TWI646992B - Injection propulsion mechanism with dose control function - Google Patents

Abstract

An injection propulsion mechanism having a dose control function, comprising a dose control component, an operation component, an injection propulsion component and a clutch backstop assembly, wherein the injection propulsion mechanism is applied to the connection pen in the injection pen, except for controlling the injection dose per injection And after repeated use for a certain number of times, the dose control nut and the driving sleeve are relatively engaged back and forth, and after the operating assembly is pressed to advance to complete the injection, the dose control nut is integrated with the driving sleeve, and the driving sleeve passes through the shaft. The tube is unable to rotate due to the blocking action of the clutch backstop assembly, and the dose control solenoid is pinned by the dose control nut, so that the dose control solenoid can no longer be screwed back and locked, and the liquid in the medicament bottle is just used up. In this way, the injection pen must be discarded altogether to ensure the safety of the injection pen.

Description

Injection propulsion mechanism with dose control function

The present invention relates to an injection pen, and more particularly to an injection propulsion mechanism which is applied to the injection pen, provides a dose control function, and can automatically brake and lock after reaching the number of uses, so that the injection pen cannot be reused.

Based on safety regulations for drug injection, currently known injection pen constructions have a limited number of reusable functions. The existing injection pens are divided into two types: a metering type injection pen and a counting type injection pen. Taking a meter type injection pen as an example, the meter type injection pen is attached to the medicine bottle, and is pressed by a push rod action at the rear end of the injection pen. The interlocking control of the internal drive mechanism pushes the piston in the medicament bottle to move a certain stroke distance, and then outputs the pre-dose medicament through the needle.

Although the existing metering type pen can achieve the function of quantitatively outputting the medicine, or further has the effect of saving labor, the driving mechanism in the injection pen can still be operated after the medicine of the injection pen in the medicine bottle is used up, Locked, causing users to continue to misuse, but there is a problem of insufficient security. Today's pens further provide automatic locking to ensure safe use. However, the existing automatic locking function of the injection pen still has shortcomings, which needs to be further improved, in order to provide a more practical injection pen to the user.

The main object of the present invention is to provide an injection propulsion mechanism with a dose control function, which solves the problem that the automatic locking function of the existing injection pen is insufficient.

In order to achieve the foregoing object, the injection propulsion mechanism with dose control function of the present invention comprises a dose control component, an operation component, an injection advancement component and a clutch backstop component, wherein: the dose control component comprises: An outer tube having an axially extending outer tube bore, the bore wall of the outer tube forming a spiral rib; a dose control coil rotatably mounted in the outer tube of the outer tube In the hole, the dose control coil comprises a screwing section having a spiral groove and a rear end portion of the screw at the rear end of the screwing section, the spiral groove of the screwing section and the spiral snail of the outer tube In the dose control coil, an axial through hole of the spiral tube is formed, and the rear ring of the hole in the spiral tube has a plurality of axially extending grooves; a drive sleeve is installed in the dose control In the bore of the solenoid of the solenoid, the drive sleeve includes a front portion of the sleeve and a rear portion of the sleeve located behind the front portion of the sleeve, and a first space opening toward the front is formed in the front portion of the sleeve, the rear portion of the sleeve Forming a second space with an opening facing backward, and the The peripheral wall of the rear section of the tube forms at least one slot that radially communicates with the second space, and a snap-in elastic piece is formed in the slot, and the snap-up elastic piece can be pushed and clamped into the inner phase of the dose control solenoid In the corresponding groove, a front end of the driving sleeve forms a spiral end portion; a screwing tube is installed in the dose control screw, and a rear end of the screwing tube is fixed to the front end of the driving sleeve, Forming an axially through sleeve hole in the threaded tube, the threaded tube comprising a threaded screwing section and a ring flange at the front end of the threaded section; and a dose control nut having a threaded hole therein The dose control nut is disposed in the dose control screw, and is screwed to the screwing section of the screw tube, the dose control nut is located in front of the driving sleeve, and a spiral is formed at the rear end of the dose control nut a limiting portion, the spiral limiting portion can be matched with a screw end of the front end of the driving sleeve to be limited; The operating component is disposed at a rear end of the dose control component, the operating component includes an operating member, a compression spring and a pressing member, the operating member includes a plug portion and a plug end at a rear end of the insert portion The insertion plate portion is inserted into the second space of the driving sleeve, and can push the clamping elastic piece to be engaged in a corresponding groove in the dose control screw, the end of the insertion plate is located An outer side of the rear end of the driving sleeve is inserted into the rear end portion of the screw of the dose control screw, and the compression spring is sleeved on the outer side of the inserting portion of the operating member, and the two ends of the compression spring respectively abut the a rear end of the driving sleeve and the end of the inserting plate, the pressing member is sleeved and disposed outside the end of the inserting plate at the rear end of the operating member; the injection propelling assembly is disposed at the front end of the dose regulating assembly, and the injection propelling assembly comprises a shaft tube, a push rod and a push block, the shaft tube having an axial through hole, the shaft tube comprising a shaft tube body and a front end portion of the shaft tube at the front end of the shaft tube body, the shaft tube The shaft tube body is installed in the screw tube, and the shaft tube can be opposite The screw tube is axially linearly moved. The front end of the shaft tube is located in front of the screw tube and the dose control screw. The push rod is installed in the shaft hole of the shaft tube and can be axially opposite to the shaft tube. a linear motion and rotation together with the shaft tube, the push rod outer peripheral wall is formed with a push rod thread, the push block is disposed at the front end of the push rod; the clutch backstop assembly is disposed inside the front portion of the outer tube, and is located at the The injection control assembly is arranged in front of and in combination with the injection propulsion assembly. The clutch backstop assembly comprises: a front sleeve fixed to the inside of the front end of the outer tube, the rear end of the front sleeve having a set of shell back plates, the sleeve back a sleeve screw hole is formed in the plate, and the push rod screw of the injection propulsion assembly is disposed in the sleeve screw hole, and the rear end surface of the sleeve back plate forms a first ratchet gear portion around the sleeve screw hole, the first a ratchet gear portion has a plurality of annular oblique teeth arranged in a plurality of rings; a rear sleeve is fixed inside the front end of the outer tube and fixed to the rear end of the front sleeve; a clutch member is movably assembled In the rear casing, a middle hole is formed in the clutch member, and is axially movably sleeved on the The shaft tube distal end of the tube, the clutch member can rotate together with the shaft tube, the front end surface of the clutch member having a second ratchet gear portion, said second portion having a plurality of annular ratchet gear arrangement a single oblique ratchet gear, the second ratchet gear portion can be relatively engaged and disengaged from the first ratchet gear portion at the rear end of the front casing; and an ejector spring is disposed in the rear casing and sleeved on the On the front end portion of the shaft tube of the shaft tube, the front and rear ends of the push-up spring respectively abut the clutch member and the shaft tube.

The invention is created by the front injection propulsion mechanism, which mainly utilizes a combination structure of a dose control component, an operation component, an injection propulsion component and a clutch backstop component, so that the injection propulsion mechanism is applied to the injection pen to connect the medicament bottle, and the energy is removed. In addition to controlling the dose of each injection, when the pen is repeatedly used for a certain number of times, it can provide the function of automatic locking and can no longer be used, wherein the dose control nut is driven to spiral backwards a predetermined number of times after the dose control screw The spiral limiting portion of the rear end of the cap is engaged with the screw end of the front end of the driving sleeve, and is combined with the driving sleeve after the pressing member of the operating assembly is pressed forward to complete the injection. In one piece, the drive sleeve is made of a card for the engagement of the front sleeve and the clutch of the clutch backstop assembly through the shaft tube, and the dose control screw is pinned by the dose control nut, so that the dose control screw can no longer be Rotating backwards to produce an automatic locking function. At this time, the liquid in the medicine bottle is also used up, so the user is prompted to Shoot the entire pen must be discarded to ensure safe use of the injection pen.

1‧‧‧Injection propulsion mechanism

10‧‧‧Dose Control Components

11‧‧‧External management

111‧‧‧Outer tube hole

112‧‧‧Spiral ribs

113‧‧‧Fixed ribs

114‧‧‧Perforation

115‧‧‧Limited chute

12‧‧‧Dose control coil

121‧‧‧Spiral hole

122‧‧‧ screw joint

123‧‧‧Spiral rear end

124‧‧‧Spiral groove

126‧‧‧ Limit Oblique Bump

127‧‧‧Flexible buckle

128‧‧‧ trench

129‧‧‧ card tooth ring

12a‧‧‧ ribs

13‧‧‧ drive casing

131‧‧‧The front section of the casing

132‧‧‧The rear section of the casing

133‧‧‧First space

134‧‧‧Second space

135‧‧‧Parts

136‧‧‧ slotting

137‧‧‧Card shrapnel

138‧‧‧Bumps

138a‧‧‧Limited convex

139‧‧‧Spiral end

13a‧‧‧ card hole

13b‧‧‧Snap

14‧‧‧Spiral tube

141‧‧‧ casing hole

142‧‧‧ Guide ribs

143‧‧‧ring flange

144‧‧‧Spinning section

145‧‧‧ Combination Department

146‧‧‧"

147‧‧‧Clamping bumps

148‧‧‧ slot

149‧‧‧ Ring groove

15‧‧‧Dose Control Nuts

151‧‧‧ screw holes

152‧‧‧Spiral Limits

153‧‧‧ slot

20‧‧‧Operating components

21‧‧‧Compression spring

22‧‧‧Operating parts

221‧‧‧Plugboard Department

222‧‧‧ insert end

223‧‧‧Pushing the top bump

224‧‧‧Bump end

23‧‧‧Pressing parts

30‧‧‧Injection propulsion components

31‧‧‧ shaft tube

311‧‧‧Axis hole

312‧‧‧ shaft tube body

313‧‧‧ shaft tube front end

314‧‧‧Ring convex

315‧‧‧ rear guide slot

316‧‧‧ shaft guide ribs

317‧‧‧ front channel

32‧‧‧Put

321‧‧‧Pusher thread

322‧‧‧Pusher guide

33‧‧‧Submission block

40‧‧‧Clutch backstop assembly

41‧‧‧Front casing

411‧‧‧ Included

412‧‧‧Shell back panel

413‧‧‧ Sockets

415‧‧‧shell hole

416‧‧‧First ratchet gear

417‧‧‧ card slot

418‧‧‧ group slot

42‧‧‧ After the casing

421‧‧‧ Sockets

422‧‧‧ Backend board

423‧‧‧ activity slot

424‧‧‧End plate perforation

425‧‧‧ card hook

426‧‧‧ combination slot

43‧‧‧ clutches

431‧‧‧Medium hole

432‧‧‧Second ratchet gear

433‧‧‧ guiding flange

44‧‧‧Pushing spring

50‧‧‧Pharmaceutical bottles

51‧‧‧Piston

60‧‧‧ needle

70‧‧‧needle cover

80‧‧‧ Cover

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective exploded view of a preferred embodiment of an injection propulsion mechanism having a dose control function of the present invention.

2 is a perspective exploded view showing another viewing angle of the preferred embodiment of the injection propulsion mechanism shown in FIG. 1.

3 is a side cross-sectional view showing the preferred embodiment of the injection propulsion mechanism shown in FIGS. 1 and 2.

4 is an enlarged perspective exploded view of the dose control solenoid, the drive sleeve, the screw tube, and the dose control nut in the preferred embodiment of the injection advancement mechanism of FIGS. 1 and 2.

FIG. 5 is an enlarged perspective exploded view showing the shaft tube, the push rod and the clutch backstop assembly in the preferred embodiment of the injection propulsion mechanism shown in FIGS. 1 and 2.

Figure 6 is a partial perspective view showing the clutching and anti-stop assembly of the preferred embodiment of the injection propulsion mechanism of Figure 1 in an engaged state.

Figure 7 is a partial perspective view showing the clutching and stopping assembly of the preferred embodiment of the injection propulsion mechanism of Figure 1 in a disengaged state.

Figure 8 is a side cross-sectional view showing the preferred embodiment of the injection advancement mechanism of Figure 1 applied to an injection pen.

Figure 9 is a side cross-sectional view showing the injection pen and the needle cover of the injection pen shown in Figure 8.

Figure 10 is a side elevational, cross-sectional view of the preferred embodiment of the injection advancement mechanism of the present invention prior to injection.

Figure 11 is a side elevation, partial cross-sectional view of the preferred embodiment of the injection advancement mechanism of the present invention with the operating assembly stretched rearwardly.

Figure 12 is a side elevation, partial cross-sectional view showing the preferred embodiment of the injection advancement mechanism of the present invention with the operating assembly being pressed forward.

Figure 13 is a side elevational cross-sectional view showing the preferred embodiment of the injection propulsion mechanism of the present invention in a locked state after reaching the number of uses.

As shown in FIGS. 1 to 3, a preferred embodiment of the injection propulsion mechanism of the present invention having a dose control function is disclosed. As can be seen from the drawings, the injection propulsion mechanism 1 includes a dose control assembly 10. An operating assembly 20, an injection propulsion assembly 30, and a clutch backstop assembly 40.

As shown in FIGS. 1 through 4, the dose control assembly 10 includes an outer tube 11, a dose control coil 12, a drive sleeve 13, a screw tube 14, and a dose control nut 15.

As shown in FIG. 1 to FIG. 4, an outer tube inner hole 111 is formed in the outer tube 11, and a hole rib 111 is formed in the hole wall of the outer tube hole 111. In the preferred embodiment, The outer tube 11 protrudes from the hole wall of the outer tube hole 111 at least one axially extending fixing rib 113, or further forms a plurality of ring grooves in the hole wall of the outer tube intermediate hole 111. A through hole 114 is formed in the wall of the outer tube 11 and extends through the hole 111 in the outer tube. The outer tube 11 can also form at least one limiting chute 115 in the hole wall of the outer hole 111.

As shown in FIG. 1 to FIG. 4, the dose control screw 12 is rotatably mounted in the outer tube 11, and an axially-through solenoid hole 121 is formed in the dose control screw 12. The screw tube 12 includes a screwing portion 122 and a screw rear end portion 123 at the rear end of the screwing portion 122. The outer peripheral surface of the screwing portion 122 forms a spiral groove 124, and the screwing portion 122 of the dose control screw 12 is screwed. In the outer tube intermediate hole 111 of the outer tube 11, and the spiral rib 112 is screw-fitted with the spiral groove 124, the screw rear end portion 123 is located outside the rear end of the outer tube 11. In the preferred embodiment, the outer peripheral wall of the segment connecting the rear end portion 123 of the screw portion forms at least one limiting oblique protrusion 126, and the limiting oblique protrusion 126 can be limited to the outer tube 11. The bit chute 115 is aligned in place. The front end of the screwing section 122 of the dose control screw 12 can also form a resilient buckle 127. The dose control screw 12 forms a plurality of axially extending ribs 12a on the peripheral wall of the hole in the front section of the hole 121 of the solenoid. The solenoid 12 forms a plurality of axially extending slots 128 in the peripheral wall of the bore of the rear section of the bore 121. A locking ring portion 129 having a plurality of teeth is formed in the rear end portion 123 of the solenoid with respect to the circumferential wall of the hole 121 in the rear of the groove 128.

As shown in FIG. 1 to FIG. 4 , the driving sleeve 13 is mounted in the solenoid hole 121 of the dose control screw 12 , and the driving sleeve 13 includes a sleeve front section 131 and a sleeve rear section 132 . A first space 133 having an opening facing forward is formed in the front portion 131 of the sleeve of the driving sleeve 13, and a second space 134 opening toward the rear is formed in the rear portion 132 of the sleeve, and the first space 133 and the second space 134 are formed. A partitioning portion 135 is formed, and a peripheral wall of the sleeve rear portion 132 forms at least one slot 136 radially communicating with the second space 134. A locking elastic piece 137 is formed in the opening 136, and the elastic piece 137 is formed. The front end is a free end, The snap tabs 137 can be pushed and yawed radially outwardly into the corresponding slots 128 in the dose control solenoid 12. The locking elastic piece 137 has a protrusion 138 at the end of the locking piece 137, and the limiting protrusion 138a is further disposed behind the protrusion 138. The driving sleeve 13 forms a plurality of latches 13b at the rear end of the sleeve rear section 132. The driving sleeve 13 is mounted in the dose control screw 12, and the plurality of latches 13b at the rear end of the driving sleeve 13 are respectively engaged with the locking ring portions 129 of the rear end portion 123 of the screw. The front end of the driving sleeve 13 is formed with a spiral end portion 139. In the preferred embodiment, the side wall of the sleeve front portion 131 is provided with at least one engaging hole 13a, and the second space 134 is a rectangular hole.

As shown in FIG. 1 to FIG. 4, the screwing tube 14 is installed in the dose control screw 12, and the rear end of the screwing tube 14 is connected to the front end of the driving sleeve 13, and is subjected to the dose control screw 12. The front end of the elastic buckle 127 is limited, and an axially through sleeve hole 141 is formed in the screw tube 14 , and an axially extending guiding rib 142 is formed on the hole wall of the sleeve hole 141 . The front end of the joint 14 forms a radially protruding ring flange 143. The outer circumferential surface of the ring flange 143 forms a ring groove 149, and the ring flange 143 defines at least one axially extending groove 148. The ribs 12a in the dose control coil 12 are mated. The screwing tube 14 includes a threaded screwing section 144 having a pitch smaller than a pitch of the helical groove 124 of the dose control coil 12, the screwing tube 14 having a rear end of the screwing section 144 In the preferred embodiment, the combination portion 145 has a plurality of grooves 146 extending axially from the rear end thereof toward the front side, so that the combination portion 145 can be radially contracted and reset, and the outer peripheral surface of the combination portion 145 is formed. There is at least one latching projection 147, and the screwing tube 14 is inserted into the sleeve front section 131 of the driving sleeve 13 by the combining portion 145, and is combined by the concave-convex fitting of the engaging hole 13a corresponding to the engaging projection 147. One.

As shown in FIG. 1 to FIG. 4 , the dose control nut 15 has a screw hole 151 , and the dose control nut 15 is disposed in the dose control screw 12 and is screwed to the screw tube 14 . A screwing section 144, the dose control nut 15 is located in front of the drive sleeve 13. The rear end of the dose control nut 15 forms a spiral limiting portion 152 which can cooperate with the screw end portion 139 of the front end of the driving sleeve 13, and the outer peripheral wall of the dose control nut 15 can also form at least one axis. To the extended slot 153, the slot 153 can The tampon 12a in the dose control coil 12 cooperates with the dose control nut 15 in conjunction with the dose control solenoid 12. In the initial state, the dose control nut 15 is located at the front end position of the screwing section 144 of the screwing tube 14, and the movement control of the dose control nut 15 on the screwing tube 14 is tied to the helical limit portion 152. The screw end 139 at the front end of the drive sleeve 13 at the rear is joined.

As shown in FIG. 1 to FIG. 3, the operating component 20 is disposed at the rear end of the dose control component 10. The operating component 20 includes an operating member 22, a compression spring 21, and a pressing member 23. The operating member 22 includes a a card insertion portion 221 and a card end portion 222 at the rear end of the card insertion portion 221, the front end of the insertion plate portion 221 has an ejector protrusion 223, and the rear end of the ejector protrusion 223 has a bump end portion 224. The operating member 22 is inserted into the second space 134 of the driving sleeve 13. The pushing protrusion 223 is located between the protrusion 138 and the limiting protrusion 138a, and the protruding protrusion 223 is bent by the rear end of the protrusion 223. The end portion 224 is restrained by the limiting convex portion 138a, so that when the operating member 22 is pulled backward, it is not disengaged from the driving sleeve 13, and the insertion plate end portion 222 is located outside the rear end of the driving sleeve 13, and can extend into the dose. The solenoid rear end portion 123 of the solenoid 12 is controlled. The compression spring 21 is sleeved on the outer side of the inserting portion 221 of the operating member 22, and the two ends of the compression spring 21 abut against the rear end of the driving sleeve 13 and the end portion 222 of the inserting plate. The pressing member 23 is sleeved on the operating member 22 On the outer side of the end plate end portion 222 of the rear end, the pressing member 23 and the operating member 22 are relatively rotatable and axially linearly movable, and can enter and exit the rear end portion of the dose control screw 12.

In the foregoing operation assembly 20, the operating member 22 can be pushed forward, and the protruding protrusion 223 is used to push against the protrusion 138 at the end of the locking elastic piece 137 of the driving sleeve 13, so that the locking elastic piece 137 is biased radially outward. The drive sleeve 13 is coupled to the dose control solenoid 12 by being engaged in a corresponding slot 128 in the dose control solenoid 12. The operating member 22 can be pulled rearwardly, and the locking tab 137 is radially inwardly reset to disengage from the corresponding slot 128 in the dose control solenoid 12.

As shown in FIG. 1 to FIG. 3, the injection propulsion assembly 30 is disposed at the front end of the dose control assembly 10. The injection propulsion assembly 30 includes a shaft tube 31, a push rod 32, and a push block 33. The shaft tube 31 has an axial through hole 311, the shaft tube 31 includes a shaft body 312, and a shaft tube a front end portion 313 of the front end of the body 312, and an annular convex portion 314 extending between the shaft body 312 and the front end portion 313 of the shaft tube, and the shaft body 312 of the shaft tube 31 is mounted on the shaft In the screwing tube 14, the shaft tube 31 is linearly movable with respect to the screwing tube 14, and the shaft tube front end portion 313 and the annular convex portion 314 are located in front of the screwing tube 14 and the dose control screw 12. The push rod 32 is mounted in the shaft hole 311 of the shaft tube 31. The push rod 32 can linearly move axially relative to the shaft tube 31, and can rotate together with the shaft tube 31. The outer peripheral wall of the push rod 32 is formed with a push. The rod thread 321 has a pitch smaller than a pitch of the spiral groove 124 of the dose control solenoid 12, and the pitch of the push rod thread 321 is greater than a pitch of a thread of the screwing portion 144 of the screw tube 14. The push block 33 is disposed at the front end of the push rod 32 and is located in front of the shaft tube 31.

As shown in FIG. 1 to FIG. 3 and FIG. 5, in the preferred embodiment, the outer peripheral wall of the push rod 32 further defines at least one push rod guide groove 322 extending axially and passing through the push rod thread 321 . The shaft hole 311 of the hole 311 defines at least one axially extending shaft guide rib 316, and the shaft guide rib 316 extends into the push rod guide 322 to enable the push rod 32 to The shaft tube 31 is axially linearly moved. The outer peripheral wall of the shaft end portion 313 of the shaft tube 31 further defines at least one axially extending leading groove 317. The outer peripheral wall of the shaft body 312 forms at least one axially extending rear guiding groove. 315, the rear guide groove 315 cooperates with the guiding rib 142 in the sleeve hole 141 of the screwing tube 14.

As shown in FIG. 1 to FIG. 3 and FIG. 5 to FIG. 7 , the clutching and stopping assembly 40 is disposed inside the front section of the outer tube 11 and in front of the dose control assembly 10 and assembled with the injection propulsion assembly 30. The clutching and stopping assembly 40 includes a front casing 41, a rear casing 42, a clutch member 43, and an ejector spring 44.

As shown in FIG. 1 to FIG. 3 and FIG. 5 to FIG. 7 , the front casing 41 is disposed outside the front portion of the push rod 32 and fixed to the front end of the outer tube 11 . In the preferred embodiment, the front sleeve The outer peripheral surface of the shell 41 forms at least one axially extending joint groove 418, or a plurality of annular flanges are formed on the outer peripheral surface of the front sleeve, so that the front sleeve 41 is installed in the outer tube inner hole 111 of the outer tube 11, The combination groove 418 is combined with the fixing rib 113, and the ring groove is combined with the ring flange to fix the front casing 41 in the outer tube 11. The front casing 41 includes a set of joint portions 411 and a set of shell back plates 412 at the rear end of the sleeve portion 411, and an opening is formed in the sleeve portion 411 a sleeve hole 413, a sleeve screw hole 415 is formed in the sleeve back plate 412, the sleeve screw hole 415 is connected to the sleeve groove 413, and the push rod 32 of the injection propulsion assembly 30 is screwed to the sleeve screw In the hole 415, the rear end surface of the casing back plate 412 forms a first ratchet gear portion 416 on the periphery of the casing screw hole 415, and the first ratchet gear portion 416 has a plurality of single oblique ratchet teeth arranged in a ring shape.

As shown in FIG. 1 to FIG. 3 and FIG. 5 to FIG. 7 , the rear casing 42 is assembled at the rear end of the front casing 41 and fixed inside the front end of the outer pipe 11 . In the preferred embodiment, the rear casing 42 is combined with the front casing 41 by a snap-fit structure of the hook 425 and the card slot. The rear casing 42 can also form at least one axially extending combination groove 426 on the outer circumferential surface thereof, so that the rear casing 42 It is installed in the outer tube hole 111 of the outer tube 11, and is combined with the fixing rib 113 by the combination groove 426 to fix the rear sleeve 42 in the outer tube 11. The rear casing 42 includes a connecting portion 421 and a rear end plate 422 at the rear end of the socket portion 421. The socket portion 421 defines an opening groove 423 with an opening facing forward, and a connecting hole is formed in the rear end plate 422. The end plate through hole 424 of the movable groove 423, the shaft tube body 312 of the shaft tube 31 is inserted through the end plate through hole 424 of the rear end plate 422, and the shaft tube front end portion 313 of the shaft tube 31 and the annular convex portion 314 are located in the rear sleeve 42. In the movable slot 423, the rear end plate 422 is located between the annular convex portion 314 of the shaft tube 31 and the front end of the dose control solenoid 12.

As shown in FIG. 1 to FIG. 3 and FIG. 5 to FIG. 7 , the clutch member 43 is movably disposed in the movable slot 423 of the rear sleeve 42 , and a middle hole 431 is formed in the clutch member 43 and can be The axial direction of the shaft tube 31 of the shaft tube 31 is axially movably disposed. In the preferred embodiment, the clutch member 43 defines at least one axially extending guiding flange 433 in the hole edge of the hole 431. The guide flange 433 is engaged with the front guide groove 317 of the shaft tube 31 so that the clutch member 43 can move axially forward and backward of the shaft end portion 313 of the shaft tube 31, and the clutch member 43 can rotate together with the shaft tube 31. The shaft tube 31 of the injection propulsion assembly 30 is disposed in the middle hole 431 of the clutch member 43. The front end of the clutch member 43 has a second ratchet gear portion 432, and the second ratchet gear portion 432 has a plurality of annular arrangements. With the single oblique ratchet, the second ratchet gear portion 432 of the clutch member 43 can be relatively engaged and disengaged from the first ratchet gear portion 416 at the rear end of the front casing 41.

As shown in FIG. 1 to FIG. 3 and FIG. 5 to FIG. 7 , the ejector spring 44 is disposed in the movable slot 423 of the rear sleeve 42 and sleeved on the front end portion 313 of the shaft tube 31 . The front and rear ends of the ejector spring 44 respectively abut the clutch member 43 and the annular convex portion 314 of the shaft tube 31. The ejector spring 44 provides an elastic force to the clutch member 43 to make the second ratchet gear of the clutch member 43. The portion 432 is in opposite engagement with the first ratchet gear portion 416 at the rear end of the front casing 41.

Regarding the use case in which the present injection propulsion mechanism 1 is applied to an injection pen, as shown in FIGS. 8 and 9, the rear end of the medicine bottle 50 is assembled to the fitting portion 411 of the front casing 41 of the clutch backstop assembly 40. The pushing block 33 disposed at the front end of the push rod 32 can extend into the bottle body of the medicine bottle 50 to abut the piston 51. The front end of the medicine bottle 50 is provided with a needle 60, and a needle cover 70 can be disposed outside the needle 60, or Further, a cover type cover 80 is sleeved on the outer side of the needle cover 70 and the medicine bottle 50, and the rear end of the cover 80 is sleeved outside the sleeve portion 411 of the front cover 41 to provide a safety protection function.

As shown in Figs. 9 and 10, at the time of injection, the cover 80 and the needle cover 70 are removed, and the needle 60 is inserted into a predetermined injection site of the human body to perform quantitative injection of the drug. During the operation of the quantitative injection of the medicament, as shown in FIG. 11 to FIG. 12, the pressing member 23 of the pulling operation assembly 20 is moved backward to a certain distance beyond the rear end of the outer tube 11, and then the clutch is stopped. The front casing 41 and the rear casing 42 of the 40 are fixed in the outer tube 11, and the first ratchet gear portion 416 at the rear end of the front casing 41 and the second ratchet gear portion 432 at the front end of the clutch member 43 are engaged with each other. The shaft tube 31 is prevented from rotating, and the driving sleeve 13 and the screwing tube 14 are restricted from being interlocked with the operating member 22 by the shaft tube 31, and the screwing tube 14 can only be translated backward. The dose control screw 12 During the backward movement with the driving sleeve 13 and the screwing tube 14, the dose control screw 12 is reversely spiraled rearward relative to the outer tube 11 by the screwing configuration between the outer tube 11 and the dose control screw 12. The predetermined number of turns, the rotation of the dose control screw 12, also drives the dose control nut 15 to move a certain stroke on the screwing tube 14 by a predetermined number of turns from the front to the back, and the plurality of spring buckles at the rear end of the driving sleeve 13 are driven. 13b bounces at the carding ring portion 129 of the rear end portion 123 of the solenoid to make a sound.

As shown in FIG. 11 to FIG. 12, when the user presses the pressing member 23 of the operation unit 20 forward, the insertion portion 221 of the operating member 22 is advanced forward, and the locking elastic piece 137 of the driving sleeve 13 is pushed. The locking elastic piece 137 is biased radially outwardly into the corresponding groove 128 in the dose control screw 12, so that the driving sleeve 13 is coupled with the dose control screw 12, and is connected by the outer tube 11 a screwing structure with the dose control screw 12, and the drive sleeve 13, the dose control screw 12, the screwing tube 14, and the dose control nut 15 screwed on the screw tube 14 together with the outside of the shaft tube 31 On the other hand, the shaft tube 31 is rotated at a fixed point via the screwing tube 14, wherein the first ratchet gear portion 416 at the rear end of the front casing 41 and the second ratchet gear portion 432 at the front end of the clutch member 43 are monoclinic. When the shaft tube 31 is rotated, the clutch member 43 is also rotated with the coaxial tube 31, and the push-up member 44 is pushed and compressed by the inclined surface between the single oblique ratchets to make the clutch member 43. The second ratchet gear portion 432 can be temporarily disengaged from the first ratchet gear portion 416 at the rear end of the front casing 41, so that the clutch member 43 and the shaft When the 31 rotates together, the push rod 32 is rotated by the fixed point rotating shaft tube 31 to generate a rotary motion, and the rotating push rod 32 is advanced by the screwing structure between the push rod 32 and the front sleeve 41, and the front end of the push rod 32 is further advanced. The push block 33 applies a forward thrust to the piston 51 in the drug bottle 50, and a certain amount of the drug solution in the drug bottle 50 is injected into the body through the needle 60.

The injection pen can be reused a limited number of times. In order to ensure the safety of the injection, after each injection, the needle 60 must be discarded, the new needle 60 is re-replaced and the injection is performed, and the operation assembly 20 is pulled back each time. During the process, the dose control nut 15 is spirally moved by a certain stroke of the front end of the driving sleeve 13 on the screwing tube 14 according to the preset number of times of use of the injection pen, the dose of the injection liquid, and the inside of the medicine bottle 50. Determined by the dose of liquid medicine. As shown in FIG. 13, after the dose control nut 15 is driven to spiral back a predetermined number of times, the spiral stop portion 152 at the rear end of the dose control nut 15 is engaged with the screw end portion 139 of the front end of the drive sleeve 13 In combination, and after the pressing member 23 of the operating assembly 20 is pressed forward to the completion of the injection, since the dose control nut 15 is integrated with the driving sleeve 13, the driving sleeve 13 is passed through the shaft tube 31 as the front of the clutching and stopping assembly 40. The card in which the sleeve 41 and the clutch member 43 are engaged with each other cannot be rotated, and the dose control screw 12 is pinned by the dose control nut 15, resulting in a dose tube The screw 12 can no longer be screwed back. At this time, the liquid medicine in the medicine bottle 50 is also used up, and the injection pen must be completely discarded.

According to the above description, the present invention mainly utilizes a combination configuration of a dose control component, an operation component, an injection propulsion component and a clutch backstop component, so that the injection propulsion mechanism can control each injection after applying the medicine bottle in the injection pen. In addition to the dose, when the pen is repeatedly used for a certain number of times, it can provide the function of automatic locking and can no longer be used, wherein the screw limit of the rear end of the dose control nut is driven after the dose control nut is driven back spiraling a predetermined number of times. The position portion is engaged with the screw end portion of the front end of the driving sleeve, and is coupled to the front end of the driving sleeve, and after the pressing member of the operating assembly is pressed forward to complete the injection, the dose control nut is integrated with the driving sleeve to drive the sleeve. The needle tube is made of a card for engaging the clutch sleeve and the clutch member of the clutch backstop assembly, and the dose control screw is pinned by the dose control nut, so that the dose control screw can no longer be rotated backwards. In this way, the user is prompted to the entire pen to be discarded, ensuring the safety of the pen.

Claims (10)

An injection propulsion mechanism having a dose control function includes a dose control assembly, an operation assembly, an injection advancement assembly, and a clutch backstop assembly, wherein: the dose control assembly comprises: an outer tube having an axial direction a through hole of the outer tube, the hole wall of the hole in the outer tube forms a spiral ridge; a dose control screw is rotatably mounted in the middle hole of the outer tube of the outer tube, the dose control coil comprises a screwing section having a spiral groove and a rear end portion of the screw at a rear end of the screwing section, the spiral groove of the screwing section is screwed with the spiral rib of the outer tube, and the dose control coil is formed An axially through hole of the spiral tube, wherein the rear annular wall of the spiral tube has a plurality of axially extending grooves; a driving sleeve is installed in the hole of the screw of the dose control screw; The driving sleeve includes a front portion of the sleeve and a rear portion of the sleeve behind the front portion of the sleeve. The front portion of the sleeve forms a first space opening toward the front, and the second portion of the sleeve is formed with a second opening toward the rear. Space, and the peripheral wall of the rear section of the casing forms at least one diameter a slot that communicates with the second space, and a snap tab formed in the slot, the clip shrapnel can be pushed and clamped into a corresponding slot in the dose control solenoid, the drive The front end of the sleeve forms a spiral end portion; a screwing tube is installed in the dose control screw, the rear end of the screwing tube is fixed to the front end of the driving sleeve, and an axial direction is formed in the screwing tube a through sleeve hole, the screw tube includes a threaded screwing section and a ring flange at a front end of the screwing section; and a dose control nut having a screw hole therein, the dose control nut mounting In the dose control screw, and screwed in the screwing section of the screw tube, the dose control nut is located in front of the driving sleeve, and a spiral limiting portion is formed at the rear end of the dose control nut, the spiral limit The portion can be matched with the screw end of the front end of the driving sleeve to be limited; The operating component is disposed at a rear end of the dose control component, the operating component includes an operating member, a compression spring and a pressing member, the operating member includes a plug portion and a plug end at a rear end of the insert portion The insertion plate portion is inserted into the second space of the driving sleeve, and can push the clamping elastic piece to be engaged in a corresponding groove in the dose control screw, the end of the insertion plate is located An outer side of the rear end of the driving sleeve is inserted into the rear end portion of the screw of the dose control screw, and the compression spring is sleeved on the outer side of the inserting portion of the operating member, and the two ends of the compression spring respectively abut the a rear end of the driving sleeve and the end of the inserting plate, the pressing member is sleeved and disposed outside the end of the inserting plate at the rear end of the operating member; the injection propelling assembly is disposed at the front end of the dose regulating assembly, and the injection propelling assembly comprises a shaft tube, a push rod and a push block, the shaft tube having an axial through hole, the shaft tube comprising a shaft tube body and a front end portion of the shaft tube at the front end of the shaft tube body, the shaft tube The shaft tube body is installed in the screw tube, and the shaft tube can be opposite The screw tube is axially linearly moved. The front end of the shaft tube is located in front of the screw tube and the dose control screw. The push rod is installed in the shaft hole of the shaft tube and can be axially opposite to the shaft tube. a linear motion and rotation together with the shaft tube, the push rod outer peripheral wall is formed with a push rod thread, the push block is disposed at the front end of the push rod; the clutch backstop assembly is disposed inside the front portion of the outer tube, and is located at the The injection control assembly is arranged in front of and in combination with the injection propulsion assembly. The clutch backstop assembly comprises: a front sleeve fixed to the inside of the front end of the outer tube, the rear end of the front sleeve having a set of shell back plates, the sleeve back a sleeve screw hole is formed in the plate, and the push rod screw of the injection propulsion assembly is disposed in the sleeve screw hole, and the rear end surface of the sleeve back plate forms a first ratchet gear portion around the sleeve screw hole, the first a ratchet gear portion has a plurality of annular oblique teeth arranged in a plurality of rings; a rear sleeve is fixed inside the front end of the outer tube and fixed to the rear end of the front sleeve; a clutch member is movably assembled In the rear casing, a middle hole is formed in the clutch member, and is axially movably sleeved on the The shaft tube distal end of the tube, the clutch member can rotate together with the shaft tube, the front end surface of the clutch member having a second ratchet gear portion, said second portion having a plurality of annular ratchet gear arrangement a single oblique ratchet gear, the second ratchet gear portion can be relatively engaged and disengaged from the first ratchet gear portion at the rear end of the front casing; and an ejector spring is disposed in the rear casing and sleeved on the On the front end portion of the shaft tube of the shaft tube, the front and rear ends of the push-up spring respectively abut the clutch member and the shaft tube. An injection propulsion mechanism having a dose control function according to claim 1, wherein the dose control solenoid forms a card having a plurality of card teeth in a rear portion of the rear end portion of the solenoid with respect to a circumferential wall behind the groove. The toothed ring portion has a plurality of latches formed at the rear end of the sleeve rear section, and the plurality of snap fasteners are respectively engaged with the snap ring portions of the rear end portion of the screw. The injection propulsion mechanism with a dose control function according to claim 2, wherein the outer tube forms at least one limit chute in the hole wall of the inner hole of the outer tube; the screwing section of the dose control screw is connected The outer peripheral wall of the segment of the rear end portion of the spiral tube forms at least one limiting oblique protrusion, and the limiting oblique convex block can be aligned with the limiting oblique groove of the outer tube. The injection propulsion mechanism of claim 2, wherein the front end of the screwing section of the dose control screw forms a resilient buckle, and the screwing tube is restrained by the elastic buckle. The injection propulsion mechanism of claim 4, wherein the side wall of the sleeve of the driving sleeve is provided with at least one engaging hole, and the screwing tube has a combination at the rear end of the screwing section. The assembly portion has a plurality of grooving grooves extending axially from the rear end thereof toward the front side, and the outer peripheral surface of the combining portion is formed with at least one latching projection, and the combined portion is placed in the front portion of the sleeve of the driving sleeve. And the card engaging protrusions are combined with the corresponding engaging holes for engaging and fitting. The injection propulsion mechanism having a dose control function according to any one of claims 1 to 5, wherein the locking elastic piece end of the driving sleeve has a convex piece, and the clamping elastic piece is disposed behind the convex piece a limiting protrusion, the front end of the inserting portion of the operating member has a pushing protrusion, and the pushing the top of the protruding block The end has a bump end, and the push top bump is located between the bump and the limiting protrusion, and the end of the bump at the rear end of the push block can be limited by the limiting protrusion. The injection propulsion mechanism having a dose control function according to any one of claims 1 to 5, wherein a pitch of the screwing section of the screwing tube is smaller than a pitch of the spiral groove of the dose control solenoid, the pusher thread The pitch of the screw is smaller than the pitch of the spiral groove of the dose control solenoid, and the pitch of the pusher thread is greater than the pitch of the thread of the screwing portion of the screw. The injection propulsion mechanism with a dose control function according to claim 6, wherein a pitch of the screwing section of the screwing tube is smaller than a pitch of the spiral groove of the dose control screw, and a pitch of the push rod thread is smaller than the dose control The pitch of the spiral groove of the solenoid, and the pitch of the pusher thread is greater than the pitch of the thread of the screwing section of the screw. The injection propulsion mechanism with a dose control function according to claim 8, wherein the outer peripheral wall of the push rod forms at least one push rod guide groove extending axially and passing through the push rod thread, and the shaft hole wall of the shaft tube is formed At least one axially extending shaft tube guiding rib, the shaft tube guiding rib correspondingly extending into the push rod guiding groove; the outer peripheral wall of the front end portion of the shaft tube of the shaft tube forming at least one axially extending leading end a groove, the outer peripheral wall of the shaft tube is formed with at least one axially extending rear guide groove, and at least one axially extending guide rib is formed in the sleeve hole of the screw tube, the rear guide groove and the screw tube a guiding rib in the sleeve hole; the dose control coil forms a plurality of axially extending ribs on the peripheral wall of the hole in the front section of the spiral tube, and the ring flange at the front end of the screw tube forms at least one axial extension a slot that mates with a ridge in the dose control solenoid. The injection propulsion mechanism with a dose control function according to claim 9, wherein the shaft tube has an annular convex portion between the shaft tube body and the front end portion of the shaft tube, and the annular convex portion is located at the screw tube a front side of the dose control coil; the rear sleeve includes a sleeve portion having a movable slot and a rear end plate at a rear end of the sleeve portion, the end plate forming a through hole perforation communicating with the movable slot The shaft tube body of the shaft tube is disposed in the end plate perforation, the front end portion of the shaft tube and the annular convex portion are located in the movable groove of the rear sleeve, and the rear end plate is located at the annular convex portion of the shaft tube Rear of the department with the dose control screw Between the front ends of the tubes, the clutch member and the ejector spring are located in the movable slot, and the rear end of the ejector spring abuts against the annular protrusion of the shaft tube.