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).
Design and functionality of a multi-position electrical switch.
| Identifier | ExFiles\Box 179b\1\ img349 | |
| Date | 14th March 1933 | |
| FROM R.{Sir Henry Royce} ORIGINAL C. to FOR. HS.{Lord Ernest Hives - Chair} HY{Tom Haldenby - Plant Engineer} re. SWITCH. E7/M10.3.33. Sent off 14.3.33. X6139 It will be understood that a switch is a very important part of the electrical equipment, and a fault in it often means a lot of chasing about before discovering what it is, and may be very difficult to put right. The form of contact therefore should be one which does not require delicate adjustment. There is no need to fear tracking as nearly all the controller type switches do not run on to insulated surfaces, but only have an air gap, and the spring contact is supported on a screw stop when off contact. These switches, when they carry any large current energy are usually fitted with magnetic blowouts, then they last in the most wonderful manner. This naturally does not come within our range. For the sake of simplicity I think a single handle is a decided advantage. There will be less pieces to make and more space to get them in. I do not see any objection to the scheme we are considering, of: (1) The first notch giving accessories. (2) Ignition, charge, and press button current for the starter motor. (3) This should naturally give us side and tail lights for twilight running. (4) Would include head lights and all that has gone before. (5) Could cut off ignition and charge, but not head lights - merely an emergency position to meet your wishes of cutting off the ignition, keeping headlights on. (6) Parking lights. (O) All off position. The switch would run round either way. You will still have plenty of things to put upon this switch. First it must carry a little dashboard lighting press button like we have at present, also a connecting socket for the flexible lamp, and a little red light to shew when the ignition is on and the engine not running. (1) | ||