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).
Modified method of engagement for the Phantom III starter motor.
| Identifier | ExFiles\Box 62\1\ scan0335 | |
| Date | 26th October 1935 | |
| Hs{Lord Ernest Hives - Chair}/Wst.1/MA.26.10.35. MODIFIED METHOD OF ENGAGEMENT FOR PHANTOM III STARTER MOTOR. With further reference to our Hs{Lord Ernest Hives - Chair}/Wst.7/MA.7.2.35., we have now completed preliminary tests on the scheme outlined. A standard starter motor was modified by increasing the armature diameter to 3.375" machining it parallel along its length and winding it as per drawing D.74035. The poles were modified to suit and a copper bar field winding 4 1/2 turns per pole wound in series. The pinion was made to slide longitudinally in the armature shaft being operated by a spring loaded plunger through the centre of the armature connected to a solenoid. The solenoid had two windings one of which the operating winding had its negative end connected to the main terminal of the motor so that the operating current passed through the motor. The other winding was connected from the motor terminal to earth and served as a "hold in" winding. A considerable increase in B.H.P. from the motor was obtained as shown on attached curves and the engagement was quite satisfactory. As arranged with E.{Mr Elliott - Chief Engineer} the scheme is to receive design attention with a view to making up a set of units for fitting to a car. Hs{Lord Ernest Hives - Chair}/Wst. | ||