A magnetron device for the measurement of low pressures

摘要

914,324. Ionization gauges. NATIONAL RESEARCH COUNCIL. Aug. 29, 1961 [Aug. 29, 1960], No. 31140/61. Addition to 890,920. Class 39 (1). A magnetron diode for measuring low pressures comprises two concentric cylindrical electrodes, the cathode having a pair of transverse end flanges 12, 13, Fig. 1, which present smooth polished and rounded surfaces to the anode to suppress field emission therefrom. The cathode surfaces may be electropolished, and the cathode has a #-ray emitter applied to some point on its surface preferably on the main body part, but possibly on one of the end flanges. The cathode 11 surrounds the anode 10, or vice versa, Fig. 2 (not shown). In Fig. 2 the envelope end caps are sealed to the anode. The anode is apertured in Fig. 2 to allow connection of the magnetron diode to the device of which the pressure is to be measured. The magnet is cylindrical or U-shaped.