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).
Diagram of an apparatus for investigating the contact breakers and magnetos.
| Identifier | ExFiles\Box 36\1\ scan 093 | |
| Date | 6th February 1917 | |
| R.R. 425 B (200 T) (S.C. 536, 15-2-16) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 1547. X. 2918 2919 APPARATUS FOR INVESTIGATING THE CONTACT BREAKERS & MAGNETOS MAGNETO UNDER INVESTIGATION D.C. MOTOR WITH VARIABLE RESISTANCE DRIVING MAGNETO BY BELT CHAIN OR DIRECT COUPLING. 2 TO 1 GEAR AS USED ON ENGINE TO SLOW DOWN BELT OR CHAIN SPEED. IF MOTOR AND MAGNETO AXIS DIRECT COUPLED, THIS IS NOT NECESSARY NOTE: OF THE THREE MEANS OF DRIVING BELT IS LEAST DESIRABLE AND DIRECT COUPLING MOST DESIRABLE. SPARK GAP CONDENSER CONDENSER NECESSARY I BELIEVE TO GIVE SHORTER AND BRIGHTER SPARK. MAGNETO FOR PRODUCING SPARK FOR INSTANTANEOUS VISION. DRIVEN AT HALF THE SPEED OF THE MAGNETO UNDER INVESTIGATION D.C. MOTOR WITH VARIABLE RESISTANCE SO AS TO MAKE THE SPEED OF MAGNETO B EXACTLY 1/2 THAT OF A NOTE. BY SLIGHTLY VARYING THE SPEED OF B RELATIVELY TO A, THE CONTACT BREAKER ON A CAN BE SEEN GOING THRU' ITS CYCLE OF MOVEMENTS AS SLOWLY AS DESIRED. THE SPARK GAP SHOULD BE SCREENED FROM THE EYES AND THE ROOM DARKENED. SGO McCLAY 6.2.17 | ||