| 摘要 |
904,284. Filaments for incandescent layers. THORN ELECTRICAL INDUSTRIES Ltd. June 16, 1961, No. 21911/61. Class 39 (2). An electric lamp especially for projection has a grid 21 of closely-spaced sections 23 formed from a single continuously wound filament, the end sections 24, 25 of the grid being straight, the ends of the filament 26, 27 being in line with the end sections and plugged by threaded plugs 29, 30, whereby squirming on heating of the filament coil is avoided. The threading may be produced by winding the core wire 30 with a finer wire 31 to form a thread. The lamp comprises a cylindrical envelope having a screwed cap and as internal glass press supporting wires 13, 14 which act as leading-in wires and also as supports for the filament. Upper and lower insulating bars are supported by brackets on the wires 13, 14 and carry sets of supporting hooks 19, 20 engaging in loops 22 formed by a single turn of the filament between each pair of adjacent filament sections 23. The grid may be of biplane form. In a modification, the end sections 24 and 25 of the grid are inclined away from the sections 23 but are maintained in alignment with the ends 26, 27. |
