NEW TRACTOR-LORRY CONVERSION SETS.
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By the Use of Two-Wheeled Trailer Attachments Any Ordinary Four-wheeled Vehicle can be Converted to a Six-wheeled Tractor-lorry.
THE enterprising makers of the wellknown Carrimore trailers., Carroeserie Latymer, Ltd., are always well to the fore in bringing out improvements to trailers or trailer attachments. Their. latest example of the latter type is a two-wheeled carrier attachment by which an ordinary four-wheeled lorry can be converted to a six-wheeled tractor-lorry.'
In the case of a short-wheelbase machine, such as the ton Ford, the carrier attachment takes up the whole of the' loading space and provides a body which can be considerably longer than that which could be fitted to the Ford in the ordinary way and which, in addition, can carry a load of 30 cwt. without imposing additional load on the Ford rear axle. There is no particular limitation as regards the size of the body utilized. This can be made to suit individual requirements.
In the example which we illustrate as attached to a Ford ton truck, the capacity Of the body is 320 cubic ft., and part of this large eapacity is obtained by providing a deep well under the body stretching froni the rear for about twothirds of its length. When required, the axle of the trailer portion can be cranked, thus permitting a body with a loading line of 17 ins, from the ground.
A particularly interesting point about the outfit is the arrangement of the. braking. External contracting band brakes operate on drums attached to the trailer wheels, and the action of these is balanced by a sliding bar supported under the frame of the trailer. The pullon wire is carried through the hollow spigot of the turntable, under and over suitably arranged pulleys, as shown in our illustration of the spigot, and is connected to the hand brake lever of the Ford, or any other vehicle to which the i attachment s fitted, and it is so ar ranged that; the leverage exerted on the brakes of the trailer as rather greater than that exerted on the brakes of the vehicle, so that there is a slight tendency
for the trailer to-pull against the vehicle, or what might be called the tractor portion, thus the whole outfit tends to straighten out, instead of the trailer swinging round, as might.happen if the brakes of the vehicle were applied before or more strongly than those of the trailer.
_ The turntable is stoutly constructed from two pieces of angle steel, each bent into the form of a circle and welded. The circles are thoroughly well braced by cross-members, and the whole turntable is pivoted at each side on strong brackets bolted to the frame.
In the case of the machine we examined, the original holes for the body on the Ford frame were utilized for this purpose, and thus no weakening of the frame ensues. The side brackets are additionally strengthened by stays.
At the front of the turntable are two vertical pins, pivoted to the turntable at their upper ends and carried through brackets attached to the frame aide members. Stout square-section spiral springs are fitted to these pins above and below the brackets, and thus the turntable
floats. It is unnecessary to pivot the latter in both directions, as any tendency for the trailer portion to twist in relation to the vehicle is taken up by the rear springs. The attachment is thoroughly well made and well finished. It is rounded at the front in order to allow for the movement when steering, which, incidentally, can be as much as 90 degrees, and is made with a detachable tilt, whir:J.1 includes the upper portion of the rounded front, and, When moved, leaves a lowsided lorry body.
The .driver's cab is provided with a false back, curved to follow the contour of the front of the trailer. This leaves a space between the driver's seat and the rear of the cab, which space can be utilized for the carrying of spare wheels, tools, etc.
The trailer springs are long and supple, the rear ends being arranged to slide. The trailer frame is constricted B27
of pressed-steel channels, and each spring is carried On 61 subsidiary frame, constructed of angle steel, with stout gusset plates.
Several interesting developments of this trailer adapter are wider construction. It will be realized that if adapters of this description were fitted to the rear of an ordinary lorry there would, if no other body were provided, be a considerable loss of loading space on the lorry itself. Therefore, the company have adopted a novel method of undercutting the body of the lorry and fitting a turntable immediately Over the rear axle, under the projecting portion of the body. The end of this portion is rounded, whilst the front of the trailer Or carrier portion is made concave to sent the convexity of the body on the vehicle. The latter can be fitted with side doors, and the whole forms a most convenient unit, which, whilst being considerably shorter than the ordinary vehicle and trailer, has far more body space.
The method of braking is the same as that utilized on the adapter set which we have previously described.
The number of two-wheel attachments need not he limited to one, as the vehicle can be quite easily detached and utilized with other trailers. Where this is specifically arranged for, each trailer is provided with two hinged legs, fitted at the :front end. These legs are fitted with screwed feet, which act as jacks, by which the front of the trailer is lifted clear of the lorry, when it can be unloaded or loaded at leisure while the lorry is dealing with other trailers.
Special arrangements are being made by which it will be unnecessary to dieconnect the turntable. At each side of the latter will be a straight member, carrying four rollers. The front of the frame of the adapter will be splayed out to bear on the rollers, and, if necessary, these side members can be curved, so that, as the lorry is run back into position, the front of the attaehment is lifted clear of the ground. The turntable can then be locked into position by means of an ordinary spring lock, and ordinary locking pins will be inserted at the front end.
It will readily be understood that, except for the additional work thrown on to the vehicle in order to haul a heavier load of goods, none of the parts is stressed further than would be the case if an ordinary body were fitted; what extra load is carried is borne on the rear wheels of the trailer portion, and in some eases it is probable that the load borne by the rear wheels of the vehicle will actually be less than formerly, particularly as the well is not carried forward for the -whole length of the body.