CONTROL MECHANISM FOR ROCK CRACKING DEVICE

PURPOSE:To perform automation by a method wherein a pressure gauge and a timer are arranged to a control device to feed an oil pressure to a plurality of rock crackers and when an oil pressure is reduced or an oil pressure feed continuing time exceeds a set value, the feed of oil is stopped. CONSTITUTION:A rod-form rock cracker 1 to crush a rock through expansion created by an oil pressure is inserted in a hole drilled in a rock-bed. A pump unit 2 is operated and by operation of a control unit arranged to a booster unit 3, the rock cracker 1 is selected to feed oil thereto. A pressure signal from a pressure gauge 18 is read at the control unit and when a pressure attains a predetermined rated value, a timer is actuated. When a detected oil pressure is reduced (when a rock-bed is cracked), or when an oil feed continuing time exceeds a set value, a solenoid valve 5 of the rock cracker 1 is closed to stop the feed of oil and a solenoid valve 5 of the different cracker 1 is opened to feed oil. This constitution performs an automatic and high-efficient work to pressurize, in order, the rock crackers 1.