Electrostatic relay for measuring small currents and charges

964,173. Electrostatic switches. COMMISSARIAT A L'ENERGIE ATOMIQUE. Dec. 13, 1960 [Dec. 23, 1959], No. 42846/60. Heading H2B. An electrostatic relay comprises a movable electrode of ferromagnetic material biased away from a fixed electrode by a magnet. Fixed electrodes 18, 19 are mounted in adjustable glass members 27, and the movable electrode 3 is secured to a rod 16. A permanent magnet 21 having a polepiece 20 adjacent the free end of movable electrode 3 is screwed into an adjustable support 22. The electrodes 18, 19 are held by a support 23 integral with a brass tube 24 fixed to a glass support 17. The relay is enclosed in a glass tube 25 which is either evacuated or filled with a reducing or inert gas. The tube 25 is reinforced by a metal ring 26. In an alternative embodiment, the movable electrode is secured to one polepiece of a magnet and extends towards the other. The magnet has a variable magnetic shunt so that the biasing force on the electrode may be varied. It is stated that the relay may be used to measure charge, current or resistance.