Abstract: An arc discharge current occurred in dc-illuminated incandescent lamp can be effectively suppressed with an apparatus comprising first resistance connected in series with an incandescent lamp circuit; the second resistance connected in series with the incandescent lamp circuit; and a reverse-blocking triode thyristor connected in parallel with the second resistance and openable with the voltage drop produced between the first resistance by an arc discharge current.

Abstract: A high-pressure metal vapor discharge lamp comprising an outer tube, a light emitting tube located within the outer tube and made of a light-transmissive ceramics material, and a fuse electrically connected in series with the light emitting tube, in which said fuse has such a blowing characteristic as given by the following equation and at a rated output during the lighting of the lamp the density of a current through the fuse is not more than 23.9 A/mm.sup.2 :log T.sub.1 <AlogI+BA=-1.02.times.10.sup.-2 (D.sup.2 t)-0.885B=2.64.times.10.sup.-2 (D.sup.2 t)+1.01T: required blowing time (seconds) of the fuseI: blowing current (A) of the fuseD: inner diameter (mm) of the light emitting tubet: wall thickness (mm) of the light emitting tube.

Abstract: A discharge lamp is provided with a starting aid in the form of a loop of conductive wire arranged around the discharge lamp arc tube and a novel spark gap. A conductive element is electrically connected between the loop and an insulating sleeve adapted to form a spark gap by means of the conductive element wrapped around an opening in the insulating sleeve. The opening can be in the form of a drilled hole or slot and the arrangement is particularly useful in the restricted confines of a sealed beam reflector lamp.

Abstract: The enclosed electronic flash device for a camera includes a booster circuit connectible to an electrical power source or battery, a high voltage rectifier diode for rectifying the output of the booster circuit, and a storage capacitor. A main power supply switch and an auxiliary power supply switch are connected in series between the negative poles of the power source and capacitor. The auxiliary power supply switch is arranged to close when the flash device is attached to the camera. A signal terminal is connected to the negative pole of the storage capacitor through other circuit elements and another signal terminal is connected to one contact of the auxiliary power supply switch, which is connected in turn to the negative pole of the storage capacitor. The auxiliary power supply switch is connected in series with the main power supply switch at a point farther from the negative terminal of the battery than the main power supply switch.

Abstract: A metal vapor discharge lamp has a burner for sealing xenon gas, mercury and a light-emitting additive in a translucent ceramic tube, a starting device of a thermal switch type which has a series circuit of a thermal switch and a coil filament and which is connected in parallel with the burner, and an outer envelope for sealing the burner and the starting device therein. In the lamp, the following inequalities must be satisfied:13.3.ltoreq.P.multidot.(B/A).ltoreq.6650.05.ltoreq.d.ltoreq.0.122,200.ltoreq.T.ltoreq.2,800where A is the volume (cm.sup.3) of the outer envelope, B is the volume (cm.sup.3) of the burner, P is a gas pressure (Pa) at room temperature of xenon sealed in the burner, d is a diameter (mm) of the coil filament, and T is a temperature (K) of the coil filament during operation.

Abstract: A rapid-start fluorescent lamp includes a circuit breaker therein having a sealed glass bottle, a thermally sensitive bimetal switch within the glass bottle, a pair of electrical conductors sealed into and passing through the sealed bottle with one electrical conductor attached to the bimetal and the other electrical conductor contacting the bimetal with each of the pair of electrical conductors formed of Dumet wire plated with an electrically conductive metal whereby formation of insulative oxides on the electrical conductors is inhibited.

Abstract: A rapid-start fluorescent lamp includes a circuit breaker having a sealed glass bottle, a pair of electrical conductors sealed therein and passing therethrough and a thermally sensitive bimetal switch within the glass bottle with the bimetal switch having a pair of leg portions of unequal length.

Abstract: High-pressure discharge lamps generating UV radiation are provided with an internal safety switch, that interrupts the current circuit through the lamp upon fracture of the outer lamp envelope. In lamps according to the invention the safety switch is a member of a material selected from the group consisting of zirconium-aluminum alloys, sintered zirconium powder and sintered mixtures of zirconium powder and nickel powder.

Abstract: A high intensity discharge lamp with a safety switch which automatically shuts off the lamp upon rupture of the outer envelope. The switch is formed by a carbon rod disposed in the interior space between the arc tube and the outer envelope and connected in series with one of the electrodes so that the current flow through the rod maintains it at an elevated temperature during operation of the lamp. Upon rupture of the outer envelope, the carbon rod oxidizes and falls, thereby interrupting the electrical path to the electrodes.

Abstract: The invention is directed to a method of preventing cathode damage when switching on an electron gun having a field emission cathode assembly including a cathode, a first electrode and a ground electrode. During normal operation of the electron gun, an extraction voltage is applied across the cathode and the first electrode and an accelerating voltage is applied across the cathode and the ground electrode. A direct galvanic connection is established between the cathode and the first electrode prior to normal operation of the electron gun. During a burn-in period, only the accelerating voltage is applied. This accelerating voltage may include an overvoltage of up to twenty percent. Then the galvanic connection between the cathode and the first electrode is interrupted and the extraction voltage is applied. An arrangement for carrying out the invention is also disclosed.

Abstract: A rapid-start fluorescent lamp includes a circuit breaker having a pair of electrical conductors sealed into a bulb and connecting a lamp lead to the electrode of the lamp. The circuit breaker includes first and second electrical conductors and a bi-metal strip having a first end portion connected to a first conductor and a second end portion connected to a second conductor at ambient bulb temperature, disconnected therefrom at a higher given range of temperatures, and the portion of the bi-metal strip intermediate the end portions connected to the second electrical conductor at temperatures higher than the given range of temperature.

Abstract: A rapid-start fluorescent lamp includes a pair of spaced electrodes within an envelope with one electrical lead connected to an electrode and the other lead coupled to the electrode by a thermally-sensitive bi-metal strip whereby one end of the bi-metal and one end of a conductor are formed to provide a straight member within a U-shaped member such that the straight U-shaped members are in electrical contact at temperatures above and below a given range of temperatures and electrically disconnected at the given range of temperatures.

Abstract: A rapid-start fluorescent lamp has a thermally-sensitive circuit breaker disposed thereon for disconnecting the electrodes of the lamp from an energizing source at a given range of bulb temperatures and for connecting the electrode to the energizing source at bulb temperatures above and below the given range of bulb temperatures whereby the electrodes are energized during lamp manufacture and until conductivity of the lamp is established.

Abstract: A high pressure sodium vapor lamp having a time fuse device effective for predeterminedly establishing the anticipated life of the high pressure lamp is disclosed. Also disclosed are various embodiments of the time fuse device.

Abstract: A rapid-start fluorescent lamp includes a pair of spaced electrodes within an envelope having a fill gas and a phosphor-covered inner wall surface with a circuit breaker having a glass bulb with a wall thickness in the range of about 0.016 to 0.018 inch positioned within the fluorescent lamp.

Abstract: In a high pressure discharge lamp device provided with an inductive stabilizer and a starting circuit consisting of a serial circuit of a resistor and a bimetal switch, a pulse waveform conversion circuit is arranged therein to reduce the pulse peak of the starting voltage and also broaden the pulse width of the starting voltage. The pulse waveform conversion circuit comprises a serial circuit of a resistor and a switching element, such as micro-gap element, which operates at a voltage lower than the starting voltage of the discharge lamp but higher than the secondary load-free voltage of the stabilizer.

Abstract: A protection system for protecting the secondary windings of current transformers against overvoltages. The protection system consists of a device shunting the secondary winding and having a triggering device operative when the winding is subjected to a voltage higher than the voltage appearing across the terminals of the secondary winding, under normal operating conditions and during a fault on the HV power network. The shunting device comprises a latching relay incorporating a coil which is energized by the triggering device to short-circuit the current secondary transformer through the relay contact, and, also, a voltage regulator connected in parallel with the relay coil. This protection system is simple, compact, lightweight and consumes no energy when the current transformer operates under normal conditions.

Abstract: A ballast for a sequence start series operating circuit that includes two rapid start gaseous discharge lamps. The circuit includes a transformer with a primary winding and a loosely coupled secondary winding, a series first capacitor for providing a leading current when both lamps have been ignited and are operating and a second capacitor shunting the second-to-ignite lamp to by-pass that lamp during ignition of the first-to-ignite lamp and thereafter to develop a voltage across the second capacitor sufficient to ignite the second-to-ignite lamp when current flows in the by-pass branch. The lamps are of a variety which produces an undesirable current peak in the second-to-ignite lamp on each half cycle because the shunting second capacitor dumps its charge accumulated during each half cycle into the lamp.

Abstract: A rapid start fluorescent lamp comprising a pair of cathode mounts each having a pair of lead-in wires for cathode heating current, and a thermal switch to turn off the heating current after sufficient cathode heating for the lamp to operate. A third lead-in wire in each mount bypasses the thermal switch and is used for heating the cathodes to activate them during manufacturing.

Abstract: A rapid start fluorescent lamp having a glass envelope with a phosphor coated inner surface, a low pressure gas fill and an electrode at each end includes at least one electrode disconnected switch having a bimetal switch normally closed at room temperature and open at a predetermined temperature higher than room temperature with the bimetal switch connected to the electrode and to an electrical lead extending from the lamp to an energization source.

Abstract: An energy-saving instant-start series-sequence fluorescent lamp system includes power-reducing capacitor means connected in series circuit arrangement with one or both lamps in a two-lamp system. A protective device is connected in circuit with a first lamp of the system so that in the event the second lamp fails to operate and causes a high current to flow through the first lamp, the protective device reacts to prevent the system from being damaged. A lamp incorporating the power-reducing capacitor and protective device is also disclosed.

Abstract: An electric lamp construction is described having at least one pair of conductive inlead wires of dispersion strengthened copper alloy to serve as the sole means of the physical support for a resistive incandescent filament physically connected thereto, and wherein one of said inlead wires is further electrically connected to a fuse lead of a copper solution alloy with nickel and tin. Said fuse metal produces less metal arc damage when melted during the lamp operation as compared with other fuse metals now in commercial use.

Abstract: In a metal vapor discharge lamp for operating it by high voltage generated in the actuation of a heat sensitive switch means in an outer bulb, a relatively low pressure of a sealed gas or mercury is sealed in the outer bulb to operate the heat sensitive switch means in the gas atmosphere to control the surge voltage to a desired degree whereby the discharge lamp is operated without failure and the insulation breakdown of a ballast and an operation circuit is prevented.

Abstract: An incandescent lamp possessing a ballast circuit comprising a resistor and capacitor in parallel further includes means for interrupting the connection between the ballast and external contacts provided on the base of the lamp. This interruption occurs upon removal of the lamp from its matching socket to prevent the occurrence of capacitor voltage across the external lamp contacts. The circuit is again closed upon reinsertion of the lamp in the matching socket to permit normal lamp operation.

Abstract: High-intensity-discharge (HID) sodium lamp has a starting aid comprising a conducting ceramic which is hermetically sealed to and extends through an alumina arc tube at least at one end thereof to form an electrically conducting path. The conducting ceramic is fused to the alumina arc tube and is electrically conductive by virtue of having embedded therein a small percentage of finely divided refractory metal. At least during starting, the conducting ceramic is electrically connected through a resistor to the opposite lamp electrode and, as a result, on application of energizing potential, a glow discharge is established between an arc-tube-interior portion of the conducting ceramic and the adjacent electrode to ionize the atmosphere within the arc tube and facilitate lamp starting.

Abstract: In an incandescent lamp having a glass envelope joined to a base member and a filament mounted within the envelope, an improved fuse wire comprises a portion of one or both of the lead-in wires connecting the filament to the base member. The fuse wire is made of an Aluchrom alloy containing Chromium, Nickel and Iron, or is made of a Cronifer alloy containing Chromium, Iron and Aluminum. The Aluchrom or Cronifer fuse wire, upon lamp failure and fuse burnout, exhibits reduced arcing melt-through of the lamp base compared with lamps having prior art fuse wires, for improved safety thereof.Further the Aluchrom or Chronifer fuse wires have an I.sup.2 t energy rating which permits the use of larger diameter fuse wires which can more readily be processed by lamp production machinery than the smaller diameter lamp fuse wires of prior art materials.

Abstract: An improved fuse means for use within an electric incandescent lamp (e.g., tungsten halogen). The fuse is located within a ceramic base to which the press-sealed end of the envelope is affixed (e.g., cemented). The improved fuse means comprises a first conductive (e.g., nickel) wire segment of rectangular cross-sectional configuration and a second conductive (e.g., nickel) sleeve member crimped about an end portion of the first wire segment and including a flat region which in turn is fixedly secured (e.g., welded) to one of the lead-in wires projecting from the lamp's press-sealed end portion. In an alternative embodiment, a second sleeve member and conductive wire segment is utilized.

Abstract: An enclosed electrical device (42) includes an electrical circuit (50) having elements (48-68) which lie substantially in and along a plane (115). A member (70) is applied to a one side and a member (85) is applied to another side of the circuit (50) for at least partially enclosing the same. Conductors (48) and (49) of circuit (50) are fixedly penetrated, preferably by pins (74) which are fixedly engaged to enclosure members (70) and (85). Such engagement is advantageously provided by making the pins (74) an integral part of member (70), for example by including pins (74) in a premolded member (70). Such engagement is also advantageously provided by making pin-engaging sockets (94) an integral part of member (85), also for example by including the sockets (94) in a premolded member (85). By a preferred friction fit of pins (74) and sockets (94), the enclosure members (70) and (85 ) and circuit elements (48-68) are sufficiently fixed relative to one another to resist forces applied thereto in service.

Abstract: A high intensity discharge lamp includes arc extinguishing means functional when the outer envelope of the lamp fails. The extinguishing means comprises a pressure sensing diaphragm and a terminal which will melt back when an arc is drawn therebetween. The extinguishing means operates within a time interval of several milli-seconds.

Abstract: A high intensity discharge device includes a reactive element which will oxidize and grow dimensionally to open the lamp circuitry in the event oxygen leaks into the outer envelope of the lamp.

Abstract: A three-terminal thermal switch having a common connector arm biased against a terminal of fusible material. When the terminal is softened or melted by current, the connector arm is released and moves into contact against a second terminal. Positioned in the base of a long-life dual-filament incandescent light bulb, the switch causes one filament to be energized until it burns out, and then connects the other filament to be energized.

Abstract: A light source, including a high pressure discharge lamp and a starting pulse generator, such as a spiral line pulse generator, utilizes a generally straight elongated conductor, or starting aid, in close proximity to an outer surface of the discharge tube to provide efficient coupling of the starting pulse to the discharge lamp. The starting aid extends between a region proximate one of the electrodes and a region proximate the other of the electrodes. The starting aid provides within the discharge lamp an ionization path of minimum length free of circumferential turns when the conductor is energized by the pulse generator. The starting aid can be affixed to the discharge tube or can be mounted in one or more support brackets.

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: A fluorescent lampholder fitting has a fluorescent lamp having first and second ends respectively provided with starting filaments. The lamp is supported by a housing which also encloses a solid-state fluorescent ballast and which also incorporates a male screw base electrical connector for supporting the housing in a portable lamp or lighting fixture. The male screw base is provided with three electrical input connections so configured to be electrically connected and selectively switched when installed in a three-way lampholder of the portable lamp or lighting fixture. The lampholder fitting is provided with a center-tapped step-down transformer which has three terminals attached to the three respective connections of the three-way male screw base. The step-down transformer has a single low-voltage secondary winding which connects to the input terminals of a full-wave bridge rectifier which has its rectified output connected to a high frequency oscillator.

Abstract: A jacketed discharge lamp which would release ultraviolet radiation in the event of fracture of the outer envelope is provided with a disabling fuse link which oxidizes in the event of breakage. The link consists of an alkaline earth metal film, suitably a barium film which may be deposited on a ceramic substrate for connection into the circuit. The outer envelope is evacuated or may contain an inert gas.

Abstract: A glow bottle starter having three lead-in wires and containing two bimetals connected together at one end and a rigid tungsten rod. The bimetals make normally closed contact with the tungsten rod in the quiescent state of the starter, and upon electrical current flow through one or both of the bimetals to cause elevation to a predetermined temperature, the bimetals are operative to separate from the tungsten rod. In a circuit including the glow-bottle starter for starting a discharge lamp, one of the bimetals and the rigid tungsten rod are connected across the output of a ballast circuit, and the tungsten rod and other bimetal are connected across the lamp.

Abstract: The invention relates to a discharge lamp which has a discharge vessel provided with an external auxiliary electrode. The lamp also has a bimetal which in the inoperative condition of the lamp causes the external auxiliary electrode to bear against the discharge vessel. According to the invention the auxiliary electrode is connected to an end of only one bimetallic strip and in the operating condition of the lamp the auxiliary electrode is remote for the greater part from the discharge vessel due to the action of the bimetal. Combined with an operating condition of the lamp in which no hindrance is experienced from the auxiliary electrode.

Abstract: A high pressure sodium lamp, which includes a discharge tube enclosing xenon at pressures in excess of 300 torr, is reliably started by the combination of an igniter, a conductor wrapped around the discharge tube, and a switching circuit. The igniter provides periodic pulses of 2500 to 4000 volts with a duration of at least one microsecond. The switching circuit provides a high voltage pulse having an amplitude about equal to the amplitude of the periodic pulses and a duration much greater than the duration of the periodic pulses. The conductor intensifies the electric field within the discharge tube. A conventional lamp ballast provides ac power during starting and normal operation.

Abstract: Method and apparatus for starting high intensity discharge lamps utilizing a spiral line pulse generator to generate high voltage, short duration starting pulses. The spiral line pulse generator includes two conductors and two insulators, each in the form of an elongated sheet, in an alternating arrangement which is rolled together in a spiral configuration having a plurality of turns. A high voltage, short duration pulse is provided upon closure of a low inductance switch coupled between the conductors. The pulse is coupled to the discharge lamp by an elongated conductor located in close proximity to the discharge tube. The spiral line pulse generator can be included within the outer jacket of the light source.

Abstract: A high intensity discharge lamp comprises a two-electrode arc tube and an external starting probe supported from a base and preferably sealed within an outer envelope to which the base is attached. The base contains an electronic pulsing circuit comprising a capacitor connected in a charging circuit across the base terminals, a pulse transformer having its primary connected in series with a voltage sensitive switch across the capacitor, and a step-up secondary connected to the probe. After starting, the voltage across the capacitor drops below the breakdown level of the switch and pulsing stops.

Abstract: A high pressure sodium vapor discharge lamp,characterized in thatits discharge tube contains xenon gas at a high pressure of e.g. over 150 torr, at least one of discharge electrodes has a projection conductor which is disposed extending therefrom towards an inside surface of a side wall of a tube envelope of the discharge tube in a manner that outer end of the projection conductor is disposed in proximity to a side wall of said tube envelope with a predetermined gap in-between anda starting aid conductor is disposed lengthwise on the outside surface of the side wall, and connected to the other electrode.

Abstract: High-pressure discharge lamps, having a sealed discharge vessel surrounded by a sealed glass envelope, are known in which an oxidizable metal foil (e.g. of molybdenum) is located, in the space between the vessel and the envelope substantial on the axis of the vessel and is electrically in series with the discharge path. If the envelope is fractured for any reason and the lamp is subsequently ignited, the temperature of the foil is increased due to the discharge current passing through it. The foil is oxidized, and hence fractured, by the air which has permeated said space and the lamp is, extinguished. Such oxidation and fracture normally takes about ten minutes. In accordance with the invention, the foil (14) in the space between the envelope (1) and vessel (2) is arranged close to the wall of the vessel adjacent to an electrode (6) so as to be heated mainly by heat generated in the vessel. This reduces the fracturing time to about one minute.

Abstract: An HID lamp has a very positive acting and simple resilient safety switch positioned proximate the inner surface of the bulb portion of the protective outer envelope and in contact therewith which maintains the switch in a closed position. When the envelope is shattered, the closed switch will open to break the electrical path to the arc tube, thereby rendering the lamp inoperative.

Abstract: The inner arc tube of some jacketed discharge lamps transmits ultaviolet radiation which is normlly 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 a springy conductor fastened to a conductive support and compressed between the outer envelope and an arc tube inlead. Upon fracture of the outer envelope, the conductor straightens out whereupon the circuit is opened and the arc tube is disabled.

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 safe "phantom" lamp structure for replacing a fluorescent lamp in a two-lamp series circuit connected fluorescent fixture which permits the remaining lamp of the two-lamp fixture to operate. The structure includes, in different embodiments, one or more magnetically or thermally actuated switches which must be closed for completion of the phantom lamp circuit and the switches are closed only after connection of both ends of the phantom lamp to the appropriate fixture sockets.

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: An HID lamp utilizes a thin, fragile, strip-like conductor member affixed to and carried on a portion of the inner surface of the lamp protective envelope. Upon breakage of the protective envelope, the fragile conductor will break and interrupt the electrical continuity of the lamp's electrical circuit, thereby rendering the lamp inoperative.

Abstract: A combination lamp comprises a miniature arc tube, a standby filament and a thermal switch in a sealed vitreous envelope. The switch is connected in series with the filament, and the arc tube and the filament have separate inleads for external connections. The switch is closed at room temperature, allowing the filament to light up immediately at a cold start and providing an instant-on feature. During normal operation, heat and light radiated by the arc tube cause the switch to open and turn off the filament. The small size of the arc tube favors a heat balance which allows the thermal switch to cool and reclose quickly in the event of a current interruption, thereby assuring lighting after an acceptably brief delay in the event of a hot restart.