Abstract: The invention relates to a method and apparatus for checking the internal pressure of a filled lamp bulb. According to the invention, a filled bulb to be checked is inserted into a gas tight chamber; the chamber is then sealed and pressurized. The lamp envelope is broken by means in the chamber. Chamber pressure is measured before and after breaking the envelope.

Abstract: The invention relates to vacuum fluorescent devices having a grid element positioned between the filament and fluorescent anodes of the device. An insulating material on a portion of the grid is effective to reduce grid current and to enable achievement of greater brightness of fluorescence from the fluorescent anodes.

Abstract: An automatic voltage regulating transformer is provided which incorporates a potential transformer electrically disposed across its series windings, and a set of sensing windings disposed across its shunt windings to provide a voltage sensing network which is responsive to the flow of current both into and out of the transformer. The output of the potential transformer is connected in series with the sensing windings to provide a control voltage which is representative of the voltage across the shunt windings and series windings taken together. In the case of a normal voltage regulating transformer, this control voltage is proportional to the voltage across the output terminals. In the case of an inverted regulating transformer, the output voltage of the voltage sensing network is proportional to the voltage across the input terminals.

Abstract: A floor scrubbing apparatus including a combined solution and recovery tank is disclosed. The floor scrubber is of the type including a brush head, a squeegee and a vacuum system. A combined solution and recovery tank is operably connected to the vacuum system and the brush head. The tank is a one-piece, rigid integrally molded member having an inner wall and outer, spaced wall. The inner wall defines a recovery tank and the outer wall surrounding the inner wall defines therewith a solution tank. The one-piece member further defines an inlet opening, a solution drain opening, a recovery drain opening and a solution outlet tube.

Abstract: A rechargeable flashlight fits into and draws recharging power from an automotive type cigar lighter socket. A thermally controlled charging circuit within the flashlight adjusts the charging rate according to the ambient temperature. When the flashlight is withdrawn from the cigar lighter socket, it is illuminated; when it is replaced it is extinguished. Alternatively, the flashlight may be manually illuminated or extinguished outside the charging socket.

Abstract: A conductor support is provided for use with high voltage electrical devices having mounting walls with apertures formed therein through which electrical conductors pass. The conductor support is formed of first and second channel members sequentially inserted in the mounting wall aperture. The first channel member includes walls bendable toward and away from each other, corresponding to collapsed and expanded configurations of the first channel member, respectively. The first channel member is collapsed to take on a reduced cross sectional area, and is inserted through the aperture of the mounting wall. The first channel member includes retaining members, such as notches or grooves, for engaging the mounting wall. After insertion, the first channel member is expanded to bring the retaining members into engagement with the mounting wall.

Abstract: Compact bodies for use as contacts in vacuum current interrupters, plasma devices and the like are formed by a vacuum hot press fabrication of suitable powder material. The contacts which may be formed as a button or ring, are operable under high current arcing conditions. The powder material is mixed and placed between a pair of rams in a floating die cavity maintained in an inert atmosphere and is placed in a vacuum chamber. A vacuum is created without pressurizing the powder material. The powder material is heated to below its melting temperature for degassing. The die cavity preferably includes special outgassing ports. The rams are pressurized and the powder material reaches a sintering temperature and a vacuum of 3.times.10.sup.-6 torr. A uniform composition compact body essentially devoid of trapped gas and particularly suitable for use as a high current interrupting contact in an arcing environment results.

Abstract: A dual element, time delay fuse with greater blowing time accuracy and improved operating characteristics wherein any bridging of the circuit opening air gaps by molten alloy is effectively precluded during operation of the fuse, especially operation initiated by small protracted overloads. This is accomplished with a fuse element assembly comprising a series connection of a short circuit member, a central absorber member and a heater element member, the central absorber member held to the short circuit member and heater element member by masses of fusing alloy on each of its ends, which masses of fusing alloy are prevented from combining in fabrication and circuit opening operation by flow restricting apertures located near each end of the absorber member.

Abstract: A power class fuse comprises an insulative canister having a female load break contact at a closed end of the canister and a male load break contact, coupled electrically to a fuse element. The male load break contact is inserted into the canister for engagement with the female load break contact to complete a circuit through the fuse element. An arc gas control device including a pair of spaced parallel plates each having apertures formed therethrough and filter material sandwiched between the plates, is mounted on the male load break contact. The arc gas control device forms a partition in the canister upon insertion of the male load break contact thereinto. Arc gas generated upon engagement of the male and female load break contacts passes through the control device into the canister interior surrounding the fuse element to reduce back pressure in the canister, while metallic particles and other contaminants which could produce flashovers within the canister, are trapped in the filter material.

Abstract: An electrical capacitor having an improved dielectric system. The capacitor includes layers of metal foil and a dielectric sheet material which is impregnated with a liquid dielectric composition composed of a mixture of methyl diphenyl ethane and a lower alkyl diphenyl.

Abstract: A secondary valve arrester for protection of secondary electrical systems, comprises a housing having a lid and base portion, the latter of which includes a plurality of compartments each of which is dimensioned to receive a valve block and spark gap assembly or a varistor assembly; the number of said assemblies included in the arrester corresponding to the number of phases protected in the system. Each said assembly includes connecting electrodes of similar construction, each connecting electrode having two offset male terminals and one offset female terminal for connection to externally connected lead wires or other connecting electrodes. The housing lid includes first and second rib sets for extension into the base portion to retain the said assemblies in a tightly stacked condition in respective compartments.

Abstract: A thermal protective device for interrupting current to the lamp circuit of an electrical lighting fixture when the temperature at a preselected location in the fixture reaches a predetermined level, comprises a receptacle including a pair of female terminals coupled electrically to the lamp circuit. A normally open switch having a movable contact arm with a hooked end portion is coupled to one of the terminals to maintain the lamp circuit normally open. A plug adapted for joinder with the receptacle includes a pair of male terminals arranged for receipt by the female terminals of the receptacle. A thermal protector included in the plug is operable from a closed to an open condition when the temperature reaches the aforesaid predetermined level. The thermal protector is connected electrically across the male terminals. An actuator and latch arm extending from the plug is received in the receptacle upon joinder of the receptacle and plug.

Abstract: A recrystallized copper billet in excess of one and one-half inches in diameter is formed as an essentially single-grain or crystal copper. A high conductivity, oxygen-free copper billet is subjected to mechanical surface cleaning and to a "bright dip" bath to chemically clean the surface. The copper billet is located in a similar sized graphite crucible and induction-heated in a vacuum chamber to a modest temperature for outgassing of said crucible. The heating is increased to melt the copper and then is reduced in steps to produce a copper equilibrium temperature about seventeen degrees centigrade above the melting point of the copper. A slow non-directional and natural cooling at the rate of about three to fifteen degrees per hour is created until total solidification and recrystallization occurs.

Abstract: A current limiting fuse construction including a fuse element extending between electrically conductive terminals carries a body of arc-quenching filler material within a hollow casing of electrical insulating material. The filler material includes a first portion of arc quenching aluminum sulfate mixed with calcium sulfate binder, and second portion of arc quenching silica sand arranged in stratified layers, with the aluminum sulfate layer being positioned closest to a weak spot of the fuse element, and the layer of silica sand being positioned closer to an end cap of the fuse casing.

Abstract: A rolling conductor support for supporting, guiding, and protecting electrical, hydraulic, coolant and the like conductors extending between parts of machines which move relative to one another on guides or tracks. The conductor support comprises a plurality of chains connected in parallel, laterally spaced relation by conductor supporting bridges to which the conductors are fastened by releasable securements. The chains are comprised of a series of alternating and overlapping follower links and control links, overlapping portions of which are pivotally connected to each other. Six holes are formed in each follower link, one at the center of each end for making a pivotal connection to the overlapping control link. The remaining four holes, having stop pins secured therein, are positioned in pairs at each end of the link adjacent the pivotal connection.

Abstract: A conductive bushing connector includes an elongated metal stud having a center axial passage, a plurality of transverse apertures, and threaded portions at each end. A pair of insulative housings assembled on opposite sides of a transformer enclosure each overlying the metal stud and abutting the wall of the transformer enclosure form a cavity surrounding the metal stud. A pair of threaded end terminals cooperate with the threaded end portions of the metal stud to secure the entire assembly. Each interface of the assembly is provided with resilient sealing members which are maintained in compression by the end terminals. The insulative housing within the transformer enclosure includes a plurality of fluid convection apertures.

Abstract: A pan for a ceiling mounted light fixture includes a saucer-like canopy defining a mounting hole for receipt of a fastener to secure the light fixture to a ceiling support surface. A first layer of insulative material is received between the canopy and the ceiling surface. Descending arms spaced about the periphery of the canopy join the canopy to a housing portion which is suspended therefrom. The housing portion includes concentric outer and inner walls, the latter of which has an inwardly extending lip or ledge defining a shelf to support a second layer of insulative material disposed between the canopy and shelf. Electrical sockets for receiving incandescent lamps are mounted on the lower wall of the shelf and a glass or the like shade is received thereover and secured by screws extending through the outer wall of the housing portion. The double layers of insulative material serve as barriers to prevent damage to the ceiling surface from heat generated by the incandescent lamps of the light fixture.