Patents Represented by Attorney Larry R. Cassett
  • Patent number: 5419689
    Abstract: A vacuum pump which includes an oil pump for raising the pressure of oil in the vacuum pump during operation of the vacuum pump and an inlet valve for isolating the vacuum pump inlet during non-operation of the vacuum pump. The vacuum pump has an operating valve acting in an oil line between the oil pump and the inlet valve and in an oil line between the inlet valve and an oil reservoir. The operating valve is movable by means of oil pressure between a second position associated with vacuum pump operation in which the oil line between the inlet valve and the oil reservoir is closed and a first position associated with vacuum pump non-operation in which the oil line between the inlet valve and the oil reservoir is open. A means is provided to allow high pressure oil from the oil pump to communicate with the inlet valve in at least the second position.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: May 30, 1995
    Assignee: The BOC Group plc
    Inventor: Alan E. K. Holbrook
  • Patent number: 5419137
    Abstract: A process and apparatus for producing a high purity nitrogen vapor product from the rectification of air within high and low pressure columns operatively associated with one another by a condenser-reboiler. The high pressure column incorporates a sufficient number of theoretical stages to produce a high purity nitrogen vapor which after being condensed by the condenser-reboiler, serves to partially condense a lower purity nitrogen vapor tower overhead produced in the low pressure column through indirect heat exchanger. In such service, the condensed, high purity nitrogen vapor is at least partially vaporized and utilized as a product stream. Since there is no direct heat exchange with the high purity nitrogen produced within the high pressure column and the lower purity nitrogen vapor produced in the low pressure column, the low pressure column can incorporate fewer theoretical stages and therefore can be built at less expense than similar air separation plants of the prior art.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: May 30, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Paul A. Sweeney, Ramachandran Krishnamurthy
  • Patent number: 5417950
    Abstract: A gas mixture comprised of nitric oxide and, optionally an inert gas, and containing small amounts of nitrogen dioxide, and perhaps moisture and sulfur dioxide, is purified by passing the gas stream through a bed of metal cation-free alumina-deficient zeolites of types Y or ZSM-5. The concentrations of nitrogen dioxide, sulfur dioxide and moisture in the gas stream are reduced to about 1 ppm or less as the gas mixture passes through the bed of zeolite.
    Type: Grant
    Filed: July 7, 1994
    Date of Patent: May 23, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Lien-Lung Sheu, Martin Bulow
  • Patent number: 5417934
    Abstract: A gas treatment method and apparatus for use in connection with processes of etching semiconductor devices or of plasma enhanced chemical vapor deposition onto semiconductor materials. In accordance with the method and apparatus, the exhaust gases are introduced into first and second stages while heating the first and second stages. The stages can be contained within a heated cartridge. The first stage contains silicon or a silicon-rich alloy or a silicon-rich substance in a particulate form and a partial coating of copper or a copper rich substance in intimate contact with the silicon, the silicon-rich alloy or the silicon-rich substance. The second stage contains calcium oxide, a calcium oxide containing material, or a soda lime containing medium.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: May 23, 1995
    Assignee: BOC Limited
    Inventors: James R. Smith, Peter L. Timms
  • Patent number: 5417742
    Abstract: Perfluorocarbons are recovered from gas streams by subjecting the gas stream to an adsorption process in a bed of one or more energetically homogeneous adsorbents such as silicon-rich adsorbents of the FAU structure, silicon-rich adsorbents of the BEA structure, silicon-rich adsorbents of the MOR structure. The adsorption process is preferably pressure swing adsorption or temperature swing adsorption.
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: May 23, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Satish S. Tamhankar, Ramakrishnan Ramachandran, Martin Bulow, Theodore R. Galica
  • Patent number: 5416244
    Abstract: An improved process for the production of isoflurane is disclosed. Isoflurane is formed by the exhaustive chlorination of 2,2,2-trifluoroethyl difluoromethyl ether with chlorine gas. The reaction mixture, preferably without purification or refining, is treated with UV light in the presence of isopropanol to reduce 1,1-dichloro-2,2,2-trifluoroethyl difluoromethyl ether, the other major component thereof, to isoflurane. Isoflurane is thereby obtained in yields of at least 80%.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: May 16, 1995
    Assignee: Ohmeda Pharmaceutical Products Division Inc.
    Inventors: Leonid A. Rozov, Fernando Quiroz, Gerald G. Vernice
  • Patent number: 5415897
    Abstract: A method of depositing a solid substance on the surface of the substrate in which the solid substance is dissolved in a solvent to create a first solution. The solid substance is less freely divided prior to dissolution than when deposited on the substrate and the deposition density of the solid substance on the substrate is regulated at least in part by solid substance concentration. The solid substance is insoluble in a liquified gas and the first solution is soluble in the liquified gas. The solvent also is capable of depressing the freezing point of the liquified gas upon expansion of the liquified gas. The first solution is dissolved in the liquified gas to create a second solution having a sufficient concentration of the solvent relative to the liquified gas that solidification of the liquified gas is substantially prevented upon the expansion thereof. Preferably, this concentration of solvent is a minimum to prevent overuse of environmentally hazardous solvents.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: May 16, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Edward Chang, Shuen-Cheng Hwang, Paul Stratton
  • Patent number: 5411581
    Abstract: A gas separation apparatus employing a membrane gas separation unit and containing a regenerative desiccant for preventing any free water contacting the membranes within the membrane separation unit.
    Type: Grant
    Filed: January 11, 1994
    Date of Patent: May 2, 1995
    Assignee: The BOC Group plc
    Inventor: Graham B. Robinson
  • Patent number: 5409360
    Abstract: A rotary pump comprising a stator body having a bore and a rotor assembly mounted eccentrically in the bore to form a cavity between the stator body and the rotor assembly. The rotor assembly has two blades slidably positioned in diametrically opposed slots in the rotor assembly. In use of the pump the two blades are substantially in contact with an inner wall of the stator body. The stator body has an inlet and an outlet to allow, in use of the pump, fluid being pumped to enter into and be expelled from the cavity by means of the rotating vanes. The rotor assembly is of integral construction with each slot defined therein having an arcuate base and each blade has an end portion substantially conforming to the arcuate slot base.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: April 25, 1995
    Assignee: The BOC Group, plc
    Inventor: Henryk Wycliffe
  • Patent number: 5407551
    Abstract: A planar magnetron sputtering device with improved target utilization and cooling capacity is provided. The device includes a magnet yoke as the main structure of the cathode body. The magnet yoke is made of low carbon steel which provides magnetic shunt and physical strength. The target is attached to a metal backing plate so that the side surface of the target is substantially flush with the side surface of the backing plate. Suitable magnets are adapted for producing a closed-loop magnetic field over the lower surface of the target. The magnets include an outer magnet that has an annular structure positioned around an inner elongated magnet. The outer magnets are positioned along the perimeter of the backing plate and small magnets are employed to create larger active target area. The magnet yoke also comprises extension structures which are positioned along the side surface of the target. These extensions shunt the magnetic field at the edges of the target.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: April 18, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Peter A. Sieck, Milan R. Kirs, Terry A. Trumbly
  • Patent number: 5407492
    Abstract: A process for a passivated film which is far reduced in the amount of gas discharge and can desorb an adsorbed gas more readily, which process comprises heating a stainless member with a surface roughness, Rmax, of 1.0 .mu.m or less in an atmosphere of a mixture comprising oxygen gas and an inert gas and having a dew point of -95.degree. C. or below, an impurity concentration of 10 ppb or less and an oxygen content 5 ppm 25 vol % at 300.degree. to 420.degree. C.
    Type: Grant
    Filed: June 23, 1993
    Date of Patent: April 18, 1995
    Assignee: Osaka Sanso Kogyo Ltd.
    Inventors: Tadahiro Ohmi, Yoshiyuki Nakahara, Takashi Sakanaka, Eiji Ohta, Satoshi Mizokami
  • Patent number: 5402646
    Abstract: A first stream of compressed, cooled air is introduced into a higher pressure rectification column through an inlet and is separated into nitrogen vapour and oxygen-enriched liquid. At least some of the nitrogen vapor is condensed in a condenser and one stream of the resulting liquid nitrogen is used as reflux in the column and another stream as reflux in a lower pressure rectification column. Oxygen enriched liquid withdrawn from the column through an outlet is separated in the column. Impure liquid oxygen product is withdrawn from the column through an outlet. A less pure stream of liquid oxygen is withdrawn from the column through an outlet, is reboiled in a condenser-reboiler by indirect heat exchange with a second stream of air and is reintroduced into the column at its bottom through an inlet.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: April 4, 1995
    Assignee: The BOC Group plc
    Inventor: Thomas Rathbone
  • Patent number: 5401151
    Abstract: A mechanical vacuum pump is provided with a pair of cooperating rotors mounted on rotatable shafts within a pumping chamber. Each of the pair of cooperating rotors has a claw profile that terminates in a leading edge shaped to present an angle of no greater than 90 degrees relative to the wall of the pumping chamber. The leading edge shaped in such manner helps to prevent contaminant buildup on the wall of the pumping chamber.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: March 28, 1995
    Assignee: The BOC Group plc
    Inventor: Richard G. Allen
  • Patent number: 5400425
    Abstract: An illuminator for use with a variety of end use light emitting devices for administering light for therapy and/or observation of an infant. One of the end use emitting devices is a device to provide phototherapy to the infant and is prevented by the illuminator from emitting light that has not been filtered to select the desire spectrum of wavelengths for phototherapy. The illuminator prevents the introduction of a connector to the phototherapy device from being inserted to an operative, secured position unless the proper filter is in position to filter out all of the undesired wavelengths before the light radiation can reach the phototherapy end use emitting device. Other end use light emitting devices may, however, be used with the same illuminator and their connectors are readily inserted into the illuminator to receive light radiating from the illuminator to the end use light emitting device.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: March 21, 1995
    Assignee: Ohmeda Inc.
    Inventors: Howard B. Nicholas, Anthony D. Buttitta
  • Patent number: 5396772
    Abstract: A method of cryogenically separating a mixture of atmospheric gases within a distillation column system having at least one distillation column. In accordance with the method, liquid and gaseous phases of the mixture of atmospheric gases to be separated are countercurrently passed through structured packing. The column is operated with a pressure greater than 2 bars and with a vapor rate of the vapor phase that is less than a critical vapor rate at which the column floods and which varies with the liquid rate of the liquid phase. Minimum and critical vapor rates at which the column floods are set in accordance with experimentally derived data for maximum column utilization in terms of packing volume or column throughput. Additionally, separation performance in terms of HETP increases with the increase in pressure so that a lower than prior art height of structured packing can be used to obtain a particular separation.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: March 14, 1995
    Assignee: The BOC Group, Inc.
    Inventors: Kevin McKeigue, Ramachandran Krishnamurthy
  • Patent number: 5392608
    Abstract: A method and apparatus for subcooling a liquid composed of a volatile fluid, for instance, a saturated liquid cryogen, in which two chambers are filled with the fluid and are each initially pressurized after filling so that the fluid is converted to a subcooled liquid. The pressurization of the two chambers is maintained as the subcooled liquid is delivered from each of the two chambers. The filling and the delivery of the two chambers is effected in accordance with a cycle in which one chamber is filled and initially pressurized just prior to the completion of the delivery from the other chamber to allow the continual delivery of the subcooled liquid.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: February 28, 1995
    Assignee: The BOC Group, Inc.
    Inventor: Ron C. Lee
  • Patent number: 5390665
    Abstract: An anaesthetic vaporizer includes a passageway 10, 30 for directing carrier gas through a fixed laminar restrictor 32 to a vaporizing chamber 26. Liquid anaesthetic agent is injected into the vaporizing chamber 26 from a constant level tank 12 the output of which is controlled by a laminar control valve 28. Liquid anaesthetic agent flow is determined by the pressure of carrier gas in the passageway 10, 30 and the setting of the liquid laminar control valve 28.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: February 21, 1995
    Assignee: The BOC Group plc
    Inventor: Stuart C. Leach
  • Patent number: 5387122
    Abstract: The pulse oximeter probe uses an inexpensive connector to electrically interconnect the sensor elements with the pulse oximeter. One segment of the probe connector contains a set of connector pins that are wired to the sensor elements. Another segment of the probe connector is equipped with a mating configuration of sockets which align with these pins. Three projections function to automatically align the connector pins with the connector sockets. Two of the projections engage a mating aperture in the other connector segment to fasten the two connector segments together, while a third projection aligns with an edge of the other connector segment to position the two connector segments.
    Type: Grant
    Filed: May 18, 1993
    Date of Patent: February 7, 1995
    Assignee: Ohmeda Inc.
    Inventors: Daniel S. Goldberger, Timothy A. Turley, Kirk L. Weimer
  • Patent number: 5385611
    Abstract: An apparatus for forming a resin coating on the surface of an article having a three-dimensional structure, comprising: (i) a compartment (a) in which the surface of the article is coated with a resin solution, (ii) a compartment (b) in which said resin solution coated on said article is cured; and (iii) means for successively transporting said article through said compartments; wherein said compartment (b) is substantially shut off from the outside air and has an entrance and an exit for said article transport means, said entrance and said exit being provided with respect guide members having substantially the same cross-sectional configuration.
    Type: Grant
    Filed: March 4, 1993
    Date of Patent: January 31, 1995
    Assignee: Osaka Sanso Kogyo Ltd.
    Inventors: Yoshihiro Matsumoto, Mitsuhiro Shinomoto, Yasunori Yagi
  • Patent number: D355032
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: January 31, 1995
    Assignee: Ohmeda Inc.
    Inventors: Daniel S. Goldberger, Mark Hibl, James H. Taylor, Timothy A. Turley, Gregory D. Volan, Kirk L. Weimer