Valved needle assembly
A valved needle assembly including a needle hub provided to a proximal end side of a hollow needle, and a valve member incorporated therein for blocking communication with the hollow needle. A protrusion protrudes from a distal end side toward a proximal end side inside the needle hub and the valve member blocks the proximal end side of the protrusion inside the needle hub. A central valve part of the valve member having a slit moves toward the protrusion such that the slit is opened and placed in communication by the protrusion. The central valve part includes a distal end tubular part and a proximal end tubular part extending from its outer circumferential portion toward the distal end side and the proximal end side respectively.
1. A valved needle assembly comprising:
a hollow needle;
a needle hub provided to a proximal end side of the hollow needle; and
a valve member incorporated inside the needle hub and blocking communication with the hollow needle, wherein
a protrusion is provided inside the needle hub and protrudes from a distal end side toward a proximal end side, and the valve member blocks the proximal end side of the protrusion inside the needle hub,
a central valve part of the valve member positioned in opposition to the protrusion and having a slit is configured to be moved toward the protrusion such that the slit is opened and placed in a communicating state by the protrusion,
the central valve part is provided with a distal end tubular part extending from an outer circumferential portion thereof toward the distal end side, and a proximal end tubular part extending from the outer circumferential portion thereof toward the proximal end side, and
the valve member includes an outer circumferential guiding projection projecting radially outward from an outer circumferential surface of the central valve part and configured to move in contact with an inner circumferential surface of the needle hub.
2. The valved needle assembly according to claim 1 , wherein an inner circumferential surface of the distal end tubular part of the valve member includes a guide surface that is in contact with an outer circumferential surface of the protrusion of the needle hub.
3. The valved needle assembly according to claim 1 , wherein
the protrusion of the needle hub comprises a tubular protrusion formed in a tubular shape, and
an inner circumferential surface of the distal end tubular part of the valve member includes a sealing face that is in contact with an outer circumferential surface of the tubular protrusion of the needle hub about an entire circumference.
4. The valved needle assembly according to claim 3 , wherein the distal end tubular part of the valve member includes an annular sealing projection projecting toward a radial inside, and an inner circumferential surface of the annular sealing projection comprises the sealing face.
5. The valved needle assembly according to claim 3 , wherein the distal end tubular part of the valve member includes a clamping fit part fitted externally onto the tubular protrusion in an expanded state in which the clamping fit part is pushed open, and an inner circumferential surface of the clamping fit part comprises the sealing face.
6. The valved needle assembly according to claim 3 , wherein the distal end tubular part of the valve member includes a pressing projection projecting on an outer circumferential surface of the distal end tubular part and pressed against the inner circumferential surface of the needle hub, and the inner circumferential surface of the distal end tubular part is brought into contact with the outer circumferential surface of the tubular protrusion by a pressing reaction force of the pressing projection against the needle hub such that the sealing face is constituted.
7. The valved needle assembly according to claim 3 , wherein
in the distal end tubular part of the valve member, a portion that does not constitute the sealing face is longer than a portion that constitutes the sealing face, and
due to the central valve part of the valve member being moved toward the protrusion of the needle hub, the portion that does not constitute the sealing face is configured to deform in a corrugated shape in a lengthwise direction such that a length of the distal end tubular part is shortened.
8. The valved needle assembly according to claim 1 , wherein an outer circumferential surface of the valve member includes a compressing projection exerting a compression force on the slit of the valve member in a direction of closing by utilizing a contact reaction force against the needle hub due to contact with the inner circumferential surface of the needle hub.
9. The valved needle assembly according to claim 1 , wherein an air vent passage is provided and configured to discharge air in a space located in front of the valve member within the needle hub to an outside when the valve member moves to the distal end side within the needle hub.
10. The valved needle assembly according to claim 1 , wherein in the valve member, the distal end tubular part is thinner than the proximal end tubular part.
11. The valved needle assembly according to claim 1 , wherein the distal end tubular part of the valve member has a length that covers the protrusion of the needle hub as far as a distal end thereof.
12. The valved needle assembly according to claim 1 , wherein the valve member includes a tapered part that gradually decreases in diameter from the central valve part toward the distal end tubular part, and on a radially inner side of the tapered part, a gap is provided between the tapered part and the protrusion of the needle hub.
13. The valved needle assembly according to claim 1 , wherein
an outer circumferential surface of a protruding end of the protrusion of the needle hub includes a tapered sloping face that gradually decreases in diameter toward the central valve part, and
the valve member includes an overlapping part having a sloping inner face that gradually decreases in diameter from the distal end tubular part toward the central valve part while being in contact and overlapped with the tapered sloping face of the protrusion.
14. The valved needle assembly according to claim 1 , wherein the valve member includes a connecting part that gradually increases in thickness dimension from the distal end tubular part toward the central valve part.
15. A valved needle assembly comprising:
a hollow needle;
a needle hub provided to a proximal end side of the hollow needle; and
a valve member incorporated inside the needle hub and blocking communication with the hollow needle, wherein
a protrusion is provided inside the needle hub and protrudes from a distal end side toward a proximal end side, and the valve member blocks an inside of the needle hub,
a central valve part of the valve member positioned in opposition to the protrusion and having a slit is configured to be moved toward the protrusion such that the slit is opened and placed in a communicating state by the protrusion,
the central valve part is provided with a proximal end tubular part extending from an outer circumferential portion thereof toward the proximal end side, and a compression force is exerted on an outer circumferential surface of the central valve part due to contact against the needle hub, and
the valve member includes an outer circumferential guiding projection projecting radially outward from the outer circumferential surface of the central valve part and configured to move in contact with an inner circumferential surface of the needle hub.
16. The valved needle assembly according to claim 15 , wherein an entirety of the valve member including the central valve part provided with the proximal end tubular part is positioned further on the proximal end side than a tip portion of the protrusion and housed inside the needle hub without fitting on an outer circumferential surface of the protrusion.
17. A valved needle assembly comprising:
a hollow needle;
a needle hub provided to a proximal end side of the hollow needle; and
a valve member incorporated inside the needle hub and blocking communication with the hollow needle, wherein
a protrusion is provided inside the needle hub and protrudes from a distal end side toward a proximal end side, and the valve member blocks an inside of the needle hub,
a central valve part of the valve member positioned in opposition to the protrusion and having a slit is configured to be moved toward the protrusion such that the slit is opened and placed in a communicating state by the protrusion,
the central valve part is provided with a distal end tubular part extending from an outer circumferential portion thereof toward the distal end side, and a proximal end tubular part extending from the outer circumferential portion thereof toward the proximal end side,
the distal end tubular part extends as far as a distal end of the inside of the needle hub, and the distal end tubular part includes a sealing face that is in contact with a distal end outer circumferential surface of the protrusion about an entire circumference, and
the valve member includes an outer circumferential guiding projection projecting radially outward from an outer circumferential surface of the central valve part and configured to move in contact with an inner circumferential surface of the needle hub.
18. The valved needle assembly according to claim 17 , wherein
the distal end tubular part is in contact with only the distal end outer circumferential surface of the protrusion about the entire circumference in a compressed state, and
due to the proximal end tubular part being pressed to the distal end side by an external instrument, a lengthwise middle portion of the distal end tubular part is configured to deform in a radial direction.
19. The valved needle assembly according to claim 1 , wherein the outer circumferential guiding projection has an outside diameter dimension larger than those of the distal end tubular part and the proximal end tubular part.
20. The valved needle assembly according to claim 15 , wherein the outer circumferential guiding projection has an outside diameter dimension larger than that of the proximal end tubular part.