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).
Responding to criticisms of a starter motor design, focusing on bearing lubrication and assembly.
| Identifier | WestWitteringFiles\Q\January1927-March1927\ 81 | |
| Date | 11th February 1927 | |
| TO BY.{R.W. Bailey - Chief Engineer} FROM AJS. Copy to - EFC. EAC.7. STARTER MOTOR. (SLIDING ARMATURE). AJS2/M11.2.27. X7625 In reference to BY/RD's criticisms in BY/RD3/LM3227., we always welcome comments of this kind, and deal with the points mentioned in his memo. as hereunder - (1) We quite realise all that is said in this, and it was considered that sufficient grease would be in the ball bearings to last them for a period equal to that between general overhauls of the whole car, as the starter motor is used for such a very short total time. The plain bearing it was our intention to make of graphite bronze or self lubricating metal: perhaps we have omitted to mention this on the drawing. In view of what RD. says about being open to criticism it will probably be worth while to have an oil hole, which is the simplest way of providing a means of lubricating the bearing, and is not likely to get stopped up with carbon dust except after extremely long intervals, and if arranged as shewn can be readily cleaned. Sketch hereunder indicates the oil hole referred to. [Handwritten notes on sketch] SHOULD BREAK OUT CLEAR OF SHAFT TO ALLOW CLEANING. .156 HOLE THIS OIL HOLE IS SITUATED BETWEEN TWO BOSSES FOR SCREWS SECURING BRUSH HOLDER WHICH LOOKS OUTWARD & UPWARD FROM THE ENGINE USE THIS METHOD OF PREVENTING BUSH ROTATING. DRILLED HOLE .062 SPLIT PIN DRIVEN IN BELOW SURFACE OF BUSH (2) We presume the hindrance to assembly referred to under this item is due to the position of the screws securing the end unit, and if this is all that requires altering we would ask you to arrange 4 of the screws behind the brushes to as indicated on (1) | ||