GB1360080A - Magnetic system - Google Patents

Abstract

1360080 Magnetrons; magnets J A MELNIKOV 22 Dec 1971 59712/71 Headings H1D and H1P In a magnet system for creating an axially symmetric field along the axis of an annular magnet 14, Fig. 3, disposed within a magnetically soft, unsaturated screen 12, 13-e.g. for a magnetron 17 having a high frequency circuit 18- the annular magnet has one of its poles connected to the screen, and the other pole immediately adjacent the like pole of an axially magnetized bar magnet 15. The other pole of the bar magnet may, as shown, be connected to the opposite end of the screen, or may be spaced therefrom, either without (Fig. 1, not shown) or with (Fig. 5, not shown) a second annular magnet, to provide a second space in which a further electronic component, e.g. a second magnetron or a ferrite circulator, may be disposed. The annular magnet may be radially magnetized (Fig. 9, not shown). In further embodiments (Figs. 7 to 14, not shown) a screw-thread is provided on the inside of the screen and the outer periphery of the annular magnet or magnets, to permit adjustment of the field; and the bar magnet may be of other than circular cross-section, e.g. elliptical. The annular magnet may be of an iron-cobaltnickel-copper-aluminium-titanium alloy having up to 42% cobalt and up to 8% titanium, and the bar magnet of an iron-cobalt-nickel-copperaluminium alloy having up to 25% of cobalt. The relative dimensions of the magnets required to produce a low value of the variation of magnetic field with temperature is discussed.