Forward Control for Two Dennis Goods Models
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Important Modifications in Two of the Popular Four-wheelers of the Dennis Range
lp ROM the works of Dennis
Brothers, Ltd., Guildford, comes the news that two a the most successful of the company's goods carriers, the two-tonner and the sixtonner, are now available with forward control. This information, which we are in a position to announce exclusively, will be welcomedby the many Dennis owners in this country and abroad, for the innovation offers the advantage of additional body length for a given wheelbase. We have seen and handled the new Machines at the works, and were glad to note that, by careful design, accessibility has been well preserved in spite of the driver's seat being beside the engine.
Dealing first with the new for
ward-control two-tonner, this has an engine similar to that in the standard chassis, but modified in that the valves are placed at the side. It has four cylinders of 85 mm. bore and 120 mm. stroke and develops about 40 b.h.p. at 2,300 r.p.m. Aluminium pistons are specified and a slightly altered induction manifold is now incorporated, this .being of the straight type with a hot spot. The carburetter is placed on the near side, and the magneto, which is gear-driven, is close to it. Two Whittle belts are employed to drive the fan and the dynamo, the. latter component being located below, an just behind, the radiator.
Transmission Unaltered.
The gearbox, which forms a unit with the engine, is the same as in the normal-control chassis, and the same type of torque tube, with roller steady bearing, encloses tI4 propeller shaft, the ratio of the overhead-worm final drive being 7.5 to 1.
The standard wheelbase for the normal-control two-tonne.r was 12 ft., but the forward-control machine is available with a wheelbase of either 10 ft. or 12 ft. In the case of the shorter model, a frame length of II ft. 21 ins, is available for the mounting of a goods body. The braking equipment is im4 changed, braking being concentrated upon the driving-wheel drums, each of which contains four quarter-circular shoes lying in the same plane. Two shoes in each drum are operated by foot with the • aid of a Dewandre vacuum cylinder, the other two. shoes
being actuated by hand lever. The brake drums are 17 ins. in effective diameter and 3 ins. in width, and as each shoe is 11 ins., long, the aggregate facing area is 264 sq. ins.
In the forward-control model the ,
brake, clutch and gear controls are carried on a cast bracket rigidly bolted to a lug on the top half of the crankcase, the gear lever being! operated by the left hand. The lever is ball-mounted and operates through a longitudinal shaft ,,vhih has a ball joint at each end. Four forward speeds and a reverse are provided.
The steering is of the cam-androller type, the box being mounted on the off-side dumbiron, with a drop arm on the right and the drag link is short. Theihand-brake bracket is simply bolted to the frame member. A 15-gallon fuel tank is mounted to the left of the driver's seat, just -behind the engine. The turning circle is, we understand, to be standardized at about 40 ft. The forward-control model is available at 1420—the same as the standard two-tonner.
In the ease Of the 6-ton chassis, 125 extra is charged for the new model arranged for forward-control, hut certain additional equipment is included, notably vacuum-operated rear-wheel hrakes. There is no -alteration in the engine, the fourcylindered 70 b.h.p. unit of 110 ram. bore and 150 ram. stroke being retained. .The gearbox, however, is bigger in all working dimensions, thus reducing the load on the gearwheel teeth. The main and layshafts are 21 ins. in diameter, and
the constant-mesh pinion is carri& between two bearings. The trans mission is unaltered, the final-driv( ratio being 8.75 to I or, alternatively 9.66 to 1.
Two lengths of wheelbase arf available, each being 7 ins, less than the wheelbase of the standard:controI models. With a wheelbase of 13 ft. 7 ins., the measurement from the back of the cab to the end of the frame is 15 ft. 8 ins., and with a wheelbase of 14 ft. 11 ins, the measurement from the cab to the frame end is 17 ft, Arrangement of Controls.
On the six-tonner a bracket for the right-hand gear lever and brake lever, is bolted to the frame longitudinal just behind the mounting for the clutch and brake pedals, which are on a common cross-shaft passing through bosses on the frame member. A short transverse shaft in the gear-lever bracket makes provision for the gate-type of gear change, there being a ball joint on the lower extension of the lever and two universal joints on the longitudinal shaft, which leads to the selectors mounted on the offside face Of the gearbox.
Steering is ' of the worm-andsector pattern, and the steering box is mounted above the frame, just below the floorboards, providing an almost vertical steering column. The turning circle for both lengths of wheelbase is a little less than 60 ft.
The Dewandre vacuum cylinder is conveniently located between the frame members, behind the gearbox and before the cast cross-member which, in this model, takes the thrust and torque.
A new kind of brake drum is fitted to. each. rear wheel, this providing increased friction area and rigidity. It has an effective diameter of 211 ins., and is strengthened by a thick flange around its periphery. The effective width is no less than 51 ins., and, in this drum, two Ferodo-faced shoes operate.
This chassis has a very powerful transmission brake, the drum, which is behind the gearbox, being 12 ins, in diameter and 6 ins, wide.