Inventors:
Masahiko Kusama - Wentzville MO, US
Assignee:
S.P. Air Kabusiki Kaisha - Nagano Pref.
International Classification:
B25B013/46
US Classification:
81 5739, 81 5713, 81 5729
Abstract:
A hand-held power tool for inhibiting uncalled-for rotation of the output shaft and for self-compensating for wear. The tool comprises a housing, a braking member fixedly mounted in the housing and an output shaft mounted in the housing for rotation. The output shaft has an outer end portion for reception of an attachment. A ratchet wheel on the output shaft is adapted to be driven in one direction or the other, has a side face facing a first surface of a wear member, and has a plurality of recesses extending inward from the side face. The wear member is keyed to the output shaft for conjoint rotation. A plurality of engagement members are received one in each recess and biased outward against the first surface to bias a second surface of the wear member against the braking member for holding the ratchet wheel against rotation opposite the driven direction.