Self-propelled tractor for welding and cutting apparatus and the like

Abstract

A propelled tractor, for welding or cutting apparatus and the like. The tractor has drive and steering wheels and is adapted to support necessary welding or cutting equipment including a guidance system. The guidance system includes a probe mounted on a slide and adapted to follow a seam, template work path or the like and to respond to denotions therein in proportion to the amount of the deviation. The drive and steering wheels are driven by separate motors. The drive motor is adjustable to a predetermined speed so that a wide range of welding or cutting rates are provided and means is provided to selectively disconnect the drive train so that the tractor may be free wheeled. The steering motor is controlled in response to the probe and steers the tractor to return the probe to a predetermined null position, the turning rate being proportional to the magnitude of the deviation sensed by the probe. The probe also controls the working head, welding head or cutting torch to position it on the work path, welding seam or cut line, respectively. The apparatus may be advanced automatically or manually and, if automatic, preferably is adapted to advance, when used for welding only when welding current is drawn. The apparatus includes structure so that the tractor is positioned via the sensing means to retain any desired space, straddle, etc., position relative to the work path.