From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Different scheme for hydraulically operated brakes, comparing it to a Lockheed system.
| Identifier | ExFiles\Box 179b\1\ img130 | |
| Date | 27th October 1932 | |
| To ) FROM R.{Sir Henry Royce} HS.{Lord Ernest Hives - Chair} ) PN.{Mr Northey} ) C. to SG.{Arthur F. Sidgreaves - MD} BOK. PN.{Mr Northey} Ec HDY.{William Hardy} ORIGINAL HYDRAULICALLY OPERATED BRAKES ETC X1559. Since writing my last memo., and learning that some of our ideas have been anticipated more or less by Lockheed - (i.e. limiting the release) I have thought out a different scheme, which has some advantages - (1) If the operating piston is always arranged to return to zero, in this zero position the passage from the master cylinder can be closed by a valve of say one half the area of the piston, this being pushed off its seat by quite low pressure oil, so that during periods of rest there would be no oil gravitating down to the operating reservoir. In this case we have to make the auto: adjustment on the operating end of the piston stroke, and it would be loaded with full operating forces, but this can easily be done, and as it works in a well enclosed and lubricated condition it should be quite reliable. (2) I have said (I think) that the master cylinder can close its passage to the operating cylinders when at rest, so that we have a double seal against gravitating losses, and emptying the system while at rest, but we may still have some trouble at light braking, which we propose to reduce by the spring rings under the leather cup packing of the operating pistons. (3) I have no faith in the Lockheed rubber cup, or their fluid for either the hydraulic shock dampers, or brakes. (4) By the use of a return pipe system we can return all the oil that has leaked into the operating chambers back to the master, either by pump or engine vacuum, but doubt if this is worth while. R.{Sir Henry Royce} | ||