JPS6482943A - Inspection of defect due to projection and recess on surface of plywood - Google Patents

Abstract

PURPOSE:To permit the inspection of a defect due to projection and recess on the surface of a plywood without any fail to notice, by a method wherein an inspecting part is brought into contact with the surface of a plywood while moving the plywood to measure the up-and-down movement of the inspecting part by a displacement sensor. CONSTITUTION:An inspecting part 2 is brought in contact with the surface of a plywood 1 while moving the same while the up-and-down movement of the inspecting part 2 is measured by a displacement sensor 3. In order to measure the up-and-down movement of the inspecting part 2 by the displacement sensor 3, the inspecting part 2 is pushed against the surface of the plywood, moving by a tension spring 4 for example, and the up-and-down movement of the inspecting part 2 is measured directly by the displacement sensor 3. An optical displacement sensor, a laser displacement sensor, an electric eddy- current type displacement sensor, a vibration sensor and the like may be employed as the displacement sensor 3. The up-and-down movement of the inspecting part 2 may be indicated in the displacement sensor 3 through a numerical value or a graph.