| 摘要 |
<p>A machine for stress grading of timber comprising fixed rollers (2, 4, 6 and 8) through which timber to be tested may pass, and movable rollers (14, 16) mounted on a trolley (22). The trolley (22) is movable in a lateral direction in order to bias one roller (14, 16) or the other against the timber as it passes through, thus applying a bending force to the timber. Once the timber has passed through, the machine in one direction, it is reversed and run back through the machine, the trolley (22), on this reverse traverse, being moved to apply the other roller (14, 16) to the timber, thus applying a bending force in the opposite direction.</p> |
