GB636105A - Improvements relating to radio-receiving systems and radio-scanning and to switchingor modulating devices for controlling radio energy - Google Patents

Abstract

636,105. Wave-guides. SPERRY GYROSCOPE CO., Inc. April 24, 1945, No. 10339. Convention date, April 24, 1944. [Class 40 (viii)] A wave-guide switch comprises an apertured conducting cylinder mounted for rotation with its wall in the gap between adjacent sections of a waveguide. The invention is described with reference to radio-location apparatus involving a rotary scanning head comprising three parabolic reflectors such as 27, each having at its focus 30 the open end of a transmitting waveguide 29 and a receiving wave-guide 31. The three reflectors 27 together with their respective wave-guides 29, 31 and spaced extension guides 37, 7<1> are mounted on a housing 51 and turntable 15, which are rotated by a motor (not shown) driving a spindle 18, gearing 16, 17 and sleeve 24. Energy from a transmitter (not shown) is introduced by a wave-guide 14 into a fixed wave-guide 21 coupled to a rotatable extension 36 from which branch the extension guides 37. Interposed between adjacent ends of the transmitting guides 29 and receiving guides 31 and their respective extension guides 37, 71 is a stationary drum 45 of the form shown in Fig. 3. The two sections of the drum are formed with apertures 46, 49 having an angular extent corresponding to the field over which it is desired to radiate a beam. Thus, as each reflector in turn rotates into the field of desired radiation, its associated transmitting and receiving guides 79, 31 are connected through apertures 46, 49 to extensions 37, 71. Guide 71 communicates through co-axial line 72 and guide 78 to a receiver (not shown). Drum 45 is supported on a bush 54 having a bearing 53 to allow rotation of guide 36. Drum 45 is maintained stationary while the remaining parts rotate, by means of planet gearing 63, 64 carried by rotating guide 36 and engaging gearrings 61, 62 on fixed guide 21 and bush 54 respectively. The adjacent ends of the rotatable guides are provided with wave-trap couplings 67, 81. Similar coupling means are provided between fixed guide 21 and rotatable guide 36. Specifications 577,269, 600,502, [Group XL (c)], 608,839, and 636,155, [Group XL (c)], are referred to.