GB780283A - Improvements in ionization chambers - Google Patents

Abstract

780,283. Ionization chambers. COMMISSARIAT A L'ENERGIE ATOMIQUE. June 22, 1955 [July 9, 1954], No. 18103/55. Class 39(1). The leakage resistance between the electrodes of an ionization chamber having one electrode arranged within the other is reduced by locating the voltage source inside the chamber and connecting one terminal to the inner electrode and the other to a conductor which passes through a wall of the chamber in insulated fashion and supports the voltage source. The chamber shown comprises a cylindrical envelope 1 of a synthetic resin, glass or other insulating material closed by end walls 7 and 8 and provided with an inner conductive coating 5 forming the outer electrode. Springs 6 fastened to the end wall 7 by screws 11 provide connections between the coating 5 and a metal member 10 screwed into a central opening in the wall 7. An insulating bush 3, preferably of polystyrene, is mounted in the member 10 and supports a screwed metal rod 17. A curved spring 20 is clamped between a nut 18, washer 19 and the bush 3 and makes contact with the insulated input member 21 of a pre-amplifier 22. The rod 17 extends beyond the bush 3 through a distance piece 23 and carries a battery 4. The negative terminal 24 of the battery 4 is connected to the rod 17 while the positive terminal 25 is connected through rods 26 and 27 to the apex 28 of a hollow second electrode 2 which surrounds the battery and extends as far as the negative terminal 24, but is spaced by an insulating ring 29.