摘要 |
A clutch and safety overload for portable, power driven, hand tools is described. The clutch comprises a fixed half and a movable half which are urged into contact with each other more firmly as the load requirements increase. The load torque is fed back to the movable clutch half by a gear driven by the output spindle and which meshes with helical gearing carried by a jackshaft on which the movable clutch half is mounted. In one embodiment the overload safety is part of the clutch itself and involves a rotation of the movable clutch half in response to an overload condition, and against a spring force, which causes it to be displaced axially with respect to the jackshaft and out of engagement with the fixed clutch half. In a second embodiment, the overload safety comprises a mechanical linkage which disengages the clutch halves when the output stroke of the driven tool exceeds a predetermined amount. |