CN2724735Y - Self-destroying disposable syringe - Google Patents

Abstract

The utility model relates to a self-destroying disposable syringe, comprising a needle tube and a core rod. The core rod is divided into two parts: rod head and rod body. The front end of the rod head is covered by an elastic rubber stopper, while the rear end of the head rod is integrated with the rod body by a thin stick. A non-return bar, which is positioned at the non-return piece positioned at the rod head, is matched with the non-return slot, which is positioned at the front end inside the needle tube, to form a non-return structure. A stake post can also be arranged at the top of the rod head in order to reduce the residual liquid medicine in the liquid flowing through hole after injection. And a spacing piece is positioned at the rear end of core rod so as to prevent self-destruction before use due to the incorrect operation. The utility model has a simple and reasonable structure that it not only can realize the self-destroying technical effect of the syringe after single use, but also does not affect the fluidity and stability of the injection process, as safe and convenient as the traditional syringe, and can take full advantage of the liquid medicine avoiding waste and pollution.

Description

Re-use preventing once-used syringe

(technical field)

This utility model relates to a kind of medical apparatus and instruments, particularly a kind of disposible safety syringe with self-distruction structure.

(background technology)

Syringe is to need the often conventional medical apparatus and instruments of use in the curative activity.Because blood is the communication media of many infectious disease, so if same syringe is repeated to use on one's body the different patients, just be easy to cause transmission of disease, jeopardizes the public's health.In view of this, countries in the world all by the repeated use of legislation restriction syringe, are defined as disposable medical apparatus and instruments to syringe at present.But, because traditional disposable syringe is from technology with texturally can not stop people for cost saving it to be reused.Also have some in order to seek unlawful interests, the used discarded disposable syringe of special collection after flushing and repacking, flows into the medical market, once more for huge hidden danger has been buried in the diffusion and the propagation of numerous disease.In order to stop syringe to be repeated to use from technical standpoint, it is promptly being damaged after once using voluntarily, really accomplish and disposablely to use, there are many people to propose various technical schemes about re-use preventing once-used syringe, for example the ZL98246224.7 Chinese patent has just proposed a kind of technical scheme of re-use preventing once-used syringe, this scheme connects by changing being connected between the bar head of conventional syringe and the body of rod into thin neck shape, set up an elastic fin structure in bar head rear end, set up an annular convex shoulder at injection tube front end inner surface again, like this, when injecting use first normally, after the elastic fin structure of injection club head rear end is crossed the annular convex shoulder of injection tube inner surface, because elastic fin is blocked by convex shoulder, injection rod can not withdraw from backward, if firmly pull outward the body of rod, will cause the division of the body of rod and bar head, syringe is damaged, thereby guarantee that syringe can only be used once.To make syringe be the effect of self-destruction through once using though this scheme can reach, but the smooth and easy and safety that is unfavorable for injection process, because produce the obstacle sense when annular convex shoulder on the injection tube inner surface can make injection rod push ahead and be subjected to resistance sense, needing to increase firmly just can make bar head and elastic fin cross annular convex shoulder, and after bar head and elastic fin are crossed annular convex shoulder, need timely receipts power, in order to avoid the fltting speed of medicinal liquid is too fast, and elastic fin is extruded to cross when flicking suddenly behind the convex shoulder and can produces the spring effect, syringe is shaken, directly influence the smooth and easy of injection process, mild and stable, thus make this syringe convenient and safety not as conventional syringe in the use.

(utility model content)

The purpose of this utility model is to overcome the deficiencies in the prior art and defective, it is more reasonable to propose a kind of structure, can reach that to make syringe be the technique effect of self-destruction through once using, do not influence the smooth and easy and stable of injection process again, in the use the novel re-use preventing once-used syringe of convenience and safety as conventional syringe.

For reaching above-mentioned purpose, the utility model proposes a kind of re-use preventing once-used syringe, comprise syringe cylinder (1) and be contained in the interior syringe core rod (2) of syringe cylinder (1), wherein syringe core rod (2) is divided into bar head (3) and the body of rod (4) two parts, the flexible rubber stopper of front end sleeve (5) of bar head (3), link into an integrated entity with buttress shaft (6) between the rear end and the body of rod (4), perhaps with bar head (3), the buttress shaft (6) and the body of rod (4) are directly made one, the front end of bar head (3) also is with a resistance in elastic rubber plug (5) back and moves back sheet (7), and the periphery of sheet (7) is moved back in resistance or rear side extends outward lamellar or bar (8) is moved back in the resistance of column elasticity; Syringe cylinder (1) front end inboard laterally is provided with arcuation or groove (9) is moved back in the annular resistance; This arcuation or annular resistance are moved back groove (9) and are moved back bar (8) with the elasticity resistance and match, and make when syringe core rod (2) is pushed to the top of syringe cylinder (1), and the elasticity resistance is moved back bar (8) and can be slipped into to hinder and move back in the groove (9); Elasticity resistance is moved back bar (8) and is moved back groove (9) before slipping into resistance, it stretches that angle or length are propped up by the barrel of syringe cylinder (1) and can not full extension, slip into the resistance move back groove (9) after, elasticity resistance is moved back bar (8) and will fully be stretched and make it terminally to be moved back groove (9) by resistance and block, and moves back structure thereby form the resistance that stops syringe core rod (2) to be pulled back; This resistance is moved back the resistance that structure produces and is moved back the connection power that power is produced greater than buttress shaft (6), when the strength of the syringe core rod of pulling back (2) is enough big, it moves back the resistance power of moving back that structure produces with resistance and interacts, and will make buttress shaft (6) to the disconnection that is connected between bar head (3) and the body of rod (4).

Wherein, it is symmetrically arranged two that bar is moved back in the resistance of described elasticity, and perhaps evenly be provided with three or four, it is that groove is moved back in a circle annular resistance that groove is moved back in described resistance, perhaps moves back groove with the corresponding plurality of sections arcuation resistance of position and quantity that is provided with that bar is moved back in the elasticity resistance.The front end of described bar head (3) is provided with a draw-in groove (10), the rear end is provided with a lamellar base (11), elastic rubber plug (5) is provided with a Ka Tai (12) that can fasten with draw-in groove (10), by the snap-fit relationship between draw-in groove (10) and the Ka Tai (12) elastic rubber plug (5) is locked on bar head (3), resistance is moved back sheet (7) and is clamped between the lamellar base (11) of elastic rubber plug (5) and bar head (3) rear end.Elastic rubber plug (5), the combination that sheet (7) and bar head (3) are moved back in resistance can also change following structure into: the draw-in groove (10) that bar head (3) front end is provided with makes two draw-in grooves into, promptly go up draw-in groove (13) and lower bayonet slot (14), elastic rubber plug (5) is gone up and resistance is moved back and is provided with top fastening station (15) and the low fastening station (16) that a difference can fasten with last draw-in groove (13) and lower bayonet slot (14) on the sheet (7) separately, by the snap-fit relationship between last draw-in groove (13) and the top fastening station (15) elastic rubber plug (5) is locked on bar head (3), by the snap-fit relationship between lower bayonet slot (14) and the low fastening station (16) sheet (7) is moved back in resistance and be locked on bar head (3).

Described re-use preventing once-used syringe, on the position of top corresponding to syringe cylinder (1) nose-circle column liquid-through hole (17) of its bar head (3), can also be provided with an inserting column (18), the internal diameter and the length of the diameter of inserting column (18) and length and cylindric liquid-through hole (17) match; Described elastic rubber plug (5) front end is provided with a tract that matches with inserting column (18), makes the bar head (3) that is provided with inserting column (18) can put elastic rubber plug; When syringe core rod (2) was advanced to the top of syringe cylinder (1), inserting column (18) was filled in the cylindric liquid-through hole (17).

Described re-use preventing once-used syringe, the end in its body of rod (4) can also be provided with one and be used for restriction and syringe core rod (2) is advanced to makes elasticity resistance move back bar (8) to slip into arbitrary arcuation resistance and move back the banking stop (19) that groove (9) position is moved back in groove or annular resistance.

Described re-use preventing once-used syringe, sheet (7) part is moved back in its bar head (3) and resistance can also change following structure and combination into: bar head (3) is divided into upper boom head (20) and lower beam head (21) two bodies; Upper boom head (20) moves back sheet (7) with resistance and makes one; Upper boom head (20) rear end becomes the structure of engaging mutually with lower beam head (21) Front-end Design, this snap-in structure is that upper boom head (20) rear end or lower beam head (21) front end are provided with sphere, annular projection shape or barbed protuberances shape deck (22), lower beam head (21) front end or upper boom head (20) rear end are provided with sphere, ring-type concave shaped or the hook-shaped concave shaped draw-in groove (23) that fastens with deck (22), by this snap-in structure upper boom head (20) and lower beam head (21) are connected as one; Link into an integrated entity with buttress shaft (6) between lower beam head (21) rear end and the body of rod (4) or make one; Elastic rubber plug (5) is enclosed within upper boom head (20) front end.

Described re-use preventing once-used syringe, its bar head (3), resistance move back sheet (7) can also change following structure into buttress shaft (6) part: bar head (3) moves back sheet (7) with resistance and makes one; Buttress shaft (6) or its Front-end Design become deck structure (24), the position corresponding with deck (24) on the buttress shaft (6), the rear end of bar head (3) is provided with a draw-in groove (25) that fastens with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

Described re-use preventing once-used syringe, its bar head (3), the body of rod (4), buttress shaft (6) move back sheet (7) part with resistance and can also change following structure into: resistance is moved back on the buttress shaft (6) that sheet (7) is socketed in and the body of rod (4) is made one or link into an integrated entity; The front end of buttress shaft (6) is provided with a deck (24), the position corresponding with deck (24) on the buttress shaft (6), the rear end of bar head (3) is provided with a draw-in groove (25) that fastens with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

Described re-use preventing once-used syringe, its bar head (3), the body of rod (4), buttress shaft (6) move back sheet (7) part with resistance and can also change following structure into: buttress shaft (6) is divided into trisome with the bar head (3) and the body of rod (4) to be made, and resistance is moved back sheet (7) and made one with buttress shaft (6); The front-end and back-end of buttress shaft (6) are respectively equipped with a deck (24), the position corresponding with buttress shaft (6) front end deck (24), the rear end of bar head (3) is provided with a draw-in groove (25) that fastens with deck (24), the position that the front end of the body of rod (4) is corresponding with buttress shaft (6) rear end deck (24) also is provided with a draw-in groove (25) that fastens with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

This utility model compared with prior art has the following advantages:

1, simple in structure and reasonable, can reach that to make syringe be the technique effect of self-destruction through once using, do not influence the smooth and easy and stable of injection process again, safe and make things convenient for as conventional syringe in the use;

2, this utility model is provided with a syringe inserting column that matches with the syringe liquid-through hole in the club head position, can reduce the residual liquor of injecting in the back liquid-through hole that finishes, and avoids causing drug waste and environmental pollution.

(description of drawings)

Accompanying drawing 1 is the longitudinal sectional view of this utility model embodiment one;

Accompanying drawing 2 is longitudinal sectional views of the part parts of this utility model embodiment one;

Accompanying drawing 3 is longitudinal sectional views of this utility model embodiment two;

Accompanying drawing 4 is longitudinal sectional views of the part parts of this utility model embodiment two;

Accompanying drawing 5 is longitudinal sectional views of this utility model embodiment three;

Accompanying drawing 6 is longitudinal sectional views of the part parts of this utility model embodiment three;

Accompanying drawing 7 is this utility model embodiment two longitudinal sectional views when being provided with inserting column;

Accompanying drawing 8 is this utility model moves back groove in the inboard annular resistance that is provided with of syringe cylinder front end view in transverse section.

(specific embodiment)

Below in conjunction with drawings and Examples the specific embodiment of the present utility model is described.

Embodiment one: as depicted in figs. 1 and 2, this utility model provides a kind of re-use preventing once-used syringe, it comprises syringe cylinder (1) and is contained in the interior syringe core rod (2) of syringe cylinder (1) that wherein syringe core rod (2) is divided into bar head (3) and the body of rod (4) two parts; The upper front end of bar head (3) is provided with one and goes up draw-in groove (13), and the bottom is provided with a lower bayonet slot (14); The flexible rubber stopper of front end sleeve (5) of bar head (3), elastic rubber plug (5) is provided with a top fastening station (15) that can fasten with last draw-in groove (13), by the snap-fit relationship between last draw-in groove (13) and the top fastening station (15) elastic rubber plug (5) is locked on bar head (3); The front end of bar head (3) is with a resistance in elastic rubber plug (5) back and moves back sheet (7), resistance is moved back sheet (7) and is provided with a low fastening station (16) that can fasten with lower bayonet slot (14), by the snap-fit relationship between lower bayonet slot (14) and the low fastening station (16) sheet (7) is moved back in resistance and be locked on bar head (3), the rear side that sheet (7) is moved back in resistance extends outward two symmetrically arranged lamellar elasticity resistances and moves back bar (8); Be connected with buttress shaft (6) between the rear end of bar head (3) and the body of rod (4), and make one; Syringe cylinder (1) front end inboard laterally is provided with a circle resistance and moves back groove (9), and resistance is moved back groove (9) and moved back bar (8) with the elasticity resistance and match, and makes when syringe core rod (2) is pushed to the top of syringe cylinder (1), and the elasticity resistance is moved back bar (8) and can be slided into to hinder and move back in the groove (9); Elasticity resistance is moved back bar (8) and is moved back groove (9) before slipping into resistance, its spread length is propped up by the barrel of syringe cylinder (1) and can not full extension, slip into the resistance move back groove (9) after, elasticity resistance is moved back bar (8) and will fully be stretched and make it terminally to be moved back groove (9) by resistance and block, and moves back structure thereby form the resistance that stops syringe core rod (2) to be pulled back; This resistance is moved back the resistance that structure produces and is moved back the connection power that power is produced greater than buttress shaft (6), when the strength of the syringe core rod of pulling back (2) is enough big, it moves back the resistance power of moving back that structure produces with resistance and interacts, and buttress shaft (6) will be disconnected, thereby make disposable syringe generation self-destruction; The end of the body of rod (4) is provided with and is used for restriction and syringe core rod (2) is advanced to makes elasticity resistance move back bar (8) to slip into the banking stop (17) that groove (9) position is moved back in resistance, prevents from before use to make disposable syringe generation self-destruction owing to maloperation.

Embodiment two: as shown in Figure 3 and Figure 4, this utility model provides a kind of re-use preventing once-used syringe, and its basic structure is identical with embodiment one, and difference is: described bar head (3) is divided into upper boom head (20) and lower beam head (21) two bodies; Upper boom head (20) moves back sheet (7) with resistance and makes one; Upper boom head (20) rear end becomes the structure of engaging mutually with lower beam head (21) Front-end Design, this snap-in structure is that upper boom head (20) rear end is provided with globe holder (22), lower beam head (21) front end is provided with the spherical concave shaped draw-in groove (23) that fastens with globe holder (22), by this snap-in structure upper boom head (20) and lower beam head (21) is connected as one; Be connected with buttress shaft (6) between lower beam head (21) rear end and the body of rod (4), and make one.

Embodiment three: as shown in Figure 5 and Figure 6, this utility model provides a kind of re-use preventing once-used syringe, its basic structure is identical with embodiment one, difference is: described bar head (3) moves back sheet (7) with resistance and makes one, buttress shaft (6) is designed to deck structure (24), the position corresponding with deck (24), the rear end of bar head (3) is provided with a draw-in groove (25) that fastens with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.When syringe core rod (2) is pushed to the top of syringe cylinder (1), elasticity resistance is moved back bar (8) and is slipped into resistance and move back groove (9), elasticity resistance is moved back bar (8) and is fully stretched and make it terminally be moved back groove (9) by resistance and block, and moves back structure thereby form the resistance that stops syringe core rod (2) to be pulled back; This resistance is moved back resistance that structure produces and is moved back power greater than the power that engages between deck (24) and the draw-in groove (25), when the strength of the syringe core rod of pulling back (2) is enough big, it moves back the resistance power of moving back that structure produces with resistance and interacts, engagement connection between deck (24) and the draw-in groove (25) will be thrown off, bar head (3) moves back sheet (7) with resistance and then is stuck in the syringe and can't takes out, thereby this disposable syringe can not be reused; The top of bar head (3) also is provided with an inserting column (19) on the position corresponding to syringe cylinder (1) nose-circle column liquid-through hole (18), and the internal diameter and the length of the diameter of inserting column (19) and length and cylindric liquid-through hole (18) match; Described elastic rubber plug (5) front end is provided with a tract that matches with inserting column (19), makes the bar head (3) that is provided with inserting column (19) can put elastic rubber plug; When syringe core rod (2) was advanced to the top of syringe cylinder (1), inserting column (19) was filled in the cylindric liquid-through hole (18).

Claims (10)

1, a kind of re-use preventing once-used syringe, comprise syringe cylinder (1) and be contained in the interior syringe core rod (2) of syringe cylinder (1), wherein syringe core rod (2) is divided into bar head (3) and the body of rod (4) two parts, the flexible rubber stopper of front end sleeve (5) of bar head (3), link into an integrated entity with buttress shaft (6) between the rear end and the body of rod (4), perhaps with bar head (3), the buttress shaft (6) and the body of rod (4) are directly made one, it is characterized in that: the front end of bar head (3) also is with a resistance in elastic rubber plug (5) back and moves back sheet (7), and the periphery of sheet (7) is moved back in resistance or rear side extends outward lamellar or bar (8) is moved back in the resistance of column elasticity; Syringe cylinder (1) front end inboard laterally is provided with arcuation or groove (9) is moved back in the annular resistance; This resistance is moved back the resistance of groove (9) and elasticity and is moved back bar (8) and match, and makes when syringe core rod (2) is pushed to the top of syringe cylinder (1), and the elasticity resistance is moved back bar (8) and can be slided into resistance and move back in the groove (9); Elasticity resistance is moved back bar (8) and is moved back groove (9) before slipping into resistance, it stretches that angle or length are propped up by the barrel of syringe cylinder (1) and can not full extension, slip into the resistance move back groove (9) after, elasticity resistance is moved back bar (8) and will fully be stretched and make it terminally to be moved back groove (9) by resistance and block, and moves back structure thereby form the resistance that stops syringe core rod (2) to be pulled back; This resistance is moved back the resistance that structure produces and is moved back the connection power that power is produced greater than buttress shaft (6), when the strength of the syringe core rod of pulling back (2) is enough big, it moves back the resistance power of moving back that structure produces with resistance and interacts, and will make buttress shaft (6) to the disconnection that is connected between bar head (3) and the body of rod (4).

2, re-use preventing once-used syringe according to claim 1, it is characterized in that: described elasticity resistance is moved back bar (8) and is symmetrically arranged two, perhaps even three or four of being provided with, it is that groove is moved back in a circle annular resistance that groove (9) is moved back in described resistance, perhaps move back groove with the corresponding plurality of sections arcuation resistance of position and quantity that is provided with that bar (8) is moved back in elasticity resistance, the front end of described bar head (3) is provided with a draw-in groove (10), the rear end is provided with a lamellar base (11), elastic rubber plug (5) is provided with a Ka Tai (12) that can fasten with draw-in groove (10), by the snap-fit relationship between draw-in groove (10) and the Ka Tai (12) elastic rubber plug (5) is locked on bar head (3), resistance is moved back sheet (7) and is clamped between the lamellar base (11) of elastic rubber plug (5) and bar head (3) rear end.

3, re-use preventing once-used syringe according to claim 1, it is characterized in that: described elasticity resistance is moved back bar (8) and is symmetrically arranged two, perhaps even three or four of being provided with, it is that groove is moved back in a circle annular resistance that groove (9) is moved back in described resistance, perhaps move back groove with the corresponding plurality of sections arcuation resistance of position and quantity that is provided with that bar (8) is moved back in elasticity resistance, the upper front end of described bar head (3) is provided with one and goes up draw-in groove (13), the bottom is provided with a lower bayonet slot (14), elastic rubber plug (5) is gone up and resistance is moved back and is provided with top fastening station (15) and the low fastening station (16) that a difference can fasten with last draw-in groove (13) and lower bayonet slot (14) on the sheet (7) separately, by the snap-fit relationship between last draw-in groove (13) and the top fastening station (15) elastic rubber plug (5) is locked on bar head (3), by the snap-fit relationship between lower bayonet slot (14) and the low fastening station (16) sheet (7) is moved back in resistance and be locked on bar head (3).

4, according to claim 1,2 or 3 described re-use preventing once-used syringes, it is characterized in that: the end of the described body of rod (4) is provided with and is used for restriction and syringe core rod (2) is advanced to makes elasticity resistance move back bar (8) to slip into the banking stop (17) that groove (9) position is moved back in resistance.

5, according to claim 1,2 or 3 described re-use preventing once-used syringes, it is characterized in that: the top of described bar head (3) is provided with an inserting column (19) corresponding to the position of syringe cylinder (1) nose-circle column liquid-through hole (18), and the internal diameter and the length of the diameter of inserting column (19) and length and cylindric liquid-through hole (18) match; Described elastic rubber plug (5) front end is provided with a tract that matches with inserting column (19), makes the bar head (3) that is provided with inserting column (19) can put elastic rubber plug; When syringe core rod (2) was advanced to the top of syringe cylinder (1), inserting column (19) was filled in the cylindric liquid-through hole (18).

6, re-use preventing once-used syringe according to claim 1 is characterized in that: described bar head (3) is divided into upper boom head (20) and lower beam head (21) two bodies; Upper boom head (20) moves back sheet (7) with resistance and makes one; Upper boom head (20) rear end becomes the structure of engaging mutually with lower beam head (21) Front-end Design, this snap-in structure is that upper boom head (20) rear end or lower beam head (21) front end are provided with sphere, annular projection shape or barbed protuberances shape deck (22), lower beam head (21) front end or upper boom head (20) rear end are provided with sphere, ring-type concave shaped or the hook-shaped concave shaped draw-in groove (23) that can fasten with deck (22), by this snap-in structure upper boom head (20) and lower beam head (21) are connected as one; Link into an integrated entity with buttress shaft (6) between lower beam head (21) rear end and the body of rod (4) or make one; Elastic rubber plug is enclosed within upper boom head (20) front end.

7, re-use preventing once-used syringe according to claim 1 is characterized in that: described bar head (3) moves back sheet (7) with resistance and makes one; Buttress shaft (6) or its Front-end Design become deck structure (24), the position corresponding with deck (24) on the buttress shaft (6), the rear end of bar head (3) is provided with a draw-in groove (25) that can fasten with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

8, re-use preventing once-used syringe according to claim 1 is characterized in that: described resistance is moved back on the buttress shaft (6) that sheet (7) is socketed in and the body of rod (4) is made one or link into an integrated entity; The front end of buttress shaft (6) is provided with a deck (24), the position corresponding with deck (24) on the buttress shaft (6), the rear end of bar head (3) is provided with a draw-in groove (25) that can fasten with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

9, re-use preventing once-used syringe according to claim 1 is characterized in that: described buttress shaft (6) is divided into trisome with the bar head (3) and the body of rod (4) to be made, and resistance is moved back sheet (7) and made one with buttress shaft (6); The front-end and back-end of buttress shaft (6) are respectively equipped with a deck (24), the position corresponding with buttress shaft (6) front end deck (24), the rear end of bar head (3) is provided with a draw-in groove (25) that can fasten with deck (24), the position that the front end of the body of rod (4) is corresponding with buttress shaft (6) rear end deck (24) also is provided with a draw-in groove (25) that can fasten with deck (24), utilizes the snap-fit relationship between deck (24) and the draw-in groove (25) that the bar head (3) and the body of rod (4) are linked into an integrated entity.

10, according to claim 6,7,8 or 9 described re-use preventing once-used syringes, it is characterized in that: the top of described bar head (3) or upper boom head (20) is provided with an inserting column (19) corresponding to the position of syringe cylinder (1) nose-circle column liquid-through hole (18), and the internal diameter and the length of the diameter of inserting column (19) and length and cylindric liquid-through hole (18) match; Described elastic rubber plug (5) front end is provided with a tract that matches with inserting column (19), makes the bar head (3) or the upper boom head (20) that are provided with inserting column (19) can put elastic rubber plug; When syringe core rod (2) was advanced to the top of syringe cylinder (1), inserting column (19) was filled in the cylindric liquid-through hole (18); The end of the described body of rod (4) can also be provided with and be used for restriction and syringe core rod (2) is advanced to makes elasticity resistance move back the banking stop (17) that bar (8) slips into resistance groove (9) position.

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