Hydraulic adjuster for mine - has control spindle moving axially in piston to trigger control valve

摘要

The electro-hydraulic adjuster comprises cylinder, piston and rod and mechanical controller whose spindle moves freely axially within the piston to trigger the control valve. The spindle reaches firstly into the rod and otherwise connects to an electrical rotary transducer, using the valve to pressurise the cylinder spaces with control fluid. A switching piston is mounted on the spindle (80) to adjust axially without rotation and is here enclosed by a switching cylinder (12) placed axially on the spindle also. The cylinder spaces are loaded both sides of the switching piston with pressure control fluid by a primary control valve. The valves (13) are tripped by a transducer coupled electrically controlled circuit (5) and the spindle is allocated a brake element (14) on the transducer side. The element is operated by axially moving an adjuster piston (11) so as either to block or free the spindle (8). USE/ADVANTAGE - Underground mining. Adjuster compensates for brief or enduring overload and is amenable to logic system control.