Abstract: Low voltage electric switchgear equipment includes a central programmer unit electrically interconnected with electronic main and branch circuit interrupters within the same enclosure and used with a multi-phase power distribution circuit. Indicating diodes are arranged on each of the circuit interrupters for signaling the occurrence of an overcurrent condition. The same indicating diodes are arranged for responding to address commands generated by the field programmer as to the exact location of each circuit interrupter within the enclosure.

Abstract: An electronically reconfigurable digital pad attenuator is disclosed using selectively controlled segmented field effect transistors in a passive, non-gain state as the principal impedance elements. The attenuator may be fabricated in the monolithic microwave integrated circuit (MMIC) format with a segmented gate field effect transistor being connected in each of the separate branches of a Pi pad, Tee pad, or Bridged Tee pad attenuator configuration. The individual FET segments are maintained in a high admittance "ON" state or a low admittance "OFF" state in accordance with the binary control potentials applied to the gate of each segment, the principal electrodes being maintained at a zero potential difference. The attenuation then becomes a function of the binary gate potentials applied to each segment and assumes one of a set of well-defined discrete values. The attenuator consumes minimum power, provides attenuation steps that are independent of GaAs MMIC fabrication process tolerances, i.e.

Abstract: A conductively enclosed hybrid integrated circuit assembly for use with microwave and millimeter wave signals is disclosed. The enclosure utilizes a silicon substrate into which recesses are formed by conventional silicon etching processes to support individual MMIC chips with their surfaces flush with the unetched substrate surfaces. The assembly is covered with a thin solid dielectric layer, perforated over points of connection and followed by a metallization to provide point-to-point connections. The arrangement provides one or more levels of patterned metallizations with additional levels being provided either by additional dielectric layers or by forming the silicon substrate from three or more laminar elements and providing a patterned metallization on the surface of an intermediate element. Efficiency in signal grounding and in rf transmission line paths is assured by surface metallizations and the provision of low impedance paths through the substrate.

Abstract: A compact molded case circuit breaker with increased ampere rating employs a latch assembly for maintaining the circuit breaker operating mechanism in a closed condition against a pair of powerful operating springs. To increase the mechanical advantage required to move the operating handle against the springs, a retractable handle extender is attached to the handle. For higher-rated circuit applications, a lug cover extension is added to the line end of the breaker to assist in extinguishing the intense arc that occurs during circuit interruption and to protect the line lugs from inter-phasal circuit faults. A visual access slot is arranged next to the circuit breaker handle to ascertain and verify the condition of the circuit breaker contacts.

Abstract: Mercury condensation in dual phosphor layer fluorescent lamps is inhibited by mixing alumina particles having a median particle size not less than about one-half micron with the phosphor particles in the first phosphor layer which is disposed adjacent the inner lamp envelope surface.

Abstract: A compact single branch circuit breaker insulative support used within lighting panelboards is converted from an existing double branch support with minor alterations. The single branch circuit breaker arrangement allows the circuit breakers to be arranged in a closely-packed configuration within the lighting panelboard enclosure.

Abstract: An integrated protection unit is a circuit interrupter which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. An actuator-accessory unit arranged within the interrupter cover interacts between the actuator-accessory unit and the interrupter operating mechanism to separate the interrupter contacts and interrupt a protected circuit.

Abstract: This lighting fixture enclosure comprises a back housing and an adjacent front housing separable from the back housing. The back housing includes a base; and the front housing includes a cavity in front of the base and a wall partially surrounding the cavity and terminating in a free end adjacent the base. The back housing includes a cradle on said base for receiving a peripheral portion of one end of a wire feed-through conduit. The front housing includes a notch in the free end of said wall for receiving another peripheral portion of the conduit. A projecting leg on said front-housing wall receives clamping means which, upon operation, forces the front housing toward the back-housing base, loading the leg in a bending mode, and also clamping the conduit end between said cradle and the wall portion bordering the notch.

Abstract: The invention relates to molecular beam epitaxial (MBE) processing and more particularly to a two zone electrical furnace for use with high vapor pressure II-VI materials. The furnace is designed for use with effusion type crucibles requiring a lower temperature in the fill zone to control the flux and a higher temperature in the orifice zone to avoid clogging the customary collimating orifice. Each zone is heated by a distributively heated radiator, the fill zone radiator being of a tantalum foil construction of low thermal conductance, while the orifice zone radiator is a solid molybdenum cylinder of relatively high thermal conductance. The zones are joined by linking the two radiators by a thermally conductive path, while the shields and the distributed heaters of the respective zones are separated to reduce thermal coupling. The arrangement provides substantial independence between the temperature settings of the two zones and the molybdenum construction is free of erosion from tellurium based reagents.

Abstract: A mount for a minature lamp terminating at one end in an elongated tubular member, said mount comprising a base and a cap assembled in mating engagement and exerting a compressive force on at least one deformable, elastomeric tubular or ring shaped member in said mount which surrounds and contacts said tubular lamp member of which at least a portion of which is inserted in a bore in the mount, thereby holding the lamp in the mount.

Abstract: An operating handle assembly for molded case circuit interrupters is robotically assembled to the circuit breaker operating mechanism without requiring any auxiliary fastening device. A visual access slot in the circuit breaker cover allows the condition of the circuit breaker contacts to be visually ascertained by use of colored indicia carried by the operating handle skirt. A slidably mounted handle shutter cooperates with the operating handle to prevent egress of arc exhaust gases in the event the circuit breaker contacts are closed or opened during overcurrent conditions when the circuit breaker is installed within an industrial power distribution circuit.

Abstract: An integrated protection unit is a circuit interrupter which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. One such accessory used with the integrated protection unit is a bell alarm for indicating the status of the circuit interrupter contacts.

Abstract: Tungsten-halogen lamps operating at temperatures above 250.degree. C. which contain a mixture of phosphine, hydrogen, bromine and inert gas have been found to have superior life and lumen maintenance when the atomic ratio of phosphorus to bromine in the lamp is in the range of from 0.4-2.5.

Abstract: An electric lamp fabricated from lamp tubing and terminating at one end in an elongated tubular portion which is of a precise, predetermined length with respect to the optical center of the lamp is inserted directly into and held in a bore in the rear of a reflector so that the optical center of the lamp is at the focal point of the reflector without need for adjusting the position of the lamp in the reflector.

Abstract: A compact circuit breaker containing an electronic trip unit employs an actuator-accessory unit to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts to interrupt current within a protected circuit. A tolerance compensating spring is attached to the actuator-accessory unit trip armature to precisely set the separation gap between the tip of the armature and the actuator-accessory trip actuator arm.

Abstract: An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with supplemental trip and reset interface components. The reset mechanism allows the actuator-accessory unit to become reset without interfering with the operation of the integrated protection unit. The trip interface components allow the circuit interrupter to interrupt a protected circuit by operation of the actuator-accessory unit.

Abstract: An electronic circuit interrupter includes an electronic trip circuit contained within a circuit interrupter enclosure along with an externally accessible rating plug for setting the ampere rating. The rating plug includes keying tabs that fit within corresponding keying slots formed on the top surface of the electronic circuit interrupter enclosure. Interlock is provided between the rating plug and the electric panelboard which includes a plurality of electronic circuit interrupters connected within an industrial power system. Tabs formed on the side walls of the rating plug are trapped under the panelboard face plate to prevent removal of the rating plug without first removing the panelboard face plate.

Abstract: A molded case circuit breaker employs a multiple latch assembly for maintaining the circuit breaker operating mechanism in a closed condition. The multiple latch assembly includes three separate latch levers mounted on a common latch support frame. The multiple latch arrangement substantially reduces the amount of tripping force required to articulate the circuit breaker operating mechanism.