Abstract: A lamp control device in which the lamp circuit is controlled in accordance with a signal generated from a condition of an evacuated outer seal envelope. The signal being converted into a control action at the end of occurence of the signal so that the lamp heater contained in an inner envelope is rendered inoperable thereafter.

Abstract: An electronic ballast system includes a first capacitor (C.sub.2) electrically coupled to the first filament (30) of a gas discharge tube (12) and becomes the power supply of the gas discharge tube (12) subsequent to both its charging and discharging operations. The collector (38) of a transistor (Tr) is connected to the first capacitor (C.sub.2). The primary winding (22) is connected to the first capacitor (C.sub.2) and the collector (38) of the transistor (Tr) in parallel relation. The transformer (t) includes a secondry winding (24) which is connected on opposing ends thereof in feedback relation to the base (44) and emitter (42) of the transistor (Tr). Pulses of opposing current polarity (122 and 124) generated through the secondary winding (24) alternately provide conducting and non-conducting states for transistor (Tr) to discharge and charge the first capacitor (C.sub.2) through gas discharge tube (12) to provide a power source for operation of gas discharge tube (12).

Abstract: A spark arrestor for protecting a high intensity, gaseous discharge lamp, ballast and other circuit components against being damaged or destroyed by a large build up of voltage. The arrestor includes a multi-sided low dielectric disc with star-like conductive material on each side, the points of the star being opposite the mid-points of the sides. Terminals for connecting the spark arrestor across the secondary of the ballast, or other similar location, are connected to each of the star-like conductive materials. There is a non-conductive tubular shield around the disc to protect againt spreading of the spark, but the terminals extend from the ends of the shield for connection purposes.

Abstract: A thermal switch housing is provided in a recessed lighting fixture for interchangeably accommodating a thermal cut-off switch to protect against overtemperature conditions. The housing allows thermal switches having differing cut-off temperatures to be interchangeably removed and inserted to adjust for variations in fixture design, such as the size, shape and materials of construction.

Abstract: Method for heating and igniting as well as controlling or regulating the light flux of low-pressure gas-discharge lamps, including a ballast having an inverter for generating an ac voltage at inverter output terminals from a dc voltage generated from an ac supply network by rectifiers, the ac voltage having a frequency higher than line frequency, the ballast including an L-C circuit having a capacitor and a first choke connected between one of the inverter output terminals and a lamp, the lamp being in turn connected to another of the inverter output terminals, a second choke shunted across the lamp, the charge of the capacitor being constantly reversed by the inverter with controllable frequency, which comprises changing the inverter frequency in accordance with the desired light flux with constant ac voltage amplitude at the outputs of the inverter, tuning the frequency, voltage, capacitor, first choke and second choke to each other, circulating substantially the required heating current through heating coi

Abstract: The invention relates to a glow-discharge starter (10) having a bimetallic electrode (11) and a rare gas.According to the invention the glow-discharge starter also comprises a reversible getter (13) which, when the temperature increases, gives off a gas and, when the temperature decreases, absorbs the gas and the value of the gas pressure also determines the electric conductivity of the glow-discharge starter.A glow-discharge starter is thereby obtained in which undesired breakdown of the glow-discharge starter can be prevented by controlling the gettering temperature.

Abstract: A high intensity discharge lamp includes, within the outer envelope, a strip of niobium foil serially connected between a power source and one of the electrodes of the arc tube of the lamp. The foil is not a power consuming element but will oxidize and open the circuit, thus extinguishing the lamp, in the event the outer envelope is ruptured.

Abstract: An arc extinguishing means for a high intensity discharge lamp comprises a meltable fuse wire a portion of which is surrounded by a refractory hollow sleeve of larger diameter than the fuse wire. The remaining volume of the sleeve is substantially filled with a pyrophoric material which, at an operating temperature available within the lamp, will spontaneously ignite in the presence of oxygen and generate sufficient heat to melt the fuse wire and thus open the circuit, extinguishing the lamp.

Abstract: A liquid level presence detection circuit includes a selectively gatable TRIAC serially connected with a load and triggered into conduction by twin sensitive-gate SCR's connected anode-to-cathode with the gates of the SCR's connected to voltage divider circuits which provide gating current to the SCR's in response to the presence of a conductive liquid bridging the two spaced apart contacts of a liquid presence detecting probe. The circuit is used in wet-niche type lamp assemblies that provide underwater illumination in swimming pools and the like and in which cooling is effected by the surrounding liquid. The detection circuit advantageously interrupts the flow of electrical energy to the lamp when the level of surrounding liquid falls below a predetermined level to prevent over-temperature operation of the lamp and consequent damage thereto and resumes the flow of electrical energy to the lamp when the level of the surrounding liquid increases to a safe level to permit adequate cooling thereof.

Abstract: A domestic appliance comprises a programming device receiving on-time information and for updating, by way of repetitious signals, the on-time yet to be completed. The repetitious signals continuously activate an activation signal which is independently terminated if the repetitious signals do not appear. When the activation signal is present, first and second switching components are activated so that a discharge tube can emit ultraviolet radiation. A detection element detects whether the first and second switching components are deactivated outside the on-time. If one of the two switching components remains active outside the on-time, the detection element supplies a signal to inhibit the next start signal.

Abstract: A compact electronic assembly operable to control the energization of an electrical appliance is adapted for convenient mounting in an existing, standard electrical wall-switch box. A disconnectable electronic control means is mounted on the outside of the switch face plate and communicates with circuitry inside the wall-switch box by means of a plug-in connection through the aperture of the switch face plate. According to one aspect of the invention, a programmable electronic timer-switcher comprises a mounting plate which is secured to the opening of the wall switch box. A multiple-conductor receptacle is secured to the mounting plate, which also preferably serves as a heat sink for a switching means such as a triac. The receptacle is aligned behind the rectangular aperture of a standard switch face plate to permit plug-in connection to a programmable electronic timer disposed exteriorly of the face plate.

Abstract: An underwater light circuit employs electrodes exposed to water, a light, and circuitry connected with the electrodes and light filament to control current flow to the filament.

Abstract: A mechanical safety switch for high intensity discharge lamps designed to open and remove the current from the arc tube to extinguish the discharge when the lamp envelope is broken in which a leaf spring switch arrangement is used comprising two leaf spring members which are in contact along a substantial portion of their lengths to thereby reduce the current carrying requirement per unit area of the leaf springs.

Abstract: A wet-niche type lamp for providing underwater illumination in a swimming pool or the like includes an over-temperature protection circuit which interrupts the supply of electrical energy to the lamp when the level of the cooling water surrounding the lamp drops below a predetermined level. The circuit includes thermistor mounted in an heat exchange relationship with the surrounding water so that heat energy generated in the thermistor, as a consequence of the current flow through it, is normally transferred to the surrounding water. Should the level of the surrounding water drop below that of the thermistor, the thermistor heat energy quickly evaporates any remaining water film on the exterior surface of the thermistor to allow its temperature to rise. The control circuit, in response to the temperature increase, interrupts the flow of electrical energy to the lamp to prevent over-temperature operation.

Abstract: A high intensity discharge lamp having an inner tube in which a discharge takes place to produce visible light and ultraviolet radiation and an outer envelope which blocks harmful ultraviolet radiation. An oxidizable element of a refractory metal is provided in the voltage supply to the arc tube internally of the outer envelope which element oxidizes when the outer envelope is broken and burns through to remove the voltage from the arc tube and to extinguish the arc.

Abstract: A cycling cut-off arrangement and method of protecting from burn-out a ballast-starter of a luminaire having a power source normally connected to the ballast-starter, and a high pressure sodium lamp across which the ballast-starter supplies voltage of predetermined magnitude to operate the lamp, in the event of a cycling malfunction wherein the lamp is extinguished and the ballast-starter applies a voltage of greater magnitude than the predetermined magnitude across the extinguished lamp. The voltage across the lamp is detected, and a current signal is generated when the voltage magnitude across the lamp reaches a threshold magnitude which is greater than said predetermined magnitude. In response to the generation of the current signal, the power source is disabled from the ballast-starter to protect the latter from damage.

Abstract: A circuit for protecting a ballast in a high pressure metal vapor, such as sodium, lamp system which includes means for interrupting the power supply to the ballast in the event that no current is flowing through the lamp, once the system has been energized. The circuit has automatic compensation for short interruptions and for the time which it normally requires for the lamp to ignite. The absence of current flow through the lamp is sensed and this information used to provide the protection.

Abstract: The invention relates to a sun lamp provided with a timer circuit that includes a capacitor. As soon as the capacitor reaches a certain charge condition the sun lamp is switched-off.The sun lamp also comprises a safety circuit responsive to a given level of current through the capacitor, which indicates a defect in the timer circuit 2, to rapidly terminate the irradiation.

Abstract: A high intensity discharge lamp having an inner tube in which a discharge takes place to produce visible light and ultraviolet radiation and an outer envelope which blocks harmful ultraviolet radiation. An element is provided to extinguish the discharge when the outer envelope is broken.

Abstract: Simplicity is the height of invention.In order to conserve energy when the thermostat turns air conditioning apparatus on, in the present invention apparatus is employed to automatically reduce energy input to, and also heat output from, illuminating apparatus in the area being air conditioned. This is feasible because, in many instances, increased illumination from the sun, during daylight hours, renders the need much less for illumination from lamps or artificial luminares. In other instances, turning off a few lamps in each office can avoid blackouts, brownouts, overloading of generators, and burning out of air conditioning apparatus and other electrical appliances.

Abstract: The inner arc tube of some jacketed discharge lamps transmits ultraviolet radiation which is normally intercepted by the glass outer envelope. To prevent harmful release of such radiation in the event the outer envelope should be shattered, a mechanical disconnect is provided in the interenvelope space comprising separable conductors which are part of the arc tube supporting frame and which are maintained in engagement by the outer envelope. Upon fracture of the outer envelope, spring pressure forces the conductors apart whereupon the circuit is opened and the arc tube is disabled.

Abstract: HID lamp has resilient safety switch positioned proximate the inner surface of the dome portion of the protective outer envelope in contact with an extremity of a resilient leaf-spring support portion of the arc tube frame, to maintain the switch in a closed position. When the envelope is shattered, the normally closed switch will open to break the electrical path to the arc tube, thereby rendering the lamp inoperative.

Abstract: A ballast for a rapid start fluorescent lamp with heated filaments has a secondary winding supplying lamp current, tertiary windings for supplying heater current to the filaments, and solid state switching circuits in secondary circuits through the filaments. Each switching circuit, which may be integrated with the ballast circuit or connected to a filament within the lamp envelope, comprises two voltage divider resistors having a common junction coupled to the gate of a triac whose primary electrodes are connected in parallel with the voltage divider. The triac is in series with the filament and supplies heating current to the filaments prior to lamp starting. When the lamp starts and conducts rated operating current the voltage divider reduces the voltage at its junction and at the triac gate below triac breakdown level thereby substantially eliminating heater current.

Abstract: A rapid start fluorescent lamp ballast with a secondary winding supplying lamp current and tertiary windings for supplying heater current, has a magnetic switch which senses current through the secondary winding and opens the heater current circuit after the lamp starts and draws operating current from the secondary winding. The current sensing magnetic switches shown are a slow acting relay with its coil in the secondary circuit and a magnetic reed switch physically disposed in the magnetic field of the secondary ballast winding.

Abstract: A filament coil is connected in series with an arc tube to form a self ballasted lamp. An internal starting coil is connected across the arc tube through a bimetal switch, which is normally closed, for energizing the starting coil. When an arc is struck and the tube temperature rises, the bimetal switch opens to cut out the starting coil. A fuse wire is connected across the bimetal switch to facilitate flashing of the filament coil by application of less than rated voltage during evacuation of the lamp envelope when the bimetal switch is normally open because of the elevated temperatures required for glass working and sealing. Upon subsequent application of rated voltage, the fuse wire melts and the lamp operates in its normal manner.

Abstract: A color television receiver circuit for preventing excessive X-radiation is described. A spark gap is coupled between the high voltage supply for the color tube and ground. Should the high voltage output tend to exceed a level beyond which undesirable X-radiation may be emitted, the spark gap breaks down, effectively shorting the high voltage output to ground and preventing the excessive voltage condition. At the same time, the picture is eliminated and the viewer must have the set serviced. Two embodiments are described in detail. In one, the spark gap is built into the tube socket of a high voltage rectifier; in the other, the spark gap is incorporated into a voltage multiplier circuit.

Abstract: A lighting system for gaseous-discharge lamps for applying high voltage pulses to ignite the lamp and for discontinuing the application of high voltage pulses when the lamp is operating. The system includes ballast facilities having an inductive portion, and a control circuit which is responsive to a voltage induced in the inductive portion when the gaseous-discharge lamp operates. When the control circuit is operative, the pulsing portion of the system is disabled. The system is arranged so that the components of the control and pulsing circuits are not subjected to the application of high voltage pulses at any time.