Endoscopic clip device and clip

An endoscopic clip device, comprising:

• a clip comprising a plurality of arms configured to grip a living body tissue, and a locking portion positioned on a proximal side of the arms;
• and
• a treatment instrument body comprising an elongated sheath, an operation wire which is inserted into the sheath such that the operation wire is movable forward and backward, and a distal connection portion positioned in a distal end of the operation wire;
• and
• a sleeve configured to be accommodated in the elongated sheath and accommodating the distal connection portion in a distal portion of the operation wire such that at least a portion of an inner diameter of the sleeve is smaller than an outer diameter of the locking portion when the distal connection portion is drawable from the accommodation portion,
• wherein the locking portion and the distal connection portion are locked and connected to each other around an axis of the operation wire, the operation wire is rotated to generate torques such that the locking portion, the distal connection portion, and the sleeve are axially rotated around the axis inside the sheath, the sleeve has a diameter enlargement portion which is positioned on the distal side and which is elastically self-openable, a diameter reduction step portion which is positioned on a proximal side of the diameter enlargement portion, and a cylindrical sleeve body which is positioned on the proximal side of the diameter enlargement portion from the diameter reduction step portion and whose radial rigidity is higher than radial rigidity of the diameter enlargement portion, and the inner diameter of the cylindrical sleeve body is smaller than the outer diameter of the locking portion when the distal connection portion is drawable from the accommodation portion.

A clip for an endoscopic treatment instrument, comprising:

• a locking portion that engages with a distal side of an operation wire inserted into an elongated sheath of an endoscopic treatment instrument through a distal connection portion of the endoscopic treatment instrument such that the operation wire is movable forward and backward;
• a plurality of arms positioned on a distal side of the locking portion on an opposite side with respect to the distal connection portion of the endoscopic treatment instrument and configured to open outward by a self-openable force;
• and
• a clamping member into which the plurality of arms is inserted, and whose position relative to the plurality of arms is displaced from a proximal side of the arms to a distal side of the arms such that the clamping member closes a plurality of claws formed at the distal side of the plurality of arms inward,
• wherein each of the arms comprises a bending portion which is bent outward such that a curvature radius on the proximal side of the arms is larger than a curvature radius on the distal side of the arms, the locking portion includes a base which is connected to the proximal side of the arms, an accommodation portion comprising a plurality of projection pieces formed to project to a proximal side of the locking portion from the base and internally having a space, and a plurality of protruding portions respectively formed to protrude inward on a proximal side of the projection pieces, the base has an annular shape formed by bending a plate material and causing edges of the plate material to abut on each other, the plurality of projection pieces is positioned apart from each other around the base having an annular shape, and a joint of the edges abutting on each other is positioned at an intermediate position between the projection pieces adjacent to each other, the base has a plurality of recesses recessed toward a distal side of the base and formed in a peripheral edge on a proximal side of the base, and the projection pieces are respectively formed to project to the proximal side from a bottom of the recesses.