Patent ID: 7194939

Claim:
A pneumatic wrench, comprising: a striking mechanism including a cylindrical support seat having a closed first end face and an open second end face, a cam rotatably mounted on the first end face of the support seat, a cover mounted on the second end face of the support seat, and a hammer rotatably mounted in the support seat and engaged with the cam so that the hammer is driven by the cam to rotate in the support seat, wherein the hammer has a side face having a mediate portion formed with an axially extended protruding pivot shaft pivotally mounted in the support seat; the pivot shaft of the hammer has two opposite sides each formed with a protruding reinforcing rib to reinforce the structural strength of the hammer; the pivot shaft of the hammer has a first end formed with a first pivot shaft pivotally mounted in the first end face of the support seat and a second end formed with a second pivot shaft pivotally mounted in the cover; the support seat has an inner wall formed with an axially extended pivot slot for mounting the pivot shaft of the hammer; the pivot slot of the support seat has two opposite sides each formed with a receiving recess to receive the respective reinforcing rib of the pivot shaft.