Abstract: Disclosed is a tower lifting device for a rotary blasthole drill, comprising a hydraulic cylinder (5), an extending oil path (7), a retracting oil path (6), a speed control oil path (14) and a proximity switch (3), wherein the extending oil path (7) is connected to a non-rod-end chamber of the hydraulic cylinder (5), and an extension control unit is provided on the extending oil path (7); the retracting oil path (6) is connected to a rod-end chamber of the hydraulic cylinder (5), and a retraction control unit is provided on the retracting oil path (6); the speed control oil path (14) is connected to the retracting oil path (6), the speed control oil path (14) is connected to a speed control valve block (15) in series and the tail end thereof is connected to an oil tank (16); the proximity switch (3) is arranged on a tower supporting frame (2) for controlling the switching on and off of the speed control valve block (15), and when the tower (4) is approximately in a horizontal state, the speed control valve bl

Abstract: A rock drill telescopic arm is provided having a fixed arm which is sleeved on a movable arm; a telescopic oil cylinder; a plurality of adjusting blocks in the fixed arm along a circumferential direction thereof; a plurality of adjusting screw rods for respectively adjusting the position of each of the adjusting blocks on the fixed arm; a wear-resistant sliding block between at least part of the adjusting blocks and the movable arm; and a retainer at an opening end of the fixed arm for preventing the wear-resistant sliding block from moving along a telescoping direction of the movable arm, wherein the movable arm can be driven by the telescopic oil cylinder to slide along the wear-resistant sliding block. A rock drill equipped with the rock drill telescopic arm provides for convenient adjustment of a gap between the fixed arm and the movable arm.