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).
Issues with Kelloch brakes and proposing new schemes for hydraulically operated brakes to prevent fluid leaks.
| Identifier | ExFiles\Box 179b\1\ img125 | |
| Date | 24th October 1932 | |
| HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} ORIGINAL R2/M24.10.32. 41559. C to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} BY.{R.W. Bailey - Chief Engineer} DA.{Bernard Day - Chassis Design} re. HYDRAULICALLY OPERATED BRAKES. DA.{Bernard Day - Chassis Design} has hunted this matter up very thoroughly, and finds that the Kelloch brakes have all manner of gadgets and valves to prevent a leak past the rubber plungers. Unless we cannot do without these I should not advocate the use of this system. I think however we can give a much more satisfactory scheme for preventing the fluid passing the piston, in fact, we are in quite a different position to the Kelloch, who generally put their cylinder and piston right inside their brake drum. In the meantime we will keep the wholly mechanical operation moving as it may win in the end, but there is no doubt that there are many advantages in the hydraulic, of more perfect equalising, greater efficiency, with the possibility of automatic adjustment. (1) In the schemes that I have devised for preventing any ill-effect from the oil gravitating through the operating cylinders one can see the possibility of the master cylinder closing its connection to the cylinders at the end of the stroke. (2) We also schemed long ago a method of putting a metal piston ring under the packing on the piston so as to give an initial tightness for low pressure operation. (3) We can also see the possibility of including in each operating cylinder a continuation of the operating piston to a small dia. pump which will clear out any leaky oil that has passed the piston during the operation of the brakes. We can also see that the engine vacuum could be used in a separate little chamber in the main reservoir in such a way as to suck up all the oil that has gone to the operating cylinders and passed the pistons. This would be nominally closed with the main reservoir but would be opened by the operation of applying the brakes, and would then gravitate into the main reservoir tank. Some one or two of the devices here mentioned might cure any trouble of loss of oil, but the parts should be made in the very simplest form in the first instance, and only such complications applied that force themselves upon us. R.{Sir Henry Royce} | ||