Mine roof support for long wall of coal mining, has screw spindle that is formed without self locking structure such that rotation torque of hydraulic motor of screw spindle is controlled between minimum and maximum supporting forces

摘要

The mine roof support has two inversely arranged handle bars that are arranged between sole structure (1) and cap structure (2). The crank arms (3a,4a) in the handle bars are coupled in parallel with swing arms (3b,4b) through coupling links (3c,4c). The adjustable movement and supporting force are generated by engaging handle bars to screw spindle (5). The screw spindle is formed without self locking structure such that the rotation torque of hydraulic motor (6) of screw spindle is controlled between minimum supporting force and maximum supporting force.