GB580057A - Piezo electric crystal cabinet - Google Patents

Abstract

580,057. Constant - temperature containers. STANDARD TELEPHONES & CABLES, Ltd. March 31, 1944, No. 6007. Convention date, April 1, 1943. [Class 64 (ii) ] [Also in Group XL] A container maintaining piezo-electric crystals at constant temperature comprises a base 11 carrying crystal supports 25 enclosed in an inner housing 41 having an outer housing 14 spaced therefrom, the base and housings being of heat-insulating material, e.g., synthetic resin. An electric resistance heater 38 is wound on an aluminium casing 36 supporting a thermostat 39 and spaced between the inner and outer housings. The base 11 carries hollow contact pins P, a positioning stud 12 and lugs 16 engaging inner walls of the rectangular outer housing. Screws 18 pass through the base 11 into inwardly enlarged corners of the housing 14. The crystals 27 are held by spring clips 25 with contact springs 26 carrying metal plate surface contacts engaging opposite sides of the crystals, which are held against insulating posts 28, all mounted on an inner base 20 of heat-insulating material. A rectangular positioning bar 24 fits into registering slots in contiguous faces of the inner base 20 and a pedestal 21 which spaces the inner and outer bases to form a channel for the leads 30 passing to pins P. The metal housing 36 is secured to the inner base and supports the bimetallic thermostat 39. One end of the heating wire 38 passes to a thermostat terminal 40, the thermostat terminals and. other end of the heating wire being connected to pins P. A condenser may be mounted across the thermostat.