Abstract: A battery charger failure alarm circuit for use with a battery charger including a source of rectified AC voltage for charging a battery and a filtering inductor serially interposed between said charger circuit and battery and across which there appears AC ripple voltage so long as the battery charger is functioning properly, includes a sensing circuit coupled to the filtering inductor for sensing the presence of the AC ripple voltage and an alarm circuit coupled to the sensing circuit operable to indicate the failure of the battery charger circuit in response to a lack of sensed AC ripple voltage. A time delay circuit may be included in the battery charger failure alarm circuit between the sensing circuit and alarm circuit to delay the operation of the alarm circuit in the case of momentary loss of the AC ripple voltage.

Abstract: An electromechanically controlled switch assembly including an automatic, three position, removable, transfer switch and a three position, manually operated bypass switch assembly. Electromechanical controls are utilized to sense the position of both switches, including whether or not the bypass switch is being manually switched to the normal or an emergency source of power, whether or not the power sources are available, and whether or not the transfer switch is properly located within its supporting frame for normal operation, completely isolated, or isolated from the load but in the correct location for testing.

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: The invention relates to a method for improving the thermal stability and dielectric integrity of a cellulosic web product. The cellulosic web is impregnated with a nitrogen donor compound such that the web contains not less than 0.2% by weight of the compound and thereafter impregnated with an aqueous vegetable protein solution at a pH of not less than about 8.5.

Abstract: An overcurrent relay circuit has a power supply developed from a test signal representative of the current in the line being monitored. The power supply is a Zener diode and capacitor arrangement connected in series with the load or test resistor. A variable time-current characteristic circuit (or timing plug) is based upon a variable effective capacitance circuit in which the timing capacitor and resistor currents are isolated from, but dependent upon, one another.

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: 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: An improvement to fault responsive protective devices, which employ timing capacitors, is provided by controlling the voltage of the timing capacitor by clamping it to a value slightly in excess of the voltage on a master timing capacitor. This allows the master timing capacitor to inhibit the operation of the improved fault responsive device without affecting the input to the timing capacitor. The inherent time constant produced by the timing capacitor is not altered. However, by clamping the voltage level of the timing capacitor only under appropriate conditions, the time current characteristic of the improved fault responsive protective device is altered only when those conditions occur which make it desirable to lengthen the interval before the fault responsive protective device responds to a fault.

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 operating mechanism for a fluid blast circuit interrupter which is actuated by a single drive shaft and includes a toggle linkage for opening and closing the breaker contacts, and a cam and rachet assembly for opening and closing a gas supply valve. Upon initiation of an opening or closing operation, the cam is coupled to the drive shaft and rotated to open a normally closed, spring loaded, gas valve before the interrupter contacts are opened or closed, and to charge a cam return spring. After the interrupter contacts are fully opened or closed, the cam is disengaged from the drive shaft and returned to its neutral position by its return spring to allow the gas valve to reclose.

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: 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 high speed vertical axis floor treating machine for polishing, brushing or scrubbing a floor includes a frame, a drive motor on the frame for rotating a floor treating element, a control handle pivoted to the frame, and a pair of ground engaging wheels mounted on an axle. The frame is resiliently supported on the axle to permit edging of the floor treating element. An adjustment rod engaging the axle raises and lowers the frame on the axle. The drive motor is mounted rearwardly of the axle to counterbalance the weight of the floor treating element about the axle.

Abstract: An electrical apparatus, such as a capacitor, having an improved dielectric system. The capacitor includes alternate layers of metal foil and dielectric material which is impregnated with 1,1-bis(3,4-dimethylphenyl)ethane. The capacitor has improved corona characteristics and low dielectric losses. The liquid dielectric is biodegradable and environmentally acceptable.

Abstract: A power cord storage device for electrically powered apparatus, such as a vacuum cleaner having a control handle, includes a first pin, an arm rotatably supported on the handle and including a hub portion defining an L-shaped slot within which the pin extends, another arm secured to another leg of the handle and being rotatable to a first position so that the pin may be positioned in one leg of the slot and the power cord may be wrapped around the arms. The hub may be shifted to place the pin in the other leg of the slot to release the power cord.