Patents Examined by S. Leon Bashore
  • Patent number: 4800319
    Abstract: A low-pressure mercury vapor discharge lamp having a very satisfactory color rendition, (R(a,8).gtoreq.85), a color temperature of 2300-3300 K and a color point on or near the Planckian curve. The lamp is provided with a luminescent layer comprising:a. a luminescent alkaline earth metal halophosphate activated by Sb.sup.3+ and Mn.sup.2+ having a color temperature of 2900-5000 K;b. a luminescent material activated by Eu.sup.2+ with an emission maximum van 470-500 nm and a half-value width of at most 90 nm, andc. a luminescent rare earth metal metaborate activated by Ce.sup.3+ and Mn.sup.2+, having a fundamental lattice Ln(Mg,Zn,Cd) B.sub.5 O.sub.10, in which Ln represents the elements Y, La and/or Gd, which borate has red Mn.sup.2+ emission.Further, the lamp is provided with means for absorbing blue radiation having wavelengths below 480 nm. Preferably, the luminescent layer further contains:d. a luminescent material activated by Tb.sup.3+ which exhibits green Tb.sup.3+ emission.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: January 24, 1989
    Assignee: U.S. Philips Corporation
    Inventors: Johannes T. C. Van Kemenade, Johannes T. W. De Hair, Everhardus G. Berns
  • Patent number: 4775464
    Abstract: This invention relates to a process for the dynamic separation of mixtures of materials, such as minerals having different specific gravities, by using one dense medium having two different densities, the process includes a closed loop flow system utilizing two medium streams of two different densities for separating mixtures of materials into two material/dense medium streams. The dense material is recovered from the two material/dense medium streams after separation and splitting by creating two return streams of two different densities which are individually fed to a tub, and the two medium streams are formed from the dense medium of the tubs by effecting overflow of the dense medium between the two tubs to establish substantially equal volume therebetween and maintain equal volume therebetween.
    Type: Grant
    Filed: February 10, 1986
    Date of Patent: October 4, 1988
    Assignee: Prominco s.r.l
    Inventors: Gianfranco Ferrara, Henry J. Ruff
  • Patent number: 4759826
    Abstract: An improved process for purifying thionyl chloride by the double distillation of an impure mixture of thionyl chloride, sulfuryl chloride, sulfur monochloride, sulfur dichloride and sulfur dioxide is disclosed. The double distillation process is conducted in the presence of sulfur to convert sulfur dichloride into sulfur monochloride. The sulfuryl chloride content of the mixture is reduced by contacting the vapor from the reboiler in the first stage distillation with activated carbon prior to fractional distillation in the column. The product of the first stage distillation is then redistilled to produce a thionyl chloride product of high purity.
    Type: Grant
    Filed: October 23, 1986
    Date of Patent: July 26, 1988
    Assignee: Occidental Chemical Corporation
    Inventor: Gary M. Sellers
  • Patent number: 4758309
    Abstract: A device for mounting felts in papermaking machines, which device consists of a supplementary strip mounted along the lengthwise edge or edges of the felt. Spaced apart apertures are formed in the strip along the length of the felt. The apertures are shaped so as to be gripped manually or by means of special tools. Instead of a strip with apertures formed therein separate gripping means in the form of handle loops may be attached to the felt in spaced-apart relationship along the edge or edges of the felt.
    Type: Grant
    Filed: June 20, 1985
    Date of Patent: July 19, 1988
    Assignee: Nordiskafilt AB
    Inventor: Gunnar Johansson
  • Patent number: 4758311
    Abstract: A method for passivating the surface of the strippers of the urea plants, where the temperatures are very high, where the pressures range from 120 to 240 Kg/cm.sup.2 and where the effluent process flow from the synthesis reactor undergoes one or more falling-film evaporations, preferably in countercurrent with a driving gas consisting of NH.sub.3 or CO.sub.2, characterized by the fact that the passivation is carried out by means of a sinergistic combination of oxygen, preferably injected into the bottom of at least one stripper, and of a second passivating agent, preferably injected into the process flow entering the head of at least one stripper, wherein said second passivating agent is injected in the liquid state or as a liquid solution, before or contemporaneously to the start of the evaporation.
    Type: Grant
    Filed: May 11, 1987
    Date of Patent: July 19, 1988
    Assignee: Montedison S.p.A.
    Inventors: Giorgio Pagani, Giuseppe Faita, Ubaldo Grassini
  • Patent number: 4756797
    Abstract: A multiple effect evaporator system and a process for concentrating a process liquid wherein evaporated process liquid from one effect serves as heating fluid in an adjacent effect. Low energy heating fluid in vapor form is fed to an evaporative surface condenser where it is condensed and collected as clean and foul condensate. Coolant for the evaporative surface condenser is provided in the form of process liquid from one of the effects. Prior to passage into the evaporative surface condenser, the process liquid is cooled. In the cooling circuit of the evaporative surface condenser, the process liquid absorbs the heat of condensation of the heating fluid and subsequently rejects the heat into a counter flowing air stream. The process liquid is thereafter heated and returned to another of the multiple evaporator effects.
    Type: Grant
    Filed: October 20, 1986
    Date of Patent: July 12, 1988
    Assignee: Kamyr, Inc.
    Inventors: Carl Elmore, Timothy Carter
  • Patent number: 4755260
    Abstract: A papermaker's felt having an elongated base fabric, at least one batt layer, and means to interconnect the opposite longitudinal ends of the base fabric to make an endless felt. The endless felt is made by providing seaming loops on opposite longitudinal ends of the base fabric and bringing the loops into interdigitated engagement on the papter making machine; introducing a core element into the common bight of said loops to connect them; and finally needling the batt layer so that the abutting ends thereof (which abut each other at right angles to the longitudinal direction and obliquely to the thickness direction) are engaged without any opening between them.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: July 5, 1988
    Assignee: Ichikawa Woolen Textile Co., Ltd.
    Inventor: Norio Sakuma
  • Patent number: 4755258
    Abstract: Calcium containing sulphate spent liquor is deactivated by means of heating. Spent liquor is heated by means of direct condensing in a flash-steam-system. Liquor vapors generated during expansion of the already deactivated spent liquor are used for heating the spent liquor. Spent liquor is led to a retention tank through n+1 in series connected direct condensers (DK I-DK V) and from the retention tank through n in series connected flash tanks (FT I-FT IV) disposed counter-currently to the direct condensers. In the last one of the direct condensers (DK V) the liquor is heated by means of externally supplied steam; in all others (DK I-DK IV) by means of expansion vapor.
    Type: Grant
    Filed: May 29, 1986
    Date of Patent: July 5, 1988
    Assignee: Ahlstromforetagen Svenska AB
    Inventor: Rolf Ryham
  • Patent number: 4752315
    Abstract: A nozzle or nozzles for spraying cooling water are disposed at the lower end of a slag suction path. A cooling water down-flow passage is provided on the outer periphery of an inner tube which constitutes a slag suction path. A water sump is provided below the cooling water down-flow passage, the water sump being located lower than the each nozzle. A lower end opening of the cooling water down-flow passage is disposed lower than the each nozzle and is submerged in water in the water sump. The cooling water down-flow passage, except the lower end opening, is adapted to be closed up. When the cooling water down-flow passage is closed up, water in the passage is stopped by atmospheric pressure acting upon the surface of the water in the water sump, so that it is prevented from flowing down.
    Type: Grant
    Filed: July 27, 1986
    Date of Patent: June 21, 1988
    Assignee: Kubota, Ltd.
    Inventors: Katsumi Nagasaki, Yoshihiro Inoue, Tetsuo Momose
  • Patent number: 4750975
    Abstract: Vapor and liquid contact structure for distillation, fractionation, rectification, absorption, and the refining, in a column, of various liquid materials such as petroleum, chemical, and alcohol solutions. Provision is made for the inclusion of vertically-spaced bubble plate chambers, having respective liquid/vapor contact devices, to accommodate contact of counter-current flows of reflux liquid and vapors. Downcomer means including slanted ramps, disposed outside of the vapor conduit-defining interior, define elongate downcomer structure for liquid flow and thereby, i.e., by such slanted construction, reduce froth or foam passing to a next lower contact device, eliminating unwanted counter-current gas entrainment between contact devices. Liquid flow rates over exit weirs beyond 30 gpm/inch are obtained. Downcomer reflux reservoir depth can be adjusted by an adjustable gate proximate the slot opening to a given contact device.
    Type: Grant
    Filed: March 17, 1986
    Date of Patent: June 14, 1988
    Assignee: Uni-Frac, Inc.
    Inventors: Trent J. Parker, Byron M. Parker
  • Patent number: 4751427
    Abstract: A highly efficient, AC-excited, blue light-emitting phosphor for solid-state thin-film electro-luminescent (TFEL) devices is comprised of strontium sulphide (SrS) host material doped with cerium fluoride (CeF.sub.3) acting as an emitter providing a source of photons. The blue SrS:CeF.sub.3 phosphor is about one hundred times brighter than the brightest zinc sulphide/thulium fluoride (ZnS:TmF.sub.3) blue phosphor heretofore known. To increase brightness level, at some loss of energy efficiency, electron-injection layers of zinc sulfide (ZnS) are placed on either side of the SrS:CeF.sub.3 layer in the TFEL device.
    Type: Grant
    Filed: July 16, 1986
    Date of Patent: June 14, 1988
    Assignee: Planar Systems, Inc.
    Inventors: William A. Barrow, Christopher N. King, Richard E. Coovert, Ronald O. Petersen
  • Patent number: 4750971
    Abstract: An improved method of manufacturing a semiconductor device having a narrow groove or slot is provided. There are formed on a substrate a heavily n-doped first silicon layer, and oxidation-preventing layer such as silicon nitride, and a weakly doped or undoped second silicon layer. By means of a single masking step, a part of the second silicon layer is removed to exposed portions of the oxidation preventing layer, and the remaining part is partially oxidized. A particle bombardment of the exposed portions of the oxidation-preventing layer is carried out with the oxidized part of the second silicon layer being a mask. Subsequently, the oxide on the second silicon layer is removed leaving non-exposed portions of the oxidation-preventing layer, and then the exposed portions of the oxidation-preventing layer on the first silicon layer are completely etched away.
    Type: Grant
    Filed: January 27, 1987
    Date of Patent: June 14, 1988
    Assignee: U.S. Philips Corporation
    Inventors: Henricus G. R. Maas, Johannes A. Appels
  • Patent number: 4749396
    Abstract: An improved method of forming an optical fiber preform includes separately forming a rod-like inner member and a hollow tube-like outer member by a soot glass deposition technique. The inner member is inserted into the outer member, while they are both in their unconsolidated state, and the asssembled parts heated to cause the outer member to collapse about the inner member and form a preform. The resulting preform can be drawn in one or more stages to provide an optical fiber having sharp step change in its index of refraction between the core and the cladding, a superior quality core to cladding interface, and improved optical transmission qualities. The inner and outer members can, if desired, be partially consolidated but for an unconsolidated layer at their interface prior to heating the outer member to cause it to join with the inner member.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: June 7, 1988
    Assignee: Polaroid Corporation
    Inventor: John W. Hicks, Jr.
  • Patent number: 4749473
    Abstract: Wastepaper is treated by a ink-removing process in which an aqueous wastepaper pulp slurry is introduced into a treating vessel, air is blown into the wastepaper pulp slurry preferably through a number of air-blowing orifices formed on a peripheral surface of at least one horizontal cylinder located in the bottom portion of the vessel to absorb ink particles floating in the wastepaper pulp slurry by air bubbles ejected from the orifices and rising toward the wastepaper pulp slurry surface. The resultant ink-absorbed froth is then removed. In this process, air is blown in an amount satisfying the relationship (I)G/L.gtoreq.5.0 (I)wherein L is the volume (m.sup.3) of the wastepaper pulp slurry in the treating vessel and G is the total volume (Nm.sup.3) of the air bubbles blown into the vessel, to promote the contact of the air bubbles with the ink particles in the wastepaper pulp slurry.
    Type: Grant
    Filed: July 1, 1987
    Date of Patent: June 7, 1988
    Assignee: Oji Paper Co., Ltd.
    Inventors: Akira Shioiri, Yoji Isobe, Hiroyasu Hayano
  • Patent number: 4749445
    Abstract: Disclosed in a process for producing gloss and smoothness on the surface of a paper web, comprising:A. advancing a web of papermaking fibers through a nip formed by a smooth metal finishing drum and a resilient backing roll; andB. heating the drum to a temperature at least high enough to heat a substrata portion of the web to a temperature in which gloss and smoothness rapidly increase with increasing temperature due to thermoplastic molding of the substrata beneath the surface and at a temperature higher than where substantial gloss and smoothness would have already been obtained by molding of the surface of the web.
    Type: Grant
    Filed: July 3, 1986
    Date of Patent: June 7, 1988
    Assignee: S. D. Warren Company
    Inventor: Jay H. Vreeland
  • Patent number: 4749441
    Abstract: A method of fabricating single crystal silicon in a "mushroom" shape for use in fabricating devices such as a Silicon-On-Insulator-Like MOSFET. One embodiment of the inventive method entails fabricating a hole-within-a-hole structure in a thick silicon dioxide layer disposed on a single crystal silicon substrate, growing single crystal silicon in the inner hole, etching back the silicon dioxide layer to expose a portion of the silicon in the inner hole, and growing single crystal silicon by selective epitaxial growth in the outer hole.
    Type: Grant
    Filed: December 11, 1986
    Date of Patent: June 7, 1988
    Assignee: General Motors Corporation
    Inventors: John C. Christenson, Peter J. Schubert
  • Patent number: 4749395
    Abstract: Preforms for drawing into glass fibers are relatively quickly produced by extruding filaments or tapes from polysiloxanes and/or heteropolysiloxanes and curing such filaments. A cylindrical wound body is produced from such cured filaments by winding such filaments onto an arbor. The wound body is converted, by heating in an oxidizing atmosphere, into an oxide body composed of SiO.sub.2 and, under certain conditions, containing doping amounts of select heteroelements present in the heteropolysiloxane. After removal of the arbor, a gas stream containing chlorine gas is flushed at a temperature of about 1000.degree. to 12,000.degree. C. through the oxide body to remove any traces of water and the dry oxide body is sintered into glass at a temperature of about 1200.degree.-1500.degree. C. The tubular preform thereby attained is collapsed and a glass fiber is drawn therefrom. This process is particularly suitable for the fabrication of gradient optical fibers.
    Type: Grant
    Filed: June 13, 1985
    Date of Patent: June 7, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hartmut Schneider
  • Patent number: 4749439
    Abstract: A thin film magnetic head including a first magnetic material layer, a gap material layer formed on the first magnetic material layer, an inorganic insulating layer having a generally trapezoidal shape in cross section and formed on the gap material layer, a second magnetic material layer formed on the organic insulating layer and conductor coils formed on the gap material layer within the organic insulating layer, in which the gap material layer is tapered by an etching process with the organic insulating layer of the generally trapezoidal shape in cross section used as a mask, and thereafter the organic insulating layer is etched so that the organic insulating layer is caused to stand back from the gap material layer a predetermined distance in the direction away from the air bearing surface of the head which is opposed to a recording medium.
    Type: Grant
    Filed: July 24, 1985
    Date of Patent: June 7, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuo Kobayashi, Sadanori Nagaike
  • Patent number: 4747861
    Abstract: A method for depositing glass by decomposition of glass forming compounds in the vapor phase wherein a gaseous mixture of glass forming compounds is introduced into a refractory tube, and a source of heat is applied to the tube while the tube is being rotated. The source of heat is moved parallel to the axis of the tube to provide a moving hot zone therealong and at the same time to cause a conical neck portion to develop in the tube at which deposition of the glass forming compounds takes place.
    Type: Grant
    Filed: March 14, 1984
    Date of Patent: May 31, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hartmut Schneider
  • Patent number: 4747915
    Abstract: A falling-film process and apparatus for the cocurrent evaporation of a solution is disclosed. The process utilizes a tube-bundle heat exchanger in which the upper ends of the individual tubes of the tube-bundle are closed. Apertures, preferably in the form of slots, are formed adjacent the closed-end of the individual tubes. A liquid heel is maintained above the highest of said apertures and flows into the interior of the tubes through said apertures. Upon entering the tubes the liquid and any vapor released therefrom flows cocurrently in a downward direction. The vapors released from the liquid are recycled to a point above the liquid heel through conduit means separate from the individual tubes.
    Type: Grant
    Filed: March 6, 1986
    Date of Patent: May 31, 1988
    Assignee: Montedison S.p.A.
    Inventor: Giorgio Pagani