摘要 |
An arrangement for operating hydraulic actuating means in a rock drilling machine, comprising pressure-con-trolled overcenter valves (7, 8) connected to conduits (5, 6) leading to chambers (3, 4) positioned on opposite sides of a piston (2) of a cylinder (1) or the like actuating means, and non-return valves (11, 12) connected in parallel therewith. In order to operate the cylinder (1), one or two cartridge-type regulating valves (14, 15; 25) are mounted therein so as to be controlled by means of electric signals for displacing the piston (2) of the cylinder (1) in the desired direction. In the arrangement, a single pressure fluid supply hose (13) and a single pressure fluid return hose (9) are required for the operation of the cylinders (1) and other actuating means. (Figure 1) |