EP3571414A1 - A multiple stage turbomolecular pump with inter-stage inlet - Google Patents
A multiple stage turbomolecular pump with inter-stage inletInfo
- Publication number
- EP3571414A1 EP3571414A1 EP18700813.1A EP18700813A EP3571414A1 EP 3571414 A1 EP3571414 A1 EP 3571414A1 EP 18700813 A EP18700813 A EP 18700813A EP 3571414 A1 EP3571414 A1 EP 3571414A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- stage
- inlet
- inter
- rotor blade
- blades
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D19/00—Axial-flow pumps
- F04D19/02—Multi-stage pumps
- F04D19/04—Multi-stage pumps specially adapted to the production of a high vacuum, e.g. molecular pumps
- F04D19/042—Turbomolecular vacuum pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
- F04D29/324—Blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/403—Casings; Connections of working fluid especially adapted for elastic fluid pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/52—Casings; Connections of working fluid for axial pumps
- F04D29/522—Casings; Connections of working fluid for axial pumps especially adapted for elastic fluid pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/52—Casings; Connections of working fluid for axial pumps
- F04D29/54—Fluid-guiding means, e.g. diffusers
- F04D29/541—Specially adapted for elastic fluid pumps
- F04D29/545—Ducts
- F04D29/547—Ducts having a special shape in order to influence fluid flow
Definitions
- the field of the invention relates to turbomolecular pumps and in particular to multiple stage turbomolecular pumps with an inter-stage inlet.
- Turbomolecular pumps which provide high and ultrahigh vacuums are known. These pumps are momentum transfer pumps in which gas molecules entering the pump are given momentum by rotating rotor blades.
- the pump comprises multiple angled rotor and stator blade row pairs, the blades of the rotor blade rows are angled to push the gas molecules towards the exhaust end of the pump. In some cases there may be more rotor blade rows than there are stators such that one or more rotor blade rows may not be paired with a corresponding stator.
- a first stage will receive gas from a high vacuum chamber at a very low pressure, with subsequent stage(s) receiving gas from lower vacuum chambers at higher pressures.
- the gas has entered the pump in a radial direction via an aperture located on the circumference of the pump between two of the stages. Such an aperture requires a reasonable distance between the two stages to provide space for this gas input.
- Figure 1 shows such a conventional
- a first aspect of the present invention provides a multiple stage turbomolecular pump comprising: a higher vacuum stage comprising a plurality of rotor blade rows; a lower vacuum stage comprising a plurality of rotor blade rows of a larger diameter than said rotor blade rows of said higher vacuum stage; an inter-stage inlet for inputting gas into said turbomolecular pump between said higher vacuum and lower vacuum stages said inlet extending from an outer circumference of said pump to a radial position inside of said larger diameter and comprising a gas directing formation for directing said gas entering said pump in an axial direction.
- the inventors of the present invention recognised that the gap between rotor blade rows of different stages of a multi-stage turbomolecular pump to allow for gas input in a radial direction has led to pumps that are not compact. They also recognised that pumping stages in a turbomolecular pump may have rotor blade rows of increasing diameters in a downstream direction.
- the rotor diameter of the highest vacuum stage in a turbomolecular pump is governed by the outlet size of the chamber to which it is attached and this may be set by a standard. Subsequent rotor blade rows are not so constrained and may have larger diameters.
- said inlet comprises said gas directing formation and at least one aperture, said at least one aperture being located towards a radial outer position of said pump between said larger diameter and a diameter of at least one rotor of said higher vacuum stage.
- said at least one aperture is in a plane substantially perpendicular to an axis of said pump. Providing the aperture of the inlet in a plane substantially perpendicular to the pump axis at a position that is within the larger diameter allows for gas flowing perpendicularly through this aperture to proceed in an axial direction into the pump and onto the outer tips of this larger diameter rotor.
- a plane substantially perpendicular to the axis is deemed to be one at an angle of between 70° and 1 10° of the axis.
- said pump comprises multiple apertures located at different locations around a circumference of said pump.
- said at least a portion of said gas directing formation comprises a substantially axially oriented surface.
- said gas directing formation comprises a surface that changes from a substantially radially oriented surface at an outer circumference of said pump to a substantially axially oriented surface at a radially innermost point of said gas directing formation.
- the gas directing formation may have a number of forms, at least a portion of the formation comprises a substantially axially oriented surface, acting to deflect gas moving in a radial direction.
- a substantially axially oriented surface is considered to be a surface that is at an angle of less than 20° to the axis of the pump.
- the gas directing formation comprises a surface that changes from a substantially radially oriented surface (one at an angle of less than 20° to a radius of the pump) which brings the gas from a gas source to the pump to a substantially axially oriented surface as the gas enters the pump.
- the gas flow is delivered towards the pump from a radial direction and the direction of flow is changed to an axial direction before it is actually input into the pump.
- the gas may be delivered in an axial direction and the gas directing formation does not have a radially oriented surface.
- at least a portion of said gas directing formation is adjacent to or formed by an outer circumference of a portion of said higher vacuum stage.
- the different diameters of the different stages of the pump allows at least some of the gas directing formation to lie adjacent to, or be formed by, the outer circumference of the stage with the smaller diameter. In this way the flow of gas can be directed by a formation that is positioned alongside the stage with the smaller diameter and the inlet aperture overlaps with the larger diameter, such that the inlet does not require any substantial gap between the stages allowing for a more compact design of the pump.
- said pump comprises a stator bridge component for bridging between a smaller diameter stator in said higher vacuum stage and a larger diameter stator in said lower vacuum stage, said stator bridge component comprising a ring in a plane substantially perpendicular to the pump axis, said ring comprising multiple apertures.
- a stator bridge component is used in multiple stage pumps to bridge between the stators of the different stages which may have different diameters.
- the stator bridge comprises a ring substantially perpendicular to the pump axis.
- the ring comprises multiple apertures which are in proximity to the rotor blade of the lower vacuum stage.
- the multiple apertures of the ring are arranged around the circumference of the ring and form the apertures of the gas inlet.
- an inner diameter of said ring comprises a diameter of a stator of said higher vacuum stage and an outer diameter of said ring comprises a diameter of said stator in said lower vacuum stage.
- the ring of the stator bridge extends from a diameter of the stator of the high vacuum stage to a diameter of the larger diameter of the stators in the lower vacuum stage.
- the stator bridge has an axial portion which has a height that is set by the distance between the rotor blade rows of the two adjacent stages.
- the stator bridge has a height that is equal to or greater than the distance between two adjacent rotor blade rows within a stage and equal to or less than the distance between two rotor blade rows that are not adjacent but are separated from each other by a rotor blade row.
- the stator bridge height which sets the distance between the rotor blade rows of adjacent stages may be such that the rotor blade rows are as close as they are within a stage or at least not more than twice the distance that they are within a stage.
- At least some of said rotor blade rows within said higher vacuum stage have different diameters, a diameter of at least one rotor blade row towards said lower vacuum stage being smaller than a diameter of a rotor blade row that is more remote from said lower vacuum stage.
- the rotor blade rows within the different stages may have uniform albeit different diameters to rotor blade rows in other stages, in some embodiments the rotor blade rows within the higher vacuum stage may themselves have different diameters, the diameters of the rotor blade rows getting smaller as one progresses towards the inlet. A smaller diameter towards the inlet provides a larger space for this inlet.
- said rotor blade rows within said higher vacuum stage have diameters that taper towards said lower vacuum stage.
- the changes in diameter of the rotor blade rows may take a number of forms, in some the change may be successive, the diameters of the rotor blade rows tapering towards the lower vacuum stage.
- each of said rotor blade rows have multiple blades, said blades of said inter-stage inlet rotor blade row, said inter-stage inlet rotor blade row being said rotor blade row of said lower vacuum stage adjacent to said interstage inlet, having an angle of an outer portion of said blades adapted for pumping said gas received at said inter-stage inlet and an angle of an inner portion adapted for pumping said gas received at an inlet of said higher vacuum stage.
- the gas being pumped by the higher vacuum stage will enter the lower vacuum stage towards the middle and away from the edge of the rotor blade rows of this stage, while the gas input at the inter-stage inlet will be directed to the outer portion of the rotor blade rows of this stage.
- the two gas flows will be, at least in the early portion of this pumping stage,
- the blades could be adapted so that the inner portion that predominantly pumped the gas received from the higher vacuum stage are angled in a way that suited this gas flow, while the blades at the outer portion are adapted for pumping the gas received at the inter-stage inlet.
- said blades of said inter-stage inlet rotor have a localised change in geometry between said portion adapted for pumping said gas received at said inter-stage inlet and said portion adapted for pumping said gas received at said higher vacuum stage inlet, said localised change in geometry occurring over a length of said rotor blade that is less than 10% of a radius of said rotor blade.
- said length comprising said localised change in geometry is located within a region of said rotor blade that extends for 20% of said radius of said rotor blade towards a centre of said pump from a radial point inside of said inlet aperture by 5% of said aperture length.
- Adapting the blades for the different gas flows means that they will have a localised change of geometry or tilt angle in a region that is between the portion of the blades that predominantly pump one gas flow and the portion that predominantly pumps the other.
- the localised change in geometry or angle will occur across a relatively small region. That is it is located within a length that is less than 10% of the rotor blade radius, this length occurring somewhere in a region running inwardly from a radial position for 20% of the radius of the rotor blade and starting at an outer point that starts at a point that is further towards said outer circumference than an inner edge of the inlet aperture by 5% of the length of the radius of the rotor blade.
- said angle of said outer portion of said blades are adapted for increased pumping speed of said gas received at said inter-stage inlet and an angle of an inner portion are adapted for increased compression of said gas received at an inlet of said higher vacuum stage.
- the angles of the blades on the rotor blade rows may change across the length of the blade depending on whether the pumping speed or compression of the gas is the most important factor.
- the outer portion of the blades may be adapted for increased pumping speed while the inner portion may be adapted for increased pumping compression.
- the outer circumference will be pumping the gas input at the inter-stage inlet and this may require some acceleration while the inner portion will be pumping gas from an upstream inlet and this may require compression more than it requires acceleration.
- an angle between a radial plane, that is a plane perpendicular to an axis of said pump, and an outer section of said blade is greater than an angle between said radial plane and an inner section of said blade.
- the angle of the blade at the outer section is provided for increased pumping speed and thus, generally has more tilt - that is a greater angle between the radial plane and the blade, than the angle of the blade at the inner section which is for providing increased compression. This is different to conventional blades where if there is any change in angle along the length of the blade then generally the outer portion of the blades are flatter to cover the increased area at the outer edge.
- each of said rotor blade rows have multiple blades, said blades of said inter-stage inlet rotor blade row, said inter-stage inlet rotor blade row being said rotor blade row of said lower vacuum stage adjacent to said interstage inlet, having at least some of said blades of a smaller diameter than said larger diameter.
- the length of the rotor blades may also be changed at the rotor blade row adjacent to the inlet. That is some of them may have their rotor tips removed in some cases so that these shortened blades do not extend beyond the inter-stage inlet allowing for a greater inlet area.
- the pump comprises a plurality of stator blade rows, said blades of said inter-stage inlet stator blade row, said inter-stage inlet stator blade row being said stator blade row of said lower vacuum stage adjacent to said interstage inlet, having an angle of an outer portion of said blades adapted for the pumping of gas received at said inter-stage inlet and an angle of an inner portion adapted for the pumping of gas received at an inlet of said higher vacuum stage.
- stator blades may be adapted in this way.
- stators do not rotate providing localised changes in geometry may be more straightforward with a stator and thus, in some
- embodiments may be preferred to changing the rotor geometry.
- said blades of said inter-stage inlet stator have a localised change in geometry between said portion adapted for said gas received at said inter-stage inlet and said portion adapted for said gas received at said upstream inlet, said localised change in geometry occurring over a length of said stator blade that is less than 10% of a radius of said stator blade, said length being in a region of said stator blade that extends for 20% of said radius of said stator blade inwardly from a radial point inside of said inlet aperture by 5% of said aperture length.
- said angle of said outer portion of said blades are adapted for increased pumping speed of said gas received at said inter-stage inlet and an angle of an inner portion are adapted for increased compression of said gas received at an inlet of said higher vacuum stage.
- each of said stator blade rows have multiple blades, said blades of said inter-stage inlet stator blade row, said inter-stage inlet stator blade row being said stator blade row of said lower vacuum stage adjacent to said inter- stage inlet, having an increased number of blades at an outer diameter compared to a number of blades at an inner diameter of said blade row.
- the number of blades towards an outer edge may be different to the number towards the centre, the number being increased towards the outer edge.
- inter-stage inlet rotor blade row and/or stator blade row may be desirable, and in some embodiments further rotor blade and/or stator blade rows may also be adapted in this way, such that the next stator and/or rotor blade row in the downstream direction may be adapted in a similar or the same way as that of the inter-stage inlet rotor and/or stator blade row.
- the inter-stage inlet may be between any of several different stages of the pump, and indeed there may be multiple inter-stage inlets between several different stages, in some embodiments at least one of the inter-stage inlets is between a first high vacuum stage of the pump and a second lower vacuum stage of the pump.
- the first stage of the pump has a diameter that is dependent on the chamber to which it is attached, and this is often governed by a standard.
- the rotor blade rows of subsequent stages are not so limited and may have a larger diameter than the first stage.
- Figure 1 shows a section through a turbomolecular pump with a split flow according to the prior art
- Figure 2 shows a section through a turbomolecular pump with a split flow according to an embodiment
- Figure 3a shows a cross section through an inlet to a turbomolecular pump according to an embodiment
- Figure 3b schematically shows a side view of a rotor blade in the inter-stage rotor blade row
- Figure 4 schematically shows a top view of the rotor blade row
- Figure 5 shows a stator bridge
- Figure 6 shows a view of the turbomolecular pump according to an embodiment
- Figure 7 shows a plurality of chambers being evacuated by a turbomolecular pump according to an embodiment
- a pump comprising a plurality of pumping stages.
- One pumping stage comprises rotor blade rows of a smaller diameter upstream of a pumping stage with rotor blade rows of a larger rotor diameter. This difference in diameters allows the pump to pump "end on" gas admitted at an inter-stage inlet.
- the gas is pumped into the stage with the larger diameter rotor blade rows and directed axially onto the exposed outer edge of rotor blades.
- a special "adapter bridge" may be used between the stator stages for the gas inlet.
- the pump has the benefit of a splitflow pump, providing the gas with access to the turbo section while reducing pump height as the gas for this interstage is entering on the same axis as the rotor rather than in the more conventional radial method.
- Embodiments improve potential pumping performance while using a reduced footprint. This is achieved by using smaller turbo discs in the upper section of the rotor and larger ones below. Such an arrangement is similar to more
- Figure 2 shows the rotor blade rows of a turbomolecular pump according to an embodiment.
- Figure 1 shows a similar view of a conventional turbomolecular pump.
- the inter-stage gas inlet 10 between the two stages is a radial inlet with a radial gas flow which therefore requires a significant gap between the rotor blade rows of the two stages to provide a sufficiently large inlet.
- the gas input at the inter-stage inlet 10 arrives in a radial direction and is diverted by a gas deflection means (not shown) to an axial direction such that it enters the pump as an axial flow above the upper rotor 22a of the second stage.
- the inlet aperture is between the diameter of the rotor blade rows 20 of the first stage and the diameter of the rotor blade rows 22 of the second stage.
- the distance between the first stage with the smaller diameter rotor blade rows and the second stage is considerably smaller in the embodiment of figure 2 when compared to the conventional design of figure 1 .
- a typical distance between the stages of embodiments is a distance that is equal to the distance between adjacent rotor blade rows within a stage or is greater than this but no more than the distance between two rotor blade rows within a stage.
- the larger distance between the stages of the conventional turbomolecular pump shown in Figure 1 is required to provide a sufficient sized inlet for gases entering the pump at this stage.
- the gases in the pump of figure 1 enter via a radial input across the top of the upper rotor of the second stage and are diverted from a radial flow to an axial flow by the rotating rotor blade rows of the pump.
- the input gas is diverted by a gas deflecting means at the input and is input in an axial direction onto the outer tips of the rotor blade rows of the second stage.
- the inlet may be smaller than the inlet of Figure 1 , this is compensated for to some extent by the improved pumping effectiveness that results from the input gas being directed onto the outer edge of the rotor blades that rotate faster than the more central portion of these blades.
- the size of the aperture of the embodiment of Figure 2 is limited by the difference in diameter size of the rotor blade rows of the different stages. In figure 1 the aperture size depends on the distance between the two stages, thus, increasing the aperture size in the pump of Figure 1 increases the length of the pump.
- Figure 3a shows a cross section through the inter-stage inlet 10 of the
- Inlet 10 has flow deflecting portion 12 and aperture 14.
- the flow deflection portion takes the form of an axial ly oriented surface which deflects molecules arriving in a radial direction.
- the aperture 14 lies in the radial plane perpendicular to the axis of the pump and its size is constrained by the difference in diameters of the two rotor blade rows.
- the flow deflecting surface 12 runs parallel to the axis adjacent to the outer circumference of the pumping stage comprising the smaller diameter rotor blade rows.
- aperture 14 is formed within the stator bridge.
- Figure 3b shows a side view of a rotor blade 24 of the inter-stage rotor blade row 22a.
- Rotor blade rows of turbomolecular pump have multiple blades that are angled to drive the molecules of the gas being pumped down through the pump. The larger the angle or greater the tilt of the blade the more gas it will capture and the more speed it will impart thereby increasing pumping speed. The flatter the angle the more compression will be provided by the pump. Owing to the way the gases of the different stages are input to the pump, the gas input to the upstream stage being input across the diameter of the smaller diameter stage, while the gas input at the inter-stage input being input towards an outer edge of the larger diameter stage, the gas from each input have different flows.
- the two flows of gas at least initially travel as almost separate flows, the newly added gas flowing down the outer edge of the pump and the gas being pumped from an earlier stage being towards a radially inner position of the pump.
- This allows the blades of either the rotor or stator or both to be designed to be tilted in a way that imparts the required pumping effect to the different gas flows being pumped by the different portions of the rotor blade rows.
- Figure 3b shows a side view of one such rotor blade 24, the wider section indicating the outer portion with in this case a larger tilt angle.
- the position of inlet aperture 14 is also shown as is the centre axis of the pump C.
- the localised change in geometry occurs over a region RL.
- the length of this region is restricted to 10% or less of the radius R of the blade, and is located somewhere within a region R A , which extends from a point further towards the outer edge of the blade than the inner point of the inlet aperture by 5% of the length of the radius and extends towards a centre of the blade for a length that is 20% or less than the length of the blade.
- the localised change in geometry occurs in a region where the two gas flows from the different inlets are adjacent/coincide with each other.
- the inner section of the blade immediately following the inter-stage inlet will be mainly pumping the gas pumped from the earlier stage while the outer section will be predominantly pumping the gas received at the inter-stage inlet.
- the design is such that the pumping properties of the blades for the gas input at the inter-stage inlet are focussed on capture and acceleration and have a steeper angle of blade.
- the blades towards the inner portion will be flatter to provide good compression of the gas coming from an earlier stage to avoid any backflow of gases.
- the blades will have a twisted nature with a steeper angle towards the outside and a flatter angle towards the inside.
- the change in angle of the blades will result in a localised change in geometry around the point where the two flows change predominance.
- Figure 3b shows a change in angle of rotor blade
- the localised change in geometry is provided by the stator blades, where again the change in angles is designed to account for the pumping properties required by the predominant gas flow.
- rotor and stator blades may vary towards the inter-stage inlet a tapered diameter being provided, such that they are progressively shorter as the blade rows approach the inter-stage inlet.
- Figure 4 shows a view over the inter-stage rotor blade row 22a which illustrates the blade's twisted form, and the change in angle that occurs such that in this embodiment the outer portion of blades are more tilted than the inner portion of the blades.
- FIG. 5 shows a stator bridge 30 according to an embodiment in cross section.
- the stator bridge 30 comprises a ring having an inner ring portion 32 with an inner diameter corresponding to the diameter of the smaller blades 20 and an outer ring portion 34 with a diameter configured to surround the larger diameter rotor blades 22.
- Connecting pieces 33 hold the two rings together, the gaps between these connecting pieces acting as inlet apertures 14.
- Figure 6 shows a view of the turbomolecular pump 5 with the stator bridge 30 of Figure 5 between the two stages shown.
- Figure 7 shows a plurality of chambers to be evacuated by a turbomolecular pump according to an embodiment.
- the plurality of chambers 40, 42 and 44 are of increasingly high vacuum.
- Chamber 40 is evacuated by an initial pump (not shown), while chambers 42 and 44 are evacuated by different stages of turbomolecular pump 5.
- the highest vacuum stage 44 has an inlet connected to the upper end of the turbomolecular pump 5 that is of a standard size.
- Chamber 42 has an inlet connected to the inter-stage inlet 10 of pump 5.
- the inlet 10 comprises an aperture 14 in the transverse plane of the pump and a flow deflecting means 12 in an axial plane perpendicular to a radius of the pump, so that the flow deflecting means is substantially parallel to the pump axis.
- Rotor blade row of second stage adjacent to inter-stage inlet 24 Rotor blade of rotor blade row 22a
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Non-Positive Displacement Air Blowers (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1700992.9A GB2558921B (en) | 2017-01-20 | 2017-01-20 | A multiple stage turbomolecular pump with inter-stage inlet |
PCT/GB2018/050074 WO2018134566A1 (en) | 2017-01-20 | 2018-01-11 | A multiple stage turbomolecular pump with inter-stage inlet |
Publications (1)
Publication Number | Publication Date |
---|---|
EP3571414A1 true EP3571414A1 (en) | 2019-11-27 |
Family
ID=58463032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP18700813.1A Pending EP3571414A1 (en) | 2017-01-20 | 2018-01-11 | A multiple stage turbomolecular pump with inter-stage inlet |
Country Status (6)
Country | Link |
---|---|
US (1) | US20190345948A1 (en) |
EP (1) | EP3571414A1 (en) |
JP (1) | JP2020505546A (en) |
CN (1) | CN110177950B (en) |
GB (1) | GB2558921B (en) |
WO (1) | WO2018134566A1 (en) |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2229724B2 (en) * | 1972-06-19 | 1980-06-04 | Leybold-Heraeus Gmbh, 5000 Koeln | Turbo molecular pump |
GB9725146D0 (en) * | 1997-11-27 | 1998-01-28 | Boc Group Plc | Improvements in vacuum pumps |
US6412173B1 (en) * | 1999-07-26 | 2002-07-02 | Phoenix Analysis And Design Technologies, Inc. | Miniature turbomolecular pump |
US6503050B2 (en) * | 2000-12-18 | 2003-01-07 | Applied Materials Inc. | Turbo-molecular pump having enhanced pumping capacity |
GB0124731D0 (en) * | 2001-10-15 | 2001-12-05 | Boc Group Plc | Vacuum pumps |
DE10353034A1 (en) * | 2003-11-13 | 2005-06-09 | Leybold Vakuum Gmbh | Multi-stage friction vacuum pump |
DE102007027354A1 (en) * | 2007-06-11 | 2008-12-18 | Oerlikon Leybold Vacuum Gmbh | Turbo molecular pump |
DE102009011082A1 (en) * | 2009-02-28 | 2010-09-02 | Oerlikon Leybold Vacuum Gmbh | Multi-inlet vacuum pump |
JP5786639B2 (en) * | 2011-10-24 | 2015-09-30 | 株式会社島津製作所 | Turbo molecular pump |
EP2757266B1 (en) * | 2013-01-22 | 2016-03-16 | Agilent Technologies, Inc. | Rotary vacuum pump |
-
2017
- 2017-01-20 GB GB1700992.9A patent/GB2558921B/en active Active
-
2018
- 2018-01-11 EP EP18700813.1A patent/EP3571414A1/en active Pending
- 2018-01-11 JP JP2019538604A patent/JP2020505546A/en active Pending
- 2018-01-11 WO PCT/GB2018/050074 patent/WO2018134566A1/en unknown
- 2018-01-11 CN CN201880007722.6A patent/CN110177950B/en active Active
- 2018-01-11 US US16/478,741 patent/US20190345948A1/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
CN110177950B (en) | 2021-12-28 |
GB2558921B (en) | 2020-06-17 |
US20190345948A1 (en) | 2019-11-14 |
GB2558921A (en) | 2018-07-25 |
CN110177950A (en) | 2019-08-27 |
WO2018134566A1 (en) | 2018-07-26 |
GB201700992D0 (en) | 2017-03-08 |
JP2020505546A (en) | 2020-02-20 |
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