Patent ID: 8020424

Claim:
A ring compression device that applies force on a periphery of a ring to thereby compress the ring and fix the ring on a mounting body placed inside the ring, comprising: a non-rotatable substrate having a central axis; a plurality of longitudinal pressing members arranged on a first plane different from that of the substrate and radially around the central axis, each of said pressing members having one end pointing toward the central axis, the pressing members capable of freely moving toward or away from the central axis in the first plane; a rotating body configured to rotate around the central axis in second plane that is parallel to the first plane; and a driving mechanism having cam followers respectively provided on the pressing members and cam holes formed in the rotating body and respectively engaged with the cam followers, the driving mechanism being configured to integrally move, along with the rotation of the rotating body in one direction, all of the pressing members toward the central axis and apply force on the periphery of the ring with the one end of each of the pressing members; and a hooking mechanism that hooks the ring, the hooking mechanism having a claw member abutting on an edge face on one side of the ring on the side of the substrate and also having a movable claw member abutting on an edge face on the other side of the ring on the tip side of the specific pressing member, wherein the a tip of at least one of a first pressing member, at an initial position, is located on a circle around the central axis corresponding to the periphery of the ring, and tip ends of a plurality of second pressing members, at an initial position, are located outside of the circle, and the cam holes are configured to move the tip ends of the second pressing members toward the circle, and to move, once the tip ends of each of the second pressing members are located on the circle, all of the tip ends of the pressing members toward the central axis.