method and device for measuring the dimensions of an object, in particular the dimensions of a stahlstabes rolling

摘要

1,239,962. Measuring dimensions photoelectrically. BRITISH IRON & STEEL RESEARCH ASSOCIATION. Jan. 6, 1969 [Jan. 4, 1968], No.700/68. Heading G1A. [Also in Division G3] In apparatus for measuring a dimension of an object, e.g. a bar undergoing rolling by forming a shadow image thereof on a television camera modified for line scanning, the image is formed by a pulse of light while the electron beam of the camera tube is blanked off and then the image is scanned by the beam a number of times to produce successive video lines, one (preferably the first) of which is used to measure the dimension. The length of the shadow pulse in the video signal is measured by counting clock pulses and the count is compared automatically with a count previously recorded using a standard bar to give an analogue error signal which may be recorded or used to control the rolling of the bar. Light may be conducted from the source to the object and thence to the camera by fibre optics. A filter is included to eliminate radiation from the bar and a modified T÷pler-Schlieren system may be used to avoid distortions of the image by hot gases.