Abstract: For providing a lamp lighting device and a filament lamp wherein a wire breakage of the filament lamp can be detected without an excessive consumption of power while the device as a whole is not enlarged, a filament lamp is provided comprising a light emission tube having at least one sealing portion and in the interior of which at least one filament is arranged, internal leads connected to both ends of said filament, metal foils for power supply provided in said at least one sealing portion of the light emission tube and connected to said internal leads, and external leads connected to said metal foils for power supply; wherein a metal foil for detection is provided in said sealing portion and is connected to one of a said internal lead and a said metal foil for power supply, and an external detection lead is provided at said metal foil for detection.

Abstract: An incandescent lamp has an attachment for connection to a two-wire electrical power line and a bulb containing a radiating element. At least two filaments are housed in the bulb and constitute the radiating element, and circuitry has an input connected to the electrical power line and an output connected to filaments. When a selection signal indicating the desired brightness is passed to circuitry, preferably along the electrical power line, and acts in such a way that circuitry selectively provides a feed to filaments on the basis of the selection signal, a change in brightness is obtained without deterioration of the color characteristics because the filaments operate under their rated operating conditions. The change in brightness will not be continuous, but discrete, but is more than acceptable for domestic requirements even with a small number of filaments.

Abstract: A two-filament incandescent lamp and operating circuit well suited to lighting applications requiring high service reliability. In the lamp, the rated operating voltage of the second filament is greater than that of the first filament. In the operating circuit, there is an inductive reactance in series with the lamp and, in one aspect of the invention, an electrical connection across the lamp terminals for measuring the operating voltage of the lamp. After the power and rated wattage of both lamp filaments have been selected, matched values of inductive reactance and open circuit voltage of the operating circuit can be uniquely determined such that the following advantages are obtained. When the first lamp filament fails, the second filament comes into full brilliance. In a preferred embodiment of the invention, there will be no significant change in the luminous output of the lamp before and after failure of the first filament.

Abstract: An improved mounting structure for a three-way incandescent lamp is disclosed. The improved mounting structure has a three-pillar stem in which the conductive leads rigidly dispose a minor and major filament within the three-way incandescent lamp. The improved mounting structure has a conductive support member in common with both the minor and the major filaments which achieves improved mounting stability of the minor and major filaments relative to prior three-way incandescent lamps. Also disclosed is a method for the improved mounting structure which simplifies the manufacturing process of the three-way incandescent lamp. Further disclosed in one embodiment is an improved mounting structure which achieves simultaneous burnout of minor and major filaments of the three-way incandescent lamp.

Abstract: A tubular incandescent lamp for use in a fusing type lamp in a photocopy machine in which the lamp filament means is capable of operation at two different lengths on a selective basis as a function of the different lengths of paper that are to be reproduced by the copier. In one embodiment the filament means comprises a single linear filament with the contacts being taken at opposite ends of the filament for full length reproduction and along a predetermined length of the filament or shorter length of reproduction. In an alternate embodiment of the invention, two different length filaments are employed, each one selectively and mutually exclusively operated.

Abstract: The lamp shown herein is a beam mode fluorescent lamp for general lighting applications. The lamp comprises a light transmitting envelope, having a phosphor coating on its inner surface, enclosing a thermionic cathode for emitting electrons and an anode for accelerating the electrons and forming an electron beam, and a fill material, such as mercury, which emits ultraviolet radiation upon excitation. The cathode configuration provides for the elimination of "hot spots" due to ion bombardment at the low potential end of the cathode and for higher overall cathode emission of electrons. Various methods are employed to accomplish these ends, such as: segmenting the cathode, pitch variation of the cathode winding; ion probes and a non-uniform primary coil wound around a larger mandrel wire.

Abstract: The power/switcher module, bi-filament light bulb, and light bulb socket, of this invention are assembled with standard lamp industry hardware and fittings to provide a lamp fixture with conventional utility increased by the addition of an integrated automatic emergency lighting capability. Normal ON/OFF use of the lamp, while connected to household line current, also provides light bulb filament current for maintaining a full charge on a rechargeable storage battery. The loss of charging current through line current power failure, filament burn out, or selective disconnection by removal of the portable cord, immediately switches on the other filament to battery power, extending the emergency use to that of a portable lantern. Restoration of line current and/or a burned out filament automatically reverts the lamp to normal operation.

Abstract: A low pressure gas discharge lamp is provided with a pair of high power incandescent electrodes to increase output illumination at the lamp ends. In an alternate construction, the electrodes are of high power, low emissivity and are electrically connected to a second pair of high emissivity electrodes which provide the means for enabling the mercury discharge. With this second construction, the low emissivity electrodes can act as ballast for the circuit.

Abstract: A lamp is described having an internal switch for keeping at least one filament incandescent for a predetermined time after an external switch indicates the user wishes to turn the lamp off.

Abstract: A lighting system provided with a plurality of filaments, the wattage ratings of which differ in a predetermined relationship. The filaments are selectively energized so that the light intensity of the lamp may be varied in steps, without a change in color temperature which otherwise results when the intensity is varied in response to a varying voltage applied to a single filament.

Abstract: A motor vehicle rear lighting system comprises first and second lamp filaments in a single bulb envelope, the first lamp filament having a greater resistance than that of the second lamp filament. One or more electrical switches are operable, in one position, to connect the lamp filaments in series with a battery, and, in another position, to complete the circuit from the battery to the second lamp filament without the first lamp filament in series therewith. The arrangement is such that, in said one position of the one or more switches, the first lamp filament becomes luminous and, in said another position of the switch means, the second lamp filament becomes luminous. In one embodiment, a first lamp filament by-pass is provided and, in said another position of the electrical switch, the circuit to the second lamp filament is completed via the by-pass. In another embodiment, the electrical switches are arranged to connect the lamp filaments in parallel when the switches are in their said another position.