Pressure-feedback-type hydraulic impactor

The invention discloses a pressure-feedback-type hydraulic impactor, which consists of an impactor body and a control valve block. The impactor body comprises a drill rod, a piston, a cylinder body, a piston rear sleeve and a nitrogen chamber, wherein the piston is installed in the cylinder body and divides the cylinder body into a piston front chamber and a piston rear chamber; and the piston front chamber, the piston rear chamber and the nitrogen chamber are isolated from one another. The control valve block consists of a sliding valve, a sequence valve and an adjustable hydraulic-control two-position three-way reversing valve, wherein the sliding valve is of a two-position three-way structure, and a hollow chamber inside the sliding valve is divided into a normally-high-pressure chamber a1, an alternating chamber a2 and a control chamber a3 by a spool of the sliding valve. The impactor body and the control valve block are separately arranged. By adopting a pressure-feedback principle and using the sequence valve and the adjustable hydraulic-control two-position three-way valve to be organically connected with the hydraulic impactor body, the intelligent switching of the slidingvalve is realized. Therefore, the impactor disclosed by the invention can realize the function of stepless impact energy adjustment according to different properties of working objects.