WO2012147415A1

WO2012147415A1 - Injection needle assembly and drug injection device

Info

Publication number: WO2012147415A1
Application number: PCT/JP2012/055938
Authority: WO
Inventors: 小川　淳一; 陽一郎岩瀬; 立川　浩一
Original assignee: テルモ株式会社
Priority date: 2011-04-28
Filing date: 2012-03-08
Publication date: 2012-11-01

Abstract

The present invention provides an injection needle assembly that can be attached to a syringe from which air has been purged, and a drug injection device that uses the injection needle assembly. This injection needle assembly (100) has a reservoir hole (32a) that communicates with a needle hole (31a) of a needle body (31) in a needle tube (3), and forms an injection needle assembly (1) with a reservoir part (32) where the volume of an internal space is 20 µL or higher. The drug injection device (100) is made by attaching a syringe (2), in a state in which air has been purged from the inside, the syringe being filled with a drug (80) and having a discharge part (42) for discharging the drug (80).

Description

Injection needle assembly and drug injection device

The present invention relates to an injection needle assembly and a drug injection device in which a syringe in which a drug is contained and an air vent is performed can be attached.

In recent years, prefilled syringes in which a medicine is prefilled in a syringe are often used. Such a prefilled syringe does not require an operation of sucking the drug from the vial into the syringe at the time of drug administration, and thus it is possible to reduce the time required for drug administration.

For example, the following Patent Document 1 discloses a prefilled syringe including a syringe body filled with a medicine and a cap attached to the syringe body and sealing the medicine in the syringe body.

When using such a prefilled syringe, a needle hub to which the injection needle is fixed is attached to the medicine discharge portion which is the tip of the prefilled syringe, and the proximal end of the injection needle is communicated with the inside of the syringe body. And a chemical | medical agent is discharged | emitted from the needle point of an injection needle by pressing the pusher provided in the syringe main body.

In the syringe using the prefilled syringe, as described above, it is not necessary to suck the drug from the vial, so that it is possible to reduce the time required for the drug administration.
However, in order to administer, the operation | work which attaches the syringe filled with the chemical | medical agent to the needle hub prepared separately, and the operation | work which performs what is called air bleeding which discharges | emits the air in a syringe are required.

In addition, in the injection needle assembly disclosed in Patent Document 2 below, a skin contact portion capable of adjusting the depth of puncture of the injection needle is provided in order to perform stable puncture. In this injection needle assembly, if the air is vented after the syringe is attached to the needle hub, the liquid droplet leaks from the tip of the injection needle, and the chemical adheres between the skin contact portion and the skin contact portion and the needle tube. There is a fear. For this reason, it is also conceivable to vent the syringe before attaching the syringe to the needle hub.

JP 2004-321826 A JP 2000-037456 A

However, even if the syringe is bleed before the syringe is attached to the needle hub, when the evacuated syringe is attached to the needle hub, the drug accumulated in the syringe discharge part is discharged from the tip through the injection needle. May be.

The present invention has been made in view of the above points, and an object of the present invention is to provide an injection needle assembly to which a syringe that has been evacuated can be attached, and a medicine injection device using the injection needle assembly.

In order to solve the above-described problems, an injection needle assembly according to the present invention includes a needle body having a needle tip that is pierced into the skin and a proximal end opposite to the needle tip, and a proximal end of the needle body. And a reservoir having a reservoir hole communicating with the needle hole of the needle body.
Also, it has a medicine filled inside and a discharge part for discharging the medicine, a fitting part into which a discharge part of a syringe in a state where air is discharged from the inside is inserted, a needle tube holding the needle tube, A needle hub having a holding portion for positioning the storage portion at the insertion portion.
And the capacity | capacitance of the space in a storage part shall be 20 microliters or more.

Further, another injection needle assembly according to the present invention has a needle tip punctured into the skin, a needle tube having a proximal end opposite to the needle tip, and a storage hole communicating with the needle hole of the needle tube. A reservoir connected to the proximal end.
Also, it has a medicine filled inside and a discharge part for discharging the medicine, a fitting part into which a discharge part of a syringe in a state where air is discharged from the inside is inserted, a needle tube holding the needle tube, A needle hub having a holding portion for positioning the storage portion at the insertion portion.
And the capacity | capacitance of the space in a storage part shall be 20 microliters or more.

The drug injection device according to the present invention includes a drug filled inside and a discharge part for discharging the drug, and a syringe from which air is discharged is attached to the above-described injection needle assembly. is there.

According to the injection needle assembly and the drug injection device of the present invention, the drug can be stored in the storage part by providing the storage part in the needle tube. For this reason, even if it attaches the syringe which performed air bleeding previously, it can prevent that a chemical | medical agent leaks from a needle point.

According to the injection needle assembly and the drug injection device of the present invention, it is possible to suppress the formation of liquid droplets at the needle tip of the needle tube, so that a syringe filled with the drug and exhausted air is attached in advance. Is possible. For this reason, the operation | work which discharges the air in a syringe after attaching to a needle hub can be reduced, and it can suppress that a chemical | medical agent adheres to the circumference | surroundings.

It is an exploded view showing the composition of the medicine injection device concerning a 1st embodiment of the present invention. It is sectional drawing which shows the structure of the chemical injection device which concerns on the 1st Embodiment of this invention. It is explanatory drawing which shows the state which a chemical | medical agent leaks from the needle point of a needle tube. It is an enlarged view showing the medicine injection device concerning a 1st embodiment of the present invention. It is an enlarged view showing the medicine injection device concerning a 1st embodiment of the present invention. It is sectional drawing which shows the structure of the chemical injection apparatus which concerns on the 2nd Embodiment of this invention.

Examples of modes for carrying out the present invention will be described below, but the present invention is not limited to the following examples. The description will be made in the following order.
1. 1st Embodiment (The example which makes the diameter of the proximal end of a needle tube thick and uses it as a storage part)
2. 2nd Embodiment (example which connects a storage part as another member to the base end of a needle tube)

1. 1st Embodiment (The example which makes the diameter of the proximal end of a needle tube thick and uses it as a storage part)
FIG. 1 is an exploded view of a drug injection device 100 according to the present embodiment.
The drug injection device 100 is used when the needle tip is punctured from the surface of the skin and, for example, the drug is injected into the upper layer of the skin. As shown in FIG. 1, the drug injection device 100 includes an injection needle assembly 1 and a syringe 2 connected to the injection needle assembly 1 and filled with a drug (medicine solution).

[Injection needle assembly]
The injection needle assembly 1 includes a hollow needle tube 3 having a needle hole, a needle hub 4 to which the needle tube 3 is fixed, an elastic member 7 disposed in the needle hub 4, and a detachable attachment to the needle hub 4. And a cap 5 for protecting the needle tube 3. The needle hub 4 includes a first member 6 as a holding portion for holding the needle tube 3 and a second member 8 into which a later-described discharge portion 42 of the syringe 2 is fitted.

The needle tube 3 of the injection needle assembly 1 includes a needle body 31 having a needle tip 3A that is punctured into the skin, and a storage portion 32 that is continuous with the proximal end 3B of the needle body 31 opposite to the needle tip 3A. .
The needle body 31 of the needle tube 3 has a size of 26 to 33 gauge (outer diameter 0.2 to 0.45 mm) according to the ISO medical needle tube standard (ISO9626: 1991 / Amd.1: 2001 (E)), and more 30 to 33 gauge is preferable.

FIG. 2 is a cross-sectional view showing a state in which the syringe 2, the needle tube 3, and the needle hub 4 are assembled.
As shown in FIG. 2, a needle tip 3 A having a blade surface 3 a is provided at one end of the needle main body 31 of the needle tube 3. The axial length of the needle body 31 on the blade surface 3a (hereinafter referred to as “bevel length”) may be 1.4 mm (adult) or less, which is the thinnest thickness of the upper skin layer described later. The bevel length may be about 0.5 mm or more when a short bevel is formed on a 33 gauge needle tube. That is, the bevel length is preferably set in the range of 0.5 to 1.4 mm.

Further, the bevel length is further preferably such that the thinnest thickness of the upper skin layer is 0.9 mm (child) or less, that is, the bevel length is in the range of 0.5 to 0.9 mm. The short bevel refers to a blade surface that is generally used for injection needles and forms an angle of 18 to 25 ° with respect to the longitudinal direction of the needle.

Examples of the material of the needle tube 3 include stainless steel, but are not limited thereto, and aluminum, aluminum alloy, titanium, titanium alloy, and other metals can be used.
Further, the cross-sectional shape of the needle tube 3 may be not only a circle but also a polygon such as a triangle.

Next, the needle hub 4 will be described.
The first member 6 and the second member 8 of the needle hub 4 are formed as separate members, but may be formed integrally. Examples of the material of the first member 6 and the second member 8 include synthetic resins such as polycarbonate, polypropylene, and polyethylene.

The first member 6 that holds the needle tube 3 in the needle body 31 includes a base portion 9, an adjustment portion 10, a stabilization portion 11, and a guide portion 12. The base portion 9 is formed in a substantially cylindrical shape and has end faces 9a and 9b perpendicular to the axial direction. The adjustment unit 10 is provided at the center of the end surface 9 a of the base unit 9, and includes a columnar projection that protrudes in the axial direction of the base unit 9. The axis of the adjustment unit 10 is coincident with the axis of the base unit 9.

A through hole 13 through which the needle body 31 of the needle tube 3 passes is provided in the axial center of the base portion 9 and the adjusting portion 10. The base portion 9 is provided with an injection hole 15 for injecting the adhesive 14 into the through hole 13. The injection hole 15 is opened on the outer peripheral surface of the base portion 9 and communicates with the through hole 13. That is, the needle tube 3 is fixed to the base portion 9 by the adhesive 14 injected from the injection hole 15 to the through hole 13.

The proximal end 3B side of the needle body 31 protrudes from the end surface 9b of the base portion 9. The base portion 9 is inserted into the second member 8 from the end surface 9b side, and the needle tube 3 is inserted from a needle tip 3A side of the needle body 31 into a through-hole 73a described later of the elastic member 7. And the end surface 9b of the base part 9 is contact | abutted to the end surface 70a which the elastic member 7 mentions later.

A connecting piece 16 is provided on the outer peripheral surface of the base portion 9. The connection piece 16 is formed as a ring-shaped flange projecting in the radial direction of the base portion 9, and has

flat surfaces

16 a and 16 b facing the axial direction of the base portion 9. The second member 8 is connected to the flat surface 16 b of the connection piece 16. Further, the distal end portion of the connection piece 16 is a guide portion 12.

The end surface of the adjusting portion 10 is a needle protruding surface 10a from which the needle tip 3A side of the needle tube 3 protrudes. The needle projecting surface 10 a is formed as a plane orthogonal to the axial direction of the needle tube 3. The needle protruding surface 10a defines the depth of puncturing the needle tube 3 in contact with the skin surface when the needle tube 3 is punctured into the upper skin portion. That is, the depth at which the needle tube 3 is punctured into the upper skin layer is determined by the length of the needle tube 3 protruding from the needle protruding surface 10a (hereinafter referred to as “projection length L”).

The thickness of the upper skin portion corresponds to the depth from the skin surface to the dermis layer, and is generally in the range of 0.5 to 3.0 mm. Therefore, the protruding length L of the needle tube 3 can be set in the range of 0.5 to 3.0 mm.

By the way, the vaccine is generally administered to the upper arm, but in the case of administration to the upper skin part, the shoulder peripheral part where the skin is thick, particularly the deltoid part is preferable. According to the results of measuring the thickness of the upper layer of the deltoid muscle for 19 children and 31 adults, the thickness of the upper layer of the skin of the deltoid muscle is 0.9 mm or more for children and 1.4 mm for adults. That was confirmed. Therefore, in the injection at the upper layer portion of the deltoid skin, the protruding length L of the needle tube 3 is preferably set in the range of 0.9 to 1.4 mm.

By setting the protruding length L in this way, the blade surface 3a of the needle tip 3A can be reliably positioned on the upper skin portion. As a result, the needle hole (medicine discharge port) that opens in the blade surface 3a can be located in the upper skin layer portion at any position within the blade surface 3a. Even if the medicine discharge port is located in the upper skin layer, if the needle tip 3A is stabbed deeper than the upper skin layer, the medicine flows subcutaneously between the side surface of the end of the needle tip 3A and the cut skin. Therefore, it is important that the blade surface 3a is surely in the upper skin portion.

Note that it is difficult to make the bevel length 1.0 mm or less with a needle tube thicker than 26 gauge. Therefore, in order to set the protruding length L of the needle tube 3 within a preferable range (0.9 to 1.4 mm), it is preferable that the diameter of the needle body 31 is smaller than 26 gauge.

The needle projecting surface 10a is formed such that the distance S from the peripheral edge to the outer peripheral surface of the needle tube 3 is 1.4 mm or less, preferably in the range of 0.3 to 1.4 mm. By setting in this way, formation of blisters caused by administration of the drug to the upper skin layer is not hindered. That is, even if the needle protruding surface 10a presses the skin around the needle tube 3, it is possible to prevent the administered medicine from leaking.

The stabilizing part 11 is formed in a cylindrical shape protruding from the flat surface 16 a of the connecting piece 16 provided on the base part 9. The needle body 31 and the adjustment unit 10 of the needle tube 3 are disposed in the cylindrical hole of the stabilization unit 11. That is, the stabilizing portion 11 is formed in a cylindrical shape that covers the periphery of the adjusting portion 10 through which the needle body 31 passes, and is provided away from the needle tip 3A of the needle body 31 in the radial direction.

2, the end surface 11a of the stabilizing portion 11 is located closer to the proximal end 3B side of the needle tube 3 than the needle protruding surface 10a of the adjusting portion 10. When the living body is punctured with the needle tip 3 A of the needle tube 3, first, the needle protruding surface 10 a contacts the surface of the skin, and then contacts the end surface 11 a of the stabilizing portion 11. At this time, the drug injection device 100 is stabilized by the end surface 11a of the stabilizing portion 11 coming into contact with the skin, and the needle tube 3 can be maintained in a posture substantially perpendicular to the skin.

The stabilizing portion 11 is formed with a first vent hole 17 penetrating from the outer peripheral surface to the inner peripheral surface. By providing the first ventilation hole 17 in the stable portion 11, when the stable portion 11 is brought into contact with the skin, a space surrounded by the stable portion 11 and the skin and a space outside the stable portion 11 are separated. Can communicate.
The adjustment portion 10 is also provided with a second ventilation hole 18 that penetrates the side surface thereof and communicates with the through hole 13. The first ventilation hole 17 and the second ventilation hole 18 constitute a space surrounded by the stabilizing portion 11 and the skin and a ventilation means for opening the through hole 13 to the outside.

Even if the end surface 11a of the stabilizing portion 11 is located on the same plane as the needle projecting surface 10a, or is located closer to the needle tip 3A side of the needle tube 3 than the needle projecting surface 10a, the needle tube 3 is skinned. It is possible to keep the posture substantially perpendicular to the angle. In consideration of the swelling of the skin when the stable portion 11 is pressed against the skin, the axial distance between the end surface 11a of the stable portion 11 and the needle protruding surface 10a is preferably set to 1.3 mm or less.

Further, the inner diameter d of the stable portion 11 is set to a value equal to or larger than the diameter of the blister formed on the skin. By setting the distance T from the inner wall surface of the stable portion 11 to the peripheral edge of the needle protruding surface 10a to be in the range of 4 mm to 15 mm, it is possible to avoid the inhibition of blister formation.

The distance T from the inner wall surface of the stable portion 11 to the peripheral edge of the needle protruding surface 10a is not particularly limited as long as it is 4 mm or more. However, when the distance T is increased, the outer diameter of the stable portion 11 is increased, so that it becomes difficult to bring the entire end surface 11a of the stable portion 11 into contact with the skin when the needle tube 3 is punctured into a thin arm like a child. . For this reason, the distance T is preferably set to 15 mm as a maximum in consideration of the thinness of the child's arm.

If the distance S from the peripheral edge of the needle protruding surface 10a to the outer peripheral surface of the needle tube 3 is 0.3 mm or more, the adjusting unit 10 does not enter the skin. Therefore, considering the distance T (4 mm or more) from the inner wall surface of the stable portion 11 to the periphery of the needle protruding surface 10a and the diameter (about 0.3 mm) of the needle protruding surface 10a, the inner diameter d of the stable portion 11 is 9 mm or more. It is preferably set.

In addition, the shape of the stable part 11 is not limited to a cylindrical shape, and may be formed in a rectangular tube shape such as a quadrangular column or a hexagonal column having a cylindrical hole at the center.

The guide portion 12 is a portion on the peripheral side with respect to the position of the stable portion 11 in the connection piece 16. The guide portion 12 has a contact surface 12a that comes into contact with the skin. The contact surface 12 a is a part of the flat surface 16 a of the connection piece 16 and is a flat surface that is substantially parallel to the end surface 11 a of the stabilizing portion 11. By pressing the stable portion 11 until the contact surface 12a of the guide portion 12 comes into contact with the skin, the force with which the stable portion 11 and the needle tube 3 press the skin can always be secured to a predetermined value or more.

The distance Y from the contact surface 12a of the guide portion 12 to the end surface 11a of the stable portion 11 (hereinafter referred to as “guide portion height”) Y punctures the needle tube 3 and the stable portion 11 by pressing the skin with an appropriate pressing force. Its length is set so that it can. An appropriate pressing force of the needle tube 3 and the stable portion 11 is, for example, 3 to 20N.

When the range of the inner diameter d of the stable portion 11 is 11 to 14 mm, the guide portion height Y is the length from the tip surface of the guide portion 12 to the outer peripheral surface of the stable portion 11 (hereinafter referred to as “guide portion length”). It is determined appropriately based on X. For example, when the inner diameter d of the stable portion 11 is 12 mm and the guide portion length X is 3.0 mm, the guide portion height Y is set in the range of 2.3 to 6.6 mm.

The cap 5 (see FIG. 1) is detachably fitted to the guide portion 12. The cap 5 covers the needle tip 3 A of the needle body 31. Thereby, when attaching needle hub 4 to syringe 2, it can prevent needle tip 3A touching a user's fingertip. In addition, the used medicine injection device 100 or the needle assembly 1 can be always kept in a safe state, and the user can safely dispose of the used medicine injection device 100 or the needle assembly 1 or the like. It can be carried out.

Next, the second member 8 will be described. The second member 8 is formed in a substantially cylindrical shape. One end portion of the second member 8 in the axial direction is an insertion portion 19 into which the base portion 9 of the first member 6 is inserted, and the other end portion is in the insertion portion 20 into which the discharge portion 42 of the syringe 2 is inserted. It has become. The cylindrical hole 19 a of the insertion portion 19 is set to a size corresponding to the base portion 9 of the first member 6.

The insertion part 19 is provided with a fixing piece 21 connected to the connection piece 16 of the first member 6. The fixed piece 21 is formed as a ring-shaped flange that protrudes radially outward continuously from the tip of the fitting portion 20. A flat surface 16 b of the connection piece 16 provided on the first member 6 is brought into contact with and fixed to the fixed piece 21. Examples of the fixing method of the fixing piece 21 and the connection piece 16 include an adhesive, ultrasonic welding, laser welding, and a fixing screw.

The cylinder hole 20a of the insertion part 20 is set to a size corresponding to the discharge part 42 of the syringe 2, and the diameter continuously decreases toward the insertion part 19 side. A thread groove 22 for screwing the discharge part 42 of the syringe 2 is formed on the inner surface of the fitting part 20.

Further, on the inner surface of the fitting portion 20, a stopper 23 that protrudes toward the axis of the cylindrical hole 20 a is provided closer to the insertion portion 19 than the screw groove 22. When the syringe 2 is inserted into the insertion portion 20, the discharge portion 42 of the syringe 2 is locked by the stopper 23, thereby preventing further insertion of the syringe 2.
Thus, a gap is provided in the axial direction of the cylindrical hole 20 a between the end surface 42 a of the discharge portion 42 and the storage portion 32 of the needle tube 3.

Further, as shown in FIG. 1, a hub side display unit 25 may be provided on the outer peripheral surface of the insertion unit 20 as a recognition unit for recognizing that the insertion of the discharge unit 42 is completed. When the discharge part 42 is inserted into the insertion part 20, the hub side display part 25 coincides with a syringe side display part 44 (described later) provided in the discharge part 42 in the circumferential direction of the second member 8. Thereby, it can be made to recognize that the insertion to the insertion part 20 of the discharge part 42 was completed. Therefore, in the present embodiment, at least the second member 8 of the needle hub 4 is formed of a transparent or translucent synthetic resin so that the syringe-side display portion 44 can be visually recognized through the fitting portion 20.

In addition, as a recognition part which concerns on this invention, a convex part is provided in one base end of the thread part 43 of the syringe 2 or the thread groove 22 of the insertion part 20, and the recessed part engaged with the convex part is made into the other base end. You may form by providing. In this case, it is possible to recognize that the insertion of the discharge portion 42 into the insertion portion 20 is completed by the engagement between the convex portion and the concave portion.

Between the insertion part 19 and the insertion part 20, the engaging part 24 with which the elastic member 7 engages is provided. The engaging portion 24 is formed as a step portion protruding radially inward from the inner surface of the second member 8, and has engaging

surfaces

24 a and 24 b that are substantially orthogonal to the axial direction of the second member 8. . A first flange portion 71 described later of the elastic member 7 is engaged with the engagement surface 24a of the engagement portion 24, and a second flange portion 72 of the elastic member 7 is engaged with the engagement surface 24b. The

The elastic member 7 is disposed in the second member 8 of the needle hub 4 and is interposed between the first member 6 that holds the needle tube 3 and the syringe 2. The elastic member 7 has a main body portion 70, a first flange portion 71 provided at one end of the main body portion 70 in the axial direction, and a second flange portion 72 provided at the other end of the main body portion 70. is doing.

The main body 70 is formed in a substantially cylindrical shape and has end faces 70a and 70b perpendicular to the axial direction. The end surface 9 b of the base portion 9 of the first member 6 is in contact with the end surface 70 a of the main body portion 70. Moreover, the end surface 70b of the main-body part 70 is spaced apart from the end surface 42a of the discharge | emission part 42 of the syringe 2, and the space | gap exists between them.

The main body portion 70 is provided with an insertion hole 73 through which the needle tube 3 is inserted. The insertion hole 73 is formed in the axial direction of the needle tube 3 and is opened in the end faces 70a and 70b.
The insertion hole 73 includes a through hole 73a through which the needle body 31 of the needle tube 3 passes and an embedding hole 73b in which a part of the storage portion 32 of the needle tube 3 is embedded. The through hole 73a and the embedding hole 73b communicate with each other in the axial direction of the needle tube 3, and the diameter of the embedding hole 73b is set larger than the diameter of the through hole 73a.

The first flange portion 71 is formed in a ring shape that protrudes radially outward from the outer peripheral surface of the main body portion 70. The outer diameter of the first flange portion 71 is substantially equal to the outer diameter of the base portion 9 of the first member 6. The elastic member 7 is attached to the needle hub 4 by holding the first flange portion 71 between the engaging portion 24 of the second member 8 and the base portion 9 of the first member 6.

The second flange portion 72 is formed in a ring shape that protrudes radially outward from the outer peripheral surface of the main body portion 70, similarly to the first flange portion 71. The second flange portion 72 engages with the engagement surface 24 b of the engagement portion 24 provided on the second member 8. The elastic member 7 is locked to move in the axial direction by the first flange portion 71 and the second flange portion 72 engaging the engaging portion 24 of the second member 8. Thereby, it can prevent that a chemical | medical agent permeates between the elastic member 7 and the 2nd member 8, and leaks to the 1st member 6 side, and can improve a pressure | voltage resistant performance.

Examples of the material of the elastic member 7 include various rubber materials such as natural rubber, silicone rubber, and isobutylene rubber, various thermoplastic elastomers such as polyurethane and styrene, or mixtures thereof.

[Syringe]
The syringe 2 includes a syringe body 41 and a discharge portion 42 that is continuous with the syringe body 41. The syringe body 41 is formed of a circular cylinder. The discharge part 42 protrudes from one end of the syringe body 41 in the axial direction, and is composed of a circular cylinder having an outer diameter smaller than that of the syringe body 41. The discharge portion 42 is formed in a tapered shape whose diameter continuously decreases toward the tip.

For example, the end surface 42 a that is the tip of the discharge portion 42 abuts against a stopper 23 provided on the inner wall surface of the second member 8, thereby limiting the insertion depth of the syringe 2 with respect to the needle hub 4. Thereby, a gap is provided between the end face 42 a and the proximal end 3 B of the needle tube 3 in the axial direction of the needle tube 3.
In addition, as shown in FIG. 2, the insertion depth of the syringe 2 may be limited by the end surface 41 a of the syringe main body 41 coming into contact with the distal end of the insertion portion 20 of the second member 8, and the end surface 42 a and the needle tube 3 may be limited. Other configurations may be used as long as a predetermined gap is provided between the base ends 3B.

As shown in FIG. 1, the outer peripheral surface of the discharge portion 42 is provided with a screw portion 43 for screwing onto the second member 8 of the needle hub 4 and a syringe-side display portion 44. The syringe-side display unit 44 is recognized via the second member 8 of the needle hub 4 when the discharge unit 42 is inserted into the insertion unit 20 provided in the needle hub 4. And when the discharge part 42 contacts the engaging part 24 of the insertion part 20 and the insertion is completed, the syringe side display part 44 coincides with the hub side display part 25 of the needle hub 4 in the circumferential direction.

In the syringe body 41, a gasket (not shown) is accommodated. The space in the syringe body 41 is liquid-tightly partitioned by a gasket, and one space communicating with the discharge part 42 forms a liquid chamber 46 together with the space in the discharge part 42. In the other space in the syringe body 41, a plunger (not shown) is arranged. The plunger is connected to the gasket and protrudes from the opening at the other end of the syringe body 41. By operating this plunger, the gasket is moved in the axial direction in the syringe body 41, and the medicine filled in the syringe body 41 is discharged.

Further, the syringe 2 is vented after the medicine (chemical solution) 80 is filled, and the air in the liquid chamber 46 is discharged in advance. In this case, in particular, in order to prevent air from remaining in the liquid chamber 46, the liquid chamber 46 is filled with an amount of medicine 80 slightly larger than the volume of the liquid chamber 46, and the droplet 81 is discharged from the discharge port 42b. It is desirable to form it.
As a material of the syringe main body 41 and the discharge part 42, synthetic resins such as polycarbonate, polypropylene, and polyethylene can be used, and glass or the like may be used.

Moreover, in this Embodiment, the space | gap is provided between the storage part 32 of the needle tube 3, and the end surface 42a of the discharge part 42 of the syringe 2. As shown in FIG. A discharge port 42 b is opened in the discharge part 42 of the syringe 2, and the syringe 2 is inserted into the insertion part 20 in a state where the internal space communicates with the internal space of the insertion part 20.
By providing this gap, even when the droplet 81 is formed at the discharge port 42 b of the discharge portion 42 of the syringe 2, it is possible to suppress the droplet 81 from contacting the storage portion 32 of the needle tube 3.

As described above, in the drug injection device 100 of the present embodiment, the syringe 2 filled with the drug 80 is attached to the needle hub 4 in advance in order to enable rapid drug administration to the patient. When the syringe and the needle hub are stored separately and assembled just before use, a sealing member for sealing the internal medicine is provided at the discharge port of the syringe. However, in this embodiment, if the medicine injection device 100 is taken out, the discharge port 42b and the internal space of the needle hub 4 are communicated from the beginning so that the medicine can be administered as it is.

Further, as described above, in the present embodiment, since the syringe 2 that has been filled with the medicine 80 in advance and evacuated is attached to the needle hub 4, a droplet of the medicine 80 is placed in the discharge port 42 b of the syringe 2. 81 is formed. Even if the air is not vented, the droplet 81 may be formed by the weight of the medicine 80.

For example, FIG. 3 shows a drug injection device 110 configured to bring the discharge portion 42 of the syringe 2 into contact with the elastic member 7 with respect to the drug injection device 100 according to the present embodiment as a comparative example.
It should be noted that parts corresponding to those of the drug injection device 100 (FIG. 2) according to the present embodiment are denoted by the same reference numerals as those in FIG.

In the medicine injection device 110 shown in FIG. 3, the stopper is not provided on the wall surface of the cylindrical hole 20 a in the fitting portion 20 of the second member 8. The discharge part 42 of the syringe 2 inserted into the insertion part 20 is in contact with the elastic member 7, and is in liquid-tight contact with the end surface 70 b of the elastic member 7 at the end surface 42 a of the discharge part 42.
Further, the needle tube 3 is constituted only by the needle main body 31 in FIG. 2, and does not have the storage portion 32 in FIG.

In this case, as shown in FIG. 3, the droplet 81 formed on the discharge part 42 of the syringe 2 has come into contact with the proximal end 3 B of the needle tube 3.
When the droplet 81 comes into contact with the proximal end 3B of the needle tube 3, the drug 80 in the syringe 2 enters the inside of the needle tube 3, and the drug 80 slightly leaks from the needle tip 3A of the needle tube 3, so that the droplet 82 is formed. May be formed.

For example, in general, when a syringe is attached to a needle hub, it is necessary to fit in a liquid-tight manner so that liquid leakage does not occur at a fitting portion between the syringe and the needle hub. For this reason, in the

medicine injection devices

100 and 110 shown in FIG. 1 and FIG. 3, the discharge portion 42 is made fluid-tight to the fitting portion 20 by bringing the outer wall surface of the discharge portion 42 into surface contact with the inner wall surface of the cylindrical hole 20a. It is inserted. Therefore, when the discharge portion 42 is fitted, the internal space of the cylindrical hole 20a between the end surface 42a of the discharge portion 42 and the end surface 70a of the elastic member 7 is airtight to some extent.
For this reason, if the discharge part 42 of the syringe 2 is inserted in the insertion part 20, the gas in the cylinder hole 20a will be compressed and atmospheric pressure will rise. Therefore, when the droplet 81 comes into contact with the proximal end 3B of the needle tube 3 as shown in FIG. 3, the drug 80 is pushed out into the needle tube 3 by this atmospheric pressure, and the drug 80 leaks from the needle tip 3A.

If such a liquid leak occurs, there is a risk that when the drug injection device 110 is taken out at the time of administration, the liquid droplets fall and cause chemicals to adhere to the surroundings. In addition, when the injection is performed with the liquid droplet attached to the needle tip and the liquid droplet adheres to the patient's skin, there is a risk that the patient may feel uncomfortable.

On the other hand, in the medicine injection device 100 according to the present embodiment, as shown in FIG. 2, the storage portion 32 is provided on the proximal end 3 B side of the needle body 31. By providing this storage part 32, the volume of the space in the needle tube 3 is increased. Thereby, even if the droplet 81 comes into contact with the storage portion 32, it is possible to prevent the medicine 80 from leaking from the needle tip 3 A of the needle tube 3.

FIG. 4 is an enlarged view in which the vicinity of the storage portion 32 is enlarged. The reservoir 32 is formed continuously with the proximal end 3B of the needle body 31. The storage portion 32 is provided with a storage hole 32 a that forms an opening of the needle tube 3, and the storage hole 32 a communicates with the needle hole 31 a of the needle body 31. Further, the axis of the needle hole 31a and the axis of the storage hole 32a coincide.
The diameter of the storage hole 32a is larger than the diameter of the needle hole 31a, and the capacity of the storage hole 32a is greater than or equal to the amount by which the droplet falls by its own weight from the discharge part 42 of the syringe 2, specifically 20 μL or more and 40 μL or less. Is preferred.

Further, the storage hole 32a has a tapered shape that becomes thicker from the proximal end 3B of the needle body 31 toward the droplet 81 side. By making it taper shape, it becomes easy to insert the storage part 32 in the embedding hole 73b of the elastic member 7. FIG. Further, by increasing the diameter of the storage unit 32 on the droplet 81 side, the storage unit 32 can be tightly adhered to the elastic member 7 and the pressure resistance performance can be improved.

Further, in the present embodiment, the storage portion 32 is molded integrally with the needle body 31. For example, a so-called tapered needle can be used as the needle tube 3 provided with the storage portion 32.

In addition, if the storage part 32 is completely buried inside the elastic member 7, the elastic member 7 may be pressed and deformed during the administration of the medicine 80, and the storage hole 32a may be blocked. For this reason, in this Embodiment, a part of storage part 32 is made to protrude from the end surface 70b of the elastic member 7. FIG. Moreover, the dead volume between the discharge part 42 and the elastic member 7 can be reduced by the volume of the storage part 32 protruding from the end face 70b of the elastic member 7.

FIG. 5 is an explanatory diagram showing a state in which the droplet 81 is in contact with the storage unit 32.
When the droplet 81 comes into contact with the storage portion 32, the storage hole 32 a, that is, the opening of the needle tube 3 is closed by the droplet 81 and is in a sealed state.
When the medicine 80 enters the inside of the needle tube 3 from this state, the air in the needle tube 3 is discharged from the needle tip 3A (not shown) by the volume of the medicine 80 that has entered.

Therefore, when the storage hole 32 a of the storage portion 32 is filled with the medicine 80, air corresponding to the volume of the storage hole 32 a is discharged from the needle tip 3 A of the needle tube 3. When the medicine 80 enters the needle hole 31a of the needle body 31 from the storage hole 32a and the needle hole 31a is filled with the medicine 80, air corresponding to the volume of the needle hole 31a is discharged from the needle tip 3A of the needle tube 3. The
That is, the medicine 80 does not leak from the needle tip 3A unless the volume of the storage hole 32a and the air of the volume of the needle hole 31a of the needle body 31 are discharged.
From this, it can be seen that if the internal volume of the needle tube 3 is increased, the medicine 80 can be retained inside the needle tube 3 by the increased volume.

Therefore, even if the droplet 81 is pressed by compressing the air in the fitting portion 20 and the droplet 81 enters the inside of the needle tube 3, the storage portion 32 is provided as in the present embodiment to provide the needle tube. By increasing the internal capacity of 3, the medicine 80 can be retained inside the needle tube 3. Thereby, it can control that medicine 80 leaks from needle tip 3A.

In the present embodiment, the state in which the droplet 81 contacts the storage portion 32 and seals the opening of the storage hole 32a is described. The storage portion 32 is caused by the medicine 80 from the discharge portion 42 side. It will be satisfied.
However, when the droplet 81 does not seal the opening of the storage hole 32 a, the medicine 80 flows along the inner surface of the storage portion 32, and the medicine 80 is filled with the needle before the storage portion 32 is filled with the medicine 80. There is a risk of reaching the needle hole 31 a of the main body 31. Then, the air in the storage part 32 cannot be discharged from the needle tip 3A before the medicine 80. Therefore, it is preferable that the opening of the storage hole 32 a is sealed with the droplet 81 when the droplet 81 comes into contact with the storage portion 32.
For this reason, in this embodiment, the diameter of the opening of the storage hole 32 a is set smaller than the diameter of the droplet 81. Further, since the diameter of the droplet 81 is at least larger than the diameter of the discharge port 42b of the discharge unit 42, it is more certain that the diameter of the storage hole 32a is smaller than that of the discharge port 42b.

As described above, in this embodiment, even when the syringe 2 filled with the medicine 80 and previously vented is attached to the needle hub 4, no droplet is formed on the needle tip 3A. For this reason, it becomes possible to attach the syringe 2 filled with the medicine 80 and evacuated to the injection needle assembly 1 in advance, and the work of discharging the air in the syringe can be reduced. Further, since no droplet is formed on the needle tip 3A, it is possible to prevent chemicals from adhering to the surroundings.

2. 2nd Embodiment (example which connects a storage part as another member to the base end of a needle tube)
In the first embodiment, the needle body 31 and the storage portion 32 are integrally molded to form the needle tube 3, but the storage portion 32 may be molded as a separate member.
FIG. 6 is an enlarged view showing the configuration of the medicine injection device 200 according to the second embodiment. Parts corresponding to those of the first embodiment (see FIG. 5) are denoted by the same reference numerals to avoid duplication. In addition, in this embodiment, since it differs from 1st Embodiment only in the storage part 90 and the needle tube 3 being a separate member, it demonstrates using the enlarged view of the vicinity of this storage part 90 and the needle tube 3 And Other configurations and effects are the same as those of the first embodiment.

In the present embodiment, the needle tube 3 is constituted by the needle body 31 in the first embodiment. A reservoir 90 is connected to the proximal end 3 B of the needle tube 3. The reservoir 90 is a separate member from the needle tube 3, and the needle tube 3 and the reservoir 90 are molded separately.
The reservoir 90 may be made of the same metal as the needle tube 3 such as stainless steel, aluminum, aluminum alloy, titanium, titanium alloy, or the like. Further, since the reservoir 90 is not punctured into the skin, it does not need to be as strong as the needle tube 3 and can be made of, for example, a synthetic resin.
The shape, capacity, and the like of the storage unit 90 are the same as those of the storage unit 32 in the first embodiment.
When the storage part 90 is comprised with a metal, the storage part 90 is connected to the needle tube 3 by welding, for example.

Thus, even if the needle tube 3 and the reservoir 90 are configured as separate members, it is possible to prevent the drug 80 from leaking from the needle tip of the needle tube 3 by storing the drug 80 in the reservoir 90. It is.

The embodiment of the drug injection device has been described above. The present technology is not limited to the above-described embodiments, and includes various conceivable forms without departing from the gist of the present technology described in the claims.

DESCRIPTION OF SYMBOLS 1 ... Injection needle assembly, 2 ... Syringe, 3 ... Needle tube, 3A ... Needle tip, 3a ... Blade surface, 3B ... Base end, 4 ... Needle hub, 5 ... Cap, 6 ... 1st member, 7 ... Elastic member, 8 ... 2nd member, 9 ... Base part, 9a, 9b, 11a, 12a, 15b, 16a, 16b, 42a , 70a, 70b... 10, adjusting portion, 10a... Needle protruding surface, 11... Stabilizing portion, 12... Guide portion, 13. Agent, 15 ... injection hole, 16 ... connection piece, 17, 18 ... vent hole, 19 ... insertion part, 19a, 20a ... cylindrical hole, 20 ... insertion part, 21 ... Fixing piece, 22 ... Groove, 23 ... Stopper, 24 ... Engagement part, 24a, 24b ... Engagement surface, 25 ... Hub side display part, 31 ... Pipe body, 31a ... needle hole, 32, 90 ... storage part, 32a ... storage hole, 41 ... syringe body, 41a ... end face, 42 ... discharge part, 42b ... Discharge port, 43 ... Screw part, 44 ... Syringe side display part, 46 ... Liquid chamber, 70 ... Main body part, 71, 72 ... Flange part, 73 ... Insertion hole, 73a ... Penetration hole, 73b ... embedding hole, 80 ... drug, 81 ... droplet, 82 ... droplet, 100, 110, 200 ... drug injection device

Claims

A needle body having a needle tip to be pierced into the skin and a proximal end opposite to the needle tip; and a storage hole that is continuous with the proximal end of the needle body and communicates with a needle hole of the needle body A storage tube, and a needle tube comprising:
The needle tube that holds the needle tube, the insertion portion into which the discharge portion of the syringe in a state where air is discharged from the inside has a medicine filled inside and a discharge portion that discharges the medicine A holding part for positioning the storage part in the fitting part, and a needle hub,
And the volume of the space in the reservoir is 20 μL or more and 40 μL or less.
The injection needle assembly according to claim 1, wherein an inner diameter of the storage portion of the needle tube is larger than an inner diameter of the needle body.
3. The injection needle assembly according to claim 2, wherein the storage portion has a tapered shape.
4. The injection needle assembly according to claim 3, wherein the storage part is formed integrally with the needle body.
A needle tip punctured into the skin, a needle tube having a proximal end opposite to the needle tip,
A reservoir having a reservoir hole communicating with the needle hole of the needle tube and connected to the proximal end of the needle tube;
The needle tube that holds the needle tube, the insertion portion into which the discharge portion of the syringe in a state where air is discharged from the inside has a medicine filled inside and a discharge portion that discharges the medicine A holding part for positioning the storage part in the fitting part, and a needle hub,
And the volume of the space in the reservoir is 20 μL or more and 40 μL or less.
A needle body having a needle tip to be pierced into the skin and a proximal end opposite to the needle tip; and a storage hole that is continuous with the proximal end of the needle body and communicates with a needle hole of the needle body A storage tube, and a needle tube comprising:
A syringe having a medicine filled therein, a discharge part for discharging the medicine, and air discharged from the inside;
A needle hub having an insertion portion into which the discharge portion of the syringe is inserted, and a holding portion that holds the needle tube and positions the storage portion of the needle tube at the insertion portion;
And the volume of the space in the reservoir is 20 μL or more and 40 μL or less.
An elastic member that has an insertion hole through which the needle tube is inserted and that seals between the needle hub and the needle tube in a liquid-tight manner, and at least a part of the storage portion of the needle tube is embedded in the elastic member; The drug injection device according to claim 6, wherein the drug injection device is inserted.