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 block (15) is on. By using such a tower lifting device in the present invention, the speed at which the tower is laid down to a horizontal state can be conveniently controlled.

IPC Classes  ?

• F16D 31/02 - Fluid couplings or clutches with pumping sets of the volumetric type, i.e. in the case of liquid passing a predetermined volume per revolution using pumps with pistons or plungers working in cylinders
• E04H 12/34 - Arrangements for erecting or lowering towers, masts, poles, chimney stacks, or the like
• F15B 11/046 - Systems essentially incorporating special features for controlling the speed or the actuating force or speed of an output member for controlling the speed depending on the position of the working member
• F15B 11/042 - Systems essentially incorporating special features for controlling the speed or the actuating force or speed of an output member for controlling the speed by means in the feed line
• F15B 11/04 - Systems essentially incorporating special features for controlling the speed or the actuating force or speed of an output member for controlling the speed
• F15B 11/044 - Systems essentially incorporating special features for controlling the speed or the actuating force or speed of an output member for controlling the speed by means in the return line
• E21B 15/00 - Supports for the drilling machine, e.g. derricks or masts
• E21B 7/02 - Drilling rigs characterised by means for land transport, e.g. skid mounting or wheel mounting

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.

IPC Classes  ?

• E21B 17/07 - Telescoping joints for varying drill string lengthsShock absorbers
• E21B 7/02 - Drilling rigs characterised by means for land transport, e.g. skid mounting or wheel mounting