Catheter

Abstract

A catheter (10) comprises an extension part (38) in which the distal end is positioned closer to the distal end side than an insertion part (34) of an opening member (18). During a process in which the opening member (18) moves from an initial position to a movement completion position in a catheter hub (14), the extension part (38) opens a valve (16) when the opening member (18) reaches an intermediate position between the initial position and the movement completion position. When the opening member (18) moves further in the distal end direction, at least a portion of the extension part (38) is displaced relative to the opening member (18), whereby the opening member (18) is able to reach the movement completion position.

Description

catheter

[0001] The present disclosure relates to catheters.

[0002] Indwelling needles with hemostatic valves are well known (see, for example, Japanese Patent Application Laid-Open No. 2017-6726). This type of indwelling needle includes a catheter and an inner needle. The catheter has a catheter body and a catheter hub, and a hemostatic valve is disposed in the lumen of the catheter hub. After the tip of the indwelling needle is inserted into a blood vessel, the inner needle is removed from the catheter. When the male connector of an infusion set is then inserted into the base end of the catheter hub, an opening member, which is a movable part disposed in the lumen of the catheter hub, moves toward the tip, opening the hemostatic valve. This allows blood to flow into the lumen of the catheter hub. As blood flows into the lumen of the catheter hub, air is expelled from the lumen of the catheter hub.

[0003] Japanese Patent Application Laid-Open No. 2017-6726

[0004] In order to expel air from the lumen of the catheter hub, it is necessary to ensure an air evacuation path. However, once the male connector is connected (mated) to the catheter hub, the air evacuation path is blocked, preventing air from escaping. Designing such an appropriate dimensional relationship between components is not easy because it requires high dimensional accuracy. It is possible to advance the timing of the hemostatic valve opening by extending the overall length of the opening member. However, simply lengthening the opening member may cause the opening member to come into contact with an obstacle within the catheter hub before the male connector is fully connected to the catheter hub, preventing proper connection of the male connector to the catheter hub.

[0005] The present disclosure aims to solve the above-mentioned problems.

[0006] (1) An aspect of the present disclosure is a catheter comprising: a catheter body; a catheter hub connected to a proximal end of the catheter body; a valve arranged to separate a hub lumen, which is a hollow portion of the catheter hub, into a distal region and a proximal region; and an opening member arranged in the hub lumen and having an insertion portion facing the valve, the opening member opening the valve by the insertion portion as the opening member moves distally relative to the catheter hub, so as to enable fluid communication between the distal region and the proximal region in the hub lumen; the opening member being supported by the insertion portion of the opening member, and having a tip positioned distally of the insertion portion. the opening member is subjected to a pushing force in the distal direction, and in the process of the opening member moving from an initial position to a movement completion position relative to the catheter hub, the opening member receives a pushing force in the distal direction, and when the opening member reaches an intermediate position between the initial position and the movement completion position, the extension portion opens the valve; and when the opening member moves further from the intermediate position toward the distal end, the extension portion receives a resistance force of a predetermined level or more, and as a result, at least a portion of the extension portion is displaced relative to the opening member, allowing the opening member to reach the movement completion position.

[0007] With this configuration, compared to conventional valved catheters, the timing of valve opening can be accelerated during the process of connecting the male connector to the catheter hub. This allows blood to flow into the catheter hub quickly and air to be expelled from the catheter hub after the opening member begins to move. Furthermore, because the extension portion can be displaced relative to the opening member when it receives a resistance force greater than a predetermined level, movement of the opening member to the movement completion position is not hindered. This allows the male connector to be connected to the catheter hub without any problems.

[0008] (2) In the catheter described in the above item (1), when the opening member moves further from the intermediate position toward the distal end, the extension portion may abut against an abutment portion provided in the hub lumen and receive the resistance force from the abutment portion.

[0009] According to this configuration, the extension portion can be displaced relative to the opening member with a simple configuration.

[0010] (3) In the catheter described in item (2) above, the extension portion may be movable relative to the opening member in the axial direction of the catheter hub, and the extension portion may move relative to the opening member in the proximal direction when it receives the resistance force from the abutment portion.

[0011] According to this configuration, the extension portion can be displaced relative to the opening member with a simple configuration.

[0012] (4) In the catheter described in item (3) above, the extension portion may have a valve pressing portion that presses the valve to open when the opening member reaches the intermediate position, and the valve pressing portion may be inserted into the insertion portion and protrude from the insertion portion toward the distal end when the opening member is located at the initial position.

[0013] According to this configuration, the extension portion can be well supported by the insertion portion of the opening member.

[0014] (5) In the catheter described in item (4) above, the insertion portion of the opening member has a side hole and a locking portion that is locked to the opening member, and the locking portion may protrude outward from the insertion portion through the side hole and engage with the outer surface of the insertion portion.

[0015] According to this configuration, the locking portion can be securely locked to the insertion portion.

[0016] (6) In the catheter according to the above item (4) or (5), the valve pressing portion may be a hollow cylindrical body.

[0017] With this configuration, it is easy to ensure the rigidity required to open the valve, and good liquid permeability can be ensured.

[0018] (7) In the catheter described in item (3) above, the extension portion has a valve pressing portion that presses the valve to open it when the opening member reaches the intermediate position, and a locking portion that is locked to the opening member, and when the opening member moves further from the intermediate position toward the tip, the resistance force that the extension portion receives from the abutting portion may cause the locking portion to release from the opening member.

[0019] With this configuration, when the locking portion is locked to the opening member, relative movement of the extension portion with respect to the opening member is prevented, so the valve can be opened by the valve pressing portion moving in the distal direction. Furthermore, after the valve is opened, the locking portion is released from the opening member, so the extension portion can be displaced in the proximal direction relative to the opening member.

[0020] (8) In the catheter described in item (7) above, a locking protrusion that can abut against the tip of the insertion section is provided at the tip of the extension section, and the locking protrusion may determine the maximum relative displacement of the extension section toward the base end with respect to the opening member.

[0021] According to this configuration, when the extension portion is displaced relative to the insertion portion in the proximal direction, the extension portion can be prevented from coming off the insertion portion.

[0022] (9) In the catheter described in item (7) above, the locking portion may have an arm extending from the valve pressing portion, a first locking claw protruding from the arm, and a second locking claw protruding from the arm, wherein the first locking claw is locked to the opening member when the opening member is located in the initial position, and the second locking claw is positioned further toward the distal end than the first locking claw and defines the maximum relative displacement of the extension portion toward the proximal end with respect to the opening member.

[0023] According to this configuration, when the extension portion is displaced relative to the insertion portion in the proximal direction, the extension portion can be prevented from coming off the insertion portion.

[0024] (10) In the catheter described in item (1) above, when the opening member is located in the initial position, the extension portion may cover the tip of the insertion portion, and when the opening member moves further from the intermediate position toward the tip, the extension portion may receive the resistance force from the inner surface of the valve and change to a form that exposes the tip of the insertion portion.

[0025] According to this configuration, the opening timing of the valve can be advanced by using an extension portion with a simple configuration.

[0026] (11) In the catheter described in item (1) above, the extension portion may be movable relative to the opening member in the axial direction of the catheter hub, and when the opening member is located in the initial position, the extension portion covers the tip end of the insertion portion, and when the opening member moves further from the intermediate position toward the tip end, the extension portion may abut against an abutment portion provided in the hub lumen and receive the resistance force from the abutment portion, thereby moving relative to the opening member in the proximal direction.

[0027] According to this configuration, the opening timing of the valve can be advanced by using an extension portion with a simple configuration.

[0028] (12) In the catheter described in the above item (11), the insertion section may include a tubular main body having an inner cavity that is a fluid passage, and a rib that protrudes from the outer peripheral surface of the tubular main body and extends in the axial direction, and the extension section may be formed with a slit that allows the rib to enter when the opening member moves further from the intermediate position toward the tip.

[0029] With this configuration, the rib does not hinder the relative movement of the extension portion, allowing the extension portion to perform its function well.

[0030] The catheter of the present disclosure allows the valve to open earlier during the process of connecting the male connector to the catheter hub, compared to conventional valved catheters. This allows blood to flow into the catheter hub quickly and air to be expelled from the catheter hub after the opening member begins to move. Furthermore, because the extension portion can be displaced relative to the opening member when it receives a resistance force greater than a predetermined level, movement of the opening member to the movement completion position is not hindered. This allows the male connector to be connected to the catheter hub without any problems.

[0031] FIG. 1 is a cross-sectional view of a catheter according to an embodiment of the present disclosure. FIG. 2A is a cross-sectional view taken along line IIA-IIA in FIG. 1. FIG. 2B is a cross-sectional view taken along line IIB-IIB in FIG. 5. FIG. 3 is a perspective view of an extension portion. FIG. 4 is a cross-sectional view of a catheter when the opening member is located at an intermediate position. FIG. 5 is a cross-sectional view of a catheter when the opening member is located at a movement completion position. FIG. 6 is a perspective view of an extension portion according to a first modified example. FIG. 7A is a cross-sectional view showing the relationship between the opening member and the extension portion when the opening member is located at an initial position. FIG. 7B is a cross-sectional view showing the relationship between the opening member and the extension portion when the opening member is located at a movement completion position. FIG. 8 is a perspective view of an extension portion according to a second modified example. FIG. 9A is a cross-sectional view showing the relationship between the opening member and the extension portion when the opening member is located at the initial position. FIG. 9B is a cross-sectional view showing the relationship between the opening member and the extension portion when the opening member is located at a movement completion position. FIG. 10A is a first state diagram of an extension portion according to a third modified example. FIG. 10B is a second state diagram of an extension portion according to the third modified example. Fig. 10C is a third state diagram for the extension portion according to the third modified example. Fig. 11 is a perspective view of the extension portion according to the third modified example. Fig. 12A is a first state diagram for the extension portion according to the fourth modified example. Fig. 12B is a second state diagram for the extension portion according to the fourth modified example. Fig. 12C is a third state diagram for the extension portion according to the fourth modified example. Fig. 13 is a perspective view of the extension portion according to the fourth modified example.

[0032] The catheter 10 according to this embodiment comprises a catheter body 12, a catheter hub 14, a valve 16, and an opening member 18. The catheter 10 is combined with a needle member 102 in an initial state. The catheter 10 and the needle member 102 constitute a catheter assembly 100. The needle member 102 comprises an inner needle 104 having a sharp tip, and a needle hub 106 connected to the proximal end of the inner needle 104. In the initial state of the catheter assembly 100, the inner needle 104 is inserted into the catheter body 12 and the needle hub 106, and the tip end of the needle hub 106 is detachably connected to the proximal end of the catheter hub 14.

[0033] The catheter 10 may be configured as, for example, a peripheral venous catheter. The catheter 10 may also be a catheter longer than a peripheral venous catheter (for example, a central venous catheter, PICC, midline catheter, etc.). The catheter 10 is not limited to a venous catheter, and may also be an arterial catheter such as a peripheral arterial catheter.

[0034] The catheter body 12 is a flexible tubular member having a lumen formed therein. The catheter 10 may be made of, for example, a transparent resin material.

[0035] The catheter hub 14 is connected to the proximal end of the catheter body 12. The catheter hub 14 may be made of, for example, a transparent resin material. The catheter hub 14 is hollow and tubular, having a lumen 15. Hereinafter, the lumen 15 of the catheter hub 14 will also be referred to as the "hub lumen 15." The direction along the axis Ax of the catheter hub 14 will be referred to as the "axial direction."

[0036] The proximal end of the catheter body 12 is inserted into the distal end of the catheter hub 14. A crimping pin 20 is disposed in the hub lumen 15. The crimping pin 20 is inserted into a small-diameter section 140 provided at the distal end of the catheter hub 14. The proximal end of the catheter body 12 is clamped between the inner circumferential surface of the small-diameter section 140 of the catheter hub 14 and the crimping pin 20, thereby fixing the catheter body 12 to the catheter hub 14. A hollow fixing member 22 is fixed to the proximal end of the hub lumen 15. If the fixing member 22 is considered to be part of the catheter hub 14, the fixing member 22 can also be referred to as the proximal end of the catheter hub 14. For this reason, in the following description, the fixing member 22 may also be referred to as the "proximal end of the catheter hub 14."

[0037] The valve 16 is disposed in the hub lumen 15. The valve 16 separates the hub lumen 15 into a distal region and a proximal region. The valve 16 is a hemostatic valve that prevents blood from leaking from the proximal opening of the catheter hub 14 after the inner needle 104 has been removed from the catheter body 12 and before the male connector 48 (see FIG. 4 ) is connected to the catheter hub 14. The valve 16 is hollow. A valve space is formed inside the valve 16.

[0038] The valve 16 is configured as a duckbill valve. Specifically, the valve 16 has an annular portion 24 and a valve body 26. The annular portion 24 protrudes radially outward from the base end of the valve body 26. In order to secure the valve 16 to the inner periphery of the catheter hub 14, a stepped portion 142 and a locking protrusion 144 are provided on the inner periphery of the catheter hub 14. The outer periphery of the annular portion 24 is sandwiched between the stepped portion 142 and the locking protrusion 144, thereby securing the valve 16 to the inner periphery of the catheter hub 14. The valve 16 is configured from an elastic material such as an elastomer material.

[0039] The valve body 26 protrudes distally from the annular portion 24. The valve body 26 has a pair of bill portions 260 divided by a slit 27. The pair of bill portions 260 come into close contact with each other, closing the valve 16. The pair of bill portions 260 move away from each other, creating a gap, opening the valve 16. The pair of bill portions 260 have a pair of inclined portions 261 that approach each other distally. In the initial state of the catheter assembly 100, the inner needle 104 penetrates the valve body 26, and the inner needle 104 is sandwiched between the pair of bill portions 260.

[0040] The opening member 18 is disposed in the lumen (hub lumen 15) of the catheter hub 14. The opening member 18 is a member for opening the valve 16 when the male connector 48 is connected to the catheter hub 14. The opening member 18 is movable relative to the catheter hub 14 in the axial direction within the hub lumen 15. Specifically, the opening member 18 is movable from the initial position shown in Figure 1 to the movement completion position shown in Figure 5.

[0041] 1 , the opening member 18 has a body 30, a pair of legs 32, and an insertion portion 34. The body 30 is formed in a cylindrical shape and is supported by the inner circumferential portion of the catheter hub 14. The pair of legs 32 extend in the proximal direction from the proximal end of the body 30. The proximal end surfaces of the pair of legs 32 are engaged with the fixing member 22, thereby preventing the opening member 18 from slipping out in the proximal direction from the catheter hub 14. The proximal end surfaces of the pair of legs 32 protrude slightly inward from the inner circumferential surface of the fixing member 22. Therefore, a step is formed between the inner surfaces of the pair of legs 32 and the inner circumferential surface of the fixing member 22.

[0042] The insertion portion 34 has a smaller diameter than the trunk portion 30 and protrudes distally from the tip of the trunk portion 30. The insertion portion 34 is hollow and has an inner cavity that communicates with the inner cavity of the trunk portion 30. The insertion portion 34 includes a cylindrical main body portion 341 having an inner cavity that serves as a fluid passage, and a pair of ribs 342 that protrude from the outer peripheral surface of the cylindrical main body portion 341 and extend in the axial direction. The pair of ribs 342 are located on opposite sides of the outer peripheral surface of the cylindrical main body portion 341.

[0043] As the opening member 18 moves distally relative to the catheter hub 14, the insertion portion 34 opens the valve 16 to allow fluid communication between the distal and proximal regions of the hub lumen 15. As shown in FIG. 2A , the insertion portion 34 has a pair of side holes 36 facing each other. Each side hole 36 is a hole that penetrates the peripheral wall of the insertion portion 34 in the thickness direction. As shown in FIG. 1 , each side hole 36 is located at the same circumferential position as the slit 27 of the valve body 26. With this configuration, when the valve body 26 is opened, the slit 27 and each side hole 36 face each other, so the side holes 36 are not blocked by the bill portion 260. A tapered portion 340 that narrows in diameter toward the distal end is provided on the outer peripheral surface of the distal end of the insertion portion 34.

[0044] As shown in Figure 1, the catheter 10 further includes an extension portion 38. The extension portion 38 is supported by the insertion portion 34 of the opening member 18. The tip of the extension portion 38 is located distally of the insertion portion 34. The extension portion 38 is movable relative to the opening member 18. In this embodiment, the extension portion 38 is movable in the axial direction of the catheter hub 14 relative to the opening member 18.

[0045] As shown in FIG. 3 , the extension portion 38 has a valve pressing portion 40 and at least one locking portion 42. In this embodiment, the valve pressing portion 40 is a hollow tubular body. As shown in FIG. 2A , the valve pressing portion 40 is inserted into the insertion portion 34. When the opening member 18 is in the initial position, the valve pressing portion 40 protrudes distally from the insertion portion 34. As shown in FIG. 1 , when the opening member 18 is in the initial position, the distal end of the valve pressing portion 40 does not contact the valve body 26. That is, there is a slight gap between the distal end of the valve pressing portion 40 and the valve body 26. In the initial state of the catheter assembly 100, the inner needle 104 is inserted into the valve pressing portion 40. Note that the valve pressing portion 40 does not necessarily have to be a hollow tubular body as long as it has a shape that allows the insertion of the inner needle 104. Therefore, the valve pressing portion 40 may have, for example, an arc-shaped cross section and extend in the axial direction.

[0046] 2A , when the opening member 18 is in the initial position, the locking portion 42 is locked to the opening member 18. Specifically, the locking portion 42 protrudes outward from the insertion portion 34 through the side hole 36 and engages with the outer surface of the insertion portion 34. In this embodiment, the extension portion 38 has a pair of locking portions 42. The pair of locking portions 42 protrude from positions on opposite sides of the valve pressing portion 40.

[0047] Each locking portion 42 has an arm 44 and a locking claw 46. The arm 44 extends distally from the valve pressing portion 40. The base end of the arm 44 is a fixed end connected to the valve pressing portion 40. The base end of the arm 44 is connected to the base end of the valve pressing portion 40. The tip end of the arm 44 is a free end. Therefore, the arm 44 is elastically deformable in a direction perpendicular to the axis Ax. The length of the arm 44 in the axial direction is shorter than the length of the valve pressing portion 40. Note that the base end of the arm 44 is not limited to the base end of the valve pressing portion 40, and may be located at a position where the tip of the extension portion 38 is located distally of the insertion portion 34 when the opening member 18 is located in the initial position.

[0048] The locking claw 46 protrudes from the arm 44 toward the valve pressing portion 40. When the opening member 18 is located in the initial position, the locking claw 46 engages with a tapered portion 340 provided at the tip end of the insertion portion 34.

[0049] The catheter assembly 100 including the catheter 10 shown in FIG. 1 is used as follows.

[0050] The inner needle 104 of the catheter assembly 100 and the distal end of the catheter 10 are inserted into a living body. After the distal ends of the inner needle 104 and the catheter 10 have punctured a blood vessel, the needle member 102 is removed from the catheter 10. At this time, the inner needle 104 is removed from the catheter body 12, but the valve 16 prevents blood from flowing into the hub lumen 15.

[0051] 4 , the male connector 48 of the infusion line is inserted into the proximal end (specifically, the fixing member 22) of the catheter hub 14. As the male connector 48 is inserted into the catheter hub 14, the distal surface of the male connector 48 pushes the opening member 18 in the distal direction, causing the opening member 18 to advance within the catheter hub 14. In other words, the opening member 18 receives a pushing force in the distal direction, causing the opening member 18 to begin moving from its initial position in the distal direction relative to the catheter hub 14.

[0052] FIG. 4 shows the opening member 18 in a position slightly advanced from the initial position. Hereinafter, this position will be referred to as the "intermediate position" of the opening member 18. The intermediate position is a position between the initial position and the movement completion position of the opening member 18. The valve pressing portion 40 of the extension portion 38 contacts the inner surface of the valve body 26 (the pair of bill portions 260) as it reaches the intermediate position. The engagement force of the locking portion 42 of the extension portion 38 with the insertion portion 34 of the opening member 18 is greater than the force the extension portion 38 receives from the valve 16. Therefore, when the opening member 18 advances, the engagement between the locking portion 42 and the insertion portion 34 is not released. As a result, the extension portion 38 advances together with the opening member 18 without moving axially relative to the opening member 18, pushing the valve body 26 apart from the inside and opening the valve 16.

[0053] In this way, as the opening member 18 receives a pushing force in the distal direction, the opening member 18 moves from the initial position to the movement completion position relative to the catheter hub 14, and when the opening member 18 reaches an intermediate position, the extension portion 38 (specifically, the valve pressing portion 40) opens the valve 16. At this time, the insertion portion 34 of the opening member 18 is not in contact with the valve body 26. In other words, as the opening member 18 and the extension portion 38 advance together, the extension portion 38 contacts the valve body 26 prior to the opening member 18, thereby hastening the opening timing of the valve 16 compared to when the extension portion 38 is not present. For this reason, the "intermediate position" of the opening member 18 can be referred to as a "prior opening position" where the extension portion 38 opens the valve 16 prior to the opening member 18.

[0054] When the opening member 18 is in the intermediate position, the male connector 48 is not completely fitted into the proximal end (fixing member 22) of the catheter hub 14, and a minute gap that allows gas to pass through is present between the inner circumferential surface of the fixing member 22 and the outer circumferential surface of the male connector 48. Therefore, air in the hub lumen 15 can flow out of the proximal opening of the catheter hub 14 through this gap.

[0055] Therefore, as the valve 16 opens, blood flows into the catheter hub 14 (hub lumen 15) through the catheter body 12. As the blood flows in, the air in the hub lumen 15 is pushed proximally by the blood and is discharged to the outside of the catheter hub 14 through the gap between the fixing member 22 and the connector. As a result, almost the entire hub lumen 15 becomes filled with blood. If the catheter hub 14 is transparent, the user can visually observe from outside the catheter hub 14 how the hub lumen 15 is filling with blood.

[0056] As shown in Figure 5, by further inserting the male connector 48, the male connector 48 is completely mated with the base end (fixing member 22) of the catheter hub 14. The state in which the male connector 48 is completely mated means that the male connector 48 and the fixing member 22 are in close contact around the entire circumference, and are mated with each other in an airtight and liquidtight state. When the male connector 48 is completely mated with the base end of the catheter hub 14, the opening member 18 reaches the movement completion position. As the opening member 18 moves from the intermediate position to the movement completion position, the insertion portion 34 of the opening member 18 opens the valve 16 even more widely.

[0057] Furthermore, during the process in which the opening member 18 moves from the intermediate position to the movement completion position, the extension 38 comes into contact with an abutment portion 50, which is a specific portion located in the hub lumen 15, and receives a resistance force in the proximal direction from the abutment portion 50. In this embodiment, the abutment portion 50 is a part of the crimping pin 20. Note that the abutment portion 50 may be a portion other than the crimping pin 20. For example, if the crimping pin 20 is not provided, a part of the inner surface of the catheter hub 14 may constitute the abutment portion 50.

[0058] The engagement force of the locking portion 42 of the extension portion 38 with the insertion portion 34 of the opening member 18 is smaller than the resistance force that the extension portion 38 receives from the abutting portion 50. Therefore, after the extension portion 38 abuts against the abutting portion 50, as the opening member 18 further advances, the locking portion 42 elastically deforms outward, and the engagement between the locking portion 42 and the insertion portion 34 is released. As a result, as shown in FIG. 2B , the extension portion 38 moves relative to the insertion portion 34 in the proximal direction. Because the movement of the opening member 18 is not hindered by the extension portion 38, the opening member 18 can reach the movement completion position by being pushed distally by the male connector 48, as shown in FIG. 5 .

[0059] In this way, when the opening member 18 moves further from the intermediate position toward the distal end, the extension portion 38 abuts against the abutment portion 50 located in the lumen of the catheter hub 14 (hub lumen 15) and receives resistance from the abutment portion 50, and the resistance force received by the extension portion 38 from the abutment portion 50 causes the locking portion 42 to disengage from the opening member 18. Therefore, the extension portion 38 is displaced relative to the opening member 18, allowing the opening member 18 to reach the movement completion position.

[0060] This embodiment has the following advantages.

[0061] The catheter 10 includes an extension 38 supported by the insertion section 34 of the opening member 18. With this configuration, the timing of opening of the valve 16 can be accelerated during the process of connecting the male connector 48 to the catheter hub 14, compared to conventional valved catheters. This allows blood to flow into the catheter hub 14 and air to be expelled from the catheter hub 14 quickly after the opening member 18 begins to move. Furthermore, after the valve 16 opens, the extension 38 can be displaced relative to the opening member 18, allowing the opening member 18 to move to the movement completion position. This allows the male connector 48 to be connected to the catheter hub 14 without any problems.

[0062] When the opening member 18 moves further from the intermediate position toward the distal end, the extension portion 38 abuts against the abutment portion 50 provided in the hub lumen 15 and receives resistance force from the abutment portion 50. With this configuration, the extension portion 38 can be displaced relative to the opening member 18 with a simple configuration.

[0063] The extension portion 38 is movable relative to the opening member 18 in the axial direction of the catheter hub 14. When the extension portion 38 receives resistance force from the abutment portion 50, it moves relative to the opening member 18 in the proximal direction. With this configuration, the extension portion 38 can be displaced relative to the opening member 18 with a simple configuration.

[0064] The extension portion 38 has a valve pressing portion 40 that presses the valve 16 to open it when the opening member 18 reaches the intermediate position. The valve pressing portion 40 is inserted into the insertion portion 34 and protrudes distally from the insertion portion 34 when the opening member 18 is in the initial position. With this configuration, the extension portion 38 can be well supported by the insertion portion 34 of the opening member 18.

[0065] The insertion portion 34 of the opening member 18 has a side hole 36. The locking portion 42 protrudes outward from the insertion portion 34 through the side hole 36 and engages with the outer surface of the insertion portion 34. With this configuration, the locking portion 42 can be securely locked to the insertion portion 34.

[0066] The valve pressing portion 40 is a hollow cylindrical body. With this configuration, it is easy to ensure the rigidity required to open the valve 16, and good liquid permeability can be ensured.

[0067] The extension portion 38 has a valve pressing portion 40 that presses the valve 16 to open it when the opening member 18 reaches the intermediate position, and a locking portion 42 that is locked to the opening member 18. When the opening member 18 moves further distally from the intermediate position, the resistance force that the extension portion 38 receives from the abutting portion 50 causes the locking portion 42 to disengage from the opening member 18. With this configuration, relative movement of the extension portion 38 with respect to the opening member 18 is prevented while the locking portion 42 is locked to the opening member 18, so the valve 16 can be opened by the valve pressing portion 40 moving distally. Furthermore, after the valve 16 has opened, the locking portion 42 is released from engagement with the opening member 18, allowing the extension portion 38 to be displaced proximally relative to the opening member 18.

[0068] In the above-described embodiment, one mode of relative displacement of the extension portion 38 with respect to the opening member 18 is one in which the extension portion 38 is displaced axially relative to the opening member 18, but the present disclosure is not limited to this. For example, another mode of extension portion (not shown) may be configured to be elastically deformable so as to be displaced radially relative to the opening member 18. In this case, the other mode of extension portion opens the valve 16 by advancing together with the opening member 18, and displaces radially (e.g., radially inward) when it abuts against the abutment portion 50 and receives resistance from the abutment portion 50. This allows the opening member 18 to move to the movement completion position.

[0069] Instead of the extension 38 shown in FIG. 3, an extension according to a modified example described below may be employed.

[0070] The extension portion 60 according to the first modified example shown in FIG. 6 includes a valve pressing portion 40A, at least one locking portion 42, and at least one locking protrusion 62. The locking portion 42 of the extension portion 60 is the same as the locking portion 42 of the extension portion 38 shown in FIG. 3. In FIG. 6, the valve pressing portion 40A is a hollow cylindrical body. A pair of axially extending slits 64 are formed in the valve pressing portion 40A. The distal end of the valve pressing portion 40A is divided radially by the pair of slits 64. Therefore, the distal end of the valve pressing portion 40A has two divided pieces 66. Because of the pair of slits 64, the pair of divided pieces 66 elastically deform toward each other when the extension portion 60 is assembled to the insertion portion 34 (see FIG. 7A) during the assembly process. This allows the extension portion 60 to be easily assembled to the insertion portion 34.

[0071] The locking projections 62 are provided at the tip end of each segment 66. Thus, the extension portion 60 has a pair of locking projections 62. The pair of locking projections 62 protrude radially outward from the outer peripheral surface of the valve pressing portion 40A. As shown in FIG. 7A , when the opening member 18 is in the initial position, the locking projections 62 are spaced axially from the tip end of the insertion portion 34.

[0072] 7B , the locking protrusion 62 can come into contact with the distal end of the insertion section 34 when the extension section 60 moves in the proximal direction relative to the insertion section 34. The locking protrusion 62 defines the maximum relative displacement of the extension section 60 in the proximal direction relative to the opening member 18. Because the locking protrusion 62 is provided in this manner, it is possible to prevent the extension section 60 from coming off the insertion section 34 when the extension section 60 moves in the proximal direction relative to the insertion section 34.

[0073] An extension 70 according to a second modified example shown in FIG. 8 includes a valve pressing portion 40 and at least one locking portion 72. The valve pressing portion 40 of the extension 70 is the same as the valve pressing portion 40 of the extension 38 shown in FIG. 3. In FIG. 8, the extension 70 includes a pair of locking portions 72. Each locking portion 72 includes an arm 74, a first locking claw 76, and a second locking claw 78. The arm 74 extends from the base end of the valve pressing portion 40. The distal end of the arm 74 is a free end. The first locking claw 76 protrudes from the arm 74 toward the valve pressing portion 40. The first locking claw 76 is provided at the longitudinal middle of the arm 74. The first locking claw 76 has the same function as the locking claw 46 of the extension 38 shown in FIG. 3.

[0074] 9A , when the opening member 18 is in the initial position, the first locking claw 76 is locked to the opening member 18 (insertion portion 34). The second locking claw 78 is disposed closer to the tip than the first locking claw 76. The second locking claw 78 protrudes from the arm 74 toward the valve pressing portion 40. The second locking claw 78 is provided at the tip of the arm 74. When the opening member 18 is in the initial position, the second locking claw 78 is spaced axially from the tip of the insertion portion 34.

[0075] 9B , the second locking claw 78 can come into contact with the distal end of the insertion section 34 when the extension section 70 moves in the proximal direction relative to the insertion section 34. The second locking claw 78 defines the maximum relative displacement of the extension section 70 in the proximal direction relative to the opening member 18. Because the second locking claw 78 is provided in this manner, it is possible to prevent the extension section 70 from coming off the insertion section 34 when the extension section 70 moves in the proximal direction relative to the insertion section 34.

[0076] As shown in Fig. 10A, the extension portion 80 according to the third modification is substantially cylindrical and covers the distal end of the insertion portion 34. In Fig. 10A, the opening member 18 is located in the initial position. The extension portion 80 is supported by the outer peripheral surface of the distal end of the insertion portion 34. The extension portion 80 is elastically deformable and is made of, for example, an elastomer material.

[0077] 11 , the extension 80 has a dividing surface formed by a slit 81 extending from the distal end surface to the side surface. Therefore, the extension 80 has a pair of halves 82 divided by the slit 81. The slit 81 extends to the vicinity of the proximal end of the extension 80. There is no slit 81 at the proximal end of the extension 80, and the pair of halves 82 are connected. A tapered portion 83 that narrows in diameter toward the distal end is formed at the distal end of the extension 80.

[0078] As shown in FIG. 10B , when the opening member 18 advances to the intermediate position, the tip (tapered portion 83) of the extension portion 80 comes into contact with the inner surface of the valve 16, and the extension portion 80 pushes the valve body 26 apart from the inside, thereby opening the valve 16. As the extension portion 80 pushes the valve body 26 apart from the inside, the extension portion 80 receives a force from the valve body 26 due to friction generated by the contact between the extension portion 80 and the valve body 26. This force acts to open the pair of half portions 82. As a result, blood can flow into the opening member 18 through the opened extension portion 80. As the opening member 18 moves to the intermediate position, the axial length of the extension portion 80 does not substantially change. In other words, the resistance force that the extension portion 80 receives from the valve body 26 when the opening member 18 moves to the intermediate position is smaller than the force required to shorten the axial length of the extension portion 80.

[0079] As shown in Figure 10C, when the opening member 18 advances further from the intermediate position and reaches the movement completion position, the opening member 18 opens the valve 16 to its maximum extent. Meanwhile, as the opening member 18 reaches the movement completion position, the frictional force between the extension 80 and the valve body 26 increases, and the resistance force that the extension 80 receives from the valve body 26 becomes greater than the force required to shorten the axial length of the extension 80. As a result, the extension 80 opens even more than in the state shown in Figure 10B and contracts in the axial direction.

[0080] When the extension portion 80 is contracted in the axial direction, the tip of the extension portion 80 is displaced outward from the position that covers the tip opening of the insertion portion 34, and therefore does not impede the flow of fluid. In this case, the extension portion 80 is deformed, for example, into a bellows shape. In this way, when the opening member 18 moves further from the intermediate position toward the tip, the extension portion 80 receives resistance from the inner surface of the valve 16 and changes shape to expose the tip of the insertion portion 34.

[0081] The extension portion 80 according to the third modification can hasten the opening timing of the valve 16 with a simple configuration.

[0082] As shown in Fig. 12A, the extension portion 90 according to the fourth modification is substantially cylindrical and covers the distal end of the insertion portion 34. In Fig. 12A, the opening member 18 is located in the initial position. The extension portion 90 is supported by the outer peripheral surface of the distal end of the insertion portion 34. The extension portion 90 is made of an elastomer material. Therefore, the extension portion 90 is elastically deformable. The extension portion 90 is movable axially relative to the opening member 18.

[0083] 13 , the extension portion 90 is formed with a pair of slits 91 extending from the base end surface toward the tip end. The pair of slits 91 are provided on opposite sides of the extension portion 90 in the circumferential direction. None of the slits 91 reaches the tip of the extension portion 90. The extension portion 90 is formed with a pair of holes 92 penetrating the inner and outer circumferential surfaces of the extension portion 90. The pair of holes 92 are provided on opposite sides of the extension portion 90 in the circumferential direction, at positions shifted 90° from the pair of slits 91.

[0084] 12B , when the opening member 18 advances to the intermediate position, the tips of the extensions 90 come into contact with the inner surface of the valve 16, and the extensions 90 push the valve body 26 apart from the inside, thereby opening the valve 16. In the process of the extensions 90 pushing the valve body 26 apart from the inside, the extensions 90 receive a force from the valve body 26 due to the frictional force generated by the contact between the extensions 90 and the valve body 26. This force is smaller than the static frictional force between the insertion portion 34 and the extensions 90. Therefore, when the opening member 18 advances to the intermediate position, no relative movement of the extensions 90 occurs with respect to the opening member 18.

[0085] 12C , when the opening member 18 further advances from the intermediate position and reaches the movement completion position, the opening member 18 opens the valve 16 to its maximum extent. As the opening member 18 moves from the intermediate position to the movement completion position, the extension 90 comes into contact with the abutment portion 50 (e.g., the crimping pin 20) and receives a resistance force from the abutment portion 50 in the proximal direction. In this case, the static friction force between the insertion portion 34 and the extension 90 is smaller than the resistance force received by the extension 90 from the abutment portion 50. Therefore, after the extension 90 abuts against the abutment portion 50, as the opening member 18 further advances, the extension 90 moves relative to the insertion portion 34 in the proximal direction. As such, when the opening member 18 further moves from the intermediate position toward the distal end, the extension 90 abuts against the abutment portion 50 provided on the hub lumen 15 and receives a resistance force from the abutment portion 50, thereby moving relative to the opening member 18 in the proximal direction.

[0086] Meanwhile, as the extension portion 90 moves relative to the insertion portion 34, the cylindrical main body portion 341 of the insertion portion 34 pushes the extension portion 90 apart from the inside. Also, as the extension portion 90 moves relative to the insertion portion 34, the ribs 342 of the insertion portion 34 are inserted into the slits 91 of the extension portion 90. In this way, the slits 91 allow the ribs 342 to enter as the opening member 18 moves further from the intermediate position toward the distal end.

[0087] The extension portion 90 according to the fourth modification has a simple configuration, which can advance the opening timing of the valve 16. Furthermore, since the rib 342 does not hinder the relative movement of the extension portion 90, the extension portion 90 can perform its function well.

[0088] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments.

Claims

1. A catheter comprising: a catheter body; a catheter hub connected to the proximal end of the catheter body; a valve arranged to separate a hub lumen, which is a hollow portion of the catheter hub, into a distal region and a proximal region; and an opening member arranged in the hub lumen, having an insertion portion facing the valve, which opens the valve by means of the insertion portion as the opening member moves distally relative to the catheter hub, to enable fluid communication between the distal region and the proximal region in the hub lumen, wherein the opening member has an extension portion supported by the insertion portion of the opening member, the tip of which is located distally of the insertion portion; a catheter in which, during the process of the opening member receiving a pushing force toward the distal end and moving from an initial position to a movement completion position relative to the catheter hub, the extension portion opens the valve when the opening member reaches an intermediate position between the initial position and the movement completion position, and as the opening member moves further from the intermediate position toward the distal end, the extension portion receives a resistance force equal to or greater than a predetermined value, causing at least a portion of the extension portion to displace relative to the opening member, thereby allowing the opening member to reach the movement completion position.

2. A catheter according to claim 1, wherein, when the opening member moves further from the intermediate position toward the distal end, the extension abuts against an abutment portion provided in the hub lumen and receives the resistance force from the abutment portion.

3. A catheter according to claim 2, wherein the extension portion is movable relative to the opening member in the axial direction of the catheter hub, and when the extension portion receives the resistance force from the abutment portion, it moves relative to the opening member in the proximal direction.

4. A catheter according to claim 3, wherein the extension section has a valve pressing section that presses the valve to open when the opening member reaches the intermediate position, and the valve pressing section is inserted into the insertion section and protrudes from the insertion section toward the distal end when the opening member is located at the initial position.

5. A catheter according to claim 4, wherein the insertion section of the opening member has a side hole and a locking section that is locked to the opening member, and the locking section protrudes outward from the insertion section through the side hole and engages with the outer surface of the insertion section.

6. A catheter according to claim 4 or 5, wherein the valve pressing portion is a hollow cylindrical body.

7. A catheter according to claim 3, wherein the extension portion has a valve pressing portion that presses the valve to open it when the opening member reaches the intermediate position, and a locking portion that is locked to the opening member, and when the opening member moves further from the intermediate position toward the tip, the resistance force that the extension portion receives from the abutting portion causes the locking portion to be released from the opening member.

8. A catheter according to claim 7, wherein the distal end of the extension section is provided with a locking projection that can abut against the distal end of the insertion section, and the locking projection defines the maximum relative displacement of the extension section in the direction of the proximal end with respect to the opening member.

9. A catheter according to claim 7, wherein the locking portion has an arm extending from the valve pressing portion, a first locking claw protruding from the arm, and a second locking claw protruding from the arm, the first locking claw locks with the opening member when the opening member is located in the initial position, and the second locking claw is positioned further towards the tip than the first locking claw and defines the maximum relative displacement of the extension portion towards the base end with respect to the opening member.

10. A catheter according to claim 1, wherein when the opening member is located in the initial position, the extension portion covers the tip of the insertion portion, and when the opening member moves further from the intermediate position toward the tip, the extension portion receives the resistance force from the inner surface of the valve and changes to a form that exposes the tip of the insertion portion.

11. A catheter according to claim 1, wherein the extension is movable relative to the opening member in the axial direction of the catheter hub, and when the opening member is located in the initial position, the extension covers the distal end of the insertion section, and when the opening member moves further from the intermediate position toward the distal end, the extension abuts against an abutment provided in the hub lumen and receives the resistance force from the abutment, thereby moving relative to the opening member in the proximal direction.

12. A catheter according to claim 11, wherein the insertion section comprises a cylindrical main body having an inner cavity which is a fluid passageway, and a rib protruding from the outer circumferential surface of the cylindrical main body and extending in the axial direction, and the extension section is formed with a slit which allows the rib to enter when the opening member moves further from the intermediate position towards the tip.

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