A torsion spring anti-collision device for an injection pen

Abstract

The present application provides a torsional spring anti-collision device of an injection pen, comprising a shell, a proximal end of the shell, a distal end of the shell, one end of a torsional spring connected to a dose dial holder, the other end connected to a spring fixing structure, the torsional spring mounting slot of the spring fixing structure shortened to the side wall of the torsional spring, when the torsional spring hook of the torsional spring is inserted into the torsional spring mounting slot, there is no blocking force, at the same time, the side wall of the torsional spring mounting slot away from the torsional spring is gradually increased along the walking track of the torsional spring hook, which reduces the installation difficulty of the torsional spring, reduces the cost, avoids the torsional spring from being deformed when the torsional spring hook is radially extruded during reinstallation, and avoids the phenomenon that the injection button cannot rebound, thereby improving the injection accuracy, improving the reliability of the structure, and reducing the failure rate.

Description

Technical Field

[0001] This invention relates to the field of adjustable dosage injection device technology, and more specifically, to a torsion spring anti-collision device for an injection pen. Background Technology

[0002] The adjustable dosing injection device comprises a dosing adjustment and injection mechanism and a cartridge retaining mechanism. When adjusting the dosing, the user rotates a dosing adjustment element on the dosing pouring mechanism; the force applied by the user is stored in a torsion spring for subsequent dispensing. To dispensing the adjusted dose, the user presses a dispensing button on the proximal end of the syringe; the torsional force accumulated in the torsion spring is then delivered to the drive element to propel the liquid out of the injection device.

[0003] Chinese invention patent CN118490935A discloses a torsion spring anti-collision device for an injection pen, comprising a housing, the front end of which is a proximal end and the rear end of which is a distal end. The distal end of the housing is provided with a fixed end cap, which is sleeved with a screw bracket 141. One end of the screw bracket 141 passes through the fixed end cap and is connected to a dose setting element. A dose display bracket is sleeved on the outer periphery of the screw bracket 141, and the dose display bracket and the fixed end cap are engaged by ratchet teeth with beveled ends, so that the screw bracket 141 can only move back and forth along the axial direction relative to the dose setting element and the dose display bracket. The dose setting element is connected to the distal end of the housing, so that the dose setting element can only rotate relative to the housing. A torsion spring is provided between the screw bracket 141 and the dose display bracket. One end of the torsion spring is connected to the proximal end of the dose display bracket near the housing, and the other end is connected to the fixed end cap.

[0004] However, the existing torsion spring 70 is difficult to install with the fixed end cap. It cannot be twisted in directly, and the torsion spring 70 will burst during the pre-tightening process, causing the injection button 80 to fail to return to its normal position. Therefore, how to solve the above problems has become the problem that needs to be solved at present. Summary of the Invention

[0005] In view of this, the present invention proposes a torsion spring anti-collision device for an injection pen, including a housing 10, the front end of which is the near end and the rear end of which is the far end. One end of the torsion spring 70 is connected to the dosage scale support 60, and the other end is connected to the spring fixing structure 20. The torsion spring mounting groove 23 of the spring fixing structure 20 is shortened near the side wall of the torsion spring 70 until there is no obstruction when the torsion spring hook 71 of the torsion spring 70 is inserted into the torsion spring mounting groove 23. At the same time, the side wall of the torsion spring mounting groove 23 away from the torsion spring 70 is gradually enlarged along the travel trajectory of the torsion spring hook 71 of the torsion spring 70, reducing the installation difficulty of the torsion spring 70, reducing costs, and preventing the torsion spring 70 from generating additional radial force during the power storage process when the torsion spring hook 71 is installed, which could deform the torsion spring 70 and cause it to burst. At the same time, it avoids the phenomenon that the injection button 80 cannot rebound, and avoids failure caused by the deformation of the torsion spring 70, thereby improving injection accuracy, improving structural reliability, and reducing the failure rate.

[0006] A torsion spring anti-collision device for an injection pen includes a housing 10, with a front end as the proximal end and a rear end as the distal end. The distal end of the housing 10 is provided with a spring fixing structure 20. A screw sleeve 30 is fitted inside the housing 10, passing through an adjustment knob 50 and engaging with an injection button 80. A torsion spring 70 and a dosage scale support 60 are fitted around the outer periphery of the screw sleeve 30. One end of the torsion spring 70 is connected to the dosage scale support 60, and the other end is connected to the spring fixing structure 20. The spring fixing structure 20 is provided with a torsion spring mounting groove 23. One end of the torsion spring 70 is provided with a torsion spring hook 71. The torsion spring mounting groove 23 of the spring fixing structure 20 is shortened near the side wall of the torsion spring 70 until there is no obstruction when the torsion spring hook 71 of the torsion spring 70 is inserted into the torsion spring mounting groove 23. The torsion spring mounting groove 23 is then moved away from the torsion spring mounting structure 20. The sidewall of the torsion spring 70 gradually increases along the travel trajectory of the torsion hook 71. Since the size and shape of the torsion spring mounting groove 23 are basically consistent with the shape of the torsion spring 70 when it is installed on the injection pen and subjected to force, especially when the torsion hook 71 of the torsion spring 70 is installed on the spring fixing structure 20, the direction in which the torsion hook 71 enters the torsion spring mounting groove 23 is completely consistent. This prevents the torsion spring 70 from deforming due to the force on the torsion hook 71, reduces the installation difficulty of the torsion spring 70, reduces costs, and avoids the additional radial force generated during the energy storage process when the torsion spring 70 is subjected to radial compression after the torsion hook 71 is installed, which could cause the torsion spring 70 to deform and burst. At the same time, it avoids the phenomenon that the injection button 80 cannot rebound, avoids failure caused by the deformation of the torsion spring 70, thereby improving injection accuracy, improving structural reliability, and reducing the failure rate.

[0007] Furthermore, the torsion spring mounting groove 23 gradually increases in size from the insertion point of the torsion spring hook 71.

[0008] Furthermore, the outer wall of the torsion spring mounting groove 23 gradually increases from the insertion point of the torsion spring hook 71.

[0009] Furthermore, the torsion spring mounting groove 23 is enlarged by opening the groove in an involute pattern.

[0010] Furthermore, the bottom of the torsion spring mounting groove 23 is provided with a limiting step 24, and the connection between the torsion spring 70 and the torsion spring 70 is provided with a most curved arc surface 72. When the torsion spring 70 and the spring fixing structure 20 are installed, the most curved arc surface 72 is in contact with the free end of the limiting step 24.

[0011] Furthermore, the travel trajectory of the torsion hook 71 of the torsion spring 70 always travels along the torsion spring mounting groove 23 of the spring fixing structure 20, close to the side wall of the torsion spring 70.

[0012] Furthermore, the free end of the inner wall of the torsion spring mounting groove 23 near the side wall of the torsion spring 70 is provided with a guide surface 25 for guiding the torsion spring hook 71 of the torsion spring 70 into the torsion spring mounting groove 23.

[0013] Furthermore, the guide surface 25 is misaligned with the torsion spring mounting groove 23, so that the torsion spring hook 71 for the torsion spring 70 does not interfere with the guide surface 25.

[0014] In some embodiments, the outer periphery of the spring fixing structure 20 is provided with a plurality of first hooks 21, and the corresponding position of the distal end of the housing 10 is provided with a first slot 11 that is engaged with it, and the first hooks 21 and the first slots 11 are matched and engaged.

[0015] Furthermore, the outer periphery of the spring fixing structure 20 is provided with a first protrusion 22, and the corresponding position of the far end of the housing 10 is provided with a first notch 12. When the housing 10 and the spring fixing structure 20 are matched and installed, the first protrusion 22 is just engaged with the first notch 12, thereby enhancing the connection between the spring fixing structure 20 and the housing 10.

[0016] In some embodiments, a screw injection mechanism 14 is provided at the proximal end of the housing 10. The screw sleeve 30 passes through the adjustment knob 50 and is sleeved with the injection button 80. The adjustment knob 50 is connected to the distal end of the housing 10 and can only rotate relative to the housing 10. A torsion spring 70, a dosage scale support 60, and a dosage display element 90 are sleeved on the outer periphery of the screw sleeve 30. The dosage display element 90 is screwed to the housing 10. When injection is performed, the screw sleeve 30 disengages from the injection button 80 and moves towards the proximal end. After the screw injection mechanism 14 is engaged, injection is performed. The torsion spring 70 releases energy, and the screw sleeve 30, the dosage scale support 60, the dosage display element 90, and the adjustment knob 50 rotate in opposite directions. The dosage display element 90 moves towards the distal end along the thread of the housing 10. When adjusting the dosage, the adjustment knob 50 is rotated in the forward direction, which drives the screw sleeve 30, the dosage scale support 60, and the dosage display element 90 to rotate synchronously, and stores energy in the torsion spring 70. The dosage display element 90 moves towards the proximal end along the thread of the housing 10.

[0017] In some embodiments, the outer periphery of the dose scale support 60 is provided with a plurality of parallel first ribs 61 arranged at intervals along the axial direction, which are used to match and connect with the first groove on the inner wall of the dose display element 90. The dose display element 90 is rotatably connected to the inner wall of the housing 10 by a spiral pattern, so that the dose display element 90 can only move back and forth along the axial direction relative to the dose scale support 60.

[0018] Furthermore, the housing 10 is provided with a dose display window, which works in conjunction with the dose display element 90 to display the required injection dose and the injection volume during the injection process.

[0019] In some embodiments, the inner wall of the dose scale support 60 is provided with a second groove 63 near the proximal end of the housing 10, and the screw sleeve 30 is provided with a second rib 31 at the corresponding position. The second groove 63 and the second rib 31 are matched and connected, so that the screw sleeve 30 can only move back and forth along the axial direction relative to the dose scale support 60.

[0020] In some embodiments, the screw sleeve 30 is provided with a third rib 32 at the distal end near the housing 10, and the inner wall of the adjusting knob 50 is provided with a third groove at a corresponding position. The third groove is matched and connected with the third rib 32, so that the screw sleeve 30 can only move back and forth along the axial direction relative to the adjusting knob 50.

[0021] The beneficial effects of this invention: This invention proposes a torsion spring anti-collision device for an injection pen, including a housing 10, the front end of which is the proximal end and the rear end of which is the distal end. One end of the torsion spring 70 is connected to the dosage scale support 60, and the other end is connected to the spring fixing structure 20. The torsion spring mounting groove 23 of the spring fixing structure 20 is shortened near the side wall of the torsion spring 70 until there is no obstruction when the torsion spring hook 71 of the torsion spring 70 is inserted into the torsion spring mounting groove 23. At the same time, the torsion spring mounting groove 23 is gradually enlarged away from the side wall of the torsion spring 70 along the travel trajectory of the torsion spring hook 71 of the torsion spring 70. Due to the size and shape of the torsion spring mounting groove 23 and the torsion spring 70 being installed on the injection pen, the device provides a more comprehensive anti-collision device. The shape of the pen under stress is basically consistent, especially when the torsion spring hook 71 of the torsion spring 70 is installed on the spring fixing structure 20. The direction of the torsion spring hook 71 entering the torsion spring mounting groove 23 is completely consistent, so that the torsion spring 70 will not deform due to the force of the torsion spring hook 71, reducing the installation difficulty of the torsion spring 70, reducing costs, and avoiding the additional radial force generated during the storage process when the torsion spring 70 is subjected to radial compression after the torsion spring hook 71 is installed, which would cause the torsion spring 70 to deform and explode. At the same time, it avoids the phenomenon that the injection button 80 cannot rebound, avoids failure caused by the deformation of the torsion spring 70, thereby improving injection accuracy, improving structural reliability, and reducing failure rate. Attached Figure Description

[0022] Figure 1 This is a cross-sectional view of the injection pen of the present invention.

[0023] Figure 2 This is an exploded view of the overall torsion spring anti-collision device of the injection pen of the present invention.

[0024] Figure 3 This is a structural diagram of the connecting part of the housing of the torsion spring anti-collision device for the injection pen of the present invention.

[0025] Figure 4 This is a structural diagram of the fixed end cap of the torsion spring anti-collision device for the injection pen of the present invention.

[0026] Figure 5 This is a structural diagram of the screw sleeve of the torsion spring anti-collision device for the injection pen of the present invention.

[0027] Figure 6 This is a structural diagram showing the connection between the housing and the spring fixing structure of the torsion spring anti-collision device for the injection pen of the present invention.

[0028] Explanation of main component symbols

[0029] Housing 10; First slot 11; First notch 12; Screw injection mechanism 14; Spring fixing structure 20; First hook 21; First protrusion 22; Torsion spring mounting groove 23; Limiting step 24; Guide surface 25; Screw sleeve 30; Second rib 31; Third rib 32; Adjustment knob 50; Dosage scale support 60; First rib 61; Second groove 63; Torsion spring 70; Torsion spring hook 71; Most curved arc surface 72; Injection button 80; Dosage display element 90.

[0030] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation Example 1

[0031] like Figure 1-4 and Figure 6 As shown, a torsion spring anti-collision device for an injection pen includes a housing 10, with a front end as the proximal end and a rear end as the distal end. The distal end of the housing 10 is provided with a spring fixing structure 20. A screw sleeve 30 is fitted inside the housing 10, passing through an adjustment knob 50 and engaging with an injection button 80. A torsion spring 70 and a dosage scale support 60 are fitted around the outer periphery of the screw sleeve 30. One end of the torsion spring 70 is connected to the dosage scale support 60, and the other end is connected to the spring fixing structure 20. The spring fixing structure 20 is provided with a torsion spring mounting groove 23, and one end of the torsion spring 70 is provided with a torsion spring hook 71. The torsion spring mounting groove 23 of the spring fixing structure 20 is shortened near the side wall of the torsion spring 70 until there is no obstruction when the torsion spring hook 71 of the torsion spring 70 is inserted into the torsion spring mounting groove 23. The torsion spring mounting groove 23 is then shortened further away from the side wall of the torsion spring 70. The distance from the side wall of the torsion spring 70 gradually increases along the travel trajectory of the torsion hook 71 of the torsion spring 70. Since the size and shape of the torsion spring mounting groove 23 are basically consistent with the shape of the torsion spring 70 when it is installed on the injection pen and subjected to force, especially when the torsion hook 71 of the torsion spring 70 is installed on the spring fixing structure 20, the direction in which the torsion hook 71 enters the torsion spring mounting groove 23 is completely consistent. This prevents the torsion spring 70 from deforming due to the force on the torsion hook 71, reduces the installation difficulty of the torsion spring 70, reduces costs, and avoids the additional radial force generated during the energy storage process when the torsion spring 70 is subjected to radial compression after the torsion hook 71 is installed, which could cause the torsion spring 70 to deform and burst. At the same time, it avoids the phenomenon that the injection button 80 cannot rebound, avoids failure caused by the deformation of the torsion spring 70, thereby improving injection accuracy, improving structural reliability, and reducing the failure rate.

[0032] The outer wall of the torsion spring mounting groove 23 gradually increases from the insertion of the torsion spring hook 71. The torsion spring mounting groove 23 increases in an involute manner. The bottom of the torsion spring mounting groove 23 is provided with a limiting step 24. The connection between the torsion spring 70 and the torsion spring 70 is provided with a most curved arc surface 72. When the torsion spring 70 and the spring fixing structure 20 are installed, the most curved arc surface 72 is in contact with the free end of the limiting step 24. The travel trajectory of the torsion spring hook 71 of the torsion spring 70 always travels along the side wall of the torsion spring mounting groove 23 of the spring fixing structure 20, close to the side wall of the torsion spring 70. The free end of the inner wall of the torsion spring mounting groove 23 close to the side wall of the torsion spring 70 is provided with a guide surface 25 towards the torsion spring mounting groove 23. This guide surface 25 is used to guide the torsion spring hook 71 of the torsion spring 70 into the torsion spring mounting groove 23. The guide surface 25 is offset from the torsion spring mounting groove 23 so that the torsion spring hook 71 of the torsion spring 70 does not interfere with the guide surface 25.

[0033] The outer periphery of the spring fixing structure 20 is provided with a plurality of first hooks 21, and the corresponding position of the far end of the housing 10 is provided with a first slot 11 that is engaged with it. The first hooks 21 and the first slots 11 are matched and engaged.

[0034] The proximal end of the housing 10 is provided with a screw injection mechanism 14. The screw sleeve 30 passes through the adjustment knob 50 and is sleeved with the injection button 80. The adjustment knob 50 is connected to the distal end of the housing 10 and can only rotate relative to the housing 10. A torsion spring 70, a dosage scale support 60, and a dosage display element 90 are sleeved on the outer periphery of the screw sleeve 30. The dosage display element 90 is screwed to the housing 10. When injection is performed, the screw sleeve 30 disengages from the injection button 80 and moves towards the proximal end until it is in contact with the screw. After the rod injection mechanism 14 is engaged, injection is performed. The torsion spring 70 releases energy, and the screw sleeve 30, the dosage scale support 60, the dosage display element 90, and the adjustment knob 50 rotate in opposite directions. The dosage display element 90 moves towards the distal end along the thread of the housing 10. When adjusting the dosage, the adjustment knob 50 is rotated in the forward direction, which drives the screw sleeve 30, the dosage scale support 60, and the dosage display element 90 to rotate synchronously, and stores energy in the torsion spring 70. The dosage display element 90 moves towards the proximal end along the thread of the housing 10.

[0035] Figure 4As shown, the outer periphery of the spring fixing structure 20 is also provided with a first protrusion 22, and the corresponding position of the distal end of the housing 10 is provided with a first notch 12. When the housing 10 and the spring fixing structure 20 are matched and installed, the first protrusion 22 is just engaged with the first notch 12, thereby enhancing the connection between the spring fixing structure 20 and the housing 10. The outer periphery of the dose scale support 60 is provided with multiple parallel first ribs 61 arranged at intervals along the axial direction, which are used to match and connect with the first groove on the inner wall of the dose display element 90. The dose display element 90 is connected to the inner wall of the housing 10 by a spiral groove, so that the dose display element 90 can only move back and forth along the axial direction relative to the dose scale support 60. The housing 10 is provided with a dose display window, which cooperates with the dose display element 90 to display the required injection dose and the injection volume during the injection process.

[0036] like Figure 2 and Figure 5 As shown, the inner wall of the dose scale support 60 near the proximal end of the housing 10 is provided with a second groove 63, and the corresponding position of the screw sleeve 30 is provided with a second rib 31. The second groove 63 and the second rib 31 are matched and connected, so that the screw sleeve 30 can only move back and forth along the axial direction relative to the dose scale support 60. The distal end of the screw sleeve 30 near the housing 10 is provided with a third rib 32, and the corresponding position of the inner wall of the adjustment knob 50 is provided with a third groove. The third groove and the third rib 32 are matched and connected, so that the screw sleeve 30 can only move back and forth along the axial direction relative to the adjustment knob 50.

[0037] The beneficial effects of this invention: This invention proposes a torsion spring anti-collision device for an injection pen, including a housing 10, the front end of which is the proximal end and the rear end of which is the distal end. One end of the torsion spring 70 is connected to the dosage scale support 60, and the other end is connected to the spring fixing structure 20. The torsion spring mounting groove 23 of the spring fixing structure 20 is shortened near the side wall of the torsion spring 70 until there is no obstruction when the torsion spring hook 71 of the torsion spring 70 is inserted into the torsion spring mounting groove 23. At the same time, the torsion spring mounting groove 23 is gradually enlarged away from the side wall of the torsion spring 70 along the travel trajectory of the torsion spring hook 71 of the torsion spring 70. Due to the size and shape of the torsion spring mounting groove 23 and the torsion spring 70 being installed on the injection pen, the device provides a more comprehensive anti-collision device. The shape of the pen under stress is basically consistent, especially when the torsion spring hook 71 of the torsion spring 70 is installed on the spring fixing structure 20. The direction of the torsion spring hook 71 entering the torsion spring mounting groove 23 is completely consistent, so that the torsion spring 70 will not deform due to the force of the torsion spring hook 71, reducing the installation difficulty of the torsion spring 70, reducing costs, and avoiding the additional radial force generated during the storage process when the torsion spring 70 is subjected to radial compression after the torsion spring hook 71 is installed, which would cause the torsion spring 70 to deform and explode. At the same time, it avoids the phenomenon that the injection button 80 cannot rebound, avoids failure caused by the deformation of the torsion spring 70, thereby improving injection accuracy, improving structural reliability, and reducing failure rate.

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A torsion spring anti-collision device for an injection pen, comprising a housing (10), the front end of the housing (10) being a proximal end and the rear end of the housing (10) being a distal end, the distal end of the housing (10) being provided with a spring fixing structure (20), a screw sleeve (30) being sleeved inside the housing (10), the screw sleeve (30) passing through an adjustment knob (50) and sleeved with an injection button (80), a torsion spring (70) and a dosage scale support (60) being sleeved on the outer periphery of the screw sleeve (30), one end of the torsion spring (70) being connected to the dosage scale support (60), and the other end being connected to the spring fixing structure (20), characterized in that: The spring fixing structure (20) is provided with a torsion spring mounting groove (23), and one end of the torsion spring (70) is provided with a torsion spring hook (71). The width of the torsion spring mounting groove (23) gradually increases from the insertion of the torsion spring hook (71). The outer periphery of the spring fixing structure (20) is provided with a plurality of first hooks (21). The corresponding position of the far end of the housing (10) is provided with a first slot (11) that is engaged with it. The first hook (21) is matched and engaged with the first slot (11). The torsion spring hook (71) of the torsion spring (70) always travels along the torsion spring mounting groove (23) of the spring fixing structure (20) close to the side wall of the torsion spring (70).

2. The torsion spring anti-collision device for the injection pen as described in claim 1, characterized in that: The outer wall of the torsion spring mounting groove (23) gradually increases from the insertion of the torsion spring hook (71).

3. The torsion spring anti-collision device for the injection pen as described in claim 2, characterized in that: The torsion spring mounting groove (23) is enlarged by opening the groove in an involute pattern.

4. The torsion spring anti-collision device for the injection pen as described in claim 3, characterized in that: The bottom of the torsion spring mounting groove (23) is provided with a limiting step (24), and the connection between the torsion spring (70) and the torsion spring (70) is provided with a most curved arc surface (72). When the torsion spring (70) and the spring fixing structure (20) are installed, the most curved arc surface (72) and the free end of the limiting step (24) are attached.

5. The torsion spring anti-collision device for the injection pen as described in claim 1, characterized in that: The free end of the inner wall of the torsion spring mounting groove (23) near the side wall of the torsion spring (70) is provided with a guide surface (25) for guiding the torsion spring mounting groove (23) into the torsion spring mounting groove (23) when the torsion spring hook (71) of the torsion spring (70) enters.

6. The torsion spring anti-collision device for the injection pen as described in claim 5, characterized in that: The guide surface (25) is offset from the torsion spring mounting groove (23), and the torsion spring hook (71) for the torsion spring (70) does not interfere with the guide surface (25).

7. The torsion spring anti-collision device for the injection pen as described in claim 1, characterized in that: The outer periphery of the spring fixing structure (20) is also provided with a first protrusion (22), and the corresponding position of the far end of the housing (10) is provided with a first notch (12). When the housing (10) and the spring fixing structure (20) are matched and installed, the first protrusion (22) is just engaged with the first notch (12), thereby enhancing the connection between the spring fixing structure (20) and the housing (10).

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