CN117919549A - Dose adjusting mechanism and injection device - Google Patents

Abstract

The invention discloses a dose regulating mechanism and an injection device, comprising a first shell, a scale drum, a main driving shaft and a knob, wherein: the side wall of the first shell is provided with a first elastic arm and an outer bulge, and the first shell is provided with an observation port; the main driving shaft is arranged on the inner side of the first shell; the scale drum is arranged on the outer side of the main driving shaft and the inner side of the first shell, is fixedly arranged in the circumferential direction of the main driving shaft and axially slides, and is in threaded connection with the first shell; the knob is rotationally connected with the first shell and fixedly arranged along the circumferential direction of the main driving shaft; the knob enables the first elastic arm to elastically deform inwards from an initial state to a locking state; when the first elastic arm is in a locking state, the limiting end of the first elastic arm can prop against the stopping end of the scale drum, so that the injection device can be accurately adjusted to the maximum injection quantity.

Description

Dose adjusting mechanism and injection device

Technical Field

The invention relates to the technical field of medicine injection, in particular to a dose adjusting mechanism and an injection device.

Background

During the course of treatment, part of the drug may be injected into the human body using an injection device, such as semaglutin for diabetes.

In the related art, the injection device comprises a shell, a scale drum and a driving drum, wherein the shell, the scale drum and the driving drum are arranged with a central shaft, the scale drum is arranged on the inner side of the shell and is positioned on the outer side of the driving drum, the inner wall of the scale drum and the outer wall of the driving drum are axially and slidably arranged, the circumference is fixed, the outer wall of the scale drum is in threaded connection with the inner wall of the shell, and the side wall of the shell is provided with an observation port for displaying the scale marks of the scale drum. In the process of adjusting the scale drum, the driving drum drives the scale drum to synchronously rotate, and the scale drum is in threaded connection with the shell, so that the scale drum slides along the axial direction of the shell in the rotating process, and the scales displayed on the observation port are adjusted.

By adopting the injection device with the structural form, when the zero scale mark of the scale drum is adjusted to the observation port, the end part of the scale drum is propped against the circumference of the driving drum, so that excessive adjustment of the scale drum is limited. However, because there is an error between the scale drum or the driving drum, when the end of the scale drum is abutted against the circumferential direction of the driving drum, the position error of the zero scale mark of the scale drum from the observation port is large.

Disclosure of Invention

In order to solve at least one of the problems in the prior art, the invention discloses a dose adjusting mechanism and an injection device, which can ensure the accuracy of the initial position of a scale drum.

In a first aspect, the application discloses a dose adjustment mechanism comprising a first housing, a scale drum, a main drive shaft and a knob, wherein:

The side wall of the first shell is provided with a first elastic arm extending in the circumferential direction and an outer protrusion arranged on the outer wall of the first elastic arm, and the side wall of the first shell is provided with an observation port;

the main driving shaft is at least partially arranged on the inner side of the first shell and is arranged with the central shaft;

The scale drum is arranged on the outer side of the main driving shaft and the inner side of the first shell, is arranged with the central shaft, is fixedly arranged with the main driving shaft in the circumferential direction and axially slides, is in threaded connection with the first shell, and is used for displaying scale marks of the scale drum;

the knob is rotationally connected with the first shell and fixedly arranged along the circumferential direction of the main driving shaft;

The scale drum is provided with a circumferentially-oriented stop end, the first elastic arm is provided with a circumferentially-oriented limit end, and the inner wall of the knob is propped against the outer protrusion so that the first elastic arm elastically deforms inwards from an initial state to a locking state; when the first elastic arm is in a locking state, the limiting end can abut against the stopping end.

In one possible embodiment, one of the outer wall of the first housing and the inner wall of the knob is provided with an annular protrusion, and the other is provided with an annular groove, and the annular protrusion is rotationally embedded in the annular groove.

In one possible embodiment, the graduation marks of the graduation drum have zero graduation marks and preset graduation marks;

The end of the scale drum, which is close to the preset scale mark, is provided with a second elastic arm and a positioning protrusion, and the inner wall of the first shell is provided with a stop position, wherein when the zero scale mark is at the observation port, the positioning protrusion is clamped at the stop position.

In one possible embodiment, the positioning projection is axially projecting.

In one possible embodiment, the inner wall of the first housing is provided with a clamping protrusion to form the stop position, and the positioning protrusion is embedded in the stop position to be clamped with the clamping protrusion.

In one possible embodiment, the side of the locking projection facing away from the stop position has a first stop surface facing circumferentially, and the end of the scale drum is provided with a second stop surface, wherein the first stop surface abuts against the second stop surface when the zero graduation mark is at the viewing port.

In a possible embodiment, the dose adjustment mechanism further comprises a drive barrel arranged outside the main drive shaft and inside the scale barrel and arranged concentrically with the central axis;

The inner side of the driving cylinder is circumferentially fixed with the main driving shaft, the outer side of the driving cylinder is circumferentially fixed with the scale cylinder and axially slides, and an accommodating gap is formed between the driving cylinder and the main driving shaft.

In one possible embodiment, the first housing includes an inner housing, an outer housing, and a connection portion, wherein;

the outer shell is provided with the first elastic arm, the knob is rotatably arranged on the outer shell, the outer shell is provided with the observation port, and the scale drum is in threaded connection with the outer shell;

The inner shell is arranged on the inner side of the outer shell and is arranged with the central shaft, and the main driving shaft is arranged on the inner side of the inner shell;

The driving cylinder is rotationally sleeved on the outer side of the inner shell, an extension part is arranged at the end part of the driving cylinder, and the extension part and the main driving shaft are fixedly arranged in the circumferential direction;

the connecting portion is connected with the inner shell and the outer shell.

In one possible embodiment, the dose adjustment mechanism further comprises a torsion spring and clutch assembly comprising:

the torsion spring is sleeved on the outer side of the main driving shaft, one end of the torsion spring is connected with the first shell, and the other end of the torsion spring is connected with the main driving shaft;

The clutch assembly is configured to maintain the torsion spring in a twisted state by the main drive shaft and to release the twisted state of the torsion spring.

In a second aspect, the present application discloses an injection device comprising:

the dose setting mechanism described above;

the pushing equipment comprises a second shell, a push rod, a locking seat, a rotating seat and a fixing seat, wherein:

The fixed seat is connected with the first shell;

the second shell is connected with the fixed seat and is used for loading a drug carrier;

the push rod is in threaded connection with the fixed seat and is used for acting on the tail part of the drug carrier;

The rotating seat is rotationally arranged on the fixed seat, the main driving shaft is provided with a first driving tooth part, the rotating seat is provided with a second driving tooth part and is used for meshing with the first driving tooth part, and the push rod axially slides with the rotating seat and is circumferentially fixedly arranged;

the locking seat is connected to the fixing seat and used for enabling the rotating seat to be kept on the fixing seat.

From the above technical solutions, the embodiment of the present application has the following advantages: the application adopts the first elastic arm and the screw thread to be integrated on the first shell at the same time, thereby ensuring the accuracy of the first elastic arm, further ensuring that the maximum scale mark of the scale drum just aligns with the corresponding position of the observation port when the stop end of the scale drum is propped against the stop end of the first elastic arm, and further ensuring the setting of the maximum injection quantity of the injection device.

Drawings

FIG. 1 is a schematic view of a partially exploded construction of a dose-setting mechanism according to an embodiment of the present invention;

FIG. 2 is a schematic view of a scale drum according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating an assembly of a scale drum and a first housing according to an embodiment of the present invention;

FIG. 4 is a cross-sectional view of a scale drum and a first housing according to an embodiment of the present invention;

Fig. 5 is an axial cross-sectional view of a dose-adjusting mechanism according to an embodiment of the invention;

FIG. 6 is a schematic view of an assembled structure of a main drive shaft, torsion spring and clutch assembly according to an embodiment of the present invention;

FIG. 7 is a schematic view of an exploded view of a main drive shaft and clutch assembly according to an embodiment of the present invention;

fig. 8 is a schematic structural view of a clutch gear sleeve in a clutch assembly according to an embodiment of the invention.

FIG. 9 is a schematic view of a part of an exploded structure of a pushing mechanism according to an embodiment of the present invention;

fig. 10 is a schematic view showing the overall structure of an injection device according to an embodiment of the present invention.

Wherein the reference numerals have the following meanings:

100. A dose adjustment mechanism; 110. a first housing; 111. an inner housing; 112. an outer housing; 1121. an annular convex edge; 1122. the clamping bulge; 1123. a first stop surface; 1124. a stop position; 1125. an observation port; 113. a connection part; 1131. a first circumferential positioning portion; 114. a first elastic arm; 1141. an outer protrusion; 1142. a limiting end; 120. a knob; 121. an annular groove; 130. a scale drum; 131. a second elastic arm; 132. positioning the bulge; 133. a second stop surface; 134. zero scale mark; 135. presetting scale marks; 136. a stop end; 140. a drive cylinder; 141. an extension; 150. a main drive shaft; 151. a first drive tooth portion; 152. a first clutch tooth portion; 160. a clutch assembly; 161. a clutch gear shaft; 1611. a second clutch tooth portion; 1612. a clutch arm; 1613. clutch protrusions; 162. clutch gear sleeve; 1621. a clutch groove; 1622. a second circumferential positioning portion; 163. a connection cover; 164. a spring; 170. a torsion spring; 180. a button; 200. a pushing mechanism; 210 a second housing; 211. a drug carrier; 220. a push rod; 230. a locking seat; 231. a locking groove; 240. a rotating seat; 241. a locking arm; 242. a locking protrusion; 243. a second drive tooth portion; 250. a fixing seat.

Detailed Description

For a better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The invention is described in further detail below with reference to the accompanying drawings.

Referring to fig. 1 to 3, the dose adjusting mechanism 100 of the present application includes a first housing 110, a scale drum 130, a main driving shaft 150, and a knob 120, wherein: the side wall of the first shell 110 is provided with a first elastic arm 114 extending in the circumferential direction and an outer protrusion 1141 arranged on the outer wall of the first elastic arm 114, and the side wall of the first shell 110 is provided with an observation port 1125; the main driving shaft 150 is at least partially disposed inside the first housing 110 and is disposed with the central axis; the scale drum 130 is disposed on the outer side of the main driving shaft 150 and the inner side of the first housing 110, and is disposed on the same central axis, the scale drum 130 is fixedly disposed on the circumference of the main driving shaft 150 and is axially slidably disposed, the scale drum 130 is in threaded connection with the first housing 110, and the observation port 1125 is used for displaying scale marks of the scale drum 130; the knob 120 is rotatably connected with the first housing 110 and fixedly arranged along the circumferential direction of the main driving shaft 150; the scale drum 130 has a circumferentially-oriented stop end 136, the first elastic arm 114 has a circumferentially-oriented limit end 1142, and the inner wall of the knob 120 abuts against the outer protrusion 1141, so that the first elastic arm 114 elastically deforms inwards from an initial state to a locking state; when the first elastic arm 114 is in the locked state, the limiting end 1142 can abut against the stopping end 136.

Specifically, during the dose adjustment phase, the zero graduation marks 134 of the graduation drum 130 are positioned at the viewing port 1125, and the healthcare worker rotates the main drive shaft 150 in a forward direction, and the main drive shaft 150 drives the graduation drum 130 to rotate in a synchronous forward direction. Since the inner side of the scale drum 130 is axially slidably disposed with the main driving shaft 150, the outer side of the scale drum 130 is threadedly connected with the first housing 110, so that the main driving shaft 150 drives the scale drum 130 to rotate in the forward direction, and the scale drum 130 slides backward along the axial direction of the first housing 110. The observation port 1125 is used for observing the adjustment condition of the dose, and the larger the dose adjustment is, the larger the scale value of the scale line corresponding to the observation port 1125 is. When the medical staff observes that the scale value at the observation port 1125 reaches the maximum scale value, for example, 80UI of the scale drum 130, the stop end 136 of the scale drum 130 abuts against the stop end 1142 of the first elastic arm 114, the scale drum 130 stops rotating, and the injection dosage of the injection device is just adjusted to the maximum injection dosage. In the medicine injection stage, the main driving shaft 150 rotates reversely, the main driving shaft 150 drives the scale drum 130 to synchronously rotate reversely, the scale drum 130 moves axially backwards, the observation port 1125 is used for observing the injection condition of medicine, and when the observation port 1125 displays zero scale mark 134, the injection device just injects the preset medicine amount.

As can be seen from the above, the limiting end 1142 of the first elastic arm 114 abuts against the stopping end 136 of the scale drum 130 when the scale drum 130 is adjusted to the maximum dose, and the scale drum 130 cannot rotate forward. It can be seen that by the arrangement of the first resilient arm 114, a medical person can conveniently and accurately adjust the injection volume of the injection device to the maximum injection volume.

Wherein, the inner wall of the first housing 110 is integrated with screw threads to be screwed with the scale drum 130. Compared with the driving barrel 140 with the limit end 1142 integrated in the application in the prior art, the application adopts the first elastic arm 114 and the screw thread to be integrated in the first shell 110 at the same time, thereby ensuring the accuracy of the first elastic arm 114, further ensuring that the maximum scale mark of the scale barrel 130 just aligns with the position corresponding to the observation port 1125 when the limit end 136 of the scale barrel 130 abuts against the limit end 1142 of the first elastic arm 114, and further ensuring the setting of the maximum injection amount of the injection device.

In addition, when the scale drum 130 is manufactured, the first elastic arm 114 is in an initial state and does not protrude toward the inner side of the first housing 110, and the first elastic arm 114 does not interfere with the formation of the screw teeth, thereby ensuring that the first housing 110 can be manufactured more conveniently.

It is understood that the first elastic arm 114 extends circumferentially around the central axis, and the first elastic arm 114 may extend circumferentially in a forward direction or extend circumferentially in a reverse direction, and the outer protrusion 1141 is disposed at the limiting end 1142 of the first elastic arm 114. The first elastic arm 114 is so arranged, and the elastic performance of the first elastic arm 114 is good, so that medical staff can better elastically deform and cannot be damaged easily in the process of rotating the knob 120.

In order to realize the rotary connection between the knob 120 and the first housing 110, in a specific embodiment, an annular flange 1121 is disposed on the peripheral surface of the rear end portion of the first housing 110, an annular groove 121 is disposed on the inner peripheral surface of the knob 120, and the annular flange 1121 is rotationally embedded in the annular groove 121, so that the knob 120 is rotationally disposed on the rear end portion of the first housing 110. Or the inner circumferential surface of the knob 120 is provided with an annular flange 1121, the outer circumferential surface of the rear end portion of the first housing 110 is provided with an annular groove 121, and the annular flange 1121 is rotatably embedded in the annular groove 121.

In some embodiments, referring to fig. 2 and 4, the graduation marks of the graduation drum 130 have zero graduation marks 134 and preset graduation marks 135, and the zero graduation marks 134 are disposed near the rear end of the graduation drum 130, and the preset graduation marks 135 are disposed near the front end of the graduation drum 130. The front end of the scale drum 130 is provided with a first elastic arm 114, the first elastic arm 114 is spirally extended with a central shaft, and a limiting end 1142 of the first elastic arm 114 is provided with a positioning protrusion 132; meanwhile, the inner wall of the first housing 110 is provided with a stop position 1124, and the positioning protrusion 132 is used for being clamped at the stop position 1124.

In particular implementations, the first resilient arm 114 allows the positioning protrusion 132 to nest in the stop 1124 before the dose is not adjusted by the injection device, thereby ensuring that the zero graduation mark 134 is always aligned with the viewing port 1125 for subsequent accurate dose adjustment; in the process of injecting the medicine, the zero graduation marks 134 of the graduation drum 130 can collide with the first housing 110 when moving to the observation port 1125, and the first housing 110 vibrates or generates collision sound to remind medical staff that the medicine injection is completed by the injection device.

Wherein, the positioning protrusion 132 is disposed with the axial forward protrusion, and the stop position 1124 is disposed with the axial backward protrusion, and the positioning protrusion 132 is axially embedded in the stop position 1124. It can be appreciated that, compared to the radially outward projection 1141 of the positioning projection 132, the positioning projection 132 is axially projected, the positioning projection 132 does not increase the thickness of the scale drum 130, and the scale drum 130 does not rub against the inner wall of the first housing 110 during rotation and axial movement, so that smooth rotation and axial movement of the scale drum 130 is ensured. As such, the scale drum 130 and the first housing 110 can be assembled more compactly, and the accuracy can be set higher.

Further, the inner wall of the first housing 110 is provided with a locking protrusion 1122, the locking protrusion 1122 is located at the inner side of the front end of the first housing 110, one side of the locking protrusion 1122 forms a stop 1124 with an opening facing the rear side, and the positioning protrusion 132 is locked to the locking protrusion 1122. During injection of the drug, the zero graduation marks 134 of the graduation drum 130 are positioned near the viewing port 1125, and the positioning projections 132 are positioned near the stopping positions 1124, the engaging projections 1122 act on the second elastic arms 131 via the positioning projections 132, and the second elastic arms 131 are deformed rearward. When the locking protrusion 1122 moves to the locking position 1124, the second elastic arm 131 returns the positioning protrusion 132 to the initial position, and the positioning protrusion 132 is embedded in the locking position 1124 and is circumferentially locked with the locking protrusion 1122. It can be appreciated that, by the arrangement of the clamping projection 1122, the second elastic arm 131 can be elastically deformed backward in a larger radian by the clamping projection 1122, so that the positioning projection 132 can act on the first housing 110 to a larger extent when the positioning projection is reset, so that the housing generates a large enough collision sound or vibration to reflect that the medical staff has completed the drug injection.

Of course, instead of the engaging projection 1122, the stop 1124 may be a slot provided in the connecting portion 113, and the positioning projection 132 is engaged with the slot.

Further, the side of the engaging projection 1122 away from the stop position 1124 has a first stop surface 1123 facing circumferentially, the front end of the scale drum 130 has a second stop surface 133 facing circumferentially, and the first stop surface 1123 is disposed opposite the second stop surface 133. Specifically, during injection of the injection device, when the zero graduation marks 134 of the graduation drum 130 are at the observation port 1125, the first stop surface 1123 abuts against the second stop surface 133, and the injection device stops injecting the medicine into the human body, thereby preventing the injection device from excessively injecting the medicine.

In some embodiments, referring to fig. 1 and 5, the dose adjusting mechanism 100 further includes a driving barrel 140, where the driving barrel 140 is disposed outside the main driving shaft 150 and inside the scale barrel 130, and is disposed with the central axis, the driving barrel 140 is fixedly disposed circumferentially with the main driving shaft 150, and is axially slidably disposed, and the inner circumferential surface of the scale barrel 130 is fixedly disposed circumferentially with the outer circumferential surface of the driving barrel 140, and is axially slidably disposed. Specifically, the healthcare worker rotates the knob 120 forward and backward, the knob 120 drives the main driving shaft 150 to rotate synchronously, the main driving shaft 150 drives the driving barrel 140 to rotate synchronously, and the driving barrel 140 drives the scale barrel 130 to rotate. Since the scale drum 130 is screwed to the first housing 110, the scale drum 130 moves circumferentially when the drive drum 140 drives the scale drum 130 to rotate, and the scale marks of the scale drum 130 at the observation port 1125 change sequentially.

It can be appreciated that, by the arrangement of the driving barrel 140, the driving force of the main driving shaft 150 can drive the scale drum 130 to rotate and axially slide through the driving barrel 140, so as to adjust the scale mark of the scale drum 130 at the observation port 1125.

Wherein, an accommodation space can be formed between the driving cylinder 140 and the main driving shaft 150, and the accommodation space can be used for accommodating the torsion spring 170, so as to prevent the scale drum 130 from interfering with the torsion spring 170 when moving axially.

Of course, instead of the arrangement of the drive cylinder 140, the scale drum 130 may be arranged directly axially fixed to the main drive shaft 150, as well as axially slidable. Thus, the knob 120 drives the main drive shaft 150 to rotate synchronously, and the main drive shaft 150 directly drives the scale drum 130 to rotate, thereby controlling the scale drum 130 to move axially simultaneously.

Further, the first housing 110 includes an inner housing 111, an outer housing 112, and a connection portion 113, the inner housing 111 is disposed inside the outer housing 112 and is disposed concentrically with the outer housing, the connection portion 113 is connected to a front end portion of the inner housing 111, and is connected to an inner wall of the outer housing 112; the observation port 1125 is provided in the outer case 112, the knob 120 is rotatably provided at a rear end portion of the outer case 112, and the first elastic arm 114 is provided at a rear end portion of the outer case 112.

The driving cylinder 140 is rotatably sleeved outside the inner casing 111, and an L-shaped extension 141 is provided at the rear end of the driving cylinder 140. The extension portion 141 is sleeved on the rear end portion of the main driving shaft 150, and the extension portion 141 is fixedly disposed circumferentially with the main driving shaft 150 and axially slides.

It will be appreciated that the first housing 110 adopting the above-described structural form, that is, the driving cylinder 140 can be stably rotatably fitted inside the first housing 110 by the arrangement of the inner housing 11.

In some embodiments, referring to fig. 6 to 8, the front end portion of the main driving shaft 150 is sequentially provided with a plurality of first driving teeth 151 spaced around the central shaft. The main driving shaft 150 is axially slidable to switch between a first position and a second position, when the main driving shaft 150 is in the first position, the first driving teeth 151 of the main driving shaft 150 are separated from the corresponding members, and the main driving shaft 150 does not drive the corresponding members to rotate; when the main drive shaft 150 is in the second position, the main drive shaft 150 is configured to rotate via the first drive teeth 151 to drive a member that interfaces with the first drive teeth 151.

Further, the dose adjusting mechanism 100 further includes a torsion spring 170, the torsion spring 170 is sleeved on the main driving shaft 150, the front end of the torsion spring 170 is connected to the front end of the main driving shaft 150, and the rear end is connected to the first housing 110. Specifically, the main drive shaft 150 is rotated a set number of turns before the injection device is used, and the torsion spring 170 receives an elastic force. When the injection device is required to inject the medicine, the torsion force of the torsion spring 170 is released, and the torsion spring 170 drives the main drive shaft 150 to reversely rotate, thereby powering the corresponding components.

Still further, the dose-adjusting mechanism 100 further comprises a clutch assembly 160, the clutch assembly 160 being connected to the main drive shaft 150 for maintaining the torsion spring 170 in a stored-force state by the main drive shaft 150. Specifically, after the main drive shaft 150 rotates in the forward direction for a plurality of rotations, the clutch assembly 160 restricts the main drive shaft 150 from rotating in the reverse direction, so that the main drive shaft 150 maintains the rotated position, and at this time, the torsion spring 170 is in a power storage state. When the main drive shaft 150 is drivingly connected to the propeller shaft, the clutch assembly 160 releases the restriction of the main drive shaft 150, and the main drive shaft 150 is rotationally moved by the torsion spring 170, thereby powering the main drive shaft 150.

The clutch assembly 160 includes a clutch gear sleeve 162, a clutch gear 161 and a spring 164, wherein the clutch gear sleeve 162 is disposed on the outer side of the main driving shaft 150 and the inner side of the first housing 110, and is disposed coaxially with the main driving shaft 150. The clutch gear 161 is disposed on the outside of the main drive shaft 150 and on the inside of the clutch gear sleeve 162, and is disposed coaxially with the main drive shaft 150. Wherein, the side part of the clutch gear shaft 161 is provided with a clutch arm 1612 in a circumferential extension way, and the end part of the clutch arm 1612 is provided with a clutch protrusion 1613; meanwhile, the clutch tooth sleeve 162 is sequentially provided with clutch grooves 1621 at intervals around the central shaft, the clutch grooves 1621 extend in the axial direction, and the clutch protrusions 1613 are embedded in the clutch grooves 1621 and can axially slide along the clutch grooves 1621. Meanwhile, the side portion of the front end portion of the main drive shaft 150 is provided with first clutch teeth 152 facing rearward at intervals in order around the central axis, the front end portion of the clutch teeth shaft 161 is provided with second clutch teeth 1611 facing forward at intervals around the central axis, and the first clutch teeth 152 are engaged with the second clutch teeth 1611. The spring 164 is abutted between the clutch gear sleeve 162 and the clutch gear shaft 161, and the spring 164 keeps the second clutch gear 1611 engaged with the first clutch gear 152. The resistance of the clutch protrusion 1613 and the clutch groove 1621 in the first circumferential direction is greater than the resistance of the first clutch tooth 152 and the second clutch tooth 1611 in the first circumferential direction, and the resistance of the clutch protrusion 1613 and the clutch groove 1621 in the second circumferential direction is smaller than the resistance of the first clutch tooth 152 and the second clutch tooth 1611 in the second circumferential direction, and the first circumferential direction and the second circumferential direction are opposite, and the second circumferential direction is the torsion direction of the torsion spring 170.

Specifically, the main drive shaft 150 performs a forward rotational motion against the circumferential elastic force of the torsion spring 170 and the circumferential resistance of the second clutch teeth 1611 to the first clutch teeth 152. Because the resistance of the clutch protrusion 1613 and the clutch groove 1621 in the forward direction is greater than the resistance of the first clutch tooth 152 and the second clutch tooth 1611 in the forward direction, the resistance of the clutch sleeve 162 to the clutch tooth 161 in the forward direction is greater during the forward rotation of the main drive shaft 150, the clutch tooth 161 slides axially, and the clutch protrusion 1613 slides axially along the clutch groove 1621 and does not rotate forward with the main drive shaft 150. When the main drive shaft 150 is rotated, the main drive shaft 150 stops rotating, the clutch gear 161 is engaged with the first clutch gear 152 by the spring 164, the main drive shaft 150 is maintained at the rotated position, and the torsion spring 170 maintains the torsion state. If the main drive shaft 150 rotates too much in the forward direction, the main drive shaft 150 is controlled to perform reverse rotational movement. Because the resistance of the clutch protrusion 1613 and the clutch groove 1621 in the reverse direction is smaller than the resistance of the first clutch tooth 152 and the second clutch tooth 1611 in the reverse direction, the clutch tooth 161 and the main driving shaft 150 synchronously rotate in the reverse direction during the reverse rotation of the main driving shaft 150, the clutch arm 1612 is elastically deformed inwards, and the clutch protrusion 1613 sequentially jumps in the clutch groove 1621. When the main drive shaft 150 is reversely rotated to a proper position, the clutch arm 1612 engages the clutch protrusion 1613 in the corresponding clutch groove 1621, and thus, the clutch gear shaft 161 holds the main drive shaft 150 in a rotated position, and the torsion spring 170 is in a torsion state.

Further, the clutch assembly 160 further includes a connection cover 163, the connection cover 163 is connected to the clutch gear sleeve 162 and the main driving shaft 150, the connection cover 163 connects the main driving shaft 150 to the clutch gear sleeve 162, and the spring 164 is abutted between the clutch gear shaft 161 and the clutch gear sleeve 162. It will be appreciated that the various components of the clutch assembly 160 may be assembled as a single unit to facilitate subsequent assembly within the first housing 110. The connecting cover 163 is at least rotatably connected with the clutch gear sleeve 162 or the main driving shaft 150, and the clutch gear sleeve 162 is rotatably connected with the main driving shaft 150, so that the clutch gear shaft 161 does not interfere with the normal rotation of the main driving shaft 150, and the normal use of each component of the clutch assembly 160 is ensured.

Further, the front side surface of the connecting portion 113 is provided with first circumferential positioning portions 1131 (see fig. 4) at intervals around the central axis, and the first circumferential positioning portions 1131 are provided to extend axially; meanwhile, the clutch gear sleeve 162 is provided with a plurality of second circumferential positioning portions 1622 around the central shaft at intervals, and the second circumferential positioning portions 1622 are axially extended. The first circumferential positioning portions 1131 and the second circumferential positioning portions 1622 are sequentially staggered around the circumferential direction, so that the first circumferential positioning portions 1131 and the second circumferential positioning portions 1622 are circumferentially clamped to enable the clutch gear sleeve 162 to be circumferentially fixed to the first housing 110 and axially slidable. Specifically, the main drive shaft 150 is axially slidable to transition between a first position and a second position. When the main driving shaft 150 is at the first position, the second circumferential positioning portion 1622 engages with the first circumferential positioning portion 1131, and the clutch gear sleeve 162 remains circumferentially stationary during rotation of the main driving shaft 150, so as to ensure that the clutch gear shaft 161 is circumferentially stationary, and therefore, the clutch gear shaft 161 can engage with the second clutch gear portion 1611 through the first clutch gear portion 152 to prevent the main driving shaft 150 from rotating reversely, and the torsion spring 170 is in a torsion state. When the main driving shaft 150 moves axially from the first position to the second position, the second circumferential positioning portion 1622 is just separated from the first circumferential positioning portion 1131, the first driving tooth portion 151 of the main driving shaft 150 is in driving connection with a corresponding member (a rotation ratio described below), and at this time, the first housing 110 releases the restriction of the clutch assembly 160, and the torsion spring 170 can drive the main driving shaft 150 to rotate reversely.

The application discloses an injection device, referring to fig. 9 and 10, comprising a dose adjusting mechanism 100 and a pushing mechanism 200, wherein the pushing mechanism 200 comprises a second housing 210, a push rod 220, a locking seat 230, a rotating seat 240 and a fixing seat 250, wherein: the fixing base 250 is connected with the first housing 110; the second housing 210 is connected to the holder 250 for loading the drug carrier 211; the push rod 220 is in threaded connection with the fixing seat 250 and is used for acting on the tail part of the medicine carrier 211; the rotating seat 240 is rotatably disposed on the fixing seat 250, the main driving shaft 150 has a first driving tooth portion 151, the rotating seat 240 has a second driving tooth portion 243, and is used for meshing with the first driving tooth portion 151, and the push rod 220 and the rotating seat 240 axially slide and are fixedly disposed in a circumferential direction; the locking seat 230 is connected to the fixing seat 250 for maintaining the rotating seat 240 to the fixing seat 250.

Specifically, by pressing the button 180 at the rear end of the main drive shaft 150, the main drive shaft 150 moves axially forward, the second circumferential positioning portion 1622 moves axially forward relative to the first circumferential positioning portion 1131, and the first driving teeth 151 are engaged with the second driving teeth 243; meanwhile, the first housing 110 releases the restriction of the clutch assembly 160, and the torsion spring 170 drives the main driving shaft 150 to rotate reversely, and the main driving shaft 150 drives the rotating member to rotate synchronously. Because the main driving shaft 150 and the rotating seat 240 are axially and slidably arranged and circumferentially fixed, the main driving shaft 150 drives the push rod 220 to rotate in a synchronous direction through the rotating seat 240. Since the push rod 220 is screw-coupled with the fixing base 250, the push rod 220 moves axially forward when the push rod 220 rotates in synchronization with the rotating base 240, thereby acting on the tail of the medicine carrier 211, and the medicine in the medicine carrier 211 is injected into the human body through the needle structure at the front end of the second housing 210. When the forward pressing of the main drive shaft 150 is stopped, the main drive shaft 150 moves rearward by the torsion spring 170, the first driving teeth 151 are separated from the second driving teeth 243, and the push rod 220 stops the forward acting of the medicine carrier 211, thereby causing the injection device to rapidly stop injecting medicine into the human body.

Further, the side wall of the rotating seat 240 is provided with a locking arm 241 extending circumferentially, the locking arm 241 is elastically deformable radially inwards, and the outer wall of the movable end of the locking arm 241 is provided with a locking protrusion 242; meanwhile, a locking groove 231 is formed around the central axis at the inner side of the locking seat 230, and a locking protrusion 242 is embedded in the locking groove 231, wherein the locking protrusion 242 can be clamped in different locking grooves 231 when the rotating seat 240 rotates. Specifically, during the drug injection stage, the main driving shaft 150 drives the rotating seat 240 to rotate in the opposite direction in synchronization, the rotating seat 240 drives the push rod 220 to rotate in synchronization, and the push rod 220 moves axially forward, thereby acting on the tail of the drug carrier 211 to complete drug injection; meanwhile, the locking arm 241 and the locking protrusion 242 also rotate along with the circumference in the rotating process of the rotating seat 240, the locking arm 241 is elastically deformed, and the locking protrusion 242 sequentially jumps into each locking groove 231, so that the injection device sounds and/or generates tiny vibration in the injection process, and medical staff is reminded of normally injecting medicine into a human body.

The technical means disclosed by the scheme of the invention is not limited to the technical means disclosed by the embodiment, and also comprises the technical scheme formed by any combination of the technical features. It should be noted that modifications and adaptations to the invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.

Claims (10)

1. A dose adjustment mechanism comprising a first housing, a scale drum, a main drive shaft and a knob, wherein:

The side wall of the first shell is provided with a first elastic arm extending in the circumferential direction and an outer protrusion arranged on the outer wall of the first elastic arm, and the side wall of the first shell is provided with an observation port;

the main driving shaft is at least partially arranged on the inner side of the first shell and is arranged with the central shaft;

The scale drum is arranged on the outer side of the main driving shaft and the inner side of the first shell, is arranged with the central shaft, is fixedly arranged with the main driving shaft in the circumferential direction and axially slides, is in threaded connection with the first shell, and is used for displaying scale marks of the scale drum;

the knob is rotationally connected with the first shell and fixedly arranged along the circumferential direction of the main driving shaft;

The scale drum is provided with a circumferentially-oriented stop end, the first elastic arm is provided with a circumferentially-oriented limit end, and the inner wall of the knob is propped against the outer protrusion so that the first elastic arm elastically deforms inwards from an initial state to a locking state; when the first elastic arm is in a locking state, the limiting end can abut against the stopping end.

2. A dose setting mechanism as defined in claim 1, wherein one of the outer wall of said first housing and the inner wall of said knob is provided with an annular projection and the other is provided with an annular groove, said annular projection being rotatably nested in said annular groove.

3. A dose setting mechanism as defined in claim 1, wherein the graduation marks of the graduated cylinder have zero graduation marks and predetermined graduation marks;

The end of the scale drum, which is close to the preset scale mark, is provided with a second elastic arm and a positioning protrusion, and the inner wall of the first shell is provided with a stop position, wherein when the zero scale mark is at the observation port, the positioning protrusion is clamped at the stop position.

4. A dose setting mechanism as defined in claim 3, wherein said positioning boss is axially protruding.

5. A dose setting mechanism as defined in claim 4, wherein the inner wall of said first housing is provided with a snap-fit projection to form said stop location, said positioning projection being embedded in said stop location to snap-fit with said snap-fit projection.

6. A dose setting mechanism as claimed in claim 5, wherein the side of the snap projection remote from the stop position has a first stop surface facing circumferentially, the end of the scale drum being provided with a second stop surface, wherein the first stop surface abuts the second stop surface when the zero graduation mark is at the viewing aperture.

7. A dose setting mechanism as claimed in claim 1, further comprising a drive barrel disposed outside the main drive shaft and inside the scale barrel and concentric therewith;

The inner side of the driving cylinder is circumferentially fixed with the main driving shaft, the outer side of the driving cylinder is circumferentially fixed with the scale cylinder and axially slides, and an accommodating gap is formed between the driving cylinder and the main driving shaft.

8. A dose setting mechanism as defined in claim 7, wherein said first housing comprises an inner housing, an outer housing and a connecting portion, wherein;

the outer shell is provided with the first elastic arm, the knob is rotatably arranged on the outer shell, the outer shell is provided with the observation port, and the scale drum is in threaded connection with the outer shell;

The inner shell is arranged on the inner side of the outer shell and is arranged with the central shaft, and the main driving shaft is arranged on the inner side of the inner shell;

The driving cylinder is rotationally sleeved on the outer side of the inner shell, an extension part is arranged at the end part of the driving cylinder, and the extension part and the main driving shaft are fixedly arranged in the circumferential direction;

the connecting portion is connected with the inner shell and the outer shell.

9. A dose adjustment mechanism as defined in claim 1, further comprising a torsion spring and clutch assembly, comprising:

the torsion spring is sleeved on the outer side of the main driving shaft, one end of the torsion spring is connected with the first shell, and the other end of the torsion spring is connected with the main driving shaft;

The clutch assembly is configured to maintain the torsion spring in a twisted state by the main drive shaft and to release the twisted state of the torsion spring.

10. An injection device, comprising:

The dose regulating mechanism of any one of claims 1 to 9;

the pushing equipment comprises a second shell, a push rod, a locking seat, a rotating seat and a fixing seat, wherein:

The fixed seat is connected with the first shell;

the second shell is connected with the fixed seat and is used for loading a drug carrier;

the push rod is in threaded connection with the fixed seat and is used for acting on the tail part of the drug carrier;

The rotating seat is rotationally arranged on the fixed seat, the main driving shaft is provided with a first driving tooth part, the rotating seat is provided with a second driving tooth part and is used for meshing with the first driving tooth part, and the push rod axially slides with the rotating seat and is circumferentially fixedly arranged;

the locking seat is connected to the fixing seat and used for enabling the rotating seat to be kept on the fixing seat.