A New, More Powerful Farm Tractor T HE name "Cropmasler "
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is given to the range of improved tractors just announced by David Brown Tractors, Ltd., Meltham, near Huddersfield. New features and modifications are not merely detail ones, or of a catchpenny character, but are the result of long and careful development work by skilled engineers, aided by leading_ farmers and agricultural experts.
In the new tractor the hydraulic system for raising implements is situated in front of the gearbox, utilizing the reservoir of oil within the gearbox itself and • feeding the oil under pressure to a ram-cylinder mounted on the near side of the rear axle. Working pressure at the cylinder is 600 lb. per sq. in„, compared with 1,300 lb, on previous power lifts, and the upward lift at the end of the link arms is 1,330 lb., compared with 1,240 lb. on VAK.1A tractors. The Cropmaster thus provides a greater lift at a reduced Working pressure. •
Linkage Further Improved In addition to the change in the design of the power lift, much thought has, been devoted towards improving the details of the linkage, and the following new features are provided,—Robust arid strengthened lift arms and lift rods; large, free-working adjusting levers on the off-side lift arm; and supplementary adjustment on the near-side lift arm.
There is a sturdy ram-shaft connecting rigidly the near-side• and off-side lift arms to ensure maximum rigidity. Implement locks are fitted so that the power lift can now be locked in the "up ", position for transport and in the " down " position for work. A half-way .position is also provided for direct-attached implements the depth of which is controlled from the tractor.
In the Cropmaster the linkage geometry differs slightly from that. of previous designs, in that the tractor end of the top link is fixed to the ram shaft, which, in turn, rotates as the implement lifts or lowers. This ensures that the pitch of the implement shall remain constant. .
The power, unit of the Cropmaster is similar to the successful T.V.C. engine which has powered VAK./1A tractors. Final-drive gears; however, have been completely redesigned and.,strengthehed, the ratio being increased. This provides greater torque at the rear axle and in conjunction, with the redistribution which has been effected in the tractor weight allows an increase of about -10 per cent in the draw bar pull without any rise in'fbel consumption.
The rear axle is offset 2 ins, to the near side, giving better weight distribution on the land-side wheel, in the ploughing position, and consequently minimum wheel slip. Larger wheel guards are now fitted, giving better protection, whilst there is a dual bench seat, affording the driver greater accessibility to his implements. A new parking brake is a simple automatic ratchet device which can be applied or released with one foot movement. The power take-off is now a standard fitment. There is protection for the front steering mechanism, the king-pins being shielded.
All Cropmasters have 9-in. by 28-in. rear tyres, 6-in. by 19-in, front tyres, and magneto ignition as standard equipment. Series 4 models hav't four-speed gearboxes and Series 6 models six-speed gearboxes. All Series S models have electric starting and all, except Series M, have in-built hydraulic lift, standard screw-type top link, and drawplate. All Series M models are supplied without hydraulic lift, drawPiate, or top link, but with general-purpose drawbar.
Prices are. as follow:—Tractor with in-built power lift. drawplate and top link: Cropmaster 4, £433; 4S, f-455: 6, £458; 6S, £480. Tractor without •power lift, top link or drawplate, but with general-purpose drawbar: Cropmaster 4M, £415; 4MS, £437; 6M, £440; 6MS, £462.