Edwards Limited

Stephen Dowdeswell

Nigel Paul Schofield

Ian David Stones

Alan Ernest Kinnaird Holbrook

Peter Hugh Birch

Neil Turner

David Bedwell

Sivabalan Kailasam

William Foote

Simon Stevens

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.

Multi-stage turbomolecular pump

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.

Axial flow vacuum pump with curved rotor and stator blades

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.

Vacuum pump

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.

Temperature control of a pumped gas flow

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. The fluid inlet and fluid outlet are arranged such that on rotation of the rotors, the rotors each move a pumping chamber between the fluid inlet and the fluid outlet; wherein at least a portion of the fluid inlet is arranged to extend beyond the central part of the stator bore.

Twin shaft pumps and a method of pumping

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.

Gas transfer vacuum pump

The present invention relates to a rotor for a vacuum pumphaving a roots pumping mechanism, the rotor comprising at least two hollow lobes, each lobe having an outer wallwhich defines a lobe profile, a hollow cavitygenerally inward of the outer wall, and at least one strengthening riblocated in the cavity to resist stress on the lobes generated during rotation.

Vacuum pump rotor for a vacuum pump having a roots pumping mechanism

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.

Vacuum pump with longitudinal and annular seals

A multi-stage, clam shell, vacuum pump comprises two housing components () 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 () 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 () is provided, located between the sealing means () and the array of chambers (). The channels serve to protect the sealing means () 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.

Multi stage, clam shell vacuum pump

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. Thus, powder entrained in the pumped gas is effectively removed from pumping volume in a way which reduces the likelihood of any solid material causing the pump to seize: the channel can be arranged so that the solid material is 'flung' towards the outlet or away from a meshing zone where rotors mesh with one another.

Roots pumps

A vacuum pump housing comprises first () and second half-shell stator components () defining a plurality of pumping chambers separated by partition members (). Each pumping chamber comprises an inlet port () for receiving fluid and an outlet port () 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 () for conveying fluid between the pumping chambers. Each transfer channel preferably comprises first and second portions located on opposite sides of the housing.

Growing community of inventors

Cuckfield, United Kingdom

Stephen Dowdeswell