JPH08141082A - Injector - Google Patents

Abstract

PURPOSE: To make it possible to set up a hub integrally set up with an injection needle from the tip side of this syringe of an injector housed with the injection needle in the syringe after use of the injector. CONSTITUTION: The front end side of the small-diameter cylindrical part of the syringe 2 to be fitted with the hub 4 is formed in a front split 2f part formed with a slit 2j and a detaining pawl 2g is formed at the front end of this front split part 2f. On the other hand, a stepped part for detaining is formed on the outer peripheral surface of the hub 4 so that the removal of the hub 4 inserted from the front end side to the front end side of the syringe 2 by the elastic deformation of the front split part 2f is prevented by detaining the stepped part for detaining to the detaining pawl 2g.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe mainly used for medical purposes.

[0002]

2. Description of the Related Art In recent years, secondary infection mediated by an injection needle has become a major social problem in syringes used for medical purposes, and therefore disposable syringes are widely used. However, if the injection needle is left exposed when the syringe is discarded, there is a risk that the injection needle may be inadvertently touched and injured, and the secondary infection may occur. In order to avoid this, it has been proposed to store the injection needle in the syringe of the used syringe. By the way, in the syringe storage method, the hub and the plunger are integrated by pushing the engagement protrusion provided on the plunger tip into the engagement recess provided on the hub, and pulling out the plunger from the syringe. In conjunction with this, the hub is housed in the syringe together with the needle. In that case, it is necessary to prevent the hub from coming out of the syringe small-diameter cylinder portion due to the pressure during injection. Therefore, as disclosed in Japanese Patent Laid-Open No. 6-261947, the inner diameter of the tip of the small-diameter tubular portion is made small so that the hub is locked and prevented from being pulled out. However, with this product, the hub cannot be inserted and installed from the tip of the small diameter cylinder, and it must be inserted and installed from the side of the large diameter cylinder with a long cylinder length. This is difficult and requires assembly in a factory before shipment.

On the other hand, doctors and nurses often select an injection needle depending on the site to be injected and the type of drug solution. In addition to having to prepare multiple types of syringes with built-in, inventory management becomes complicated, and
There is also a problem that extra stock space is required in hospitals.

In order to prevent the hub inserted and assembled from the tip of the small-diameter tubular portion to be pulled out, it is proposed that a retaining member be tightly attached to the outer circumference of the small-diameter tubular portion by screwing or the like. A separate stop member is required, increasing the number of parts,
There is a problem of increased costs.

[0005]

DISCLOSURE OF THE INVENTION The present invention was devised with the object of providing a syringe capable of eliminating these drawbacks in view of the above-mentioned circumstances, and a tubular syringe, It consists of a plunger that can be inserted into and retracted from the syringe, and a hub into which a needle is integrally incorporated and inserted into a small-diameter cylindrical portion formed at the tip of the syringe, and an engaging protrusion provided at the tip of the plunger. In a syringe configured such that the hub and the plunger are integrated by pushing and fitting into the engaging recess provided in the hub, and the hub is housed in the syringe together with the needle in association with pulling out the plunger from the syringe. In forming the hub so that it can be inserted from the distal end side of the syringe small-diameter tubular portion, a small-diameter locking step portion is provided on the outer peripheral surface of the hub, while It engaged with the step portion and is characterized in the provision of the locking claw to the retainer to the distal end side of the hub.

According to the present invention, with this construction, the injection needle can be housed in the syringe, but the injection needle can be removably attached to the syringe without increasing the number of parts. Is.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a syringe, and a syringe 2 into which the liquid medicine of the syringe 1 is injected is integrally formed in a tubular shape with a thermoplastic resin material such as polypropylene, and has a large diameter into which the liquid medicine is injected. A tubular portion 2a and a small-diameter tubular portion 2b that is formed on the tip side of the tubular portion 2a via an inclined tubular portion 2c are concentrically formed. A support piece 2d for supporting a finger when the syringe 1 is used is formed on the proximal end side of the large-diameter cylindrical portion 2a so as to project in a flange shape in the outer diameter direction. On the inner peripheral surface of the end side, a ridge 2e projecting toward the axis is formed in a ring shape. Further, a hub 4 into which an injection needle 3 is integrally incorporated is inserted and incorporated into the small-diameter tubular portion 2b from the tip side of the small-diameter tubular portion 2b, as will be described later.

That is, the slit 2j is formed in the tip portion of the small-diameter cylindrical portion 2b so as to have a predetermined width in the circumferential direction, and is divided into a plurality of portions (in this embodiment, there are four portions with a certain interval). The front crack portion 2f is formed, and the locking claw 2g protruding toward the shaft center is formed on the inner peripheral surface of the front end portion of the front crack portion 2f. Tapered insertion guide surface 2h that gradually protrudes toward the inner diameter side toward the base end side
Are formed. Furthermore, the tip crack portion 2f of the small-diameter cylindrical portion 2b
An arcuate ridge 2i protruding in the axial direction is formed in a ring shape on the base end side.

On the other hand, the hub 4, which is inserted and incorporated into the small-diameter cylindrical portion 2b from the tip side, is formed by using a thermoplastic resin material such as polyethylene, and the injection needle 3 is formed in the axial core portion thereof. An insertion hole 4a for inserting and supporting is formed so as to penetrate from the base end to the tip. Furthermore, hub 4
Includes a large diameter portion 4b having a base end side portion having an outer diameter substantially the same as the inner diameter of the small diameter cylindrical portion 2b, and a small diameter portion 4 having a tip end side portion having a smaller diameter than that.
c and a locking step portion 4d formed between the both diameter portions 4b and 4c. The hub 4 is attached to the small-diameter cylindrical portion 2b at the base end, that is, the large-diameter portion 4b.
Is pressed against the distal end side of the small diameter cylindrical portion 2b, the outer peripheral edge portion of the hub large diameter portion 4b on the proximal end side is pressed and guided by the insertion guide surface 2h of the engaging claw 2g. As a result, the cracked portion 2f is elastically deformed and spreads to the outer diameter side, and the hub 4 is smoothly inserted into the small diameter cylindrical portion 2b until the engaging claw 2g engages with the locking step portion 4d. Hub 4
It is set so that the hub 4 can be mounted in a state in which it is prevented from being pulled out to the tip side by setting by pushing. Moreover, when the hub 4 is attached and set, a concave groove 4e is formed in a substantially V shape on the outer peripheral surface of the hub large diameter portion 4b on the base end side.
The ridges 2 formed on the inner peripheral surface of the small-diameter cylindrical portion 2b at both groove ends.
i is set so as to fit with each other, so that the water tightness between the hub 4 and the syringe 2 is ensured. Here, since the concave groove 4e has a V-groove shape, two watertight contact portions are formed between the concave groove 4e and the ridge 2i, but the hub 4 is force-fitted into the syringe 2 as described later. In this case, the inclined side of the concave groove 4e guides the protrusion 2i to come out of the concave groove 4e.
In this case, the fitting force between the concave groove 4e and the ridge 2i is maintained in the fitted state under the load generated when the injection liquid is injected into the syringe 2, but when the force is inserted into the syringe 2 by force. Is set so that the engagement state is released upon receiving the exit guide.

On the other hand, an insertion hole 4a formed in the hub 4
The base end portion of is formed into a dovetail groove shape in which the hole end portion has a small diameter and the hole back side has a large diameter, and the engaging projection 5d described later is set to be inserted by force fitting. The inner part is formed by a through hole 4f penetrating the large diameter part 4b in the radial direction,
This forms a dovetail-shaped engaging recess 4g.

On the other hand, reference numeral 5 denotes a plunger which is inserted into and retractable from the syringe 2, and the plunger 5 is made of a thermoplastic resin material such as polyethylene and has a cross-shaped supporting shaft portion 5a. And the large-diameter cylindrical portion 2 of the syringe 2.
a It is integrally formed with a disc portion 5b integrally formed on the tip portion of the support shaft portion 5a with a diameter substantially the same as the inner diameter. Further, the tip side surface of the disc portion 5b ensures water tightness with the syringe 2. To prevent the damper 6 from coming off, a damper removal preventing portion 5c is provided in a protruding manner, and further, an engagement protrusion 5d is provided in the tip end side of the damper removal preventing portion 5c. When the plunger 5 is further pushed in after the injection is completed and the damper 6 is in contact with the inclined cylindrical portion 2c, the engaging projection 5d is elastically deformed and the engaging projection 5d is formed on the hub 4 in the engaging recess 4g. And the plunger 5 and the hub 4 are integrated by forcefully fitting
By pulling back the plunger 5 strongly in this state,
The hub 4 is set to be force-fitted into the syringe 2 so that the injection needle 3 is housed in the syringe 2. here,
The tip end surface portion of the damper 6 is an inclined surface that is gentler than the inclination of the syringe inclined cylindrical portion 2c. Then, at the end of injection, as shown in FIG. 2, the outer peripheral edge portion of the damper 6 before the engaging projection 5d is forcibly fitted into the engaging recess 4g is inclined cylinder portion 2c.
It is set so that it can be judged by abutting against the elastically. Incidentally, a notch 4h for communicating the inner part of the hole and the syringe 2 is formed at the hole end of the engaging recess 4g formed in the hub 4. Further, the spindle 5a of the plunger 5
Includes a notch 5e at a position exposed from the syringe 2 when the injection needle 3 is pulled out to a state of being housed in the syringe 2.
After the injection needle 3 is housed in the syringe 2, the plunger 5 can be bent at the cutout 5e. Further, 5f is a flange-shaped pressing piece integrally formed with the base end portion of the support shaft 5a.

Reference numeral 7 denotes a cap which is integrally formed of a thermoplastic resin such as polypropylene and which is detachably attached to the outer peripheral portion of the hub 4 to cover the injection needle 3 and has a large diameter. A locking projection 7b is formed on the inner peripheral surface of the base end 7a. On the other hand, on the outer peripheral surface of the hub small diameter portion 4c,
The rib 4j in which the locking recess 4i is formed is the slit 2
is formed corresponding to j, and the cap 7 is
The locking protrusion 7b is attached to the hub 4 by being attached to a position where it abuts the locking recess 4i, but the hub 4 is inserted and attached to the syringe 2 in this attached state, and the insertion load in that case The movement of the hub 4 to the back side of the cap 7 by
The locking projection 7b is configured to be restricted by locking in the locking recess 4i. Incidentally, the hub 4 is prevented from being pulled out from the cap 7 by light press-fitting of the locking projection 7b into the locking recess 4i. Also,
Between the hub large diameter portion 4b and the cap base end portion 7a,
A space S for inserting the small-diameter cylindrical portion 2b of the syringe is secured.

In the embodiment of the present invention constructed as described above, in the syringe 1, after the injection is completed, the plunger 5 and the hub 4 are integrated and the injection needle 3 is inserted in the syringe 2, as described above.
When the hub 4 in which the injection needle 3 is integrally incorporated for injection is incorporated into the syringe 2, the hub 4 is inserted and incorporated not from the proximal end side of the syringe 2 but from the distal end side thereof. However, the insertion integration is
The hub large diameter portion 4b is pushed in from the tip end side of the syringe small diameter cylinder portion 2b. In this way, the retaining of the hub 4 inserted and incorporated from the tip end side to the tip end side is performed by the locking step portion 4d of the locking claw 2g. Made by locking to. Therefore, the assembling operation of the hub 4 is simplified, and it is not necessary to separately provide a dedicated retaining member for retaining the hub 4 as in the conventional case. As a result, the hub 4 is inserted and attached from the tip side. As a result, a doctor or the like can freely select the injection needle 3 and easily assemble it, but the number of parts can be minimized without the need for a dedicated retaining member.

Further, the insertion work of the hub 4 is promoted by being guided by the tapered insertion id surface 2h formed at the tip of the tip crack portion 4f, and can be smoothly carried out even with a small force. Moreover, in this device, the hub 4 is assembled to the syringe 2 while the cap 7 is still attached, but in this case, in the hub 4, the locking projection 7b contacts the locking recess 4g. Since the contact is regulated to move to the back side of the cap, the hub 4 may move to the back side of the cap due to the load when the hub is assembled, and the injection needle 3 may pop out from the tip side of the cap 7. Absent.

Further, in this structure, a dovetail-shaped engaging concave portion 4g is formed in the hub 4 formed by molding, and the inner diameter of the engaging concave portion 4g has a large hub. Diameter part 4
Since it is formed by the through hole 4f penetrating through b in the radial direction, it is not necessary to make the mold for forming the inner part of the hole into a reverse taper state. Therefore, when the mold is removed, the engaging recess is formed. There is no possibility that the hole end portion of 4g will spread and the retaining engagement function with the engagement protrusion 5d will be impaired, and it will be reliable. Further, in this structure, a notch 4h for communicating the inner part of the hole with the syringe 2 is provided at the hole end of the engaging recess 4g.
Therefore, when the engaging protrusion 5d is forcedly fitted into the engaging recess 4g for fitting, the engaging protrusion 5d closes the insertion hole 4a communicating with the inner side of the engaging recess 4g. It is convenient that the residual injection liquid accumulated in the engaging recess 4g is released to the syringe 2 side when it deeply enters the engaging recess 4g, so that the engaging projection 5d can be easily fitted.

Of course, the present invention is not limited to the above-mentioned embodiment, and as the hub, as in the second embodiment shown in FIG. 10, the hub small-diameter portion 4c has no rib. can do. That is, in the first embodiment, since the rib 4j provided on the hub small diameter portion 4c is for supporting the cap 7, this function can be given only to the cap 7 side. That is,
A hub 4 having a locking rib portion 7c for locking at a locking step portion 4d between the small diameter portion 4c and the large diameter portion 4b of the hub 4, or the hub small diameter portion 4c as in the third embodiment shown in FIG. The locking step portion 7d that locks on the front end surface of the above may be formed. And by doing in this way, it can avoid that a metal mold | die becomes reverse taper at the time of mold formation of a cap. Further, in the third embodiment, it is not necessary to assemble the hub by avoiding the ribs, and the hub mounting operation is further simplified. Further, this means that the slit formed in the syringe small-diameter cylinder portion 2b does not require a gap to avoid the rib as in the first and second embodiments, and the fourth embodiment shown in FIG. As shown in the example, a cut of about 2k is sufficient. Further, as the slit, it is sufficient that the syringe small-diameter cylinder portion expands when the hub is forcibly fitted. Therefore, the number, size, etc. can be appropriately set as necessary. Of course, it is not limited to.

[0017]

In summary, since the present invention is constructed as described above, the syringe after use is retracted into the syringe with the hub integrated with the plunger, and the injection needle is stored in the syringe. Even though it is a configuration that can be done, it can be inserted and installed by pushing the hub with the needle integrated into it from the syringe tip side.In this case, the locking claw of the syringe small diameter cylinder part locks the hub. By locking to the stepped portion, the hub is prevented from coming off from the tip side. Therefore, the operation of assembling the hub into the syringe is simplified, and it is no longer necessary to use a separate retaining member to prevent the hub from being detached, which results in the minimum number of parts. However, the injection needle can be freely selected, and inventory management becomes easy.

[Brief description of drawings]

1 is a cross-sectional view of a syringe.

FIG. 2 is a cross-sectional view of the syringe showing a state before forcibly fitting the engagement protrusion into the engagement recess.

FIG. 3 is a cross-sectional view of the syringe showing a fitted state of the engagement protrusion with the engagement recess.

FIG. 4 is a cross-sectional view of the syringe showing a state where the hub is housed in the syringe.

FIG. 5 is a partial cross-sectional view of the syringe showing a hub in an assembled state.

FIG. 6 is a perspective view of a syringe.

FIG. 7 is a perspective view of a hub.

FIG. 8 is a side view of the hub.

FIG. 9 is a partial cross-sectional view of the syringe showing a mounted state of the cap.

FIG. 10 is a partial cross-sectional view of the syringe showing a cap mounted state of the second embodiment.

FIG. 11 is a partial cross-sectional view of the syringe showing a cap attached state of the third embodiment.

FIG. 12 is a perspective view showing a syringe of a fourth embodiment.

[Explanation of symbols]

 1 Syringe 2 Syringe 2a Large diameter cylinder 2b Small diameter cylinder 2g Locking claw 3 Injection needle 4 Hub 4a Insertion hole 4d Locking step 4f Through hole 4g Engagement recess 4j Rib 5 Plunger 5d Engagement protrusion 6 Damper 7 Cap

Claims (12)

[Claims] 1. A cylindrical syringe, a plunger that is inserted into and retracted from the syringe, a needle that is integrally incorporated, and a hub that is inserted and incorporated into a small-diameter cylindrical portion formed at the tip of the syringe. The hub and the plunger are integrated by pushing the engagement projection provided on the tip of the plunger into the engagement recess provided on the hub, and the hub is integrated with the needle in the syringe in conjunction with pulling the plunger out of the syringe. In the syringe configured to be housed in the above, when the hub is configured to be inserted from the distal end side of the syringe small-diameter tubular portion, a small-diameter locking step portion is provided on the hub outer peripheral surface while The syringe is provided with a locking claw that locks the locking step to prevent the hub from being pulled out toward the distal end side. 2. The syringe according to claim 1, wherein the tip of the small-diameter cylindrical portion has a plurality of cracked portions formed by slits, and locking claws are formed at the cracked portions. Syringe to do. 3. The hub according to claim 1 or 2, wherein a recess groove is formed on the outer peripheral surface of the hub at a position closer to the base end side than the locking claw, and the locking claw is locked on the inner peripheral surface of the syringe small diameter cylindrical portion. A syringe characterized in that a ridge that fits into the groove is formed at a position where the syringe is locked. 4. The fitting force between the concave groove and the ridge according to claim 3, wherein the fitting state is maintained by the force when the plunger is pulled out to inject the injection liquid into the syringe, but the fitting force is integrated with the plunger. The syringe is characterized in that the engagement state is set to be released when the plunger is pulled out in the locked state. 5. The syringe according to claim 4, wherein the concave groove has a triangular groove shape, and the convex stripe has an arc shape that abuts both ends of the triangular groove. 6. The syringe according to claim 1, 2 or 3, wherein an insertion guide surface for guiding the insertion of the hub is formed in a tapered shape at the tip of the small-diameter cylinder portion of the syringe. 7. The hub according to claim 1, wherein a cap base end portion for covering the needle is detachably attached to the hub, and the cap base end portion is provided between the inner peripheral surface and the hub outer peripheral surface. The syringe is characterized in that there is provided a space into which the tip portion of the small-diameter cylinder portion of the syringe can be inserted in order to lock the locking claw to the locking step portion. 8. The cap according to claim 7, wherein a locking projection is formed on the cap to restrict the hub from sinking into the cap when the hub is locked and the locking claw is locked to the locking step. Syringe characterized by being. 9. The syringe according to claim 1, wherein the inner hole of the engaging recess provided in the hub is formed by a through hole that penetrates the hub in a radial direction. 10. The syringe according to claim 1, wherein a notch for communicating with the inner part of the hole is formed at the hole end of the engaging recess provided in the hub. 11. The syringe according to claim 2, wherein the slit has a predetermined width in the circumferential direction. 12. The syringe according to claim 2, wherein the slit is a notch.