Patent ID: 7717191

Claim:
A multi-mode hammer drill comprising: a support member having a lock surface; a shift member mounted on a support member for movement in a first direction along the support member between a first mode position corresponding to a first mode of operation and a second mode position corresponding to a second mode of operation, the shift member having a cooperating lock surface; a biasing member configured to exert a biasing force on the shift member in a second direction that is different from the first direction and toward a lock position where the lock surface can engage against the cooperating lock surface, when the shift member is in the first position; an actuation member coupled to the shift member in a configuration that generates a force sufficient to overcome the biasing force and move the shift member to an unlock position where the lock surface cannot engage against the cooperating lock surface, wherein the actuation member generates the force as part of a shifting operation from the first mode of operation to the second mode of operation.