Patent ID: 6578643
Filing Date: 2003-06-17
Classification: B25B

Abstract:
A pneumatic ratchet drive wrench, the wrench comprising:a housing; an air inlet supported by the housing, said inlet being sized and shaped for connection to a source of pressurized air; an air motor disposed in the housing and in fluid communication with the air inlet for receiving pressurized air, said motor including a rotatable drive shaft that rotates when pressurized air passes through said motor; a rocker disposed pivotably within the housing and operatively connected to the drive shaft so that rotation of the drive shaft induces oscillation of the rocker; at least one pawl pivotably attached to the rocker; an output member having teeth, the output member being mounted in the housing for rotation about its longitudinal axis and projecting from the housing for transmitting torque to an object, said pawl being shaped and sized for engagement with the output member teeth to turn the output member; and at least one spring supported in the housing for biasing said at least one pawl against the teeth, said at least one spring being shaped and sized for restraining the output member from rotation opposite the rotation induced by the pawl, wherein the spring includes a pawl-engaging portion engaging said pawl and biasing said pawl against the teeth and a stop portion engageable with the teeth to restrain the output member from rotation in a direction opposite that induced by the pawl.