GB859019A - Improvements relating to screening arrangements for electronic devices - Google Patents

Abstract

859,019. Discharge apparatus. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. April 27, 1959 [March 28, 1958], No. 10114/58. Class 39(1). [Also in Group XXXVI] In a screening assembly for an electronic device, e.g. a thermionic valve, a screening can 1, Fig. 1, is formed with at least two external lugs 4, and a sheet metal saddle member, adapted for permanent attachment to a chassis or the like, includes an annular ring having an internal lip of inverted U-shaped cross-section having slots 9 through which the lugs 4 can pass and recesses 8 which the lugs engage after rotation of the can. As shown there are two alternative positions for the can which is urged upwards by a spring 2 in the top of the can or an annular spring at the top of the valve socket. The saddle member may be bolted to an apertured chassis, to the other side of which is secured the valve socket. Alternatively, the socket 14, Fig. 4, is formed with a flange 13 having slots 16 through which pass lugs 15 of the saddle, Fig. 3, and recesses 18 which are engaged by upwardly-bent lugs 17, after rotation of the saddle. In a further arrangement a flange is formed mid-way along the screening can and has external lugs which engage a saddle mounted on an auxiliary chassis, the can and valve extending through this chassis to a valve socket carried on a main chassis which is spaced from and parallel to the auxiliary chassis.