Powered Steering Gear in Production
Page 54
If you've noticed an error in this article please click here to report it so we can fix it.
THE Ross hydraulic link-type system of power-assisted steering is now in production by Hydrosteer, Ltd., Biscot Road, Luton. The present production capacity is up to 500 complete sets per week, but the plant and layout are such that this figure could be increased to 2,000 per week.
There are three main components in the system, these being a rotor-type oil pump, a hydraulic ram and a valve working in unison with the movement of the steering-wheel. In one form of mounting, with the power cylinder lying transversely, the point of anchorage for the cylinder is the axle 'beam.
When the power cylinder is arranged longitudinally it is Anchored to a bracket rigidly mounted on the chassis.
It is always necessary to adjust the ratio of the manual-to-power "feel" to suit the type of vehicle. This is achieved in various ways, the most usual being to fit suitable return springs in the valve, or by altering the area of the reaction rings in the valve.
Hydrosteer, Ltd., have developed a third method through the medium of a ratio arm which, in effect, increases the length of the drop arm so far as the operation of the valve is concerned. Through its aid, the degree of mechanical advantage can be varied according to the ratio of the arm fitted.
At present three sizes of power cylinder are available, the smallest being U-in. bore, the next 21in. and the largest, 21-in, bore. It is considered that this range should meet all normal requirements.
Tests made by the company have shown that full control can still be maintained should a front tyre blow out at speed on a road bend. This safety aspect of the system is engaging the interest of a number of police authorities.
It is understood that one vehicle builder is to fit the system to one model as standard equipment, and that, following long-period tests, a number of other makers will in future offer this powered steering system as an optional extra.