CN102688545A

CN102688545A - Structure for disposable syringe and disposable syringe

Info

Publication number: CN102688545A
Application number: CN2012100926966A
Authority: CN
Inventors: 江波
Original assignee: CHANGZHOU HEKANG MEDICAL EQUIPMENT CO LTD
Current assignee: CHANGZHOU HEKANG MEDICAL EQUIPMENT CO LTD
Priority date: 2011-03-18
Filing date: 2012-03-19
Publication date: 2012-09-26
Also published as: CN102688544A; CN202637628U; WO2012126342A1; WO2012126341A1; CN202844270U

Abstract

The invention disclosed a structure for a disposable syringe, comprising a deflecting portion, a blocking portion and a connecting portion which connects the deflecting portion and the blocking portion. The deflecting portion can carry out deflection toward or away from the blocking portion. When the deflecting portion carries out deflection toward the blocking portion, the deflecting portion abuts on the blocking portion. The invention further provides a disposable syringe which adopts the structure.

Description

The structure and the disposable syringe that are used for disposable syringe

Technical field

The present invention relates to be used for a kind of structure of disposable syringe and the disposable syringe of having used this structure.

Background technology

For avoiding to the input of the mankind or animal or cross infection takes place when taking out medium, hypodermic syringe must disposable use, after use promptly as garbage disposal.Use at present maximum disposable syringes by cavity cylindrical shell, syringe needle and be assemblied in that tube is intravital to be decided the journey piston and form.The existing greatest problem of this syringe is after injection finishes; Its syringe needle is still stayed the outside, be not merely syringe rubbish carrying, destroy and make troubles, possibly stab medical personnel because of careless simultaneously; Cause the secondary cross infection of pathogenic bacteria; Become the medical hidden danger that to ignore, still have the probability of being used by secondary in addition, a kind of disposable syringe that after use, can syringe needle be retracted syringe therefore occurred; This disposable syringe also can further be set to the syringe needle that retracts through being arranged on latching structure kayser on core bar and the syringe in syringe, thereby this disposable syringe was lost efficacy.In addition, easy breakpoint can also be set on core bar, thereby can after core bar is pulled back down to the position, core bar be fractureed, guarantee that this disposable syringe can't be used again.

Above-mentioned this disposable syringe retracts syringe and with the purpose of core bar kayser in syringe in order to realize with syringe needle; Generally one or more parts with specific structure need be set on core bar; This structure needs to pass through one or more critical points in one direction; The internal diameter at critical point is slightly smaller than the maximum outside diameter of this structure; Then can not pass through this critical point in the opposite direction, remove on-mechanical means and apply enough big external force on this structure, as when using mechanical assembly machine that this disposable syringe is assembled.

For example; At application number is in China's invention application " safety injector and self-desttruction equipment thereof " of 201110066021.X, on the bar head of core bar, is provided with taper platform structure 11 as shown in Figure 1, and on the endoporus side of needle stand, correspondingly is provided with shoulder (critical point) 12; The internal diameter of shoulder 12 is slightly smaller than the diameter of taper platform structure 11 bottom surfaces; Taper platform structure 11 can push through shoulder by its conical surface when pushing away on the bar head, and when pulling back, the bottom surface of taper platform structure 11 then engages with shoulder 12; Needle stand is applied downward pulling force, thereby needle stand is pulled back to syringe.The defective of this structure is when injection; The process that taper platform structure 11 pushes through shoulder 12 need overcome bigger resistance; Not only put to no little inconvenience to the operator, and unstable like the bad injection process that very easily makes of control, even caused unnecessary pain by the injector.

Publication number is that the PCT patent application of WO2011/029264 discloses " needle point can bounce back disposible safety syringe "; As shown in Figure 2; The compartment of terrain is provided with a pair of

snap flange

21,22 that is respectively taper and inverted cone in opposite directions on core bar, and is provided with the engaging shoulder 23 with square edge that is complementary with it in the syringe inboard.When pulling back core bar, the engaging shoulder 23 be stuck in snap flange 21, between 22, thereby core bar and syringe are fastened togather.The defective of said structure is; When assembling; Even if by the strength of mechanical assembly machine, the snap flange 22 of inverted cone also can't only push away and can damage snap flange 22 directly through the engaging shoulder firmly; And assembling circle 24 that is must employing as shown in Figure 3 funneling or that have a tapering is assisted assembling, has increased one procedure like this and has also increased cost.In addition, the diameter of syringe front end need strengthen giving assembling circle slot milling, and the handle front end of dilated diameter also can cause the incompatibility of the user of being accustomed to using ordinary syringe.

Therefore; Those skilled in the art is devoted to develop a kind of specific structure, and this structure promptly can be used for the pulling back of syringe needle of disposable syringe, can be used for the kayser between core bar and the syringe again; And can overcome above-mentioned defective, and the disposable syringe of having used this structure.

Summary of the invention

Because the above-mentioned defective of prior art; Technical problem to be solved by this invention provides a kind of structure and the disposable syringe of having used this structure that is used for disposable syringe; Make that the kayser of pulling back with core bar of syringe needle is more light and handy, and be that the assembling of this disposable syringe is more easy.

For realizing above-mentioned purpose; The present invention provides a kind of structure that is used for disposable syringe in first aspect; This structure comprises deflector, stop part, and the connecting portion that connects deflector and stop part, deflector can towards or deviate from stop part and carry out deflection; When deflector during towards stop part deflection, deflector is resisted against on the stop part.

In the preferred embodiments of first aspect of the present invention, when deflector was resisted against on the stop part, deflector formed the inclined-plane or the conical surface

In another preferred embodiments of first aspect of the present invention, deflector is full slice system or split blade type.

In another preferred embodiments of first aspect of the present invention, deflector is circle, polygon, petal or bar shaped.

In another preferred embodiments of first aspect of the present invention, this structure is the integral molded plastic molding.

In another preferred embodiments of first aspect of the present invention, deflector has thin root, thick edge.

In another preferred embodiments of first aspect of the present invention, this structure is arranged on the core bar of disposable syringe.

In another preferred embodiments of first aspect of the present invention, this structure is arranged on the syringe inboard of disposable syringe.

In another preferred embodiments of first aspect of the present invention, this structure is arranged on the inboard of central through hole of needle stand of disposable syringe.

The present invention provides a kind of disposable syringe in second aspect; Comprise syringe and core bar, wherein comprise the structure that at least one the present invention provides in first aspect on the core bar, the syringe inboard comprises at least one shoulder; When this structure was set to pull back core bar, structure can not be passed through shoulder downwards.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, on core bar, comprise two structures, be first structure in last structure, the structure of infra is second structure, and first structure and second structure are towards on the contrary; The syringe inboard is provided with shoulder and following shoulder; Shoulder on second structure is set to pass through downwards when after injection finishes, pulling back core bar is passed through shoulder down but can not make progress again, and first structure then is set to can not be downwards through last shoulder.

Further, disposable syringe is being carried out machine when assembling, second structure is set to make the syringe strain and upwards pushes through shoulder and following shoulder.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, the compartment of terrain is provided with platform shape portion and structure on core bar, and platform shape portion is last, the structure infra, and the bottom surface of the deflector of structure and platform shape portion is faced each other; The syringe inboard then is provided with shoulder and following shoulder; The external diameter of platform shape portion is greater than the internal diameter of last shoulder, and the periphery of the upper surface of the platform shape portion face that is configured to tilt; Structure is set up and can passes through shoulder down but can not make progress downwards through last shoulder again.

Further, this structure is set to when disposable syringe being carried out the machine assembling, and structure can make the syringe strain and upwards push through down shoulder.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, deflector is full slice system or split blade type.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, deflector is circle, polygon, petal or bar shaped.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, core bar is the integral molded plastic molding.

In the preferred embodiments of the disposable syringe that second aspect of the present invention provides, deflector has thin root, thick edge.

The present invention also provides a kind of disposable syringe in the third aspect; Comprise needle stand, syringe and core bar, wherein comprise at least one the present invention on the core bar in the structure that first aspect provided, needle stand is provided with shoulder; When pulling back core bar, structure is set to pass through shoulder downwards.

In the preferred embodiments of a kind of disposable syringe that the third aspect provides, also comprise the support member that has central through hole in the present invention, support member is connected on the inboard of syringe, and needle stand is maintained between syringe and the support member; Comprising two structures on the core bar, is first structure in last structure, and the structure of infra is second structure, and first structure and second structure are towards identical; First structure is set to the time can upwards pass through shoulder in injection, can not pass through shoulder but finish in injection downwards when pulling back; Second structure is set to the time can upwards pass through central through hole in injection, can not pass through central through hole but finish in injection downwards when pulling back.

In the preferred embodiments of a kind of disposable syringe that the third aspect provides, the deflector of this structure is full slice system or split blade type in the present invention.

In the preferred embodiments of a kind of disposable syringe that the third aspect provides, the deflector of this structure is circle, polygon, petal and bar shaped in the present invention.

In the preferred embodiments of a kind of disposable syringe that the third aspect provides, core bar is the integral molded plastic molding in the present invention.

In the preferred embodiments of a kind of disposable syringe that the third aspect provides, deflector has thin root in the present invention, thick edge.

Structure provided by the invention; Both can be applicable on the pulling back of needle stand, and can be applicable to again on the kayser between core bar and the syringe, resistance with the kayser process can reduce to pull back; Make injection process more stable; The kayser process is more laborsaving, and assembling process is more simplified, and the manufacturing is convenient, with low cost.

Below will combine accompanying drawing that the technique effect of design of the present invention, concrete structure and generation is described further, to understand the object of the invention, characteristic and effect fully.

Description of drawings

Fig. 1 shows the structure that needle stand is pulled back that will be arranged in the prior art on the core bar.

Fig. 2 shows the latching structure between syringe and core bar in the prior art.

Fig. 3 shows the auxiliary assembling circle of assembling usefulness in the prior art.

Fig. 4 (a), Fig. 4 (b), Fig. 4 (c) and Fig. 4 (d) show a specific embodiment and its different conditions according to a kind of structure of the present invention.

Fig. 5 shows a specific embodiment according to the deflector of structure of the present invention.

Fig. 6 shows another specific embodiment according to the deflector of structure of the present invention.

Fig. 7 shows another specific embodiment according to the deflector of structure of the present invention.

Fig. 8 shows a specific embodiment of the core bar of the disposable syringe that has adopted structure of the present invention.

Fig. 9 show with Fig. 8 in a specific embodiment of the syringe that matches of core bar.

Sketch map when Figure 10 shows core bar and the syringe among Fig. 9 among Fig. 8 and is in the kayser state.

Figure 11 shows the enlarged drawing at A place among Figure 10.

Figure 12 shows an alternative embodiment at A place among Figure 11.

Figure 13 shows according to the structure applications of inventing in a specific embodiment at the needle stand place of disposable syringe.

Figure 14 shows structure according to the present invention and is arranged on an inboard embodiment of syringe.

Figure 15 shows another embodiment according to the deflector of structure of the present invention.

The specific embodiment

Fig. 4 shows the sketch map according to an embodiment of structure of the present invention; Wherein structure 100 comprises three parts successively: deflector 101, connecting portion 102, stop part 103; Wherein deflector 101 is set under external force; Deflection takes place in deflector 101 at root 104 places, make deflector 101 can go up deflect, shown in Fig. 4 (b) and Fig. 4 (c).Deflector 101 is preferably processed by having certain flexible material such as plastics, and when external force was removed, deflector 101 can roughly return back to the initial position shown in Fig. 4 (a) like this.The external diameter of this deflector 101 is greater than the external diameter of stop part 103.The external diameter of connecting portion 102 is less than the external diameter of deflector 101 and stop part 103; And the length of connecting portion 102; That is the spacing distance between deflector 101 and the stop part 103 is set to can not continue deflection to stop part 102 deflection meetings because of the stop part 103 of conflicting when deflector 101, and the deflector 101 after deflection this moment has formed the inclined-plane or the conical surface 105.When 105 are the conical surface (as when deflector 101 is circle), then deflector 101 generally is similar to the dish shapes at this moment.The gradient of the inclined-plane or the conical surface 105 or tapering can be adjusted through length that is the deflector 101 of adjustment connecting portion 102 and the spacing of stop part 103 and/or both external diameter differences.And this adjustment is conventional means to those skilled in the art.When deflector 101 during to the direction deflection opposite with stop part 103, owing to there is not the restriction of stop part 103, deflector 101 can free deflection.

Structure 100 common and critical point fit applications refer to through hole, shoulder, opening etc. at this critical point.The internal diameter at the critical point of matching with structure 100 is set to greater than the external diameter of stop part 103 less than the external diameter of deflector 101 usually; Like this when this structure is passed through this critical point with stop part 103 pro-; Stop part 103 and connecting portion 102 can have no to hinder passes through the critical point; And deflector 101 is under the effect at critical point, can be to the direction free deflection opposite with stop part 103, thereby like a cork through this critical point; And when this structure when the moved back, deflector 101 at first contact with the critical point, acts on deflect portion 101 at the critical point to stop part 103 deflections and be resisted against on the stop part 103, thereby can not continue deflection.And the inclined-plane or the conical surface 105 are set to when user carries out manual operation with the critical point; The inclined-plane or the conical surface 105 are trapped in the place, critical point and can not pass through; Yet when applying enough big external force on this structure 100 through means such as machines; The inclined-plane or the conical surface 105 can push through this critical point through making the critical point that strain take place, thereby make structure 100 through this critical point.Above-mentioned technique effect can be during fabrication as required; Through to the gradient of the inclined-plane or the conical surface 105 or tapering with make the critical point that elastically-deformable complexity etc. (relevant with the material at critical point, thickness etc.) take place to select to be provided with and realize; And this selection is conventional for a person skilled in the art, need not that any creative work can realize.

Structure 100 preferred integral molded plastics form, certainly also can be through assembled, and the thickness of deflector 101 is preferably between 0.2mm to 1.0mm, and the length of connecting portion 102, that is the spacing distance between deflector 101 and the stop part 103 is preferably less than 0.7mm.

Also can be set to be uniform thickness not to deflector 101 in addition; Shown in Fig. 4 (d); Can design the root 104 of deflector 101 thinner and form the inclined-plane or the conical surface 105 so that it is easier to deflection; Simultaneously can be with the marginal portion design of deflector 101 relatively thicker, like 1.5mm to 2.0mm, the inclined-plane or the conical surface 105 are more not yielding under the effect of critical point and stop part 103 like this.

Deflector 101 has multiple possible embodiment, like Fig. 5,6, the full slice system shown in 7 and multiple-piece, and circle or polygon, also have the bar shaped of band round end shown in figure 15 etc.For a person skilled in the art, embodiment that deflector 101 much is equal in addition such as petal, bar shaped, railing shape, oval or the like can also have single groove or have a plurality of grooves or the like on it, all should be within protection scope of the present invention.

Fig. 8-11 shows an embodiment who said structure 100 is applied to the kayser of 2 of disposable syringe core bar 1 and syringes.Like Fig. 8, shown in 11, the compartment of terrain is provided with two above-mentioned structures 100 on the core bar 1 of this disposable syringe, wherein the second structure 100b of first last structure 100a and infra towards on the contrary.Like Fig. 9, shown in 11; Be provided with shoulder 201 and following shoulder 202 syringe 2 clear widths; And wherein the external diameter of the first stop part 103a and the second stop part 103b all is less than or equal to shoulder 201 and following shoulder 202; And the external diameter of the first deflector 101a is greater than the internal diameter of last shoulder 201; The external diameter of the second deflector 101b is greater than the internal diameter of following shoulder 202, and the interval between the first deflector 101a and the second deflector 101b is more than or equal to said interval of going up between shoulder 201 and the following shoulder 202.For the ease of making, the size of the first structure 100a and each one of the second structure 100b is preferably identical separately; The internal diameter of last shoulder 201 and following shoulder 202 is preferably identical.And the second structure 100b is set to pass through shoulder 201 downwards when after injection finishes, pulling back core bar, but can not make progress through said shoulder 202 down again, and the said first structure 100a then is set to can not be downwards through shoulder 201 on said.

Adopted core bar and the syringe of above-mentioned setting can adopt mechanical assembling mode commonly used in the prior art to assemble, as joining, and need not to use auxiliary assembling circle at the enterprising luggage of ordinary syringe disc type automation kludge.This is because when assembling; The first stop part 103a of the first structure 100a can have no the ground of obstruction through last shoulder 201 and following shoulder 202; The first deflector 101a of the first structure 100a to the direction free deflection that deviates from the first stop part 103a and can be like a cork through last shoulder 201 and following shoulder 202; And the restriction that the second deflector 101b of the second structure 100b receives the periphery of the second stop part 103b because of its deflection to the second stop part 103b has formed the inclined-plane or the conical surface; Yet different with the inverted cone of snap flange among Fig. 2 202, under the effect of mechanical force and inertia force, the inclined-plane or the conical surface that the second deflector 101b forms are set to and can make syringe generation elastic deformation through the applied force that puts together machines; And shoulder 201 and following shoulder 202 in assembling process, pushing through fit in the syringe 2.When injection finishes when pulling back core bar 1; The inclined-plane of the first structure 100a and the second structure 100b or the conical surface all are set to push through through the power that operator's manual operation produces shoulder 201 or following shoulder 202, thereby have realized the kayser of 2 of core bar 1 and syringes.

Adopt this kayser mode, when assembling, can not re-use the assembling circle on the one hand, thereby save operation and cost, and fit is identical with common disposable syringe, can join at the enterprising luggage of existing automatic assembling machine.Pull back core bar 1 when carrying out kayser finishing using on the other hand, need not any rigid extrusion process, therefore whole pull back very little, easily laborsaving with kayser process resistance.

In addition; Also can the first structure 100a be replaced with external diameter shown in figure 12 platform shape portion 105 greater than last shoulder 201; Wherein the periphery of the upper surface of platform shape portion 105 is formed the face of inclination so that assemble; Since assembling the time need make platform shape portion 105 push through internal diameter less than it on shoulder 201, the resistance that need overcome when therefore this configuration makes assembling is bigger.

In addition; Also the first structure 100a can only be set on core bar 1; And shoulder 201 only is set on the syringe 2, this moment, the first structure 100a can prevent that still core bar 1 is drawn out syringe 2 when pulling back, promptly as the function of the bit-stopping structure on the ordinary syringe; And with respect to the bit-stopping structure on the ordinary syringe, it is more convenient laborsaving that the advantage of this set is that equally it assembles.

Figure 13 shows the embodiment pulling back of structure applications according to the present invention in needle stand; 3 is that needle stand, 2 is that syringe, 4 is that the support member, 5 that has central through hole 41 is the bar head of core bar 1 among the figure; Support member 4 is connected in the draw-in groove 25 on the syringe 2; Needle stand 3 is positioned between syringe 2 and the support member 4, also is provided with shoulder 32 in the endoporus 31 of needle stand 3.Shown in figure; The compartment of terrain is provided with the 3rd structure 100c and the 4th structure 100d on the bar head 5 of core bar 1; The 3rd structure 100c and the 4th structure 100d's wherein towards identical; And the external diameter of the 3rd stop part 103c is less than the internal diameter of the central through hole 41 of shoulder 32 and support member 4; The external diameter of the 4th stop part 103d is less than the internal diameter of the central through hole 41 of support member 4, and the external diameter of the 3rd deflector 101c is greater than the internal diameter of shoulder 32, and the external diameter of the 101d of quadrupole deflector portion is greater than the internal diameter of the central through hole 41 of support member 4.In addition, the external diameter of the 3rd deflector 101c also can be set to the internal diameter less than central through hole 41, and such the 3rd structure 100c can have no obstacle ground through central through hole 41.During injection; The 3rd deflector 101c of the 3rd structure 100c through the 101d of quadrupole deflector portion through 32, the four structure 100d of the shoulder in the endoporus 31 that is arranged on needle stand 3 to the direction free deflection that deviates from the 3rd stop part 103c and like a cork through the central through hole 41 through support member 4 to the direction free deflection that deviates from the 4th stop part 103d and like a cork.When after injection finishes, pulling back core bar 1; The 4th sheet shaped piece 101d of the 4th structure 100d is to the 4th stop part 103d deflection; Owing to receive the restriction of the 4th stop part 103d; The 4th sheet shaped piece 101d deflection slightly just has been resisted against on the periphery of the 4th stop part 103d, and then support member 4 is applied downward pulling force, and support member 4 and syringe 2 are broken away from.Likewise, the 3rd structure 100c is in the process of pulling back, and the 3rd deflector 101c that is resisted against on the 3rd stop part 103c retracts needle stand 3 in the syringe 2 through shoulder 32.

In the above embodiments; Owing to adopted according to structure of the present invention, the process resistance of central through hole 41 and the shoulder 32 of the bar head 5 of core bar 1 through support member 4 is very little, thereby the operator is operated very freely; Whole process is more stable, has reduced by injector's sense of discomfort.

Can be understood that structure 100 according to the present invention also can be arranged on the inwall of syringe 2 conversely by those skilled in the art, can shoulder with matching and on core bar 1, be provided with, to realize the kayser between core bar 1 and the syringe 2; Also can structure 100 according to the present invention be arranged on the central through hole 31 of needle stand 3 conversely, can shoulder with matching and on core bar 1, be provided with, to realize pulling back of 1 pair of needle stand 3 of core bar.Figure 15 shows structure 100 is arranged on an embodiment on the inboard of syringe 2.

Last direction described in the application or lower direction are meant the direction of the syringe needle or the core bar handle of said disposable syringe respectively; The external diameter of said deflector or stop part then is meant its greatest length transversely, and when deflector or stop part when being circular, said external diameter promptly is its diameter.The internal diameter of said central through hole or shoulder is central through hole or space greatest length in the horizontal that shoulder limited, when space that center through hole or shoulder limited when circular, said internal diameter promptly is its diameter.

More than describe preferred embodiment of the present invention in detail.Should be appreciated that those of ordinary skill in the art need not creative work and just can design according to the present invention make many modifications and variation.Therefore, all technical staff in the art all should be in the determined protection domain by claims under this invention's idea on the basis of existing technology through the available technical scheme of logical analysis, reasoning, or a limited experiment.

Claims

1. structure that is used for disposable syringe; Said structure comprises deflector, stop part; And the connecting portion that connects said deflector and said stop part; Said deflector can towards or deviate from said stop part and carry out deflection, when said deflector during towards said stop part deflection, said deflector is resisted against on the said stop part.

2. the structure that is used for disposable syringe as claimed in claim 1, wherein when said deflector was resisted against on the said stop part, said deflector formed the inclined-plane or the conical surface.

3. the structure that is used for disposable syringe as claimed in claim 1, wherein said deflector are full slice system or split blade type.

4. the structure that is used for disposable syringe as claimed in claim 1, wherein said deflector are circle, polygon, petal or bar shaped.

5. the structure that is used for disposable syringe as claimed in claim 1, wherein said deflector has thin root, thick edge.

6. the structure that is used for disposable syringe as claimed in claim 1, wherein said structure are the integral molded plastic molding.

7. the structure that is used for disposable syringe as claimed in claim 1, wherein said structure is arranged on the core bar of said disposable syringe.

8. the structure that is used for disposable syringe as claimed in claim 1, wherein said structure are arranged on the syringe inboard of said disposable syringe.

9. the structure that is used for disposable syringe as claimed in claim 1, wherein said disposable syringe also comprises needle stand, said structure is arranged on the inboard of the central through hole of said needle stand.

10. disposable syringe; Comprise syringe and core bar, comprise at least one structure as claimed in claim 1 on the wherein said core bar, said syringe inboard comprises at least one shoulder; When said structure was set to pull back said core bar, said structure can not be downwards through said shoulder.

11. disposable syringe as claimed in claim 10, wherein

On said core bar, comprising two said structures, is first structure in last said structure, and the said structure of infra is second structure, and said first structure and said second structure are towards on the contrary;

Said syringe inboard is provided with shoulder and following shoulder;

Be set to can be downwards through shoulder on said for said second structure when after injection finishes, pulling back said core bar, but can not make progress through said shoulder down again, and said first structure then is set to can not be downwards through shoulder on said.

12. disposable syringe as claimed in claim 11 is wherein carrying out machine when assembling to said disposable syringe, said second structure is set to upwards push through through making said syringe strain said shoulder and the following shoulder of going up.

13. disposable syringe as claimed in claim 10, wherein

The compartment of terrain is provided with platform shape portion and described structure on said core bar, and said shape portion be last, said structure infra, and the bottom surface of the said deflector of said structure and said shape portion is faced each other;

Said syringe inboard then is provided with shoulder and following shoulder;

The external diameter of said shape portion is greater than the said internal diameter of going up shoulder, and the periphery of the upper surface of said the shape portion face that is configured to tilt;

Said structure is set up and can goes up shoulder through said downwards, but can not make progress through said shoulder down again.

14. disposable syringe as claimed in claim 13, wherein said structure are set to when said disposable syringe being carried out the machine assembling, said structure can make said syringe strain and upwards push through said shoulder down.

15. disposable syringe as claimed in claim 10, wherein said deflector are full slice system or split blade type.

16. disposable syringe as claimed in claim 10, wherein said deflector are circle, polygon, petal or bar shaped.

17. disposable syringe as claimed in claim 10, wherein said core bar are the integral molded plastic molding.

18. disposable syringe as claimed in claim 10, wherein said deflector has thin root, thick edge.

19. disposable syringe; Comprise needle stand, syringe and core bar, comprise at least one structure as claimed in claim 1 on the wherein said core bar, said needle stand is provided with shoulder; When pulling back said core bar, said structure is set to can not be downwards through said shoulder.

20. like the said disposable syringe of claim 19, wherein

Also comprise the support member that has central through hole, said support member is connected on the inboard of said syringe, and said needle stand is maintained between said syringe and the said support member;

Comprising two said structures on the said core bar, is first structure in last said structure, and the said structure of infra is second structure, and said first structure and said second structure are towards identical;

Said first structure is set to can be upwards through said shoulder in when injection, can not be downwards through said shoulder when pulling back but finish in injection;

Said second structure is set to when injection, can upwards pass through said central through hole, can not be downwards through said central through hole when pulling back but finish in injection.

21. disposable syringe as claimed in claim 19, wherein said deflector are full slice system or split blade type.

22. disposable syringe as claimed in claim 19, wherein said deflector are circular, petal or bar shaped.

23. disposable syringe as claimed in claim 19, wherein said core bar are the integral molded plastic molding.

24. disposable syringe as claimed in claim 19, wherein said deflector has thin root, thick edge.