Jam-proof hydraulic device for drill

The invention discloses a drilling rig anti-sticking hydraulic device which can automatically control advance speed of a hydraulic cylinder and has an anti-sticking function, which comprises an oil tank, a variable pump, a power source, an oil inlet filter, an oil-return filter, a control valve group, a telescopic cylinder, a beater mechanism and a rotary motor, wherein the control valve group comprises an overflow valve, a left change-over valve, a middle change-over valve and a right change-over valve, an anti-sticking valve group is arranged between the telescopic cylinder and the control valve group, and the anti-sticking valve group comprises a change-over valve, two one-way valves and an overflow valve. The drilling rig anti-sticking hydraulic device which is utilized can avoid happening sticking circumstance, which assures a drilling rig to normally work. The drilling rig anti-sticking hydraulic device is suitable for drilling rig such as a drilling rig for clamping stones and earth to rapidly form hol