Needle tip protector and needle assembly using the same

Abstract

To provide a novel needle tip protector which can be stably produced by resin molding, such as injection molding, and a novel needle assembly using the same.SOLUTION: There is provided a resin needle tip protector A-10 which has a peripheral wall for covering a needle tip A-20 of a paracentesis needle A-16 by moving in a needle axis direction with respect to the paracentesis needle A-16, where a peripheral wall A-54 has a cylindrical part on a tip end. The peripheral wall A-54 has a thick part A-70 including a part whose thickness dimension is greater than that of a cylindrical part A-58, the thick part being provided on a base end side of the cylindrical part A-58, and an injection gate trace A-98 of the resin material in molding is provided on the thick part A-70.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention (Invention A) relates to a needle tip protector that covers the tip of a removed puncture needle, and a needle assembly that includes the needle tip protector. [Background technology]

[0002] Needle tip protectors have been used to protect the tip of puncture needles removed from a body lumen, for purposes such as preventing accidental punctures or repeated use of puncture needles, such as indwelling needles used in transfusions, blood collection, hemodialysis, etc., or facilitating disposal. A needle tip protector and a needle assembly including the same are disclosed, for example, in Japanese Patent Laid-Open Publication No. 2017-196060 (Patent Document 1). That is, with the medical needle with a protector disclosed in Patent Document 1, when the needle tube is pulled out of a blood vessel or the like, the protector moves toward the needle tip relative to the needle tube, and the needle tube removed from the patient is housed within the protector, preventing the needle tip of the needle tube from being exposed to the outside.

[0003] Incidentally, needle tip protectors may be made of resin, and in this case, they are manufactured by molding, such as injection molding, etc. That is, a needle tip protector of a predetermined shape is manufactured by filling a resin material into a cavity of a mold corresponding to the shape of the needle tip protector and hardening it. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-196060 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the needle tip protector has a relatively thin peripheral wall that surrounds and covers the puncture needle, and when attempting to form the needle tip protector by molding, problems such as incomplete filling of the resin material due to pressure loss can occur. Also, from the perspective of how medical professionals use the protector and the patients who use it, there is room for improvement.

[0006] The problem to be solved by Invention A is to provide a novel needle tip protector that is highly safe and can be stably manufactured by resin molding such as injection molding.

[0007] Another object of the invention A is to provide a needle assembly including the above-mentioned needle tip protector as a needle tip protector that protects the tip of the puncture needle that constitutes the puncture needle body. [Means for solving the problem]

[0008] Below, we will describe preferred embodiments for understanding Invention A. However, each embodiment described below is an example and can be appropriately combined with each other. Multiple components described in each embodiment can be recognized and used independently as much as possible, and can also be appropriately combined with any component described in another embodiment. As a result, Invention A is not limited to the embodiments described below, and various other embodiments can be realized.

[0009] A first aspect of the present invention is a needle tip protector made of resin and having a peripheral wall that moves in the needle axial direction relative to the puncture needle to cover the tip of the puncture needle, the peripheral wall having a cylindrical portion on the distal end side, and the peripheral wall having a thick portion on the proximal end side of the cylindrical portion that has a portion with a thickness dimension greater than that of the cylindrical portion, and a trace of an injection gate of resin material during molding is formed in the thick portion. On the outer surface ofThe outer dimensions of at least the base end of the peripheral wall in the axis-perpendicular direction are different in the circumferential direction, and the wide portion with the larger outer dimensions is provided with an engaging portion that engages with a needle hub fixed to the base end of the puncture needle, and a locking piece that is locked to the needle hub and prevents the needle tip from re-extruding, and the injection gate mark is provided in the narrow portion with the smaller outer dimensions, so that the injection gate mark is located at a position circumferentially separated from the engaging portion and the locking piece. On the other hand, the inner peripheral surface corresponding to the injection gate mark has a recessed portion toward the injection gate mark. It is something. A second aspect of the present invention is a needle tip protector made of resin and having a peripheral wall that covers the tip of a puncture needle by moving in the needle axial direction relative to the puncture needle, the peripheral wall having a cylindrical portion on the distal end side, and a portion on the proximal end side of the cylindrical portion that is thicker than the cylindrical portion. The enlarged portion is provided with an outer dimension enlarged to include the The outer surface of the peripheral wall is formed by an axial punching die and has a parting line extending in the axial direction. The cylindrical portion and the expanded portion have a parting line extending in the circumferential direction along the boundary therebetween, and the expanded portion is located away from the parting line toward the axial base end, and a trace of a resin material injection gate used during molding is provided on the axial base end side of the expanded portion. It is something. The first aspect of invention A of the parent application is a needle tip protector made of resin and having a peripheral wall that covers the tip of a puncture needle by moving in the needle axial direction relative to the puncture needle, the peripheral wall having a cylindrical portion at the tip end, the peripheral wall having a thick portion at the base end of the cylindrical portion that has a portion with a thickness dimension greater than that of the cylindrical portion, a trace of an injection gate for resin material during molding is provided in the thick portion, a recess is provided on the outer surface of the thick portion, and the injection gate trace is provided on the inner surface of the recess.

[0010] In the case of the needle tip protector of this embodiment, when molding, an injection gate for the resin material is set in the portion where the thick portion of the peripheral wall is molded, and the resin material is filled in the cavity of the mold from the portion with the larger cross-sectional area to the portion with the smaller cross-sectional area. Therefore, when filling the cavity with the resin material, pressure loss due to changes in the cross-sectional area of ​​the cavity is unlikely to occur, and it is possible to avoid improper filling of the resin material, and it is possible to stably obtain a needle tip protector of the desired shape. Furthermore, it is possible to prevent the thick-walled portion from becoming excessively thick. As a result, it is possible to avoid problems such as the inclusion of air bubbles in the thick-walled portion, the occurrence of sink marks or voids, etc. For example, if the thickness of the thick-walled portion is not constant because the inner and outer surfaces of the thick-walled portion have different shapes, a recess can be provided on the outer surface of the thick-walled portion where the thickness is particularly thick. As a result, it is possible to prevent the thick-walled portion from becoming significantly thick in parts.

[0014] moreover,For example, if the injection gate mark is to have a protruding shape, providing the injection gate mark on the inner surface of the recess makes it less likely to protrude outward from the outer surface of the thick portion. This makes it less likely that the injection gate mark will catch on the patient's skin and cause pain when the thick portion comes into contact with the patient's skin.

[0015] Although the thickness of the peripheral wall decreases where the recess is formed, forming the recess in a thick section including a thicker section can prevent the peripheral wall from becoming excessively thin where the recess is formed. Therefore, even when forming an injection gate mark on the inner surface of the recess to prevent the injection gate mark from coming into contact with the patient, etc., it is possible to effectively prevent insufficient filling of the resin material during molding and stably manufacture needle tip protectors of the desired shape.

[0016] Pertaining to the parent application Invention A 2 The embodiment of Pertaining to the parent application Invention A 1 In the needle tip protector according to the aspect (2), the depth dimension of the recess gradually decreases toward the tip side of the peripheral wall.

[0017] According to the needle tip protector of this embodiment, for example, when the position of the injection gate is set so that an injection gate mark is left on the inner surface of the recess, it is possible to avoid a sudden change in the filling pressure of the resin material during molding and therefore in the resin density during molding, thereby ensuring the strength of the needle tip protector and preventing molding defects such as sink marks.

[0018] Pertaining to the parent application Invention A 3 The embodiment of Pertaining to the parent application Invention A 1 or 2 In the needle tip protector according to the embodiment of the present invention, the opening edge of the recess has a curved cross-sectional shape without any corners.

[0019] The needle tip protector of this aspect is less likely to cause pain or discomfort to the patient when the opening edge of the recess comes into contact with the patient's skin. In addition, the opening edge of the recess is formed without corners, making it less likely to chip or cause other problems. The fourth aspect of invention A of the parent application is a needle tip protector described in any one of the first to third aspects of invention A of the parent application, in which the bottom wall of the recess is thicker than the tubular portion. The fifth aspect of invention A of the parent application is a needle tip protector made of resin and equipped with a peripheral wall that moves in the needle axial direction relative to the puncture needle to cover the tip of the puncture needle, the peripheral wall having a cylindrical portion on the distal end side, and a thick portion having a portion thicker than the cylindrical portion on the proximal end side of the cylindrical portion, and a trace of an injection gate of resin material used during molding is provided in the thick portion, the peripheral wall is transparent or translucent to allow light to pass through, and the translucency of the peripheral wall at the injection gate trace is lower than that of other parts of the peripheral wall. . In the present embodiment, when molding the needle tip protector, a resin material injection gate is set in the portion of the peripheral wall where the thick portion is molded, and the resin material is filled in the mold cavity from the portion with the larger cross-sectional area to the portion with the smaller cross-sectional area. Therefore, when filling the cavity with the resin material, pressure loss due to changes in the cross-sectional area of ​​the cavity is unlikely to occur, and poor filling of the resin material can be avoided, making it possible to reliably obtain a needle tip protector of a predetermined shape. Furthermore, because the injection gate mark can be easily confirmed visually due to differences in translucency, the injection gate mark can be used as a marker to easily determine the orientation of the needle tip protector.

[0020] A sixth aspect of Invention A is a needle tip protector described in any one of the first to fifth aspects of Invention A, wherein the peripheral wall has an expansion portion at the base end side of the tubular portion that includes a portion that is thicker than the tubular portion and has larger outer dimensions, and the injection gate mark is provided on the outer surface of the expansion portion.

[0021] According to the needle tip protector of this embodiment, a thick-walled portion where an injection gate mark is set is provided in the expanded portion where the outer diameter is increased, making it possible to prevent the inner diameter of the peripheral wall including the expanded portion from becoming significantly smaller in the thick-walled portion.

[0024] Pertaining to the parent application Invention A 7 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 6 In the needle tip protector described in any one of the above aspects, the injection gate mark is provided at a position away from the engagement portion that engages with the needle hub provided on the base end side of the puncture needle.

[0025] According to the needle tip protector of this embodiment, the injection gate is set at a position away from the part where the shape becomes complex or the cross-sectional area becomes small due to the formation of the engagement part, thereby more effectively avoiding molding defects.

[0026] Pertaining to the parent application Invention A 8 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 7 In the needle tip protector described in any one of the above aspects, a locking piece is provided that is engaged with a needle hub provided on the base end side of the puncture needle when the peripheral wall covers the needle tip of the puncture needle, thereby preventing the needle tip from being re-exposed, and the injection gate mark is provided at a position where it is disengaged from the locking piece.

[0027] According to the needle tip protector of this aspect, by making the portion of the peripheral wall away from the locking piece a thick portion, the portion of the peripheral wall where the locking piece is provided can be made relatively thin. As a result, it is possible to prevent air bubbles from being mixed into the locking piece and to prevent the occurrence of sink marks or voids. Furthermore, by setting the injection gate at a position away from the portion where the shape becomes complex or the cross-sectional area becomes small due to the formation of the locking piece, it is possible to more effectively avoid molding defects.

[0028] Pertaining to the parent application Invention A 9 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 8 In the needle tip protector according to any one of the above aspects, the outer surface of the peripheral wall is formed by a split mold in the axis-perpendicular direction and has a parting line extending in the axial direction.

[0029] According to the needle tip protector of this aspect, it is possible to realize a great degree of freedom in the shape of the outer surface of the peripheral wall. If the injection gate position of the resin material is set so that an injection gate mark is formed on the outer surface of the peripheral wall, it is possible to employ a pin gate in which the runner is pulled and cut when the split mold is removed in the direction perpendicular to the axis, which makes it easier to mold multiple needle tip protectors simultaneously in a small space and improves the mass productivity of needle tip protectors.

[0030] Pertaining to the parent application Invention A 10 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 8 In the needle tip protector according to any one of the above aspects, the outer surface of the peripheral wall is formed by an axial punching die and does not have a parting line extending in the axial direction.

[0031] In the needle tip protector of this embodiment, if the injection gate position of the resin material is set so that an injection gate mark is formed on the outer surface of the peripheral wall, a tunnel gate can be adopted in which the runner is cut by the die when the die is removed in the axial direction. Therefore, the needle tip protector can be manufactured using a relatively small amount of molding material.

[0032] Pertaining to the parent application Invention A 11 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 10 In the needle tip protector according to any one of the above aspects, a plurality of the injection gate marks are provided in the circumferential direction of the peripheral wall.

[0033] According to the needle tip protector of this aspect, by filling the cavity of the mold with resin material from multiple locations in the circumferential direction during molding, it becomes more unlikely that improper filling of the resin material will occur.

[0034] Pertaining to the parent application Invention A 12 The embodiment of Pertaining to the parent application Invention A 1st to 2nd 11 In the needle tip protector described in any one of the above aspects, the outer dimensions of at least the base end of the peripheral wall in the direction perpendicular to the axis are different in the circumferential direction, and at least one of an engagement portion that engages with a needle hub fixed to the base end of the puncture needle and an engagement piece that engages with the needle hub to prevent the needle tip from re-protruding is provided in the wide portion where the outer dimensions are larger, and the injection gate mark is provided in the narrow portion where the outer dimensions are smaller.

[0035] According to the needle tip protector of this aspect, the wide portion, which has a large outer dimension in the axis-perpendicular direction, can easily secure a space for arranging at least one of the engaging portion and the locking portion. The narrow portion, which has a small outer dimension in the axis-perpendicular direction, can easily be made thicker than the wide portion in which the engaging portion and / or the locking portion are arranged, allowing for efficient filling of the resin material during molding.

[0038] Pertaining to the parent application Invention A 13 The above aspect is a needle assembly including a needle tip protector that moves in the needle axis direction relative to a puncture needle body that includes a puncture needle to cover the needle tip of the puncture needle, and the needle tip protector The needle tip protector is made of resin and has a peripheral wall that moves in the needle axial direction relative to the puncture needle to cover the tip of the puncture needle, the peripheral wall having a cylindrical portion on the distal end side, and the peripheral wall having a thick portion on the proximal end side of the cylindrical portion that has a portion with a thickness dimension greater than that of the cylindrical portion, and a trace of an injection gate of resin material during molding is provided in the thick portion, and a recess is provided on the outer surface of the thick portion. It is a needle tip protector, and the needle tip protector Applicable At least a part of the outer surface of the thickened portion is a contact portion that comes into contact with the patient's skin, and the contact portion Applicable The recess is open.

[0039] According to the needle assembly of this aspect, by providing a recess in the contact portion of the needle tip protector, the area of ​​the contact portion that comes into contact with the patient's body surface is reduced, thereby reducing pain and discomfort caused by contact with the contact portion.

[0040] Pertaining to the parent application Invention A 14 The embodiment of Pertaining to the parent application Invention A 13 In the needle assembly according to the aspect 1, the contact portion comes into contact with the patient's skin when the puncture needle body is placed.

[0041] According to the needle assembly of this aspect, a recess is provided in the contact portion that comes into contact with the patient when the indwelling needle serving as the puncture needle body is placed, and the contact area of ​​the contact portion with the patient is reduced, thereby reducing the pain and discomfort felt by the patient due to contact with the contact portion during placement.

[0042] Pertaining to the parent application Invention A 15 The embodiment of Pertaining to the parent application Invention A 13 or 14 In the needle assembly according to the aspect 1, the injection gate mark is provided at a position away from the contact portion.

[0043] According to the needle assembly of this aspect, the injection gate mark is prevented from coming into contact with the patient, so that even if the needle tip protector comes into contact with the patient, the patient is less likely to experience pain or discomfort.

[0044] Pertaining to the parent application Invention A 16 The embodiment of Pertaining to the parent application Invention A 13 ~No. 15 In the needle assembly described in any one of the above aspects, a protruding pin mark is provided on the outer surface of the thick portion of the needle tip protector at either the contact portion or a portion located radially opposite the contact portion.

[0045] According to the needle assembly of this aspect, the pin mark formed by the pin of the mold used to remove the molded product from the mold is set at either the contact part on the outer surface of the thick part of the needle tip protector or the radially opposite side of the contact part, so that the orientation of the contact part on the needle tip protector can be grasped using the pin mark as a marker.

[0046] Pertaining to the parent application Invention A 17 The above aspect is a needle assembly including a needle tip protector that covers the tip of the puncture needle by moving in the needle axis direction relative to a puncture needle body that includes a puncture needle, and the needle tip protector Invention A in the parent application No. of 6 The needle tip protector is a needle tip protector described in the above aspect, in which the expansion portion has a narrow portion and a wide portion having an outer dimension larger than that of the narrow portion, the injection gate trace is provided on the wide portion side, and the needle tip protector has an engaging portion on the wide portion that can be detachably engaged with an engaging arm provided on a needle hub fixed to the base end of the puncture needle.

[0047] According to the needle assembly of this aspect, the injection gate (injection gate mark) is provided in the wide portion, which makes it difficult for a weld line to form at the engagement portion. As a result, the strength of the engagement portion of the needle tip protector is increased, allowing the engagement arm of the needle hub to be more firmly engaged with the needle tip protector. This prevents unintended separation of the needle hub and the needle tip protector, preventing malfunction of the needle tip protection mechanism. Furthermore, it also prevents problems such as the engagement portion being destroyed by external force, causing the needle tip protection mechanism to malfunction.

[0048] Invention A in the parent application No. 17 In this embodiment, the injection gate mark is preferably provided on the proximal side of the engagement portion. The engagement portion is often provided at the proximal end of the needle tip protector, and since the strength of the proximal end of the needle tip protector is easily reduced, greater strength is required. Therefore, by configuring it in this way, it is possible to make it less likely for a weld line to occur on the proximal side of the engagement portion. As a result, the strength of the engagement portion is increased, further improving safety. [Effects of the Invention]

[0049] According to Invention A, the needle tip protector is highly safe and can be stably formed by molding resin using injection molding or the like. [Brief explanation of the drawings]

[0050] [Figure 1] FIG. 1 is a plan view showing a needle assembly according to a first embodiment of the present invention; [Figure 2] 2 is a bottom view of the needle assembly shown in FIG. [Figure 3] FIG. 2 is a front view of the needle assembly shown in FIG. [Figure 4] IV-IV cross section of Figure 3 [Figure 5] VV cross section of Figure 1 [Figure 6] FIG. 2 is a perspective view of a needle tip protector that constitutes the needle assembly shown in FIG. 1; [Figure 7] Right side view of the needle tip protector shown in Figure 6 [Figure 8] 7A and 7B are longitudinal cross-sectional views illustrating the manufacturing process of the needle tip protector shown in FIG. [Figure 9] FIG. 2 is a longitudinal cross-sectional view showing the needle tip protected by the needle tip protector in the needle assembly shown in FIG. 1; [Figure 10] FIG. 1 is a longitudinal cross-sectional view showing a main part of a needle assembly according to a second embodiment of the present invention. [Figure 11] 10 is a longitudinal sectional view illustrating a manufacturing process of a needle tip protector according to another embodiment of the present invention. [Figure 12] A perspective view of a needle tip protector as another embodiment of the invention A. [Figure 13] A perspective view of a needle tip protector as another embodiment of the invention A. [Figure 14] A perspective view of a needle tip protector as another embodiment of the invention A. [Figure 15] FIG. 1 is a plan view of a needle assembly having a puncture needle body as a first embodiment of invention B. [Figure 16] FIG. 16 is a front view of the needle assembly shown in FIG. [Figure 17] Section XVII-XVII of Figure 16 [Figure 18] XVIII-XVIII cross section of Figure 15 [Figure 19] FIG. 16 is a longitudinal cross-sectional view showing the needle tip protected by the needle tip protector in the needle assembly shown in FIG. 15. [Figure 20] FIG. 1 is a longitudinal cross-sectional view of a puncture needle body as a second embodiment of invention B. [Figure 21] FIG. 1 is a plan view showing a needle assembly according to a first embodiment of the present invention; [Figure 22] FIG. 22 is a front view of the needle assembly shown in FIG. [Figure 23] XXIII-XXIII cross section of Figure 22 [Figure 24] FIG. 24 is an enlarged view of a main part of FIG. 23; [Figure 25] XXV-XXV cross section of Figure 21 [Figure 26] 22 is a perspective view of a needle tip protector that constitutes the needle assembly shown in FIG. 21. [Figure 27] Right side view of the needle tip protector shown in Figure 26 [Figure 28] 26 is a cross-sectional view showing the needle assembly shown in FIG. 25 in a state where the needle hub is being pulled out toward the base end side relative to the needle tip protector, and shows a state where tilting of the indwelling needle is restricted by the abutment portion. [Figure 29] 26 is a cross-sectional view showing the needle assembly shown in FIG. 25 in a state where the needle hub has been pulled out toward the base end until the needle tip of the puncture needle is aligned with the tip of the needle tip protector, and shows a state where tilting of the indwelling needle is restricted by the abutment portion. [Figure 30] 34 is a cross-sectional view showing the needle assembly shown in FIG. 21 in a state where the needle tip is protected; [Figure 31] 31 is an enlarged cross-sectional view showing a main part of FIG. 30. [Figure 32] 31 is a cross-sectional view showing the main part of a needle assembly provided with a needle tip protector as another embodiment of invention C in a state where the needle tip is protected. [Figure 33] FIG. 1 is a plan view showing a needle assembly with a needle tip protector as a first embodiment of invention D. [Figure 34] FIG. 34 is a front view of the needle assembly with the needle tip protector shown in FIG. 33. [Figure 35] XXXV-XXXV cross section of Figure 33 [Figure 36] XXXVI-XXXVI cross section of Figure 35 [Figure 37] 34 is a perspective view of a second part of the needle hub that constitutes the needle assembly with needle tip protector shown in FIG. 33; DETAILED DESCRIPTION OF THE INVENTION

[0051] Hereinafter, an embodiment of the invention A will be described with reference to the drawings.

[0052] 1 to 5 show a needle assembly A-12 equipped with a needle tip protector A-10 as a first embodiment of invention A. The needle assembly A-12 has a structure in which a puncture needle A-14 is inserted into the needle tip protector A-10 so as to be movable in the needle axial direction. In the following description, unless otherwise specified, the distal end refers to the left side in FIG. 1, which is the side of the needle tip A-20 (described later) of the puncture needle A-14, and the proximal end refers to the right side in FIG. 1, which is the rear side in the puncture direction of the puncture needle A-14. Furthermore, as a general rule, the up-down direction refers to the vertical direction in FIG. 3, which is the vertical direction, and the left-right direction refers to the horizontal direction in FIG. 1. For ease of viewing, in FIGS. 1 to 14 relating to invention A, the "A-" has been omitted from each reference numeral "A-XX" (XX is a number corresponding to a part). In addition, in order to make it easier to understand that FIGS. 1 to 14 are drawings relating to Invention A, [Invention A] is written in FIGS.

[0053] More specifically, the puncture needle body A-14 comprises a puncture needle A-16 and a needle hub A-18. The puncture needle A-16 is made of a metal such as stainless steel, and has a sharp, tapered tip A-20 at one end. A through-hole A-22 is formed at the tip of the puncture needle A-16, allowing blood to easily flow into the lumen of the puncture needle A-16.

[0054] The needle hub A-18 has a generally cylindrical shape overall, and the base end portion of the puncture needle A-16 is inserted and fixed in its tip portion. This allows the inner cavity of the needle hub A-18 to communicate with the inner cavity of the puncture needle A-16 in the needle axial direction. The needle hub A-18 has a needle support portion A-24 that forms the tip portion and a protector connecting portion A-26 that forms the base portion.

[0055] The needle support part A-24 has a substantially cylindrical shape and is made of, for example, a hard resin. The inner diameter of the tip of the needle support part A-24 is substantially the same as the outer diameter of the puncture needle A-16. An annular positioning protrusion A-28 protruding inward is provided on the inner peripheral surface of the tip of the needle support part A-24. The base end of the puncture needle A-16 is inserted through the opening at the tip side of the needle support part A-24, and the base end of the puncture needle A-16 and the positioning protrusion A-28 come into contact with each other, thereby positioning the puncture needle A-16 in the needle axial direction (left-right direction in FIG. 1) relative to the needle hub A-18. The puncture needle A-16 and the needle support part A-24 may be bonded together, if necessary.

[0056] The needle support part A-24 has a tapered surface A-30 on the outer circumferential surface of the intermediate part in the needle axis direction, the diameter of which gradually increases toward the tip side. As a result, the intermediate part in the needle axis direction of the needle support part A-24 having the tapered surface A-30 is a small-diameter cylindrical part A-32 whose diameter is smaller than that of the tip and base end parts.

[0057] A locking recess A-34 that opens onto the outer circumferential surface is formed in the needle support portion A-24 at the tip end of the tapered surface A-30. The locking recess A-34 is annular and has a substantially constant cross-sectional shape all around. The minimum outer diameter of the needle support portion A-24 at the location where the locking recess A-34 is formed is substantially the same as the minimum outer diameter of the base end of the small-diameter cylindrical portion A-32.

[0058] An annular large-diameter fulcrum portion A-36 protrudes from the outer peripheral surface of the needle support portion A-24, closer to the tip than the locking recess A-34. The large-diameter fulcrum portion A-36 is provided at or near the tip of the needle support portion A-24, and in this embodiment, constitutes the tip of the needle support portion A-24. The outer diameter of the needle support portion A-24 at the portion where the large-diameter fulcrum portion A-36 is formed is larger than the outer diameter of the tip, which is the maximum outer diameter of the small-diameter cylindrical portion A-32.

[0059] The base-end side surface constituting the inner surface of the locking recess A-34 is an annular base-end restriction surface A-38 that extends in the axis-perpendicular direction, and the bottom surface of the locking recess A-34 and the tapered surface A-30 are connected in a stepped manner via the base-end restriction surface A-38. The tip-end side surface constituting the inner surface of the locking recess A-34 is an annular tip-end restriction surface A-40 that extends in the axis-perpendicular direction, and the bottom surface of the locking recess A-34 and the outer peripheral surface of the large-diameter fulcrum portion A-36 are connected in a stepped manner via the tip-end restriction surface A-40. The axis-perpendicular dimension of the base-end restriction surface A-38 formed by the base-end inner surface of the locking recess A-34 is slightly larger than the axis-perpendicular dimension of the tip-end restriction surface A-40.

[0060] The protector connecting portion A-26 is formed of a hard resin, for example, similar to the needle support portion A-24. The protector connecting portion A-26 has a stepped, generally cylindrical shape, with a small-diameter connecting tube portion A-42 at its distal end and a large-diameter connecting tube portion A-44 at its proximal end. The protector connecting portion A-26 is fixed to the needle support portion A-24 by inserting the proximal end of the needle support portion A-24 into the connecting tube portion A-42 and, if necessary, by gluing or welding. A generally rectangular recess A-46 is formed on the longitudinal surface (the up-down direction in FIG. 3 ) of the protector connecting portion A-26. In this embodiment, the recess A-46 is provided on the surface of the connecting tube portion A-42 as shown in FIG. 1, but it may also be provided on the surface of the connecting tube portion A-44 or may be provided across the connecting tube portion A-42 and the connecting tube portion A-44.

[0061] The protector connecting part A-26 is fixed to the external conduit A-47 by inserting the tip of the external conduit A-47 into the connecting tube part A-44 and applying adhesive or welding as necessary. By connecting the base end part (needle support part A-24) of the needle hub A-18 and the external conduit A-47 to both sides of the protector connecting part A-26, the inner cavity of the puncture needle A-16 and the inner cavity of the needle hub A-18 are communicated with the external conduit A-47, and a fluid flow path A-48 extending from the tip opening of the puncture needle A-16 to the external conduit A-47 is provided in the puncture needle body A-14.

[0062] The connecting tubular portion A-44 is provided with a pair of engaging arms A-50, 50 that extend toward the tip. The engaging arms A-50, 50 are arranged opposite each other in the radial direction and extend around the outer periphery of the connecting tubular portion A-42 further toward the tip than the connecting tubular portion A-42. The engaging arms A-50, 50 are arranged spaced apart from the outer periphery of the connecting tubular portion A-42, and the connecting portion with the connecting tubular portion A-44 is thin-walled and narrow, allowing elastic deformation in the direction of approaching each other when subjected to external force.

[0063] A hook A-52 is formed at the tip of each of the engaging arms A-50, 50. The hook A-52 protrudes outward in the opposing direction of the engaging arms A-50, 50 on each engaging arm A-50. The pair of hooks A-52, 52 move in directions approaching each other as the engaging arms A-50, 50 elastically deform in the approaching direction.

[0064] As shown in Figure 6, the needle tip protector A-10 has a generally cylindrical shape extending in the needle axis direction and is integrally molded from a hard synthetic resin such as polypropylene, polycarbonate, glycol-modified polyethylene terephthalate, or ABS resin. The needle tip protector A-10 is preferably transparent or translucent, allowing visible light to pass through. The needle tip protector A-10 has a cylindrical peripheral wall A-54, the inner periphery of which is formed with an inner hole A-56 penetrating in the needle axis direction. The needle tip protector A-10 does not have any bubbles, sink marks, voids, etc. within the peripheral wall A-54. The needle tip protector A-10 has a proximal opening A-57 that opens at the proximal end in the needle axis direction.

[0065] The peripheral wall A-54 has a cylindrical portion A-58 as a tubular portion having a substantially circular cross section at its tip end, and an expanding portion A-60 at its base end that has larger outer dimensions than the cylindrical portion A-58 and expands to the outer periphery, and the shapes are different in the needle axial direction. Since the expanding portion A-60 has larger outer dimensions than the cylindrical portion A-58, its circumferential length is longer than that of the cylindrical portion A-58.

[0066] As shown in FIG. 7, the expansion section A-60 has a substantially elliptical cylindrical shape, and the width dimension (external dimension) of the outer peripheral surface in the left-right direction (horizontal direction) in FIG. 7, which is the larger diameter direction, is larger than the width dimension (external dimension) of the outer peripheral surface in the up-down direction (vertical direction) in FIG. 7, which is the smaller diameter direction. Of the wall portions constituting the expansion section A-60, the portions constituting the vertical wall portion are narrow width portions A-62, 62 with small external dimensions, while the portions constituting the horizontal wall portion are wide width portions A-64, 64 with large external dimensions. The opposing direction of the narrow width portions A-62, 62 and the opposing direction of the wide width portions A-64, 64 are substantially perpendicular to each other. Note that in this embodiment, an embodiment in which the expansion section A-60 has different dimensions in the vertical direction and the horizontal direction will be described, but this is not limited to this embodiment. For example, the vertical and horizontal dimensions of the expansion section may be substantially the same. Furthermore, the cross-sectional shapes of the expanded portions A-60 on the distal and proximal sides of the needle tip protector may each be various shapes such as circular (including elliptical, oval, etc.) or polygonal. However, the expanded portion provided on the proximal side of the needle tip protector is not essential, and the needle tip protector may simply be a straight cylindrical shape.

[0067] As shown in Figures 4 to 6, the outer diameter of the outer peripheral surface of the widened portions A-64, 64 gradually increases from the distal end toward the proximal end. The outer peripheral surface of the cylindrical portion A-58 and the outer peripheral surface of the widened portions A-64, 64 are smoothly connected. The wall thickness from the cylindrical portion A-58 to the widened portions A-64, 64 is approximately constant in the needle axial direction. The widened portions A-64, 64 have a substantially elliptical cross section in which the outer peripheral surface and the inner peripheral surface correspond to each other, and the thickness is approximately constant in the circumferential direction. An internal space A-66 having a flat cross section with a larger horizontal dimension than a vertical dimension is formed on the inner periphery of the expanded portion A-60 at the proximal end of the inner hole A-56 that penetrates the needle tip protector A-10. The internal horizontal dimension of the internal space A-66 gradually increases toward the proximal end.

[0068] The wide portions A-64, 64 are formed with through windows A-68, 68 as engaging portions that penetrate in the plate thickness direction. The circumferential dimension of the through windows A-68, 68 is larger than the circumferential dimension of the hooks A-52, 52. In this embodiment, when molding the needle tip protector A-10, the mold for molding the outer peripheral surface is split in the vertical direction, so the through windows A-68, 68 are shaped so that no undercut occurs when the mold is removed in the vertical direction.

[0069] The narrow width portions A-62, 62 have an outer peripheral surface with a substantially elliptical cross section, and an inner peripheral surface that is substantially flat and perpendicular to the opposing direction of the narrow width portions A-62, 62. As a result, the narrow width portions A-62, 62 gradually become thicker toward the center in the circumferential direction, and the central portion in the circumferential direction becomes the thick-walled portion A-70, 70. In other words, the needle tip protector A-10 includes the thick-walled portion A-70, 70 that includes a portion whose thickness is greater than the thickness of the tip portion.

[0070] As shown in Figure 7, the thickness dimension of the thick-walled portions A-70,70 of the narrow portions A-62,62 includes portions that are larger than the thickness dimensions of the cylindrical portion A-58 and the wide portions A-64,64. The narrow portions A-62,62, which have a smaller diameter than the wide portions A-64,64, are thicker than the wide portions A-64,64 at least in the thick-walled portions A-70,70, so that the internal space A-66 of the expanded portion A-60 has a horizontally elongated flattened shape with a larger flattening ratio than the outer peripheral surface of the expanded portion A-60 when viewed in the axial direction of the peripheral wall A-54. In addition, the peripheral wall portion of the base-end opening A-57 is configured to include thick-walled portions A-70,70 on the narrow portions A-62,62 side and bridge portions A-71,71 on the wide portions A-64,64 side. The bridge portion A-71 is a portion of the wide portion A-64 that extends circumferentially on the base end side of the through window A-68, and its inner shape is a roughly arc shape. The peripheral wall A-54 at the base end of the needle tip protector A-10 and the inner shape of the bridge portions A-71, 71 correspond to each other. By configuring it in this way, it is possible to avoid thinning of the connection points between the bridge portions A-71, 71 and the thick portions A-70, 70, making it easier to ensure strength.

[0071] As shown in Figures 1 and 5, recesses A-72 are open on the outer surfaces of the thick-walled portions A-70 and 70 on both the upper and lower sides. The recesses A-72 and 72 have a substantially rectangular opening shape. The recesses A-72 and 72 are provided at the tip portions of the thick-walled portions A-70 and 70, and are notched recesses that open on the outer peripheral surface and tip surface that constitute the outer surface of the thick-walled portions A-70 and 70, respectively. It is desirable that the opening edges of the recesses A-72 and 72 have a curved cross-sectional shape without corners. The bottom surfaces of the recesses A-72 and 72 are flat surfaces that extend substantially perpendicular to the vertical direction, and the depth dimension gradually decreases toward the tip side.

[0072] A recess A-74 opens into the outer surface of the upper thick portion A-70. The recess A-74 has a substantially rectangular opening shape. The recess A-74 is a notched recess that opens into the outer peripheral surface and the base end surface that form the outer surface of the thick portion A-70. It is desirable that the opening edge of the recess A-74 has a curved cross-sectional shape without corners. The recess A-74 is located in a circumferentially central portion between the through windows A-68, 68, separated in the circumferential direction. At the portion of the thick portion A-70 where the recess A-74 is formed, the bottom wall of the recess A-74 is preferably thicker than the cylindrical portion A-58, but may be thinner than the cylindrical portion A-58. The depth of the recess A-74 is smaller than the maximum depth of the recess A-72. This prevents the expansion portion A-60 from becoming excessively thin due to the formation of the recess A-74, and ensures the strength required for the needle tip protector A-10 at the expansion portion A-60. The expansion portion A-60 of the needle tip protector A-10 is where the locking pieces A-78, 78 (flexible pieces) described below are arranged, and it is important to provide the expansion portion A-60 with the necessary strength in order to enhance the safety of the needle tip protector A-10. Furthermore, the depth dimension of the recess A-74 may be greater than the maximum depth dimension of the recess A-72. This makes it possible to increase the strength of the peripheral wall A-54 at the portion where the recess A-72 is formed compared to the portion where the recess A-74 is formed, thereby ensuring the necessary strength on the tip side of the recess A-74.

[0073] As shown in Figure 4, the inner peripheral surface of the peripheral wall A-54 is formed with an annular stepped surface A-76 that expands in the axis-perpendicular direction at the front end portion of the expanding portion A-60. The inner peripheral surface of the peripheral wall A-54 has a larger diameter on the distal side of the stepped surface A-76 than on the proximal side. The dimension of the stepped surface A-76 in the axis-perpendicular direction is smaller than the dimension of the distal restriction surface A-40 of the locking recess A-34 in the axis-perpendicular direction.

[0074] The peripheral wall A-54 is also provided with a pair of locking pieces A-78 (flexible pieces) that protrude from the inner circumferential surface of the expanded portion A-60 into the internal space A-66. As shown in FIG. 4, the locking pieces A-78 are integrally formed with the wide portions A-64 in the expanded portion A-60 of the peripheral wall A-54. The locking pieces A-78 are arranged on the inner circumferential side of the wide portions A-64 at positions corresponding to the wide portions A-64. The locking pieces A-78 are arranged opposite each other in the horizontal direction and are spaced apart from each other in the circumferential direction. The locking pieces A-78 protrude toward the base end of the peripheral wall A-54 on the base end side of the stepped surface A-76. The locking pieces A-78, 78 extend from the stepped surface A-76 toward the base end side substantially parallel to the needle axis direction, and at least the protruding tip portion is arranged away from the wide portions A-64, 64 of the peripheral wall A-54 toward the inner circumferential side. The locking pieces A-78, 78 are each curved in the circumferential direction. The locking pieces A-78, 78 are flexible plate-like members. The number of locking pieces A-78, 78 is not limited to a pair, and at least one may be provided.

[0075] A pair of locking claws A-80, 80 are formed at the protruding tips (proximal ends in the needle axis direction) of the locking pieces A-78, 78, bending inward and protruding. The inner peripheral surfaces of the locking claws A-80, 80 are curved in the circumferential direction, as shown in FIG. 7, and the radius of curvature of the inner peripheral surfaces at the protruding tips of the locking claws A-80, 80 is approximately equal to the radius of curvature of the outer peripheral surface of the small-diameter cylindrical portion A-32 of the needle support portion A-24. The radial distance between the opposing surfaces at the protruding tips of the locking claws A-80, 80 is approximately equal to the outer diameter of the small-diameter cylindrical portion A-32, but is smaller than the maximum outer diameter of the tip portion of the tapered surface A-30. However, the radial distance between the opposing surfaces at the protruding tips of the locking claws A-80, 80 may be slightly smaller or larger than the outer diameter of the small-diameter cylindrical portion A-32.

[0076] As shown in FIG. 4, the proximal end surfaces A-82, 82 of the locking claws A-80, 80 have inner peripheral small wall portions A-82a, 82a that expand in the axis-perpendicular direction, and outer peripheral portions that form inclined surfaces A-82b, 82b that slope toward the distal end in the needle axial direction. In this embodiment, the axis-perpendicular dimension of the small wall portions A-82a, 82a is approximately the same as or slightly larger than the axis-perpendicular dimension of the proximal restriction surface A-38 of the locking recess A-34. As a result, when the locking claws A-80, 80 abut against the proximal restriction surface A-38, as described below, the entire surface of the proximal restriction surface A-38 abuts against the small wall portions A-82a, 82a, ensuring a sufficiently large contact area. Furthermore, the inclined surfaces A-82b, 82b located on the outer periphery of the small wall portions A-82a, 82a are inclined toward the tip side in the needle axial direction as they approach the outer periphery, so that the small wall portions A-82a, 82a and the base end regulating surface A-38 abut without interference from the inclined surfaces A-82b, 82b.

[0077] In addition, the protruding tips (base ends in the needle axial direction) of the locking claws A-80, 80 are located further to the tip side in the needle axial direction than the base end of the widening portion A-60. Therefore, the entirety of the locking pieces A-78, 78 is housed in the internal space A-66 of the widening portion A-60.

[0078] The outer peripheral shape of the needle tip protector A-10 is formed, for example, by a mold A-88 including split dies A-84 and 86 assembled perpendicular to the axis, as shown in FIG. 8. Because the outer peripheral surface of the needle tip protector A-10 is molded by split dies A-84 and 86 assembled vertically, a parting line A-92 protruding from the parting surface A-90 of the split dies A-84 and 86 is formed extending axially on the horizontal outer surface of the needle tip protector A-10, as shown in FIG. 3. This makes it difficult for the parting line A-92 to come into contact with the patient, thereby avoiding pain caused by contact with the parting line A-92. Furthermore, by configuring the needle tip protector A-10 without a parting line A-92, pain caused by contact with the parting line A-92 can be avoided.

[0079] When molding the needle tip protector A-10, the injection gate mark A-98, which is the mark of the injection gate A-96 used to fill the resin material into the cavity A-94 of the mold A-88, is provided on the outer surface of the thick portion A-70, which is the circumferential center of one narrow portion A-62, as shown in Figures 1 and 5. In this embodiment, the injection gate A-96 is provided at one location in the circumferential direction, and the injection gate mark A-98 is provided on the inner surface of a recess A-74 opening into the outer surface of the upper thick portion A-70. By providing the injection gate A-96 at one location on the narrow portion A-62, weld lines can be prevented from occurring in the narrow portion A-62 on the injection gate A-96 side, while also preventing weld lines from occurring in the bridge portions A-71 and A-71, which are prone to being thin. As a result, the strength of the bridge portions A-71 and A-71 can be improved. Since the injection gate mark A-98 is located in the narrow portion A-62, it is located circumferentially away from the through windows A-68, 68 and locking pieces A-78, 78 located on the wide portion A-64, 64 side.

[0080] As can be seen from Figure 8, the resin material injected from the injection gate A-96 is injected into the cavity A-94 from the portion molding the thick portion A-70. This causes the resin material to fill the cavity A-94 from the wide portion with a large cross-sectional area toward the narrow portion with a small cross-sectional area. Therefore, when the resin material is filled into the cavity, poor filling of the resin material due to pressure loss is unlikely to occur, and the needle tip protector A-10 can be manufactured with consistent quality.

[0081] The cross-sectional area of ​​the needle tip protector A-10 in the axial direction or transverse direction is preferably equal to or smaller than the cross-sectional area at the injection gate mark A-98 on the proximal side of the injection gate mark A-98, and is also preferably equal to or smaller than the cross-sectional area at the injection gate mark A-98 on the distal side of the injection gate mark A-98. However, this is not limited to this embodiment, and a portion where the cross-sectional area is larger than the cross-sectional area at the injection gate mark A-98 may be provided between the injection gate mark A-98 and the distal or proximal end of the needle tip protector A-10. Furthermore, it is preferable that the amount of change in the cross-sectional area (volume) be gradual. However, this is not limited to this embodiment, and as long as voids, sink marks, etc. are not generated, the cross-sectional area (volume) may change stepwise, or there may be a portion where the cross-sectional area (volume) does not change gradually.

[0082] Furthermore, by keeping the injection gate mark A-98 contained within the recess A-74, the position of the injection gate A-96 can be set at the base end portion of the needle tip protector A-10, which has a thick wall and a large diameter, while preventing contact with the injection gate mark A-98 by the patient or the like, thereby enabling the needle tip protector A-10 to be manufactured efficiently.

[0083] The injection gate A-96 is a pin gate that is pulled off when the split molds A-84, 86 are removed. As a result, the injection gate mark A-98 is likely to be formed protruding from the bottom surface of the recess A-74, which is likely to cause discomfort or pain when the needle assembly A-12 is placed on the skin. The protruding height of the injection gate mark A-98 is smaller than the depth of the recess A-74, and the injection gate mark A-98 protruding from the bottom surface of the recess A-74 is located closer to the bottom than the open end surface of the recess A-74 and is contained within the recess A-74.

[0084] The injection gate mark A-98 has a lower translucency than the other parts of the peripheral wall A-54 when pulled off. That is, the injection gate mark A-98 absorbs more visible light passing through it than the other parts of the peripheral wall A-54, resulting in a lower transparency. This makes the injection gate mark A-98 easy to visually confirm. Therefore, for example, the position of the injection gate mark A-98 can be used as a mark for visually determining the circumferential orientation of the needle tip protector A-10 relative to the puncture needle body A-14.

[0085] When the injection gate trace A-98 is provided on the outer peripheral surface of the expansion portion A-60, it is desirable that it be provided in a direction approximately perpendicular to the tangent direction of the outer peripheral surface in the cross section of the expansion portion A-60. More preferably, when the injection gate trace A-98 is provided on the outer peripheral surface of the expansion portion A-60, it is provided on at least one of the minor and major axes of the elliptical cylindrical expansion portion A-60. This makes it easier for the resin injected from the injection gate A-96 into the cavity A-94 of the mold A-88 to be distributed uniformly within the cavity A-94, making it less likely that molding defects such as shrinkage cavities will occur.

[0086] Furthermore, the portion of the inner peripheral surface of the expanded portion A-60 corresponding to the injection gate mark A-98 may be formed into a concave shape so as to project toward the injection gate mark A-98. In this way, the resin injected into the cavity A-94 from the injection gate A-96 is guided to both sides in the circumferential direction by the convex portions of the mold A-88 that molds the concave shape, making it easier for the resin material to reach both sides in the circumferential direction of the cavity A-94, and reducing the likelihood of molding defects.

[0087] The mold for molding the needle tip protector A-10 includes split dies A-84, 86 as well as ejector pins A-100, 100 for demolding. The ejector pin A-100 extends vertically, which is the demolding direction of the split dies A-84, 86, and its protruding tip surface forms part of the inner wall surface of the cavity A-94. After molding of the resin molded product is completed, the split dies A-84, 86 are opened and the ejector pins A-100, 100 push out the resin molded product, thereby removing the resin molded product (needle tip protector A-10) from the split die A-84. In this way, the inner wall surface of the cavity A-94 is partially formed by the tip surfaces of the ejector pins A-100, 100, and as shown in Figure 2, two ejector pin marks A-102, 102 are formed on the outer circumferential surface of the needle tip protector A-10. The ejector pin marks A-102, 102 are shallow circular recesses. The protruding pin marks A-102, 102 are formed on the underside of the needle tip protector A-10, one of which is provided on the underside of the cylindrical portion A-58, and the other is provided on the outer peripheral surface of the lower thick-walled portion A-70 of the expanded portion A-60. Since such protruding pin marks A-102, 102 are provided in part of the circumferential direction, the protruding pin marks A-102, 102 can also be used as marks for identifying the circumferential orientation of the needle tip protector A-10. The formation position of the protruding pin marks A-102 is not particularly limited, and one or three or more protruding pin marks A-102 may be provided.

[0088] As shown in Figure 1, the tip portion of the needle tip protector A-10 is provided with a wing-like portion A-104. The wing-like portion A-104 is formed, for example, from a soft resin. The wing-like portion A-104 is formed integrally with a cylindrical fitting portion A-106, with plate-like connecting portions A-108, 108 protruding tangentially from the fitting portion A-106, and a wing main body A-110 is formed integrally with each of the connecting portions A-108, 108 at the tip end thereof protruding from the fitting portion A-106. The wing-like portion A-104 is attached to the peripheral wall A-54 of the needle tip protector A-10 by fitting the fitting portion A-106 externally onto the tip portion of the cylindrical portion A-58. In addition, Figure 7 shows a resin molded product of the needle tip protector A-10 before the wing-like portion A-104 is attached, and the wing-like portion A-104, which is a separate part, is attached in an extrapolated state to the needle tip protector A-10 in Figure 7.

[0089] The puncture needle body A-14 is inserted through the inner hole A-56 of the needle tip protector A-10 from the opening on the proximal end side, and the needle tip protector A-10 is fitted onto the puncture needle body A-14 to form the needle assembly A-12. In the initial state before use of the needle assembly A-12 shown in Figure 1 etc., the needle tip A-20 of the puncture needle body A-14 is located further distal than the needle tip protector A-10, and the needle tip A-20 is exposed. In this initial state, as shown in Figure 4, the hooks A-52, 52 provided on the needle hub A-18 of the puncture needle body A-14 are inserted into and engaged with the through windows A-68, 68 provided in the expanded portion A-60 of the needle tip protector A-10. This connects the needle tip protector A-10 and the needle hub A-18, maintaining the protruding state of the needle tip A-20, and restricting the movement of the puncture needle A-16 toward the base end in the needle axial direction due to resistance during puncture, for example, when holding the wing-shaped portion A-104 and performing a puncture.

[0090] In the initial state of the needle assembly A-12, the locking claws A-80, 80 of the needle tip protector A-10 abut against the outer peripheral surface of the small-diameter cylindrical portion A-32 of the needle support portion A-24. Note that these locking claws A-80, 80 may be slightly pressed outward by abutting against the outer peripheral surface of the small-diameter cylindrical portion A-32, or may be slightly spaced apart from the outer peripheral surface of the small-diameter cylindrical portion A-32.

[0091] The needle assembly A-12 is used for infusion, blood collection, and hemodialysis through the fluid flow path A-48 by inserting the puncture needle A-16 into a patient's blood vessel and leaving the puncture needle body (indwelling needle) 14 indwelling. Since the needle assembly A-12 of this embodiment is provided with winged portions A-104, it is possible to insert the puncture needle A-16 of the puncture needle body A-14 while pinching the winged portions A-104, for example. When the puncture needle body A-14 is left indwelling in the inserted state, it can be fixed with tape at the position of the winged portions A-104, allowing it to be fixed with a wide contact area with the skin.

[0092] When the puncture needle body A-14 is indwelled, the circumferential center portion of the thick portion A-70 on the lower side (lower side in FIG. 7) of the needle tip protector A-10 comes into contact with the patient's skin. Therefore, the circumferential center portion of the lower surface of the lower thick portion A-70 serves as the contact portion A-112 in this embodiment. A recess A-72 opens into the contact portion A-112. At least a portion of the inner surface of the recess A-72 does not come into contact with the patient, thereby reducing the contact area of ​​the contact portion A-112 with the patient. This reduces pain and discomfort when the contact portion A-112 comes into contact with the patient. In particular, if the opening edge of the recess A-72 has a curved cross-sectional shape without corners, the opening edge of the recess A-72 is less likely to catch on the patient's skin, thereby reducing pain and discomfort caused by contact with the opening edge of the recess A-72. Furthermore, the injection gate mark A-98 is provided on the thick portion A-70 on the upper side (upper side in Fig. 7) opposite to the contact portion A-112 with the patient, and is positioned away from the contact portion A-112, so it does not come into contact with the patient's skin. In Fig. 5, the surface of the patient's body when the puncture needle body A-14 has been inserted into the patient and left in place is virtually illustrated by a two-dot chain line.

[0093] Furthermore, when a medical professional touches the thick-walled portions A-70, 70 of the needle tip protector A-10 during the puncture of the puncture needle body A-14 or the removal operation described below, the opening area of ​​the recess A-74 opening on the outer surface of the thick-walled portion A-70 is sufficiently small to make it difficult for the fingertip to be inserted deep into the recess A-74. This makes it difficult for the medical professional to touch the injection gate mark A-98 protruding from the bottom surface of the recess A-74, and reduces the pain and discomfort caused by contact with the injection gate mark A-98. In particular, if the opening edge of the recess A-74 has a curved cross-sectional shape without corners, the opening edge of the recess A-74 is less likely to catch on the fingertip of the medical professional, thereby reducing the pain and discomfort caused by contact with the opening edge of the recess A-74.

[0094] When removing the puncture needle body A-14, the engagement arms A-50, 50 of the needle hub A-18 are pressed inward with the fingers while the needle tip protector A-10 remains fixed with tape to the wing-like portion A-104. This releases the engagement between the hooks A-52, 52 and the through windows A-68, 68, allowing the puncture needle body A-14 to be moved toward the base end relative to the needle tip protector A-10. By moving the puncture needle body A-14 toward the base end relative to the needle tip protector A-10 and removing the puncture needle A-16 from the skin, the needle tip protector A-10 moves toward the needle tip A-20 relative to the puncture needle body A-14.

[0095] With the hooks A-52, 52 and the through windows A-68, 68 in a released state, the puncture needle A-14 will not move toward the base end relative to the needle tip protector A-10 unless an external force is applied to the puncture needle A-14 to move it toward the base end relative to the needle tip protector A-10. That is, the locking claws A-80, 80 abut against the tapered surface A-30, which becomes larger in diameter toward the tip end, preventing the puncture needle A-14 from moving toward the base end relative to the needle tip protector A-10. This prevents the needle tip A-20 of the puncture needle A-14 from being unintentionally protected by the needle tip protector A-10.

[0096] By moving the puncture needle A-14 toward the base end relative to the needle tip protector A-10, the locking claws A-80, 80 slide against the tapered surface A-30, and the elastic restoring force of the locking pieces A-78, 78 acts as a biasing force pressing the locking claws A-80, 80 against the tapered surface A-30. Therefore, the user can move the puncture needle A-14 while feeling the resistance caused by the contact between the locking claws A-80, 80 and the tapered surface A-30, confirming the feeling that the puncture needle A-14 is being pulled out of the needle tip protector A-10.

[0097] As shown in Figure 9, by moving the puncture needle body A-14 backward to a predetermined position relative to the needle tip protector A-10 (moving the needle tip protector A-10 forward toward the needle tip A-20 of the puncture needle body A-14), the needle tip A-20 of the puncture needle A-16 is covered by the needle tip protector A-10. Furthermore, the locking claws A-80, 80 provided on the free ends of the locking pieces A-78, 78 move over the opening of the locking recess A-34, causing the locking claws A-80, 80 to elastically restore their shape and enter the locking recess A-34. As a result, the small wall portions A-82a, 82a of the locking claws A-80, 80 come into contact with and lock against the base-end restriction surface A-38 of the locking recess A-34. Then, the movement of the puncture needle body A-14 toward the tip side relative to the needle tip protector A-10 is restricted, and the needle tip A-20 of the puncture needle body A-14 is prevented from being exposed again.

[0098] The stepped surface A-76 provided at the front end portion of the locking pieces A-78, 78 comes into contact with and locks against the tip-side restricting surface A-40 of the locking recess A-34, thereby restricting the movement of the puncture needle A-14 toward the base end. This prevents the puncture needle A-14 from being pulled out toward the base end relative to the needle tip protector A-10. Therefore, movement of the puncture needle A-14 in both axial directions relative to the needle tip protector A-10 is prevented, and the protection of the needle tip A-20 by the needle tip protector A-10 is maintained.

[0099] In this embodiment, a pair of locking pieces A-78, 78 are provided, and together with the fact that the locking pieces A-78, 78 are integrally molded with the peripheral wall A-54 of the needle tip protector A-10, when the locking claws A-80, 80 and the proximal-end regulating surface A-38 are engaged, problems such as rattling of the needle tip protector A-10 relative to the puncture needle body A-14 can be effectively prevented. In this way, by providing two or more locking pieces A-78, the needle tip protector A-10 is more reliably prevented from retracting toward the proximal end relative to the puncture needle body A-14, and the effect of preventing re-exposure of the needle tip A-20 can be more stably achieved. In this case, it is preferable that the multiple locking pieces A-78 be arranged approximately symmetrically with respect to the central axis of the needle tip protector A-10.

[0100] With the needle tip A-20 of the puncture needle body A-14 protected by the needle tip protector A-10, the tape fixing of the winged portion A-104 is released and the needle assembly A-12 is removed from the patient. However, the procedure for protecting the needle tip A-20 is not limited to the above procedure. Specifically, for example, the tape fixing of the winged portion A-104 may be released, the entire needle assembly A-12 may be moved back to remove the puncture needle A-16 from the blood vessel, and then the puncture needle body A-14 may be moved back relative to the needle tip protector A-10 to protect the needle tip A-20 of the puncture needle A-16.

[0101] When the locking claws A-80, 80 enter the locking recess A-34, the tips of the locking claws A-80, 80 come into contact with the bottom surface of the locking recess A-34, allowing the user to hear the impact and sound of this contact. This avoids the possibility that the user will stop the operation of pulling out the puncture needle body A-14 midway, and the protection of the needle tip A-20 by the needle tip protector A-10 can be more reliably achieved.

[0102] In the needle tip protector A-10 and needle assembly A-12 constructed as described above, the entirety of the locking pieces A-78, 78 that prevent the needle tip A-20 of the puncture needle body A-14 from being re-exposed is housed inside the cylindrical peripheral wall A-54. Therefore, it is made nearly impossible to unintentionally contact the locking pieces A-78, 78 from the outside. Therefore, when the needle tip A-20 of the puncture needle body A-14 is protected by the needle tip protector A-10, it is possible to effectively prevent the needle tip A-20 from being re-exposed from the needle tip protector A-10 by unintentionally releasing the lock between the locking pieces A-78, 78 and the locking recess A-34.

[0103] When the locking pieces A-78, 78 are locked to the needle hub A-18, for example, if an external force in a bending direction is applied to the needle tip protector A-10 and / or the needle hub A-18, the locking pieces A-78, 78 can come into contact with the wide portions A-64, 64 located away from the outer periphery. This limits the deformation of the locking pieces A-78, 78 toward the outer periphery, reducing the risk of the locking pieces A-78, 78 being released from their locking to the needle hub A-18, and therefore the protection state of the needle tip A-20 of the puncture needle body A-14 can be stably maintained.

[0104] The locking pieces A-78, 78 are provided on an expanded portion A-60 that is expanded at the base end side of the needle tip protector A-10. This allows the size of the locking pieces A-78, 78 to be sufficiently ensured while also allowing the outer diameter dimension of the needle support portion A-24 of the needle hub A-18, which is inserted between the locking pieces A-78, 78, to be sufficiently large. Furthermore, in this embodiment, the expanded portion A-60 has a flattened, approximately elliptical shape, and its outer peripheral surface smoothly continues from the outer peripheral surface of the cylindrical portion A-58, thereby reducing the risk of the expanded portion A-60 or the like coming into contact with the patient and causing pain to the patient.

[0105] Furthermore, in a cross-sectional view in the transaxial direction, the expansion portion A-60 is configured so that the curvature of the curve in the direction corresponding to the recess A-72 or the recess A-74 is gentler than the curvature of the curve in the direction corresponding to the locking pieces A-78, 78. In other words, the recess A-72 or the recess A-74 is configured in a part where the curvature of the expansion portion A-60 is gentler than the curvature of the curve in the direction corresponding to the locking pieces A-78, 78. This part is the part that may come into contact with the patient when placed in place, and is likely to cause pain and discomfort to the patient due to contact, but by configuring it in this way, the recess A-72 or the recess A-74 reduces the contact area with the patient, thereby further reducing pain and discomfort during placement.

[0106] In addition, the injection gate mark A-98 is provided on the surface of the needle tip protector A-10 opposite to the surface on which the wing body A-110 of the wing-like portion A-104 is located. With this configuration, the injection gate mark A-98, which is likely to cause pain to the patient when it comes into contact with the patient, is provided in a position that is less likely to come into contact with the patient, thereby reducing pain and discomfort during placement. Furthermore, by providing the injection gate mark A-98 in the recess A-72 or recess A-74 provided on the surface on the opposite side to the surface on which the wing body A-110 is located, pain and discomfort during placement can be further reduced.

[0107] Since the locking pieces A-78, 78 are provided inside the wide portions A-64, 64 that constitute the expansion portion A-60, the wide portions A-64, 64 are prevented from becoming thick, thereby suppressing the incorporation of air bubbles into the member during molding and the occurrence of voids and sink marks, resulting in dimensional errors and deterioration in quality. Also, it is preferable that the locking portions (locking pieces A-78, 78) are provided so as to extend in the same direction (toward the base end in the axial direction) as the wide portions A-64, 64. This prevents the expansion portion A-60 from becoming larger than necessary, makes it possible to effectively utilize the space inside the wide portions A-64, 64, and prevents the wide portions A-64, 64 from becoming thick.

[0108] Since the locking pieces A-78, 78 extend toward the base end side, they do not get caught when the puncture needle body A-14 is pulled out from the needle tip protector A-10, and smooth pulling out can be achieved.

[0109] The small wall portions A-82a, 82a (first locking portion) of the locking claws A-80, 80, which are locked to each other, and the base-end regulating surface A-38 (third locking portion) of the locking recess A-34, both extend in the direction perpendicular to the axis. Furthermore, the stepped surface A-76 (second locking portion) and the tip-end regulating surface A-40 (fourth locking portion) of the locking recess A-34, which are locked to each other, both extend in the direction perpendicular to the axis. Therefore, the needle tip protector A-10, which has the small wall portions A-82a, 82a and the stepped surface A-76, and the needle hub A-18, which has the base-end regulating surface A-38 and the tip-end regulating surface A-40, are free from undercuts and are easy to mold. Moreover, the contact force and contact reaction force due to the contact between the small wall portions A-82a, 82a and the base-end side control surface A-38 act without tilting relative to the axial direction. Similarly, the contact force and contact reaction force due to the contact between the stepped surface A-76 and the tip-end side control surface A-40 act without tilting relative to the axial direction. Furthermore, the contact areas of each can be sufficiently secured, so that the needle tip protector A-10 can be more reliably prevented from moving toward the tip end and the base end relative to the puncture needle A-14.

[0110] An expanded portion A-60 is provided at the base end of the peripheral wall A-54 of the needle tip protector A-10, and in the expanded portion A-60, wide portions A-64,64 with larger outer diameters are provided with through windows A-68,68 and locking pieces A-78,78, while an injection gate trace A-98 is provided in the narrow portion A-62 with smaller outer diameters in the expanded portion A-60. This makes it easier to ensure space in the wide portions A-64,64 for providing the through windows A-68,68 and locking pieces A-78,78. The narrow portions A-62,62 have greater freedom in shape and make it easier to provide the thick portion A-70, compared to the wide portions A-64,64, which are limited in shape by providing the through windows A-68,68 and locking pieces A-78,78.

[0111] Figure 10 shows a needle assembly A-122 equipped with a needle tip protector A-120 as a second embodiment of invention A. In the following description, the same components and parts as those in the first embodiment of invention A are denoted by the same reference numerals in the drawings and description thereof will be omitted.

[0112] The needle tip protector A-120 has recesses A-74, 74 formed in the thick portions A-70, 70 on both the upper and lower sides, and an injection gate mark A-98 is formed on the bottom surface of each recess A-74. In short, the needle tip protector A-120 has a plurality of injection gate marks A-98, and these plurality of injection gate marks A-98, 98 are formed within the recesses A-74, 74, respectively.

[0113] Therefore, when molding the needle tip protector A-120, the resin material is filled into the cavity (not shown) from two points in the circumferential direction, which makes it less likely that the resin material will be filled improperly when molding the needle tip protector A-120, and makes it possible to stably obtain needle tip protectors A-120 in the desired shape.

[0114] In addition to the recess A-72, a depression A-74 opens into the contact portion A-112, which is provided on the underside of the lower thick portion A-70 and which may come into contact with the patient's skin. At least the bottom of the inner surface of this depression A-74 does not come into contact with the patient's skin, and the bottom of the depression A-74 is located outside the contact portion A-112. Therefore, the injection gate mark A-98 protruding from the bottom of the depression A-74, which opens into the contact portion A-112, is located outside the contact portion A-112. As a result, even if the injection gate mark A-98 is formed on the contact portion A-112 side, the injection gate mark A-98 is prevented from coming into contact with the patient, thereby avoiding pain or discomfort caused by contact with the injection gate mark A-98.

[0115] The number of injection gate marks A-98 may be three or more. When multiple injection gate marks A-98 are formed, at least one of the injection gate marks A-98 may be formed on the outer surface of the thick portion A-70 at a position outside the recess A-74.

[0116] Although the embodiments of Invention A have been described above in detail, Invention A is not limited to the specific descriptions. For example, in the above embodiment, the recesses A-72, 72 and the recess A-74 are provided so as to open to the outer peripheral surface of the thick-walled portion A-70, 70, but the recesses can also be provided so as to open to the axial end surface of the thick-walled portion A-70. Specifically, a recess may be provided so as to open to the axial direction in the base end surface of the thick-walled portion A-70 provided at the base end of the peripheral wall A-54.

[0117] In the above embodiment, the recess is composed of both the recess A-72 without the injection gate mark A-98 and the recess A-74 with the injection gate mark A-98, but the recess may be composed of only one of them. Furthermore, the number and arrangement of the recesses A-72 and A-74 may be changed as appropriate. Specifically, for example, there may be only one recess A-72, or there may be two or more recesses A-74. Furthermore, the recess does not have to be provided. Furthermore, the injection gate mark A-98 may be provided in the recess A-72.

[0118] In the above embodiment, the outer peripheral surface of the peripheral wall A-54 of the needle tip protector A-10 is molded using split molds A-84 and A-86. However, the outer peripheral surface of the peripheral wall of the needle tip protector can also be molded using a die as shown in FIG. 11. The mold A-130 used to mold the outer peripheral surface of the needle tip protector shown in FIG. 11 has a cylindrical cavity wall inner surface and is a die that is demolded in the axial direction. Therefore, the outer peripheral surface of the peripheral wall of the molded needle tip protector does not have a parting line extending in the axial direction. This makes it possible to set the parting line in a location that is difficult for patients, medical professionals, etc. to touch in the axial direction, thereby making the surface shape of the part that is easily touched by patients, medical professionals, etc. smoother. Therefore, when patients, medical professionals, etc. touch the needle tip protector, it is difficult for them to touch the burr-like parting line, thereby further reducing pain and discomfort.

[0119] In addition, the injection gate A-134 that injects the resin material into the cavity A-132 of the mold A-130 in Figure 11 is a tunnel gate that cuts the runner in the shear direction by the mold A-130 when the mold A-130 is removed from the molded product (needle tip protector).By using a tunnel gate, the length of the runner can be shortened, allowing a molded product to be obtained efficiently using a small amount of resin material.

[0120] The injection gate mark A-98 is preferably formed on the inner surface of the recess, but may be formed on the outer surface of the thick portion A-70 at a position outside the recess without being contained in the recess.

[0121] The injection gate trace A-98 may be provided on the outer peripheral surface of the thick-walled portion A-70, or on the axial end surface of the thick-walled portion A-70. In other words, the outer surface of the thick-walled portion A-70 does not only refer to the outer peripheral surface, but also includes both the outer peripheral surface and the axial end surface.

[0122] Specifically, for example, as in the needle tip protector A-140 shown in FIG. 12, a recess A-142 opening to the axial base end surface of the expanded portion A-60 may be formed, and an injection gate mark A-98 may be formed on the bottom surface of the recess A-142. In the needle tip protector A-140, the injection gate mark A-98 is provided on each of the axial end surfaces of the narrow portions A-62, 62 of the expanded portion A-60. However, as in the needle tip protector A-150 shown in FIG. 13, the recess A-142 and the injection gate mark A-98 may also be provided on the base end surface of the wide portions A-64, 64 of the expanded portion A-60. In addition, in the needle tip protector A-150 shown in FIG. 13, the circumferential central portion of the wide portions A-64, 64 is formed as a thick portion A-70 that is thicker than both end portions.

[0123] As shown in FIG. 13, by providing the injection gate A-96 (injection gate mark A-98) on the wide portion A-64, 64 side, it is possible to reduce the occurrence of weld lines in the wide portion A-64, 64, which serves as an engagement portion having a through window A-68, 68. By increasing the strength of the wide portion A-64, 64, it is possible to more firmly fix the engagement arm A-50 of the needle hub A-18 to the needle tip protector A-10. This prevents unintended separation of the needle tip protector A-150 and the needle hub A-18, thereby preventing malfunction of the needle tip protection mechanism. Furthermore, it is also possible to prevent malfunction of the needle tip protection mechanism, for example, due to damage to the wide portion A-64, 64 caused by external force. It is preferable that the injection gate A-96 (injection gate mark A-98) be provided on the proximal end side of the engagement portion. The engagement portion is often provided at the base end of the needle tip protector A-150, and because the strength of the base end of the needle tip protector A-150 is easily reduced, greater strength is required. Therefore, by configuring it in this way, it is possible to make it less likely for a weld line to form on the base end side of the engagement portion. As a result, the strength of the engagement portion is increased, further improving safety.

[0124] 12 and 13 show examples in which a pair of upper and lower or left and right injection gate marks A-98 are provided, but the number of injection gate marks A-98 and their arrangement on the axial end face are not limited. For example, in addition to the pair of upper and lower injection gate marks A-98, 98 shown in Fig. 12, a pair of left and right injection gate marks A-98, 98 shown in Fig. 13 may be provided, in which case the structure will have four injection gate marks A-98.

[0125] Furthermore, since the proximal end surface of the expansion portion A-60 is a non-contact portion that is unlikely to come into contact with the patient's skin, the injection gate mark A-98 may be provided so as to protrude from the proximal end surface of the needle tip protector without providing the recess A-142. However, before use, when the needle tip protector A-140, 150 is connected to a needle hub (not shown), the proximal end surface of the expansion portion A-60 is superimposed on the distal end surface of the needle hub. Therefore, it is desirable that the injection gate mark A-98 be provided so as to be housed within the recess A-142 without protruding from the proximal end surface of the expansion portion A-60, thereby preventing rattling between the needle tip protector A-140, 150 and the needle hub.

[0126] When the injection gate position is set so that the injection gate mark A-98 is formed on the base end surface of the expanded portion A-60, it is desirable that the injection gate mark A-98 be provided approximately parallel to the axial direction of the cylindrical needle tip protectors A-140, 150. This makes it easier for the resin injected from the injection gate into the cavity of the mold that molds the needle tip protectors A-140, 150 to spread evenly within the cavity, making it less likely that molding defects will occur.

[0127] In the above embodiment, an example was shown in which the injection gate mark A-98 was provided on the outer peripheral surface of the narrow portions A-62, 62. However, when the injection gate mark A-98 is provided on the outer peripheral surface of the wide portion A-60, the injection gate mark A-98 can also be provided on the outer peripheral surface of the wide portion A-64, as in the needle tip protector A-160 shown in Figure 14. Since the wide portion A-64 is located on the side (left-right direction) where it is difficult to come into contact with the patient, in the needle tip protector A-160, the injection gate mark A-98 is provided protrudingly without being housed in a recess. However, even when the injection gate mark A-98 is provided on the wide portion A-64, if a recess opening into the wide portion A-64 is formed and the injection gate mark A-98 is provided within the recess, the protrusion of the injection gate mark A-98 can be suppressed. When an injection gate mark A-98 is formed in the wide portion A-64 that forms the left and right side surfaces, as in the needle tip protector A-160, the injection gate mark A-98 may be provided in each of the pair of wide portions A-64, 64, or may be provided in only one of the wide portions A-64.

[0128] As shown in FIG. 14, by providing the injection gate A-96 (injection gate mark A-98) on the wide portion A-64, 64 side, it is possible to reduce the likelihood of weld lines occurring in the wide portion A-64, 64, which serves as an engagement portion having a through window A-68, 68. By increasing the strength of the wide portion A-64, 64, it is possible to more firmly fix the engagement arm A-50 of the needle hub A-18 to the needle tip protector A-160. This prevents unintended separation of the needle tip protector A-160 and the needle hub A-18, thereby preventing malfunction of the needle tip protection mechanism. Furthermore, it is also possible to prevent malfunctions of the needle tip protection mechanism, such as when the wide portion A-64, 64 is broken by external force. It is preferable that the injection gate A-96 (injection gate mark A-98) be provided on the proximal end side of the engagement portion. The engagement portion is often provided at the base end of the needle tip protector A-160, and because the strength of the base end of the needle tip protector A-160 is easily reduced, greater strength is required. Therefore, by configuring it in this way, it is possible to make it less likely for a weld line to form on the base end side of the engagement portion. As a result, the strength of the engagement portion is increased, further improving safety.

[0129] It is also possible to use an appropriate combination of the injection gate mark A-98 provided on the outer surface of the thick-walled portion A-70 of the narrow portion A-62 shown in the needle tip protector A-10, the injection gate mark A-98 provided on the axial base end surface of the expanded portion A-60 shown in the needle tip protectors A-140 and A-150, and the injection gate mark A-98 provided on the outer surface of the wide portion A-64 shown in the needle tip protector A-160.

[0130] The number and arrangement of the injection gate marks A-98 are not particularly limited. For example, when a plurality of injection gate marks A-98 are provided, they may be arranged at positions shifted from each other in the axial direction.

[0131] The expansion portion A-60 is not essential, and for example, the outer diameter of the peripheral wall A-54 may be approximately constant in the axial direction, and the thick portion A-70 may be formed by changing the inner diameter. Also, the base end portion of the peripheral wall A-54 where the thick portion A-70 is provided may have a smaller diameter than the tip portion.

[0132] Although the example in which the locking piece A-78 is formed inside the area covered by the peripheral wall A-54 has been shown, it is not limited to this form, and the expanding portion A-60 may have a notch so that the locking piece A-78 can be seen from the outside. Also, the locking piece A-78 may be provided in the recess A-72 or the depression A-74. The invention of the parent application originally includes each of the inventions described below in (i) to (xx), and the following additional notes are provided regarding their configurations and effects. The invention in the parent application is: (i) A needle tip protector made of resin and having a peripheral wall that moves in the needle axial direction relative to the puncture needle to cover the tip of the puncture needle, wherein the peripheral wall has a cylindrical portion on the distal end side, and the peripheral wall is provided with a thick portion on the proximal end side of the cylindrical portion that has a portion with a thickness greater than that of the cylindrical portion, and a trace of a resin material injection gate during molding is provided in the thick portion; (ii) The needle tip protector according to (i), wherein a recess is provided on the outer surface of the thick-walled portion. (iii) The needle tip protector according to (ii), wherein the injection gate mark is provided on the inner surface of the recess. (iv) The needle tip protector according to (ii) or (iii), wherein the depth dimension of the recess gradually decreases toward the tip side of the peripheral wall. (v) The needle tip protector according to any one of (ii) to (iv), wherein the opening edge of the recess has a curved cross-sectional shape without corners. (vi) A needle tip protector according to any one of (i) to (v), wherein the peripheral wall has an expanded portion on the base end side of the cylindrical portion that includes a portion that is thicker than the cylindrical portion and has larger outer dimensions, and the injection gate mark is provided on the outer surface of the expanded portion. (vii) A needle tip protector made of resin, which has a peripheral wall that moves in the needle axial direction relative to the puncture needle to cover the tip of the puncture needle, the peripheral wall having a cylindrical portion and an expanded portion having an outer dimension larger than that of the cylindrical portion, and a trace of an injection gate of resin material during molding is provided in the expanded portion; (viii) The needle tip protector according to any one of (i) to (vii), wherein the injection gate mark is provided at a position away from an engaging portion that engages with a needle hub provided on the base end side of the puncture needle. (ix) A needle tip protector according to any one of (i) to (viii), in which a locking piece is provided that is locked to a needle hub provided on the base end side of the puncture needle when the peripheral wall covers the needle tip of the puncture needle to prevent the needle tip from being re-exposed, and the injection gate mark is provided at a position away from the locking piece. (x) The needle tip protector according to any one of (i) to (ix), wherein the outer surface of the peripheral wall is formed by a split mold in the axis-perpendicular direction and has a parting line extending in the axial direction; (xi) The needle tip protector according to any one of (i) to (ix), wherein the outer surface of the peripheral wall is formed by an axial punching die and does not have a parting line extending in the axial direction. (xii) The needle tip protector according to any one of (i) to (xi), wherein a plurality of the injection gate marks are provided in the circumferential direction of the peripheral wall. (xiii) A needle tip protector according to any one of (i) to (xii), in which the outer dimensions of at least the base end of the peripheral wall in the axis-perpendicular direction are different in the circumferential direction, and in which the wide portion having the larger outer dimensions is provided with at least one of an engaging portion that engages with a needle hub fixed to the base end of the puncture needle and a locking piece that is locked to the needle hub to prevent the needle tip from re-projecting, and in which the injection gate mark is provided in the narrow portion having the smaller outer dimensions; (xiv) A needle tip protector according to any one of (i) to (xiii), wherein the peripheral wall is transparent or semi-transparent to allow light to pass through, and the light transmittance of the peripheral wall at the injection gate mark is lower than that of other parts of the peripheral wall. (xv) A needle assembly comprising a needle tip protector that covers the tip of the puncture needle by moving in the needle axial direction relative to a puncture needle body that has a puncture needle, wherein the needle tip protector is the needle tip protector described in any one of (i) to (xiv), and at least a part of the outer surface of the thick-walled part of the needle tip protector is a contact part that comes into contact with the patient's skin, and the contact part has an opening in the recess described in (ii). (xvi) The needle assembly according to (xv), wherein the contact portion comes into contact with the patient's skin when the puncture needle body is placed. (xvii) The needle assembly according to (xv) or (xvi), wherein the injection gate mark is provided at a position away from the contact portion. (xviii) A needle assembly according to any one of (xv) to (xvii), wherein a protruding pin mark is provided on the outer surface of the thick-walled portion of the needle tip protector at either the contact portion or a portion located on the radially opposite side of the contact portion. (xix) A needle assembly comprising a needle tip protector that covers the tip of the puncture needle by moving in the needle axial direction relative to a puncture needle body that has a puncture needle, wherein the needle tip protector is the needle tip protector described in (vi) or (vii), the expanded portion comprises a narrow portion and a wide portion that has an outer dimension larger than that of the narrow portion, the injection gate trace is provided on the wide portion side, and the needle tip protector comprises an engaging portion on the wide portion that is detachably engaged with an engaging arm provided on a needle hub fixed to the base end of the puncture needle; (xx) The needle assembly according to (xix), wherein the injection gate mark is provided on the proximal end side of the engagement portion. This includes inventions relating to: In the invention described in (i) above, during molding, an injection gate for the resin material is set in the portion where the thick portion of the peripheral wall is molded, and the resin material is filled in the cavity of the mold from the portion with the larger cross-sectional area to the portion with the smaller cross-sectional area. Therefore, when filling the cavity with the resin material, pressure loss due to changes in the cross-sectional area of ​​the cavity is unlikely to occur, and poor filling of the resin material can be avoided, making it possible to stably obtain a needle tip protector of the desired shape. The invention described in (ii) above can prevent the thick-walled portion from becoming excessively thick. As a result, defects such as the inclusion of air bubbles in the thick-walled portion and the occurrence of sink marks and voids can be avoided. For example, if the thickness of the thick-walled portion is not constant because the inner and outer surfaces of the thick-walled portion have different shapes, a recess can be provided on the outer surface of the thick-walled portion where the thickness is particularly thick. As a result, it is possible to prevent the thick-walled portion from becoming significantly thick in parts. In the invention described in (iii) above, for example, when the injection gate mark is protruding, the injection gate mark is provided on the inner surface of the recess, making it less likely to protrude outward from the outer surface of the thick-walled portion. This reduces the risk of the injection gate mark catching and causing pain when the thick-walled portion comes into contact with the patient's skin. Although the thickness of the peripheral wall is reduced where the recess is formed, forming the recess in a thick-walled portion that includes a thicker portion can prevent the peripheral wall from becoming excessively thin where the recess is formed. Therefore, even when providing the injection gate mark on the inner surface of the recess to prevent the injection gate mark from coming into contact with the patient, it is possible to effectively prevent insufficient filling of the resin material during molding, enabling the stable production of needle tip protectors of the desired shape. In the invention described in (iv) above, for example, when the position of the injection gate is set so that an injection gate mark is left on the inner surface of the recess, it is possible to avoid a sudden change in the filling pressure of the resin material during molding and therefore in the resin density during molding, thereby ensuring the strength of the needle tip protector and preventing molding defects such as sink marks. In the invention described in (v) above, when the opening edge of the recess comes into contact with the patient's skin, the patient is less likely to feel pain or discomfort. Furthermore, since the opening edge of the recess has a shape without corners, defects such as chipping of the opening edge of the recess are less likely to occur. In the invention described in (vi) above, by providing a thick-walled portion in which an injection gate mark is set in the expanded portion with an increased outer diameter, it is possible to prevent the inner diameter of the peripheral wall including the expanded portion from becoming significantly smaller in the thick-walled portion. In the invention described in (vii) above, during molding, a resin material injection gate is set in a portion where an expanded portion having an outer dimension larger than that of the cylindrical portion and a long circumferential length of the outer peripheral surface is molded, whereby the resin material can be filled with sufficient pressure in the portion of the cavity of the molding die that has a long circumferential length, and insufficient filling of the resin material can be avoided. In the invention described in (viii) above, the injection gate is set at a position away from the part where the shape becomes complex or the cross-sectional area becomes small due to the formation of the engagement portion, thereby making it possible to more effectively avoid molding defects. In the invention described in (ix) above, by making the portion of the peripheral wall away from the locking piece a thick portion, the portion of the peripheral wall where the locking piece is provided can be made relatively thin. As a result, it is possible to prevent air bubbles from being mixed into the locking piece and to prevent the occurrence of sink marks or voids. Furthermore, by setting the injection gate at a position away from the portion where the shape becomes complex or the cross-sectional area becomes small due to the formation of the locking piece, molding defects can be more effectively avoided. The invention described in (x) above allows for a great degree of freedom in the shape of the outer surface of the peripheral wall. If the injection gate position of the resin material is set so that an injection gate mark is formed on the outer surface of the peripheral wall, a pin gate can be used in which the runner is pulled and cut when the split mold is removed in the direction perpendicular to the axis, making it easier to mold multiple needle tip protectors simultaneously in a small space and improving the mass productivity of needle tip protectors. In the invention described in (xi) above, if the injection gate position of the resin material is set so that an injection gate mark is formed on the outer surface of the peripheral wall, a tunnel gate can be used in which the runner is cut by the die when the die is removed in the axial direction. Therefore, the needle tip protector can be manufactured using a relatively small amount of forming material. In the invention described in (xii) above, by filling the cavity of the mold with resin material from a plurality of locations in the circumferential direction during molding, imperfect filling of the resin material becomes less likely to occur. In the invention described in (xiii) above, the wide portion, which has a large outer dimension in the axis-perpendicular direction, can easily secure space for arranging at least one of the engaging portion and the locking portion. The narrow portion, which has a small outer dimension in the axis-perpendicular direction, can easily be made thicker than the wide portion in which the engaging portion and / or the locking portion are arranged, allowing for efficient filling of the resin material during molding. In the invention described in (xiv) above, the injection gate mark can be easily visually confirmed due to the difference in light transmittance, and therefore the orientation of the needle tip protector can be easily grasped using the injection gate mark as a landmark. In the invention described in (xv) above, a recess is provided in the contact portion of the needle tip protector, thereby reducing the area of ​​the contact portion that comes into contact with the patient's body surface, thereby reducing pain and discomfort caused by contact with the contact portion. In the invention described in (xvi) above, a recess is provided in the contact portion that comes into contact with the patient when the indwelling needle serving as the puncture needle body is placed, and the contact area of ​​the contact portion with the patient is reduced, thereby reducing the pain and discomfort felt by the patient due to contact with the contact portion during placement. In the invention described in (xvii) above, the injection gate mark is prevented from coming into contact with the patient, so that even if the needle tip protector comes into contact with the patient, the patient is less likely to experience pain or discomfort. In the invention described in (xviii) above, the protruding pin mark formed by the protruding pin of the mold used to remove the molded product from the mold is set to be located either at the contact part on the outer surface of the thick part of the needle tip protector or on the radially opposite side of the contact part, thereby making it possible to grasp the orientation of the contact part of the needle tip protector using the protruding pin mark as a mark. In the invention described in (xix) above, by providing an injection gate (injection gate trace) in the wide portion, it is possible to reduce the likelihood of weld lines forming at the engagement portion. As a result, the strength of the engagement portion of the needle tip protector is increased, allowing the engagement arm of the needle hub to be more firmly engaged with the needle tip protector. This avoids unintended separation of the needle hub and the needle tip protector, preventing malfunction of the needle tip protection mechanism. It also prevents problems such as the engagement portion being destroyed by external force, causing the needle tip protection mechanism to malfunction. In the above aspect (xix), the injection gate mark is preferably provided on the proximal side of the engagement portion. The engagement portion is often provided at the proximal end of the needle tip protector, and since the strength of the proximal end of the needle tip protector is easily reduced, greater strength is required. Therefore, by configuring it in this way, it is possible to make it less likely for a weld line to occur on the proximal side of the engagement portion. As a result, the strength of the engagement portion is increased, further improving safety.

[0133] [Invention B] 15 to 20 show a needle assembly that can be recognized as an independent invention B that can solve a problem different from that of invention A. Invention B relates to a puncture needle body in which a needle hub is provided on the base end side of the puncture needle, and a puncture needle assembly using the same.

[0134] Puncture needle bodies such as indwelling needles used for transfusions, blood sampling, hemodialysis, etc. have been known for some time. An indwelling needle has a structure in which a needle hub is fixed to the base end of a puncture needle with a sharp needle tip. The indwelling needle is inserted into a lumen in the body, such as a patient's blood vessel, and an external conduit is connected to the needle hub, allowing transfusions, blood sampling, hemodialysis, etc. to be performed through the lumen of the indwelling needle and the external conduit.

[0135] Incidentally, as disclosed in, for example, JP 2017-196060 A (Patent Document 1), an external conduit is connected to an indwelling needle by inserting the external conduit into a connecting hole provided in a needle hub and fixing it to the inner surface of the connecting hole by means of adhesion, welding, or the like.

[0136] However, after detailed investigation by the inventors, it was found that, for example, when the external conduit was significantly deformed, the external conduit could bend excessively at the open end of the connection hole, resulting in damage, or the external conduit could come loose from the connection hole.

[0137] The problem to be solved by Invention B is to provide a novel puncture needle body that can suppress deformation of the external duct and prevent damage to or removal of the external duct.

[0138] Another object of Invention B is to provide a needle assembly including the above-mentioned puncture needle body.

[0139] Below, we will describe preferred embodiments for understanding Invention B. However, the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may also be recognized and employed independently to the extent possible, and may also be appropriately combined with any of the components described in other embodiments. Therefore, Invention B is not limited to the embodiments described below, and various other embodiments may be realized.

[0140] The first aspect of Invention B is a puncture needle body having a needle hub provided at the base end of the puncture needle, in which a connection hole is formed at the base end of the needle hub, and a connection port into which an external conduit is externally attached protrudes from the wall of the connection hole toward the base end of the needle hub.

[0141] According to the puncture needle body of this aspect, the external conduit is inserted into the connection hole and is attached to the outside of the connection port, so that the external conduit is unlikely to separate from the connection port.

[0142] A second aspect of Invention B is the puncture needle body according to the first aspect of Invention B, wherein the connection port is located more inward than the open end of the connection hole.

[0143] With this type of puncture needle body, the external conduit attached in an extrapolated state to the connection port abuts against the inner surface of the connection hole outside the protruding tip of the connection port, thereby limiting the amount of deformation, and preventing the external conduit from being damaged by excessive bending, etc.

[0144] The third aspect of Invention B is a puncture needle body according to the first or second aspect of Invention B, wherein the inner dimensions of the connection hole on the base end side are larger than the inner dimensions on the tip end side.

[0145] According to the puncture needle of this aspect, the operation of inserting the external conduit into the connecting hole becomes easy.

[0146] The fourth aspect of Invention B is a puncture needle body according to the third aspect of Invention B, wherein the connection hole has a tapered shape that increases in diameter toward the base end of the needle hub.

[0147] According to the puncture needle body of this aspect, the area of ​​the inner peripheral surface of the connection hole can be made large, and therefore, when an external conduit is bonded to the inner peripheral surface of the connection hole, the bonding area becomes large and the bonding strength can be increased. Note that this aspect includes not only cases where the entire connection hole is tapered so that the diameter increases toward the open end, but also cases where the connection hole is tapered in the axial direction partially toward the open end.

[0148] A fifth aspect of Invention B is a puncture needle body according to any one of the first to fourth aspects of Invention B, wherein the cross section of the opening edge of the connection hole has a curved shape.

[0149] According to the puncture needle body of this aspect, when inserting the external conduit into the connection hole, the opening edge of the connection hole, which has a curved cross-sectional shape, functions as a guide to guide the external conduit into the connection hole, making it easier to insert the external conduit into the connection hole. Furthermore, for example, if the cross section of the opening edge of the connection hole has a curved shape that is convex toward the inner circumference of the connection hole, the opening edge of the connection hole can be made smooth, thereby preventing damage to the external conduit due to contact with the opening edge of the connection hole when the external conduit connected to the connection port deforms and comes into contact with the opening edge of the connection hole.

[0150] A sixth aspect of Invention B is a puncture needle body according to any one of the first to fifth aspects of Invention B, wherein the connection port has a tapered outer circumferential surface.

[0151] The puncture needle body of this aspect facilitates the extrapolation of the external conduit to the connection port. When the outer circumferential surface of the connection port is fixed to the external conduit, a large fixing area between the connection port and the external conduit can be ensured, thereby improving the fixing strength. Note that this aspect includes not only cases where the entire outer circumferential surface of the connection port is tapered, but also cases where the outer circumferential surface of the connection port has a tapered outer circumferential surface partially in the axial direction.

[0152] The seventh aspect of Invention B is a puncture needle body described in any one of the first to sixth aspects of Invention B, wherein the cross section of the outer peripheral edge of the tip of the connection port is rounded and has no corners.

[0153] According to this embodiment of the puncture needle body, the cross section of the outer peripheral edge of the tip of the connection port has an R-shape without any corners, so that even if the external conduit is bent, the connection port can be prevented from breaking through the external conduit.

[0154] The eighth aspect of Invention B is a needle assembly comprising a puncture needle body described in any one of the first to seventh aspects of Invention B and a needle tip protector that covers the tip of the puncture needle by moving in the needle axial direction relative to the puncture needle body, wherein a pair of arms that engage with the needle tip protector are provided on the base end side of the needle hub, and the minimum thickness dimension of the arms in an axial longitudinal section parallel to the opposing direction of the pair of arms is set to be larger than the minimum thickness dimension of the peripheral wall of the connection hole.

[0155] According to the needle assembly of this aspect, it is possible to ensure the strength of the arm portion, which is subject to deformation due to the action of an external force when the needle hub and the needle tip protector are separated.

[0156] A ninth aspect of Invention B is the needle assembly according to the eighth aspect of Invention B, wherein a reinforcing part that is thicker than the peripheral wall of the connection hole is provided closer to the tip than the connection hole.

[0157] For example, when an external conduit is glued to a needle hub, the adhesion of the plasticizer in the adhesive can cause cracks on the distal side of the connection hole, potentially damaging the needle hub. According to this needle assembly, a thick reinforcement is provided in the area at risk of damage, preventing poor adhesion of the external conduit due to damage to the needle hub.

[0158] According to Invention B, in the puncture needle body, deformation of the outer duct can be suppressed, and damage to or removal of the outer duct can be prevented.

[0159] Hereinafter, an embodiment of the invention B will be described with reference to the drawings.

[0160] 15 to 18 show a needle assembly B-12 equipped with a puncture needle B-10 as a first embodiment of Invention B. The needle assembly B-12 has a structure in which the puncture needle B-10 is inserted into a needle tip protector B-14 so as to be movable in the needle axial direction. In the following description, unless otherwise specified, the distal end side refers to the left side in FIG. 15, which is the side of the needle tip B-20 (described later) of the puncture needle B-10, and the proximal end side refers to the right side in FIG. 15, which is the rear side in the puncture direction of the puncture needle B-10. Furthermore, as a general rule, the up-down direction refers to the vertical direction in FIG. 16, which is the vertical direction, and the left-right direction refers to the horizontal direction in FIG. 26. For ease of viewing, in FIGS. 15 to 20 relating to Invention B, the "B-" has been omitted from each reference numeral "B-○○" (○○ is a number corresponding to the part). In addition, to make it easier to understand that FIGS. 15 to 20 are drawings relating to Invention B, [Invention B] is written in FIGS.

[0161] More specifically, the puncture needle body B-10 comprises a puncture needle B-16 and a needle hub B-18 provided at the base end of the puncture needle B-16. The puncture needle B-16 is formed of a metal such as stainless steel, and has a sharp, tapered tip B-20 at one end. A through-hole B-22 is formed at the tip of the puncture needle B-16, allowing blood to easily flow into the lumen of the puncture needle B-16.

[0162] The needle hub B-18 has a generally cylindrical shape overall, and the base end portion of the puncture needle B-16 is inserted and fixed in its tip portion. This allows the inner cavity of the needle hub B-18 to communicate with the inner cavity of the puncture needle B-16 in the needle axial direction. The needle hub B-18 has a needle support part B-24 that forms the tip portion and a protector connecting part B-26 that forms the base portion.

[0163] The needle support part B-24 has a substantially cylindrical shape and is made of, for example, a hard synthetic resin. The inner diameter of the tip of the needle support part B-24 is substantially the same as the outer diameter of the puncture needle B-16, and the base end of the puncture needle B-16 is inserted and fixed through an opening on the tip side of the needle support part B-24. The puncture needle B-16 and the needle support part B-24 may be bonded together, if necessary.

[0164] The outer peripheral surface of the intermediate portion in the needle axial direction of the needle support portion B-24 is a tapered surface B-30 whose diameter gradually increases toward the tip. As a result, the intermediate portion in the needle axial direction of the needle support portion B-24 having the tapered surface B-30 is a small-diameter cylindrical portion B-32 whose diameter is smaller than the tip and base end portions. The outer peripheral surface of the needle support portion B-24 is not limited to the tapered surface B-30 whose outer dimensions change in the axial direction, and may have approximately constant outer dimensions in the axial direction except for the recessed portion B-34 and the protruding portion B-36 described below.

[0165] A recess B-34 that opens onto the outer peripheral surface is formed in the needle support portion B-24 at a portion distal to the tapered surface B-30. The recess B-34 is annular and has a substantially constant cross-sectional shape all around. The minimum outer diameter of the needle support portion B-24 at the location where the recess B-34 is formed is substantially the same as the minimum outer diameter of the base end of the small-diameter cylindrical portion B-32.

[0166] An annular protrusion B-36 protrudes from the outer peripheral surface of the needle support B-24, closer to the tip than the recess B-34. The protrusion B-36 is provided at or near the tip of the needle support B-24, and in this embodiment constitutes the tip of the needle support B-24. The outer diameter of the needle support B-24 at the portion where the protrusion B-36 is formed is larger than the outer diameter of the tip, which is the maximum outer diameter of the small-diameter cylindrical portion B-32.

[0167] The base-end side surface constituting the inner surface of the recess B-34 is an annular base-end restriction surface B-38 extending in the axis-perpendicular direction, and the bottom surface of the recess B-34 and the tapered surface B-30 are connected in a stepped manner via the base-end restriction surface B-38. The tip-end side surface constituting the inner surface of the recess B-34 is an annular tip-end restriction surface B-40 extending in the axis-perpendicular direction, and the bottom surface of the recess B-34 and the outer peripheral surface of the protrusion B-36 are connected in a stepped manner via the tip-end restriction surface B-40. The axis-perpendicular dimension of the base-end restriction surface B-38 formed by the base-end inner surface of the recess B-34 is slightly larger than the axis-perpendicular dimension of the tip-end restriction surface B-40.

[0168] The protector connecting portion B-26 is formed of, for example, a hard synthetic resin, similar to the needle support portion B-24. The protector connecting portion B-26 has a stepped, generally cylindrical shape, with a small-diameter connecting tube portion B-42 at its distal end and a large-diameter connecting tube portion B-44 at its proximal end. The protector connecting portion B-26 is fixed to the needle support portion B-24 by inserting the proximal end of the needle support portion B-24 into the connecting tube portion B-42 and, if necessary, by gluing or welding. A generally rectangular recess B-46 is formed in the longitudinal surface (the up-down direction in FIG. 16 ) of the protector connecting portion B-26. In this embodiment, the recess B-46 is provided on the surface of the connecting tube portion B-42 as shown in FIG. 15 , but it may also be provided on the surface of the connecting tube portion B-44, or it may be provided across the connecting tube portion B-42 and the connecting tube portion B-44. The needle support portion B-24 and the protector connecting portion B-26 may be integrally formed.

[0169] As shown in Figures 17 and 18, the connecting tubular portion B-44 of the needle hub B-18 has a connecting hole B-48. The connecting hole B-48 has a substantially circular cross section. The connecting hole B-48 has a bottom portion B-50 on the tip side, opposite the opening. The inner hole of the connecting tubular portion B-44 passes axially through the bottom portion B-50, and the bottom portion B-50 is annular. The connecting hole B-48 has a larger diameter at the base end, which is the opening side, than at the tip side, which is the bottom portion B-50 side. The connecting hole B-48 gradually becomes larger in diameter toward the opening end, which is the base end, and the inner surface of the peripheral wall of the connecting hole B-48 is tapered cylindrical. The opening edge of the connecting hole B-48 has an opening expansion portion B-52, whose cross section has a curved cross section in which the inclination angle of the inner surface of the peripheral wall is partially increased.

[0170] A reinforcing portion B-54 is provided further forward than the connection hole B-48, and is thicker in the axially perpendicular direction than the peripheral wall of the connection hole B-48. In this embodiment, the reinforcing portion B-54 is configured to include the bottom B-50 of the connection hole B-48. The reinforcing portion B-54 is thicker than the opening expansion portion B-52. The inner and outer peripheral surfaces of the reinforcing portion B-54 are continuous with the outer peripheral surface of the peripheral wall of the connection hole B-48 and the inner peripheral surface of the connection port B-56 ​​described below. However, for example, the reinforcing portion B-54 can be made thicker by providing a protrusion that protrudes toward at least one of the outer and inner circumferences.

[0171] A connection port B-56 ​​protrudes from the bottom B-50 of the connection hole B-48. The connection port B-56 ​​is cylindrical. The connection port B-56 ​​is provided on the inner circumferential side of the peripheral wall of the connection hole B-48. The connection port B-56 ​​protrudes from the bottom B-50, which constitutes the wall of the connection hole B-48, toward the base end toward the opening of the connection hole B-48, thereby enabling the connection portion of the external conduit B-60 in the needle hub B-18 to have a relatively small diameter. The inner circumferential surface of the connection port B-56 ​​is a cylindrical surface having a substantially constant diameter in the axial direction. The outer circumferential surface of the connection port B-56 ​​has a diameter that gradually decreases toward the base end in the axial direction, forming a tapered outer circumferential surface B-58. As shown enlarged in Figure 17, the connection port B-56 ​​has a rounded cross section at the tip outer circumferential edge. The connection port B-56 ​​may be separate from the connection cylindrical portion B-44, but in this embodiment it is formed integrally with the connection cylindrical portion B-44.

[0172] The protector connecting portion B-26 is attached by inserting the tip of the external conduit B-60 into the connecting hole B-48 of the connecting tubular portion B-44, and the tip of the external conduit B-60 being fitted onto the connecting port B-56. The external conduit B-60 is attached to the inner circumferential surface of the connecting hole B-48 and the connecting port B-56 ​​by adhesive or welding as necessary. By connecting the external conduit B-60 to the connecting tubular portion B-44, the needle support portion B-24 and the external conduit B-60 are connected to both sides of the protector connecting portion B-26, and the lumen of the puncture needle B-16 and the lumen of the needle hub B-18 are connected to the external conduit B-60. As a result, a fluid flow path B-62 is provided in the puncture needle body B-10, extending from the tip opening of the puncture needle B-16 to the external conduit B-60.

[0173] The tip of the external conduit B-60 is not only inserted into the connection hole B-48 but also extrapolated to the connection port B-56, thereby more firmly connecting the external conduit B-60 to the needle hub B-18 and preventing the external conduit B-60 from coming off the needle hub B-18.

[0174] The tapered inner peripheral surface of the connection hole B-48 ensures a large bonding area when the outer peripheral surface of the external conduit B-60 is fixed to the inner peripheral surface of the connection hole B-48. Similarly, the tapered outer peripheral surface of the connection port B-56 ​​ensures a large bonding area when the inner peripheral surface of the external conduit B-60 is fixed to the outer peripheral surface of the connection port B-56. These factors make it possible to achieve a high bonding strength of the external conduit B-60 to the needle hub B-18.

[0175] The connecting tubular portion B-44 is provided with a pair of arms B-64, 64 extending toward the tip. The arms B-64, 64 are arranged opposite each other in the radial direction and extend around the outer periphery of the connecting tubular portion B-42 further toward the tip than the connecting tubular portion B-42. The arms B-64, 64 are arranged spaced apart from the outer periphery of the connecting tubular portion B-42, and the connecting portion with the connecting tubular portion B-44 is thin-walled and narrow, allowing elastic deformation in the direction of approaching each other when subjected to an external force.

[0176] A hook B-66 is formed at the tip of each of the arms B-64, 64. The hook B-66 protrudes outward from each arm B-64 in the opposing direction of the arms B-64, 64. The pair of hooks B-66, 66 move in directions approaching each other as the arms B-64, 64 elastically deform in the approaching direction.

[0177] As shown in Figures 15 to 18, the needle tip protector B-14 has a generally cylindrical shape extending in the needle axis direction as a whole, and is integrally molded from a hard synthetic resin such as polypropylene, polycarbonate, glycol-modified polyethylene terephthalate, ABS resin, or MBS resin. The needle tip protector B-14 is preferably transparent or translucent to allow visible light to pass through. The needle tip protector B-14 has a cylindrical peripheral wall B-68, and an inner hole B-70 that penetrates the inner periphery of the peripheral wall B-68 in the needle axis direction is formed.

[0178] The peripheral wall B-68 has a cylindrical portion B-72 as a distal end tubular portion having a substantially circular cross section at its distal end, and an expanded portion B-74 as a large-diameter tubular portion having a larger diameter than the cylindrical portion B-72 at its proximal end. The expanded portion B-74 has a different shape in the needle axial direction.

[0179] The expansion section B-74 has a generally elliptical cylindrical shape, and the width dimension of the outer peripheral surface in the horizontal direction (the larger diameter direction) is larger than the width dimension of the outer peripheral surface in the vertical direction (the smaller diameter direction). Of the wall portions constituting the expansion section B-74, the portions constituting the vertical wall portion are narrow width portions B-76, 76, while the portions constituting the horizontal wall portion are wide width portions B-78, 78, which have dimensions larger than those of the narrow width portions B-76, 76. The opposing directions of the narrow width portions B-76, 76 and the opposing directions of the wide width portions B-78, 78 are generally perpendicular to each other. The narrow width portions B-76, 76 and the wide width portions B-78, 78 may have the same dimensions.

[0180] The outer diameter of the outer peripheral surface of the widened portions B-78, 78 gradually increases from the distal end toward the proximal end. The outer peripheral surface of the cylindrical portion B-72 and the outer peripheral surfaces of the widened portions B-78, 78 are smoothly connected. The wall thickness from the cylindrical portion B-72 to the widened portions B-78, 78 is approximately constant in the needle axial direction. The widened portions B-78, 78 have a substantially elliptical cross section in which the outer peripheral surface and the inner peripheral surface correspond to each other, and the thickness is approximately constant in the circumferential direction. An internal space B-80 having a flat cross section with a larger horizontal dimension than a vertical dimension is formed on the inner periphery of the expanded portion B-74 at the proximal end of the inner hole B-70 that penetrates the needle tip protector B-14. The internal horizontal dimension of the internal space B-80 gradually increases toward the proximal end.

[0181] The wide portions B-78, 78 are formed with through-windows B-82, 82 as engagement portions that penetrate in the plate thickness direction. The circumferential dimension of the through-windows B-82, 82 is larger than the circumferential dimension of the hooks B-66, 66. In this embodiment, when molding the needle tip protector B-14, the mold for molding the outer peripheral surface is split in the vertical direction, so the through-windows B-82, 82 are shaped so that no undercut occurs when the mold is removed in the vertical direction.

[0182] An annular stepped surface B-84 that expands in the axis-perpendicular direction is formed on the inner peripheral surface of the peripheral wall B-68 at the front end of the expanding portion B-74 (see FIG. 19). The inner peripheral surface of the peripheral wall B-68 has a larger diameter on the distal side of the stepped surface B-84 than on the proximal side. The dimension of the stepped surface B-84 in the axis-perpendicular direction is smaller than the dimension of the distal restriction surface B-40 of the recess B-34 in the axis-perpendicular direction.

[0183] The peripheral wall B-68 is also provided with a pair of protrusions B-86, 86 that protrude from the inner peripheral surface of the expanded portion B-74 into the internal space B-80. As shown in FIG. 17, the protrusions B-86, 86 are integrally formed with the wide portions B-78, 78 of the expanded portion B-74 of the peripheral wall B-68. The protrusions B-86, 86 are disposed on the inner peripheral side of the wide portions B-78, 78 at positions corresponding to the wide portions B-78, 78. The protrusions B-86, 86 are disposed opposite each other in the lateral direction and are spaced apart from each other in the circumferential direction. The protrusions B-86, 86 protrude toward the base end of the peripheral wall B-68 on the base end side of the stepped surface B-84. The protrusions B-86, 86 extend from the stepped surface B-84 toward the base end side substantially parallel to the needle axial direction, and at least the protruding tip portions are arranged spaced apart from the wide portions B-78, 78 of the peripheral wall B-68 toward the inner circumferential side. The protrusions B-86, 86 are each curved in the circumferential direction. The protrusions B-86 may be arranged so as not to come into contact with the outer circumferential surface of the needle support portion B-24 other than the recessed portion B-34 and the protruding portion B-36. The widened portion B-74 may have a notch, and the protrusions B-86, 86 may be arranged at a distance from the notch.

[0184] A pair of claws B-88, 88 are formed at the protruding tips (proximal ends in the needle axis direction) of the projections B-86, 86, bending and protruding inward. The inner peripheral surfaces of the claws B-88, 88 are each curved in the circumferential direction, and the radius of curvature of the inner peripheral surfaces at the protruding tips of the claws B-88, 88 is approximately equal to the radius of curvature of the outer peripheral surface of the small-diameter cylindrical portion B-32 of the needle support portion B-24. The radial distance between opposing surfaces at the protruding tips of the claws B-88, 88 is approximately equal to the outer diameter of the small-diameter cylindrical portion B-32, but is smaller than the maximum outer diameter of the tip portion of the tapered surface B-30. However, the radial distance between opposing surfaces at the protruding tips of the claws B-88, 88 may be slightly smaller or larger than the outer diameter of the small-diameter cylindrical portion B-32. Furthermore, when the outer surface of the needle support portion B-24 other than the convex portion B-36 and the concave portion B-34 has a constant diameter, the radial distance between the opposing surfaces at the protruding tips of the claw portions B-88, 88 may be slightly smaller than the outer diameter dimension of the outer surface, slightly larger than the outer diameter dimension of the outer surface, or may be approximately the same.

[0185] The proximal end surfaces B-90, 90 of the claws B-88, 88 have an inner circumferential portion formed as a vertical surface B-90a, 90a extending in the axis-perpendicular direction, and an outer circumferential portion formed as an inclined surface B-90b, 90b sloping toward the distal end in the needle axis direction (see FIG. 19). In this embodiment, the axis-perpendicular dimension of the vertical surface B-90a, 90a is approximately the same as or slightly larger than the axis-perpendicular dimension of the proximal restriction surface B-38 of the recess B-34. As a result, when the claws B-88, 88 abut against the proximal restriction surface B-38 as described below, the entire surface of the proximal restriction surface B-38 abuts against the vertical surface B-90a, 90a, ensuring a sufficiently large contact area. Furthermore, the inclined surfaces B-90b, 90b located on the outer periphery of the vertical surfaces B-90a, 90a are inclined toward the tip side in the needle axial direction as they approach the outer periphery, so that the vertical surfaces B-90a, 90a and the base end regulating surface B-38 abut without interference from the inclined surfaces B-90b, 90b.

[0186] In addition, the protruding tips (base ends in the needle axial direction) of the claws B-88, 88 are located further to the tip side in the needle axial direction than the base end of the expanding portion B-74. Therefore, the entire projecting pieces B-86, 86 are accommodated in the internal space B-80 of the expanding portion B-74.

[0187] As shown in Figure 15, a wing-like portion B-92 is provided at the tip portion of the needle tip protector B-14. The wing-like portion B-92 is made of, for example, a soft synthetic resin. The wing-like portion B-92 has plate-like connecting portions B-96, 96 integrally formed with a cylindrical fitting portion B-94, which protrude in the tangential direction of the fitting portion B-94, and a wing main body B-98 is integrally formed at each of the connecting portions B-96, 96 on the tip side protruding from the fitting portion B-94. The wing-like portion B-92 is attached to the peripheral wall B-68 of the needle tip protector B-14 by externally fitting the fitting portion B-94 onto the tip portion of the cylindrical portion B-72.

[0188] The puncture needle body B-10 is inserted through the inner hole B-70 of the needle tip protector B-14 from the opening on the proximal end side, and the needle tip protector B-14 is fitted onto the puncture needle body B-10 to form the needle assembly B-12. In the initial state before use of the needle assembly B-12 shown in Figure 15, the needle tip B-20 of the puncture needle body B-10 is located further distal than the needle tip protector B-14, and the needle tip B-20 is exposed. In this initial state, as shown in Figure 17, the hooks B-66, 66 provided on the needle hub B-18 of the puncture needle body B-10 are inserted into and engaged with the through windows B-82, 82 provided in the expanded portion B-74 of the needle tip protector B-14. This connects the needle tip protector B-14 and the needle hub B-18, maintaining the needle tip B-20 in a protruding state, and restricts movement of the puncture needle B-16 toward the base end in the needle axial direction due to resistance during puncture, for example, when holding the wing-shaped portion B-92 and performing a puncture.

[0189] In the initial state of the needle assembly B-12, the claws B-88, 88 of the needle tip protector B-14 abut against the outer peripheral surface of the small-diameter cylindrical portion B-32 of the needle support portion B-24. Note that these claws B-88, 88 may be slightly pressed outward by abutting against the outer peripheral surface of the small-diameter cylindrical portion B-32, or may be slightly spaced apart from the outer peripheral surface of the small-diameter cylindrical portion B-32.

[0190] The needle assembly B-12 is used for transfusion, blood collection, hemodialysis, etc. through the fluid flow path B-62 by inserting the puncture needle B-16 into a patient's blood vessel and leaving the puncture needle body B-10 as an indwelling needle. Note that, since the needle assembly B-12 of this embodiment is provided with winged portions B-92, it is possible to insert the puncture needle B-16 of the puncture needle body B-10 while pinching the winged portions B-92, for example. When leaving the puncture needle body B-10 in the inserted state, it can be fixed with tape at the position of the winged portions B-92, allowing it to be fixed with a wide contact area with the skin.

[0191] When removing the puncture needle body B-10, the arms B-64, 64 of the needle hub B-18 are pressed inward with the fingers while the needle tip protector B-14 remains fixed with tape to the wing-like portion B-92. This releases the engagement between the hooks B-66, 66 and the through windows B-82, 82, allowing the puncture needle body B-10 to be moved proximally relative to the needle tip protector B-14. By moving the puncture needle body B-10 proximally relative to the needle tip protector B-14 and removing the puncture needle B-16 from the skin, the needle tip protector B-14 moves toward the needle tip B-20 relative to the puncture needle body B-10.

[0192] When the hooks B-66, 66 and the through windows B-82, 82 are released, the puncture needle body B-10 will not move toward the base end relative to the needle tip protector B-14 unless an external force is applied to the puncture needle body B-10 to move it toward the base end relative to the needle tip protector B-14. That is, the claws B-88, 88 abut against the tapered surface B-30, which becomes larger in diameter toward the tip end, preventing the puncture needle body B-10 from moving toward the base end relative to the needle tip protector B-14. This prevents the needle tip B-20 of the puncture needle body B-10 from being unintentionally protected by the needle tip protector B-14.

[0193] By moving the puncture needle body B-10 toward the base end relative to the needle tip protector B-14, the claws B-88, 88 slide against the tapered surface B-30, and the elastic restoring force of the protrusions B-86, 86 acts as a biasing force pressing the claws B-88, 88 against the tapered surface B-30. Therefore, the user can move the puncture needle body B-10 while feeling the resistance caused by the contact between the claws B-88, 88 and the tapered surface B-30, confirming the feeling that the puncture needle body B-10 is being pulled out of the needle tip protector B-14.

[0194] As shown in Fig. 19, by moving the puncture needle body B-10 backward to a predetermined position relative to the needle tip protector B-14 (moving the needle tip protector B-14 forward toward the needle tip B-20 of the puncture needle body B-10), the needle tip B-20 of the puncture needle B-16 is covered by the needle tip protector B-14. Furthermore, the claws B-88, 88 provided on the free ends of the protruding pieces B-86, 86 move over the opening of the recess B-34, and the claws B-88, 88, which have elastically restored their shape, enter the recess B-34. As a result, the vertical surfaces B-90a, 90a of the claws B-88, 88 abut and engage with the base-end restriction surface B-38 of the recess B-34. Then, the movement of the puncture needle body B-10 toward the tip side relative to the needle tip protector B-14 is restricted, and the needle tip B-20 of the puncture needle body B-10 is prevented from being exposed again.

[0195] The stepped surface B-84 provided at the front end portion of the protrusions B-86, 86 and the tip-side restricting surface B-40 of the recess B-34 come into contact and engage, thereby restricting the movement of the puncture needle B-10 toward the base end. This prevents the puncture needle B-10 from being pulled out toward the base end relative to the needle tip protector B-14. Therefore, movement of the puncture needle B-10 in both axial directions relative to the needle tip protector B-14 is prevented, and the protection of the needle tip B-20 by the needle tip protector B-14 is maintained.

[0196] In this embodiment, a pair of protrusions B-86, 86 are provided, and together with the protrusions B-86, 86 being integrally molded with the peripheral wall B-68 of the needle tip protector B-14, problems such as rattling of the needle tip protector B-14 relative to the puncture needle body B-10 can be effectively prevented when the claws B-88, 88 and the base-end regulating surface B-38 are engaged. Thus, by providing two or more protrusions B-86, the needle tip protector B-14 is more reliably prevented from retracting toward the base end relative to the puncture needle body B-10, and the effect of preventing re-exposure of the needle tip B-20 can be more stably achieved. In this case, it is preferable that the multiple protrusions B-86 be arranged approximately symmetrically with respect to the central axis of the needle tip protector B-14.

[0197] With the needle tip B-20 of the puncture needle body B-10 protected by the needle tip protector B-14, the tape fixing of the winged portion B-92 is released and the needle assembly B-12 is removed from the patient. However, the procedure for protecting the needle tip B-20 is not limited to the above procedure. Specifically, for example, the tape fixing of the winged portion B-92 may be released, the entire needle assembly B-12 is moved back to remove the puncture needle B-16 from the blood vessel, and then the puncture needle body B-10 may be moved back relative to the needle tip protector B-14 to protect the needle tip B-20 of the puncture needle B-16.

[0198] When the claws B-88, 88 enter the recess B-34, the tips of the claws B-88, 88 come into contact with the bottom surface of the recess B-34, allowing the user to hear the impact and sound of the contact. This avoids the possibility that the user will interrupt the operation of pulling out the puncture needle body B-10 midway, and the protection of the needle tip B-20 by the needle tip protector B-14 can be more reliably achieved.

[0199] In the needle tip protector B-14 and needle assembly B-12 constructed as described above, the entire protrusions B-86, 86 that prevent the re-exposure of the needle tip B-20 of the puncture needle body B-10 are housed within the cylindrical peripheral wall B-68. This makes it virtually impossible to unintentionally contact the protrusions B-86, 86 from the outside. Therefore, when the needle tip B-20 of the puncture needle body B-10 is protected by the needle tip protector B-14, it is possible to effectively prevent the needle tip B-20 from being re-exposed from the needle tip protector B-14 by unintentionally releasing the engagement between the protrusions B-86, 86 and the recess B-34.

[0200] When the protrusions B-86, 86 are engaged with the needle hub B-18, for example, if an external force in a bending direction is applied to the needle tip protector B-14 and / or the needle hub B-18, the protrusions B-86, 86 can come into contact with the wide portions B-78, 78 located away from the outer periphery. This limits the deformation of the protrusions B-86, 86 toward the outer periphery, reducing the risk of the protrusions B-86, 86 being disengaged from the needle hub B-18, and therefore the protection state of the needle tip B-20 of the puncture needle body B-10 can be stably maintained.

[0201] The protrusions B-86, 86 are provided on an expanded portion B-74 expanded at the base end side of the needle tip protector B-14. This allows the size of the protrusions B-86, 86 to be sufficiently ensured, while also allowing the outer diameter dimension of the needle support portion B-24 of the needle hub B-18, which is inserted between the protrusions B-86, 86, to be sufficiently large. Furthermore, in this embodiment, the expanded portion B-74 is made substantially elliptical, and its outer peripheral surface is smoothly continuous with the outer peripheral surface of the cylindrical portion B-72, thereby reducing the risk of the expanded portion B-74 or the like coming into contact with the patient and causing pain to the patient.

[0202] Since the protrusions B-86, 86 are provided inside the wide portions B-78, 78 that constitute the expansion portion B-74, the wide portions B-78, 78 are prevented from becoming thick, thereby suppressing the occurrence of dimensional errors and deterioration in quality due to the incorporation of air bubbles into the member during molding, the occurrence of sink marks and voids, etc. Furthermore, it is preferable that the locking portions (protrusions B-86, 86) are provided so as to extend in the same direction (toward the base end in the axial direction) as the wide portions B-78, 78. This prevents the expansion portion B-74 from becoming larger than necessary, makes it possible to effectively utilize the space inside the wide portions B-78, 78, and prevents the wide portions B-78, 78 from becoming thick.

[0203] Since the protruding pieces B-86, 86 extend toward the base end side, they do not get caught when the puncture needle body B-10 is pulled out from the needle tip protector B-14, and smooth pulling out can be achieved.

[0204] The mutually engaging vertical surfaces B-90a, 90a of the claws B-88, 88 and the proximal-end regulating surface B-38 of the recess B-34 both extend in the axially perpendicular direction. Furthermore, the mutually engaging stepped surface B-84 and the distal-end regulating surface B-40 of the recess B-34 both extend in the axially perpendicular direction. Therefore, the needle tip protector B-14, which includes the vertical surfaces B-90a, 90a and the stepped surface B-84, and the needle hub B-18, which includes the proximal-end regulating surface B-38 and the distal-end regulating surface B-40, are free from undercuts and easy to mold. Moreover, the abutment force and abutment reaction force due to the abutment between the vertical surfaces B-90a, 90a and the proximal-end regulating surface B-38 act without tilting relative to the axial direction. Similarly, the contact force and contact reaction force due to the contact between the stepped surface B-84 and the distal end side restriction surface B-40 act without tilting in the axial direction. Furthermore, the contact area of ​​each can be sufficiently secured, so that the needle tip protector B-14 can be more reliably prevented from moving toward the distal end and the proximal end relative to the puncture needle body B-10.

[0205] Since the connection port B-56 ​​is located closer to the bottom B-50 than the open end face of the connection hole B-48 and is arranged in a housed state in the connection hole B-48, when the tip of the external conduit B-60 connected to the needle hub B-18 bends from the tip of the connection port B-56, the amount of deformation of the external conduit B-60 is limited by its contact with the inner peripheral wall of the connection hole B-48. Therefore, damage due to excessive deformation of the external conduit B-60 is avoided, and the durability of the external conduit B-60 is improved.

[0206] Because the cross section of the tip outer peripheral edge of the connection port B-56 ​​is rounded and has no corners, even if the inner surface of the external conduit B-60 is pressed against the tip outer peripheral edge of the connection port B-56, damage to the external conduit B-60 is unlikely to occur.

[0207] By providing the connection port B-56 ​​in a state where it is housed in the connection hole B-48, it is possible to prevent the connection port B-56, before the external conduit B-60 is attached, from interfering with and getting caught on other components, etc. Furthermore, since the connection port B-56 ​​is protected from the outside by the peripheral wall of the connection hole B-48, the connection port B-56 ​​is less likely to be damaged.

[0208] The inner peripheral surface of the connection hole B-48 is tapered, and the diameter of the connection hole B-48 increases toward the open end, making it easy to insert the external conduit B-60 into the connection hole B-48. In particular, the outer peripheral surface of the connection port B-56 ​​is tapered to a point B-58, which increases the gap between the inner peripheral surface of the connection hole B-48 and the outer peripheral surface of the connection port B-56 ​​on the opening side of the connection hole B-48, making it easy to insert the external conduit B-60 between the connection hole B-48 and the connection port B-56.

[0209] Furthermore, since an opening expansion portion B-52 having a large diameter and a curved cross-sectional shape is provided at the opening portion of the connection hole B-48, when the external conduit B-60 is inserted into the connection hole B-48, the tip of the external conduit B-60 abuts against the opening expansion portion B-52 and is guided, making it easier to insert the external conduit B-60 into the connection hole B-48.

[0210] The opening of the connection hole B-48 is provided with the opening expansion portion B-52 having a larger diameter, so that deformation of the external conduit B-60 is permitted to a certain extent without contacting the opening of the connection hole B-48, thereby preventing the external conduit B-60 from being excessively pressed against the peripheral wall of the connection hole B-48. Furthermore, when the external conduit B-60 abuts against the opening expansion portion B-52, the opening expansion portion B-52 has a curved cross-sectional shape, so that stress concentration due to abutment against the opening expansion portion B-52 is unlikely to occur in the external conduit B-60.

[0211] A thick reinforcing portion B-54 is provided closer to the tip than the connecting hole B-48, and the portion of the needle hub B-18 that is likely to be damaged by the plasticizer in the adhesive when the external conduit B-60 is adhered to the needle hub B-18 is made into the reinforcing portion B-54. This prevents damage to the needle hub B-18 and avoids poor adhesion between the external conduit B-60 and the needle hub B-18.

[0212] Figure 20 shows a puncture needle body B-100 as a second embodiment of invention B. The puncture needle body B-100 has a structure in which the base end of a puncture needle B-16 is supported by a needle hub B-102. In the following explanation, the same members and parts as those in the first embodiment of invention B are denoted by the same reference numerals in the drawings and explanations thereof will be omitted.

[0213] The needle hub B-102 has a tip portion that is a small-diameter cylindrical needle support portion B-103 and a base portion that is a protector connecting portion B-104 that has a larger diameter than the needle support portion B-103. The protector connecting portion B-104 is formed integrally with the needle support portion B-103 and has a connecting hole B-106 that opens into the base end surface.

[0214] The connection hole B-106 is a circular hole with a bottom, and the inner hole of the needle hub B-102 passes through the center of the bottom B-108 in the axial direction. The inner surface of the peripheral wall of the connection hole B-106 is tapered, with the portion closer to the bottom B-108 gradually increasing in diameter toward the opening, and the portion closer to the opening is a cylindrical surface extending in the axial direction with a substantially constant diameter. In this way, the connection hole does not necessarily have to be tapered as a whole, and may have a tapered portion in part. The opening edge of the connection hole B-106 is an opening expansion portion B-110 whose cross section is curved without any corners.

[0215] A reinforcing part B-112 is provided on the protector connecting part B-104 closer to the tip than the connecting hole B-106. The reinforcing part B-112 has a radial thickness dimension greater than that of the peripheral wall of the connecting hole B-106. The reinforcing part B-112 is configured to include the bottom part B-108 of the connecting hole B-106. The end part on the tip side (needle support part B-103 side) of the reinforcing part B-112 is tapered so that the diameter gradually decreases toward the tip side.

[0216] A connection port B-114 is provided at the bottom B-108 of the connection hole B-106, protruding axially toward the opening of the connection hole B-106. The connection port B-114 is located closer to the bottom B-108 than the opening end face of the connection hole B-106, and is provided in a state of being housed in the connection hole B-106.

[0217] A pair of arms B-116, 116 are integrally formed on the peripheral wall of the connection hole B-106. The arms B-116, 116 are arranged opposite each other in the axis-perpendicular direction, are disposed outside the protector connecting part B-104, and are integrally connected at their base ends to the base end of the protector connecting part B-104. The arms B-116, 116 are arranged apart from the protector connecting part B-104, and the connection part with the protector connecting part B-104 is thin-walled, allowing elastic deformation in the axis-perpendicular direction in which they approach each other when subjected to external force.

[0218] In Figure 20, which shows an axial cross section parallel to the opposing direction of the pair of arms B-116, 116, the minimum thickness dimension T of the pair of arms B-116, 116 is set to be larger than the minimum thickness dimension t of the peripheral wall of the connection hole B-106. This ensures sufficient strength for the arms B-116, 116, which are deformed by an external force when the needle hub B-102 and a needle tip protector (not shown) are separated. Furthermore, when an external force acts on the arms B-116, 116, stress is dispersed as necessary to portions of the connection hole B-106 that are thinner than the minimum thickness of the arms B-116, 116, thereby easing stress concentration on the arms B-116, 116 and improving the durability of the arms B-116, 116.

[0219] In this embodiment, the arms B-116, 116 are provided to protrude radially outward and extend forward from the needle hub B-102. In a configuration in which the connection hole B-106 is provided to extend distally beyond the protruding portions of the arms B-116, 116, the minimum thickness of the arms B-116, 116 is set to be greater than the minimum thickness of the peripheral wall of the connection hole B-106, which is located distally beyond the protruding portions of the arms B-116, 116 in the needle hub B-102. Therefore, by setting the arms B-116, 116 to a thickness greater than the required strength at the distal end of the needle hub B-102, which is greater than the required strength at the protruding portions of the arms B-116, 116, the strength of the arms B-116, 116 can be more advantageously ensured.

[0220] Although the embodiments of Invention B have been described above in detail, Invention B is not limited by the specific descriptions. For example, the specific shape of the connection hole is not particularly limited, and it may have a substantially constant diameter in the axial direction. Furthermore, the inner peripheral surface of connection hole B-48 may have, for example, a curved cross-sectional shape in which the entire surface is curved in the longitudinal section.

[0221] In the above embodiment, the entire outer circumferential surface of the connection port B-56 ​​is configured as a tapered outer circumferential surface B-58. However, for example, the outer circumferential surface of the base end of the connection port B-56 ​​may be configured as a tapered outer circumferential surface B-58, and the outer circumferential surface of the tip end of the connection port B-56 ​​may be configured as a non-inclined cylindrical surface having a substantially constant outer diameter. Furthermore, the tapered outer circumferential surface B-58 of the connection port B-56 ​​may have a curved or bent cross-sectional shape in which the inclination angle changes in the axial direction. Furthermore, the tapered outer circumferential surface B-58 is not essential, and for example, the outer diameter of the connection port B-56 ​​may be substantially constant in the axial direction. Furthermore, for example, the inner diameter of the connection port B-56 ​​may increase or decrease in the axial direction toward the protruding tip.

[0222] The connection port B-56 ​​may be provided, for example, protruding from the peripheral wall of the connection hole B-48 that constitutes the wall of the connection hole B-48, and the bottom B-50 is not essential for the connection hole B-48.

[0223] [Invention C] 21 to 32 show a needle assembly that can be recognized as an independent invention C that can solve a problem different from those of inventions A and B. Invention C relates to a needle assembly that protects the tip of a puncture needle that has been inserted into a blood vessel or the like and left there after it has been removed.

[0224] Indwelling needles have been known for use in transfusions, blood sampling, hemodialysis, etc. An indwelling needle has a structure in which a needle hub is fixed to the base end of a puncture needle with a sharp needle tip. The puncture needle is inserted into a lumen in the body, such as a patient's blood vessel, and an external conduit is connected to the needle hub, allowing transfusions, blood sampling, hemodialysis, etc. to be performed through the lumen of the puncture needle and the external conduit.

[0225] Some puncture needles are equipped with a needle tip protector that protects the tip of the puncture needle after it has been removed from a lumen in the body, for the purposes of preventing accidental punctures after use, preventing repeated use, or facilitating disposal. A needle tip protector and a needle assembly equipped with the same are disclosed, for example, in Japanese Patent Laid-Open No. 2017-196060 (Patent Document 1). That is, with the medical needle with a protector disclosed in Patent Document 1, when the needle tube is pulled out from a blood vessel or the like, the protector moves toward the needle tip relative to the needle tube, and the needle tube removed from the patient is housed within the inner periphery of the protector, preventing the needle tip of the needle tube from being exposed to the outside.

[0226] However, when the inventors studied Patent Document 1 in detail, they discovered a new problem: when the needle tip protector is moved toward the needle tip of the puncture needle, the puncture needle may tilt significantly relative to the needle tip protector. If the puncture needle tilts relative to the needle tip protector, for example, the tip of the puncture needle may come into contact with the patient's skin after being removed from the patient due to the tilt, causing pain to the patient.

[0227] The problem to be solved by Invention C is to provide a needle assembly with a novel structure that can suppress tilting of the puncture needle relative to the needle tip protector.

[0228] Below, we will describe preferred embodiments for understanding Invention C. However, the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may also be recognized and employed independently to the extent possible, and may also be appropriately combined with any of the components described in other embodiments. Therefore, Invention C is not limited to the embodiments described below, and various alternative embodiments may be realized.

[0229] The first aspect of Invention C is a needle assembly including a puncture needle having a needle hub on the base end side, and a needle tip protector having a peripheral wall that is attached to the needle hub and moves relative to the puncture needle to cover the tip of the puncture needle, wherein an abutment portion of the needle tip protector abuts against the needle hub to limit tilting of the needle tip protector relative to the needle hub is provided at an opening portion on the base end side of the peripheral wall.

[0230] According to the needle assembly of this aspect, the needle hub abuts against the abutment provided in the opening at the base end of the peripheral wall, thereby limiting the tilting of the puncture needle relative to the needle tip protector. This prevents the tip of the puncture needle from tilting when, for example, pulling out the puncture needle while holding the needle tip protector. This prevents the needle tip from touching the patient's skin before being retracted into the needle tip protector after removal from the patient.

[0231] In a second aspect of Invention C, in the needle assembly described in the first aspect of Invention C, the opening at the base end of the peripheral wall has a flat shape with the vertical direction being smaller than the horizontal direction, and the abutment portions are provided on both vertical sides of the opening at the base end of the peripheral wall.

[0232] According to the needle assembly of this embodiment, by providing abutment portions on both sides of the opening at the base end of the peripheral wall in the vertical direction where the opening width is small, the tilting of the puncture needle relative to the needle tip protector can be effectively restricted by abutment against the abutment portions of the needle hub.

[0233] The third aspect of Invention C is a needle assembly according to the second aspect of Invention C, wherein a locking portion is provided laterally on the inner periphery of the peripheral wall, which locks with the needle hub when the peripheral wall is moved toward the needle tip, thereby preventing the peripheral wall from retracting toward the base end, thereby preventing the needle tip from being exposed again.

[0234] In the needle assembly of this aspect, a relatively large inner peripheral space of the peripheral wall can be easily secured in the horizontal direction where the opening width is large. Therefore, by utilizing the inner peripheral space of the peripheral wall in the horizontal direction to provide a locking portion that prevents the needle tip protector from moving toward the base end of the puncture needle, it is possible to provide a mechanism that prevents the needle tip from being re-exposed while suppressing an increase in the diameter of the needle tip protector, particularly in the vertical direction.

[0235] A fourth aspect of Invention C is a needle assembly described in any one of the first to third aspects of Invention C, in which, when the needle tip of the puncture needle and the tip of the peripheral wall on the needle tip side are in approximately the same position in the needle axial direction, the tilting of the puncture needle relative to the peripheral wall is limited by the abutment portion to a size that prevents the needle tip from contacting the peripheral wall.

[0236] When the tip of the puncture needle is exposed from the peripheral wall, the tilt of the puncture needle reaches its maximum just before the tip and the tip of the peripheral wall are aligned. Therefore, with the needle tip protector of this embodiment, when the tip and the tip of the peripheral wall are aligned, the tilt of the puncture needle is limited so that the needle tip is positioned more inward than the inner surface of the peripheral wall. This sufficiently suppresses the tilt of the puncture needle relative to the needle tip protector, preventing, for example, the needle tip from coming into contact with the patient.

[0237] A fifth aspect of Invention C is a needle assembly described in any one of the first to fourth aspects of Invention C, in which a large diameter fulcrum portion is provided at the end of the needle hub on the needle tip side, and the large diameter fulcrum portion abuts against the peripheral wall when the puncture needle tilts relative to the peripheral wall.

[0238] With this needle assembly, the center of tilt of the puncture needle relative to the needle tip protector is set at the tip of the needle hub, shortening the distance from the center of tilt of the puncture needle to the needle tip and lengthening the distance from the center of tilt to the abutment part, thereby further suppressing movement of the needle tip by the abutment part when the puncture needle tilts.

[0239] A sixth aspect of Invention C is a needle assembly described in any one of the first to fifth aspects of Invention C, wherein tilting of the puncture needle is restricted by contact with the peripheral wall of the needle hub, and the contact portion includes an opening portion on the base end side of the peripheral wall.

[0240] According to the needle assembly of this aspect, the needle hub directly or indirectly abuts against the peripheral wall, thereby limiting the relative tilting of the needle hub with respect to the peripheral wall. This eliminates the need for special members or parts to form the abutment, and allows the abutment to be realized with a simple structure that utilizes the peripheral wall.

[0241] According to Invention C, it is possible to suppress the relative tilting of the puncture needle with respect to the needle tip protector.

[0242] Hereinafter, an embodiment of the invention C will be described with reference to the drawings.

[0243] Figures 21 to 25 show a needle assembly C-12 equipped with a needle tip protector C-10 as a first embodiment of Invention C. This needle assembly C-12 has a structure in which an indwelling needle C-14 is inserted through the needle tip protector C-10 so as to be movable in the needle axial direction. In the following description, unless otherwise specified, the distal end refers to the left side in Figure 21, which is the needle tip C-20 side of the puncture needle C-16 (described later), and the proximal end refers to the right side in Figure 21, which is the rear side in the puncture direction of the indwelling needle C-14. Furthermore, as a general rule, the up-down direction refers to the vertical direction in Figure 22, which is the vertical direction, and the left-right direction refers to the horizontal direction in Figure 21. For ease of viewing, in Figures 21 to 32 relating to Invention C, the "C-" has been omitted from each reference symbol "C-XX" (XX is a number corresponding to the location). In addition, to make it easier to understand that FIGS. 21 to 32 are drawings relating to Invention C, [Invention C] is written in FIGS.

[0244] More specifically, the indwelling needle C-14 comprises a puncture needle C-16 and a needle hub C-18. The puncture needle C-16 is made of a metal such as stainless steel, and has a sharp, tapered tip C-20 at one end. A through-hole C-22 is formed at the tip of the puncture needle C-16, allowing blood to easily flow into the lumen of the puncture needle C-16.

[0245] The needle hub C-18 has a generally cylindrical shape overall, and the base end portion of the puncture needle C-16 is inserted and fixed in the tip portion. This allows the inner cavity of the needle hub C-18 to communicate with the inner cavity of the puncture needle C-16 in the needle axial direction. The needle hub C-18 has a needle support part C-24 that forms the tip portion and a protector connecting part C-26 that forms the base portion.

[0246] The needle support C-24 has a generally cylindrical shape and is made of, for example, a hard synthetic resin. The inner diameter of the tip of the needle support C-24 is generally the same as the outer diameter of the puncture needle C-16. The inner peripheral surface of the tip of the needle support C-24 is provided with an annular positioning protrusion C-28 that protrudes inward. The base end of the puncture needle C-16 is inserted through the opening at the tip of the needle support C-24, and the base end of the puncture needle C-16 and the positioning protrusion C-28 come into contact with each other, thereby positioning the puncture needle C-16 in the needle axial direction (left-right direction in FIG. 21) relative to the needle hub C-18. The puncture needle C-16 and the needle support C-24 may be bonded together, if necessary.

[0247] The needle support part C-24 has a tapered surface C-30 on the outer circumferential surface of the middle part in the needle axis direction, which gradually increases in diameter toward the tip side, so that the middle part in the needle axis direction of the needle support part C-24 having the tapered surface C-30 is a small-diameter cylindrical part C-32 whose diameter is smaller than that of the tip and base end parts.

[0248] A locking recess C-34 that opens onto the outer circumferential surface is formed in the needle support portion C-24 at the distal end of the tapered surface C-30. The locking recess C-34 is annular and has a substantially constant cross-sectional shape all around. The minimum outer diameter of the needle support portion C-24 at the location where the locking recess C-34 is formed is substantially the same as the minimum outer diameter of the base end of the small-diameter cylindrical portion C-32.

[0249] An annular large-diameter fulcrum C-36 protrudes from the outer peripheral surface of the needle support C-24, closer to the tip than the locking recess C-34. The large-diameter fulcrum C-36 is provided at or near the tip of the needle support C-24, and in this embodiment, constitutes the tip of the needle support C-24. The outer diameter of the needle support C-24 at the location where the large-diameter fulcrum C-36 is formed is larger than the outer diameter of the tip, which is the maximum outer diameter of the small-diameter cylindrical portion C-32.

[0250] The base-end side surface constituting the inner surface of the locking recess C-34 is an annular base-end restriction surface C-38 extending in the axis-perpendicular direction, and the bottom surface of the locking recess C-34 and the tapered surface C-30 are connected in a stepped manner via the base-end restriction surface C-38. The tip-end side surface constituting the inner surface of the locking recess C-34 is an annular tip-end restriction surface C-40 extending in the axis-perpendicular direction, and the bottom surface of the locking recess C-34 and the outer peripheral surface of the large-diameter fulcrum portion C-36 are connected in a stepped manner via the tip-end restriction surface C-40. The axis-perpendicular dimension of the base-end restriction surface C-38 formed by the base-end inner surface of the locking recess C-34 is slightly larger than the axis-perpendicular dimension of the tip-end restriction surface C-40.

[0251] The protector connecting portion C-26 is formed of a hard synthetic resin, for example, similar to the needle support portion C-24. The protector connecting portion C-26 has a stepped, generally cylindrical shape, with a small-diameter connecting tube portion C-42 at its distal end and a large-diameter connecting tube portion C-44 at its proximal end. The protector connecting portion C-26 is fixed to the needle support portion C-24 by inserting the proximal end of the needle support portion C-24 into the connecting tube portion C-42 and, if necessary, by gluing or welding. A generally rectangular recess C-46 is formed on the longitudinal surface (the up-down direction in FIG. 22) of the protector connecting portion C-26. In this embodiment, the recess C-46 is provided on the surface of the connecting tube portion C-42 as shown in FIG. 21, but it may also be provided on the surface of the connecting tube portion C-44 or may be provided across the connecting tube portion C-42 and the connecting tube portion C-44.

[0252] The protector connecting part C-26 is fixed to the external conduit C-47 by inserting the tip of the external conduit C-47 into the connecting tube part C-44 and applying adhesive or welding as necessary. By connecting the needle support part C-24 and the external conduit C-47 to both sides of the protector connecting part C-26, the inner cavity of the puncture needle C-16 and the inner cavity of the needle hub C-18 are communicated with the external conduit C-47, and a fluid flow path C-48 extending from the tip opening of the puncture needle C-16 to the external conduit C-47 is provided in the indwelling needle C-14.

[0253] The connecting tubular portion C-44 is provided with a pair of engaging arms C-50, 50 that extend toward the tip. The engaging arms C-50, 50 are arranged opposite each other in the radial direction and extend around the outer periphery of the connecting tubular portion C-42 further toward the tip than the connecting tubular portion C-42. The engaging arms C-50, 50 are arranged spaced apart from the outer periphery of the connecting tubular portion C-42, and the connecting portion with the connecting tubular portion C-44 is thin-walled and narrow, allowing elastic deformation in the direction of approaching each other when subjected to an external force.

[0254] A hook C-52 is formed at the tip of each of the engaging arms C-50, 50. The hook C-52 protrudes outward in the opposing direction of the engaging arms C-50, 50. The pair of hooks C-52, 52 move in directions approaching each other as the engaging arms C-50, 50 elastically deform in the approaching direction.

[0255] As shown in Figure 26, the needle tip protector C-10 has a generally cylindrical shape extending in the needle axis direction as a whole, and is integrally molded from a hard synthetic resin such as polypropylene, polycarbonate, glycol-modified polyethylene terephthalate, ABS resin, etc. The needle tip protector C-10 has a cylindrical peripheral wall C-54, and an inner hole C-56 that penetrates in the needle axis direction is formed on the inner periphery of the peripheral wall C-54.

[0256] The peripheral wall C-54 has a cylindrical portion C-58 at the tip end with a cross section of an approximately perfect ring shape, and an expanded portion C-60 at the base end which has a larger diameter than the cylindrical portion C-58 and expands outward, and the shape differs in the needle axial direction.

[0257] As shown in FIG. 27, the expansion section C-60 has a substantially elliptical cylindrical shape, and the width dimension of the outer peripheral surface in the large-diameter direction (horizontal direction) in FIG. 26 (the vertical direction) is larger than the width dimension of the outer peripheral surface in the small-diameter direction (the vertical direction) in FIG. 26. Of the wall portions constituting the expansion section C-60, the portions constituting the vertical wall portion are narrow portions C-62, 62, while the portions constituting the horizontal wall portion are wide portions C-64, 64, and the opposing directions of the narrow portions C-62, 62 and the wide portions C-64, 64 are perpendicular to each other. Note that the expansion section C-60 may have substantially the same dimensions in the vertical and horizontal directions. The cross-sectional shape of the outer peripheral surface of the expansion section C-60 may be circular, rectangular, or the like.

[0258] The outer diameter of the outer peripheral surface of the wide portions C-64, 64 gradually increases from the distal end toward the proximal end. The outer peripheral surface of the cylindrical portion C-58 and the outer peripheral surface of the wide portions C-64, 64 are smoothly connected. The wall thickness from the cylindrical portion C-58 to the wide portions C-64, 64 is substantially constant in the needle axial direction and is smaller than the wall thickness of the narrow portions C-62, 62. In other words, the narrow portions C-62, 62 are thicker than the cylindrical portion C-58 and the wide portions C-64, 64. An internal space C-66 having a flat cross section with a horizontal dimension larger than a vertical dimension is formed on the inner periphery of the expanded portion C-60 at the proximal end of the inner hole C-56 that penetrates the needle tip protector C-10. The horizontal interior dimensions of the internal space C-66 gradually increase toward the base end.

[0259] The wide portions C-64, 64 are formed with through windows C-68, 68 that penetrate in the plate thickness direction and serve as needle hub engagement portions. The circumferential dimension of the through windows C-68, 68 is larger than the circumferential dimension of the hooks C-52, 52. In this embodiment, when molding the needle tip protector C-10, the mold for molding the outer peripheral surface is split in the vertical direction, so the through windows C-68, 68 are shaped so that no undercuts occur when the mold is demolded in the vertical direction.

[0260] A recess C-70 is formed in the circumferential center portion on the outer peripheral surface of the narrow width portions C-62, 62. The recess C-70 has a substantially rectangular opening on the outer surface in the vertical direction, and is arranged circumferentially spaced apart from the through windows C-68, 68.

[0261] As shown in Figure 24, an annular stepped surface C-74 is formed on the inner peripheral surface of the peripheral wall C-54 at the front end of the expanded portion C-60 in the axis-perpendicular direction. The diameter of the inner peripheral surface of the peripheral wall C-54 is larger on the distal side than on the proximal side of the stepped surface C-74. The dimension of the stepped surface C-74 in the axis-perpendicular direction is smaller than the dimension of the distal restriction surface C-40 of the locking recess C-34 in the axis-perpendicular direction.

[0262] In addition, a pair of locking pieces C-76, 76 are provided in the internal space C-66 as locking portions protruding from the inner peripheral surface of the expanded portion C-60 of the peripheral wall C-54 into the internal space C-66. As shown in Figures 24 and 27, the locking pieces C-76, 76 are integrally formed with the wide portions C-64, 64 of the expanded portion C-60 of the peripheral wall C-54. The locking pieces C-76, 76 are arranged on the inner peripheral side of the wide portions C-64, 64 at positions corresponding to the wide portions C-64, 64. The locking pieces C-76, 76 are arranged opposite each other in the horizontal direction and are spaced apart from each other in the circumferential direction. The locking pieces C-76, 76 protrude toward the base end of the peripheral wall C-54 on the base end side of the stepped surface C-74. The locking pieces C-76, 76 extend from the stepped surface C-74 toward the base end side substantially parallel to the needle axis direction, and are each curved in the circumferential direction.

[0263] A pair of locking claws C-78, 78 are formed at the protruding tip (proximal end in the needle axis direction) of the locking pieces C-76, 76, bending inward and protruding. The inner peripheral surfaces of the locking claws C-78, 78 are curved in the circumferential direction, as shown in Figure 27, and the radius of curvature of the inner peripheral surfaces at the protruding tips of the locking claws C-78, 78 is approximately equal to the radius of curvature of the outer peripheral surface of the small-diameter cylindrical portion C-32 of the needle support portion C-24. The radial distance between the opposing surfaces at the protruding tips of the locking claws C-78, 78 is approximately equal to the outer diameter of the small-diameter cylindrical portion C-32, but is smaller than the maximum outer diameter of the tip portion of the tapered surface C-30. However, the radial distance between the opposing surfaces at the protruding tips of the locking claws C-78, 78 may be slightly smaller or larger than the outer diameter of the small-diameter cylindrical portion C-32.

[0264] Furthermore, the proximal end surfaces C-80, 80 of the locking claws C-78, 78 have an inner circumferential portion formed as a vertical surface C-80a, 80a that extends in the axis-perpendicular direction, and an outer circumferential portion formed as an inclined surface C-80b, 80b that slopes toward the distal end in the needle axis direction. In this embodiment, the axis-perpendicular dimension of the vertical surface C-80a, 80a is approximately the same as or slightly larger than the axis-perpendicular dimension of the proximal restriction surface C-38 of the locking recess C-34. As a result, when the locking claws C-78, 78 abut against the proximal restriction surface C-38, as described below, the entire surface of the proximal restriction surface C-38 abuts against the vertical surface C-80a, 80a, ensuring a sufficiently large contact area. Furthermore, the inclined surfaces C-80b, 80b located on the outer periphery of the vertical surfaces C-80a, 80a are inclined toward the tip side in the needle axial direction as they approach the outer periphery, so that the vertical surfaces C-80a, 80a and the base end regulating surface C-38 abut without interference from the inclined surfaces C-80b, 80b.

[0265] In addition, the protruding tips (base ends in the needle axis direction) of the locking claws C-78, 78 are located further to the tip side in the needle axis direction than the base end of the expanding portion C-60. Therefore, the entirety of the locking pieces C-76, 76 is housed in the internal space C-66 of the expanding portion C-60.

[0266] The tip portion of the needle tip protector C-10 is provided with a wing-like portion C-82. The wing-like portion C-82 is formed, for example, from a soft synthetic resin. The wing-like portion C-82 is formed integrally with a cylindrical fitting portion C-84, with plate-like connecting portions C-86, 86 protruding in the tangential direction of the fitting portion C-84, and a wing main body C-88 is formed integrally with each of the connecting portions C-86, 86 at the tip end thereof protruding from the fitting portion C-84. The wing-like portion C-82 is attached to the peripheral wall C-54 of the needle tip protector C-10 by fitting the fitting portion C-84 onto the tip end of the cylindrical portion C-58.

[0267] When the indwelling needle C-14 is inserted through the inner hole C-56 of the needle tip protector C-10, the needle tip protector C-10 is fitted onto the indwelling needle C-14 to form the needle assembly C-12. In the initial state before use of the needle assembly C-12 shown in Figure 21, the needle tip C-20 of the indwelling needle C-14 is positioned distal to the needle tip protector C-10 and is exposed. In this initial state, hooks C-52, 52 on the needle hub C-18 of the indwelling needle C-14 are inserted into and engaged with through-holes C-68, 68 provided in the expanded portion C-60 of the needle tip protector C-10. This connects the needle tip protector C-10 and the needle hub C-18, maintaining the protruding state of the needle tip C-20, and restricting the movement of the puncture needle C-16 toward the base end in the needle axial direction due to resistance during puncture, for example, when holding the wing-shaped portion C-82 and performing a puncture.

[0268] In the initial state of the needle assembly C-12, the locking claws C-78, 78 of the needle tip protector C-10 abut against the outer peripheral surface of the small diameter cylindrical portion C-32 of the needle support portion C-24. Note that these locking claws C-78, 78 may be pressed slightly outward by abutting against the outer peripheral surface of the small diameter cylindrical portion C-32, or may be slightly spaced apart from the outer peripheral surface of the small diameter cylindrical portion C-32.

[0269] The needle assembly C-12 is used for infusion, blood sampling, and hemodialysis via the fluid flow path C-48 by inserting the puncture needle C-16 into a patient's blood vessel and leaving the indwelling needle C-14. Since the needle assembly C-12 of this embodiment is provided with a winged portion C-82, it is possible to insert the puncture needle C-16 of the indwelling needle C-14 while pinching the winged portion C-82. When the indwelling needle C-14 is left in the inserted state, it can be fixed with tape at the position of the winged portion C-82, allowing it to be fixed with a wide contact area with the skin.

[0270] To remove the indwelling needle C-14, the engagement arms C-50, 50 of the needle hub C-18 are pressed inward with the fingers while the needle tip protector C-10 remains fixed with tape to the winged portion C-82. This releases the engagement between the hooks C-52, 52 and the through-holes C-68, 68, allowing the indwelling needle C-14 to be moved proximally relative to the needle tip protector C-10. By moving the indwelling needle C-14 proximally relative to the needle tip protector C-10 and removing the puncture needle C-16 from the skin, the needle tip protector C-10 moves toward the needle tip C-20 relative to the indwelling needle C-14.

[0271] When the hooks C-52, 52 and the through windows C-68, 68 are disengaged, the indwelling needle C-14 will not move proximally relative to the needle tip protector C-10 unless an external force is applied to the indwelling needle C-14 to move it proximally relative to the needle tip protector C-10. That is, the locking claws C-78, 78 abut against the tapered surface C-30, which increases in diameter toward the tip, preventing the indwelling needle C-14 from moving proximally relative to the needle tip protector C-10. This prevents the needle tip C-20 of the indwelling needle C-14 from being unintentionally protected by the needle tip protector C-10.

[0272] By moving the indwelling needle C-14 toward the base end relative to the needle tip protector C-10, the locking claws C-78, 78 slide against the tapered surface C-30, and the elastic restoring force of the locking pieces C-76, 76 acts as a biasing force pressing the locking claws C-78, 78 against the tapered surface C-30. Therefore, the user can move the indwelling needle C-14 while feeling the resistance caused by the contact between the locking claws C-78, 78 and the tapered surface C-30, confirming the feeling that the indwelling needle C-14 is being pulled out of the needle tip protector C-10.

[0273] When the indwelling needle C-14 is moved toward the base end relative to the needle tip protector C-10, the indwelling needle C-14 may tilt relative to the needle tip protector C-10. That is, the locking claws C-78, 78 are in sliding contact with the tapered surface C-30, and a gap is provided between the needle support portion C-24 of the indwelling needle C-14 and the peripheral wall C-54 of the needle tip protector C-10. Therefore, when the hooks C-52, 52 and the through windows C-68, 68 are disengaged and the indwelling needle C-14 moves toward the base end relative to the needle tip protector C-10, the central axis of the needle tip protector C-10 may tilt relative to the needle axis, which is the central axis of the indwelling needle C-14. When the indwelling needle C-14 tilts vertically relative to the needle tip protector C-10, the indwelling needle C-14 abuts against the peripheral wall C-54 of the needle tip protector C-10 at the large diameter fulcrum C-36 provided at the tip of the needle hub C-18. Therefore, the vertical tilt of the indwelling needle C-14 relative to the needle tip protector C-10 occurs around the abutment point between the large diameter fulcrum C-36 and the peripheral wall C-54, as shown in Figure 28.

[0274] The needle hub C-18 directly abuts the narrow portion C-62 of the expanded portion C-60 at a position sufficiently proximal to the abutment point between the large-diameter fulcrum portion C-36, which serves as the tilting center, and the peripheral wall C-54, thereby limiting the vertical tilt of the indwelling needle C-14 relative to the needle tip protector C-10. Thus, a vertical abutment portion C-90, which functions as a tilt limiter that limits the tilt of the indwelling needle C-14 by abutting the needle hub C-18, is provided in the opening on the proximal side of the peripheral wall C-54 of the needle tip protector C-10. In this embodiment, the abutment portion C-90 is formed by the inner peripheral portions of the narrow portions C-62, 62 that form the opening on the proximal side of the peripheral wall C-54, and the abutment portions C-90 are provided on both vertical sides.

[0275] By restricting the tilting of the indwelling needle C-14 by the contact portion C-90, the tilting of the puncture needle C-16 is restricted and the movement of the needle tip C-20 in the direction perpendicular to the axis is suppressed when the indwelling needle C-14 is pulled out toward the base end side relative to the needle tip protector C-10. Therefore, for example, a problem such as the needle tip C-20 of the puncture needle C-16 being pulled out of a blood vessel or the like coming into contact with the patient's skin due to the vertical tilting of the indwelling needle C-14 and causing injury to the patient can be avoided.

[0276] Preferably, when the needle tip C-20 shown in Fig. 29 is at the same position in the needle axial direction relative to the tip of the peripheral wall C-54 of the needle tip protector C-10, the tilting of the indwelling needle C-14 is restricted by the abutment portion C-90 so that the needle tip C-20 does not come into contact with the peripheral wall C-54 due to tilting of the indwelling needle C-14. As a result, when the needle tip C-20 is exposed at the tip beyond the peripheral wall C-54 of the needle tip protector C-10, the needle tip C-20 will not be positioned further outward than the peripheral wall C-54, effectively preventing the needle tip C-20 from coming into contact with the patient's skin, etc.

[0277] When the needle tip C-20 is in the same position in the needle axial direction relative to the tip of the peripheral wall C-54 of the needle tip protector C-10, the large diameter fulcrum C-36, which is the center of tilting of the indwelling needle C-14 relative to the needle tip protector C-10, is desirably located closer to the base end than the axial center of the needle tip protector C-10. In other words, in the above state, it is desirably that the distance from the needle tip C-20 to the large diameter fulcrum C-36 is longer than 1 / 2 the axial length of the needle tip protector C-10. More preferably, the distance from the needle tip C-20 to the large diameter fulcrum C-36 is longer than 2 / 3 the axial length of the needle tip protector C-10.

[0278] The expanded portion C-60 constituting the base end portion of the peripheral wall C-54 has a flattened shape with a vertical dimension smaller than a horizontal dimension, and the vertical interior dimension is smaller than the horizontal interior dimension. As a result, when the indwelling needle C-14 tilts vertically relative to the needle tip protector C-10, the needle hub C-18 quickly abuts against the abutment portion C-90 at a relatively small tilting stage, limiting the tilting of the indwelling needle C-14 to a small extent. Furthermore, because the base end portion of the needle tip protector C-10 has a small vertical interior dimension but a sufficient horizontal interior dimension, it is possible to effectively limit the tilting of the indwelling needle C-14 in the vertical direction while ensuring space in the horizontal direction for arranging the locking pieces C-76, 76, etc.

[0279] The lateral tilting of the indwelling needle C-14 relative to the needle tip protector C-10 is limited to some extent by the large diameter fulcrum C-36 of the needle hub C-18 abutting against the inner peripheral surface of the peripheral wall C-54 and the locking pieces C-76, 76 abutting against the outer peripheral surface of the needle hub C-18. As a result, in the needle tip protector C-10 of this embodiment, lateral abutment portions are provided on the locking pieces C-76, 76, and the locking pieces C-76, 76 form a lateral tilt limiting portion.

[0280] 30 and 31, by moving the indwelling needle C-14 backward to a predetermined position relative to the needle tip protector C-10 (moving the needle tip protector C-10 forward toward the needle tip C-20 of the indwelling needle C-14), the needle tip C-20 of the puncture needle C-16 is covered by the needle tip protector C-10. Furthermore, the locking claws C-78, 78 provided on the free ends of the locking pieces C-76, 76 move onto the opening of the locking recess C-34, and the locking claws C-78, 78, which have elastically restored their shape, enter the locking recess C-34. Then, the vertical surfaces C-80a, 80a of the locking claws C-78, 78 abut and engage with the base end regulating surface C-38 of the locking recess C-34, thereby restricting the movement of the indwelling needle C-14 toward the tip side relative to the needle tip protector C-10 and preventing the needle tip C-20 of the indwelling needle C-14 from being exposed again.

[0281] The stepped surface C-74 provided at the front end portion of the locking pieces C-76, 76 and the distal end side restricting surface C-40 of the locking recess C-34 come into contact and lock, restricting movement of the indwelling needle C-14 toward the proximal end. This prevents the indwelling needle C-14 from being pulled out toward the proximal end from the needle tip protector C-10. Therefore, movement of the indwelling needle C-14 in both axial directions relative to the needle tip protector C-10 is restricted, and the protection of the needle tip C-20 by the needle tip protector C-10 is maintained.

[0282] In this embodiment, a pair of locking pieces C-76, 76 are provided, and together with the fact that the locking pieces C-76, 76 are integrally molded with the peripheral wall C-54 of the needle tip protector C-10, problems such as rattle of the needle tip protector C-10 relative to the indwelling needle C-14 can be effectively prevented when the locking claws C-78, 78 are engaged with the proximal-end regulating surface C-38. Thus, by providing two or more locking pieces C-76, the needle tip protector C-10 is more reliably prevented from retracting toward the proximal end relative to the indwelling needle C-14, thereby more reliably preventing re-exposure of the needle tip C-20. In this case, it is preferable that the multiple locking pieces C-76 be arranged approximately symmetrically about the central axis of the needle tip protector C-10.

[0283] Furthermore, when the needle tip C-20 is housed in the peripheral wall C-54 of the needle tip protector C-10, it is desirable that the tilting of the indwelling needle C-14 relative to the peripheral wall C-54 be limited to a size that prevents the needle tip C-20 from contacting the inner surface of the peripheral wall C-54.

[0284] With the needle tip C-20 of the indwelling needle C-14 protected by the needle tip protector C-10, the tape on the winged portion C-82 is released and the needle assembly C-12 is removed from the patient. However, the procedure for protecting the needle tip C-20 is not limited to the above procedure. Specifically, for example, the tape on the winged portion C-82 may be released, the entire needle assembly C-12 may be moved back to remove the puncture needle C-16 from the blood vessel, and then the indwelling needle C-14 may be moved back relative to the needle tip protector C-10 to protect the needle tip C-20 of the puncture needle C-16.

[0285] When the locking claws C-78, 78 enter the locking recess C-34, the tips of the locking claws C-78, 78 come into contact with the bottom surface of the locking recess C-34, allowing the user to hear the impact and sound of this contact. This avoids the possibility that the user will interrupt the operation of withdrawing the indwelling needle C-14 midway, and more reliably protects the needle tip C-20 with the needle tip protector C-10.

[0286] In the needle tip protector C-10 and needle assembly C-12 constructed as described above, the entire locking pieces C-76, 76 that prevent the needle tip C-20 of the indwelling needle C-14 from being re-exposed are housed within the cylindrical peripheral wall C-54. This makes it virtually impossible to unintentionally contact the locking pieces C-76, 76 from the outside. Therefore, when the needle tip C-20 of the indwelling needle C-14 is protected by the needle tip protector C-10, it is possible to effectively prevent the needle tip C-20 from being re-exposed from the needle tip protector C-10 by unintentionally releasing the lock between the locking pieces C-76, 76 and the locking recess C-34.

[0287] When the locking pieces C-76, 76 are locked to the needle hub C-18, for example, if an external force, such as a bending force, is applied to the indwelling needle needle tip protector C-10 and / or the needle hub C-18, the locking pieces C-76, 76 can come into contact with the wide portions C-64, 64 located away from the outer periphery. This limits the deformation of the locking pieces C-76, 76 toward the outer periphery, reducing the risk of the locking pieces C-76, 76 being released from their locking to the needle hub C-18, and therefore the protection state of the needle tip C-20 of the indwelling needle C-14 can be stably maintained.

[0288] The locking pieces C-76, 76 are provided on an expanded portion C-60 expanded at the base end side of the needle tip protector C-10. This allows the size of the locking pieces C-76, 76 to be sufficiently ensured while also allowing the outer diameter dimension of the needle support portion C-24 of the needle hub C-18, which is inserted between the locking pieces C-76, 76, to be sufficiently large. Furthermore, in this embodiment, the expanded portion C-60 has a substantially elliptical shape, i.e., the portion that comes into contact with the patient has a smooth curved shape without bends or corners, and its outer surface is smoothly continuous with the outer surface of the cylindrical portion C-58, thereby reducing the risk of the expanded portion C-60 or the like coming into contact with the patient and causing pain to the patient.

[0289] Since the locking pieces C-76, 76 are provided inside the wide portions C-64, 64 that constitute the expansion portion C-60, the wide portions C-64, 64 are prevented from becoming thick, thereby suppressing the occurrence of dimensional errors and deterioration in quality due to the inclusion of air bubbles in the member during molding, the occurrence of sink marks and voids, etc. Furthermore, it is preferable that the locking portions (locking pieces C-76, 76) are provided so as to extend in the same direction (toward the base end in the axial direction) as the wide portions C-64, 64. This prevents the expansion portion C-60 from becoming larger than necessary, makes it possible to effectively utilize the space inside the wide portions C-64, 64, and prevents the wide portions C-64, 64 from becoming thick.

[0290] Since the locking pieces C-76, 76 extend toward the base end side, they do not get caught when the indwelling needle C-14 is pulled out from the needle tip protector C-10, and smooth pulling out can be achieved.

[0291] Since a pair of locking pieces C-76, 76 are provided facing each other in the radial direction, when the needle tip C-20 is protected by the needle tip protector C-10, that is, when the locking pieces C-76, 76 are locked into the locking recess C-34, the fitting tube portion C-84 is clamped radially between the locking pieces C-76, 76. Therefore, the needle tip protector C-10 and the indwelling needle C-14 (needle support portion C-24) do not wobble radially, and the state in which the needle tip C-20 of the indwelling needle C-14 is protected by the needle tip protector C-10 can be stably maintained.

[0292] The mutually engaging vertical surfaces C-80a, 80a of the locking claws C-78, 78 and the proximal end restriction surface C-38 of the locking recess C-34 both extend in the axially perpendicular direction. Furthermore, the mutually engaging stepped surface C-74 and the distal end restriction surface C-40 of the locking recess C-34 both extend in the axially perpendicular direction. Therefore, the needle tip protector C-10, which includes the vertical surfaces C-80a, 80a and the stepped surface C-74, and the needle hub C-18, which includes the proximal end restriction surface C-38 and the distal end restriction surface C-40, are free from undercuts and easy to mold. Furthermore, the abutment force and abutment reaction force due to the abutment between the vertical surfaces C-80a, 80a and the proximal end restriction surface C-38 act without tilting relative to the axial direction. Similarly, the contact force and contact reaction force due to the contact between the stepped surface C-74 and the distal end side restriction surface C-40 act without tilting in the axial direction. In addition, the contact area of ​​each can be sufficiently secured, so that the needle tip protector C-10 can be more reliably prevented from moving toward the distal end and the proximal end relative to the indwelling needle C-14.

[0293] By providing the locking pieces C-76, 76 so as to protrude into the inner peripheral space of the peripheral wall C-54, for example, when manufacturing the needle tip protector C-10 by molding, the mold that molds the inner peripheral side of the needle tip protector C-10 can be removed in the needle axis direction of the needle tip protector C-10. Therefore, the number of types of molds can be reduced, and the manufacturing efficiency of the needle tip protector C-10 can also be improved.

[0294] The needle tip protector C-10 has an inner peripheral shape formed by, for example, axially assembled molds, and an outer peripheral shape formed by vertically assembled molds. Because the outer peripheral surface of the needle tip protector C-10 is formed by vertically assembled molds, a parting line C-92 protruding from the parting surface of the molds is formed on the lateral outer surface of the needle tip protector C-10, extending in the axial direction, as shown in Figure 22. This makes it difficult for the parting line C-92 to come into contact with the patient, thereby avoiding pain caused by contact with the parting line C-92.

[0295] A gate mark C-94, which is a mark left by a gate used to fill a mold cavity with resin material during molding of the needletip protector C-10, is provided within the recess C-70 of the needletip protector C-10 (see Figure 21). Therefore, even if the gate mark C-94 protrudes from the vertical surface of the needletip protector C-10, it is contained within the recess C-70, making it difficult for patients and others to touch the gate mark C-94. Furthermore, because the opening area of ​​the recess C-70 is small relative to the size of a fingertip, it is difficult for a fingertip to enter the recess C-70, and medical professionals who hold and operate the needletip protector C-10 with their fingertips also find it difficult to touch the gate mark C-94 in the recess C-70. Therefore, even if the gate is a pin gate that is pulled off during mold removal and leaves a protruding gate mark C-94, contact with the gate mark C-94 is unlikely to be a problem.

[0296] Although filling the resin material from the wider cavity of the mold reduces the likelihood of resin material filling defects, if resin material is to be filled from the larger diameter expansion portion C-60, the gate mark C-94 will be formed on the outer periphery of the smaller diameter needle support portion C-24, making it more likely to come into contact with the patient, etc. However, since the gate mark C-94 is housed within the recess C-70, it is possible to prevent contact with the gate mark C-94 by the patient, etc., while setting the gate position at the base end portion of the larger diameter needle tip protector C-10, thereby enabling efficient manufacture of the needle tip protector C-10.

[0297] Similarly, the protector connecting portion C-26 of the needle hub C-18 is also formed using a mold divided into upper and lower halves, and the parting line C-96 protrudes from the horizontal surface, making it difficult for the parting line C-96 of the protector connecting portion C-26 to come into contact with a patient. Furthermore, the gate mark C-98 of the protector connecting portion C-26 protrudes from the bottom surface of the recess C-46 formed in the vertical surface of the protector connecting portion C-26, and the gate mark C-98 is contained in the recess C-46. Therefore, even though the gate mark C-98 is formed on the vertical surface of the protector connecting portion C-26, the gate mark C-98 is unlikely to come into contact with a patient. The opening area of ​​the recess C-46 is small relative to the size of a fingertip, so that a medical professional holding and operating the needle hub C-18 with their fingertips is unlikely to come into contact with the gate mark C-98 in the recess C-46. The gate trace C-98 may be provided on the wide portion C-64, 64 side. This reduces the likelihood of weld lines occurring in the wide portion C-64, 64, which serves as an engagement portion having the through window C-68, 68, which is likely to be thin-walled even within the needle tip protector C-10. As a result, the strength of the wide portion C-64, 64 is increased, allowing the engagement arms C-50, 50 of the needle hub C-18 to be more firmly engaged with the needle tip protector C-10. This avoids unintended separation of the needle hub C-18 and the needle tip protector C-10 and prevents malfunction of the needle tip protection mechanism. Furthermore, it also prevents problems such as the wide portion C-64, 64 being damaged by external force, which could cause the needle tip protection mechanism to malfunction.

[0298] Although the embodiment of Invention C has been described above in detail, Invention C is not limited to the specific description. In the above embodiment, both the abutment C-90 that limits the vertical tilt of the indwelling needle C-14 relative to the needle tip protector C-10 and the abutment (locking pieces C-76, 76) that limits the horizontal tilt are provided, but it is also possible to provide only the vertical abutment.

[0299] In the above embodiment, a structure was exemplified in which the abutment portion that limits the lateral tilting of the indwelling needle C-14 relative to the needle tip protector C-10 is constituted by locking pieces C-76, 76, but the lateral abutment portion can also be constituted, for example, by abutment between the needle hub C-18 of the indwelling needle C-14 and the peripheral wall C-54 (wide portions C-64, 64) of the needle tip protector C-10.

[0300] The abutment portion C-90 can adjust the vertical clearance of the indwelling needle C-14 relative to the needle hub C-18, for example, by thickening the narrow portions C-62, 62 toward the inner periphery or by providing a protrusion protruding from the narrow portions C-62, 62 toward the inner periphery. This allows for adjustment of the allowable range of tilting of the indwelling needle C-14 relative to the needle tip protector C-10. Note that forming a recess on the inner periphery of the narrow portions C-62, 62 or thinning the narrow portions C-62, 62 toward the inner periphery allows for greater tilting of the indwelling needle C-14 relative to the needle tip protector C-10.

[0301] For example, as shown in Figure 32, deformation limiting portions C-140, 140 that limit the amount of deformation of the locking pieces C-76, 76 outward can be provided in the internal space C-66 of the expanding portion C-60. The deformation limiting portion C-140 is formed by a protrusion C-142 that protrudes from the inner peripheral surface of the expanding portion C-60 toward the base end. For example, multiple protrusions C-142 may be provided side by side and spaced apart from each other in the circumferential direction between the narrow portions C-62, 62. The protrusions C-142 are provided at a predetermined distance laterally (vertically in Figure 32) relative to the locking pieces C-76, allowing elastic deformation of the locking pieces C-76 outward in the lateral direction.

[0302] By providing such deformation limiting portions C-140, 140, the outward lateral movement of the locking pieces C-76, 76 is limited by the deformation limiting portions C-140, 140, making it difficult for the locking pieces C-76, 76 to disengage from the base-end restricting surfaces C-38, 38. Furthermore, by limiting the outward lateral deformation of the locking pieces C-76, 76, the lateral tilting of the indwelling needle C-14 and the needle tip protector C-10 is effectively limited by the locking pieces C-76, 76. In the structure of Figure 32, the needle hub C-18 of the indwelling needle C-14 abuts against the deformation limiting portions C-140, 140 via the locking pieces C-76, 76, thereby limiting the lateral tilting of the indwelling needle C-14. Therefore, in the structure of Figure 32, the abutment portion that abuts against the needle hub C-18 is constituted by the locking pieces C-76, 76, and the tilt limiting portion that limits the lateral tilting of the needle hub C-18 is constituted by the locking pieces C-76, 76 and the wide portions C-64, 64 of the peripheral wall C-54 that are provided with deformation amount limiting portions C-140, 140.

[0303] In the above embodiment, the opening portion on the base end side of the peripheral wall C-54 is an expanded portion C-60 having narrow portions C-62, 62 and wide portions C-64, 64, and has a flat shape in which the vertical dimension is smaller than the horizontal dimension. However, the opening portion on the base end side of the peripheral wall C-54 may have, for example, a true circular cross section. Furthermore, the opening portion on the base end side of the peripheral wall C-54 has a larger diameter than the cylindrical portion C-58, which is the distal portion. However, the peripheral wall C-54 may have a substantially constant diameter throughout the axial direction, or the proximal portion may have a smaller diameter than the distal portion. The cross-sectional shape of the peripheral wall C-54 is preferably a round or elliptical shape without any corners, but it may also be, for example, a polygonal or irregular shape.

[0304] The large diameter fulcrum C-36, which is the center of tilting of the indwelling needle C-14 and the needle tip protector C-10, is preferably provided at the tip portion of the needle hub C-18, but can also be provided, for example, at the axial middle portion of the needle support C-24 of the needle hub C-18. The large diameter fulcrum only needs to be located distal to the abutment portion provided at the opening on the base end side of the needle tip protector C-10 when the needle tip C-20 is housed in the needle tip protector C-10.

[0305] [Invention D] 33 to 37 show a needle assembly that can be recognized as an independent invention D that can solve a problem different from those of inventions A to C. Invention D relates to a needle assembly used, for example, as an indwelling needle that is inserted into a blood vessel and left indwelling.

[0306] Needle assemblies have been known for use in infusions, medication, artificial dialysis, etc. As shown in JP 2017-196060 A (Patent Document 1), for example, needle assemblies have a structure in which a needle hub is provided on the proximal end side of a hollow needle.

[0307] Incidentally, as shown in Patent Document 1, a flexible tube may be connected to the needle hub. In Patent Document 1, a connecting tube is provided on the base end side of the needle hub, and the flexible tube is connected to the needle hub by inserting the flexible tube into the inner circumference of the connecting tube. In addition, the connecting tube of the needle hub and the flexible tube may be fixed to each other by, for example, bonding with an adhesive.

[0308] However, as a result of investigations by the inventors, a new problem was discovered in that it was difficult to use adhesive to bond the appropriate area between the needle hub and the flexible tube when attempting to bond the needle hub and the flexible tube in the structure described in Patent Document 1. Specifically, there was a risk of improper bonding, such as the adhesive not spreading to the entire area to be bonded, or the adhesive penetrating into the tip side of the flexible tube and blocking the inner cavity of the flexible tube, and a structure that could achieve more appropriate bonding between the needle hub and the flexible tube was desired.

[0309] The problem to be solved by Invention D is to provide a needle assembly with a novel structure that allows the needle hub and the flexible tube to be properly bonded.

[0310] Below, we will describe preferred embodiments for understanding Invention D. However, the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may also be recognized and employed independently to the extent possible, and may also be appropriately combined with any of the components described in other embodiments. Therefore, Invention D is not limited to the embodiments described below, and various other embodiments may be realized.

[0311] The first aspect of Invention D is a needle assembly having a structure in which a needle hub is provided on the base end side of a puncture needle, a connection hole is provided that opens toward the base end side of the needle hub, the end of a flexible tube is inserted into the connection hole, the tube has an inner diameter dimension that is equal to or smaller than the outer diameter dimension of the tube, and the tube is fitted into a fitting portion provided in the connection hole, and an enlarged adhesive portion is provided in the connection hole on the base end side of the fitting portion, and the outer surface of the tube is adhered to the fitting portion.

[0312] With a needle assembly constructed according to this aspect, for example, when an adhesive is injected between the inner circumferential surface of the adhesive portion and the outer circumferential surface of the tube with the tube fitted into the fitting portion distal to the adhesive portion, the injected adhesive is retained between the adhesive portion and the tube, making it difficult for the adhesive to reach the distal end of the tube and preventing the lumen of the needle hub or the lumen of the tube from being narrowed or blocked by the adhesive.

[0313] Furthermore, when the end of the tube is inserted into the connecting hole after adhesive has been applied to at least one of the outer circumferential surface of the tube and the inner circumferential surface of the adhesive portion, the adhesive is less likely to penetrate distally beyond the fitting portion. That is, even if adhesive adheres to the outer circumferential surface of the end of the tube as it passes through the inner periphery of the adhesive portion, the adhesive is scraped off when the tube is fitted into the fitting portion, making it less likely for the adhesive to penetrate between the tube and the fitting portion and remaining between the tube and the adhesive portion. As a result, the adhesive is prevented from entering the lumen of the needle hub at the distal end of the tube, preventing the lumen of the needle hub or the tube from being narrowed or blocked by the adhesive.

[0314] Furthermore, since the tube is fitted into the fitting portion, the end of the tube is positioned relative to the needle hub before being bonded to the adhesive portion, which makes it easier to bond the tube to the needle hub, facilitating manufacturing and stabilizing the quality of the bonded portion.

[0315] A second aspect of Invention D is the needle assembly according to the first aspect of Invention D, wherein a communication passage is provided that connects the inner peripheral region of the adhesive part to external space at a position away from the base end of the adhesive part toward the tip end.

[0316] When injecting adhesive, air present in the inner peripheral region of the adhesive portion needs to be expelled to the outside. However, if adhesive is injected between the adhesive portion and the tube from the proximal end, for example, air may be sealed distally of the adhesive, potentially inhibiting penetration of the adhesive toward the distal end. With the needle assembly constructed according to this aspect, the inner peripheral region of the adhesive portion is connected to the external space through the communication passage at the distal end, so that air is expelled to the external space through the communication passage when adhesive is injected from the proximal end. Therefore, the adhesive can be introduced further distally without being blocked by air, stabilizing the adhesive state and bonding the adhesive portion to the tube over a wide area, thereby achieving high adhesive strength.

[0317] Alternatively, for example, adhesive can be injected between the adhesive part and the tube through the communication passage. In this case, the adhesive is injected from the distal end side, so that air between the adhesive part and the tube is expelled to the outside through the proximal end opening of the connection hole, and the adhesive is introduced to the proximal end side, ensuring a large bonding area between the adhesive part and the tube.

[0318] A third aspect of Invention D is the needle assembly according to the second aspect of Invention D, wherein the communication passages are arranged at a plurality of locations in the circumferential direction of the needle hub.

[0319] With a needle assembly constructed according to this aspect, even if the flexible tube becomes deformed or blocks the opening of the communication passage, the multiple communication passages are arranged at multiple locations around the circumference, so that air can be evacuated or adhesive can be injected through other communication passages that are not blocked by the tube.

[0320] The fourth aspect of Invention D is a needle assembly having a structure in which a needle hub is provided on the base end side of a puncture needle, and a connecting hole that opens toward the base end side of the needle hub is provided, and the end of a flexible tube is inserted into the connecting hole, and the outer surface of the tube is bonded at an adhesive part provided in the connecting hole with an inner diameter dimension that is equal to or greater than the outer diameter dimension of the tube, and communication passages that connect the inner peripheral region of the adhesive part to external space are provided at multiple locations around the circumferential direction of the needle hub at positions away from the base end of the adhesive part toward the tip side.

[0321] In a needle assembly constructed according to this aspect, the inner peripheral region of the adhesive portion is connected to the external space through the communication passage at the distal end, and therefore, when adhesive is injected from the proximal end, air is discharged to the external space through the communication passage. This allows the adhesive to be introduced further to the distal end without being blocked by air, stabilizing the adhesive state and allowing the adhesive portion to adhere to the tube over a wide area, thereby achieving high adhesive strength.

[0322] Alternatively, for example, adhesive may be injected from the distal end side through the communication passage between the adhesive portion and the tube, which allows air between the adhesive portion and the tube to be expelled from the proximal opening of the connection hole to the outside, and allows the adhesive to be introduced to the proximal end side, ensuring a large bonding area between the adhesive portion and the tube.

[0323] Even if the flexible tube is deformed and blocks the opening of the communication passage, since multiple communication passages are arranged at multiple locations in the circumferential direction, air can be discharged or adhesive can be injected through other communication passages that are not blocked by the tube.

[0324] A fifth aspect of Invention D is a needle assembly according to any one of the second to fourth aspects of Invention D, wherein a groove is formed on the inner wall surface of the tip portion of the connecting hole, and the opening of the groove is covered with the tube to form the communicating passage.

[0325] With the needle assembly constructed according to this aspect, a communication passage can be obtained with a simple structure in which a groove is formed on the inner wall surface of the connecting hole, facilitating the manufacture of the needle hub. Furthermore, by covering the opening of the groove with a tube, it is easy to form a communication passage with a smaller cross-sectional area. For example, a communication passage that allows the passage of air but prevents the passage of adhesive can be realized by reducing the cross-sectional area and setting a sufficiently large flow resistance.

[0326] A sixth aspect of Invention D is a needle assembly according to any one of the second to fifth aspects of Invention D, wherein the communicating passage penetrates the peripheral wall of the connecting hole at the adhesive portion.

[0327] With a needle assembly constructed according to this aspect, a communication passage can be easily provided by a hole that penetrates the adhesive part. Furthermore, the cross-sectional shape of the communication passage is less likely to change, preventing unintended narrowing or blockage of the communication passage.

[0328] A seventh aspect of Invention D is a needle assembly according to any one of the second to sixth aspects of Invention D, wherein the communicating passage allows air to pass through but prevents adhesive from passing through.

[0329] A needle assembly constructed in accordance with this aspect can prevent adhesive from leaking to the outside through the communicating passage, and can prevent adhesive from entering the lumen of the needle hub through the communicating passage and narrowing or blocking the lumen of the needle hub or the lumen of the tube.

[0330] An eighth aspect of Invention D is a needle assembly according to any one of the first to seventh aspects of Invention D, wherein the inner periphery of the needle hub is provided with a stepped surface that is superimposed on the tip surface of the tube.

[0331] In the needle assembly constructed according to this aspect, the tube is positioned axially relative to the needle hub by overlapping the distal end surface of the tube with the stepped surface, so that the tube is inserted to an appropriate position in the connecting hole of the needle hub, facilitating appropriate bonding of the tube and the needle hub.

[0332] According to Invention D, in the needle assembly, the needle hub and the flexible tube can be appropriately bonded.

[0333] Hereinafter, an embodiment of Invention D will be described with reference to the drawings.

[0334] Figures 33 to 36 show a needle assembly D-10 with a needle tip protector as a first embodiment of Invention D. The needle assembly D-10 has a structure in which a needle tip protector D-16 is attached to a needle hub D-14 provided on the proximal end of a puncture needle D-12. In the following description, unless otherwise specified, the distal end refers to the left side in Figure 33, which is the side of the needle tip D-20 (described later) of the puncture needle D-12, and the proximal end refers to the right side in Figure 33, which is the rear side in the puncture direction of the needle assembly D-10 with a needle tip protector. Furthermore, as a general rule, the up-down direction refers to the vertical direction in Figure 34, which is the vertical direction, and the left-right direction refers to the horizontal direction in Figure 33. For ease of understanding, in Figures 33 to 37 relating to Invention D, the "D-" has been omitted from each reference symbol "D-○○" (○○ is a number corresponding to the part). In addition, to make it easier to understand that FIGS. 33 to 37 are drawings relating to Invention D, [Invention D] is written in FIGS.

[0335] More specifically, the puncture needle D-12 is made of a metal such as stainless steel, and has a sharp, tapered tip D-20 at one end. A through-hole D-22 is formed at the tip of the puncture needle D-12, allowing blood to easily flow into the lumen of the puncture needle D-12.

[0336] The needle hub D-14 is cylindrical overall and has a lumen D-24 that penetrates in the axial direction, as shown in Figure 35. The base end portion of the puncture needle D-12 is inserted and fixed into the tip portion of the lumen D-24 of the needle hub D-14. This allows the lumen of the puncture needle D-12 to communicate with the lumen D-24 of the needle hub D-14. The needle hub D-14 has a first part D-26 that constitutes the tip portion and a second part D-28 that constitutes the base portion. In this embodiment, the first part D-26 and the second part D-28 are separate parts, but the first part D-26 and the second part D-28 may also be molded integrally.

[0337] The first part D-26 has a substantially cylindrical shape and is made of, for example, a hard synthetic resin. The inner diameter of the tip portion of the first part D-26 is substantially the same as the outer diameter of the puncture needle D-12. The base end portion of the puncture needle D-12 is inserted through an opening on the tip side of the first part D-26, and the puncture needle D-12 is fixed to the needle hub D-14. The puncture needle D-12 may be fixed to the first part D-26 of the needle hub D-14 by non-adhesive means such as press-fitting, or may be adhered using an adhesive.

[0338] The outer peripheral surface of the first part D-26 in the middle part in the needle axis direction is a tapered surface D-32 that gradually increases in diameter toward the tip side, so that the middle part in the needle axis direction of the first part D-26, which has the tapered surface D-32, has a smaller diameter than the tip part and the base end part.

[0339] A locking recess D-36 that opens onto the outer peripheral surface is formed in the first part D-26 at a portion further forward than the tapered surface D-32. The locking recess D-36 is annular and has a substantially constant cross-sectional shape all around. The minimum outer diameter of the first part D-26 at the location where the locking recess D-36 is formed is substantially the same as the minimum outer diameter of the tapered surface D-32.

[0340] The second part D-28 is formed of, for example, a hard synthetic resin, similar to the first part D-26. The second part D-28 has a stepped, generally cylindrical shape overall. A connecting tubular part D-40 having a connecting hole D-38 that opens toward the tip is provided at the tip of the second part D-28. The base end of the first part D-26 is inserted into the connecting hole D-38 of the connecting tubular part D-40 and fixed by adhesive or welding as necessary, thereby fixing the second part D-28 to the first part D-26.

[0341] The base end portion of the second part D-28 is provided with a connecting tubular part D-44 having a connecting hole D-42 that opens toward the base end. As shown in Figures 35 to 37, the connecting tubular part D-44 has a substantially cylindrical shape. The connecting tubular part D-44 forms the peripheral wall of the connecting hole D-42, the inner cavity of the connecting tubular part D-44 forms the connecting hole D-42, and the base end portion of the inner cavity D-24 of the needle hub D-14 is formed by the connecting hole D-42.

[0342] As shown in FIG. 35, the connecting tube portion D-44 has a tapered inner surface D-46 at the base end, which tapers outward toward the base end and gradually becomes thinner toward the base end. Therefore, the connecting hole D-42, which is the inner cavity of the connecting tube portion D-44, has a larger diameter at the opening end, i.e., the base end, which is the end on the opening side, than at the tip end. The connecting tube portion D-44 has a base end portion with the tapered inner surface D-46 as the inner peripheral wall, which is a bonding portion D-48, and a fitting portion D-50 with a smaller diameter than the bonding portion D-48, located distally of the tapered inner surface D-46. The bonding portion D-48 is located proximally of the connecting tube portion D-44 relative to the fitting portion D-50. The maximum inner diameter of the bonding portion D-48 is equal to or greater than the outer diameter of the tube D-84, which will be described later, and is preferably greater than the outer diameter of the tube D-84. The minimum inner diameter of the fitting portion D-50 is equal to or smaller than the outer diameter of the tube D-84, and is preferably smaller than the outer diameter of the tube D-84.

[0343] A stepped surface D-52 is provided on the tip side of the connecting hole D-42. That is, the inner cavity D-24 of the needle hub D-14 has a larger diameter at the connecting hole D-42, and a stepped surface D-52 is formed on the inner peripheral surface of the needle hub D-14 at the boundary between the tip side of the connecting hole D-42 and the connecting hole D-42. The stepped surface D-52 is a substantially annular flat surface extending in the circumferential direction and widening in the axis-perpendicular direction.

[0344] As shown in FIGS. 35 and 37 , the connecting tubular portion D-44 includes a first communication passage D-54 as a radially penetrating communication passage. The first communication passage D-54 penetrates the adhesive portion D-48 and opens to the tapered inner surface D-46. The first communication passage D-54 is connected to the connecting hole D-42 at a position closer to the distal end than the proximal end of the adhesive portion D-48. This first communication passage D-54 connects the inner peripheral region D-55 of the adhesive portion D-48 to the external space at a position closer to the distal end than the proximal end of the adhesive portion D-48. In this embodiment, a pair of first communication passages D-54, 54 are provided on both the upper and lower sides of the connecting tubular portion D-44, extending in the vertical direction. In this embodiment, the first communication passage D-54 is a hole having a circular cross section, but the cross-sectional shape is not limited thereto. The cross-sectional area of ​​the first communication passage D-54 is preferably larger than the cross-sectional area of ​​a second communication passage D-88, which will be described later.

[0345] As shown in Figures 35 to 37, a groove D-56 is formed in the connecting cylindrical portion D-44. The groove D-56 has a substantially semicircular cross section. The groove D-56 is formed in the tip portion of the connecting cylindrical portion D-44, and its base end is located on the tapered inner surface D-46. The groove D-56 is formed at multiple locations in the circumferential direction, and in this embodiment, four grooves D-56, 56, 56, 56 are provided and are disposed substantially evenly in the circumferential direction. The groove D-56 is integrally and continuously provided with a first groove portion D-58 that opens into the inner peripheral surface of the connecting cylindrical portion D-44 and extends in the axial direction, and a second groove portion D-60 that opens into the stepped surface D-52 and extends radially from the tip of the first groove portion D-58 toward the inner circumference.

[0346] The second part D-28 is provided with a pair of engaging arms D-62, 62 located on both the left and right sides of the connecting tubular portion D-40. The engaging arms D-62 are provided so as to protrude from the connecting tubular portion D-44 toward the tip, and reach further toward the tip side than the connecting tubular portion D-40. The engaging arms D-62, 62 are arranged apart on the outside in the left-right direction from the connecting tubular portion D-40, and the connecting portion with the connecting tubular portion D-44 is thin-walled and narrow, allowing elastic deformation in the direction of approaching each other when an external force is applied.

[0347] A hook D-64 is formed at the tip of the engaging arm D-62. The hook D-64 protrudes outward in the left-right direction from the engaging arm D-62. The hooks D-64, 64 provided on the pair of engaging arms D-62, 62 move in directions approaching each other as the engaging arms D-62, 62 elastically deform in the directions approaching each other.

[0348] A needle tip protector D-16 is attached to the needle hub D-14. The needle tip protector D-16 is a component that covers the needle tip D-20 of a used puncture needle D-12 to prevent repeated use of the puncture needle D-12 and prevent the puncture needle D-12 from accidentally puncturing a body, and various conventionally known structures can be employed for the needle tip protector D-16. As shown in Figures 33 to 35, the needle tip protector D-16 of this embodiment has a generally cylindrical shape that extends in the needle axial direction as a whole, and is integrally molded from a hard synthetic resin such as polypropylene, polycarbonate, glycol-modified polyethylene terephthalate, or ABS resin.

[0349] The needle tip protector D-16 has a cylindrical peripheral wall D-66. The tip side of the peripheral wall D-66 is a cylindrical portion D-68 having a cross section of a substantially perfect ring shape. A wing-like portion D-70 is attached to the tip portion of the cylindrical portion D-68. The wing-like portion D-70 is formed of, for example, a soft synthetic resin. The wing-like portion D-70 has a structure in which a plate-shaped wing main body D-72 protrudes tangentially from a cylindrical fitting cylindrical portion D-74. The wing-like portion D-70 is attached to the peripheral wall D-66 of the needle tip protector D-16 by fitting the fitting cylindrical portion D-74 externally onto the tip portion of the cylindrical portion D-68.

[0350] The base end side of the peripheral wall D-66 is an expansion portion D-76 that has a larger diameter than the cylindrical portion D-68 and expands outward, and its shape varies in the needle axial direction. The expansion portion D-76 is approximately elliptical cylindrical, and the width dimension of the outer peripheral surface in the large diameter direction (left-right direction in FIG. 33) is larger than the width dimension of the outer peripheral surface in the small diameter direction (up-down direction in FIG. 34). The left-right outer dimension of the expansion portion D-76 gradually increases from the tip side to the base end side, and the tip of the outer peripheral surface of the expansion portion D-76 smoothly connects to the outer peripheral surface of the cylindrical portion D-68 without any steps or irregularities. Note that the vertical and horizontal outer dimensions of the expansion portion D-76 may be approximately the same. The cross-sectional shape of the outer peripheral surface of the expansion portion D-76 may be circular, rectangular, or the like.

[0351] A through-window D-78 is formed on each of the left and right sides of the widened portion D-76, penetrating the same in the left and right direction. As shown in Figures 33 and 34, the through-window D-78 is shaped like a slit having a predetermined length in the circumferential direction. The circumferential length of the through-window D-78 is greater than the circumferential width of the hook D-64.

[0352] A locking portion D-80 is provided in the center of the expansion portion D-76 in the left-right direction. As shown in Figures 33 and 35, the locking portion D-80 is integrally formed on both the upper and lower base end portions of the expansion portion D-76, and is independent of the wall portion of the expansion portion D-76 in the circumferential direction by forming slit-like cuts on both the left and right sides. As a result, the locking portion D-80 is formed in the shape of a plate that protrudes from the tip portion of the expansion portion D-76 toward the base end, and is allowed to elastically bend and deform in the up-down direction, which is the plate thickness direction.

[0353] The locking portion D-80 is provided with a locking claw D-82 that protrudes inward in the vertical direction. When the needle tip protector D-16 is in a standalone state, the locking claw D-82 has an inner circumferential surface that is inclined inward toward the base end, and the vertical distance between the pair of upper and lower locking claws D-82, 82 decreases toward the base end. The minimum distance between the pair of upper and lower locking claws D-82, 82 is smaller than the outer diameter of the first part D-26 of the needle hub D-14.

[0354] The needle tip protector D-16 is attached to the needle hub D-14 in an externally fitted state, as shown in Figure 35. The hooks D-64, 64 of the needle hub D-14 are inserted into the through-holes D-78, 78 of the needle tip protector D-16, and the hooks D-64, 64 are engaged with the base end edges of the through-holes D-78, 78, thereby connecting the needle tip protector D-16 to the needle hub D-14 in a state in which its movement toward the tip side is restricted. The engaging claw D-82 of the needle tip protector D-16 is elastically pressed against the outer peripheral surface of the first part D-26 of the needle hub D-14.

[0355] The needle tip protector D-16 covers the needle tip D-20 of the used puncture needle D-12. That is, when the puncture needle D-12 is inserted into a blood vessel or the like and then removed from the blood vessel or the like, the engaging arms D-62, 62 are pinched by the user's fingertips, for example, and pushed toward each other in the left-right direction. This causes the hooks D-64, 64 to move inward from the through windows D-78, 78, releasing the engagement between the hooks D-64, 64 and the proximal edges of the through windows D-78, 78. As a result, the needle tip protector D-16 is allowed to move toward the distal end of the needle hub D-14. Then, the user pushes the needle tip protector D-16 toward the tip side relative to the needle hub D-14, in other words, pulls the needle hub D-14 toward the base side relative to the needle tip protector D-16, thereby storing the needle tip D-20 of the puncture needle D-12 within the inner circumference of the needle tip protector D-16.

[0356] The needle tip protector D-16, which has moved to a position covering the needle tip D-20, has its locking claws D-82, 82 enter the locking recess D-36 of the needle hub D-14, and the locking claws D-82, 82 are locked onto the inner surfaces of the distal and proximal ends of the locking recess D-36, thereby restricting its movement toward the distal and proximal ends relative to the needle hub D-14. As a result, the needle tip D-20 of the puncture needle D-12 is housed within the inner periphery of the needle tip protector D-16 without being re-exposed from the needle tip protector D-16.

[0357] A medical tube D-84 is connected to the needle hub D-14. The tube D-84 is made of a flexible material such as synthetic resin and is flexibly deformable. One end of the tube D-84 is fixed to the needle hub D-14. That is, one end of the tube D-84 is inserted into a connecting hole D-42 that opens toward the base end of the needle hub D-14. One end of the tube D-84 is fitted into the fitting portion D-50, and the outer surface of the tube D-84 and the inner surface of the bonding portion D-48 are bonded to each other with adhesive D-86. The distal end of the tube D-84 is axially overlapped with a stepped surface D-52 provided on the inner surface of the needle hub D-14. As a result, the position of the inserted end of the tube D-84 into the connecting hole D-42 is determined in the axial direction by abutting against the stepped surface D-52. In addition, the tip portion of the tube D-84 fitted into the fitting portion D-50 is pushed radially inward and deformed by the reaction force against the fitting portion D-50, and is fitted into the fitting portion D-50 based on the elasticity of the tube D-84.

[0358] When the tube D-84 is fitted into the fitting portion D-50 of the connecting hole D-42, the inner opening of the recessed groove D-56 is covered by the tube D-84. As a result, the recessed groove D-56 forms a second communication passage D-88 as a communication passage extending between the overlapping surfaces of the connecting tubular portion D-44 of the needle hub D-14 and the tube D-84. In this embodiment, the recessed grooves D-56 are arranged at four positions in the circumferential direction, and therefore, the inner opening of each recessed groove D-56 is covered by the tube D-84, so that the second communication passages D-88 are arranged at four positions in the circumferential direction.

[0359] The second communication passage D-88 has a base end opening that opens to the tapered inner surface D-46 and communicates with the inner circumferential region D-55 of the bonded portion D-48, and a tip end opening that opens to the inner circumferential side further distal than the tube D-84 and communicates with the inner cavity D-24 of the needle hub D-14. The inner circumferential region D-55 of the bonded portion D-48 and the external space are mutually communicated through the second communication passage D-88 and the inner cavity D-24 of the needle hub D-14, and the inner circumferential region D-55 of the bonded portion D-48 is open to the external space through the second communication passage D-88.

[0360] The adhesive D-86 is a curing adhesive that can be used to bond the needle hub D-14 and tube D-84, which are medical instruments. For example, in addition to ultraviolet-curing adhesives that harden when exposed to ultraviolet light, cyanoacrylate adhesives, epoxy resin adhesives, hot-melt adhesives, acrylic adhesives, etc. are suitably used.

[0361] The adhesive D-86 is injected into the connecting hole D-42 of the needle hub D-14 into which the end of the tube D-84 is inserted. The adhesive D-86 may be injected between the connecting tubular portion D-44 of the needle hub D-14 and the tube D-84 from the proximal opening of the connecting hole D-42, but in this embodiment, it is injected between the connecting tubular portion D-44 of the needle hub D-14 and the tube D-84 through the first communication passage D-54. The adhesive portion D-48, which is the opening on the proximal side of the connecting hole D-42, has an inner diameter larger than that of the fitting portion D-50, which is the distal end portion, and the gap between the inner circumferential surface of the connecting tubular portion D-44 and the outer circumferential surface of the tube D-84 at the adhesive portion D-48 is larger. This allows a predetermined amount of adhesive D-86 to accumulate and be retained between the connecting tubular portion D-44 and the tube D-84. When injecting the adhesive D-86, it is desirable to hold the needle hub D-14 so that the tip side, which is the needle tip D-20 side, faces vertically downward, and to cover the base end opening of the connection hole D-42 with an appropriate lid member, etc. This makes it less likely that the adhesive D-86 injected from the first communication passage D-54 into the connection hole D-42 will spill out from the base end opening of the connection hole D-42.

[0362] When the adhesive D-86 is injected through the first communication passage D-54 toward the distal end of the first communication passage D-54, the air in the connection hole D-42 is discharged into the lumen D-24 of the needle hub D-14 through the second communication passage D-88, which is located further distal than the first communication passage D-54. This prevents the air in the connection hole D-42 from obstructing the progress of the adhesive D-86 toward the distal end, and allows the needle hub D-14 and the tube D-84 to be bonded over a wider area.

[0363] The second communication passage D-88 is provided partially in the circumferential direction and has a sufficiently small cross-sectional area, thereby allowing the passage of air but preventing the passage of adhesive D-86. Therefore, the adhesive D-86 injected into the connecting hole D-42 does not enter the lumen D-24 of the needle hub D-14 through the second communication passage D-88, and the lumen D-24 of the needle hub D-14 and the distal opening of the tube D-84 are not blocked entirely or partially by the adhesive D-86. Although there is no problem if the adhesive D-86 penetrates partway into the second communication passage D-88, it is desirable that the adhesive D-86 does not pass through the second communication passage D-88 and reach the lumen D-24 of the needle hub D-14.

[0364] The second communication passage D-88 is formed by covering with the tube D-84 the opening of the recessed groove D-56 formed on the inner surface of the needle hub D-14, and therefore the cross-sectional area of ​​the passage can be made smaller than that of the first communication passage D-54, which is formed by a hole penetrating the hard needle hub D-14. Therefore, by making the opening area of ​​the second communication passage D-88 toward the base end sufficiently small, the flow resistance of the second communication passage D-88 can be set large enough to prevent the adhesive D-86 from passing through the second communication passage D-88.

[0365] As a result, the adhesive area between the inner surface of the connecting hole D-42 in the needle hub D-14 and the tube D-84 by the adhesive D-86 is appropriately controlled and provided, thereby ensuring a sufficiently strong fixing strength between the needle hub D-14 and the tube D-84 and preventing the adhesive D-86 from seeping in and causing narrowing or blockage of the lumen D-24 of the needle hub D-14 or the lumen of the tube D-84.

[0366] The flexible tube D-84 may not be inserted into the needle hub D-14 in a straight state as shown in Figure 35. For example, if the tube D-84 is curved upward toward the base end, the upper second communication passage D-88 may be covered and blocked by the tube D-84. However, since the needle hub D-14 has multiple second communication passages D-88 arranged at different circumferential positions, even if one second communication passage D-88 is blocked, the other second communication passages D-88 remain in communication, allowing air to be vented through the second communication passages D-88. Similarly, since multiple first communication passages D-54 are arranged at different circumferential positions, simultaneous blocking of all first communication passages D-54 is prevented, allowing smooth injection of the adhesive D-86.

[0367] The adhesive D-86 is injected into the connecting hole D-42 of the needle hub D-14 with the end of the tube D-84 inserted in the connecting hole D-42, for example, but the tube D-84 may be inserted into the connecting hole D-42 after the adhesive D-86 has been applied to at least one of the outer circumferential surface of the tube D-84 and the inner circumferential surface of the connecting hole D-42 (adhesive portion D-48). In this case, when the tip portion of the tube D-84 is fitted into the fitting portion D-50 of the connecting hole D-42, the outer circumferential surface of the tube D-84 is pressed against the inner circumferential surface of the fitting portion D-50, so that the adhesive D-86 adhering to the outer circumferential surface of the tube D-84 is scraped off by the fitting portion D-50. Therefore, for example, even if the adhesive D-86 adheres to the outer peripheral surface of the tip portion of the tube D-84 when the tip portion of the tube D-84 passes through the inner circumference of the adhesive portion D-48, the adhesive D-86 is unlikely to enter between the tube D-84 and the fitting portion D-50. Therefore, the adhesive D-86 can be prevented from entering the lumen D-24 of the needle hub D-14 at the tip side of the tube D-84, and the lumen D-24 of the needle hub D-14 and the lumen of the tube D-84 can be prevented from being narrowed or blocked by the adhesive D-86.

[0368] Although the embodiments of Invention D have been described above in detail, Invention D is not limited to those specific descriptions. For example, in the above embodiment, an example was shown in which a hole-shaped first communication passage D-54 is provided on the base end side of the connecting tubular portion D-44 and a second communication passage D-88 formed by a recessed groove D-56 is provided on the tip side of the connecting tubular portion D-44, but the communication passage may be formed of only either the first communication passage D-54 or the second communication passage D-88. Also, a hole-shaped communication passage may be provided in the tip portion of the adhesive portion D-48.

[0369] In the above embodiment, the configuration for allowing air to pass through the second communication passage D-88 and preventing the adhesive D-86 from passing through is exemplified by reducing the cross-sectional area of ​​the second communication passage D-88 to increase the flow resistance. However, the configuration for allowing air to pass through and preventing the adhesive D-86 from passing through can also be realized by, for example, providing a filter in the second communication passage D-88 that allows air to pass through and prevents the adhesive D-86 from passing through.

[0370] In the above-described embodiment, the opening on the tip side of the second communication passage D-88 communicates with the external space via the lumen D-24 of the needle hub D-14, but it may also communicate directly with the external space without going through the lumen D-24 of the needle hub D-14. Specifically, for example, instead of the second groove portion D-60 extending radially inward from the tip end of the first groove portion D-58, a hole extending radially outward from the tip end of the first groove portion D-58 may be provided, thereby making it possible to directly communicate the second communication passage with the external space.

[0371] In the above embodiment, an example has been shown in which the adhesive D-86 is introduced into the connection hole D-42 through the first communication passage D-54, and the air in the connection hole D-42 is discharged through the second communication passage D-88. However, for example, the adhesive D-86 may be introduced into the connection hole D-42 through the second communication passage D-88, and the base end openings of the first communication passage D-54 and the connection hole D-42 may serve as vents for discharging air. When the first communication passage D-54 is used as a vent for discharging air in the connection hole D-42, it is desirable that the first communication passage D-54, like the second communication passage D-88 in the above embodiment, allows the passage of air but prevents the passage of the adhesive D-86.

[0372] Alternatively, the adhesive D-86 may be introduced into the connection hole D-42 from the base-end opening of the connection hole D-42, and both the first communication passage D-54 and the second communication passage D-88 may serve as vents for discharging air from the connection hole D-42. In this case, when the adhesive D-86 is injected from the base-end opening of the connection hole D-42, the air in the connection hole D-42 is first discharged to the outside through both the first communication passage D-54 and the second communication passage D-88. As a result, the adhesive D-86 does not remain at the opening of the connection hole D-42 but penetrates into the interior, bonding the inner circumferential surface of the connecting tubular portion D-44 and the outer circumferential surface of the tube D-84 over a wide area. Next, when the adhesive D-86 fills up to a position where it blocks the inner opening of the first communication passage D-54, the air in the connection hole D-42 is no longer discharged to the outside through the first communication passage D-54. Here, because the second communication passage D-88 is located closer to the tip than the first communication passage D-54, air continues to be discharged into the lumen D-24 of the needle hub D-14 through the second communication passage D-88. Therefore, even if the first communication passage D-54 is blocked by the adhesive D-86, the air in the connection hole D-42 does not hinder the advance of the adhesive D-86 toward the tip, and the needle hub D-14 and the tube D-84 are bonded over a wider area.

[0373] The number, arrangement, shape, size, etc. of the communication passages are not particularly limited. For example, when the communication passages are used to introduce adhesive D-86, it is desirable that the cross-sectional area of ​​the passage be relatively large, as in the first communication passage D-54 of the above embodiment, so that the adhesive D-86 can be introduced smoothly. Furthermore, when the communication passages are used to exhaust air, it is desirable that the cross-sectional area be relatively small, as in the second communication passage D-88 of the above embodiment, so that the adhesive D-86 cannot easily penetrate.

[0374] In the above embodiment, the inner peripheral surface of the adhesive portion D-48 is a tapered inner surface D-46, which forms a space for holding the adhesive D-86 between the adhesive portion D-48 and the tube D-84, but the structure for forming the space between the adhesive portion D-48 and the tube D-84 is not limited to the tapered inner surface D-46. Specifically, for example, a step may be provided on the inner peripheral surface of the connecting tubular portion D-44, and the inner diameter dimension of the adhesive portion D-48 may be made larger than the outer diameter dimension of the tube D-84, thereby forming a space for holding the adhesive D-86 between the adhesive portion D-48 and the tube D-84.

[0375] The needle tip protector D-16 is not essential and can be omitted. Also, a needle tip protector having a structure or material different from that of the needle tip protector D-16 of the above embodiment may be used. [Explanation of symbols]

[0376] A-10 Needle tip protector A-12 Needle assembly A-14 Puncture needle A-16 Puncture needle A-18 Needle Hub A-20 needle tip A-22 Through hole A-24 Needle support part A-26 Protector connection part A-28 Positioning protrusion A-30 Tapered surface A-32 Small diameter cylinder part A-34 Locking recess A-36 Large diameter support part A-38 Base end control surface A-40 Tip side restriction surface A-42 Connecting cylinder part A-44 Connecting tube A-46 Recess A-47 External conduit A-48 Fluid Flow Path A-50 Engagement Arm A-52 Hook A-54 Surrounding wall A-56 Inner hole A-57 Proximal opening A-58 Cylindrical section A-60 Expansion section A-62 Narrow section A-64 Wide section A-66 interior space A-68 Through window A-70 Thick wall part A-71 Bridge section A-72 Recess A-74 dent A-76 Step surface A-78 Locking piece (flexible piece) A-80 Locking Claw A-82 Proximal end face A-82a Small wall section A-82b Slope A-84 Split type A-86 Split type A-88 mold A-90 Parting surface A-92 Parting line A-94 Cavity A-96 Injection gate A-98 Injection gate remains A-100 Protruding pin A-102 Protruding pin mark A-104 Airfoil A-106 Fitting cylinder A-108 Connection section A-110 wing body A-112 Contact part A-120 Needle Tip Protector A-122 Needle assembly A-130 mold A-132 cavity A-134 Injection gate A-140 Needle Tip Protector A-142 Recess A-150 Needle Tip Protector A-160 Needle Tip Protector B-10 Puncture needle B-12 Needle assembly B-14 Needle Tip Protector B-16 Puncture needle B-18 needle hub B-20 Needle tip B-22 Through hole B-24 Needle support part B-26 Protector connection part B-30 Tapered surface B-32 Small diameter cylinder part B-34 Recess B-36 Convex B-38 Proximal regulation surface B-40 Tip side regulation surface B-42 Connecting cylinder part B-44 connecting tube B-46 Recess B-48 connection hole B-50 bottom B-52 Opening expansion section B-54 Reinforcement B-56 Connection Port B-58 Tapered outer surface B-60 External conduit B-62 Fluid Flow Path B-64 Arm B-66 Hook B-68 Surrounding wall B-70 Inner hole B-72 Cylindrical section B-74 Expansion section B-76 Narrow section B-78 wide section B-80 interior space B-82 Through window B-84 Stepped surface B-86 Projection piece B-88 Claw part B-90 Proximal end face B-90a vertical plane B-90b Slope B-92 wing B-94 Fitting cylinder B-96 Connection section B-98 wing body B-100 Puncture needle B-102 Needle Hub B-103 Needle support part B-104 Protector connection part B-106 Connection hole B-108 Bottom B-110 Opening expansion section B-112 Reinforcement B-114 Connection port B-116 Arm C-10 Needle Tip Protector C-12 Needle assembly C-14 Indwelling needle C-16 Puncture needle C-18 needle hub C-20 needle tip C-22 Through hole C-24 Needle support part C-26 Protector connection part C-28 Positioning protrusion C-30 Tapered surface C-32 Small diameter cylinder part C-34 Locking recess C-36 Large diameter support part C-38 Proximal regulation surface C-40 Tip side regulation surface C-42 Connecting cylinder part C-44 Connecting tube C-46 Recess C-47 External conduit C-48 Fluid Flow Path C-50 Engagement arm C-52 Hook C-54 Surrounding wall C-56 Inner hole C-58 Cylindrical section C-60 expansion section C-62 Narrow section C-64 Wide section C-66 interior space C-68 Through window C-70 recess C-74 Stepped surface C-76 Locking piece C-78 Locking Claw C-80 Proximal end face C-80a vertical plane C-80b Slope C-82 wing C-84 Fitting cylinder part C-86 Connection section C-88 wing body C-90 Contact part C-92 Parting Line C-94 Gate Remains C-96 Parting Line C-98 Gate Remains C-140 Deformation limiting section C-142 Protrusion D-10 Needle assembly with needle tip protector (needle assembly) D-12 Puncture needle D-14 Needle Hub D-16 Needle Tip Protector D-20 Needle tip D-22 Through hole D-24 Lumen D-26 1st part D-28 2nd part D-32 Tapered surface D-36 Locking recess D-38 Connection hole D-40 Connecting cylinder part D-42 Connection hole D-44 Connecting tube D-46 Tapered inner surface D-48 Adhesive part D-50 fitting part D-52 Step surface D-54 1st communication passage (communication passage) D-55 Inner area D-56 Concave groove D-58 1st groove D-60 2nd groove D-62 Engagement arm D-64 Hook D-66 Surrounding wall D-68 Cylindrical part D-70 wing D-72 wing body D-74 Fitting cylinder D-76 Expansion section D-78 Through window D-80 Locking part D-82 Locking Claw D-84 Tube D-86 Adhesive D-88 2nd communication passage (communication passage)

Claims

1. A needle tip protector made of resin having a peripheral wall that covers the tip of the puncture needle by moving in the needle axis direction relative to the puncture needle, The peripheral wall has a cylindrical portion at a tip end thereof, a thick-walled portion having a portion thicker than the cylindrical portion is provided on the peripheral wall on the base end side of the cylindrical portion, and a trace of a resin material injection gate used during molding is provided on an outer peripheral surface of the thick-walled portion; The outer dimension of the peripheral wall in the axis-perpendicular direction at least at the base end portion is varied in the circumferential direction, The wide portion has a large outer dimension and is provided with an engaging portion that engages with a needle hub fixed to the base end of the puncture needle, and an engaging piece that is engaged with the needle hub to prevent the needle tip from re-extruding, The injection gate trace is provided in the narrow portion having a small outer dimension, The injection gate trace is provided at a position circumferentially spaced apart from the engaging portion and the locking piece, The needle tip protector has an inner peripheral surface corresponding to the injection gate mark that has a recessed portion toward the injection gate mark.

2. A needle tip protector made of resin having a peripheral wall that covers the tip of the puncture needle by moving in the needle axis direction relative to the puncture needle, The peripheral wall has a cylindrical portion at a tip end thereof, The peripheral wall is provided with an expanded portion on the base end side of the cylindrical portion, the expanded portion having an increased outer dimension including a portion with a wall thickness greater than that of the cylindrical portion, the outer surface of the peripheral wall does not have a parting line formed by an axial punching die and extending in the axial direction, but has a parting line extending in the circumferential direction along the boundary between the cylindrical portion and the expanded portion, The expanded portion is located away from the parting line toward the axial base end, and a trace of a resin material injection gate used during molding is provided on the axial base end side of the expanded portion.

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