JP7470292B2 - Indwelling needle assembly and medical valve - Google Patents

Description

The present invention relates to an indwelling needle assembly and a medical valve equipped with an elastic valve body.

Conventionally, indwelling needle assemblies have been known as medical tools used in procedures such as infusion, blood sampling, and hemodialysis. An example of this indwelling needle assembly is the one described in JP 2012-517326 A (Patent Document 1). The indwelling needle assembly described in Patent Document 1 has a structure in which an elastic valve body is attached to an outer needle hub and an inner needle is inserted through the elastic valve body. The elastic valve body can prevent leakage of blood that has flowed back into the outer needle hub by withdrawing the inner needle after puncturing with the indwelling needle assembly.

Incidentally, in the indwelling needle assembly described in Patent Document 1, a member (a partition actuation member) is provided within the outer needle hub for opening the slit in the elastic valve body when the male connector is connected.

JP 2012-517326 A

The problem to be solved by the present invention is to provide an indwelling needle assembly and a medical valve with a novel structure that allows the slit in the elastic valve body to open when the male connector is connected without providing a special component inside the outer needle hub.

Below, we will describe aspects of the present invention that have been made to solve these problems. Note that the components employed in each aspect described below can be used in any combination possible.

The first aspect of the present invention is an indwelling needle assembly in which an inner needle is inserted into an elastic valve body which is attached to an outer needle hub and consists of a disk valve which is made of a disk-shaped elastic body as a whole and has a slit formed therethrough from the front to the back, characterized in that inner locking claws and outer locking claws provided at the base end of the outer needle hub are engaged with inner locking grooves and outer locking grooves formed on the outer periphery of the elastic valve body, and the elastic valve body is compressed in the radial direction by at least one of the inner locking claws and the outer locking claws.

With an indwelling needle assembly constructed in accordance with this embodiment, the slit can be opened and closed by directly inserting and removing the male connector into the elastic valve body.

In addition, in the indwelling needle assembly according to this embodiment, the elastic valve body is compressed in the radial direction by at least one of the inner and outer locking claws, which improves the support force of the elastic valve body and improves the liquid-tightness of the elastic valve body. Therefore, in this embodiment in which the elastic valve body is located at the base end of the outer needle hub, it is possible to prevent blood from adhering to the user, etc., due to a decrease in liquid-tightness when the inner needle is removed, which may be caused by, for example, heat history due to sterilization processing while the inner needle is inserted into the elastic valve body, or by the inner needle being inserted for a long period of time.

The second aspect of the present invention is an indwelling needle assembly according to the first aspect, in which the elastic valve body is compressed in the radial direction by the outer locking claw.

The indwelling needle assembly constructed in accordance with this aspect can effectively prevent the slit in the elastic valve body from being unintentionally opened outward by blood that has flowed into the outer needle hub.

A third aspect of the present invention is an indwelling needle assembly according to the first or second aspect, in which the outer surface of the outer needle hub and the outer surface of the elastic valve body are connected by a smooth surface.

The indwelling needle assembly constructed in accordance with this embodiment makes it easy to treat the outer surface of the elastic valve body. For example, before and after connecting the male connector, the outer surface of the elastic valve body can be easily disinfected by wiping it with a cloth or cotton soaked in alcohol or the like.

In a fourth aspect of the present invention, in the indwelling needle assembly according to any one of the first to third aspects, an air vent passage is formed that connects the internal region of the outer needle hub, located on the tip side of the elastic valve body, to the outside, and a filter that allows the passage of gas but prevents the passage of liquid is disposed at a position in the air vent passage away from the opening to the internal region.

With an indwelling needle assembly constructed according to this embodiment, of the blood that has flowed into the outer needle hub, only the blood that has flowed into the air vent passage, which has a small cross-sectional area, comes into contact with the filter. This keeps the amount of blood that comes into contact with the filter to a minimum, preventing a decrease in the filter's ventilation function and blood leakage due to contact with liquid.

The fifth aspect of the present invention is an indwelling needle assembly according to the fourth aspect, in which the air vent passage extends toward the tip side.

With an indwelling needle assembly constructed in accordance with this aspect, for example, the filter can be positioned sufficiently away from the internal region without increasing the diameter of the outer needle hub, making it difficult for blood to come into contact with the filter.

In a sixth aspect of the present invention, in the indwelling needle assembly according to the fifth aspect, the elastic valve body is provided with a tip support part that extends toward the tip side on the outer circumferential side of the inner locking groove and the outer locking groove, and the air vent passage that extends toward the tip side is formed between the inner surface of the tip support part and the outer needle hub.

With an indwelling needle assembly constructed according to this aspect, an air vent passage extending toward the tip can be formed by making good use of the tip support portion that extends toward the tip of the elastic valve body.

The seventh aspect of the present invention is an indwelling needle assembly according to any one of the fourth to sixth aspects, in which a radial through hole is formed in the portion of the outer needle hub where the inner locking claw is formed, and the air vent passage is configured to include the through hole.

The indwelling needle assembly constructed according to this embodiment employs an effective support structure for the elastic valve body using the inner locking claws, while allowing a stable air exhaust path to be formed in the internal region of the outer needle hub through the air vent passage.

The eighth aspect of the present invention is an indwelling needle assembly according to any one of the fourth to seventh aspects, in which the filter is disposed inside the outer needle hub.

An indwelling needle assembly constructed in accordance with this embodiment can effectively prevent, for example, the filter from being deformed by touching it from the outside, causing blood to leak, or blood from adhering to the user's fingers by touching a filter that has come into contact with blood from the outside.

The ninth aspect of the present invention is an indwelling needle assembly according to any one of the first to eighth aspects, in which the outer needle hub is configured to include an outer housing having the outer locking claw and an inner housing having the inner locking claw, and multiple members including the outer housing and the inner housing are fixed by a concave-convex fit.

With an indwelling needle assembly constructed according to this embodiment, the fixing structure can be simplified compared to fixing by ultrasonic welding or the like, and it is also possible to avoid increasing the diameter of the outer needle hub. In particular, by making the outer locking claw and the inner locking claw separate members, it is also possible to easily assemble the elastic valve body to the outer needle hub.

A tenth aspect of the present invention is a medical valve in which a disk-shaped elastic valve body is attached and a port for connecting a male connector is provided, and in which inner and outer claws formed on a housing are engaged and supported by inner and outer locking grooves formed on the outer periphery of the elastic valve body, wherein an air vent passage connecting an internal area of the port for connecting a male connector into which fluid can flow , to the outside is formed including a radial through hole provided in the part of the housing where the inner claws are formed, and a filter which allows the passage of gas but prevents the passage of liquid is arranged on the air vent passage and communicates with the internal area via the air vent passage.

A medical valve constructed according to this embodiment can simultaneously support the elastic valve body with the inner and outer claws and expel air through the air vent passage. In addition, because only the liquid that has flowed into the air vent passage comes into contact with the filter, the amount of liquid that comes into contact with the filter can be kept small, and the filter can effectively prevent liquid leakage.

The indwelling needle assembly constructed according to the present invention allows the slit in the elastic valve body to be opened when the male connector is connected without the need for a special member for opening the slit in the outer needle hub. Furthermore, the medical valve constructed according to the present invention can exhibit excellent gas discharge properties in addition to excellent retention force in the elastic valve body.

FIG. 1 is a longitudinal cross-sectional view showing an indwelling needle assembly according to an embodiment of the present invention. FIG. 2 is a longitudinal cross-sectional view showing a main part of the indwelling needle assembly shown in FIG. 1 . FIG. 2 is a perspective view showing an elastic valve body that constitutes the indwelling needle assembly shown in FIG. 1 . FIG. 4 is a longitudinal sectional view of the elastic valve body shown in FIG. 3 . FIG. 2 is a perspective view showing a state in which the inner needle has been removed from the indwelling needle assembly shown in FIG. 1 . FIG. 6 is a longitudinal sectional view of FIG. 6 is a longitudinal cross-sectional view showing the state in which a male connector is connected to the outer needle hub shown in FIG. 5 . FIG. 2 is a longitudinal cross-sectional view showing a medical valve according to another embodiment of the present invention.

In order to clarify the present invention more specifically, the following embodiment of the present invention will be described in detail with reference to the drawings.

1 and 2 show an indwelling needle assembly 10 according to one embodiment of the present invention. This indwelling needle assembly 10 includes an inner needle unit 12 and an outer needle unit 14, and is configured by inserting the inner needle unit 12 into the outer needle unit 14. In the following description, the axial direction refers to the left-right direction in FIG. 1. The tip side refers to the left side in FIG. 1, and the base side refers to the right side in FIG. 1.

More specifically, the inner needle unit 12 is configured to include an inner needle 18 having a needle tip 16 at its distal end, and an inner needle hub provided on the proximal end side of the inner needle 18. The inner needle 18 is a hollow needle made of a known material, such as stainless steel, aluminum, titanium, or an alloy thereof, and the needle tip 16 at its distal end is sharp. However, the inner needle 18 may also be a solid needle. The shape of the inner needle hub is not shown in the figures, as any known shape may be used.

The outer needle unit 14 is configured to include an outer needle 20 and an outer needle hub 22 provided on the base end side of the outer needle 20. The outer needle 20 is tubular and is formed from a material having appropriate flexibility, such as various soft resins such as ethylene-tetrafluoroethylene copolymer (ETFE), polyurethane, and polyether nylon resin. The outer peripheral surface of the tip portion of the outer needle 20 is a tapered outer peripheral surface 24 that tapers to a narrower point, which can reduce the puncture resistance to the living body. In addition, by providing a through hole in the peripheral wall of the tip portion of the outer needle 20, it is also possible to improve the flow efficiency of fluid through the outer needle 20.

Furthermore, the outer needle hub 22 has a generally cylindrical shape extending in the axial direction as a whole. The outer needle hub 22 of this embodiment is composed of multiple members, and is composed of three parts: a base member 26, an internal housing 28, and an external housing 30, all of which are generally cylindrical. It is preferable that the base member 26, the internal housing 28, and the external housing 30 are all formed from a hard synthetic resin.

This base member 26 is generally cylindrical and extends in the axial direction as a whole, with the axial middle portion extending generally straight with a generally constant thickness dimension, while the tip portion is a tapered portion 32 with a generally constant thickness dimension and a smaller diameter dimension toward the tip. A crimping pin 34 is fixed to the inner peripheral surface of this tapered portion 32, and the base end of the outer needle 20 is sandwiched and supported between the tapered portion 32 and the crimping pin 34, and is fixed with an adhesive or the like as necessary. As a result, the outer needle hub 22 is fixedly provided on the base end side of the outer needle 20.

On the other hand, a bulge 36 that protrudes outward is formed at the base end of the base member 26, and in this embodiment, it is formed around the entire circumference in the circumferential direction with a substantially semicircular cross-sectional shape. The outer peripheral surface of this bulge 36 is provided with an engagement claw 38 that protrudes outward. In this embodiment, a pair of engagement claws 38 are provided on both sides in one radial direction (both up and down sides in FIG. 1) on the outer peripheral surface of the base member 26, and each engagement claw 38 has a predetermined circumferential dimension and is substantially rectangular in plan view. The outer peripheral surface of this engagement claw 38 is an inclined surface 40 that inclines outward toward the tip. On the other hand, the tip end surface of the engagement claw 38 is a flat surface 41 that extends in the axial direction.

In addition, on the outer peripheral surface of the base member 26, positioning protrusions 42, 42 (see FIG. 5) are provided extending from the bulge 36 toward the base end in a direction perpendicular to the opposing direction of the engagement claws 38, 38 (perpendicular to the plane of the paper in FIG. 1).

The base end of the base member 26 has an even smaller outer diameter, and an annular step surface 44 is formed in the portion adjacent to the base end side of the engagement claw 38. A generally cylindrical insert portion 46 having an outer diameter smaller than that of the bulge portion 36 is provided on the base end side of the step surface 44, and the insert portion 46 is inserted into a generally cylindrical filter 108 described below. Furthermore, an annular support portion 48 that protrudes toward the base end side is formed in the radially intermediate portion of the base end side end face of the insert portion 46.

The internal housing 28 is generally cylindrical and extends in the axial direction. A ring-shaped receiving seat 50 is formed at the base end of the internal housing 28, with a gooseneck-shaped bent cross section that narrows toward the inner circumference. An inner locking claw 52 is formed on the inner periphery of the receiving seat 50 as a ring-shaped inner claw that protrudes toward the base end. In this embodiment, the inner peripheral surface of the inner locking claw 52 is a curved surface 54 that is convex toward the inner circumference as a whole. The curved surface 54 does not need to be curved over the entire surface, and may have a flat portion, for example.

On the other hand, the tip of the internal housing 28 is provided with an annular tip portion 56 that protrudes outward with a substantially constant thickness dimension (axial direction).

Here, a through hole 58 is formed in the axially middle portion of the inner locking claw 52, penetrating in the radial direction. In this embodiment, a pair of through holes 58, 58 are formed in the annular inner locking claw 52, facing each other in the radial direction, at circumferential positions corresponding to the engaging claws 38, 38 of the base member 26, and the inside and outside of the internal housing 28 are connected to each other through the through holes 58, 58.

In addition, a communication groove 60 is formed on the outer peripheral surface of the internal housing 28, extending over substantially the entire length in the axial direction. This communication groove 60 is, for example, a groove with a rectangular cross section that opens to the outer peripheral side, and extends continuously from the tip portion of the outer peripheral opening of the through hole 58 to the tip side, and further opens to the tip end face of the annular tip portion 56 through the base end face and outer peripheral surface of the annular tip portion 56. In this embodiment, the communication groove 60 is formed at a circumferential position corresponding to the through hole 58, and a pair of communication grooves 60, 60 are formed facing each other in the radial direction.

The outer housing 30 is generally cylindrical and includes a peripheral wall portion 62 that extends in the axial direction. The inner and outer diameters of the peripheral wall portion 62 are larger at the tip end than at the base end, and the thickness is also larger. A male thread portion 64 is provided on the outer peripheral surface at the base end of the peripheral wall portion 62, allowing a luer lock type male connector to be connected to the outer housing 30 (outer needle hub 22).

On the other hand, the inner peripheral surface at the base end of the peripheral wall portion 62 is provided with a base end wall portion 66 in the shape of a ring protruding toward the inner peripheral side, and an outer locking claw 68 is formed on the inner peripheral edge of the base end wall portion 66 as an outer claw portion that is folded back inward in the axial direction and protrudes toward the tip side. In this embodiment, the outer locking claw 68 is formed in a ring shape over the entire circumference in the circumferential direction. In particular, in this embodiment, the inner diameter dimension A (see FIG. 2) of the outer locking claw 68 is smaller than the inner diameter dimension B (see FIG. 2) of the inner locking claw 52, and when the internal housing 28 and the external housing 30 are assembled, the inner peripheral surface of the outer locking claw 68 is located on the inner peripheral side of the inner peripheral surface (curved surface 54) of the inner locking claw 52. Furthermore, on the outer peripheral side of the outer locking claw 68, an outer retaining groove 70 that extends in the circumferential direction with a predetermined width in the radial direction is formed as an annular groove that opens to the tip side.

In addition, in this embodiment, an inclined surface 72 that gradually expands in the axially inward direction is provided on the inner peripheral surface at the protruding tip (axially inner end) of the outer locking claw 68, and in this embodiment in particular, the inclined surface 72 is a tapered surface having a substantially constant inclination angle. As described below, when the inner housing 28 and the outer housing 30 are assembled to each other, the inner locking claw 52 and the outer locking claw 68 face each other in the axial direction at the base end of the outer needle hub 22, and the curved surface 54, which is the inner peripheral surface of the inner locking claw 52, is located on the axially inward extension of the tapered surface (inclined surface) 72.

Furthermore, a through window 74 is formed at the tip of the peripheral wall 62 of the external housing 30, penetrating in the thickness direction (radial direction). This through window 74 is circumferentially positioned and shaped to correspond to the engagement claws 38 of the base member 26, and is provided as a pair facing each other in the radial direction (up and down direction in FIG. 1), and is generally rectangular in plan view. In addition, a notch 76 is formed in the peripheral wall 62, corresponding to the positioning protrusion 42 of the base member 26. In this embodiment, a pair of notches 76, 76 (see FIG. 5) extending from the tip of the peripheral wall 62 toward the base end are formed on both sides in a direction perpendicular to the facing direction of the through windows 74, 74.

The base member 26, the inner housing 28, and the outer housing 30 having the above-described structure are assembled to form the outer needle hub 22, and an elastic valve body 78 is attached to the outer needle hub 22. Specifically, in the outer needle hub 22, the elastic valve body 78 is sandwiched and supported between the inner housing 28 and the outer housing 30.

3 and 4 show the elastic valve body 78 in a separate state before being assembled to the outer needle hub 22. The elastic valve body 78 in this embodiment is generally disk-shaped and is made of an elastic material such as rubber or elastomer. A slit 82 is formed in the central portion 80 of the elastic valve body 78, penetrating in the thickness direction. In this embodiment, the slit 82 is linear (straight-line shaped), but the shape of the slit 82 is not limited in any way and may be cross-shaped or extend radially from the center. In addition, in this embodiment, the slit 82 with a width dimension of approximately 0 is provided in the elastic valve body 78 in a separate state, but a through hole such as a circle or rectangle having a certain width dimension may be provided in the elastic valve body in a separate state, and the elastic valve body may be attached to the outer needle hub in a radially compressed state, thereby forming a slit (through hole) with a width dimension of approximately 0.

The elastic valve body 78 is provided on its outer periphery with a cylindrical support portion 84 that protrudes inward and outward in the axial direction, and the central portion 80 and the cylindrical support portion 84 are connected by an annular connecting portion 86 that extends around the entire circumference in the circumferential direction. As a result, in this embodiment, the elastic valve body 78 is formed as a one-piece molded product.

The annular connecting portion 86 is formed by making the thickness dimension smaller than that of the central portion 80 of the elastic valve body 78. In this embodiment, an inner locking groove 88 and an outer locking groove 90 are formed on the outer peripheral portion of the axial inner surface side and the outer surface side of the elastic valve body 78, respectively, and the annular connecting portion 86 is formed between the axial distance between the bottoms of the two locking grooves 88, 90. That is, in this embodiment, the central portion 80 of the elastic valve body 78 is configured to include an inner protrusion 92 (the portion axially inward from the lower two-dot chain line in FIG. 4) that protrudes axially inward from the groove bottom surface of the inner locking groove 88, and an outer protrusion 94 (the portion axially outward from the upper two-dot chain line in FIG. 4) that protrudes axially outward from the groove bottom surface of the outer locking groove 90. In this embodiment, a recessed groove portion 96 that extends continuously around the entire circumference is formed on the wall portion on the inner peripheral side of the inner locking groove 88.

The cylindrical support portion 84 connected to the outer periphery of the annular connecting portion 86 is configured to include a base end support portion 98 that protrudes axially outward (base end side) from the annular connecting portion 86, and a tip end support portion 100 that protrudes axially inward (tip side). In this embodiment, the base end support portion 98 protrudes toward the base end with a dimension that does not reach the base end face of the central portion 80, while the tip end support portion 100 protrudes toward the tip side by a dimension that is greater than the tip end face of the central portion 80.

The outer needle hub 22 is formed by the base member 26, the internal housing 28, and the external housing 30 having the above-described structure, and the elastic valve body 78 as described above is attached to the base end opening 102 of the outer needle hub 22. As a result, as described below, by inserting a syringe 110 from the base end opening 102 of the outer needle hub 22, the tip portion of the syringe 110 directly pushes open the elastic valve body 78, opening the slit 82. Note that the elastic valve body does not need to be provided at the very base of the outer needle hub, and it is sufficient that it is located at the base end of the outer needle hub to the extent that it is directly pushed open by the male connector (syringe) when the male connector is inserted.

Here, when attaching the elastic valve body 78 to the outer needle hub 22, first, the base member 26 and the internal housing 28 are fitted together so that the inner circumferential surface at the tip portion of the internal housing 28 is overlapped with the annular support portion 48 at the base end of the base member 26. If necessary, the base member 26 and the internal housing 28 may be fixed by means of adhesion, welding, or the like. Then, the elastic valve body 78 is overlapped with the internal housing 28, and the inner locking claw 52 of the internal housing 28 is pressed into the inner locking groove 88 of the elastic valve body 78 so as to be engaged. In this embodiment, only the protruding tip portion of the inner locking claw 52 is inserted into the inner locking groove 88, so that the through hole 58 provided in the inner locking claw 52 is not blocked by the elastic valve body 78.

In addition, in this embodiment, a concave groove portion 96 is provided on the inner circumferential side of the inner locking groove 88, so that the inner circumferential surface (curved surface 54) of the inner locking claw 52 and the inner circumferential surface of the concave groove portion 96 are radially separated from each other. As a result, in the initial state of the indwelling needle assembly 10 shown in Figures 1 and 2, the inner circumferential surface (curved surface 54) of the inner locking claw 52 is not covered by the elastic valve body 78 except for the protruding tip portion inserted into the inner locking groove 88, and is exposed to the inner region 104, which is the region on the tip side of the elastic valve body 78 in the outer needle hub 22. As a result, in the initial state, the opening 105 on the inner circumferential side of the through hole 58 provided in the inner locking claw 52 is open to the inner region 104 of the outer needle hub 22.

In this state, the external housing 30 is overlapped from the axial outside, and the base member 26 and the external housing 30 are moved in a direction approaching each other. As a result, the positioning protrusion 42 of the base member 26 is fitted into the notch 76 in the external housing 30, and the engagement claw 38 of the base member 26 is engaged with the through window 74 of the external housing 30. In particular, in this embodiment, the notch 76 is provided at the tip of the peripheral wall portion 62 of the external housing 30, so that the tip of the peripheral wall portion 62 is easily bent, and further, the engagement claw 38 is provided with an inclined surface 40, so that the engagement claw 38 is easily engaged with the through window 74 due to the guiding action of the inclined surface 40. As a result, in this embodiment, the base member 26 and the external housing 30 are fixed by the uneven engagement of the engagement claw 38 and the through window 74 without being bonded or welded, but instead of or in addition to such a locking structure using the engagement claw, the base member 26 and the external housing 30 may be fixed by adhesion or welding. Alternatively, the base member 26 and the internal housing 28 may be fixed by a concave-convex fit, or the internal housing 28 and the external housing 30 may be fixed by a concave-convex fit. Therefore, it is not necessary for all of the multiple members constituting the outer needle hub 22 to be fixed without bonding or welding, and for example, at least two members may be fixed by a concave-convex fit.

Then, by fixing the base member 26 and the outer housing 30 in this way, the outer locking claws 68 of the outer housing 30 are pressed into the outer locking grooves 90 of the elastic valve body 78 so as to be engaged. As a result, the outer protrusion 94 of the elastic valve body 78 is inserted into the inner circumferential side of the outer locking claws 68, and in this embodiment, the outer surface of the outer needle hub 22 (the base end surface 66a of the base end wall portion 66 of the outer housing 30) and the outer surface of the elastic valve body 78 (the base end surface 80a of the central portion 80) are connected by a smooth surface. In particular, in this embodiment, both outer surfaces 66a, 80a are located on approximately the same plane. As a result, the annular connecting portion 86 of the elastic valve body 78 is supported by being sandwiched from both sides in the axial direction by the axially inner and outer locking claws 52, 68.

The base end support portion 98 of the cylindrical support portion 84 is fitted into the outer retaining groove 70 of the outer housing 30, and the base end surface of the annular tip portion 56 of the inner housing 28 and the tip end surface of the tip support portion 100 of the cylindrical support portion 84 are abutted against each other, so that the cylindrical support portion 84 is supported by being sandwiched between the base end wall portion 66 of the outer housing 30 and the annular tip portion 56 of the inner housing 28 in the axial direction, and is preferably compressed in the axial direction. The tip support portion 100 of the cylindrical support portion 84 is also sandwiched between the inner housing 28 and the outer housing 30 in the radial direction. In this way, the tip support portion 100 is sandwiched and supported between the inner housing 28 and the outer housing 30 in the radial direction, so that the outer peripheral opening of the communication groove 60 provided on the outer peripheral surface of the inner housing 28 is covered with the inner surface of the tip support portion 100 to form a tunnel-like passage.

One end of the tunnel-shaped passage in the longitudinal direction is connected to an internal region 104 on the distal side of the elastic valve body 78 in the outer needle hub 22 through a through hole 58 provided in the inner locking claw 52, and the other end of the tunnel-shaped passage in the longitudinal direction is open to the distal end face of the annular distal end portion 56 in the inner housing 28, and is connected to the external space through the through window 74 from the space between the outer housing 30 and the base member 26. Therefore, in this embodiment, an air vent passage 106 is formed that includes the through hole 58 and the tunnel-shaped passage (communication groove 60) and connects the internal region 104 on the distal side of the elastic valve body 78 in the outer needle hub 22 to the outside. As a result, the air vent passage 106 extends from the internal region 104 toward the distal side.

Here, a filter 108 is disposed on the air vent passage 106. This filter 108 has the property of allowing the passage of gas and preventing the passage of liquid. The filter 108 is not limited in any way as long as it has the above-mentioned properties, but for example, a sintered porous body formed by sintering a polymer material such as polyethylene with a material containing a hydrophilic, water-soluble or water-swellable polymer, a hydrophobic nonwoven fabric, a porous body, etc. can be suitably used. In particular, when a sintered body containing a highly water-absorbent polymer (SAP) is used as the filter 108, it allows gas to pass in the initial state until moisture comes into contact with the filter 108, and when moisture comes into contact with the filter 108, it reacts with water (absorbs moisture) and swells, preventing the passage of gas. This improves the pressure resistance of the liquid seal and allows a stable blood leakage prevention effect to be exerted.

The filter 108 of this embodiment is provided on the air vent passage 106 at a position separated from the opening 105 to the internal region 104 of the through hole 58 without being exposed to the internal region 104 of the outer needle hub 22. In particular, in this embodiment, the filter 108 is provided inside the outer needle hub 22, specifically, provided on the distal side of the internal housing 28, and is continuous with the communication groove 60 (tunnel-shaped passage) that opens to the distal end face of the internal housing 28 (the distal end face of the annular distal portion 56), and is provided radially between the external housing 30 and the base member 26. As a result, the filter 108 is in communication with the internal region 104 of the outer needle hub 22 through the communication groove 60 (tunnel-shaped passage).

Furthermore, in this embodiment, the filter 108 is substantially cylindrical and is fitted to the inserting portion 46 of the base member 26. The tip end face of the filter 108 abuts against the step surface 44 of the base member 26, and the base end portion of the filter 108 is compressed radially between the inner peripheral surface of the outer housing 30 and the outer peripheral surface of the inserting portion 46. The base end face of the filter 108 does not need to abut against the tip end face of the inner housing 28 (the tip end face of the annular tip portion 56), and may have a gap in the axial direction, or may abut against the tip end face of the inner housing 28 and be compressed in the axial direction with the step surface 44. Furthermore, at the tip portion of the filter 108, the inner diameter dimension of the outer housing 30 is made large, and a gap is provided between the filter 108 and the inner peripheral surface of the outer housing 30, improving manufacturing efficiency.

The indwelling needle assembly 10 of this embodiment is constructed by inserting the inner needle unit 12 into the outer needle unit 14 constructed as described above. Specifically, the inner needle 18 is inserted into the elastic valve body 78, and the needle tip 16 of the inner needle 18 protrudes from the tip of the outer needle 20. Then, after puncturing the blood vessel with the inner needle 18 and the outer needle 20 overlapping with each other, the inner needle 18 is pulled out of the outer needle unit 14, so that the outer needle unit 14 is retained in the patient's blood vessel while being punctured, as shown in Figures 5 and 6.

Here, in the elastic valve body 78 in a single item state, the outer diameter dimension C (i.e., the outer diameter dimension of the outward protrusion 94) of the central portion 80 (see FIG. 4) is larger than the inner diameter dimension A of the outer locking claw 68 of the outer needle hub 22. As a result, when the elastic valve body 78 is assembled to the outer needle hub 22, the base end side of the central portion 80, i.e., the outward protrusion 94, is compressed in the radial direction by the outer locking claw 68. As a result, even if the state in which the inner needle 18 is inserted into the elastic valve body 78 is maintained for a long period of time, or even if heat is applied with the inner needle 18 inserted into the elastic valve body 78, the slit 82 of the elastic valve body 78 can be stably closed when the inner needle 18 is removed, as shown in FIG. 6.

In addition, as the inner needle 18 is removed, the internal region 104 of the outer needle hub 22 is filled with blood that has flowed in through the outer needle 20. This allows air in the internal region 104 to be discharged to the external space through the air vent passage 106, preventing air from entering the patient's body when connecting the male connector (syringe 110) described below. Furthermore, a groove portion 96 is provided adjacent to the opening on the inner circumference side of the air vent passage 106, so that the groove portion 96 can also provide an air guiding effect. Furthermore, a filter 108 is provided on the air vent passage 106, so that blood leakage can also be prevented.

In particular, in this embodiment, the filter 108 is not exposed to the internal region 104 of the outer needle hub 22, and is connected to the internal region 104 via a tunnel-shaped passage (communication groove 60). This can improve the effect of preventing blood leakage. That is, a filter that allows gas to pass but does not allow liquid to pass is used as the filter 108 according to the present invention, but it is not completely liquid-tight under any circumstances, and there is a limit to the liquid impermeability of the filter. Therefore, when liquid contacts the filter with excessively large pressure, the liquid (blood) can pass through the filter if the limit of the liquid impermeability of the filter is exceeded. However, in this embodiment, only blood that has flowed into the tunnel-shaped passage (communication groove 60) contacts the filter 108, so the amount of blood contacting the filter 108 and the contact pressure can be kept small, and blood leakage can be more reliably prevented.

In addition, in this embodiment, the air vent passage 106 is configured to include a through hole 58 provided in the inner locking claw 52, so that both air venting from the internal region 104 of the outer needle hub 22 and support for the elastic valve body 78 can be achieved.

Then, as shown in FIG. 7, a syringe 110 as a male connector is inserted and connected from the base end opening 102 of the outer needle hub 22 to the elastic valve body 78 of the outer needle unit 14, which is indwelled on the skin after the inner needle 18 is removed as shown in FIG. 5 and 6, and the central portion 80 of the elastic valve body 78 is pushed toward the tip side by the syringe 110 to open the slit 82. This allows the inner space of the outer needle unit 14 and the syringe 110 to communicate with each other, and transfusion, blood collection, hemodialysis, and the like are performed through the fluid flow path 112 consisting of the inner space of the outer needle unit 14 and the syringe 110. Here, since the elastic valve body 78 is provided at the base end of the outer needle hub 22, the elastic valve body 78 is pushed and opened directly by the tip of the syringe 110 when the syringe 110 is inserted, and the slit 82 of the elastic valve body 78 can be opened with the connection of the syringe 110 without providing a separate member for opening the slit 82.

In addition, in this embodiment, the outer peripheral portion of the elastic valve body 78 is supported by being sandwiched in the axial direction inside and outside by the inner locking claws 52 and the outer locking claws 68 provided on the inner housing 28 and the outer housing 30, which are hard members, so that the elastic valve body 78 can be effectively prevented from falling off from the outer needle hub 22 when the syringe 110 is connected. In particular, in this embodiment, the tip side support part 100 of the cylindrical support part 84 provided on the outer periphery of the elastic valve body 78 extends significantly toward the tip side, so that even when the syringe 110 is pushed toward the tip side relative to the elastic valve body 78, the cylindrical support part 84 can be more effectively prevented from falling off from between the inner and outer locking claws 52, 68. In addition, the air vent passage 106 extending toward the tip side is formed by skillfully utilizing such a tip side support part 100, and the tip side support part 100 can achieve both prevention of the elastic valve body 78 from falling off and formation of the air vent passage 106.

The syringe 110 connected to the outer needle unit 14 is not limited in any way, but the tip portion of the syringe 110 in this embodiment has a tapered surface in which the outer diameter gradually decreases toward the tip, and the minimum outer diameter D (see FIG. 7) at the tip portion of the syringe 110 is smaller than the inner diameter A of the outer locking claw 68. On the other hand, the maximum outer diameter E (see FIG. 7) at the tip portion of the syringe 110 is larger than the inner diameter A of the outer locking claw 68. As a result, when the syringe 110 is inserted into the outer needle unit 14, the outer locking claw 68 and the outer peripheral surface of the syringe 110 come into contact with each other and engage, so that the insertion end of the syringe 110 can be determined.

In addition, in this embodiment, when the syringe 110 is inserted and the central portion 80 of the elastic valve body 78 is deformed so as to be pushed out toward the tip side, the tip surface of the central portion 80 is overlapped with the inner peripheral surface of the internal housing 28. In particular, in this embodiment, a concave groove portion 96 is provided on the inner peripheral side of the inner locking claw 52, and when the syringe 110 is inserted, the inner peripheral surface (curved surface 54) of the inner locking claw 52 and the inner peripheral surface of the concave groove portion 96 are overlapped with each other without any gaps. As a result, the opening on the inner peripheral side of the through hole 58 in the inner locking claw 52 is covered and the air vent passage 106 is blocked, so that blood remaining in the air vent passage 106 is prevented from entering the fluid flow path 112, and air is prevented from re-entering the fluid flow path 112 through the air vent passage 106.

For example, a medical valve equipped with an elastic valve body is attached to the mixing portion of a three-way stopcock. In such a medical valve, it is preferable that air in the medical valve is discharged during priming so that air does not get mixed into the patient's body during infusion, etc. In addition, it is preferable that the elastic valve body does not fall off from the housing when a male connector is connected to the medical valve and the elastic valve body is pushed open. In order to solve such problems, FIG. 8 shows a medical valve 120 as another embodiment of the present invention. This medical valve 120 has a housing 122 to which the elastic valve body 78 is attached, and the housing 122 is composed of a base member 124, an inner housing 28, and an outer housing 30. Note that the medical valve 120 in this embodiment has a structure similar to that of the outer needle hub (22) in the indwelling needle assembly (10) of the above embodiment, but can be understood as a different invention having a different problem from the indwelling needle assembly (10) of the above embodiment. Here, in the medical valve 120 of this embodiment, the components and parts that are substantially the same as those in the previous embodiment are given the same reference numerals in the drawings, and detailed descriptions are omitted.

The base member 124 of this embodiment is configured by providing a peripheral wall portion 128 on the outer periphery of a central cylindrical portion 126 extending in the axial direction (vertical direction in FIG. 8), and connecting the upper end portions of each with an annular upper bottom portion 130. The axial dimension of this central cylindrical portion 126 is made larger than the axial dimension of the peripheral wall portion 128, and the central cylindrical portion 126 protrudes downward inside the peripheral wall portion 128. A female thread portion 132 is formed on the inner periphery of the peripheral wall portion 128, so that a lure lock type connector or the like can be connected. In addition, an insertion portion 46 that is inserted into the filter 108 protrudes from the upper bottom portion 130 toward the upper side in FIG. 8, and an annular support portion 48 further protrudes from the insertion portion 46.

The housing 122 of this embodiment is constructed by assembling the internal housing 28 and external housing 30 to the base member 124 constructed as described above in the same manner as in the previous embodiment, and the medical valve 120 of this embodiment is constructed by attaching the elastic valve body 78 and the filter 108 to the housing 122. That is, in this embodiment, one opening 134 of the substantially cylindrical housing 122 (the opening on the axially outer side of the external housing 30) is used as a port for connecting a male connector, and the elastic valve body 78 is attached to this port (opening 134).

The medical valve 120 of this embodiment having such a structure is used for infusion of drugs such as anticancer drugs and physiological saline, and is attached to the mixing portion of a three-way stopcock. Then, by flowing a priming liquid or the like from another port of the three-way stopcock through the central cylindrical portion 126 into the area inside the port of the medical valve 120 (the internal area 104), the air in the internal area 104 can be discharged through the air vent passage 106. Also in this embodiment, the outer peripheral portion of the elastic valve body 78 is supported by being sandwiched between the inner and outer locking claws 52, 68, so that the elastic valve body 78 is stably supported against the housing 122. In particular, in this embodiment, the air vent passage 106 is configured to include a through hole 58 formed through the inner locking claw (inner claw portion) 52, so that both the discharge of air and the support of the elastic valve body 78 can be achieved.

In the above embodiment, the syringe 110 is inserted into the elastic valve body 78 after the inner needle 18 is removed, but the elastic valve body 78 of this embodiment is also suitable for use when, for example, a needle with a blunt tip is inserted. Such a syringe or blunt needle is not kept inserted for a long period of time before the medical valve 120 is used, and even if a syringe or blunt needle is inserted when the medical valve 120 is used, problems such as bending of the elastic valve body 78 do not occur.

Although the embodiments of the present invention have been described above, the present invention should not be interpreted as being limited to the specific descriptions in the embodiments, and can be implemented in various forms with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art.

For example, in the above embodiment, the inner locking groove 88 and the outer locking groove 90 were formed when the elastic valve body 78 was molded, but they do not need to be formed during molding. When assembled to the outer needle hub or housing, the inner locking claw and the outer locking groove may be formed by, for example, pressing the inner and outer surfaces of the elastic valve body, which has a flat surface, into the elastic valve body to deform it. Even in such a case, it is possible to stably discharge air by, for example, configuring the through hole in the inner locking claw so that it is not blocked by the elastic valve body.

In addition, in the above embodiment, the outer protrusion 94 is compressed in the radial direction by the outer locking claw 68, but instead of or in addition to this, the inner protrusion may be compressed in the radial direction by the inner locking claw. However, the embodiment in which the outer protrusion is compressed in the radial direction by the outer locking claw is preferable to the embodiment in which the inner protrusion is compressed in the radial direction by the inner locking claw, and this more effectively prevents the elastic valve body from opening outward when pressure from backflowing blood is applied to the elastic valve body.

When the outward protrusion is compressed radially by the outer locking claw, as in the above embodiment, the inward protrusion is not essential, and in that case the tip end surface of the elastic valve body may be a flat surface as shown by the lower two-dot chain line in FIG. 4. Similarly, when the inward protrusion is compressed radially by the inner locking claw, the outward protrusion is not essential, and in that case the base end surface of the elastic valve body may be a flat surface as shown by the upper two-dot chain line in FIG. 4.

Furthermore, in the above embodiment, the outer surface (base end surface 66a) of the outer needle hub 22 and the outer surface (base end surface 80a) of the elastic valve body 78 are located on approximately the same plane, but this is not limited to this aspect. That is, the outer surface of the elastic valve body may be located axially outward or inward with a smooth surface relative to the outer surface of the outer needle hub, or may be located axially outward or inward without having a smooth surface. It is preferable that the outer surface of the outer needle hub and the outer surface of the elastic valve body are smoothly continuous, and that the difference in unevenness in the axial direction is within 2 mm, and more preferably, the difference in unevenness in the axial direction is within 1 mm. This makes it easier to perform disinfection operations such as wiping the outer surface of the elastic valve body with a disinfectant cloth.

Furthermore, in the present invention, an air vent passage that connects the internal region of the outer needle hub or the port for connecting the male connector to the outside is not essential. Even if an air vent passage is provided, a through hole that connects the internal region to the communication groove provided on the outer circumferential surface of the internal housing does not need to be provided in the inner locking claw (inner claw portion), and a through hole may be formed, for example, by penetrating the peripheral wall of the internal housing in the radial direction. However, providing such a through hole in the inner locking claw is preferable because the elastic valve body deforms when the male connector is connected, covering the opening of the through hole and closing the air vent passage. Furthermore, even if a portion that communicates between the internal region and the communication groove is provided on the inner locking claw, it is not limited to the form of a through hole 58 that penetrates radially through the axial middle portion of the inner locking claw 52 as in the above embodiment. For example, a notched groove that extends continuously in the axial direction from the inner peripheral surface to the outer peripheral surface at the protruding tip of the inner locking claw may be provided on the outer surface, and the internal region and the communication groove may be communicated by the groove.

Furthermore, the filter only needs to be provided on the air vent passage, and is not limited to being inserted into the inner insertion portion 46 of the base member 26, 124 as in the above embodiment. The filter is not limited to being not exposed to the internal region of the outer needle hub or the port for connecting the male connector, and may be exposed to the internal region, for example, by being disposed in a through hole provided in the inner locking claw (inner claw portion). In addition, the filter is not limited to being provided inside the outer needle hub of the indwelling needle assembly or the housing of the medical valve, and may be exposed to the outer peripheral surface of the outer needle hub or the housing, for example. However, the filter being provided inside the outer needle hub or the housing is preferable because it is more difficult to contact from the outside and blood leakage is more effectively prevented.

Furthermore, in the above embodiment, the communication groove 60 constituting the air vent passage 106 was provided on the outer peripheral surface of the inner housing 28, but instead of or in addition to the outer peripheral surface of the inner housing, it may be provided on the inner peripheral surface of the tip support part of the elastic valve body. In the above embodiment, a pair of communication grooves 60, 60 is provided on the outer peripheral surface of the inner housing 28, and each of these forms a pair of air vent passages 106, 106 in the outer needle hub 22 and the housing 122, but the number of these communication grooves and air vent passages is not limited in any way. Furthermore, for example, when an air vent passage extending linearly in the axial direction is used as in the above embodiment, it is preferable that at least one of the air vent passages is formed so as to be located upward in the direction of gravity during puncture.

In addition, in the above embodiment, the inner diameter dimension A of the outer locking claw 68 is smaller than the inner diameter dimension B of the inner locking claw 52, but it may be larger.

In addition, in the above embodiment, the outer needle hub 22 of the indwelling needle assembly 10 and the housing 122 of the medical valve 120 are composed of three parts, but they may be composed of two parts, for example, with the base member and the inner housing being integrated. In addition, the multiple parts that make up the outer needle hub 22 and the housing 122 may be fixed, for example, by ultrasonic welding, but by fixing them by recess-projection fitting or the like, it is possible to prevent the diameter from becoming large compared to the case of ultrasonic welding, and to avoid the use of special parts or devices.

Furthermore, the recessed groove on the base end surface of the elastic valve body is not essential. Also, the inclined surface (tapered surface) on the inner peripheral surface of the outer locking claw is not essential. Furthermore, the inner peripheral surface of the inner locking claw does not need to be a curved surface. The shape of the elastic valve body is not limited in any way, and for example, the tip end surface of the tip support part of the elastic valve body may be at approximately the same axial position as the tip end surface of the central part. In such a case, the air vent passage is configured to include, for example, a communication passage provided between the outer housing and the inner housing.

In addition, in the first embodiment, the outer needle hub 22 directly supports the outer needle 20, but for example, a member that directly supports the outer needle may be provided separately, and the member that supports the outer needle and the base member may be connected, for example, by an elastic tube, or the outer needle hub may indirectly support the outer needle.

The aspects described below can be recognized as independent inventions that can solve problems different from those of the present invention.

In other words, there was a need for a needle assembly that is inserted into a patient's blood vessel and left in place, and that achieves both air release from inside the needle hub and stable support of the elastic valve body.

The first aspect of the present invention, which has been made to solve such problems, is characterized in that in a needle assembly in which an elastic valve body is attached inside a needle hub equipped with a hollow needle, an inner locking claw provided on the needle hub is locked to the outer periphery of the elastic valve body, an air vent passage is formed through a radial through hole provided in the part of the needle hub where the inner locking claw is formed, which connects the internal region of the needle hub further to the tip side than the elastic valve body with the outside, and a filter that allows the passage of gas but prevents the passage of liquid is arranged in communication with the internal region of the needle hub through the air vent passage.

10: Indwelling needle assembly, 18: Inner needle, 22: Outer needle hub, 26: Base member, 28: Inner housing, 30: Outer housing, 52: Inner locking claw (inner claw portion), 58: Through hole, 66a: Base end surface (outer surface of outer needle hub), 68: Outer locking claw (outer claw portion), 78: Elastic valve body, 80a: Base end surface (outer surface of elastic valve body), 82: Slit, 88: Inner locking groove, 90: Outer locking groove, 100: Tip side support part, 104: Internal region, 105: Opening, 106: Air vent passage, 108: Filter, 120: Medical valve, 122: Housing, 134: Opening (port for connecting male connector)

Claims (10)

In an indwelling needle assembly in which an inner needle is inserted into an elastic valve body which is attached to an outer needle hub and is made of a disk-shaped elastic body as a whole and has a slit formed therethrough from front to back ,
An indwelling needle assembly characterized in that an inner locking claw and an outer locking claw provided at the base end of the outer needle hub are engaged with an inner locking groove and an outer locking groove formed on the outer periphery of the elastic valve body, and the elastic valve body is compressed in the radial direction by at least one of the inner locking claw and the outer locking claw. The indwelling needle assembly according to claim 1, wherein the elastic valve body is compressed in the radial direction by the outer locking claw. The indwelling needle assembly according to claim 1 or 2, wherein the outer surface of the outer needle hub and the outer surface of the elastic valve body are connected by a smooth surface. The indwelling needle assembly according to any one of claims 1 to 3, in which an air vent passage is formed that connects the internal region of the outer needle hub that is on the tip side of the elastic valve body to the outside, and a filter that allows the passage of gas but prevents the passage of liquid is disposed at a position away from the opening of the air vent passage to the internal region. The indwelling needle assembly according to claim 4, wherein the air vent passage extends toward the tip side. The indwelling needle assembly according to claim 5, wherein the elastic valve body has a tip support part that extends toward the tip side on the outer circumferential side of the inner locking groove and the outer locking groove, and the air vent passage that extends toward the tip side is formed between the inner surface of the tip support part and the outer needle hub. The indwelling needle assembly according to any one of claims 4 to 6, wherein a radial through hole is formed in the portion of the outer needle hub where the inner locking claw is formed, and the air vent passage is configured to include the through hole. The indwelling needle assembly according to any one of claims 4 to 7, wherein the filter is disposed inside the outer needle hub. The indwelling needle assembly according to any one of claims 1 to 8, wherein the outer needle hub is configured to include an outer housing having the outer locking claw and an inner housing having the inner locking claw, and multiple members including the outer housing and the inner housing are fixed by a concave-convex fit. A medical valve in which a disk-shaped elastic valve body is attached and a port for connecting a male connector is provided, and in which an inner hook portion and an outer hook portion formed on a housing are engaged and supported by an inner locking groove and an outer locking groove formed on an outer periphery of the elastic valve body,
a medical valve characterized in that an air vent passage connecting an internal region of the male connector connection port into which fluid can flow , to the outside, is formed including a radial through hole provided in a portion of the housing where the inner claw portion is formed, and a filter that allows the passage of gas but prevents the passage of liquid is disposed on the air vent passage and communicates with the internal region via the air vent passage.

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