CN2693260Y

CN2693260Y - Improved safety syringe

Info

Publication number: CN2693260Y
Application number: CN 200420048572
Authority: CN
Inventors: 王希平
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-04-19
Filing date: 2004-04-19
Publication date: 2005-04-20
Anticipated expiration: 2014-04-19

Abstract

The utility model discloses a safety injector, aiming at providing a self-destroying safety injector which has the advantages of simple structure, easy use, lower cost and having needle protection function. The improved safety injector comprises a sliding bush, a needle, a syringe, a piston, a spring, a latching sleeve and a push rod which is arranged in the syringe. An elastic elongation plate is installed in the groove on the rear portion of the sliding bush, which makes dies easier to be manufactured and makes the cost further reduced. One hand can inject and start the safety device, which makes the operation easy. The sliding bush is automatically positioned and in the bidirectional locking to guarantee the needle tip in the protection of the sliding bush in the course of process after the injector is used. The improved safety injector has the reliable function of self-lock. After the injector is used, the push rod is locked in the syringe and can not be pulled out. If the injector is to be used again, the push rod can break and the injector can be further damaged to guarantee the disposability.

Description

A kind of improvement safety injector

Technical field

This utility model relates to a kind of safety injector, particularly relates to a kind of destructing safety syringe with Tip protection function.

Background technology

At present; more and more by the disease that blood, body fluid etc. are propagated; it is the main path of pathophoresis that the syringe needle of the syringe after syringe repeatedly uses and uses is dealt with improperly; and common disposable syringe is using after regular meeting stabs the treatment people of medical personnel or hospital refuse, there is very big potential safety hazard.The applicant once proposed the utility application that name is called " a kind of automatic safety syringe "; it mainly includes sliding sleeve; syringe needle; syringe; piston; spring and place parts such as push rod in the syringe; this utility model has simple in structure; easy to use; not only has the Tip protection function but also have the function of self-destruction; but this utility model people finds in the practical application in later stage; the position that elastic extension plate in this utility model on the sliding sleeve is provided with; for the certain influence that is manufactured with of mould, though thereby mould can make relative some complicated cost that makes to improve.The applicant has carried out setting again in line with the principle that reduces cost to the position of elasticity extension board in this utility model, so proposed this utility model application.

The utility model create contents

The purpose of this utility model provide a kind of simple in structure, easy to use, cost is cheaper, has not only had Tip protection function, but also safety injector that can self-destruction.

For achieving the above object, this utility model is taked following technical scheme: a kind of safety injector, include: sliding sleeve, syringe needle, syringe, piston, spring, lock sleeve and the push rod that places in the syringe, the syringe front end is provided with a conehead that cooperates with described syringe needle and dress pin screw thread, syringe needle is installed on the conehead of described syringe front end by described dress pin screw thread, described push rod front end has the union joint that cooperates with described piston, described sliding sleeve is set in outside the described syringe slidably, it is characterized in that: two grooves are offered at described sliding sleeve rear portion, described two groove places respectively are provided with an elastic extension plate, offer a draw-in groove hole on the described elastic extension plate again; The sliding sleeve middle part offers a short groove at least, and described short groove place is provided with two elasticity clamps; The sliding sleeve front end is a necking down, and the necking down front end has a baffle plate, and described baffle plate center is provided with a hole that syringe needle is stretched out; The front end of described syringe is provided with a perpendicular end surface, and the cylindrical of syringe is provided with the elongated slot that cooperates with described elasticity clamp, and described elongated slot front portion is provided with a limiting plate, but described limiting plate holding is between described two elasticity clamps; Described syringe outer wall respectively is provided with a boss in the corresponding position, draw-in groove hole with the elastic extension plate, and described boss can be fastened on the described elastic extension plate in the draw-in groove hole; Described syringe endoporus rear portion also is provided with the resistance ring that is no less than two; Described push rod is provided with a sliding sleeve unlocking board in the corresponding position with described sliding sleeve elastic extension plate, at least one is the inclined-plane for the opposite face of described sliding sleeve unlocking board and described sliding sleeve elastic extension plate, when the sliding sleeve unlocking board contacted with sliding sleeve elastic extension plate, the effect low sleeve unlocking board on the inclined-plane can make sliding sleeve elastic extension plate open to both sides.Described spring housing is located at outer the putting of the dress pin screw thread of described syringe, and is compressed between the perpendicular end surface of the baffle plate of described sliding sleeve and described syringe.Described lock sleeve is installed in syringe endoporus rear portion and is set on the described push rod; The lock sleeve front portion is the conical surface that inwardly shrinks and has elongated slot more than two, and its cylindrical middle part also is provided with a snap ring; Described push rod body is a crossed stiffened plate, comprises preceding crossed stiffened plate, middle crossed stiffened plate, step flaps and back crossed stiffened plate; The crossed stiffened plate overall dimensions is slightly larger than lock sleeve front end diameter of bore before described, and described middle crossed stiffened plate overall dimensions is less than lock sleeve front end diameter of bore, and described step flaps is at least one, and its external diameter is slightly larger than lock sleeve front end diameter of bore.

In the above-mentioned safety injector, the described triangular in shape and cross section, a cross section that is provided with at syringe endoporus rear portion is trapezoid resistance ring; The cross section of preceding resistance ring is triangular in shape, and its internal diameter is slightly less than the syringe internal diameter, and angle is less between described preceding resistance ring front bevel and axis, and the angle between back bevel and axis is bigger; Back resistance ring cross section is trapezoidal, and angle is all bigger between its forward and backward inclined-plane and syringe axis, and the internal diameter of described back resistance ring is less than preceding resistance ring internal diameter; The front end face vertical axis of the snap ring of described lock sleeve, back bevel and axis angle are bigger, and the external diameter of snap ring equals the syringe diameter of bore, and the width of snap ring is slightly less than the width of forward and backward resistance interannular in the syringe; The front end face of the snap ring of described lock sleeve is slightly larger than the rear end face distance of the front end face of described lock sleeve to described step flaps to the distance of described preceding resistance ring back bevel.

In the above-mentioned safety injector, the diameter of the endoporus of described piston is greater than push rod head union joint diameter, and its length is greater than push rod union joint gauge 1～5mm.

In the above-mentioned safety injector, be equivalent to the lock sleeve front end face apart from the backward step plate on the crossed stiffened plate behind the described push rod and to snap ring rear end face distance one circular anti-slip plate be set, its external diameter is slightly less than lock sleeve rear end diameter of bore; One weak bonding pad is set on the crossed stiffened plate behind the described push rod, connects by two little joint pins of breaking that are centrosymmetric between its horizontal gusset, connect by the arrowband that can break between the vertical gusset.

In the above-mentioned safety injector, be a transition inclined-plane or transition frustum between crossed stiffened plate and the preceding crossed stiffened plate in the described push rod, inclined-plane and axis angle are not less than 30 °

In the above-mentioned safety injector, the end of the two elasticity clamps at the short groove of described sliding sleeve place is outstanding to the endoporus direction, and projecting height is slightly larger than the degree of depth of elongated slot on the syringe; The height of the boss of described syringe is less than the degree of depth in draw-in groove hole, and the width of described boss is less than the width in draw-in groove hole.

This utility model is owing to take above design, and it has the following advantages:

1, in this utility model the elastic extension plate is arranged in the groove at sliding sleeve rear portion, make that mould is more prone to make, cost further reduces, and more similar safety injector, design of part of the present utility model is comparatively succinct, and it is comparatively convenient to make, and assembling easily, thereby have high-performance, a distinguishing feature cheaply.

2, this utility model can carry out injection operation and start safety device by one hand, and is easy to use; Sliding sleeve is location and two-way locking automatically, guarantees that needle point is in the protection of sliding sleeve always in the processing procedure of this syringe after use, thereby the incident of avoiding needle point to hurt sb.'s feelings takes place.

3, the utlity model has reliable auto-lock function, after the use once, push rod promptly is locked in the syringe, and can not extract.Attempt reuses and all can cause the push rod fracture, and syringe is further damaged, and guarantees disposable use.

4, this utility model piston can be assembled at the end, thereby simplified structure not only, conveniently uses operation (injection operation and ordinary syringe are identical), is easy to guarantee that injected dose is accurate, and is convenient to guarantee the safety of drawing blood and operating.The power of injecting during use changes little, does not influence the comfortableness of injection basically, and to start release mechanism (sliding sleeve reach) be after injection finishes, thereby start-up operation has no adverse effects to the patient.

5, this utility model medicinal liquid space structure is simple, and the syringe part that contacts with medicinal liquid only is syringe and piston (identical with ordinary syringe), thereby can reliably avoid medicinal liquid contaminated, guarantees to demonstrate,prove injection safety.

6, the conveniently replaced standard needle of this utility model can satisfy the multiaspect instructions for use.

7, this utility model structure is easy to realize automatic assembling, for mass production has been created good condition.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Fig. 2 is the vertical view of Fig. 1.

Fig. 3 is the structural representation of this utility model when drawing liquid.

Fig. 4 is the structural representation of this utility model when injection finishes.

Structural representation when Fig. 5 is broken for this utility model.

Fig. 6 realizes the structural representation of Tip protection function for this utility model.

The specific embodiment

For structure of the present utility model better is described, conjunction with figs. is described in detail as follows for an embodiment now:

As shown in Figure 1 and Figure 2, be the embodiment that this utility model provides, the structural representation when it does not use after for the assembling of a kind of safety injector.This syringe includes: syringe needle 1, spring 2, sliding sleeve 3, piston 4, syringe 5, push rod 6 and lock sleeve 7.

Entry needle 1 is connected needle stand endoporus 12 and syringe conehead 52 by dress pin screw thread 51 engagements of the flange 11 on its needle stand of rotation with syringe 5 front ends.

The outside that is set in syringe 5 that sliding sleeve 3 slides, two grooves 36 are offered at its rear portion, two grooves, 36 places respectively are provided with an elastic extension plate 31, offer a draw-in groove hole 311 on the elastic extension plate 31 again, the sliding sleeve middle part offers two short grooves 32, and short groove 32 places respectively are provided with two elasticity clamps 321,322, and sliding sleeve 3 front ends are a necking down 33, the necking down front end has a baffle plate 34, and baffle plate 34 centers are provided with a centre bore 35 that syringe needle is stretched out.

The front end of syringe 5 is provided with a perpendicular end surface 53, the cylindrical of syringe 5 is provided with and elasticity clamp 321,322 two elongated slots 54 that cooperate, elongated slot 54 front portions respectively are provided with a limiting plate 55, two elasticity clamps 321,322 end is outstanding to the endoporus direction, projecting height is slightly larger than the degree of depth of elongated slot 54 on the syringe, so two elasticity clamps 321, can slide in elongated slot 54 in 322 end, and but limiting plate 55 holdings are at two elasticity clamps 321, between 322: the internal diameter rear portion of syringe 5 is provided with two resistance ring 56,57, the cross section of preceding resistance ring 56 is triangular in shape, its internal diameter is slightly less than syringe 5 internal diameters, angle is 10 ° between the front bevel of preceding resistance ring 56 and axis, back bevel and axis normal, back resistance 57 ring cross sections are trapezoidal, before it, angle is 45 ° between back bevel and syringe axis, and the internal diameter of back resistance ring 57 is less than the internal diameter of preceding resistance ring 56; Syringe 5 outer walls respectively are provided with a boss 58 in the corresponding position with elastic extension plate 31 draw-in groove holes 311, and the height of boss 58 is less than the degree of depth in draw-in groove hole 311, and the width of boss 58 is less than the width in draw-in groove hole 311, and boss 58 can be fastened in the draw-in groove hole 311; In addition, for the ease of the equipment, between the cylindrical of perpendicular end surface 52 and syringe 5 by a conical surface 59 transition.

Lock sleeve 7 is installed in syringe 5 endoporus rear portions and is set on the push rod 6, its front portion is the conical hollow flexure strip 71 that inwardly shrinks and has three elongated slots, also be provided with a snap ring 72 on the cylindrical in the middle of the lock sleeve 7, the front end face vertical axis of snap ring 72, back bevel and axis angle are 45 °, the external diameter of snap ring 72 equals syringe 5 diameter of bores, and the width of snap ring 72 is slightly less than the width of 56,57 on the interior forward and backward resistance ring of syringe.

The crossed stiffened plate of push rod 6 is made into structure, size is different several sections: preceding crossed stiffened plate 62, middle crossed stiffened plate 63, step flaps 64 and back crossed stiffened plate 65; The overall dimensions of preceding crossed stiffened plate 62 is slightly larger than lock sleeve front end diameter of bore, middle crossed stiffened plate 63 overall dimensions are less than lock sleeve front end diameter of bore, by an inclined-plane 621 (the perhaps conical surface) transition, inclined-plane 621 is 45 ° with the angle of axis between preceding crossed stiffened plate 62 and the middle crossed stiffened plate 63; The number of step flaps 64 is one, and also by an inclined-plane 631 transition, inclined-plane 631 is 15 ° with the angle of axis between itself and the middle crossed stiffened plate 63; Be equivalent to lock sleeve 7 front end faces apart from step flaps 64 on the back crossed stiffened plate 65 and to snap ring 72 rear end face distances one circular anti-slip plate 66 be set, its external diameter is slightly less than lock sleeve 7 rear end diameter of bores; One weak bonding pad 67 is set on the anti-slip plate 66 of back crossed stiffened plate 65, connects by two little joint pins of breaking that are centrosymmetric between its horizontal gusset, connect by the arrowband that can break between the vertical gusset; Back crossed stiffened plate 65 is provided with a taper sliding sleeve unlocking board 68 in the corresponding position with the elastic extension plate 31 of sliding sleeve 3, sliding sleeve unlocking board 68 has at least one to be the inclined-plane with the opposite face of elastic extension plate 31, when sliding sleeve unlocking board 68 contacted with sliding sleeve elastic extension plate 31, the effect low sleeve unlocking board 68 on the inclined-plane can make elastic extension plate 31 open to both sides slightly; In the present embodiment, the end face vertical axis of elastic extension plate 31, and sliding sleeve unlocking board 68 is a conical plate, the end diameter of sliding sleeve unlocking board 68 is less than the internal diameter of sliding sleeve 3, and outside diameter is greater than the internal diameter of sliding sleeve 3.

Certainly; the end face of elastic extension plate 31 is an inclined-plane; and sliding sleeve unlocking board 68 is a cylindrical plate, equally can reach sliding sleeve unlocking board 68 promotion elastic extension plates 31 and make it slightly to the open function in both sides, so above-mentioned two kinds of designs all belong to protection domain of the present utility model.

Spring 2 is set on the overcoat 50 of dress pin screw thread of syringe, and is compressed between the perpendicular end surface 53 of the baffle plate 34 of sliding sleeve and syringe; The periphery that spring 2 is subjected to sliding sleeve necking down 33 endoporus restrictions and syringe front end dress pin thread jacket 50 supports and can lateral deformation not take place and have influence on the elastic force effect.

The diameter of the endoporus of piston 4 is greater than the diameter of the union joint 611 of push rod head 61, and the length of piston 4 endoporus is greater than the thickness 4mm of push rod union joint 611.

In addition, the front end face that also need guarantee the snap ring 72 of lock sleeve 7 is slightly larger than the rear end face distance of the front end face of lock sleeve 7 to step flaps 64 to the distance of preceding resistance ring 56 back bevels.

As shown in Figure 3, in use, move behind the push rod 6, drive piston 4 and move,, thereby realize drawing liquid (or blood drawing) in the syringe 5 anterior vacuum that form.When moving push rod transition inclined-plane 621 to and contact with the lock sleeve front end face, push rod will drive lock sleeve 7 and move behind the front bevel of preceding resistance ring 56, because preceding resistance ring 56 is highly less, the front bevel angle is very little, and 621 oblique angles, transition inclined-plane of push rod are bigger, so lock sleeve 7 will overcome preceding resistance ring 56 dampings and slippage backward, and the snap ring 72 on the lock sleeve 7 slide into syringe before, back resistance ring 56, in the time of between 57, because back resistance ring 57 internal diameters are less, and its front bevel and axis angle are bigger, thereby resistance increases, move after making lock sleeve 7 no longer, because there is good elasticity lock sleeve 7 front portions, its preceding flexure strip 71 is subjected to 621 effects of transition inclined-plane and push rod transition inclined-plane 621 is crossed in distortion and slide to crossed stiffened plate 62 surfaces before the push rod, realizes continuing drawing liquid (or blood drawing) and operates until drawing liquid (or blood drawing) and finish.Back pulling-pushing rod necessary when this syringe utilization is used as can be seen moves, realized the functional localization of lock sleeve 7, because the rear end face and the axis normal of preceding resistance ring 56, and the front end face of the snap ring 72 on the lock sleeve 7 also with axis normal, thereby realized that the lock sleeve 7 of functional localization can not move forward and backward.

As shown in Figure 4, the injection liquid operation is identical with ordinary syringe, be that push rod 6 promotes that pistons 4 move forwards and with medicinal liquid through syringe 5 and syringe needle 1 and in the injection human body in syringe, this moment, the lock sleeve front end face moved after, thereby the step flaps 64 on the push rod 6 will be by anterior flexure strip 71 endoporus of lock sleeve, because the preceding flexure strip 71 of lock sleeve 7 has better elasticity, thereby it is also less relatively to the resistance of push rod 6, unlikely causing injected the power significant change, can not cause that promptly injection is uncomfortable, contact with syringe endoporus antetheca once more when shifting piston 4 front end faces onto, injection finishes.Push rod 6 also was limited in the syringe 5 by lock sleeve 7 and can not pulls out once more this moment, because if this moment is pumpback push rod 6 backward once more, the rear end face of the step flaps 64 on it will contact with the front end face of lock sleeve 7, because both ends of the surface are equal and axis normal, thereby will produce very big resistance, and hole dimensions are close in the anti-slip plate 66 on the push rod 6 and the lock sleeve 7, thereby prevented to contract in the snap ring 72 on the lock sleeve and leave stopping of forward and backward resistance ring 56,57 and deviate from; Further increase pulling force, push rod 6 will take place to rupture and damage at joint pin on the 67 horizontal gussets of weak bonding pad and the thin linking belt place on the vertical gusset, thus reuse (as shown in Figure 5) that has prevented syringe.

As shown in Figure 6; during normal running; inject finish (or behind patient body extraction injection needle); when slightly firmly promoting push rod 6 forward again; because push rod union joint 61 thickness are less than hole length in the piston 4; thereby piston transition cylinder 41 will be compressed; be that push rod 6 can continue about 1～3mm that moves forward; sliding sleeve unlocking board 68 because injection finishes on the rear push-rod 6 has come close to or in contact with the end of sliding sleeve elastic extension plate 31; thereby when push rod 6 continues reach; inclined-plane 681 in the push pedal will contact with the end of elastic extension plate 31 and promote extension board 31 and outwards move; make the also outwards slippage of draw-in groove hole 311 end faces that contacts with syringe boss 58 end faces; when amount of movement during greater than the height of boss 58; under the effect of spring 2; relative slip will take place with 5 of syringes in sliding sleeve 3; stopped by the rear end face of the limiting plate on the syringe 5 55 and stop until the back elasticity clamp 322 on the sliding sleeve; because this sliding distance stretches out sliding sleeve 3 front end face length greater than syringe needle 1; thereby the needle point 11 of syringe needle 1 is inclusive in the sliding sleeve 3; thereby avoided the injury of needle point, realized the safety protection function of syringe needle the people.Preceding elasticity clamp 321 on sliding sleeve this moment has been crossed the limiting plate 55 (because the spacing of two elasticity clamps is greater than thickness of limiting plate) on the syringe and has been dropped on position, the limiting plate 55 front end face left side as can be seen, stoped sliding sleeve to move backward, thereby sliding sleeve 3 is limited to position shown in Figure 6, has realized stable safe kinetic energy.

In addition, as can be seen from Figure, wing plate 37 is mounted in the end of sliding sleeve 3, be that operator's forefinger and middle finger are to be clipped in sliding sleeve wing plate 37 places, thereby in case when sliding sleeve 3 and syringe 5 are relatively moved, be actually syringe 5 company's of sliding backward syringe needles 1 and be pulled into together in the sliding sleeve 3, the advantage of this layout is as the careless release mechanism that started, the result is that syringe needle will be pulled out human body automatically, rather than sliding sleeve reach contact human body, pain or the discomfort brought to the patient.

Claims

1, a kind of safety injector, include: sliding sleeve, syringe needle, syringe, piston, spring, lock sleeve and place push rod in the syringe, the syringe front end is provided with a conehead that cooperates with described syringe needle and dress pin screw thread, syringe needle is installed on the conehead of described syringe front end by described dress pin screw thread, described push rod front end has the union joint that cooperates with described piston, described sliding sleeve is set in outside the described syringe slidably, it is characterized in that:

Two grooves are offered at described sliding sleeve rear portion, and described two groove places respectively are provided with an elastic extension plate, offer a draw-in groove hole on the described elastic extension plate again; The sliding sleeve middle part offers a short groove at least, and described short groove place is provided with two elasticity clamps; The sliding sleeve front end is a necking down, and the necking down front end has a baffle plate, and described baffle plate center is provided with a hole that syringe needle is stretched out;

The front end of described syringe is provided with a perpendicular end surface, and the cylindrical of syringe is provided with the elongated slot that cooperates with described elasticity clamp, and described elongated slot front portion is provided with a limiting plate, but described limiting plate holding is between described two elasticity clamps; Described syringe outer wall respectively is provided with a boss in the corresponding position, draw-in groove hole with the elastic extension plate, and described boss can be fastened on the described elastic extension plate in the draw-in groove hole; Described syringe endoporus rear portion also is provided with the resistance ring that is no less than two;

Described push rod is provided with a sliding sleeve unlocking board in the corresponding position with described sliding sleeve elastic extension plate, at least one is the inclined-plane for the opposite face of described sliding sleeve unlocking board and described sliding sleeve elastic extension plate, when the sliding sleeve unlocking board contacted with sliding sleeve elastic extension plate, the effect low sleeve unlocking board on the inclined-plane can make sliding sleeve elastic extension plate open to both sides.

Described spring housing is located at outer the putting of the dress pin screw thread of described syringe, and is compressed between the perpendicular end surface of the baffle plate of described sliding sleeve and described syringe.

Described lock sleeve is installed in syringe endoporus rear portion and is set on the described push rod; The lock sleeve front portion is the conical surface that inwardly shrinks and has elongated slot more than two, and its cylindrical middle part also is provided with a snap ring;

Described push rod body is a crossed stiffened plate, comprises preceding crossed stiffened plate, middle crossed stiffened plate, step flaps and back crossed stiffened plate; The crossed stiffened plate overall dimensions is slightly larger than lock sleeve front end diameter of bore before described, and described middle crossed stiffened plate overall dimensions is less than lock sleeve front end diameter of bore, and described step flaps is at least one, and its external diameter is slightly larger than lock sleeve front end diameter of bore.

2, safety injector according to claim 1 is characterized in that: the described triangular in shape and cross section, a cross section that is provided with at syringe endoporus rear portion is trapezoid resistance ring; The cross section of preceding resistance ring is triangular in shape, and its internal diameter is slightly less than the syringe internal diameter, and angle is less between described preceding resistance ring front bevel and axis, and the angle between back bevel and axis is bigger; Back resistance ring cross section is trapezoidal, and angle is all bigger between its forward and backward inclined-plane and syringe axis, and the internal diameter of described back resistance ring is less than preceding resistance ring internal diameter; The front end face vertical axis of the snap ring of described lock sleeve, back bevel and axis angle are bigger, and the external diameter of snap ring equals the syringe diameter of bore, and the width of snap ring is slightly less than the width of forward and backward resistance interannular in the syringe; The front end face of the snap ring of described lock sleeve is slightly larger than the rear end face distance of the front end face of described lock sleeve to described step flaps to the distance of described preceding resistance ring back bevel.

3, safety injector according to claim 1 is characterized in that: the diameter of the endoporus of described piston is greater than push rod head union joint diameter, and its length is greater than push rod union joint gauge 1～5mm.

4, safety injector according to claim 2 is characterized in that: the diameter of the endoporus of described piston is greater than push rod head union joint diameter, and its length is greater than push rod union joint gauge 1～5mm.

5, according to claim 1 or 2 or 3 or 4 described safety injectors, it is characterized in that: be equivalent to the lock sleeve front end face apart from the backward step plate on the crossed stiffened plate behind the described push rod and to snap ring rear end face distance one circular anti-slip plate be set, its external diameter is slightly less than lock sleeve rear end diameter of bore; One weak bonding pad is set on the crossed stiffened plate behind the described push rod, connects by two little joint pins of breaking that are centrosymmetric between its horizontal gusset, connect by the arrowband that can break between the vertical gusset.

6, according to claim 1 or 2 or 3 or 4 described safety injectors, it is characterized in that: be a transition inclined-plane or transition frustum between crossed stiffened plate and the preceding crossed stiffened plate in the described push rod, inclined-plane and axis angle are not less than 30 °

7, safety injector according to claim 5 is characterized in that: be a transition inclined-plane or transition frustum between crossed stiffened plate and the preceding crossed stiffened plate in the described push rod, inclined-plane and axis angle are not less than 30 °

8, according to claim 1 or 2 or 3 or 4 or 7 described safety injectors, it is characterized in that: the end of the two elasticity clamps at the short groove of described sliding sleeve place is outstanding to the endoporus direction, and projecting height is slightly larger than the degree of depth of elongated slot on the syringe; The height of the boss of described syringe is less than the degree of depth in draw-in groove hole, and the width of described boss is less than the width in draw-in groove hole.

9, safety injector according to claim 5 is characterized in that: the end of the two elasticity clamps at the short groove of described sliding sleeve place is outstanding to the endoporus direction, and projecting height is slightly larger than the degree of depth of elongated slot on the syringe; The height of the boss of described syringe is less than the degree of depth in draw-in groove hole, and the width of described boss is less than the width in draw-in groove hole.

10, safety injector according to claim 6 is characterized in that: the end of the two elasticity clamps at the short groove of described sliding sleeve place is outstanding to the endoporus direction, and projecting height is slightly larger than the degree of depth of elongated slot on the syringe; The height of the boss of described syringe is less than the degree of depth in draw-in groove hole, and the width of described boss is less than the width in draw-in groove hole.