JP6919798B2 - Indwelling needle assembly - Google Patents

Description

The present invention relates to an indwelling needle assembly that is punctured and indwelled in a blood vessel when performing infusion, blood collection, hemodialysis, etc., and particularly includes a needle tip protector that protects the needle tip of the inner needle after use. It relates to an indwelling needle assembly.

Conventionally, an indwelling needle assembly has been known as a medical tool for performing treatments such as infusion, blood collection, and hemodialysis. The indwelling needle assembly is assembled by inserting an inner needle having an inner needle hub on the proximal end side into an outer needle having an outer needle hub on the proximal end side so as to be retractable. Then, after the inner / outer needle is punctured into the blood vessel of the patient, the inner needle is pulled out from the outer needle, so that the outer needle is placed in the blood vessel of the patient and used for treatment.

Further, as an indwelling needle assembly, a protector that covers the needle tip of the inner needle when the inner needle is pulled out has been proposed in order to prevent erroneous puncture by the inner needle pulled out from the outer needle after puncture. For example, in Japanese Patent Application Laid-Open No. 2001-514943 (Patent Document 1), an elastic arm is extrapolated with respect to the inner needle, and the tip of the elastic arm engages with the inner needle by pulling out the inner needle. A protector has been proposed in which the elastic arm bends inward and can be separated from the outer needle hub when the pressure is released. Further, in Japanese Patent Application Laid-Open No. 2010-0885020 (Patent Document 2), a protector having an arm capable of being displaced inwardly away from the inner needle is integrally provided with the inner needle in the proximal direction. A protector has been proposed in which the arm and the ring member assembled on the inner surface of the outer needle hub come into contact with each other by moving to, and the ring member displaces the arm inward.

However, in the protector described in Patent Document 1, since the total urging force from the elastic arm is always applied to the inner needle, a feeling of pulling resistance always occurs when the inner needle is pulled out. In Patent Document 2, although the urging force from the elastic arm is not applied to the inner needle, a large pull-out resistance force is required when releasing the lock between the ring member and the outer needle hub after the arm is displaced inward. ..

Special Table 2001-514943 Japanese Unexamined Patent Publication No. 2010-08520

The present invention has been made in the background of the above circumstances, and the problem to be solved thereof is to improve the detachment operation from the outer needle hub such as reduction of the resistance force when the inner needle is pulled out. The purpose is to provide an indwelling needle assembly having a new structure.

In the first aspect of the present invention, an inner needle having an inner needle hub on the proximal end side is inserted into an outer needle having an outer needle hub on the proximal end side so as to be pullable, and is pulled out from the outer needle. In an indwelling needle assembly provided with a protector that protects the needle tip of the inner needle, the protector includes an elastic piece that extends toward the needle tip side of the inner needle and is urged laterally. A fixing member having a hinge piece extending toward the needle tip side of the inner needle and having a tip portion locked to the inner surface of the outer needle hub is assembled to the protector so as to be movable in the axial direction. By engaging the restricting portion provided on the elastic piece with the hinge piece, the lateral movement of the elastic piece is restricted, and the elastic piece causes the hinge piece to be the outer needle. It is fixedly held to the inner surface of the hub, and when the inner needle is pulled out from the outer needle, the protector is locked to the inner needle and moves relative to the fixing member in the elastic piece. The restricting portion is disengaged from the hinge piece, the elastic piece of the protector moves laterally to cover the needle tip of the inner needle, and the outer part of the fixing member in the hinge piece. It is characterized in that the needle hub is allowed to move inward in the radial direction, and the fixing member is allowed to be detached from the outer needle hub.

According to the indwelling needle assembly having a structure according to the present invention, the position of the protector with respect to the outer needle hub is realized by the engagement of the hinge piece of the fixing member with the inner peripheral surface of the outer needle hub, and the hinge piece is the protector. Is urged on the inner peripheral surface of the outer needle hub by the elastic piece of. By pulling out the inner needle, the hinge piece can be displaced inward. Therefore, when the inner needle is pulled out, the engagement between the hinge piece and the inner surface of the outer needle hub can be disengaged without causing a large feeling of resistance.

Further , as the protector is moved relative to the fixing member in the axial direction by the pulling operation of the inner needle, the action of the elastic piece of the protector on the fixing member is released, so that the outer needle hub by the fixing member is released. The needle tip protection of the inner needle by the protector at the time of releasing the locked state can be efficiently and surely realized.

Another aspect of the present invention is the indwelling needle assembly according to the first aspect, in which the elastic piece is the inner needle in a state where the hinge piece is fixedly held with respect to the inner surface of the outer needle hub. It is held in a non-contact state with. According to the indwelling needle assembly having a structure according to this embodiment, since the elastic piece of the protector is held in a non-contact state with the inner needle by engaging with the hinge piece of the fixing member, it is held from the outer needle to the inner side. When the needle is pulled out, the elastic piece of the protector is prevented from sliding on the inner needle.

A second aspect of the present invention is the indwelling needle assembly according to the first aspect, in which the hinge piece of the fixing member projects toward the elastic piece side provided with the inner needle sandwiched therein. An engaging protrusion is formed, and by pulling out the inner needle from the outer needle, the restricting portion of the elastic piece moves from the engaging protrusion to the proximal end side, so that the elastic piece is released. It moves sideways to cover the needle tip.

According to the indwelling needle assembly having a structure according to this aspect, it is possible to restrict the inward movement of the protector to the side with a simple configuration. As a result, it is possible to make it difficult for defects to occur.

A third aspect of the present invention is the indwelling needle assembly according to the first or second aspect, wherein the hinge piece of the fixing member has a tip portion in a length direction extending toward the needle tip. A locking portion with respect to the inner surface of the needle hub is provided, and an engaging protrusion is formed in the middle portion in the length direction so as to protrude from the edge portion in the circumferential direction. The restricting portion of the elastic piece is engaged.

In the indwelling needle assembly of the present embodiment, when the restricting portion of the elastic piece is engaged with the engaging protrusion of the hinge piece, for example, the elastic force of the elastic piece is used to lock the locking portion of the hinge piece. It can be maintained in a locked state with respect to the inner surface of the outer needle hub. In addition, by pulling out the inner needle, the regulating part of the elastic piece is separated from the engaging protrusion of the hinge piece, so that the action of the elastic force on the hinge piece is released and the locking of the hinge piece with respect to the outer needle hub is released. It will also be possible to do.

In this embodiment, for example, a pair of elastic pieces urged in an approaching direction so as to face each other in a direction orthogonal to the needle axis, and the outside of the pair of elastic pieces are directed toward the needle tip side of the inner needle, respectively. It is possible to adopt a mode in which a pair of hinge pieces extending in the direction is provided, and a mode in which the urging force in each regulating portion provided on the pair of elastic pieces is exerted on the pair of hinge pieces, respectively. In such an embodiment, the pair of hinge pieces are separated from each other in the opposite direction by the urging force exerted by the pair of elastic pieces to be engaged with the inner peripheral surface of the outer needle hub, and the restricting portion of the pair of elastic pieces. Is disengaged from the engaging protrusions of the pair of hinge pieces and the pair of hinge pieces approach each other in the opposite direction so that the engagement of the outer needle hub with the inner peripheral surface is released. Then, by engaging the restricting portion of the elastic piece with the engaging protrusion provided in the intermediate portion in the length direction of each hinge piece, the amount of movement in the opposite direction at the tip portions of the pair of hinge pieces is secured. However, the elasticity of the elastic piece can be exerted. In addition, when the inner needle is pulled out, the protector moves relative to the fixing member, and the regulating part of the elastic piece is disengaged from the engaging protrusion, so that the elastic action of the elastic piece on the hinge piece is released and the protector. The protection of the needle tip and the release of the locked state of the fixing member from the outer needle hub can be efficiently realized.

A fourth aspect of the present invention is the indwelling needle assembly according to any one of the first to third aspects, wherein the elastic piece of the protector is provided with an engaging piece that projects laterally. The regulating portion is configured, and the engaging piece is engaged with the hinge piece of the fixing member.

In the indwelling needle assembly of this embodiment, the elastic piece is projected outward from the side surface of the elastic piece, for example, in the lateral direction intersecting the direction in which the elastic piece is displaced by elasticity in order to protect the needle tip of the inner needle. By engaging at least one engaging piece with the hinge piece, a force transmission structure that exerts the elasticity of the elastic piece on the engaging piece while sufficiently avoiding the influence of the elastic piece on the needle tip protection structure of the inner needle. Can be easily realized.

A fifth aspect of the present invention is the indwelling needle assembly according to any one of the first to fourth aspects, wherein the valve body and the valve body are pushed open from the proximal end side to the outer needle hub. The pusher is incorporated in a housed state, and the tip end portion of the hinge piece in the fixing member is arranged so as to extend from the base end side of the outer needle hub to the outer periphery of the pusher. be.

In the indwelling needle assembly of this embodiment, in a structure in which the indwelling needle is blocked to stop bleeding, and the valve body and pusher to be communicated with each other when inserting a male lure or the like into the outer needle hub are housed and arranged in the outer needle hub. It is possible to arrange the fixing members in a space-saving manner while suppressing the increase in size of the outer needle hub and the indwelling needle assembly in the length direction.

A sixth aspect of the present invention is the indwelling needle assembly according to any one of the first to fifth aspects, wherein the base end portion of the protector is provided with an insertion hole through which the inner needle is inserted. While both are provided with a guide surface extending in the length direction of the inner needle, the base end portion of the fixing member is provided with a mounting hole to be externally inserted into the base end portion of the protector. The base end portion of the fixing member is assembled so as to be relatively movable in the axial direction along the guide surface of the protector.

In the indwelling needle assembly of this embodiment, when the inner needle is pulled out, the protector can be moved more stably and relative to the fixing member together with the inner needle. As a result, the disengagement of the regulating portion in the elastic piece of the protector with respect to the hinge piece of the fixing member can be more smoothly realized, and the pull-out resistance of the inner needle can be further reduced.

In addition, according to the indwelling needle assembly having a structure according to this embodiment, for example, the hinge piece of the fixing member is urged toward the inner peripheral surface of the outer needle hub and locked by the elastic force in the elastic piece of the protector. In addition to being held in a state, the action of the guide surface at the base end of the protector works, so that in the state before the inner needle pulling operation such as before using the indwelling needle assembly, the elastic piece of the protector and the hinge of the fixing member Excessive rattling between the piece and each member such as the outer needle hub can be suppressed, and a stable assembled state can be maintained.

A seventh aspect of the present invention is the indwelling needle assembly according to any one of the first to sixth aspects, wherein the fixing member is attached to the fixing member from both side edges of a base end portion attached to the protector. The hinge piece extending toward the needle tip side of the needle is formed, and a folding portion that allows bending in the opposite direction is provided on the base end side of the hinge piece.

In the indwelling needle assembly of this embodiment, by adopting a hinge piece elongated in the axial direction and providing a foldable portion on the proximal end side, it is possible to easily bend in the direction without the hinge piece. Further, the degree of freedom in designing the member is improved, and for example, in the intermediate portion in the length direction of the hinge piece, it becomes possible to easily set the elastic acting portion by the regulating portion of the elastic piece of the protector.

An eighth aspect of the present invention is the indwelling needle assembly according to any one of the first to seventh aspects, wherein the elastic piece of the protector is engaged with the hinge piece of the fixing member. In a state where the tip end portion of the hinge piece is locked to the inner surface of the outer needle hub, each base end portion of the protector and the fixing member projects outward from the base end side opening of the outer needle hub. At the same time, each tip portion of the elastic piece of the protector and the hinge piece of the fixing member is inserted inward from the base end side opening of the outer needle hub.

In the indwelling needle assembly of this embodiment, the indwelling needle is accommodated in the inner needle hub by accommodating the protector and each base end side portion of the fixing member assembled in a state of protruding from the base end side opening of the outer needle hub. It is possible to suppress the increase in size of the assembly in the length direction.

A ninth aspect of the present invention is the indwelling needle assembly according to any one of the first to eighth aspects, wherein a locking convex portion is provided on the outer peripheral surface of the tip end portion of the hinge piece of the fixing member. On the other hand, the inner peripheral surface of the outer needle hub is provided with a locking recess for locking the locking protrusion, and at least one of the locking protrusion and the locking recess. The base end side edge portion is provided with an inclined surface that guides the locking convex portion in the direction of disengagement from the locking recess when the fixing member moves in the pulling direction from the outer needle hub. Is.

In the indwelling needle assembly of this embodiment, the hinge piece of the fixing member and the inner peripheral surface of the outer needle hub are realized by a concave-convex locking structure, and the elasticity applied from the elastic piece of the protector to the hinge piece of the fixing member is released. When the fixing member is pulled out, the pulling resistance due to the uneven locking structure can be further reduced by the guiding action of the inclined surface.

A tenth aspect of the present invention relates to the regulation unit in the indwelling needle assembly according to any one of the first to ninth aspects, with the hinge piece urged sideways. The hinge pieces are fitted, and when the engagement between the hinge piece and the regulating portion is released, the hinge piece automatically moves in the inner diameter direction of the outer needle hub.

According to the indwelling needle assembly having a structure according to this aspect, since the hinge piece automatically moves inward, it is possible to make it difficult for a defect to occur.

In the eleventh aspect of the present invention, the inner needle having the inner needle hub on the proximal end side is inserted into the outer needle having the outer needle hub on the proximal end side so as to be pullable, and is pulled out from the outer needle. In an indwelling needle assembly provided with a protector that moves on the needle axis of the inner needle, a fixing member is provided in the outer needle hub at a position facing the protector, and the protector is provided with respect to the fixing member. By being provided in the urged state, the lateral movement of the protector is restricted, the protector is held in a non-contact state with the inner needle, and the fixing member is held by the protector. It is fixedly held to the outer needle hub, and by pulling out the inner needle from the outer needle, the protector is locked to the inner needle, and the inner needle and the protector move relative to the fixing member. By doing so, the protector moves laterally and moves on the needle axis of the inner needle, and at the same time, the fixing member is allowed to move inward in the radial direction of the outer needle hub, and the outer part of the fixing member is allowed to move. It is characterized in that it is allowed to be detached from the needle hub.

According to the indwelling needle assembly having a structure according to this aspect, the resistance between the protector and the inner needle can be set to zero. As a result, the length at which resistance is generated can be shortened.

In the twelfth aspect of the present invention, the inner needle having the inner needle hub on the proximal end side is inserted into the outer needle having the outer needle hub on the proximal end side so as to be pullable, and is pulled out from the outer needle. In an indwelling needle assembly provided with a protector that moves on the needle axis of the inner needle, a fixing member having a fixing portion on the outer surface is provided in the outer needle hub at a position facing the protector, and the protector is provided. By being provided in contact with the fixing member, the protector is prevented from moving laterally, the protector is held in a non-contact state with the inner needle, and the protector is fixed. The member is prevented from moving inward in the radial direction of the outer needle hub, the fixing member is positioned in the outer needle hub, and by pulling out the inner needle from the outer needle, the protector is moved to the inner needle. When the inner needle and the protector move relative to the fixing member, the protector moves laterally and moves on the needle axis of the inner needle, and the fixing member has the same shape. The outer needle hub is allowed to move inward in the radial direction, and the fixing member is allowed to be detached from the outer needle hub.

According to the indwelling needle assembly having a structure according to this aspect, the resistance between the protector and the inner needle can be set to zero. As a result, the length at which resistance is generated can be shortened.

In the thirteenth aspect of the present invention, the inner needle having the inner needle hub on the proximal end side is inserted into the outer needle having the outer needle hub on the proximal end side so as to be pullable, and is pulled out from the outer needle. In an indwelling needle assembly provided with a protector that moves on the needle axis of the inner needle, a fixing member is provided in the outer needle hub at a position facing the protector, and the protector is provided with respect to the fixing member. By being provided in the urged state, the lateral movement of the protector is restricted, the protector is held in contact with the inner needle and the fixing member, and the fixing member is held by the protector. Is fixedly held to the outer needle hub, and by pulling out the inner needle from the outer needle, the protector is locked to the inner needle, and the inner needle and the protector are attached to the fixing member. By relative movement, the protector moves laterally and moves on the needle axis of the inner needle, and the fixing member is allowed to move inward in the radial direction of the outer needle hub of the fixing member. It is characterized in that the detachment from the outer needle hub is allowed.

According to the indwelling needle assembly having a structure according to this embodiment, since a part of the urging force from the protector is applied to the fixing member, the sliding between the inner needle and the protector that occurs when the inner needle is pulled out from the outer needle. Resistance is reduced.

In the indwelling needle assembly having a structure according to the present invention, it is possible to improve the detachment operation from the outer needle hub, such as reducing the resistance force when the inner needle is pulled out.

The perspective view which shows the main part in the initial state of the indwelling needle assembly as the 1st Embodiment of this invention. A perspective view of the indwelling needle assembly shown in FIG. 1 from another direction. A side view of the indwelling needle assembly shown in FIG. FIG. 3 is a vertical cross-sectional view of the indwelling needle assembly shown in FIG. FIG. 4 is a perspective view of a vertical cross section shown in FIG. FIG. 3 is a perspective view of a protector constituting the indwelling needle assembly shown in FIG. FIG. 6 is a side view of the protector shown in FIG. The plan view of the protector shown in FIG. FIG. 3 is an enlarged perspective view showing one engaging portion of the elastic piece and the hinge piece in the indwelling needle assembly shown in FIG. 1. FIG. 3 is an enlarged perspective view showing an enlarged portion of the other engaging portion between the elastic piece and the hinge piece in the indwelling needle assembly shown in FIG. FIG. 1 is a perspective view corresponding to FIG. 1, showing a state in which the elastic piece is disengaged from the hinge piece by pulling out the inner needle in the indwelling needle assembly shown in FIG. FIG. 11 is a vertical cross-sectional view of the indwelling needle assembly shown in FIG. FIG. 1 is a perspective view corresponding to FIG. 1, showing a state in which the protector and the fixing member are separated from the outer needle hub by pulling out the inner needle in the indwelling needle assembly shown in FIG. FIG. 13 is a vertical cross-sectional view of the indwelling needle assembly shown in FIG. The vertical sectional view which shows the main part in the initial state of the indwelling needle assembly as the 2nd Embodiment of this invention. FIG. 15 is a view showing a needle tip protector mechanism constituting the indwelling needle assembly shown in FIG. 15, in which (a) is a perspective view, (b) is a front view, and (c) is a perspective view from another direction. (D) is the rear view. 16A and 16B are perspective views showing a state in which the protector is displaced toward the base end side with respect to the fixing member as the inner needle is pulled out in the needle tip protector mechanism shown in FIG. The front view, (c) is a perspective view from another direction, and (d) is a rear view.

Hereinafter, in order to clarify the present invention in more detail, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 to 5 show an indwelling needle assembly 10 as a first embodiment of the present invention. The indwelling needle assembly 10 includes an inner needle unit 12 and an outer needle unit 14 that are detachably assembled from each other. In this specification, when performing a needle puncture procedure on a patient using the indwelling needle assembly 10, the left side in FIGS. 3 and 4, which is the side distal to the practitioner, is the tip side, and The end of the indwelling needle assembly located on such a distal side, or the end of each member constituting them, is referred to as a tip, and is in FIGS. 3 and 4 on the proximal side of the practitioner. The right side is referred to as the proximal end side, and such a proximal end side end is referred to as a proximal end portion. Further, the axial direction and the length direction refer to the left-right direction in FIGS. 3 and 4 which is the needle axis direction of the indwelling needle, and the up-down direction means the up-down direction in FIGS. 3 and 4.

More specifically, the inner needle unit 12 includes an inner needle 18 having a needle tip 16 at the tip thereof and an inner needle hub 20 provided on the base end side of the inner needle 18. The inner needle 18 is made of a known material such as stainless steel, aluminum, titanium or an alloy thereof, and the inner needle hub 20 is made of, for example, a hard synthetic resin. A large diameter portion 22 having a slightly larger outer diameter than the other portions is provided at the tip of the inner needle 18, and in the present embodiment, the large diameter portion 22 is the inner needle 18. It is provided over the entire circumference in the circumferential direction of.

The inner needle 18 may be a solid needle, but in the present embodiment, a hollow needle is adopted. Then, for example, as described in Japanese Patent Application Laid-Open No. 2012-1330523, the hollow needle (inner needle 18) is placed in a known internal space for checking back blood provided on the base end side of the inner needle hub 20. The base end side is communicated. Note that FIGS. 1 and 2 omit the illustration of the inner needle hub 20, and FIG. 5 shows a state in which the inner needle unit 12 is moved to the proximal end side to some extent from the state shown in FIGS. 1 to 4. In addition, other known means for confirming back blood may be used.

Further, the tip portion of the inner needle hub 20 is a tubular accommodating cylinder portion 24 that opens to the tip side, and a part of the circumference of the accommodating cylinder portion 24 (lower part in FIGS. 3 and 4) A positioning protrusion 26 projecting to the tip side is provided. The inner needle hub 20 and the outer needle hub 30, which will be described later, are positioned by the positioning protrusion 26, and a pair of user gripping portions (thumb and index finger mounting portions) and an outer needle formed on the inner needle hub 20. The wing-shaped portion 46, which will be described later, formed on the hub 30 can be positioned in a suitable state. The positioning protrusion 26 may not be provided.

On the other hand, the outer needle unit 14 includes an outer needle 28 and an outer needle hub 30 provided on the proximal end side of the outer needle 28. The outer needle 28 has a tube shape having a length shorter than that of the inner needle 18, and the tip portion thereof is, for example, a tapered portion whose diameter gradually decreases toward the tip side. Thereby, the puncture resistance to the living body can be reduced. Further, the inner diameter dimension of the outer needle 28 is substantially equal to or slightly larger than the outer diameter dimension of the inner needle 18, so that the inner needle 18 can be inserted into the outer needle 28. The peripheral wall at the tip of the outer needle 28 may be provided with one or more through holes, which can improve the flow efficiency of the fluid with respect to the outer needle 28. The outer needle 28 can be preferably formed by, for example, a soft synthetic resin.

Further, the outer needle hub 30 has a substantially tubular shape extending in the axial direction as a whole, and is preferably formed of, for example, a hard synthetic resin similar to the inner needle hub 20. The inner surface 31a and the outer surface 31b of the outer needle hub 30 have a larger diameter at the base end side than the tip end side, and the inner diameter dimension at the tip end portion is substantially equal to the outer diameter dimension of the outer needle 28. A substantially tubular caulking pin 32 is fixed to the inner surface 31a of the tip portion of the outer needle hub 30, and the base end portion of the outer needle 28 is inserted between the caulking pin 32 and the outer needle hub 30 in the radial direction. The outer needle 28 extends from the tip of the outer needle hub 30 by performing a treatment such as adhesion as necessary. The caulking pin 32 can be suitably formed of, for example, metal or the like, and the strength of the connecting portion between the outer needle hub 30 and the outer needle 28 can be improved.

Further, in the base end side opening 34 of the outer needle hub 30, a flange portion 36 projecting to the outer peripheral side is provided on the outer surface 31b of the outer needle hub 30. The inner diameter dimension of the base end side opening 34 of the outer needle hub 30 is substantially equal to the inner diameter dimension of the accommodating cylinder portion 24, and the outer needle is in the assembled state of the inner needle unit 12 and the outer needle unit 14 described later. The inside of the hub 30 and the inside of the accommodating cylinder 24 are vertically communicated with each other.

Further, on the outer peripheral surface of the flange portion 36, a positioning groove 38 extending in the axial direction is provided at a position (lower side in FIGS. 3 and 4) corresponding to the positioning protrusion 26 on the inner needle hub 20 on the circumference. .. A screw thread is provided on the outer peripheral surface of the flange portion 36 in a portion that is deviated from the positioning groove 38 in the circumferential direction. A connector etc. can be connected.

Furthermore, the inner surface 31a at the tip of the outer needle hub 30 is provided with a locking recess 40 that extends over the entire circumference in the circumferential direction and opens to the inner circumference side. In the present embodiment, of the inner surfaces constituting the locking recess 40, the axial intermediate portion is an annular flat surface extending in the axial direction, while both end portions in the axial direction are inclined surfaces inclined with respect to the axial direction. It is said to be 42a and 42b. That is, the inclined surface 42a provided on the distal end edge portion has an inner diameter gradually increased toward the proximal end side, while the inclined surface 42b provided on the proximal end side edge portion is on the proximal end side. The inner diameter is gradually reduced toward. It should be noted that the configuration may be such that the inclined surfaces 42a and 42b are not provided.

Further, on the inner surface 31a of the outer needle hub 30, a positioning protrusion 44 for a hemostatic valve mechanism protruding toward the inner peripheral side is formed on the tip end side of the locking recess 40. In the present embodiment, the positioning protrusions 44 for the hemostatic valve mechanism are formed at four locations on the periphery at substantially equal intervals.

On the other hand, the outer surface 31b of the outer needle hub 30 is provided with a pair of wing-shaped portions 46, 46 projecting on both sides in the radial direction (in the front-back direction of the paper surface in FIG. 3).

A hemostatic valve mechanism 48 is incorporated in the outer needle hub 30 as described above in a housed state. The structure of the hemostatic valve mechanism 48 is not limited in any way, but in the present embodiment, it is composed of a disc valve 50 as a valve body, a pusher 52, and a pusher guide 54.

The disc valve 50 has a slit 56 (see FIG. 12) formed in the center thereof, and is made of a rubber elastic body or an elastomer. Further, the pusher 52 has a substantially tubular shape as a whole, and the inner diameter dimension is larger than the outer diameter dimension of the inner needle 18. Further, the pusher guide 54 has a substantially tubular shape as a whole, and the pusher guide 54 is arranged between the pusher 52 and the outer needle hub 30 in the radial direction on the inner surface 31a of the outer needle hub 30. It is positioned and fixed in the axial direction by the positioning protrusion 44 provided. The disc valve 50 is mounted inside the outer needle hub 30, and the pusher 52 and the pusher guide 54 are located on the base end side of the disc valve 50, and the pusher 52 is the pusher guide 54. It slides against the object and can move in the axial direction.

Then, after the outer needle 28 is placed on the skin of the patient, a syringe or the like is inserted from the proximal end side opening 34 of the outer needle hub 30, so that a male luer such as the tip of the syringe pushes the pusher 52 toward the tip. The slit 56 of the disc valve 50 is pushed open from the base end side to open the disc valve 50. As a result, the inside of the syringe or the like and the outer needle 28 are communicated with each other. By removing the syringe or the like from the outer needle hub 30, the slit 56 is quickly closed by the elastic restoring action of the disc valve 50.

The indwelling needle assembly 10 is configured by assembling the inner needle unit 12 to the outer needle unit 14 having the above-mentioned structure. That is, the inner needle 18 is inserted into the outer needle unit 14 from the base end side, penetrates the disc valve 50, and the needle tip 16 of the inner needle 18 projects from the tip of the outer needle 28. .. In such an assembled state, the positioning protrusion 26 provided on the inner needle hub 20 is inserted into the positioning groove 38 provided at the base end of the outer needle hub 30, and the outer needle unit 14 and the inner needle unit 12 are combined. Relative rotation is prevented.

Then, the indwelling needle assembly 10 composed of the assemblies of the inner and outer needle units 12 and 14 is punctured from the needle tip of the patient, and then the inner needle 18 is pulled out from the outer needle unit 14 to allow the outer needle unit 14 to move. It is designed to be placed on the patient's skin.

Here, the indwelling needle assembly 10 is provided with a needle tip protector mechanism 58 that protects the needle tip 16 of the inner needle 18 pulled out from the outer needle 28 after puncturing. The needle tip protector mechanism 58 includes a protector 60 that is extrapolated to the inner needle 18 and a fixing member 62 that is assembled to the outer periphery of the protector 60 and extends toward the tip end side in the axial direction. It is composed of.

The protector 60 is a metal member made of NiTi alloy, stainless steel, or the like, and as shown in FIGS. 6 to 8, it has a substantially square cylinder shape with a bottom as a whole. The protector 60 can be formed, for example, by cutting a metal base plate into a predetermined shape and pressing it a plurality of times. The protector may be a resin member, or a member that generates an elastic force for moving the protector on the needle shaft may be separately provided. Further, the shape of the protector is not limited to the elastic piece, and may be, for example, a ball member. Further, in FIGS. 6 to 8, the protector 60 is shown in a state of being assembled in the indwelling needle assembly 10 in the initial state shown in FIGS. 1 to 5.

That is, the protector 60 is provided with a rectangular bottom wall portion 64 at the base end, and a first elastic piece 66 and a second elastic piece 66 extending toward the tip end side from the upper and lower side edge portions of the bottom wall portion 64. The pieces 68 are formed so as to face each other. Further, side plate portions 70 and 72 extend from the first and second elastic pieces 66 and 68, and the side plate portions 70 and 72 are located on the sides of the first and second elastic pieces 68. And extends to the tip side. The side plate portions 70 and 72 face each other in a direction orthogonal to the facing direction of the first and second elastic pieces 66 and 68. The protector 60 is configured as a bottomed substantially square tube shape by the bottom wall portion 64, the first and second elastic pieces 66, 68, and the side plate portions 70, 72.

In the axially intermediate portion of the protector 60, the tip of one side plate portion 72 is bent and spreads in the direction perpendicular to the axis, forming the intermediate plate portion 74. Insertion holes 76 and 78 are formed in the centers of the bottom wall portion 64 and the intermediate plate portion 74, respectively. The inner diameter of the insertion hole 76 provided in the bottom wall portion 64 is larger than the outer diameter of the portion of the inner needle 18 where the large diameter portion 22 is not provided, and smaller than the outer diameter of the large diameter portion 22. There is. On the other hand, the inner diameter dimension of the insertion hole 78 provided in the intermediate plate portion 74 is larger than the outer diameter dimension of the large diameter portion 22 of the inner needle 18.

The first elastic piece 66 extends from the upper edge of the bottom wall portion 64 toward the tip end side, while the second elastic piece 68 extends from the lower edge portion of the bottom wall portion 64 toward the tip end side. Both elastic pieces 66 and 68 have a substantially rectangular plate shape having predetermined axial dimensions. Further, the base end portions of both elastic pieces 66 and 68 extend in the substantially axial direction, and the outer surfaces 80 and 81 of the base end portions are flat surfaces. Further, the tip side from the axial intermediate portion of both elastic pieces 66 and 68 can be elastically deformed in the opposite direction of both elastic pieces 66 and 68, and the tip portion thereof is within the opposite direction as compared with the intermediate portion. It bends slightly in a dogleg shape. At the tips of both elastic pieces 66 and 68, folded portions 82 and 84 that fold back toward the elastic pieces on the opposite sides are provided.

In the initial state shown in FIGS. 1 to 5 (states shown in FIGS. 6 to 8), the first and second elastic pieces 66 and 68 are shown in a state of being elastically deformed outward in the opposite direction. In the single item state before being assembled to the inner needle 18, the first and second elastic pieces 66 and 68 extend in the substantially axial direction, and the vicinity of the vertices of both folded portions 82 and 84 overlap each other in the axial direction. It has become like. That is, in the protectors 60 shown in FIGS. 6 to 8, the first and second elastic pieces 66 and 68 are elastically deformed outward in the opposite direction from the single item state, and the first and second elastic pieces 66, In 68, the urging force associated with the elastic restoring force is exerted inward in the opposite direction, which is the direction in which they approach each other. In the present embodiment, the sides of the first and second elastic pieces 66 and 68, which are the directions of action of the urging forces, are set to be inward facing each other.

Here, from the folded portions 82 and 84 provided at the tips of both elastic pieces 66 and 68, engaging pieces 86 and 88 projecting laterally from the edge portion in the width direction are provided, respectively. The engaging pieces 86 and 88 extend in a direction orthogonal to the opposite direction of the elastic pieces 66 and 68, respectively, and extend in opposite directions to each other. That is, the engaging piece 86 extends from the first elastic piece 66 toward the right in FIG. 8, while the engaging piece 86 engages from the second elastic piece 68 toward the left in FIG. The plaque 88 extends out. In the present embodiment, these engaging pieces 86, 88 are formed in the shape of a plate piece that continuously extends from the folded-back portions 82, 84. Further, in the present embodiment, side wall plates 89 and 89 extending toward the second elastic piece 68 are provided on both sides of the first elastic piece 66 in the width direction, and the side wall plates 89 are engaged with the side wall plates 89. Appropriate notches are provided to avoid interference of piece 88.

Further, in the present embodiment, in the axially intermediate portion of the first elastic piece 66 and the second elastic piece 68, the through window 90, which penetrates in the thickness direction with a predetermined axial dimension in the central portion in the width direction, 92 is formed. Then, elastic projectiles 94, 96 extending toward the tip side are formed from the inner peripheral surface of the through windows 90, 92 on the base end side. The three sides around the elastic projectiles 94 and 96 are not connected to the first and second elastic pieces 66 and 68, and the elastic projectiles 94 and 96 are elastically deformable in the plate thickness direction. As shown in FIG. 5 and the like, the elastic projectiles 94 and 96 are provided so as to project outward from the first and second elastic pieces 66 and 68 in the opposite direction. The elastic projectiles 94 and 96 are configured to restrict the movement of the protector 60 with respect to the fixing member 62 in the tip direction after use, but the first and second elastic pieces 66 and 68 and the fixing member 62 are used. The relative movement of the protector 60 with respect to the fixing member 62 after use may be restricted, in which case the elastic projectiles 94 and 96 are unnecessary.

On the other hand, the fixing member 62 has a substantially bottomed tubular shape as a whole, and is integrally formed of, for example, a hard synthetic resin. That is, the base end wall portion 100 is provided at the base end, and a pair of hinge pieces 102, 104 extend from the base end wall portion 100 toward the tip end side. The base end wall portion 100 has a substantially rectangular shape, and a substantially rectangular mounting hole 105 is formed in the center. In the base end wall portion 100, recesses 106 and 106 that open to the base end side are formed on the upper and lower side base end surfaces that sandwich the mounting hole 105. The fixing member 62 may be made of metal, and the hinge pieces 102 and 104 and the base end wall portion 100 are separately formed and then fixed to form a single member. You may.

A pair of hinge pieces 102 and 104 are hinged to the upper and lower side edges of the base end wall portion 100. That is, these hinge pieces 102 and 104 are connected to the base end wall portion 100 via thin-walled foldable portions 107 and 107. By providing the foldable portions 107 and 107 on the base end side of the hinge pieces 102 and 104, the tip ends of the hinge pieces 102 and 104 can be bent inward in the opposite direction. There is. Each of the hinge pieces 102 and 104 has an axial dimension larger than that of the protector 60, and each has a substantially rectangular plate shape on the base end side, while the tip end side has a substantially curved plate shape having a circumferential dimension less than half a circumference. It is said that they face each other in the vertical direction. As a result, between the circumferential directions of the pair of hinge pieces 102 and 104, the gaps 108 and 108 between the facing sides extending over substantially the entire axial direction of the fixing member 62 are orthogonal to the facing directions of the hinge pieces 102 and 104. It is formed so as to face each other and is open to the tip side.

Here, engaging protrusions 110 and 112 extending toward the hinge pieces on opposite sides are formed from the axially intermediate portions of the hinge pieces 102 and 104, respectively. These engaging protrusions 110 and 112 project from the opposite circumferential end portions of the hinge pieces 102 and 104 into the opposing gaps 108 and 108 toward the inward facing direction, and face each other in the direction perpendicular to the axis. doing. That is, the upper hinge piece 102 is provided with an engaging protrusion 110 that projects toward the lower hinge piece 104 at the circumferential end on the front side in FIG. 1, while the lower hinge piece 104 is shown in FIG. An engaging protrusion 112 that protrudes toward the upper hinge piece 102 is provided at the circumferential end of 1 on the inner back side (front side in FIG. 2). In the present embodiment, these engaging protrusions 110 and 112 are provided at the tip portions of both hinge pieces 102 and 104 having a substantially rectangular plate shape on the proximal end side. By providing the engaging protrusions 110 and 112, the facing distance between the hinge pieces 102 and 104 is reduced at the forming position of the engaging protrusions 110 and 112.

Further, the tip portions of the hinge pieces 102 and 104 are formed with locking convex portions 114 and 114 as locking portions protruding toward the outer peripheral side. In the present embodiment, these locking protrusions 114, 114 are provided at the tips of the portions of both hinge pieces 102, 104 having a substantially curved plate shape on the tip side, over substantially the entire circumference in the circumferential direction. ..

The protector 60 and the fixing member 62 having the above structure are assembled to each other. That is, the protector 60 is inserted into the mounting hole 105 provided in the base end wall portion 100 of the fixing member 62, in other words, the base end wall portion 100 having the mounting hole 105 is extrapolated to the protector 60. The fixing member 62 is located on the outer peripheral side of the base end portion of the protector 60. That is, the hinge pieces 102 and 104 of the fixing member 62 are located outside the first and second elastic pieces 66 and 68 of the protector 60. As a result, the protector 60 is supported so as to be movable in the axial direction with respect to the fixing member 62. In particular, the outer surface 80, 81 of the base end portion of the first and second elastic pieces 66, 68 of the protector 60 and the outer surface of the side plate portions 70, 72 come into contact with the inner surface of the mounting hole 105, whereby the base of the fixing member 62 is formed. The end wall portion 100 is movable in the axial direction along the outer surfaces of the outer surfaces 80 and 81 and the side plate portions 70 and 72 of the protector 60. As a result, the protector 60 and the fixing member 62 can move relative to each other in the axial direction without being displaced in the direction perpendicular to the axis. Therefore, the outer surfaces 80, 81 of the base end portions of the first and second elastic pieces 66, 68 and the outer surfaces of the side plate portions 70, 72 form a guide surface at the base end portion of the protector 60, and the guide surface is formed. The surface extends axially.

A needle tip protector mechanism 58 including the protector 60 and the fixing member 62 is inserted through the inner needle 18. That is, the protector 60 is inserted from the tip end side opening of the fixing member 62 and is projected toward the proximal end side through the proximal end wall portion 100, and the inner needle 18 is inserted from the distal end side of the needle tip protector mechanism 58. The base end portion is fixed to the inner needle hub 20. Therefore, the inner needle 18 is inserted into the insertion holes 76 and 78 of the protector 60 so that the needle tip protector mechanism 58 can move in the axial direction with respect to the inner needle 18.

When the inner needle unit 12 and the outer needle unit 14 shown in FIGS. 1 to 5 are assembled, the tip end side of the needle tip protector mechanism 58 (protector 60 and fixing member 62) is the base end of the outer needle hub 30. While being inserted inward from the side opening 34, the proximal end side of the needle tip protector mechanism 58 (protector 60 and fixing member 62) protrudes outward from the proximal end side opening 34 of the outer needle hub 30, and the inner needle hub. It is inserted into the accommodating cylinder portion 24 of 20. Further, the hinge pieces 102 and 104 of the fixing member 62 are inserted from the base end side opening 34 of the outer needle hub 30 and extend the outer peripheral side of the pusher 52 toward the tip end side, and the locking convex provided at the tip end thereof. The portions 114 and 114 enter into the locking recess 40 provided on the inner surface 31a of the outer needle hub 30 and are locked.

Here, in such an assembled state, the engaging pieces 86, 88 provided on the first and second elastic pieces 66, 68 of the protector 60 are the tips of the opposing gaps 108, 108 provided on the fixing member 62. Inserted from the side opening, as shown in FIGS. 9 and 10, the engaging protrusion 112 and the hinge piece 102 provided on the hinge piece 104, and the engaging protrusion 110 provided on the hinge piece 102, respectively. It is sandwiched between and held by the hinge piece 104. That is, the engaging pieces 86, 88 are engaged with the engaging protrusions 112, 110, and the first and second elastic pieces 66, 68 are prevented from being deformed inward in the opposite direction, so that the first elastic piece 86, 88 is prevented from being deformed inward. And the second elastic pieces 66, 68 are maintained in a state of being deformed outward in the opposite direction as shown in FIGS. 6 to 8. Therefore, in the present embodiment, the restricting portion provided on the first and second elastic pieces 66 and 68 and engaged with the hinge pieces 104 and 102 is composed of the engaging pieces 86 and 88.

Then, the engaging pieces 86, 88 provided on the first and second elastic pieces 66, 68 abut on the hinge pieces 102, 104 from the inside, so that the hinge pieces 102, 104 are displaced inward in the opposite direction. Is blocked. In addition, the first and second elastic pieces 66 and 68 are urged inward in the opposite direction, so that the hinge pieces 104 and 102 are opposed to each other via the engaging protrusions 112 and 110. It is urged outward, that is, toward the inner surface 31a of the outer needle hub 30. As a result, the engagement between the locking protrusions 114 and 114 and the locking recess 40, that is, the connection between the needle tip protector mechanism 58 and the outer needle hub 30 is stably maintained.

Further, at the time of such assembly, since the first and second elastic pieces 66 and 68 are maintained in a deformed state outward in the opposite direction, the folded portions 82 of the first and second elastic pieces 66 and 68, The 84 does not come into contact with the inner needle 18, and both elastic pieces 66 and 68 are held in a non-contact state with the inner needle 18.

In order to protect the needle tip 16 of the inner needle 18 by the needle tip protector mechanism 58 having the above structure, the inner needle 18 is pulled out from the outer needle unit 14 after the indwelling needle assembly 10 is punctured. Here, since the outer diameter dimension of the large diameter portion 22 provided on the inner needle 18 is larger than the inner diameter dimension of the insertion hole 76 provided on the bottom wall portion 64 of the protector 60, the inner needle 18 can be pulled out. As a result, the large diameter portion 22 of the inner needle 18 is locked to the bottom wall portion 64 of the protector 60. By further pulling out the inner needle 18 from such a locked state, as shown in FIGS. 11 and 12, the protector 60 is moved to the proximal end side with respect to the fixing member 62 together with the inner needle 18.

In the present embodiment, elastic projecting pieces 94 and 96 projecting outward in the opposite direction are provided at the axially intermediate portions of the first and second elastic pieces 66 and 68, and these are the protectors 60. When moving to the base end side with respect to the fixing member 62, it is brought into contact with the inner surface of the mounting hole 105. As a result, the elastic projectiles 94 and 96 are pushed inward in the opposite direction, but are elastically restored and deformed as the mounting hole 105 passes, and after passing through the mounting hole 105, the first and second elastic pieces are again formed. It is projected outward in the opposite direction of 66 and 68, and is fitted into recesses 106 and 106 provided on both the upper and lower sides of the mounting hole 105. As a result, the elastic projecting pieces 94, 96 come into contact with the base end wall portion 100 of the fixing member 62, so that the protector 60 moves to the tip side with respect to the fixing member 62 after passing through the mounting hole 105 by the elastic projecting pieces 94, 96. Movement can be blocked.

Then, the protector 60 is further moved to the base end side with respect to the fixing member 62, so that the engaging piece 86 located between the hinge piece 102 and the engaging protrusion 112 facing each other is moved to the engaging protrusion. It moves to the base end side from 112, and the engagement between the engaging piece 86 and the engaging protrusion 112 is released. Similarly, the engaging piece 88 located between the hinge piece 104 and the engaging protrusion 110 is moved from the engaging protrusion 110 to the proximal end side, and the engaging piece 88 and the engaging protrusion 110 are moved. The engagement with is released. As a result, the first and second elastic pieces 66,68 move inward in the opposite direction to the side of the protector 60 according to the urging force, and are provided at the tips of the first and second elastic pieces 66,68. The needle tip 16 of the inner needle 18 is covered by the folded-back portions 82 and 84, and the needle tip 16 of the inner needle 18 is protected by the protector 60.

Then, the hinge pieces are prevented from being displaced inward in the opposite direction by the inward movement of the engaging pieces 86, 88 provided on the first and second elastic pieces 66, 68 in the opposite direction. Displacement of 102, 104 inward in the opposite direction can be tolerated. That is, the hinge pieces 104 and 102 were urged outward in the opposite direction by the first and second elastic pieces 66 and 68, but when the urging was released, the hinge pieces 102 and 104 faced each other. Inward displacement can be tolerated.

Then, while the hinge pieces 102 and 104 are allowed to be displaced inward in the opposite direction, the inner needle 18 is further pulled out toward the proximal end side, so that the outer needle 18 is as shown in FIGS. The inner needle unit 12 is detached from the unit 14. That is, for example, by allowing the hinge pieces 102 and 104 to be displaced inward in the opposite direction, the hinge piece 102 that is upward when the indwelling needle assembly 10 is used moves downward due to the action of gravity, and the locking convexity is formed. The engagement between the portion 114 and the locking recess 40 is disengaged, and the inner needle unit 12 including the needle tip protector mechanism 58 can be detached from the outer needle unit 14.

Alternatively, since the base end side end edge portion of the locking recess 40 of the present embodiment is provided with an inclined surface 42b whose inner diameter dimension becomes smaller toward the base end side, it is fixed to the outer needle hub 30. By moving the member 62 to the base end side, the locking protrusions 114, 114 provided at the tips of the hinge pieces 102, 104 are separated from the locking recesses 40 inward in the opposite direction along the inclined surface 42b. Guided in the direction, the engagement between the locking protrusion 114 and the locking recess 40 may be disengaged. The guide surface (inclined surface) that guides the locking convex portion 114 in the direction of disengagement from the locking concave portion 40 is not the proximal end side edge portion of the locking concave portion 40, but the proximal end of the locking convex portion 114. It may be provided at the side edge portion. As a result, when the locking convex portion 114 is disengaged from the locking concave portion 40, the locking convex portion 114 is guided along the inclined surface provided on the base end side end edge portion, and the hinge pieces 102 and 104 face each other. It is displaced inward in the direction. Alternatively, such an inclined surface is provided on both the proximal end side edge portion of the locking recess 40 and the proximal end side edge portion of the locking convex portion 114, and the locking convex portion 114 from the locking concave portion 40 is provided. The hinge pieces 102 and 104 may be displaced inward in the facing direction by abutting the inclined surfaces on the surface of the hinge pieces 102 and 104.

In this way, after the indwelling needle assembly 10 is punctured, the inner needle unit 12 is detached from the outer needle unit 14, so that the outer needle unit 14 is indwelled on the patient's skin.

In the indwelling needle assembly 10 having the above structure, when the inner needle unit 12 and the outer needle unit 14 are assembled, the fixing member 62 constituting the needle tip protector mechanism 58 engages with the outer needle hub 30 from the inside. Since they are connected together, it is possible to avoid increasing the size of the indwelling needle assembly 10. Further, at the time of such assembly, the engaging pieces 86, 88 provided on the protector 60 engage with the engaging protrusions 112, 110 of the hinge pieces 104, 102 of the fixing member 62, so that the first and second engaging pieces 86, 88 are engaged with each other. The elastic pieces 66 and 68 are maintained in an elastically deformed state outward in the opposite direction. Therefore, it is avoided that the folded portions 82, 84 of the first and second elastic pieces 66, 68, particularly extending toward the inner needle 18, come into contact with the inner needle 18, and the inner needle 18 is pulled out when the inner needle 18 is pulled out. It is possible to prevent the first and second elastic pieces 66 and 68 from rubbing against each other and causing sliding resistance.

Further, when the protector 60 moves to the proximal end side with respect to the fixing member 62, the guide surface (the proximal end portions of the first and second elastic pieces 66, 68) provided on the proximal end portion of the protector 60 Since the outer surfaces 80 and 81 and the outer surfaces of the side plate portions 70 and 72) and the inner surface of the mounting hole 105 provided in the base end wall portion 100 of the fixing member 62 are brought into contact with each other and moved, the protector 60 and the fixing member are moved. It can be prevented that 62 and 62 move relative to each other in the direction perpendicular to the axis. As a result, the possibility that the user feels resistance when the inner needle 18 is pulled out and the protector 60 is moved to the proximal end side can be further reduced.

Furthermore, foldable portions 107 and 107 are provided on the proximal end side of the hinge pieces 102 and 104 of the fixing member 62 so that the tip ends of the hinge pieces 102 and 104 can be easily bent in a direction in which they approach each other. As a result, the engagement between the locking protrusions 114 and 114 provided at the tips of the hinge pieces 102 and 104 and the locking recess 40 provided on the inner surface 31a of the outer needle hub 30 is more stably realized. obtain.

Further, the engaging pieces 86, 88 protruding from the first and second elastic pieces 66, 68 are attached to the engaging protrusion 112 provided on the hinge piece 104 and the engaging protrusion 110 provided on the hinge piece 102. By engaging, the first and second elastic pieces 66 and 68 are held in an elastically deformed state outward in the opposite direction. At the same time, the engaging pieces 86 and 88 abut on the hinge pieces 102 and 104 from the inside, and the hinge pieces 104 and 102 are urged outward in the opposite direction via the engaging protrusions 112 and 110 to cause the hinge pieces. The inward displacement of 102 and 104 in the opposite direction is prevented. By adopting such a structure, the engaging pieces 86 and 88 have two functions of maintaining the shapes of the first and second elastic pieces 66 and 68 and preventing the hinge pieces 102 and 104 from being displaced. While the structure of the needle tip protector mechanism 58 is simplified, the protection operation of the needle tip 16 of the inner needle 18 can be stably performed.

Further, since the hemostatic valve mechanism 48 is housed and arranged in the outer needle hub 30 of the present embodiment, the leakage of blood at the time of pulling out the inner needle 18 is more reliably suppressed. Since the hemostatic valve mechanism 48 employs a pusher 52 that pushes open the slit 56 of the disc valve 50 by connecting a syringe or the like, communication and blocking of the fluid flow path are efficiently switched. Can be done.

Furthermore, when the inner needle unit 12 and the outer needle unit 14 are assembled, the tip end side of the needle tip protector mechanism 58 is inserted into the outer needle hub 30, and the base end side of the needle tip protector mechanism 58 is inserted into the inner needle hub 20. Will be inserted. As a result, the size of the outer needle hub and the inner needle hub can be avoided, and the size of the indwelling needle assembly 10 can be reduced as compared with the case where the entire needle tip protector mechanism is housed in the outer needle hub or the inner needle hub. Can be promoted.

Further, in the present embodiment, the base end side end edge portion of the locking recess 40 is an inclined surface 42b whose inner diameter dimension becomes smaller toward the base end side, and the inner needle unit 12 is separated from the outer needle unit 14. When the locking protrusions 114, 114 provided on the hinge pieces 102, 104 of the fixing member 62 move along the inclined surface 42b, the locking protrusions 114, 114 are separated from the locking recess 40. It is also possible to guide in the direction. As a result, when the inner needle unit 12 is detached from the outer needle unit 14, the inner needle unit 12 can be detached from the outer needle unit 14 only by pulling out the inner needle unit 12 in the axial direction with respect to the outer needle unit 14.

Next, FIG. 15 shows the indwelling needle assembly 120 as the second embodiment of the present invention, and FIGS. 16 (a) to 16 (d) constitute the indwelling needle assembly 120. The needle tip protector mechanism 122 is shown. In the first embodiment, in the fixing member (62), locking protrusions (114, 114) are provided at the tip portions of both of the pair of hinge pieces (102, 104) to lock the outer needle hub 30. Although it was locked in the recess 40, in the present embodiment, among the hinge pieces 126 and 128 located vertically opposed to each other in the fixing member 124, only the upper hinge piece 126 has a locking convex portion 130 as a locking portion. Is provided and is locked in the locking recess 40 of the outer needle hub 30. In the present embodiment, the members and parts substantially the same as those in the first embodiment are designated by the same reference numerals as those in the first embodiment in the drawings, and detailed description thereof will be omitted.

That is, the needle tip protector mechanism 122 of the present embodiment is composed of the protector 132 and the fixing member 124, and in the present embodiment, the protector 132 is configured to include one elastic piece 136 and is formed from the tip thereof. An engaging piece 140 as a regulating portion is projected laterally. In the present embodiment, the engaging piece 140 protrudes from the elastic piece 136 located below to the front side in FIGS. 16C and 16D.

On the other hand, also in the present embodiment, engaging protrusions 142 and 144 projecting from the circumferential end of one hinge piece 126 (128) toward the opposite hinge piece 128 (126) are formed. In the present embodiment, the engaging protrusion 142 projects downward from the upper hinge piece 126 on the front side in FIGS. 16 (c) and 16 (d), while the lower hinge piece 128 projects. On the front side in FIGS. 16A and 16B, the engaging protrusion 144 projects upward.

Here, in the present embodiment, a thin foldable portion 107 is provided at the base end portion of the upper hinge piece 126, and the upper hinge piece 126 bends in the vertical direction with respect to the base end wall portion 100. It is said to be easily deformed. On the other hand, the lower hinge piece 128 is not provided with a foldable portion (107), and the lower hinge piece 128 is made difficult to bend with respect to the base end wall portion 100.

Further, in the present embodiment, the axial dimension of the lower hinge piece 128 is smaller than that of the upper hinge piece 126, and particularly in the present embodiment, the axial dimension of the lower hinge piece 128 is the upper hinge piece. It is said to be about half of 126. An engaging protrusion 142 is formed in the axially intermediate portion of the upper hinge piece 126, while an engaging protrusion 144 is formed in the tip portion of the lower hinge piece 128. Further, the protruding height dimension of the engaging protrusion 144 is about half of the protruding height dimension of the engaging protrusion 142 on the opposite side. On the other hand, the protruding height dimension of the engaging protrusion 142 protruding toward the elastic piece 136 is formed so as to extend beyond the inner needle 18 to the elastic piece 136 side.

The needle tip protector mechanism 122 having such a structure is extrapolated to the inner needle 18. Then, in the initial state shown in FIG. 15 and the like, the tip portions of the protector 132 and the fixing member 124 are inserted from the proximal end side opening 34 of the outer needle hub 30.

Further, also in the indwelling needle assembly 120 of the present embodiment, in the initial state, as shown in FIGS. 16A to 16D, the engaging piece 140 protruding from the elastic piece 136 in the protector 132 is a hinge piece. It is sandwiched and supported in the vertical direction by 128 and an engaging protrusion 142 protruding from the hinge piece 126. Since the engaging piece 140 is urged inward in the opposite direction to the side of the protector 132, the hinge piece 126 is outward in the facing direction, that is, outside via the engaging protrusion 142. It is urged toward the inner surface 31a of the needle hub 30. In the present embodiment, the engaging piece 140 is supported by being sandwiched between the hinge piece 128 and the hinge piece 126 in the vertical direction, but the hinge piece 128 is bent with respect to the base end wall portion 100. Since it is difficult, the hinge piece 128 and the engaging piece 140 do not have to be engaged with each other. Further, the hinge piece 128 may not be provided, in which case the elastic piece 136 is configured to be close to the inner surface 31a of the outer needle hub 30. By doing so, a gap between the elastic piece 136 and the inner surface 31a of the outer needle hub 30 is sufficient to remove the locking convex portion 130 of the hinge piece 126 from the locking recess 40 of the inner surface 31a of the outer needle hub 30. It is possible to prevent the fixing member 124 from being detached from the outer needle hub 30 unless the elastic piece 136 moves inward.

As a result, the locking convex portion 130 provided at the tip of the hinge piece 126 is inserted into the locking recess 40 provided on the inner surface 31a of the outer needle hub 30 and locked, and the needle tip protector mechanism 122 and the needle tip protector mechanism 122 are engaged. The outer needle hub 30 is engaged. The hinge piece 128 is inserted inward from the base end side opening 34 of the outer needle hub 30, and the outer surface thereof may be in contact with the inner surface 31a of the outer needle hub 30, but the locking convex The portions 130 may face each other with a separation distance such that they cannot be separated from the locking recess 40.

Also in the indwelling needle assembly 120 of the present embodiment having the above-mentioned structure, the inner needle unit 12 is pulled out toward the base end side from the initial state shown in FIG. By engaging with the bottom wall portion 64 of the protector 132 and further pulling out the inner needle 18 toward the proximal end side, the protector 132 together with the inner needle 18 is moved toward the proximal end side with respect to the fixing member 124.

As a result, as shown in FIGS. 17A to 17D, when the engaging piece 140 passes through the engaging protrusion 142, the engaging piece 140 and the engaging protrusion 142 are engaged with each other. Is released. As a result, the elastic piece 136 is elastically deformed laterally (inwardly) according to the urging force to protect the needle tip (16) of the inner needle 18, and the urging to the hinge piece 126 is released. Inward deformation of the hinge piece 126 is allowed. In the present embodiment, the hinge piece 126 is bent and deformed inward according to the elastic force of the hinge piece 126 itself that tries to return to the initial shape. As a result, the engagement between the locking convex portion 130 and the locking concave portion 40 is disengaged, and the inner needle unit 12 can be disengaged from the outer needle unit 14. The hinge piece 126 has an elastic force of another elastic member assembled so as to generate an urging force, a gravitational action generated under an inward deformation allowable state of the hinge piece 126, or an inner needle unit 12. Further, the guide action of the inclined surface 42b in the locking recess 40 accompanying the pulling out to the base end side may be utilized so that the tilted surface 42b can be bent and deformed inward.

The indwelling needle assembly 120 in the present embodiment as described above can also exhibit the same effect as that in the first embodiment. In particular, as shown in the present embodiment, in the hinge pieces 126 and 128 of the fixing member 124, the locking convex portion 130 provided at the tip thereof may be provided only on one of them. Further, neither of the hinge pieces 126 and 128 needs to be bendable with respect to the base end wall portion 100, and only one hinge piece 126 need to be bendable. However, in the present embodiment, it is possible to grasp that the other hinge piece 128 including the base end wall portion 100 can be bent inward in the opposite direction with respect to one hinge piece 126, that is, at least one of them. It is sufficient that the hinge pieces 126 and 128 of the above are bendable inward in the facing direction, and it is not always necessary that the hinge pieces 126 and 128 are bendable with respect to the base end wall portion 100.

Although the embodiments of the present invention have been described in detail above, this is merely an example, and the present invention is not to be interpreted in any limited way by the specific description of the embodiments.

For example, in the second embodiment, the protector 132 is composed of only one elastic piece 136, but as in the first embodiment, the protector 132 may include two elastic pieces that face each other with the inner needle 18 in between. Often, the engaging piece extending from the elastic piece provided above in FIG. 15 may be engaged with the engaging protrusion 144 formed on the hinge piece 128. Further, when the protector includes a second elastic piece that faces the first elastic piece with the inner needle in between, the hinge piece 128 is eliminated, and the engaging piece extending from each elastic piece is the hinge piece 126. It may be engaged only with. That is, a guide groove for the engaging piece extending from the second elastic piece is formed in the hinge piece, and the engaging piece of the second elastic piece engages with the guide groove of the hinge piece 126 to form the first elastic piece. The engaging piece may be engaged with the inner surface of the hinge piece 126.

In the above embodiment, the protector 60 is provided with an elastic piece, but various protectors that move on the needle axis of the inner needle after being pulled out and protect the needle tip so as to prevent accidental puncture can be adopted. It is conceivable to move the protector on the needle axis of the inner needle by using gravity, elastic force, magnetic force, or the like.

However, when engaging the fixing member with the outer needle hub, in the above-described embodiment, a locking convex portion is adopted as a fixing portion provided on the outer surface of the fixing member, and a locking concave portion for locking with the locking convex portion is adopted. Is formed on the outer needle hub, but the mode of the fixing portion is not limited to this. That is, the fixing portion may be any one that positions the fixing member in the outer needle hub, and the friction increasing portion is provided at the tip of the hinge piece without providing the locking convex portion or the locking concave portion. The inner surface of the outer needle hub may come into contact with the fixing member and the outer needle hub may be engaged with each other due to the friction. Further, the locking convex portion may be a specification that is separate from the hinge piece and is fixed to the hinge piece. Further, the locking recess that engages with the locking protrusion may be provided in a configuration other than the inner surface of the outer needle hub. For example, it may be provided on the pusher guide. Furthermore, when the locking recess is provided on the inner surface of the outer needle hub, it is preferable that the distance from the base end of the outer needle hub is at least 7.5 mm or more.

Further, in the above-described embodiment, in the fixing members 62 and 124, hinge pieces 102, 104, 126 and 128 projecting from the base end wall portion 100 toward the tip end side are provided on both the upper and lower sides. It may be provided only in. That is, for example, in the above embodiment, the lower hinge pieces 104 and 128 are not indispensable, and only the upper hinge piece from the base end wall portion may extend toward the tip end side. In such an embodiment, for example, the engaging protrusion of the upper hinge piece engages with the engaging piece (regulating portion) of the lower elastic piece of the protector and is urged upward toward the inner surface side of the outer needle hub. The locking convex portion provided on the hinge piece of the outer needle hub is locked to the locking concave portion provided on the inner surface of the outer needle hub, and the lower elastic piece, particularly the portion bent in a dogleg shape, is outside. A structure may be adopted in which the needle hub abuts on the inner surface of the needle hub or is separated from the locking convex portion at a facing distance such that the locking convex portion cannot be separated from the locking concave portion.

In this case, the upper elastic piece may not be provided, but when the upper elastic piece is provided, for example, a mechanism for restricting the displacement of the upper elastic piece to the side (inward in the opposite direction) is upward. It may be provided on the hinge piece of. That is, for example, the upper hinge piece may be provided with a sideways L-shaped guide groove opened inward in the facing direction. By adopting such a structure, in the initial state, the engaging piece (regulating portion) provided on the upper elastic piece is inserted into the guide groove to be engaged and the displacement inward in the opposite direction is restricted. At the same time, when the inner needle is pulled out, the engaging piece moves in the axial direction along the guide groove by a predetermined distance, and then the elastic piece including the engaging piece moves in the opposite direction along the guide groove extending in the vertical direction. It can be displaced in the direction.

Further, in the above embodiment, the relative movement of the fixing members 62, 124 after use with respect to the protectors 60, 132 in the proximal direction is regulated by the engagement between the elastic projecting pieces 94, 96 and the recesses 106, 106. However, it may be regulated by the base end surface of the engaging protrusion and the engaging piece. The notch width formed at the base end of the engaging protrusion may be used as a guide groove for the engaging piece, and the relative displacement of the fixing member and the protector in the needle axis direction after use may not be possible for a predetermined amount or more.

Further, in the above-described embodiment, the tip shapes of the hinge pieces 102, 104, 126, and 128 are substantially curved plates having a circumferential dimension of less than half a circumference, but a substantially curved plate having a circumferential dimension of more than half a circumference. It may be in shape. Further, the tip shape of the hinge piece may be a shape other than a substantially curved plate shape such as a plate shape having a U-shaped cross section. Furthermore, in the above-described embodiment, the engaging pieces 86, 88, 140 that engage with the engaging protrusions 110, 112, 142, 144 are merely laterally extending portions, but sandwich the inner needle. It may be configured to project to one side of the facing hinge, and the protruding height may be a height that extends beyond the inner needle to one side of the facing hinge.

Further, the engaging piece or the engaging protrusion in the above embodiment may be coated or shaped so as to reduce the sliding resistance between the engaging piece and the engaging protrusion.

In addition, each member such as a fixing member and a protector may be integrally manufactured by integral molding or the like, or may be manufactured as a separate partial configuration and then assembled to form an integral member. Further, although this safety mechanism is preferably used for an indwelling needle for puncturing a blood vessel, it may be used for an indwelling needle for puncturing a subcutaneous port, and if the specification is such that the inner needle is pulled out from the outer needle, this safety mechanism is effective. Used for.

Further, in the above embodiment, the elastic pieces 66, 68, 136 engage with the engaging protrusions 86, 88, 142 provided on the hinge pieces 102, 104, 126 to move laterally (inwardly). Displacement was regulated, but for example, by engaging an elastic piece with a member formed integrally with or separately from the hinge piece, the displacement of the elastic piece to the side (inward) is regulated. It may be.

10,120: Indwelling needle assembly, 16: Needle tip, 18: Inner needle, 20: Inner needle hub, 28: Outer needle, 30: Outer needle hub, 31a: Inner surface, 34: Base end side opening, 40: Locking recess, 42b: Inclined surface, 50: Disc valve (valve body), 52: Pusher, 60, 132: Protector, 62, 124: Fixing member, 66: First elastic piece, 68: Second elasticity Piece, 70, 72: Side plate part (guide surface), 76: Insertion hole, 80, 81: Outer surface (guide surface), 86, 88, 140: Engagement piece (regulatory part), 102, 104, 126, 128: Hinge piece, 105: Mounting hole, 107: Folding part, 110, 112, 142, 144: Engagement protrusion, 114, 130: Locking convex part (locking part), 136: Elastic piece

Claims (9)

An inner needle having an inner needle hub on the base end side is inserted into an outer needle having an outer needle hub on the base end side so as to be retractable, and the needle tip of the inner needle pulled out from the outer needle is protected. In an indwelling needle assembly with a protector
The protector includes an elastic piece that extends toward the needle tip side of the inner needle and is urged toward the side.
A fixing member having a hinge piece extending toward the needle tip side of the inner needle and having a tip portion locked to the inner surface of the outer needle hub is assembled to the protector so as to be movable in the axial direction.
By engaging the restricting portion provided on the elastic piece with the hinge piece, the lateral movement of the elastic piece is restricted, and the elastic piece causes the hinge piece to be attached to the outer needle hub. It is fixed and held against the inner surface,
By pulling out the inner needle from the outer needle, the protector is locked to the inner needle and moves relative to the fixing member, so that the elastic piece engages the regulating portion with the hinge piece. When released, the elastic piece of the protector moves laterally to cover the needle tip of the inner needle, and the hinge piece of the fixing member is allowed to move inward in the radial direction of the outer needle hub. An indwelling needle assembly characterized in that the fixing member is allowed to be detached from the outer needle hub. In a state where the hinge piece is fixedly held with respect to the inner surface of the outer needle hub,
The indwelling needle assembly according to claim 1, wherein the elastic piece is held in a non-contact state with the inner needle. The hinge piece of the fixing member is formed with an engaging protrusion that is provided so as to sandwich the inner needle and projects toward the elastic piece side.
By pulling out the inner needle from the outer needle, the restricting portion of the elastic piece moves from the engaging protrusion to the proximal end side, so that the elastic piece moves laterally to cover the needle tip. The indwelling needle assembly according to claim 1 or 2. The hinge piece of the fixing member is provided with a locking portion with respect to the inner surface of the outer needle hub at the tip portion in the length direction extending toward the needle tip side, and is provided with a circumferential end in the middle portion in the length direction. An engaging protrusion protruding from the edge is formed,
The indwelling needle assembly according to any one of claims 1 to 3, wherein the restricting portion of the elastic piece is engaged with the engaging protrusion. The elastic piece of the protector is provided with an engaging piece that projects laterally to form the restricting portion, and the engaging piece is engaged with the hinge piece of the fixing member. The indwelling needle assembly according to any one of claims 1 to 4. In the outer needle hub, a valve body and a pusher that pushes the valve body open from the base end side are incorporated in a housed state, and at the same time.
The indwelling needle assembly according to any one of claims 1 to 5 , wherein the tip end portion of the hinge piece in the fixing member extends from the base end side of the outer needle hub to the outer circumference of the pusher. Three-dimensional. The fixing member is formed with a hinge piece extending from both side edges of a base end portion attached to the protector toward the needle tip side of the inner needle, and on the base end side of the hinge piece. The indwelling needle assembly according to any one of claims 1 to 6, wherein a folding portion that allows bending in opposite directions is provided. The hinge piece is engaged with the restricting portion in a state of being urged toward the side.
The indwelling needle assembly according to any one of claims 1 to 7 , wherein the hinge piece automatically moves in the inner diameter direction of the outer needle hub when the engagement between the hinge piece and the regulating portion is released. .. An inner needle having an inner needle hub on the base end side is inserted into an outer needle having an outer needle hub on the base end side so as to be pullable, and is on the needle shaft of the inner needle pulled out from the outer needle. In an indwelling needle assembly with a moving protector
A fixing member having a fixing portion on the outer surface is provided on the outside of the protector in the outer needle hub, and the protector is provided with an engaging piece that projects laterally toward the outside.
The engaging piece of the protector is brought into contact with the fixing member to restrict lateral movement of the engaging piece, and the fixing member is moved inward in the radial direction of the outer needle hub. Is blocked and the fixing member is positioned within the outer needle hub.
By pulling out the inner needle from the outer needle, the protector is locked to the inner needle, and the inner needle and the protector move relative to the fixing member, so that the protector moves laterally. As well as moving on the needle axis of the inner needle, the fixing member is allowed to move inward in the radial direction of the outer needle hub, and the fixing member is allowed to separate from the outer needle hub. An indwelling needle assembly characterized by being

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