PIT-FACE ENGINE Russian patent published in 2004 - IPC

FIELD: drilling equipment engineering.

SUBSTANCE: device has driving section and spindle section consisting of body, hollow output shaft, axial support, radial support. In body of spindle section opposite to ports for liquid flow into hollow output shaft not moveably relatively to the body a through flow bushing is placed serving as additional radial support and made with inner channels. Ports for flow of washing liquid in hollow output shaft and inner channels of through flow bushing are placed in such a way that bushing periodically covers ports for liquid flow during rotation of hollow output shaft. Axial support of hollow output shaft is spring-loaded.

EFFECT: higher drilling productiveness due to more effective destruction of rock by chisel during forcing of, except rotational, also additional axial vibrations(strikes) onto the chisel and better washing of pit-face of slurry by working fluid due to its feeding into pit-face area in form of portions forming impulse hydraulic strikes in drilling area.

2 cl, 4 dwg