JP2001340457A - Replacement needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a replacement needle to give a person a smooth injection easily with one hand without giving fear to the person by directly pricking a needle into the body without exposure of the needle. SOLUTION: An injection needle 1 has a needle holding member 10, a needle 3, an injection cap 20 of opaque materials to cover a needle tip 3a and attached to the needle holding member 10, and a rear protection cap 30 to cover the base part 3b side of the needle 3 and attached to the needle holding member 10. In the needle holding member 10, a sliding guide part 16 where a guide side 24 of the injection cap 20 slides is formed, and the rear protection cap 30 is detached, and attached to a syringe. After contacting an arc face 21 of the injection cap 20 to the neck of a tooth, the needle tip 3a of the needle 3 is semi-automatically pushed through a needle hole 22 of the injection cap 20 and injected to the neck of tooth by pushing the syringe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a replacement syringe needle which is configured to be mountable on a syringe barrel of a syringe and has a protective cap for protecting the needle.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 15, a replacement injection needle 51 has a needle distal end 53a and a needle rear end 53b in which a needle 53 held by a holding member 52 projects to both sides of the holding member 52.
Are covered and protected by the transparent front cap 54 and the rear end cap 55. The holding member 52 is
The distal end portion is formed in a wall shape having a needle insertion hole 52a, the rear end portion is formed in a hollow shape having a flange portion 52b, and the outer peripheral surface of the distal end portion is tapered. The female screw part 52c to be attached to the injection cylinder was formed in the hollow portion at the rear end.

A needle tip 53 is provided on the outer peripheral surface of the holding member 52.
a press-fitting the tip cap 54 for protecting the
The rear end cap 55 was externally fitted to the front end cap 54 into which the 2 was press-fitted. The front end cap 54 has an opening at the rear end, is fitted to the holding member 52, and has a flange 5 on the outer peripheral surface.
4a, the rear end face of the collar portion 54a is formed so as to be in contact with the front end face of the rear end cap 55, and is arranged as an insertion stopper for the rear end cap. Rear end cap 55
Is formed in a stepped cylindrical shape with an open front end, and an inner step end surface 55a is formed so as to be able to contact the flange portion 52b of the holding member 52.

[0004] When performing injection using the injection needle 51, first, the rear end cap 55 is attached to the holding member 5.
2 and detached from the distal end cap 54 fitted thereto, and attached to the syringe. At this time, the needle rear end 53b of the needle 53 is inserted into the distal end of the syringe barrel, and the male thread formed on the outer peripheral surface of the distal end of the syringe is screwed into the female thread 52c of the holding member 52, and the tip cap is closed. The flange 54 a is brought into contact with the rear end face of the flange 54 a. Thereafter, the distal end cap 54 is removed from the holding member 52, and the needle is inserted into the insertion position while the needle distal end portion 53a of the needle 53 is exposed to perform injection.

[0005]

However, in general, patients (particularly, patients with disabilities, children, etc.) often have a fear of injecting only injections. Furthermore, by looking at the injection needle exposed from the syringe barrel when injecting,
His fears grew even higher, often requiring refusal and escape, making treatment more difficult. The conventional injection needle 51 removes a cap 54 for protecting the needle 53 when performing injection, exposing the needle 53,
The patient's fear could not be removed because it was configured to hit the affected area.

[0006] In addition, since the conventional injection needle has an exposed needle, it is necessary to remove the cap 54 with one hand and operate the syringe with the other hand at the time of injection. The work is exaggerated, which may give a feeling of pressure to the patient, and may cause an erroneous injection of inserting the needle out of the intended position.

In addition, since the conventional injection needle has a detachable distal end cap for covering the distal end portion of the needle, after use, the distal end cap is attached to the injection needle removed from the syringe and disposed of. . At the time of attaching the tip cap, an erroneous needle accident that a needle is stuck in the hand has occurred.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem, and performs an injection without showing a needle to a patient so that a smooth treatment can be performed without the fear of the needle of the patient, and the treatment can be easily performed with one hand. It is an object of the present invention to provide a replacement needle configured to be able to be injected into a needle, and not to cause a needle accident at the time of disposal.

[0009]

The replacement injection needle according to the present invention has the following configuration in order to solve the above-mentioned problems. That is, a replacement injection needle configured to be attachable to a syringe barrel of a syringe, a needle holding means for holding a needle to be inserted, and a cap for covering a needle tip side of the needle at one end of the needle holding means. Means, and protection means for covering the base of the needle at the other end of the needle holding means, wherein the cap means is formed opaque and has an arc surface having a needle insertion hole at one end. Formed and slidably disposed on the needle holding means with an opening at the other end,
The needle holding means includes a holding wall portion for holding the needle to be inserted, a connecting portion for being attached to the syringe barrel at the base of the needle, and for sliding the injection cap on the outer peripheral surface. And a stopper provided at the tip of the sliding guide and preventing the cap from being detached from the needle holding means. It is assumed that.

Further, the sliding guide portion of the needle holding means is formed to have a tapered surface tapering toward the tip end of the needle holding means, and the cap means is provided with a taper of the sliding guide portion. It is desirable that the opening of the cap means be formed of an elastic member so that the diameter of the opening can be increased when sliding along the surface.

It is further preferable that the retaining means is formed so as to protrude radially from the outer peripheral surface of the distal end of the sliding guide with respect to the axis of the needle holding means.

It is more preferable that a scale indicating the length of the needle projecting from the injection cap is formed on the outer peripheral surface of the needle holding member.

[0013]

According to the present invention, since the replacement injection needle is configured as described above, it can be used in a state in which the cap is attached to the needle holding means after being attached to the syringe barrel. Then, the arc surface formed at the tip of the cap means is brought into contact with the needle insertion position. Then, by pushing out the syringe barrel while the cap means is in contact with the correct insertion position, the needle holding means connected to the syringe barrel is moved toward the insertion position. By moving the needle holding means with respect to the cap means, the cap means is moved along the sliding guide portion of the needle holding means, and at the same time, the needle point is inserted through the needle insertion hole of the cap means at the insertion position. It will be inserted. Then, when the needle is inserted, the medicinal solution is injected by pushing out the piston of the syringe, and injection can be performed.

Therefore, when injecting a patient,
During the injection, the patient can insert the needle into the correct position without showing the needle at all, and since the injection position only shows the arcuate surface of the cap means, the patient will not be afraid It is less likely to cause rejection. Therefore, the treatment can be performed smoothly.

Further, since the stopper means is formed at the tip of the needle holding means, when the cap means is slidably disposed on the needle holding means, the cap means is not provided with the needle holding means. Even when the syringe needle is not attached to the syringe barrel or is attached to the syringe barrel, the cap means is not likely to be detached from the needle holding means and the needle is not exposed even when the syringe needle is not attached to the syringe barrel. Therefore, fear of the patient can be removed.

Moreover, since the cap means for covering the needle is directly in contact with the insertion position, it is not necessary to remove the cap means with one hand, and the injection operation can be properly performed with one hand.

Further, when disposing of the injection needle after use,
Since the cap means is mounted on the needle holding means and the needle is housed inside the cap means, there is no erroneous needle accident.

When the needle is inserted at the insertion position, the cap means slides on the tapered surface of the slide guide with respect to the needle holding means. In other words, as the needle is inserted at the insertion position, the cap means moves from the small-diameter portion to the large-diameter portion on the tapered surface, and the cap means formed by the elastic member so that the diameter can be enlarged is large. As the needle moves to the diameter portion, the fitting with the needle holding means becomes stronger, so that a stable injection can be performed without rattling of the cap means when inserting the needle.

Further, even when the cap means is held at the leading end of the tapered tapered surface of the sliding guide, the retaining means has a radius from the leading end of the tapered surface to the axis. Since it is formed so as to protrude in the direction, there is no possibility that the cap means is locked to the end face of the retaining means and is detached from the needle holding means.

When the needle is inserted, the rear end face of the injection cap passes through a scale formed on the outer peripheral surface of the needle holding member. Can be checked at a glance.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The replacement injection needle (hereinafter, referred to as an injection needle) of the embodiment is configured in a cartridge type so that it can be mounted on a syringe for performing anesthetic injection or injecting medicine. As shown in FIGS. 1 and 2, the injection needle 1 has a needle holding member (needle holding means) 10 through which the needle 3 is inserted on both sides and a distal end side of the needle holding member 10 (rightward in FIG. 1). ), The injection cap (cap means) 20 attached to the needle holding member 10 so as to cover the needle tip 3a, and the needle holding member 1
And a rear protection cap (protection means) 30 attached to the needle holding member 10 so as to cover the base 3b of the needle 3 at the rear end (left side in FIG. 1) of the needle 3. Cap 3
0 is detached and used by mounting it on a syringe barrel 5 as shown in FIG.

As shown in FIG. 2, the needle holding member 10 is formed in a substantially cylindrical shape having a hollow portion 11 at a rear portion and a thick wall portion 12 at a front portion. A small-diameter insertion hole 12a through which the needle 3 is inserted is formed in the core. Also,
The distal end of the wall 12 has a flange portion (prevention means) 13 for preventing the injection cap 20 from being locked out of the needle holding member 10, and a needle behind the flange portion 13. Recess 1 formed on outer peripheral surface of holding member 10
A projecting portion (stopping means) 15 having a tapered portion 15a formed to have a small diameter toward the rear is formed between them. The protrusion 15 is provided at the rear thereof with the injection cap 20.
And the injection cap 20 is attached to the needle holding member 1.
It is prevented from getting out of zero.

A sliding guide 16 is formed at the rear end of the tapered portion 15a. Sliding guide part 1 of the present embodiment
6 is a tapered surface portion 16a connected to the rear end of the tapered portion 15a and formed to have a large diameter toward the rear; and 6 is connected to the rear end of the tapered surface portion 16a and extends to the rear end of the needle holding member 10. And a cylindrical outer peripheral surface portion 16b provided, and the tapered surface portion 16a is formed by a tapered portion 15a of the tapered projection 15.
It is formed in a long shape with a smaller inclination angle.

The connecting portion 18 between the tapered surface portion 16a and the tapered portion 15a of the projection portion 15 is
6a, the collar 23 of the injection cap 20, which will be described later, is held during normal time when injection is not performed, and during injection, the collar 23 is on the tapered surface 16a and the cylindrical outer peripheral surface 16b. Will slide. Therefore,
When the injection needle 1 is not used, a force that slides on the tapered surface portion 16a is not applied to the inner collar portion 23 of the injection cap 20, so that the needle 3 is not exposed without moving the injection cap 20.

A plurality of scales 17 are engraved on the slide guide 16 at regular intervals. When the injection cap 20 is slid, the graduation 17 indicates that the needle
The length of the needle 3 protruding from the tip of the needle 3 can be visually checked by passing the rear end face of the injection cap 20 through the scale 17. This interval may be set as appropriate. For example, if six locations are formed at 5 mm intervals, a projection length of up to 30 mm can be indicated.

A female screw portion 11a is formed on the inner peripheral surface of the rear hollow portion 11, and the male screw portion 5a formed on the syringe barrel 5 is formed.
a.

The sliding guide 16 is formed of the tapered surface 1.
6a and the cylindrical outer peripheral surface 16b, the tapered surface portion may be entirely formed, or the cylindrical outer peripheral surface may be entirely formed. In the latter case, the cylindrical outer surface of the needle holding member 10 and the injection cap 20 are held so that the injection cap 20 can be held by the needle holding member 10.
It is desirable that the fitting is slightly press-fitted so as to have frictional resistance.

The injection cap 20 is, as shown in FIG.
An arc surface portion 21 is formed in a hollow cylindrical shape having a closed front portion and an open rear portion, and has a needle insertion hole 22 through which the needle 3 is inserted at the front end portion. As shown in FIG. 3, a flat portion 21a is formed around the needle insertion hole 22 of the arc surface portion 21 so as to be able to abut on the insertion position of the needle.

Further, an inner flange 23 projecting inward is formed on the opened inner peripheral surface at the rear end of the injection cap 20, and the inner peripheral surface of the inner collar 23 is attached to the needle holding member. The guide surface 24 slidably fitted to the sliding guide portion 16 (tapered surface portion 16a and cylindrical outer peripheral surface portion 16b)
Is formed.

By forming the arcuate surface portion 21 at the tip of the injection cap 20, when the abutment is performed at the position where the injection needle 1 equipped with the injection cylinder 5 is inserted, the patient is rejected without fear. In addition, by providing the flat surface portion 21 on the arc surface portion 21, the position where the needle 3 is inserted is hardly mistaken, and the injection cap 20 is stably held. Can be.

The injection cap 20 is an elastic member (for example, a plastic material) whose diameter can be expanded so that the guide surface 24 slides on the tapered surface portion 16a of the needle holding member 10, and is opaque to hide the needle 3 inside. Needle holding member 10
It is formed so as to be slightly press-fit when externally fitted to the cylindrical outer peripheral surface portion 16b of the sliding guide portion 16 of FIG. Further, a tape material 25 is attached to the arc surface portion 21 at the front end so as to cover the needle insertion hole 22 from the outer surface. If the tape material 25 can be sterilized by inserting the needle 3,
It may be paper or vinyl or other.

Further, the length of the injection cap 20 is such that the guide surface 24 (inner peripheral surface) at the rear end of the injection cap 20 is formed between the projection 15 of the needle holding member 10 and the tapered surface 16a at the time of normal injection. When located at articulation site 18,
The needle cap 3a of the needle 3 protruding from the needle holding member 10 is set in the arc surface portion 21 so that the injection cap 20 can be disposed.
Slides rearward of the needle holding member 10, and the inner flange portion 23 moves.
As shown in FIG. 5, when the rear end face 23a is located at the end of the sliding stroke, the tip 3a of the needle 3 is a predetermined dimension (actually 5 to 30 mm) from the arc surface portion 21 of the injection cap 20.
Degree) It is desirable that the setting is made so as to protrude forward.

The rear protective cap 30 is provided for the injection cap 2
It is desirable to be formed of an elastic member of the same opaque material as 0, and to be closed with a small-diameter projection 31 at the rear end, and to have a cylindrical shape with an opening 32 at the front end. .
The inner peripheral surface 33 of the rear protective cap 30 is
When the injection cap 20 and the rear protection cap 30 are attached to the needle holding member 10 and the two caps 20 and 30 are pulled outward, the rear protection is performed. The cap 30 is set so that it can be easily removed first.

In the following description, the use of the injection needle 1 configured as described above as an anesthetic injection in the treatment of teeth will be described.

First, as shown in FIG.
After removing the rear protective cap 30, the syringe barrel 5 is attached to the rear part of the needle holding member 10 to configure the syringe M. It is possible to use a metal syringe for the syringe barrel 5.
The male screw 5a formed at the distal end of the syringe barrel 5 is preferably connected to the female screw 1 of the needle holding member 10.
1a and screwed together. As shown in FIG. 6, a cartridge-type anesthesia liquid L is housed in the syringe barrel 5 in a state filled in a case, and the injection needle 1 is inserted into the gum T, and then the piston 8 is pushed into the syringe cylinder 5 to perform injection. The anesthetic liquid L in the cylinder 5 is configured to be injected from the needle tip 3a.

A needle holding member 1 is provided at the tip of the syringe barrel 5.
0 is formed with a male screw portion 5a that can be screwed into the female screw portion 11a formed in the rear hollow portion.

Next, when the injection needle 1 is inserted into the gum T in the oral cavity of the patient, as shown in FIG. 6, the patient's mouth is opened and the flat portion 21a of the arc surface portion 21 of the injection cap 20 is removed. Gums T
Abut on the insertion position. In this state, since the needle 3 is hidden in the injection cap 20, the patient cannot see the needle 3. Accordingly, since the patient does not cause a rejection reaction, the syringe M can be smoothly moved to the patient's gum T.

When the syringe 5 is pressed in this state, as shown in FIG.
4 is a projection 15 of the needle holding member 10 and a tapered surface 16a.
From the connection portion 18 along the tapered surface portion 16a and the cylindrical outer peripheral surface portion 16b. When the injection cap 20 moves on the tapered surface portion 16a, the injection cap 20 moves while increasing the diameter of the inner collar portion 23, so that the engagement with the needle holding member 10 gradually becomes stronger. On the other hand, injection cap 2
With the movement of 0, the needle tip 3a is inserted through the needle insertion hole 22 at the tip of the injection cap 20, penetrates the tape material 25, and is inserted into the gum T in the oral cavity. Therefore, in a state where the needle 3 is inserted, the injection cap 20 is firmly fitted to the needle holding member 10, so that the injection cap 20 is stably held.

Moreover, the insertion length of the needle 3 is
When the rear end surface 23a passes through the scale 17 engraved on the outer peripheral surface of the sliding guide portion 16, the doctor who injects can almost certainly confirm the insertion length.

When the needle 3 is inserted, the piston 8 of the syringe M is pushed out to inject the anesthetic L. As shown in FIG. 7, the timing for injecting the anesthetic liquid L may be when the needle tip 3a is inserted into the final position. After the needle tip is inserted little by little, the piston 8 is pushed out to discharge the anesthetic liquid L. A part of the liquid may be injected, and then the remaining liquid may be injected at the position where it has been inserted into the final position. Alternatively, after inserting the needle tip 3a a little, the piston 8 is pushed out until the liquid reaches the final position. You may continue.

In any case, by pressing the flat portion 21a of the arcuate surface portion 21 of the injection cap 20 to the insertion position and pushing out the injection cylinder 5, as shown in FIG. While the diameter of the inner flange portion 23 is increased along the tapered surface portion 16 a and the cylindrical outer peripheral surface portion 16 b of the needle holding member 10, the rear end surface 23 a of the inner collar portion 23 is connected to the front end surface of the injection cylinder 5 (sliding stroke end). ).

A series of operations for moving the syringe M into the oral cavity and pushing out the piston 8 for injecting the anesthetic liquid L is performed when the needle 3 is inserted into the plane portion 21 a of the arc surface portion 21.
And the injection cap 20 is not removed by being held by the needle holding member 10,
All work can be done with one hand.

In addition, when the injection cap 20 is not used, the inner collar 23 is always located at the connecting position 18 between the projection 15 of the needle holding member 10 and the tapered surface 16a. When moving out of the needle holding member 10 by moving to the distal end side from the protruding portion 15, in order to prevent detachment, the inside of the concave portion 14 (see FIG. 2) formed between the flange portion 13 and the protruding portion 15 Collar 23
Is housed and is locked to the end face of the flange portion 13 to prevent double removal.

As shown in FIG. 8, the needle holding member 10 of the injection cap 20 has a tapered surface 16 without the projection 15 as shown in FIG.
0 and the flange portion 130 may be formed so as to be connected. In this case, the outer diameter of the connection portion 180 between the tapered surface portion 160 and the flange portion 130 may be formed to be the same as the outer diameter of the concave portion 14 shown in FIG.

After the use of the injection needle 1, the syringe barrel is removed from the needle holding member 10, and the rear protective cap 30 is
After being mounted on the needle holding member 10 again, it is discarded.

As described above, in the injection needle 1 of the embodiment, the injection cap 20 is formed of an opaque material, and is moved to the insertion position while being attached to the needle holding member 10 so that the injection cylinder 5 of the syringe M is moved. Since the injection cap 20 is configured to be slid to the needle holding member 10 by being pushed out, when the injection is performed on the patient, the needle 3 is moved to the correct insertion position without showing the patient at all. Since the patient can be treated without fear, the patient can smoothly perform treatment without causing rejection.

In addition, since the protrusion 15 or the flange 13 is formed at the tip of the needle holding member 10,
When the injection cap 20 is slidably disposed on the needle holding member 10, the injection cap 20 is
The injection cap 20 is retained by the needle holding member 10 even when the injection needle 1 is not attached to the injection tube 5 or is attached to the injection tube 5 while being locked by the projection 15 or the flange portion 13 of FIG. Since there is no risk of detachment and no exposure of the needle 3, it is difficult to cause fear to the patient.

Further, since the injection cap 20 covering the needle 3 is directly in contact with the insertion position, the injection operation can be performed accurately with one hand without removing the injection cap 20 with one hand.

Further, when disposing of the injection needle 1 after use, the injection cap 20 is attached to the needle holding member 10 and the needle 3 is housed inside the injection cap 20. There is no act of reattaching to the needle holding member 10, and there is no erroneous needle accident that the needle is accidentally stabbed in the hand.

When the needle 3 is inserted at the insertion position, the injection cap 20 slides on the tapered surface 16a of the slide guide 16 with respect to the needle holding member 10. That is, as the needle 3 is inserted at the insertion position, the injection cap 20 moves from the small-diameter portion to the large-diameter portion on the tapered surface portion 16a, and the injection member formed to be expandable by the elastic member. As the cap 20 moves to the large-diameter portion, the fitting with the needle holding member 10 becomes stronger, and when the needle 3 is inserted, the injection cap 20 can perform a stable injection without rattling. Therefore, the doctor can easily perform the injection with one hand.

Further, even when the injection cap 20 is held at the distal end of the tapered tapered surface 16a of the sliding guide 16, the projection 15 or the flange 13 can be connected to the distal end of the tapered surface 16a. The inner cap portion 23 of the injection cap 20 is fitted into the end surface or the concave portion 14 of the projection portion 15 and is locked to the flange surface 13 because it is formed so as to protrude from the portion in the radial direction with respect to the axis. Therefore, there is no possibility that the injection cap 20 is detached from the needle holding member 10.

Since the scale 17 is formed on the needle holding member 10, the insertion length of the needle 3 can be checked at a glance.

The replacement injection needle of the present invention is not limited to the above-described embodiment. For example, as shown in FIGS. 9 to 11, the sliding guide portion 16A of the needle holding member 10A extends from the tapered surface portion 16a to the cylindrical outer peripheral surface portion 16b at one or more locations (two locations in the example) in the circumferential direction. A concave groove 19 parallel to the axis is formed, and the collar 23 of the injection cap 20A is formed.
May be formed as an engaging projection 23A that can be engaged with the concave groove 19. In this form, in a position where the injection cap 20A does not slide, the engagement projection 23A of the injection cap 20A is disposed at a position offset from the concave groove 19 of the needle holding member 10A, and the injection for injection is performed. When the cap 20A is slid, the engagement projection 23A of the injection cap 20A is rotated so as to be aligned with the concave groove 19 of the needle holding member 10A. In this case, the sliding guide 16A may be formed on the outer peripheral surface of the cylinder, and the concave groove may be tapered from the front end surface to the rear end surface.

Further, instead of the rear protective cap 30 which is attached to and detached from the needle holding member 10, a needle protecting part 35 integrally formed with the needle holding member 10 or the injection cap 20 is formed as a protective part for covering the base part 3b of the needle 3. You may make it.
FIG. 12 shows a needle protection portion 35B formed integrally with the needle holding member 10B, and can cover the base 3a of the needle 3 from the rear end of the sliding guide portion 16B of the needle holding member 10B. A needle protection portion 35B for the length is formed in a cylindrical shape and extended so as to fit the distal end portion of the injection cylinder 5 to the outside. Needle protection unit 1
A tape material 36B similar to the tape material 25 attached to the arc surface portion 21 of the injection cap 20 is adhered to the rear end face of 0B. Then, when attaching the needle holding member 10B to the injection cylinder 5, the tape material 36B is peeled off, and the needle holding member 10B is attached so that the distal end portion of the injection cylinder 5 is wrapped by the needle protection portion 35B.

FIG. 13 shows a needle protecting portion 35C integrally formed with the injection cap 20C. The needle holding member 1C is provided behind the inner flange portion 23C of the injection cap 20C.
A needle protection portion 35C of a length that covers OC, the base portion 3a of the needle 3, and the needle holding member 10 is formed in a cylindrical shape so as to fit the distal end portion of the injection cylinder 5 and extends. . Needle protector 35
12, a tape material 36C similar to the tape material 25 attached to the arc surface portion 21 of the injection cap 20 is adhered to the rear end surface of the injection cap 20. And injection cap 2
When attaching the needle holding member 10 holding the OC to the syringe barrel 5, the tape material 36C is peeled off, and the needle holding member 10 is attached so that the tip end of the syringe barrel 5 is wrapped by the needle protection part 35C.

As described above, the protection means for the base of the needle is formed integrally with the needle holding member or the injection cap even if the needle protection portion is detachably mounted on the needle holding member. Even if there is, the effect of protecting the base of the needle can be achieved.

Further, the arc surface portion 21 formed at the distal end portion of the injection cap 20 may not be arc-shaped as in the illustrated example, but may be elliptical. Further, as shown in FIG. 14, when the flat portion 21D formed around the needle insertion hole 22D of the injection cap 20D is disposed at an angle with respect to the insertion position of the injection cap 20D, It may be formed in a flat shape so as to contact the surface at the insertion position.
That is, in the illustrated example, the flat portion 21D is formed along a straight line inclined at a predetermined angle (for example, 30 °) with respect to the axis of the injection cap 20D. According to this embodiment, since the flat portion 22D of the injection cap 20D can reliably contact the insertion position of the gum, the needle 3 is securely inserted at the planned insertion position, and the syringe M is The needle 3 is stably held at the insertion position.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an injection needle according to one embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing the needle holding member in FIG.

FIG. 3 is an enlarged sectional view showing a plane portion of the injection cap in FIG. 1;

FIG. 4 is a cross-sectional view showing a state in which a rear protective cap of the injection needle is removed and attached to a syringe barrel.

FIG. 5 is a cross-sectional view showing a state in which the injection cylinder is pushed out and the needle is inserted through the injection cap.

FIG. 6 is an operation view showing a state in which the tip of the injection cap is in contact with the gum to be injected.

FIG. 7 is an operation view showing a state where a needle is inserted into a gum by a syringe.

FIG. 8 is a sectional view showing another form of the needle holding member.

FIG. 9 is a cross-sectional view showing a connected state of another form of the needle holding member and the injection cap.

FIG. 10 is a sectional view taken along line XX in FIG. 9;

11 is a sectional view taken along line XI-XI in FIG.

FIG. 12 is a cross-sectional view showing a needle protection unit formed integrally with the needle holding member.

FIG. 13 is a cross-sectional view showing a needle protection unit formed integrally with the injection cap.

FIG. 14 is a cross-sectional view showing another form of a plane portion in the arc surface portion of the injection cap.

FIG. 15 is a sectional view showing a conventional injection needle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Injection needle 3 ... Needle 3a ... Needle tip 3b ... Needle base 5 ... Injection cylinder 10 ... Needle holding member 11 ... Female screw part (connection part) 12 ... Wall part (holding wall part) 13 ... Flange part (stop 15) Projecting portion (retaining portion) 16: Sliding guide portion 16a: Tapered surface portion 16b: Cylindrical outer peripheral surface 17: Scale 20: Injection cap 21: Arc surface portion 21a: Flat portion 22: Needle insertion hole 24: Guide surface 30: rear protective cap (protection means) M: syringe

Claims (4)

[Claims] 1. A replacement injection needle configured to be attachable to a syringe barrel of a syringe, comprising: a needle holding means for holding a needle to be inserted; and a needle tip side of the needle at one end of the needle holding means. And a protection means for covering the base side of the needle at the other end of the needle holding means. The cap means is formed opaque and has a needle insertion hole at one end. An arc surface portion is formed, and the needle holding portion has an opening at the other end and is slidably disposed on the needle holding portion, wherein the needle holding portion holds the needle to be inserted, A connecting portion for being attached to the syringe barrel at the base of the needle, a sliding guide portion for sliding the injection cap on the outer peripheral surface, and a distal end of the sliding guide portion; Retaining means for preventing the cap means from being detached from the needle holding means, A replacement injection needle characterized by being formed. 2. The sliding guide portion of the needle holding means,
The needle holding means is formed to have a tapered surface that tapers toward the tip end side, and when the cap means slides along the tapered surface of the sliding guide portion, the opening of the cap means is closed. 2. The replacement injection needle according to claim 1, wherein the replacement injection needle is formed of an elastic member capable of expanding the diameter. 3. The device according to claim 1, wherein the retaining means is formed so as to protrude from an outer peripheral surface of a distal end of the sliding guide portion in a radial direction with respect to an axis of the needle holding means. Or the replacement needle according to 2. 4. The replacement injection needle according to claim 1, wherein a scale indicating a length of the needle protruding from the injection cap is formed on an outer peripheral surface of the needle holding member.