CN203874223U - Pneumatic needleless injector - Google Patents

Abstract

The utility model discloses a pneumatic needleless injector which comprises a base, an injection component, an air channel component, a manual triggering component, an injected dose adjusting component and a needle cylinder component. An impact piston in the injection component pushes liquid medicine in the needle cylinder component to achieve the injection purpose, high-pressure air is introduced into the air channel component to push the piston in the injection component to move, and the manual triggering component makes contact with a valve element of the air channel component through a trigger and a connecting rod to control opening and closing of the air channel component. A threaded rod and a limit stop block in the injected dose adjusting component are connected through threads, and the threaded rod is rotated to enable the limit stop block to move in the axial direction to limit the stop initial position of the impact piston in the injection component, so that the dose adjusting purpose is achieved. The needle cylinder component is sealed through a plunger and a one-way valve structure of a nozzle, and is used for guiding liquid medicine in and storing liquid medicine.

Description

A kind of pneumatic needleless injector

Technical field

This utility model belongs to medical instruments field, specifically, relates to a kind of needleless injector.

Background technology

Traditional syringe is draw point to be penetrated to human body skin inject, and does easily skin is caused to damage like this, produces pain clearly, and the danger of broken needle even also likely occurs.And, if syringe needle is clean not, also can cause transmission of disease.Compare with traditional injection, Needleless injection has a lot of advantages: it is very little to the stimulation of teleneuron, without obvious pain; Owing to there is no syringe needle, eliminated the pathophoresis causing because syringe needle is unholiness; After injection, drug diffusion is even, is beneficial to absorption.In addition, because needleless injector can be used continuously, compare with traditional syringe, reduced the processing of medical waste, purified environment, also reduced the expense of garbage disposal.According to the survey: the frightened syringe of adult that has 20% minor and 8.1% in developed country.For suffering from the often patient of injection of the needs such as diabetes, Needleless injection is good a selection beyond doubt.

Utility model content

technical problem:this utility model provide a kind of without manual loading, can realize the pneumatic needleless injector that injected dose regulates.

technical scheme:pneumatic needleless injector of the present utility model, comprise pedestal, for propelling the injecting assembly of medicinal liquid, for introducing the gas circuit assembly of Compressed Gas, for controlling manual triggers assembly that gas circuit assembly opens and closes, for regulating the injected dose adjusting part of liquid dose, for importing and the syringe assembly of receiving medical liquids, the gas push injecting assembly action that gas circuit assembly is introduced, propels the medicinal liquid in syringe assembly;

Injecting assembly comprise be arranged on pedestal top sleeve, be arranged on sleeve stage casing and can be along the reciprocating impact piston in sleeve axle center, be arranged on rise pore and backhaul pore on sleeve lining, rise pore is positioned at the extreme position of impact piston forward stroke, and backhaul pore is positioned at the extreme position that impact piston is return stroke;

Gas circuit assembly comprises the first gas passage, the second gas passage and the 3rd gas passage being arranged in pedestal, is arranged on the Direct Action Type spool in the first gas passage, and is arranged on the first exhaust passage and the second exhaust passage on the first gas passage inwall; The first exhaust passage and the second exhaust passage are communicated with the first gas passage with pedestal outside atmosphere; Second gas passage one end is connected with the end face seal end of Direct Action Type spool, and the other end is communicated with backhaul pore, and the 3rd gas passage one end is connected with the circumferential seal end of Direct Action Type spool, and the other end is communicated with rise pore; The first exhaust passage and the second exhaust passage are communicated with the first gas passage respectively with ambient atmosphere;

Manual triggers assembly comprises the hinged connecting rod in the trigger, one end and the trigger end that are hinged on pedestal, the anterior spool hinged with the connecting rod other end, anterior spool is arranged in the first gas passage, and the other end of anterior spool is relative with the end face seal end of Direct Action Type spool;

Dosage adjusting part be arranged on sleeve one end inner side and with impact piston one end in contact, comprise positioning seat, be enclosed within movable limited block and the threaded rod of positioning seat inside, movable limited block can move back and forth but can not rotate along positioning seat axis, threaded rod one end is connected with positioning seat inner thread, and the other end and movable limited block are threaded connection;

Syringe assembly is arranged on the sleeve other end, comprise syringe, be arranged on syringe one end injection nozzle, be arranged on syringe, connect injection nozzle one end side in order to connect medicinal liquid storage device syringe connector, be arranged on plunger in syringe, be arranged on syringe positioning seat and the clamp nut of syringe other end lateral surface, syringe connects as one by clamp nut and syringe positioning seat, syringe positioning seat is fixedly connected with sleeve one end, plunger one end is connected with impact piston, in syringe connector, is provided with one-way valve structures.

In a kind of preferred version of the pneumatic needleless injector of this utility model, threaded rod is connected by trapezoidal thread with movable limited block.

In a kind of preferred version of the pneumatic needleless injector of this utility model, in injection nozzle, be provided with one-way valve structures, on the cooperation face of cylinder of the spool of one-way valve structures, be provided with arc groove.

In a kind of preferred version of the pneumatic needleless injector of this utility model, syringe is to be connected to form by front syringe and rear syringe two parts.

In a kind of preferred version of the pneumatic needleless injector of this utility model, between plunger and impact piston, be provided with connector, plunger embeds from connector one end and can move back and forth along connector axis, and impact piston is fixedly connected with the connector other end.

beneficial effect:this utility model compared with prior art, has the following advantages:

1. manual triggers assembly has been saved the required power of cocking on the one hand, on the other hand, existing syringe trigger architecture is by trigger, to push the bulb shape shaft part of spool leading portion, thereby spool is advanced, and this utility model has added connecting rod to be connected with spool, by connecting rod, remove to promote spool and advance, reduced the risk that spool is bent, also reduce the requirement on machining accuracy of spool, improved the service life of spool;

2. dosage regulates and has adopted the multistage screw thread kind of drive, and existing dosage governor motion mainly adopts the transmission of single-stage screw thread.Compare with existing mechanism, by the transmission effect of the multistage screw thread kind of drive, can make the stroke of positive stop be amplified on the one hand, particularly, under the requirement that dosage regulates, can shorten the shift motion of outside dosage adjusting knob on a large scale, simplified overall dimensions; Can proportioning go out different minimal adjustment scale division values on the other hand, and the dose value that makes to regulate can be and increases linearly or reduce.

3. the design of syringe has adopted separate front and back formula structure, can will after injection, need the part partial disassembly of disinfection, compared with prior art, without the dismounting disinfection of carrying out complete machine, simplified the program of disinfecting, also allowed user operate and be more prone to.

4. on the cooperation of the spool in the one-way valve structures in the injection nozzle face of cylinder, be provided with arc groove, arc groove arranges along valve core axis's direction, play the effect that is communicated with spool both sides, this structural design can shorten whole valve core length effectively, thereby reduced after having injected, residues in the amount of liquid medicine in valve opening.General conventional inner elements of check valve as shown in Figure 8 c, is that whole valve core length is divided into two sections, and one section for spool is supported in to hole, holes, using hole as the passage of medicinal liquid circulation on the face of cylinder of another section.And the principle of the inner elements of check valve that the design adopts is: two shaft part functions of conventional spool are synthesized to one, by slotting on the cooperation face of cylinder, the groove forming, as the passage of medicinal liquid circulation, provides a kind of feasible prioritization scheme for reducing the liquor residue of needleless injector.

Accompanying drawing explanation

Fig. 1 is outward appearance front view of the present utility model.

Fig. 2 a is the cutaway view under state to be triggered.

Fig. 2 b is that the axle of connector is surveyed view.

Fig. 2 c is the partial enlarged view of plunger, connector and impact piston annexation.

Fig. 3 a surveys view for triggering the axle of trigger in assembly.

Fig. 3 b surveys view for triggering the axle of assembly middle front part spool.

Fig. 4 is the cutaway view in trigger process.

Fig. 5 is trigger process cutaway view while completing.

Fig. 6 a is the topology view of injected dose adjusting part.

Fig. 6 b is the partial enlarged view of analysing and observe part shown in Fig. 6 a.

Fig. 7 a is the structure cutaway view of syringe components.

Fig. 7 b is the explosive view after syringe assembly partial disassembly.

Fig. 8 a is the cutaway view at injection nozzle injection port place.

Fig. 8 b is that the axle of injection nozzle spool is surveyed view.

Fig. 8 c is that the axle of existing conventional spool is surveyed view.

In figure, have: sleeve 11, impact piston 12, shaft part 121, rise pore 13, backhaul pore 14, trigger 21, rotating shaft 211, square hole 212, trigger pin-and-hole 213, connecting rod 22, anterior spool 23, end face O RunddichtringO 231, front valve core is O RunddichtringO 232 radially, anterior spool groove 233, spool pin-and-hole 234, positioning seat 31, positioning seat screwed hole 311, positioning seat step surface 312, positioning seat hold-down screw 313, positioning seat endoporus 314, location end face 315, movable limited block 32, limiting stand terrace 321, tapped blind hole 322, keyway 323, alignment pin 324, threaded rod 33, adjusting knob 331, regular screw threads section 332, trapezoidal thread section 333, adjusting knob screwed hole 334, screw thread end face 335, syringe 41, front syringe 411, rear syringe 412, cavity 413, the spacing end face 414 of plunger, syringe positioning seat end face 415, thread separation shaft part 416, valve opening 417, injection nozzle 42, spool 421, the face of cylinder 422, arc groove 423, nozzle bore 424, disposable nozzle 425, micropore 426, nozzle nut 427, nozzle face O RunddichtringO 428, mouth of pipe O RunddichtringO 429, syringe connector 43, threaded shaft section 431, one-way valve spring 432, inner elements of check valve 433, inner elements of check valve O RunddichtringO 434, block 435, plunger 44, plunger step surface 441, plug 442, stopper head 443, clamp nut 45, syringe positioning seat 46, positioning seat threaded shaft section 461, syringe positioning seat step surface 462, holding screw 463, syringe locating hole 464, connector 47, First terrace 471, semicircle macropore 472, the first semicircle aperture 473, the second semicircle aperture 474, lash space 475, the first gas passage 51, front aperture 511, the second gas passage 52, the 3rd gas passage 53, Direct Action Type spool 54, direct-acting valve core passage 541, inclined-plane 542, air inlet O RunddichtringO 543, aerofluxus O RunddichtringO 544, the first exhaust passage 55, the second exhaust passage 56, returning spring 57, pedestal 6, air inlet 61, medicine storage device 7, conventional spool 8, spool coordinates section 81, fluid passage shaft part 82, medicinal liquid opening 83.

The specific embodiment

Below in conjunction with drawings and Examples, the technical solution of the utility model is described in detail.

Fig. 1 is the outward appearance close-up view of syringe, external form is tommy gun, comprises trigger 21, connecting rod 22, the first exhaust passage 55, the second exhaust passage 56, pedestal 6, adjusting knob 331, sleeve 11, rotating shaft 211, syringe positioning seat 46, clamp nut 45, syringe 41, syringe connector 43, nozzle nut 427, disposable nozzle 425, medicine storage device 7.Trigger 21 is by rotating shaft 211 and the hinged formation rotation relation of pedestal 6, and trigger 21 is by straight pin and the hinged formation rotation relation of connecting rod 22.

Fig. 2 a is the section of structure under syringe state to be triggered.Air inlet 61 is positioned at the rearward end of pedestal 6, on air inlet 61 inwalls, has screw thread, during use, general gas-tpe fitting is connected on the screw thread of air inlet 61, and the other end of gas-tpe fitting connects steam hose, and gases at high pressure are incorporated in air inlet 61.The gases at high pressure that enter from air inlet 61 flow by direct-acting valve core passage 541 directions to anterior spool 23 in the middle of Direct Action Type spool 54, on the right-hand member boss of anterior spool 23, cover has end face O RunddichtringO 231, when cocking 21 promotes anterior spool 23, end face O RunddichtringO 231 can be pressed on the inclined-plane 542 of Direct Action Type spool 54, and blocking-up is flow through from direct-acting valve core passage 541 gas coming and entered the second gas passage 52.Shown in Fig. 2 a is not under excited state, and now not and 231 laminatings of end face O RunddichtringO, so gases at high pressure can not enter in the second gas passage 52 on inclined-plane 542.Meanwhile, are now arranged in front valve core on anterior spool 23 front aperture 511 that radially O RunddichtringO 232 is pressed into the first gas passage 51 and formed sealing, thereby blocking-up gases at high pressure are from shown in first exhaust passage 55(Fig. 1) discharge.The first exhaust passage 55 is positioned on the wall shown in Fig. 1, with front aperture 511 be positioned at front valve core radially the part of O RunddichtringO 232 left ends be communicated with.So the gases at high pressure in the second gas passage 52 have finally entered by backhaul pore 14 cavity that is positioned at sleeve 11, impact piston 12 directions of advance.Meanwhile, the air inlet O RunddichtringO 543 on Direct Action Type spool 54 has been pressed in the first gas passage 51, has stoped gases at high pressure to be promoted impact pistons 12 and advanced by flow through rise pore 13 of the 3rd gas passage 53.Therefore, impact piston 12 is fitted with movable limited block 32 under the effect of gases at high pressure.As shown in Fig. 2 a to Fig. 2 c, the shaft part 121 of impact piston 12 front ends has snapped in the second semicircle aperture 474 of connector 47, has been linked to be one with connector 47.As shown in Figure 2 b, along having semicircle macropore 472 and the first semicircle aperture 473 on connector 47 axis directions, semicircle macropore 472 is for holding the stopper head 443 of plunger 44 for the profile of connector 47, thereby plunger 44 can be slided along connector 47 axis.There is First terrace 471 end of connector 47, and as shown in Figure 2 c, First terrace 471 is pressed on the step surface of plunger 44, so under the interconnect function of connector 47, impact piston 12 retracts initial position together by plunger 44.Due to returning of plunger 44, shown in medicine storage device 7(Fig. 1) in medicinal liquid under atmospheric effect, be pressed in the cavity 413 of syringe 41.When impact piston 12 is pushed ahead, the end face 122 of impact piston 12 clashes into the end face of stopper head 443, promotes plunger 44 and travels forward, thereby the medicinal liquid in cavity 413 is propelled out to syringe exterior; By changing the length of stopper head 443, can adjust the length of the lash space 475 between plunger 44 and impact piston 12, be conducive to improve the power of injection.

Cocking 21 can promote anterior spool 23 by connecting rod 22 and advance.Fig. 3 a is that the axle of trigger 21 is surveyed view.On trigger 21, have square hole 212, connecting rod 22 can be inserted in square hole, and by trigger pin-and-hole 213, insert pin and carry out hinged.The axle of anterior spool 23 is surveyed view as shown in Figure 3 b, has anterior spool groove 233 on anterior spool 23, and the other end of connecting rod 22 inserts in anterior spool groove 233 and by spool pin-and-hole 234, inserts pin and carry out hinged.Therefore, when cocking 21, trigger can promote connecting rod 22 and advance, and connecting rod 22 promotes anterior spool 23 and advances.

When cocking 21 moves to the position shown in Fig. 4, end face O RunddichtringO 231 is with shown in inclined-plane 542(Fig. 2 a) fitting has formed sealing, and blocking-up is flow through from direct-acting valve core passage 541 gases at high pressure that come and is entered the second gas passage 52.Simultaneously, front valve core radially O RunddichtringO 232 has now departed from the front aperture 511 of the first gas passage 51, be used for compressing impact piston 12 before and be close to movable limited block 32(as Fig. 2 gases at high pressure a) second gas passage 52 of now can flowing through, shown in first exhaust passage 55(Fig. 1) discharge.Because the air inlet O RunddichtringO 543 on Direct Action Type spool 54 is also pressed in the first gas passage 51, so gases at high pressure can't travel forward by the 3rd gas passage 53 promotion impact pistons 12.

Continue cocking 21 until near forming motion cut-off on pedestal 6, now as shown in Figure 5, air inlet O RunddichtringO 543 is thrown off from the first gas passage 51, gases at high pressure have entered in the 3rd gas passage 53.The second exhaust passage 56 is positioned on the wall shown in Fig. 1, is communicated with the cavity between air inlet O RunddichtringO 543 and aerofluxus O RunddichtringO 544.In the position shown in Fig. 5, Direct Action Type spool 54 is pushed and moves right, now aerofluxus O RunddichtringO 544 has been blocked being communicated with of cavity between the second exhaust passage 56 and air inlet O RunddichtringO 543 and aerofluxus O RunddichtringO 544, gases at high pressure cannot be from shown in second exhaust passage 56(Fig. 1) discharge, thereby promote impact piston 12, excite forward.The end face 122 of impact piston 12 clashes into the end face of plunger 44, and promotion plunger 44 travels forward until spacing end face 414 laminatings of the plunger step surface 441 of plunger 44 and the plunger of syringe 41.Under the promotion of plunger 44, shown in cavity 413(Fig. 2 a) in medicinal liquid all propelled out.After injection completes, unclamp trigger 21, under the effect of returning spring 57, anterior spool 23 is return together with Direct Action Type spool 54, in the process of returning, pass through shown in second exhaust passage 56(Fig. 1) by gases at high pressure exhaustjet device, finally return to the state shown in Fig. 2 a, completed an injection cycle.

Dosage governor motion assembly as shown in Figure 6 a, comprises adjusting knob 331, threaded rod 33, positioning seat 31, movable limited block 32.Fig. 6 b is the partial enlarged view of Fig. 6 a, threaded rod 33 has respectively regular screw threads section 332 and trapezoidal thread section 333, the diameter of regular screw threads section 332 is less than the diameter of trapezoidal thread section 333, and by the screw thread end face 335 of trapezoidal thread section 333, limits the extreme position of threaded rod 33 right-hand members.Regular screw threads section 332 end faces have adjusting knob screwed hole 334, screw is screwed in adjusting knob screwed hole 334, adjusting knob 331 and threaded rod 33 are connected as a single entity, rotation adjusting knob 331 can drive threaded rod 33 rotations to advance, when adjusting knob 331 contacts with the location end face 315 of positioning seat 31, arrived the extreme position of threaded rod 33 left ends.The regular screw threads section 332 of threaded rod 33 screws with the positioning seat screwed hole 311 on positioning seat 31, and rotation adjusting knob 331 can make threaded rod 33 move along the axis of positioning seat 31.The rear portion that positioning seat 31 inserts sleeve 11, spacing in sleeve 11 by a positioning seat step surface 312, and adopt positioning seat hold-down screw 313 and sleeve 11 to be connected as a single entity.Positioning seat 31 has positioning seat endoporus 314, and movable limited block 32 can be free to slide vertically in positioning seat endoporus 314, and by the extreme sport position of limiting stand terrace 321 restraint limited block 32 right-hand members.Movable limited block 32 has trapezoidal thread blind hole 322, screws with the trapezoidal thread section 333 on threaded rod 33.On movable limited block 32 external cylindrical surfaces, have keyway 323, alignment pin 324 inserts in keyway 323 by the hole on positioning seat 31.By alignment pin 324, snap in the rotation that keyway 323 can restraint limited block 32, and alignment pin 324 can be free to slide along keyway 323.When rotation adjusting knob 331, by the Motion Transmission of regular screw threads section 332 on threaded rod 33 and trapezoidal thread section 333, movable limited block 32 can stretch out from the positioning seat endoporus 314 of positioning seat 31, according to movable limited block 32, stretch out the difference of positioning seat endoporus 314 positions, after can making impact piston 12 per injections complete, be limited to different positions, change the amount of liquid medicine of inhaling, reach the object that regulates dosage.And by the two-stage Motion Transmission of regular screw threads section 332 and trapezoidal thread section 333, the movement travel of movable limited block 32 is by larger than the movement travel of adjusting knob 331; In addition, by the transmission of two-stage screw thread, during the dosage of adjusting, can obtain different minimum division values, thereby improve regulator accuracy of measurement, and can guarantee that the dose value of adjusting is always linearity increase or reduces when rotation adjusting knob 331 is fixedly during the number of turns.

As shown in Figure 7a, syringe positioning seat 46 screws in the screwed hole of sleeve 11 front ends by positioning seat threaded shaft section 461, the extreme position screwing in by 462 restrictions of syringe positioning seat step surface, and compress by holding screw 463, prevent that positioning seat threaded shaft section 461 is loosening.Syringe 41 inserts in the syringe locating hole 464 of syringe positioning seat 46, spacing with the end contact of syringe positioning seat 46 by syringe positioning seat end face 415, and the clamp nut 45 of screwing on is fixing by syringe 41.

As shown in Figure 7b, syringe 41 has adopted separate type, removable front syringe 411 and the rear syringe 412 of being divided into, and rear syringe 412 ends form dismountable annexation by thread separation shaft part 416 and front syringe 411.When front syringe 411 with after syringe 412 separated after, plunger 44 and plug 442 have exposed syringe exterior, the in the situation that of integral demounting syringe not, can complete the cleaning and sterilizing work of plunger 44, plug 442, front syringe 411 etc. and medicinal liquid contact portion.

Front end at front syringe 411 is provided with injection nozzle 42 and syringe connector 43, is both provided with individual event valve structure.Fig. 8 a is injection nozzle 42 and 43 structural representations of syringe connector, syringe connector 43 (is connected with injection nozzle 42 with front syringe 411 one end by threaded shaft section 431, the one end not being connected with rear syringe 412) side connects, one-way valve spring 432 in compressive state when inject state not, inner elements of check valve O RunddichtringO 434 on inner elements of check valve 433 is pressed in and on the inclined-plane of syringe connector 43 inside, realizes sealing, the other end of one-way valve spring 432 is pressed on block 435, there is screw thread block 435 outsides, rotary block 435 can make it along syringe connector 43, move, thereby change the decrement of one-way valve spring 432, major function is minimum pressure required while changing inner elements of check valve 433 forwards unlatching.Injection nozzle 42 mouth of pipe one end covers have spring, the other end of spring to be pressed on spool 421 end faces.Injection nozzle 42 is pressed on front syringe 411 inside by nozzle nut 427, and by 428 sealings of nozzle face O RunddichtringO.The structure of spool 421 as shown in Figure 8 b.In Fig. 8 b, the face of cylinder 422 of spool 421 is with shown in valve opening 417(Fig. 8 a of front syringe 411) fit and slide, coordinate on the face of cylinder 422 and have arc groove 423, the medicinal liquid being promoted by plug 442 can flow through from groove.Fig. 8 c is the structure chart of existing conventional spool 8, at whole valve core length, spool be can be divided into and section 81 and fluid passage shaft part 82 coordinated, spool coordinates section 81 for spool is supported in to valve opening, has medicinal liquid opening 83 on the wall of medicine liquid channel shaft part 82, can make medicinal liquid flow through from hole.Therefore compare existing valve core structure shown in Fig. 8 c, on the cooperation face of cylinder 422 of spool 421, arrange after arc groove 423, just without additional liquid passage shaft part on spool, thereby shortened the length of whole spool, be conducive to reduce after having injected remaining in the amount of liquid medicine in valve opening 417.The similar of inner elements of check valve 433 and spool 421.When plunger 44 is pushed to the position shown in Fig. 8 a, the inner elements of check valve O RunddichtringO 434 on inner elements of check valve 433 will firmly be pressed on inclined-plane and realize and sealing under the extruding of medicinal liquid, so medicinal liquid can not reflux into shown in medicine storage device 7(Fig. 1) in.Simultaneously, under the promotion of medicinal liquid pressure, mouth of pipe O RunddichtringO 429 on spool 421 will pushed away from sealing inclined-plane, and medicinal liquid enters by the arc groove on spool 421 in the nozzle bore 424 of injection nozzle 42, under the contraction extruding of the micropore 426 of disposable nozzle 425 ends, finally be ejected into the external world.Disposable nozzle 425 is connected as a single entity by screw thread and injection nozzle 42, after injection completes, disposable nozzle 425 can be unloaded and makes a one-time use only processing.When plunger 44 is return, spool 421 is no longer subject to the extruding of medicinal liquid, under the effect of spring, mouth of pipe O RunddichtringO 429 is pressed in again on inclined-plane and realizes and sealing, now the cavity 413(of front syringe 411 a) can form certain vacuum as Fig. 2, under atmospheric effect, shown in medicine storage device 7(Fig. 1) in medicinal liquid can be pressed in syringe connector 43, and then flow in the cavity 413 of front syringe 411 and realize loading again of medicinal liquid.

Above embodiment is only further illustrating this utility model scheme; after having read this utility model embodiment, those of ordinary skills are to the modification of various equivalents of the present utility model and replace the scope all belong to the protection that this utility model application claim limits.

Claims (5)

1. a pneumatic needleless injector, it is characterized in that, this syringe comprises pedestal, for propelling the injecting assembly of medicinal liquid, for introducing the gas circuit assembly of Compressed Gas, for controlling manual triggers assembly that described gas circuit assembly opens and closes, for regulating the injected dose adjusting part of liquid dose, for importing and the syringe assembly of receiving medical liquids, the gas push injecting assembly action that described gas circuit assembly is introduced, propels the medicinal liquid in syringe assembly;

Described injecting assembly comprise be arranged on pedestal top sleeve (11), be arranged on described sleeve (11) stage casing and can be along the reciprocating impact piston in sleeve (11) axle center (12), be arranged on rise pore (13) and backhaul pore (14) on sleeve (11) inwall, described rise pore (13) is positioned at the extreme position of impact piston (12) forward stroke, and described backhaul pore (14) is positioned at the extreme position that impact piston (12) is return stroke;

Described gas circuit assembly comprises the first gas passage (51) being arranged in pedestal, the second gas passage (52) and the 3rd gas passage (53), be arranged on the Direct Action Type spool (54) in described the first gas passage (51), and be arranged on the first exhaust passage (55) and the second exhaust passage (56) on the first gas passage (51) inwall, described the second gas passage (52) one end is connected with the end face seal end of Direct Action Type spool (54), the other end is communicated with backhaul pore (14), described the 3rd gas passage (53) one end is connected with the circumferential seal end of Direct Action Type spool (54), the other end is communicated with rise pore (13), described the first exhaust passage (55) and the second exhaust passage (56) are communicated with the first gas passage (51) respectively with ambient atmosphere,

Described manual triggers assembly comprises the hinged connecting rod (22) in the trigger (21), one end and described trigger (21) end that are hinged on pedestal, the anterior spool (23) hinged with described connecting rod (22) other end, described anterior spool (23) is arranged in the first gas passage (51), and the other end of anterior spool (23) is relative with the end face seal end of Direct Action Type spool (54);

Described dosage adjusting part be arranged on sleeve (11) one end inner side and with impact piston (12) one end in contact, comprise positioning seat (31), be enclosed within positioning seat (31) inner movable limited block (32) and threaded rod (33), described movable limited block (32) can move back and forth but can not rotate along positioning seat (31) axis, threaded rod (33) one end is connected with positioning seat (31) inner thread, and the other end and movable limited block (32) are threaded connection;

Described syringe assembly is arranged on sleeve (11) other end, comprise syringe (41), be arranged on the injection nozzle (42) of described syringe (41) one end, be arranged on the upper side that connects injection nozzle (42) one end of syringe (41) in order to connect the syringe connector (43) of medicinal liquid storage device, be arranged on the plunger (44) in syringe (41), be arranged on syringe positioning seat (46) and the clamp nut (45) of syringe (41) other end lateral surface, syringe (41) connects as one by clamp nut (45) and syringe positioning seat (46), syringe positioning seat (46) is fixedly connected with sleeve (11) one end, plunger (44) one end is connected with impact piston (12), in described syringe connector (43), be provided with one-way valve structures.

2. a kind of pneumatic needleless injector according to claim 1, is characterized in that, described threaded rod (33) is connected by trapezoidal thread with movable limited block (32).

3. a kind of pneumatic needleless injector according to claim 1, is characterized in that, described injection nozzle is provided with one-way valve structures in (42), on the cooperation face of cylinder of the spool of described one-way valve structures (421), is provided with arc groove.

4. according to a kind of pneumatic needleless injector described in claim 1,2 or 3, it is characterized in that, described syringe (41) is to be connected to form by front syringe (411) and rear syringe (412) two parts.

5. according to a kind of pneumatic needleless injector described in claim 1,2 or 3, it is characterized in that, between described plunger (44) and impact piston (12), be provided with connector (47), plunger (44) embeds from connector (47) one end and can move back and forth along connector (47) axis, and impact piston (12) is fixedly connected with connector (47) other end.