ROTARY-PERCUSSION MACHINE Russian patent published in 2006 - IPC E21B6/00 B25D16/00 

FIELD: mechanical engineering, particularly drilling equipment used in building, geological survey and for drilling and blasting operation performing.

SUBSTANCE: rotary-percussion machine of compression-vacuum type may work in at least two modes. The rotary-percussion machine comprises body, drive, percussion mechanism arranged in guiding cylinder, which is rotationally installed in the body. The machine also has conversion mechanism, which converts drive rotation into reciprocation of percussion mechanism piston. The machine comprises bush, enclosing guiding cylinder and connected with it in radial direction. The bush may be axially displaced to install the bush in left and right extreme positions to provide percussion and rotary-percussion modes of operation correspondingly. Cam connected with bush is secured in the body. The cam provides the axial bush displacement along guiding cylinder. Bar is installed in the body and extends transversely to guiding cylinder axis. The cam is connected to the bush by corbel, which encloses the bush and installed on the bar to perform limited rotation about it. Corbel is provided with side extensions directed inwards to guiding cylinder axis and inserted in annular groove of the bush. The corbel also has one outer projection. Torsion spring is installed on the bar and has ends enclosing cam pin and outer projection to compress thereof.

EFFECT: increased reliability.

5 dwg