TWM447779U - Quantitative syringe - Google Patents

Description

Metering syringe

This creation relates to a syringe, and more particularly to a metered syringe that can display an injection dose value.

At present, such as insulin injection, small needle beauty, etc., all use a small syringe to draw a predetermined dose of the drug from the drug bottle containing the injection drug, and then inject the drug into the human body through the needle at the front end of the syringe. .

When the conventional syringe is used, the components are all in contact with the medicament, and based on the safety of the injection, after the syringe is used, all the components of the entire syringe need to be discarded, so the cost of the patient is high in the syringe. , resulting in a heavy burden of treatment, and the amount of waste used in the syringe after use.

Furthermore, when the user uses an existing syringe syringe to apply the injecting drug to the human body, the syringe is lacking in the easily injectable drug amount display mechanism, which causes inconvenience for the user to use the syringe.

The main purpose of this creation is to provide a metered syringe that is created to improve the shortcomings of existing syringes that do not directly display the injected dose value.

In order to achieve the foregoing disclosure, the metered syringe proposed by the present invention comprises: an injection sleeve set comprising a hollow first sleeve and a hollow a second sleeve, the first sleeve is for providing a medicine bottle, the first sleeve has a needle connecting end at one end, and the needle connecting end portion is provided for providing an injection needle set thereon, the first sleeve The other end has a joint end portion, and the second sleeve comprises a sleeve portion and an extension tube portion that is connected to one end of the sleeve portion, and the joint portion of the first sleeve is detachably assembled with the sleeve portion a sleeve window is disposed on the sleeve portion of the second sleeve; an injection pusher is movably mounted in the set of the injection sleeve and can connect the piston in the medicament bottle, the injection pusher The utility model comprises a rod body and an operating member, wherein one end of the rod body is a driving portion, and the other end of the shaft body is a rod connecting portion, and the rod connecting portion of the rod body extends out of the second sleeve, and the operating member is located a second sleeve outer connecting rod connecting portion, the rod body forming a plurality of driving thread segments on an outer peripheral surface of the driving portion, the plurality of driving thread segments being successively arranged along the axial direction of the rod body, the driving thread segment comprising a plurality of adjacent juxtaposed Threaded bar, the plurality of threaded bars in the adjacent drive thread segments are forward snails And a dose display wheel ring comprising a ring body disposed in the second sleeve and sleeved outside the driving portion of the rod of the injection push rod, the outer circumferential ring of the ring a plurality of dose values, the dose value corresponding to the display window, the peripheral surface of the ring body forming a plurality of passive threads in a forward spiral, and the passive thread meshes with a portion of the driving thread segment of the shaft driving portion, thereby injecting the push rod into the injection When the sleeve group moves linearly, the rod driven by the rod of the injection push rod drives the ring body to rotate and presents the dose value in the display window.

The syringe can be used for the purpose of repeating the multiple use of the injection sleeve, the injection push rod and the dose display wheel, and the syringe further enables the dose to be installed inside the injection sleeve group. The outer peripheral surface of the ring showing the ring is provided with a dose value that can be displayed through the injection sleeve set window And forming a plurality of passive helical threads in the inner portion of the ring body, and forming a plurality of driving thread segments arranged in the axial direction on the outer peripheral surface of the driving portion of the injection pusher rod passing through the ring body to drive the forward spiral of the thread segment The threaded thread rod meshes with the passive thread in the ring body, so that the metering syringe is provided with the medicine bottle in the injection sleeve group, and after the injection needle is connected, the injection needle is used in the process of human body injection. When the injection sleeve group moves linearly to push the medicine in the medicine bottle, the rod of the injection push rod drives the thread segment to drive the ring body to rotate and display the dose value in the display window, so that the user can easily interpret the injected dose. .

As shown in Fig. 1, the inventive metered syringe is used to provide a disposable medicine bottle 1 and a disposable injection needle 2 for use as a medicament injection. The disposable medicine bottle 1 comprises a transparent bottle body containing an injection medicament, and the bottle body is sealed at one end to form a closed end cover, and the other end of the bottle body is provided with airtight contact with the inner wall of the bottle body and the shaft To the moving piston 1A; the disposable injection needle 2 is mainly disposed in a set of joints, and an injection needle having a pinhole therein is fixed, and the injection needle extends out of the sleeve portion into an injection section for socketing The section in the section is a puncture section, and the puncture section is used to puncture the closed lid of the medicament bottle 1 and protrude into the medicament bottle 1.

As shown in FIG. 1 , the composition of the present metered syringe mainly comprises: an injection sleeve set 3, an injection push rod 4 and a dose display wheel ring 5, or further comprises a cover 6, wherein: 1 and 2, the injection sleeve set 3 includes a first sleeve 31 and a second sleeve 32. The first sleeve 31 is a hollow body that is axially penetrated inside. Providing a medicament bottle 1 therein, wherein the A sleeve 31 has a needle connecting end portion 311 at one end and an engaging end portion 312 at the other end. As shown in FIG. 5, the needle connecting end portion 311 is used to provide the medicament bottle 1 with one end of the closed lid body. Wherein, the sleeve portion of the injection needle 2 is provided, and the injection needle 2 can be inserted into the medicament bottle 1. In the preferred embodiment, the side end of the engaging end portion 312 of the first sleeve 31 is formed with a plurality of spaced apart hooks 313, and the card hook 313 and the second sleeve 32 are combined by the snapping. The manners are detachably assembled together, and the outer peripheral surface of the engaging end portion 312 forms an outwardly projecting fin portion 315.

As shown in FIG. 1 and FIG. 2, the second sleeve 32 is a hollow body that is axially penetrated inside. The second sleeve 32 includes a set of connecting portions 321 and a connecting end of the sleeve portion 321 . An extension tube portion 322, the detachable assembly of the sleeve portion 321 is coupled to the joint end portion 312 of the first sleeve 31, and the injection sleeve set 3 combined by the first sleeve 31 and the second sleeve 32 will The drug bottle 1 is fixed therein.

As shown in FIG. 1 , FIG. 4 and FIG. 5 , the second sleeve 32 defines a partition portion 323 between the sleeve portion 321 and the extension tube portion 322 and has a shaft tube passing through the partition portion 323 . The partition 323 partitions the inner space of the second sleeve 32 into an assembly space in the socket portion 321 and an active space in the extension tube portion 322, and provides the medicament bottle with the partition portion 323. At the abutting portion, the assembly space of the second sleeve 32 forms a fitting opening at the outer end of the sleeve portion 321 , and the sleeve portion 321 forms a snap flange 326 adjacent to the fitting opening in the movable space. The outer peripheral wall of the sleeve portion 321 is formed with a plurality of pressing elastic pieces 327, and a groove is formed around the pressing elastic piece 327 so that one end of the pressing elastic piece 327 adjacent to the locking flange 326 is a free end and has elasticity for radial movement and recovery. set The engaging end portion 312 of the sleeve 31 is inserted into the sleeve portion 321 of the second sleeve 32. The hook 313 is hooked to the locking flange 326, and can be pushed away from the locking flange 326 by the pressing elastic piece 327. The engaging end portion 312 of the first sleeve 31 can be disassembled from the sleeve portion 321 of the second sleeve 32, and the second sleeve 32 is provided at the sleeve portion 321 at least one portion extending from the outer peripheral surface to the inner fitting space. Display window 328. In the preferred embodiment, display window 328 is located on the side of pressing elastic piece 327.

In the second sleeve 32, the shaft tube portion passing through the partition portion 323 includes a first section located in the assembly space and a second section located in the movable space, and the second sleeve 32 is in the shaft tube portion. A ring portion 329 connecting the partition portion 323 is formed on the periphery of the first portion 324, and the shaft tube portion 324 forms an axial hole penetrating through the central hole, and the end portion of the second portion of the shaft tube portion 324 is formed in a radial direction. The elastic piece portion 3241 has a resilient abutting protrusion 3245 formed at the end of the elastic piece portion 3241, and a single oblique inclined surface is formed on the abutting protrusion 3245, and the first section of the shaft tube portion 324 is peripherally The inner wall of the ring portion 329 is formed with one or a plurality of end bumps 3291. In the preferred embodiment, the outer peripheral surface of the first portion of the shaft tube portion 324 has two diametrically opposite limit stops 3242, and the limit block The block 3242 has a spacing from the partition portion 323. The second sleeve 32 can form a plurality of axially extending and spaced apart ribs 3243 in the inner wall of the extending tube portion 322. Two radial corresponding guiding lugs 3244 are also formed on the wall.

As shown in FIG. 1, the injection pusher 4 is movably mounted in the first sleeve 31 and the second sleeve 32, and is connected to the piston 1A of the medicament bottle 1, and the injection pusher 4 includes a rod 40 and an operating member 41, wherein: As shown in FIG. 1 and FIG. 3, one end of the rod body 40 in the axial direction is a driving portion 401, and the other end of the rod body 40 in the axial direction is a rod connecting portion 402, and can directly abut the medicine bottle 1 with the driving portion 401. The inner piston 1A, or the driving portion 401 is combined with a circular rod end block 403, the rod end block 403 abuts the piston 1A of the medicament bottle 1, and the rod connecting portion 402 of the rod 40 extends out of the injection sleeve Outside the second sleeve 32 of the group 3, the rod body 40 forms a plurality of driving thread segments 404 on the outer peripheral surface of the driving portion 401, and the driving thread segments 404 are arranged at least in the axial direction along the axial direction of the rod body 40. The driving thread segment 404 includes a plurality of adjacent parallel and forward spiral threaded strips, and the plurality of threaded strips in the adjacent driving thread segments 404 are in a forward spiral connection, and the number of the driving thread segments 404 is based on the actual installation of the medicament The bottle size is adjusted. As shown in FIG. 3 and FIG. 6, in the preferred embodiment, the driving portion 401 of the rod body 40 forms two rows of symmetrical radial segments 18 of the driving thread segments 404.

As shown in FIG. 1, the operating member 41 is assembled to the end of the rod connecting portion 402 of the rod body 40 extending outside the second sleeve 32.

As shown in FIG. 1 , FIG. 4 , FIG. 8 and FIG. 9 , in the preferred embodiment, the injection pusher 4 further includes a sliding sleeve 42 . The sliding sleeve 42 includes a sleeve 421 and a sleeve formed on the sleeve. a fixing portion 422 at one end of the 421, the sleeve 421 is movably inserted into the movable space of the extending tube portion 322 of the second sleeve 32 and sleeved outside the shaft tube portion 324, and the second sleeve 32 is The plurality of ribs 3243 formed in the extension tube portion 322 can contact the outer circumferential surface of the sliding sleeve 42, and the fixing portion 422 can be coupled to the rod connecting portion 402 of the rod body 40 and the operating member 41 to be linked together.

The outer circumferential surface of the sleeve body 421 is distributed to form a plurality of guiding grooves 423 each having an axially extending straight groove portion and a spiral groove portion. The straight groove portion has a first groove end and a second groove end respectively located at two axial ends, and the spiral groove portion is respectively located between two adjacent straight groove portions, and the groove is from the two adjacent straight groove portions. In the preferred embodiment, the outer circumferential surface of the sleeve 421 forms a second guiding groove 423, and the two guiding grooves 423 are straight. The groove portions are arranged in a radial direction, and the spiral groove portion is spirally connected by 180 degrees to be connected between the two adjacent straight groove portions. As shown in FIG. 1 , FIG. 8 and FIG. 9 , the sliding sleeve 42 is provided with two guiding grooves of the inner wall of the extending pipe portion 322 of the second sleeve 32 by two guiding grooves 423 on the sleeve body 421 . The block 3244 extends therein, whereby when the guiding protrusion 3244 is located at the straight groove portion of the guiding groove 423 of the sliding sleeve 42, the injection push rod 4 can axially push the piston 1A in the medicine bottle 1 forward; When the guiding protrusion 3244 is moved to the spiral groove portion of the guiding groove 423, the injection push rod 4 can be moved in the reverse direction in a spiral manner, and the operation convenience is relatively labor-saving.

As shown in FIG. 1 , FIG. 8 and FIG. 9 , in the preferred embodiment, the inner circumferential surface of the sliding sleeve 42 is formed with a plurality of oblique grooves 426 , and the second sleeve 32 is provided with the shaft portion 324 . The abutting protrusion 3245 at the end of the elastic piece 3241 abuts against the inclined groove portion 426. The sliding sleeve 42 is connected to the inner end of the operating member 41 to form an annular baffle 424 having an inner hole and a bottom hole. The connecting portion 425 extending toward the distal end of the fixing portion 422 forms an assembly space between the connecting portion 425 and the inner wall of the fixing portion 422, and the peripheral wall of the connecting portion 425 is provided with a plurality of slits extending axially from the end thereof. The connecting portion 425 has the elasticity of expansion and recovery. The fixing portion 422 of the sliding sleeve 42 forms a plurality of engaging holes 4221 adjacent to the annular baffle 424. The engaging hole 4221 communicates with the assembling space, and the rod 40 is poled. Forming a radial convex on the connecting portion 402 The protruding ring flange 405, the end of the rod connecting portion 402 forms a flange 406, and the rod body 40 extends into the sliding sleeve 42. The rod connecting portion 402 of the rod body 40 is correspondingly inserted into the connecting portion 425 in the sliding sleeve 42. The ring flange 405 abuts against the side end of the annular baffle 424, and the flange 406 abuts against the end of the joint portion 425 to be combined.

As shown in FIG. 1 , FIG. 5 and FIG. 8 , the operating member 41 is located on the outer side of the second sleeve 32 and the rod connecting portion 402 of the rod body 40 and the sliding sleeve 42 . The operating member 41 includes a knob portion 411 and The sleeve portion 412 is formed in the sleeve portion 411 and extends in the axial direction. The end of the sleeve portion 412 forms a plurality of fixing hooks 413. The operating member 41 is sleeved on the fixing portion 422 of the sliding sleeve 42 by the knob portion 411. The outer side of the sleeve portion 412 extends into the assembly space in the fastening portion 422 and is sleeved on the outside of the connection portion 425, and the plurality of fixing hooks 413 are respectively fastened to the fastening holes of the fixing portion 422 of the sliding sleeve 42. In 4221, the operating member 41, the sliding sleeve 42, and the rod body 40 are fixed together, and the outer peripheral surface of the knob portion 411 of the operating member 41 can be formed with a concave-convex sliding portion.

In the preferred embodiment shown in FIG. 1, the side ends of the engaging end portions 312 of the first sleeve 31 may further form a plurality of alignment convex portions, and the alignment convex portions are interlaced with the hooks 313. Arranging; the sleeve portion 321 of the second sleeve 32 can further form a plurality of alignment recesses corresponding to the alignment protrusions at the mounting opening thereof, by the concave and convex portions of the alignment protrusions and the alignment recesses, The joint end portion 312 of the first sleeve 31 is firmly assembled with the sleeve portion 321 of the second sleeve 32.

As shown in FIG. 1 and FIG. 3 , the dose display wheel ring 5 includes a ring body 50 that is mounted in the assembly space of the second sleeve 32 and is sleeved on the rod of the injection push rod 4 . Outside the driving portion 401 of the body 40, the outer circumferential surface of the ring body 50 is arranged in a plurality of dose values (for example, 0, 5, 10, 15, 20) 25, wherein 5 represents 0.5 ml, and so on, the dose value corresponds to the display window 328, and the inner peripheral surface of the ring body 50 forms a plurality of passive threads 51, the passive threads 51 are forward spirals, and the passive threads 51 When the partial driving screw thread 404 of the shaft driving portion 401 is engaged, when the injection push rod 4 is linearly moved in the injection sleeve group 3, each driving thread portion 404 can be used to rotate the ring body 50.

As shown in FIG. 1 , FIG. 3 , FIG. 5 and FIG. 7 , in the above-mentioned dose display wheel ring 5 , a plurality of hook pieces 52 are protruded from the ring body 50 toward the side end of the partition plate portion 323 . The sheets 52 are arranged at equal intervals and are hooked by the hooks 52 against the limit stops 3242 so that the dose display wheel 5 can only rotate at a fixed point, and the end bumps 3291 of the second sleeve 32 are abutted. Relying on the gap between the ends of the two adjacent hooks 52, and thereby having the function of the scale, for example, the side end of the ring body 50 has 36 hook pieces 52, that is, the interval between each two hook pieces 52 is 10 degrees. In order to facilitate the setting of the injection stroke.

As shown in FIG. 1 , the cover 6 includes a cover body, one end of the cover body is an open end, and the other end is a closed end, and is sleeved on the outside of the first sleeve 31 of the injection needle and the injection sleeve set 3 . In the preferred embodiment, the cover 6 can form a strip-shaped clamping portion on the side of the cover body, so that the cover 6 can be gripped by the user. The part is clamped on the object.

In the preferred embodiment of the present invention, as shown in FIG. 1 and FIG. 5 and FIG. 8, a pharmaceutical bottle 1 containing a fixed dose of a medicament for injection is attached to the first sleeve 31 and the second sleeve. In the injection sleeve set 3 composed of the cylinder 32, the rod end block 403 of the injection body 4 of the injection pusher 4 disposed in the second sleeve 32 abuts against the piston 1A in the medicament bottle 1, and then Will note The needle needle 2 is sleeved on the needle connecting end portion 311 of the injection sleeve group 3, and the needle body puncture segment of the injection needle 2 is pierced through the closed lid of the medicine bottle 1 and protrudes into the medicine bottle 1 to provide the user with an injection. The medicament bottle can also be taken out from the metering syringe after use, and the metering syringe can be used repeatedly.

When the preferred embodiment of the metering syringe injects a medicament on a human body, the user pushes the injection pusher 4 to push the piston 1A in the medicament bottle 1, and the medicament in the medicament bottle 1 enters the human body through the injection needle, and uses the same. The driving thread segment 404 on the rod body 40 cooperates with the passive thread 51 on the inner surface of the ring body 50 of the dose display wheel ring 5, and the dose display wheel ring 5 is rotated during the straightening process of the injection push rod 4, as shown in the figure. 9 and FIG. 10, the dose value of the outer peripheral surface of the ring body 50 is presented at the display window 328 of the second sleeve 32, so that the user can directly see the dose of the injection.

When the injecting medicament of the metering syringe in the medicament bottle 1 is used, it can be pulled out in the opposite direction by the rotation of the injection push rod 4, and at this time, the inner surface of the ring body 50 of the dose display wheel ring 5 is passively threaded 51 and injected. The outer peripheral surface driving thread segment 404 of the push rod 4 is a forward thread, so that the rod 40 of the injection push rod 4 is slid in the ring body 50 of the dose display wheel ring 5, and the dose display wheel ring 5 does not rotate. .

As can be seen from the above description, in the metering syringe proposed in the present invention, only the needle relating to the use of the safety needle and the medicine for the fixed-dose injection medicine is a disposable member, and the other combined injection sleeve group and injection The push rod and the cover can be reused many times, and the metered syringe can directly display the dose value of the injection in the injection sleeve group during use, so that the user can control the injected medicament.

1‧‧‧pharmaceutical bottles

1A‧‧‧Piston

2‧‧‧Injection needle

3‧‧‧Injection sleeve set

31‧‧‧First sleeve

311‧‧‧Needle connection end

312‧‧‧ joint end

313‧‧‧ hook

315‧‧‧Face Department

32‧‧‧Second sleeve

321‧‧‧Settings

322‧‧‧Extensions

323‧‧‧Parts

324‧‧‧ shaft tube department

3241‧‧‧Shrap Department

3242‧‧‧ Limit Stop

3243‧‧‧ ribs

3244‧‧‧Guiding bumps

3245‧‧‧Abutment bumps

326‧‧‧Card flange

327‧‧‧ Pressing shrapnel

328‧‧‧ display window

329‧‧‧ Ring Department

3291‧‧‧End bumps

4‧‧‧Injection putter

40‧‧‧ rod body

401‧‧‧ Drive Department

402‧‧‧ rod connection

403‧‧‧ rod end block

404‧‧‧Drive thread segment

405‧‧‧ ring flange

406‧‧‧Flange

41‧‧‧Operating parts

411‧‧‧ knob section

412‧‧‧Set of joint management department

413‧‧‧Fixed hook

42‧‧‧Sleeve

421‧‧‧ Socket

422‧‧‧Fixed Department

4221‧‧‧ card hole

423‧‧ ‧ guide slot

424‧‧‧ ring baffle

425‧‧‧Receipt Department

426‧‧‧ chute

5‧‧‧Dose display wheel

50‧‧‧ ring body

51‧‧‧ Passive thread

52‧‧‧hook

6‧‧‧ Cover

1 is a perspective exploded view of a preferred embodiment of the present metered syringe and a medicament bottle and an injection needle.

2 is a schematic view showing the combination of a preferred embodiment of the metering syringe of FIG. 1 in combination with a medicament bottle and an injection needle.

3 is a perspective exploded view of the plunger of the injection pusher and the dose display wheel in the preferred embodiment of the metering injector of FIG. 1.

4 is a perspective exploded cross-sectional view of the second sleeve and the sliding sleeve in the preferred embodiment of the metering injector of FIG. 1.

Figure 5 is a schematic cross-sectional view showing a preferred embodiment of the metering syringe of Figure 1 in combination with a medicament bottle and an injection needle.

Figure 6 is a schematic cross-sectional view showing the position of the cut surface line 6-6 in Figure 5.

Figure 7 is a schematic cross-sectional view showing the position of the face line 7-7 in Figure 5.

Figure 8 is a schematic cross-sectional view showing a preferred embodiment of the metering syringe of Figure 1 in combination with another viewing angle of the medicament bottle and the injection needle.

Figure 9 is a schematic cross-sectional view showing the position of the face line 9-9 in Figure 8.

Figure 10 is a reference view (I) of the preferred embodiment of the metering syringe of Figure 1 in combination with the use of the medicament bottle and the injection needle.

Figure 11 is a view showing the state of use of the preferred embodiment of the metered syringe of Figure 1 in combination with the vial and the injection needle (Figure 2).

1‧‧‧pharmaceutical bottles

1A‧‧‧Piston

2‧‧‧Injection needle

3‧‧‧Injection sleeve set

31‧‧‧First sleeve

311‧‧‧Needle connection end

312‧‧‧ joint end

313‧‧‧ hook

315‧‧‧Face Department

32‧‧‧Second sleeve

321‧‧‧Settings

322‧‧‧Extensions

324‧‧‧ shaft tube department

3244‧‧‧Guiding bumps

3245‧‧‧Abutment bumps

327‧‧‧ Pressing shrapnel

328‧‧‧ display window

4‧‧‧Injection putter

40‧‧‧ rod body

401‧‧‧ Drive Department

402‧‧‧ rod connection

403‧‧‧ rod end block

404‧‧‧Drive thread segment

405‧‧‧ ring flange

406‧‧‧Flange

41‧‧‧Operating parts

411‧‧‧ knob section

412‧‧‧Set of joint management department

413‧‧‧Fixed hook

42‧‧‧Sleeve

421‧‧‧ Socket

422‧‧‧Fixed Department

4221‧‧‧ card hole

423‧‧ ‧ guide slot

426‧‧‧ chute

5‧‧‧Dose display wheel

50‧‧‧ ring body

51‧‧‧ Passive thread

52‧‧‧hook

6‧‧‧ Cover

Claims (7)

A metered syringe includes: an injection sleeve set including a hollow first sleeve and a hollow second sleeve, the first sleeve is for providing a medicament bottle, the first sleeve One end has a needle connecting end portion, the needle connecting end portion is for providing an injection needle set thereon, the other end of the first sleeve has an engaging end portion, and the second sleeve comprises a set of connecting portions and a connecting sleeve An extension pipe portion at one end of the pipe joint portion, and a joint end portion of the first sleeve is detachably assembled with the sleeve pipe portion, and a display window is arranged on the sleeve pipe portion of the second sleeve; an injection pusher is movable The grounding device is installed in the injection sleeve group and can be connected to the piston in the medicament bottle. The injection push rod comprises a rod body and an operating member, and the rod body has a driving portion at one end of the rod body. The other end of the axial direction is a rod connecting portion, the rod connecting portion of the rod body extends out of the second sleeve, and the operating member is located at the outer connecting rod connecting portion of the second sleeve, and the rod body forms a plurality of driving threads on the outer peripheral surface of the driving portion. a segment driving the thread segments sequentially along the axial direction of the rod body, The movable thread segment comprises a plurality of adjacent parallel threaded strips, wherein the plurality of threaded strips in the adjacent drive thread segments are in a forward spiral connection; and a dose display wheel ring comprises a ring body, the ring body being mounted on the second set The inside of the cylinder is sleeved on the outer side of the driving portion of the rod of the injection pusher. The outer peripheral surface of the ring is arranged in a plurality of dose values, and the dose value corresponds to the display window, and the circumferential surface of the ring is formed into a plurality of passive spirals. Threading, and the passive thread meshes with a portion of the driving thread segment of the shaft driving portion, so that when the injection push rod moves linearly in the injection sleeve group, the rod driving the threaded portion of the rod of the injection push rod drives the ring body to rotate and The display window presents the dose value. The metering injector of claim 1, wherein the first The side end of the joint end of the sleeve is formed with a plurality of hooks arranged at intervals, and the outer peripheral surface of the joint end forms a flap portion, and the inner portion of the second sleeve forms a partition between the sleeve portion and the extension tube portion. And having a shaft tube portion passing through the partition portion, the partition portion partitioning the inner space of the second sleeve into an assembly space in the socket portion and an active space in the extension tube portion, the second sleeve The assembly space forms a mounting opening at the outer end of the sleeve portion, and the sleeve portion forms a snap-in flange adjacent to the assembly opening in the movable space, and the outer peripheral wall of the sleeve portion forms a plurality of pressing elastic pieces and is formed around the pressing elastic piece. The slot, the latching flange can hook the hook of the engaging end of the first sleeve, and the pressing elastic piece can be pressed to push the hook away from the engaging flange. The metered syringe of claim 2, wherein the shaft portion of the second sleeve comprises a first section in the assembly space and a second section in the movable space, the second sleeve being on the shaft A ring portion connecting the partition portion is formed on a periphery of the first portion of the pipe portion, the shaft tube portion forming an axially penetrating middle hole, and the inner wall of the ring portion at the periphery of the first portion of the shaft tube portion is formed with at least one end bump The outer peripheral surface of the first section of the shaft tube portion has two diametrically opposed limit stops, and the limit stop has a spacing between the partition portion and the partition portion; the dose indicates that the wheel ring faces the partition portion of the ring body The one end ring row protrudes from the plurality of hook pieces, and the plurality of hook pieces are arranged at equal intervals, the hook pieces are hooked on the limit block, so that the dose display wheel ring can only rotate at a fixed point, and the second set The end bumps of the barrel abut against the gap between the ends of the two adjacent hooks. The metering syringe of claim 3, wherein the inner wall of the extension tube portion of the second sleeve forms two radial corresponding guiding protrusions; the injection push rod comprises a sliding sleeve, and the sliding sleeve has a set And a fixing portion formed at one end of the sleeve, the sleeve system movably extending into the extension tube of the second sleeve The movable space of the portion is sleeved on the outer side of the shaft tube portion, and the fixing portion is connected to the rod connecting portion of the rod body and the operating member to be linked together; the outer peripheral surface of the sleeve is distributed to form two guiding grooves, and the guiding portion Each of the grooves has an axially extending straight groove portion and a spiral groove portion. The straight groove portion has a first groove end and a second groove end respectively located at two axial ends, and the spiral groove portion is respectively located in two phases. Between the adjacent straight groove portions, and the first groove end of the groove portion of the two adjacent straight groove portions is spirally rotated by 180 degrees to engage the second groove end of the other straight groove portion adjacent to the side, the sliding sleeve is sleeved by the sleeve The upper two guiding grooves respectively provide the inner wall of the extending pipe portion of the second sleeve into which two radially corresponding guiding protrusions protrude. The metering syringe according to claim 4, wherein the second section end of the shaft portion of the second sleeve forms two radially corresponding elastic pieces, and the ends of the elastic pieces each form a single inclined surface. The abutting projection has a plurality of oblique grooves on the inner circumferential surface of the sliding sleeve, and the abutting projections at the end of the elastic portion of the second sleeve shaft portion abut against the inclined groove portion. The metering syringe according to claim 5, wherein the sliding sleeve forms an annular baffle having an inner hole and a connecting portion extending from the inner hole edge toward the end of the fixing portion inside one end of the connecting operating member. Forming space is formed between the connecting portion and the inner wall of the fixing portion, and the peripheral wall of the connecting portion is distributed with a plurality of slits extending axially from the end thereof, so that the connecting portion has elasticity of expansion and recovery, and the fixing portion of the sliding sleeve is adjacent to the sliding portion A plurality of snap-fit holes are formed at the annular baffle, and the snap-fit holes communicate with the assembly space; a radially protruding ring flange is formed on the rod connecting portion of the rod body, and a flange is formed at the end of the rod connecting portion, and the rod body extends Inside the sliding sleeve, the rod connecting portion of the rod body is correspondingly inserted into the connecting portion of the sliding sleeve, the ring flange abuts against the side end of the annular baffle, and the flange abuts against the end of the connecting portion to be combined; The operating member comprises a knob portion and a sleeve tube portion formed in the axial direction of the knob portion. The end of the sleeve portion forms a plurality of fixing hooks, and the operating member is sleeved on the outside of the fixing portion of the sliding sleeve The sleeve portion extends into the assembly space of the fastening portion and is sleeved on the outside of the connection portion, and the plurality of fixing hooks are respectively engaged in the fastening holes of the fixing portion of the sliding sleeve. The metering syringe according to any one of claims 2 to 6, wherein the joint end side end of the first sleeve forms a plurality of alignment convex portions, and the alignment convex portions are formed with the hooks Staggered; the sleeve portion of the second sleeve further forms a plurality of alignment recesses corresponding to the alignment protrusions at the mounting opening thereof, and the alignment protrusions and the alignment recesses have an uneven fit.