Patent ID: 8733468

Claim:
A hydraulic hammer comprising: a powercell housing defining a hydraulic inlet and a hydraulic outlet; a machine mount defining a plurality of pin receiving bores attached to the powercell housing; a work tool partially received in, and movable with respect to, the powercell housing; a switching spool valve member positioned in the powercell housing and being movable between a first position and a second position, and including a control hydraulic surface; a sleeve/liner assembly positioned in the powercell housing and defining a centerline; a piston with a plurality of hydraulic surfaces positioned in the sleeve/liner assembly and movable along the centerline between a first position in contact with the work tool and a second position out of contact with the work tool; the control hydraulic surface being exposed to fluid pressure in a switching passage, which includes a segment defined by the sleeve/liner assembly; and the sleeve/liner assembly includes an elongated sleeve that has a length and includes an outer surface defining a channel extending along a segment of the length, an inner surface defining an annular groove that encircles the centerline, and further defining a side port extending from the annular groove to the channel.