Hydraulic rotary-percussive machines

摘要

A single hydraulic supply line feeds fluid under pressure to a hydraulic percussive machine with a percussion motor and a rotation motor. The feed passes through two valves of the constant volume priority flow dividing type. The first valve gives priority to the percussion motor to the extent of establishing idling speed. The second valve in the bypass of the first valve gives priority to the rotation motor while its bypass reaches the percussion motor. Working speed of the percussion motor can only be obtained after the rotation motor is up to speed and control of the feed above the priorities controls the percussion motor speed only.