Abstract: A high dynamic strength or fatigue resistance is achieved in a taper thread reinforcing bar splice for use in steel reinforced concrete by coordinating the elongations of the coupler sleeve and bar to achieve the required movements of the coupler sleeve at the mouth. This is accomplished in the preferred embodiment by two attenuation grooves on the outside of a circular cylindrical coupler body at each end, each groove being placed in a particular axial relationship with respect to the end of the coupler sleeve and the area of thread engagement with the bar. The grooves are of different depths, with the groove closest to the mouth of the coupler sleeve being the deepest. Also the diameter of the circular cylindrical coupler body at each end is selected so that the wall thickness at the mouth is as thin as possible. At the center of the coupler sleeve there is an enlarged portion extending axially several threads beyond the last thread of each bar joined.

Abstract: An electrical box support assembly for stud wall construction includes two channel shape struts with one being confined by and telescoping in the other. Both have a longitudinally extending V-shape groove opening toward the box or boxes to be supported thereon whereby the boxes may quickly be attached by a self tapping screw with a screw gun. The groove ensures that each box is straight and, if more than one box is mounted, both straight and aligned. While the two parts may be telescoped they are not readily separable and are sufficiently rigid so that they do not need to be preassembled. The opposite ends of the struts are each provided with planar tabs with two longitudinally spaced designed bend points at which the strut ends or tabs may selectively be field bent to form right angle flanges matching the depth of the box to be supported.

Abstract: To facilitate the casting of stronger and more precise steel reinforced concrete members and also to facilitate the formation and field joining of such members there is provided a bar splice which includes a generally cylindrical sleeve open at one end to form an axially elongated chamber to receive a steel reinforcing bar telescoped therein, and provided with internal threads at the other end whereby a threaded bar end may be secured to the other end, and when secured sealing the other end of the chamber. The threads are preferably tapered and the chamber includes inwardly extending axially spaced annular ribs. Lateral ports are provided at each end of the chamber. The wall thickness of the chamber adjacent the threaded end of the sleeve may be increased to improve tensile capabilities. The length of the chamber is most of the splice sleeve since the threaded connection occupies little axial space.

Abstract: A method of forming a low profile brazing connection utilizes the heat from an exothermic or metallothermic reaction which takes place in a vessel having a wall of a thickness and material to radiate the heat of the reaction therethrough while nonetheless containing the reaction. The conductor or conductor lug has a flat surface and the apparatus in at least two embodiments provides for pressing the vessel and thus the flat surface against the conductor and the conductor in turn against the structure to which it is brazed. The vessel and its contents may be discarded after brazing.

Abstract: The invention provides a method and means of producing weld metal for use in joining two or more aluminum containing pieces. The method includes the steps of providing a novel mixture of reactants comprising silicon, a reducing agent, a metallic compound which is exothermically reduced by the reducing agent, and a filler metal that does not react with the metallic compound. The mixture of reactants is then exothermically reacted so as to form the weld metal for joining the metallic pieces. At least about 90 percent by weight of the weld metal is produced by the silicon and the filler metal and at least about 90 percent by weight of the weld metal has a chemical composition substantially similar to that of at least one of the metallic pieces being joined.

Abstract: A machine for taper threading the end of a bar such as reinforcing bar used in concrete construction utilizes a power operated vice to clamp and feed the bar end axially into a rotary head which contains chaser tooling holders which open uniformly on the bar end as the head rotates. The rotary head is axially stationary but contains an axially movable key or linear cam which engages a readily removable transversely extending control rod assembly in turn moving the chaser holders. Axial movement of the power vice and thus the bar end at a controlled axial speed with respect to the rotary speed of the head moves the key to cause the movement of the chaser holders. The chaser holders in addition to supporting the thread cutting chasers also support ahead of the chaser an indexable triangular insert to pre-cone the bar end.

Abstract: A track circuit retainer clip adapted to be driven on the edge of the base of a rail holds one or a plurality of conductors parallel to and within the rail base edge. The clip comprises a U-shape spring metal clip having a bight portion and upper and lower legs which embrace the rail base edge. The upper leg includes a center spring finger extending from the bight portion which includes two concave side-by-side recesses to hold the conductors against the upper leg. The outer end of the spring finger flares upwardly to facilitate insertion and the lateral edges of the spring finger are bent upwardly to avoid biting into the conductors. The lower leg includes barbs struck from the edge which terminate in truncated biting edges extending substantially parallel to the rail base edge. The line contact transverse the direction of insertion provides ease of insertion and better gripping or holding action without scratching or notching the bottom of the rail.

Abstract: A welding apparatus and method characterized by an electrically activated high temperature igniter with a pair of lead wires adapted to be connected to a high energy source of current and a high resistance bridge between the leads. The bridge is coated with an ignition material comprising a mixture of fine aluminum, one or more metal oxides or oxygen containing compounds and a binder. The welding apparatus has a vessel filled with exothermic material. When the lead wires are supplied with a high energy electrical current, the lead wires cause the ignition material to ignite in turn causing the exothermic material to ignite. If the coated bridge wire is positioned above the exothermic material, the igniter will broadcast multiple points of ignition over the top of the exothermic material.

Abstract: A wiring clip for stud frame dry wall construction holds various forms of wiring a required distance from the nearest edge or face of the stud to which the dry wall is secured. A wire form of the clip is particularly suitable for wood studs while strap forms may be used with studs made of metal or wood or other material. Each form of the invention includes an L-shape portion adapted to be secured to the face and/or side of the stud. Extending from such L-shape portion parallel to and recessed from the edge of the stud (interior of the wall board) is a strut and arm with the arm being hinged at the end of the strut remote from the L-shape portion and adapted to be folded back to extend parallel to the strut and locked in place to embrace wiring between such arm and strut. Each form of the clip is easy to install and accommodates a variety of types of wiring. The clips may be crimped by pliers tightly to embrace and conform to the wiring after installation.

Abstract: A track circuit retainer clip for a running rail adapted to secure a conductor extending perpendicular to the rail around the edge of the base of the rail in close proximity therewith. The clip includes a U-shape spring metal body having upper and lower legs adapted to embrace the edge of the base of the rail. Each leg includes a center section bowed outwardly adapted to embrace the conductor and hold it tightly against the top and bottom of the rail base edge. The legs of the clip include inwardly directed tangs or barbs struck from the edge of the legs, the inwardly projecting tip of each tang being truncated to provide a linear biting edge to engage the top and bottom of the rail base with a line contact extending longitudinally of the rail or normal to the direction of insertion of the clip.

Abstract: A position coupler for connecting reinforcing bar in concrete construction where neither bar is able to rotate either conveniently or not at all includes a sleeve at least a portion of which is internally cylindrically threaded and which receives at least one split collar insert. The insert has external cylindrical threads which match the internal cylindrical threads of the sleeve and also has internal tapered threads which match the tapered external threads on the bars to be joined. The inserts, in addition to being longitudinally split are provided with either a transverse slot or a hex head on their outer ends to receive a wrench. When a transverse slot is provided a spanner wrench may be inserted between the bar and sleeve. The tightening of the insert creates a wedge action which hoop stresses the sleeve locking the parts together and reduces slippage. The insert may be locked anywhere along the interior of the cylindrical thread portion of the sleeve to connect bars at different axial spacings.

Abstract: Surge arrestor assemblies for railroad and like circuits utilize a high surface area to cross-sectional area, broadband equal potential grounding plane which is in the form of a loop. Surges are electrically coupled to the broadband equipotential grounding plane through surge arrestors. The assembly ensures that each arrestor "see's" the same impedance so that the voltage seen at the equipment is controlled. The grounding member is supported in recesses in mounting blocks which maintain its planar condition, and which also facilitate the connections to ground, lines, arresters and equipment.

Abstract: An electrical fixture for mounting a cover plate over a wall opening which eliminates the necessity of installing an outlet box within such wall opening to facilitate the mounting of the cover plate. In a preferred embodiment the fixture comprises a rectangular plate having a front and rear surface, and a major opening and a pair of screw openings extending therethrough. Extending from the longer side edges of the major opening essentially perpendicular to the front and rear surfaces are a pair of flanges which serve to provide lateral support for the fixture within the wall opening. Extending from the center of the narrower top and bottom edges of the major opening are a pair of diametrically opposed deformable fingers which, upon insertion of the fixture within a wall opening, may be bent firmly to secure the fixture within the opening.

Abstract: A composite suitable for use as dental composite is provided by a glass material having a softening range of at least 10.degree. C. and having a particle size of less than 250 mesh to provide a precursor mix. The precursor mix is mixed with a fugitive pore forming material and a binder to form a pressable mix. The pressable mix is pressed at a pressure in excess of 5,000 pounds per square inch to form a sinterable mix. The sinterable mix is sintered for a period of time sufficient to remove said fugitive pore forming material and to form a sintered mass for crushing to form particles of less than 250 micrometers in size to be incorporated into a dental composite.

Abstract: This invention relates generally as indicated to ground rods, and more particularly to one piece ground rods of substantial length, and a method and apparatus for forming and placing such rods. Ground rods are normally steel rods having a copper cladding.

Abstract: An improved thermite reaction containment vessel and method of using the same includes a filter assembly which serves to filter the gases evolving from the thermite reaction and reduce the amount of smoke, fume and the like by-products emitted. In one preferred embodiment the filter assembly comprises a primary filter and a secondary filter. An air gap may be provided between the primary and secondary filter so as to provide additional cooling of the gases before they enter the secondary filter. The invention further provides a remote electrical ignition system which is capable of igniting thermite reaction materials without the use of a starting material. The ignition system may include an ignition fuse having an aluminum core and an outer coating comprising palladium and ruthenium or hot wire.

Abstract: Exothermic reaction mixtures are economically ignited remotely and electrically without the use of a low ignition starting material by creating a predetermined spark gap within a matrix of such mixture and then impressing a high energy spark across the gap through the use of a capacitor discharge circuit. The mixture is contained in a graphite or ceramic vessel or crucible and is supported over a tap hole or runner by a fusible metal disk. The material of the vessel is preferably graphite which is electrically conductive. In one form of the invention, an insulated wire with a bare tip is positioned just below the top surface of the mixture and the tip spaced a predetermined distance from the wall of the vessel. The capacitor discharge circuit is then employed to fire a high energy spark through a matrix of the material across the gap formed between the wire and vessel to initiate the reaction. In another form the spark gap may be established in a small cylindrical cartridge containing the material.

Abstract: An improved thermite reaction containment vessel and method of using the same includes a crucible in which the exothermic material is contained and which is connected at its lower end via a tap hole to a weld chamber in which the parts to be welded are positioned. On top of the crucible is positioned a baffle assembly which includes a plurality of expansion chambers which allows the escaping gas to expand and be reduced in velocity. As the gases move from one expansion chamber to the next the gases change direction. The expansion, direction change and the large surface area of the baffle assembly allows the gases to slow and cool before being exhausted leaving behind molten metal spatter or flame and greatly reducing the amount of smoke exhausted since particulate matter is accumulated on the baffle interior surface. Several forms of baffle assembly are disclosed using inverted stacked metal cups.

Abstract: A self-contained and sealed package of exothermic welding material includes a cup-shape disposable ceramic container for such material which is closed at the top with a heat consumable cap. The bottom of the container includes a tap hole, the lower end of which is also closed with a formed cup-shape heat consumable disk. An insulated wire pair extends along an axial groove in the exterior of the container and through a radial groove through the lip of the cup beneath the cap. The end of the wire pair within the container has the insulation removed to form a spark gap which end extends at an angle away from the interior of the container and is embedded in the exothermic material. The ends of the wire pair outside the container have the insulation removed to a greater extent so that the wires can readily be bent and connected to power unit for generating a high energy spark at the gap.

Abstract: A machine and process for forming a high strength precision bar joint and more particularly for forming rolled tapered threads on a bar end such as the tapered end of a reinforcing bar used in concrete construction. Such machine and process employs opposed oppositely rotating die disks which have conical opposed die surfaces. A thread form die is provided on the conical die surfaces in the form of thread form spirals which bear against the opposite sides of the tapered bar surface as the die disks rotate. The die surfaces include opposed recesses into which the bar end is inserted. The bar may be held for rotation against a stop as the die disks oppositely rotate. Alternatively the bar end may be held against rotation and the die disks orbited around the bar end as the die disks oppositely rotate. A tapered surface is formed on the bar end prior to roll forming of such threads as by hot or cold forging or by cutting.