Patent ID: 8118819
Filing Date: 2012-02-21
Classification: A61B

Abstract:
1. A medical treatment tool, comprising: a flexible wire configured to perform a predetermined treatment on a biological tissue; a wire operation portion which is configured to operate said wire back-and-forth; a first wire holding member which is provided in a back-and-forth movable manner with respect to said wire, to hold the wire; a second wire holding member which is provided on a proximal side of said first wire holding member, in a back-and-forth movable manner in an axial direction, and is capable of holding said wire between itself and the first wire holding member; a flexible first sheath which is provided in contact with a proximal side of said second wire holding member; a flexible second sheath which is provided to cover said first sheath, in a back and-forth movable manner with respect to the first sheath; and a sheath operation portion which operates said second sheath back-and-forth; wherein said first wire holding member and said second sheath have a connection device which connects them to each other; and a connection releasing device which is configured to cause said second wire holding member to engage with said first wire holding member to limit the motion of said flexible wire to said first wire holding member, and which is configured to reset the connection between said first wire holding member and said second sheath thereby releasing said first wire holding member and said second wire holding member from said first sheath and said second sheath, respectively wherein the connection device comprises a pair of flexible projecting members which are deformable in a radial direction of the second sheath and projected from a proximal end to a distal end along an extension line of a periphery of the second sheath and each having a catch element jutted out inwardly on the distal end and a pair of latch holes each of which is perforated through the side wall of the first wire holding member and being deformable in the radial direction of the second sheath with which latch holes the catch elements are engaged respectively to the inside the first wire holding member to thereby connect the first wire holding member with the second sheath and wherein the first wire holding member and the second wire holding member have a latching device for latching with each other upon holding the wire therebetween, comprising the first coupling catch elements and the latch holes, and the connection releasing device comprising a coupling catch disposed to a position corresponding to the latch holes, on the second wire holding member, the connection releasing device having a wedge-like shape element expanding from the side wall surface at the distal end side of the second wire holding member to a top portion and having an external diameter slightly larger than an external diameter of the first wire holding member, disposed on the proximal end side thereof, wherein when the second wire holding member moves forwardly to the first wire holding member; said coupling catch is engaged into the latch hole on the second wire holding member, thereby releasing the connection between the first wire holding member and the second sheath to thereby connect the first wire holding member and the second wire holding member.