Drive device of electronic differential automatic tracing welding wagon

The utility model discloses a drive device of an electronic-differential automatic-tracking welding tractor, primarily solving the technical problem of a control system with complicated structure, low control precision, high cost price, etc, in the automatic tracking of the existing welding tractor. The essential technical proposal is that the utility model comprises a welding tractor driven by left and right two wheels which are respectively driven by a step motor. A differential controller is connected with a sensor with the characteristic of characterizing the relative location of a welding torch and a weld seam, a differential proportioning device, a PWM circuit and the step motors of the left and right two wheels of the welding tractor. A single chip computer and a differential proportioning device circuit are adopted and combined with the PWM control technology; weld seam deviation information is output in realtime by a single chip computer controller; the differential proportioning device circuit are used to carry out optimal matching on and adjust the speed of the two driving wheels and to realize seam tracking. Therefore, the seam tracking process control system of the welding tractor has simple structure, high control precision, favourable tracking effect, stable and reliable operation as well as strong practicability.