Abstract: A tool assembly (10), for example a hydraulic or pneumatic hammer assembly, comprises a housing (11) defining a chamber (16), a reciprocating work tool (20) arranged in the chamber for cyclical movement in a work stroke and a return stroke, and a tool retention member (80) arranged to restrain the work tool at the end of the work stroke. The tool assembly (10) includes a shock absorber arranged to absorb impact from the work tool at the end of a stroke. The shock absorber comprises an annular resilient flange (102, 154), which may be cantilevered from the tool retention member (80) to absorb impact at the end of the work stroke or may be provided on a bushing (150) arranged to absorb impact at the end of the return stroke. The shock absorbing flange reduces the transmission of shocks into the tool assembly, thereby providing increased life for tool assembly components.

Abstract: An engine accessory drive that has a primary drive driveable by a crankshaft of the engine is disclosed. The accessory drive includes a rotational member mounted on a drive shaft and driveable by the primary drive, the drive shaft having an axis of rotation offset from the axis of rotation of the crankshaft. The accessory drive further includes a secondary drive having a flexible continuous secondary drive member external of the engine and driveable by the rotational member, and at least one engine accessory driveable by the secondary drive. The at least one engine accessory includes at least a balance shaft.