Medical needle

1. A medical needle, comprising:

a needle portion;

a case which is capable of exposing a needle tip of the needle portion from a distal end, and is capable of accommodating the needle portion;

a movement mechanism which moves the needle portion inside the case until the needle tip protruding from the case is accommodated inside the case;

an operation portion for operating the movement mechanism, configured to allow a pressing operation in a pressing operation direction perpendicular to a movement direction of the needle portion when the needle portion is moved by the movement mechanism;

an operation member which is included in the movement mechanism and in which the operation portion is integrally formed;

an operation regulation portion that regulates the pressing operation of the operation portion; and

an engaging portion that is engaged with the operation regulation portion in the movement direction of the needle portion and overlaps the operation regulation portion in the pressing operation direction,

wherein:

the medical needle has an elongated shape in a longitudinal direction in which the needle portion extends, and, in the longitudinal direction, a side to which the needle tip protrudes is a distal end side and a side opposite the side to which the needle tip protrudes is a proximal end side,

the case comprises:

a first opening which opens in a direction toward the distal end side and from which the needle portion protrudes;

a second opening which is provided at an edge portion of the first opening and opens in a same direction as the first opening; and

a flat plate-shaped portion which extends from an end of the second opening in the longitudinal direction, the end of the second opening being positioned at an outside with respect to the edge portion in a radial direction of the first opening,

an end portion at the distal end of the flat plate-shaped portion is configured to function as the engaging portion and includes a flat surface portion extending in parallel with the longitudinal direction at an outside in the radial direction of the end portion at the distal end of the flat plate-shaped portion,

an end portion at the distal end of the operation member is provided with the operation portion, and the operation portion is provided with the operation regulation portion at the proximal end side of the operation portion,

the operation regulation portion is a notch which is formed to be opened to the proximal end side and to be concave in a U-shape along the movement direction of the needle portion, the notch comprising:

a first flat surface which is disposed at an outside with respect to the flat plate-shaped portion in the radial direction and extends in parallel with the longitudinal direction;

a bottom surface for the U-shape which extends from an end portion at the distal end side of the first flat surface radially inwardly in the pressing operation direction; and

a second flat surface which is disposed at an inside with respect to the flat plate-shaped portion in the radial direction and extends in parallel with the first flat surface in the longitudinal direction from an end portion at the distal end side of the bottom surface toward the proximal end side, and

the first flat surface is configured to face the flat surface portion from an outside in the radial direction when the end portion at the distal end side of the flat plate-shaped portion is inserted into the notch from the proximal end side such that the operation regulation portion and the engaging portion are engaged in the movement direction of the needle portion and overlap each other in the pressing operation direction, and

the first flat surface and the flat surface portion facing each other are configured to directly contact with each other to regulate the pressing operation.

2. The medical needle according to claim 1 , wherein

the operation regulation portion and the engaging portion are configured so as to be capable of switching between regulation of the pressing operation of the operation portion, and releasing of the regulation of the pressing operation of the operation portion.

3. The medical needle according to claim 1 , wherein

the operation portion causes the movement mechanism to operate due to the pressing operation of the operation portion to displace from a predetermined position, and

the operation regulation portion and the engaging portion are located in a displacement direction of the operation portion, and regulate the displacement of the operation portion.

4. The medical needle according to claim 1 , wherein

the operation regulation portion and the engaging portion regulate the pressing operation of the operation portion in a state where the needle tip is protruding from the case.

5. The medical needle according to claim 1 , wherein:

the movement mechanism includes a biasing member that biases the operation member toward the proximal end side to maintain the engagement of the operation regulation portion and the engaging portion by a force of the biasing member.

6. The medical needle according to claim 5 , wherein:

the biasing member is disposed between an inner surface of the case on the distal end side and a surface of the operation member on the distal end side,

the operation member is movable toward the distal end side relative to the case against the force of the biasing member and configured to cause release of the engagement of the operation regulation portion and the engaging portion to cause release of the regulation of the pressing operation of the operation portion by the operation regulation portion when the operation member moves toward the distal end side.

7. The medical needle according to claim 1 , further comprising, a securing portion that is separate from the operation member and to which the needle portion is secured, wherein

the operation member is disposed on an outer circumference of the securing member and moves integrally with the securing member.

8. The medical needle according to claim 1 , wherein

the operation member is configured to cause release of the regulation of the pressing operation of the operation portion by the operation regulation portion when the operation member moves toward the distal end side to cause withdrawal of the end portion at the distal end side of the flat plate-shaped portion from the notch and cause release of the engagement of the operation regulation portion and the engaging portion.

9. The medical needle according to claim 1 , wherein:

the operation member has a plate-shaped portion which extends continuously to the second flat surface and in a same direction as the second flat surface, and

the plate-shaped portion is configured such that, in an engagement state where the operation regulation portion and the engaging portion are engaged, an entirety of a surface at an outer side in the radial direction in the plate-shaped portion contacts a surface at an inner side in the radial direction in the flat plate-shaped portion.