Process and apparatus for the machine sorting of sawn timber according to strength

An apparatus for machine sorting of sawn timber according to strength, comprising:

• two pairs of clamping rollers arranged spaced from one another for supporting and advancing the timber in a direction of movement;
• a rotatably mounted test roller arranged between said pairs of clamping rollers, said test roller having a shaft which is moveable transversely to the direction of movement of the timber so as to move said shaft against the timber to impose a bending deflection on the timber;
• a setting drive arranged to press said test roller into continuous contact with the timber during the measurement process, said setting drive being controllable;
• means for controlling said setting drive so that the bending deflection imposed by the test roller remains approximately constant during the measuring process;
• a force measuring device positioned to measure a restoring force exerted by the timber on said test roller resulting from said bending deflection, said measuring device including means for feeding signals corresponding to the restoring force measured to a computer;
• means for measuring the natural curvature of the timber and feeding signals corresponding to the curvature measurement to the computer;
• and
• means for measuring the position of the test transversely to the direction of movement of the timber and for feeding corresponding position signals to the computer.