Laser beam guided mine tunnelling shield - has shield mounted detector sweeping area along X and Y axes and objective to focus beam and reveal deviation

摘要

A mine tunnelling shield which is advanced by series of hydraulic pistons, employes a laser beam to control its direction, with a detector/receiver for the beam mounted on the shield. This has an analyser for monitoring deviations along X and Y axes. It has a central opening and a series of photo electric elements arranged in a cross shape to correspond to the X and Y axes. The device sweeps an area to detect deviation from these axes, and gives a warning signal when deviation occurs. It employes a gyroscope and has an objective to focus the beam onto the sectors to reveal the deviation. The device is mounted on rods with screw threads for adjustment in two planes.