GB913825A - - Google Patents

Abstract

913,825. Incandescent elements for electric lamps. PHILIPS ELECTRICAL INDUSTRIES Ltd. Oct. 10, 1961 [Oct. 13, 1960], No. 36341/61. Class 39 (2). An electric incandescent lamp has an incandescent element of refractory material having two spaced parallel limbs joined together at one end, the free ends being connected to current supply contacts, the length of the limbs being not less than four times the spacing between the limbs at their free ends. The refractory material may be a carbide, such as tantalum carbide, or a refractory metal. The limbs may be narrowed to about half width directly above the contacts to reduce shear stresses, and may also be thickened to compensate for the decrease in cross-section. Fig. 5 shows a limb 1 having cutaway portions 3 forming a narrow neck adjacent the contacts and thickened at the free end 6. Alternatively, when refractory metal strip is used, the edges of the ends of the limbs adjacent the contacts may be bent outwardly. In a further modification a series of parallel cuts may be made in the strip at the free end. Alternatively, the cuts may be made adjacent the free end and the metal 11, Fig. 12, twisted through a right angle.