Injection device capable of limiting final dose setting

Abstract

The present application relates to an injection device capable of limiting a final dose setting, comprising: a housing; the scale element can rotate relative to the shell so as to set the dosage; the transmission element is arranged in the scale element in a penetrating manner; the accumulation element is provided with a second termination part and a plurality of meshing grooves; the clutch element is arranged between the scale element and the transmission element; wherein one of the scale element and the transmission element is provided with a first termination part and a driving rib capable of being engaged into the engagement groove, and the accumulation element is rotatably connected to the other one of the scale element and the transmission element; during dose setting, one of the scale element and the transmission element can rotate relative to the clutch element, and the other one is in anti-rotation connection with the clutch element; when the first termination portion abuts against the second termination portion, a termination position of the accumulation element is formed. It can be guaranteed that the set dosage is smaller than or equal to the residual medicine dosage capable of being injected, so that the actual injection dosage conforms to the set dosage, and the situation that the wrong dosage is injected is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of injection devices, and in particular to an injection device capable of limiting the final dose setting. 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 equipped with a cartridge containing the drug. As the user injects each time, the remaining dose of the drug 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 drug, which will cause the actual injection dose in the injection to be lower than the required injection dose, and may result in the wrong dose being injected. Summary of the invention

[0004] In order to ensure that the set dose is less than or equal to the remaining dose of the drug that can be injected, so that the actual injected dose is consistent with the set dose and to avoid the situation where the wrong dose is injected, the present application provides an injection device capable of limiting the final dose setting.

[0005] The present application provides an injection device capable of limiting the final dose setting, which adopts the following technical solution:

[0006] An injection device capable of limiting the final dose setting comprises: a housing having a first axis; a scale element capable of rotating relative to the housing around the first axis to set the dose; a transmission element inserted in the scale element and capable of rotating around the first axis; an accumulation element capable of rotating around a second axis, the second axis being arranged crosswise with the first axis, the accumulation element being provided with a second terminating portion and a plurality of meshing grooves, the plurality of meshing grooves being arranged at intervals along the circumferential direction of the second axis; a clutch element being provided between the scale element and the transmission element; wherein one of the scale element and the transmission element is provided with a first terminating portion and a driving element capable of meshing into the meshing groove. The driving rib is configured to be a driving rib, wherein the accumulation element is rotatably connected to the other of the scale element and the transmission element; during dose setting, one of the scale element and the transmission element can rotate relative to the clutch element, and the other is anti-rotationally connected to the clutch element; when the scale element and the transmission element rotate relative to each other, the driving rib drives the accumulation element to rotate, and when the first end portion abuts against the second end portion, a stop position of the accumulation element is formed, and when the accumulation element is in the stop position, the scale element is prevented from rotating relative to the transmission element in the direction of increasing the dose; during dose injection, the clutch element locks the scale element and the transmission element in the rotation direction.

[0007] By adopting the above technical solution, during the dose setting period, the scale element and the transmission element rotate relative to each other so that the accumulation element rotates along the second axis, and the rotation angle of the accumulation element corresponds to the dose setting amount achieved by the scale element, and during the dose injection period, the scale element, the transmission element and the accumulation element all remain relatively stationary; therefore, during a complete injection process, the accumulation element can record the dose setting amount by its own rotation, and accordingly, as the user performs successive injections, the accumulation element can accumulate and record the total amount of dose setting until the accumulation element moves to the end position where the first end portion and the second end portion abut against each other, and the accumulation element is restricted from further rotation. At this time, the scale element and the transmission element cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose, and further limiting the final dose setting of the injection device, and correspondingly setting the final dose setting value to be less than or equal to the total amount of the drug that can be injected by the injection device, so as to ensure that the set dose is less than or equal to the remaining drug dose that can be injected by the injection device, so that the actual injection dose is consistent with the set dose to avoid the situation of injecting the wrong dose.

[0008] Furthermore, the movement direction of the first terminating portion when increasing the dose is defined as a terminating approach direction, and the terminating position of the accumulating element is formed when the second terminating portion moves to block the first terminating portion from continuing to move along the terminating approach direction.

[0009] In actual use, the action of dose setting is reflected in the relative rotation between the scale element and the transmission element, and the relative rotation between the scale element and the transmission element is converted into the rotation of the accumulation element through the cooperation of the driving rib and the accumulation element, which is similar to the cooperation transmission structure of the worm thread and the worm gear tooth groove, and belongs to the deceleration motion. Therefore, the dose represented by the movement of the first end part by one unit angle will be smaller than the dose represented by the movement of the second end part by one unit angle, and the actual manufacturing inevitably has dimensional errors. In the above scheme, compared with limiting the movement of the second end part to limit the end position, limiting the end position by limiting the movement of the first end part can reduce the adverse effect of dimensional errors on dose accumulation.

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

[0011] Furthermore, the second terminating portion is disposed on the outer periphery of the accumulating element for the end of the driving rib to abut against.

[0012] Furthermore, a first starting portion is provided on the element equipped with the driving rib, and a second starting portion is provided on the accumulation element. The movement direction of the first starting portion when reducing the dose is defined as a starting approach direction. When the second starting portion moves to block the first starting portion from continuing to move along the starting approach direction, a starting position of the accumulation element is formed. When the accumulation element is in the starting position, the scale element is prevented from rotating relative to the transmission element in the direction of reducing the dose.

[0013] Furthermore, the driving rib is arranged on the outer side wall of the transmission element, and the accumulation element is rotatably connected to the scale element.

[0014] Furthermore, the transmission element includes a proximal element and a distal element distributed along the axial direction, the proximal element is used to extend into the scale element from the proximal end of the scale element, and the distal element is used to extend into the scale element from the distal end of the scale element, and the distal end of the proximal element is fixedly connected to the proximal end of the distal element.

[0015] Furthermore, the driving rib is arranged on the inner side wall of the scale element, and the accumulating element is rotatably connected to the transmission element.

[0016] Further, the driving rib extends on the scale element around the first axis, and 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 or equal to 360°.

[0017] By adopting the above technical scheme, the driving rib is surrounded by less than or equal to one circle, that is, there is no staggered overlapping area in the axial projection of the driving rib. Accordingly, when the driving component and the driving rib thereon are prepared by injection molding, axially opposed mold cores can be used to form the axially opposite side walls of the driving rib, and after injection molding, it is only necessary to axially pull the axially opposed mold cores apart for convenient demolding. Compared with allowing the driving rib to surround more than one circle and requiring spiral core pulling for demolding after injection molding, the scale element of this scheme can be more convenient in the manufacturing process.

[0018] Further, the driving rib includes a driving section and an engagement section at the end of the driving section, and the process from the engagement section starting to engage and enter the engagement groove to the driving section starting to engage and enter the engagement groove is defined as the engagement process, and the process from the driving section completely disengaging from the engagement groove to the engagement section completely disengaging from the engagement groove is defined as the disengagement process, and the accumulation element and the transmission element remain relatively stationary during the engagement process and the disengagement process.

[0019] Furthermore, a coupling structure is provided between the clutch element and the scale element, the coupling structure allows the scale element to rotate relative to the clutch element in a direction of increasing the dose, and prevents the scale element from rotating relative to the clutch element in a direction of decreasing the dose.

[0020] Further, the connecting structure includes a ratchet tooth ring arranged on the inner side of the scale element and a ratchet arm arranged on the outer side of the clutch element, the ratchet tooth ring having ratchet tooth grooves arranged in a circumferential direction, the ratchet arm including an arc-shaped elastic arm and a pawl at the free end of the arc-shaped elastic arm, the pawl being capable of being embedded in the ratchet tooth groove; the ratchet tooth groove has a first groove wall and a second groove wall opposite to each other in a circumferential direction, and the pawl has a first side wall and a second side wall opposite to each other in a circumferential direction; when the scale element rotates in a direction of increasing the dose relative to the clutch element, the first side wall abuts against the first groove wall and slides against each other as the two continue to approach each other; when the scale element rotates in a direction of decreasing the dose relative to the clutch element, the second side wall abuts against the second groove wall and prevents further approach.

[0021] Further, the transmission element is provided with a first engaging portion, and the clutch element is provided with a second engaging portion for engaging with the first engaging portion, and the clutch element can be axially moved from a first matching position to a second matching position relative to the transmission element, and when the clutch element is in the first matching position, the first engaging portion is engaged with the second engaging portion, and when the clutch element is in the second matching position, the first engaging portion is separated from the second engaging portion; during dose increase, the clutch element is in the first matching position to prevent the clutch element from rotating relative to the transmission element in the dose increase direction; during dose decrease, the clutch element can be moved from the first matching position to the second matching position to allow the clutch element to rotate relative to the transmission element in the dose decrease direction; during dose injection, the clutch element is prevented from moving from the first matching position to the second matching position to prevent the clutch element from rotating relative to the transmission element.

[0022] Furthermore, the injection device further comprises a pushing element and an elastic element, wherein the pushing element is located proximal to the clutch element, and the elastic element is located between the pushing element and the elastic element; the pushing element can move axially relative to the scale element and has a first position and a second position relative to the scale element, the pushing element is in the first position during dose setting, and the pushing element is moved from the first position to the second position by a thrust during dose injection, and the pushing element in the second position prevents the clutch element from moving from the first matching position to the second matching position; the elastic element provides elastic resistance for the clutch element to move from the first matching position to the second matching position, and the elastic element provides elastic resistance for the pushing element to move from the first matching position to the second matching position.

[0023] In summary, the present application includes the following beneficial technical effects: during a complete injection process, the accumulation element can record the dose setting amount by its own rotation, and accordingly, as the user performs successive injections, the accumulation element can accumulate and record the total amount of the dose setting until the accumulation element moves to the end position where the first end portion and the second end portion abut against each other, and the accumulation element is restricted from further rotation. At this time, the scale element and the transmission element cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose, and further limiting the final dose setting of the injection device, and accordingly setting the final dose setting value to be less than or equal to the total amount of the drug that can be injected by the injection device, thereby ensuring that the set dose is less than or equal to the remaining drug dose that can be injected by the injection device, so that the actual injection dose is consistent with the set dose to avoid the situation of injecting the wrong dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the injection device in the embodiment of the present application Figure 1 ;

[0025] Figure 2 is a schematic diagram of the injection device in the embodiment of the present application Figure 2 ;

[0026] Figure 3 It is a schematic diagram of hiding part of the side wall of the scale element in the embodiment of the present application to show the end position of the accumulation element;

[0027] Figure 4 It is a cross-sectional view for the scale element, the transmission element and the clutch mechanism in the embodiment of the present application;

[0028] Figure 5 It is an exploded schematic diagram for showing the scale element, the transmission element and the clutch mechanism in the embodiment of the present application;

[0029] Figure 6 It is a schematic diagram used to show the cumulative components in the embodiment of the present application. Figure 1 ;

[0030] Figure 7 It is a schematic diagram used to show the cumulative components in the embodiment of the present application. Figure 2 ;

[0031] Figure 8 is a schematic diagram of an embodiment of the present application in which a portion of the side wall of the scale element is hidden to show the starting position of the accumulation element;

[0032] Fig. 9 It is a schematic diagram used to show the accumulating element and the transmission element in the embodiment of the present application. Figure 1 ;

[0033] Fig.10 is a schematic diagram of an embodiment of the present application in which a portion of the side wall of the scale element is hidden to display the driving ribs;

[0034] Fig.11 is a schematic diagram for illustrating a reference angle of a cumulative element in an embodiment of the present application;

[0035] Fig.12 It is a schematic diagram used to show the accumulation element and the transmission element in the embodiment of the present application. Figure 2 ;

[0036] Fig.13 It is a schematic diagram for showing the accumulation element and the scale element in the embodiment of the present application;

[0037] Fig.14 It is a schematic diagram used to show the clutch element in the embodiment of the present application. Figure 1 ;

[0038] Fig.15 It is a schematic diagram used to show the clutch element in the embodiment of the present application. Figure 2 ;

[0039] Fig.16 It is a schematic diagram used to display the transmission elements in the embodiments of the present application.

[0040] Description of reference numerals:

[0041] 1. Shell; 2. Dose accumulation mechanism; 21. Scale element; 211. Support seat; 212. Ratchet tooth ring; 22. Transmission element; 221. Proximal element; 222. Distal element; 223. First meshing portion; 224. Radial through groove; 23. Accumulation element; 231. Meshing teeth; 232. Meshing groove; 233. Second starting portion; 234. Second ending portion; 24. Driving rib; 241. Driving section; 242. Engaging section; 243. First starting portion; 244. First terminating portion; 25. Stop arc segment; 3. Clutch mechanism; 31. Clutch element; 311. Ratchet arm; 312. Arc-shaped elastic arm; 313. Ratchet pawl; 3131. First side wall; 3132. Second side wall; 314. Second meshing portion; 3141. Right-angle surface; 3142. Inclined surface; 32. Pushing element; 33. Elastic element; 4. Transmission mechanism; 41. Drive rod; 42. Push rod; 5. Cartridge bottle; 51. Movable piston; 6. Needle assembly. DETAILED DESCRIPTION

[0042] Embodiments of the present invention are described in detail below, examples of which 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0043] 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 positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] The embodiment of the present application discloses an injection device capable of limiting the final dose setting.

[0046] Reference Figure 1 and Figure 2 The injection device capable of limiting the final dose setting includes a housing 1, a dose accumulation mechanism 2, a clutch mechanism 3 and a transmission mechanism 4, wherein the housing 1 is a cylindrical component having a first axis, and the dose accumulation mechanism 2, the clutch mechanism 3 and the transmission mechanism 4 are at least partially located in the housing 1.

[0047] Specifically, the dose accumulation mechanism 2 includes a scale element 21 , a transmission element 22 and an accumulation element 23 .

[0048] Among them, the scale element 21 can rotate around the first axis relative to the shell 1 to set the dose, and the transmission element 22 is inserted into the scale element 21, and the transmission element 22 can rotate around the first axis. At the same time, one of the transmission element 22 and the scale element 21 is provided with a driving rib 24, and accordingly, the accumulation element 23 is rotatably connected to the other of the transmission element 22 and the scale element 21 along the second axis, and the second axis is the central axis of the accumulation element 23, and the second axis is arranged crosswise with the first axis; the accumulation element 23 is provided with a plurality of meshing teeth 231, and the plurality of meshing teeth 231 are arranged at intervals along the circumferential direction of the second axis, so that a meshing groove 232 for the driving rib 24 to engage is formed between two adjacent meshing teeth 231. Therefore, when the transmission element 22 rotates relative to the scale element 21 in the dose increase direction and the dose decrease direction, the driving rib 24 can drive the accumulation element 23 to rotate around the second axis, so that the dose setting amount is recorded by the rotation amount of the accumulation element 23. In addition, combined with Figure 3 The component on which the driving rib 24 is provided is also provided with a first terminating portion 244, and the accumulating element 23 is provided with a second terminating portion 234 for the first terminating portion 244 to abut against. When the first terminating portion 244 abuts against the second terminating portion 234, the accumulating element 23 is formed at the terminating position, and when the accumulating element 23 is in the terminating position, the scale element 21 is prevented from rotating relative to the transmission element 22 in the direction of increasing the dose, that is, further increasing the dose is limited.

[0049] Accordingly, combined Figure 4 and Figure 5 The clutch mechanism 3 includes a clutch element 31 disposed between the scale element 21 and the transmission element 22; during dose setting, one of the scale element 21 and the transmission element 22 can rotate relative to the clutch element 31, so that the scale element 21 and the transmission element 22 rotate relative to each other during dose setting, and during dose injection, the clutch element 31 locks the scale element 21 and the transmission element 22 in the rotational direction.

[0050] In addition, refer to Figure 1 and Figure 2 The transmission mechanism 4 includes a driving rod 41 and a push rod 42. The driving rod 41 is located in the transmission element 22 and is sleeved outside the push rod 42. At the same time, the driving rod 41 is axially fixed and rotatably arranged in the housing 1, and the driving rod 41 is anti-rotationally connected to the transmission element 22, while the push rod 42 is threadedly connected to the driving rod 41 and forms an axial guiding match with the housing 1, so that during the dose injection, the scale element 21 drives the transmission element 22 and the driving rod 41 to rotate in the dose injection direction, and thereby drives the push rod 42 to feed axially. Correspondingly, the distal end of the injection device is connected to a cartridge 5 containing a drug, the proximal end of the cartridge 5 is provided with a movable piston 51, and the distal end is connected to a needle assembly 6, and the axially feeding push rod 42 is used to push the movable piston 51 of the cartridge 5 to move toward the distal end, so as to discharge the drug in the cartridge 5 through the needle assembly 6.

[0051] With the above solution, during the dose setting period, the scale element 21 and the transmission element 22 rotate relative to each other so that the accumulator element 23 rotates along the second axis, and the rotation angle of the accumulator element 23 corresponds to the dose setting amount achieved by the scale element 21, and during the dose injection period, the scale element 21, the transmission element 22 and the accumulator element 23 all remain relatively stationary; therefore, during a complete injection process, the accumulator element 23 can record the dose setting amount by its own rotation, and accordingly, as the user performs injections one by one, the accumulator element 23 can accumulate and record the total amount of the dose setting until the accumulator element 23 reaches the dose setting amount. When the component 23 moves to the stop position where the first stop portion 244 and the second stop portion 234 abut against each other, the accumulating component 23 is restricted from further rotation. At this time, the scale component 21 and the transmission component 22 cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose, and further limiting the final dose setting of the injection device. Accordingly, the final dose setting value is set to be less than or equal to the total amount of medicine that can be injected by the injection device, which can ensure that the set dose is less than or equal to the remaining dose of medicine that can be injected by the injection device, so that the actual injection dose is consistent with the set dose to avoid the situation of injecting the wrong dose.

[0052] It should be noted that the cross 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 are not in the same plane; specifically, if the plane where the first axis is located is defined as the first plane, 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 element where the driving rib 24 is located and the accumulating element 23 has a better transmission efficiency.

[0053] Further, refer to Figure 3 In some embodiments, the movement direction of the first terminating portion 244 when adjusting the dose is defined as the end approach direction, and the end position of the accumulation element 23 is formed when the second terminating portion 234 moves to block the first terminating portion 244 from continuing to move along the end approach direction. It should be noted that the dose setting action is reflected in the relative rotation between the scale element 21 and the transmission element 22, and the relative rotation between the scale element 21 and the transmission element 22 is converted into the rotation of the accumulation element 23 through the cooperation of the driving rib 24 and the accumulation element 23, which is similar to the cooperation transmission structure of the worm thread and the worm gear tooth groove, and belongs to the deceleration motion. Therefore, the dose represented by the movement of the first terminating portion 244 for one unit angle will be less than the dose represented by the movement of the second terminating portion 234 for one unit angle, and the actual manufacturing inevitably has dimensional errors. In the above scheme, compared with limiting the movement of the second terminating portion 234 to limit the end position, limiting the end position by limiting the movement of the first terminating portion 244 can reduce the adverse effect of dimensional errors on dose accumulation.

[0054] Reference Figure 3 In some specific embodiments, the first end portion 244 is configured as the end of the driving rib 24. Accordingly, the second end portion 234 is configured at the outer periphery of the accumulating element 23 for the end of the driving rib 24 to abut against. Figure 6 In some embodiments, the meshing teeth 231 are arranged on the entire circumference of the accumulating element 23, that is, the meshing teeth 231 are arranged in a full circle on the main body of the accumulating element 23; accordingly, the second terminating portion 234 is arranged between two adjacent meshing teeth 231. Figure 7 In other embodiments, the outer circumference of the accumulating element 23 includes a meshing arc segment provided with meshing teeth 231 and a stop arc segment 25 not provided with meshing teeth 231 ; accordingly, the side wall of the stop arc segment 25 serves as the second termination portion 234 .

[0055] Furthermore, combined with Figure 8In some embodiments, the accumulator 23 is also provided with a starting position, and when the accumulator 23 is in the starting position, the scale element 21 is prevented from rotating relative to the transmission element 22 in the direction of reducing the dose. Moreover, the amount of movement of the accumulator 23 between the starting position and the ending position corresponds to the total amount of medicine that can be injected by the injection device. As the accumulator 23 gradually moves from the starting position to the ending position, the remaining movable amount between the accumulator 23 and the ending position always corresponds to the remaining amount of medicine that can be injected in the injection device; therefore, it can be ensured that the dose set each time will not exceed the remaining amount of medicine that can be injected by the injection device, so that the actual injection dose is consistent with the set dose, avoiding the situation of injecting the wrong dose, and thus ensuring that the drug injection obtains its corresponding use effect.

[0056] In a specific embodiment, the element equipped with the driving rib 24 is further provided with a first starting portion 243, and the accumulating element 23 is correspondingly provided with a second starting portion 233; it can be understood that when the driving rib 24 is arranged on the scale element 21, the first starting portion 243 is arranged on the scale element 21, and when the driving rib 24 is arranged on the transmission element 22, the first starting portion 243 is arranged on the transmission element 22. At the same time, the movement direction of the first starting portion 243 when adjusting the dose is defined as the starting approach direction, and the starting position of the accumulating element 23 is formed when the second starting portion 233 moves to block the first starting portion 243 from continuing to move along the starting approach direction.

[0057] Specifically, in some embodiments, the first starting portion 243 is configured as the end of the driving rib 24, and correspondingly, the first ending portion 244 is configured at the outer periphery of the accumulating element 23 for the end of the driving rib 24 to abut against. Figure 6 In some embodiments, the meshing teeth 231 are arranged on the entire circumference of the accumulating element 23, that is, the meshing teeth 231 are arranged in a full circle on the main body of the accumulating element 23; accordingly, the second starting portion 233 is arranged between two adjacent meshing teeth 231. Figure 7 In other embodiments, the outer circumference of the accumulating element 23 includes a meshing arc segment provided with meshing teeth 231 and a stop arc segment 25 not provided with meshing teeth 231 ; accordingly, the side wall of the stop arc segment 25 serves as the second starting portion 233 .

[0058] It should be noted that the movement stroke of the accumulator 23 between the start position and the end position corresponds to the total amount of medicine that can be injected by the injection device, indicating that the movement stroke of the accumulator 23 has a corresponding relationship with the total amount of medicine in the injection device; for the convenience of description, the movement stroke of the accumulator 23 is defined as U, and the ratio of the set dose to the movement amount of the accumulator 23 is defined as T, that is, the sum of the set doses represented by the accumulator 23 in its entire movement stroke is UT, and the total amount of medicine in the injection device is defined as S. In some specific embodiments, UT=S, indicating that the sum of the set doses corresponding to the accumulator 23 in its entire movement stroke is equal to the total amount of medicine in the injection device, so that the medicine in the injection device can be completely injected at the last injection; in other specific embodiments, UT<S, indicating that the sum of the set doses corresponding to the accumulator 23 in its entire movement stroke is less than the total amount of medicine in the injection device, so that after the last injection, some medicine will remain in the injection device and not be injected. In other specific embodiments, when the dose accumulation mechanism 2 is assembled to the injection device, the matching size adjustment is performed, which causes the accumulation element 23 to move from the starting position to the ending position. The movement amount of the accumulation element 23 during assembly and debugging is correspondingly defined as u. In some embodiments, the equation (Uu)T=S is satisfied, that is, the drug in the injection device can be completely injected at the last injection; in other embodiments, the inequality (Uu)T<S is satisfied, that is, some drug will remain in the injection device after the last injection and has not been injected.

[0059] It is understandable that the driving rib 24 can be arranged on the scale element 21, in which case the accumulating element 23 is rotatably connected to the transmission element 22; the driving rib 24 can also be arranged on the transmission element 22, in which case the accumulating element 23 is rotatably connected to the scale element 21.

[0060] Reference Figure 1 and Fig. 9 In some embodiments, the driving rib 24 is disposed on the inner side wall of the scale element 21 and extends on the scale element 21 around the first axis. The accumulating element 23 is completely contained in the scale element 21 and is substantially in the shape of a worm gear. At the same time, the accumulating element 23 is rotatably connected with the transmission element 22 through a rotating shaft, and a clearance zone is provided on the transmission element 22 for the accumulating element 23 to rotate without restriction. In some specific embodiments, the transmission element 22 is provided with a radial through groove 224 in a direction perpendicular to the first axis and the second axis. The accumulating element 23 is installed in the radial through groove 224, and the radial through groove 224 serves as a clearance zone on the transmission element 22 for the accumulating element 23 to rotate freely; and the area of ​​the accumulating element 23 installed in the radial through groove 224 with the meshing groove 232 can protrude from a notch of the radial through groove 224 and mesh with the driving rib 24 on the inner side wall of the scale element 21.

[0061] It should be noted that the driving rib 24 extending on the scale element 21 around the first axis means that the driving rib 24 is arranged on the scale element 21 and extends in a circular manner along its axial direction with the first axis as the spiral axis; accordingly, for the convenience of expression, the two opposite ends of the driving rib 24 along its extension direction are respectively 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.

[0062] In some specific embodiments, the number of turns of the driving rib 24 on the scale element 21 is less than or equal to one, that is, the angle formed by the first end and the second end based on the first axis is less than or equal to 360°. It can be understood that this makes the axial projection of the driving rib 24 along the first axis have no overlapping areas, that is, the axial projection is an arc with a notch or just forms a complete circular ring; so when the scale element 21 and the driving rib 24 thereon are prepared by injection molding, the axially opposed mold cores can be used to form the axially opposite side walls of the driving rib 24, and after injection molding, it is only necessary to axially pull the axially opposed mold cores apart for convenient demoulding.

[0063] Further, refer to Figure 8 and Fig.10 In some specific embodiments in which the driving rib 24 surrounds one circle or less, the driving rib 24 includes a driving section 241 and two engaging sections 242 at the ends of the driving section 241, that is, the driving rib 24 includes an engaging section 242, a driving section 241 and an engaging section 242 connected in sequence along its extension direction; wherein the engaging section 242 is the portion of the driving rib 24 that first engages with the engaging groove 232 on the accumulating element 23, or is the last to disengage from the engaging groove 232 on the accumulating element 23, and the driving section 241 is the portion of the driving rib 24 used to drive the accumulating element 23 to rotate.

[0064] Similarly, for the convenience of subsequent description, the process from the engagement section 242 starting to engage into the engagement groove 232 to the drive section 241 starting to engage into the engagement groove 232 is defined as the engagement process, the process from the drive section 241 starting to engage into the engagement groove 232 to the drive section 241 completely disengaging from the engagement groove 232 is defined as the driving process, and the process from the drive section 241 completely disengaging from the engagement groove 232 to the engagement section 242 completely disengaging from the engagement groove 232 is defined as the disengagement process; accordingly, the accumulation element 23 and the transmission element 22 remain relatively stationary during the engagement process and the disengagement process.

[0065] In the case where the driving rib 24 does not spiral more than one circle, there is a possibility that the driving rib 24 is completely disengaged from the meshing groove 232 on the accumulating element 23, that is, there is a possibility that the first end is disengaged from the meshing groove 232 while the second end has not yet engaged in another meshing groove 232, in which case the accumulating element 23 remains stationary; if the driving rib 24 is set as a continuous spiral section, it is possible that the end of the driving rib 24 is not completely aligned with the meshing groove 232 when it engages in the meshing groove 232 on the accumulating element 23 again, which will cause the accumulating element 23 to rotate additionally, thereby causing the accumulating element 23 to have a cumulative error. By adopting the above scheme, the driving rib 24 can drive the accumulating element 23 to rotate only during the driving process of the driving section 241, while the accumulating element 23 remains stationary during the meshing process and the meshing process of the meshing section 242, so that the end of the driving rib 24 is aligned with the meshing groove 232 when it engages in the meshing groove 232 on the accumulating element 23 again, so as to avoid the situation that the accumulating element 23 rotates additionally and causes the accumulating element 23 to have a cumulative error. By adopting the above scheme, the driving rib 24 can drive the accumulating element 23 to rotate only during the driving process of the driving section 241, and the accumulating element 23 remains stationary during the meshing process and the meshing process of the meshing section 242, so as to ensure that the end of the driving rib 24 is aligned with the meshing groove 232 when it engages in the meshing groove 232 on the accumulating element 23 again, thereby avoiding the situation that the accumulating element

[0066] It should be noted that the total rotation angle of the scale element 21 relative to the transmission element 22 during the dose setting period is defined as the total setting angle, and the total dose that can be accumulated and set by the injection device corresponds to the total setting angle; at the same time, in the embodiment where the drive rib 24 includes the drive segment 241 and the engagement segment 242, the total setting angle is set to an integer multiple of 360°, that is, when the maximum set dose is reached, the scale element 21 rotates an integer number of circles relative to the transmission element 22.

[0067] Further, in some embodiments where the driving rib 24 includes a driving section 241 and an engaging section 242, the engaging section 242 is configured as an arc section arranged around the circumference of the first axis, that is, the engaging section 242 is entirely located on a circle whose center is located on the first axis. It should be noted that the driving rib 24 includes two engaging sections 242, both of which are arc sections, but the two engaging sections 242 are located at different axial positions on the first axis.

[0068] Furthermore, in other embodiments where the driving rib 24 includes a driving segment 241 and an engagement segment 242, the driving segment 241 is configured as a spiral segment spirally arranged around a first axis; the spiral segment is used to engage with the engagement groove 232, and is used to drive the accumulation element 23 to rotate when the spiral segment rotates synchronously with the scale element 21.

[0069] Further, refer to Figures 8 to 11In some embodiments, when the scale element 21 rotates one circle relative to the transmission element 22, the accumulation element 23 is driven to rotate the angle of one tooth; specifically, the central angle formed by the center points of two adjacent meshing grooves 232 on the accumulation element 23 relative to the second axis is defined as a reference angle a, and when the scale element 21 and the transmission element 22 rotate one circle relative to each other, that is, 360°, the rotation angle of the accumulation element 23 is a reference angle a.

[0070] Reference Figure 2 , Fig.12 and Fig.13 In other embodiments, the driving rib 24 is arranged on the outer side wall of the transmission element 22, a support seat 211 is arranged on the inner side of the scale element 21, and the accumulation element 23 is rotatably mounted on the support seat 211; accordingly, an active cavity for the accumulation element 23 to rotate freely is formed between the scale element 21 and the transmission element 22; in some specific embodiments, there is a spacing between the inner side wall of the scale element 21 and the outer side wall of the transmission element 22 on which the driving rib 24 is arranged, so that an annular cavity is formed between the scale element 21 and the transmission element 22, and the annular cavity serves as an active cavity for the accumulation element 23 to rotate freely.

[0071] Further, in some embodiments, the transmission element 22 includes a proximal element 221 and a distal element 222 distributed along the axial direction, wherein the proximal element 221 is used to extend into the scale element 21 from the proximal end of the scale element 21, and the distal element 222 is used to extend into the scale element 21 from the distal end of the scale element 21, the distal end of the proximal element 221 is fixedly connected to the proximal end of the distal element 222, and the area where the proximal element 221 and the distal element 222 are connected forms a part of the cavity wall of the active cavity.

[0072] Further, in some embodiments, a coupling structure is provided between the clutch element 31 and the scale element 21, the coupling structure allows the scale element 21 to rotate relative to the clutch element 31 in the direction of increasing the dose, and prevents the scale element 21 from rotating relative to the clutch element 31 in the direction of decreasing the dose; specifically, referring to Figure 5 and Fig.14The connection structure includes a ratchet tooth ring 212 disposed on the inner side of the scale element 21 and a ratchet arm 311 disposed on the outer side of the clutch element 31. The ratchet tooth ring 212 has ratchet tooth grooves arranged in the circumferential direction. The ratchet arm 311 includes an arc-shaped elastic arm 312 and a ratchet pawl 313 at the free end of the arc-shaped elastic arm 312. The ratchet pawl 313 can be embedded in the ratchet tooth groove. At the same time, the ratchet tooth groove has a first groove wall and a second groove wall opposite to each other in the circumferential direction, and the ratchet pawl 313 has a first side wall 3131 and a second side wall 3132 opposite to each other in the circumferential direction. When the scale element 21 rotates relative to the clutch element 31 in the direction of increasing the dose, the first side wall 3131 abuts against the first groove wall and slides against each other as the two continue to approach each other. When the scale element 21 rotates relative to the clutch element 31 in the direction of decreasing the dose, the second side wall 3132 abuts against the second groove wall and prevents further approach.

[0073] Further, refer to Figure 5 , Fig.15 and Fig.16 In some embodiments, the transmission element 22 is provided with a first meshing portion 223, and the clutch element 31 is provided with a second meshing portion 314 for the first meshing portion 223 to mesh with, and the clutch element 31 can be axially moved from the first mating position to the second mating position relative to the transmission element 22, when the clutch element 31 is in the first mating position, the first meshing portion 223 is meshed with the second meshing portion 314, and when the clutch element 31 is in the second mating position, the first meshing portion 223 is separated from the second meshing portion 314. Correspondingly, the clutch mechanism 3 also includes a pushing element 32 and an elastic element 33, wherein the pushing element 32 is located proximal to the clutch element 31, and the elastic element 33 is located between the pushing element 32 and the elastic element 33 and is specifically configured as a linear spring; specifically, the pushing element 32 can move axially relative to the scale element 21 and has a first position and a second position relative to the scale element 21, the pushing element 32 is in the first position during dose setting, and the pushing element 32 is pushed from the first position to the second position during dose injection, and the pushing element 32 in the second position prevents the clutch element 31 from moving from the first matching position to the second matching position; at the same time, the elastic element 33 provides elastic resistance for the clutch element 31 to move from the first matching position to the second matching position, and provides elastic resistance for the pushing element 32 to move from the first matching position to the second position.

[0074] By adopting the above technical solution, during the period of increasing the dose, the clutch element 31 is in the first matching position to prevent the clutch element 31 from rotating relative to the transmission element 22 in the direction of increasing the dose; during the period of decreasing the dose, the clutch element 31 can move from the first matching position to the second matching position to allow the clutch element 31 to rotate relative to the transmission element 22 in the direction of decreasing the dose; during the period of injecting the dose, the clutch element 31 is prevented from moving from the first matching position to the second matching position to prevent the clutch element 31 from rotating relative to the transmission element 22.

[0075] Combination Fig.15 It should be noted that the first meshing portion 223 and the second meshing portion 314 are both configured as inclined teeth with a cross-section similar to a right-angled triangle, and the inclined teeth have a right-angled surface 3141 and an inclined surface 3142. During dose setting, when the right-angled surface 3141 of the inclined tooth on the axial gear ring abuts against the right-angled surface 3141 of the matching tooth, the clutch element 31 is prevented from rotating relative to the transmission element 22 in the direction of increasing the dose. When the inclined surface 3142 of the inclined tooth on the axial gear ring abuts against the inclined surface 3142 of the matching tooth, the clutch element 31 and the transmission element 22 experience relative axial movement and "tooth jumping" occurs under the elastic force of the elastic element 33, that is, the tooth jumps from one slot to an adjacent slot.

[0076] 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" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0077] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. An injection device capable of limiting the final dose setting, characterized in that: include: a housing having a first axis; a scale element rotatable relative to the housing about a first axis for dose setting; A transmission element, which is inserted into the scale element and can rotate around the first axis; An accumulation element, the accumulation element being rotatable about a second axis, the second axis being arranged crosswise with the first axis, the accumulation element being provided with a second terminating portion and a plurality of meshing grooves, the plurality of meshing grooves being arranged at intervals along the circumferential direction of the second axis; A clutch element, disposed between the scale element and the transmission element; wherein one of the scale element and the transmission element is provided with a first stop portion and a driving rib capable of engaging with the engagement groove, and the accumulation element is rotatably connected to the other of the scale element and the transmission element; During dose setting, one of the scale element and the transmission element is rotatable relative to the clutch element, and the other is rotationally coupled to the clutch element; When the scale element and the transmission element rotate relative to each other, the driving rib drives the accumulation element to rotate, and when the first end portion abuts against the second end portion, the end position of the accumulation element is formed. When the accumulation element is in the end position, the scale element is prevented from rotating relative to the transmission element in the direction of increasing the dose; during dose injection, the clutch element locks the scale element and the transmission element in the rotation direction.

2. The injection device capable of limiting the final dose setting according to claim 1, characterized in that: The movement direction of the first terminating portion when increasing the dose is defined as a terminating approach direction, and the terminating position of the accumulating element is formed when the second terminating portion moves to block the first terminating portion from continuing to move along the terminating approach direction.

3. The injection device capable of limiting the final dose setting according to claim 2, characterized in that: The first termination portion is configured as an end portion of the driving rib.

4. The injection device capable of limiting the final dose setting according to claim 3, characterized in that: The second end portion is disposed on the outer periphery of the accumulating element for the end of the driving rib to abut against.

5. The injection device capable of limiting the final dose setting according to claim 2, characterized in that: The element equipped with the driving rib is also provided with a first starting part, and the accumulating element is provided with a second starting part. The movement direction of the first starting part when reducing the dose is defined as the starting approach direction. When the second starting part moves to block the first starting part from continuing to move along the starting approach direction, the starting position of the accumulating element is formed. When the accumulating element is in the starting position, the scale element is prevented from rotating relative to the transmission element in the direction of reducing the dose.

6. The injection device capable of limiting the final dose setting according to claim 1, characterized in that: The driving rib is arranged on the outer side wall of the transmission element, and the accumulating element is rotatably connected to the scale element.

7. The injection device capable of limiting the final dose setting according to claim 6, characterized in that: The transmission element includes a proximal element and a distal element distributed along the axial direction, the proximal element is used to extend into the scale element from the proximal end of the scale element, and the distal element is used to extend into the scale element from the distal end of the scale element, and the distal end of the proximal element is fixedly connected to the proximal end of the distal element.

8. The injection device capable of limiting the final dose setting according to claim 1, characterized in that: The driving rib is arranged on the inner side wall of the scale element, and the accumulating element is rotatably connected to the transmission element.

9. The injection device capable of limiting the final dose setting according to claim 8, characterized in that: The driving rib extends on the scale element around the first axis, and 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 or equal to 360°.

10. The injection device capable of limiting the final dose setting according to claim 9, characterized in that: The driving rib includes a driving section and an engaging section at the end of the driving section. The engaging process is defined as the process from when the engaging section starts to engage with the engaging groove to when the driving section starts to engage with the engaging groove. The disengaging process is defined as the process from when the driving section completely disengages from the engaging groove to when the engaging section completely disengages from the engaging groove. During the engaging process and the disengaging process, the accumulating element and the transmission element remain relatively stationary.

11. The injection device capable of limiting the final dose setting according to claim 1, characterized in that: A coupling structure is provided between the clutch element and the scale element, which allows the scale element to rotate relative to the clutch element in a direction of increasing the dose and prevents the scale element from rotating relative to the clutch element in a direction of decreasing the dose.

12. The injection device capable of limiting the final dose setting according to claim 11, characterized in that: The coupling structure comprises a ratchet tooth ring arranged on the inner side of the scale element and a ratchet arm arranged on the outer side of the clutch element, wherein the ratchet tooth ring has ratchet tooth grooves arranged along the circumferential direction, and the ratchet arm comprises an arc-shaped elastic arm and a pawl at the free end of the arc-shaped elastic arm, and the pawl can be embedded in the ratchet tooth groove; The ratchet tooth groove has a first groove wall and a second groove wall opposite to each other in a circumferential direction, and the pawl has a first side wall and a second side wall opposite to each other in a circumferential direction; when the scale element rotates in a direction of increasing the dose relative to the clutch element, the first side wall abuts against the first groove wall and slides against each other as the two continue to approach each other; when the scale element rotates in a direction of decreasing the dose relative to the clutch element, the second side wall abuts against the second groove wall and prevents further approach.

13. The injection device capable of limiting the final dose setting according to claim 1, characterized in that: The transmission element is provided with a first meshing portion, and the clutch element is provided with a second meshing portion for the first meshing portion to mesh with. The clutch element can be axially moved from a first matching position to a second matching position relative to the transmission element. When the clutch element is in the first matching position, the first meshing portion is meshed with the second meshing portion, and when the clutch element is in the second matching position, the first meshing portion is separated from the second meshing portion. During the dose increase, the clutch element is in the first engagement position to prevent the clutch element from rotating relative to the transmission element in the dose increase direction; During dose reduction, the clutch element can move from the first engagement position to the second engagement position to allow the clutch element to rotate relative to the transmission element in a dose reduction direction; During dose injection, the clutch element is prevented from moving from the first engagement position to the second engagement position, thereby preventing the clutch element from rotating relative to the transmission element.

14. The injection device capable of limiting the final dose setting according to claim 13, characterized in that: The injection device further comprises a pushing element and an elastic element, wherein the pushing element is located near the clutch element, and the elastic element is located between the pushing element and the elastic element; The pushing element can move axially relative to the scale element and has a first position and a second position relative to the scale element. During dose setting, the pushing element is in the first position. During dose injection, the pushing element is pushed from the first position to the second position. The pushing element in the second position prevents the clutch element from moving from the first matching position to the second matching position. The elastic element provides elastic resistance for the clutch element to move from the first matching position to the second matching position, and the elastic element provides elastic resistance for the push element to move from the first position to the second position.

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