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).
News release detailing the construction and electrical data for various types of switches.
| Identifier | ExFiles\Box 168a\2\ img361 | |
| Date | 1st December 1937 | |
| INTERNATIONAL TECHNICAL DEVELOPMENTS LTD. NEWS RELEASE No. H.1 F12/37. CONSTRUCTION The housing is constructed of moulded bakelite which is cemented together by heat treatment. The plunger, working on the beryllium bronze diaphragm, is of laminated bakelite and exceedingly resistant to abrasion and shock. The contacts are of copper, silver-faced. This provides the ideal contact metal: pure silver, with a heavy backing of high conductivity copper. The oversized contact area dissipates heat rapidly. All parts are designed with generous safety factors which ensure long life. ELECTRICAL DATA Type A switches are designed for 10 amperes at 110 v.{VIENNA} A.C. or 5 amperes at 220 v.{VIENNA} A.C. Heating and lamp loads are rated slightly higher for the normally closed switch than for the normally open. If direct current is employed condensers should be used when the loads exceed 200 watts. All switches are capable of withstanding momentary overloads. They will operate with any type of motor up to 1/4 h.p. All of the specifications enumerated above can be varied to meet any special application:- The following standard types are available: A1 NORMALLY CLOSED A2 NORMALLY OPEN A3 DOUBLE THROW, SINGLE POLE. Further particulars may be obtained from the sole British and European agents - INTERNATIONAL TECHNICAL DEVELOPMENTS LIMITED, Thames House, S. W. 1. | ||