| 摘要 |
1,075,317. Thyristor switching circuits. DANFOSS A.S. May 13, 1965 [May 22, 1964], No. 20249/65. Heading H3T. [Also in Divisions Cl and G4] An A.C. switching circuit comprises an element 11 rendered conductive by ultra-violet radiation, temperature or pressure and fed from an A.C. source U-O by a voltage multiplier 7, 8. When the voltage across A-O is sufficient, element 11 conducts to discharge capacitor 8 through the element 11 and fire a device 9 which remains conducting until the voltage across it falls to a predetermined level. The current through device 9 energizes relay 4. In a modification, Fig. 2 (not shown), the cathode of device 9 is connected to the anode of the rectifier 7 and the relay 4 and capacitor 5 are connected in parallel in one of the leads 3, thereby reducing the number of conductors in cable 6 to two. The switching circuit may be used in a burner control system. |
