| 摘要 |
<p>1. A non-contact dimensional measuring process for metallic profiles of the " H " or " l " type comprising a web and two legs each consisting of two half-legs, said process making use jointly of telemetry and the shadow technique and according to which, considering the web on the horizontal, a) the position and the orientation of one surface of the web is determined by performing a distance measurement by telemetry, in particular by optical triangulation, for two points at least situated in different places on the width of said surface, and characterized in that : b) the height of one end of a leg is determined, on the one hand, by transmitting between the two legs a bundle of rays directed toward the inner surface of the leg in such a way that the bundle is partly intercepted by said surface, the other part spreading beyond the end of the leg whose height is being determined and, on the other hand, by detecting, on the other side of the leg, the position of the point of transition between the zone illuminated by the bundle and the zone not illuminated thereby, c) the position and the orientation of said leg is determined by performing a distance measurement by telemetry, in particular by optical triangulation, for two points at least situated at different levels on the outer surface of said leg, d) and the width of the half-leg corresponding to the leg for which the height of the end was determined is calculated on the basis of the data gathered in operations a), b) and c) above.</p> |
