Torque spanner or wrench - has forked handle containing rotatable head and cam which passes detent when fixed torque is reached

摘要

The torque spanner has a handle with a forked or slotted end containing a freely rotatable head capable of engaging a screw threaded device. Rigidly keyed to the head is a finger or cam which moves through the fork or slot. The fork or slot contains a spring-loaded detent which is engaged by the cam and which allows the cam to pass when a predetermined torque is applied to the head. The detent may allow the cam to pass when the handle is moved in a direction to tighten the screw threaded device but may form a positive stop against movement of the handle in the opposite direction.