JPS6457155A - Apparatus for inspecting applied state of primer - Google Patents

Abstract

PURPOSE:To ensure the inspection of the applied state of a primer, which is applied on an opaque material to be covered such as a steel plate, readily, by comparing the received output light of the reflected light from the applied surface, on which lights are projected from a plurality of a light projectors, with a reference level. CONSTITUTION:Primer 2 is applied along the outer edge of a material to be covered 1 comprising a steel plate, on the surface 1a of which primer is applied. A photodetector 4 is held with a manipulator vertically with respect to the surface 1a so that the optical axis of the photodetector is directed toward the primer 2. Four light projectors 3a-3d, which project lights to the primer 2, are held with manipulators around the photodetector 4 in a similar way. The photodetector 4 is moved with the manipulator at the directly rear part of an application device, which applies the primer 2 on the surface 1a of the material to be applied 1. With respect to the output of the photodetector 4, only the frequency components of the lights from the light projectors 3a-3d are made to pass through a band pass filter 13. The output is demodulated and amplified 14 and compared with a reference voltage, which is preset with a setting part 16, in a comparator 15. A control signal is outputted in correspondence with the magnitude of the result of comparison.