| 摘要 |
891,084. Incandecent electric lamps. PATENTTREUHAND-GESELLSCHAFT FUR ELEKTRISCHE GLUHLAMPEN. May 2, 1960 [June 24, 1959; Jan. 22, 1960], No. 15344/60. Class 39(2) An incandecent lamp has a coiled coil tungsten filament of length greater than the diameter of the neck of the lamp bulb, the filament being in one straight line at an angle with the lamp axis of between 20 degrees and 70 degrees and being positioned at about the centre of the bulbous portion of the lamp bulb. Preferably the angle is between 30 degrees and 60 degrees, and the nominal lamp rating is between 150 and 1000 watts and the voltage between 100 and 250 volts. Preferably, not more than two intermediate supports for the filament are used. The lamp may have two independently connected filaments arranged parallel to one another or at an angle of between 40 degrees and 140 degrees, preferably between 60 degrees and 120 degrees. Part of the bulb may be formed as a paraboloid of revolution and coated with a reflecting layer, one filament being at the focus of the paraboloid. In the form shown in Fig. 1, the filament 9 is mounted at 40 degrees to the lamp axis on leading-in wires 3 of nickel plated iron inside the bulb, copper clad wires 4 in the pinch 2 and copper wires 5 secured to the base shell 6 and eyelet 7. Two intermediate supports 10 of molybdenum are provided. Two filaments in parallel planes on opposite sides of the lamp axis may be provided for use together or separately, one being rated for 300 watts and having two intermediate supports and the other for 150 watts and having a single intermediate support. A disc 11 of mica, aluminium vapourized is provided to shield the seal and base from excessive heat. The bulb 29, Fig. 4, is designed as a paraboloid of revolution and coated with a reflecting layer 30 of silver or aluminium or of a suspended insulator of high reflectivity such as titanium dioxide or aluminium oxide. Two filaments 33, 34 are supported in a cross pinch 31 at right angles to one another and inclined at 45 degrees to the lamp axis. The centre S1 of filament 33 nearly coincides with the focus of the paraboloid while the centre S2 of the filament 34 is displaced a few millimeters from the focus in a direction away from the vertex of the paraboloid. The filament 33 provides a spotlight and the filament 34 is used for floodlighting. In a further modification, the two filaments are parallel to one another at an angle to the lamp axis, the centre of one filament lying at the focus of the paraboloid and the centre of the other being displaced from the focus in a direction along the axis. It is stated that, in lamps having a gas filling at a pressure exceeding atmospheric pressure, additives such as hydrogen or iodine may be included in addition to argon or krypton and nitrogen. |
