Abstract: A multi-slice method of NMR imaging wherein a number of discrete slices S.sub.1, S.sub.2, S.sub.3, S.sub.4 are excited simultaneously by using the usual field gradient Gz but an r.f. pulse B.sub.1 which is a mix of a number of pulses of different discrete frequencies, f.sub.1, f.sub.2, f.sub.3, f.sub.4, and recovering data in the presence of an alternating gradient G.sub.2 z in the same direction as used to establish the slices such that discrete spin echo signals of different frequency occur for each slice. Apparatus for use in the method is also disclosed.

Abstract: A flexible test assembly is disclosed for use in nondestructive testing of ferrous objects of a variety of cross-sections. Spaced test heads are fixed to a non-magnetic, flexible band member. Each test head includes a body which houses a test probe. The flexible band member is connected to a clevis assembly through a spring biased double hinged connecting assembly. An urging means urges the clevis toward a workpiece surface to bring wear shoes of the test heads into engagement and tension the flexible test assembly into conformity with the surface of the workpiece.

Abstract: An improved power cable for a heating system that utilizes the skin effect of alternating current, and a method and apparatus for joining lengths of the improved cable. In one embodiment, the cable includes a stranded copper conductor (20) surrounded by a semiconductive layer (22) formed by carbonized tetrafluoroethylene (TFE) tape which is surrounded by a primary insulation layer (24) formed by pressure extruded, perfluoroalkoxy resin (PFA), the thickness of which is determined by an equation that considers the eccentric positioning the power cable in a heat tube (14). In a second embodiment, the cable comprises a central conductor (30) surrounded by a semiconductive layer (32), followed by a primary insulation layer (34) formed by pressure extruded PFA. A shield layer (36) formed by a layer of semiconductor material (38) and several helically wrapped drain wires (40) surrounds the primary insulation layer. A protective PFA jacket (42) is pressure extruded over the shield layer.

Abstract: An apparatus for holding x-ray cassettes and grids in which any grid of a specific length and width can be combined with any cassette of a corresponding length and width without regard to the cassette thickness. The apparatus includes a frame assembly having side rails with flanges and a back rail with flanges which form two channels, one for the grid and one for the cassette. The cassette channel is dimensioned to accept any thickness of cassette. Parabolic springs are located within side rail cassette channel portions to bias the cassette against selected flanges. Locater members are also provided to properly align the grid and the cassette.

Abstract: An x-ray tube voltage generator with automatic stabilization circuitry is disclosed. The generator includes a source of pulsating direct current voltage such as from a rectified 3 phase transformer. This pulsating voltage is supplied to the cathode and anode of an x-ray tube and forms an accelerating potential for electrons within that tube. The accelerating potential is stabilized with a feedback signal which is provided by a feedback network. The network includes an error signal generator which compares an instantaneous accelerating potential with a preferred reference accelerating potential and generates an error function. This error function is transmitted to a control tube grid which in turn causes the voltage difference between x-ray tube cathode and anode to stabilize and thereby reduce the error function. In this way stabilized accelerating potentials are realized and uniform x-ray energy distributions produced.

Abstract: A barrel loading and unloading station that includes a barrel support stand 10 for supporting a plating barrel 18 in predetermined positions and a door handling apparatus 14 for releasing and separating a barrel access door 16 from the plating barrel. The door handling apparatus 14 includes a door assembly 40 mounted for reciprocating motion towards and away from the plating barrel by a pair of trackways 42 that are mounted to an elevator mechanism 44 that is operative to raise and lower the trackways to increase accessibility to the barrel after the access door has been removed. One embodiment of the door handling assembly 40 includes a pair of rotatable spindles 56 operative to engage and rotate locking knobs 220 on the barrel access door 16 and a slide mechanism 120 for unlatching the door from the barrel. Another embodiment of the door handling assembly 40' includes a plurality of clamp engaging spreader arms 366 operative to spread and release resilient clamps 352 from the plating barrel.

Abstract: A metal finishing barrel having a body section 10 extending between a pair of end caps 12, that includes a sidewall comprising a plurality of wall sections 14, 16 joined edge-to-edge. In one embodiment, the wall sections are formed from a single, continuous sheet member 44, bent along lines of weakness in the form of V-shaped notches 46 that each define a relatively thin, hinge-like bridging section 46a that connects adjacent wall sections. External locking ribs 50 coengage edge portions of adjacent wall sections to maintain the sheet member in its assembled configuration. Alternately, individual wall panels 14', 16' are fabricated with beveled edge surfaces 46' and are secured in edge confronting engagement by the external locking ribs. In an alternate embodiment, an internal locking rib is employed that also serves as a tumbling rib and coengages locking grooves formed on inside surfaces of edge portions of each wall section.

Abstract: Coupling structure to connect sections of a compound drill stem. The drill stem has concentric passages, one connected to a fluid source to provide fluid in an area being drilled and another connected to a vacuum source to carry off the fluid and accompanying cuttings from the drilling area. In the preferred embodiment, the coupling structure includes a housing with a prismatic surface that telescopically cooperates with a similarly shaped surface of at least one of the drill stem sections to effectively transmit torque through the compound stem.

Abstract: Improved apparatus and method for performing flash welding is disclosed. The apparatus moves adjacent surfaces of workpieces toward each other and applies electrical energy between them for flash heating the surfaces in a flashing step, after which it forces the surfaces together in an upsetting step, while continuing the application of the electrical energy for a predetermined time. Apparatus is provided for calculating and monitoring the amount of electrical energy applied to the workpieces during welding, along with control circuitry, for limiting the amount of electrical energy applied during the upset step to a predetermined function of that applied during the flashing step. An energy recorder produces an indication of the amount of electrical energy applied to the workpieces during welding.

Abstract: A self-unloading centrifuge for use in a metal finishing process which comprises a drum 10 having a perforate cylindrical sidewall 10a, supported for rotation about a vertical axis by a support base 19 and a driving arrangement 12 for rotating the drum. A tilt mechanism 36 is operative to engage and rotate the drum about a substantially transverse axis, spaced laterally from the center axis of the drum in order to discharge the processed parts. Clamping devices 30 are operative to decouple the drum from its driving arrangement prior to unloading and are operative to recouple the drum after reloading. Top and side covers 140, 120, 122, 126 enclose the drum when in its operating position and open as the drum moves to its unloading and/or loading position.

Abstract: A material dispensing apparatus including drive structure for driving a feeder bowl is disclosed. A control circuit for controlling the drive includes a Hall effect amplitude sensing transducer for monitoring the magnitude of bowl vibrations and a braking circuit for controlling the damping of vibratory motion after the requisite amount of material has been fed from the feeder bowl. The braking circuit selectively reverses the current flow through a drive coil which comprises a portion of the drive circuitry of the apparatus. This current reversal disrupts the rhythm of forced oscillations which feed material from the bowl and causes bowl motion to be damped. A mechanical brake coupled to the bowl complements the braking action of braking circuit and locks the bowl in place to prevent accidental dispensing of parts.

Abstract: An electronic artificial larynx supported and operated without the use of an operator's hands. The artificial larynx includes an electrical circuit having a signal generator and a tone generator. The tone generator is attached to and supported by a pair of eyeglasses worn by the operator. A switch for opening and closing the electrical circuit is attached to a portion of the operator's body and is actuated by movement of one of the operator's limbs relative to his torso. In a preferred embodiment, the switch is attached to an arm band and is actuated by movement of an operator's arm toward his torso.

Abstract: A hot blast stove for preheating combustion air for an associated blast furnace, having a continuous, substantially cylindrical shaped peripheral wall extending from a base to a domed cover. The peripheral wall includes a first cylindrical portion defined by a refractory ring wall of a predetermined thickness, surrounded by insulation, and enclosed by a continuous metal shell; and, a second, diametrically larger, cylindrical portion disposed above the first cylindrical portion, defined by a continuation of the refractory ring wall of the first portion, surrounded by a predetermined thickness of insulating brick and insulation. The second portion is enclosed by a continuous metal shell which joins the domed cover. An annular interconnecting portion joins the cylindrical portions and includes a metal shell that diverges outwardly from the metal shell of the first portion to obliquely join the metal shell of the cylindrical portion.

Abstract: A snap action switch has a Q-shaped blade having two spring arms terminating in outwardly projecting parallel end portions which are located in a slot in a contact element, these end portions being drawn together upon insertion into the slot, and thereby stressing the blade for snap action. The end portions are retained in the slot by the reaction forces due to the stressing of the blade, and made good electrical contact with the contact element. The blade end portions may be drawn together by a clip to which a contact is rivetted.The contact element may alternatively be carried by a conductive arm separate from the blade and operable by the latter.

Abstract: A television system and method are disclosed for monitoring and indicating changes in a scene from which electromagnetic radiation, such as visible light, emanates. A television system including a television camera scans the scene in known raster fashion in a series of image frames, producing an amplitude modulated video signal describing the energy intensity distribution of the scene. Clocking and gating circuitry triggered in synchronism with television camera synchronization signals defines a set of predetermined discrete spaced locations of the raster during each image frame and samples video signal amplitude at each of the defined locations. The same discrete locations are sampled during each frame. Video selection circuitry, during a succession of sampling periods, inputs in real time a representation of each video amplitude sample to one of several storage channels of a multi-channel memory system including a multi-channel counter.

Abstract: A heat exchanger comprising an elongated tubular cylindrical member having fluid ingress and egress openings adjacent to its opposite ends and external flanges at opposite ends one of which flanges has a counterbore facing in the direction away from the cylindrical member. A plurality of graphite tubes within the cylindrical member having their opposite ends connected to graphite headers one of which is connected through a graphite end member to one end of the cylindrical member and the other of which has an outside diameter slightly less than the inside diameter of the cylindrical member and within which it is slidable or floats. The floating header has an external circumferential groove with outwardly inclined ends. A seal is provided at the end of the cylindrical member at which the floating header is located which seal includes packing in the counterbore in the adjacent flange and a gland member slidable on the floating header and adjustable towards the flange.

Abstract: A shower head assembly having a flow regulator for maintaining a flow rate through the shower head within preset limits, substantially independent of variations in supply pressure and operating temperature. The flow regulator includes a flow controller element disposed in a regulating chamber, biased in one direction by a metallic spring and urged in the opposite direction by supply pressure. The controller element cooperates with an outlet passage in the regulating chamber to form a variable orifice, reducing the effective area of the outlet in response to increased supply pressure. A retainer screen keeps the flow controller and biasing spring in place while serving as a protective filter.

Abstract: A flow control valve for controlling liquid flow, for example, water flow in a vehicle heating circuit, has a ceramic obturator plate which slides sealingly relative to a fixed sealing plate, the two plates having openings the degree of overlap of which determines the valve throughflow. A bowed leafspring maintains the slidable obturator plate in sealing contact with a mating face of the sealing plate.

Abstract: A tool for use in the removing of annular seals surrounding a shaft extending from a mechanism. The tool attaches to the mechanism and serves as a guide for a drill used to drill into the seal. The tool includes a portion which engages the end of the extending shaft, peripherally spaced longitudinal drill guide holes and a means locking the tool to the shaft.

Abstract: An ultrasonic flaw detector for detecting irregularities in an object, such as a pipe, having a segment of annular cross-section. The detector includes a transducer with an involute transmitting surface for sending ultrasonic signals into the object at equal non-radial angles of incidence. The detector further includes transmission apparatus for maintaining a constant physical relationship between the transducer and the pipe and interpretive apparatus for correlating reflections of ultrasonic signals within the object with irregularities.