 is slidably connected to the transmission sleeve 92 through a slide rail structure. A scale is provided on the outer wall of the dose knob 12, and an observation indication port 13 for observing the scale is provided on the guide sleeve 11 and the pen body tube 1. When rotating the knob 6 to adjust the injection volume, the dose knob 12 rotates with the transmission sleeve 92 and displays the injection value reached by the release of the mainspring 5 at the observation indication port 13.

[0033] The rear end of the locator 4 is connected with a fixed anti-reverse tooth 41. An active anti-reverse tooth 42 capable of sliding along the screw rod 3 is sleeved on the screw rod 3. A third spring 43 is arranged between the active anti-reverse tooth 42 and the locator 4, which can push the active anti-reverse tooth 42 towards the fixed anti-reverse tooth 41 to make the two engage, thereby restricting the reverse rotation of the transmission rod 93. The inner wall of the active anti-reverse tooth 42 is clamped on the transmission rod 93, so that the two rotate together. The reverse rotation of the screw rod 3 is prevented from retreating by the cooperation of the active anti-reverse tooth 42 and the fixed anti-reverse tooth 41, so as to ensure an accurate injection volume.

[0034] The rear end of the clutch 91 is connected with a hollow stud 912. A locking ring 913 is threadedly connected to the hollow stud 912. A guiding groove 914 is arranged on the outer wall of the locking ring 913. A limiting rib 915 capable of inserting into the guiding groove 914 is arranged on the inner wall of the transmission sleeve 92 to restrict the relative rotation of the locking ring 913 with respect to the transmission sleeve 92. When the moving amount of the screw rod 3 reaches the maximum set value, the locking ring 913 locks the clutch 91 and the transmission sleeve 92, thereby restricting the turning of the knob 6, thus indicating that the medicine in the medicine cartridge is empty.

Claims

1. A push-type automatic injection pen, characterized in that: The invention comprises a pen body tube (1) and a refill frame (2) connected to the pen body tube (1) for placing a medicine refill, wherein the pen body tube (1) is provided with a spiral rod (3) for extending into the refill frame (2) to push out the medicine in the refill, a positioner (4), and a clutch mechanism for driving the spiral rod (3) to rotate, wherein the positioner (4) is fixedly connected to the pen body tube (1), the spiral rod (3) is threadedly connected to the positioner (4), and the pen body tube (1) is further provided with a transmission structure capable of rotating the clutch mechanism, wherein the clutch mechanism has an engaged state and an engaged state. In the disengaged state, a spring (5) for rotating the transmission structure is further provided in the pen body tube (1), a knob (6) capable of adjusting the compression amount of the spring (5) is sleeved on the outer side of the spring (5), a damping structure capable of limiting the knob (6) from reversing and resetting when the spring (5) is in the compressed state is provided between the pen body tube (1) and the knob (6), a button (7) capable of releasing the spring (5) and switching the clutch mechanism to the engaged state is slidably connected to the knob (6), and the clutch mechanism is provided with a first spring (8) for switching the engaged state to the disengaged state.

2. A push-type automatic injection pen according to claim 1, characterized in that: The clutch mechanism comprises a clutch (91) and a transmission sleeve (92); the screw rod (3) is inserted into the clutch (91); a transmission rod (93) is provided between the screw rod (3) and the clutch (91) so that the screw rod (3) rotates following the clutch (91); a first clamping block (911) is provided on the outer wall of the front end of the clutch (91); the front end of the transmission sleeve (92) is provided with a first clamping groove (921) which can be clamped with the first clamping block (911) so that the clutch (91) can rotate following the transmission sleeve (92); the first spring (8) is provided between the positioner (4) and the transmission sleeve (92) and is used to push the transmission sleeve (92) so that the first clamping block (911) is separated from the first clamping groove (921).

3. A push-type automatic injection pen according to claim 2, characterized in that: The transmission structure comprises a connecting column (922) connected to the rear end of the transmission sleeve (92) and passing through the knob (6); a fixed tooth sleeve (923) is sleeved on the connecting column (922); a first limiting structure for limiting the rotation of the fixed tooth sleeve (923) is provided between the fixed tooth sleeve (923) and the pen body tube (1); the mainspring (5) is sleeved on the connecting column (922) and located inside the fixed tooth sleeve (923); the inner end of the mainspring (5) is connected to the connecting column (922), and the outer end of the mainspring (5) is connected to the fixed tooth sleeve (923).

4. A push-type automatic injection pen according to claim 3, characterized in that: A guide sleeve (11) is fixedly connected inside the pen body tube (1), and the first limiting structure comprises a second clamping groove (111) arranged on the outer wall of the fixed tooth sleeve (923) and a second clamping block (112) arranged on the inner wall of the guide sleeve (11) and clamped with the second clamping groove (111).

5. The push-type automatic injection pen according to claim 4, characterized in that: The knob (6) is provided with a bayonet (61), the connecting column (922) is provided with a clamping block (62) which cooperates with the bayonet (61) so that the knob (6) drives the connecting column (922) to rotate, and the button (7) is provided with a push rod (71) which can push the clamping block (62) out of the bayonet (61) when the button (7) is pressed, thereby releasing the mainspring (5).

6. The push-type automatic injection pen according to claim 5, characterized in that: The damping structure comprises a fixed triangular tooth (113) arranged on the rear end of the guide sleeve (11) and a sliding frame (63) arranged between the button (7) and the knob (6) and capable of rotating with the knob (6); a movable triangular tooth (631) is arranged on the sliding frame (63); and a second spring (64) is arranged between the sliding frame (63) and the button (7) to push the sliding frame (63) toward the knob (6) so that the movable triangular tooth (631) engages with the fixed triangular tooth (113).

7. The push-type automatic injection pen according to claim 4, characterized in that: The guide sleeve (11) is internally threadedly connected with a dosage knob (12), the dosage knob (12) is slidably connected to the transmission sleeve (92), a scale is provided on the outer wall of the dosage knob (12), and an observation indication port (13) for observing the scale is provided on the guide sleeve (11) and the pen body tube (1).

8. The push-type automatic injection pen according to claim 2, characterized in that: The rear end of the positioner (4) is connected to a fixed back-stopping tooth (41), and the spiral rod (3) is sleeved with a movable back-stopping tooth (42) that can slide along the spiral rod (3). A third spring (43) is provided between the movable back-stopping tooth (42) and the positioner (4) and can push the movable back-stopping tooth (42) toward the fixed back-stopping tooth (41) so that the two are engaged and thus limit the reverse rotation of the transmission rod (93). The inner wall of the movable back-stopping tooth (42) is clamped on the transmission rod (93) so that the two rotate together.

9. The push-type automatic injection pen according to claim 2, characterized in that: The rear end of the clutch (91) is connected to a hollow stud (912), a locking ring (913) is threadedly connected to the hollow stud (912), a guide groove (914) is provided on the outer wall of the locking ring (913), and a limiting edge (915) that can be inserted into the guide groove (914) to limit the rotation of the locking ring (913) relative to the transmission sleeve (92) is provided on the inner wall of the transmission sleeve (92).

10. The push-type automatic injection pen according to claim 1, characterized in that: The front end of the spiral rod (3) is connected to a piston (31).

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