EP1476661A1 - Vacuum pump - Google Patents

Vacuum pump

Info

Publication number
EP1476661A1
EP1476661A1 EP03702650A EP03702650A EP1476661A1 EP 1476661 A1 EP1476661 A1 EP 1476661A1 EP 03702650 A EP03702650 A EP 03702650A EP 03702650 A EP03702650 A EP 03702650A EP 1476661 A1 EP1476661 A1 EP 1476661A1
Authority
EP
European Patent Office
Prior art keywords
oil
seal
rotor
vacuum pump
bearing
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.)
Granted
Application number
EP03702650A
Other languages
German (de)
French (fr)
Other versions
EP1476661B1 (en
Inventor
Thomas Dreifert
Wolfgang Giebmanns
Hans-Rochus Gross
Hartmut Kriehn
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Leybold GmbH
Original Assignee
Leybold Vakuum GmbH
Leybold Vacuum GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Leybold Vakuum GmbH, Leybold Vacuum GmbH filed Critical Leybold Vakuum GmbH
Publication of EP1476661A1 publication Critical patent/EP1476661A1/en
Application granted granted Critical
Publication of EP1476661B1 publication Critical patent/EP1476661B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • 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
    • F04C27/00—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids
    • F04C27/008—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids for other than working fluid, i.e. the sealing arrangements are not between working chambers of the machine
    • F04C27/009—Shaft sealings specially adapted for pumps
    • 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
    • F04C2220/00—Application
    • F04C2220/40—Pumps with means for venting areas other than the working chamber, e.g. bearings, gear chambers, shaft seals

Definitions

  • the invention relates to a vacuum pump with at least one rotor shaft, which has a rotor section with a rotor, a bearing section with a bearing and a shaft seal arrangement axially between the rotor section and the bearing section.
  • Vacuum pumps of this type can be designed, inter alia, as screw pumps, side channel compressors and root pumps.
  • the vacuum pumps mentioned have in common that they are dry-compressing vacuum pumps with oil or grease lubricated bearings and / or gears. These pumps are generally used to create a pre-vacuum.
  • the task of the sealing arrangement between the actual rotor and the bearing or gearbox is, on the one hand, to avoid gas passage from the rotor section to the bearing section and, on the other hand, to prevent liquid passage from the bearing section into the rotor section.
  • relatively good sealing contact seals can be used, for example in the form of radial shaft seals, slide rings etc.
  • only non-contact shaft seals can be used, which, however, cannot completely exclude leaks due to the design.
  • a known contactless shaft seal arrangement consists of one or more piston sealing rings as a gas seal and an oil splash ring as an oil seal.
  • a reliable and high sealing effect cannot be achieved with this.
  • the gas compressed in the rotor section should not come into contact with the oil from the bearing section, since the oil may be decomposed thereby and thereby lose its lubricity.
  • the escaping oil, gas or gas mixture can also be toxic or explosive and therefore dangerous.
  • the object of the invention is therefore to improve the shaft seal having a gas seal and an oil seal in a vacuum pump.
  • the shaft seal arrangement is designed such that between the rotor-side gas seal and the bearing-side oil seal a separation chamber is provided which surrounds the rotor shaft and is ventilated by at least one separation chamber ventilation duct.
  • the separation chamber is set to a desired gas pressure through the ventilation duct. This ensures that the pressure drop across the gas seal and that across the oil gasket dropping pressure difference can be set.
  • the separation chamber can be subjected to atmospheric gas pressure or the storage-side gas pressure through the ventilation duct, so that the gas pressure in the separation chamber is not below the storage-side gas pressure. This can prevent the oil from migrating from the bearing side through the oil seal towards the separation chamber.
  • the separation chamber gas pressure can be set higher than the gas pressure on the rotor side of the gas seal, so that explosive and / or toxic gases cannot escape from the rotor section through the gas seal.
  • a shaft seal arrangement is realized, which prevents gas from the rotor section into the bearing section and oil from the bearing section into the rotor section in a simple and reliable manner, even in the case of gas and oil seals which are not completely sealed by design. Only a small amount of production and space is required for the separation chamber, so that a compact and effective shaft seal arrangement is realized with little means.
  • the separation chamber ventilation duct opens into the surrounding atmosphere outside the pump. In this way, there is always atmospheric pressure in the separation chamber and the same gas pressure as in the bearing housing, if this is also vented to the environment. The pressure drop across the oil seal is then practically zero, so that due to the lack of pressure difference, no oil is pressed from the bearing section in the direction of the separation chamber or rotor section.
  • the gas seal and the oil seal are each designed as non-contact seals.
  • the shaft seal arrangement can also be vacuum pumps with high speeds and high rotor shaft diameters are used.
  • the gas seal is preferably designed as a gap seal or as a labyrinth seal, with piston rings or with floating sealing rings.
  • the gas seal is a non-contact throttle seal, which reduces the gas passage to an unavoidable minimum.
  • the labyrinth seal of the gas seal preferably has at least one piston ring which projects into an annular groove of the rotor shaft.
  • the piston ring is biased outwards and therefore fixed and stationary on the housing side.
  • the piston ring protrudes into the rotor shaft annular groove, as a result of which a labyrinth-like gap is formed between the piston ring and the annular groove, which acts as a throttle seal.
  • the gas seal can have a plurality of labyrinth seals of this type arranged axially one behind the other.
  • the oil seal on the rotor shaft preferably has an encircling oil centrifugal ring which projects into an annular centrifugal chamber on the housing side, which is connected to an oil return channel to the bearing housing. This creates an effective non-contact oil seal.
  • radial and / or axial non-conical or conical gaps are formed between the oil slinger and the centrifugal chamber walls on the housing.
  • the oil slinger and the opposite fixed walls are designed so that the incoming oil is thrown outwards while the rotor shaft is rotating and the oil that is not thrown off runs down into the return channel.
  • the oil seal on the axial rotor side of the oil centrifugal ring preferably has at least one annular catch chamber with an oil drain channel which opens into the bearing housing.
  • the oil seal therefore consists of two or more centrifugal or trap chambers with an oil drain channel.
  • the oil drainage channels can be combined in a single channel, but each centrifugal or collecting chamber can also be assigned its own separate oil drainage channel. This eliminates mutual malfunctions in the oil drain, so that the sealing effect of the oil seal is only slightly influenced even in the event of malfunctions in an oil drain channel.
  • Each centrifugal or trap chamber of the oil seal is preferably assigned at least one ventilation duct.
  • the ventilation duct can indeed lead outside to the atmosphere, but should preferably lead back to the bearing housing.
  • the centrifugal chambers can be ventilated via a single common ventilation duct or via at least one separate ventilation duct.
  • the ventilation through the ventilation channels ensures that there is no pressure difference within the oil seal, i.e. between the individual centrifugal chambers. A gas flow and thus an entrainment of oil in the direction of the separation chamber or rotor section is practically impossible. The passage of gases from the separation chamber towards the bearing housing is therefore largely prevented.
  • the separation chamber ventilation duct opens in the vicinity of the lowest point of the separation chamber and has a slope, so that any liquid that may escape can run out of the separation chamber. Even if oil or other liquids come from the bearing section or from the If the rotor section should reach the separation chamber, this could run outwards. This ensures that no liquid can collect in the separation chamber.
  • the bearing is preferably axially capped on the rotor side. As a result, a first barrier for oil or other liquids from the bearing is already realized between the bearing and the shaft seal arrangement.
  • a sealing gas source is connected to the separation chamber ventilation duct, through which a sealing gas is introduced into the separation chamber under excess pressure. This is necessary and useful if toxic and / or explosive gases are conveyed in the rotor section.
  • a sealing gas By feeding the separation gas, a small separation gas flow is generated from the separation chamber in the direction of the rotor section. In this way, the escape of gas from the rotor section can be prevented.
  • air or nitrogen can be used as the sealing gas.
  • a sealing gas line from the sealing gas source to the bearing housing or the bearing section can additionally be provided. This ensures that there is no significant pressure drop across the oil seal.
  • the sealing gas has a pressure of 1.3 bar, for example.
  • the rotor shaft is designed as a flying rotor shaft, which is mounted only on the pressure side of the rotor section, on the suction side of the rotor section.
  • Section of the rotor shaft is designed to be bearing-free. In this way, a bearing in the region of larger negative pressures is avoided, so that the shaft seal arrangement on the suction side of the rotor shaft, which is problematic with large pressure differences, is also avoided.
  • flying rotor shafts have a relatively large shaft diameter. It is only through the present shaft seal arrangement and the provision of a separation chamber between the gas seal and the oil seal that the high peripheral speeds associated with large rotor shaft diameters can be sealed without having to accept an unacceptably large leak.
  • FIG. 2 shows the housing of the screw vacuum pump of FIG. 1 in cross section
  • Fig. 3 is a detail of a longitudinal section along the section line X-III of the pump housing of Fig. 2, and
  • Fig. 4 is a longitudinal section of the pump housing of Fig. 2 along the section line X-IV.
  • the in Figs. 1 to 4 shown vacuum pump 10 is a screw vacuum pump for generating a backing vacuum.
  • the vacuum pump 10 is essentially formed by a housing in which two rotor shafts are rotatably mounted, of which only the main rotor shaft 12 is shown in FIGS. 1-4.
  • the Rotor shaft 12 has a rotor section 14 with a helical rotor 16, a bearing section 18 with two roller bearings 20 and axially between the rotor section 14 and the bearing section 18 a section with a shaft seal arrangement 22. No roller bearing is provided on the rotor-side end 24 of the rotor shaft 12.
  • a gas is sucked in at the flying ends of the rotor sections 14 through a suction line (not shown) in order to generate a vacuum in a recipient connected to the suction line.
  • the sucked-in gas is compressed by the interaction of the rotor 16 shown with a second rotor of a second rotor shaft, not shown, toward the pressure side of the rotor section 14 and is discharged there with an atmospheric pressure via a gas outlet, not shown.
  • bearing section 18 of the rotor shaft 12 two roller bearings are provided for rotatable mounting, of which only the roller bearing 20 on the rotor side is shown. Furthermore, the rotor shaft 12 in the bearing section 18 has a gear 26, via which the rotor shaft 12 is driven.
  • the bearing housing interior 30 formed by the bearing housing 28 contains an oil supply for the lubrication and cooling of the roller bearings 20 and the gearwheel (s) 26.
  • the shaft seal arrangement essentially has three axial sections, namely a gas seal 32 on the rotor side, an oil seal 34 on the bearing side and a separating chamber 36 therebetween.
  • the shaft seal arrangement 22 is surrounded by a seal housing 66.
  • the gas seal 32 is formed by three piston rings 38 which are arranged axially one behind the other.
  • the piston rings 38 are prestressed to the outside and are therefore non-positively connected to the fixed housing.
  • the piston rings 38 each engage in an annular groove 40 of the rotor shaft 12, so that the three piston rings 38 in the annular grooves 40 result in a gap running in a longitudinal section in a meandering manner. In this way, a non-contact labyrinth seal is formed, which ensures a satisfactory gas seal at pressure differences of less than 0.5 bar.
  • the oil seal 34 consists of several parts.
  • the bearing-side section of the oil seal 34 has an oil thrower ring 42 on the rotor shaft side, which has a wave-like profile in longitudinal section.
  • This and the corresponding complementary shape of the housing 44 surrounding the oil slinger 42 ensures that the oil coming from the bearing section 18 is thrown outwards by the rotating oil slinger 42 while the rotor shaft 12 is rotating, and is drained downwards by a corresponding fixed groove, from where it has to drain back through an oil return channel 46 into the bearing housing.
  • the oil centrifuge ring 42 is surrounded on the housing side by an annular centrifugal chamber 48, which serves to receive and discharge the oil that is flung outwards by the oil centrifugal ring 42 through the oil return channel 46.
  • the oil seal 34 has on the oil centrifuge ring 42 on the rotor side axially two annular oil catch chambers 50, 52, to each of which a circumferential annular groove 58 is assigned on the rotor shaft side.
  • the oil centrifuge chamber 48 has a larger volume than the two axially adjoining oil trap chambers 50, 52.
  • Both the circular centrifugal chamber 48 and the likewise annular oil trap chambers 50, 52 each have their own ventilation duct 59 near their highest point, each of which leads into the bearing housing 28 in the axial direction.
  • the three ventilation ducts 59 are arranged offset to one another in the circumferential direction.
  • the two oil trapping chambers 50, 52 each have an oil return channel 54, 56 through which oil that has reached this point can possibly flow back into the bearing housing 28.
  • piston rings can also be inserted into the annular grooves 58 of the rotor shaft 12 in order to prevent oil from creeping further axially in the direction of the rotor, without one or both oil-collecting chambers 50, 52.
  • the annular and relatively large-volume separation chamber 36 between the gas seal 32 and the oil seal 34 has a separation chamber ventilation duct 60 near its highest point, through which the separation chamber is ventilated to the environment or through which it is connected to a sealing gas source.
  • the separation chamber ventilation duct 60 has an axial section on the separation chamber side and then at right angles therefrom a radial section which leads to the outside. There is no pressure difference and no oil is pressed through the oil seal by a pressure difference in the direction of the rotor, since the bearing housing is also vented to the environment or because it is also subjected to the same sealing gas pressure as the separation chamber.
  • a further separation chamber ventilation duct 62 is provided, which has a downward slope and opens into a vertical outlet 64.
  • the separation chamber ventilation duct 62 also serves as a drain for If necessary, 01 reached this far, or for liquids from the rotor section.
  • the provision of the separation chamber 36 ensures in a simple and compact manner that fluids can neither get from the rotor section 14 to the bearing section 18 nor from the bearing section 18 to the rotor section 14.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
  • Sealing Devices (AREA)

Abstract

The vacuum pump (10) comprises at least one rotor shaft (12) having a rotor section (14) with a rotor (16), a bearing section (18) with a bearing (20), and a shaft sealing system (22) that is axially situated between the rotor section (14) and the bearing section (18). The shaft sealing system (22) axially comprises, on the side of the rotor, a gas seal (32) and, on the side of the bearing, an oil seal (34). The shaft sealing system (22) additionally comprises, between the gas seal (32) and the oil seal (34), a separating chamber, which surrounds the rotor shaft (12) and is ventilated by at least one separating chamber ventilation duct (60, 62). This enables the pressure differential that decreases via the gas seal and the pressure differential that decreases via the oil seal to be adjusted. An appropriate adjustment can prevent oil on the bearing side from passing through the oil seal toward the separating chamber.

Description

Vakuumpumpe vacuum pump
Die Erfindung bezieht sich auf eine Vakuumpumpe mit mindestens einer Rotorwelle, die einen Rotorabschnitt mit einem Rotor, einen Lagerabschnitt mit einem Lager und axial zwischen dem Rotorabschnitt und dem Lagerabschnitt eine Wellendichtungsanordnung aufweist .The invention relates to a vacuum pump with at least one rotor shaft, which has a rotor section with a rotor, a bearing section with a bearing and a shaft seal arrangement axially between the rotor section and the bearing section.
Derartige Vakuumpumpen können u.a. als Schraubenpumpen, Seiten- kanalverdichter, und Rootspumpen ausgebildet sein. Den genannten Vakuumpumpen ist gemeinsam, dass sie trockenverdichtende Vakuumpumpen mit öl- oder fettgeschmierten Lagern und/oder Getrieben sind. Diese Pumpen werden in der Regel zur Erzeugung von Vorvakuum eingesetzt. Die Aufgabe der Dichtungsanordnung zwischen dem eigentlichen Rotor und dem Lager bzw. Getriebe liegt zum einen in der Vermeidung von Gasdurchtritt von dem Rotorabschnitt zu dem Lagerabschnitt und andererseits in der Vermeidung von Flüssigkeitsdurchtritt von dem Lagerabschnitt in den Rotorabschnitt . Bei niedrigen Rotordrehzahlen und geringen Rotorwellendurchmessern können relativ gut dichtende berührende Dichtungen eingesetzt werden, beispielsweise in Form von Radialwellendichtringen, Gleitringen etc. Bei höheren Drehzahlen und größeren Rotorwellendurchmessern können nur berührungsfreie Wellendichtungen eingesetzt werden, die jedoch konstruktionsbedingt Leckagen nicht völlig ausschließen können .Vacuum pumps of this type can be designed, inter alia, as screw pumps, side channel compressors and root pumps. The vacuum pumps mentioned have in common that they are dry-compressing vacuum pumps with oil or grease lubricated bearings and / or gears. These pumps are generally used to create a pre-vacuum. The task of the sealing arrangement between the actual rotor and the bearing or gearbox is, on the one hand, to avoid gas passage from the rotor section to the bearing section and, on the other hand, to prevent liquid passage from the bearing section into the rotor section. At low rotor speeds and small rotor shaft diameters, relatively good sealing contact seals can be used, for example in the form of radial shaft seals, slide rings etc. At higher speeds and larger rotor shaft diameters, only non-contact shaft seals can be used, which, however, cannot completely exclude leaks due to the design.
Eine bekannte berührungslose Wellendichtungsanordnung besteht aus einem oder mehreren Kolbendichtringen als Gasdichtung und einem Ölspritzring als Öldichtung. Hiermit lässt sich jedoch keine zuverlässige und hohe Dichtungswirkung erzielen. Das in dem Rotorabschnitt verdichtete Gas soll jedoch nicht mit dem Öl aus dem Lagerabschnitt in Verbindung kommen, da das Öl hierdurch ggf. zersetzt werden und seine Schmierfähigkeit hierdurch verlieren kann. Das austretende Öl, Gas oder Gasgemisch kann auch toxisch oder explosiv und daher gefährlich sein.A known contactless shaft seal arrangement consists of one or more piston sealing rings as a gas seal and an oil splash ring as an oil seal. However, a reliable and high sealing effect cannot be achieved with this. However, the gas compressed in the rotor section should not come into contact with the oil from the bearing section, since the oil may be decomposed thereby and thereby lose its lubricity. The escaping oil, gas or gas mixture can also be toxic or explosive and therefore dangerous.
Aufgabe der Erfindung ist es daher, bei einer Vakuumpumpe die eine Gasdichtung und einer Öldichtung aufweisende Wellendichtung zu verbessern.The object of the invention is therefore to improve the shaft seal having a gas seal and an oil seal in a vacuum pump.
Diese Aufgabe wird erfindungsgemäß mit den Merkmalen des Anspruchs 1 gelöst .This object is achieved with the features of claim 1.
Bei der erfindungsgemäßen Vakuumpumpe ist die Wellendichtungsanordnung derart ausgebildet, dass zwischen der rotorseitigen Gasdichtung und der lagerseitigen Öldichtung eine die Rotorwelle umgebende Trennkammer vorgesehen ist, die durch mindestens einen Trennkammer-Lüftungskanal belüftet wird. Durch den Lüftungskanal wird die Trennkammer auf einen gewünschten Gasdruck eingestellt. Hierdurch wird erreicht, dass die über der Gasdichtung abfallende Druckdifferenz und die über der Öl- dichtung abfallende Druckdifferenz eingestellt werden können. So kann die Trennkammer durch den Lüftungskanal beispielsweise mit atmosphärischem Gasdruck oder mit dem lagerseitigen Gasdruck beaufschlagt werden, so dass der Gasdruck in der Trennkammer nicht unter dem lagerseitigen Gasdruck liegt. Hierdurch kann vermieden werden, dass das Öl von der Lagerseite durch die Öldichtung Richtung Trennkammer wandert . Gegenüber dem Gasdruck auf der Rotorseite der Gasdichtung kann der Trennkammer-Gasdruck höher eingestellt sein, so dass explosive und/oder toxische Gase aus dem Rotorabschnitt nicht durch die Gasdichtung entweichen können. Auf diese Weise wird eine Wellendichtungsanordnung realisiert, die auch bei konstruktionsbedingt nicht vollständig dichtenden Gas- und Öldichtungen einen Übertritt von Gas aus dem Rotorabschnitt in den Lagerabschnitt und von Öl aus dem Lagerabschnitt in den Rotorabschnitt auf einfache Weise und zuverlässig verhindert. Für die Trennkammer ist nur ein geringer Herstellungsaufwand und Raumbedarf erforderlich, so dass mit geringen Mitteln eine kompakte und wirkungsvolle Wellendichtungsanordnung realisiert wird.In the vacuum pump according to the invention, the shaft seal arrangement is designed such that between the rotor-side gas seal and the bearing-side oil seal a separation chamber is provided which surrounds the rotor shaft and is ventilated by at least one separation chamber ventilation duct. The separation chamber is set to a desired gas pressure through the ventilation duct. This ensures that the pressure drop across the gas seal and that across the oil gasket dropping pressure difference can be set. For example, the separation chamber can be subjected to atmospheric gas pressure or the storage-side gas pressure through the ventilation duct, so that the gas pressure in the separation chamber is not below the storage-side gas pressure. This can prevent the oil from migrating from the bearing side through the oil seal towards the separation chamber. The separation chamber gas pressure can be set higher than the gas pressure on the rotor side of the gas seal, so that explosive and / or toxic gases cannot escape from the rotor section through the gas seal. In this way, a shaft seal arrangement is realized, which prevents gas from the rotor section into the bearing section and oil from the bearing section into the rotor section in a simple and reliable manner, even in the case of gas and oil seals which are not completely sealed by design. Only a small amount of production and space is required for the separation chamber, so that a compact and effective shaft seal arrangement is realized with little means.
Gemäß einer bevorzugten Ausgestaltung mündet der Trennkammer- Lüf ungskanal außerhalb der Pumpe in die umgebende Atmosphäre. Auf diese Weise herrscht in der Trennkammer stets Atmosphärendruck und der gleiche Gasdruck wie in dem Lagergehäuse, wenn dieses ebenfalls zur Umgebung entlüftet wird. Das Druckgefälle über der Öldichtung ist dann praktisch gleich Null, so dass wegen fehlender Druckdifferenz auch kein Öl von dem Lagerabschnitt in Richtung Trennkammer bzw. Rotorabschnitt gepresst wird.According to a preferred embodiment, the separation chamber ventilation duct opens into the surrounding atmosphere outside the pump. In this way, there is always atmospheric pressure in the separation chamber and the same gas pressure as in the bearing housing, if this is also vented to the environment. The pressure drop across the oil seal is then practically zero, so that due to the lack of pressure difference, no oil is pressed from the bearing section in the direction of the separation chamber or rotor section.
Gemäß einer bevorzugten Ausgestaltung sind die Gasdichtung und die Öldichtung jeweils als berührungsfreie Dichtungen ausgebildet. Hierdurch kann die Wellendichtungsanordnung auch in Va- kuumpumpen mit hohen Drehzahlen und hohen Rotorwellendurchmessern eingesetzt werden.According to a preferred embodiment, the gas seal and the oil seal are each designed as non-contact seals. As a result, the shaft seal arrangement can also be vacuum pumps with high speeds and high rotor shaft diameters are used.
Vorzugsweise ist die Gasdichtung als Spaltdichtung oder als Labyrinthdichtung, mit Kolbenringen oder mit schwimmenden Dichtringen ausgebildet. Die Gasdichtung ist in jedem Fall eine berührungsfreie Drosseldichtung, durch die der Gasdurchtritt auf ein unvermeidbares Minimum reduziert wird.The gas seal is preferably designed as a gap seal or as a labyrinth seal, with piston rings or with floating sealing rings. In any case, the gas seal is a non-contact throttle seal, which reduces the gas passage to an unavoidable minimum.
Vorzugsweise weist die Labyrinthdichtung der Gasdichtung mindestens einen Kolbenring auf, der in eine Ringnut der Rotorwelle hineinragt. Der Kolbenring ist nach außen vorgespannt und daher gehäuseseitig fixiert und feststehend. Der Kolbenring ragt in die Rotorwellen-Ringnut hinein, wodurch zwischen dem Kolbenring und der Ringnut ein labyrinthartig verlaufender Spalt gebildet wird, der als Drosseldichtung wirkt. Die Gasdichtung kann mehrere axial hintereinander angeordnete derartige Labyrinthdichtungen aufweisen.The labyrinth seal of the gas seal preferably has at least one piston ring which projects into an annular groove of the rotor shaft. The piston ring is biased outwards and therefore fixed and stationary on the housing side. The piston ring protrudes into the rotor shaft annular groove, as a result of which a labyrinth-like gap is formed between the piston ring and the annular groove, which acts as a throttle seal. The gas seal can have a plurality of labyrinth seals of this type arranged axially one behind the other.
Vorzugsweise weist die Öldichtung auf der Rotorwelle einen umlaufenden Ölschleuderring auf, der in eine gehäuseseitige ringförmige Schleuderkammer hineinragt, die an einen Ölrücklauf- kanal zu dem Lagergehäuse angeschlossen ist. Auf diese Weise wird eine effektive berührungsfreie Öldichtung geschaffen.The oil seal on the rotor shaft preferably has an encircling oil centrifugal ring which projects into an annular centrifugal chamber on the housing side, which is connected to an oil return channel to the bearing housing. This creates an effective non-contact oil seal.
Gemäß einer bevorzugten Ausgestaltung sind zwischen dem Ölschleuderring und den gehäuseseitigen Schleuderkammerwänden radiale und/oder axiale nicht -konische oder konische Spalte gebildet. Der Ölschleuderring und die gegenüberliegenden feststehenden Wände sind so ausgebildet, dass das eintretende Öl bei rotierender Rotorwelle nach außen abgeschleudert wird und das nicht abgeschleuderte Öl nach unten in den Rücklaufkanal abläuft . Vorzugsweise weist die Öldichtung axialrotorseitig des Öl- schleuderrings mindestens eine ringförmige Fangkammer mit einem Ölablaufkanal auf, der in das Lagergehäuse mündet. Die Öldichtung besteht also aus zwei oder mehr axial hintereinander- liegenden Schleuder- bzw. Fangkammern mit einem Ölablaufkanal. Die Ölablaufkanäle können in einem einzigen Kanal zusammenge- fasst sein, es kann jedoch auch jeder Schleuder- bzw. Fangkammer ein eigener getrennter Ölablaufkanal zugeordnet sein. Hierdurch werden gegenseitige Störungen beim Ölablauf ausgeschlossen, so dass die Öldichtung auch bei Störungen in einem Ölablaufkanal in ihrer Dichtungswirkung nur geringfügig beeinflusst wird.According to a preferred embodiment, radial and / or axial non-conical or conical gaps are formed between the oil slinger and the centrifugal chamber walls on the housing. The oil slinger and the opposite fixed walls are designed so that the incoming oil is thrown outwards while the rotor shaft is rotating and the oil that is not thrown off runs down into the return channel. The oil seal on the axial rotor side of the oil centrifugal ring preferably has at least one annular catch chamber with an oil drain channel which opens into the bearing housing. The oil seal therefore consists of two or more centrifugal or trap chambers with an oil drain channel. The oil drainage channels can be combined in a single channel, but each centrifugal or collecting chamber can also be assigned its own separate oil drainage channel. This eliminates mutual malfunctions in the oil drain, so that the sealing effect of the oil seal is only slightly influenced even in the event of malfunctions in an oil drain channel.
Vorzugsweise ist jeder Schleuder- bzw. Fangkammer der Öldichtung mindestens ein Lüftungskanal zugeordnet . Der Lüftungskanal kann zwar nach außen zur Atmosphäre sollte aber vorzugsweise zum Lagergehäuse zurück geführt sein. Die Schleuderkammern können über einen einzigen gemeinsamen Lüftungskanal, oder aber über jeweils mindestens einen eigenen Lüftungskanal belüftet werden. Durch die Belüftung durch die Belüftungskanäle wird sichergestellt, dass sich auch innerhalb der Öldichtung, also zwischen den einzelnen Schleuderkammern keine Druckdifferenz bildet. Eine Gasströmung und damit eine Mitnahme von Öl in Richtung Trennkammer bzw. Rotorabschnitt ist damit praktisch ausgeschlossen. Auch der Übertritt von Gasen aus der Trennkammer in Richtung Lagergehäuse wird daher weitgehend unterbunden.Each centrifugal or trap chamber of the oil seal is preferably assigned at least one ventilation duct. The ventilation duct can indeed lead outside to the atmosphere, but should preferably lead back to the bearing housing. The centrifugal chambers can be ventilated via a single common ventilation duct or via at least one separate ventilation duct. The ventilation through the ventilation channels ensures that there is no pressure difference within the oil seal, i.e. between the individual centrifugal chambers. A gas flow and thus an entrainment of oil in the direction of the separation chamber or rotor section is practically impossible. The passage of gases from the separation chamber towards the bearing housing is therefore largely prevented.
Gemäß einer bevorzugten Ausgestaltung mündet der Trennkammer- Lüftungskanal in der Nähe vom tiefsten Punkt der Trennkammer und weist ein Gefälle auf, so dass eine eventuell austretende Flüssigkeit aus der Trennkammer ablaufen kann. Selbst wenn Öl oder andere Flüssigkeiten aus dem Lagerabschnitt oder aus dem Rotorabschnitt bis zur Trennkammer gelangen sollten, könnte diese nach außen ablaufen. Hierdurch wird sichergestellt, dass sich keine Flüssigkeit in der Trennkammer ansammeln kann.According to a preferred embodiment, the separation chamber ventilation duct opens in the vicinity of the lowest point of the separation chamber and has a slope, so that any liquid that may escape can run out of the separation chamber. Even if oil or other liquids come from the bearing section or from the If the rotor section should reach the separation chamber, this could run outwards. This ensures that no liquid can collect in the separation chamber.
Vorzugsweise ist das Lager axial rotorseitig gedeckelt ausgebildet. Hierdurch wird bereits zwischen dem Lager und der Wellendichtungsanordnung eine erste Barriere für Öl bzw. andere Flüssigkeiten aus dem Lager realisiert.The bearing is preferably axially capped on the rotor side. As a result, a first barrier for oil or other liquids from the bearing is already realized between the bearing and the shaft seal arrangement.
Gemäß einer bevorzugten Ausgestaltung ist an den Trennkammer- Lüftungskanal eine Sperrgasquelle angeschlossen, durch die unter Überdruck ein Sperrgas in die Trennkammer eingeleitet wird. Dies ist dann erforderlich und sinnvoll wenn in dem Rotorabschnitt giftige und/oder explosive Gase gefördert werden. Durch die Einspeisung des Trenngases wird ein kleiner Trenngasstrom von der Trennkammer in Richtung Rotorabschnitt erzeugt. Auf diese Weise kann der Austritt von Gas aus dem Rotorabschnitt verhindert werden. Als Sperrgas können beispielsweise Luft oder Stickstoff verwendet werden. Durch die Einspeisung von Sperrgas in die Trennkammer wird der Trennkammerdruck gegenüber dem Druck in dem Lagerabschnitt bzw. Lagergehäuse erhöht.According to a preferred embodiment, a sealing gas source is connected to the separation chamber ventilation duct, through which a sealing gas is introduced into the separation chamber under excess pressure. This is necessary and useful if toxic and / or explosive gases are conveyed in the rotor section. By feeding the separation gas, a small separation gas flow is generated from the separation chamber in the direction of the rotor section. In this way, the escape of gas from the rotor section can be prevented. For example, air or nitrogen can be used as the sealing gas. By feeding sealing gas into the separation chamber, the separation chamber pressure is increased compared to the pressure in the bearing section or bearing housing.
Zur Vermeidung jeder Druckdifferenz zwischen dem Lagerabschnitt und der Trennkammer kann zusätzlich eine Sperrgasleitung von der Sperrgasquelle zu dem Lagergehäuse bzw. dem Lagerabschnitt vorgesehen sein. Auf diese Weise wird sichergestellt, dass über der Öldichtung kein nennenswertes Druckgefälle entsteht. Das Sperrgas hat einen Druck von beispielsweise 1,3 bar.To avoid any pressure difference between the bearing section and the separation chamber, a sealing gas line from the sealing gas source to the bearing housing or the bearing section can additionally be provided. This ensures that there is no significant pressure drop across the oil seal. The sealing gas has a pressure of 1.3 bar, for example.
Gemäß einer bevorzugten Ausgestaltung ist die Rotorwelle als fliegende Rotorwelle ausgebildet, die nur an der Druckseite des Rotorabschnittes gelagert ist, an der Saugseite des Rotorab- Schnittes der Rotorwelle jedoch lagerfrei ausgebildet ist. Auf diese Weise wird ein Lager im Bereich größerer Unterdrücke vermieden, so dass auch die bei großen Druckunterschieden problematische Wellendichtungsanordnung auf der Saugseite der Rotorwelle vermieden wird. Fliegende Rotorwellen weisen aus Stabilitätsgründen einen relativ großen Wellendurchmesser auf. Erst durch die vorliegende Wellendichtungsanordnung und das Vorsehen einer Trennkammer zwischen der Gasdichtung und der Öldichtung können die mit großen Rotorwellendurchmessern verbundenen hohen Umfangsgeschwindigkeiten abgedichtet werden, ohne eine unzumutbar große Leckage in Kauf nehmen müssen.According to a preferred embodiment, the rotor shaft is designed as a flying rotor shaft, which is mounted only on the pressure side of the rotor section, on the suction side of the rotor section. Section of the rotor shaft, however, is designed to be bearing-free. In this way, a bearing in the region of larger negative pressures is avoided, so that the shaft seal arrangement on the suction side of the rotor shaft, which is problematic with large pressure differences, is also avoided. For reasons of stability, flying rotor shafts have a relatively large shaft diameter. It is only through the present shaft seal arrangement and the provision of a separation chamber between the gas seal and the oil seal that the high peripheral speeds associated with large rotor shaft diameters can be sealed without having to accept an unacceptably large leak.
Im folgenden wird unter Bezugnahme auf die Zeichnungen ein Aus- führungsbeispiel der Erfindung näher erläutert .An exemplary embodiment of the invention is explained in more detail below with reference to the drawings.
Es zeigen:Show it:
Fig. 1 eine Vakuum-Schraubenpumpe im Längsschnitt,1 is a vacuum screw pump in longitudinal section,
Fig. 2 das Gehäuse der Schraubenvakuumpumpe der Fig. 1 im Querschnitt ,2 shows the housing of the screw vacuum pump of FIG. 1 in cross section,
Fig. 3 ein Ausschnitt eines Längsschnittes entlang der Schnittlinie X-III des Pumpengehäuses der Fig. 2, undFig. 3 is a detail of a longitudinal section along the section line X-III of the pump housing of Fig. 2, and
Fig. 4 einen Längsschnitt des Pumpengehäuses der Fig. 2 entlang der Schnittlinie X-IV.Fig. 4 is a longitudinal section of the pump housing of Fig. 2 along the section line X-IV.
Die in den Fign. 1 bis 4 dargestellte Vakuumpumpe 10 ist eine Schraubenvakuumpumpe zur Erzeugung eines Vorvakuums. Die Vakuumpumpe 10 wird im Wesentlichen von einem Gehäuse gebildet, in dem zwei Rotorwellen drehbar gelagert sind, von denen in den Figuren 1-4 nur die Hauptrotorwelle 12 dargestellt ist. Die Rotorwelle 12 weist einen Rotorabschnitt 14 mit einem schraubenförmigen Rotor 16, einen Lagerabschnitt 18 mit zwei Wälzlagern 20 und axial zwischen dem Rotorabschnitt 14 und dem Lagerabschnitt 18 einen Abschnitt mit einer Wellendichtungsanordnung 22 auf. An dem rotorseitigen Ende 24 der Rotorwelle 12 ist kein Wälzlager vorgesehen.The in Figs. 1 to 4 shown vacuum pump 10 is a screw vacuum pump for generating a backing vacuum. The vacuum pump 10 is essentially formed by a housing in which two rotor shafts are rotatably mounted, of which only the main rotor shaft 12 is shown in FIGS. 1-4. The Rotor shaft 12 has a rotor section 14 with a helical rotor 16, a bearing section 18 with two roller bearings 20 and axially between the rotor section 14 and the bearing section 18 a section with a shaft seal arrangement 22. No roller bearing is provided on the rotor-side end 24 of the rotor shaft 12.
Durch die Drehung der schraubenförmigen Rotoren wird an deren fliegenden Enden der Rotorabschnitte 14 ein Gas durch eine nichtdargestellte Ansaugleitung angesaugt, um auf diese Weise in einem an die Ansaugleitung angeschlossenen Rezipienten einen Unterdruck zu erzeugen. Das angesaugte Gas wird durch Zusammenwirken des dargestellten Rotors 16 mit einem zweiten Rotor einer zweiten nicht dargestellten Rotorwelle zur Druckseite des Rotorabschnittes 14 hin verdichtet und dort mit ungefähr atmosphärischem Druck über einen nicht dargestellten Gasauslass abgeführt .As a result of the rotation of the helical rotors, a gas is sucked in at the flying ends of the rotor sections 14 through a suction line (not shown) in order to generate a vacuum in a recipient connected to the suction line. The sucked-in gas is compressed by the interaction of the rotor 16 shown with a second rotor of a second rotor shaft, not shown, toward the pressure side of the rotor section 14 and is discharged there with an atmospheric pressure via a gas outlet, not shown.
In dem Lagerabschnitt 18 der Rotorwelle 12 sind zur drehbaren Lagerung zwei Wälzlager vorgesehen, von denen nur das rotor- seitige Wälzlager 20 dargestellt ist. Ferner weist die Rotorwelle 12 in dem Lagerabschnitt 18 ein Zahnrad 26 auf, über das die Rotorwelle 12 angetrieben wird. Zur Schmierung und zur Kühlung der Wälzlager 20 und des bzw. der Zahnräder 26 enthält der von dem Lagergehäuse 28 gebildete Lagergehäuseinnenraum 30 einen Ölvorrat .In the bearing section 18 of the rotor shaft 12, two roller bearings are provided for rotatable mounting, of which only the roller bearing 20 on the rotor side is shown. Furthermore, the rotor shaft 12 in the bearing section 18 has a gear 26, via which the rotor shaft 12 is driven. The bearing housing interior 30 formed by the bearing housing 28 contains an oil supply for the lubrication and cooling of the roller bearings 20 and the gearwheel (s) 26.
Die Wellendichtungsanordnung weist im Wesentlichen drei axiale Abschnitte auf, nämlich rotorseitig eine Gasdichtung 32, lager- seitig eine Öldichtung 34 und dazwischen eine Trennkammer 36. Die Wellendichtungsanordnung 22 wird von einem Dichtungsgehäuse 66 umgeben. Die Gasdichtung 32 wird von drei Kolbenringen 38 gebildet, die axial hintereinanderliegend angeordnet sind. Die Kolbenringe 38 sind nach außen vorgespannt und daher kraftschlüssig mit dem feststehenden Gehäuse verbunden. Die Kolbenringe 38 greifen jeweils in eine Ringnut 40 der Rotorwelle 12 ein, so dass sich durch die drei Kolbenringe 38 in den Ringnuten 40 ein im Längsschnitt mäanderartig verlaufender Spalt ergibt. Auf diese Weise ist eine berührungsfreie Labyrinthdichtung gebildet, die bei Druckdifferenzen von weniger als 0,5 bar eine zufriedenstellende Gasabdichtung gewährleistet.The shaft seal arrangement essentially has three axial sections, namely a gas seal 32 on the rotor side, an oil seal 34 on the bearing side and a separating chamber 36 therebetween. The shaft seal arrangement 22 is surrounded by a seal housing 66. The gas seal 32 is formed by three piston rings 38 which are arranged axially one behind the other. The piston rings 38 are prestressed to the outside and are therefore non-positively connected to the fixed housing. The piston rings 38 each engage in an annular groove 40 of the rotor shaft 12, so that the three piston rings 38 in the annular grooves 40 result in a gap running in a longitudinal section in a meandering manner. In this way, a non-contact labyrinth seal is formed, which ensures a satisfactory gas seal at pressure differences of less than 0.5 bar.
Die Öldichtung 34 besteht aus mehreren Teilen. Der lagerseitige Abschnitt der Öldichtung 34 weist rotorwellenseitig einen Ölschleuderring 42 auf, der im Längsschnitt ein wellenartiges Profil aufweist. Hierdurch und durch entsprechend komplementäre Ausformung des den Ölschleuderring 42 umgebenden Gehäuses 44 wird sichergestellt, dass das Öl aus dem Lagerabschnitt 18 kommend bei rotierender Rotorwelle 12 durch den rotierenden Ölschleuderring 42 nach außen abgeschleudert wird, und durch eine entsprechende feststehende Rinne nach unten abgeleitet wird, von wo aus es durch einen Ölrücklaufkanal 46 zurück in das Lagergehäuse ablaufen muss. Der Ölschleuderring 42 ist gehäuse- seitig von einer ringförmigen Schleuderkammer 48 umgeben, die der Aufnahme und Ableitung des von dem Ölschleuderring 42 nach außen geschleuderten Öles durch den Ölrücklaufkanal 46 dient. Die Öldichtung 34 weist an den Ölschleuderring 42 axial rotor- seitig anschließend zwei ringförmige Öl -Fangkammern 50,52 auf, denen rotorwellenseitig jeweils eine umlaufende Ringnut 58 zugeordnet ist. Die Olschleuderkammer 48 hat ein größeres Volumen als die beiden sich axial anschließenden Öl -Fangkammern 50,52. Sowohl die ringförmig umlaufende Schleuderkammer 48 als auch die ebenfalls ringförmig ausgebildeten Öl -Fangkammern 50,52 weisen in der Nähe ihres höchsten Punkts jeweils einen eigenen Lüf ungskanal 59 auf, der in axialer Richtung jeweils in das Lagergehäuse 28 führt. Die drei Lüftungskanäle 59 sind in Um- fangsrichtung versetzt zueinander angeordnet. Die beiden Öl- Fangkammern 50,52 weisen in der Nähe ihres tiefsten Punkts jeweils einen Öl-Rücklaufkanal 54,56 auf, durch den bis hierhin gelangtes Öl ggf. in das Lagergehäuse 28 zurückfließen kann. Alternativ können unter Verzicht auf eine oder auch beide Öl- fangkammern 50,52 in die ringförmigen Nuten 58 der Rotorwelle 12 auch Kolbenringe eingesetzt sein, um ein Weiterkriechen von Öl axial in Richtung Rotor zu verhindern.The oil seal 34 consists of several parts. The bearing-side section of the oil seal 34 has an oil thrower ring 42 on the rotor shaft side, which has a wave-like profile in longitudinal section. This and the corresponding complementary shape of the housing 44 surrounding the oil slinger 42 ensures that the oil coming from the bearing section 18 is thrown outwards by the rotating oil slinger 42 while the rotor shaft 12 is rotating, and is drained downwards by a corresponding fixed groove, from where it has to drain back through an oil return channel 46 into the bearing housing. The oil centrifuge ring 42 is surrounded on the housing side by an annular centrifugal chamber 48, which serves to receive and discharge the oil that is flung outwards by the oil centrifugal ring 42 through the oil return channel 46. The oil seal 34 has on the oil centrifuge ring 42 on the rotor side axially two annular oil catch chambers 50, 52, to each of which a circumferential annular groove 58 is assigned on the rotor shaft side. The oil centrifuge chamber 48 has a larger volume than the two axially adjoining oil trap chambers 50, 52. Both the circular centrifugal chamber 48 and the likewise annular oil trap chambers 50, 52 each have their own ventilation duct 59 near their highest point, each of which leads into the bearing housing 28 in the axial direction. The three ventilation ducts 59 are arranged offset to one another in the circumferential direction. In the vicinity of their lowest point, the two oil trapping chambers 50, 52 each have an oil return channel 54, 56 through which oil that has reached this point can possibly flow back into the bearing housing 28. Alternatively, piston rings can also be inserted into the annular grooves 58 of the rotor shaft 12 in order to prevent oil from creeping further axially in the direction of the rotor, without one or both oil-collecting chambers 50, 52.
Die ringförmige und relativ großvolumige Trennkammer 36 zwischen der Gasdichtung 32 und der Öldichtung 34 weist in der Nähe ihres höchsten Punktes einen Trennkammer-Lüftungskanal 60 auf, durch den die Trennkammer zur Umgebung belüftet wird oder durch den sie mit einer Sperrgasquelle verbunden ist. Der Trennkammer-Lüftungskanal 60 weist trennkammerseitig einen axialen Abschnitt und rechtwinklig davon anschließend einen radialen Abschnitt auf, der zur Außenseite führt. Es herrscht keine Druckdifferenz und kein Öl wird durch eine Druckdifferenz in Richtung Rotor durch die Öldichtung gepresst, da auch das Lagergehäuse zur Umgebung belüftet ist bzw. da es ebenfalls mit dem gleichen Sperrgasdruck wie die Trennkammer beaufschlagt wird.The annular and relatively large-volume separation chamber 36 between the gas seal 32 and the oil seal 34 has a separation chamber ventilation duct 60 near its highest point, through which the separation chamber is ventilated to the environment or through which it is connected to a sealing gas source. The separation chamber ventilation duct 60 has an axial section on the separation chamber side and then at right angles therefrom a radial section which leads to the outside. There is no pressure difference and no oil is pressed through the oil seal by a pressure difference in the direction of the rotor, since the bearing housing is also vented to the environment or because it is also subjected to the same sealing gas pressure as the separation chamber.
In der Nähe des tiefsten Punkt der Trennkammer 36 ist ein weiterer Trennkammer-Lüftungskanal 62 vorgesehen, der ein Gefälle nach unten aufweist und in einem vertikalen Ablauf 64 mündet. Der Trennkammer-Lüftungskanal 62 dient auch als Ablauf für ge- gebenenfalls bis hierher gelangtes 01, bzw. für Flüssigkeiten aus dem Rotorabschnitt .In the vicinity of the lowest point of the separation chamber 36, a further separation chamber ventilation duct 62 is provided, which has a downward slope and opens into a vertical outlet 64. The separation chamber ventilation duct 62 also serves as a drain for If necessary, 01 reached this far, or for liquids from the rotor section.
Durch das Vorsehen der Trennkammer 36 wird auf einfache und kompakte Weise sichergestellt, dass Fluide weder vom dem Rotorabschnitt 14 zu dem Lagerabschnitt 18 noch von dem Lagerabschnitt 18 zu dem Rotorabschnitt 14 gelangen können. The provision of the separation chamber 36 ensures in a simple and compact manner that fluids can neither get from the rotor section 14 to the bearing section 18 nor from the bearing section 18 to the rotor section 14.

Claims

PATENANSPRUCHE PATE CLAIMS
1. Vakuumpumpe mit mindestens einer Rotorwelle (12), die einen Rotorabschnitt (14) mit einem Rotor (16) , einen Lagerabschnitt (18) mit einem Lager (20) und axial zwischen dem Rotorabschnitt (14) und dem Lagerabschnitt (18) eine Wellendichtungsanordnung (22) aufweist,1. Vacuum pump with at least one rotor shaft (12), which has a rotor section (14) with a rotor (16), a bearing section (18) with a bearing (20) and axially between the rotor section (14) and the bearing section (18) Shaft seal arrangement (22),
wobei die Wellendichtungsanordnung (22) axial rotorseitig eine Gasdichtung (32) und axial lagerseitig eine Öldichtung (34) aufweist,wherein the shaft seal arrangement (22) has a gas seal (32) on the axial rotor side and an oil seal (34) on the axial bearing side,
d a d u r c h g e k e n n z e i c h n e t ,characterized ,
dass die Wellendichtungsanordnung (22) zwischen der Gasdichtung (32) und der Öldichtung (34) eine die Rotorwelle (12) umgebene Trennkammer (36) aufweist, die durch mindestens einen Trennkammer-Lüftungskanal (60,62) belüftet wird.that the shaft seal arrangement (22) between the gas seal (32) and the oil seal (34) has a separation chamber (36) surrounding the rotor shaft (12), which is ventilated by at least one separation chamber ventilation duct (60, 62).
2. Vakuumpumpe nach Anspruch 1, dadurch gekennzeichnet, dass der Trennkammer-Lüftungskanal (60,62) nach außen in die umgebende Atmosphäre geführt ist .2. Vacuum pump according to claim 1, characterized in that the separation chamber ventilation duct (60,62) is guided to the outside into the surrounding atmosphere.
3. Vakuumpumpe nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die Gasdichtung (32) und die Öldichtung (34) als berührungsfreie Dichtungen ausgebildet sind.3. Vacuum pump according to claim 1 or 2, characterized in that the gas seal (32) and the oil seal (34) are designed as non-contact seals.
4. Vakuumpumpe nach einem der Ansprüche 1-3, dadurch gekennzeichnet, dass die Gasdichtung (32) als Spaltdichtung oder als Labyrinthdichtung ausgebildet ist. 4. Vacuum pump according to one of claims 1-3, characterized in that the gas seal (32) is designed as a gap seal or as a labyrinth seal.
5. Vakuumpumpe nach Anspruch 4, dadurch gekennzeichnet, dass die Labyrinthdichtung mindestens einen Kolbenring (38) aufweist, der in eine Ringnut (40) der Rotorwelle (12) hineinragt.5. Vacuum pump according to claim 4, characterized in that the labyrinth seal has at least one piston ring (38) which projects into an annular groove (40) of the rotor shaft (12).
6. Vakuumpumpe nach einem der Ansprüche 1-5, dadurch gekennzeichnet, dass die Öldichtung (34) an der Rotorwelle (12) einen umlaufenden Ölschleuderring (42) aufweist, der in eine gehäuseseitige ringförmige Schleuderkammer (48) hineinragt, die an einen Ölrücklaufkanal (46) zu dem Lagergehäuse (28) angeschlossen ist.6. Vacuum pump according to one of claims 1-5, characterized in that the oil seal (34) on the rotor shaft (12) has a circumferential oil slinger (42) which projects into an annular centrifugal chamber (48) on the housing side, which on an oil return channel ( 46) is connected to the bearing housing (28).
7. Vakuumpumpe nach einem der Ansprüche 1-6, dadurch gekennzeichnet, dass zwischen dem Ölschleuderring (42) und den gehäuseseitigen Schleuderkammerwänden radiale oder axiale konische oder nicht-konische Spalte vorgesehen sind.7. Vacuum pump according to one of claims 1-6, characterized in that radial or axial conical or non-conical gaps are provided between the oil slinger (42) and the housing-side centrifugal chamber walls.
8. Vakuumpumpe nach einem der Ansprüche 1-7, dadurch gekennzeichnet, dass die Öldichtung (34) axial rotorseitig des Olschleuderringes mindestens eine ringförmige Öl-Fangkammer8. Vacuum pump according to one of claims 1-7, characterized in that the oil seal (34) axially rotor side of the oil slinger ring at least one annular oil-trapping chamber
(50,52) mit mindestens einem Ölablaufkanal (54,56) in ein das Lager (20) umgebendes Lagergehäuse (28) aufweist.(50, 52) with at least one oil drain channel (54, 56) in a bearing housing (28) surrounding the bearing (20).
9. Vakuumpumpe nach einem der Ansprüche 6-8, dadurch gekennzeichnet, dass jeder Fang- und Schleuderkammer (48,50,52)9. Vacuum pump according to one of claims 6-8, characterized in that each collecting and centrifugal chamber (48, 50, 52)
• der Öldichtung (34) mindestens ein Lüftungskanal zugeordnet ist .• at least one ventilation duct is assigned to the oil seal (34).
10. Vakuumpumpe nach einem der Ansprüche 1-9, dadurch gekennzeichnet, dass die Rotorwelle (12) fliegend gelagert und an der Saugseite des Rotorabschnittes (14) lagerfrei ausgebildet ist . 10. Vacuum pump according to one of claims 1-9, characterized in that the rotor shaft (12) is overhung and on the suction side of the rotor section (14) is designed to be bearing-free.
11. Vakuumpumpe nach einem der Ansprüche 1-10, dadurch gekennzeichnet, dass der Trennkammer-Lüftungskanal (60,62) im Bereich des tiefsten Punktes der Trennkammer (36) mündet und ein Gefälle aufweist, so dass eine Flüssigkeit aus der Trennkammer (36) ablaufen kann.11. Vacuum pump according to one of claims 1-10, characterized in that the separation chamber ventilation duct (60,62) opens in the region of the lowest point of the separation chamber (36) and has a slope, so that a liquid from the separation chamber (36) can expire.
12. Vakuumpumpe nach einem der Ansprüche 1-11, dadurch gekennzeichnet, dass das Lager axial rotorseitig gedeckelt ausgebildet ist.12. Vacuum pump according to one of claims 1-11, characterized in that the bearing is axially capped on the rotor side.
13. Vakuumpumpe nach einem der Ansprüche 1-12, dadurch gekennzeichnet, dass eine Sperrgasquelle an dem Trennkammer-Lüftungskanal angeschlossen ist, durch die unter Überdruck ein Sperrgas in die Trennkammer (36) eingeleitet wird.13. Vacuum pump according to one of claims 1-12, characterized in that a sealing gas source is connected to the separation chamber ventilation duct, through which a sealing gas is introduced into the separation chamber (36) under excess pressure.
14. Vakuumpumpe nach Anspruch 13, bei der die Sperrgasquelle an das Lagergehäuse (28) angeschlossen wird, so dass in der Trennkammer (36) und im Lagergehäuse (28) näherungsweise der gleiche Druck herrscht .14. Vacuum pump according to claim 13, in which the sealing gas source is connected to the bearing housing (28), so that approximately the same pressure prevails in the separation chamber (36) and in the bearing housing (28).
15. Vakuumpumpe nach einem der Ansprüche 1-13, dadurch gekennzeichnet, dass die Öldichtung (34) mindestens einen Kolbenring (38) aufweist, der über ein Druckgefälle aus der Trennkammer (36) zum Lagergehäuse (28) einen Öl-Durchtritt in die Trennkammer (36) verhindert. 15. Vacuum pump according to one of claims 1-13, characterized in that the oil seal (34) has at least one piston ring (38) which via a pressure drop from the separation chamber (36) to the bearing housing (28) has an oil passage into the separation chamber (36) prevented.
EP03702650A 2002-02-23 2003-02-18 Vacuum pump Expired - Lifetime EP1476661B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10207929A DE10207929A1 (en) 2002-02-23 2002-02-23 vacuum pump
DE10207929 2002-02-23
PCT/EP2003/001598 WO2003071134A1 (en) 2002-02-23 2003-02-18 Vacuum pump

Publications (2)

Publication Number Publication Date
EP1476661A1 true EP1476661A1 (en) 2004-11-17
EP1476661B1 EP1476661B1 (en) 2012-01-11

Family

ID=27674929

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03702650A Expired - Lifetime EP1476661B1 (en) 2002-02-23 2003-02-18 Vacuum pump

Country Status (6)

Country Link
US (1) US7153093B2 (en)
EP (1) EP1476661B1 (en)
JP (2) JP2005517866A (en)
AU (1) AU2003205775A1 (en)
DE (1) DE10207929A1 (en)
WO (1) WO2003071134A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2431613A3 (en) * 2010-09-17 2016-04-06 Pfeiffer Vacuum GmbH Shaft seal for a vacuum pump

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0326613D0 (en) 2003-11-14 2003-12-17 Boc Group Plc Vacuum pump
US7543822B2 (en) * 2004-07-12 2009-06-09 A.W. Chesterton Company Composite rotary seal assembly
DE102005015212A1 (en) * 2005-04-02 2006-10-05 Leybold Vacuum Gmbh Shaft sealing for e.g. rotary screw pump, has seal gap connected with locking gas chamber, and discharge opening connected with gas chamber and suction chamber, where seal gap is arranged between inner and outer sealing rings
DE102005041003A1 (en) * 2005-08-29 2007-03-01 Man Turbo Ag Shaft seal for e.g. single shaft expander, of transmission machine, has ring chamber facing interior of expander and provided with supply of sealing gas, and another chamber turned away to interior and provided with extraction of gas
US20080044279A1 (en) * 2006-08-17 2008-02-21 Orlowski David C Adaptor Frame
JP2008255797A (en) * 2007-03-30 2008-10-23 Anest Iwata Corp Rotor shaft seal device of oil-free rotary compressor
JP2008255796A (en) * 2007-03-30 2008-10-23 Anest Iwata Corp Shaft seal device of oil-free rotary compressor
JP5046379B2 (en) * 2007-03-30 2012-10-10 アネスト岩田株式会社 Rotor shaft seal device for oil-free rotary compressor
DE102007039237A1 (en) 2007-08-20 2009-02-26 Daimler Ag Pump for gas cell system, has shaft, which has rotor section and bearing section, and has sealing device, which has internal gasket and two external gaskets formed in axial direction
DE102008055793B3 (en) * 2008-11-04 2010-09-02 Voith Patent Gmbh Device for sealing a bearing lubricated with a liquid lubricant
DE102010041939A1 (en) * 2010-10-04 2012-04-05 Robert Bosch Gmbh Pump housing and pump
JP5425049B2 (en) * 2010-12-17 2014-02-26 株式会社神戸製鋼所 Water jet screw compressor
CN102654127A (en) * 2011-03-04 2012-09-05 中国科学院沈阳科学仪器研制中心有限公司 Shaft sealing structure for vacuum pump
JP2013002590A (en) * 2011-06-20 2013-01-07 Ulvac Japan Ltd Vacuum device
DE102011108092A1 (en) 2011-07-19 2013-01-24 Multivac Sepp Haggenmüller Gmbh & Co. Kg Cleaning method and system for vacuum pump
EP2570673B1 (en) * 2011-09-13 2014-05-07 Pierburg Pump Technology GmbH Electric vacuum pump for a vehicle
CN102661280A (en) * 2012-04-28 2012-09-12 山东三牛机械有限公司 Shaft end sealing system for driving shaft of Roots blower
WO2014106247A1 (en) * 2012-12-31 2014-07-03 Thermo King Corporation Device and method for extending the lifespan of a shaft seal for an open-drive compressor
CN104047707A (en) * 2013-03-11 2014-09-17 伊顿公司 Supercharger
CN103883357B (en) * 2014-03-20 2016-04-13 泸州市长江液压件装备有限公司 A kind of rotary sealing mechanism of gear shunting motor, gear shunting motor
CN105065276A (en) * 2015-07-22 2015-11-18 宋东方 Combined type sealing device of dry screw vacuum pump
ITUB20152676A1 (en) * 2015-07-30 2017-01-30 Nuovo Pignone Tecnologie Srl ARRANGEMENT OF DRY SEAL GAS COOLING AND METHOD
KR101721933B1 (en) * 2015-11-06 2017-04-03 홍우산업기계(주) Oil seal apparatus and blower comprising the same
DE202016003924U1 (en) 2016-06-24 2017-09-27 Vacuubrand Gmbh + Co Kg Vacuum pump with sealing gas supply
DE102016007672A1 (en) 2016-06-24 2017-12-28 Vacuubrand Gmbh + Co Kg Vacuum pump with sealing gas supply
GB2558954B (en) 2017-01-24 2019-10-30 Edwards Ltd Pump sealing
AU2019377910A1 (en) * 2018-11-08 2021-05-27 Elgi Equipment Ltd Oil-free water-injected screw air compressor
JP7436345B2 (en) 2020-10-30 2024-02-21 株式会社荏原製作所 Shaft sealing device, rotating machine, and assembly method of shaft sealing device

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4196910A (en) * 1977-05-19 1980-04-08 Ishikawajima-Harima Jukogyo Kabushiki Kaisha Shaft sealing device for turbocharger
JPS61104187A (en) 1984-10-29 1986-05-22 Hitachi Ltd Shaft sealing device for vacuum pump
JPS62153597A (en) * 1985-12-27 1987-07-08 Hitachi Ltd Vacuum pump
DE3720250A1 (en) * 1986-06-27 1988-01-14 Battelle Institut E V Pump for transporting gaseous media, in particular for a gas laser
JPS63285279A (en) 1987-05-15 1988-11-22 Hitachi Ltd Shaft seal device for vacuum pump
JP3493850B2 (en) * 1995-11-22 2004-02-03 石川島播磨重工業株式会社 Seal structure of mechanically driven turbocharger
DE29522263U1 (en) 1995-12-02 2001-08-02 Pfeiffer Vacuum GmbH, 35614 Aßlar Multi-shaft vacuum pump
JPH1061671A (en) * 1996-08-22 1998-03-06 Nippon Seiko Kk Closed device
BE1010821A3 (en) 1996-12-23 1999-02-02 Atlas Copco Airpower Nv Dry compressor with spindle seals and a method for fitting a spindle seal to such a compressor
BE1010915A3 (en) * 1997-02-12 1999-03-02 Atlas Copco Airpower Nv DEVICE FOR SEALING A rotor shaft AND SCREW COMPRESSOR PROVIDED WITH SUCH DEVICE.
GB9708397D0 (en) 1997-04-25 1997-06-18 Boc Group Plc Improvements in vacuum pumps
BE1011349A3 (en) 1997-09-04 1999-07-06 Atlas Copco Airpower Nv Compressor unit with at least one non-lubricated compressor element fitted with a spindle seal
DE29807796U1 (en) * 1998-04-30 1999-09-09 GHH-RAND Schraubenkompressoren GmbH & Co. KG, 46145 Oberhausen Sealing arrangement for a shaft journal of a dry-running rotary screw compressor
JP2001207984A (en) * 1999-11-17 2001-08-03 Teijin Seiki Co Ltd Evacuation device
DE19963170A1 (en) * 1999-12-27 2001-06-28 Leybold Vakuum Gmbh Vacuum pump with shaft sealant
ITMI20021222A1 (en) * 2002-06-05 2003-12-05 Nuovo Pignone Spa SEALING SYSTEM FOR CENTRIFUGAL COMPRESSORS THAT ELECT LETHAL GASES

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO03071134A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2431613A3 (en) * 2010-09-17 2016-04-06 Pfeiffer Vacuum GmbH Shaft seal for a vacuum pump

Also Published As

Publication number Publication date
WO2003071134A1 (en) 2003-08-28
AU2003205775A1 (en) 2003-09-09
EP1476661B1 (en) 2012-01-11
JP2005517866A (en) 2005-06-16
US7153093B2 (en) 2006-12-26
DE10207929A1 (en) 2003-09-04
JP5135301B2 (en) 2013-02-06
US20050147517A1 (en) 2005-07-07
JP2009270581A (en) 2009-11-19

Similar Documents

Publication Publication Date Title
EP1476661A1 (en) Vacuum pump
DE2441520C2 (en) Shaft seal for the rotors of a screw compressor using water injection
DE3781482T2 (en) VACUUM GENERATION SYSTEM.
EP1957797B1 (en) Helical screw compressor comprising a cooling jacket
DE68905026T2 (en) MULTI-STAGE ROOTS VACUUM PUMP.
EP0290662B1 (en) Positive-displacement two-shaft vacuum pump
EP2192272A1 (en) Device for sealing a bearing box of a turbocharger
DE3326910A1 (en) OIL-FREE ROTATIONAL COMPRESSOR
EP1394365A1 (en) Turbocharger shaft sealing
DE69614225T2 (en) Sealing an internal combustion engine driven charger
DE60220247T2 (en) HORIZONTAL SPIRAL COMPRESSOR
DE29904409U1 (en) Screw compressor
DE102010055798A1 (en) vacuum pump
DE102010061916B4 (en) Pump for pumping a medium and lubricant system
CH628709A5 (en) Roots pump
EP3371458B1 (en) Dry vacuum pump
EP0569424B1 (en) Dry-running vacuum pump
EP2431613A2 (en) Shaft seal for a vacuum pump
DE4327506A1 (en) Turbo vacuum pump assembly - has housing with suction and delivery apertures and contg. evacuating pump which compresses gas sucked in through suction aperture
DE4201486A1 (en) Oil-free screw compressor installation - has turbo supercharger which raises atmospheric air pressure prior to compressor entry
DE20302989U1 (en) Rotary pump
EP0942172B1 (en) Vacuum pump with multiple driven shafts
DE29904411U1 (en) Screw compressor
DE102004050415A1 (en) Gas compression device that can prevent lubricant leakage
DE19849237C2 (en) Sealing system for a drive unit consisting of motor and gear

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20040807

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO

17Q First examination report despatched

Effective date: 20061012

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE FR GB IT LI

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: DE

Ref legal event code: R081

Ref document number: 50314167

Country of ref document: DE

Owner name: LEYBOLD GMBH, DE

Free format text: FORMER OWNER: LEYBOLD VAKUUM GMBH, 50968 KOELN, DE

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: OERLIKON LEYBOLD VACUUM GMBH

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 50314167

Country of ref document: DE

Effective date: 20120308

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 50314167

Country of ref document: DE

Owner name: LEYBOLD GMBH, DE

Free format text: FORMER OWNER: LEYBOLD VACUUM GMBH, 50968 KOELN, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 50314167

Country of ref document: DE

Representative=s name: VON KREISLER SELTING WERNER, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 50314167

Country of ref document: DE

Representative=s name: VON KREISLER SELTING WERNER - PARTNERSCHAFT VO, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 50314167

Country of ref document: DE

Representative=s name: DOMPATENT VON KREISLER SELTING WERNER - PARTNE, DE

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120229

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120229

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20120111

26N No opposition filed

Effective date: 20121012

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 50314167

Country of ref document: DE

Effective date: 20121012

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20140218

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20140220

Year of fee payment: 12

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20150218

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20151030

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150218

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150302

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 50314167

Country of ref document: DE

Owner name: LEYBOLD GMBH, DE

Free format text: FORMER OWNER: OERLIKON LEYBOLD VACUUM GMBH, 50968 KOELN, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 50314167

Country of ref document: DE

Representative=s name: DOMPATENT VON KREISLER SELTING WERNER - PARTNE, DE

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20220225

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 50314167

Country of ref document: DE