Patents by Inventor Stephen Dowdeswell

Stephen Dowdeswell 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: 11841021
    Abstract: A heat exchanger for changing a temperature of a pumped gas flow and a pump comprising the heat exchanger is disclosed. The heat exchanger comprises: at least one tube configured to contain a flow of fluid; said at least one tube being at least partially embedded within a block of material; wherein said heat exchanger comprises mounting means configured to mount said heat exchanger adjacent to a gas port of a pump such that a least a portion of said heat exchanger extends into a path for gas flow flowing through said gas port; wherein the mounting means comprises a flange, the flange being configured to connect with the gas port of the pump, the block being mounted to the flange such that the block extends towards the rotor of the pump when the flange is connected with the gas port of the pump.
    Type: Grant
    Filed: February 28, 2018
    Date of Patent: December 12, 2023
    Assignee: Edwards Limited
    Inventors: William Foote, Stephen Dowdeswell, David Bedwell, Simon Stevens
  • 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: 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
  • 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: 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: 20200173444
    Abstract: A heat exchanger for changing a temperature of a pumped gas flow and a pump comprising the heat exchanger is disclosed. The heat exchanger comprises: at least one tube configured to contain a flow of fluid; said at least one tube being at least partially embedded within a block of material; wherein said heat exchanger comprises mounting means configured to mount said heat exchanger adjacent to a gas port of a pump such that a least a portion of said heat exchanger extends into a path for gas flow flowing through said gas port; wherein the mounting means comprises a flange, the flange being configured to connect with the gas port of the pump, the block being mounted to the flange such that the block extends towards the rotor of the pump when the flange is connected with the gas port of the pump.
    Type: Application
    Filed: February 28, 2018
    Publication date: June 4, 2020
    Inventors: William Foote, Stephen Dowdeswell, David Bedwell, Simon Stevens
  • 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: 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: 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
  • Patent number: 9551333
    Abstract: A multi-stage vacuum pump may include first and second half-shell components defining a plurality of pumping chambers and for assembly together along respective longitudinal extending faces; first and second end stator components for assembly at respective longitudinal seals for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and annular seals for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein the longitudinal seals have end portions which abut against the annular seals for sealing therebetween and the first and second half-shell stator components have formations for resisting movement of the end portions away from the annular seals when the end portions are compressed between the first and second half-shell stator components.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: January 24, 2017
    Assignee: Edwards Limited
    Inventors: Neil Turner, Stephen Dowdeswell, Sivabalan Kailasam, Alan Ernest Kinnaird Holbrook
  • 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
  • Patent number: 9279426
    Abstract: A multi-stage, clam shell, vacuum pump comprises two housing components (12) which are to be sealingly connected to one another such that an array of chambers extending longitudinally from an inlet region of the pump to an outlet region of the pump is defined thereby. Sealing means (30) are provided within the vacuum pump, between the two housing components, to prevent transfer of fluid in to and out of the vacuum pump where said components are connected. An array of discrete, elongate channels (33, 34, 36, 38) is provided, located between the sealing means (30) and the array of chambers (14, 16, 18, 20, 22). The channels serve to protect the sealing means (30) from fluid that passes through the chambers during operation of the vacuum pump. Each channel is configured to receive a barrier fluid having a different pressure than a barrier fluid to be received by an adjacent channel.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: March 8, 2016
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20150377239
    Abstract: A vacuum pump may include a regenerative pumping mechanism and a drag pumping mechanism. The regenerative pumping mechanism may include a generally disc-shaped member mounted on an axial shaft for rotation relative to a stator of the regenerative pumping mechanism. The drag pumping mechanism may include a generally cylindrical-shaped member mounted at an outer circumferential portion of the disc-shaped member for rotation about the axial shaft relative to a stator of the drag pumping mechanism.
    Type: Application
    Filed: February 15, 2013
    Publication date: December 31, 2015
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20150037137
    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: Application
    Filed: January 24, 2013
    Publication date: February 5, 2015
    Inventors: Nigel Paul Schofield, Ian David Stones, Stephen Dowdeswell
  • Publication number: 20140079581
    Abstract: The present invention relates to a rotor for a vacuum pump having a roots pumping mechanism, the rotor comprising at least two hollow lobes, each lobe having an outer wall which defines a lobe profile, a hollow cavity generally inward of the outer wall, and at least one strengthening rib located in the cavity to resist stress on the lobes generated during rotation.
    Type: Application
    Filed: April 23, 2012
    Publication date: March 20, 2014
    Applicant: EDWARDS LIMITED
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20140017062
    Abstract: A multi-stage vacuum pump may include first and second half-shell components defining a plurality of pumping chambers and for assembly together along respective longitudinal extending faces; first and second end stator components for assembly at respective longitudinal seals for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and annular seals for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein the longitudinal seals have end portions which abut against the annular seals for sealing therebetween and the first and second half-shell stator components have formations for resisting movement of the end portions away from the annular seals when the end portions are compressed between the first and second half-shell stator components.
    Type: Application
    Filed: January 17, 2012
    Publication date: January 16, 2014
    Applicant: EDWARDS LIMITED
    Inventors: Neil Turner, Stephen Dowdeswell, Sivabalan Kailasam, Alan Ernest Kinnaird Holbrook
  • Patent number: 8500422
    Abstract: A vacuum pump housing comprises first (12) and second half-shell stator components (14) defining a plurality of pumping chambers separated by partition members (26, 28, 30, 32). Each pumping chamber comprises an inlet port (42, 44, 46, 48, 50) for receiving fluid and an outlet port (54, 56, 58, 60, 62) through which pumped fluid is exhausted from the chamber. The inlet ports are open on an external surface of the first stator component, and the outlet ports are open on an opposing external surface of the second stator component. The stator components further define transfer channels (66, 68, 70, 72) for conveying fluid between the pumping chambers. Each transfer channel preferably comprises first and second portions located on opposite sides of the housing.
    Type: Grant
    Filed: October 1, 2007
    Date of Patent: August 6, 2013
    Assignee: Edwards Limited
    Inventors: Stephen Dowdeswell, Nigel Paul Schofield, Peter Hugh Birch
  • Patent number: 8500425
    Abstract: A Roots vacuum pump stator is arranged to house a pair of intermeshing rotors, said stator being characterized in that it comprises a director or deflector arranged to direct solid material entrained in a gas pumped through the pump towards the outlet. In other words, the stator according to the present invention has a means for directing or deflecting powder or solid material entrained in a gas being pumped directly towards an outlet of the pump or out of the pump. The directing means can comprise a channel disposed between the arcuate surface and the outlet, said channel comprising a portion that engages the arcuate surface prior to the bottom-dead-centre position and which extends away from the rotor's axis of rotation towards the pump outlet.
    Type: Grant
    Filed: October 9, 2009
    Date of Patent: August 6, 2013
    Assignee: Edwards Limited
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20100226808
    Abstract: A multi-stage, clam shell, vacuum pump comprises two housing components (12) which are to be sealingly connected to one another such that an array of chambers extending longitudinally from an inlet region of the pump to an outlet region of the pump is defined thereby. Sealing means (30) are provided within the vacuum pump, between the two housing components, to prevent transfer of fluid in to and out of the vacuum pump where said components are connected. An array of discrete, elongate channels (33, 34, 36, 38) is provided, located between the sealing means (30) and the array of chambers (14, 16, 18, 20, 22). The channels serve to protect the sealing means (30) from fluid that passes through the chambers during operation of the vacuum pump. Each channel is configured to receive a barrier fluid having a different pressure than a barrier fluid to be received by an adjacent channel.
    Type: Application
    Filed: October 1, 2008
    Publication date: September 9, 2010
    Inventors: Nigel Paul Schofield, Stephen Dowdeswell
  • Publication number: 20100119399
    Abstract: A vacuum pump housing comprises first (12) and second half-shell stator components (14) defining a plurality of pumping chambers separated by partition members (26, 28, 30, 32). Each pumping chamber comprises an inlet port (42, 44, 46, 48, 50) for receiving fluid and an outlet port (54, 56, 58, 60, 62) through which pumped fluid is exhausted from the chamber. The inlet ports are open on an external surface of the first stator component, and the outlet ports are open on an opposing external surface of the second stator component. The stator components further define transfer channels (66, 68, 70, 72) for conveying fluid between the pumping chambers. Each transfer channel preferably comprises first and second portions located on opposite sides of the housing.
    Type: Application
    Filed: October 1, 2007
    Publication date: May 13, 2010
    Applicant: EDWARDS LIMITED
    Inventors: Stephen Dowdeswell, Nigel Paul Schofield, Peter Hugh Birch