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).

  • Patent number: 11933284
    Abstract: A vacuum exhaust system includes a plurality of turbo pumps that evacuate a plurality of vacuum chambers. A plurality of chamber valves are positioned between the turbo pumps and the plurality of vacuum chambers. A plurality of branch channels are each connected to a corresponding exhaust of the plurality of turbo pumps and a main channel is formed from a confluence of the branch channels. A booster vacuum pump is connected to the main channel. A backing vacuum pump is connected to an exhaust of the booster vacuum pump. A plurality of bypass channels, each having a valve, provide a fluid communication path between at least some of the plurality of vacuum chambers and the booster vacuum pump.
    Type: Grant
    Filed: November 27, 2019
    Date of Patent: March 19, 2024
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Christopher Mark Bailey, Michael Andrew Galtry, Andrew David Mann
  • Patent number: 11885341
    Abstract: A rotor support configured to rotatably mount a rotor shaft in a vacuum pump is disclosed. The rotor support comprises: a rolling bearing for rotatably supporting the shaft; an insert and at least one resilient damping member, the insert and the at least one resilient damping member surrounding the rolling bearing. The insert comprises inner and outer annular portions connected by a plurality of flexible members, the plurality of flexible members being configured to flex in a radial plane and resist movement in an axial plane, thereby absorbing radial movement of the shaft. The at least one resilient damping member is formed of an elastomeric material configured to flex in both a radial and axial direction.
    Type: Grant
    Filed: June 2, 2020
    Date of Patent: January 30, 2024
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20240018960
    Abstract: A scroll pump includes an inlet and an outlet, a fixed scroll and an orbiting scroll intermeshed with each other, wherein the fixed scroll and orbiting scroll define a space therebetween. The scroll pump further includes a biasing apparatus configured to bias the orbiting scroll against the fixed scroll, a fluid recirculation channel which extends from the space to the inlet through either the fixed scroll or the orbiting scroll, and a fluid recirculation valve disposed in the fluid recirculation channel. The fluid recirculation valve is configured to permit flow of fluid from the space to the inlet through the fluid recirculation channel or to block flow of fluid through the fluid recirculation channel. The fluid recirculation valve is configured to switch from a closed state to an open state when a pressure differential across the fluid recirculation valve is equal to or exceeds a certain threshold value.
    Type: Application
    Filed: October 28, 2021
    Publication date: January 18, 2024
    Inventors: Alan Ernest Kinnaird Holbrook, David Bedwell, Nigel Paul Schofield
  • Patent number: 11719244
    Abstract: A pump and method for pumping a gas are disclosed. The pump comprises a rotor and a stator. At least one of the rotor or stator comprises at least one liquid opening configured for fluid communication with a liquid source. The liquid opening is configured such that in response to a driving force exerted on liquid from the liquid source a stream of liquid is output from the opening, the stream of liquid forming a liquid blade between the rotor and the stator, gas confined by said stator, said rotor and said liquid blade being driven through said pump from a gas inlet towards a gas outlet.
    Type: Grant
    Filed: August 16, 2018
    Date of Patent: August 8, 2023
    Assignee: Edwards Limited
    Inventors: Ian David Stones, Nigel Paul Schofield, Ian Andrew Norton
  • Publication number: 20230184251
    Abstract: A scroll vacuum pump has an axially extending drive shaft with an eccentric shaft portion, such that rotation of the drive shaft imparts an orbiting motion to an orbiting scroll relative to a fixed scroll. An axial adjustment mechanism has a plurality of adjustment members angularly spaced around the drive shaft and extending through the pump housing towards the orbiting scroll, the plurality of adjustment members each being configured to provide an independently adjustable axial position of the orbiting scroll. A plurality of sealing means isolate the plurality of adjustment members from a pump chamber, the plurality of sealing means extending around each of the plurality of adjustment members and comprising at least one flexible portion such that one end of the sealing means may orbit relative to a fixed other end of the sealing means.
    Type: Application
    Filed: May 20, 2021
    Publication date: June 15, 2023
    Inventors: Nigel Paul Schofield, Alan Ernest Kinnaird Holbrook
  • Publication number: 20230109154
    Abstract: An axial flow vacuum pump for evacuating a chamber in a semiconductor manufacturing process comprises a rotor having a plurality of rotor blades and a stator having a plurality of stator blades, wherein the rotor blades and stator blades have a curved shape.
    Type: Application
    Filed: February 10, 2021
    Publication date: April 6, 2023
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20230042886
    Abstract: A vacuum pump, vacuum pump set and method for evacuating a semiconductor processing chamber is disclosed. The vacuum pump is configured for mounting to a semiconductor processing chamber to evacuate the chamber to pressures between 1 mbar and 5×10?2 mbar. The vacuum pump comprises: a rotor rotatably mounted within a stator. The rotor comprises a plurality of angled blades arranged along a helical path from an inlet to an outlet. The stator comprises a plurality of perforated elements arranged to intersect the helical path, the perforations allowing gas molecules travelling along the helical path to pass through the perforated elements. The rotor mounted on a magnetically levitated bearing; and the perforated elements located towards an inlet of the vacuum pump comprise a transparency of more than 40% and the perforated elements located towards an outlet of the vacuum pump comprise a transparency of more than 30%.
    Type: Application
    Filed: January 7, 2021
    Publication date: February 9, 2023
    Inventor: Nigel Paul Schofield
  • Publication number: 20230024392
    Abstract: A vacuum pump comprising: a rotor rotatably mounted within a stator; the rotor comprising a plurality of angled blades arranged along a helical path from an inlet to an outlet; the stator comprising a plurality of perforated elements forming a plurality of perforated discs arranged to intersect the helical path at different axial positions, the perforations allowing gas molecules travelling along the helical path to pass through the perforated elements. Each of the perforated discs comprises an outer curved wall forming an outer circumference of the disc and an inner curved wall forming a portion of an inner circumference of the disc, the inner circumference comprising at least one gap where there is no inner wall.
    Type: Application
    Filed: January 7, 2021
    Publication date: January 26, 2023
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20220397115
    Abstract: A scroll pump (100, 200) comprising a first scroll comprising a first spiral wall (124, 224); a second scroll comprising a second spiral wall (134, 234), the second spiral wall being intermeshed with the first spiral wall; and a pad (180, 280) formed from a different material to the first and second scrolls, the pad being located between the first and second scrolls radially inwards or outwards of the first and second spiral walls.
    Type: Application
    Filed: July 22, 2020
    Publication date: December 15, 2022
    Inventors: Alan Ernest Kinnaird Holbrook, Nigel Paul Schofield
  • Publication number: 20220299027
    Abstract: The invention provides a scroll pump comprising an orbiting scroll and a fixed scroll, wherein the orbital axis of the orbiting scroll is movable in a radial direction relative to the fixed scroll while the orbiting scroll is orbiting about its orbital axis, or wherein the fixed scroll is movable relative to the orbiting scroll in a radial direction while the orbiting scroll is orbiting about its orbital axis.
    Type: Application
    Filed: April 24, 2020
    Publication date: September 22, 2022
    Inventors: Alan Ernest Kinnaird Holbrook, Nigel Paul Schofield, David Bedwell
  • Patent number: 11421689
    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: Grant
    Filed: December 13, 2017
    Date of Patent: August 23, 2022
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Alan Ernest Kinnaird Holbrook
  • Patent number: 11401935
    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: Grant
    Filed: June 7, 2018
    Date of Patent: August 2, 2022
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20220235778
    Abstract: A rotor support configured to rotatably mount a rotor shaft in a vacuum pump is disclosed. The rotor support comprises: a rolling bearing for rotatably supporting the shaft; an insert and at least one resilient damping member, the insert and the at least one resilient damping member surrounding the rolling bearing. The insert comprises inner and outer annular portions connected by a plurality of flexible members, the plurality of flexible members being configured to flex in a radial plane and resist movement in an axial plane, thereby absorbing radial movement of the shaft. The at least one resilient damping member is formed of an elastomeric material configured to flex in both a radial and axial direction.
    Type: Application
    Filed: June 2, 2020
    Publication date: July 28, 2022
    Inventor: Nigel Paul Schofield
  • Publication number: 20220213894
    Abstract: The invention provides a crank sleeve for a scroll pump. The crank sleeve has a longitudinal axis and is configured to provide a radially extending crank offset for imparting an orbital path on an orbital scroll of the scroll pump. The crank sleeve further comprises an integrally formed counterbalance for reducing pump vibration extending radially in a direction substantially opposite to the crank offset.
    Type: Application
    Filed: April 24, 2020
    Publication date: July 7, 2022
    Inventors: Alan Ernest Kinnaird Holbrook, Nigel Paul Schofield, David Bedwell
  • Publication number: 20220049705
    Abstract: A vacuum pump comprising a turbomolecular stage and a drag stage, the vacuum pump comprising a stator and a rotor. The rotor comprises a turbomolecular rotor and a drag rotor attached together. The turbomolecular rotor comprises a hub from which a plurality of blades extend, the hub comprising a mounting portion for mounting to a spindle of a motor and a hollow cylindrical portion, the hollow cylindrical portion extending from the mounting portion towards an outlet end of the turbomolecular stage. The drag rotor comprises a cylindrical skirt and an attachment part extending away from the cylindrical skirt, the attachment part extending within the hollow cylindrical portion of the hub of the turbomolecular rotor and being attached thereto at a point that is closer to the mounting portion than to the outlet end of the turbomolecular rotor.
    Type: Application
    Filed: December 11, 2019
    Publication date: February 17, 2022
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20220010788
    Abstract: A vacuum exhaust system includes a plurality of low pressure vacuum pumps that operate in a molecular flow region and evacuate a plurality of vacuum chambers. A plurality of chamber valves are positioned between the low pressure vacuum pumps and the plurality of vacuum chambers. A plurality of branch channels are each connected to a corresponding exhaust of the plurality of low pressure vacuum pumps and a main channel is formed from a confluence of the branch channels. An intermediate vacuum pump is connected to the main channel and operates in a viscous flow region. A higher pressure vacuum pump operates in a higher pressure viscous flow region and is connected to an exhaust of the intermediate pressure vacuum pump. A plurality of bypass channels, each having a valve, provide a fluid communication path between at least some of the plurality of vacuum chambers and a higher pressure vacuum pump.
    Type: Application
    Filed: November 27, 2019
    Publication date: January 13, 2022
    Inventors: Nigel Paul Schofield, Christopher Mark Bailey, Michael Andrew Galtry, Andrew David Mann
  • Patent number: 11143191
    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: Grant
    Filed: September 19, 2018
    Date of Patent: October 12, 2021
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20210172440
    Abstract: A pump and method for pumping a gas are disclosed. The pump comprises a rotor and a stator. At least one of the rotor or stator comprises at least one liquid opening configured for fluid communication with a liquid source. The liquid opening is configured such that in response to a driving force exerted on liquid from the liquid source a stream of liquid is output from the opening, the stream of liquid forming a liquid blade between the rotor and the stator, gas confined by said stator, said rotor and said liquid blade being driven through said pump from a gas inlet towards a gas outlet.
    Type: Application
    Filed: August 16, 2018
    Publication date: June 10, 2021
    Inventors: Ian David Stones, Nigel Paul Schofield, Ian Andrew Norton
  • Patent number: 10947974
    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: Grant
    Filed: May 25, 2017
    Date of Patent: March 16, 2021
    Assignee: Edwards Limited
    Inventor: Nigel Paul Schofield
  • Publication number: 20200355190
    Abstract: A vacuum pumping arrangement comprising multiple pumping stages for evacuating a process chamber and a method of cleaning the vacuum pumping arrangement is discussed. The vacuum pumping arrangement comprises: at least one turbomolecular pumping stage; at least one further pumping stage downstream of the turbomolecular pumping stage; and at least one inlet for admitting radicals into the vacuum pumping arrangement, the at least one inlet being located downstream of the turbomolecular stage and upstream of at least one of the at least one further pumping stage.
    Type: Application
    Filed: December 19, 2018
    Publication date: November 12, 2020
    Inventors: Christopher Mark Bailey, Nigel Paul Schofield, Michael Colin Graham, Andrew Seeley