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).
Letter from Wilcox-Rich Corporation discussing the design and potential improvement of a hydraulic tappet.
| Identifier | ExFiles\Box 158\4\ scan0021 | |
| Date | 27th January 1934 | |
| STD X1360 See me HS{Lord Ernest Hives - Chair} January 27, 1934 Dict. 1-25-34 Mr. Rowbotham, Rolls Royce, Ltd. Nightingale Road, Derby, ENGLAND. Dear Mr. Rowbotham: I enclose a blueprint showing the hydraulic tappet as we now make it. I think perhaps the hole that you thought was a vent hole in the face of the sample tappet I sent you, must have been a defect in the chilled face of the casting or in the applied face if it was made similar to this blueprint because it is not our intention to have any hole there; in fact, the long tube should set down in a pool of oil and it should draw its supply of oil for the tappet from the bottom of that pool where air is supposed to separate it out and were we to put a small hole in the face of the tappet so some of the oil would go out on the camshaft, it would undoubtedly upset all the working of the thing because the hardest thing we have had to do was keep air out of the tappet and surely that would let it in. You said you were working on something over there that you thought might interest us at some time and at your convenience we would be glad to have any details of it that you care to send over. If it is an improvement on ours, we surely would like to make some arrangement so we could get it and put it into production here because in a short time there will be enough of these hydraulic tappets in use here so they will be accepted as one of the orthodox constructions on cars and I think it would be worth considerable now that one has seat rings that will enable cars to be run for 50,000 miles without any valve grinding, to have a tappet that never would need to be adjusted in that same period. Very truly yours, WILCOX-RICH CORPORATION R.{Sir Henry Royce} Jardine V Engineer. copy sent to Mr. Rowbotham, c/o Detroit Athletic Club, Detroit. | ||