CN111714725A

CN111714725A - Injection pen capable of achieving multiple quantitative injections

Info

Publication number: CN111714725A
Application number: CN202010677208.2A
Authority: CN
Inventors: 侯士双; 胡高扬; 陈常娇
Original assignee: Ningbo Ruiai Product Design Co ltd
Current assignee: Ningbo Ruiai Product Design Co ltd
Priority date: 2020-07-14
Filing date: 2020-07-14
Publication date: 2020-09-29
Anticipated expiration: 2040-07-14
Also published as: CN111714725B

Abstract

The application discloses an injection pen capable of realizing multiple quantitative injections, which comprises a shell, a medicine tube assembly, a protective sleeve and a quantitative adjusting mechanism; the quantitative adjusting mechanism comprises a rear support rotatably mounted on the shell, a threaded rod in threaded fit with the shell, and a locking sleeve sleeved on the outer side of the threaded rod and locked with the threaded rod in the circumferential direction; the protective sleeve is axially slidably mounted on the shell and abutted against the locking sleeve, and the locking sleeve is driven by the protective sleeve to be provided with a locking position circumferentially locked with the shell and an injection position circumferentially unlocked with the shell; the after-poppet with through the cooperation of interior ratchet structure between the locking cover, this application has the effect that reduces the probability of the extravagant phenomenon of liquid medicine when the injection needle tubing of the injection pen of many times ration injection does not insert the patient internal.

Description

Injection pen capable of achieving multiple quantitative injections

Technical Field

The application relates to the field of injectors, in particular to an injection pen for multiple quantitative injections.

Background

Existing injection pens are mainly divided into two types: one is an automatic injection pen, which needs to inject all the liquid medicine in a medicine tube into the body of a user in one injection, i.e. the automatic injection pen can be used only once; the other type is an injection pen with multiple times of quantitative injection, when a user uses the injection pen with multiple times of quantitative injection, the liquid medicine in the traditional Chinese medicine tube of the injection pen with multiple times of quantitative injection can be divided into several times of injection into the body, and the injection pen with multiple times of quantitative injection can be used for multiple times, so that the requirements of patients are met.

The existing injection pen for multiple times of quantitative injection is provided with the quantitative injection mechanism, a patient can adjust the injection pen for multiple times of quantitative injection from a locking state to an injection state by adjusting the quantitative injection mechanism, and the liquid medicine in the injection pen for multiple times of quantitative injection can be output by pressing the tail cap of the injection pen for multiple times of quantitative injection.

With regard to the above-mentioned related art, the inventor of the present application has found that the above-mentioned injection pen with multiple quantitative injections has a defect that when a patient does not insert the injection needle tube of the injection pen with multiple quantitative injections into the body, the medical fluid in the injection pen with multiple quantitative injections can be output by pressing the tail cap, which easily causes waste of the medical fluid.

Disclosure of Invention

In order to reduce the probability of the phenomenon of liquid medicine waste when the injection needle tube of the injection pen for multiple times of quantitative injection is not inserted into the body of a patient, the application provides an injection pen for multiple times of quantitative injection.

The application provides an injection pen of many times ration injection adopts following technical scheme:

an injection pen for multiple quantitative injection comprises a shell, a medicine tube assembly, a protective sleeve and a quantitative adjusting mechanism; the quantitative adjusting mechanism comprises a rear support rotatably mounted on the shell, a threaded rod in threaded fit with the shell, and a locking sleeve sleeved on the outer side of the threaded rod and locked with the threaded rod in the circumferential direction; the protective sleeve is axially slidably mounted on the shell and abutted against the locking sleeve, and the locking sleeve is driven by the protective sleeve to be provided with a locking position circumferentially locked with the shell and an injection position circumferentially unlocked with the shell; the rear support is rotatably mounted on the shell and is provided with an initial station and a preparation station which are arranged circumferentially; the rear bracket and the locking sleeve are matched through an inner ratchet wheel structure, the rear bracket rotates from the initial station to the preparation station, and the rear bracket does not drive the locking seat to rotate; when the rear support rotates from the preparation station to the initial station, the rear support drives the locking seat to synchronously rotate and drives the threaded rod to feed.

By adopting the technical scheme, the injection pen for multiple times of quantitative injection is unlocked from the circumferential direction of the shell only after the locking sleeve axially slides to the injection position from the locking position, so that the injection pen for multiple times of quantitative injection is used as follows: 1. medicine feeding operation: circumferentially moving the rear support from the initial station to a preparation station; 2. the front end of the protective sleeve is abutted against the body of a patient, and an injection pen for multiple times of quantitative injection is pressed down, so that the protective sleeve drives the locking sleeve to move from the locking station to the injection station; 3. and (3) injection operation: reset the after-poppet to initial station from preparing station circumference, at this in-process, the after-poppet is rotatory through interior ratchet structure drive protective sheath, because threaded rod circumference locks in the locking cover for the threaded rod synchronous revolution, and threaded rod and casing screw-thread fit, thereby realize that the threaded rod takes place to feed, exports the liquid medicine in the pencil subassembly.

The injection pen enables the front end of the protective sleeve to be abutted against the body surface of a patient, and the operation of pressing down the injection pen for multiple times of quantitative injection becomes the necessary operation of injecting liquid medicine by the injection pen for multiple times of quantitative injection, and is beneficial to reducing the probability of liquid medicine waste when the injection needle tube of the medicine tube assembly is not inserted into the body of the patient. Meanwhile, the injection pen is provided with the protective sleeve structure, so that the injection needle tube can be perpendicularly penetrated into the body of a patient, and the safety performance of the injection pen is improved.

Preferably, the inner ratchet structure comprises an elastic ratchet which is axially slidably mounted on the rear support, a ratchet groove which is formed in the locking sleeve and used for placing the elastic ratchet, and ratchets which are arranged on the inner wall of the ratchet groove; the elastic ratchet wheel is locked with the rear support in the circumferential direction; the elastic ratchet wheel is provided with an elastic pawl which always tends to be abutted against the inner wall of the ratchet wheel groove; when the rear support is at the preparation station, the elastic pawl abuts against the locking end face of the ratchet.

By adopting the technical scheme, when the rear support circumferentially rotates to the preparation station from the initial station, the elastic pawl of the elastic ratchet wheel slides from the locking end surface of the previous ratchet wheel to the locking end surface of the next ratchet wheel, in the process, the rear support cannot drive the locking seat to rotate, and in the process, when the elastic pawl slides from the next ratchet wheel, the elastic pawl can impact on the inner groove wall of the ratchet wheel groove to give a medicine feeding completion prompt sound that the rear support reaches the preparation station; when the rear support is reset to the initial station from the preparation station, the elastic pawl abuts against the locking end face of the next ratchet, so that the rear support drives the locking sleeve to synchronously rotate, and the next ratchet rotates to the position of the previous ratchet.

Preferably, a plurality of side sound projection portions are arranged on the inner wall of the ratchet groove at intervals in the circumferential direction between the adjacent ratchet teeth.

Through adopting above-mentioned technical scheme, when the after bracing by initial station circumferential direction to prepare the in-process of station, the elasticity ratchet of elasticity ratchet can slide from side sound production convex part, produces the suggestion sound of "chuck", the suggestion patient after bracing is just sliding to prepare the in-process of station from initial station. Meanwhile, the convex part is arranged on the side, so that the damping force applied to the elastic ratchet wheel when the elastic ratchet wheel rotates relative to the locking sleeve in the ratchet groove is increased, the rotating speed of the elastic ratchet wheel in the ratchet groove is reduced, and the body feeling of a patient when medicine is administered is improved.

Preferably, the outer wall of the rear bracket is provided with a locking convex tooth, and the front end of the locking convex tooth is provided with a first locking surface; a locking seat which is positioned outside the rear support and is abutted against the rear end of the locking sleeve is axially and slidably arranged in the shell; the locking seat is provided with a locking hook, and the rear end of the locking hook is provided with a second locking surface; when the rear bracket is positioned at the initial station, the first locking surface and the second locking surface are opposite, and when the protective sleeve moves upwards until the first locking surface and the second locking surface are abutted, the injection needle tube is positioned in the protective sleeve; when the rear bracket is in the preparation station, the first locking surface and the second locking surface are circumferentially staggered.

Through adopting above-mentioned technical scheme, the cooperation of locking dogtooth and locking trip among the injection pen of above-mentioned many times ration injection for when the after-poppet did not remove to the preparation station from initial station, the first locking surface of locking dogtooth and the second locking surface of locking trip are just right, make the patient when pressing the protective sheath, the injection needle pipe can not show out from the protective sheath, make the after-poppet remove to the operation of preparing the station from initial station, it is also the necessary operation that the operation of adding medicine becomes the injection needle pipe and shows out from the protective sheath, the security performance of the injection pen of above-mentioned many times ration injection has been improved.

Preferably, the quantitative adjusting mechanism further comprises a return spring, the front end of the return spring abuts against the locking seat, and the rear end of the return spring abuts against the shell.

Through adopting above-mentioned technical scheme, reset spring makes the locking seat have the trend of low pressure on the locking cover all the time, also makes the locking cover have the trend that is in the lock position all the time, when the injection pen that the patient will be quantitative injection many times takes off from the body surface, and reset spring drive locking cover, locking seat and protective sheath reset.

Preferably, a plurality of first sound-emitting convex parts are circumferentially arranged on the rear end surface of the locking sleeve at intervals; and a plurality of second sounding convex parts are circumferentially arranged on the front end surface of the locking seat at intervals.

Through adopting above-mentioned technical scheme, the cooperation of first sound-producing convex part and second sound-producing convex part for can produce the sound that "chuck" when locking cover and locking seat rotate relatively, the suggestion patient locking cover is still in the in-process from preparing station rotation reset to initial station, and the injection pen of suggestion ration injection many times is still injecting the liquid medicine. Simultaneously, the cooperation of first sound-producing convex part and second sound-producing convex part has improved the cooperation intensity of locking cover and locking seat for the rotation of locking cover is more stable at the injection in-process.

Preferably, the rear bracket has a driving part, and an outer side wall of the driving part has a driving thread groove; a tail cover is axially and slidably mounted at the tail end of the shell, and is provided with a driving convex part inserted into the driving thread groove; the tail cover is provided with a covering station and a pulling station; when the tail cover is positioned at the covering station, the rear support is positioned at an initial station; when the tail cover is at the extraction station, the rear support is at the preparation station.

By adopting the technical scheme, the rear support and the tail cover are matched with the driving thread groove and the driving convex part, so that the circumferential position of the rear support is adjusted by pulling and pressing the tail cover, and the tail cover is pulled from the cover closing station to the pulling-out station in the medicine feeding process of the injection pen for carrying out multi-time quantitative injection, so that the rear support circumferentially rotates to the preparation station from the initial station; and then the cup cover is pressed to the covering station from the pulling station, so that the rear bracket rotates to the initial station from the preparation station, the threaded rod forwards feeds a unit length in the process, and the liquid medicine in the medicine tube assembly outputs a unit dosage.

Above-mentioned injection pen of many times ration injection can realize the operation of adding medicine and injection operation through pulling out the tail-hood and pushing down the tail-hood, and this kind of operation is comparatively simple and convenient, and can also be after once adding medicine operation and injection operation, pulls out the tail-hood once more and pushes down the tail-hood, under the condition that does not pull out patient's health with the injection needle tubing of the injection pen of many times ration injection, has realized the injection pen's of many times ration injection once more injection.

Preferably, the protective sleeve comprises a fixing protective sleeve and an actuating protective sleeve; fixed protective sheath has axial spout and circumference spout, the circumference spout connect in the front end of axial spout, it has can to start the protective sheath the circumference spout with the protruding part that slides in the axial spout.

Through adopting above-mentioned technical scheme, the structure of above-mentioned protective sheath is set for, has reduced the storage volume of protective sheath, also can conveniently install injection needle tubing on the pencil subassembly simultaneously. Wherein, the protective sheath comprises fixed protective sheath and start-up protective sheath, helps the length through adjusting fixed protective sheath and start-up protective sheath to make above-mentioned injection pen when setting the injection needle tubing of different length, the homoenergetic makes the length of pricking the internal injection needle tubing of patient at suitable within range, has improved above-mentioned injection pen to the adaptation degree of injection needle tubing.

Preferably, the locking sleeve includes a ratchet portion and a locking portion, the locking portion is circumferentially provided with a locking insertion groove with an open front end, and the housing has a locking insertion post inserted into the locking insertion groove; when the locking sleeve is in the locked position, the locking insert post is inserted into the locking slot; when the locking sleeve is in the injection position, the locking plug is disengaged from the locking socket.

Through adopting above-mentioned technical scheme, the locking sleeve has realized through the cooperation of locking slot and locking inserted column between locking sleeve and the casing that the locking sleeve is when the lock position and the circumferential locking between the casing.

Preferably, the threaded rod is provided with a screw section and a screw guide groove is axially formed in the screw section; the locking sleeve is provided with a guide tangent plane matched with the tangent plane of the screw rod, and a guide block matched with the screw rod guide groove is arranged on the guide tangent plane.

Through adopting above-mentioned technical scheme, through screw rod tangent plane and the cooperation of direction tangent plane between threaded rod and the locking cover realized the circumference locking between threaded rod and the locking cover, and further promoted the circumference locking effect between threaded rod and the locking cover through the cooperation that sets up screw rod guide slot and guide block.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the injection pen with multiple times of quantitative injections enables the front end of the protective sleeve to be abutted against the body surface of a patient, and the operation of pressing down the injection pen with multiple times of quantitative injections becomes the necessary operation of injecting liquid medicine by the injection pen with multiple times of quantitative injections, so that the probability of liquid medicine waste when an injection needle tube of a medicine tube assembly is not inserted into the body of the patient is favorably reduced, and the setting of the protective sleeve is favorable for vertically pricking the injection needle of the injection pen into the body of the patient;

2. the inner ratchet structure comprises an elastic ratchet wheel arranged on the rear support, a ratchet groove formed in the locking sleeve and ratchets arranged on the inner wall of the ratchet groove, the elastic ratchet wheel is provided with an elastic pawl which always tends to be abutted against the inner wall of the ratchet groove, so that when the rear support circumferentially rotates to a preparation station from an initial station and the elastic pawl slides down from the next ratchet, the elastic pawl can impact on the inner groove wall of the ratchet groove to give a medicine feeding completion prompt sound when the rear support reaches the preparation station;

3. the locking convex teeth are arranged on the rear bracket, and the locking clamping hook is arranged on the locking seat, so that the rear bracket is moved from the initial station to the preparation station, the medicine feeding operation is changed into the necessary operation that the injection needle tube of the medicine tube assembly is exposed from the protective sleeve, and the safety performance of the injection pen for multiple quantitative injections is improved;

4. the rear support is provided with a driving part, the outer wall of the driving part is provided with a driving thread groove, the tail end of the shell is provided with a tail cover, and the tail cover is provided with a driving convex part matched with the driving thread groove, so that the medicine feeding operation and the injection operation of the injection pen for multiple times of quantitative injection are simple and convenient, and the continuous injection of the injection pen for multiple times of quantitative injection is facilitated.

Drawings

Fig. 1 is a schematic structural diagram of an injection pen for multiple quantitative injections.

Fig. 2 is an exploded view of a multi-shot injection pen without a needle assembly mounted thereto.

Fig. 3 is a schematic structural diagram of the connecting seat.

Fig. 4 is a schematic structural view of the front case.

Fig. 5 is a structural schematic view of the rear case.

Fig. 6 is a schematic structural view of the cartridge assembly.

Figure 7 is a schematic cross-sectional view of the cartridge assembly.

Figure 8 is an exploded view of the protective sheath.

Fig. 9 is a bottom view of the connection holder.

Figure 10 is a schematic view of the activation sleeve.

Fig. 11 is a schematic structural view of a multi-shot injection pen in a mounted state on a protective cover.

Fig. 12 is a schematic structural view of a multi-dose injection pen with a protective cap in an injection state.

Fig. 13 is a schematic cross-sectional view of the rear housing.

Fig. 14 is a schematic structural view of the rear bracket.

Fig. 15 is a schematic structural view of the tail cap.

FIG. 16 is a schematic view of a multi-shot injection pen with the locking sleeve in the locked position and the tail cap in the capping station.

FIG. 17 is a schematic view of an injection pen with multiple metered injections with the locking sleeve in the injection position and the tail cap in the withdrawal position.

Fig. 18 is an enlarged view at a in fig. 16.

Fig. 19 is an enlarged view at B in fig. 17.

Fig. 20 is an exploded view of the rear housing, the boot cover, and the tail.

Fig. 21 is a schematic view of a threaded rod.

Fig. 22 is a cross-sectional view of the connecting socket.

FIG. 23 is a schematic view of the construction of the locking sleeve.

Figure 24 is a top view of the locking sleeve.

FIG. 25 is a schematic view of the engagement of the rear bracket and the resilient ratchet.

Fig. 26 is a top view of the lock base.

Fig. 27 is a bottom structure view of the lock base.

In the figure: 11. a front housing; 111. a first accommodating cavity; 112. a second section; 113. a first clip strip; 12. a rear housing; 121. a second accommodating cavity; 122. a first bayonet; 123. installing a convex ring; 1231. a supporting convex ring; 124. a locking cylinder; 1241. a third guide groove; 125. a third buckle; 126. a tail end slide block; 127. a fourth section; 13. a connecting seat; 131. a front mounting portion; 1311. a first section; 1312. a first card slot; 1313. a second bayonet; 132. a rear mounting portion; 1321. a third section; 1322. a first buckle; 133. installing a limiting sheet; 134. triggering the through groove; 135. a locking sleeve; 1351. locking the bottom plate; 1352. a threaded through hole; 1353. locking the insert column; 136. a lower limit seat; 21. a needle cannula sleeve; 211. installing a cavity; 212. a first mounting port; 213. a first injection port; 214. a first support section; 215. a second buckle; 216. a needle tube mounting head; 217. a first guide bar; 218. a second guide bar; 219. a fourth guide bar; 22. a cartridge bottle; 23. a needle tube mounting base; 24. injecting a needle tube; 25. a first shield; 26. a second shield; 3. a protective sleeve; 31. fixing a protective sleeve; 311. triggering the inserting sheet; 312. a limiting convex part; 313. a first guide groove; 315. a second guide groove; 316. a circumferential chute; 317. an axial chute; 318. elastic buckle; 319. sliding and opening; 3191. a limiting elastic sheet; 32. starting the protective sleeve; 321. a slip projection; 322. limiting and flanging; 4. a rear bracket; 41. a stent sleeve; 411. a bracket guide groove; 42. mounting a disc; 43. a drive section; 431. a drive thread groove; 44. an elastic ratchet wheel; 441. a ratchet wheel guide bar; 442. an elastic pawl; 45. locking the convex teeth; 451. a first locking surface; 5. a threaded rod; 51. cutting the screw into a section; 52. a screw guide groove; 53. a threaded rod sleeve; 6. a locking sleeve; 61. a locking portion; 611. locking the slot; 62. a ratchet portion; 621. a ratchet groove; 622. a ratchet; 6221. a locking end face; 623. a side sounding protrusion; 63. a step surface; 64. a drive through hole; 65. guiding the section; 66. a guide block; 67. a first sound-emitting protrusion; 7. a locking seat; 71. a fourth guide groove; 72. a second sounding convex portion; 73. locking the clamping hook; 731. a second locking surface; 8. a tail cover; 81. a pen tail sleeve; 811. a fifth section; 812. a tail end chute; 813. a fourth clamping part; 814. a guide surface; 82. a pen tail; 821. a drive sleeve; 8211. a third guide bar; 822. a drive boss; 823. a pen tail cover plate; 824. a fourth buckle; 9. a return spring.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The embodiment of the application discloses an injection pen capable of achieving multiple times of quantitative injection. Referring to fig. 1 and 2, the injection pen for multiple metered injections comprises a housing, a cartridge assembly, a protective sheath 3 and a metering adjustment mechanism. The injection pen for multiple quantitative injections is also provided with a needle assembly.

In this embodiment, the injection end of the injection pen for multiple quantitative injections is defined as the front end thereof, and the tail end of the injection pen for multiple quantitative injections is defined as the rear end thereof.

The housing includes a front housing 11, a rear housing 12, and a connection socket 13.

Referring to fig. 2 and 3, the connecting socket 13 is connected between the front case 11 and the rear case 12, and the connecting socket 13 has a front mounting portion 131 to be fitted with the front case 11, a rear mounting portion 132 to be fitted with the rear case 12, and a mounting stopper 133 between the front mounting portion 131 and the rear mounting portion 132.

Referring to fig. 3, the front mounting portion 131 is symmetrically provided with two first cut surfaces 1311 at an outer side wall thereof. The front mounting portion 131 also has a first catch 1312 circumferentially disposed on an outer wall thereof.

Referring to fig. 3 and 4, the front case 11 is a pen cap structure and has a first receiving cavity 111 with an open rear end. The front case 11 is symmetrically provided with a second tangential surface 112 which is attached to the first tangential surface 1311 in the circumferential direction of the inner wall of the first accommodation chamber 111. The front housing 11 is further provided with four first locking strips 113 at the opening of the first accommodating cavity 111 at intervals in the circumferential direction, and the first locking strips 113 are convex strips arranged in the circumferential direction.

When the front housing 11 is mounted to the front mounting portion 131 of the connector holder 13, the first cut surface 1311 and the second cut surface 112 are attached to each other, so that the front housing 11 and the connector holder 13 are circumferentially locked; the first locking piece 113 is locked in the first locking groove 1312, and the rear end surface of the front housing 11 abuts against the front end surface of the mounting stopper 133.

Referring to fig. 3, the rear mounting portion 132 is symmetrically provided with two third cut surfaces 1321 at the outer side wall thereof. The rear mounting portion 132 is further provided with two first hooks 1322 in circumferential symmetry.

Referring to fig. 3 and 5, the rear housing 12 is a tubular structure penetrating up and down and has a second accommodating cavity 121. The rear housing 12 is symmetrically provided with a fourth cut surface 127 attached to the third cut surface 1321 on the inner wall of the second accommodating cavity 121 in the circumferential direction. The rear housing 12 is symmetrically provided with first bayonets 122 at a front end of the rear housing in a circumferential direction, and the first bayonets 1322 are buckled from inside to outside.

When the rear housing 12 is mounted on the rear mounting portion 132 of the connecting seat 13, the third cut surface 1321 and the fourth cut surface 127 are attached to each other, so that the rear housing 12 and the connecting seat 13 are circumferentially locked; the first buckle 1322 is buckled into the first bayonet 122, and the front end surface of the rear housing 12 abuts against the rear end surface of the installation limiting sheet 133.

Referring to fig. 6, the cartridge assembly includes a syringe sleeve 21 and a cartridge 22.

Referring to fig. 6 and 7, the syringe cover 21 has a mounting cavity 211 for mounting the cartridge 22, and a first mounting port 212 for mounting the cartridge 22 and a first injection port 213 through which an injection end of the cartridge 22 protrudes are formed at a rear end of the syringe cover 21. The needle holder 21 is formed with a first support portion 214 for supporting the cartridge 22 at the front end of the mounting cavity 211.

Referring to fig. 3 and 6, the needle hub 21 is symmetrically provided with two second catches 215 at a rear end thereof in a circumferential direction. The front mounting portion 131 defines a second bayonet 1313 for the second latch 215 to be engaged from inside to outside. The connecting base 13 further has a lower stopper 136 in its inner cavity, which is hollow and against which the rear end of the cassette bottle 22 abuts. When the needle cannula 21 is mounted on the front mounting portion 131, the second latch 215 is latched into the second latch 1313 from inside to outside, and the cartridge 22 is retained between the lower retainer 136 and the first support portion 214, thereby achieving axial locking of the cartridge 22.

Referring to fig. 6 and 7, the needle hub 21 is further provided at a front end thereof with a needle mounting head 216 for mounting a needle assembly. The needle assembly includes a needle tube mounting block 23 that threadably engages needle tube mounting head 216, an injection needle tube 24 mounted on needle tube mounting block 23, a first shield 25 that shields injection needle tube 24, and a second shield 26 that shields needle tube mounting block 23 as a whole.

When the needle tube mounting base 23 is mounted on the needle tube mounting head 216, the rear end of the injection needle tube 24 pierces the rubber seal head of the cartridge bottle 22, and the medical fluid in the cartridge bottle 22 can be discharged from the injection needle tube 24 by pushing the injection piston at the rear end of the cartridge bottle 22. After the needle tube mounting base 23 is detached from the needle tube mounting head 216, the rear end of the injection needle tube 24 is pulled out from the rubber seal head of the cartridge bottle 22, and the rubber seal head of the cartridge bottle 22 can seal the cartridge bottle 22.

Referring to fig. 8 and 9, the protective sheath 3 comprises a fixing protective sheath 31 and an activating protective sheath 32. The fixed protective sleeve 31 is axially slidably mounted on the outside of the needle hub 21. The fixing protection sleeve 31 has two trigger tabs 311 arranged circumferentially symmetrically. The connecting seat 13 has a triggering through slot 134 corresponding to the two triggering insertion pieces 311 one by one and allowing the triggering insertion pieces 311 to axially penetrate through.

Two trigger insertion pieces 311 all have the spacing convex part 312 that is located the connecting seat 13 front side, and spacing convex part 312 can with the front end butt of connecting seat 13 to the displacement volume that fixed protective sheath 31 slided backward on connecting seat 13 is restricted.

Referring to fig. 6 and 8, the needle cannula sleeve 21 is symmetrically provided with two axially arranged first guide strips 217 at the rear end side wall of the needle cannula sleeve, and the fixing protective sleeve 31 is provided with a first guide groove 313 matched with the first guide strips 217 on the trigger insertion sheet 311. The needle cannula sleeve 21 is symmetrically provided with two axially arranged second guide strips 218 at the side wall of the front end of the needle cannula sleeve, and the fixing protective sleeve 31 is provided with a second guide groove 315 matched with the second guide strips 218 at the inner wall of the front end of the fixing protective sleeve 31.

Referring to fig. 8, the fixed protection sleeve 31 is provided with two sets of axial sliding grooves 317 and circumferential sliding grooves 316 on the outer side wall of the front end thereof. Each set of circumferential runners 316 and circumferential runners 316 of circumferential runners 316 are connected to the front end of an axial runner 317.

Referring to fig. 8 and 10, the actuating sheath 32 is fitted over the front end of the fixing sheath 31. The inner wall of the starting protective sleeve 32 is circumferentially and symmetrically provided with two sliding convex parts 321. The sliding protrusion 321 is slidable in the axial slide groove 317 and the circumferential slide groove 316. The actuating sheath 32 is also provided with an inwardly turned limiting flange 322 at its front end.

Referring to fig. 8, the protective sheath 3, which is composed of the fixing protective sheath 31 and the actuating protective sheath 32, has a mounting state and an injection state.

Referring to fig. 8, 10 and 11, when the protecting jacket 3 is in the mounting state, the sliding protrusion 321 of the starting protecting jacket 32 slides in the axial sliding slot 317 of the fixing protecting jacket 31 and abuts against the rear end of the axial sliding slot 317, and the rear end of the starting protecting jacket 32 abuts against the front end of the limiting protrusion 312 of the fixing protecting jacket 31, and the needle mounting head 216 of the needle sleeve 21 is exposed outside the protecting jacket 3, at this time, the patient can conveniently mount the needle assembly on the needle sleeve 21.

Referring to figures 8, 10 and 12, when the shield 3 is in the injecting state, the sliding protrusion 321 of the activating shield 32 slides in the circumferential sliding groove 316 of the retaining shield 31, and the injection needle tube 24 (see figure 7) is hidden in the shield 3, so that the patient does not look directly at the injection needle tube 24, which helps to reduce the fear of the patient to the injection needle tube 24.

Referring to fig. 8 and 10, in order to improve the stability of the protective sheath 3 in the injection state, the fixing protective sheath 31 is provided with an elastic buckle 318 in the circumferential sliding groove 316, so that the sliding protrusion 321 is not easily separated from the circumferential sliding groove 316 after sliding into the circumferential sliding groove 316, and the torque required for the sliding protrusion 321 to slide into the axial sliding groove 317 from the circumferential sliding groove 316 is increased.

The fixed protective sleeve 31 is further provided with a sliding opening 319 on the outer wall thereof for sliding the sliding protrusion 321 into the axial sliding slot 317, and a limiting elastic sheet 3191 is provided at the sliding opening 319 for sliding the sliding protrusion 321 out of the sliding opening 319.

Referring to fig. 2 and 5, the quantitative adjustment mechanism includes a rear bracket 4, a threaded rod 5, a locking sleeve 6, a locking seat 7, a return spring 9, and a tail cap 8. Wherein, the locking sleeve 6, the locking seat 7 and the return spring 9 are arranged in the second accommodating cavity 121 of the rear shell 12 along the front-to-rear direction.

Referring to fig. 13, the rear housing 12 is provided with a mounting protrusion ring 123 at the rear portion of the inner sidewall thereof. The mounting collar 123 is provided at a rear end face thereof with a locking cylinder 124 extending toward a rear end of the rear housing 12 and arranged coaxially with the rear housing 12.

Referring to fig. 13 and 14, rear holder 4 includes a holder sleeve 41, a mounting plate 42, and a driving part 43 in order in a direction away from connecting holder 13. The rear bracket 4 is inserted into the rear housing 12 from the rear end opening of the rear housing 12 such that the bracket collar 41 passes through the mounting boss 123 and is disposed on the front side of the mounting boss 123, the mounting disk 42 abuts on the rear end face of the mounting boss 123, and the driving portion 43 is disposed on the rear side of the mounting boss 123.

The locking cylinder 124 is provided with a third buckle 125 for pressing the mounting disc 42 against the mounting convex ring 123, so that the rear bracket 4 is circumferentially and rotatably mounted on the rear housing 12, and the rear bracket 4 is axially limited with the rear housing 12. The rear end face of the mounting convex ring 123 is further provided with a supporting convex ring 1231 supported on the front end face of the mounting disc 42, which helps to improve the smoothness of the rotation of the rear bracket 4 on the rear housing 12.

Referring to fig. 14, the driving part 43 of the rear bracket 4 has a cylindrical shape. The outer side wall of the driving portion 43 is circumferentially symmetrically provided with two driving screw grooves 431.

Referring to fig. 13 and 15, tail cap 8 is slidably mounted axially to the rear end of rear housing 12. The outer side wall of the tail cap 8 has a fifth cut 811 mating with the fourth cut 127. The outer side wall of the tail cover 8 is also provided with two axially arranged tail end chutes 812 in circumferential symmetry. The rear housing 12 is provided with a rear slider 126 at its inner wall that mates with the rear chute 812.

Referring to fig. 14 and 15, the tail cap 8 further has a driving sleeve 821 sleeved outside the driving portion 43, and an inner wall of the driving sleeve 821 has a driving protrusion 822 matched with the driving thread groove 431, so that the rear bracket 4 can rotate circumferentially during the axial sliding of the tail cap 8.

Referring to fig. 16 to 19, the position of the tail cover 8 when the tail slider 126 abuts against the rear end of the tail chute 812 is defined as a covering station of the tail cover 8, at this time, the tail cover 8 covers the tail opening of the rear housing 12, and the circumferential position of the rear bracket 4 at this time is defined as an initial station. The position of the tail cover 8 when the tail slider 126 abuts against the front end of the tail chute 812 is defined as an extraction station of the tail cover 8, and the circumferential position of the rear bracket 4 at this time is defined as a preparation station.

In the present embodiment, when the tail cap 8 moves from the capping station to the extracting station, the rear bracket 4 rotates by 90 ° and rotates from the initial station to the preparatory station through the engagement of the driving protrusions 822 and the driving screw grooves 431.

Referring to fig. 20, the tail cap 8 is composed of a pen tail sleeve 81 and a pen tail 82. The tail 82 has a tail cover 823 for covering the rear end opening of the tail cap 81, and the driving sleeve 821 is provided at the end of the tail cover 823. The driving sleeve 821 is symmetrically provided with two fourth latches 824 at the rear end thereof in the circumferential direction. The pen tail sleeve 81 is provided with a fourth clamping portion 813 matched with the fourth buckle 824 on the inner wall thereof, and the fourth clamping portion 813 is provided with a guide surface 814 for guiding the fourth buckle 824, so that when the pen tail 82 is inserted from the rear end of the pen tail sleeve 81, the fourth buckle 824 can be clamped on the front side surface of the fourth clamping portion 813 through the guide surface 814.

The outer wall of the drive sleeve 821 is also provided circumferentially with two third guide strips 8211 arranged axially. The rear housing 12 is provided with a third guide slot 1241 at the locking cylinder 124, which is matched with the third guide strip 8211, and helps to improve the axial sliding accuracy of the tail cap 8 on the rear housing 12.

Referring to fig. 16 and 21, the threaded rod 5 is threadedly mounted to the connecting block 13. The threaded rod 5 is symmetrically provided with two screw sections 51 in the circumferential direction, and screw guide grooves 52 are axially formed in the screw sections 51. The threaded rod 5 has a threaded rod sleeve 53 mounted on the front end thereof, and the threaded rod sleeve 53 extends into the opening at the rear end of the cartridge bottle 22 and abuts against the piston of the cartridge bottle 22.

Referring to fig. 21 and 22, connecting section 13 has a coaxially disposed locking sleeve 135. The front end of the locking sleeve 135 has a locking base 1351 that closes the front end opening of the locking sleeve 135. The locking bottom plate 1351 is provided at its center with a threaded through hole 1352 that is threadedly engaged with the threaded rod 5 and axially arranged so that the threaded rod 5 can be axially advanced or axially retracted with respect to the connecting seat 13 when the threaded rod 5 is rotated with respect to the connecting seat 13.

Four groups of locking inserting columns 1353 are uniformly distributed on the inner wall of the locking sleeve 135 of the connecting seat 13 in the circumferential direction. Each set of two locking studs 1353 has two locking studs 1353, with the centerlines of two locking studs 1353 of the same set circumferentially spaced 30 ° and the centerlines of two adjacent locking studs 1353 of a different set axially spaced 60 °. In this embodiment, there is one locking post 1353 of the eight locking posts 1353, and the height of the locking post 1353 is higher than the remaining seven locking posts 1353.

Referring to fig. 16 and 23, the locking sleeve 6 includes a locking portion 61 and a ratchet portion 62 in sequence along a direction away from the connecting seat 13. Wherein the outer diameter of the locking part 61 is smaller than the outer diameter of the ratchet part 62, so that a stepped surface 63 is formed at the connection of the locking part 61 and the ratchet part 62. The trigger inserting piece 311 of the protection sleeve 3 abuts against the stepped surface 63 of the locking sleeve 6 to drive the locking sleeve 6 to axially slide.

Twelve locking slots 611 into which the locking posts 1353 are inserted and which are open at the front end are uniformly arranged on the outer side wall of the locking part 61 in the circumferential direction. The centerlines of adjacent locking slots 611 are circumferentially spaced 30 deg..

Referring to fig. 16, 22 and 23, the position of the locking sleeve 6 when the locking portion 61 abuts against the locking bottom plate 1351 is defined as the locking position of the locking sleeve 6, and when the locking post 1353 is inserted into the locking slot 611, the locking sleeve 6 is axially locked with the connecting seat 13.

Referring to fig. 17, 22 and 23, when the rear end of the position-limiting protrusion 312 of the protective sheath 3 abuts against the connection seat 13, the position of the locking sleeve 6 is defined as an injection position, and at this time, the locking slot 611 is disengaged from the locking post 1353, the locking sleeve 6 and the connection seat 13 are circumferentially unlocked, and the locking sleeve 6 can circumferentially rotate relative to the connection seat 13.

With reference to fig. 21 and 24, the locking sleeve 6 also has a drive through hole 64 which is locked circumferentially with the threaded rod 5. The inner wall of the driving through hole 64 is provided with a guide section 65 engaged with the screw section 51, and the guide section 65 is provided with a guide block 66 engaged with the screw guide groove 52.

Referring to fig. 23 and 25, the locking sleeve 6 and the holder sleeve 41 of the rear holder 4 are engaged by an internal ratchet structure. The inner ratchet structure comprises an elastic ratchet 44 which is axially and slidably arranged on the outer side of the bracket sleeve 41, a ratchet groove 621 which is arranged on the rear end surface of the ratchet part 62 of the locking sleeve 6, and four ratchets 622 which are uniformly arranged on the inner wall of the ratchet groove 621 in the circumferential direction.

Referring to fig. 25, two axially disposed bracket guide slots 411 are symmetrically disposed on the outer wall of the bracket sleeve 41 in the circumferential direction, the elastic ratchet 44 has a through hole for the bracket sleeve 41 to pass through, and a ratchet guide strip 441 capable of sliding along the bracket guide slot 411 is disposed inside the through hole, so that the bracket sleeve 41 and the elastic ratchet 44 are locked in the circumferential direction and are in sliding fit in the axial direction.

Referring to fig. 23 and 25, the elastic ratchet 44 has two elastic pawls 442 symmetrically arranged in the circumferential direction, and the elastic pawls 442 tend to abut against the inner wall of the ratchet groove 621 all the time. When the rear support 4 is in the preparation station, the resilient pawl 442 abuts against the locking end face 6221 of the ratchet 622.

A plurality of side sounding protrusions 623 are further circumferentially spaced on the inner wall of the ratchet groove 621 between adjacent ratchet teeth 622, so that when the elastic pawls 442 circumferentially rotate relative to the inner wall of the ratchet groove 621, a medicine feeding prompt sound of "chuck" can occur. At the same time, the side protrusions 623 can reduce the rotational speed of the elastic ratchet 44 in the ratchet groove 621, which helps to improve the stability of the injection pen for multiple injections during the administration process.

Referring to fig. 2, 5 and 26, the locking seat 7 is installed in the second accommodating cavity 121 of the rear housing 12 and abuts against the rear end of the locking sleeve 6. The outer wall of the locking seat 7 is circumferentially and uniformly provided with four axially arranged fourth guide grooves 71. The inner wall of the second accommodating cavity 121 of the rear housing 12 is provided with fourth guide bars 219 engaged with the four fourth guide grooves 71, so that the locking seat 7 is axially slidably mounted on the rear housing 12.

Referring to fig. 23 and 27, the locking sleeve 6 is provided with a plurality of first sounding protrusions 67 at circumferentially uniform intervals on the rear end surface thereof, and the locking seat 7 is provided with second sounding protrusions 72 at circumferentially uniform intervals on the front end surface thereof, so that when the locking sleeve 6 rotates circumferentially relative to the locking seat 7, an injection sound of "chuck" occurs.

Referring to fig. 2 and 16, one end of the return spring 9 abuts against the front end surface of the mounting convex ring 123 of the rear housing 12, and the other end abuts against the locking seat 7, so that the locking seat 7 always abuts against the rear end of the locking sleeve 6, and the locking sleeve 6 always has a tendency to move axially in the locking position direction.

Referring to fig. 25 and 26, the rear bracket 4 is further provided with two locking teeth 45 circumferentially symmetrically on the outer side wall of the bracket sleeve 41. The front ends of both locking teeth 45 have a first locking surface 451. The locking seat 7 has a locking hook 73, and a rear end of the locking hook 73 has a second locking surface 731.

Referring to figures 16, 25 and 26, when the back support 4 is in the initial position, the first locking surface 451 and the second locking surface 731 face each other and the cannula 24 of the cartridge assembly is still in the holster 3 when the holster 3 is moved up until the first locking surface 451 and the second locking surface 731 abut.

Referring to figures 17, 25 and 26, when the rearward carriage 4 is in the ready position, the first locking surface 451 and the second locking surface 731 are misaligned to allow normal movement of the shield 3 to allow normal penetration of the needle cannula 24 into the patient.

With reference to fig. 1 to 26, an injection pen for multiple quantitative injections according to an embodiment of the present application is implemented as follows:

1. removing front housing 11 from connecting block 13;

2. mounting the needle assembly to the needle mounting head 216 of the needle cannula cover 21 and pulling off the first and

second guards

25 and 26 on the needle assembly;

3. the starting protective cover is pulled out forwards relative to the fixed protective cover and rotates, so that the sliding convex part 321 of the starting protective cover slides into the circumferential arc groove of the fixed protective cover 31, locking is realized, the protective cover 3 is switched into an injection state from an installation state, the injection needle tube is positioned in the protective cover, and fear of a patient to the injection needle tube is reduced;

4. medicine feeding operation: the tail cap 8 is pulled out backwards, so that the tail cap 8 moves from the cap closing station to the pulling station, under the matching of the driving convex part 822 and the driving thread groove 431, in the process that the rear support 4 rotates 90 degrees from the initial station to the preparation station, the elastic pawl 442 of the ratchet seat arranged at the front end of the rear support 4 slides over the side sounding convex part 623 of the inner wall of the ratchet groove 621 to send out the medicine feeding prompting sound of 'chuck', when the rear support 4 is in the preparation station, the elastic pawl 442 slides off from the ratchet 622 to impact on the inner wall of the ratchet groove 621 to send out the prompting sound of medicine feeding completion, and the first locking surface 451 of the rear support 4 and the second locking surface 731 of the locking seat 7 are staggered;

5. the protective cover is abutted against the body surface of a region to be injected on the body of a patient, an injection pen for multiple times of quantitative injection is pressed downwards, the protective cover 3 moves the locking cover 6 from the locking position to the injection position, and the protective cover 3 and the connecting seat 13 are circumferentially unlocked;

6. and (3) injection operation: the tail cover 8 is pressed downwards, the rear support 4 is rotated circumferentially from the preparation station to be gradually reset to an initial station in the process that the tail cover 8 moves from the pulling-out station to the covering station, at the moment, the locking sleeve 6 rotates circumferentially relative to the connecting seat 13 and drives the threaded rod 5 to rotate synchronously, the threaded rod 5 is matched with the threaded through hole 1352 of the connecting seat 13, the threaded rod 5 drives the threaded rod sleeve 53 to feed forwards and extrude the piston of the cassette bottle 22, the liquid medicine in the cassette bottle 22 is injected into the body of a patient, and in the process, as the locking sleeve 6 rotates circumferentially relative to the locking seat 7, the first sounding convex part 67 of the locking sleeve 6 and the second sounding convex part of the locking seat 7 rub against each other to give an injection lifting sound of 'chuck';

7. after the injection is finished, the injection pen for multiple times of quantitative injection is pulled out of the body surface of the patient, and the locking sleeve 6 is reset to the locking position under the action of the reset spring 9.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. An injection pen for multiple quantitative injection is characterized by comprising a shell, a medicine tube component, a protective sleeve (3) and a quantitative adjusting mechanism; the quantitative adjusting mechanism comprises a rear support (4) rotatably mounted on the shell, a threaded rod (5) in threaded fit with the shell, and a locking sleeve (6) which is sleeved on the outer side of the threaded rod (5) and is locked with the threaded rod (5) in the circumferential direction;

the protective sleeve (3) is axially slidably mounted on the shell and abutted against the locking sleeve (6), and the locking sleeve (6) is driven by the protective sleeve (3) to be provided with a locking position which is locked with the shell in the circumferential direction and an injection position which is unlocked with the shell in the circumferential direction;

the rear bracket (4) is rotatably mounted on the shell and is provided with an initial station and a preparation station which are arranged circumferentially; the rear bracket (4) is matched with the locking sleeve (6) through an internal ratchet structure, the rear bracket (4) rotates from the initial station to the preparation station, and the rear bracket (4) does not drive the locking seat (7) to rotate; when the rear support (4) rotates from the preparation station to the initial station, the rear support (4) drives the locking seat (7) to synchronously rotate and drives the threaded rod (5) to feed.

2. A multi-dose injection pen as claimed in claim 1, wherein the inner ratchet structure comprises an elastic ratchet (44) axially slidably mounted on the rear holder (4), a ratchet groove (621) provided in the locking sleeve (6) and for the elastic ratchet (44) to be placed, and a ratchet (622) provided on the inner wall of the ratchet groove (621); the elastic ratchet wheel (44) is locked with the rear bracket (4) in the circumferential direction; the elastic ratchet wheel (44) is provided with an elastic pawl (442) which always tends to be abutted against the inner wall of the ratchet wheel groove (621); when the rear bracket (4) is in the preparation station, the elastic pawl (442) abuts against a locking end face (6221) of the ratchet (622).

3. A multiple dose injection pen as claimed in claim 2, wherein the inner wall of the ratchet groove (621) is further circumferentially spaced apart between adjacent ratchet teeth (622) by a plurality of side sounding protrusions (623).

4. A multiple dose injection pen as claimed in claim 1, wherein the outer wall of the rear holder (4) is provided with a locking tooth (45), and the front end of the locking tooth (45) has a first locking surface (451); a locking seat (7) which is positioned outside the rear bracket (4) and is abutted against the rear end of the locking sleeve (6) is axially and slidably arranged in the shell; the locking seat (7) is provided with a locking hook (73), and the rear end of the locking hook (73) is provided with a second locking surface (731); when the rear bracket (4) is in the initial station, the first locking surface (451) and the second locking surface (731) are opposite, and when the protective sleeve (3) moves upwards until the first locking surface (451) and the second locking surface (731) are abutted, the injection needle tube (24) is in the protective sleeve (3); the first locking surface (451) and the second locking surface (731) are circumferentially staggered when the rear bracket (4) is in the preparation station.

5. A multiple dose injection pen as claimed in claim 4, wherein the dose adjustment mechanism further comprises a return spring (9), the front end of the return spring (9) abuts against the locking seat (7), and the rear end of the return spring (9) abuts against the housing.

6. A multiple dose injection pen as claimed in claim 5, wherein the rear end face of the locking sleeve (6) is circumferentially spaced by a plurality of first noise-emitting protrusions (67); and a plurality of second sound-producing convex parts (72) are circumferentially arranged on the front end surface of the locking seat (7) at intervals.

7. A multiple dose injection pen as claimed in claim 1, wherein the rear holder (4) has a driving part (43), the outer side wall of the driving part (43) has a driving thread groove (431); a tail cover (8) is axially mounted at the tail end of the shell in a sliding manner, and the tail cover (8) is provided with a driving convex part (822) inserted into the driving thread groove (431); the tail cover (8) is provided with a covering station and a pulling station; when the tail cover (8) is in the covering station, the rear bracket (4) is in an initial station; when the tail cover (8) is at the extraction station, the rear bracket (4) is at the preparation station.

8. A multiple metered injection pen as claimed in claim 1, wherein the protective sheath (3) comprises a fixing protective sheath (31) and an activating protective sheath (32); the fixed protective sleeve (31) is provided with an axial sliding groove (317) and a circumferential sliding groove (316), the circumferential sliding groove (316) is connected to the front end of the axial sliding groove (317), and the starting protective sleeve (32) is provided with a sliding convex part (321) capable of sliding in the circumferential sliding groove (316) and the axial sliding groove (317).

9. A multiple dose injection pen as claimed in claim 1, wherein the locking sleeve (6) comprises a ratchet portion (62) and a locking portion (61), the locking portion (61) is circumferentially arranged with a locking socket (611) having an open front end, the housing has a locking post (1353) inserted into the locking socket (611); the locking post (1353) is inserted into the locking slot (611) when the locking sleeve (6) is in the locked position; when the locking sleeve (6) is in the injection position, the locking plug (1353) is disengaged from the locking socket (611).

10. The injection pen of claim 1, wherein the threaded rod (5) has a screw section (51) and a screw guide groove (52) is axially formed on the screw section (51); the locking sleeve (6) is provided with a guide tangent plane (65) matched with the screw tangent plane (51), and a guide block (66) matched with the screw guide groove (52) is arranged on the guide tangent plane (65).