Abstract: This guidance system for an automatic welder includes a probe, sensing means in the probe, feedback means from the probe to actuating means and appropriate motors and switches to cause the welding unit to move in response to signals from the probe.The probe has a casing with a concentric actuating rod. The actuating rod is supported in the casing by means of a pivot plate which is movably mounted on a fixed plate. A probe finger is attached to the lower end of the actuating rod. The upper end of the actuating rod passes through a series of switches. The switches sense movement of a pivotably mounted actuating rod in a horizontal and vertical plane. The switches themselves are paired and are mounted along planes which are perpendicular to each other.The probe is mounted at a 45 degree angle. Additional switches provide a means for biasing the probe for movement in a given direction without receiving any external signal. An optional switching system may also be used for two speed travel of the entire unit.

Abstract: Apparatus for guiding a welding torch, slave mechanism or the like, including a probe or guide wherein the torch follows or traces the path of the probe, both as the probe (1) follows a basic straight, curved, or otherwise changing spatial or three dimensional path and (2) as it departs from the direction of the basic path or seam because of defects of rather short duration, or of sudden changes in lateral and/or vertical abutments or surfaces against which the probe travels, wherein the path of the welding torch or slave mechanism is caused to trace the path traveled by the probe or guide, and not merely to duplicate the path in a stepwise functional relationship therewith.

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.