Three New Ways to Speed up Handling
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Latest B. B.S. Designs Include 3-ton Parcels Van, Three-piece Demountable Platform Body for Eight-wheelers, and Slave Tractor with Variable-height Fifth Wheel THREE new vehicles were demonstrated by British Road Services at their Cressey Road depot, Hampstead,. London, on Monday. All have been developed to, facilitate the handling of goods in bulk and to speed up transit.
The vehicles consist of a-3-ton parcelsdelivery van,. an eight-wheeler with three removable body sections and 'a shunting tractor with hydraulically operated fifth wheel Each is an •experimental 'prototype. .
Known as the VA van, the new parcels Vehicle is based on a standard Austin 11-ft. 6-in.-wheelbase forward-control chassis,. powered, by a B.M.C. 34-litre four-cylindered 58-b.h.P. oil engine. The steering-column rake has been altered. however, and the pedals have been set back 11.in., so that the line of the driving sea :t now lies, behind the wheel-arches, thus giving a " walk-through " cab layout.
Good Engine Access
A small external bonnet has been necessitated by this modification. It is a quickly detachable plastics moulding, which in turn serves greatly to improve engine access. Deep windscreen panels give good forward visibility and sliding doors, which can be hooked back in the open position, are fitted to both sides, of the body.
The van has a 500-cu.-ft. body and its overall length and width are 19 ft. 6 in. and 6 ft. 6 in. respectively. The body is of composite construction, with a fullwidth translucent Plastics panel in the roof, and the rear is closed by a tailboard and half curtains. Provision is made for installing a roller shutter for use on certain services. The body floor has small wheelboxes, and the rear loading height is 3 ft. 3 in.
There is a partition with a sliding door behind the driver, and above the cab is a small lockable compartment that can be reached only from the van interior.
A 5-ton version is at present being developed by B.R.S. This will have a 750-cu.-ft. body and aS•ovetall width of
c6 7 ft. The bonnet of the 5-tonner will be longer than that of the 3-ton van, because of the longer six-cylindcred engine which will be fitted,
Devised by B.R.S. to handle suitable flows of traffic more economically, the Tripad system of three-piece detachable bodywork was demonstrated on a Leyland Octopus eight-wheeler. The platform body on this chassis consisted of three 8-ft. sections, each capable of carrying 5 tons. Each section weighs about 8 cwt., bringing the kerb weight of the complete vehicle to about 9 tons, but later versicins will have light-alloy sections to increase the payload capacity. .
Each section has slotted side members which allow, the laden " pallets " to be removed by fork-lift truck. Each section is located on the underframing by two pyramid projections. and by transverse triangular members, and these combine to provide automatic alignment when loading. They are secured by means.of screw-actuated clamping rollers, which are wound into place and lock over lugs formed on the section underframes.
Detachable sides and headboards can be fitted to the pallets to divide different types of load, and they cart also be assembled as containers. All the pallets are identical and interchangeable and the sections. may readily be transferred to rail wagons or 'smaller road vehicles, thus quickly' freeing an eight-wheeler for longdiStance work at the end of each journey.
Similarly, individual sections can be removed or added at intermediate points along a /mite, having been loaded before the vehicle arrived. The system Can be applied to a 'variety of vehicle types,
ineludirig.semi-trailers.' S.D. Freightlifter 7-,ton fork-lift truck" was used (hiring the demonstration, which showed how easily the pallets could he removed, interchanged' and reloaded.
Douglas R.R. Tractor The shunting tractor demonstrated. is basically :the pokigla.s.Tugmaster type, Slightly modified to suit the specialized requirements al. B.R.S. The R.H. model is similar to the larger 60-ton-capacity machine developed for °Mel& use and described in The Commercial Motor on April 19, 1957,
The Douglas has been adopted by B.R.S. because, in their 'larger depots, it is frequently necessary to move laden and unladen semi-trailers to and -from loading banks and to parking places. To use conventional tractor units is a lengthy business, as the full coupling and uncoupling operation has to be gone through each time, involving retraction and lowering of the semi-trailer landing Furthermore, it reduces the availability of serviceable motive units for normal haulage work.
It was found desirable, therefore, to have one-man-operated "slave" vehicles solely for handling such semi-trailers. To do this without the bother of operating the landing gear on each occasion, the tractor had to be .fitted "with a hydraulically elevated fifth-wheel coupling. This decided the choice of the Douglas Tugmaster, which is now being specially produced for B.R.S. by Douglas Equipment, Ltd., Cheltenham.
The S.A.E. fifth-wheel coupling is mounted on a fabricated sub-frame which is hinged at its forward end, and raised and supported by two 8-ton hydraulic rams. Lateral support is given by side guide plates which straddle the chassis frame.
Power for the rams is provided by an engine-driven pump, and a 12-gal. header tank is mounted within the chassis frame. The lever controlling the ram actuation has three positions: raise, lower, and automatic." When coupling, the tractor is reversed up to the semi-trailer, the coupling is raised slightly above the level of the semi-trailer rubbing plate, and the operating lever is placed in the automatic position.
As the tractor is reversed under the semi-trailer, initial contact between the two units is made by two strips built into the fifth-wheel coupling. These strips operate two valves which release the pressure in the rams and allow the fifth wheel to slide under the semi-trailer plate without the usual shock impact. The levelling strips are designed to close the hydraulic valves when the fifth wheel is between in. and in. clear of the semi-trailer plate.
A cam mechanism maintains an angle of 2° in the lowest position to approximately 10° in the highest position, thus ensuring the most suitable angle for each height of semi-trailer, and reducing the shockloading on the king-pin and coupling gear.
When the coupling is locked--this -being automatic—it is raised and the front of the semi-trailer is lifted until the
jockey wheels are about 9 in. clear of the ground. When uncoupling, the fifth wheel is lowered until there is sufficient clearance to allow the tractor to be driven away. Then the coupling is unlocked without the driver dismounting, there being a control lever to the left of the steering wheel.
The tractor demonstrated is powered by a Commer 56 b.h.p. petrol engine, unit-mounted with a Commer four-speed gearbox, only the lower two ratios of which are used. A 7.2-to-l-ratio spiralbevel rear axle gives a maximum speed of about 8 m.p.h. Hydraulic brakes are used, a Clayton Dewandre vacuum servo being fitted, and there is a drum brake on the nose of the rear axle.
Thus, the foot brake actuates the wheel brakes directly and the transmission brake through the servo, whilst the hand lever acts on the rear-wheel and transmission brakes. This gives sufficient braking power for handling a gross train weight of 22 tons without having to connect The semi-trailer brakes.
The tractor has 6.50-20-in. (8-ply) tyres and the rear axle is unsprung. An oil engine may be used in later versions for use in depots where petrol is not readily availa.ble, but low-powered units will continue to be employed, so that there is no risk of a laden semi-trailer being driven up a slope on which the brakes could not hold it. Fork-lift attachments and drawbar gear can be added to the tractor.