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 the Springfield, MA office to Derby, UK discussing issues with a 'grunting' steering column thrust bearing and proposing a new design.
| Identifier | ExFiles\Box 154\3\ scan0066 | |
| Date | 25th May 1928 | |
| X 3682 ROLLS-ROYCE OF AMERICA, INC. SPRINGFIELD, MASS. OYRHF1.R.5.25.28 May 25th, 1928. Mr. Thomas Nadin, Rolls Royce Ltd., Derby, England. Dear Mr. Nadin: RE STEERING COLUMN THRUST BEARING SECTION 7050 [Handwritten Note] Mr. Hives Have you any comment to offer please AHS June 8/28 Complaints have been received of "grunting" steerings. This grunting noise has been traced to the thrust bearing, and its cause is shown in SK-204, attached. For small amplitudes of swing of the worm tube, the balls roll slightly between surfaces A and B (upper sketch), the spherical outer race remaining stationary. With greater amplitudes of swing, the radii of curvature of the ball races are not great enough to allow sufficient relative movement to take place within the bearing, and the outer cage must move on its spherical seat. From the nature of the surfaces, it is impossible to maintain lubrication at C between the cage and its seat, so that this movement takes place in a series of jerks, causing a grunting noise. What we would like to do to prevent this state of affairs is shown in the lower sketch. It will be noted that the outer race is made in two parts which bed together along the surface EE. The outer ball race is ground spherical at D(as in the SKF type self-aligning bearing) allowing all relative movement between the worm tube and outer tube to be taken up within the bearing. From correspondence with Mr. Schubert regarding our present type of bearing, we believe that the difficulty with the proposed type will be a possible overloading of the balls due to wedging between the races. For this reason, we have shown the balls .031 larger than standard. Will you kindly ascertain whether or not Derby looks favorably on this scheme? Very truly yours, r/ R.W. Fuller | ||