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 to Adamant Engineering Co. Ltd. discussing efficiency tests on a Marles steering gear compared to an American 'Saginaw' gear.
| Identifier | ExFiles\Box 28\3\ Scan026 | |
| Date | 18th October 1934 | |
| X4014 Exptl. Dept. HS{Lord Ernest Hives - Chair}/FJH.{Fred J. Hardy - Chief Dev. Engineer}25/KW. 18th October, 1934. The Adamant Engineering Co.Ltd., Dallow Road, LUTON. For the attention of S. Carlton Smith Esq. Dear Sirs, We have carried out some efficiency tests on the Marles type L.7 R.H. steering gear you sent us recently for our 25 H.P. chassis. The results of our tests are shown on the attached curves Ref. Hs.{Lord Ernest Hives - Chair}1556. We have also carried out similar tests on an American "Saginaw" gear of approx. the same size as your gear and which is of very similar design except that it has needle roller bearings on the pendulum shaft. In the case of the American gear we obtained efficiencies lying between 68% and 72% for both forward and reverse operation and are therefore rather surprised at the low efficiency we have obtained from your box. The helix angle of the worm in the American gear is less than in your gear so that this cannot be the reason for the difference. We therefore assume that the low efficiency in your gear is due to the plain bearings on the pendulum shaft. We should be interested to know whether you have had any experience with roller bearings on the pendulum shaft and whether you consider that they do improve the efficiency and are desirable. It is mainly to the low efficiency for forward operation that we object. Would you be able to supply us with a steering gear fitted with needle roller bearings ? | ||