Smith Industries Ltd. (the new name for the old established firm of S. Smith & Son) recently showed members of the motoring press around their Research and Development Laboratories at Witney in Oxfordshire. to demonstrate their products for the cars of the future.
The main product at Witney is car heaters, and new ideas in this field include vacuum servo control, replacing cables, linked to air blending heater/ventilator systems giving better control than current water-metering valves. New permanent magnet motors using barium ferrite field magnets instead of wire-wound fields will practically double motor output and drive new high efficiency fans or blower wheels. The whole will be encased in compact and stylish all-plastics casings to be made at a new £1-million plant nearby. The ultimate will be fully automatic heater/ventilator systems linked to air conditioner or refrigerator units, which will hold internal car conditions at a pre-set level regardless of external changes of speed or temperature. These are already in use in some coaches.
Smiths Industries are leaders in the field of printed circuit layouts for car dashboards, and now have a “facia package,” comprising a plastic dash panel with printed circuit wiring, on flexible polyester film behind, the instruments and switches being fitted or removed from the front. One connector block connects the complete instrumentation into the wiring loom of the car.
A new transistorised car clock has been developed, getting its power from a tiny mercury cell. This independent power cell is replaceable, but should last fifteen months. It obviates the problem ol normal battery voltage variation and makes the clock a self-contained package independent of the vagaries of the car’s electrical system.
An entirely new electronic speedometer will be available soon, replacing the electro-mechanical speedometer for commercial vehicle use, which has a solid state relay switching parallel circuits within the instrument to compensate for axle ratio changes. An Impulse tachometer for use on diesel engines is driven from one of several types of generator, and the new saturable core circuitry employed makes this new instrument smaller and more robust than before. Its use of a generator for impulses makes it usable on other revolution measuring applications.
The transmission laboratory at Witney is experimenting with the automation of conventional gearboxes, thus providing an inexpensive form of automatic gearbox. Gear changes are made by a system of cams driven by a reversible motor which also actuates a further cam to manipulate the engine throttle control. A magnetic powder coupling replacing the standard clutch is controlled by the same electronic circuit which is the ”brains” of the gearbox control. A simple but effective improvement developed by the transmission laboratory is a multi-cone syncromesh, the normal pair of syncromesh cones being replaced by three concentric cones giving three times the synchronising torque. This now makes syncromesh a possibility on heavy commercial gearboxes.
Work is proceeding on several alternative systems or cooling fan control to prevent the loss of power by the conventional continually driven fan. Ideas include magnetic particle couplings, viscous couplings and centrifugally unloading couplings. Fan drag will be soon a thing of the past.—L. M.