DEVELOPING THE CARRIMORE TRACTOR-TRAILER.
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A New Type with Tiller-steered Trailer Wheels and Arrangement for Separate Steering Control for These When Required. A Worthmore-Carrimore Outfit.
FE'MAKERS have contributed so extensively to the development of trailers for use with tractor-trailer combinations as Carrosserie Latymer (1915), Ltd., of Pamber Street Works, Weimer Road, London, W. 10. " They have already built, many practical types, which are giving eminently satisfactory service. Their latest model is particularly interesting. It is built by iarrangement with the patentees, and s applicable to prime movers of any tonnage up to the maximum legal limit, and propelled either by steam or petrol.
The particular example which we examined is applied to a light Ford chassis, and the manceuvrability of the whole machine is really remarkable, whilst it has the advantage that the two wheels of the trailer portion may, when required, be steered independently of he tractor, so that while the latter is stationary:, the trailer may be moved to any angle in relation to it.
The vehicle has been built to a special order, and is required for use on narrow mountainous tracks, where obstacles fre
quently recur. The body is supported on two turntables, one on the tractor and the other on the frame of the two. wheeled trailer. In the Ford type the plates are fitted in the ordinary manner, but in larger models they are made larger and are clipped together in order to give lateral stability. The provision of a turntable at the rear enables the two wheels at that end to be turned with their axle. The frame carried on this axle is provided with a lozgitudinal shroud, in which slides a long tubular tiller, pivotal)/ connected at its front end to an extension of the frame carrying the turntable of the tractor. The tiller is permitted to slide in the shroud, and as the vehicle turns from the straight it is drawn.out in proportion to the angle of turn, at the same time turning the trailer axle in such a way that its wheels track with those of the tractor.
If at any time it is desired to steer the trailer wheels by hand, the tiller is disconnected from the tractor by withdrawing the locking pin, the tiller being then .rushed back into the shroud until it projects at the rear, when it forms a lever by which the trailer axle may be turned. It mist be emphasized that the tiller is perfectly free and does no work other than that of steering, the pull being takes through the king pins of the two turntables.
Great care has been taken with the method of operating the brakes on the
third axle. The arrangement is quite novel, although the parts utilized are all designed to follow accepted practice. The rise and fall of the axle and. brake parts and the rearward movement of the unit under load (due to the action of • the springs) are compensated for in the angle at which the pull-on rod operates, whilst the brake cable is arranged round the constant centres of the tractor and
trailer axles. At the front end, the cable is carried through a phosphorbronze eye over the rear cross-member, thence over a pulley, which swivels on the rear turntable spigot.
The upper portion of the front turn. table frame is covered with strip brass, in order to prevent any danger of the cable being frayed.
In the actual vehicle which we illustrate, the steering tiller is extended to the rear, in order to meet the requirements of the purchaser, but in the ordinary tsrpe the tiller in no circumstances extends beyond the rear turntable. Both of the turntables are spring balanced,. and although our photographs show the springs at the rear of the front turntable, they are being moved to the front in order to avoid any danger of interference with the brake cable.
The arrangement of rear steering is also being 'constructed with Ackermantype steering heads' to the trailer axle. An interesting point in this connection is that there is no possibility. of wrecking the joints, as when the :tiller reaches a certain angle with respect to the tractor. it merely 'slides through its shroud and no longer operates the rear wheels; in fact, after the tractor stands at an angle of 90 degrees in relation to the trailer, the wheels of the latter begin to return to the straight. .
One of the benefits of the hand steering arrangement is that, when necessary, it can be used with the whole vehicle in motion, and is then employed for giving an artificial and excessive lock to the rear wheels when the conditions necessitate this being done.
The Worthmore Motor Co., 34, Victoria Street, London, S.W. 1, have recently turned out an interesting tractorlorry combination utilizing a Carrimore trailer unit. The Leyland chassis employed as a tractor has been specially designed by the manufacturers for use in conjunction with the attachment. It is fittedwith an unusually powerful engine, which is actually of the type employed on Leyland fire-engines. It also has a special gear ratio and very short u heelbase.
The vehicle is provided with an insulated van body, 22 ft. 6 ins. long, 7 ft. 6 ins, wide and 6 ft. 6 ins, from floor to roof, and in addition there is a well measuring. 14 ft. 5 ins, by 5 ft. 8 ins. by 2 ft. 10 ins, deep, which gives the advantage of an extremely low, loading height. The total capacity of the body is over 1,100 cubic ft., and special attention has been ,paid to constructing it sufficiently strong for the roughest work. The vehicle is capable of carrying a net load of 10 to 12 tons, and with this load the mileage per gallon exceeds five—and that with the vehicle running at over 12 m.p.h.—so that the cost per ton-mile of such an outfit is extremely small. Two of these vehicles have already been purchased by Messrs. Edwards Motor Transport, of 17, Oxford Road, Bournemouth, for use on daily services between London and Southampton, Bournemouth, Sherborne, Dorchester, and Weymouth, and have been added to their existing fleet of nearly 20 four-tonners, all of which have been supplied by the Worthrnore Motor Co. It is inter
esting to note that the drivers were able to handle the vehicle perfectly, both as regards forward travelling and manceuvrs in in reverse, after only two days' tuition.
Although the particular tractor described is a specially designed model, any make of four-ton vehicle can be converted by the use of the Carrimore attachment, and both the ViTorthmore Motor Co. and Carros.serie Latymer (1915) Ltd., have various types of tractor lorries in stock, and will always be pleased to give demonstrations.