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).
New scheme for a servo and transmission shaft extension for the Junior Gearbox.
| Identifier | ExFiles\Box 165\2\ img286 | |
| Date | 5th November 1940 | |
| To Rm.{William Robotham - Chief Engineer} c. to Rm{William Robotham - Chief Engineer}/HH. c. to Ev.{Ivan Evernden - coachwork} c. to Rm{William Robotham - Chief Engineer}/RC.{R. Childs} [Handwritten] Rm{William Robotham - Chief Engineer}/RC.{R. Childs} Please arrange. [Handwritten] Ev{Ivan Evernden - coachwork}/Tln.4/JH.5.11.40. [Signature] PL.381 SERVO & TRANSMISSION SHAFT EXTENSION. JUNIOR GEARBOX. We have drawn this scheme to ensure that we shall be able to have a servo on the larger models of the Junior Range should we find it desireable. At the time of the original project PL.232 we thought that the servo would only be used on Rippletto. i.e. with a split prop. shaft. For the Junior Range a gearbox extension with a slip joint on the transmission shaft is required and this involves mounting the servo worm by a fresh method. We have used a scheme where the worm thrust is taken on a broached washer and turned half a spline pitch when in position on the shaft. We should be quite happy about this feature if the washer was only loaded during reverse braking but we have had to allow it to take forward braking thrust in order to get the right direction of rotation for the speedometer drive. If Rm{William Robotham - Chief Engineer}/RC.{R. Childs} can provide us with a speedometer with a drive of non standard direction of rotation, we may alter this feature of the scheme. We have used the Senior Range servo motor because to scale it down would save little weight and we should lose rationalisation. The servo worm and wheel are new and have only 70% of the capacity of the Senior Range pieces. thus the limit of servo capacity is now determined by the worm and wheel. Provision has been made for a drive for Tecalemit chassis lubrication. Another gearbox casting is involved in order to provide support for the servo. To Rm{William Robotham - Chief Engineer}/HH's. copy of this memo. we attach:the original of the scheme, a copy of the worm and worm wheel calculations, a print of Hardy Spicer KR.1100 prop. shaft which shows splines for the slip joint. Will he please return the last. Ev{Ivan Evernden - coachwork}/Tln. Th. | ||