Dose setting and correcting structure and injection device

Abstract

The invention relates to the technical field of pen type injection devices, in particular to a dose setting and correcting structure and an injection device.The dose setting and correcting structure comprises a shell, a dose setting ring and a dose setting ratchet wheel; a bidirectional ratchet wheel meshing tooth groove is formed in the shell; the dose setting ring comprises a dose setting knob and a driving arm; a bent arm and a driving bump are arranged outside the dose setting ratchet wheel, and bidirectional ratchet wheel teeth are arranged on the bent arm; the two-way ratchet teeth are meshed with the two-way ratchet meshing tooth grooves; when the dose setting knob rotates clockwise, the driving arm pushes the driving convex block to rotate to force the two-way ratchet teeth to be separated from the current two-way ratchet meshing tooth groove to be meshed with the next two-way ratchet meshing tooth groove, and dose setting is completed; and during reverse rotation, the driving arm synchronously rotates to press the bent arm, and the bidirectional ratchet teeth are forced to be separated from the current bidirectional ratchet meshing tooth groove to be meshed with the previous bidirectional ratchet meshing tooth groove, so that dose revision is completed. Correction can be carried out under the condition that the dosage is set mistakenly, the injection accuracy is improved, and the use friendliness of the injection device is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pen-type injection devices, and in particular to a dose setting and correction structure and an injection device. Background Art

[0002] Currently, there are disposable mechanical injection pens on the market, primarily used for administering single-dose (small) injections at regular intervals (e.g., weekly). There are also multi-disposable mechanical injection pens, primarily used for administering multiple doses at a more frequent interval (e.g., daily). Compared to single-disposable pens, multi-disposable mechanical injection pens offer lower costs, flexible dosage adjustments, and can be discarded after a cycle or a certain number of injections. Therefore, multi-disposable mechanical injection pens are more suitable for practical applications.

[0003] There are different types of products on the market. Regarding dose setting, the dose setting ring of a typical multi-shot mechanical injection pen rotates and extends out of the pen as the setting is set, requiring active injection propulsion after setting. There is no self-driven injection mechanism. Other injection pens with self-driven injection mechanisms can maintain the setting ring in place when setting the dose, but often lack a dose correction function. This means that if the user sets the dose incorrectly, they cannot correct it, resulting in inaccurate dose injection.

[0004] Thus, the present invention provides a dose setting and correction arrangement and injection device. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned technical problems existing in the prior art, the present invention provides a dose setting and correction structure and an injection device.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a dose setting and correction structure, comprising:

[0008] housing, dose setting ring, dose setting ratchet;

[0009] A bidirectional ratchet meshing tooth groove is provided on the inner wall of one end of the housing, and the dose setting ring includes a dose setting knob and a drive arm provided on the inner wall of the dose setting knob; a bent arm and a drive protrusion are provided on the outer wall of the dose setting ratchet, and the bent arm is provided with bidirectional ratchet teeth;

[0010] At least a portion of one end of the housing is disposed between the dose setting knob and the drive arm, the dose setting knob being configured to rotate relative to the housing;

[0011] The dose setting ratchet is disposed inside the housing, and the drive arm is disposed between the curved arm and the drive projection;

[0012] The bidirectional ratchet teeth are configured to mesh with the bidirectional ratchet meshing teeth;

[0013] When the dose setting knob is rotated clockwise by one unit, the drive arm rotates synchronously to abut against and push the drive protrusion to rotate, causing the bending arm to elastically deform, forcing the bidirectional ratchet teeth to disengage from the currently engaged bidirectional ratchet meshing groove and enter and engage with the next bidirectional ratchet meshing groove, completing the setting of one unit dose;

[0014] When the dose setting knob is rotated counterclockwise by one unit, the drive arm rotates synchronously to press the bending arm, causing the bending arm to undergo elastic deformation, forcing the bidirectional ratchet teeth to disengage from the currently engaged bidirectional ratchet meshing tooth groove, retract to the previous bidirectional ratchet meshing tooth groove and engage with it, completing the retraction revision of one unit dose.

[0015] Furthermore, both sides of the bidirectional ratchet meshing tooth groove are inclined surfaces, wherein the angle between the inclined surface facing the dose setting rotation direction and the tangential direction is smaller than the angle between the inclined surface away from the dose setting rotation direction and the tangential direction.

[0016] Furthermore, an annular rib is provided on the outer wall of the shell, and a shell limiting groove is provided on the inner wall of the dose setting ring. The annular rib is embedded in the shell limiting groove to achieve the clamping connection between the shell and the dose setting ring.

[0017] Furthermore, a plurality of grooves are arranged on the outer wall of the dose setting ring along the axial direction.

[0018] Furthermore, the dose setting ring comprises an outer cylinder and an inner cylinder, the outer cylinder is sleeved on the inner cylinder, and the outer cylinder and the inner cylinder are connected by a connecting plate;

[0019] The driving arm is arranged on the outer wall of the inner cylinder, and the upper end of the outer shell is embedded between the outer cylinder and the inner cylinder.

[0020] Furthermore, two driving protrusions and two bending arms are provided on the outer wall of the dose setting ratchet, and the two driving protrusions and the two bending arms are arranged alternately.

[0021] Furthermore, the inner wall of the dose setting ratchet is provided with meshing teeth, and the meshing teeth are used to engage the drive assembly to drive the drive assembly to complete the accumulation of force for dose setting.

[0022] Furthermore, a drive assembly is provided inside the dose setting ratchet, the drive assembly includes a drive rod, and the dose setting ratchet is engaged with the drive rod, so that when the dose setting ring rotates, the drive rod can be driven to rotate through the dose setting ratchet.

[0023] Furthermore, the driving rod includes a driving rod sleeve and a driving rod barrel, wherein the driving rod sleeve is sleeved outside the driving rod barrel and the driving rod sleeve and the driving rod barrel are connected; a torsion spring is provided between the driving rod sleeve and the driving rod barrel;

[0024] A torsion spring fixing ring is provided at one end of the driving rod, and the torsion spring fixing ring is fixed in the housing;

[0025] One end of the torsion spring is fixed to the torsion spring fixing ring, and the other end of the torsion spring is fixed to the driving rod, and the torsion direction of the torsion spring is set to rotate along the dose setting direction as a force.

[0026] Furthermore, a scale is provided between the housing and the driving rod, the inner wall of the housing is provided with a scale engaging thread, and the outer wall of the scale is provided with a housing engaging thread groove; the scale engaging thread is embedded in the housing engaging thread groove;

[0027] A driving rod engaging rib is provided on the inner wall of the scale, and a scale engaging rib groove is provided on the outer wall of the driving rod, wherein the driving rod engaging rib is embedded in the scale engaging rib groove;

[0028] A customer observation window is provided on the shell, and graduations are provided on the outer wall of the scale.

[0029] In a second aspect, the present invention provides an injection device comprising the above-mentioned dose setting and correction structure.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a dose setting and correction structure, wherein a bidirectional ratchet meshing tooth groove is provided on the inner wall of the shell, a drive arm is provided on the dose setting ring, a dose setting ratchet is provided on the inner wall of the dose setting ring, a drive protrusion and a bending arm are provided on the outer wall of the dose setting ratchet, and bidirectional ratchet teeth are provided on the bending arm.

[0032] When setting the dose, the dose setting ring is rotated, thereby driving the dose setting ratchet to rotate, and the dose setting is achieved through the deformation and engagement of the bending arm. When correcting the dose, the correction can also be achieved through the deformation and engagement of the bending arm. Therefore, it is possible to correct the dose setting error, improve the injection accuracy, and make the injection device more user-friendly.

[0033] In addition, the deformation of the bending arm in the present invention is an active deformation. When the dose is corrected, the driving arm is first squeezed to deform the bending arm, and then the bidirectional ratchet teeth and the bidirectional ratchet meshing grooves are re-engaged, so that the bidirectional ratchet teeth are not easily damaged. It is particularly suitable for setting and correcting large doses and frequent settings and corrections.

[0034] In addition, during the dose setting and dose correction process of the present invention, a "click-click" prompt sound can be generated through the engagement structure between the dose setting ratchet and the housing, making the present invention have an excellent interactive and friendly design. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is an axonometric drawing of the present invention;

[0036] Figure 2 A front view of the dose setting ring;

[0037] Figure 3 A bottom view of the dose setting ring;

[0038] Figure 4 An axonometric view of the internal structure of the dose setting ring;

[0039] Figure 5 A schematic diagram of the structure of the dose setting ratchet;

[0040] Figure 6 is an axonometric view of the torsion spring fixing ring;

[0041] Figure 7 is an axonometric view of the driving rod;

[0042] Figure 8 is a diagram of the internal structure of the driving rod;

[0043] Figure 9 is an axonometric drawing of the scale;

[0044] Figure 10 is an axonometric drawing of the housing;

[0045] Figure 11 is a schematic diagram of the internal structure of the housing;

[0046] Figure 12 is a top view of the housing;

[0047] Figure 13 is an axonometric view of the injection button;

[0048] Figure 14 is a cross-sectional view of the connection structure between the dose setting ring, the dose setting ratchet and the housing;

[0049] Figure 15 Schematic diagram of the internal structure after dose setting.

[0050] Reference numerals:

[0051] 1. Injection button, 101, buckle; 2. Compression spring;

[0052] 3. Dose setting ring, 301. Drive arm, 302. Injection button end surface, 303. Housing limit groove;

[0053] 4. Torsion spring fixing ring, 401. Torsion spring limiting groove, 402. Scale end limiting surface, 403. Shell limiting rib;

[0054] 5. Driving rod, 501. Dose setting ring meshing teeth, 502. Card strip, 503. Scale meshing rib groove, 504. Torsion spring lower limit groove;

[0055] 6. Putting;

[0056] 7. Torsion spring;

[0057] 8. Scale, 801. Engaging thread groove of housing, 802. Engaging rib of driving rod, 803. End surface, 804. Zero position limit surface of scale;

[0058] 9. Housing, 901. Bidirectional ratchet meshing tooth groove, 902. Scale meshing thread, 903. Observation window, 904. Annular rib, 905. Torsion spring fixing ring buckle hole, 906. Medicine bottle holder fixing groove;

[0059] 10. Dose setting ratchet, 1001. Drive protrusion, 1002. Bidirectional ratchet teeth, 1003. Drive rod engaging teeth, 1004. Bending arm. DETAILED DESCRIPTION

[0060] The technical solution of the present invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0061] It should be noted that, unless otherwise specifically stated, the relative arrangements of components and steps, and numerical expressions set forth in these embodiments should not be construed as limiting the scope of the present invention.

[0062] The following description of exemplary embodiments is merely illustrative and is not intended to limit the present invention, its application, or use in any sense. Technologies, methods, and apparatus known to those skilled in the art may not be discussed in detail herein, but to the extent applicable, such technologies, methods, and apparatuses should be considered part of this specification.

[0063] Example 1

[0064] This embodiment provides a dose setting and correction structure, including an injection button 1, a compression spring 2, a dose setting ring 3, a dose setting ratchet 10, a torsion spring fixing ring 4, a drive rod 5, a push rod 6, a torsion spring 7, a scale 8, and a housing 9. Figure 1 As shown, the housing 9 is provided outside the body of the injection device, the dose setting ring 3 is provided on the housing 9 and is rotatably connected to the housing 9, and the dose setting ring 3 is configured to set the dose by rotating the dose setting ring 3 in a forward direction relative to the housing 9, and to correct the dose by rotating the dose setting ring 3 in a reverse direction relative to the housing 9.

[0065] A drive rod 5 is disposed within the housing 9, and the push rod 6 is disposed within the drive rod 5; a dose setting ratchet 10 is disposed within the dose setting ring 3 and sleeved onto the outer portion of the upper end of the drive rod 5; the drive rod 5 engages with the dose setting ratchet 10, and when the dose setting ring 3 rotates, the dose setting ratchet 10 drives the drive rod 5 to rotate; an injection button 1 is disposed at one end of the housing 9. When the injection button 1 is triggered (pressed), the drive rod 5 reverses and drives the push rod 6 to move toward the vial, thereby achieving injection.

[0066] like Figures 2 to 4 The figure shows the structure of the dose setting ring 3. The dose setting ring 3 comprises a two-layer structure, specifically an inner cylinder and an outer cylinder. The outer cylinder is sleeved on the outside of the inner cylinder, and the two are connected by a connecting plate in the middle. The outer cylinder is connected to the outer shell. The specific connection structure is as follows: an outer shell limiting groove 303 is provided on the lower inner wall of the outer cylinder, and a corresponding annular rib 904 is provided on the outside of the outer shell 9. The annular rib 904 is embedded in the outer shell limiting groove 303 to realize the connection between the outer shell 9 and the dose setting ring 3. The outer cylinder is the dose setting knob, and the dose is set and corrected by rotating the outer cylinder.

[0067] In the space between the outer cylinder and the inner cylinder, a driving arm 301 is provided below the connecting plate. The clockwise direction is the advancing direction of the dose setting. The front end of the driving arm 301 abuts against the driving protrusion 1001 of the dose setting ratchet 10 .

[0068] When the housing 9 is connected to the dose setting ring 3 , the upper end of the housing 9 is inserted into the space between the outer cylinder and the inner cylinder of the dose setting ring 3 .

[0069] In addition, the upper end of the inner cylinder of the dose setting ring 3 is an injection button stop surface 302 , which is used to limit the injection button 1 when it is pressed.

[0070] The outer surface of the dose setting ring 3 is further provided with an axial groove to increase the friction when the dose setting ring is rotated.

[0071] Figure 5FIG2 is a structural diagram of the dose setting ratchet 10. Drive rod engaging teeth 1003 are provided on the inner wall of the dose setting ratchet 10 for driving the drive rod 5 to rotate. A curved arm 1004 is provided on the outer wall of the dose setting ratchet 10. The curved arm 1004 is a structure with one end fixed and the other end free, so it is deformable. The curved arm 1004 extends in a direction opposite to the dose setting rotation direction.

[0072] A bidirectional ratchet tooth 1002 is provided on the outside of the bending arm 1004. In this embodiment, two bending arms 1004 are provided, and a bidirectional ratchet tooth 1002 is provided on each bending arm 1004; a bidirectional ratchet meshing tooth groove 901 is provided on the inner wall of one end of the shell 9, and the bidirectional ratchet meshing tooth groove 901 is engaged with the bidirectional ratchet tooth 1002.

[0073] Two drive protrusions 1001 are also provided on the outer wall of the dose setting ratchet 10, with the two drive protrusions 1001 and the two curved arms 1004 being arranged alternately. Furthermore, when setting a dose, the front end of the drive arm 301 drives the drive protrusion 1001 to rotate, thereby driving the dose setting ratchet 10 to rotate. The curved arms 1004 of the dose setting ratchet 10 are blocked by the bidirectional ratchet meshing tooth grooves 901, causing the curved arms 1004 to deform, causing the bidirectional ratchet teeth 1002 to engage with the next bidirectional ratchet meshing tooth grooves 901. During this deformation and engagement process, a "clicking" sound is produced, enhancing the user-friendly experience.

[0074] like Figure 6 The structure of the torsion spring retaining ring 4 is shown. The torsion spring retaining ring 4 is disposed inside the upper end of the housing 9 and sleeved over the upper end of the driving rod 5. A torsion spring retaining groove 401 is provided on the upper surface of the torsion spring retaining ring 4. A portion of the torsion spring retaining groove 401 is a through-hole structure, which is used to clamp one end of the torsion spring 7 into the torsion spring retaining groove 401. A scale end limit surface 402 is provided on the lower surface of the torsion spring retaining ring 4 to limit the scale 8. The outer surface of the torsion spring retaining ring 4 is provided with a housing limit rib 403. The housing limit rib 403 is a tooth-shaped structure that meshes with the two-way ratchet meshing groove 901. The housing limit rib 403 is embedded in the two-way ratchet meshing groove 901, thereby confining the torsion spring retaining ring 4 within the housing 9. In addition, a snap is provided on the outer wall of the torsion spring retaining ring 4. The snap is inserted into the torsion spring retaining ring snap hole 905 on the inner wall of the housing 9 to secure the torsion spring retaining ring 4 to the housing 9.

[0075] like Figure 7 and Figure 8The figure shows the structure of the driving rod 5. The driving rod 5 includes a driving rod sleeve and a driving rod barrel. The driving rod sleeve is sleeved on the outside of the driving rod barrel and the lower end of the driving rod sleeve is fixedly connected to the driving rod barrel. In this embodiment, the driving rod sleeve and the driving rod barrel are detachable connection structures. Specifically, a buckle is provided at the lower end of the driving rod sleeve, and a clip is provided on the outer wall of the driving rod barrel. The buckle and the clip are engaged with the clip to realize the connection between the driving rod sleeve and the driving rod barrel.

[0076] A torsion spring 7 is provided between the drive rod sleeve and the drive rod barrel; a torsion spring lower limit groove 504 is provided at the connection between the drive rod sleeve and the drive rod barrel, the lower end of the torsion spring 7 is clamped in the torsion spring lower limit groove 504, and the torsion direction of the torsion spring 7 is set to rotate along the dose setting direction as animal force.

[0077] The top outer wall of the drive rod 5 is provided with a dose setting ring engagement tooth 501 , which is engaged with the drive rod engagement tooth 1003 .

[0078] A plurality of scale engaging rib grooves 503 extending in the axial direction are provided on the outer wall of the driving rod 5, and a driving rod engaging rib 802 is provided on the inner wall of the scale 8. The driving rod engaging rib 802 is embedded in the scale engaging rib groove 503, so that when the driving rod 5 rotates, the scale 8 can rotate synchronously with the driving rod 5.

[0079] like Figure 8 As shown, a clamping strip 502 is provided on the inner wall of the upper end of the driving rod 5 for clamping with the injection button 1 .

[0080] like Figure 9 The figure shows the structure of the scale 8. The outer wall of the scale 8 is provided with a shell engaging thread groove 801, and the inner wall of the shell 9 is provided with a scale engaging thread 902. The scale engaging thread 902 is embedded in the shell engaging thread groove 801; thus, the radial rotational movement of the scale 8 can be converted into a combination of axial movement and radial rotation.

[0081] The outer wall of the scale 8 may be provided with graduations, and during dose setting, the scale 8 can display the set dose. A stop surface 803 is provided at the upper end of the scale 8. This stop surface 803 contacts the scale stop limit surface 402 of the torsion spring retaining ring 4, defining the upper end of the scale 8. A scale zero limit surface 804 is provided at the lower end of the scale 8, defining the lower end of the scale 8.

[0082] A driving rod engaging rib 802 extending in the axial direction is provided on the inner wall of the scale 8 and matches with the scale engaging rib groove 503 on the outer wall of the driving rod 5 .

[0083] like Figures 10 to 12The figure shows the structure of the housing 9. A bidirectional ratchet meshing tooth groove 901 is provided on the inner wall of the upper end of the housing 9. The bidirectional ratchet meshing tooth groove 901 meshes with the bidirectional ratchet teeth 1002 on the dose setting ratchet 10. During the dose setting and dose correction process, the deformation and engagement of the bending arm 1004 also produce a "clicking" sound between the bidirectional ratchet teeth 1002 and the bidirectional ratchet meshing tooth groove 901. This sound continues during the dose setting process, which is a very user-friendly design for dose setting interaction.

[0084] An annular rib 904 is provided on the outer wall of the upper end of the shell 9, and a torsion spring fixing ring snap hole 905 is provided on the outer wall of the shell 9 below the annular rib 904. An observation window 903 is provided on the shell below the torsion spring fixing ring snap hole 905, through which the scale 8 can be observed, and the dose size set can be observed.

[0085] A scale engaging thread 902 is provided on the inner wall of the shell 9, a medicine bottle holder fixing groove 906 is provided on the inner wall of the lower end of the shell 14, and a buckle is provided on the outer wall of the medicine bottle holder, which is snapped into the medicine bottle holder fixing groove 906 to realize the connection between the shell 9 and the medicine bottle holder.

[0086] like Figure 12 The figure shows a top view of the housing 9. Both sides of the bidirectional ratchet engagement tooth groove 901 are inclined surfaces relative to the radial direction of the housing 9. The angle between the inclined surface facing the dose setting rotation direction and the tangential direction is smaller than the angle between the inclined surface facing away from the dose setting rotation direction and the tangential direction.

[0087] like Figure 13 The diagram shows the structure of the injection button 1. Two clips 101 are located on the inside of the injection button 1. A gap exists between the clips 101, facilitating their deformation and engagement. The injection button 1 engages the drive rod 5 via the clips 101. Furthermore, a circular protrusion is provided on the outer surface of the injection button 1 to increase friction when pressing the injection button 1 and prevent slippage.

[0088] like Figure 1 The figure shows the initial state of the dose setting and correction structure provided by this embodiment. The upper end of the housing 9 is connected to the dose setting ring 3. The scale 8 is disposed inside the housing 9. The drive rod 5 is disposed inside the scale 8. The push rod 6 is disposed inside the drive rod 5. The lower end of the drive rod 5 is provided with an autonomous drive assembly.

[0089] A torsion spring 7 is disposed in the side wall space of the drive rod 5. A torsion spring fixing ring 4 is disposed above and externally of the drive rod 5. A dose setting ratchet 10 is disposed above the torsion spring fixing ring 4, and the dose setting ratchet 10 is engaged with the dose setting ring 3. The outer wall of the drive rod 5 engages with the dose setting ratchet 10. An injection button 1 is disposed above the drive rod 5, and a compression spring 2 is disposed between the injection button 1 and the dose setting ring 3.

[0090] In the initial state, the scale zero position limit surface 804 of the scale 8 is limited by the autonomous driving assembly below the driving rod.

[0091] like Figure 14 Schematic diagram of the connection structure of the dose setting ring 3, the housing 9 and the dose setting ratchet 10 in the initial state. The upper end of the housing is arranged between the dose setting knob (the outer cylinder) and the drive arm 301. The dose setting knob is rotatable relative to the housing 9.

[0092] The dose setting ratchet 10 is arranged inside the upper end of the housing 9, and the drive arm 301 is arranged between the bending arm 1004 and the driving protrusion 1001, and one end of the driving arm 301 abuts the driving protrusion 1001, and the other end abuts the bending arm 1004. In the initial state, the bending arm 1004 is in a natural state without bending deformation.

[0093] When the dose setting knob is rotated clockwise by one unit, the drive arm 301 rotates synchronously to abut against and push the drive protrusion 1001 to rotate, causing the bending arm 1004 to elastically deform, forcing the bidirectional ratchet teeth 1002 to disengage from the currently engaged bidirectional ratchet meshing tooth groove 901 and enter and mesh with the next bidirectional ratchet meshing tooth groove 901, completing the setting of one unit dose;

[0094] When the dose setting knob is rotated counterclockwise by one unit, the drive arm 301 rotates synchronously to press the bending arm 1004, causing the bending arm 1004 to undergo elastic deformation, forcing the bidirectional ratchet teeth 1002 to disengage from the currently engaged bidirectional ratchet meshing tooth groove 901, retract to the previous bidirectional ratchet meshing tooth groove 901 and engage with it, completing the retraction revision of one unit dose.

[0095] The specific principle is: when the dose setting knob is rotated clockwise, the front end of the drive arm 301 pushes the drive protrusion 1001 to rotate, and the bent arm 1004 elastically deforms under the obstruction of the bidirectional ratchet meshing tooth groove 901, causing the bidirectional ratchet teeth 1002 to disengage from the currently engaged bidirectional ratchet meshing tooth groove 901 and enter the next bidirectional ratchet meshing tooth groove 901 and mesh with it. In the continuous deformation and meshing cycle, until the dose setting knob stops rotating, the bidirectional ratchet teeth 1002 pass through multiple bidirectional ratchet meshing tooth grooves 901 and mesh with the new bidirectional ratchet meshing tooth groove 901, completing the dose setting.

[0096] When the dose setting knob is rotated counterclockwise, the rear end of the drive arm 301 squeezes the flexure arm 1004, causing it to actively deform. Once the flexure arm 1004 is actively deformed, the torsion spring 7 exerts a certain reverse driving force, as dose adjustment typically occurs after setting. Under this driving force, the bidirectional ratchet teeth 1002 disengage from the currently engaged bidirectional ratchet meshing groove 901 and retract to the previous bidirectional ratchet meshing groove 901, engaging therewith. This continuous deformation and engagement cycle continues until the dose setting knob stops rotating. After passing through multiple bidirectional ratchet meshing grooves 901, the bidirectional ratchet teeth 1002 engage with the new bidirectional ratchet meshing groove 901, completing the dose adjustment. During the adjustment process, the torsion spring 7 also releases its corresponding driving force, and the remaining driving force of the torsion spring 7 after the adjustment completes the subsequent injection process.

[0097] Since the driving arm 301 compresses the bending arm 1004 to deform, the dose can be corrected with a smaller reversal force, which makes it less likely to damage the bidirectional ratchet teeth 1002. This is particularly suitable for setting and correcting large doses and frequent settings and corrections, thereby improving the reliability of the injection device.

[0098] Figure 15 The figure shows the state of this embodiment after dose setting. The dose is set by rotating the dose setting ring 3 clockwise. After rotating the dose setting ring 3, the drive arm 301 pushes the drive protrusion 1001 to rotate; through the engagement of the drive rod engagement teeth 1003 and the dose setting ring engagement teeth 501, the dose setting ring 3 drives the drive rod 5 to rotate via the dose setting ratchet 10, and the upper end of the torsion spring 7 is clamped on the torsion spring fixing ring 4. The torsion spring fixing ring 4 is fixed by the housing 9 and cannot rotate. Therefore, the lower end of the torsion spring 7 rotates with the drive rod 5, completing the force storage of the torsion spring 7.

[0099] At the same time, the bidirectional ratchet teeth 1002 and the bidirectional ratchet meshing grooves 901 are engaged, and the dose setting is achieved through the deformation of the bending arm 1004 and the engagement cycle. In addition, since the angles of the inclined surfaces on both sides of the bidirectional ratchet meshing grooves 901 are different, the angle in the positive direction is small and the angle in the reverse direction is large, combined with the deformation of the bending arm 1004, square dose setting and reverse dose correction are achieved.

[0100] At the same time, after the dose setting ring 3 is rotated, the drive rod 5 rotates, driving the scale 8 to rotate. Since the scale 8 is engaged with the scale engagement thread 902 of the housing 9, the scale 8 moves axially and rotates radially. After the dose is set, the scale 8 moves a certain distance toward the torsion spring fixing ring 4. The scale on the scale 8, i.e., the dose setting amount, can be observed through the observation window 903.

[0101] Example 2

[0102] This embodiment provides an injection device, including the above-mentioned metering setting and correction structure and an autonomous driving component. The autonomous driving component is set at the lower end of the driving rod 5, and the autonomous driving component is used to drive the push rod to move toward the medicine bottle holder to achieve injection.

[0103] The above specific embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the scope of the technical solutions of the present invention, and all of these should be included in the scope of the claims of the present invention.

Claims

1. A dose setting and correction structure, characterized in that: include: housing, dose setting ring, dose setting ratchet; A bidirectional ratchet meshing tooth groove is provided on the inner wall of one end of the housing, and the dose setting ring includes a dose setting knob and a drive arm provided on the inner wall of the dose setting knob; a bent arm and a drive protrusion are provided on the outer wall of the dose setting ratchet, and the bent arm is provided with bidirectional ratchet teeth; At least a portion of one end of the housing is disposed between the dose setting knob and the drive arm, the dose setting knob being configured to rotate relative to the housing; The dose setting ratchet is disposed inside the housing, and the drive arm is disposed between the curved arm and the drive projection; The bidirectional ratchet teeth are configured to mesh with the bidirectional ratchet meshing teeth; When the dose setting knob is rotated clockwise by one unit, the drive arm rotates synchronously to abut against and push the drive protrusion to rotate, causing the bending arm to elastically deform, forcing the bidirectional ratchet teeth to disengage from the currently engaged bidirectional ratchet meshing groove and enter and engage with the next bidirectional ratchet meshing groove, completing the setting of one unit dose; When the dose setting knob is rotated counterclockwise by one unit, the drive arm rotates synchronously to press the bending arm, causing the bending arm to undergo elastic deformation, forcing the bidirectional ratchet teeth to disengage from the currently engaged bidirectional ratchet meshing tooth groove, retract to the previous bidirectional ratchet meshing tooth groove and engage with it, completing the retraction revision of one unit dose.

2. The dose setting and correction structure according to claim 1, characterized in that: Both sides of the bidirectional ratchet meshing tooth groove are inclined surfaces, wherein the angle between the inclined surface facing the dose setting rotation direction and the tangential direction is smaller than the angle between the inclined surface away from the dose setting rotation direction and the tangential direction.

3. The dose setting and correction structure according to claim 1, characterized in that: An annular rib is provided on the outer wall of the shell, and a shell limiting groove is provided on the inner wall of the dose setting ring. The annular rib is embedded in the shell limiting groove to achieve the clamping connection between the shell and the dose setting ring.

4. The dose setting and correction structure according to claim 1, characterized in that: A plurality of grooves are arranged on the outer wall of the dose setting ring along the axial direction.

5. The dose setting and correction structure according to claim 1, characterized in that: There are two driving protrusions and two bending arms on the outer wall of the dose setting ratchet, and the two driving protrusions and the two bending arms are arranged in a staggered manner.

6. The dose setting and correction structure according to claim 1, characterized in that: The inner wall of the dose setting ratchet is provided with meshing teeth, and the meshing teeth are used to engage the drive assembly to drive the drive assembly to complete the accumulation of force for dose setting.

7. The dose setting and correction structure according to claim 6, characterized in that: A drive assembly is disposed inside the dose setting ratchet, the drive assembly comprising a drive rod, and the dose setting ratchet is engaged with the drive rod, so that when the dose setting ring rotates, the drive rod can be driven to rotate via the dose setting ratchet.

8. The dose setting and correction structure according to claim 7, characterized in that: The driving rod comprises a driving rod sleeve and a driving rod barrel, wherein the driving rod sleeve is sleeved outside the driving rod barrel and the driving rod sleeve and the driving rod barrel are connected; a torsion spring is provided between the driving rod sleeve and the driving rod barrel; A torsion spring fixing ring is provided at one end of the driving rod, and the torsion spring fixing ring is fixed in the housing; One end of the torsion spring is fixed to the torsion spring fixing ring, and the other end of the torsion spring is fixed to the driving rod, and the torsion direction of the torsion spring is set to rotate along the dose setting direction as a force.

9. The dose setting and correction structure according to claim 8, characterized in that: A scale is provided between the housing and the driving rod, a scale engaging thread is provided on the inner wall of the housing, and a housing engaging thread groove is provided on the outer wall of the scale; the scale engaging thread is embedded in the housing engaging thread groove; A driving rod engaging rib is provided on the inner wall of the scale, and a scale engaging rib groove is provided on the outer wall of the driving rod, wherein the driving rod engaging rib is embedded in the scale engaging rib groove; A customer observation window is provided on the shell, and graduations are provided on the outer wall of the scale.

10. An injection device, characterized in that: The invention comprises the dose setting and correction structure according to any one of claims 1 to 9.

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