Downhole drill thrust measuring device

The invention discloses a downhole drill thrust measuring device connected between a drilling plug pipe column and a drill. The measuring device comprises a center pipe with an upper joint and an outer cylinder with a lower joint, the center pipe is installed in the outer cylinder, and the upper joint stretches out of the outer cylinder; a cylinder cover, a piston and an anti-rotation locking ring used for preventing the center pipe from rotating are arranged in the upper portion, the middle and the lower portion of a cavity of the outer cylinder respectively, the cylinder cover is in threaded connection with the inner wall of the outer cylinder and is in sliding connection with the center pipe, and the piston and the center pipe are connected through threads and can slide relative to the inner wall of the outer cylinder; a pressure oil cylinder is formed by airtight space defined by the outer cylinder, the center pipe, the cylinder cover and the piston in an enclosed mode, and the pressure oil cylinder is filled with hydraulic oil; an electronic pressure gauge is installed on the cylinder cover and used for measuring pressure of the oil in the pressure oil cylinder. The downhole drill thrust measuring device is simple in structure and convenient to operate, and actual thrust at the drill can be obtained according to the product of the difference between the intensity of pressure in the pressure oil cylinder before the drill is pressurized and the intensity of pressure in the pressure oil cylinder after the drill is pressurized and the annular area of the piston.