| 摘要 |
<p>Apparatus for fabricating wood structures, such as floor trusses, having an elongate bed supported above the floor on which wood members are held in position for being secured together by nailing plates to form a truss or the like. Tracks extend longitudinally along the bed and a press having a lower platen below the bed and an upper platen above the bed is movable along the tracks on rollers journaled on the lower platen. The platens extend transversely across the bed and are selectively operable to open and close for driving nailing plates into the wood members. The press as it is moved along the tracks is subject upon acceleration and deceleration to longitudinal forces above and below the tracks. The press is so structured as to have its center of gravity generally at the level of the rollers whereby the moments of the resultant forces about an axis at the level of the rollers are substantially equalized so as to substantially eliminate the tendency of the press to rock on the rollers as it is accelerated and decelerated.</p> |
