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).
Proposed modifications to self-adjusting tappets for the J.2 unit.
Identifier | ExFiles\Box 106\5\ scan0077 | |
Date | 30th November 1932 | |
X5060 RHC.{R. H. Coverley - Production Engineer} From Hs{Lord Ernest Hives - Chair}/Mths.{Reg Matthews} Hs{Lord Ernest Hives - Chair}/Mths.{Reg Matthews}5/MA.30.11.32. J.2 UNIT. SELF ADJUSTING TAPPETS (Lec.3213). We wish to try the self adjusting tappets on the J.2 unit now on the test bed but would like the existing set modified to the following:- (1) Longer Plungers as shewn on Sch.2 (Lec.3213) (2) Flat wire springs as used at present. (3) All Plungers to be made without Labyrinth grooves. (4) Plungers should have .001 dimetral clearance. The last item is very important as too large a clearance makes the tappets noisy owing to the continual leak of oil past the plungers, but on the other hand if the clearance is too small there is a tendency for the valves to remain open when the oil gets hot owing to the plungers not adjusting themselves for the increase in length of the push rods. There is also a risk of the plungers seizing if the clearance is too small this has happened on one or two plungers in which the clearance has been much less than .001. The working limit of the plungers should be as fine as possible. Hs{Lord Ernest Hives - Chair}/R.Matthews. | ||