PERFORMING WORK WITH A TOOL

摘要

Apparatus for performing work by advancing a tool against resistance thereto, and in particular an excavator attachment or a rock, concrete or engine crusher in which a pivoted jaw member (16) is advanced by a hydraulic ram (30) against a fixed plate (22), includes percussion means in the form of a hydraulic hammer acting against a fixed anvil (46, 50) to assist the ram. Hydraulic fluid can be diverted from the ram to the hammer as required.