Dose accumulation mechanism and injection device

Abstract

The invention relates to a dose accumulation mechanism and an injection device, the dose accumulation mechanism comprises a first element, and the first element is provided with a driving rib; the second element is sleeved with the first element; the accumulation element is connected to the second element, the accumulation element is provided with a plurality of meshing teeth, and a meshing groove allowing the driving rib to be meshed in is formed between every two adjacent meshing teeth; wherein during dose setting, the first element is rotatable relative to the second element in a first direction to increase the dose and in a second direction to decrease the dose, and the driving rib is configured to cooperate with the meshing teeth to drive the accumulation element to rotate; the accumulation element is provided with a starting position and a stopping position, the movement stroke of the accumulation element between the starting position and the stopping position corresponds to the total amount of medicine capable of being injected by the injection device, and when the accumulation element is located at the stopping position, the first element is limited to further rotate in the first direction relative to the second element. According to the invention, the actual injection dose can be consistent with the set dose, so that injection of wrong doses is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of injection devices, and in particular to a dose accumulation mechanism and an injection device. 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 set the dose based on needs and inject the set dose. At the same time, the process of the user setting the dose and then injecting the set dose is regarded as a complete injection.

[0003] 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 set injection dose, and may result in the wrong dose being injected, thereby affecting the effect of the drug injection. Summary of the invention

[0004] On the one hand, 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 to avoid the situation where the wrong dose is injected, the present application provides a dose accumulation mechanism.

[0005] A dose accumulation mechanism provided in this application adopts the following technical solution:

[0006] A dose accumulation mechanism, comprising: a first element, which can rotate around a first axis, the first element is provided with a driving rib, and the driving rib extends on the first element around the first axis; a second element, which is sleeved with the first element and can rotate around the first axis; an accumulation element, which is connected to the second element and can rotate around a second axis relative to the second element, the second axis is arranged crosswise with the first axis, the accumulation element is provided with a plurality of meshing teeth, the plurality of meshing teeth are arranged at intervals along the circumferential direction of the second axis, and a meshing groove for the driving rib to engage is formed between two adjacent meshing teeth; wherein, during dose setting, the The first element can rotate relative to the second element in a first direction to increase the dose, and rotate relative to the second direction to decrease the dose, and the driving rib is used to cooperate with the meshing teeth to drive the accumulation element to rotate; during dose injection, the first element is anti-rotationally connected to the second element, and the accumulation element is stationary relative to the first element and the second element; the accumulation element has a starting position and an ending position, and the movement stroke of the accumulation element between the starting position and the ending position corresponds to the total amount of medicine that can be injected by the injection device, and when the accumulation element is in the ending position, the first element is restricted from further rotating relative to the second element in the first direction.

[0007] By adopting the above technical solution, during the dose setting period, the first element and the second 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, and during the dose injection period, the first element, the second element and the accumulation element all remain relatively stationary; therefore, in a complete injection process, the accumulation element can record the dose setting amount by its own rotation, and accordingly, as the user performs injections one by one, the accumulation element can accumulate the total amount of dose setting, until the accumulation element moves to the end position, the first element and the second element cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose. At the same time, the movement amount of the accumulation element between the starting position and the end position corresponds to the total amount of medicine that can be injected by the injection device, and as the accumulation element gradually moves from the starting position to the end position, the remaining movable amount between the accumulation element and the end position always corresponds to the remaining drug dose that can be injected in the injection device; therefore, it can be ensured that the dose set each time will not exceed the remaining drug dose 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 due medical effect.

[0008] Further, the first element is provided with a first stop portion, which moves with the first element around the first axis, and the accumulating element is provided with a second stop portion, which moves with the accumulating element around the second axis; when the first stop portion and the second stop portion abut against each other, the starting position or the ending position is formed.

[0009] By adopting the above technical solution, the first element and the accumulating element have a transmission relationship and constitute relative motion. When the first stop portion and the second stop portion abut against each other, the relative motion of the first element and the accumulating element can be limited, thereby forming the starting position or the ending position of the accumulating element.

[0010] Further, the starting position or the ending position is formed when the second stop portion blocks the first stop portion from continuing to move around the first axis along with the first element.

[0011] In actual use, the action of dose setting is reflected as the relative rotation between the first element and the second element, and the relative rotation between the first element and the second element is converted into the rotation of the cumulative element through the cooperation between the driving rib on the first element and the meshing groove on the cumulative element, and the cooperation between the driving rib on the first element and the meshing groove on the cumulative element is similar to the cooperation between the worm thread and the worm gear tooth groove, and the motion transmission between the first element and the cumulative element belongs to deceleration motion. Therefore, the dose represented by the movement of the first stopper by one unit angle will be smaller than the dose represented by the movement of the second stopper by one unit angle, and the actual manufacturing inevitably has dimensional errors. In the above scheme, compared with limiting the movement of the second stopper to limit the starting position or the end position, limiting the movement of the first stopper to limit the starting position or the end position can reduce the adverse effect of dimensional errors on the total stroke control accuracy of the cumulative element, that is, the stroke of the cumulative element between the starting position and the end position has a higher accuracy.

[0012] Further, the first stop portion includes a first starting portion, and the second stop portion includes a second starting portion; the movement direction of the first starting portion when reducing the dose is defined as a starting approach direction, and the starting position of the accumulation element is formed when the second starting portion moves to block the first starting portion from continuing to move along the starting approach direction.

[0013] Further, the first starting portion is configured as an end portion of the driving rib.

[0014] Furthermore, the second starting portion is arranged between two adjacent meshing teeth.

[0015] Further, the first stop portion includes a first stop portion, and the second stop portion includes a second stop portion; the movement direction of the first stop portion when increasing the dose is defined as a stop approach direction, and the stop position of the accumulation element is formed when the second stop portion moves to block the first stop portion from continuing to move along the stop approach direction.

[0016] Further, the first terminating portion is configured as an end portion of the driving rib.

[0017] Furthermore, the second terminating portion is disposed between two adjacent meshing teeth.

[0018] 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 or equal to 360°.

[0019] By adopting the above technical solution, there is no staggered or overlapping area in the axial projection of the driving ribs. Therefore, when the first element and the driving ribs thereon are prepared by injection molding, axially opposed mold cores can be used to form the axially opposite side walls of the driving ribs. After injection molding, demolding can be conveniently performed by axially pulling out the axially opposed mold cores.

[0020] 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 and enter the engaging groove to the driving section starting to engage and enter the engaging groove is defined as an engaging 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 a disengaging process. During the engaging process and the disengaging process, the accumulation element and the second element remain relatively stationary.

[0021] Further, the driving segment is configured as a spiral segment spirally arranged around the first axis, the spiral segment is used to engage in the engagement groove, and is used to drive the accumulating element to rotate when the spiral segment rotates synchronously with the first element.

[0022] Further, the engagement segment is configured as an arc segment circumferentially arranged around the first axis.

[0023] Furthermore, the driving rib has a first end and a second end opposite to each other along its extension direction, a wrap angle formed by the first end and the second end based on the first axis is greater than 360°, and the driving rib spirally extends from the first end to the second end around the first axis.

[0024] Furthermore, the central angle between the center points of two adjacent meshing grooves on the accumulating element and the second axis is defined as a reference angle. When the first element and the second element rotate 360° relative to each other, the rotation angle of the accumulating element is a reference angle.

[0025] Furthermore, the first element is sleeved outside the second element, the driving rib is arranged on the inner side wall of the first element, and the second element is provided with an escape area for the accumulating element to rotate.

[0026] Furthermore, the second element is sleeved outside the first element, the driving rib is arranged on the outer side wall of the first element, and an active cavity for the accumulation element to rotate is formed between the first element and the second element.

[0027] On the second aspect, 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, the present application provides an injection device.

[0028] The present application provides an injection device that adopts the following technical solution:

[0029] An injection device comprises a clutch element and the above-mentioned dose accumulation mechanism, wherein during dose setting, at least one of the first element and the second element can rotate relative to the clutch element; during dose injection, the clutch element is connected to the first element and the second element in a rotationally-resistant manner in the dose injection direction.

[0030] In summary, this application at least includes the following beneficial effects:

[0031] During a complete injection process, the accumulator can record the dose setting amount by rotating itself. Accordingly, as the user performs injections one by one, the accumulator can accumulate the total amount of dose setting. When the accumulator moves to the end position, the first element and the second element cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose. At the same time, as the accumulator moves from the starting position to the end position, the remaining movable amount between the accumulator and the end position always corresponds to the remaining drug dose that can be injected in the injection device. Therefore, it can ensure that the dose set each time will not exceed the remaining drug dose that can be injected by the injection device, so that the actual injection dose is consistent with the set dose, avoiding the injection of the wrong dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram of an injection device with a dose accumulation mechanism in an embodiment of the present application;

[0033] Figure 2is a schematic diagram of another injection device with a dose accumulation mechanism in an embodiment of the present application;

[0034] Figure 3 It is a schematic diagram used to show the second element and the accumulation element in the embodiment of the present application. Figure 1 ;

[0035] Figure 4 is a schematic diagram for illustrating a first element and an accumulation element in an embodiment of the present application;

[0036] Figure 5 It is a schematic diagram used to show the second element and the accumulation element in the embodiment of the present application. Figure 2 ;

[0037] Figure 6 is a schematic diagram for illustrating a first element, a second element and a clutch element in an embodiment of the present application;

[0038] Figure 7 is an exploded schematic diagram of the first element, the second element and the clutch element in the embodiment of the present application;

[0039] Figure 8 is a schematic diagram for illustrating the axial gear ring on the second element in an embodiment of the present application;

[0040] Fig. 9 is a schematic diagram used to show that the second element and the accumulation element form a starting position in the embodiment of the present application;

[0041] Fig.10 is a schematic diagram used to show that the second element and the accumulation element form a termination position in the embodiment of the present application;

[0042] Fig.11 This is a schematic diagram used to show the formation of a starting position between the first element and the accumulation element in the embodiment of the present application. Figure 1 ;

[0043] Fig.12 This is a schematic diagram used to show the termination position formed by the first element and the accumulation element in the embodiment of the present application. Figure 1 ;

[0044] Fig.13 This is a schematic diagram of hiding a partial side wall of the first element in the embodiment of the present application to show the first element and the accumulation element forming a starting position Figure 2 ;

[0045] Fig.14 It is a schematic diagram used to show that meshing teeth are provided on the circumference of the accumulation element in the embodiment of the present application;

[0046] Fig.15 is a schematic diagram for showing that the accumulating element includes a stop arc segment and an engagement arc segment in an embodiment of the present application;

[0047] Fig.16 This is a schematic diagram of hiding a partial side wall of the first element in the embodiment of the present application to show that the first element and the accumulation element form a termination position. Figure 2 ;

[0048] Fig.17 is a schematic diagram of an embodiment of the present application in which a partial side wall of the first element is hidden to display the driving ribs;

[0049] Fig.18 is a schematic diagram for illustrating a reference angle on an accumulation element in an embodiment of the present application;

[0050] Fig.19 It is a schematic diagram used to show the mating teeth on the clutch element in the embodiment of the present application.

[0051] Description of the reference numerals: 1. first element; 11. driving rib; 111. driving section; 112. engaging section; 12. ratchet tooth ring; 13. initial interference portion; 14. termination interference portion; 15. first starting portion; 16. first termination portion; 2. second element; 21. radial through groove; 22. axial tooth ring; 23. stop bar; 231. first stop surface; 232. second stop surface; 24. support seat; 3. accumulating element; 31. meshing teeth; 32. Engaging groove; 33, rotating shaft; 34, convex strip; 341, first abutting surface; 342, second abutting surface; 35, stop strip; 36, second starting part; 37, second ending part; 38, engaging arc segment; 39, stop arc segment; 4, clutch element; 41, ratchet arm; 42, matching tooth; 421, right-angle surface; 422, inclined surface; 5, driving rod; 6, push rod; 7, shell; 8, cartridge bottle; 81, movable piston; 9, button; 10, spring. DETAILED DESCRIPTION

[0052] 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.

[0053] 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.

[0054] 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.

[0055] The embodiment of the present application discloses a dose accumulation mechanism for an injection device, which can 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 injection dose is consistent with the set dose to avoid the situation where the wrong dose is injected.

[0056] Reference Figure 1 and Figure 2 The dose accumulation mechanism comprises a first element 1, a second element 2 and an accumulation element 3, and the dose accumulation mechanism is installed in a housing 7 of the injection device, and the central axis of the housing 7 is defined as a first axis.

[0057] Among them, the first element 1 can rotate around a first axis, and the first element 1 is provided with a driving rib 11, and the driving rib 11 extends on the first element 1 around the first axis; the second element 2 is socketed with the first element 1, and the second element 2 can rotate around the first axis; the accumulation element 3 is connected to the second element 2, and the accumulation element 3 can rotate around a second axis relative to the second element 2, the second axis is the central axis of the accumulation element 3, and the second axis is arranged crosswise with the first axis; at the same time, the accumulation element 3 is provided with a plurality of meshing teeth 31, and the plurality of meshing teeth 31 are arranged at intervals along the circumferential direction of the second axis, so that a meshing groove 32 for the driving rib 11 to engage is formed between two adjacent meshing teeth 31.

[0058] Specifically, during the dose setting, the first element 1 and the second element 2 can rotate relative to each other, and the dose setting includes increasing the dose and decreasing the dose; accordingly, when the first element 1 rotates relative to the second element 2 in the first direction, it is used to increase the dose, and when the first element 1 rotates relative to the second element 2 in the second direction, it is used to decrease the dose, and the first direction is opposite to the second direction. At the same time, during the entire dose setting period, the driving rib 11 is used to cooperate with the meshing teeth 31 to drive the cumulative element 3 to rotate. During the dose injection, the first element 1 and the second element 2 are anti-rotationally connected so that the first element 1 and the second element 2 rotate synchronously or are synchronously stationary, during which the cumulative element 3 is stationary relative to the first element 1 and the second element 2 without rotating around the second axis. In addition, the cumulative element 3 has a starting position and an end position of movement, and the movement stroke of the cumulative element 3 between the starting position and the end position corresponds to the total amount of medicine that can be injected by the injection device, and when the cumulative element 3 is in the end position, the first element 1 is restricted from further rotating relative to the second element 2 in the first direction, that is, the further increase of the dose is restricted.

[0059] With the above scheme, during dose setting, the first element 1 and the second element 2 rotate relative to each other so that the accumulation element 3 rotates along the second axis, and the rotation angle of the accumulation element 3 corresponds to the dose setting amount, while during dose injection, the first element 1, the second element 2 and the accumulation element 3 all remain relatively stationary; in a complete injection process, the accumulation element 3 can record the dose setting amount by its own rotation, and accordingly, as the user performs successive injections, the accumulation element 3 can accumulate the total amount of the dose setting until the accumulation element 3 moves to the end position, and the first element 1 and the second element 2 cannot further rotate in the direction of increasing the dose, thereby limiting the further increase of the set dose. At the same time, the amount of movement of the accumulating element 3 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 accumulating element 3 gradually moves from the starting position to the ending position, the remaining movable amount between the accumulating element 3 and the ending position always corresponds to the remaining medicine dose that can be injected in the injection device; therefore, it can be ensured that the dose set each time will not exceed the remaining medicine dose 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.

[0060] It should be noted that the movement stroke of the accumulator 3 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 3 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 3 is defined as U, and the ratio of the set dose to the movement amount of the accumulator 3 is defined as T, that is, the sum of the set doses represented by the accumulator 3 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 3 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 in the last injection; in other specific embodiments, UT<S, indicating that the sum of the set doses corresponding to the accumulator 3 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 is assembled to the injection device, the matching size adjustment is performed, which causes the accumulation element 3 to move from the starting position to the ending position. The movement amount of the accumulation element 3 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.

[0061] It should also 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 first element 1 and the accumulating element 3 has a better transmission efficiency.

[0062] It can be understood that the second element 2 and the first element 1 can be sleeved together in such a way that the first element 1 is sleeved outside the second element 2 , or the second element 2 is sleeved outside the first element 1 .

[0063] Reference Figure 1 and Figure 3In some embodiments, the first element 1 is sleeved on the outside of the second element 2. The first element 1 is roughly cylindrical, and the driving rib 11 is arranged on the inner side wall of the first element 1; the second element 2 is roughly cylindrical, and the second element 2 is at least partially accommodated in the first element 1, and the accumulation element 3 is completely accommodated in the first element 1 and is roughly worm-shaped. At the same time, the accumulation element 3 is rotatably connected with the second element 2 through the rotating shaft 33. Accordingly, the second element 2 is provided with an escape zone for the accumulation element 3 to rotate without restriction. In some specific embodiments, the second element 2 is provided with a radial through groove 21 in a direction perpendicular to the first axis and the second axis, and the accumulation element 3 is installed in the radial through groove 21, and the radial through groove 21 serves as an escape zone for the accumulation element 3 to rotate freely on the second element 2; and the area of ​​the accumulation element 3 installed in the radial through groove 21 with the meshing groove 32 can protrude from a notch of the radial through groove 21 and mesh with the driving rib 11 on the inner side wall of the first element 1.

[0064] In the above embodiment, during dose setting, the first element 1 rotates around the first axis while the second element 2 remains stationary, and during dose injection, the first element 1 rotates synchronously with the second element 2. It can be understood that if the first element 1 is defined to rotate clockwise relative to the housing 7 when the dose is increased and to rotate counterclockwise relative to the housing 7 when the dose is decreased, then the rotation of the first element 1 relative to the second element 2 in the first direction corresponds to the second element 2 being stationary while the first element 1 rotates clockwise, and the rotation of the first element 1 relative to the second element 2 in the second direction corresponds to the second element 2 being stationary while the first element 1 rotates counterclockwise; and the first direction is the clockwise direction and the second direction is the counterclockwise direction.

[0065] Reference Figure 2 , Figure 4 and Figure 5 In other embodiments, the second element 2 is sleeved on the outside of the first element 1. The second element 2 is roughly cylindrical, and the accumulation element 3 is completely contained in the second element 2 and is roughly in the shape of a worm gear. At the same time, a support seat 24 is provided on the inner side of the second element 2, and the accumulation element 3 is rotatably mounted on the support seat 24 of the second element 2; the first element 1 is at least partially contained in the second element 2, and the driving rib 11 is arranged on the outer side wall of the first element 1. Accordingly, an active cavity for the accumulation element 3 to rotate freely is formed between the first element 1 and the second element 2; in some specific embodiments, there is a spacing between the inner side wall of the second element 2 and the outer side wall of the first element 1 on which the driving rib 11 is provided, so that an annular cavity is formed between the first element 1 and the second element 2, and the annular cavity serves as an active cavity for the accumulation element 3 to rotate freely.

[0066] In the above embodiment, during the dose setting, the second element 2 rotates around the first axis while the second element 2 remains stationary, and during the dose injection, the second element 2 rotates synchronously with the first element 1. If the second element 2 is defined to rotate clockwise relative to the housing 7 when the dose is increased, and to rotate counterclockwise relative to the housing 7 when the dose is decreased, it can be understood that the rotation of the first element 1 relative to the second element 2 in the first direction corresponds to the first element 1 being stationary while the second element 2 is rotating clockwise, and the rotation of the first element 1 relative to the second element 2 in the second direction corresponds to the first element 1 being stationary while the second element 2 is rotating counterclockwise, and the first direction is counterclockwise and the second direction is clockwise.

[0067] Reference Figure 1 and Figure 6 It should be noted that when the dose accumulation mechanism is configured in the injection device, the first element 1 and the second element 2 are selectively connected in the rotation direction through the clutch element 4, so that the first element 1 and the second element 2 can rotate relative to each other during the dose setting period and can rotate synchronously during the dose injection period. During the dose setting period, at least one of the first element 1 and the second element 2 can rotate relative to the clutch element 4, so that the first element 1 and the second element 2 can rotate relative to each other; during the dose injection period, the first element 1 and the second element 2 are both anti-rotationally connected to the clutch element 4, so that the first element 1 and the second element 2 can rotate synchronously or be stationary synchronously.

[0068] Reference Figure 6 and Figure 7 In some specific embodiments, the first element 1 is sleeved on the outside of the second element 2, and the proximal end of the second element 2 is accommodated in the proximal end of the first element 1. At the same time, the clutch element 4 is located at the proximal end of the first element 1 and presses against the proximal end of the second element 2. At the same time, when the dose is increased, the first element 1 rotates along the third direction, when the dose is decreased, the first element 1 rotates along the fourth direction opposite to the third direction, and when the dose is injected, both the first element 1 and the second element 2 rotate along the fourth direction. Specifically, the third direction is clockwise, and the fourth direction is counterclockwise.

[0069] Accordingly, refer to Figure 6 A ratchet tooth ring 12 is provided on the inner wall of the proximal end of the first element 1, and a ratchet arm 41 matching with the ratchet tooth ring 12 is provided on the clutch element 4. The ratchet tooth ring 12 and the ratchet arm 41 match to form a first connection. The first connection allows the first element 1 to rotate along the third direction relative to the clutch element 4, while preventing the first element 1 from rotating along the fourth direction relative to the clutch element 4.

[0070] Reference Figure 7 and Figure 8, the proximal portion of the second element 2 is provided with an axially protruding axial toothed ring 22, and the clutch element 4 is provided with matching teeth 42 meshing with the axial toothed ring 22, and the axial toothed ring 22 and the matching teeth 42 cooperate to form a second connection, and the second connection prevents the clutch element 4 from rotating in the third direction relative to the second element 2, and allows the clutch element 4 and the second element 2 to have relative axial movement so that the clutch element 4 rotates in the fourth direction relative to the second element 2. At the same time, during the dose injection, the clutch element 4 is pressed against the proximal end of the second element 2 by the axial force, and at this time, the clutch element 4 and the second element 2 cannot have axial movement, so that the clutch element 4 and the second element 2 are relatively stationary.

[0071] In summary, when the first element 1 rotates along the third direction to increase the dose, the clutch element 4 and the second element 2 remain stationary, and the first element 1 rotates relative to the second element 2 and the clutch element 4; when the first element 1 rotates along the fourth direction to decrease the dose, the first element 1 drives the clutch element 4 to rotate along the fourth direction, and the second element 2 remains stationary, and the first element 1 and the clutch element 4 rotate relative to the second element 2. During the dose injection, the first element 1, the clutch element 4 and the second element 2 rotate synchronously along the fourth direction.

[0072] It can be understood that the accumulation element 3 can move relative to the first element 1 and can also move relative to the second element 2. Accordingly, the starting position of the accumulation element 3 can be composed of the accumulation element 3 and the first element 1, or the accumulation element 3 and the second element 2, and the ending position of the accumulation element 3 can be composed of the accumulation element 3 and the first element 1, or the accumulation element 3 and the second element 2.

[0073] In some embodiments, an abutting structure is provided between the accumulating element 3 and the second element 2 to form a starting position and / or an ending position of the accumulating element 3 .

[0074] Reference Fig. 9 In some embodiments where the accumulation element 3 cooperates with the second element 2 to form a starting position, the accumulation element 3 has two side walls arranged opposite to each other along the second axis, and a convex strip 34 is arranged on one of the side walls of the accumulation element 3, the convex strip 34 can rotate with the accumulation element 3, and the convex strip 34 has a first abutting surface 341; accordingly, the second element 2 is provided with a stop bar 23, and the stop bar 23 has a first stop surface 231. When the first abutting surface 341 of the convex strip 34 abuts against the first stop surface 231 of the stop bar 23, the accumulation element 3 is stationary relative to the second element 2 to form the starting position of the accumulation element 3.

[0075] Reference Fig.10In some embodiments where the accumulation element 3 cooperates with the second element 2 to form a termination position, the accumulation element 3 has two side walls arranged opposite to each other along the second axis, and a convex strip 34 is arranged on one of the side walls of the accumulation element 3, the convex strip 34 can rotate with the accumulation element 3, and the convex strip 34 has a second abutting surface 342; correspondingly, the second element 2 is provided with a stopper strip 23, and the stopper strip 23 has a second stop surface 232. When the second abutting surface 342 of the convex strip 34 abuts against the second stop surface 232 of the stopper strip 23, the accumulation element 3 is stationary relative to the second element 2 to form the termination position of the accumulation element 3.

[0076] Reference Fig. 9 and Fig.10 In some embodiments where the accumulation element 3 cooperates with the second element 2 to form a starting position and a termination position, the accumulation element 3 has two side walls arranged opposite to each other along the second axis, and a convex strip 34 is arranged on one of the side walls of the accumulation element 3. The convex strip 34 can rotate with the accumulation element 3, and the convex strip 34 has a first abutting surface 341 and a second abutting surface 342 opposite to each other along its movement direction; accordingly, the second element 2 is provided with a stop bar 23, and the stop bar 23 has a first stop surface 231 and a second stop surface 232 opposite to each other. When the first abutting surface 341 of the convex strip 34 abuts against the first stop surface 231 of the stop bar 23, the starting position of the accumulation element 3 is formed, and when the second abutting surface 342 of the convex strip 34 abuts against the second stop surface 232 of the stop bar 23, the termination position of the accumulation element 3 is formed.

[0077] In other embodiments, an abutting structure is provided between the accumulation element 3 and the first element 1 to form the starting position and / or the ending position of the accumulation element 3. Specifically, the first element 1 is provided with a first stopper, which moves with the first element 1 around the first axis, and the accumulation element 3 is provided with a second stopper, which moves with the accumulation element 3 around the second axis; when the first stopper abuts against the second stopper, the starting position is formed, or when the first stopper abuts against the second stopper, the ending position is formed.

[0078] In some embodiments where the accumulation element 3 cooperates with the first element 1 to form the starting position, the first stopper blocks the second stopper from continuing to move with the accumulation element 3 around the second axis to form the starting position; Fig.11 In a specific embodiment, the first stop portion includes an initial interference portion 13 arranged on the side wall of the first element 1. The initial interference portion 13 can be configured as an arc-shaped protrusion or a convex ring surrounding the first element 1. The second stop portion includes a stop bar 35 protruding radially from the accumulation element 3; when the stop bar 35 moves with the accumulation element 3 to abut against the initial interference portion 13, the accumulation element 3 is prevented from further rotation, thereby forming the starting position of the accumulation element 3.

[0079] In some embodiments where the accumulation element 3 cooperates with the first element 1 to form a stop position, the first stop portion blocks the second stop portion from continuing to move with the accumulation element 3 around the second axis to form the stop position; Fig.12 In a specific embodiment, the first stop portion includes a termination resistance portion 14 arranged on the side wall of the first element 1, and the termination resistance portion 14 can be configured as an arc-shaped protrusion or a protruding ring surrounding the first element 1; the second stop portion includes a stop bar 35 protruding radially from the accumulation element 3; when the stop bar 35 moves with the accumulation element 3 to abut against the termination resistance portion 14, the accumulation element 3 is prevented from further rotation, thereby forming the termination position of the accumulation element 3.

[0080] In other embodiments where the accumulation element 3 cooperates with the first element 1 to form the starting position, the second stopper blocks the first stopper from continuing to move with the first element 1 around the first axis to form the starting position; Fig.13 In a specific embodiment, the first stop portion includes a first starting portion 15, and the second stop portion includes a second starting portion 36. The movement direction of the first starting portion 15 during the dose reduction is defined as the starting approach direction, and the starting position of the accumulating element 3 is formed when the second starting portion 36 moves to block the first starting portion 15 from continuing to move along the starting approach direction.

[0081] Specifically, in some embodiments, the first starting portion 15 is configured as an end portion of the driving rib 11 .

[0082] Specifically, refer to Fig.14 In some embodiments, meshing teeth 31 are arranged on the entire circumference of the accumulating element 3, that is, the meshing teeth 31 are arranged in a full circle on the main body of the accumulating element 3; accordingly, the second starting portion 36 is arranged between two adjacent meshing teeth 31. Fig.15 In other embodiments, the outer circumference of the accumulating element 3 includes a meshing arc segment 38 provided with meshing teeth 31 and a stop arc segment 39 not provided with meshing teeth 31 ; accordingly, the side wall of the stop arc segment 39 serves as the second starting portion 36 .

[0083] In other embodiments where the accumulation element 3 cooperates with the first element 1 to form the starting position, the second stopper blocks the first stopper from continuing to move with the first element 1 around the first axis to form the ending position; Fig.16 In a specific embodiment, the first stop portion includes a first stop portion 16, and the second stop portion includes a second stop portion 37; the movement direction of the first stop portion 16 when increasing the dose is defined as the terminating approach direction, and the terminating position of the accumulating element 3 is formed when the second stop portion 37 moves to block the first stop portion 16 from continuing to move along the terminating approach direction.

[0084] Specifically, in some embodiments, the first termination portion 16 is configured as an end portion of the driving rib 11 .

[0085] Specifically, refer to Fig.14 In some embodiments, meshing teeth 31 are arranged on the entire circumference of the accumulating element 3, that is, the meshing teeth 31 are arranged in a full circle on the main body of the accumulating element 3; accordingly, the second terminating portion 37 is arranged between two adjacent meshing teeth 31. Fig.15 In other embodiments, the outer circumference of the accumulating element 3 includes a meshing arc segment 38 provided with meshing teeth 31 and a stop arc segment 39 not provided with meshing teeth 31 ; accordingly, the side wall of the stop arc segment 39 serves as the second termination portion 37 .

[0086] It should be noted that the driving rib 11 extending on the first element 1 around the first axis means that the driving rib 11 is arranged on the first element 1 and extends in a circumferential manner along the axial direction with the first axis as the spiral axis; accordingly, for the convenience of expression, the two opposite ends of the driving rib 11 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.

[0087] In some embodiments, the number of turns of the driving rib 11 on the first element 1 is greater than or equal to one, that is, the wrap angle formed by the first end and the second end based on the first axis is greater than 360°. It can be understood that this makes the axial projection of the driving rib 11 along the first axis present a closed circular ring shape, and when the aforementioned wrap angle is greater than 360°, there are staggered overlapping areas on the axial projection. At the same time, the driving rib 11 is configured as a spiral segment as a whole, that is, the driving rib 11 spirally extends from the first end to the second end around the first axis.

[0088] In other embodiments, the number of turns of the driving rib 11 on the first element 1 is less than 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 11 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 first element 1 and the driving rib 11 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 11, and after injection molding, it is convenient to demould by simply axially pulling out the axially opposed mold cores.

[0089] Further, refer to Fig.17In some specific embodiments in which the driving rib 11 is surrounded by less than one circle, 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 an engaging section 112, a driving section 111 and an engaging section 112 connected in sequence along its extension direction; wherein the engaging section 112 is the portion of the driving rib 11 that first engages with the engaging groove 32 on the accumulating element 3, or last disengages from the engaging groove 32 on the accumulating element 3, and the driving section 111 is the portion of the driving rib 11 used to drive the accumulating element 3 to rotate.

[0090] Similarly, to facilitate subsequent description, the process from the engagement section 112 starting to engage into the engagement groove 32 to the driving section 111 starting to engage into the engagement groove 32 is defined as the engagement process, the process from the driving section 111 starting to engage into the engagement groove 32 to the driving section 111 completely disengaging from the engagement groove 32 is defined as the driving process, and the process from the driving 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 accumulation element 3 and the second element 2 remain relatively stationary during the engagement process and the disengagement process.

[0091] In the case where the driving rib 11 spirals around less than one circle, there is a possibility that the driving rib 11 is completely disengaged from the meshing groove 32 on the accumulating element 3, that is, there is a possibility that the first end is disengaged from the meshing groove 32 while the second end has not yet engaged in another meshing groove 32, in which case the accumulating element 3 remains stationary; if the driving rib 11 is set as a continuous spiral section, it is possible that the end of the driving rib 11 is not completely aligned with the meshing groove 32 when it engages in the meshing groove 32 on the accumulating element 3 again, which will cause the accumulating element 3 to rotate extra, thereby causing a cumulative error in the accumulating element 3. By adopting the above scheme, the driving rib 11 can drive the accumulating element 3 to rotate only during the driving process of the driving section 111, while the accumulating element 3 remains stationary during the meshing process and the meshing out process of the engagement section 112, which can ensure that the end of the driving rib 11 is aligned with the meshing groove 32 when it engages in the meshing groove 32 on the accumulating element 3 again, so as to avoid the situation where the accumulating element 3 rotates extra and causes a cumulative error in the accumulating element 3.

[0092] It should be noted that the total rotation angle of the first element 1 relative to the second element 2 during dose setting 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 driving rib 11 includes the driving segment 111 and the engagement segment 112, the total adjustment angle is set to an integer multiple of 360°, that is, when the maximum set dose is reached, the first element 1 rotates an integer number of turns relative to the second element 2.

[0093] Further, in some embodiments where the driving rib 11 includes a driving segment 111 and an engaging segment 112, the engaging segment 112 is configured as an arc segment arranged around the circumference of the first axis, that is, the engaging segment 112 is entirely located on a circle whose center is located on the first axis. It should be noted that the driving rib 11 includes two engaging segments 112, both of which are arc segments, but the two engaging segments 112 are located at different axial positions on the first axis.

[0094] Furthermore, in other embodiments where the driving rib 11 includes a driving segment 111 and an engagement segment 112, the driving segment 111 is configured as a spiral segment spirally arranged around a first axis; the spiral segment is used to engage with the engagement groove 32, and is used to drive the accumulation element 3 to rotate when the spiral segment rotates synchronously with the first element 1.

[0095] Further, refer to Figures 16 to 18 In some embodiments, when the first element 1 rotates one circle relative to the second element 2, the cumulative element 3 is driven to rotate the angle of one tooth; specifically, the central angle formed by the center points of two adjacent meshing grooves 32 on the cumulative element 3 relative to the second axis is defined as a reference angle a, and when the first element 1 and the second element 2 rotate one circle relative to each other, that is, 360°, the rotation angle of the cumulative element 3 is a reference angle a.

[0096] In a second aspect, an embodiment of the present application discloses an injection device that can ensure that a set dose is less than or equal to a remaining dose of a drug that can be injected, so that the actual injection dose is consistent with the set dose.

[0097] Reference Figure 1 The injection device comprises a housing 7, a clutch element 4, the dose accumulation mechanism mentioned above, a drive rod 5 and a push rod 6, wherein the clutch element 4, the dose accumulation mechanism, the drive rod 5 and the push rod 6 are all arranged in the housing 7. Moreover, during the dose setting, at least one of the first element 1 and the second element 2 can rotate relative to the clutch element 4; during the dose injection, the clutch element 4 is connected to the first element 1 and the second element 2 in a rotationally non-reversible manner in the dose injection direction. The first element 1, the second element 2, the drive rod 5 and the push rod 6 are sleeved from the outside to the inside, and at the same time, the drive rod 5 is axially fixed and rotatably arranged in the housing 7, and the drive rod 5 is rotationally non-reversibly connected to the second element 2, and the push rod 6 is threadedly connected to the drive rod 5 and forms an axial guiding fit with the housing 7, so that during the dose injection, the first element 1 drives the second element 2 and the drive rod 5 to rotate in the dose injection direction, and thereby drives the push rod 6 to feed in the axial direction. Correspondingly, the distal end of the injection device is connected to a cartridge bottle 8 containing a drug, a movable piston 81 is provided at the proximal end of the cartridge bottle 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 bottle 8 to move toward the distal end, thereby discharging the drug in the cartridge bottle 8 through the needle assembly.

[0098] Specifically, refer to Figure 1 , Figure 6 and Figure 7 , the proximal end of the second element 2 is accommodated in the proximal end of the first element 1, and at the same time, the clutch element 4 is located at the proximal end of the first element 1 and presses against the proximal end of the second element 2. At the same time, when the dose is increased, the first element 1 rotates along the third direction, and when the dose is decreased, the first element 1 rotates along the fourth direction opposite to the third direction, and when the dose is injected, the first element 1 and the second element 2 both rotate along the fourth direction. 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 first element 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 pressing against the proximal end of the second element 2.

[0099] Correspondingly, a ratchet tooth ring 12 is provided on the inner wall of the proximal end of the first element 1, and a ratchet arm 41 is provided which cooperates with the ratchet tooth ring 12. The ratchet tooth ring 12 and the ratchet arm 41 cooperate to form a first connection, which allows the first element 1 to rotate along a third direction relative to the clutch element 4, while preventing the first element 1 from rotating along a fourth direction relative to the clutch element 4.

[0100] The proximal portion of the second element 2 is provided with an axially protruding axial toothed ring 22, and the clutch element 4 is provided with matching teeth 42 meshing with the axial toothed ring 22. The axial toothed ring 22 cooperates with the matching teeth 42 under the elastic force of the spring 10 to form a second connection, and the second connection prevents the clutch element 4 from rotating in the third direction relative to the second element 2, and allows the clutch element 4 and the second element 2 to have relative axial movement so that the clutch element 4 rotates in the fourth direction relative to the second element 2. At the same time, during the dose injection, the clutch element 4 is pressed against the proximal end of the second element 2 by the axial force transmitted by the button 9, and at this time, the clutch element 4 and the second element 2 cannot have axial movement, so that the clutch element 4 and the second element 2 are relatively stationary.

[0101] Combination Fig.19 It should be noted that the axial toothed ring 22 and the mating tooth 42 are configured as inclined teeth with a cross-section similar to a right 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 toothed ring 22 abuts against the right-angled surface 421 of the mating tooth 42, the clutch element 4 is prevented from rotating along the third direction relative to the second element 2. When the inclined surface 422 of the inclined tooth on the axial toothed ring 22 abuts against the inclined surface 422 of the mating tooth 42, the clutch element 4 and the second element 2 experience relative axial movement and "tooth jumping" occurs under the elastic force of the spring 10, that is, the tooth jumps from one slot to an adjacent slot.

[0102] In summary, when the first element 1 rotates along the third direction to increase the dose, the clutch element 4 and the second element 2 remain stationary, and the first element 1 rotates relative to the second element 2 and the clutch element 4; when the first element 1 rotates along the fourth direction to decrease the dose, the first element 1 drives the clutch element 4 to rotate along the fourth direction, and the second element 2 remains stationary, and the first element 1 and the clutch element 4 rotate relative to the second element 2. During the dose injection, the first element 1, the clutch element 4 and the second element 2 rotate synchronously along the fourth direction.

[0103] 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. A dose accumulation mechanism, characterized in that: include: A first element capable of rotating about a first axis, wherein the first element is provided with a driving rib, and the driving rib extends on the first element around the first axis; A second element, which is sleeved with the first element and can rotate around the first axis; an accumulation element connected to the second element and capable of rotating relative to the second element around a second axis, the second axis being arranged crosswise with the first axis, the accumulation element being provided with a plurality of meshing teeth, the plurality of meshing teeth being arranged at intervals along the circumferential direction of the second axis, and a meshing groove for the driving rib to engage with being formed between two adjacent meshing teeth; wherein, during dose setting, the first element is capable of rotating relative to the second element in a first direction to increase the dose and in a second direction to decrease the dose, and the driving rib is used to cooperate with the meshing teeth to drive the accumulating element to rotate; During the injection of a dose, the first element is connected to the second element in a rotationally fixed manner, and the accumulating element is stationary relative to the first element and the second element; The accumulating element has a starting position and an ending position, the movement stroke of the accumulating element between the starting position and the ending position corresponds to the total amount of medicine that can be injected by the injection device, and when the accumulating element is in the ending position, the first element is restricted from further rotating relative to the second element in the first direction.

2. The dose accumulation mechanism according to claim 1, characterized in that: The first element is provided with a first stopper, which moves with the first element around the first axis, and the accumulating element is provided with a second stopper, which moves with the accumulating element around the second axis; when the first stopper abuts against the second stopper, the starting position or the ending position is formed.

3. The dose accumulation mechanism according to claim 2, characterized in that: The starting position or the ending position is formed when the second stopping portion blocks the first stopping portion from continuing to move around the first axis.

4. The dose accumulation mechanism according to claim 3, characterized in that: The first stop portion includes a first starting portion, and the second stop portion includes a second starting portion; the movement direction of the first starting portion when reducing the dose is defined as a starting approach direction, and the starting position of the accumulating element is formed when the second starting portion moves to block the first starting portion from continuing to move along the starting approach direction.

5. The dose accumulation mechanism according to claim 4, characterized in that: The first starting portion is configured as an end portion of the driving rib.

6. The dosage accumulation mechanism according to claim 4 or 5, characterized in that: The second starting portion is arranged between two adjacent meshing teeth.

7. The dose accumulation mechanism according to claim 3, characterized in that: The first stop portion includes a first stop portion, and the second stop portion includes a second stop portion; the movement direction of the first stop portion when increasing the dose is defined as a stop approach direction, and the stop position of the accumulation element is formed when the second stop portion moves to block the first stop portion from continuing to move along the stop approach direction.

8. The dose accumulation mechanism according to claim 7, characterized in that: The first end portion is configured as an end portion of the driving rib.

9. The dosage accumulation mechanism according to claim 7 or 8, characterized in that: The second terminating portion is disposed between two adjacent meshing teeth.

10. The dose accumulation mechanism according to claim 1, 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 or equal to 360°.

11. The dose accumulation mechanism according to claim 10, 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 second element remain relatively stationary.

12. The dose accumulation mechanism according to claim 11, characterized in that: The drive segment is configured as a helical segment helically disposed about the first axis.

13. The dose accumulation mechanism according to claim 1, characterized in that: The central angle between the center points of two adjacent meshing grooves on the accumulating element and the second axis is defined as a reference angle. When the first element and the second element rotate 360° relative to each other, the rotation angle of the accumulating element is a reference angle.

14. The dose accumulation mechanism according to claim 1, characterized in that: The first element is sleeved outside the second element, the driving rib is arranged on the inner side wall of the first element, and the second element is provided with an escape area for the accumulating element to rotate.

15. The dose accumulation mechanism according to claim 1, characterized in that: The second element is sleeved outside the first element, the driving rib is arranged on the outer side wall of the first element, and an active cavity for the accumulating element to rotate is formed between the first element and the second element.

16. An injection device, characterized in that: A dose accumulation mechanism comprising a clutch element and any one of claims 1 to 15, wherein during dose setting, at least one of the first element and the second element is capable of rotating relative to the clutch element; During dosage injection, the clutch element is connected to the first element and the second element in a rotationally fixed manner in the dosage injection direction.

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