HYDRAULIC PERCUSSION MACHINE Russian patent published in 2007 - IPC E21C37/00 E02D7/10 

FIELD: mining and construction, particularly hydraulic percussion devices for percussion driving rod members in ground, oversized pieces breakage and so on.

SUBSTANCE: machine comprises body, striker, forward and reverse stroke chambers arranged in-between, additional chamber, control channel made in the body and flow control device to connect forward stroke chamber with liquid source, with accumulator and reverse stroke chamber in the end of striker stroke. After striker detention before direct stroke as system pressure becomes equal to predetermined pressure P_d forward stroke chamber is communicated with tank return line. The second control chamber of flow control device is spring-loaded with force calculated with accordance to P_d value. In the end of reverse stroke additional chamber is communicated with tank return line. In the end of direct stroke additional chamber is connected with liquid source, accumulator and reverse stroke chamber. Forward stroke chamber is made as slide and hydraulic cylinder fixedly connected thereto through rod of double action hydraulic cylinder piston. Chambers of said hydraulic cylinder are used as control chambers of flow control device. The first chamber of the hydraulic cylinder having lesser working area is permanently connected with direct stroke chamber. Said chamber is also communicated with liquid source, accumulator and reverse stroke chamber through throttle and slide. The second chamber having greater area is connected to additional chamber through control channel of the body and is spring-loaded with said spring through slide. Channel communicating direct stroke chamber with tank return line is closed with striker as additional chamber is connected with tank return line in the end of reverse stroke.

EFFECT: increased output due to increased impact frequency and power and improved reliability due to minimized energy losses during flow control device shifting between forward and reverse machine strokes.

2 cl, 1 dwg