WO2005065755A1

WO2005065755A1 - Disposable safety syringe

Info

Publication number: WO2005065755A1
Application number: PCT/CN2004/001433
Authority: WO
Inventors: Hsienwen Hsieh
Original assignee: Hsienwen Hsieh
Priority date: 2003-12-30
Filing date: 2004-12-10
Publication date: 2005-07-21
Also published as: CN2668144Y

Abstract

The invention provides a kind of disposable safety syringe, which includes a cylinder (1) a plunger (2), a piston (3) mounted on the front end of the plunger and a pinhead (4). The pinhead (4) is mounted on a pinhead base (11) which is on the front end of the cylinder (1); The pinhead (4) includes a needle base (41), a needle cover (42), a needle (43) and a spring (45); The needle cover (42) includes a step on its rear end and a through hole in its center; The needle (43) is mounted on the front part of the through hole of the needle cover (42); The needle base (41) has a through chamber in its center where the spring (45) is mounted in, and there is a fitting connect device between the needle base (41) and the pinhead base (11) ; A sealing ring is mounted between the step of the rear end of said needle cover and the distal end of the chamber of the needle base (41), a top ring (21) corresponding to the sealing ring (44) is on the front end of the plunger (2). When the injection is completed, the safety syringe has no medicine residue, and can be self-destructed, after that, it can not be reused.

Description

Single-use safety syringes

The invention relates to a syringe in the field of medical equipment, and in particular to a disposable safety syringe. Background technique

It is well known that a syringe is a commonly used medical device. To prevent cross-infection, the disposable use of syringes is receiving increasing attention. However, existing syringes generally do not have a self-destructive protective structure, so that existing syringes are not strictly "disposable" in terms of performance, and can be used repeatedly, leaving hidden dangers to cross-infection. Causes the spread of disease. In addition, during the processing of the existing syringe after the injection is completed, the exposed needle can easily puncture or scratch people around it, causing new cross infection.

The Chinese patent No. 98250220.6 safety syringe is composed of a syringe, a needle assembly, a snap seat, a push rod and a chuck. The snap-in seat is located at the front end of the syringe, and the needle assembly is combined with the tip of the snap-in seat. An engaging hole is provided at the rear end of the engaging seat. The chuck is arranged at the front end of the push rod. When the push rod is advanced toward the front end of the injection cylinder to the front end, the chuck engages with the engagement seat. When the push rod is pulled out backward, the engaging seat together with the needle assembly is pulled into the accommodating chamber of the syringe to prevent the needle from stabbing the human body and achieving the purpose of single use. However, due to the irrational design structure of the syringe, there are technical defects such as large residual amount of liquid medicine and incomplete seal after injection, and its product performance is not stable enough, and it does not conform to national regulations on the amount of residual liquid medicine. Regulations.

A patent application of WO 02/087669 also discloses a safety syringe, which includes a needle tube, a needle tube sleeve, a needle tube seat, a sealing element, and a spring. It has the function of automatically destroying the syringe after the injection is completed. However, the structure of the syringe is too complicated, which increases the production cost. In addition, this structure also causes a defect that a large amount of chemical liquid remains. Moreover, when the safety syringe is in use, after the injection operation is completed, before the medical staff removes the needle from the patient, the needle will automatically eject from the patient and enter the syringe, thereby causing great pain to the patient. . Therefore, practicability is poor. Summary of the invention

The object of the present invention is to provide a disposable safety syringe with a protective self-destructive structure and a complete injection of a medicinal solution in view of the defects existing in the existing syringes.

The disposable safety syringe of the present invention comprises: a syringe; a push rod provided in the syringe, which has a portion that fits with the inner wall of the syringe, and can slide along the inner wall of the syringe; The front end of the syringe is integrally formed with a needle base; and

A needle part is mounted on the needle base, and the needle part includes: a needle base, a needle sleeve, Brazed tube and spring;

The rear end of the needle tube sleeve has a cylindrical step, the center of which is a through hole; the needle tube is installed in the through hole of the needle tube sleeve, and its needle tip protrudes from the needle tube sleeve; the center of the needle tube base is through A cavity, the spring is installed in the cavity of the needle tube base, and the needle tube base and the needle base have a mating connection structure, which is characterized in that: it is installed on the outer end surface of the cylindrical step at the rear end of the needle tube sleeve; A seal lock ring is provided, and the seal lock ring is clipped on the end of the cavity of the needle tube seat. The front end of the push rod has a top ring, and the top ring corresponds to the seal lock ring.

Since the safety syringe is completely in contact with the bottom of the syringe when the injection is completed, the drug liquid is prevented from remaining. In addition, due to the special needle structure, it is conducive to the protective self-destruction of the entire syringe and truly achieves the purpose of one-time use.

Pi illustrated in the figure

FIG. 1 is a schematic diagram of an appearance of a syringe according to a first embodiment of the present invention;

2 is a schematic sectional view of an internal structure of a syringe according to a first embodiment of the present invention;

3 is a schematic cross-sectional view of a needle holder according to a first embodiment of the present invention;

4 is a schematic cross-sectional view of a needle cannula according to a first embodiment of the present invention;

5 is a schematic cross-sectional view of a syringe according to a first embodiment of the present invention;

6 is a sectional view of a top ring according to a first embodiment of the present invention;

7 is a top view of a top ring according to a first embodiment of the present invention;

8 is a schematic cross-sectional view of a putter support according to an embodiment of the present invention;

9 is a cross-sectional view of a portion of a putter with a thrust boss according to an embodiment of the present invention;

FIG. 10 is a schematic cross-sectional view of an internal structure of a syringe according to a second embodiment of the present invention. detailed description

As shown in FIGS. 1 and 2, the disposable safety syringe according to the first embodiment of the present invention includes a syringe 1, a push rod 2, a push rod piston 3, and a needle portion 4. Push rod piston 3 is installed at the front of push rod 2 • ^. The largest part of the outer diameter of the push rod piston 3 coincides with the inner wall of the syringe 1 and can slide longitudinally along the inner wall. A needle base 11 is provided at the front end of the syringe 1, and the needle base 11 and the syringe 1 can be integrally injection-molded during processing. The needle portion 4 is mounted on a needle base 11. This part of the technology is similar to the existing syringes, which will not be described in detail in JT.

As shown in FIG. 2, the needle part 4 includes a needle tube holder 41, a needle tube cover 42, a needle tube 43, a seal lock ring 44, and a spring 45.

As shown in FIG. 2 and FIG. 3, the center of the needle tube holder 41 is a through cavity 411. The cavity can accommodate the needle tube sleeve 42 and allow the needle tube sleeve 42 to slide in the longitudinal direction. A step 412 is formed at the middle position of the inner wall of the cavity 411 of the needle holder 41, so that the diameter of the cavity 411 in the front half of the needle holder 41 is smaller than the rear Half the diameter. A hollow cylindrical body 415 extends from the end surface of the rear end portion of the needle tube base 41 integrally with the needle tube base 41. The cylindrical body 415 is concentric with the needle tube base 41, and its inner diameter closely matches the outer diameter of the sealing and locking ring 44. Its height is greater than or equal to The height of the seal lock ring 44 is twice. In this embodiment, the height of the cylinder 415 is equal to twice the height of the seal lock ring 44. The outer cylindrical surface 416 of the cylinder 415 is a conical surface. An external thread 413 is provided on the outer circumferential surface of the joint where the cylinder 415 and the needle tube seat 41 are connected. Under the push of the push rod 2, in order to prevent the needle tube cover 42 from sliding forward, a front end of the cavity of the needle tube holder 41 is provided with a stopper 46 that shrinks toward the center.

As shown in FIG. 2 and FIG. 4, the needle tube cover 42 has a hollow shape, and a longitudinal through hole 421 is formed in a central portion thereof. The rear end of the needle cannula 42 forms a cylindrical step 422 protruding radially. The needle tube 43 is installed in the through hole 421 of the needle tube cover 42, and the bottom surface thereof is flush with the bottom surface 427 of the needle tube cover 42, which further reduces the residual drug solution during injection. The needle tip 431 projects beyond the needle cannula 42 for easy injection. The needle tube 43 is adhered to the needle tube cover 42. During injection, the needle tube 43 does not shrink into the needle tube cover 42. The diameter of the front end of the through hole 421 varies, and is composed of the following five through holes: First, a cylindrical through hole 424 is formed inward from the front surface 423, and the cylindrical through hole 424 extends inward to form a conical through hole 425. The conical through-hole 425 extends inwardly with a spherical through-hole 426, the spherical through-hole 426 extends inwardly with a cylindrical through-hole 427, and finally, the cylindrical through-hole 427 extends inwardly to form a cylindrical through-hole 428. Among them, the diameter of the through-hole 428 is the smallest among all the through-holes, which is the same as the outer diameter of the needle tube 43 and the two are a tight fit. The center diameter of the spherical through hole 426 is the same as the diameter of the cylindrical through hole 424, and the diameters of the two ends are the same as the diameters of the small end of the cylindrical through hole 427 and the conical through hole 425. It is smaller than the diameter of other parts of the through hole 421. The design of the above-mentioned variable diameter is to enable the glue to smoothly enter the inner wall surfaces of the through holes 424, 425, 426, 427 when the needle tube 43 and the needle tube sleeve 42 are being glued, and form a stack in the spherical through hole 426, so that The needle tube 43 can be more firmly bonded in the through hole 421.

As shown in FIG. 2, the seal lock ring 44 has a ring shape, is mounted on the outer end surface of the cylindrical step 422 at the rear end portion of the needle tube sleeve 42, and is clamped at the rear end portion of the cavity 411 of the needle tube holder 41. That is, the seal lock ring 44 is clamped between the outer end surface of the cylindrical step 422 at the rear end portion of the needle tube sleeve 42 and the end portion of the cavity 411 of the needle tube holder 41. The seal lock ring 44 guarantees the seal between the needle tube sleeve 42 and the needle tube holder 41 on the one hand, and fixes the needle tube sleeve 42 (along with the needle tube 43) on the needle tube holder 41 on the other hand. In a preferred embodiment of the present invention, in order to reduce the friction between the sealing lock ring 44 and the needle tube sleeve 42 and the needle tube holder 41, its outer circumferential surface is a conical surface, and its diameter is One end began to shrink gradually.

The spring 45 is installed between the inner wall of the cavity 411 of the needle tube holder 41 and the outer wall of the needle tube sleeve 42. One end thereof is pressed on the cylindrical step 422 at the rear end of the needle tube sleeve 42, and the other end is pressed on the step 412 on the inner wall of the cavity 411 of the needle tube holder 41. The length from the step 422 to the step 412 is smaller than the length of the spring 45. Therefore, under normal circumstances, the spring 45 is in a compressed force state. When the sealing lock ring 44 is pushed open, When it is detached from the outer end surface of the rear end step 422 of the needle tube cover 42, the restraint of the spring 45 will be released, and the needle tube cover 42 (together with the needle tube 43) will spring back by the elastic force of the spring 45. The needle tube base 41 and the needle base 11 at the front end of the syringe 1 have a connection structure that cooperates with each other.

As shown in FIG. 5, the syringe 1 is a hollow cylinder, and a needle base 11 is integrally extended at a connection portion between the front portion and the needle base 41. The needle base 11 is a hollow cylinder concentric with the syringe 1 and is provided with an internal thread on an inner wall surface 111 of a front end thereof; and an inner wall surface 112 of a rear end thereof is a round male surface. A conical surface 12 is formed on the inner wall surface of the rear end of the syringe 1.

As shown in FIG. 3 and FIG. 5, the fitting connection structure between the needle holder 41 and the needle holder 11 at the front end of the syringe 1 may be a spiral connection structure. In this embodiment, the needle holder 11 is an internal screw, and the needle holder 41 is Outer spiral. Of course, the needle base 11 may be an external spiral, and the needle base 41 may be an internal spiral. The conical surface of the inner wall surface 112 at the rear end of the needle base 11 is matched with the conical surface of the cylindrical body 415 of the needle tube base 41 and the outer cylindrical surface 416 of the needle tube base 41. Therefore, a tight fit can be generated when the needle base 41 and the needle base 11 are connected, and after the needle base 41 and the needle base 11 are screwed to each other, the end portion of the cavity 411 of the needle base 41 can generate a sealing lock ring 44. The radial pressure makes the sealing and locking ring 44 more tightly installed between the step 422 of the rear end portion of the needle tube sleeve 42 and the end portion of the cavity 411 of the needle tube holder 41.

In another embodiment of the present invention, the above-mentioned mating connection structure is an embedded card mounting structure. The front end 111 of the needle base 11 is a built-in bayonet, and the rear end 413 of the needle base 41 is a bayonet that matches the bayonet.

When assembling the above structure of the present invention, the needle tube base 41 is assembled with the needle base 11 through its mating structure.

As shown in FIG. 2, FIG. 6 and FIG. 7, the front end of the push rod 2 has a top ring 21. The top ring 21 corresponds to the seal lock ring 44 and is used to advance the seal lock ring 44 in the needle holder 41 forward. When the sealing lock ring 44 is pushed away from the rear end step 422 of the needle tube sleeve 42 by the top ring 21, the constraint on the needle tube sleeve 42 can be released, and the needle tube sleeve 42 can rebound backward under the action of the spring 45. The top ring 21 is a ring that can be formed integrally with the push rod 2. At least one notch 211 is provided on an end surface of the end opposite to the seal lock ring 44. When the top ring 21 bears against the seal lock ring 44, the medicinal solution in the syringe 1 can enter the needle tube 43 through the notch 211, so that After the injection is completed, the amount of liquid remaining in the syringe 1 is minimized. In the present preferred embodiment, two notches 211 are defined in the top ring 21. The height of the top ring 21 is equal to or greater than the height of the seal lock ring 44. In this embodiment, the height of the top ring 21 is equal to the height of the seal lock ring 44. The inner diameter of the top ring 21 is slightly larger than the inner diameter of the seal lock ring 44, and its outer diameter is slightly smaller than the outer diameter of the close ring 44. Therefore, it can be ensured that when the top ring 21 pushes the seal lock ring 44, it will not rub against the inner cylindrical surface of the cylinder 415 and the outer cylindrical surface of the rear end step 422 of the needle tube sleeve 42, and generate friction resistance.

As shown in FIG. 2, FIG. 5, FIG. 8, and FIG. 9, in order to prevent the top ring 21 of the push rod 2 from being accidentally pushed to push the seal lock ring 44 to slide forward to release the restriction of the spring 45, a rear end of the syringe 1 is provided with Limited Bit function putter support 6. The push rod support 6 is a cylinder with a through hole 61 in the middle. The diameter of the through hole 61 is slightly larger than the diameter of the push rod 2, so that the push rod 2 can be inserted into the through hole 61 and can slide in the through hole. The outer wall surface 63 of the hollow cylinder provided with the push rod support 6 inside the syringe 1 is a conical surface, and the inner wall surface 12 of the syringe 1 and the conical surface 63 of the push rod support 6 is also in contact with the outer wall surface 63. The matching conical surface, and the small end diameter of the inner wall surface 12 is smaller than the large end diameter of the outer wall surface 63. Thereby, the push rod holder 6 can be locked at the rear end of the syringe 1 without being pushed into the syringe 1. At least one thrust groove 62 is provided on the inner wall surface of the hollow cylindrical portion of the push rod support 6 provided outside the syringe 1, and the circumferential surface at the corresponding position at the rear end of the push rod 2 is provided with the thrust groove 62. Mating thrust boss 22. When the syringe is not in use or when a medical staff member pulls the push rod 2 forward in order to suck the liquid medicine, the thrust projection 22 of the push rod 2 faces the thrust groove 62 of the push rod support 6 and pushes the pusher forward After the lever 2, the thrust boss 22 will be blocked by the thrust groove and cannot continue to advance forward, thereby ensuring that the sealing lock ring 44 cannot be accidentally pushed out by the top ring 21. When the injection is performed, it is only necessary to stagger the thrust boss 22 and the thrust groove 62 and then push the push rod 2, that is, make the thrust boss 22 face the inner wall surface of the hollow cylindrical portion of the push rod support 6. The other part of the non-thrust groove 62 is pushed to perform injection.

After the injection is completed, the top ring 21 pushes the seal lock ring 44 away from the rear end step 422 of the needle tube sleeve 42 to release the constraint on the spring 45. Since the height of the top ring 21 is the same as the height of the seal lock ring 44, when the top ring 21 completely pushes the seal lock ring 44 away from the rear end step 422 of the needle tube sleeve 42, the bottom surface 23 of the top ring 21 is exactly the same as the height of the needle tube sleeve 42. The end surface 429 is in contact with each other, so that the needle tube cover 42 and the needle tube 43 can be kept still. When the needle tip 431 is pulled out of the patient and the push rod 2 is pulled back, the needle tube sleeve 42 (together with the needle tube 43) is elastically acted by the spring 45, and will automatically retract into the syringe following the pull-back action of the push rod 2. 1 within.

As shown in FIG. 2, after the injection of the syringe of the present invention is completed, the plunger piston 3 is completely in contact with the bottom of the syringe 1, because the shape of the plunger piston 3 matches the shape of the inner wall of the syringe 1, and is in the top ring 21 is provided with a notch 211, so that the medicinal solution outside the top ring 21 can enter the inner portion of the top ring 21 from the notch 211 and be injected into the needle tube 43, thereby avoiding the residue of the medicinal solution.

After one-time use, push the push rod 2 again, because the needle tube sleeve 42 rebounds into the syringe 1, the needle tube sleeve 42 cannot be positioned, which can prevent reuse. It may also be crushed because the needle tube sleeve 42 and / or the needle tube 43 push against the stopper 46 when the push rod 2 is pushed forward again and cannot protrude from the top opening of the needle tube holder 41. At the same time, the push rod 2 can be broken to make the entire syringe unusable, so that the syringe can only be used for one time and self-destructed, so as to avoid repeated use of the syringe.

As shown in FIG. 10, in the second embodiment of the present invention, a cavity 25 is provided at the front of the push rod 2. A sealing plug 24 is provided at the rear of the top ring 21 of the push rod 2, and the sealing plug 24 has a sealing performance to prevent the medicinal solution from penetrating into the cavity 25. When the injection is completed, the top ring 21 pushes the sealing and locking ring 44 to slide forward, releases the restriction on the spring 45, and causes the needle tube sleeve 42 to rebound backward under the action of the spring 45. Simultaneously, The plug 24 in the push rod 2 is pushed back into the cavity 25 by the needle tube sleeve 42, and the needle tube sleeve 42 is automatically popped into the cavity 25, so that the injection needle and the entire syringe cannot be used repeatedly, thereby realizing that the syringe is only used for one time And self-destruct, to avoid reuse of the syringe.

In summary, the present invention is a controllable self-destructive behavior. Since the rebound of the needle tube 43 of the present invention is performed after the needle tip 431 is pulled out of the patient, it will not cause pain to the patient, and it can overcome the syringe disclosed in WO 02/087669 when the needle tube rebounds. Bringing painful residual problems to patients. ^{,,, A} , '',

Claims

Rights request:

1. Single-use safety syringes, including:

Syringe (1);

A push rod (2), which is arranged in the syringe (1) and has a portion that coincides with the inner wall of the syringe (1), and can slide along the inner wall of the syringe;

A needle base (11) is integrally formed at the front end of the syringe (1); and

A needle part (4) is mounted on the needle base (11), and the needle part (4) includes a needle tube base (41), a needle tube cover (42), a needle tube (43) and a spring (45);

The rear end of the needle tube sleeve (42) has a cylindrical step (422), the center of which is a through hole (421); the needle tube (43) is installed in the through hole (421) of the needle tube sleeve (42), And its needle tip (431) protrudes from the needle tube cover (42); the center of the needle tube seat (41) is a through cavity (411), and the spring (45) is installed in the cavity of the needle tube seat (41) ( In 411), the needle tube base (41) and the needle base (11) have a mating connection knot, which is characterized in that: the outer end surface of the cylindrical step (422) at the rear end of the needle tube sleeve (42) A sealing lock ring (44) is installed on the top, and the sealing lock ring (44) is clamped on the end of the cavity (411) of the needle tube seat (41), and the front end of the push rod (2) has a top ring ( 21), the top ring (21) corresponds to a seal lock ring (44).

2. The syringe according to claim 1, characterized in that the top ring (21) is an annular body, and at least one notch (211) is provided on an end surface of the top ring (21) opposite to the sealing lock ring (44). .

3. The syringe according to claim 1, characterized in that the sealing lock ring (44) is a circular body.

4. The syringe according to claim 1, characterized in that the height of the top ring (21) is greater than or equal to the height of the seal lock ring (44); its outer diameter is smaller than the outer diameter of the seal lock ring (44), and The inner diameter is larger than the inner diameter of the lock ring (44).

The syringe according to claim 3, characterized in that the outer circumferential surface of the seal lock ring (44) is a conical surface whose diameter gradually decreases from an end facing the top ring (21).

6. The syringe according to claim 1, characterized in that the cavity (411) of the needle tube holder (41) has a step (412) in the cavity (411); the spring (45) is installed at the rear end of the needle tube sleeve (42) Between the step (422) and the step (412) in the cavity of the needle tube seat (41).

7. The syringe according to claim 1, wherein the diameter of the front end of the through hole (421) is changed and is composed of the following five through holes: First, a cylinder is formed inward from the front end surface (423). A through-hole (424), a cylindrical through-hole (424) extending inwardly to form a conical through-hole (425), a conical through-hole L (425) extending inwardly with a spherical through-hole (426), a spherical through-hole ( 426) A cylindrical through hole L (427) is further extended inward. Finally, the cylindrical through hole (427) is extended inward to form a cylindrical through hole (428).

8. The syringe according to claim 5, characterized in that the diameter of the through hole (428) is The diameter of the through hole is the smallest, which is the same as the outer diameter of the needle tube (43). The two are a tight fit. The center diameter of the spherical through hole (426) is the same as the diameter of the cylindrical through hole (424). The diameters are respectively the same as the diameters of the small ends of the cylindrical through-hole (427) and the conical through-hole (425). The diameters of the above five through-holes are smaller than those of other parts of the through-hole (421).

9. The syringe according to claim 1, wherein the needle base (11) is a hollow cylinder concentric with the syringe (1), and an internal thread is provided on an inner wall surface (111) of a front end thereof; The inner wall surface (112) at the rear end is a conical surface.

10. The syringe according to claim 1, characterized in that a hollow cylinder (415) is integrally extended on the end surface of the rear end of the needle tube base (41) with the needle tube base (41), and the cylinder ( 415) Concentric with the needle holder (41), its inner diameter is a tight fit with the outer diameter of the seal lock ring (44), its height is greater than or equal to twice the height of the seal lock ring (44), and the outer cylinder of the cylinder (415) The surface (416) is a conical surface matched with the inner wall surface (112) at the rear end of the needle base (11).

11. The syringe according to claim 1, characterized in that the fitting connection structure of the needle base (11) and the needle tube base (41) is a threaded connection; the needle base (11) is an internal thread, and the needle tube base (41) ) Is an external thread or the needle base (11) is an external thread, and the needle tube base (41) is an internal thread.

12. The syringe according to claim 1, characterized in that the mating connection structure of the needle base (11) and the needle tube base (41) is an embedded bayonet structure, and the needle base (11) is an bayonet bayonet The needle tube seat (41) is a clamping tooth matched with the bayonet.

13. The syringe according to claim 1, characterized in that a front end edge of the cavity of the needle tube seat (41) has a stopper (46) which shrinks toward the center.

14. The syringe according to any one of claims 1 to 13, characterized in that a push rod support (6) with a limited position function is provided between the rear end of the push rod (2) and the syringe (1). ).

15. The syringe according to claim 14, characterized in that the push rod support (6) is a cylinder with a through hole (61) in the middle, and the push rod support (6) is arranged on the syringe (1) The outer wall surface (63) of the inner hollow cylinder is a conical surface, and the inner wall surface (12) of the syringe (1) that contacts the conical surface (63) of the push rod support (6) is also an outer wall surface (63) The matching conical surface, the small end diameter of the inner wall surface (12) is smaller than the large end diameter of the inner wall surface (63), and the push rod support (6) is arranged on the inner wall surface of the hollow cylindrical portion outside the syringe (1) At least one thrust groove (62) is provided, and a thrust protrusion 22 matching with the thrust groove 62 is provided on a circumferential surface at a corresponding position at the rear end of the push rod (2).

16. The syringe according to claim 1, characterized in that the front part of the push rod (2) has a cavity (25), and the back part of the push rod top ring (21) has a sealing plug (24).