CN1112649A - A multistage vacuum pump - Google Patents
A multistage vacuum pump Download PDFInfo
- Publication number
- CN1112649A CN1112649A CN95102869A CN95102869A CN1112649A CN 1112649 A CN1112649 A CN 1112649A CN 95102869 A CN95102869 A CN 95102869A CN 95102869 A CN95102869 A CN 95102869A CN 1112649 A CN1112649 A CN 1112649A
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- Prior art keywords
- pump
- pump unit
- unit
- impeller
- roots
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- 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.)
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/08—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by varying the rotational speed
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2/00—Rotary-piston machines or pumps
- F04C2/24—Rotary-piston machines or pumps of counter-engagement type, i.e. the movement of co-operating members at the points of engagement being in opposite directions
- F04C2/28—Rotary-piston machines or pumps of counter-engagement type, i.e. the movement of co-operating members at the points of engagement being in opposite directions of other than internal-axis type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
Abstract
The invention provides a multistage-type vacuum pump having the high ultimate vacuum degree and a little heat quantity generated. A plurality of Roots pumps are provided, and the casings are individually constituted, and respective pump chambers are communicated in series with each other by exhausting pipelines. Driving shafts of rotors of respective Roots pumps are respectively formed, so as to be able to be individually driven by the different rotational numbers.
Description
The present invention relates to a kind of multistage vacuum pump, more particularly, relate to the multistage vacuum pump with some Roots pumps unit, the layout of described Roots pump unit can be adjusted the rotating speed of its impeller separately.
In many systems, all require a vacuum environment, for example in the CVD system, the dry corrosion system, paint finishing etc., it is used for for example semi-conductive production technology.Use vacuum pump to produce a vacuum environment.The oil-tightening rotary vacuum pump of common known usefulness is as being in the vacuum pump that atmospheric pressure carries out start-up function with pump intake.Yet, because this pump uses oil in pump chamber, so the formed vacuum environment of pump may be polluted by oil.So oil-tightening rotary vacuum pump is not suitable in the above-mentioned system.For satisfying above-mentioned requirements, used the vacuum pump of Roots pump recently as a kind of dry seal.In order to obtain high vacuum, some Roots pumps are arranged with polyphone and are formed a multi-stage roots vacuum pump.
In for example Japanese Patent Application NOS.04-8891 and 04-3116096, a kind of common multi-stage roots vacuum pump is disclosed.Wherein, be divided into some pump chambers in the single pump chamber, a pair of impeller is housed in each pump chamber.These impellers are contained in the common active and driven axle, rotate under identical rotating speed.Such pump is called " single-shaft multi-stage vacuum pump " in the following description.
In above-mentioned common single-shaft multi-stage Roots pump, because pump chamber is very near mutually, the heat that produces in pump chamber has a significant impact operation.So pump efficiency descends, and is difficult to temperature is controlled.So, because the rising of temperature may damage initiatively and the shaft sealing of each end of driven axle.Lubricant oil on bearing and the timing gear is sticked in initiatively and on the driven axle and enter pump chamber, and can not use as the dry seal vacuum pump.
In addition, in the single-shaft multi-stage vacuum pump, with a single common axle initiatively and driven axle as each, thus initiatively and driven axle just very long naturally.So when pump worked long hours, because the thermal expansion of axle makes impeller move a sizable scope, especially in the higher low vacuum regions of heat generation rate, this may make impeller contact shell.So, common single-shaft multi-stage vacuum pump in fact can not continuous operation one long-time.
In addition, in common single-shaft multi-stage vacuum pump, connect each exhaust passage and be formed in the housing, and housing is holistic for all pump chambers adjacent pump chamber, as described above.In addition, in order to improve compression ratio, used baroque triplicate blade impeller.In addition, in order to change pump speed at different levels, must change pump chamber size and impeller size at different levels.So pump structure is very complicated, size is big, and cost is very high.As mechanical failure and will be to the pump place under repair time, because it is single shaft and arranges, so must take the entire pump system apart.
In addition, known heat that in Roots pump, produces and inlet pressure, pump speed and compression ratio are proportional.Also known to a relative area of low pressure, even compression ratio is high, can not produce a large amount of heat yet, but then produce a large amount of heat in the high pressure side.Both, in a common single-shaft multi-stage Roots pump, mainly the generation in rear-stage side heat became a problem.
Roots pump also is used for the pressurized machine of motor car engine.In this Roots pump, the double leaf impeller has simple structure,, uses hourglass shape or cocoon shape impeller that is.Its total also is simple, so quality also is stable.We had once carried out an experiment, use the double leaf impeller being arranged and the Roots pump of 300 liters/wheel cylinder volume is arranged during as pressurized machine, how change to check, so obtained result shown in Fig. 1 curve according to the rotating speed of impeller at each pressure span compression ratio.From curve, can know and see that in each pressure span, compression ratio changes according to rotating speed.
The objective of the invention is to overcome the existing problem of above-mentioned common single-shaft multi-stage Roots pump.
An object of the present invention is to provide a multistage vacuum pump, it has improved pump efficiency greatly, be convenient to carry out temperature control, and a high pump speed is provided, and can obtain a high limiting vacuum.
Another object of the present invention provides a multistage vacuum pump, and it produces the heat of a minimum, and energy continuous running one is long-time.
A further object of the present invention provides a multistage vacuum pump, and it is convenient to repair and maintenance operation.
Another purpose of the present invention provides a multistage vacuum pump, and it can make inlet be under the atmospheric pressure and carry out start-up function and obtain a high vacuum, and without any need for additional device.
For achieving the above object, the invention provides a multistage vacuum pump, it comprises some Roots pumps unit, they respectively have a pair of impeller.
There is the shell of each self-forming absolute construction the Roots pump unit.The pump unit is provided with for polyphone, and to adjacent pump unit, the outlet of previous stage pump unit links to each other by the inlet of outlet pipe with one-level pump unit, back for each.The layout of multistage vacuum pump can be adjusted the rotating speed of each pump unit impeller separately, and the impeller at different levels is rotated under required speed.
Interconnective each to adjacent pump unit in, the wheel speed of previous stage pump unit can be set at the wheel speed that is higher than one-level pump unit, back.
Can there be identical pump volume the some pumps unit that is used for multistage vacuum pump.
Impeller can be the double leaf impeller.
Gap between impeller and housing preferably is not more than 0.1mm.
Present invention is described below by embodiment and with reference to accompanying drawing.In the accompanying drawings, identical label is represented identical parts.
Fig. 1 is a plotted curve, has shown in each pressure span medium speed of a bilobed wheel Roots pump and the relation between the compression ratio.
Fig. 2 has schematically shown an embodiment's of multistage vacuum pump of the present invention layout.
Fig. 3 has schematically shown the mode of measuring a limiting vacuum at different levels.
Fig. 4 is a chart, has shown the limiting vacuum that measures at different levels.
Fig. 2 is a schematic representation, has shown the layout of the multistage vacuum pump 1 of one embodiment of the invention.In this embodiment, multistage vacuum pump 1 has 4 Roots pump unit 3,5,7 and 9, and they are provided with for polyphone, form one 4 grades of vacuum pump structures. Roots pump unit 3,5,7 uses identical Roots pump with 9.That is, there is identical pump volume pump unit 3,5,7 and 9.
There is housing 11 each Roots pump unit, and side defines a pump chamber 13 within it.In pump chamber 13, a pair of double leaf impeller (being generally hourglass shape or cocoon shape impeller) 15 and 17 is contained in respectively initiatively and on the driven axle (not shown), is meshing with each other and rotation synchronously with activation.The end of active and driven axle extends into the gear-box (not shown) adjacent to each pump chamber 13.There is timing gear the end of active and driven axle, and it is meshing with each other active and driven axle are rotated synchronously.One belt pulley or other proper device are connected in the other end of driving shaft, so that driving shaft is driven and is rotated by a motor (not shown), impeller 15 and 17 is rotated in mutually opposite direction, shown in arrow among the figure, initiatively and driven axle by machinery or other seal arrangements seal.Because above-mentioned Roots pump structure is known, so be used for the Roots pump of multistage vacuum pump of the present invention this known structure can be arranged, omitted its concrete diagram of arranging and further description at this.
The inlet 19 of first order pump unit 3 links to each other with wanting a rarefied sealing chamber (not shown) by an outlet pipe 35.In the adjacent in pairs pump unit at different levels of back, the outlet of previous stage pump unit links to each other with the inlet of one-level pump unit, back by an outlet pipe 37,39 or 41.The gas that the outlet 33 of fourth stage pump unit 9 will be discharged is put into atmosphere by managing 43.
A heat exchanger 45 is equipped with an oil pump makes the cold oil circulation, shown in dotted arrow among the figure, makes cold oil deliver to the gear-box of pumps at different levels unit with the cooling timing gear.Heat exchanger 45 is provided with cooling water by managing 47, shown in solid arrow among the figure.
In this embodiment, impeller 15 in each the first, the second, third and fourth grade of pump unit 3,5,7 and 9 and 17 rotating speed can be adjusted mutually individually.That is, different with aforesaid common single-shaft multi-stage vacuum pump, active and driven axle in pump unit 3,5,7 and 9 are separate, and can rotate under different rotating speeds.The device of active and driven axle independent rotation can be realized in a different manner.That is, the pump unit in 4 grades 3,5,7 and 9 can be by motor driving separately.Perhaps, use a motor,, the reduction speed ratio that the rotating speed of the pump unit at different levels can be suitable is changed by using belt and the combination of belt pulley or other suitable motion transfering device.Certainly, also can use a gear-box.
In this embodiment, rotating speed is adjusted, and makes the rotating speed of first order pump unit 3 the highest, and reduces with the increase rotating speed of progression.In this case, promptly lower even pump speed raises and a very high compression ratio is provided as previously described in the higher low voltage side heating of degree of vacuum at multistage upstream side, can not produce too big problem.So rotating speed can for example following adjustment: first order pump unit 3 is 3,600rpm; Pump unit, the second level 5 is 1,800rpm; Third level pump unit 7 is 1,170rpm; Fourth stage pump unit 9 is 765rpm; So first order pump speed is adjusted to a very high level, make multistage vacuum pump 1 reach a very high limiting vacuum therefrom.On the other hand, the rotating speed of the fourth stage is adjusted into a lower level, and its compression ratio is adjusted into 2 or lower, and heating is reduced greatly.
In addition, we did an experiment to the Roots pump that uses as pressurized machine, and its pump volume is 300 liters/minute.The first, the second, the Roots pump that uses in third and fourth grade is respectively 3,600rpm, 3,600rpm, 1,800rpm and 1, the 800rpm running, with vacuum gauge 57,59,61,63 and 65 at outlet pipe 35,37,39,41 and 43 place's measuring limit vacuum, as shown in Figure 3.So, obtained the value shown in figure among Fig. 4.Outlet 33 in fourth stage pump unit 9 is under the atmosphere pressure state, and the inlet 19 of first order pump unit 3 can reach 1.4/10
3The high vacuum of torr.When multistage vacuum pump to add level V (though not showing) when operation thereon, can reach 5/10
4The vacuum of torr.
Though in the foregoing embodiments, used Roots pump has same capacity in all grades, can certainly use the Roots pump of different capabilities.Be used for Roots pump of the present invention and be not limited to above-mentioned double leaf wing pump.Can certainly use the Roots pump of three or four impellers.
Under the situation of handling compressible or reactive gas, a device or the valve energy that inert gas is imported pumping system easily is contained on the outlet pipe, rather than is contained on the pump housing.
In addition, it is generally acknowledged that be under the atmospheric pressure with inlet, Roots pump itself can not be found time, and need additional pump or other devices.Yet, verified, the Roots pump of some such multilevel hierarchies is provided, make the gap between impeller and each pump housing be not more than 0.1mm, and as described above, the rotating speed of pumps at different levels is adjusted at a suitable value, even Roots pump has only the double leaf impeller, pump intake is under the atmospheric pressure and carries out start-up function, and reach a high vacuum.
It should be noted that, will be easily if be provided with vacuum gauge in the appropriate location that links to each other with pumps at different levels to measure the resulting vacuum of pump.For example, in the embodiment shown in Figure 2, a vacuum gauge can be located at each on the pipe between the adjacent pump unit, as shown in Figure 3.Like this, when breaking down in when operation system, can find out of order pump unit immediately by the indication of the vacuum gauge that links to each other with the pump unit.For example, the fault if bleed in first order pump unit 5, vacuum gauge 59 will have an indication unusually.In this case, vacuum gauge 57 also can have an indication unusually.
As mentioned above, in the present invention, the wheel speed of the Roots pump unit at different levels can be adjusted separately.So can effectively bleed with the power that is provided to the minimum on the driving shaft in optimum speed running in the pump unit at different levels.So, can improve entire pump efficient, and can increase whole pump speed.In addition, the limiting vacuum of multistage vacuum pump can be brought up to a high level.Particularly, if since compression ratio according to change in rotational speed, pump speed and temperature at different levels are controlled, just can obtain a multistage vacuum pump with very superior pump performance.Just, by in the high vacuum side, promptly in the first order-at this place, even that compression ratio is high its heat generation rate is also lower-increase the rotating speed of pump unit, can obtain a high pump speed and high limiting vacuum.On the other hand, in the rough vacuum side, promptly at rear-stage side, particularly at the easy afterbody of heating, the rotating speed of pump reduces reducing compression ratio, and heating is limited in the considerable scope.So it can eliminate the existing problem of common multistage vacuum pump, for example may make lubricant oil enter the problem of pump chamber owing to the destruction of shaft sealing.Different with the housing of common single-shaft multi-stage vacuum pump, its pump unit housing at all grades is discontinuous mutually, so the pump housing can cool off easily.In this respect, temperature control also is easily.Because can limit heating, so the continuous operation one of pump energy is long-time.
Different with common single-shaft multi-stage vacuum pump, multistage vacuum pump of the present invention does not need to dismantle fully when repairing, and only needs to dismantle the part that will repair.
In addition, because discontinuous Roots pump unit connects by outlet pipe polyphone, it is easy to be provided with an inert gas air feeder, or one with valve compressible or that reactive gas adapts, for it is contained on the pump housing, it needs the processing of complexity so far.Opposite with the common multistage vacuum pump that uses the large-scale integral pump, the present invention is according to the position that will install, by suitably drawing outlet pipe, and can increase the degrees of freedom of pump structure.So it can constitute and is applicable to each special purpose pumping system.
For obtaining different pump performances, common multistage vacuum pump needs bigger design to change.And the present invention can be by changing rotating speed, the pump volume of employed pump unit, or the progression of set pump unit and easily change pump performance.
In addition, because use the pump performance that is easy to the double leaf impeller Roots pump that designs and produce and obtains satisfaction, compare with common multistage vacuum pump, it can provide the multistage vacuum pump of stabilised quality.
By the gap between impeller and the housing being adjusted at 0.1mm or still less, the inlet of pump is under the atmospheric pressure and begins operation and obtain a high vacuum, and not resemble common Roots pump needs one carried wet or other devices.
In addition, by the vacuum gauge that links to each other with pumps at different levels unit is set, when there is fault in system, can find to cause the pump of fault immediately.As mentioned above, multistage vacuum pump of the present invention comprises some Roots pumps unit, and they are driven by discontinuous axle separately.So, when needs are repaired, only need to dismantle and repair the pump unit of out of order that one-level.From the viewpoint of repairing, can find to cause the pump of the system failure immediately, this above-mentioned advantage is very useful.In addition, because multistage vacuum pump of the present invention can have the pump unit of same pump volume to constitute by some, so, if the pump unit that same pump volume is arranged is as spare part, when system breaks down, by using the standby out of order pump of pump unit replacement unit, the work of recovery system immediately simply.
The present invention can have many modification, all among spiritual scope of the present invention.
Claims (6)
1, a kind of multistage vacuum pump comprises:
One group of Roots pump unit, they are connected to form a multilevel hierarchy with polyphone, there is a housing each Roots pump unit, it is formed with the pump chamber of an inlet and an outlet, a pair of impeller that is arranged in the described pump chamber, and it is contained on the corresponding parallel axes, be meshing with each other and rotation synchronously with activation, with a pair of timing gear, it is contained in the corresponding end of the outer described parallel axes of described pump chamber, and it is meshing with each other described a pair of impeller is rotated synchronously; With
Outlet pipe, it makes each be chained together the connection so that the pump chamber of described one group of pump unit is contacted mutually to the outlet of the previous stage pump unit of adjacent Roots pump unit and the inlet of one-level pump unit, back;
Described one group of Roots pump unit housing is separated from each other,
The layout of described multistage vacuum pump can be adjusted the wheel speed of described each pump unit independently.
2, multistage vacuum pump as claimed in claim 1 is characterized in that: interconnective each to adjacent pump unit in, the wheel speed of previous stage pump unit is adjusted into the wheel speed that is higher than one-level pump unit, back.
3, multistage vacuum pump as claimed in claim 2 is characterized in that: there is identical pump volume described one group of pump unit.
4, as arbitrary described multistage vacuum pump among the claim 1-3, it is characterized in that: described paired impeller is the double leaf impeller.
5, multistage vacuum pump as claimed in claim 4 is characterized in that: the gap between described housing and impeller is not more than 0.1mm.
6, as arbitrary described multistage vacuum pump among the claim 1-5, it is characterized in that: comprise the vacuum gauge that links to each other with pumps at different levels unit, in order to measure by the resulting vacuum in described pump unit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP70200/94 | 1994-03-16 | ||
| JP7020094 | 1994-03-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1112649A true CN1112649A (en) | 1995-11-29 |
Family
ID=13424643
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95102869A Pending CN1112649A (en) | 1994-03-16 | 1995-03-15 | A multistage vacuum pump |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0674106A1 (en) |
| KR (1) | KR950033092A (en) |
| CN (1) | CN1112649A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100379894C (en) * | 2001-10-11 | 2008-04-09 | 奥林肯莱博尔德真空技术有限责任公司 | Multi-chamber installation for treating objects under vacuum, method for evacuating said installation and evacuation system therefor |
| CN101213370B (en) * | 2005-07-20 | 2011-05-18 | 阿尔卡特朗讯公司 | Fast energy-saving chamber pumping |
| CN106438365A (en) * | 2015-08-27 | 2017-02-22 | 上海伊莱茨真空技术有限公司 | Modular integrated multi-stage and multi-drive chamber partially non-coaxial dry type vacuum single pump |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000283024A (en) * | 1999-03-30 | 2000-10-10 | Aisin Seiki Co Ltd | Pump device |
| DE10144210A1 (en) * | 2001-09-08 | 2003-03-27 | Sgi Prozess Technik Gmbh | pump system |
| JP3941452B2 (en) * | 2001-10-17 | 2007-07-04 | 株式会社豊田自動織機 | Operation stop control method and operation stop control device for vacuum pump |
| CN109237959A (en) * | 2018-09-07 | 2019-01-18 | 华电电力科学研究院有限公司 | A kind of multi-stage dry Roots vaccum pump double pressure condenser pumped vacuum systems and method |
| CN110360112A (en) * | 2019-05-28 | 2019-10-22 | 上海伊莱茨真空技术有限公司 | A kind of multi-stage roots pump vacuum energy-saving system |
| CN110645176A (en) * | 2019-10-12 | 2020-01-03 | 常州市金坛区维格生物科技有限公司 | Continuous discharging device of vacuum unit |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB809443A (en) * | 1954-02-27 | 1959-02-25 | Heraeus Gmbh W C | Improvements in or relating to rotary high-vacuum pumps |
| US2936107A (en) * | 1956-06-14 | 1960-05-10 | Nat Res Corp | High vacuum device |
| DE3444169A1 (en) * | 1984-12-04 | 1986-06-12 | Loewe Pumpenfabrik GmbH, 2120 Lüneburg | Arrangement for optimising the operation of vacuum pump installations |
| DE9306559U1 (en) * | 1992-06-10 | 1993-07-01 | Siemens AG, 8000 München | Arrangement consisting of at least two liquid ring machines connected in series |
-
1995
- 1995-03-06 EP EP95103183A patent/EP0674106A1/en not_active Withdrawn
- 1995-03-15 CN CN95102869A patent/CN1112649A/en active Pending
- 1995-03-15 KR KR1019950005362A patent/KR950033092A/en not_active Application Discontinuation
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100379894C (en) * | 2001-10-11 | 2008-04-09 | 奥林肯莱博尔德真空技术有限责任公司 | Multi-chamber installation for treating objects under vacuum, method for evacuating said installation and evacuation system therefor |
| CN101213370B (en) * | 2005-07-20 | 2011-05-18 | 阿尔卡特朗讯公司 | Fast energy-saving chamber pumping |
| CN106438365A (en) * | 2015-08-27 | 2017-02-22 | 上海伊莱茨真空技术有限公司 | Modular integrated multi-stage and multi-drive chamber partially non-coaxial dry type vacuum single pump |
| WO2017031807A1 (en) * | 2015-08-27 | 2017-03-02 | 上海伊莱茨真空技术有限公司 | Non-coaxial vacuum pump with multiple driving chambers |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0674106A1 (en) | 1995-09-27 |
| KR950033092A (en) | 1995-12-22 |
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| WD01 | Invention patent application deemed withdrawn after publication |