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).
Pinion and wheel teeth design, comparing rounded versus sharp corners to prevent jamming and proposing tests on a rubber buffer scheme.
| Identifier | ExFiles\Box 64\3\ scan0127 | |
| Date | 26th August 1927 | |
| Contd. -4- EFC2/T26.8.27. engaging corners of the teeth of pinion and wheel are rounded, and so relatively placed that the resultant force between them lies within a direction of a friction angle on either side of the line of action of the force which is the resultant force of the force due to motor armature, which is approximately normal to the helix, and the longitudinal force assisting engagement. This is on the supposition of the engine being considered fixed from rotation as is virtually the case when only the teazer current is operative. For this reason, we are of the opinion that the pinion and wheel teeth on the entering corners should always be as sharp as available material will allow, so to reduce the chance of a jam. On this No.1 scheme, the corners of the teeth are fairly sharp and as reported, in this 20° case, we have not experienced any jam. In the No.2A scheme which we are arranging on 14-EX the teeth are rounded. No tests have yet been made with the rubber buffer scheme included in the equipment or of the 5° spiral on the chassis. An instruction from you concerning further tests on this No.1 scheme would be appreciated. Would the rubber buffer for instance overcome the follow-up thump ? EFC. | ||