Integral worm gear and dose accumulation mechanism

Abstract

The utility model relates to an integral worm gear and a dose accumulation mechanism. The integral worm gear comprises a worm gear body; the meshing section comprises a plurality of meshing grooves, the meshing grooves are distributed in the circumferential direction of the worm gear body at intervals, and the meshing grooves are used for allowing driving ribs of a driving worm to be meshed in; the non-meshing section and the meshing section form a complete circumference, the non-meshing section is provided with a first end portion and a second end portion which are opposite in the extending direction of the non-meshing section, the first end portion and the second end portion are each provided with a stop portion, and the stop portion of the first end portion is used for allowing one end portion of the driving rib to abut against to form a starting position of the integral worm gear; and the stop part of the second end part is used for abutting against the other end part of the driving rib to form a stop position of the integral worm gear. The integral worm gear and the driving worm can form a starting position and a stopping position for limiting the total rotation amount of the integral worm gear, and therefore it is conveniently guaranteed that the set dosage accumulated by the integral worm gear is not larger than the total amount of medicine contained in the cartridge bottle.

Description

Technical Field

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

[0002] When injecting drugs, a specific injection device is used. This injection device is usually called a pen injector or injection pen. The user can adjust the dose based on needs and inject the adjusted dose; at the same time, the process of adjusting the dose and then injecting the adjusted dose is regarded as a complete injection.

[0003] During actual use, the injection device is paired with a cartridge containing medication. As the user injects each injection, the remaining dose of the medication in the cartridge gradually decreases. As the remaining dose in the cartridge continues to decrease, the dose set by the user based on demand may be greater than the remaining dose of the medication. Therefore, it is necessary to configure an integral structure for accumulating the dose setting value of the injection device. Utility Model Content

[0004] On the one hand, in order to accumulate the dose setting value of the injection device, the present application provides an integrating worm gear, which can accumulate the dose setting value of the injection device by rotating, and form a starting position and an end position with the driving worm to limit the total amount of rotation to limit the total amount of dose setting that can be accumulated.

[0005] The present application provides an integral worm gear adopting the following technical solution:

[0006] The worm gear of claim 1, wherein the worm gear has a first end and a second end that are opposite to each other in their extension direction, the first end and the second end being provided with a stop portion, the stop portion of the first end being used for allowing one end of the driving rib to abut against each other to form a starting position of the integral worm gear, and the stop portion of the second end being used for allowing the other end of the driving rib to abut against each other to form a termination position of the integral worm gear.

[0007] By adopting the above technical solution, during dose setting, the meshing groove in the meshing section cooperates with the drive rib of the drive worm, so that the drive worm can drive the integrating worm wheel to rotate, and the rotation of the integrating worm wheel accumulates the dose setting value of the injection device. When the end of the drive rib on the drive worm abuts the stop portion, further rotation between the drive worm and the integrating worm wheel is prevented. Specifically, one end of the drive rib abuts the stop portion at the first end of the non-meshing section to form a starting position, and the other end of the drive rib abuts the stop portion at the second end of the non-meshing section to form a stopping position. Under the cooperation of the drive worm, the integrating worm wheel is limited to rotation only between the starting position and the stopping position. The total amount of rotation of the integrating worm wheel between the starting position and the stopping position represents the cumulative total of the set doses of the injection device, thereby facilitating to ensure that the set dose accumulated by the integrating worm wheel is no greater than the total amount of drug contained in the cartridge.

[0008] Furthermore, the meshing section and the non-meshing section are both provided with meshing teeth arranged along the circumferential direction, the meshing groove is formed between two adjacent meshing teeth in the meshing section, and a closing block is provided between two adjacent meshing teeth in the non-meshing section, and the closing blocks at the first end and the second end serve as the stop portion.

[0009] Furthermore, the meshing section is provided with meshing teeth arranged along the circumferential direction, and the meshing groove is formed between two adjacent meshing teeth; the non-meshing section is provided with an arc-shaped baffle extending from the first end to the second end, and the part of the arc-shaped baffle at the first end and the second end serves as the stop portion.

[0010] Further, the non-engaging section includes a vacant section, and the vacant section is located between the first end and the second end.

[0011] Secondly, the present application provides a dose accumulation mechanism, in which an integrating worm gear can form a starting position and an ending position with a driving worm to limit the total amount of rotation of the integrating worm gear, and the total amount of rotation of the integrating worm gear represents the cumulative sum of the set doses of the injection device, thereby facilitating the guarantee that the set dose accumulated by the integrating worm gear is no greater than the total amount of the drug contained in the cartridge bottle.

[0012] The dose accumulation mechanism provided in this application adopts the following technical solution:

[0013] A dose accumulation mechanism, characterized in that it includes a driving worm and the above-mentioned integral worm wheel, wherein the driving worm can rotate around a first axis, and the integral worm wheel can rotate around a second axis perpendicular to the first axis, and the driving worm is provided with a driving rib, and the driving rib is used to cooperate with the engaging groove to drive the integral worm wheel to rotate.

[0014] By adopting the above technical solution, the integrating worm gear can form a starting position and an ending position with the driving worm to limit the total amount of rotation of the integrating worm gear. The total amount of rotation of the integrating worm gear represents the cumulative total of the set doses of the injection device, thereby facilitating the guarantee that the set dose accumulated by the integrating worm gear is no greater than the total amount of drug contained in the cartridge.

[0015] Furthermore, the driving rib has a first end and a second end opposite to each other along its extension direction, and a surrounding angle formed by the first end and the second end based on the first axis is less than 360°.

[0016] Furthermore, the driving rib includes a driving section and an engaging section at the end of the driving section. The process from the engagement section starting to engage into the engaging groove to the driving section starting to engage into the engaging groove is defined as the engagement process, and the process from the driving section completely disengaging from the engaging groove to the engagement section completely disengaging from the engaging groove is defined as the disengagement process. During the engagement process and the disengagement process, the integral worm gear and the mating component remain relatively stationary.

[0017] Furthermore, the dose adjusted by the driving worm rotating one circle around the first axis is defined as X, and the total set dose that can be accumulated by the dose accumulation mechanism is defined as Y, where Y is configured as an integer multiple of X.

[0018] Furthermore, the integral worm gear is arranged in the driving worm, and the driving rib is arranged on the inner side wall of the driving worm.

[0019] Furthermore, the integral worm gear is arranged outside the driving worm, and the driving rib is arranged on the outer side wall of the driving worm.

[0020] In summary, the present application includes the following beneficial technical effects: during dose setting, the meshing groove in the meshing section cooperates with the driving rib of the driving worm, so that the driving worm can drive the integrating worm wheel to rotate, and the dose setting value of the injection device is accumulated through the rotation of the integrating worm wheel; when the end of the driving rib on the driving worm abuts against the stop portion, further rotation between the driving worm and the integrating worm wheel is prevented, one end of the driving rib abuts against the stop portion at the first end of the non-meshing section to form a starting position, and the other end of the driving rib abuts against the stop portion at the second end of the non-meshing section to form a stopping position. Under the cooperation of the driving worm, the integrating worm wheel is limited to rotating only between the starting position and the stopping position; and the total amount of rotation of the integrating worm wheel between the starting position and the stopping position represents the cumulative total of the set doses of the injection device, thereby facilitating to ensure that the set dose accumulated by the integrating worm wheel is no greater than the total amount of medicine contained in the cartridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of an injection device with a dose accumulation mechanism in an embodiment of the present application. Figure 1 ;

[0022] Figure 2 This is a schematic diagram of an injection device with a dose accumulation mechanism in an embodiment of the present application. Figure 2 ;

[0023] Figure 3 This is a schematic diagram used to illustrate the driving rib and the stopper forming a starting position in an embodiment of the present application;

[0024] Figure 4 This is a schematic diagram used to illustrate the end position formed by the driving rib and the stop portion in the embodiment of the present application;

[0025] Figure 5 This is a schematic diagram for showing the integral worm gear in the embodiment of this application. Figure 1 ;

[0026] Figure 6 This is a schematic diagram for showing the integral worm gear in the embodiment of this application. Figure 2 ;

[0027] Figure 7 This is a schematic diagram for showing the integral worm gear in the embodiment of this application. Figure 3 ;

[0028] Figure 8 This is a schematic diagram for showing the integral worm gear in the embodiment of this application. Figure 4 ;

[0029] Figure 9 This is a schematic diagram for showing the integral worm gear in the embodiment of this application. Figure 5 ;

[0030] Figure 10 This is a schematic diagram of the matching relationship between the integral worm gear and the matching components in the embodiment of the present application. Figure 1 ;

[0031] Figure 11 Schematic diagram of the matching relationship between the integral worm gear and the driving worm in the embodiment of the present application;

[0032] Figure 12 This is a schematic diagram of the matching relationship between the integral worm gear and the matching components in the embodiment of the present application. Figure 2 ;

[0033] Figure 13 This is a schematic diagram of an embodiment of the present application in which a portion of the side wall of the rod body is hidden to reveal the driving ribs;

[0034] Figure 14 This is a schematic diagram for showing the driving ribs in the embodiment of this application. Figure 1 ;

[0035] Figure 15 This is a schematic diagram for showing the driving ribs in the embodiment of this application. Figure 2 ;

[0036] Figure 16 is a schematic diagram for illustrating a reference angle of an integrating worm gear in an embodiment of the present application;

[0037] Figure 17 is a cross-sectional view for illustrating the dose accumulation mechanism and the clutch element in an embodiment of the present application;

[0038] Figure 18 is a schematic diagram for illustrating the axial gear ring on the mating component in an embodiment of the present application;

[0039] Figure 19 This is an exploded schematic diagram for illustrating the dose accumulation mechanism and the clutch element in the embodiment of the present application;

[0040] Figure 20 It is a schematic diagram used to illustrate the mating teeth on the clutch element in the embodiment of the present application.

[0041] Description of reference numerals:

[0042] 1. Driving worm; 11. Driving rib; 111. Driving section; 112. Engaging section; 1121. First side wall; 1122. Second side wall; 12. Rod body; 13. Ratchet gear ring; 2. Mating component; 21. Radial through groove; 22. Support seat; 23. Axial gear ring; 3. Integral worm gear; 31. Engaging teeth; 32. Engaging groove; 33. Rotating shaft; 34. Worm gear body; 35. Closing block; 36. Arc-shaped stop bar; 37. Stop block; 38. Vacant section; 39. Stop part; 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 DESCRIPTION

[0043] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0044] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0045] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0046] A dose accumulation mechanism for cumulatively setting doses, based on the transmission principle of a worm gear, is currently being proposed. The mechanism comprises a drive worm, a mating component, and an integrating worm gear. The drive worm and mating component are rotatable relative to each other during dose setting, while forming a rotationally fixed coupling with the mating component during dose injection, allowing them to rotate synchronously. Furthermore, the integrating worm gear is rotatably connected to the mating component, with its meshing grooves meshing with the drive ribs of the drive worm.

[0047] In the above-described concept, during dose adjustment, the drive ribs on the drive worm drive the integrating worm gear to rotate relative to the mating component. During dose injection, the drive worm, mating component, and integrating worm gear remain relatively stationary, thereby accumulating the total dose set by the user through rotation of the integrating worm gear. Conventional worm gear transmissions do not include a limiter mechanism. To ensure that the accumulated set dose does not exceed the total amount of medication contained in the cartridge, the integrating worm gear and the drive worm must form a starting position and an ending position that prevent further rotation of the integrating worm gear, thereby limiting the total amount of rotation of the integrating worm gear. This requires improvements to the structure of the integrating worm gear.

[0048] The embodiment of the present application discloses a dose accumulation mechanism, wherein the integral worm gear 3 can form a starting position and an ending position with the driving worm 1 to limit the total amount of rotation of the integral worm gear 3 .

[0049] Reference Figure 1 and Figure 2 The dose accumulation mechanism includes a driving worm 1, a matching component 2 and an integral worm gear 3.

[0050] The driving worm 1 is capable of rotating about a first axis, which is the central axis of the housing 7. The driving worm 1 includes a rod body 12 and a driving rib 11 provided on the rod body 12. The driving rib 11 extends on the rod body 12 around the first axis. The mating component 2 is sleeved with the driving worm 1 and the mating component 2 is capable of rotating about the first axis. The integral worm wheel 3 is connected to the mating component 2 and is capable of rotating about a second axis relative to the mating component 2. The second axis is the central axis of the integral worm wheel 3 and is arranged intersectingly with the first axis. At the same time, the integral worm wheel 3 includes a worm wheel body 34, a meshing section, and a non-meshing section. The meshing section and the non-meshing section are both located on the outer periphery of the worm wheel body 34 and extend in the circumferential direction. The non-meshing section and the meshing section form a complete circumference that surrounds the worm wheel body 34.

[0051] Specifically, refer to Figures 3 to 9 The meshing section includes a plurality of meshing grooves 32, which are arranged at intervals along the circumferential direction of the worm wheel body 34, and the meshing grooves 32 are used for the driving rib 11 of the driving worm 1 to engage; the non-meshing section has a first end and a second end opposite to each other along its extension direction, and the first end and the second end are both provided with a stop portion 39; wherein the stop portion 39 at the first end is used for one end of the driving rib 11 to abut against each other to form the starting position of the integral worm wheel 3, and the stop portion 39 at the second end is used for the other end of the driving rib 11 to abut against each other to form the ending position of the integral worm wheel 3.

[0052] Simultaneously, during dose setting, the drive worm 1 and the mating component 2 are capable of rotating relative to each other, and dose setting includes both increasing and decreasing the dose. Accordingly, rotation of the drive worm 1 relative to the mating component 2 in a first direction is used to increase the dose, and rotation of the drive worm 1 relative to the mating component 2 in a second direction is used to decrease the dose, the first direction being opposite to the second direction. Simultaneously, throughout the dose setting period, the drive rib 11 is configured to engage with the engagement groove 32 to drive the integral worm gear 3 to rotate. During dose injection, the drive worm 1 and the mating component 2 are non-rotationally coupled, enabling synchronous rotation or stationary motion of the drive worm 1 and the mating component 2, during which the integral worm gear 3 remains stationary relative to the drive worm 1 and the mating component 2. In addition, one end of the driving rib 11 abuts against the stop portion 39 at the first end of the non-meshing section to form a starting position, and the other end of the driving rib 11 abuts against the stop portion 39 at the second end of the non-meshing section to form a stopping position. In cooperation with the driving worm 1, the integrating worm gear 3 is restricted to rotating only between the starting position and the stopping position; and the total amount of rotation of the integrating worm gear 3 between the starting position and the stopping position represents the cumulative total of the set doses of the injection device, thereby facilitating the guarantee that the set dose accumulated by the integrating worm gear 3 is no greater than the total amount of drug contained in the cartridge 8.

[0053] It should be noted that the intersecting arrangement of the first and second axes indicates that they are not parallel, that is, they are not in the same plane. Specifically, if the plane in which the first axis lies is defined as the first plane, then the second axis intersects the first plane at a point. In a specific embodiment, the first axis is configured to be perpendicular to the second axis to achieve better transmission efficiency in the transmission of driving force between the drive worm 1 and the integrating worm gear 3.

[0054] It should be noted that the aforementioned meshing section refers to the area that can form a meshing relationship with the driving rib 11, and the aforementioned non-meshing section refers to the area that cannot form a meshing relationship with the driving rib 11. It can be understood that the non-meshing section may include a stop section that prevents the movement of the driving rib 11, and may also include a vacant section 38 for avoiding the driving rib 11.

[0055] Reference Figure 5 and Figure 6In some specific embodiments, both the meshing section and the non-meshing section are provided with meshing teeth 31 arranged along the circumferential direction, an meshing groove 32 is formed between two adjacent meshing teeth 31 in the meshing section, and a closing block 35 is provided between two adjacent meshing teeth 31 in the non-meshing section. The setting of the closing block 35 makes the entire non-meshing section configured as a stop section that prevents the movement of the driving rib 11, and the closing block 35 at the first end serves as a stop portion 39 for one end of the driving rib 11 to abut against, and the closing block 35 at the second end serves as a stop portion 39 for the other end of the driving rib 11 to abut against. In some embodiments, the non-meshing section is provided with a plurality of closing blocks 35, and the closing blocks 35 at the first end and the second end are used for the ends of the driving rib 11 to abut against each other; in other specific embodiments, the non-meshing section is provided with only one closing block 35, and the closing block 35 belongs to both the first end and the second end, and one side wall of the closing block 35 is used for one end of the driving rib 11 to abut against each other, and the other side wall is used for the other end of the driving rib 11 to abut against each other.

[0056] Reference Figure 7 and Figure 8 In other specific embodiments, the meshing section is provided with meshing teeth 31 arranged in the circumferential direction, and an meshing groove 32 is formed between two adjacent meshing teeth 31. The non-meshing section is provided with an arc-shaped baffle 36 extending from the first end to the second end. The part of the arc-shaped baffle 36 at the first end serves as a stopper 39 for one end of the driving rib 11 to abut against, and the part of the arc-shaped baffle 36 at the second end serves as a stopper 39 for the other end of the driving rib 11 to abut against.

[0057] Reference Figure 9 In other specific embodiments, the non-meshing section is provided with a stop block 37 as a stop portion 39 at the first end and a stop block 37 as a stop portion 39 at the second end, and there is a vacant section 38 between the first end and the second end for avoiding the driving rib 11.

[0058] It can be understood that the mating component 2 and the driving worm 1 are sleeved together in such a way that the driving worm 1 is sleeved outside the mating component 2 , or the mating component 2 is sleeved outside the driving worm 1 .

[0059] Reference Figure 1 and Figure 10In some embodiments, the driving worm 1 is sleeved on the outside of the mating component 2. The driving worm 1 is generally cylindrical, and the driving rib 11 is disposed on the inner sidewall of the rod body 12. The mating component 2 is generally cylindrical and at least partially accommodated within the driving worm 1. The integrating worm gear 3 is completely accommodated within the driving worm 1. The integrating worm gear 3 is rotationally connected to the mating component 2 via a rotating shaft 33. Accordingly, the mating component 2 is provided with a clearance zone that allows the integrating worm gear 3 to rotate unrestricted. In some specific embodiments, the mating component 2 is provided with a radial groove 21 perpendicular to the first and second axes. The integrating worm gear 3 is mounted in the radial groove 21, and the radial groove 21 serves as a clearance zone on the mating component 2 that allows the integrating worm gear 3 to rotate freely. Furthermore, the meshing section of the integrating worm gear 3 mounted in the radial groove 21, which includes an engagement groove 32, can protrude from a notch in the radial groove 21 and mesh with the driving rib 11 on the inner sidewall of the driving worm 1.

[0060] In the above embodiment, during dose setting, the drive worm 1 rotates about a first axis while the mating component 2 remains stationary. During dose injection, the drive worm 1 rotates synchronously with the mating component 2. It will be understood that if the drive worm 1 is defined as rotating clockwise when increasing the dose and counterclockwise when decreasing the dose, then rotation of the drive worm 1 relative to the mating component 2 in a first direction corresponds to clockwise rotation of the mating component 2 when the mating component 2 is stationary, and rotation of the drive worm 1 relative to the mating component 2 in a second direction corresponds to counterclockwise rotation of the mating component 2 when the mating component 2 is stationary. Furthermore, the first direction is the same as the clockwise rotation direction, and the second direction is the same as the counterclockwise rotation direction.

[0061] Reference Figure 2 、 Figure 11 and Figure 12 In other embodiments, the mating component 2 is sleeved on the outside of the driving worm 1. The mating component 2 is roughly cylindrical, and the integral worm wheel 3 is completely accommodated in the mating component 2 and outside the driving worm 1. At the same time, a support seat 22 is provided on the inside of the mating component 2, and the integral worm wheel 3 is rotatably mounted on the support seat 22 of the mating component 2; the driving worm 1 is at least partially accommodated in the mating component 2, and the driving rib 11 is arranged on the outer wall of the driving worm 1. Accordingly, a movable cavity for the free rotation of the integral worm wheel 3 is formed between the driving worm 1 and the mating component 2; in some specific embodiments, there is a gap between the inner wall of the mating component 2 and the outer wall of the driving worm 1 on which the driving rib 11 is provided, so that an annular cavity is formed between the driving worm 1 and the mating component 2, and the annular cavity serves as a movable cavity for the free rotation of the integral worm wheel 3.

[0062] In the above embodiment, during dose setting, the mating component 2 rotates about the first axis while the drive worm 1 remains stationary. During dose injection, the mating component 2 and the drive worm 1 rotate synchronously. If the mating component 2 is defined as rotating clockwise when adjusting the dose up and counterclockwise when adjusting the dose down, it can be understood that rotation of the drive worm 1 relative to the mating component 2 in the dose-increasing direction corresponds to the drive worm 1 being stationary while the mating component 2 rotates clockwise, and rotation of the drive worm 1 relative to the mating component 2 in the second direction corresponds to the drive worm 1 being stationary while the mating component 2 rotates counterclockwise, with the first direction being the same as the counterclockwise direction and the second direction being the same as the clockwise direction.

[0063] It should be noted that the driving rib 11 extending around the first axis on the rod body 12 means that the driving rib 11 is provided on the driving worm 1 and extends in a spiral manner along the axial direction thereof with the first axis as the spiral axis; accordingly, for the convenience of description, the two opposite ends of the driving rib 11 along its extension direction are defined as the first end and the second end, and the first end and the second end have an axial spacing in the direction of the first axis. At the same time, combined with Figure 13 , the number of turns of the driving rib 11 around the driving worm 1 is less than one, that is, the angle formed by the first and second ends about the first axis is less than 360°. It can be understood that this ensures that the axial projection of the driving rib 11 along the first axis does not have any overlapping areas, that is, the axial projection appears as an arc with a notch. Therefore, when the driving worm 1 and the driving rib 11 thereon are prepared by injection molding, axially opposed mold cores can be used to form the axially opposed side walls of the driving rib 11. After injection molding, the mold can be easily demolded by simply axially withdrawing the axially opposed mold cores.

[0064] Further, refer to Figures 13 to 15 In some specific embodiments, the driving rib 11 includes a driving section 111 and two engaging sections 112 at the ends of the driving section 111, that is, the driving rib 11 includes the engaging section 112, the driving section 111 and the engaging section 112 connected in sequence along its extension direction; wherein, the engaging section 112 is the part of the driving rib 11 that first engages with the engaging groove 32 on the integral worm gear 3, or the last to disengage from the engaging groove 32 on the integral worm gear 3, and the driving section 111 is the part of the driving rib 11 used to drive the integral worm gear 3 to rotate.

[0065] Similarly, for the convenience of subsequent description, the process from the engagement section 112 starting to engage into the engagement groove 32 to the drive section 111 starting to engage into the engagement groove 32 is defined as the engagement process, the process from the drive section 111 starting to engage into the engagement groove 32 to the drive section 111 completely disengaging from the engagement groove 32 is defined as the driving process, and the process from the drive section 111 completely disengaging from the engagement groove 32 to the engagement section 112 completely disengaging from the engagement groove 32 is defined as the disengagement process; accordingly, the integral worm gear 3 and the mating component 2 remain relatively stationary during the engagement process and the disengagement process.

[0066] If the driving rib 11 does not spiral more than once, there is a possibility that the driving rib 11 will completely disengage from the meshing groove 32 on the integral worm gear 3, that is, the first end may disengage from the meshing groove 32 while the second end has not yet engaged with another meshing groove 32. In this case, the integral worm gear 3 remains stationary. If the driving rib 11 is configured as a continuous spiral segment, the end of the driving rib 11 may not be fully aligned with the meshing groove 32 when it reengages the integral worm gear 3. This may cause the integral worm gear 3 to rotate excessively, thereby resulting in cumulative errors in the integral worm gear 3. By adopting the above solution, the driving rib 11 can only drive the integral worm gear 3 to rotate during the driving process of the driving segment 111, while the integral worm gear 3 remains stationary during the engagement and disengagement processes of the engagement segment 112. This ensures that the end of the driving rib 11 remains aligned with the meshing groove 32 when it reengages the integral worm gear 3, thereby avoiding the situation in which the integral worm gear 3 rotates excessively and thus resulting in cumulative errors in the integral worm gear 3.

[0067] Further, refer to Figure 14 and Figure 15 In some embodiments where the driving rib 11 includes a driving segment 111 and an engaging segment 112, the central extension axis of the engaging segment 112 is configured as an arc circumferentially disposed about the first axis. For ease of description, the opposing sidewalls of the engaging segment 112 along the first axial direction are defined as a first sidewall 1121 and a second sidewall 1122, respectively. The direction of the engaging segment 112 away from the driving segment 111 is defined as a moving away direction.

[0068] Reference Figure 14 In some specific embodiments, the axial distance between the first side wall 1121 and the second side wall 1122 remains unchanged along the moving away direction, that is, the engaging section 112 is configured as a circular arc segment. It should be noted that the driving rib 11 includes two engaging sections 112, both of which are circular arc segments, but the two engaging sections 112 are located at different axial positions on the first axis. Figure 15 In some other specific embodiments, the axial distance between the first side wall 1121 and the second side wall 1122 gradually decreases along the away direction, that is, the engaging section 112 is configured as a tapered section with a gradually decreasing width.

[0069] Furthermore, in other embodiments where the driving rib 11 includes a driving section 111 and an engaging section 112, the driving section 111 is configured as a spiral section spirally arranged around a first axis; the spiral section is used to engage with the engaging groove 32, and is used to drive the integral worm gear 3 to rotate when the spiral section rotates synchronously with the driving worm 1.

[0070] Furthermore, in some embodiments, the dose adjusted by the drive worm 1 rotating one circle around the first axis is defined as X, and the total set dose that can be accumulated by the dose accumulation mechanism is defined as Y, then Y is configured as an integer multiple of X, that is, when the maximum set dose is reached, the drive worm 1 has accumulated an integer number of rotations relative to the mating component 2 in the direction of increasing the dose.

[0071] Further, refer to Figure 3 and 16 In some embodiments, when the driving worm 1 rotates one circle relative to the mating component 2, the integral worm wheel 3 is driven to rotate one tooth angle; specifically, the central angle formed by the center points of two adjacent meshing grooves 32 on the integral worm wheel 3 relative to the second axis is defined as the reference angle a. When the driving worm 1 and the mating component 2 rotate one circle relative to each other, that is, 360°, the rotation angle of the integral worm wheel 3 is a reference angle a.

[0072] The embodiment of the present application further discloses an injection device that can ensure that the set dose does not exceed the remaining dose of the drug that can be injected, so that the actual injection dose is consistent with the set dose.

[0073] Reference Figure 1 The injection device includes a housing 7, a clutch element 4, the aforementioned dose accumulation mechanism, a drive rod 5, and a push rod 6. The clutch element 4, dose accumulation mechanism, drive rod 5, and push rod 6 are all disposed within the housing 7. Furthermore, during dose setting, at least one of the drive worm 1 and the mating component 2 is capable of relative rotation with the clutch element 4. During dose injection, the clutch element 4 is non-rotatably coupled to the drive worm 1 and the mating component 2 in the dose injection direction. The drive worm 1, the mating component 2, the drive rod 5, and the push rod 6 are sleeved together from the outside inward. The drive rod 5 is axially fixed and rotatably disposed within the housing 7 and non-rotatably coupled to the mating component 2. The push rod 6 is threadedly coupled to the drive rod 5 and forms an axially guided engagement with the housing 7. Therefore, during dose injection, the drive worm 1 drives the mating component 2 and the drive rod 5 to rotate in the dose injection direction, thereby driving the push rod 6 axially. Accordingly, the distal end of the injection device is connected to a cartridge 8 containing a drug, 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 fed push rod 6 is used to push the movable piston 81 of the cartridge 8 toward the distal end, thereby expelling the drug in the cartridge 8 through the needle assembly.

[0074] Specifically, refer to Figures 17 to 20The proximal end of the mating component 2 is accommodated in the proximal end of the drive worm 1. At the same time, the clutch element 4 is located at the proximal end of the drive worm 1 and presses against the proximal end of the mating component 2. At the same time, when the dose is increased, the drive worm 1 rotates in a third direction. When the dose is decreased, the drive worm 1 rotates in a fourth direction opposite to the third direction. When the dose is injected, both the drive worm 1 and the mating component 2 rotate in the fourth direction. Specifically, the third direction is clockwise, and the fourth direction is counterclockwise. At the same time, the injection device also includes a button 9 and a spring 10, wherein the button 9 and the proximal end of the drive worm 1 form an anti-slip structure, 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 pressed against the proximal end of the mating component 2.

[0075] Correspondingly, a ratchet tooth ring 13 is provided on the inner wall of the proximal end of the driving worm 1, and a ratchet arm 41 is provided which cooperates with the ratchet tooth ring 13. The ratchet tooth ring 13 and the ratchet arm 41 cooperate to form a first connection, which allows the driving worm 1 to rotate in a third direction relative to the clutch element 4, while preventing the driving worm 1 from rotating in a fourth direction relative to the clutch element 4.

[0076] The proximal end of the mating component 2 is provided with an axially protruding axial toothed ring 23, and the clutch element 4 is provided with mating teeth 42 that mesh with the axial toothed ring 23. Under the elastic force of the spring 10, the axial toothed ring 23 cooperates with the mating teeth 42 to form a second connection. This second connection prevents the clutch element 4 from rotating in the third direction relative to the mating component 2, while allowing relative axial movement between the clutch element 4 and the mating component 2, thereby rotating in the fourth direction relative to the mating component 2. Simultaneously, during dose injection, the clutch element 4 is pressed against the proximal end of the mating component 2 by the axial force transmitted by the button 9. At this time, the clutch element 4 and the mating component 2 cannot undergo axial movement, and the clutch element 4 and the mating component 2 remain relatively stationary.

[0077] Combine Figure 20 It should be noted that the axial gear ring 23 and the mating teeth 42 are configured as inclined teeth with a cross-section similar to a right-angled triangle, and the inclined teeth have a right-angled surface 421 and an inclined surface 422. During dose setting, when the right-angled surface 421 of the inclined tooth on the axial gear ring 23 abuts against the right-angled surface 421 of the mating tooth 42, the clutch element 4 is prevented from rotating in the third direction relative to the mating component 2. When the inclined surface 422 of the inclined tooth on the axial gear ring 23 abuts against the inclined surface 422 of the mating tooth 42, the clutch element 4 and the mating component 2 experience relative axial movement and "tooth jumping" occurs under the action of the elastic force of the spring 10, that is, the tooth jumps from one groove to an adjacent groove.

[0078] In summary, when the drive worm 1 rotates in the third direction to increase the dose, the clutch element 4 and the mating component 2 remain stationary, and the drive worm 1 rotates relative to the mating component 2 and the clutch element 4. When the drive worm 1 rotates in the fourth direction to decrease the dose, the drive worm 1 drives the clutch element 4 to rotate in the fourth direction, and the mating component 2 remains stationary. At this time, the drive worm 1 and the clutch element 4 rotate relative to the mating component 2. During dose injection, the drive worm 1, the clutch element 4, and the mating component 2 rotate synchronously in the fourth direction.

[0079] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative use of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0080] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An integral worm gear, characterized in that: include: A worm gear body capable of rotating about its own axis; an engagement section located at the outer periphery of the worm gear body and extending in the circumferential direction, the engagement section including a plurality of engagement grooves spaced apart along the circumferential direction of the worm gear body, the engagement grooves being used for engagement with driving ribs of the driving worm; The non-meshing section is located at the outer periphery of the worm gear body and extends in the circumferential direction. The non-meshing section and the meshing section form a complete circumference. The non-meshing section has a first end and a second end opposite to each other along its extension direction. The first end and the second end are both provided with a stop portion. The stop portion of the first end is used for one end of the driving rib to abut against each other to form the starting position of the integral worm gear, and the stop portion of the second end is used for the other end of the driving rib to abut against each other to form the ending position of the integral worm gear.

2. The integral worm gear according to claim 1, characterized in that: The meshing section and the non-meshing section are both provided with meshing teeth arranged along the circumferential direction, the meshing groove is formed between two adjacent meshing teeth in the meshing section, and a closing block is provided between two adjacent meshing teeth in the non-meshing section, and the closing blocks at the first end and the second end serve as the stopper.

3. The integral worm gear according to claim 1, characterized in that: The meshing section is provided with meshing teeth arranged in the circumferential direction, and the meshing groove is formed between two adjacent meshing teeth; the non-meshing section is provided with an arc-shaped baffle extending from the first end to the second end, and the parts of the arc-shaped baffle at the first end and the second end serve as the stop portion.

4. The integral worm gear according to claim 1, characterized in that: The non-engaging section includes a void section between the first end and the second end.

5. A dose accumulation mechanism, characterized in that: It comprises a driving worm and an integral worm wheel according to any one of claims 1 to 4, wherein the driving worm is capable of rotating around a first axis, the integral worm wheel is capable of rotating around a second axis perpendicular to the first axis, and the driving worm is provided with a driving rib, which is used to cooperate with the engaging groove to drive the integral worm wheel to rotate.

6. The dose accumulation mechanism according to claim 5, characterized in that: The driving rib has a first end and a second end opposite to each other along its extending direction, and a surrounding angle formed by the first end and the second end based on the first axis is less than 360°.

7. The dose accumulation mechanism according to claim 6, characterized in that: The driving rib includes a driving section and an engaging section at the end of the driving section. The process from the engagement section starting to engage and enter the engaging groove to the driving section starting to engage and enter the engaging groove is defined as the engagement process, and the process from the driving section completely disengaging from the engaging groove to the engagement section completely disengaging from the engaging groove is defined as the disengagement process. The integral worm gear remains stationary during the engagement process and the disengagement process.

8. The dose accumulation mechanism according to claim 5, characterized in that: The dose adjusted by the driving worm rotating one circle around the first axis is defined as X, and the total set dose that can be accumulated by the dose accumulation mechanism is defined as Y, where Y is configured as an integer multiple of X.

9. The dose accumulation mechanism according to any one of claims 5 to 8, characterized in that: The integral worm wheel is arranged in the driving worm, and the driving rib is arranged on the inner side wall of the driving worm.

10. The dose accumulation mechanism according to any one of claims 5 to 8, characterized in that: The integral worm wheel is arranged outside the driving worm, and the driving rib is arranged on the outer side wall of the driving worm.

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