Abstract: Hydraulic fluid pressure moves a piston (22) against a body of incompressible fluid (14), compressing a spring (42). The pressure is released, and the force of the stored energy in the spring (42) is transmitted to the piston (22) by the body of fluid (14) and drives the piston (22) through its power stroke. The fluid (14) is vented to an outlet (8) before the piston (22) reaches the end of its power stroke, removing the force from the piston (22) and allowing it to free travel through the remainder of the stroke. When the motor (2) is operating and the load is removed from the piston (22), the hydraulic fluid inlet (10) is short-circuited to the outlet (8) and the motor (2) automatically shuts off.

Abstract: Hydraulic fluid pressure moves a piston (22) against a body of incompressible fluid (14), compressing a spring (42). The pressure is released, and the force of the stored energy in the spring (42) is transmitted to the piston (22) by the body of fluid (14) and drives the piston (22) through its power stroke. The fluid (14) is vented to an outlet (8) before the piston (22) reaches the end of its power stroke, removing the force from the piston (22) and allowing it to free travel through the remainder of the stroke. When the motor (2) is operating and the load is removed from the piston (22), the hydraulic fluid inlet (10) is short-circuited to the outlet (8) and the motor (2) automatically shuts off.

Abstract: A power driven reciprocating hammer strikes a tool shaft or moil. A split ring of larger diameter than the moil extends about a reduced diameter shank portion of the moil and makes contact with a one-piece bushing, through which the moil extends, when the moil approaches its outward end of travel. The bushing is moved against a body of elastomeric material which is housed within a nose cap. Such material absorbs the remaining energy in the moil and in so doing changes its shape, including by flowing radially outwardly through an axial space provided between the nose cap and the nose end of the housing. Cross pins removably connect axially projecting mounting lug portions of the nose cap to the nose end of the housing.

Abstract: A pair of side-by-side hydraulic fluid supply and return hoses are connected to side-by-side end ports at the free end of a journal block which is located between two spaced apart bearing blocks. A pair of coaxial, oppositely projecting, tubular journals carried by the journal block, and rotationally received in coaxial blind socket portions of passageways formed in the bearing blocks, serve to mount the journal block and hoses connected thereto for pivotal movement relative to the bearing blocks. Passageways in the journal block communicate the side-by-side hose ports with the interiors of the tubular journals which in turn communicate with the passageways in the bearing blocks via the blind sockets. The bearing blocks are detachably mounted onto an upper rear frame portion of a hydraulic tool, such as a hydraulic breaker. The bearing block passageways have ports on corresponding mounting sides of the bearing blocks which communicate with inlet and outlet ports in the tool housing.