JPH05337180A - Syringe mite needle storing mechanism - Google Patents

Abstract

PURPOSE:To avoid an exterior wound caused by a needle pipe and infection caused by a virus etc., by retreating the needle pipe in the outer cylinder by means of a spring provided between a needle pipe holding plug at the apex of a suction core sliding in the outer cylinder of a syringe and a needle hole stopping plug and closing the needle hole with the stopping plug. CONSTITUTION:A suction core 2 is pulled out along the inside of an outer cylinder 1 of a syringe to suck a medical agent and a needle pipe 3 is pierced into a disease part to inject the medical agent in a body by pushing the suction core 2. The base part of the needle pipe 3 is held by means of a needle pipe holding plug 4 provided at the apex of the suction core 2 and the apex thereof is projected outside through a hole of a needle hole stopping plug to push out the suction core 2 to the outside by means of a spring 6 between the needle pipe holding plug 4 and the needle hole stopping plug 5. After injection is finished, by pushing the suction core 2, locking made by a recessed part 8 of the outer cylinder and a projection of the holding plug 4 is released. When a hand is apart from it, the suction core 2 is pushed out and the needle pipe 3 is stored in the outer cylinder 1 and the stopping plug 5 is rotated to close the outlet. It is possible thereby to avoid an exterior wound caused by the needle pipe and infection caused by an adhering virus, etc.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe having a mechanism capable of storing an injection needle inside the syringe after the injection is completed. More specifically, the injection needle is stored inside the syringe by the action of a spring after the injection is completed. At the same time, the syringe is a syringe in which the mounting hole of the needle is closed to prevent the blood and the like of the patient adhering to the needle tip from leaking to the outside.

[0002]

2. Description of the Related Art At present, syringes are widely used mainly in the medical field. Recently, most of them are disposable type made of plastic, and the needle is covered with a plastic cap before use.
The tip of the needle cannot be touched directly with the finger. After use, the needle is capped again or only the needle is removed and discarded. However, after the cap of the injection needle is removed and used, the fingertip is often accidentally pierced while the needle tip is exposed until the injection needle is capped and discarded again. This preventive measure has become a major problem among clinical persons because the patient who is injected is infected with hepatitis virus or the like.

Particularly in Western countries, cases of AIDS infection have been reported, which causes serious anxiety. In addition, there is concern about such a situation in Japan in the future.

Considering the course of infection with virus and the like, before use of the syringe, even if the injection needle is accidentally stabbed in the fingertip, only an injury occurs, and there is no possibility of infection. There is a problem between the time when the syringe is used and the time when it is discarded in the processing container. After use, infection can be prevented if the needle can be stored inside the syringe by an operation that does not cause the needle to stick to the fingertip. Furthermore, considering that the final treatment will be completed after a lot of manpower after the medical staff throws it in the treatment container, the needle is stored inside the syringe and at the same time, the mounting hole for the needle at the tip of the syringe is inserted. It is also necessary to close it so that the patient's blood or the like attached to the needle tip does not leak outside.

Since the mechanism for taking out the injection needle from the inside of the syringe only when it is used or storing the injection needle inside the injection syringe after use becomes considerably complicated, such a mechanism is added to the conventional disposable type injector. Very few attempts have been made to do so.

As a few examples of disclosure, PCT / EP89 / 01408
In Fig. 1, there is shown a mechanism for inserting and retracting an injection needle by combining about 10 plastic molded parts having complicated shapes inside a plastic syringe and utilizing the force of a spring. When using the needle stored inside the syringe before use, by pushing the sucker (cuus) of the syringe, the injection needle pops out from the tip of the syringe and is automatically attached to suck the injection solution. When the sucker is further pushed in after injecting it into the patient, the lock is released and the needle is retracted inside the syringe by the force of the spring. Further, the injection needle once stored after use does not come out again even if the sucker is pushed in.

However, a problem with this mechanism is that the injection needle is bent in advance, deformed during assembly to be straightened, and when the injection needle is retracted after use, the injection needle returns to its original shape, resulting in a bent shape. , It is structured so that it does not go out even if it is pushed. However, since the degree of structural deformation cannot be increased, if the part that holds the injection needle moves a little, the injection needle is likely to come out, which is dangerous. Further, it is difficult to completely seal the mechanical part, and the injection solution may enter the part. Furthermore, since the number of parts is large and the shape is complicated, there are many parts that require delicate preparation during assembly.

With this mechanism, the injection needle is stored inside the syringe even before use, but infection with viruses and the like cannot occur before use, so it is not necessary to add a too complicated mechanism for this purpose. Not considered.

[0009]

SUMMARY OF THE INVENTION The present invention uses a simple mechanism to safely store the injection needle inside the syringe after the injection is completed, and at the same time close the needle hole at the tip of the injection syringe so that the injection needle is accidentally moved to the outside. It is an object of the present invention to provide a syringe that prevents the blood, etc. of a patient adhering to the needle tip from leaking to the outside while preventing it from coming out.

[0010]

According to the present invention, when a syringe is handled, the injection needle is accidentally stuck in the fingertip and causes an infection accident such as virus etc. only after the end of injection until the syringe is thrown into the processing container. Focusing on the fact that a spring is used, an idea of a mechanism that uses a simple mechanism to safely store the injection needle inside the syringe after completion of injection and at the same time close the mounting hole of the injection needle at the tip of the injection syringe Thus, the present invention has been reached based on this.

That is, the outer cylinder 1 of the syringe, the sucker 2, the needle tube 3, the needle tube holding plug 4, the needle hole closing plug 5, the spring 6 connecting the needle tube holding plug and the needle hole closing plug, and the outer tube and the needle tube. It consists of a lock mechanism between the holding plugs, and the needle holding plug is fixed in the outer cylinder by the locking mechanism until the end of injection, but when the sucker is pushed further after the injection, the needle holding plug is locked. When the needle tube holding plug is pushed in and the force holding the sucker is loosened, the needle tube holding plug is pushed up by the spring and the needle tube is stored inside the outer cylinder.
A syringe with a needle storing mechanism, characterized in that the needle hole stopper is moved by a spring to close the needle hole at the tip of the outer cylinder, and / or the outer cylinder 1 is provided with a portion 27 of which the inner diameter changes. When the inner diameter of the rear part is larger than that of the front part and the needle tube holding plug is pushed up to the rear part of the syringe by the spring, the inner diameter of the rear part of the outer tube is large, so there is a gap between the needle tube holding plug and the inner surface of the outer tube, which reduces frictional resistance. It is a syringe with an injection needle retracting mechanism. Further, the present invention relates to a specific mechanism for closing the lock of the needle tube holding plug and the needle hole.

In the above claims 1, 2, 3 and 4, the operation described as pushing up or pushing down the needle tube holding plug and the like is performed in the upward direction (rear portion of the syringe) or the downward direction in the syringe shown in FIG. It means the movement to move in the direction of (the front of the syringe). The present invention will be described in detail below.

As a safety measure in handling the injection needle, when broadly considering not only infection of hepatitis virus etc. but also injury of fingertip, the injection needle is stored inside the syringe before use, and one-touch injection at the time of use Ideally, the needle can be stored inside with one touch so that the patient's blood attached to the needle tip after use does not leak outside. However, it is unavoidable that this requires a considerably complicated mechanism. Considering the degree of injury, mere fingertip puncture wounds are extremely minor compared to infections with viruses and the like. Therefore, even if the needle is not retracted before use, it can be safely retracted after use, and the needle does not come out again when strong force is applied. Infection can be prevented if blood etc. can be prevented from leaking outside. Therefore, if only this operation is targeted, the mechanism should be greatly simplified.

From this point of view, the present invention provides a movable needle tube holding plug and a locking and unlocking mechanism therefor inside the syringe, and utilizes the force of a spring connecting the needle tube holding plug and the needle hole closing plug. The mechanism is greatly simplified by retracting the injection needle and closing the needle hole.

The present invention will be described in detail with reference to the drawings. 1, 2 and 3 are cross-sectional views of one embodiment of the syringe of the present invention. FIG. 1 is a state before use, FIG. 2 is a state in which an injection solution 29 is inhaled inside an outer cylinder, and FIG. It shows a state in which the needle is stored. The outer cylinder 1 and the sucker 2 of the syringe can be widely used as long as they are made of a transparent material that does not contain a component that is eluted in the injection solution, like a commonly used syringe. Usually, plastic or glass is used. Although glass is more chemically stable than plastic, it is difficult and expensive to process into complex shapes, while plastic is easier and cheaper to mold into complex shapes.
For this reason, most recent disposable syringes are made of plastic, and the tip of the sucker is covered with synthetic rubber, natural rubber, or plastic having a high elasticity, and a highly airtight structure is often adopted.

Since the syringe of the present invention needs to have a mechanism for storing the injection needle inside, it is preferably made of plastic which is easy to process, and the tip of the sucker is covered with rubber or the like to have a highly airtight structure. preferable. The inner surface of the outer cylinder is provided with a recess 8 as a part of a lock mechanism for fixing the position of the needle holding plug 4, and a stopper 26 for preventing the sucker from falling off.

Since the needle tube 3 is provided with a mechanism for storing the injection needle inside the syringe, the same needle tube as the normal needle tube can be used except that it is 10 to 15 mm longer than the normal needle tube.

The needle tube holding plug 4 holds the needle tube, has a function of locking to the outer cylinder, and a function of holding one end of the spring 6. Therefore, the material is not particularly limited because it has a complicated shape, but a plastic molded product is preferable. FIG. 4 shows an enlarged cross-sectional view of one embodiment of the method, in which the needle tube is adhered and fixed to a retaining plug at 12 and the injection solution is
It is injected through the inside of a 12-needle tube.

The protrusion 9 of the needle tube holding plug and the concave portion 8 of the outer tube are provided at two positions on the circumference of the needle tube holding plug and the outer tube as shown in FIG. 5A which is a sectional view taken along the line AA 'of FIG. It is provided. The protrusion 9 meshes with the recess 8 of the outer cylinder, and the spring 6 connected to the spring receiving portion 16 pushes up from the bottom to the top in FIG.

When the needle tube holding plug 4 is pushed down, the projection 9 comes into contact with the lower end 14 of the concave portion 8 of the outer cylinder and is deformed, moving to the position 15 and disengaged. Needle tube stopper and cam of outer cylinder 1
0 and 11 are sectional views taken along the line BB 'of FIG. 4, and as shown in FIG. 5 (b),
It is provided in two places on the circumference. Further, FIG. 6 (a) is a perspective view of the engaging portion of the cam. When the holding plug is lowered, the cams 10 and 11 come into contact with each other, and the tip 17 of the 11 is slanted down along the slope of 10 as shown in FIG. 6 (b) → (c) → (d). Stop in position while the needle retainer
It rotates by the circumference up to. Therefore, when the force of pressing the needle tube holding plug is loosened and the needle tube holding plug is pushed up by the action of the spring 6, the protrusion 9 does not engage with the concave portion 8 and is pushed up until the spring is restored.

The above shows one mode of the locking mechanism. The needle tube holding plug 4 is fixed at a fixed position until the end of the injection, and the lock is released by pushing the sucker after the end of the injection. When the force of pushing is released, the needle tube holding plug is pushed up by the spring, but any mechanism may be adopted as long as it is not locked again.

If necessary, the packing 23 can be attached along the circumference of the needle tube holding plug 4. As a result, the airtightness of the contact portion between the needle holding plug and the inner surface of the outer cylinder is improved,
It is possible to completely prevent the injection liquid from leaking between the needle tube holding plug and the tip of the outer cylinder.

7 (a) and 7 (b) show the state of the needle tip and the needle hole closing plug before and after use. The needle hole closing plug 5 is provided with a spring receiving portion 20 and a small hole 7, and a spring 6 is connected to the spring receiving portion 20. Therefore, the material is not particularly limited because it has a complicated shape.
Plastic moldings are preferred. The needle tube 3 is held by penetrating the small hole 7 of the needle hole closing plug 5 in the initial state, but at the same time when the injection needle is pushed up and comes off the small hole,
The action of pushing down the needle hole closing plug of the spring works, and the closing plug is pushed down from the position of 5 to rotate and becomes the state of 21, so that the needle hole 22 is closed. Further, the closing plug is fixed in the state of 21 by the action of the spring.

FIGS. 8 (a) and 8 (b) show other modes of the needle hole closing plug before and after use.
The closing plug changes from 24 states before closing to 25 states after closing. When the needle hole closing plug is formed in such a shape, the needle hole can be closed more completely, as can be seen from the relationship between the closing plug 25 and the needle hole 22.

Others The needle hole stopper may be of any shape as long as it can close the needle hole when the injection needle is pulled out from the small hole.

Further, according to the present invention, as shown in FIG. 9, the inner surface of the outer cylinder 1 may be provided with a portion 27 having a variable inner diameter so that the inner diameter of the rear portion is larger than that of the front portion of the outer cylinder. FIG. 9 is a sectional view of a syringe having the above-described aspect of the present invention.
(a) shows a state in which the injection needle is retracted before use and at the end of injection, and (b) shows a state after the use. In FIG. 9, a portion 27 where the inner diameter of the outer cylinder changes is provided in a portion where the upper end of the needle tube holding plug 4 contacts the inner surface of the outer cylinder, and the inner diameter of the rear portion is larger than that of the lower portion, that is, the front portion of the syringe. Therefore, since the tip end 28 of the sucker 2 is in contact with the outer cylinder at the portion where the inner diameter of the outer cylinder is large and airtightness is maintained, and the needle tube holding plug 4 is kept airtight at the packing 23 portion, the inner diameter of the outer cylinder is The small part is in contact with the outer cylinder.

When the sucker 2 is further pushed in after the injection is completed, the lock fixing the needle tube holding plug 4 is released and the needle tube holding plug is pushed in. Then, when the force holding the sucker is released,
The needle 6 holding plug is pushed up by the spring 6. At this time, the spring must push up the needle tube holding plug 23 against the frictional resistance generated between the packing 23 and the inner surface of the outer cylinder and between the tip 28 of the suction member 2 and the inner surface of the outer cylinder. However, if a portion 27 of which the inner diameter changes is provided on the inner surface of the outer cylinder so that the inner diameter of the rear portion is larger than the front portion of the outer cylinder, the frictional resistance generated between the tip 28 of the sucker and the inner surface of the outer cylinder. However, the frictional resistance generated between the packing 23 of the needle retaining plug and the inner surface of the outer cylinder is significantly reduced.

FIG. 10 shows details of the contact state between the needle tube holding plug 4 and the inner surface of the outer cylinder. The needle tube holding plug is kept airtight by contacting the portion of the packing 23 where the inner diameter of the outer cylinder is small.
When the needle holding plug is pushed up by the spring 6,
Friction resistance occurs between the packing and the inner surface of the outer tube until the packing reaches the inner surface 27 of the outer tube. There is a gap between the two and almost no friction occurs. Therefore, the frictional resistance generated when pushing up the needle holding plug and the sucker is significantly reduced. The state is shown in FIG. 9 (b).
The difference in the inner diameter of the inner surface 27 of the outer cylinder 1 is not particularly limited, but it is preferably about 1 mm in a normal syringe.

The frictional resistance generated at that time is determined by the packing 23.
The friction resistance generated between the tip 28 of the packing 23 and the sucker and the inner surface of the outer cylinder is the sum of the friction resistance generated between the tip 28 of the packing 23 and the sucker and the inner surface of the outer cylinder for a short time until the inner surface 27 of the outer cylinder 27 is reached. During most of the time after passing through the portion of, the resistance generated between the packing and the inner surface of the outer cylinder almost disappears, and only the frictional resistance generated between the tip 28 of the sucker and the inner surface of the outer cylinder. Therefore, it will be significantly reduced.

After the injection is completed, the sucker 2 is further pushed in to release the lock fixing the needle tube holding plug 4, and the spring is in the most compressed state. Therefore, the spring exerts the greatest repulsive force at the moment when the force for pressing the sucker is released next and the spring starts to push up the needle holding plug and the sucker. At this time, the frictional resistance applied to the spring is the largest, the resistance is greatly reduced thereafter as described above, and the repulsive force of the spring is gradually weakened, so that the force of the spring can be used more effectively. Therefore, compared to a syringe in which the inner surface of the outer cylinder is not provided with the portion 27 of which the inner diameter changes,
Even small springs can be fully functional.

If the spring is made smaller, the structural strength of the entire syringe can be lowered, and there are many merits such as making the vessel wall thinner. Further, as can be seen from FIG. 10, it is preferable that the distance between the packing 23 and the portion 27 where the inner diameter of the outer cylinder changes is as short as possible to reduce the frictional resistance at the time of pushing up.

[0032]

Before use, the syringe of the present invention is fixed at a fixed position in the outer cylinder with the needle tube holding plug 4 locked, and the needle tip is usually covered with a plastic protective cap.
When using a syringe, remove the cap of the needle tip after sterilization,
The sucker 2 is moved to suck the injection solution 29 into the syringe.
At this time, since the needle tube holding plug is locked inside the outer cylinder, the injection liquid enters between the holding plug and the tip of the sucker. Further, since the contact portion between the needle tube holding plug and the inner surface of the outer cylinder is kept airtight, the injection liquid does not leak and enter between the holding plug and the needle hole closing plug.

After the injection is completed, when the sucker is further pushed in until it is stopped, the needle tube holding plug 4 is also pushed down to release the lock, and when the force holding the sucker is released next, the needle tube holding plug is pushed up by the action of the spring. .. At this time, the needle holding cap is prevented from being locked again at the previously locked position, so the needle holding plug is pushed up to the position where the spring is restored, and the needle pipe connected to this is also locked in the outer cylinder. 1
Stored inside.

Since the needle tube is pushed up inside the outer cylinder,
When the needle tube comes out of the small hole 7 of the needle hole closing plug 5, the force of the spring pressing down the needle hole closing plug works to move the needle hole closing plug 5 to the position 21 to close the needle hole 22.

Due to the relationship between the needle tip after use and the needle hole closing plug shown in FIG. 3, even if the sucker is pushed down with a strong force after the needle is once stored, the needle hole closing plug will close the needle hole. Since it is closed, there is no danger that the injection needle will come out.

Further, a portion of which the inner diameter is changed is provided on the inner surface of the outer cylinder so that the inner diameter of the rear portion is larger than that of the front portion of the outer cylinder. After the injection, the sucker is pushed further in, and when the lock that fixed the needle holding cap is released, the spring is in the most compressed state, then the force holding the sucker is loosened, and the spring causes the needle holding cap and The spring exerts the greatest repulsive force at the moment when it starts pushing up the sucker. At this time, the frictional resistance applied to the spring is the largest, the resistance is greatly reduced thereafter as described above, and the repulsive force of the spring also gradually weakens, so the spring force and the frictional resistance match, and the force is more effective. Can be used for Therefore, compared to a syringe in which the inner surface of the outer cylinder is not provided with the portion 27 of which inner diameter is changed, a small spring can sufficiently function.

Furthermore, since a small amount of silicone is usually used in the syringe, this mechanism can be operated very smoothly.

[0038]

INDUSTRIAL APPLICABILITY The present invention is a syringe capable of safely storing the injection needle inside the syringe after using the syringe with a simple mechanism in order to prevent the infection of virus such as hepatitis. Furthermore, the injection needle once stored inside will not be exposed to the outside no matter how it is handled, and the needle hole at the tip will also be closed, so that blood etc. of the patient adhering to the needle tip will not be exposed to the outside. It never leaks. Further, the syringe that has been used once has a structure that cannot be reused.

Therefore, the use of this syringe has a remarkable effect on the prevention of infection of virus and the like, and is also effective for the prevention of AIDS infection which has recently become a problem in many countries around the world.

[Brief description of drawings]

[Figure 1]

[Fig. 2]

FIG. 3 is a cross-sectional view of one embodiment of a syringe with a needle storage mechanism of the present invention, FIG. 1 is a state before use, FIG. 2 is a state in which an injection solution is sucked into the outer cylinder, and FIG. It shows the stored state.

[Figure 4]

5 is an enlarged cross-sectional view of a needle retaining plug and a locking mechanism according to one embodiment of the present invention, and FIGS. 5 (a) and 5 (b) are AA ′ and BB in a direction perpendicular to FIG. It is an expanded sectional view of '.

FIG. 6A is a perspective view of an engaging portion of a cam according to one embodiment of the present invention, and FIGS. 6B, 6C and 6D are time-series representations of operating states of the cam. Of.

FIG. 7 is an enlarged cross-sectional view of a needle tip portion according to one embodiment of the present invention,
(a) shows the state from before use to the end of injection, and (b) shows the state after use.

FIG. 8 is an enlarged cross-sectional view of a needle tip portion according to one embodiment of the present invention,
(a) shows the state from before use to the end of injection, and (b) shows the state after use.

FIG. 9 is a cross-sectional view of one embodiment of the syringe with a needle retracting mechanism of the present invention, (a) showing a state in which the needle is retracted before use and at the end of injection, and (b) after use. ..

FIG. 10 is an enlarged cross-sectional view of a needle tube holding plug and a lock mechanism according to one embodiment of the present invention.

[Explanation of symbols]

 1 syringe outer cylinder 2 syringe sucker 3 needle tube 4 needle tube retaining plug 5 needle hole closing plug 6 spring 7 small hole provided in needle hole closing plug 8 concave portion of outer cylinder 9 needle tube retaining plug projection (locked state) 10 Cam (outer cylinder) 11 Cam (needle retaining plug) 12 Needle retaining portion of needle retaining stopper 13 Injection needle inlet 14 End of recess 8 of outer cylinder 15 Position of protrusion of needle retaining stopper (locked state) 16 Spring attachment part for needle tube retainer plug 17 Cam operation part (needle tube retainer plug) 18 Operation start position of cam operation part (outer cylinder) 19 Operation end position of cam operation part (outer cylinder) 20 Needle hole stopper plug spring Installation part 21 Operation end position of needle hole stopper 22 Needle hole 23 Packing 24 Needle hole stopper (another mode) 25 Operation end position of needle hole stopper (another mode) 26 Stopper 27 Inner diameter of outer cylinder Changing part 28 Tip part of sucker 29 Injection

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[Procedure amendment]

[Submission date] June 17, 1993

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] Brief explanation of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a view showing the use of an embodiment of the syringe with a needle retracting mechanism of the present invention .
A sectional view in the state before use is shown.

FIG. 2 is a diagram showing a case where an injection liquid is sucked into the outer cylinder of the syringe shown in FIG .
The cross-sectional view of the inserted state is shown.

FIG. 3 is a perspective view showing an external cylinder of the injection needle after using the syringe shown in FIG .
The sectional view of the state stored in the inside is shown.

FIG. 4 shows an embodiment of a syringe with a needle retracting mechanism according to the present invention .
FIG. 6 is an enlarged cross-sectional view of the needle tube holding plug and the lock mechanism.

5 (a) and 5 (b) are needle tube holding plugs and locks of FIG.
The enlarged cross section of A-A 'and BB' of the mechanism is shown.
You

FIG. 6A is a perspective view of an engaging portion of a cam of one embodiment of the present invention, and FIGS. 6B, 6C, and 6D are time-series representations of operating states of the cam. Of.

FIG. 7 is an enlarged cross-sectional view of a needle tip portion according to one embodiment of the present invention,
(A) shows the state before use until the end of injection, and (b) shows the state after use.

FIG. 8 is an enlarged cross-sectional view of a needle tip portion according to one embodiment of the present invention,
(A) shows the state before use until the end of injection, and (b) shows the state after use.

FIG. 9 is a cross-sectional view of one embodiment of a syringe with a needle storage mechanism according to the present invention, where (a) shows a state in which the injection needle is stored before use and at the end of injection, and (b) after use. ..

FIG. 10 is an enlarged cross-sectional view of a needle tube holding plug and a lock mechanism according to one aspect of the present invention.

[Explanation of symbols]   1   Syringe barrel   Two   Syringe sucker   Three   Needle tube   Four   Needle retaining plug   5   Needle hole stopper   6   spring   7   Small hole on the needle hole stopper   8   Recess of outer cylinder   9   Protrusion of the needle holding plug (locked state)   10   Cam (outer cylinder)   11   Cam (Needle tube holding plug)   12   Needle holding part of needle holding plug   Thirteen   Injection needle entrance   I4   End of the recess 8 of the outer cylinder   15   Position of the protrusion on the needle holder plug (with the lock released)   16   Spring attachment part of needle holder   17   Cam operating part (Needle tube holding plug)   18   Actuation start position of the actuating part of the cam (outer cylinder)   19   Operation end position of cam operating part (outer cylinder)   20   Spring mounting part for needle hole stopper   21   Operation end position of needle hole stopper   22   Needle hole   23   packing   24   Needle hole stopper (another mode)   25   Operation end position of the needle hole closing plug (another mode)   26   stopper   27   The part where the inner diameter of the outer cylinder changes   28   The tip of the sucker   29   Injection solution

Claims (4)

[Claims] 1. An outer cylinder 1, a sucker 2, a needle tube 3, a needle tube stopper 4, a needle hole stopper 5, a spring 6 connecting the needle holder stopper and the needle hole stopper, and an outer cylinder and a needle tube. It consists of a lock mechanism between the holding plugs, and the needle holding plug is fixed in the outer cylinder by the locking mechanism until the end of injection, but when the sucker is pushed further after the injection, the needle holding plug is locked. When the needle tube holding plug is pushed in and the force holding the sucker is released, the needle tube holding plug is pushed up by the spring, the injection needle is stored inside the outer cylinder, and the spring closes the needle hole closing plug. A syringe with an injection needle retracting mechanism, which moves to close the needle hole at the tip of the outer cylinder. 2. An outer cylinder 1, a sucker 2, a needle tube 3, a needle tube retaining plug 4, a needle hole closing stopper 5, a spring 6 connecting the needle tube retaining stopper and the needle hole closing stopper, and an outer cylinder and a needle tube. It consists of a lock mechanism between the holding plugs, and the outer cylinder 1 has a portion 27 where the inner diameter changes.
The inner diameter of the rear part is larger than that of the front part of the outer cylinder, and the needle retaining plug is fixed in the outer cylinder by the lock mechanism until the end of injection. When the lock that has been fixed is released and the needle holding cap is pushed in, and then the force that presses the sucker is released, the needle holding plug is pushed up by the spring, the injection needle is stored inside the outer cylinder, and the spring Although the needle hole closing plug moves to close the needle hole at the tip of the outer tube, when the needle tube holding plug is pushed up, the inner diameter of the rear part of the outer tube is large and a gap is created between the needle tube holding plug and the inner surface of the outer tube, causing friction. A syringe with a needle retracting mechanism, which has reduced resistance. 3. The needle hole closing plug is provided with a small hole 7, and the injection needle is held through the small hole until the end of injection. However, the lock is released and the holding plug is pushed up, so that the injection needle has a small hole. The syringe with an injection needle retracting mechanism according to claim 1 or 2, which has a mechanism in which the needle hole closing plug is moved by a spring to close the needle hole when the needle hole is closed. 4. The lock mechanism comprises a recess 8 provided on the inner surface of the outer cylinder of the syringe and a projection 9 provided on a portion of the needle tube holding plug contacting the inner surface of the outer tube. The protrusion meshes with the recess of the outer cylinder to secure the needle retaining plug.However, if the sucker is pushed down further after the injection is completed, the protrusion that had fixed the needle retaining stopper will be pushed down and the needle retains. A mechanism for preventing the stopper from being locked again when the stopper is twisted by the action of the cams 10 and 11 and the needle retaining plug is pushed upward by the action of the spring.
2. A syringe with a needle retracting mechanism according to 2 above. [0001]