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).
Design challenges with the dipping headlamps mechanism and engine component fouling.
| Identifier | ExFiles\Box 61a\1\ scan0300 | |
| Date | 11th November 1927 | |
| y4555 DA.{Bernard Day - Chassis Design} C. BY/HED. C. Hs.{Lord Ernest Hives - Chair} EAC. 14. DIPPING HEADLAMPS. Referring to N. Sch. 2495 showing the controls for the above, we have made a layout but find that it is impossible to get straight through with the connecting rod from the controls at the rear end to the controls on the front cross member. The rod in question fouls one of the arms of the engine torque re-action damper. The type of torque re-action damper used is that suitable for the tubular engine bearer arms and not the 'I' section type of engine arm, because in the first place we had no specific instructions that you wanted this type to be used, and in the second place we found that the torque re-action damper suitable for the 'I' section type of arm would foul the front axle control damper, so that in any case we found we had to use the tubular type of support arm. We could make the connecting rod to clear the lower arm of the engine torque re-action damper by lowering the controls on the front cross member, but we think that in view of the length of the connecting rod, approximately 4 ft., it would be advantageous to provide a countershaft and lever, so that we could make the connecting rod in two lengths. You will remember that we had a pull rod of rather similar dimensions to the one arranged on N. Sch. 2495 which was used on the exhaust cutout mechanism for the 20 HP. chassis, but the coupling in question vibrated so badly we had to make it in two lengths by means of the central lever. We are looking into the question of providing a countershaft, but so far have not hit upon a suitable place for carrying same. With reference to the part of the scheme shown on N.Sch. 2496, the Works find it necessary in erecting the engine in the frame to push back the engine foot on the tube carrying same. In addition to this the holes in the engine foot are clearance holes, but the tube is brazed in the bracket which is bolted to the chassis frame. It will not therefore be as easy matter to get the two bearings for the small control shaft in question in lines with one another, which means that there is a great liability of the control shaft itself being crossbound in its bearings as the result of slight carelessness during erection. It would appear that this scheme could be distinctly improved upon. | ||