Abstract: A unitary valve assembly for a fluid-activated, percussive paving breaker includes a valve chest having an outer sidewall forming an internal valve chamber, a sidewall within the internal chamber forming a valve bore, a reciprocal valve within the valve bore and a bottom plate permanently fastened to the outer sidewall. The inner sidewall forms a first annular, upstanding sealing seat for the valve, and the bottom plate forms a second annular, upstanding sealing seat for the valve. Passageways through the valve assembly are positioned so as to connect with high and low pressure chambers of a paving breaker, when the valve assembly is inserted into the paving breaker. For weight reduction, the valve assembly is made of acetal resin.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.

Abstract: A throttle lever for a paving breaker having rear housing bore. A valve assembly housing plug is removably inserted into the bore. A backhead plate retains the valve assembly housing plug in the bore. An elongated throttle lever has a first end pivotally trapped between the backhead plate and the valve assembly housing plug. A second end of the throttle lever extends above the backhead plate, and forms an operator contact surface. An intermediate portion between the first end and second end of the throttle lever operably contacts a fluid inlet valve.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.