Abstract: An endoscope treatment instrument having a sheath, a rotation axis extending in a width direction orthogonal to a longitudinal direction of the sheath, a plate formed with a first opening through which the rotation axis passes and a second opening having a width different from the width of the first opening, a forceps piece rotatably supported about the first opening and the rotation axis passing through the second opening, and a wire connected to a proximal end portion of the plate.

Abstract: A wet type friction clutch and an electromagnetic clutch is disclosed wherein a pilot clutch 61 is disposed in a magnetic flux path 95 of an electromagnet 57 and is kept between an armature 71 and the electromagnet 57. Upon excitation of the electromagnet 57, the armature 57 is retracted to allow the pilot clutch 61 to be coupled. The pilot clutch 61 includes a plurality of clutch plates 87, 89 which are interleaved with respect to one another for sliding movements. Adjacent clutch plates 87, 87A, 87B, 89, 89A, 89B, 89C, 89D, 89E, 89F are formed with oil guide passageways 86, 96, 98, 106, 108, 110, 114 to create a hydrodynamic pressure effect to allow the clutch plates to be separated with a limited drag torque.

Abstract: A wet type friction clutch and an electromagnetic clutch is disclosed wherein a pilot clutch 61 is disposed in a magnetic flux path 95 of an electromagnet 57 and is kept between an armature 71 and the electromagnet 57. Upon excitation of the electromagnet 57, the armature 57 is retracted to allow the pilot clutch 61 to be coupled. The pilot clutch 61 includes a plurality of clutch plates 87, 89 which are interleaved with respect to one another for sliding movements. Adjacent clutch plates 87, 87A, 87B, 89, 89A, 89B, 89C, 89D, 89E, 89F are formed with oil guide passageways 86, 96, 98, 106, 108, 110, 114 to create a hydrodynamic pressure effect to allow the clutch plates to be separated with a limited drag torque.