Patents by Inventor Nigel Paul Schofield

Nigel Paul Schofield has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20200347851
    Abstract: A turbomolecular pump and method and apparatus for controlling the pressure in a process chamber using such a pump is disclosed. The turbomolecular comprises: a rotor comprising a plurality of blades on a rotatable shaft; a control motor for driving the rotatable shaft; wherein the control motor is sized to output a power that is more than three times larger than a power required to drive the shaft at a constant velocity that is sufficiently high to provide an exhaust pressure of 5 millibars.
    Type: Application
    Filed: December 10, 2018
    Publication date: November 5, 2020
    Inventors: James Alexander HAYLOCK, Christopher Mark BAILEY, Nigel Paul SCHOFIELD
  • Publication number: 20200271118
    Abstract: A drag pump for pumping gas and a set of vacuum pumps including the drag pump are disclosed. The drag pump comprises: a rotor configured to rotate within a stator component and to drive a gas to be pumped from a gas inlet to a gas outlet; magnetic bearings for rotatably mounting the rotor within the pump; wherein at least a portion of the rotor and stator component configured to contact the gas to be pumped are configured for operation at temperatures above 130° C.
    Type: Application
    Filed: September 19, 2018
    Publication date: August 27, 2020
    Inventor: Nigel Paul Schofield
  • Publication number: 20200102958
    Abstract: A twin shaft pump may include two cooperating rotors configured to rotate in opposite directions about parallel axes of rotation; a stator comprising a stator bore in which the rotors are mounted to rotate. The stator bore includes a central part between the two axes of rotation, and an outer part outside of the two axes, the rotors being configured to have cooperating dimensions with the stator bore such that an outer edge of each rotor that is remote from the other rotor seals with the stator bore when rotating in at least a portion of the outer part. A fluid inlet is provided in the stator bore, at least a portion of the fluid inlet being in the central part of the stator bore between the axes of rotation. A fluid outlet is provide in an opposing surface of the stator bore, the fluid outlet being in the central part of the stator bore.
    Type: Application
    Filed: June 7, 2018
    Publication date: April 2, 2020
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Patent number: 10533552
    Abstract: A rotary screw vacuum pump 10 comprises a housing 12 that has a lower pressure inlet region 14 and a higher pressure outlet region 16 and two intermeshing screws 18 disposed in the chamber and configured to cooperably rotate to compress a gas in working chambers formed between them and the housing while pumping the gas from the lower pressure inlet region to the higher pressure outlet region. The housing 12 has a least one liquid inlet 20 to admit a sealing liquid to seal the working chambers. The intermeshing screws 18 comprise Quimby-type screws.
    Type: Grant
    Filed: November 10, 2015
    Date of Patent: January 14, 2020
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20190368354
    Abstract: A multi-stage vacuum pump having an interstage coupling unit vacuum pump may include a first inter-stage coupling part defining a first portion of a void for receiving a common rotor shared by adjacent stages of the multi-stage vacuum pump; and a second inter-stage coupling part separable from the first inter-stage coupling part, the second inter-stage coupling part defining a second portion of the void for receiving the common rotor shared by adjacent stages of the multi-stage vacuum pump. In this way, a coupling is provided which enables an assembled rotor and assembled stages of the vacuum pump to be fixed together, since the assembled rotor can be received within the separable parts of the coupling which, in turn, can be fitted to the assembled adjacent stages. This enables the mechanical integrity of the rotor and adjacent stages to be preserved while still facilitating assembly of the multi-stage vacuum pump.
    Type: Application
    Filed: January 18, 2018
    Publication date: December 5, 2019
    Inventors: Michael Henry North, Nigel Paul Schofield
  • Publication number: 20190368489
    Abstract: A pump assembly may include a rotor having a rotor shaft portion; a stator having a bore portion defining a bore for receiving the rotor shaft portion; and a circumferential protrusion extending radially into the bore between the bore portion and the rotor shaft portion, wherein at least one of the protrusion and a corresponding surface of the rotor shaft portion or the bore portion is configured to be abraded by the other upon experiencing contact therewith. In this way, the gap between the bore portion and the rotor shaft portion may be at least partially filled by the circumferential protrusion in order to provide a seal. The protrusion and one of the bore portion and the rotor shaft portion may be formed from different hardness materials.
    Type: Application
    Filed: December 13, 2017
    Publication date: December 5, 2019
    Inventors: Nigel Paul Schofield, Alan Ernest Kinnaird Holbrook
  • Publication number: 20190309748
    Abstract: A scroll vacuum pump includes an orbiting scroll having a wall extending axially from an orbiting scroll base towards a fixed scroll, the fixed scroll having a fixed scroll wall extending axially from a fixed scroll base towards the orbiting scroll; an axially extending drive shaft having an eccentric shaft portion so that rotation of the eccentric shaft portion imparts an orbiting motion to the orbiting scroll relative to the fixed scroll; and an axial thrust bearing arrangement including an array of ball bearings for bearing against the orbiting scroll base in an axial direction, each ball bearing describing a circular path over the orbiting scroll base during orbiting motion; at least one thrust surface for bearing against the array of ball bearings; and an adjustment mechanism for adjusting the axial position of said at least one thrust surface and thereby the axial position of the orbiting scroll base.
    Type: Application
    Filed: May 25, 2017
    Publication date: October 10, 2019
    Inventor: Nigel Paul Schofield
  • Patent number: 10337517
    Abstract: An improved vacuum pump mechanism is described in which an intersecting solid or perforated element is arranged to intersect a channel member. Relative movement of the intersecting solid or perforated element and channel member causes gas molecules to be urged from inlet to an outlet of the pump. Gas molecules are constrained within the channel member and interaction of the gas molecules with the flat and smooth surfaces of the intersecting solid or perforated member influence momentum of the gas molecules so that they are directed towards the outlet. In one embodiment, the channel member is formed as a helix and the intersecting solid or perforated elements are disk-shaped. An alternative embodiment is provided having the channel member configured as a spiral and the perforated elements as cylindrical skirts. The pump provides significant improvements in pump capacity, reduced power consumption and size of pump.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: July 2, 2019
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Ian David Stones, Stephen Dowdeswell
  • Patent number: 10309401
    Abstract: A vacuum exhaust system which exhausts gas from chambers and which comprises a plurality of branch channels for the exhaustion of the gas from the chambers, a main pipeline in the form of a confluence of the plurality of branch channels, channel open-close valves fitted to correspond with each of the said plurality of branch channels, a channel-switching valve connecting the main channel and a plurality of selection channels and allowing flow between the main channel and any one of the plurality of selection channels, a first pump which functions as a gas exhaust means in the molecular flow region of the gas and is fitted to one of the plurality of branch channels, and second pumps which function as gas exhaust means in the viscous flow region of the gas and are fitted to the plurality of selection channels.
    Type: Grant
    Filed: January 6, 2016
    Date of Patent: June 4, 2019
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Andrew Seeley, Katsumi Nishimura, Katsunori Takahashi
  • Patent number: 10161399
    Abstract: The present invention provides a scroll pump comprising: a scroll mechanism having an orbiting scroll and a fixed scroll; a drive shaft having a concentric shaft portion and an eccentric shaft portion connected to the orbiting scroll. The shaft is arranged to be driven by a motor so that rotation of the shaft imparts an orbiting motion to the orbiting scroll relative to the fixed scroll for pumping fluid along a flow path from an inlet to an outlet of the scroll mechanism. An axial lip seal is located between the orbiting scroll and the fixed scroll for resisting leakage of fluid from outside the scroll mechanism into the flow path.
    Type: Grant
    Filed: June 10, 2013
    Date of Patent: December 25, 2018
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20180328410
    Abstract: A twin-shaft pump comprising: two shafts configured to rotate in synchronisation, each of the shafts comprising a gear mounted thereon, the gears each comprising gear wheels, the gear wheels being configured to intermesh to provide the synchronised rotation; an oil reservoir comprising a porous material, the reservoir being configured when supplied with oil to retain the oil within the porous material; and at least one wick extending from the oil reservoir towards a first of the two shafts and operable to supply oil by capillary action from the porous material along the wick to lubricate the gears.
    Type: Application
    Filed: May 9, 2018
    Publication date: November 15, 2018
    Inventor: Nigel Paul Schofield
  • Patent number: 9920761
    Abstract: The present invention relates to a rotor for a vacuum pump 150 having a roots pumping mechanism, the rotor comprising at least two hollow lobes 160, 162, 164, 166, each lobe having an outer wall 208 which defines a lobe profile, a hollow cavity 210 generally inward of the outer wall, and at least one strengthening rib 226 located in the cavity to resist stress on the lobes generated during rotation.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: March 20, 2018
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20180023566
    Abstract: A rotary screw vacuum pump 10 comprises a housing 12 that has a lower pressure inlet region 14 and a higher pressure outlet region 16 and two intermeshing screws 18 disposed in the chamber and configured to cooperably rotate to compress a gas in working chambers formed between them and the housing while pumping the gas from the lower pressure inlet region to the higher pressure outlet region. The housing 12 has a least one liquid inlet 20 to admit a sealing liquid to seal the working chambers. The intermeshing screws 18 comprise Quimby-type screws.
    Type: Application
    Filed: November 10, 2015
    Publication date: January 25, 2018
    Inventor: Nigel Paul Schofield
  • Publication number: 20180003178
    Abstract: A vacuum exhaust system which exhausts gas from chambers and which comprises a plurality of branch channels for the exhaustion of the gas from the chambers, a main pipeline in the form of a confluence of the plurality of branch channels, channel open-close valves fitted to correspond with each of the said plurality of branch channels, a channel-switching valve connecting the main channel and a plurality of selection channels and allowing flow between the main channel and any one of the plurality of selection channels, a first pump which functions as a gas exhaust means in the molecular flow region of the gas and is fitted to one of the plurality of branch channels, and second pumps which function as gas exhaust means in the viscous flow region of the gas and are fitted to the plurality of selection channels.
    Type: Application
    Filed: January 6, 2016
    Publication date: January 4, 2018
    Inventors: Nigel Paul Schofield, Andrew Seeley, Katsumi Nishimura, Katsunori Takahashi
  • Publication number: 20170350395
    Abstract: A vacuum pumping arrangement includes a first primary pump having an inlet and an outlet, and a first common pumping line fluidly connected to the inlet, the first common pumping line including a plurality of first common pumping line inlets each of which is fluidly connectable to at least one vacuum process chamber forming the semiconductor fabrication tool, the first primary pump and the first common pumping line handling deposition process flows. The pumping arrangement further including a second primary pump having an inlet and an outlet, and a second common pumping line fluidly connected to the inlet of the second primary pump, the second common pumping line including a plurality of second pumping line inlets each of which is fluidly connectable to at least one process chamber forming the semiconductor fabrication tool, the second primary pump and the second common pumping line handling cleaning process flows.
    Type: Application
    Filed: January 6, 2016
    Publication date: December 7, 2017
    Inventors: Nigel Paul SCHOFIELD, Andrew SEELEY, Jack Raymond TATTERSALL, Neil TURNER
  • Publication number: 20160369807
    Abstract: A kinetic energy recovery system is provided comprising a flywheel located in a first vacuum enclosure and a second vacuum enclosure comprising an inlet in fluid communication with the exhaust of the first vacuum enclosure and arranged to be maintained at a pressure less than atmosphere for reducing the pressure at the outlet of the first vacuum enclosure, the second vacuum enclosure comprising an exhaust through which gas can be pumped periodically at indeterminate intervals for maintaining the second vacuum enclosure at a pressure less than atmosphere. Thus an improved efficiency Kinetic energy system.
    Type: Application
    Filed: June 14, 2016
    Publication date: December 22, 2016
    Applicant: Edwards Limited
    Inventors: NIGEL PAUL SCHOFIELD, David John GOODWIN
  • Publication number: 20160369783
    Abstract: The present invention provides an improved kinetic energy recovery and/or storage system for vehicles or other devices employing kinetic energy recovery systems comprising a flywheel supported for rotation in a first vacuum enclosure for receiving energy from and dissipating energy to one or more parts of a vehicle; a scroll vacuum pumping arrangement having an inlet arranged to be in fluid communication with an outlet of the first vacuum enclosure for evacuating the first vacuum enclosure; and a second vacuum enclosure having an inlet in fluid communication with an exhaust of the scroll pumping arrangement and arranged to be maintained at a pressure less than atmosphere for reducing the pressure at the exhaust of the scroll pumping arrangement, wherein the second vacuum enclosure comprising an outlet through which gas can be pumped periodically for maintaining the second vacuum enclosure at a pressure less than atmosphere.
    Type: Application
    Filed: June 14, 2016
    Publication date: December 22, 2016
    Applicant: Edwards Limited
    Inventor: NIGEL PAUL SCHOFIELD
  • Publication number: 20160369806
    Abstract: A vehicle comprising a kinetic energy recovery system having a flywheel supported for rotation in a vacuum enclosure wherein a first vacuum pumping arrangement evacuates the vacuum enclosure and a second vacuum pumping arrangement of the vehicle evacuates the recovery system. The flywheel is supported for rotation on a common drive shaft with the first vacuum pumping mechanism.
    Type: Application
    Filed: June 14, 2016
    Publication date: December 22, 2016
    Applicant: Edwards Limited
    Inventors: NIGEL PAUL SCHOFIELD, David John GOODWIN
  • Patent number: 9334873
    Abstract: A pump comprising a regenerative pumping mechanism having a generally disc-shaped rotor mounted on an axial shaft for rotation relative to a stator. The rotor has first and second surfaces each having a series of shaped recesses formed in concentric circles thereon, and a stator channel formed in a surface of the stator which faces one of the rotor's first or second surfaces. The rotor divides the a gas flow path into sub-flow paths such that gas can flow towards the outlet simultaneously along both the first surface and the second surface of the rotor.
    Type: Grant
    Filed: May 18, 2010
    Date of Patent: May 10, 2016
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20160097390
    Abstract: The present invention relates to a rotor for a vacuum pump 150 having a roots pumping mechanism, the rotor comprising at least two hollow lobes 160, 162, 164, 166, each lobe having an outer wall 208 which defines a lobe profile, a hollow cavity 210 generally inward of the outer wall, and at least one strengthening rib 226 located in the cavity to resist stress on the lobes generated during rotation.
    Type: Application
    Filed: December 14, 2015
    Publication date: April 7, 2016
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell