WO2015196420A1

WO2015196420A1 - Syringe cycling switch mechanism

Info

Publication number: WO2015196420A1
Application number: PCT/CN2014/080849
Authority: WO
Inventors: 叶进民
Original assignee: 群康生技股份有限公司
Priority date: 2014-06-26
Filing date: 2014-06-26
Publication date: 2015-12-30

Abstract

A syringe (1) cycling switch mechanism, comprising an inner barrel (40), a bidirectional helical guiding barrel assembly (50) disposed inside of the inner barrel (40), and an injection plunger assembly (90) disposed inside of the bidirectional helical guiding barrel assembly (50). The bidirectional helical guiding barrel assembly (50) comprises an outer helical guiding barrel (51) and an inner helical guiding barrel (52) disposed inside of the outer helical guiding barrel (51). The rear end of the inner helical guiding barrel (52) is connected via a pin joint with the plunger end cover (92) of the injection plunger assembly (90). The outer helical guiding barrel (51) and the inner helical guiding barrel (52) cooperate via a helical guiding groove (514) and a helical guiding block (521), such that the inner helical guiding barrel (52) can rotate and move forward within the outer helical guiding barrel (51). The outer surface of the inner helical guiding barrel (52) is provided with multiple non-return ring threads (522) and an axial guiding groove (523). The inner barrel (40) uses a non-return protrusion (42) thereof to switch position between the non-return ring threads (522) of the inner helical guiding barrel (52) and the axial guiding groove (523). During each operation, the injection plunger assembly (90) can be rapidly pulled back axially. When the injection plunger assembly (90) is pressed axially again, the axial push force is converted into a rotational push force via the bidirectional helical guiding barrel assembly (50) to inject a set dosage of medicine. The cycling switch operation mode achieves simple operation and force conserving.

Description

Syringe cycle switch mechanism

Technical field

The present invention relates to a syringe, and more particularly to a circulation switch mechanism of the syringe. Background technique

In order to cope with the dose injection, count the number of injections, and the limited re-use of the syringe, the currently known syringes are available in both metered and graduated syringes. In the composition of the known metering syringe, a driving mechanism composed of a plurality of driving components is connected to a pusher housing in a syringe housing, thereby installing a medicine bottle in the syringe housing, and the syringe housing is provided in the syringe housing. A needle is attached to the front end, and the needle is connected to the drug bottle. At the time of injection, the needle penetrates into a predetermined part of the human body, and after pressing the rear end of the push rod, the push rod is controlled by the driving part driving the driving mechanism, thereby pushing the piston in the medicine bottle to move a predetermined stroke and outputting the predetermined dose through the needle. Pharmacy.

However, it is known that the metered syringe can achieve the intended purpose of quantitatively outputting the medicament. However, during the operation of the syringe, the syringe is limited by the linkage between the driving components of the driving mechanism, resulting in the syringe. There is a problem of inconvenient operation and laboriousness when injecting a medicament.

Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a circulation switch mechanism for a syringe to solve the inconvenience and laborious problems of the prior art syringe.

The technical solution proposed by the present invention is: providing a circulation switch mechanism of a syringe, comprising: an inner sleeve, the rear end of which forms a check button and a limit retaining edge;

a bidirectional spiral guiding tube set installed in the inner sleeve, the bidirectional spiral guiding tube set comprising an outer spiral conduit and a set of inner spiral conduits disposed in the outer spiral conduit, the outer spiral conduit a spiral tube portion is formed on the inner peripheral wall of the spiral tube portion, and a plurality of spiral guide blocks are disposed on the outer peripheral surface of the front portion of the inner spiral conduit, and the spiral guide block is inserted into the spiral guide groove of the outer spiral conduit. The inner spiral conduit is rotatable in the outer spiral conduit for a predetermined stroke distance, and the outer circumferential surface of the inner spiral conduit is formed with a plurality of backstop rings and is provided with a predetermined length of the axial guide groove, the rear end of the inner sleeve The backstop button can change the position between the backstop ring and the axis guide groove in the rear section of the inner spiral conduit. The stop button extends into the guide groove of the shaft, and the inner spiral guide can move forward in the axial direction. When the check button abuts against the reverse loop of the inner spiral conduit, the inner spiral guide can be prevented from moving linearly toward the front axial direction. The limit retaining edge can limit a position in which the inner spiral conduit moves backward;

An injection pusher set comprising an injection push rod and a set of push rod end caps disposed at a rear end of the injection push rod, the injection push rod being axially slidably disposed in the inner spiral conduit, the push rod end cover being located Outside the rear end of the sleeve, the rear end of the inner spiral conduit is pivotally disposed in the push rod end cover.

In the circulation switch mechanism of the syringe as described above, the reverse spiral of the inner spiral conduit is a single oblique direction, and a unidirectional ratchet groove having a plurality of single oblique ratchets is formed inside the rear portion of the inner spiral conduit. The rear end of the spiral conduit forms a pivoting portion, and the pivoting portion of the inner spiral conduit can extend beyond the rear end of the inner sleeve and pivotally connect the push rod end cover.

In the circulation switch mechanism of the syringe as described above, the front end of the solenoid portion of the outer spiral conduit forms a ring end wall and a pipe end projecting forward from the ring end wall, and the outer peripheral surface of the pipe end forms a plurality of single oblique To the ratchet spring, the inner end wall of the tube end is provided with an axially extending positioning recess.

In the circulation switch mechanism of the syringe as described above, the injection pusher of the injection pusher set includes a rod body and a pressing end portion disposed at the rear end of the rod body, the cross-sectional shape of the rod body is non-circular, and the rod body is formed with a The positioning stopper, the rear end of the rod of the injection pusher having the pressing end protrudes out of the inner spiral duct, and the push rod end cover is sleeved outside the pressing end of the injection push rod.

In the circulation switch mechanism of the syringe as described above, the front end of the inner sleeve is provided with a card slot.

In the circulation switch mechanism of the syringe as described above, the check button at the rear end of the inner sleeve is located inside the limit rib, and the limit rib has a retaining wall at the periphery of the check button; There is a card slot at the front end.

In the circulation switch mechanism of the syringe as described above, the limiting rib at the rear end of the inner sleeve has a notch therein, the check button is located at the notch of the limiting rim; and the front end of the inner sleeve is provided with a card groove.

The beneficial effect that can be achieved by the invention is that the front-opening switch mechanism is applied to the syringe. After the syringe is assembled, after the needle is installed, the injection pusher can be quickly pulled in a straight-back manner. At the injection position, when the injection pusher group is pressed straight, the direct thrust is converted into the rotary injection thrust by the bidirectional spiral guiding tube group, so as to achieve the purpose of quantitative injection of the medicament, and the operation mode of the circulation opening and closing is achieved. Easy and effortless operation.

The circulation switch mechanism of the present invention is further configured by a combination of a check button of the inner sleeve and a reverse ring of the inner spiral guide, so that the injection pusher group must be pulled back to a predetermined position before pressing the injection. The pusher group performs the injection, and the blocking limit function generated by the back end of the inner sleeve and the back-stop ring of the inner spiral surface of the inner spiral guide is not in the middle of the inner spiral guide being pulled out along with the injection pusher group. Because the pressure is retracted by mistake, make sure that the syringe is injected every time. The dose can reach the set injection dose. DRAWINGS

The following drawings are only intended to illustrate and explain the present invention, and do not limit the scope of the invention. 1 is a perspective exploded view of a preferred embodiment of a circulation switch mechanism of a syringe of the present invention.

Fig. 2 is an exploded perspective view showing another perspective of a preferred embodiment of the circulation switch mechanism of the syringe of Fig. 1.

3 is a schematic cross-sectional view showing a preferred embodiment of the cyclic switch mechanism shown in FIGS. 1 and 2.

Figure 4 is a side cross-sectional view showing the position of the A-A section line shown in Figure 3.

Figure 5 is a perspective view showing an embodiment of the preferred embodiment of the circulation switch mechanism shown in Figures 1 and 2 in which the check button is extended into the shaft guide groove.

Fig. 6 is a view showing an embodiment of a preferred embodiment of the cycle switch mechanism shown in Figs. 1 and 2 in which the check button is extended into the reverse ring.

Figure 7 is a perspective view showing another preferred embodiment of the inner sleeve in the circulation switch mechanism of the syringe of the present invention. Figure 8 is a perspective view showing an embodiment of the preferred embodiment of the inner sleeve shown in Figure 7 in which the check button extends into the axial guide groove of the inner spiral conduit.

9 is a perspective exploded view of another preferred embodiment of the screw pusher of the cycle switch mechanism of the present invention and a one-way ratchet, auger and a piston top block in the syringe.

Fig. 10 is a perspective exploded view showing the preferred embodiment of the cyclic switch mechanism shown in Figs. 1 and 2 applied to a syringe and a needle and a needle cover.

Figure 11 is a perspective exploded perspective view showing another preferred embodiment of the cycle switch mechanism of Figure 10 and a portion of the components of the syringe.

Figure 12 is a cross-sectional view showing the syringe of Figure 10 with the needle and needle cover attached thereto.

Figure 13 is a cross-sectional view showing the syringe of Figure 10 without the needle and the needle cover, and the cover is attached. Figure 14 is a side cross-sectional view showing the line position B-B of Figure 13;

Figure 15 is a side cross-sectional view showing the line position C-C of Figure 13;

Fig. 16 is a schematic cross-sectional view showing the syringe of Fig. 10 with the needle cover removed to press the pusher to start the injection. Fig. 17 is a schematic cross-sectional view showing the syringe of Fig. 10 when the pusher is injected with the dosing agent.

Main component label description:

1 syringe 2 drug bottle 2A piston 3 needle

4 needle cover ς Chu

10 outer casing 11 joint end

20 joint collar 21 joint ring

22 sets of ring parts 23 inner ring parts

24 one-way ratchet groove 25 hook

26 inner ring

30 vial case

40 inner sleeve 41 card slot

42 check button 43 limit retaining edge

430 retaining wall section 431 gap

50 bidirectional spiral guiding tube set 51 outer spiral catheter

511 solenoid part 512 ring end wall

513 pipe end 514 spiral guide groove

515 ratchet shrapnel 516 positioning recess

52 inner spiral catheter 521 spiral guide block

522 backstop ring 523 axis guide slot

524 one-way ratchet groove 525 pivot joint

60 screw ring 61 screw hole

62 positioning convex

70 one-way ratchet 71 wheel body

72 single oblique ratchet shrapnel 73 hole

80 screw pusher 81 dose control section

82 limit flange 83 shaft hole

84 piston top block

90 injection putter set 91 injection putter

911 rod body 912 press end

913 positioning block 92 push rod end cover embodiment The technical means adopted by the present invention for achieving the intended purpose of the invention are further described below in conjunction with the drawings and preferred embodiments of the invention.

As shown in FIG. 1 and FIG. 2, a preferred embodiment of the circulation switch mechanism of the syringe of the present invention is disclosed. The cycle switch mechanism includes an inner sleeve 40, a bidirectional spiral guide tube set 50, and an injection push. Rod set 90.

As shown in FIG. 1 and FIG. 2, a rear end of the inner sleeve 40 forms a check button 42 and a limit retaining edge. The front end of the inner sleeve 40 is further provided with a card slot 41. In the preferred embodiment, the limit retaining flange 43 is formed into a full circumference annular body, and the check button 42 is located inside the limit retaining edge 43. The limit retaining edge 43 is outside the check button 42. There is a retaining wall portion 430. Alternatively, as shown in FIG. 7, the limiting rib 43 is formed into an annular body having a notch 431, and the reverse button 42 is located at the notch 431 of the limiting rim 43.

As shown in Figures 1 to 3, the bidirectional helical guiding tube set 50 is mounted in the inner sleeve 40. The bidirectional spiral guiding tube set 50 includes an outer spiral tube 51 and an inner spiral tube 52. The outer spiral tube 51 includes a screw portion 511. The inner peripheral wall of the screw portion 511 forms a spiral guiding groove 514. . The inner spiral conduit 52 is disposed in the outer spiral conduit 51. The inner peripheral surface of the inner spiral conduit 52 is provided with a plurality of spiral guide blocks 521, and the spiral guide blocks 521 are inserted into the spiral guide grooves of the outer spiral conduit 51. 514, the inner spiral conduit 52 can be pressed to rotate in the outer spiral conduit 51 for a predetermined stroke distance.

As shown in FIG. 1 to FIG. 3, in the bidirectional spiral guiding tube set 50, the outer peripheral surface of the rear portion of the inner spiral duct 52 is formed with a plurality of check ring patterns 522 and a predetermined length of the shaft guiding groove 523 is provided. The check button 42 at the rear end of the inner sleeve 40 can be displaced between the check ring 522 and the shaft guide groove 523 of the rear portion of the inner spiral conduit 52. As shown in FIG. 4 and FIG. 5 or FIG. 8, when the check button 42 protrudes into the shaft guiding groove 523, the inner spiral duct 52 can move forward in the axial direction; as shown in FIG. 3 and FIG. When the key 42 abuts against the check ring 522 of the inner spiral duct 52, the inner spiral duct 52 can be prevented from being erroneously pressed and linearly moved in the forward axial direction. The limit retaining rim 43 limits the position of the inner spiral conduit 52 to move backward.

As shown in FIG. 1 to FIG. 3, in the preferred embodiment, the front end of the screw portion 511 of the outer spiral conduit 51 forms a ring end wall 512 and a pipe end 513 protruding forward from the ring end wall 512. A plurality of single oblique ratcheting elastic pieces 515 are formed on the outer peripheral surface of the pipe end 513, and an axially extending positioning concave portion 516 is disposed on the inner wall of the pipe end 513. As shown in FIG. 3 and FIG. 4, the back-circle ring 522 of the inner spiral conduit 52 is a single oblique direction, and a unidirectional ratchet groove 524 having a plurality of single oblique ratchet teeth is formed inside the rear portion of the inner spiral conduit 52. The rear end of the inner spiral conduit 52 forms a pivoting portion 525, and the pivoting portion 525 of the inner spiral conduit 52 can extend beyond the rear end of the inner sleeve 40.

As shown in FIG. 1 to FIG. 3, the injection pusher set 90 includes an injection pusher 91 and a set of pusher end caps 92 disposed at the rear end of the injection pusher 91. The injection pusher 91 is axially slidable. Passing through the inner spiral conduit 52, the push rod end The cover 92 is located outside the rear end of the inner sleeve 40, and the rear end of the inner spiral conduit 52 is pivotally disposed in the push rod end cover 92.

As shown in FIG. 1 to FIG. 3, in the preferred embodiment, the injection pusher 91 of the injection pusher set 90 includes a rod body 911 and a pressing end portion 912 disposed at the rear end of the rod body 911. The rod body 911 can also be formed with a positioning block 913. The rod body 911 of the injection push rod 91 has a rear end of the pressing end portion 912 protruding from the outer spiral duct 52. The push rod end cover 92 is The sleeve is disposed outside the pressing end portion 912 of the injection pusher 91, and the pivoting portion at the rear end of the inner spiral conduit 52 is pivotally disposed in the push rod end cover 92.

The non-circular shape of the rod body 911 of the injection pusher 91 may be a gear shape (as shown in FIG. 1 or FIG. 2) or a polygon, etc., or may have a straight side shape on one side or diametrically opposite sides ( As shown in Figure 9).

When the cycle switch mechanism of the present invention is applied to a syringe, the syringe 1 disclosed in FIG. 10 and FIG. 11 is taken as an example. The combination of the syringe 1 includes an outer casing 10 and a joint collar 20 in addition to the cycle switch mechanism. A vial casing 30, a screw ring 60, a one-way ratchet 70, and a screw pusher 80. Wherein, the engaging collar 20 is disposed inside the outer casing 10, and the vial casing 30 is assembled at the front end of the engaging collar 20, as shown in FIG. 10 and FIG. 11, for providing a medicament. The bottle 2 is fixed therein, and a front end of the vial casing 30 can be provided with a set of 3 needles. As shown in FIG. 10, FIG. 11 and FIG. 13, the circulation switch mechanism is configured such that the inner sleeve 40 is mounted inside the outer casing 10, and the front end of the inner sleeve 40 is assembled to engage the collar 20 and pass through The hook 25 in the engaging collar 20 is engaged with the latching groove 41 at the front end of the inner sleeve 40 to fix the engaging collar 20 and the inner sleeve 40. The outer casing 10 is snap-fitted to the engaging collar. 20, the rear end of the inner sleeve 40 extends out of the outer casing 10, the bidirectional spiral guiding tube set 50 is installed in the inner sleeve 40, and the inner spiral conduit 52 of the bidirectional spiral guiding tube set 50 The rear end extends beyond the rear end of the inner sleeve 40. The threaded ring 60 is mounted in the tube end 513 of the outer spiral conduit 51. The threaded ring 60 is matched with the positioning concave portion 612 of the outer circumferential surface of the outer spiral conduit 51 to make the threaded ring. 60 is combined with the outer spiral conduit 51. The tube end 513 of the outer spiral conduit 51 also extends into the engagement collar 20, as shown in FIG. 14, the ratchet spring 515 of the outer spiral conduit 51 abuts the one-way ratchet in the engagement collar 20, respectively. The single oblique ratchet of the slot 24 allows the outer helical conduit 51 to rotate only in one direction.

As shown in FIGS. 10, 11, and 13, the one-way ratchet 70 is mounted in a one-way ratchet groove 524 of the inner spiral conduit 52. As shown in FIG. 15, the one-way ratchet 70 is The single oblique ratchet spring 72 of the outer peripheral surface of the wheel body 71 meshes with the one-way ratchet of the one-way ratchet groove 524 inside the rear section of the inner spiral conduit 52. As shown in FIGS. 10, 11, and 13, the auger 80 is disposed in the bidirectional helical guiding tube set 50, and the auger 80 is threaded through the threaded dose control section 81 through the threaded ring. Inside the 60, the front end of the dose control section 81 of the auger 80 is provided with a piston top block 84, and the auger 80 is indirectly pushed against the piston 2A in the vial 2 via the piston top block 84. The injection hole 91 in the injection pusher set 90 can be axially slidably inserted through the shaft hole 83 in the screw pusher 80. And inserted in the one-way ratchet 70, the injection pusher 91 fixes the one-way ratchet 70 with a positioning stopper 913 on the rod body thereof, and the injection push rod 91 has a rear end extension of the pressing end portion 912. Outside the inner spiral conduit 52, the push rod end cover 92 is sleeved on the outer side of the pressing end portion 912 of the injection push rod 91, and the pivoting portion at the rear end of the inner spiral conduit 52 is pivotally disposed in the push rod end cover 92 to form a Syringe 1.

Regarding the use of the syringe having the circulation switch mechanism, as shown in FIG. 13, when the medicine bottle 2 is assembled, the medicine bottle 2 has one end of the piston 2A and is inserted into the joint sleeve in a state where the medicine bottle casing 30 is detached. Positioned in the ring 20, the piston top block 84 at the side end of the screw push rod 80 extends into the medicament bottle 2 to abut the piston 2A, and then sets the vial sleeve 30 outside the medicament bottle 2, through the vial sleeve 30 and the sleeve The combination of the rings 20 secures the vial 2 to the syringe 1. As shown in FIG. 13, when the needle 3 and the needle cover 4 are not assembled on the vial casing 30, the medicine bottle 2 is assembled, and the cover 5 is first placed on the vial casing 30. Outside.

When preparing for injection, as shown in Fig. 13, the pen cover 5 is removed, as shown in Fig. 12, the needle 3 and the needle cover 4 are attached, the needle 3 end is inserted into the drug bottle 2, and the needle cover 4 is covered by the needle 3 On the outside, avoid the user being mistakenly stabbed by the needle 3. Next, the injection pusher set 90 is quickly pulled straight back to the predetermined position in the axial direction until the spiral guide block 521 of the outer peripheral surface of the inner spiral conduit 52 is moved to contact the inner end of the inner sleeve 40 at the limit retaining edge 43. Stay stopped. As shown in FIG. 12, during the post-pulling of the injection pusher group 90, the inner spiral conduit 52 is driven to move backward and the inner spiral conduit 51 is idly rotated. The check button 42 at the rear end of the inner sleeve 40 can be inside. The back of the spiral duct 52 is bouncing to generate a sound, as shown in FIG. 6, and is abutted against the limit of the inner loop conduit 52 by the check button 42 at the rear end of the inner sleeve 40. The function of preventing the injection pusher group 90 from being mistakenly pressed to drive the inner spiral conduit 52 to move linearly in the forward direction causes the injection pusher group 90 to be retracted without being crushed during the backward pulling process.

As shown in Fig. 16 and Fig. 17, at the time of injection, the needle cover 4 is removed, the needle 3 is inserted into the predetermined injection site of the human body, and the injection pusher group 90 is pressed to start the injection, wherein the injection pusher group is pressed by the straight forward direction. The action of 90, and pushing the inner spiral conduit 52 via the pusher end cap 92, wherein, as shown in FIG. 5, the check button 42 at the rear end of the inner sleeve 40 enters the axial guide groove 523 of the inner spiral conduit 52, making the inner spiral The duct 52 can be moved straight forward with the injection pusher set 90, as shown in FIG. 16 and FIG. 17, while the outer spiral guide 51 is driven by the spiral guide block 521 of the outer peripheral surface of the inner spiral conduit 52 to rotate in a fixed direction until The inner spiral conduit 52 is traveled a distance away from the outer spiral conduit 51, and the injection pusher set 90 extends into the outer casing 10 to close. When the outer spiral conduit 51 rotates in the forward direction, the screw ring 60 is rotated together, and the screw push rod 80 is rotationally driven to rotate forward through the screw ring 60 to apply a thrust to the piston 2A in the drug bottle 2, so that the drug bottle 2 is rotated. The medicine inside is output through the needle 3.

As shown in FIGS. 16 and 17, in the foregoing, it is a cooperation of the spiral guide groove 514 which has a predetermined stroke distance inside the outer spiral conduit 51 and the spiral guide block 521 of the outer peripheral surface of the inner spiral conduit 52, and is mounted on the outer spiral conduit. 51 The screwing ring 60 is screwed into the screw push rod 80 so that the pressing push rod group 90 can only push the distance of the predetermined stroke straight, and the screw ring 60 is driven to drive the screw push rod 80 to rotate one revolution. That is, the stop is performed, and the drug bottle 2 is controlled to output the set injection dose. On the other hand, by the combination of the helical guide groove 514 of the outer spiral conduit 51 and the large pitch stroke of the spiral guide block 521 of the inner spiral conduit 52, the screw hole of the screw ring 60 and the thread of the screw push rod 80 are small pitch strokes. The combined configuration, and the injection thrust of the large stroke rotary thrust to the small stroke rotation, makes the syringe 1 have a labor-saving effect during use.

As shown in FIG. 12, after the injection is completed, the needle cover 4 is first sleeved on the outer side of the needle 3, and then the needle 3 and the needle cover 4 are pulled out from the syringe 1, and the pen cover 5 is closed to the vial cover of the syringe 1. The outside of the shell 30 ensures that the next needle can be replaced with a new needle.

As shown in FIG. 16 and FIG. 17, when the syringe 1 is in use, the unidirectional ratchet 70, the bidirectional spiral guiding tube set 50, the screwing ring 60 and the auger 80 are coupled by the injection pusher set 90. The mechanism is invented so that it can be easily opened and closed by the user during the operation of each quantitative injection. Further, the number of threads and the pitch of the outer peripheral surface of the dose control section 81 of the screw pusher 80 are set according to the drug volume in the vial 2, and the injection number and the injection dose are set, so that the syringe 1 has the functions of fixed dose injection and automatic counting use. . When the number of uses of the syringe 1 equipped with the vial 2 reaches a predetermined number of times, the medicine in the vial 2 is just used up, and at this time, the syringe 1 is discarded to prevent the syringe 1 from being overused.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention, any technology that is familiar with the present technology. A person skilled in the art can make some modifications or modifications to equivalent embodiments by using the above-disclosed technical contents without departing from the technical scope of the present invention. Technical simplifications Any simple modifications, equivalent changes and modifications made to the above embodiments are still within the scope of the technical solutions of the present invention.

Claims

Claim

A circulation switch mechanism for a syringe, characterized in that it comprises:

An inner sleeve, the rear end of which forms a check button and a limit stop;

a bidirectional spiral guiding tube set installed in the inner sleeve, the bidirectional spiral guiding tube set comprising an outer spiral conduit and a set of inner spiral conduits disposed in the outer spiral conduit, the outer spiral conduit a spiral tube portion is formed on the inner peripheral wall of the spiral tube portion, and a plurality of spiral guide blocks are disposed on the outer peripheral surface of the front portion of the inner spiral conduit, and the spiral guide block is inserted into the spiral guide groove of the outer spiral conduit. The inner spiral conduit is rotatable in the outer spiral conduit for a predetermined stroke distance, and the outer circumferential surface of the inner spiral conduit is formed with a plurality of backstop rings and is provided with a predetermined length of the axial guide groove, the rear end of the inner sleeve The backstop button can change the position between the backstop ring and the axis guide groove in the rear section of the inner spiral conduit. When the check button protrudes into the shaft guide groove, the inner spiral guide can move forward in the axial direction, when the check button Resisting the back-circle of the inner spiral conduit prevents the inner spiral conduit from moving linearly toward the front axial direction, and the limit retaining edge can limit the position of the inner spiral conduit to move backward;

2 . The cyclic switch mechanism of claim 1 , wherein the inner spiral conduit has a single oblique direction, and the inner spiral conduit has a plurality of single oblique ratchets formed inside the rear portion of the inner spiral conduit. The one-way ratchet groove, the rear end of the inner spiral conduit forms a pivoting portion, and the pivoting portion of the inner spiral conduit can extend beyond the rear end of the inner sleeve and pivotally push the push rod end rm 0

3. The cycle switch mechanism of a syringe according to claim 1, wherein a front end of the solenoid portion of the outer spiral conduit forms a ring end wall and a pipe end projecting forward from the ring end wall, the tube The outer peripheral surface of the end is formed with a plurality of single oblique ratchet springs, and the inner wall of the tube end is provided with an axially extending positioning recess.

4. The cycle switch mechanism of a syringe according to claim 2, wherein a front end of the solenoid portion of the outer spiral conduit forms a ring end wall and a pipe end projecting forward from the ring end wall, the tube The outer peripheral surface of the end is formed with a plurality of single oblique ratchet springs, and the inner wall of the tube end is provided with an axially extending positioning recess.

The circulation switch mechanism of a syringe according to any one of claims 1 to 4, wherein a front end of the inner sleeve is provided with a card slot.

The cycle switch mechanism of the syringe according to any one of claims 1 to 4, wherein the injection pusher of the injection pusher set comprises a rod body and a pressing end portion disposed at a rear end of the rod body, the rod body The cross-sectional shape is non-circular, and a positioning stopper is formed on the rod body, and a rear end of the rod body of the injection push rod having a pressing end portion protrudes from the inner screw Outside the rotary duct, the push rod end cover is sleeved outside the pressing end of the injection push rod.

7. The circulation switch mechanism of a syringe according to claim 6, wherein a front end of the inner sleeve is provided with a card slot.

The cycle switch mechanism of the syringe according to claim 6, wherein the backstop button of the rear end of the inner sleeve is located inside the limit retaining edge, and the limit retaining edge has a block at the periphery of the check button a wall portion; a front end of the inner sleeve is provided with a card slot.

The cycle switch mechanism of the syringe according to claim 6, wherein the limit retaining edge of the rear end of the inner sleeve has a notch therein, and the check button is located at a notch of the limit retaining edge; A front end of the inner sleeve is provided with a card slot.