JPH09225029A - Injector and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable previous mounting of an injection needle at an injection port without disturbing high pressure steam sterilization and filling of an injection agent into an outer cylinder with neary no mixed air by arranging the outer cylinder as a thermoplastic resin molded product with the inner diameter of a gasket insertion opening part larger than the inner diameter of a sliding part of the gasket. SOLUTION: An insertion opening part 2C of a gasket 4 of an outer cylinder 2 has its inner diameter L larger than the inner diameter M of a sliding part 2B of the gasket 4. More concretely, the insertion opening part 2C of the gasket 4 is a thermoplastic resin molded product which is formed by expanding gradually. Gradually tapered expansion is not necessary as the shape of the opening part 2C. It suffices that air in the outer cylinder 2 can escape from a gap between the gasket 4 and the inner wall of the outer cylinder 2 when the injection agent 6 is housed and sealed by the gasket 4. A plug body 5 is arranged at a sliding part 2B of the outer cylinder 2 spaced at an interval from an injection port 2A avoiding a ridge rib 11 and the injection agent 6 undergoes a steam sterilization to be housed into the outer cylinder 5 between the gasket 4 and the plug body 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe pre-filled with an injection agent, and more specifically, it is suitable for high-pressure steam sterilization in which air is hardly mixed when the injection agent is filled into the outer cylinder. The present invention relates to a syringe that does not cause any trouble and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, in order to prevent medical accidents and to prevent hospital-acquired infections and the like as much as possible, sterile or aseptic pre-filled syringes have been filled with injections such as drugs or medicinal solutions. Syringes, commonly referred to as field syringes, have been proposed. In addition, a multi-component syringe in which an injection of two or more pharmaceutical ingredients is separately filled in the prefield syringe until the injection is also proposed.

Conventionally, a syringe has a sealing cap attached to the injection port of an outer cylinder, a gasket of a plunger is inserted from a base end insertion opening of the outer cylinder, and an injectable agent is contained in the gasket. . And when filling the injection into the outer cylinder, first the gasket is inserted into the outer cylinder to a predetermined position, then the injection is filled from the injection port of the outer cylinder, and after the filling, the sealing cap is opened. Be attached to. In this state, the syringe is subjected to autoclaving. In this case, since the injection is filled from the injection port of the outer cylinder, the injection can be filled with almost no air in the outer cylinder.

[0004]

However, in the conventional syringe, since the injection port of the outer cylinder is provided with the sealing cap, the injection needle cannot be attached to the injection port in advance. Therefore, when the syringe is used, it is necessary to attach the injection needle in the hospital, which may cause hospital infection. In addition, in a two-component syringe or the like, since the injection liquid is filled between the gasket and the plug body, the injection liquid is filled from the insertion opening of the gasket, but there is a disadvantage that air or the like remains in the outer cylinder, When high-pressure steam sterilization of a syringe is performed in such a state where air remains, there is a problem that a pressure difference is caused by air in the outer cylinder and the outer cylinder of the thermoplastic resin is deformed.

Therefore, an object of the present invention is to prevent air from being mixed in the outer cylinder when it is filled with an injectable agent, which does not hinder high-pressure steam sterilization, and in which an injection needle is previously attached to the injection port. An object of the present invention is to provide a syringe and a manufacturing method thereof.

[0006]

SUMMARY OF THE INVENTION The present invention provides a syringe in which an injection agent is previously housed in an outer cylinder, wherein the outer cylinder has an inner diameter (L) of a gasket insertion opening part of a sliding part of the gasket. The above object is achieved by providing a syringe characterized by being a thermoplastic resin molded product having a diameter larger than the inner diameter (M). The present invention also provides the above-mentioned syringe, wherein the injection is filled from the insertion opening of the gasket into the outer cylinder and a liquid level higher than a position where the inner diameter (L) of the insertion opening is formed, ,
A method for manufacturing a syringe, characterized in that the gasket is inserted from above the opening to liquid-tightly fill the outer cylinder with the injection agent, and then the injection agent is sterilized by high-pressure steam with the outer tube. By doing so, the above object is achieved.

[0007]

In the outer cylinder of the above syringe, for example, when the outer cylinder is filled with the injection agent in the state shown in FIG. 3 and the gasket is inserted from above, the air in the outer cylinder spreads toward the end as shown in FIG. If it is possible to escape from the side wall of the opening of the injection, and the liquid level is a little higher than the starting position of the end spread, the injection is liquid-tightly filled in the outer cylinder with a slight amount protruding from the gasket, As a result, most of the air is removed from the inside of the outer cylinder. Moreover, in the method of filling the injection through the insertion opening of such a gasket, it is not necessary to provide a sealing cap at the injection port as shown in FIG. An injection needle can be attached to the outlet or the like in advance.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a syringe according to the present invention will be described below in detail with reference to the accompanying drawings. 1 is a side sectional view of a first embodiment of the syringe of the present invention, FIG. 2 is a sectional view of the syringe taken along the line I-I of FIG. 1, and FIGS. 3A and 3B are of the syringe of FIG. FIG. 4 is a side sectional view during assembly, FIG. 4 is a side sectional view during assembly of the syringe of FIG. 1, and FIGS. 5 and 6 are side sectional views during use of the syringe in the first embodiment.

The syringe 1 of the first embodiment shown in FIGS.
Is a syringe in which an injection agent is stored in advance in the outer cylinder, and in the outer cylinder 2, the inner diameter (L) of the insertion opening 2C of the gasket 4 is larger than the inner diameter (M) of the sliding portion 2B of the gasket 4. It is a thermoplastic resin molded product formed in. That is, the insertion opening 2C of the gasket 4 of this embodiment is formed so as to widen toward the end.

To further explain the syringe 1 of this embodiment, the outer cylinder 2 of the syringe 1 of this embodiment is a molded product of a thermoplastic resin and is formed by injection molding. Since the injection needle 7 is set in the outer cylinder 2 in advance, the plug body 5 is arranged in the inner portion of the outer cylinder 2, and the convex rib 11 to be described later is formed to give the plug body 5 an opening function. There is. As the thermoplastic resin molded product,
For example, low density or high density polyethylene, polypropylene, polyolefins such as polybutadiene-1, polyvinyl chloride, polyvinylidene chloride, vinylidene chloride copolymer, polymethyl methacrylate, polyvinyl alcohol,
Examples thereof include ethylene-vinyl alcohol copolymer, acrylonitrile copolymer, and polyethylene terephthalate. In particular, polyolefins are preferable from the viewpoint of versatility and chemicals, and those having a high glass transition temperature such as an amorphous cyclic olefin copolymer and a specific gravity of 1.0 to 1.1 are desirable. . Specifically, the brand name ZEONEX (Nippon Zeon Co., Ltd.), which is recently used as a material for optical disc substrates, optical lenses, etc.,
A polyolefin resin such as the trademark Apel (Mitsui Petrochemical Industry Co., Ltd.).

The plug 5 is provided on the gasket 4 side with a certain distance from the injection port 2A, and the inner wall of the outer cylinder 2 portion between the plug 5 and the injection port 2A has an axial direction of the outer cylinder 2. The ribs 11, 11 ...
When reaching A, the outer peripheral wall of the plug body 5 is elastically deformed by the convex ribs 11, 11 ... And a void is formed in which the injection 6 flows into the injection port 2A. The gasket 4 and the plug 5 may be any as long as they have an elastic body that maintains liquid tightness with the inner wall of the outer cylinder 2. Specifically, a rubber gasket and a rubber stopper are used.

A plurality of convex ribs 11 on the inner wall surface of the outer cylinder 2 between the plug body 5 and the injection port 2A are formed in the axial direction of the outer cylinder 2. That is, the ribs 11 are formed in a direction substantially the same as the die cutting direction when the outer cylinder 2 is molded.
The number of the ribs 11 is 1 or more, preferably 3 or more, and more preferably 5 or more. When a plurality of convex ribs 11 are formed, they may be arranged symmetrically with respect to each other, or may be formed so as to be biased to a part of the inner wall surface of the outer cylinder. Further, the convex rib 11 is a tapered top portion 11A that gradually rises toward the inner end of the outer cylinder 2. The taper is not always necessary. However, such taper top 11
The formation of A is not affected by the mold or the like when the mold is removed.
The mold can be smoothly removed, and the plug 5 can be smoothly inserted deep into the outer cylinder 2 when the syringe 1 is used.

As shown in FIG. 2, in this embodiment, the maximum height (w) of the convex rib tops 11A of the outer cylinder 2 is 1 mm. The maximum height (w) of the convex rib top 11A is the inner diameter (M) of the outer cylinder.
The preferred range is determined by the convex rib top 11A.
Maximum height (w) is 1/50 to 1 / of the inner diameter (M) of the outer cylinder
Preferably it is 5 times. If the maximum height (w) of the convex rib top portion 11A is less than the above range, there is a possibility that a sufficient gap 12 may not be formed between the outer peripheral wall of the outer cylinder 2 and the inner peripheral wall of the plug body 5, and the maximum height (w) exceeds the above range. Then, the slidability of the plug body 5 deteriorates. Further, a plurality of protrusions 14 are formed on the inner wall of the shoulder portion 13 in which the injection port 2A of the outer cylinder 2 of the present embodiment is formed, and the protrusions 14 allow the inner wall of the outer cylinder 2 and the plug 5 to be separated. A passage is formed between the protrusions 14 for guiding the injection 6 flowing through the space 12 between the outer peripheral wall and the injection port 2A. Although such a passage is not always necessary, the stopper 5 is prevented from completely adhering to the inner peripheral surface of the shoulder portion 13 and blocking the outflow passage of the injection 6. Therefore, instead of forming the protrusion 14, the shoulder 13
A groove portion may be formed on the inner wall surface of the to secure a passage to the injection port 2A.

Insertion opening 2C of the gasket 4 of the outer cylinder 2
Has an inner diameter (L) larger than the inner diameter (M) of the sliding portion 2B of the gasket 4. In this embodiment, specifically, the insertion opening 2C of the gasket 4 is formed so as to widen toward the end. The shape of the opening 2C does not need to be a tapered divergent shape, and when the injection agent 6 is hermetically stored in the gasket 4, the air in the outer cylinder 2 escapes from between the gasket 4 and the inner wall of the outer cylinder 2. It should be. Therefore, a step may be formed as long as there is a difference in air escape between the inner diameter (L) and the inner diameter (M). The plug body 5 is a convex rib 11
To avoid the gasket 4 with a certain space from the injection port 2A.
The gasket 4 is finally arranged on the sliding portion 2B of the outer cylinder 2. The injection 6 is steam-sterilized and accommodated in the outer cylinder 2 between the gasket 4 and the stopper 5.

Next, the method of manufacturing the syringe 1 will be described. First, the insertion opening 2C, the ridge rib 11, and the protrusion 14 that spread out toward the end are accurately formed in the outer cylinder 2 by injection molding. In this case, the insertion opening 2C is widened toward the end, and the convex ribs 11 are formed in a taper shape in the axial direction of the outer cylinder 2, so that the outer cylinder 2 can be accurately die-molded without being distorted. Accurate molding is possible with the above-mentioned amorphous polyolefin. As shown in FIG. 3A, the injection needle 7 is attached to the tip of the molded outer cylinder 2, and the plug 5 is inserted into the outer cylinder 2. The plug body 5 is arranged with a width of about 5 from the formed convex rib 11. As shown in FIG. 3 (B), the injection agent 6 is filled into the outer cylinder 2 through the insertion opening 2C of the gasket 4, and the liquid level higher than the position S where the large inner diameter (L) of the insertion opening is formed. Fill up to H.

Next, as shown in FIG. 4, the gasket 4 is inserted from above the opening 2C to fill the outer cylinder 2 with the injection 6 in a liquid-tight manner. In this case, the air on the liquid level surface of the injection 6 escapes through the gap between the outer wall of the gasket 4 and the inner wall of the outer cylinder 2 as the gasket 4 descends, and the injection 6 is filled without air remaining. This is achieved by the difference between the large inner diameter (L) of the insertion opening 2C and the inner diameter (M) of the sliding portion 2B. When the injection agent 6 is stored in such a state where air remains, even if a pressure difference between the outside and the inside occurs during high-pressure steam sterilization, almost no expansion or contraction change due to air is seen in the outer cylinder 2. Therefore, there is no possibility that the outer cylinder 2 made of a thermoplastic resin will be thermally deformed. Therefore, there is no problem in the slidability of the gasket 4 during use. After the gasket 4 is pushed down to the sliding portion 2B as shown in FIG. 1, the injection 6 together with the outer cylinder 2 is sterilized under high pressure steam. The plunger 3 may be attached to the gasket 4 during the high-pressure steam sterilization.
High-pressure steam sterilization is preferably carried out by steam sterilization at 105 ° C to 140 ° C, particularly preferably 105 ° C to 125 ° C. Within such a range, sterilization will be ensured, while
The risk of thermal deformation of the outer cylinder 2 and the like is reduced.

Next, the use of the syringe 1 of this embodiment will be described with reference to FIGS. 1, 5 and 6, and the plunger 3 is pushed in from the state of the syringe of FIG. 1 to the state shown in FIG. In this case, when the plunger 3 is pushed in, the plug 5 is interlocked and pushed toward the injection port 2A side, and the convex rib 11 bites into the outer peripheral wall of the plug 5. As a result, the outer peripheral wall of the stopper 5 is deformed, and a gap is created between the outer peripheral wall of the stopper 5 and the inner wall of the outer cylinder 2, and the injection 6 between the stopper 5 and the gasket 4 passes through the gap. And can flow into the injection port 2A side. In this state, while controlling the pushing of the plunger 3, all the air in the outer cylinder 2 is pushed out, and then the injection needle 7 is pierced into the patient. As shown in FIG. 6, the plunger 3 is completely pushed in to complete the administration of the injection 6 to the patient. In the method of filling the injection through the insertion opening of the gasket as described above, it is not necessary to provide a sealing cap at the injection port as shown in FIG. The injection needle 7 can be attached to the outlet or the like in advance.

Next, the syringe of the second embodiment of the present invention will be explained with reference to FIGS. FIG. 7 is a side sectional view of the second embodiment of the syringe of the present invention. 8 to 10 are side sectional views showing a state in which the plunger of the syringe of the second embodiment is pushed in. The two-component syringe 21 of the first embodiment shown in FIGS. 7 to 10 has an outer cylinder 2 having an injection port 2A at the tip of which an injection needle 7 is attached, and a gasket 4 attached to the outer cylinder 2. The plunger 3 is inserted into the outer cylinder 2, and the stopper 5 is arranged in the inner portion of the distal end of the outer cylinder 2 to close the injection port 2A and the injection 6 between the stopper 5 and the gasket 4.
Since A and 6B are liquid-tightly filled and have substantially the same members and structures as those of the syringe 1 of the first embodiment, the same reference numerals as those of the syringe 1 of the first embodiment are given to these members and the details thereof will be given. The description is omitted. Further, the outer cylinder 2 of the syringe 21 is a molded product of a thermoplastic resin, and the plug body 5 is provided on the gasket 4 side with a certain distance from the injection port 2A, and is provided outside the space between the plug body 5 and the injection port 2A. Since the ribs 11, 11, ... That extend in the axial direction of the outer cylinder 2 are formed on the inner wall of the cylinder 2 portion, the members and the structure are substantially the same as the syringe 1 of the first embodiment. Such members are given the same reference numerals as those of the syringe 1 of the first embodiment, and detailed description thereof will be omitted.

As shown in FIG. 7, the syringe 21 differs from the syringe 1 in that the insertion opening 2C of the outer cylinder 2 is formed thin.
The inner diameter (L) is larger than the inner diameter (M) of the sliding portion 2B. Further, the formation start position of the large diameter portion of the insertion opening 2C is formed by the tapered surface 23, and the gasket 4 is formed by the sliding portion 2B.
It is easy to be inserted and guided in. Further, a partition plug body 22 is provided between the gasket 4 and the plug body 5 in the outer cylinder 2, and the partition plug body 22 is filled with injection agents 6A and 6B having different components. On the inner wall surface of the outer tube 2 between the plug body 5 and the injection port 2A, a plurality of elongated ribs 11 having the same length as the syringe 1 of the first embodiment are formed in the axial direction of the outer tube 2. ing. The formation position of the convex rib 11 or the length thereof is determined by the position where the plug body 5 is elastically deformed and a gap is formed between the outer peripheral wall of the plug body 5 or the partition plug body 22 and the inner wall of the outer cylinder 2. It

The outer cylinder 2 of the syringe 21 is formed longer than before. As with the gasket 4 and the plug 5, the partition plug 22 may be elastic enough to maintain liquid tightness with the inner wall of the outer cylinder 2. Specifically, the same material as the rubber gasket and the rubber stopper is used. Plug 5 and partition plug 22
The injection agent 6A is accommodated in the space between them, and the injection agent 6B is accommodated between the partition plug body 22 and the gasket 4. For example, in this embodiment, the injection 6A is a local anesthetic, and the injection 6B is a painful injection. High-pressure steam sterilization is performed for sterilization of the injections 6A and 6B, and aseptic filling can be performed in addition to this, but high-pressure steam sterilization is desirable to ensure sterilization. High-pressure steam sterilization has a temperature of 105 ° C to 1
It is in the range of 40 ° C., but especially when the temperature is 105 ° C. to 125 ° C.
It is desirable to be in the range of ° C. Within this range,
The outer cylinder 2 is unlikely to be deformed by heat and pressure.

Next, the method of manufacturing the syringe 21 will be described. First, the protruding rib 11 and the projection 14 are accurately formed on the outer cylinder 2 together with the insertion opening 2C by injection molding.
The stopper 5 is inserted into the outer cylinder 2 to a predetermined depth, and the injection 6A is filled until the liquid level reaches the large diameter inner diameter portion of the opening 2C.
After filling the injection 6A, the partition plug 22 is inserted from the upper part to the outer cylinder 2
Insert it to the specified depth with no air remaining inside.
As a result, the plug body 5 also moves to a certain depth at the same time.
Next, the injection 6B is filled in the outer cylinder 2, and the injection 6B is filled until the liquid level reaches the large diameter inner diameter portion of the opening 2C. After the filling, the gasket 4 is inserted into the outer cylinder 2 in a state where no air remains. Then, the plunger 4 is attached to the gasket 4.
Then, the injection needle 2 with a protector is attached to the injection port 2A. In this state, the syringe 21 is sterilized by high-pressure steam to sterilize the injections 6A and 6B.

Next, for injection using the two-component syringe 21 of this embodiment, the plunger 3 is pushed in from the state shown in FIG. 7, and the stopper 5 and the partition stopper are inserted through the injections 6A and 6B. The body 22 is pushed to the position shown in FIG. When pushed to the position shown in FIG. 8, a gap is formed between the outer peripheral wall of the plug 5 and the inner wall of the outer cylinder 2, and the plug 5 stops moving even if the plunger 3 is pushed. Therefore, the injection 6A is suddenly flown into the space 99, but does not reach the needle tip 7 and does not leak. After the air in the space 99 is expelled, the injection 6A is injected and administered to the patient. When the partition plug body 22 is pushed by the plunger 3 to the position shown in FIG. 9, a space is formed between the outer peripheral wall of the partition plug body 22 and the inner wall of the outer cylinder 2, and the partition plug body 22 is fixed to the plunger 3
The movement stops even if is pressed. Then, the injection agent 6B is flown into the ejection port 2A side, the plunger 3 is further pushed, and is injected into the patient's body. Therefore, the local anesthetic is first administered to the patient, and the painful injection 6B can be administered while the pain is paralyzed.

[0023]

As described above, in the syringe of the present invention, the outer cylinder is formed such that the inner diameter (L) of the insertion opening of the gasket is larger than the inner diameter (M) of the sliding portion of the gasket. Since it is a thermoplastic resin molded product, the injection is filled into the outer cylinder through the insertion opening of the gasket, and is filled up to a liquid level higher than the position where the inner diameter (L) of the insertion opening is formed. In the above, the gasket is inserted from above the opening to liquid-tightly fill the injection in the outer cylinder, and thereafter, the injection is sterilized by high-pressure steam together with the outer cylinder. At the time of filling, almost no air is mixed in, the high-pressure steam sterilization is not hindered, and an injection needle can be attached to the injection port in advance.

[Brief description of drawings]

FIG. 1 is a side sectional view of a first embodiment of a syringe of the present invention.

2 is a cross-sectional view of the syringe taken along line I-I of FIG.

3A and 3B are side cross-sectional views of the injector of FIG. 1 during assembly.

FIG. 4 is a side sectional view of the syringe of FIG. 1 during assembly.

FIG. 5 is a side sectional view of the syringe according to the first embodiment when in use.

FIG. 6 is a side sectional view of the syringe in use according to the first embodiment.

FIG. 7 is a side sectional view of a second embodiment of the syringe of the present invention.

FIG. 8 is a side sectional view showing a state where the plunger of the syringe of the second embodiment is pushed in.

FIG. 9 is a side sectional view showing a state where the plunger of the syringe of the second embodiment is pushed in.

FIG. 10 is a side sectional view showing a state where the plunger of the syringe of the second embodiment is pushed in.

[Explanation of symbols]

 1, 21 Syringe 2 Outer cylinder 2A Outlet of outer cylinder 2C Insertion opening 3 Plunger 4 Gasket 5 Plug 6 Injection liquid 7 Injection needle 11 Convex rib 13 Outer cylinder shoulder 14 Projection

Claims (2)

[Claims] 1. In a syringe in which an injection agent is contained in advance in an outer cylinder, the outer cylinder has an inner diameter (L) of a gasket insertion opening portion larger than an inner diameter (M) of a sliding portion of the gasket. A syringe characterized by being a formed thermoplastic resin article. 2. The syringe according to claim 1, wherein the injection agent is filled in the outer cylinder through an insertion opening of the gasket, and is higher than a position where a large inner diameter (L) of the insertion opening is formed. To the liquid level, and then insert the gasket from above the opening to fill the injection in a liquid-tight manner in the outer cylinder, and then sterilize the injection with the outer cylinder with high pressure steam. A method for manufacturing a characteristic syringe.