| 摘要 |
1,213,687. Radio-frequency suppressor devices. PATELHOLD PATENTVERWERTUNGS-UND ELEKTRO-HOLDING A.G. 21 Nov., 1968 [23 Nov., 1967], No. 55338/68. Heading H2H. [Also in Division H3] Radio-frequency heating apparatus comprises a high-frequency generator 1 operating between 1 and 20 MHz and linked to a capacitive load 15 through a wide-band filter which suppresses harmonics. The filter comprises a series element 3, in the form of a screened inductance 4, and a shunt element 7 consisting of two cylindrical electrodes 10, 11 arranged within a housing 8. The end surfaces 10a and 11a of the electrodes are electrically connected with the conducting line 9. In operation, the device operates as a low-pass filter between about 40 and 120 MHz, and above this the electrodes 10, 11 and the section of the conductor 9 between them behave as a pi-network. The lengths of the electrodes are chosen to provide quarterwave short circuits at two convenient frequencies. |
