WO2012126341A1

WO2012126341A1 - Disposable injector

Info

Publication number: WO2012126341A1
Application number: PCT/CN2012/072526
Authority: WO
Inventors: 江波
Original assignee: 常州和康医疗器材有限公司
Priority date: 2011-03-18
Filing date: 2012-03-19
Publication date: 2012-09-27
Also published as: WO2012126342A1; CN102688544A; CN202637628U; CN202844270U; CN102688545A

Abstract

A disposable injector comprising a needle base (1), a syringe (2), and a core rod (4, 41, and 42), also comprising a support element (3). The support element (3) is fixed on the syringe (2), allowing the needle base (1) to be fixed relative to the syringe (2). The support element (3) and the core rod (4, 41, and 42) are configured such that when the core rod (4, 41, and 42) is pulled back, the core rod (4, 41, and 42) acts on the support element (3) and allows the support element (3) to be detached from the syringe (1).

Description

Disposable syringe

Technical field

The present invention relates to a disposable syringe, and more particularly to a disposable syringe that can be used to pull the needle back into the barrel after use.

Background technique

In order to avoid cross-infection when entering or removing media from humans or animals, the hypodermic syringe must be used once and disposed of as waste after use. The most widely used disposable syringes today consist of a hollow cylinder, a needle, and a fixed-range piston that fits within the barrel. The biggest problem with this kind of syringe is that after the injection is completed, the needle remains outside, which not only causes inconvenience to the handling and destruction of the syringe garbage, but also may injure the medical staff due to carelessness, resulting in the secondary cross of the bacteria. Infection, becoming a medical hazard that cannot be ignored, so there is a disposable syringe that can be retracted by a needle. .

Chinese patent CN1803212 Disclosed is a 'safety self-destructing medical injector' comprising a syringe and a hub, wherein the syringe and the hub are connected to each other by an annular boss disposed outside the hub and an annular groove disposed inside the syringe. The defect of the structure is that when the needle holder is manually pulled, the annular boss and the annular groove are separated from each other, and the resistance to be overcome is large, which is very laborious and difficult to operate, and the assembly is difficult, and the assembly is easy to be caused by excessive force. The annular boss directly passes over the annular groove and causes assembly failure.

PCT Patent Application PCT/CN2010/000520 A 'tip retractable disposable safety syringe' is disclosed in which the needle hub is positioned relative to the syringe by a stop boss structure between the needle hub and the syringe and a self-destructing dam. The support leg of the self-destructing bar is connected to the recess in the inner side of the barrel. During the retraction of the needle seat, the self-destructing bar is deformed by force and disconnected from the dimple, thereby allowing the needle seat to retract into the syringe. Such a structure still has some drawbacks, such as the need to align and insert the support legs of the self-destructing bar with the pits on the syringe, which increases the difficulty of assembly. When the injection is self-destructing, the supporting force of the needle holder is insufficient, so that the needle is not stable enough during the injection, and the process of retracting the needle still needs to overcome the resistance caused by the stop boss.

During the injection process, the needle is subjected to the reaction force of the body of the injected person to generate pressure into the needle hub, and the needle seat is required to be sufficiently supported to remain stable. In contrast, when the needle is pulled back after the injection is completed, it is desirable that the needle retraction process be subjected to as little resistance as possible.

Accordingly, those skilled in the art are directed to developing a disposable syringe that is easy to assemble, has a stable needle and needle holder at the time of injection, and has low resistance when pulled back after injection.

Summary of the invention

In view of the above-mentioned drawbacks of the prior art, the technical problem to be solved by the present invention is to provide a needle holder that is sufficiently stable during injection, and which can easily pull the needle holder and the needle back to the syringe after the injection is completed. Syringe.

In order to achieve the above object, the present invention provides A disposable syringe comprising a needle holder, a syringe and a core rod, further comprising a support member fixed to the syringe barrel and fixing the needle holder relative to the syringe barrel, the support member and the core rod being configured to: When the rod is pulled back, the core rod acts on the support and disengages the support from the barrel.

In a preferred embodiment of the invention, the support member and the core rod are configured to disengage the support member from the barrel by deforming the support member.

In a preferred embodiment of the invention, the hub and the support are configured to apply a force from the hub to the circumference or end of the support.

In a preferred embodiment of the invention, the core rod and the support member are configured to cause a force from the core rod to act on a central portion of the support member.

In a preferred embodiment of the invention, the support has The circumference or the end, the circumference and the end are located in the corresponding annular groove or mutually independent recess provided inside the barrel.

In a preferred embodiment of the invention, the support member is circular, petal, strip or radial.

In another preferred embodiment of the invention, the support member is a circular sheet.

In another preferred embodiment of the invention, the support member is monolithic, single-slotted or multi-slotted.

In another preferred embodiment of the invention, the central portion of the support member projects toward the needle seat.

In another preferred embodiment of the invention, the support member has a spherical surface, a curved surface, an umbrella surface or a polygonal surface that is convex toward the needle holder.

In another preferred embodiment of the invention, the support member is reversed when the core rod acts on the support member.

In another preferred embodiment of the invention, the hub is in contact with the support only at the periphery or end of the support.

In another preferred embodiment of the invention, the bottom surface of the hub is a tapered surface, a polygonal surface, a spherical surface or a curved surface that is recessed from the outside to the inside.

In another preferred embodiment of the invention, the support member is at least partially thinner than the other portions.

In another preferred embodiment of the invention, at least a portion of the support member has greater elasticity or flexibility than the other portions.

In another preferred embodiment of the present invention, Provided on the head of the core rod is a structure comprising a sheet portion, a neck portion and a blocking portion which are sequentially connected, the sheet portion being deflectable in a direction toward or away from the blocking portion, the diameter of the sheet portion being larger than The diameter of the blocking portion, the diameter of the neck portion is smaller than the diameter of the sheet portion and the blocking portion, and the length of the neck portion, that is, the spacing distance between the sheet portion and the blocking portion is set to be when the sheet portion faces the blocking portion When deflected, the sheet portion may not continue to deflect due to abutment against the circumference of the barrier portion and form a flattened surface, and the sheet portion is free to deflect in a direction away from the blocking portion.

The disposable syringe according to the present invention maintains the balance of the needle seat and the needle at the time of injection by bringing the force receiving position of the support member close to or coincident at the time of injection, and the core rod is pulled back while the needle is pulled back. At this time, the moment is generated by staggering the force-receiving position, so that, like the lever, the support member and the syringe can be disengaged with a small force. The spherical surface, the curved surface or the umbrella surface which is arranged to support the support member on the one hand can improve the supporting force of the support member on the needle seat, and on the other hand, the spherical surface, the curved surface, the polygonal surface or the umbrella surface can be reversed. The force generated when turning over makes the support and the syringe easier to disengage. In addition, the manner in which the circular support and the annular groove cooperate does not require alignment of the two in the circumferential direction, thereby making assembly easier.

The concept, the specific structure and the technical effects of the present invention will be further described in conjunction with the accompanying drawings in order to fully understand the objects, features and effects of the invention.

DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial axial cutaway view of one embodiment of a disposable syringe of the present invention.

Figure 2 is a schematic cross-sectional view of one embodiment of a support member of the present invention.

Figure 3 is a schematic cross-sectional view of another embodiment of the support of the present invention.

Figure 4 is a schematic cross-sectional view of another embodiment of the support of the present invention.

Figure 5 is a schematic cross-sectional view showing another embodiment of the support member of the present invention

Fig. 6 is a perspective view showing the appearance of an embodiment of the pull-back portion of the present invention.

Figure 7 is a perspective view showing another embodiment of the support member of the present invention.

Figure 8 is a schematic cross-sectional view of another embodiment of the support of the present invention.

Figure 9 is a schematic cross-sectional view of another embodiment of the support of the present invention.

detailed description

A preferred embodiment of the present invention is shown in Fig. 1, in which 1 is a hub, 2 is a syringe, 3 is a support, and 4 is a stem of the core.

The support member 3 can have a variety of specific embodiments, such as a disk shape, a petal shape, a strip shape, or a radial shape, thereby correspondingly having a peripheral edge or end portion 31. The support member 3 is preferably made of a material having a certain flexibility such as plastic or the like. The circumference or end 31 of the support member 3 is located in an annular groove or a separate recess 21 provided in the inner side of the barrel 2. The needle hub 1 is sealingly fitted in the syringe 2 by a sealing ring 5, and is constrained by the barrel 2 in the upper part of FIG. 1 (ie, in front of the base), and the lower side (ie, the rear of the base) is supported by the support member 3, thereby It is held between the barrel 2 and the support 3. The hub 1 is configured to be in contact with the support 3 only at or near the periphery or end 31 of the support 3. For example, as shown in Fig. 1, the bottom surface 11 of the hub 1 is arranged to be gradually recessed from the outermost edge thereof toward the center through hole 12 of the hub 1 as a funnel. Thus, the force receiving position of the support member 3 on the needle hub 1 is very close to the force receiving position of the annular groove or the recess 21 on the syringe 1 to the support member 3, and even nearly coincident, so that the needle (not shown) is The pressure applied at the time of injection is directly transmitted to the syringe 2 via the needle hub 1, so that the support member 3 and the needle holder 1 can maintain good stability during the injection process.

The support member 3 has a central through hole 35 on which the pull-back portion 41 is provided. When the injection is made, the core rod is pushed, and the pull-back portion 41 on the head 4 can be pushed through the center through hole 35, but when the core rod is pulled back, the pull-back portion 41 is blocked at the opening of the center through hole 35. Applying a pulling back force to the support member 3. At this time, the support member 3 receives the upward supporting force of the annular groove or the recess 21 at its peripheral edge or end portion 31, and the downward force of the pulled-back portion 41 at its central portion due to the distance between the stressed positions. And the direction of the force is different, so the force acting on the support member 3 forms a moment, and under the action of the moment, the support member 3 is deformed, and starts to move downward from the central portion thereof while driving the periphery or the end portion 31 thereof. It is detached from the annular groove or the recess 21, and due to the existence of the moment, like the lever, the entire detachment process of the above-described support member 3 can be completed with a small force.

Through the above-described arrangement of the support member 3, it is solved that the needle holder 1 is required to remain sufficiently stable at the time of injection, and the needle holder 1 can be easily pulled back to the syringe 2 after the injection is completed.

In order to avoid the additional step of aligning the end 31 with the dimple 21 during assembly, 21 is preferably an annular groove provided inside the barrel 2, such that even if the support 3 is strip or radial with a plurality of ends It is also possible to fit directly into the annular groove 21, so that alignment adjustment at the time of assembly is not required. However, in order to minimize the amount of residual liquid, the support member 3 is also preferably in the form of a disk, and the support member 3 may be a whole piece in order to make the support member 3 more easily pulled out from the annular groove 21 when pulled back. Alternatively, either a single groove is formed in the support member 3, or the support member 3 is provided with a plurality of grooves, so that it is set to be multi-piece as shown in FIG.

In order to better fit the support member 3 and the corresponding annular groove or the mutually independent dimples 21, the circumference or end of the support member 3 may further comprise a mating segment 37 that matches the shape of the groove or dimple 21, The mating segment 37 may also be unequal in thickness with other portions, as shown in Fig. 8, wherein the mating segment 27 is disposed to be relatively thin so that the drag of the support member 3 is less.

Further, the support member 3 may be disposed to be convex toward the hub 1, as shown in Fig. 2, the face 32 of the support member 3 is provided as a spherical surface or a curved surface. This is similar to the principle of an arch bridge on the one hand, such a spherical or curved surface arrangement makes the support of the support 3 to the needle holder 3 more stable during injection; on the other hand, the bottom surface 11 of the needle holder 1 can also be set to The spherical surface or the curved surface smaller than the curvature of the support member 3 causes the bottom surface 11 and the surface 32 of the support member 3 to form a surface contact at the circumferential edge at the time of normal or compression deformation, thereby enhancing the supporting action. Understandably, The bottom surface of the needle seat is set to The same purpose can be achieved by a tapered surface, a polygonal surface, a spherical surface or a curved surface which is recessed from its outer edge toward its central through hole. On the other hand, at the time of pulling back, the peripheral edge or end portion 31 of the support member 3 is more easily detached from the annular groove or the recess 21 due to the inversion of the spherical surface or the curved surface itself. In addition, the arrangement of the upwardly convex spherical or curved surface also makes the process resistance of assembling the support member 3 to the annular groove 21 smaller.

Further, as shown in FIG. 3, the support member 3 may be disposed to be unequal thickness, such as providing the recess 33 thereon, or as shown in FIG. 4, different portions of the support member 3 have different characteristics, such as The connecting portion 34 is provided thereon, and the connecting portion 34 can have better elasticity or flexibility than other portions of the support member 3, so that the support member 3 is more easily turned over when the central portion is stressed.

The support member 3 can also be provided as an umbrella shape 36 which is easier to process as shown in Fig. 5, and the above-described recess 33, the connecting portion 34 or the fitting portion 37 can also be provided thereon to make it easier to flip.

Similarly, the support member 3 can also be provided as a polygonal face as shown in Fig. 9, and the above-described recess 33, the connecting portion 34 or the engaging portion 37 can also be provided thereon to make it easier to flip.

In the embodiment shown in FIG. 1, the inner side of the central through hole 12 of the hub 1 is provided with a shoulder portion 13, and the head 4 is correspondingly provided with another pull-back portion 42, and the pull-back portion 42 and the pull-back portion 41 are spaced apart. A distance. At the time of injection, the pull-back portion 42 is pushed over the shoulder portion 13 inside the center through hole 12, and the pull-back portion 41 is pushed through the center through hole 35; when the injection is completed, the pull-back portion 41 firstly supports the support piece 3 from the ring shape. The groove or the recess 2 is pulled out, at which time the needle holder 1 has lost its support and support for the support piece 3, and then the pull-back portion 42 is engaged with the shoulder portion 13, further pulling the needle holder 1 into the needle. Inside the tube 2.

The retracting

portions

41, 42 can have various embodiments, including a common conical table. When the head is pushed up, the conical table is pushed through the central through hole 35 or the shoulder portion 13 through the tapered surface thereof, and when pulled back, The bottom surface of the conical table is then engaged with the central through hole 35 or the shoulder 13 to apply a downward pulling force to the support or the hub.

The pull-

back portions

41, 42 may also be the structure 6 as shown in FIGS. 1 and 6, which in turn comprises three portions in the longitudinal direction of the head 4: a sheet portion 61, a neck portion 62, and a blocking portion 63, wherein The diameter of the sheet portion 61 is larger than the diameter of the blocking portion 63, the diameter of the neck portion 62 is smaller than the diameters of the sheet portion 61 and the blocking portion 63, and the length thereof is set to be when the sheet portion 61 is bent and deformed toward the blocking portion 62. It is in contact with the periphery of the blocking portion 62. The diameter of the sheet portion 61 is larger than the inner diameter of the center through hole 35 and the shoulder portion 13, and the blocking portion 63 is smaller than the inner diameter of the center through hole 35 and the shoulder portion 13. When the head 4 is pushed up, the sheet portion 61 is deflected downward so that the structure 6 can pass through the center through hole 35 and the shoulder portion 13; and when the head portion 4 is pulled back, the sheet portion 61 is deflected toward the blocking portion 63 Since it is restricted against the circumference of the blocking portion 63, the deflection cannot be continued and a flattened disk-like flat tapered surface is thus formed, so that the sheet portion 61 abuts against the periphery of the blocking portion 63 and the center through hole 35. Or between the shoulders 13, thereby applying a downward pulling force to the support or the hub.

The above has described in detail the preferred embodiments of the invention. It should be understood that many modifications and variations can be made in the present invention without departing from the scope of the invention. Therefore, any technical solution that can be obtained by a person skilled in the art based on the prior art based on the prior art by logic analysis, reasoning or limited experimentation should be within the scope of protection determined by the claims.

Claims

A disposable syringe comprising a needle holder, a syringe and a core rod, further comprising a support member, the support member being fixed to the syringe barrel, and fixing the needle holder to the syringe barrel The support member and the core rod are configured to act on the support member and disengage the support member from the syringe barrel when the core rod is pulled back.
The disposable syringe of claim 1 wherein said support member and said core rod are configured to disengage said support member from said barrel by deforming said support member.
The disposable syringe of claim 1 wherein the hub and the support are configured to apply a force from the hub to a circumference or end of the support.
The disposable syringe of claim 1, wherein the core rod and the support member are configured to cause a force from the core rod to act on a central portion of the support member.
A disposable syringe according to claim 1 wherein said support member has a circumference or end, said peripheral edge and end portion being located in an annular groove or a separate recess provided on the inside of said barrel. In the pit.
The disposable syringe of claim 1 wherein said support member is circular, petal, strip or radial.
The disposable syringe of claim 1 wherein said support member is a circular sheet.
The disposable syringe of claim 1 wherein said support member is monolithic, single-slotted or multi-slotted.
A disposable syringe according to claim 1, wherein said central portion of said support member projects toward said needle holder.
The disposable syringe of claim 1 wherein said support member has a spherical, curved, polygonal or umbrella shaped surface that projects toward said hub.
A disposable syringe according to claim 10, wherein said support member is inverted in reverse when said core rod acts on said support member.
The disposable syringe of claim 1 wherein said hub is in contact with said support only at said periphery or end of said support.
A disposable syringe according to claim 14 wherein the bottom surface of the hub is in surface contact with the support at the periphery or end of the support.
A disposable syringe according to claim 13 wherein the bottom surface of said hub is a tapered face, a polygonal face, a spherical face or a curved face recessed from the outside to the inside.
The disposable syringe of claim 1 wherein at least a portion of said support member is thinner than other portions.
The disposable syringe of claim 1 wherein at least a portion of said support member has greater flexibility or flexibility than other portions.
A disposable syringe according to claim 1, wherein a structure is provided on the head of said core rod, said structure comprising a sheet portion, a neck portion and a blocking portion which are sequentially connected, said sheet portion being Deflected in a direction toward or away from the blocking portion, the diameter of the sheet portion being larger than the diameter of the blocking portion, the diameter of the neck portion being smaller than the diameter of the sheet portion and the blocking portion, and The length of the neck portion, that is, the separation distance between the sheet portion and the blocking portion is set such that when the sheet portion is deflected toward the blocking portion, the sheet portion may abut against the blockage The circumference of the portion cannot continue to deflect and form a flattened surface, and the sheet portion is free to deflect in a direction away from the blocking portion.