Patent · US Expired

Transverse vibration apparatus for grading wood panels

US4722223A · kind A · utility

7Cited by
2References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 6, 1986
Grant dateFeb 2, 1988
Priority date
Expiry dateMay 6, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N3/303
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The present invention provides an apparatus and method for establishing a measure of the modulus of elasticity of a wood panel. The apparatus comprises a support frame having a triangular array of panel support points provided thereon. A load cell, in combination with one support point, is interconnected to a frequency counter. This assembly is functional to determine the weight and vibration frequency of a dropped panel. A panel lifting assembly is provided to raise and drop the panel, thereby causing it to vibrate at its natural frequency. In a process aspect, the invention involves supporting the panel at three triangularly arranged support points, raising the panel at the apex end, and dropping the panel to cause it to vibrate at its resonant frequency, and computing a measure of stiffness from the measurements made.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.