| 摘要 |
<p>635,844. Automatic speed control systems. GENERAL MOTORS CORPORATION. June 18, 1947, No. 16056. Convention date, July 3, 1946. [Class 38 (iv)] A device for synchronizing the speed of prime movers comprises two rotatable members, one being driven by the prime mover to be synchronized and one by the other prime mover at the desired reference speed, one member having a simple contact which connects successively with three contacts on the other member during relative rotation, -such that a condenser is charged, and then discharged to actuate selectively a servo-mechanism to effect a corrective change of speed in the prime mover to be synchronized. In Fig. 2, rotating member 20 having a single projecting contact 20a, is rotated either directly, or by means of a tachogenerator and motor, by an aircraft engine. Condenser 18 is connected between earth and contact 20a by means of a slip ring. The other rotating member 19 has three contacts 23, 22 and 24 which are connected respectively to a battery 16 and relays 13 and 14 which selectively control a servomotor controlling the propeller pitch-change mechanism governing the speed of the aircraft engine. Member 19 is rotated at the desired reference speed which may be determined either by a speed controlled electric motor, or by another aircraft engine. If the speeds of member 19 and 20 depart from synchronism, contact 21 engages successively contacts 23, 22 and 24, condenser 18 thus becoming charged, and then discharged through one or other of the relays 13 or 14 according to the direction of the relative rotation. The arrangement is such that one charge on the condenser is sufficient to operate only the first relay circuit connected, thus energizing the pitch-controlling mechanism in a direction which assists synchronization. Specification 634,413 is referred to.</p> |
