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).
Experiments on 'Easy Starting Devices' involving modifications to a standard hand pump.
| Identifier | ExFiles\Box 31\3\ Scan027 | |
| Date | 15th February 1915 | |
| (50 H) (W.W. 927. 9-11-14) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 0821. From Exp. Dept. to R.{Sir Henry Royce} J.{Mr Johnson W.M.} Na.{Mr Nadin} c E.{Mr Elliott - Chief Engineer} c 15th. February, 1915. Wor{Arthur Wormald - General Works Manager}/EH1/D15215. OC 1444 Easy Starting Devices. We have carried out experiments with an arrangement made to Mr. Royce's instructions - a sketch of it is attached. To work this arrangement at all it was first necessary to alter the standard hand pump. With the existing pump it is not possible to pump up more than 5 to 7 lbs. pressure in the small reservoir. This is due to the construction of the non-return valve and to the release at the bottom of the stroke which short circuits the air pass the washer of the pump. What happens is that the non return valve does not close quickly enough and at the bottom of the stroke the pressure leaks out of the release arrangement, if the pump is not worked the full stroke the pressure can be maintained because then the release arrangement cannot work. To make it work we have sealed the cap under the non return valve and filed a groove on the side of the valve so that the air pressure can get at the back of the valve and assist in closing this valve quickly - the groove we filed is only a small one so that the frictional resistance to the air compensates for the spring, if we allow a very slight leak it would do the same thing. On a standard pump there is a hole in the bottom cap so that it relies solely on the spring to close it. Attached is a blue print of the valve which will make this more clear. With the pump as it is now we can pump up to 30 lbs. | ||