Abstract: The present apparatus, method and seals relate to an external tester for defining a sealed chamber around a pipe joint, such chamber then being filled with fluid under very high pressure. After introduction of fluid into the test chamber is terminated, a determination is made as to whether or not the pressure is reducing --any such reduction indicating that a leak is present in the pipe joint. To define a test chamber which is perfectly sealed so that fluid will not escape otherwise than through a leak in the pipe joint, there are provided longitudinal sealing elements and arcuate seal segments of special construction. The longitudinal and arcuate sealing elements interrelate with each other and with extrusion-prevention and index elements in such manner that no cracks remain through which the fluid may escape.

Abstract: According to the present apparatus and method, a silent chain having an inversely-bent internal portion is caused to be in direct pressure engagement with the external cylindrical surface of a drill pipe or other object to be spun. The chain is mounted on at least five sprocket wheels, one of which is a drive wheel adapted to rotate about a movable axis which may be locked in any desired adjusted position. The pressure between chain and pipe is caused to be sufficient to spin the pipe but insufficient to injure the pipe or prevent relative sliding movement when the joint is completed. A spring is provided to absorb shock on completion of the joint, and to cooperate with the relative sliding movement in preventing injury to the apparatus or to any user thereof. The chain is caused to encompass a very large section of the diameter of the pipe, regardless of variations in pipe diameter.

Abstract: To protect sprinkler system risers and supply pipes from accidental or vandalistic damage, in an extremely simple and economical manner, a fork-shaped element is pounded down in straddling relationship around each riser and the associated pipe joint. The legs of the fork are thus on opposite sides of the riser and joint, whereas the hollow body of the fork element encompasses and restrains the riser. The fork element may be economically manufactured from a single sheet of metal, with a tubular body and diametrically-opposed parallel legs adapted to straddle the joint in the horizontal supply pipe.

Abstract: A joint-taping tool for wallboard (drywall), wherein there is almost no possibility that the cable will break after the piston reaches the top of its stroke, and wherein the operator is immediately and unquestionably informed when adhesive flow ceases. Furthermore, mechanism is provided by which--with minimized action on the part of the operator--the rollers are prevented from spinning and "throwing" adhesive (cement) during filling of the barrel.The tool will not only apply tape and adhesive simultaneously, but is rapidly convertible to deposit adhesive over previously-applied tape. This same conversion spacing option makes it possible to eliminate tape jams quickly and easily. In addition, means are provided for thoroughly cleaning the tool at the end of each day.

Abstract: The grease hood has a small dimension in the front-to-rear direction, and encloses a relatively large vortex the maximum vertical dimension of which is about equal to or greater than the maximum horizontal dimension thereof. The maximum diametral dimension of the vortex in a direction generally perpendicular to the grease-filter means is about equal to or less than the maximum diametral vortex dimension in a direction generally parallel thereto. In one illustrated embodiment, the vortex is generally circular, whereas in a second illustrated embodiment the vortex is generally elliptical and vertically elongated.The grease-filter means in one illustrated embodiment is not planar but instead is curved, the curvature cooperating with the curvature of the vortex liner to permit achievement of benefits including relatively small size of the grease hood. More specifically, the curved filter is associated with the vortex liner of generally circular shape in such one embodiment.

Abstract: A "silk screen" is provided with a patterned pervious portion the dimension of which, in the direction of screen movement, is substantially less than the circumference of the cylindrical substrate. The screen is then moved beneath a squeegee through a distance which is greater than the indicated dimension of the pattern but less than the substrate circumference, the result being that a thick film of resistive material is metered onto the substrate without any overlapping or smearing. The squeegee, at the end of the screen-printing stroke, is located at an impervious portion of the screen, so that even unspindled small-diameter ceramic substrates are disengaged from the screen with no sticking or smearing. Such cylindrical substrates are solid in order to be economical, and to permit zero moisture intrusion. It is a feature of the invention that such economical solid substrates can be used, and are driven solely by screen friction so that loading, unloading and other problems are minimized.

Abstract: A grease hood and plenum apparatus is mounted at the ceiling of a restaurant kitchen, and incorporates grease filters and also means to direct make-up air toward such filters. The make-up air passes through a capture chamber the bottom of which is open for reception of fumes from a cooking appliance disposed in the kitchen. An extended exhaust plenum chamber projects upwardly from the hood to draw air and fumes through the filters, and a supply means extends upwardly from the hood to supply make-up air thereto. Blower means deliver make-up air to the supply means and also draw air and fumes from the extended exhaust plenum. The kitchen ceiling has an opening or hole sized and shaped to receive downwardly the grease hood in premanufactured condition, and means are provided to support the grease hood at the opening and at least partially below the level of the ceiling so that fumes may pass upwardly into the capture chamber.

Abstract: The present electromagnetic pickup and method, and the piano incorporating the pickup, make use of a protuberant magnetic pole piece portion which is so constructed and related that (a) the lines of magnetic force loop back therefrom, and (b) the concentration of such lines is sharply more dense on one side of such portion than on the other side thereof (the magnetic field adjacent such portion being therefore highly asymmetrical). The tine tip is caused to vibrate adjacent such portion, which produces in an associated coil a musical signal characterized by a high degree of brilliance and piano-like musicality -- without an excess of the second harmonic. The pole piece portion is preferably offset from the axis of the coil. Preferably, there are two such offset portions, spaced on opposite sides of the coil axis, and each has a peak shaped as a substantial point or edge.

Abstract: The entry or intake portion of a grease-hood system is mounted at a low elevation, far below the elevation of the head of the cook. Furthermore, such entry portion does not extend clear to the front of the cooking appliance disposed therebeneath, thus the cooking appliance protrudes outwardly from beneath the entry portion. The apparatus and method are such that the flow of fumes and air from the cooking appliance to the entry portion of the hood is substantially entirely the result of convection. There is, however, a forced flow in the hood system at a region above the entry portion, the forced flow being such that fumes and air are directed at the grease filter means. In the forced-flow portion of the system, air from outside the room is passed directly to the grease hood, and air and fumes which pass through the grease filter means are passed to a region exterior to the room and/or are recirculated back to the hood. There is a vortical flow of air and fumes in the forced-flow portion of the system.

Abstract: A pneumatically-operated thread protector for casing pipe, etc., has a thick rubber bladder which extends on (a) the outside, (b) the inside, and (c) the extreme end of the pipe, such bladder being generally U-sectioned or hairpin-sectioned. Provided around and within the bladder is a shock-resistant and wear-resistant metal housing which is also U-sectioned or hairpin-sectioned generally correspondingly to the bladder. Means are provided to seal the lips of the bladder to the housing, and to prevent the housing from shifting off the inflated bladder, in such manner as to permit substitution of new bladders yet to (a) maintain effective air seals, and (b) maintain the parts in assembled condition despite the effects of tremendous loads and shocks. Means are provided to inflate the bladder so that it will grip or grasp tightly the exterior and interior cylindrical surfaces of the pipe end, thus minimizing the possibility of accidental demounting of the protector from the pipe.

Abstract: The invention makes use of refrigerant passages or conduits in very effective heat-exchange relationship with the compression chamber and other hot parts of the compressor in a refrigeration system. The passages communicate at their inlet with an expansion valve or orifice, and at their outlet with a region of the compression chamber such that introduction of refrigerant vapor from the passages does not adversely affect the suction of the compressor. The expansion valve receives liquid refrigerant directly from the condenser of the system. The refrigerant vaporizes while passing through the passages, and then is injected in vapor form into the compression chamber for compression along with the main body of refrigerant vapor received from the evaporator of the system. Heat from the compressor, particularly the compression chamber and (in a piston-type compressor) the valve plate, is transferred through the walls of the passages to the vaporizing liquid-cooled refrigerant passing through the passages.

Abstract: The casing of an external leak tester for joints in oil well pipes is greatly reinforced in a compact manner by a cage which is symmetrical about two planes oriented at right angles to each other -- each plane containing the axis of the pipe to be tested. Four parallel pins interconnect the components of the cage, and one such pin (a lock pin) is retractable by piston means in order to permit the cage and thus the casing to open wide for lateral reception of the pipe. A plurality of means are provided to effect precise and rapid alignment of apertures in the cage, in order that the piston-operated lock pin may be inserted without binding to thereby lock the cage in closed condition. Cylinder-operated hooks are provided to effect augmented sealing compression of the sealing means for the test chamber, and to close the cage to the position at which the lock pin may be inserted as indicated above.

Abstract: A selective distortion control circuit for an electrical musical instrument employs a cathode or emitter follower valve having a load resistance that is selectively changed to provide either a clean or distorted output signal. The mutually in-phase clean input and distorted output of the valve are connected to opposite sides of a potentiometer of which the wiper provides a selectively proportioned mixture of clean and distorted signals. The relative amount of distortion may be selected, and once selected, the operator may readily choose between clean and distorted sound by changing the load resistance.

Abstract: The second wire bond is made in a semiconductor circuit simultaneously with breaking of the wire, in such manner that a "tailless" wirebond is achieved in minimum time and with no damage to either the wire or the bonding pad. The bond is made ultrasonically, and tension is applied to the wire during the actual time that ultrasonic bonding energy is supplied to the bonding tool. Such tension is applied by a spring or its equivalent, and is so predetermined that application of the bonding energy to the bonding tool will not only create the ultrasonic bond but will also break the wire.

Abstract: A greatly extended plenum chamber, comprising a plenum or exhaust chamber and a plenum extension connected thereto, is employed in combination with grease filters which operate by impingement and by centrifugal action. Furthermore, a stream of air is directed against the upstream surfaces of the filters. The result of the combination is a surprisingly effective removal of grease and smoke from cooking fumes, with consequent minimization of grease coatings on the surfaces of the plenum chamber and of the exhaust blower connected thereto. When space does not permit vertical installation of a large extended plenum chamber, portions of such chamber may be inclined from the vertical and/or may be replaced by a plurality of smaller plenum extensions.In an additional embodiment, the effect of a very large plenum extension is obtained by a single and much smaller plenum extension.

Abstract: The method comprises employing electrical contact resistance to sense whether or not there is incipient precipitation of adherent scale, paraffin wax, etc., on surfaces immersed in various liquids. The method is surprisingly sensitive, and otherwise effective, even when the liquids are electrically conductive. The method further comprises performing certain steps relative to the submerged surfaces, and/or relative to the liquids, in order to control precipitate formation. The selection of polarity, materials, etc., is caused to be such that sensitivity is maximized, and electrolytic dissolution of the submerged elements is minimized.