AN INDUSTRIAL TRACTOR Proves Its Merits
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ONE of the first points which strike the critical observer in connection with the Chenard-Walcker tractor and 10-ton trailer is that the two units have been designed and built to work in harmony. In practice the result is that they handle as one rather than as two vehicles. During a recent demonstration by Cheriard-Walcker Tractors, 16-17, Pall Mall, London, S:W.1, there was no sign of "tail-wag" in over 30 miles and the trailer followed perfectly in the path of the tractor, being able to round a bend beside a tram without touching the kerb. The effort required at the steering wheel was very small. These features. are largely due to the towing pillar being mounted: in front of the tractor rear-axle centre line and .to the ability to impose a portion of the weight of the front of the trailer upon the tractor ; this avoids :the need for ballasting the machine. The amount of.The weight transferred is variable up to three tons. The front wheels of the trailer can even be lifted off the ground, the forecarriage locked and the tractor re
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versed, pushing back the trailer in the manner of an articulated six wheeler.
An allied question is that of manceuvrability. In a 26-ft. roadway the vehicle, measuring 34 ft. overall, turned with only two reverse movements and actually effected a complete about-turn in a road of only 17-ft. width. This result could be reproduced by any driver with experience of the machine. Coupling or uncoupling is easily effected. Below the swanneck drawbar of the trailer is a roller ; this runs up the sloping ramp of the tractor when coupling, the junction is made automatically and it only remains for the driver to connect the brake gear and the safety chain. Separation of the two portions of the outfit is just as So far as power was concerned the 44 b.h.p. overheadvalve engine was capable of achieving 84 m.p.h. on the level before the governor functions. Using the five forward speeds the acceleration was good. On Putney Hill two restarts were made; the speed never dropped below 5 m.p.h. and reached 10 m.p.h. at the crest of the gradient. On Wimbledon Hill second gear was engaged when the machine had covered a few yards after restarting on first speed. The load was 9 tons 17 ewt., the total weight being 14 tons 6 cwt. On a gradient of 1 in 20 the speed attained was 10 m.p.h.
Braking was on the rear 'wheels of the trailer and on the transmission or rear wheels of the tractor. The outfit was pulled up in 17 yards from 20 m.p.h. down a gradient of 1 in 20 an a tarred surface. The tractor kept a straight course when braking. When restarting the front wheels of the tractor did not "buck."
At the completion of the demonstration the fuel was measured and it was shownthat the fractalhad consumed petrol at the rate of a gallon for eight miles. During the return journey much traffic was encountered in the region of Putney Bridge.