A BELGIAN SIX-WHEELED TRACTOR LORRY.
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Trailer Portion which can be Moved Independently. Braking or Tractor Only.
T"practice of uniting a tractor and a trailer to enable the rear wheels of the former to carry the weight of the forward portion of the trailer is on the increase, and is of considerable interest, although it, must not be confused with the movement to increase the number of load-carrying and driving wheels of the self-contained vehicle.
In the ordinary four-wheeled vehicle it is extremely difficult to obtaia anything like equal loading of the two axles ; in fact, if this were obtained, steering might become more difficult and, as a general rule, at least three-fifths of the load is carried by the rear axle, which reduces the maximum load permissible. An interesting development was the Knox six-wheeled tractor lorry, which originated in America. This was followed by the Scamrriell, a machine of improved construction and design and of British manufacture, and the Deere, also made in this country. At the Paris Salon a somewhat similar' machine was on view, although in an
incomplete state owing to restriction of available space. The machine in question was the Renault six-wheeler. The interesting point about the Renault design is that the load-carrying portion of the outfit has a small, pair of front wheels, which are automatically lifted from the road as the tractor portion is reversed into its correct position in relation to the trailer portion.
We have just feceived particulars" of a six-Wheeled vehicle to carry 7 ton loads, manufactured by Auto-Traction S.A., 7, Rue Biart, Anvers, Belgium, which is built on somewhat similar lines to the Renault machine in that it is arranged so that the rear portion of the vehicle forms a four-wheeled wagon when not need with the tractor.
Also, when the trailer is 'used in conjunction with the tractor, the auxiliary front pair, of wheels of the trailer per firm is lifted clear of the ground. The coupling is accomplished in a few momenta by a patent system, which automatically lifts these . -wheels.
An obvious advantage obtained by using this method is that the tractor can be used with any number of trailers. The flexibility of coupling permits travelling over the worst roads without straining any portion of the outfit, and, as with all six-wheeled machines of this
type, the weight of the load and of the vehicle itself is more evenly distributed over the six wheels.
The six-wheeled vehicle manufactured by Auto-Traction S.A. has been tested
for about a year, and is stated to have given very satisfactory results. The trailer can be made in all the ordinary shapes and sizes, including the
unclergung type, which latter greatly facilitates loading and unloading.
Dealing with the tractor, the engine, which is of the Minerva sleeve-valve type, is rated at 20 hp., and has four cylinders of 90 mm, bore and 140 mm. stroke, automatic lubrication, and ignition by 11.4. magneto. The gearbox and clutch form a unit with the engine, the whole being three-point 'suspended. Cooling is effected by a large
capacity radiator with removable sections, which can be replaced without dismantling the whole radiator.
Tine body of the radiator is made in galvanized gieet steel,. whilst the sections are *f copper tubes. The clutch is of the multip!e dry disc type, and the transmission is by selective sliding gears., .providing four speeds forward and a reserve, the change speed and brake levers being centrallypositioned.
A somewhat novel construction is employed for the frame, which is built in two distinct parts, the front, which supports the power plant, being of pressed steel, whilst the rear is of cast steel, apeesially shaped to receive the forward portion of the trailer. The two members are connected by means of a tubular bar, which forins a fulcrum and. allows the chassis to bend horizontally. The front and 'rear parts of the chassis are held (in line by means of semielliptic springs, which are fixed rigidly on the rear portion. The idea, of this suspension is, first, to serve as a shock absorber in case of sudden stopping and starting arid, secondly, to absorb road shocks when the rear of the chassis is unladen.
A somewhat unusual feature in this type of vehicle .i5 that the rear axle is of the dual type, in which there is a load-carrying member of round steel and a separate driving member, the final drive being by internal gears.
It appears from the description that we havereceived that no brakes are fitted, to the trailer wheels.