JP2792339B2 - Anti-reuse syringe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a syringe for preventing reuse.

[0002]

2. Description of the Related Art In a syringe, a plunger is slidably inserted in an axial direction through a proximal end opening of an outer cylinder having an injection needle. By the way, if a syringe is reused, there is a risk of infection. Therefore, the syringe is disposable. However, if the syringe is discarded as it is, it may be reused and an infection accident may occur. Therefore, in the related art, after using the syringe, most of the plunger is pulled out of the outer cylinder, and the plunger is folded or bent to prevent the syringe from being reused. However, conventionally, the plunger has been integrally formed of a synthetic resin.

[0003]

For this reason, in the prior art described above, the strength of the plunger is so large that the plunger cannot be easily folded or bent as described above, and therefore, the operation is easy. Accordingly, there has been a demand for a proposal that can prevent reuse of the syringe. The purpose of the present invention is
An object of the present invention is to provide a reusable syringe which can solve the above problems and can prevent the reusable syringe by easy operation.

[0004]

In order to solve the above-mentioned problems, a feature of the present invention is that a plunger is slidably inserted in the axial direction from the base end opening of the outer cylinder. In the syringe, a small-diameter portion having an inner diameter smaller than other portions is formed on the inner peripheral surface of the proximal end portion of the outer cylinder, and the plunger forms a base-side divided body constituting the base side and a distal end side. The engaging portion is formed at the distal end of the base-side divided body, and at the base of the distal-side divided body,
A stopper is formed to abut the small diameter portion to prevent the plunger from sliding rearward.
The point is that an engaged portion that is engaged with the engaging portion from the radial direction and that connects and fixes the base-side split body and the distal-end-side split body is formed.

[0005]

After the syringe has been used once, the plunger is divided into two parts. As a result, the engaging portion of the divided body is deformed, so that re-engagement becomes impossible, and reuse of the syringe is prevented.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 show a syringe,
As shown in other drawings, the syringe includes an outer cylinder 1, a plunger 2, and an injection needle 3. Outer cylinder 1
Is formed integrally with a relatively hard synthetic resin, for example, polypropylene, and is made transparent, translucent, or opaque. As shown in FIGS. Having. The main body 5 has a cylindrical shape with a constant diameter, a closed end, and an injection needle 3 at the front end. The main body 5 is open at the base end, and a small-diameter portion 7 whose inner diameter is smaller than other parts is formed on the inner peripheral surface of the base end of the main body 5. A flange 6 projects radially outward from the base end of the main body 5.

The plunger 2 is made of a relatively hard synthetic resin,
For example, it is formed of polypropylene and is transparent, translucent, or opaque. The plunger 2 is removably inserted into the main body 5 from the base end opening thereof and is slidable in the axial direction inside the main body 5. FIG.
As shown in FIG.
The plunger 2 is divided into individual parts, and includes a base-side divided body 9 that forms substantially the entire part except for the distal end, and a distal-part divided body 10 that constitutes the distal end of the plunger 2. Have been.

The base-side divided body 9 is formed by integrally forming four blades 12 and a push portion 13. The four blades 12 mainly constitute the base-side divided body 9 and are equally arranged in the circumferential direction.
The blades 12 extend in the radial direction from the axis of the base-side divided body 9 and are integrated at the axis. At the tip portions of the pair of blades 12 at the radially symmetrical portions, a wide portion 14 formed wider than the other portion is formed over the entire length in the radial direction, and the wide portion 14 has an axial direction. A substantially T-shaped dovetail-type engaging portion 15 which opens forward and in the radial direction is formed over the entire length in the radial direction. In the specification, the front side indicates the tip side of the injection needle 3, and the rear side indicates the opposite side. The pressing portion 13 includes four blades 12.
Are connected.

The tip end side divided body 10 includes a stopper 17 and
It has a projection 18 and a gasket 19. Stopper 17
, Which constitutes a base portion of the distal-end-side divided body 10, is formed in a disk shape, and abuts on the small-diameter portion 7 of the main body 5 to prevent the plunger 2 from being accidentally detached from the outer cylinder 1. A T-shaped dovetail type engaged portion 20 protruding rearward is formed on the proximal end surface of the stopper 17 over the entire length in the radial direction, and the engaged portion 20 is engaged with the base-side divided body 9. Joint 1
5, the two divided bodies are engaged by being inserted and engaged in the radial direction. At the time of the insertion, the wide portion 14 is elastically deformed, the engaging portion 14 and the engaged portion 20 are pressed, and the base-side split body 9 and the distal-end-side split body 10 are securely connected and fixed. The protruding portion 18 protrudes forward from the stopper 17 in the axial center direction, and a gasket 19 is fitted on the protruding portion 18 so as to be detachable.
It faces the stopper 17 with a small gap in the axial direction.

According to the embodiment configured as described above, after the base-side divided body 9 and the distal-end-side divided body 10 are engaged to form the plunger 2, the plunger 2 is inserted into the outer cylinder 1. Thus, a syringe is configured. As a result, the syringe can be used in the same manner as before, but after the syringe is used once, reuse of the syringe is prevented as follows. That is, first, most of the plunger 2 is pulled out as shown in FIG. 4, and the stopper 17 of the plunger 2 is brought into contact with the distal end of the small diameter portion 7 of the outer cylinder 1.

Next, a force is applied to the base-side divided body 9 so as to squeeze the engaging portion 15 against the engaged portion 20, and as shown in FIG. The engagement of 20 is released, and the base-side split body 9 is separated from the distal-end-side split body 10. At this time, since the engaging portion 15 and the engaged portion 20 are deformed and the engaging portion 15 and the engaged portion 20 cannot be engaged again, the reuse of the syringe is prevented. The engaging strength between the engaging portion 15 and the engaged portion 20 is such that the plunger 2 does not separate when the plunger 2 is slid with respect to the outer cylinder 1 in the axial direction. Only when separated, the engaging portion 15 and the engaged portion 20 are deformed and separated.

FIGS. 6 to 8 show a comparative example of the present invention, in which a dovetail-type engaging member is provided on the inner side of the tip of a pair of blades 12 at the radially symmetrical portion of the base-side divided body 9. Joint 15
Are formed, and the inner portion of the engaging portion 15 of the pair of blades 12 and a portion following the axial center rear portion thereof,
A notch 22 is formed. In addition, the tip side divided body 10
From the base end face of the stopper 17 are arranged evenly in the circumferential direction.
Each of the protrusions 23 is provided to protrude rearward in the axial direction, and is in contact with the blade 12 of the base-side divided body 9 in the axial direction. The projecting portion 23 extends in the radial direction from the axis of the tip end side divided body 10 and is integrated with the axis. A trapezoidal dovetail-shaped engaged portion 20 is formed on the pair of projections 23 at the engagement direction symmetrical portions.
, The engaging portion 15 is engaged. At the time of the engagement, both sides of the engagement portion 15 are elastically deformed toward the notch portion 23,
In the engaged state, the engaging portion 15 and the engaged portion 20 are pressed against each other in the radial direction, and the base-side split body 9 is securely connected and fixed to the distal-end-side split body 10.

[0013]

As described in detail above, according to the present invention,
The following effects are obtained. After using the syringe, pull out the plunger, abut its stopper against the small-diameter portion of the outer cylinder, and apply a force to pry the base-side divided body against the distal-side divided body, The base-side divided body can be separated from the distal-side divided body, and reuse of the syringe can be prevented. Since the engaged portion of the distal-side split body is engaged with the engaging portion of the base-side split body from the radial direction of the plunger without engaging with the engaged portion of the plunger in the axial direction, the two split bodies are firmly engaged. Even when the syringe is not used, when the syringe is used, the plunger is pulled out to draw the chemical solution into the outer cylinder, and when an external force is applied to separate the engaging portion and the engaged portion in the axial direction, the engaging portion is disengaged. There is no fear that the engagement between the and the engaged portion is accidentally released. By the engagement of the engagement portion and the engaged portion, the base side divided body and the distal end side divided body are connected and fixed, and when the plunger is operated,
Since there was no useless movement such that both divided bodies relatively moved in the axial direction, when using the syringe,
The amount of operation of the plunger can be the same as in the past. Since the coupling fixed portion of the plunger and the separated portion after use are the same, the structure of the plunger can be simplified. Since no protrusion or the like over which the plunger gets over is formed in the distal end side of the outer cylinder, a large force is not required for pushing the plunger at the time of injection, and the plunger can be easily operated. There is no danger that the syringe will become unusable after getting over the projection or the like.

[Brief description of the drawings]

FIG. 1 is a partially sectional front view of a syringe showing one embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a front sectional view showing a state where most of the plunger of FIG. 1 is pulled out.

FIG. 5 is a perspective view showing a state in which the base side divided body and the distal end side divided body of FIG. 2 are separated.

FIG. 6 is a front sectional view of a main part showing a comparative example of the present invention.

FIG. 7 is a perspective view of the main part.

FIG. 8 is a sectional view taken along line BB of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 Plunger 3 Injection needle 9 Base-side split body 10 Tip-side split body 15 Engagement part 20 Engagement part

Claims (1)

(57) [Claims] 1. A syringe in which a plunger is slidably inserted in an axial direction from an opening at a base end thereof into an outer cylinder. A small-diameter portion having a small diameter is formed, and the plunger is constituted by a base-side divided body constituting the base side and a distal-side divided body constituting the distal end side, and is engaged with the distal end of the base-side divided body. A stopper is formed at the base of the divided body at the distal end side, and a stopper is formed to abut against the small-diameter portion to prevent sliding of the plunger rearward. Engage with the base end of the stopper from the radial direction. A reuse prevention syringe, wherein an engaged portion is formed to be engaged with the portion to connect and fix the base-side divided body and the distal-end-side divided body.