Abstract: A waveguide having reduced windloading yet a relatively wide bandwidth for the dominant mode of propagation comprises an elongated cylinder having substantially parallel plates forming an interior waveguide portion which in cross-section is a doubly-truncated circle. The plates are symmetrically disposed about the central axis of the elongated cylinder.

Abstract: A stress-relieving material for the surface of an insulated electrical conductor consists essentially of a cold-flowable, low viscosity, corona-resistant elastomer containing from about 350 to about 600 parts by weight per hundred of elastomer of a semiconductor material and up to about 10 parts per hundred of elastomer of processing aids.

Abstract: A self-threading and tensioning device for use with a semiconductor bonder, or the like, is disclosed. A first pneumatic stream is used to obtain the self-threading of the thin (e.g. 1 mil.) bonding wire. A second pneumatic stream provides the tensioning of the wire during the bonding process.

Abstract: A vacuum furnace is provided with subatmospheric pressure control of a diffusable media and with a fan at an end of a heated load chamber to circulate uniformly the diffusable media around the workpieces which are contained within the load chamber.

Abstract: A material heating furnace with a heating element formed of corrugated metal strips which are spaced at one of the ends thereof by a jumper strip which is welded or otherwise fastened to the metal strips. Also, terminals are provided which are slotted so as to alleviate stresses due to bending.

Abstract: A magazine and driving means particularly adaptable for handling semiconductor lead frames, or the like, in an automatic processing device such as a bonder is described. The magazines slidingly engage buttons on the front panel of the bonder or other device. In-line teeth defining a rack are formed on the exterior of each of the magazines. The magazines are driven directly by indexing pins which are connected to a geneva movement. Missing teeth at the ends of the racks allow the magazines to feed-through, thus providing automatic, uninterrupted operation from magazine-to-magazine.

Abstract: A height sensor is disclosed which permits a tool to sense the height of a semiconductor die, or the like, above a work surface such as a bonding table. A tool arm moves transverse to the work surface and is interconnected to a cam by a second arm. The second arm is disengageable from the first arm and disengages the first arm when the tool contacts the semiconductor die. Sensing means are provided to detect the separation of the two arms.

Abstract: A circuit is provided for providing a regulated d.c. output of a substantially high output current magnitude from an unregulated single or polyphase a.c. input source. Regulation is provided by a single feedback circuit interacting with a plurality of ferroresonant transformers connected in parallel to a single phase source, singly on each phase or a polyphase source, or interconnected in the known Scott T connection on a three phase source. Regulation is accomplished with thyristor switches which are synchronized with the input phase of each transformer.

Abstract: An electric heating furnace which includes a conductive electric resistance heating element strip mounted within a chamber defined by walls of porous refractory insulating material. Terminal or mounting pins extend through the wall of insulating material and the heating strip are secured thereby. A sleeve of non-porous refractory material surrounds the portion of the pin within the wall of insulating material for electrically insulating the pin from the porous refractory wall material which may have a conductive layer of carbon build up therein under certain heat treating conditions.

Abstract: A meter panel is formed from one or more meter modules, each of which has a plurality of horizontal line buses extending therethrough with the ends of the line buses being connectable to corresponding line buses in an adjacent meter module. Each meter module comprises an enclosure and a meter section removably mounted into an opening in the front face of the enclosure. The meter section has a plurality of vertical buses which are electrically connectable to horizontal line buses. The meter section has meter sockets therein with each socket having a plurality of electrical contacts into which meters may be plugged.

Abstract: An electrical receptacle having a body with upper and lower molded plastic portions with a grounding strip located in a cavity therebetween, the lower portion having extending mounting strap ears and the grounding strip having a connection extending under one of said ears for making contact with a holding screw, said grounding strip also having a visible connection tab.

Abstract: A strap for mounting an electrical wiring device in a mounting box comprises a yoke member having laterally projecting tabs on each end thereof, the tabs being fastened to the mounting box. A pad of electrically insulating material is positioned upon the tab so as to be interposed between the tab and the mounting box when the strap is mounted. The tab and pad are each provided with a slot through which a mounting screw passes, and the portion of the pad defining the slot has a beveled aperture with resilient lips so as to engage the threads of the mounting screw received in the slot to prevent movement of the mounting screw with respect to the strap and to insulate the strap from the mounting box.

Abstract: A lead wire capillary bonding tool formed from a rod with a core, the rod having a shaped end upon which tungsten carbide or refractory metal is vapor deposited and then the core removed.

Abstract: A constant voltage, constant frequency, uninterruptible a.c. power supply having a line voltage regulator, a rectifier-inverter with an emergency battery power supply and a transfer switch for selectively connecting the line voltage regulator and rectifier-inverter to a load. Under normal conditions, the line voltage regulator and rectifier inverter derive their operating power from the power line and are both connected to the load. If the fault detection system detects a power line fault, it causes the transfer switch to disconnect the line voltage regulator from the load and the rectifier-inverter supplies power to the load from the emergency battery power supply. If the fault detection system detects a rectifier-inverter fault, it causes the transfer switch to disconnect the rectifier-inverter from the load. A synchronization control system regulates the phase of the rectifier-inverter.

Abstract: An apparatus for the edge heating of sickle blades having a pair of magazines for retaining a vertical stack of blades therein, a pair of heat-treating stations located inwardly of the magazines and a discharge chute between the stations. A guide and rod assembly is reciprocated by an eccentric between two positions for feeding a blade from a magazine to a heat-treating station and removing the treated blade from the heat-treating station to discharge the blade into a discharge chute.

Abstract: The roof of the heating chamber in a refractory furnace is made of refractory or brick with vertical holes therein and a number of hooks or holding means are suspended in these holes. The hooks project into the heating chamber and an electrical heating element means is suspended on the hooks. In order to remove the heating elements, a plastic bag is used which has its open edge fastened to the top surface of the furnace to enclose an opening in the furnace through which the heating element and the bricks or holding means to which the heating element is attached can be withdrawn. The bag is of sufficient size to enclose the entire assembly when withdrawn from the furnace. The parts are arranged so that another element can be placed in the furnace by another bag so that gaseous contents of the furnace are kept in the furnace.

Abstract: A material heat treating system having a plurality of integral quench furnaces and means to convey material to be treated thereto in a selected pattern operated by controllers into which selected patterns of treatment are fed. The controllers feed signals to a selected furnace to control operation thereof in a selected manner and also provide signals to control movement to, from and through the system in accordance with a selected program.

Abstract: The roof of an elongated heating chamber of a refractory walled industrial furnace includes a plurality of transverse rafters which are spaced along the chamber, and each rafter is formed of a pair of arch bricks and an arch key brick between the inner ends thereof. A plurality of longitudinally extending roof bricks are supported between successive rafters by the means of notches in the ends of the roof bricks which rest upon horizontal surfaces defined on the central portion of each rafter.

Abstract: A line isolation monitor for detecting faults of lines isolated from ground in which a constant current generator generates an electrical signal having one or more frequencies near the power line frequency and applies the electrical signal to the power lines. A signal sensor detects the generated electrical signal on the power line and a discriminator determines the effect of the phase angle of the impedance from each of the power lines conductors to ground and the effect of the relative magnitudes of each of the conductors impedance to ground to detect a fault. A threshold circuit generates an alarm signal if the current flow is above a predetermined level, to energize audible and visible alarms.

Abstract: A mounting strap for mounting an electrical wiring device, such as a switch, having apertures at both ends for receiving mounting screws. The apertures have resilient lips which engage the threaded portion of the screws to prevent the free movement thereof. The mounting strap is adapted to fit on a mounting box with the electrical wiring device located within the mounting box.