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).
Gearbox lubrication tests, detailing performance over mileage and discussing potential issues and design changes.
| Identifier | ExFiles\Box 16\1\ Scan091 | |
| Date | 28th July 1923 guessed | |
| Oy3-W-7723 -2- The results after 1000 miles were perfect lubrication of the joint and no fall in gearbox oil level. I will report the results after 2000 miles before this letter leaves. A possible trouble is that on a ten percent grade (about) the gearbox oil will flow back into the sphere, but then actually on about a 5% grade the oil flows out past the rear ball bearing on the 3d motion shaft, and any oil lodging in the sphere has a chance of returning to the box, whereas the oil escaping from the ball bearing is lost, so this trouble we think is not prohibitive. An important point is that by actual test the feed only occurs when the 3d motion shaft is running, that is, when the car is running and the joint discharging oil from the sphere, so that there should be no occasion when the feed is in operation without the discharge, or vice versa. Another point is that both feed and discharge pipes being behind the gearbox and not unduly exposed, they should get warmed up and start circulating in winter about simultaneously. I also send you prints showing the assembly and details of the sphere with split trumpet in front and return grooves at bottom. With these changes, 102-CE ran 4300 miles on two guns full of oil in the sphere without external lubrication. We are now using this device on the sphere, although I am sorry to say that I have not yet officially reported it. Oy. M.{Mr Moon / Mr Moore} Olley [Handwritten note] After 2250 miles the sphere is perfectly lubricated and the box has not lost appreciable oil. Half of this run has been up to Canada and back in difficult & hilly country where any overflow of oil from the gearbox would have shown up if it had dropped the oil level. | ||