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).
Production inspection and test specification for a 20 HP starter motor switch.
| Identifier | ExFiles\Box 56\4\ Scan082 | |
| Date | 18th October 1926 | |
| X5650 18.10.26. X.5781sw. STARTER MOTOR SWITCH. X.5650. 20 HP. SPECIFICATION OF PRODUCTION INSPECTION & TEST. Remove top of switch and (1) Ascertain:- (a) That the lever moves easily on its pivot. (b) That the contact fingers are flexible, contain no rough edges or burrs, are not twisted, and in general are likely to bed well on the plunger. (2) Confirm the absence of excessive friction between the plunger and the guide pin, and between the plunger and the case. The plunger (with the spring removed) should be lifted and allowed to fall several times in different positions rotationally, it being confirmed each time (by means of a lamp and battery) that the plunger has made contact with the inner spring fingers and not the outer spring fingers. (3) Now make a test for the contact pressure of the fingers on the plunger, and for excessive friction between plunger and the guide pin, when the plunger is pushed right down. In order to do this, a spring balance may be connected to the plunger by means of an attachment to the nut. The forces required to pull out the plunger for four positions 90º apart, both with and without the spring tube in position, should be observed. The readings may vary according to the position of the plunger, due to slight excentricities, but there should be no material Contd. | ||