Metriguard Inc.

Peter A Siebold

James David Logan

Ryan D Baldwin

Dean A Nelson

Timothy T Meekhof

James R Allen

Harry E Moore

Wayne P Waldher

Jean M Logan

Nathaniel D Darnall

David E Abbott

The present invention is a wood grading apparatus including a robust 'push' solenoid as a hammer means for impacting a lumber specimen under test. A conventional solenoid coil with stationary magnetic iron pole pieces is combined with a bimetallic armature including a magnetic portion and a non-magnetic portion; said armature is of uniform cross section through the solenoid coil. A magnetic steel portion of said armature is fastened to a nonmagnetic steel portion thereof, whereby the magnetic field may act upon the magnetic portion of said armature and drive said nonmagnetic portion in an outward direction whereby impact or striking action is achieved. The present invention includes said solenoid in a wood grading apparatus whereby physical properties of wood are measured in a conveyor line setting and wood grading is affected by combining sonic velocity and density measurements to determine the modulus of elasticity of the wood object. Sonic velocity in the wood specimen is determined either by reverberation frequency or by rolling transducers that detect the leading edge of a stress wave initiated by said hammer means. A weight measurement means including a horizontal-axis roller lug conveyor chain and a leaf-spring suspension with a load cell means provides for improved accuracy in weight measurement for wood density calculation.

Sonic lumber tester

An apparatus for testing panel products in edgewise shear in which the shear stress is applied in a diagonal direction with a first rotational degree of freedom in a first grip means and a second rotational degree of freedom in a second grip means as a first loading configuration. A second loading configuration is provided in which the second rotational degree of freedom of the second grip means is locked in place and motion is prevented. A third preferred method of loading is available in which shear forces in a horizontal direction through a centerline of a specimen, with the centerline in the plane of the specimen and extending across a widest dimension of said specimen. Control and data collection are under computer control and operator safety is enhanced by a locking guard door which is electrically locked while the various parts of the machine are in motion.

Rail shear tester apparatus with multiple loading configurations

Growing community of inventors

Pullman, WA, United States of America

Peter A Siebold