To provide a new opening/closing damper, having stability, which can obtain stable opening/closing and surely stop in an arbitrary position, in the case of opening/closing an opening/closing member.
A device comprises a cylindrical cylinder tube 1, columnar screw shaft 11 formed with a helical guide groove 11' and a spring clutch 21, in a rod side end of the cylinder tube 1, a rod side flange 3 inserting the screw shaft 11 guided is fitted to be secured and a head side flange 5 is fixedly fitted, in a head side of the screw shaft 11, a guide piston 18 and the spring clutch 21 are insertion supported. By float fitting a protrusion part 3' provided in the rod side flange 3 to the guide groove 11' of the screw shaft 11, it is guided, while rotated, to be arranged movably in an axial direction. The spring clutch 21 is constituted so as to apply small resistance in a rotational direction relating to the screw shaft 11 in a direction drawing it out so as to apply relatively large resistance relating to the screw shaft 11 in a direction retracting it.
UCHIUMI KIYOSHI
ISHIKAWA HAJIME
