Patent ID: 6843485

Claim:
A chuck device in which a plurality of claws provided at an end of a body are opened, closed and slid by the rotation of a rotary sleeve and a tool is clamped by means of the claws, wherein an annular ratchet wheel is provided on the body, an annular nut member to be engaged with the claws and to be rotated together with the rotary sleeve is fitted in the body inside of the rotary sleeve, wherein said annular nut member has projections, a retainer spring member detachably retained with a tooth of the ratchet wheel is arranged outside of the ratchet wheel, the retainer spring member is arranged to rotate around the ratchet wheel in accordance with the rotation of the nut member, the retainer spring member is mounted on the nut member by convex/concave engagement means, a retainer portion keeps a condition that the ratchet wheel and the retainer spring member are retained to each other and a condition that the engagement between the ratchet wheel and the retainer spring member is released, and the retainer portion is disposed between the body and the rotary sleeve and defined by the retainer spring member and an inner surface of the rotary member, and wherein said projections of said annular nut member are disposed between said retainer spring member and said annular rachet wheel.