Abstract: A thickfilm manufactured resistive element that functions as a normal resistor in an HID lamp starting circuit where high voltage starting pulses are produced, but which exhibits a negative and extremely non-linear voltage coefficient of resistance characteristic when potentially destructive high voltage spikes occur as a result of circuit interruption during operation of the lamp. The resistive element is comprised of a mixture of refractory conductive, semiconductive, and nonconductive materials of an amorphous noncrystalline nature having the physical structure of a supercooled liquid, commonly referred to as glass, which has been discovered to exhibit the property of having an extremely non-linear voltage coefficient of resistance.

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: An improved light fixture comprising a housing adapted for tower or pole top mounting and having preferably stacked upper and lower lamp compartments. One reflector in each compartment includes a segment that is located partly behind and partly over a symmetrically positioned lamp included therein so as to reflect light therefrom downwardly and outwardly through a window in a side wall opposite to the reflector. Another reflector similarly located reflects light through a second window in an opposite side wall. Windows in the other two side walls also receive light emanations from the lamp. The axis to the lamp in each compartment is substantially horizontal and is skewed with respect to the side wall windows. The lamp in one compartment is preferably complementarily positioned with respect to the lamp in the other compartment.

Abstract: A circuit for energizing a gaseous discharge lamp at high frequency utilizing a thyristor, preferably an SCR. The energizing circuit for the lamp includes a resonant or tank circuit operating at an appropriate high frequency, preferably above the acoustic resonant frequencies of the lamp, and which also commutates an SCR. The cathode/anode of the SCR is connected to a voltage adjusting network to provide an initiating pulse through the SCR to start oscillations in the resonant or tank circuit when the SCR is gated on and which reduces the applied supply potential to the SCR during its conduction period to ensure non-conductive latching of the SCR when the gate thereto is removed by lengthening the natural commutation interval of the SCR. This permits the SCR to be used as a switch at the high frequencies involved, normally about 60 kHz.

Abstract: An enclosure for a light fixture and the method for making such an enclosure via the securement of a plastic or glass lens, wherein the light fixture has a window which does not have to be opened in normal use for replacement of bulb, but is normally accessible through a rear or side opening. The window opening is circumscribed with a front flange projecting radially outward. A double sided adhesive tape is affixed to the flange and is united with the lens. A metal cored trim covers and secures the flange and the unified tape-and-lens structure. This latter assembly may be further secured by crimping.

Abstract: A visual monitor including a single light indicator for HID lamps (not needing a starter) and a visual monitor including two light indicators for an HID lamp, such as a high pressure sodium lamp, operating in conjunction with the starter. When the lamp is out, the presence or non-presence of an ignited first light indicator indicates lamp failure or ballast failure, respectively. The blinking or nonblinking of the second light indicator indicates whether or not the starter is producing satisfactory starting pulses.

Abstract: An electronic controller for providing one or more sequences of control outputs for a plurality of controlled devices. The controller includes a pulser which produces pulses at the rate of the frequency of an ac source, a divider for producing spaced pulses preferably at one-second intervals, a counter for counting a large number of these spaced pulses and one or more PROM's. The PROM's select and actuate one or more sequences stored therein and produce controlling outputs on a plurality of lines to a plurality of controlled devices.

Abstract: A light reflector system for an elongated light source and having multiple reflective surfaces, some of which are treated for diffusing light, particularly those surfaces that reflect light at low reflective angles, and some of which are specular or, alternatively, treated for light spread reflection, particularly those surfaces that reflect the image of the lamp source at high reflective angles.

Abstract: A light fixture comprising parabolic reflector segments therein, the lamp being located at the focal point of the segments. One segment has an arc preferably more shallow than the other segment. The window opening is angled preferably at an angle of 60 degrees to the elongate axis of the parabolic segments to provide sharper light cutoff or less spill light from one reflector segment than from the other. A shield positioned parallel to the elongate axis and on the side of the axis within the reflector segment where the cutoff characteristics are the greatest, permits primary reflected light from the lamp, while preventing direct light from the lamp to pass above the shield. The specular underside of the shield enhances light reflection therefrom while the darkened top shield surface blocks secondary reflection above the cutoff angle.

Abstract: An improved light fixture for housing an elongated lamp and method for making same, the fixture having an elongated housing constructed from a continuous rectangular piece of sheet metal having four parallel bends therein forming planar side walls. The planar side walls form flange planes suitable for mating within grooves formed in suitable end pieces for the housing. The closure lens completes the housing. The construction of the elongated housing side walls is such that a reflector sheet when curvedly affixed to the two outermost planar side walls is tangential to the inner three planar side walls, thereby providing a parabolic reflecting surface for a lamp mounted within the reflector sheet. Two end wall reflectors, preferably one of which is directionally adjustable, also reflect luminous flux from the lamp.

Abstract: An enclosure for a light fixture and the method for making such an enclosure via the securement of a plastic or glass lens, wherein the light fixture has a window which does not have to be opened in normal use for replacement of bulb, but is normally accessible through a rear or side opening. The window opening is circumscribed with a front flange projecting radially outward. A double sided adhesive tape is affixed to the flange and is united with the lens. A metal cored trim covers and secures the flange and the unified tape-and-lens structure. This latter assembly may be further secured by crimping.

Abstract: Circuits are disclosed for use in a gaseous-discharge lamp lighting system which provide starting pulses to the lamp and/or a source of auxiliary light. One circuit provides starting pulses and/or auxiliary light until the gaseous-discharge lamp approaches its normal operating condition, while other circuits terminate these functions once the gaseous-discharge lamp ignites.

Abstract: A network for the development of a square wave in a first time period as set by the timing occurrence of a first voltage to a predetermined threshold level and another network for the development of a square wave in a second time period as set by the timing occurrence of a second voltage to a predetermined threshold level. One square wave is chopped at a high frequency rate and the second square wave is chopped at the same high frequency rate, but by a chopping signal which is polarity inverted in phase from the first chopping signal. One of the chopped signals is polarity inverted before being combined with the other chopped signal to form a composite voltage. Separate lamp control networks can select between the two chopped signals to control dimming networks. The two chopped signals can overlap in time occurrence without interfering with the operation of each other.

Abstract: A dimmer and regulation circuit connected to an incandescent lamp load for controlling the voltage thereto from an ac source by gating off a portion of each cycle. The circuit used to provide the gating includes a pulse generator controlled by a timer producing a rectangular wave output. The input to the timer is from an operational amplifier, the inputs to which are, in turn, from a variable control voltage setting and from a load sensing network including components for non-linear curve shaping processing, such as in accordance with the IES square law curve. These inputs operate in a closed loop feedback system to provide line and load regulation after the sensed load voltage passes through the square law shaping network. This non-linear network includes a half wave rectifier and a capacitor that is part of two time constant networks, and which accumulates a charge during one-half of a cycle through a first resistance path and which discharges through a second resistance path.

Abstract: A protection circuit for producing one or more triggers in the presence of a monitored overvoltage condition employing a complex voltage divider network including slow-acting breakover semiconductor devices for sensing ac voltage overloads in either or both polarities thereof, and operating gated semiconductors by controlling the voltages applied to both the gates and the main terminals thereof, which, in turn, discharge capacitors for trigger production. Monitoring may be with respect to supply voltage, power supply output voltage or one or more independent voltages.

Abstract: A regulation circuit for providing timing gate signals to the dc power section of a power supply, the regulation circuit utilizing phase angle conduction of a programmable unijunction transistor. The conduction angle is determined by the occurrence of the cycles of the ac source voltage unless earlier conduction is determined by the sensed dc voltage. Early conduction occurs when the control voltage to the PUT is allowed to build up beyond a predetermined level when the sensed dc voltage is low. When the sensed dc voltage is high, an electronic switch closes to discharge a storage element to prevent control voltage build up and, hence, early conduction. Ac source voltage failure also causes closing of the electronic switch to prevent undue regulation of the power section output at such times and to permit storage capacitors therein to maintain a dc output until source voltage is reestablished.

Abstract: A regulation circuit for providing timing gate signals to the dc power section of a power supply, the regulation circuit utilizing phase angle conduction of a programmable unijunction transistor. The conduction angle is determined by the occurrence of the cycles of the ac source voltage unless earlier conduction is determined by the sensed dc voltage. Early conduction occurs when the control voltage to the PUT is allowed to build up beyond a predetermined level when the sensed dc voltage is low. When the sensed dc voltage is high, an electronic switch closes to discharge a storage element to prevent control voltage build up and, hence, early conduction. When there is an ac source voltage outage, a diode connected to the control voltage output conducts to keep the control voltage to zero and hence closing of the electronic switch to prevent undue regulation of the power section output at such times and to permit storage capacitors therein to maintain a dc output until source voltage is reestablished.

Abstract: A circuit for providing a dc pulse, such as to a gated semiconductor for at least partial bypass of a ballast element connected to an HID lamp, the pulse being developed within a time range of an associated ac voltage. A first timer operably connected to the ac voltage produces a first dc output pulse and a second timer connected to the output of the first timer produces the circuit dc pulse output. Reduction of a threshold control voltage of the first timer permits a time constant network connected thereto to advance the conclusion of the output of the first timer forward within its operational range. A time constant network connected to the second timer has charge current added to it from the first timer control voltage, the amount of such current decreasing with an advance positioning of the output of the first timer, thereby increasing the slope of the charge-up voltage of the second time constant network and shortening of the related square wave or dc pulse output from the second timer.

Abstract: A dimmer circuit for a high intensity, gaseous discharge lamp having a ballast with a reactive portion, the current bypass or partial bypass of which determines the brightness of the lamp, the bypass being controlled by gated bypass means, preferably in the form of a triac, driven by the photodrive element of an optocoupler, the light emitting diode element of the optocoupler receiving pulses and actuating the photodrive element for passing a gate trigger signal to the gated bypass means.

Abstract: A dimmer circuit for providing gate signal to a gated semiconductor connected for at least partial bypass operation of a ballast element of an HID lamp, the gate signal being derived from a high frequency voltage in a predetermined range. The high frequency voltage is separated from other frequencies and converted to a voltage proportional to the frequency. The voltage is then converted to a pulse within the timed operational limits of the line voltage for gating the semiconductor, and hence producing a brightness of the lamp between predetermined limits of full dim to full bright. Preferably, the high frequency voltage carrying the control information arrives superimposed on the line voltage to thereby avoid having to use a separate set of leads to the lamp to provide light level control signalling.