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).
Visit to the Gear Grinding Co. regarding issues with form grinding the B.50 gearbox layshaft pinion.
| Identifier | ExFiles\Box 112\2\ scan0045 | |
| Date | 13th January 1938 | |
| Copy New for file 1044 BY.{R.W. Bailey - Chief Engineer} c. Da.{Bernard Day - Chassis Design} c. Rm.{William Robotham - Chief Engineer} c. RMO. c. WBG DA{Bernard Day - Chassis Design}/Hdy.{William Hardy}15/G.13.1.38. 828 Gry{Shadwell Grylls} B.111, B.50 and WRAITH. Gry.{Shadwell Grylls} and I visited the Gear Grinding Co., Birmingham, yesterday, to discuss with them the difficulties which they had stated were presented by the form grinding/the 1st. speed pinion on the /of layshaft of the B.50 gearbox. We found on our arrival that they had come to the conclusion that the job could be done without the necessity for any increase of length of the layshaft. The principal reason for the change of attitude was that previously they had considered that the grinding wheel must be clear of the gear before the table of the machine commenced to operate the trip mechanism for indexing, whereas they now intend to allow the table to engage the trip mechanism before the wheel is clear of the gear. This is possible because the actual rotation of the gear for indexing occurs very rapidly during the last 1/8th inch or so of table travel. If necessary a further reduction of the clearance required can be made by reducing the speed of the table. The speed of the indexing motor is independent of the table speed, and so the table will move through a reduced distance during the rotation of the layshaft. We were told that the hydraulic operation of the table functions with almost complete consistency as regards the extent of the travel, no more than a few thousandths clearance being necessary on account of variation due to this cause. As regards the lifting of the wheel out of the work and dropping down to trim, this presents no difficulties, but will, of course, increase the time required for the job. We were told that as a rough guess the normal cost of grinding the pinion might be 6/-, but with the limitations imposed by our shaft this may be increased to 9/-. The difference would not go very far towards the cost of the built up construction necessary to simply the grinding of the pinion. | ||