Abstract: A process for preparing 1-chloro-1,1-difluoroethane and/or 1,1,1-trifluoroethane by fluorination of 1,1,1-trichloroethane with anhydrous hydrofluoric acid in the presence of antimony pentachloride in a halogenated hydrocarbon solvent which is capable of dissolving both the catalyst and 1,1,1-trichloroethane, is substantially inert in the reaction system and which has a boiling point of above 0.degree. C and a melting point of below 60.degree. C. By varying the mole ratio of hydrofluoric acid to 1,1,1-trichloroethane both fed together into a solution of the catalyst in the solvent, 1-chloro-1,1-difluoroethane and 1,1,1-trifluoroethane are obtained with a variety of desired ratios.

Abstract: Alpha type calcium sulfate hemihydrate gypsum is obtained by suspending gypsum in an aqueous solution containing a specific monocarboxylate in a specific concentration and heating the resultant suspension in a specific temperature range under atmospheric pressure. The production of this alpha type calcium sulfate hemihydrate is accomplished at an increased rate by adding a specific monocarboxylic acid to the aqueous solution, suspending gypsum in the resultant solution and heating the resultant suspension in a specific temperature range under atmospheric pressure.

Abstract: Light-transmitting compositions containing (1) 50-99% by weight of polyvinylidene fluoride or a vinylidene fluoride copolymer and (2) 1-50% by weight of a copolymer of a vinyl fluoride monomer and at least one acrylate monomer selected from the group consisting of alkyl acrylates and alkyl methacrylates wherein the alkyl group contains from one to four carbon atoms.

Abstract: A warning device for tire pressure anomalies in which the valve of the tire to be monitored is connected to a pressure variation sensor which has two pressure thresholds, one for insufficient pressure, the other for excess pressure. When one of the thresholds is reached, the sensor closes an alarm circuit connected to an electronic signalling circuit on a printed circuit fixed on a sealed casing that is rigidly connected to the frame of the wheel and which contains two batteries that supply the signal transmission circuit. The data delivered by the signalling circuit is sensed by a detector that supplies a series of frequency selectors that discriminate the tire for which a warning is given for excess or low pressure. In the case of a pressure anomaly, the frequency severally command a relay that energizes a signal light and triggers an acoustic signal.

Abstract: Apparatus for measuring the radial dimensions of a cylindrical tube by ultrasonics by means of which it is possible to measure the radial dimensions of said tube in directions perpendicular to the direction of the ultrasonic beam or beams emitted by one or more transducers, comprising a fixed ultrasonic transducer, whose emitting part is shaped like a cylindrical ring emitting ultrasonic pulses in accordance with a bundle of rays substantially parallel to the generating lines of the cylindrical tube, a truncated cone-shaped mirror whose apex angle is equal to 90.degree. and whose axis is parallel to the radii of the bundle of ultrasonic rays emitted by the transducer or transducers, a rotary shield having at least one opening arranged between the transducer and the tube whose radial dimensions are to be measured and means for collecting the ultrasonic echo returned by the tube and for measuring the time gaps separating the reception of said echos.

Abstract: A device for connecting successive duct sections, especially between a sea-bed petroleum storage tank and a surface platform, comprising a flexible tubular joint secured at both ends to two cylindrical coupling units slidably mounted respectively within two duct sections to be coupled together, remotely operated means for anchoring each coupling unit within an end-shoe and remotely operated means for forming a tight seal between the external surface of the coupling units and the internal surface of the duct sections.

Abstract: A fiber bundle is first formed of entangled fibers by passing fibers through the tapered mole of an extruder, and then the fiber bundle is provided with at least one longitudinal groove which provides an air passage in the final product communication between the ink reservoir and the atmosphere. Subsequently, one end of the fiber bundle with the longitudinal groove is dipped into a liquid urethane prepolymer to form a nib portion by impregnating the dipped portion with the prepolymer. After removal from the liquid prepolymer it is left to stand. During this standing or setting period the reactions among the constituents of the prepolymer and the volatilization of solvent produce a set urethane nib portion having capillary passages therein, and an air passageway where the groove was formed. The fiber bundle thus produced which is called "core portion" of the pen, is machined at its impregnated end to form a nib. Thus, the product consists of a nib material portion and an ink reservoir integral therewith.

Abstract: In a process for the thermal cracking of a heavy hydrocarbon in a cylindrical reactor, a portion of the content material in the reactor is taken out and injected back into the reactor according to a specific procedure to form a "wet wall" or liquid curtain on the inner peripheral wall of the reactor, thereby preventing coking in the reactor.

Abstract: Friction shoes are placed end-to-end to define a closed shape around a sector on a disc-type matrix and located in a groove cut into a support having two groove walls that cooperate to define the groove therebetween. Each of the friction shoes is biased toward one of the groove walls by a springy plate to effect a seal contact with the one groove wall. A bellows is located on a housing enclosing the matrix and the support.

Abstract: Method of making slabs of building material which can be used in place of slabs of compact marble are prepared by lining at least one surface of a mold with bonding material, introducing into the mold pieces of solid material to form an aggregate of individual pieces of said solid material with interstices therebetween, filling these interstices with bonding material which chemically bonds to the bonding material utilized for lining, allowing the bonding material to cure and harden to form a solid block of lined material, removing the solid block of lined material from the mold and slicing said block to desired size.

Abstract: A working vehicle, for example, a lawn mower, floor brush, or snowblower, is disclosed wherein a steerable ground-engaging wheel is located within the sweep of a rotary mechanism. A spindle portion of the wheel is journaled in a sleeve portion of the rotating mechanism and the mechanism is operatively connected to a power source by a power transfer system. The wheel and the rotary mechanism are independently rotatable. Apparatus is provided in both the single cutter and multiple cutter embodiments to adjust the height of the rotary mechanism as a unit. An alternate drive mechanism is disclosed for use with such devices in which a ground-engaging wheel interior of the rotating mechanism is individually powered. In another embodiment, the wheel is castered. Each of the rotating mechanisms includes a rotatable member rotatably supported within a receiving portion of a body which includes a plurality of support wheels.

Abstract: In an optical analysis system, six interference filters are mounted on a wheel on a cylindrical locus. The wheel rotates to move the filters in sequence through a beam of light and to vary the angle of incidence of the light to the filters as the filters move through the beam of light so that the wavelength passed by the filters is swept through a range of values. The intensity of light reflected from or transmitted through a test sample is detected to provide an indication of the reflective or transmissive optical density of the test sample at specific wavelengths. The angular position of each of the filters on the wheel is adjustable to make the range of light wavelengths transmitted by each filter adjustable.

Abstract: Two cylindrical shells having different diameters and covered with a metallic heat-insulation are disposed respectively within the lower and upper portions of a pressure vessel, the upper shell being closed by a lid. A chamber filled with fluid in liquid phase up to the liquid-vapor interface and with gas above said level is formed by the shells between the vaporizable fluid and the internal vessel wall, a cold liquid seal being formed by the overlapping portion of the shells. Radial expansion of the shells is permitted by supporting means at the level of at least three through-passages and is absorbed by leak-tight means placed opposite to the through-passages.

Abstract: A framework assembly for furniture in which two or more leg units are connected in a spaced relationship in a manner to permit relative movement between the leg units to accommodate irregularities in the floor on which the assembly is mounted. The top, or seat, portion of the furniture piece is supported relative to the assembly in a manner to accommodate said relative movement.

Abstract: A cylindrical shell or so-called reactor core basket is fitted with a coaxial and cylindrical bearing ring which is joined to a top flange of the core basket by means of radial struts and rests on an internal annular shoulder of the reactor vessel. Passageways between the bearing ring and the struts accommodate instruments for nondestructive testing of welded joints, the instruments being guided and displaced over the external face of the core basket in order to inspect the internal face of the reactor vessel without any need to remove reactor internals.

Abstract: A driving system for miniature dictating apparatus with winding drive means comprises a rewinding means and a forward winding means for receiving tape windings, and a motor, the shaft of which is arranged in a plane substantially perpendicular to the shafts of the rewinding and forward winding means. The driving system also includes an intermediate shaft which is driven by the motor and is positioned parallel to the rewinding shaft and the forward winding. The intermediate shaft is mounted to be parallel displaceable and is adapted to be set in at least one forward running position and a rewind position. In the forward running position only the shaft of the forward winding means and in the rewind position only the shaft of the rewinding means are adapted to be driven by means of the intermediate shaft.

Abstract: An input device for providing signals for controlling a knitting machine. The device includes a mechanical information storage means and a switch means responsive to the contents of the storage means to provide a signal corresponding to the stored information. The storage means is disposed for operation either manually by a machine operator or electromechanically in response to instructions provided by other components of the machine. The device is incorporated in a program reading apparatus to specify feeding direction of the program carrier on the knitting machine.

Abstract: A method and apparatus for providing patterning instructions in a knitting machine by reading a program carrier and converting the readings to digital signals to be stored in a memory means. A manually operable member cooperating with the reading means allows the instructions to be recalled from memory to be selectively determined for controlling for the knitting operation.

Abstract: An improved method for determining the liquid level in a petroleum thermal cracking reactor by injecting oil into the reactor at a predetermined rate not less than 5 cm/sec and measuring the liquid pressure at the point of injection and calculating the liquid level from the measured pressure.

Abstract: A separator assembly for transfer mechanisms particularly of the type used in the handling and transfer of non-ambulatory hospital patients and including an endless belt trained about a thin, flexible separator plate, a retainer bar adjustably positioned along the rear edge of the separator plate and a drive roller supported by the retainer bar on the edge thereof opposite from the separator plate. An organization of camming bars extend between the retainer bar and the rear edge of the separator plate to adjust the distance between the retainer bar and the separator plate thus to regulate the tension of the belt trained about the drive roller, retainer bar and separator plate. The camming bars may be operated either to adjust the distance between the drive roller and the front edge separator plate in parallel relationship or in canted relationship for belt tracking purposes.