A battery operated drag tractor has been designed and built by Scott Electric Vehicles in cooperation with British Railways, and is in service at the Lawley Street Depot in Birmingham. They will eventually replace the horses for hauling drays.
The tractor hauls a payload of 1ton. It is simply backed under the front of the dray to be moved and its rear platform is elevated to lift the front axle and raise the wheels about 6in. The dray can then be towed and manoeuvred into position by the driver. With a dray in tow the tractor has a turning circle of about 24ft. The driver’s seat height enables him to walk on or off the dray without jumping down.
Controls comprise a steering wheel and brake, a three-step controller operating through a `travel’ resistance wound on six formers and a pushbutton elevating control for the platform. The 2hp motor which drives the split rim front wheel through a chain propels the tractor at a maximum 4mph.
The rear platform is raised hydraulically by a hump coupled to the shaft of a separate elevating motor. Power from both motors is supplied by a 24V `Kathanode’ traction battery, with a capacity of 184Ah at 10hour rating. Solid 10 by 4in tyres are fitted on the rear wheels and an 18 by 7in pneumatic tyre on the front driving wheel.