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).
Analysis and recommendations for the distributor, focusing on the lubricating pad, contact plate, and governor mechanism.
| Identifier | ExFiles\Box 168\3\ img158 | |
| Date | 20th April 1939 | |
| -2- Distributor. (1) The cam lubricating pad, as supplied in the first place, was found to be too soft, resulting in it being pulled out of its holder, by the action of the cam, after only a short period of running. A harder piece, similar to that used in the felt washer to D.54399, as used in conjunction with the dynamo bearing, has now been fitted which is in this respect, quite satisfactory. The pad becomes quite dry after about three hours run at 2,000 r.p.m. oil being thrown along the contact lever onto the points. The drying of the pad is probably due to a pumping action as the cam lobe hits the felt pad, coupled with the creeping action of the oil "some of this oil reaches the point". We consider that any advantage gained by the automatic lubrication of the cam by means of an oil soaked pad, is more than wiped out by the distressing effect of oil getting to the contact points. In any case, unless an oil well is provided, the pad will require constant attention in order to keep it oiled. We recommend the deletion of this part altogether, and to lubricate the cam by a smear of Mobil Grease No. at least once every 5,000 miles. (2) On the bench tests the plate upon which the fixed contact point is welded, was found to move under the normal operation of the distributor, decreasing the 'make ratio' from .75 to about .4. This movement is caused by the hammering affect of the moving contact on the fixed contact at the completion of the return action of the finger. Owing to the present position of the locking screw, the required force to resist movement is increased approximately three times. We recommend that the respective positions of the eccentric rivets provided for point adjustment, and the locking screw should be interchanged thereby bringing the locking screw more in line with the direction of force. This will correspond to the Delco-Remy arrangement which is satisfactory in this respect. (3) The body of the distributor is provided with an oil well for lubrication of the governor mechanism, the screws for holding the condenser to the body pass | ||