Patent ID: 7089640

Claim:
A tool for installing a retaining ring such that the tool is to be used for the retaining ring which is provided with cuts in two places of a portion opposite to an opening in the retaining ring, wherein at an end surface of a holder provided at an end of the tool is formed a depression into which the portion opposite to the opening in the retaining ring is movably insertable, a full back surface of the depression at the end of the holder comprises plate members, and a back area in the inner periphery of the depression comprises a contact portion to contact the retaining ring at the portion opposite to the opening in the outer periphery of the retaining ring, the back area of said depression being provided with position control means positioned in the cuts of the retaining ring in an inserted state for controlling a position of the retaining ring in the inserted state, sheltering areas being arranged outside two sides of the retaining ring in the inserted state, and fall-off prevention means being provided at the holder for preventing fall-off of the retaining ring and from which the retaining ring can be easily detached, and wherein by providing a pair of protrusions in the back of the movably inserted depression, by setting a dimension between said protrusions narrower than a dimension of angular apertures to centers in the cuts in the two places of the portion opposite to the opening in the retaining ring, the protrusions shall be the fall-off prevention means and the position control means.