BigPatents India

In the present invention there is provided a device which is useful for measuring height between the floor and the roof of mines, quickly and accurately. It consists of a top tube having a sucker at the top-end. The bottom-end of the top tube is connected by means of a lock nut to a middle tube having measuring scale marked on its surface. This middle tube is inserted into a bottom tube and is held in position by a clamp. A magnifying glass and a torch holder is provided for ease of reading of the measuring scale markings. A bob is provided to check the verticality of the device. The device of the present invention is economical, easy to assemble and dismantle, maintains verticality, provides accurate measuring and easy reading and is a faster convergence indicating device, which is particularly useful for measuring convergence of the roof in a mine quickly and accurately.