| 摘要 |
<p>Apparatus for fabricating wood trusses of the type having lower chord members, upper chord members and web members extending from the lower chord members to the upper chord members. The apparatus comprises two presses each having an upper and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more of the wood members of a truss from above and below, and means for supporting the wood members which are to be joined together by the nailing plates, the supporting means including a plurality of supports and means cantilevered relative to each support for holding wood members with clearance therebelow. One of the presses is mounted on a carriage adjacent the upper chord and the other press is mounted on a carriage adjacent the lower chord for movement of each press along its respective chord into an operating position at a first support for driving nailing plates into the wood members, and for movement in a generally lateral direction with respect to the press sidewise out of its operating position at the first support and into its operating position at a next successive support along its respective chord. Each press carriage is movable along its respective chord independently of the other, and has means for controlling movement thereof including means movable therewith for sensing the approach of its press to its operating position at a support in advance of its arrival at its operating position thereby to initiate deceleration of the carriage and for sensing the arrival of the press at its operating position at the last-said support so as to stop movement of the press carriage with its press at its operating position for driving nailing plates into the wood members.</p> |
