Abstract: A battery charging system having a charger control circuit which monitors one cell of a battery bank and controls the operation of a charging current source in accordance with the terminal voltage of the monitored cell. The charger control circuit includes an overcharge sensing circuit and a shorted cell sensing circuit, each being capable of triggering a separate output driver to interrupt current flow from the charging current source to the battery bank. The overcharge sensing circuit employs a time delay network to avoid nuisance charger system interruptions. The shorted cell sensing circuit also employs a time delay network to allow charging of heavily discharged or zero voltage batteries.

Abstract: A light fixture housing includes upper and lower members. The upper member includes a top bounded on four sides by a wall and the lower member includes a bottom also bounded on four sides by a wall. The walls of the two members define four corners of the housing. At each of the corners in the upper member a tang with an inclined leading ramp is formed on the inner peripheral surface of the wall and is flanked at two sides by a guide. At each of the corners of the lower member and upstanding tongue extends above the wall and includes an aperture for receiving the tang when the upper and lower members are assembled. A slot is located in at least one of the corners of the upper member adjacent to the locking tang and a notch is formed in the upper end of at least one of the tongues such that a power line may be threaded through and held within the slot. To assemble the housing, the upper and lower members are positioned together and each of the tongues is positioned within a set of guides.

Abstract: An arrangement for mounting a thermal protective device including a case in which there is mounted a temperature sensitive element, in a lighting fixture adapted for recessed mounting in a ceiling support surface, includes a receptacle dimensioned for receipt of the thermal protective device. The receptacle is mounted on the interior surface of the side wall of the recess mounted housing of the lighting fixture. The housing side wall defines an aperture predeterminedly located therein with which the temperature sensitive element is aligned for sensing the temperature of the area adjacent the exterior surface of the housing side wall. The receptacle includes fingers for biasing the thermal protective device into engagement with the interior surface of the housing side wall. The receptacle is constructed of reflective material to reflect heat emanating from the lamp of the lighting fixture away from the thermal protective device.

Abstract: A shock absorptive magnetic mounting support for a light fixture or the like object includes a base having a magnet mounted thereon for magnetically securing the mounting support to the underside of a metallic shelf or support surface. A support shaft upon which the light fixture is mounted has a threaded end portion received in an aperture in the base. A stop adjacent the threaded end portion limits the insertion thereof into the aperture. A rubber washer of a predetermined thickness is received on the threaded end portion of the shaft in abutting relation with the base. A nut, and, if desired, a lock washer, is received on the threaded end portion of the support shaft. The nut is tightened down against the rubber washer to secure the base and support shaft in a joined condition. The shock absorptive arrangement aids in preventing detachment of the magnetic base from the metallic shelf support in the event of the application of force to the upper side of the shelf.

Abstract: A voltage regulating transformer utilizing a microprocessor and a versatile multipurpose set of hardware modules and software modules it is described. A standard tap changing mechanism is driven in response to an analog control signal to change the output voltage of the transformer in response to digitally sampled values of voltage and current which have been transformed from the time domain to the frequency domain through a software program using Fourier transform techniques. The output current is also transformed and digitally processed to determine the power factor and the direction of power flow through the transformer. By inserting the digital values of the line characteristics to the load, line drop compensation is provided for. The difference in voltage across the input and output transformers is transformed to a digital signal and internally processed to provide an indication of the position of the tap changing mechanism without relying upon mechanical devices.

Abstract: A plaster frame for mounting a lighting fixture in recessed fashion in a ceiling comprises a main body portion including a rectangular, planar member defining an aperture therein, the aperture being similarly dimensioned to the ceiling aperture in which the lighting fixture is to be mounted. Hanger bar brackets are integrally formed with the planar member at breakaway junctions along opposite, first sides of the planar member. The hanger bar brackets are adapted to receive hanger bars for mounting the plaster frame between spaced joists supporting the ceiling. Each hanger bar bracket is removable from the planar member by bending at the breakaway junctions. The hanger bar brackets are reattachable to the planar member along opposite, second sides thereof by means of bendable, spaced tabs formed on the brackets receivable in similarly spaced apertures defined in the planar member.

Abstract: A high vacuum fluorescent display device contains solid state drive circuitry within a unitary evacuated container.

Abstract: An in-line fuse holder capable of handling currents as high as 30 amps, adapted to accept miniature, relatively flat, plug-in fuses which have a pair of flat terminals and a fuse link visibly retained within a relatively flat plastic case. The in-line fuse holder has a relatively rigid casing in which a pair of generally U shaped contact clip assemblies are mounted for receiving the flat terminals of the plug-in fuse. The contact clips are of two piece construction with an inner clip of highly conductive material and an outer clip of highly resilient material. The outer clip fits over the inner clip to force the inner clip into low resistance contact with the fuse terminals.

Abstract: The invention relates to a composition for an opaque coating for minimizing the light output from selected areas of an incandescent lamp, particularly a halogen lamp. It has been discovered that a paste comprising a mixture of sodium silicate and manganese dioxide, when thinned with water to a desired consistency, then applied to the external surface of a halogen lamp bulb and properly dried, forms a tightly adhering, opaque coating of dark gray color which resists flaking and blistering at operational temperatures of the halogen lamp.

Abstract: A current limiting fuse has a main fusible element and an auxiliary fusible element each helically wound over an insulative support member. Each end of the auxiliary element is connected to conductive metal clips or electrodes in which blocks of metal oxide varistor material are fixedly secured and placed in contact with the main fusible element. Subsequent to the initial burn back of the main fusible element, the metal oxide varistors precisely initiate electrical arcs between the terminal clips at the ends of the auxiliary fusible element and the main element at points adjacent to these terminal clips. The presence of these arcs quickly sever the main element or elements at these points thereby producing additional burnback areas in the main fusible element or elements.

Abstract: The invention relates to a base for a cartridge lamp of the type having at least one filament mounted on filament support legs extending through a seal of the bulb. According to the invention, a plug member has terminals affixed thereto for mounting the filament support legs. The plug member is adapted for keyed insertion into an opening. The terminals extend beyond the plug surface to form tangs which act as clamping fingers. The tangs also serve for contacting the connecting leads after the plug member has been rotated into a locking position.

Abstract: A circuit interrupting device responsive to externally generated heat and method of manufacture of such device. The device includes a pair of spaced, coaxially aligned leads each entering a thermally conductive housing from an opposite end. The inserted ends of the coaxially aligned leads are bridged by a conductive member comprising the tail of a conical spring which surrounds one of the leads and is secured at a corresponding end of the housing. The circuit-completing spring tail is secured by fusible material to the inserted ends of each of the spaced-apart leads. In a normal, closed circuit condition, the spring is under tension. Upon heating, the fusible material softens, allowing the spring tail to break away from the inserted ends of the spaced-apart leads, the retracting force of the conical spring, pulling the spring tail from the other one of the leads to open the circuit.

Abstract: An outdoor luminaire having a reflector adapted to provide uniform illumination of a relatively large, generally level surface. The reflector is comprised of a pair of side segments and contiguous concave top and bottom segments surrounding a light center. The top segment includes three cylindrical portions which are circular in section, the portion adjacent the top edge having its circular center well in front of the light center, while the other two circular cylindrical portions have their centers behind the light center. The bottom segment includes a transient portion and a cylindrical portion which is parabolic in section. The parabolic cylindrical portion is adjacent the bottom edge and has its foci at the light center. The side segments are tilted to reflect light from the light center directly out of the luminaire.

Abstract: This disclosure relates to the construction of butterfly valves of the type used for controlling fluid flow and, more particularly, to a seal for use in sealing the periphery of the closure member of such valves. Further, the seal disclosed herein is loaded by the pressure of the fluid being handled, to enhance the tightness of the seal.

Abstract: A multiple element current limiting fuse has a plurality of tube fuses soldered at opposite ends to a pair of metallic end bells having blade-like terminals for connection to busbars of an external electrical circuit. Fasteners having the general dimensions of the tube fuses are also mounted between the end bells and connectors, such as, studs or rivets are formed on ferrules at opposite ends of the fasteners to mechanically couple the fasteners to the end bells and preserve the spacing between the end bells even when the fuse is subjected to tensile forces and elevated temperatures efficient to soften the solder. The use of a hollow ceramic body and hollow connectors at the ends of the fasteners permits the passage of coolant through the fasteners for cooling the multiple element fuse.

Abstract: A multiple element fuse has a pair of end bells with terminals for connection to spaced apart busbars of an external electrical circuit. A plurality of tube fuses are mechanically fastened and soldered at opposite ends thereof to the end bells. The tube fuses have insulative tubular bodies with metallic ferrules attached at each end. The ferrules which are received in cavities defined in the end bells, include hollow studs for receipt in countersunk holes also formed in the end bells. The studs are flared and/or receive expansion plugs to mechanically attach the tube fuses to the end bells, thereby to preserve the spacing between the end bells even when the fuse is subjected to tensile forces created by the busbars and sufficient heat to melt the solder during fuse clearing.

Abstract: A tungsten filament lamp incorporates arc discharge electrodes for an arc discharge in a gas fill enclosed in the lamp envelope. The tungsten filament is utilized as a ballast resistance for the arc discharge. A method for mounting the filament and electrodes in an embodiment according to the invention is shown.

Abstract: A vehicle headlamp is provided wherein one or more reflectors scan a collimated beam of light to generate a desired light beam pattern and project it to the road. Electrical and mechanical driver means are also provided to change the mode of operation of the scanning reflector to change the pattern of light and its location on the road.

Abstract: The invention relates to a socket for a baseless cartridge lamp, particularly a two-filament cartridge lamp or a cartridge halogen lamp with contacts at opposite ends thereof.