GB1081908A - Improvements in or relating to contact connections for wire-shaped heating elements - Google Patents

Abstract

1,081,908. Uniting ceramics to metal; soldering. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. Feb. 24, 1965 [Feb. 27, 1964], No. 7968/65. Headings B3R and B3V [Also in Division H2] A contact connection between a pin 7 and an element 2 insulated by a powdered metal oxide 3 from its metallic envelope 1 comprises a ceramic insulating sleeve 6 secured by solder, and a soldered joint 14 between the element 2 and the pin 7. The insulator 6 may be connected direct to the envelope 1 by soldering with a eutectic of Ag and Cu containing Ti, or the insulator could be metallized locally for use with a Cu-Ag solder. Preferably an intermediate metal sleeve 5 of Fe-Ni is used which is connected at 11 to the envelope by a Cu-Ag solder, the insulators 6 being connected to the sleeve 5 and the Fe-Ni pin 7 at 12, 13 by the Ti solders. The insulator 6 may be of a lighttransmitting sintered aluminium oxide. After degreasing, the parts are assembled with the rings 11-14 of solder and a further ring 8 of aluminium oxide, and the assembly heated to about 1000‹ C. in a hydrogen atmosphere. The solder 14 consists of 85% Ag and 15% Mn. A connection between two conductors (36, 37, Fig. 2), and pins (26, 28) is made in two soldering stages. First, the intermediate Fe-Ni sleeve (23) is positioned and the ring (38) of Cu-Ag solder, followed by the ceramic rings (24, 31), Ni couplings (25, 27), a ceramic spacer (32), rings (40, 41) of Ag-Mn solder and the Fe-Ni pins (26, 28). The first soldering operation now follows, the assembly remaining in the hydrogen atmosphere until cool. The ceramic insulator (29) and rings (43, 44, 45) of the Ti solder are now positioned for the second soldering stage.