NON-DESTRUCTIVE METHOD AND APPARATUS FOR CHECKING THE QUALITY OF MANUFACTURED WOOD PANELS

摘要

Method and apparatus for non-destructive testing the quality of manufactured wood panels which includes supporting the panel so as to have a portion thereof is cantilevered fashion. The cantilevered portion of the panel is caused to vibrate so as to include complex vibrations that include both twisting and bending. The vibrations in the panel are sensed providing an output signal that is fed to analyzers and computers to determined from thee bending and twisting vibrations simultaneously induced respectively the modulus of elasticity and shear modulus of the panel. Two different forms of apparatus are illustrated, one of which requires the panel to be stationary while being tested and the other in which the panel moves continuously while vibrations are induced and the induced vibrations sensed. The apparatus includes a weigh station to weigh the panel, apparatus to determine the thickness of the panel, apparatus to induce a vibrations in the panel and apparatus to clamp the panel so as to have a portion cantilevered therefrom. In one apparatus the panel passes through a variable sized window opening that in the opened position receives the panel endwise and in the closed position, clamps the panel, holding it still while vibrations are induced in the panel. In the second apparatus, the clamping mechanism is a pair of counterrotating co-operating endless belts, engaging respectively an upper and lower face of the panel.