Dose accumulation mechanism

Abstract

The present application relates to a dose accumulation mechanism comprising: a drive worm provided with a drive rib; the matching component is connected with the driving worm in a sleeving manner; the integral worm gear is connected to the matching component and provided with a plurality of meshing grooves, and the meshing grooves are used for meshing of the driving ribs; the first limiting part is arranged on the driving worm or the matching part; the second limiting part is arranged on the integral worm gear; during dose setting, the driving worm can rotate relative to the matching part in the first direction to increase the dose and rotate in the second direction to decrease the dose; during dose injection, the drive worm is in anti-rotation connection with the mating member; when the first limiting part abuts against the second limiting part, a stop position of the integral worm gear is formed, and when the integral worm gear is located at the stop position, the driving worm is prevented from continuously moving in the first direction relative to the matching component. According to the invention, the movement of the integral worm gear can be limited, so that the maximum dose which can be set can be limited.

Description

Technical Field

[0001] The present application relates to the technical field of injection devices, and in particular to a dose accumulation mechanism. Background Art

[0002] When injecting drugs, a specific injection device is used, which is usually called a pen-type syringe or an injection pen. The user can set the dose based on the need and inject the set dose. At the same time, the process of the user setting the dose and then injecting the set dose is regarded as a complete injection.

[0003] In the actual use process, the injection device is equipped with a cartridge containing drugs. As the user injects successively, the remaining dose of the drug in the cartridge gradually decreases. As the remaining dose in the cartridge continuously decreases, it may occur that the dose set by the user based on the need is greater than the remaining dose of the drug. Therefore, a structure for limiting the maximum value of the dose setting needs to be configured in the injection device. Utility Model Content

[0004] In order to limit the maximum dose that can be set for the injection device, the present application provides a dose accumulation mechanism.

[0005] The dose accumulation mechanism provided by the present application adopts the following technical solutions:

[0006] A dose accumulation mechanism includes: a driving worm that can rotate around a first axis, and the driving worm is provided with driving ribs; a matching component that is sleeved with the driving worm and can rotate around the first axis; an integral worm wheel that is connected to the matching component and can rotate relative to the matching component around a second axis, the second axis intersects with the first axis, the integral worm wheel is provided with a plurality of meshing grooves, the plurality of meshing grooves are arranged at intervals along the circumferential direction of the second axis, and the meshing grooves are used for the driving ribs to engage; a first limiting part that is arranged on the driving worm or the matching component; a second limiting part that is arranged on the integral worm wheel; wherein, during dose setting, the driving worm can rotate relative to the matching component in a first direction to increase the dose and rotate in a second direction to decrease the dose, and the driving ribs are used to drive the integral worm wheel to rotate; during dose injection, the driving worm and the matching component are anti-rotationally connected; when the first limiting part abuts against the second limiting part, it constitutes the termination position of the integral worm wheel, and when the integral worm wheel is in the termination position, it prevents the driving worm from continuing to move in the first direction relative to the matching component.

[0007] By adopting the above technical solution, during the dose setting period, the driving worm and the mating component rotate relative to each other so that the integral worm gear rotates along the second axis, and the rotation angle of the integral worm gear corresponds to the dose setting amount. During the dose injection period, the driving worm, the mating component, and the integral worm gear all remain relatively stationary. Therefore, during a complete injection process, the integral worm gear can record the dose setting amount through its own rotation. Correspondingly, as the user performs successive injections, the integral worm gear can accumulate the total dose setting amount. Until the integral worm gear moves to the termination position formed by the first limiting portion and the second limiting portion abutting against each other, the integral worm gear is restricted from further rotating. At this time, the driving worm and the mating component cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose and further limiting the maximum cumulative set dose.

[0008] Further, the first limiting portion is provided on the driving worm. Define the movement direction of the first limiting portion when increasing the dose as the termination approaching direction. When the second limiting portion blocks the first limiting portion from continuing to move in the termination approaching direction, the termination position of the integral worm gear is formed.

[0009] During the actual use process, the action of dose setting is reflected in the relative rotation amount between the driving worm and the mating component, and the relative rotation amount between the driving worm and the mating component is converted into the rotation amount of the integral worm gear through the cooperation between the driving rib on the driving worm and the engaging groove on the integral worm gear. The cooperation between the driving rib on the driving worm and the engaging groove on the integral worm gear is similar to the cooperation between the worm thread and the worm gear tooth groove. The motion transmission from the driving worm to the integral worm gear belongs to a decelerating motion. Therefore, the dose represented by the first limiting portion moving one unit angle is smaller than the dose represented by the second limiting portion moving one unit angle. In actual manufacturing, there are inevitably dimensional errors. In the above solution, compared with limiting the movement of the second limiting portion to define the termination position, limiting the movement of the first limiting portion to define the termination position can reduce the adverse impact of dimensional errors on dose accumulation.

[0010] Further, the first limiting portion is configured as the end of the driving rib.

[0011] Further, it is provided in the engaging groove of the second limiting portion.

[0012] Further, the outer periphery of the integral worm gear includes an engaging arc section and a stop arc section. The engaging arc section is formed by the engaging grooves arranged at intervals. The side wall of the stop arc section serves as the second limiting portion for the first limiting portion to abut against.

[0013] Further, the first limiting portion is provided on the driving worm. Define the movement direction of the second limiting portion when increasing the dose as the terminating approaching direction. When the first limiting portion blocks the second limiting portion from continuing to move along the terminating approaching direction, the terminating position of the integrating worm gear is formed.

[0014] Further, the second limiting portion is configured as a stop bar extending radially along the integrating worm gear, and the first limiting portion is configured as a terminating abutting portion on the side wall of the driving worm.

[0015] Further, the first limiting portion is provided on the mating component. The first limiting portion is provided with opposite first stop surface and second stop surface. When the first stop surface abuts against the second limiting portion, the starting position of the integrating worm gear is formed. When the second stop surface abuts against the second limiting portion, the terminating position of the integrating worm gear is formed; wherein, when the integrating worm gear is at the starting position, it prevents the driving worm from continuing to move along the second direction relative to the mating component.

[0016] Further, the driving worm is sleeved outside the mating component. The driving rib is provided on the inner side wall of the driving worm, and the integrating worm gear is located inside the driving worm.

[0017] Further, the mating component is sleeved outside the driving worm. The driving rib is provided on the outer side wall of the driving worm, and the integrating worm gear is located outside the driving worm.

[0018] In summary, the present application has at least the following beneficial effects: During the dose setting period, the driving worm and the mating component rotate relative to each other so that the integrating worm gear rotates along the second axis, and the rotation angle of the integrating worm gear corresponds to the dose setting amount. During the dose injection period, the driving worm, the mating component, and the integrating worm gear all remain relatively stationary; thus, during a complete injection process, the integrating worm gear can record the dose setting amount through its own rotation. Correspondingly, as the user performs successive injections, the integrating worm gear can accumulate the total dose set until the integrating worm gear moves to the terminating position formed by the first limiting portion and the second limiting portion abutting against each other. At this time, the integrating worm gear is restricted from further rotating, and at this time, the driving worm and the mating component cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of an injection device with a dose accumulation mechanism in an embodiment of the present application Figure 1 ;

[0020] Figure 2 is a schematic diagram of an injection device with a dose accumulation mechanism in an embodiment of the present application Figure 2 ;

[0021] Figure 3 It is a schematic diagram of the integral worm wheel and the mating components in the embodiment of the present application Figure 1 ;

[0022] Figure 4 It is a schematic diagram of the integral worm wheel and the driving worm in the embodiment of the present application;

[0023] Figure 5 It is a schematic diagram of the integral worm wheel and the mating components in the embodiment of the present application Figure 2 ;

[0024] Figure 6 It is a schematic diagram for showing the starting position formed by the integral worm wheel and the mating components in the embodiment of the present application;

[0025] Figure 7 It is a schematic diagram for showing the ending position formed by the integral worm wheel and the mating components in the embodiment of the present application;

[0026] Figure 8 It is a schematic diagram for showing the starting position formed by the integral worm wheel and the driving worm in the embodiment of the present application Figure 1 ;

[0027] Figure 9 It is a schematic diagram for showing the ending position formed by the integral worm wheel and the driving worm in the embodiment of the present application Figure 1 ;

[0028] Figure 10 It is a schematic diagram for showing the starting position formed by the integral worm wheel and the driving worm in the embodiment of the present application Figure 2 ;

[0029] Figure 11 It is a schematic diagram for showing the integral worm wheel in the embodiment of the present application Figure 1 ;

[0030] Figure 12 It is a schematic diagram for showing the integral worm wheel in the embodiment of the present application Figure 2 ;

[0031] Figure 13 It is a schematic diagram for showing the ending position formed by the integral worm wheel and the driving worm in the embodiment of the present application Figure 2 ;

[0032] Figure 14 It is a cross-sectional view for showing the dose accumulation mechanism and the clutch element in the embodiment of the present application;

[0033] Figure 15 It is an exploded schematic diagram for showing the dose accumulation mechanism and the clutch element in the embodiment of the present application;

[0034] Figure 16It is a schematic diagram for showing the axial tooth ring on the mating component in the embodiment of the present application;

[0035] Figure 17 It is a schematic diagram for showing the mating teeth on the clutch element in the embodiment of the present application.

[0036] Explanation of reference numerals:

[0037] 1. Driving worm; 11. Driving rib; 12. Ratchet tooth ring; 13. Initial abutting part; 14. Final abutting part; 15. First starting part; 16. First ending part; 2. Mating component; 21. Radial through groove; 22. Axial tooth ring; 23. Stop bar; 231. First stop surface; 232. Second stop surface; 24. Support seat; 3. Integral worm gear; 31. Meshing teeth; 32. Meshing groove; 33. Rotating shaft; 34. Ridge; 341. First abutting surface; 342. Second abutting surface; 35. Stop bar; 36. Second starting part; 37. Second ending part; 38. Meshing arc segment; 39. Stop arc segment; 4. Clutch element; 41. Ratchet arm; 42. Mating teeth; 421. Right-angle surface; 422. Inclined surface; 5. Driving rod; 6. Push rod; 7. Housing; 8. Cartridge bottle; 81. Movable piston; 9. Button; 10. Spring. Detailed implementation manners

[0038] The embodiments of the present utility model will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation of the present utility model.

[0039] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model. In addition, features defined with "first", "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise stated, the meaning of "a plurality" is two or more.

[0040] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0041] Currently, based on the transmission principle of worm and worm gear, there is conceived a dose accumulation structure for accumulating a set dose, which specifically includes a driving worm, a mating component, and an integrating worm wheel. Among them, the driving worm and the mating component can rotate relative to each other during dose setting, and during dose injection, the driving worm and the mating component form an anti-rotation coupling to rotate synchronously. At the same time, the integrating worm wheel is rotatably mounted on the mating component, and the engaging grooves of the integrating worm wheel are engaged with the driving ribs of the driving worm.

[0042] In the above solution, during dose adjustment, the driving ribs on the driving worm drive the integrating worm wheel to rotate relative to the mating component, and during dose injection, the driving worm, the mating component, and the integrating worm wheel remain relatively stationary. Thus, the set dose of the user can be accumulated by the rotation of the integrating worm wheel. Correspondingly, in order to make the accumulated set dose not exceed the total amount of the drug contained in the cartridge, a stroke limiting structure for restricting the continued movement of the integrating worm wheel needs to be configured in the above dose accumulation structure to limit the maximum settable accumulated dose.

[0043] The embodiment of the present application discloses a dose accumulation mechanism, which can limit the movement of the integrating worm wheel 3 to limit the maximum settable accumulated dose.

[0044] Refer to Figure 1 and Figure 2 , the dose accumulation mechanism includes a driving worm ①, a mating component ②, an integrating worm wheel ③, a first limiting portion, and a second limiting portion.

[0045] Among them, the driving worm ① can rotate around a first axis, the first axis is the central axis of the housing ⑦, and the driving worm ① is provided with driving ribs 11, and the driving ribs 11 extend around the first axis on the driving worm ①; the mating component ② is sleeved on the driving worm ①, and the mating component ② can rotate around the first axis; the integrating worm wheel ③ is connected to the mating component ②, and the integrating worm wheel ③ can rotate relative to the mating component ② around a second axis, the second axis is the central axis of the integrating worm wheel ③, and the second axis is arranged intersecting with the first axis; at the same time, the integrating worm wheel ③ is provided with a plurality of engaging teeth 31, and the plurality of engaging teeth 31 are arranged at intervals along the circumferential direction of the second axis, so that an engaging groove 32 for the driving ribs 11 to engage is formed between two adjacent engaging teeth 31.

[0046] Specifically, during dose setting, the drive worm 1 and the mating member 2 are rotatable relative to each other, and dose setting includes increasing the dose and decreasing the dose; correspondingly, when the drive worm 1 rotates relative to the mating member 2 in the first direction, it is used to increase the dose, and when the drive worm 1 rotates relative to the mating member 2 in the second direction, it is used to decrease the dose, and the first direction is opposite to the second direction. At the same time, during the entire dose setting period, the drive rib 11 is used to cooperate with the meshing teeth 31 to drive the integral worm wheel 3 to rotate. During dose injection, the drive worm 1 and the mating member 2 are anti-rotationally connected so that the drive worm 1 and the mating member 2 rotate synchronously or are stationary synchronously, and during this period, the integral worm wheel 3 is stationary relative to the drive worm 1 and the mating member 2.

[0047] In addition, the integral worm wheel 3 has a starting position and an ending position of movement, and the movement stroke of the integral worm wheel 3 between the starting position and the ending position corresponds to the total amount of the drug that the injection device can inject; it can be understood that the integral worm wheel 3 can move relative to the drive worm 1 and can also move relative to the mating member 2. To limit the further rotation of the integral worm wheel 3 at the ending position, the first limiting portion is disposed on the drive worm 1 or the mating member 2, and the second limiting portion is disposed on the integral worm wheel 3; when the first limiting portion abuts against the second limiting portion, it constitutes the ending position of the integral worm wheel 3, and when the integral worm wheel 3 is at the ending position, the integral worm wheel 3 is restricted from further rotating, and at this time, the drive worm 1 and the mating member 2 cannot further rotate in the direction of increasing the dose.

[0048] With the above solution, during dose setting, the drive worm 1 and the mating member 2 rotate relative to each other so that the integral worm wheel 3 rotates along the second axis, and the rotation angle of the integral worm wheel 3 corresponds to the dose setting amount. During dose injection, the drive worm 1, the mating member 2, and the integral worm wheel 3 all remain relatively stationary; in a complete injection process, the integral worm wheel 3 can record the dose setting amount through its own rotation. Correspondingly, as the user performs successive injections, the integral worm wheel 3 can accumulate the total amount of dose settings until the integral worm wheel 3 moves to the ending position, and the drive worm 1 and the mating member 2 cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose and further limiting the maximum cumulative set dose. At the same time, the amount of movement of the integral worm wheel 3 between the starting position and the ending position corresponds to the total amount of the drug that the injection device can inject. As the integral worm wheel 3 gradually moves from the starting position to the ending position, the remaining available movement amount between the integral worm wheel 3 and the ending position always corresponds to the remaining drug dose that can be injected in the injection device; therefore, it can be ensured that the dose set each time does not exceed the remaining drug dose that the injection device can inject, making the actual injection dose consistent with the set dose, avoiding the situation of injecting the wrong dose, and further ensuring that the drug injection obtains its corresponding use effect.

[0049] It should be noted that the movement stroke of the integral worm wheel 3 between the starting position and the ending position corresponds to the total amount of medicine that the injection device can inject, indicating that there is a corresponding relationship between the movement stroke of the integral worm wheel 3 and the total amount of medicine in the injection device. For the convenience of description, the movement stroke of the integral worm wheel 3 is defined as U, and the ratio of the set dose to the movement amount of the integral worm wheel 3 is defined as T, that is, the total set dose of the integral worm wheel 3 during its entire movement stroke is UT. At the same time, the total amount of medicine in the injection device is defined as S. In some specific embodiments, UT = S, indicating that the total set dose corresponding to the entire movement stroke of the integral worm wheel 3 is equal to the total amount of medicine in the injection device, so that the medicine in the injection device can be exactly completely injected during the last injection. In some other specific embodiments, UT < S, indicating that the total set dose corresponding to the entire movement stroke of the integral worm wheel 3 is less than the total amount of medicine in the injection device, so that there will still be some medicine remaining in the injection device after the last injection and not being injected. In some other specific embodiments, when the dose accumulation mechanism is assembled into the injection device, the mating dimensions are adjusted, which will cause the integral worm wheel 3 to move from the starting position to the ending position. Correspondingly, the movement amount of the integral worm wheel 3 during the assembly and adjustment is defined as u. In some embodiments, the equation (U - u)T = S is satisfied, that is, the medicine in the injection device can be exactly completely injected during the last injection. In some other embodiments, the inequality (U - u)T < S is satisfied, that is, there will still be some medicine remaining in the injection device after the last injection and not being injected.

[0050] Similarly, it should be noted that the intersecting arrangement of the first axis and the second axis means that the first axis and the second axis are not parallel, that is, the first axis and the second axis will not be in the same plane. Specifically, if the plane where the first axis is located is defined as the first plane, then the second axis will intersect the first plane at a point. In a specific embodiment, the first axis is configured to be perpendicular to the second axis so that the driving force transmission between the driving worm 1 and the integral worm wheel 3 has better transmission efficiency.

[0051] It can be understood that the driving worm 1 being sleeved with the mating part 2 can be that the driving worm 1 is sleeved outside the mating part 2, or the mating part 2 is sleeved outside the driving worm 1.

[0052] Refer to Figure 1 and Figure 3, in some embodiments, the driving worm 1 is sleeved outside the mating component 2. Among them, the driving worm 1 is generally cylindrical, and the driving rib 11 is disposed on the inner sidewall of the driving worm 1; the mating component 2 is generally cylindrical, and at least part of the mating component 2 is accommodated in the driving worm 1, and the integral worm wheel 3 is completely accommodated in the driving worm 1. At the same time, the integral worm wheel 3 is rotatably connected to the mating component 2 through a rotating shaft 33. Correspondingly, an avoidance area is provided on the mating component 2 to allow the integral worm wheel 3 to rotate without restriction. In some specific embodiments, the mating component 2 is provided with a radial through groove 21 in a direction perpendicular to the first axis and the second axis. The integral worm wheel 3 is installed in the radial through groove 21, and the radial through groove 21 serves as an avoidance area on the mating component 2 for the integral worm wheel 3 to freely rotate; moreover, the area of the integral worm wheel 3 provided with the engaging groove 32 installed in the radial through groove 21 can protrude from one notch of the radial through groove 21 and engage with the driving rib 11 on the inner sidewall of the driving worm 1.

[0053] In the above embodiments, during dose setting, the driving worm 1 rotates around the first axis while the mating component 2 remains stationary, and during dose injection, the driving worm 1 and the mating component 2 rotate synchronously. It can be understood that if it is defined that the driving worm 1 rotates clockwise relative to the housing 7 when increasing the dose and rotates counterclockwise relative to the housing 7 when decreasing the dose, then the driving worm 1 rotating along the first direction relative to the mating component 2 corresponds to the mating component 2 being stationary while the driving worm 1 rotates clockwise, and the driving worm 1 rotating along the second direction relative to the mating component 2 corresponds to the mating component 2 being stationary while the driving worm 1 rotates counterclockwise; moreover, the first direction is the clockwise direction and the second direction is the counterclockwise direction.

[0054] Refer to Figure 2 , Figure 4 and Figure 5 , in some other embodiments, the mating component 2 is sleeved outside the driving worm 1. Among them, the mating component 2 is generally cylindrical, the integral worm wheel 3 is completely accommodated in the mating component 2 and is outside the driving worm 1. At the same time, a support seat 24 is provided on the inner side of the mating component 2, and the integral worm wheel 3 is rotatably installed on the support seat 24 of the mating component 2; at least part of the driving worm 1 is accommodated in the mating component 2, and the driving rib 11 is disposed on the outer sidewall of the driving worm 1. Correspondingly, an activity cavity for the integral worm wheel 3 to freely rotate is formed between the driving worm 1 and the mating component 2; in some specific embodiments, there is a distance between the inner sidewall of the mating component 2 and the outer sidewall of the driving worm 1 provided with the driving rib 11, so that an annular cavity is formed between the driving worm 1 and the mating component 2, and this annular cavity serves as an activity cavity for the integral worm wheel 3 to freely rotate.

[0055] In the above embodiments, during dose setting, the mating member 2 rotates around the first axis while the driving worm 1 remains stationary, and during dose injection, the mating member 2 and the driving worm 1 rotate synchronously. If it is defined that the mating member 2 rotates clockwise relative to the housing 7 when increasing the dose and rotates counterclockwise relative to the housing 7 when decreasing the dose; it can be understood that the driving worm 1 rotates relative to the mating member 2 in the dose increasing direction corresponding to the driving worm 1 being stationary while the mating member 2 rotates clockwise, and the driving worm 1 rotates relative to the mating member 2 in the second rotation direction corresponding to the driving worm 1 being stationary while the mating member 2 rotates counterclockwise, and the first direction is the counterclockwise direction and the second direction is the clockwise direction.

[0056] It can be understood that the integrating worm wheel 3 can move relative to the driving worm 1 and can also move relative to the mating member 2. Correspondingly, the starting position of the integrating worm wheel 3 can be formed by the integrating worm wheel 3 and the driving worm 1, or can be formed by the integrating worm wheel 3 and the mating member 2. At the same time, the ending position of the integrating worm wheel 3 can be formed by the integrating worm wheel 3 and the driving worm 1, or can be formed by the integrating worm wheel 3 and the mating member 2.

[0057] In some embodiments, a abutting structure is provided between the integrating worm wheel 3 and the mating member 2 to form the starting position and / or the ending position of the integrating worm wheel 3.

[0058] Refer to Figure 6 , in some embodiments where the integrating worm wheel 3 and the mating member 2 cooperate to form the starting position, the integrating worm wheel 3 has two side walls oppositely arranged along the second axis. A rib 34 is provided on one of the side walls of the integrating worm wheel 3. The rib 34 can rotate with the integrating worm wheel 3, and the rib 34 has a first abutting surface 341; correspondingly, the mating member 2 is provided with a stop bar 23, and the stop bar 23 has a first stop surface 231. When the first abutting surface 341 of the rib 34 abuts against the first stop surface 231 of the stop bar 23, the integrating worm wheel 3 is stationary relative to the mating member 2 to form the starting position of the integrating worm wheel 3.

[0059] Refer to Figure 7 , in some embodiments where the integrating worm wheel 3 and the mating member 2 cooperate to form the ending position, the first limiting portion is provided on the mating member 2, and the second limiting portion is provided on the integrating worm wheel 3. Specifically, the integrating worm wheel 3 has two side walls oppositely arranged along the second axis. A rib 34 serving as the second limiting portion is provided on one of the side walls of the integrating worm wheel 3. The rib 34 can rotate with the integrating worm wheel 3, and the rib 34 has a second abutting surface 342; correspondingly, the mating member 2 is provided with a stop bar 23 serving as the first limiting portion, and the stop bar 23 has a second stop surface 232. When the second abutting surface 342 of the rib 34 abuts against the second stop surface 232 of the stop bar 23, the integrating worm wheel 3 is stationary relative to the mating member 2 to form the ending position of the integrating worm wheel 3.

[0060] Refer toFigure 6 and Figure 7 , in some embodiments where the integral worm wheel 3 and the mating component 2 cooperate to form the starting position and the ending position, the first limiting portion is provided on the mating component 2, and the second limiting portion is provided on the integral worm wheel 3. Specifically, the integral worm wheel 3 has two side walls oppositely arranged along the second axis. On one of the side walls of the integral worm wheel 3, there is a rib 34 serving as the second limiting portion. The rib 34 can rotate with the integral worm wheel 3, and the rib 34 has opposite first abutting surfaces 341 and second abutting surfaces 342 along its moving direction; correspondingly, the mating component 2 is provided with a stop bar 23 serving as the first limiting portion, and the stop bar 23 has opposite first stopping surfaces 231 and second stopping surfaces 232. When the first abutting surface 341 of the rib 34 abuts against the first stopping surface 231 of the stop bar 23, the starting position of the integral worm wheel 3 is formed, and when the second abutting surface 342 of the rib 34 abuts against the second stopping surface 232 of the stop bar 23, the ending position of the integral worm wheel 3 is formed.

[0061] In some other embodiments, a abutting structure is provided between the integral worm wheel 3 and the driving worm 1 to form the starting position or the ending position of the integral worm wheel 3. Specifically, the driving worm 1 is provided with a first limiting portion, and the first limiting portion moves around the first axis with the driving worm 1. The integral worm wheel 3 is provided with a second limiting portion, and the second limiting portion moves around the second axis with the integral worm wheel 3; when the first limiting portion abuts against the second limiting portion, the starting position is formed, or when the first limiting portion abuts against the second limiting portion, the ending position is formed.

[0062] In some embodiments where the integral worm wheel 3 and the driving worm 1 cooperate to form the starting position, the starting position is formed by the first limiting portion blocking the second limiting portion from continuing to move around the second axis with the integral worm wheel 3; referring to Figure 8 , in a specific embodiment, the first limiting portion includes an initial abutting portion 13 provided on the side wall of the driving worm 1. The initial abutting portion 13 can be configured as an arc-shaped convex block, or can be configured as a convex ring surrounding the driving worm 1, or can also be a part of the side wall of the driving worm 1. The second limiting portion includes a stop bar 35 extending radially of the integral worm wheel 3; when the stop bar 35 moves with the integral worm wheel 3 to abut against the initial abutting portion 13, the integral worm wheel 3 is prevented from further rotating, thereby forming the starting position of the integral worm wheel 3.

[0063] In some embodiments where the integral worm wheel 3 and the driving worm 1 cooperate to form the ending position, the ending position is formed by the first limiting portion blocking the second limiting portion from continuing to move around the second axis with the integral worm wheel 3; referring to Figure 9, in a specific embodiment, the first limiting portion includes a termination abutting portion 14 provided on the side wall of the driving worm 1. The termination abutting portion 14 can be configured as an arc-shaped convex block, or can be configured as a convex ring surrounding the driving worm 1, or can also be a part of the side wall of the driving worm 1. The second limiting portion includes a stop bar 35 extending radially of the integral worm wheel 3; when the stop bar 35 moves with the integral worm wheel 3 to abut against the termination abutting portion 14, the integral worm wheel 3 is prevented from further rotating, thereby forming the termination position of the integral worm wheel 3.

[0064] In some other embodiments where the integral worm wheel 3 and the driving worm 1 cooperate to form the starting position, the starting position is formed by the second limiting portion blocking the first limiting portion from continuing to move around the first axis with the driving worm 1; refer to Figure 10 , in a specific embodiment, the first limiting portion includes a first starting portion 15, and the second limiting portion includes a second starting portion 36. Define the movement direction of the first starting portion 15 during the period of reducing the dose as the starting approaching direction. When the second starting portion 36 moves to block the first starting portion 15 from continuing to move in the starting approaching direction, the starting position of the integral worm wheel 3 is formed.

[0065] Specifically, in some embodiments, the first starting portion 15 is configured as the end of the driving rib 11.

[0066] Specifically, refer to Figure 11 , in some embodiments, meshing teeth 31 are provided on the entire circumference of the integral worm wheel 3, that is, the meshing teeth 31 are arranged in a complete circle on the main body of the integral worm wheel 3; correspondingly, the second starting portion 36 is provided between two adjacent meshing teeth 31. Refer to Figure 12 , in some other embodiments, the outer circumference of the integral worm wheel 3 includes a meshing arc segment 38 provided with meshing teeth 31 and a stop arc segment 39 not provided with meshing teeth 31; correspondingly, the side wall of the stop arc segment 39 serves as the second starting portion 36.

[0067] In some other embodiments where the integral worm wheel 3 and the driving worm 1 cooperate to form the starting position, the termination position is formed by the second limiting portion blocking the first limiting portion from continuing to move around the first axis with the driving worm 1; refer to Figure 13 , in a specific embodiment, the first limiting portion includes a first termination portion 16, and the second limiting portion includes a second termination portion 37; define the movement direction of the first termination portion 16 when increasing the dose as the termination approaching direction. When the second termination portion 37 moves to block the first termination portion 16 from continuing to move in the termination approaching direction, the termination position of the integral worm wheel 3 is formed.

[0068] Specifically, in some embodiments, the first termination portion 16 is configured as the end of the driving rib 11.

[0069] Specifically, refer to Figure 11, in some embodiments, meshing teeth 31 are provided on the entire circumference of the integrating worm wheel 3, that is, the meshing teeth 31 are arranged in a complete circle on the main body of the integrating worm wheel 3; correspondingly, the second termination portion 37 is provided between two adjacent meshing teeth 31. Refer to Figure 12 , in other embodiments, the outer circumference of the integrating worm wheel 3 includes a meshing arc segment 38 provided with meshing teeth 31 and a stop arc segment 39 not provided with meshing teeth 31; correspondingly, the side wall of the stop arc segment 39 serves as the second termination portion 37.

[0070] In a second aspect, embodiments of the present application disclose an injection device that can ensure that the set dose is greater than or equal to the remaining drug dose that can be injected, so that the actual injection dose is consistent with the set dose. The present application provides an injection device.

[0071] Refer to Figure 1 , the injection device includes a housing 7, a clutch element 4, the dose accumulation mechanism described above, a drive rod 5, and a push rod 6. Among them, the clutch element 4, the dose accumulation mechanism, the drive rod 5, and the push rod 6 are all arranged in the housing 7. And, during dose setting, at least one of the drive worm 1 and the mating member 2 can rotate relative to the clutch element 4; during dose injection, the clutch element 4 is anti-rotationally connected to the drive worm 1 and the mating member 2 in the dose injection direction. The drive worm 1, the mating member 2, the drive rod 5, and the push rod 6 are sleeved from the outside to the inside in this order. At the same time, the drive rod 5 is axially fixed and rotatably arranged in the housing 7, and the drive rod 5 is anti-rotationally connected to the mating member 2, while the push rod 6 is threadedly connected to the drive rod 5 and forms an axial guiding fit with the housing 7. Thus, during dose injection, the drive worm 1 drives the mating member 2 and the drive rod 5 to rotate in the dose injection direction, and thereby drives the push rod 6 to feed axially. Correspondingly, a cartridge 8 containing the drug is connected to the distal end of the injection device. A movable piston 81 is provided at the proximal end of the cartridge 8, and a needle assembly is connected to the distal end. The axially feeding push rod 6 is used to push the movable piston 81 of the cartridge 8 to move distally, so as to discharge the drug in the cartridge 8 through the needle assembly.

[0072] Specifically, refer to Figure 1 、 Figures 14 - 17, the proximal end of the cooperating member 2 is received in the proximal end of the driving worm 1. At the same time, the clutch element 4 is located at the proximal end portion of the driving worm 1 and presses against the proximal end portion of the cooperating member 2. At the same time, when adjusting to a larger dose, the driving worm 1 rotates in the third direction, and when adjusting to a smaller dose, the driving worm 1 rotates in the fourth direction opposite to the third direction. When injecting the dose, both the driving worm 1 and the cooperating member 2 rotate in the fourth direction. Specifically, the third direction is the clockwise direction, and the fourth direction is the counterclockwise direction. At the same time, the injection device further includes a button 9 and a spring 10, wherein the button 9 and the proximal end of the driving worm 1 form an anti-disengagement structure, and the spring 10 is located between the button 9 and the clutch element 4, and the spring 10 is used to maintain the clutch element 4 pressing against the proximal end portion of the cooperating member 2.

[0073] Correspondingly, a ratchet tooth ring 12 is provided on the inner wall of the proximal end of the driving worm 1, and the clutch element 4 is provided with a ratchet arm 41 that cooperates with the ratchet tooth ring 12. The cooperation between the ratchet tooth ring 12 and the ratchet arm 41 constitutes a first connection, and the first connection allows the driving worm 1 to rotate relative to the clutch element 4 in the third direction and prevents the driving worm 1 from rotating relative to the clutch element 4 in the fourth direction.

[0074] An axially protruding axial tooth ring 22 is provided at the proximal end portion of the cooperating member 2, and the clutch element 4 is provided with a mating tooth 42 that meshes with the axial tooth ring 22. Under the action of the elastic force of the spring 10, the axial tooth ring 22 and the mating tooth 42 cooperate to form a second connection. The second connection prevents the clutch element 4 from rotating relative to the cooperating member 2 in the third direction and allows relative axial movement between the clutch element 4 and the cooperating member 2 so that the clutch element 4 rotates relative to the cooperating member 2 in the fourth direction. At the same time, during the dose injection, the clutch element 4 is pressed against the proximal end of the cooperating member 2 under the action of the axial force transmitted by the button 9. At this time, no axial movement can occur between the clutch element 4 and the cooperating member 2, making the clutch element 4 and the cooperating member 2 relatively stationary.

[0075] Refer to Figure 17 , it should be noted that the axial tooth ring 22 and the mating tooth 42 are provided as inclined teeth with a cross-section similar to a right triangle. The inclined teeth have a right-angle surface 421 and an inclined surface 422. During the dose setting, when the right-angle surface 421 of the inclined tooth on the axial tooth ring 22 abuts against the right-angle surface 421 of the mating tooth 42, it prevents the clutch element 4 from rotating relative to the cooperating member 2 in the third direction. When the inclined surface 422 of the inclined tooth on the axial tooth ring 22 abuts against the inclined surface 422 of the mating tooth 42, relative axial movement occurs between the clutch element 4 and the cooperating member 2 and "tooth skipping" occurs under the action of the elastic force of the spring 10, that is, the tooth jumps from one groove to an adjacent groove.

[0076] In summary, when the driving worm 1 rotates in the third direction to increase the dosage, the clutch element 4 and the mating component 2 remain stationary. At this time, the driving worm 1 rotates relative to the mating component 2 and the clutch element 4. When the driving worm 1 rotates in the fourth direction to decrease the dosage, the driving worm 1 drives the clutch element 4 to rotate in the fourth direction, and the mating component 2 remains stationary. At this time, the driving worm 1 and the clutch element 4 rotate relative to the mating component 2. During the dosage injection, the driving worm 1, the clutch element 4, and the mating component 2 rotate synchronously in the fourth direction.

[0077] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0078] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A dose accumulation mechanism, characterized in that, Comprising: A driving worm which can rotate around a first axis, and the driving worm is provided with driving ribs; A mating member which is sleeved on the driving worm and can rotate around the first axis; An integrating worm wheel which is connected to the mating member and can rotate relative to the mating member around a second axis, the second axis is arranged intersecting with the first axis, the integrating worm wheel is provided with a plurality of meshing grooves, and the plurality of meshing grooves are arranged at intervals along the circumferential direction of the second axis, and the meshing grooves are used for the driving ribs to engage; A first limiting portion which is arranged on the driving worm or the mating member; A second limiting portion which is arranged on the integrating worm wheel; Wherein, during dose setting, the driving worm can rotate relative to the mating member in a first direction to increase the dose and rotate in a second direction to decrease the dose, and the driving ribs are used to drive the integrating worm wheel to rotate; during dose injection, the driving worm and the mating member are anti-rotationally connected; when the first limiting portion abuts against the second limiting portion, it constitutes the end position of the integrating worm wheel, and when the integrating worm wheel is in the end position, it prevents the driving worm from continuing to move in the first direction relative to the mating member.

2. The dose accumulation mechanism according to claim 1, characterized in that, The first limiting portion is arranged on the driving worm, and the movement direction of the first limiting portion when increasing the dose is defined as the end approaching direction, and when the second limiting portion blocks the first limiting portion from continuing to move in the end approaching direction, it constitutes the end position of the integrating worm wheel.

3. The dose accumulation mechanism according to claim 2, characterized in that, The first limiting portion is configured as the end of the driving rib.

4. The dose accumulation mechanism according to claim 3, characterized in that, Inside the meshing groove provided with the second limiting portion.

5. The dose accumulation mechanism according to claim 3, characterized in that, The outer periphery of the integrating worm wheel includes a meshing arc section and a stop arc section, the meshing arc section is formed by the meshing grooves arranged at intervals, and the side wall of the stop arc section serves as the second limiting portion for the first limiting portion to abut against.

6. The dose accumulation mechanism according to claim 1, characterized in that, The first limiting portion is arranged on the driving worm, and the movement direction of the second limiting portion when increasing the dose is defined as the end approaching direction, and when the first limiting portion blocks the second limiting portion from continuing to move in the end approaching direction, it constitutes the end position of the integrating worm wheel.

7. The dose accumulation mechanism according to claim 6, characterized in that, The second limiting portion is configured as a stop bar extending radially along the integrating worm wheel, and the first limiting portion is configured as a terminal abutting portion on the side wall of the driving worm.

8. The dose accumulation mechanism according to claim 1, characterized in that, The first limiting portion is arranged on the mating member, the first limiting portion is provided with an opposite first stop surface and a second stop surface, when the first stop surface abuts against the second limiting portion, it constitutes the starting position of the integrating worm wheel, and when the second stop surface abuts against the second limiting portion, it constitutes the end position of the integrating worm wheel; wherein, when the integrating worm wheel is in the starting position, it prevents the driving worm from continuing to move in the second direction relative to the mating member.

9. The dose accumulation mechanism according to any one of claims 1 to 7, characterized in that, The driving worm is sleeved outside the mating member, the driving ribs are arranged on the inner side wall of the driving worm, and the integrating worm wheel is inside the driving worm.

10. The dose accumulation mechanism according to any one of claims 1 to 7, characterized in that, The mating member is sleeved outside the driving worm, the driving ribs are arranged on the outer side wall of the driving worm, and the integrating worm wheel is outside the driving worm.

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