METHOD OF CONTACTLESS MEASUREMENT OF OBJECT THICKNESS Russian patent published in 1996 - IPC

FIELD: light industry. SUBSTANCE: invention can be used for automation of process of hide sorting. Reference and additional probing radiation beams are directed on to controlled object from opposite sides. Reference beams are located on one straight line. Additional beams are arranged at specified distances from reference ones so that planes formed by pairs of beams lie on one side of controlled object, are oriented mutually perpendicular and cross line formed by reference beams. Radiation beams are reflected from controlled object and form light spots in image planes of optical systems mounted properly on opposite side of controlled object. Coordinates of formed light spots are measured, by measurement results lengths of sections of reference and additional beams from projections on to them of centers of corresponding optical systems to controlled object are determined by triangulation method. Thickness h of controlled object is calculated by formula , where l₀ is projection of distance between centers of optical systems on to line of reference beams: l₁, l₂ are lengths of sections of reference beams from projections on to them of centers of corresponding optical systems to controlled object; l₃, l₄ is length of section of additional beam corresponding to reference beam l₁, l₂ from projection on to it of center of corresponding optical system to controlled object; d_1.3, d_2,4 is distance between directions of reference and additional beams corresponding to l₁ and l₃, l₂ and l₄ (which are set in advance). EFFECT: expanded application field in measurement of thickness of rigid hides under automatic modes, increased precision of measurement by avoidance of errors caused by uncontrolled inclination of object. 2 dwg