US Patent 7165480 Hand tool having positioning and locking joint

A hand tool having: a head provided at an end thereof with an arcuate face and a handle, connected to the head to allow rotational movement in relation to the head. The handle is formed with a first receiving hole, a second receiving hole and a third receiving hole communicating with the second receiving hole. A positioning and locking joint, including: a first stop mechanism is received in the first receiving hole, and has an end constantly urged against one of a plurality of teeth formed on the arcuate face of the head. A second stop mechanism is received in the second receiving hole and has an end selectively engaging one of the teeth on the arcuate face of the head An operative pin is received in the third receiving hole for controlling the second stop mechanism to engage with or disengage from one of the teeth.