Source: {"pile_set_name": "USPTO Backgrounds"}

1. Field of the Invention
The present invention relates to a torque applicator comprising a housing in which is disposed a rotatable torque applicator stem actuated by a hydraulic or pneumatic double-acting piston to apply an intermittent torque on bolts, nuts etc. A torque applicator of this kind is known from Norwegian Patents 115.991 and 136.609. The present invention is a further development of these known torque applicators.
2. Prior Art and Summary of the Invention
The torque applicator of the present invention differs from the prior art in that the two members of a claw coupling are mounted on the rotatable torque applicator stem, one coupling member being fixed and non-movably mounted on the stem, and the other coupling member being mounted for axial movement on the stem. The movable coupling member is provided with a radial arm the free end of which co-operates with the double-acting piston to cause a reciprocating rotary movement of the axially movable coupling member on the applicator stem.
The movable coupling member is adapted to be moved axially on the torque applicator stem by hydraulic or pneumatic pressure on one and the other, respectively, axial end surfaces of the coupling member, in time with the actuation of the piston, the coupling member thereby being brought into and out of engagement with the fixed coupling member.