Patents Assigned to The BOC Group plc
  • Patent number: 5882184
    Abstract: A burner is provided with a central fuel outlet and a plurality of oxygen outlets shaped and positioned for creating a converging, rotating stream of oxygen which intersects with any fuel issuing from the fuel outlet. Such oxygen/fuel interaction results in two zones of combustion and a recirculation effect which assists in the complete or substantially complete combustion of undesirable exhaust gas components.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: March 16, 1999
    Assignee: The BOC Group plc
    Inventor: Christian J. Feldermann
  • Patent number: 5878598
    Abstract: Air is separated into oxygen and nitrogen in a double rectification column comprising a higher pressure rectification column and a lower pressure rectification column. Liquid nitrogen reflux for the separation is provided by condensing nitrogen vapor taken from the column in a condenser-reboiler. Additional separation is performed in an intermediate pressure rectification column. A first stream of argon-enriched vapor is withdrawn from an intermediate region of the lower pressure rectification column and has an argon fraction separated from it in a first side rectification column. A second stream of argon-enriched vapor is similarly withdrawn and is separated in a second side rectification column which provides vapor to heat a reboiler associated with the intermediate pressure rectification column. Alternatively a stream of oxygen vapor can be so employed instead of the second argon-enriched vapor stream.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: March 9, 1999
    Assignee: The BOC Group plc
    Inventor: Paul Higginbotham
  • Patent number: 5870897
    Abstract: A refrigeration apparatus includes a container in which are situated a plurality of eutectic chilling elements and a spraybar for dispensing a mist of liquid cryogen into a region R in which product to be refrigerated is to be stored. Liquid cryogen is used to freeze the eutectic and is then passed to the spray bar.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: February 16, 1999
    Assignee: The BOC Group plc
    Inventors: Michael Barr, Stephen N. Waldron, Michael E. Garrett
  • Patent number: 5868007
    Abstract: Air is separated in an arrangement of rectification columns including a double rectification column for separating oxygen and nitrogen from the air. The double rectification column comprises a higher pressure rectification column and a lower pressure rectification column. There is in addition a side rectification column for separating argon from a stream of argon-enriched oxygen/vapour withdrawn from the lower pressure rectification column. An intermediate pressure rectification column is employed to separate further nitrogen (oxygen-depleted vapour) from the air. An upward flow of vapour through the intermediate pressure rectification column is created by operation of a reboiler to boil liquid in the bottom of the column. In addition a flow of vaporised air is introduced into an intermediate mass transfer region of the column.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: February 9, 1999
    Assignee: The BOC Group plc
    Inventor: Paul Higginbotham
  • Patent number: 5868199
    Abstract: A liquefied gas mixture comprising at least two components of which one is more volatile than the other or others is boiled in an apparatus including stripping passages for vaporising part of a flow of the mixture. The passages are arranged alternately with condensing passages. The stripping passages each have at least one heat exchange surface which is heated to a temperature which causes the liquid to boil and along which the liquefied gas mixture flows in countercurrent mass exchange relationship with a vapour flow evolved from such liquid. The more volatile component is progressively stripped from the liquefied gas mixture such that the vapour flow is enriched in its direction of flow in the more volatile component and the mixture itself is depleted of the more volatile component in its direction of flow. Accordingly, separation of the mixture takes place in addition to its boiling.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: February 9, 1999
    Assignee: The BOC Group plc
    Inventor: John Terence Lavin
  • Patent number: 5863195
    Abstract: A burner is provided with a burner block having a recess formed in the back thereof for receiving a fuel atomiser and a plurality of oxygen inlets for creating a converging cone of oxygen for intersection with any fuel issuing from the atomiser. Such an arrangement also provides a protective wall for protecting the atomiser from the harsh environment to which the burner is exposed and simplifies the oxygen supply arrangements.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: January 26, 1999
    Assignee: The BOC Group plc
    Inventor: Christian J. Feldermann
  • Patent number: 5863513
    Abstract: An elevated pressure nitrogen stream from an air separation plant is used to provide cooling for one or more sulphur condensers in an oxygen-enhanced Claus process for recovering sulphur.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: January 26, 1999
    Assignee: The BOC Group plc
    Inventor: Thomas Rathbone
  • Patent number: 5862680
    Abstract: Air is separated in an arrangement of rectification columns comprising a double rectification column having a higher pressure column and a lower pressure rectification column, an intermediate pressure rectification column, and a side rectification column communicating with the lower pressure column. The side rectification column is provided with a condenser and the intermediate pressure rectification column with a reboiler and a further condenser. A stream of oxygen-enriched liquid is withdrawn from the bottom of the higher pressure column through an outlet and is separated in the intermediate pressure rectification column. The reboiler is heated by a stream typically withdrawn from the side rectification column through an outlet thereof. The condensers of the side rectification column and the intermediate column are cooled by streams having different oxygen mole fractions.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: January 26, 1999
    Assignee: The BOC Group plc
    Inventors: Paul Higginbotham, John Douglas Oakey
  • Patent number: 5863317
    Abstract: An apparatus for separating a gas-liquid mixture into component parts having a coalescing filter mounted on a rotatable shaft. The gas-liquid mixture is directed to the coalescing filter in a generally radial inward direction relative to the shaft and the retained liquid is spun in a generally radial outward direction from the filter by centrifugal force associated with the rotation of the shaft and thereby the coalescing filter.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: January 26, 1999
    Assignee: The BOC Group plc
    Inventors: John Cambridge Smith, Alex George Hunter
  • Patent number: 5858069
    Abstract: There is described an improvement in a process of dispersing/dissolving a gas in a body of aqueous liquid by dispersing/dissolving the gas in a stream of the liquid and introducing the stream into the body of liquid comprising introducing a quantity of non-ionic surfactant, anionic surfactant or mixtures thereof into the liquid thereby inhibiting coalescence of gas bubbles and enhancing dispersion/dissolution.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: January 12, 1999
    Assignee: The BOC Group plc
    Inventor: Stephen B. Harrison
  • Patent number: 5852940
    Abstract: Air is separated in an arrangement of rectification columns comprising a double rectification column (which has a higher pressure column and a lower pressure column), an intermediate pressure rectification column and a side rectification column communicating with the lower pressure column. The side rectification column is provided with a condenser and the intermediate pressure rectification column with a reboiler and a condenser. A stream of oxygen-enriched liquid and a stream of liquid air are withdrawn from the higher pressure column through outlets and are separated in the intermediate pressure rectification column. The reboiler is heated by a stream typically withdrawn from the side rectification column through an outlet. A stream of liquid is withdrawn through an outlet at the bottom of the intermediate pressure rectification column is used to cool the condenser and is separated in the lower pressure rectification column.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: December 29, 1998
    Assignee: The BOC Group plc
    Inventors: Paul Higginbotham, John Douglas Oakey
  • Patent number: 5848873
    Abstract: A vacuum pump of the regenerative type comprising a rotor and a stator body in which the rotor is adapted for rotation. The rotor has a series of blades positioned in an annular array on a side of the rotor. The stator has an annular channel within which the blades can rotate having a cross-sectional area greater than that of the individual blades except for a small part of the channel which has a reduced cross-section providing a close clearance for the blades. Further, the rotor has at least two series of blades positioned in concentric annular arrays on a side of the rotor and the stator has a corresponding number of channels within which the blades of the arrays can rotate. The channels are linked to form a continuous passageway through which gas being evacuated by the pump can pass.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: December 15, 1998
    Assignee: The BOC Group plc
    Inventor: Nigel Paul Schofield
  • Patent number: 5846066
    Abstract: A mechanical vacuum pump having mounted in each of at least three pumping chambers a pair of intermeshing rotors. A first rotor of each pair being mounted for rotation on a first shaft passing through the chambers and a second rotor of each pair being mounted for rotation on a second shaft passing through the chambers. The first and second shafts are driven in contra-rotating directions to effect a sequential pumping action by the pairs of rotors in each chamber in respect of gas being pumped between a pump inlet and a pump outlet. The pump possesses at least one chamber with claw-type profile rotors and one ore more chambers with roots-type profile rotors. The chamber nearest the pump outlet has a rotor with a roots-type profile.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: December 8, 1998
    Assignee: The Boc Group plc
    Inventor: Alan Paul Troup
  • Patent number: 5846227
    Abstract: A catheter assembly includes a hollow needle having a sharpened distal tip which is movable between a position in which the needle is located within a housing and a patient penetrating position in which the distal tip extends beyond the distal end of a catheter. The catheter and a catheter hub form a catheter assembly which is supported on a catheter hub support.The catheter hub support is a one-piece molding and includes a gaskets and means that wipe the outside of the needle when the needle is withdrawn from the patient back within the housing to a needle protected position. The function of gasket means is to retard the flow of blood between the catheter hub and the catheter hub support.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: December 8, 1998
    Assignee: The BOC Group plc
    Inventor: Roland J. Osterlind
  • Patent number: 5845811
    Abstract: A capsule for storing a propellant fluid, for example, helium under pressure comprises a hollow body which includes a frangible area. An anchor member attaches an arm to the frangible area such that when a force is applied to the arm, said force together with the helium under pressure will cause the frangible area to rupture outwardly of the hollow body thereby to release the helium.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: December 8, 1998
    Assignee: The BOC Group Plc
    Inventors: Evelyn A. Shervington, David W. Birch
  • Patent number: 5836166
    Abstract: The present invention provides a food freezing apparatus and method in which food is passed through an elongated tube in which it is subjected to both crust and atmospheric freezing before being removed for packing. The crust freezing is facilitated by spraying liquid cryogen onto the outside of the tube at an upstream portion thereof.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: November 17, 1998
    Assignee: The BOC Group plc
    Inventor: David G. Wardle
  • Patent number: 5831147
    Abstract: A method and apparatus for leak testing an article in which an evacuable test chamber and a mass spectrometer leak detector are provided. The conduit links the test chamber and the mass spectrometer. A first valve is provided nearer the test chamber and a second valve is provided nearer the leak detector for controlling the flow through the conduit and for defining between the valves the trapped volume that is associated with the conduit. The trapped volume is evacuated with the first valve closed and the second valve opened. The pressure differential between the first point situated intermediate the first valve and the test chamber is measured and a second point situated intermediate the second valve and the leak detector is measured. The pressure differential between the first and second points is measured and a pressure differential reference point is determined. The second valve is closed to form the trapped volume and the first valve is opened to communicate the trapped volume and the evacuation chamber.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: November 3, 1998
    Assignee: The BOC Group plc
    Inventor: Stephen D. Hoath
  • Patent number: 5819556
    Abstract: Air is separated in an arrangement of rectification columns comprising a double rectification column (which has a higher pressure column and a lower pressure column), an intermediate pressure rectification column, and a side rectification column communicating with the lower pressure column. The side rectification column is provided with a condenser, and the intermediate pressure rectification column with a reboiler and a further condenser. A stream of oxygen-enriched liquid is withdrawn from the bottom of the higher pressure column through an outlet and is separated in the intermediate pressure rectification column. The reboiler is heated by a stream typically withdrawn from the side rectification column through an outlet. A stream of liquid is withdrawn from the bottom of the intermediate pressure rectification column, is employed to cool the further condenser of the intermediate pressure rectification column, and is partially vaporised therein.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: October 13, 1998
    Assignee: The BOC Group plc
    Inventors: Paul Higginbotham, John Douglas Oakey
  • Patent number: 5813252
    Abstract: A fractionation column has a first vapor inlet to a bottom mass exchange region of the column communicating with a source of vapor mixture to be separated and a second vapor inlet to an intermediate mass exchange region of the column. A valve means is operable to place the second inlet selectively in communication with the source of vapor mixture to be separated. The fractionation column may form part of an air separation apparatus.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: September 29, 1998
    Assignee: The BOC Group plc
    Inventor: Paul Higginbotham
  • Patent number: 5809802
    Abstract: An air separation method and apparatus in which a flow of air is subjected to a first rectification so as to separate therefrom an oxygen fraction and a nitrogen fraction. An argon-containing stream comprising argon, oxygen, and, as an impurity, nitrogen is withdrawn from the first rectification and is subjected to a second rectification so as to separate an impure argon fraction containing nitrogen. Nitrogen impurity is stripped from a stream of the argon fraction in a stripping column. A stream of sub-cooled liquid cools a condenser associated with an upper region of the stripping column by indirect heat exchange with condensing argon-nitrogen vapor mixture, and passes out of said indirect heat exchange still in sub-cooled state.
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: September 22, 1998
    Assignee: The BOC Group plc
    Inventor: Thomas Rathbone