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).
Technical notes on the Car Electric Clock No. 301.
| Identifier | ExFiles\Box 164\1\ img030 | |
| Date | 1st May 1931 | |
| Messrs. Rolls-Royce Ltd., DERBY. -1- 1st May 1931. CAR ELECTRIC CLOCK NO. 301. TECHNICAL NOTES. 1. A new large Magnet has been fitted which will not burn out on 12 Volt Supply, this if the contacts are purposely "shorted". 2. We are able to wind the two new larger Magnets to 46 Ohms with a larger gauge of Wire which does not get hot at 12 Volts and therefore, burning out will be impossible. 3. The armature is faced with a sheet of non-magnetic metal to prevent it from sticking from risidual magnetism. 4. The driving wheel is now provided with 90 teeth instead of 60 as before. 5. Back-lash on the actual Mechanism is taken up by a maintaining power which runs for 2 1/2 minutes after the winding action has ceased. 6. The winding action takes place without undue sparking at 12 Volts and the contacts have sufficient rub to be self-cleaning. 7. The Clock fails to wind just below 6 Volts and this without chattering. 8. The Clock is self-starting on current being switched on. 9. A coarse milled disc is provided behind Fig. 12 to enable the hands to be set, but the setting would be made more convenient in the bulk. The Regulator would also be made more accessible. 10. For convenience we have fixed one of our standard terminal Blocks on the back of the case, but one Terminal only would doubtless be desired in the bulk, the other connection being made to the case which would be automatically earthed when screwed or otherwise fixed to the dash-board. | ||