Hydrosteer

Hydrosteer was the name given by Hydrosteer Limited of Luton, England, (later Cam Gears Ltd) to its automotive power steering system that was first produced in 1961. It was based on a cam and peg system and was characterised by its fully integrated design and variable steering ratio. This configuration provided automotive manufacturers with a fairly simple design modification to provide a power steering option for cars fitted with a conventional cam and peg steering box. It was fitted to several, mainly British, luxury automobiles of the era. Production continued up to 1973, with just over 105,000 units being produced. As a "first generation" assistance system, applications were somewhat varied in their tuning of the many system dynamics to the specific vehicle. The system fell out of use as powered rack and pinion steering systems gained in popularity.

The 1960s Hydrosteer system should not be confused with Hydrosteer Pty Ltd, an Australian company established in 1981 as a provider of heavy truck steering technology in that country.

The Hydrosteer power steering system was fitted to the following vehicles:

Austin Westminster A110 (optional)
Facel Vega II (optional)
Humber Super Snipe Series V (optional)
Humber Imperial
Rover P5 3-Litre Mark 1a (optional)
Rover P5 3-Litre Mark 2 Saloon and Coupe
Rover P5 3-Litre Mark 3 Saloon and Coupe
Rover P5B 3.5-Litre Saloon and Coupe
Vanden Plas Princess 3 Litre Mk II (optional)
Vanden Plas Princess 4-Litre R
Wolseley 6/110 (optional)

The Hydrosteer system was based on a conventional cam-and-peg mechanism, except that the cam is surrounded by the skirt of a piston within the body of the steering box. Hydraulic power from the power steering pump is transmitted directly from the piston to the peg carrier. A spool type hydraulic valve moves along the axis of the cam in response to steering wheel movement, causing oil pressure to be applied to one side or other of the piston according to the direction the steering wheel is turned, and the load on the input and output shafts.

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