EP3629366B1 - Vacuum system and vacuum pump - Google Patents

Description

The present invention relates to a vacuum system, in particular a gas analysis system and/or mass spectrometry system, comprising a vacuum pump with a pump-active area in which a gas can be pumped by means of an active pump element, and a device for generating a beam of particles. Such vacuum systems are in EP 1 193 497 A2 and U.S. 2007/0148020 A1 disclosed. Further prior art forms the WO 2016/142683 A1 .

Particle beams are often generated and used in vacuum systems, for example in mass spectrometry systems. In known mass spectrometry systems, deflection devices are often used, for example, by means of which the beam can be deflected in such a way that different components of the beam are deflected differently, so that at least a first and a second partial beam can be formed. On the one hand, these have the purpose that the particle beam is divided so that only certain components to be analyzed, which in particular form the first partial beam, are guided in a desired direction, in particular to an analyzer unit. After passing through the deflection device, other components, which in particular form the second partial beam, have a different direction than the components to be analyzed. The deflection device thus acts as a filter. On the other hand, such a deflection, often by about 90°, enables a compact design of the mass spectrometry system.

It is an object of the invention to improve the evacuation in the area of the jet in a vacuum system of the type mentioned at the outset.

This object is achieved by a vacuum system according to claim 1, and in particular in that the jet is guided into the active pumping area of the vacuum pump.

As a result, the beam or its molecules are pumped out directly and the evacuation is improved. The beam guided into the active pump area can be, for example, a partial beam after passing through a filter and/or separation device. In general, however, use is made here of the fact that the beam has a particle stream with a specific direction and that this direction is advantageously used to capture the particles directly. In this respect, it can also be a type of main jet and/or an overall jet, for example. In general, the invention is aimed at increasing the probability of capture of a respective particle of the beam. This is achieved by the invention in a structurally particularly simple manner.

The vacuum system can preferably include a deflection device, by means of which the jet can be deflected in such a way that different components of the jet are deflected differently, so that at least a first and a second partial jet can be formed, with the second partial jet being guided into the pump-active region. In general, the jet is therefore in particular at least partially guided into the active pumping area. Insofar as the beam is mentioned below, it goes without saying that a partial beam, in particular a second partial beam, can also be meant.

The possibility of the first partial beam being contaminated by molecules from the second partial beam is particularly low. In this context, the invention thus enables in particular a good separation of the partial beams and a high quality of the first partial beam, which can have a positive effect on an analysis of the first partial beam, for example.

The gas components of the second partial beam are often those components that are undesirable with regard to an analysis task, that is to say they represent undesirable molecules. These can be referred to as dirt particles. In the case of deflection devices of the prior art, second partial jets or dirt particles typically land on static components in the area of or adjacent to the deflection device. A diaphragm is also often arranged downstream of the deflection device, through which the first partial beam can pass, but on the surface of which the dirt particles impinge away from the first partial beam or a passage for this. All dirt particles that land on static surfaces desorb after a certain time from the surface in question with a statistical distribution of direction. On the one hand, this means an increased probability that dirt particles will reach the analyzer unit despite all the filter devices. On the other hand, the dirt particles can collide with the gas molecules to be analyzed in the first partial beam and thus reduce its quality. This is because the molecules of the first partial beam are thereby deflected and the number of molecules to be analyzed that reach the analyzer unit is reduced.

The invention now makes it possible for dirt particles to be removed directly by the pumping action of the vacuum pump. In this case, the direction or kinetic energy of the dirt particles in the particle beam is advantageously used in order to actively feed them to the active pumping area of the vacuum pump. The active pumping area then actively gives the dirt particles or the second partial jet a preferred direction in the pumping direction, so that the dirt particles are actively guided away from the first partial jet and in particular from an analyzer unit. In the prior art, effective evacuation of vacuum chambers of a gas analysis system is often difficult, namely due to disadvantageous geometries and conductivity values. However, better evacuation allows for better analysis accuracy. The invention makes it possible by utilizing the direction of the beam or the kinetic energy of the particles and due to the active discharge, better evacuation and thus, in particular, improved analysis accuracy.

The active pumping area is generally understood to be an effective area of an active pumping element of the vacuum pump, for example a rotor or rotor element, in particular a turbo rotor disk. In the case of a rotor, the beam, in particular the second partial beam, is guided in particular into an active rotor area. In the case of a turbomolecular vacuum pump or turbo rotor disk, this is in particular an area swept over by the rotor blades during operation. In particular, a rotor core that does not itself have an active pumping effect, but only has a structural function, does not belong to the active pumping area. It is generally advantageous if the beam is not guided onto a rotor core or the beam is guided past a rotor core.

The deflection device deflects different components of the particle beam differently. Typically, certain components are not deflected at all, namely uncharged components in particular. It is therefore generally the case that at least one of the first and second partial beams must be deflected by the deflection device in order to split the partial beams into such. For example, the second partial beam cannot be deflected by the deflection device or can be aligned in continuation of the particle beam in front of the deflection device. Uncharged particles often form undesirable molecules or dirt particles with regard to the analysis task. If the partial jet of uncharged components is guided into the active pumping area, a particularly large proportion of dirt particles in particular will be discharged directly.

The molecules of the jet, which is guided into the pump-active area, are in particular captured directly by at least one pump-active element of the vacuum pump in the pump-active area. Associated with an as With the pumping element designed as a turbo rotor, this means in particular that the molecules of the jet pass through the area swept by the rotor blades and are then "held" downstream by the well-known principle of operation of the turbo rotor, meaning that - from a physical point of view - the probability is reduced that a respective Molecule back into the area upstream of the rotor blades.

After passing through a deflection device, different partial beams generally comprise different components and have different directions. In this case, a partial beam does not necessarily have only one component or one type of particle. In particular, the second partial jet can, for example, have a large number of components, all of which can form dirt particles. This applies in particular to a second partial beam, which is directed straight ahead in relation to the common beam before passing through the deflection device and/or has uncharged molecules. However, the first partial beam can also have fundamentally different components, with the differences typically being small.

In addition, it goes without saying that the deflection device typically does not split the common particle beam into just two absolutely discrete partial beams. Rather, particle beams in such systems typically have a large number of components, with mostly only a small part of the components to be analyzed, often a specific type of ion and/or molecule. Consequently, after passing through the deflection device, a large number of, in particular second, partial beams typically form in a fan-like manner. In principle, at least one second partial jet can be guided into the active pumping area, but several second partial jets or partial jets with dirt particles are advantageously guided into the active pumping area in order to remove as many dirt particles as possible directly. How many second partial beams can be guided into the active pumping area and what angular range of the fan from Partial beams can be guided into the active pump area is particularly dependent on the geometric conditions in the vacuum pump. In principle, therefore, more than two partial beams can also be formed, for example a plurality of first partial beams which are not guided into the pump-active region and/or a plurality of second partial beams which are guided into the pump-active region.

The second partial beam can in particular have uncharged particles and/or particles of a carrier gas or consist essentially of such. A carrier gas often makes up a large part of the pressure in a vacuum system, particularly a mass spectrometry system. Accordingly, the invention advantageously allows a large proportion of particles that are not intended to be part of the first partial beam to be pumped off directly. A carrier gas is, for example, an inert gas and/or air. For example, helium can be used as the carrier gas. If air forms the carrier gas, the second partial jet comprises, for example, oxygen and/or nitrogen, in particular uncharged particles thereof. In general, the second partial beam comprises in particular mainly one type of molecule and/or has a particle flow that is many times higher than that of the first particle beam. Typically, in a gas analysis system, particularly a mass spectrometer, a molecular species to be analyzed makes up only a small portion of the gas flow and/or a carrier gas makes up a vast majority.

An important idea of the invention in connection with the deflection device is that gas components are deflected differently and as large a part as possible of gas components that are undesirable, especially with regard to an analysis task, is guided directly into the active pumping area using their direction. In this way, these, in particular undesired, components can be actively removed, namely in particular out of the area of the first partial beam and, for example, away from an analysis area or an area of an analyzer unit.

The deflection device divides the particle beam into partial beams. The beam before passing through the deflection device is also referred to here as a common (particle) beam, in contrast to the partial beams that form during and/or after passing through the deflection device.

In principle, the vacuum system can, for example, also have a plurality of deflection devices, for example each with advantageous guidance of a partial beam into a pump-active region of a vacuum pump. In general, in addition to a deflection device, for example, a wide variety of other filter elements can also be used, such as an aperture and/or a quadrupole.

According to one embodiment, it is provided that the jet is guided into the active pumping region with at least one directional component in the pumping direction. This supports the pumping action of the pump-active area and the molecules of the jet are removed particularly effectively.

In particular, it can be provided that the first partial beam is not guided into the pump-active area. Alternatively or additionally, the first partial beam can be guided to an area outside the vacuum pump. In particular, the first partial beam can be guided to an analyzer unit, for example directly or through at least one further filter element, in particular a diaphragm. In principle, the first partial beam can be routed past or through a housing of the vacuum pump.

In general, the vacuum pump can include a rotor which can be driven to rotate about a rotor axis. An active pumping element of the vacuum pump or of the active pumping area can be coupled to the rotor, so that the rotor drives the pump element. In particular, the jet can be guided into an active rotor area of the rotor or of the active pump element.

According to a further embodiment, it is provided that a pumping direction and/or a rotor axis of an active pumping element and/or the vacuum pump is aligned obliquely with respect to a direction of the jet, in particular before passing through one or the deflection device. As a result, the beam and in particular a second partial beam directed straight ahead in relation to a common beam can be guided particularly advantageously with regard to the pumping effect into the active pumping region. In addition, such an arrangement is particularly advantageous in terms of installation space. In particular, an angle between a pumping direction and/or a rotor axis of the active pump element and/or the vacuum pump and a direction of the jet, in particular before passing through a deflection device, can be in the range of 40° to 60°, preferably in the range of 50° up to 55°. These values are influenced by the particle speed, the rotor blade rotation speed in the "target area" of the jet and the rotor blade angle or angle of attack there. The angle can be optimized three-dimensionally depending on the case.

Preferably, a pumping direction and/or a rotor axis of the active pumping element and/or the vacuum pump can be aligned obliquely in relation to a direction of the first and/or the second partial jet after passage through the deflection device. This is also conducive to a compact design.

In general, the vacuum pump can be designed in one or more stages, for example. Multi-stage means that the vacuum pump has at least two pump stages. At least two pump stages can preferably be connected in series. The pump stages can be driven by a common rotor, for example.

In one embodiment, it is provided that the vacuum pump has at least two pump stages, preferably connected in series, with an intermediate stage region being arranged between the pump stages, in particular in the pumping direction. In particular, the pumping stages can be spaced apart over this interstage region. The beam is preferably passed through the interstage region. In principle, the beam, in particular a second partial beam, can be guided into a pump stage which is arranged downstream of the intermediate stage region, in particular in the pumping direction. Thus, on the one hand, a particularly compact design and, on the other hand, particularly good removal of the particles, in particular dirt particles, are made possible.

A pumping stage is defined in particular by an active pumping element, in particular in cooperation with a static and/or passive element. In the case of a turbomolecular pump, a peripheral row of rotor blades, in particular a turbo rotor disk, in particular in cooperation with a stator disk, thus forms a pump stage. In this context it should be mentioned that a turbo rotor can in principle, for example, be designed with several rows of blades connected in one piece and/or can have one or more turbo rotor disks.

The jet can generally preferably be directed into the effective range of the active pumping element and/or onto a rotating element, for example a turbo rotor disk.

The first partial beam can preferably be led out of the vacuum pump after passing through the intermediate stage area and/or a deflection device, for example to an analyzer unit. In general, an analyzer unit can be designed as a detector, for example.

According to a development, it is provided that the vacuum pump has a first intermediate connection on the intermediate stage area for the entry of the jet into the intermediate stage area and/or a second intermediate connection for the exit of the first partial jet from the intermediate stage area. The first and/or the second intermediate connection can, for example, have a flange, in particular its own flange.

The intermediate connections can preferably be arranged at least essentially opposite one another, in particular in relation to a rotor axis and/or pumping direction. The, in particular common, beam and/or the first partial beam can thus advantageously enter or exit the intermediate stage region. However, the intermediate connections are not necessarily exactly radially opposite, e.g. H. offset by 180° around the rotor axis. On the other hand, an off-centre connection axis of the intermediate connections, which in particular leads past a rotor core, is preferred. This enables a particularly advantageous gas flow. Nevertheless, radially opposite intermediate connections are fundamentally possible, in particular in connection with a deflection device which at least partially deflects the gas jet around a rotor core.

The intermediate connections can preferably be formed separately from one another and/or arranged at a distance from one another in the circumferential direction. A housing wall preferably extends in the circumferential direction between the intermediate connections, in particular over at least 20°, preferably at least 35°. The quality of the first partial beam is further improved by separating the intermediate connections.

A deflection device can have a magnetic and/or electric field, for example. A magnetic field can be provided, for example, by a permanent magnet or, for example, by an electromagnet will. A magnetic and/or electric field causes charged particles to be deflected differently, in particular depending on their mass. Correspondingly, the deflection device can have a field generating device, such as a magnet or an electrode.

The deflection device can preferably be effective and/or arranged in or on the intermediate stage area. The term "effective" relates in particular to the electric and/or magnetic field of the deflection device, ie in general to its effective range. The deflection device can, for example, also have components, such as a field generation device, outside of its effective range. Consequently, the term "arranged" also refers at least to the effective range of the deflection device. In particular, an electric and/or magnetic field of the deflection device can be arranged in and/or on the intermediate stage area. Alternatively or additionally, a deflection device or an electric and/or magnetic field can also be arranged radially outside the intermediate stage area, for example at or in the area of an intermediate connection, in particular that intermediate connection for the entry of the common beam.

The arrangement of a, in particular (electro)magnetic, deflection device in the area of at least one of the intermediate connections is also advantageously possible. An arrangement of passive and/or permanent-magnetic as well as active deflection elements is possible on the one hand in the vacuum area or on the other hand also outside of the vacuum area or in the atmosphere. A deflection device or a deflection element can be arranged, for example, in the area of the pump housing and/or on the outside of the pump housing. In principle, the deflection device itself can also be arranged outside the vacuum area in such a way that it is effective in the vacuum area, that is to say that in particular an electric and/or magnetic field extends into the vacuum area, in particular into the intermediate stage area.

For example, several deflection devices can also be provided, also in or on the intermediate stage area. For example, two deflection devices can be provided at, in or on the respective intermediate connections. The use of several deflection devices is particularly advantageous with regard to the installation space. Thus, one large deflection device does not have to be provided, which completely fulfills the desired deflection, but rather the desired deflection can be divided among a number of deflection devices, which can subsequently be made smaller. In this way, they can be arranged more favorably with regard to the overall installation space required.

It is generally advantageous if a magnetic and/or electric field of a deflection device penetrates the rotating parts of a rotor as little as possible. In this context, several and/or small deflection devices, which can preferably also be arranged outside of the intermediate stage area, have proven to be advantageous. In this way, eddy current losses in the rotor and associated, undesirable heating in the rotor can be reduced.

The jet can preferably be aligned eccentrically in relation to a rotor axis of the vacuum pump and/or be guided past a rotor core, in particular one that is not pump-active. This applies in particular to the common beam, ie before passing through the deflection device, and/or to the first and/or second partial beam.

Advantageously, it can be provided that the beam, in particular the second partial beam, is guided into the active pumping area in a direction that supports the pumping action. Thus, utilizing the underlying pumping principle, the beam can be guided into the active pumping area in such a way that the particles of the beam are captured particularly reliably. in the In the case of a turbomolecular vacuum pump or turbopump stage, the jet can preferably have a direction which runs at least with a component counter to the direction of rotation of the turborotor when it enters the pumping-active region. The jet thus runs counter to the rotor blades. In this case, the jet preferably also has a directional component in the pumping direction or parallel to the rotor axis in the direction of the outlet. Even if introducing the jet in the opposite direction is advantageous, it goes without saying that it is also possible, and in a certain respect also advantageous, for the jet to be guided co-rotating with the rotor blades into the active pumping area, i.e. with a directional component in the direction of rotation of the rotor blades. In principle, it is also possible to introduce the jet parallel to the rotor axis, i.e. neither in the opposite direction nor in the same direction.

In the case of a turbomolecular pump, it is particularly advantageous for the jet to enter in the opposite direction to the local direction of rotation of the rotor, so that the particles can at best pass through the first rotor disk without blade contact and only make initial contact with the stator disk below, with subsequent deflection in the usual cosine distribution in the molecular pressure range . In general, the jet can preferably be guided in such a way that its particles are captured by pump elements designed as rotor elements, such as turbo rotor blades, as far as possible without colliding with them. Preferably, as many particles of the jet as possible should be able to pass through the plane of the turbo rotor blades without colliding. For this purpose, the jet is aligned in particular taking into account its particle speed, the angle of attack of the rotor blades and/or the rotational speed of the rotor or rotor blades.

The selection of the point of entry of the jet into the active pumping area in relation to the active rotor disk diameter or the effective outer and inner diameters of the rotor blades is also subject to optimization, since the first deflection point on a stator disk behind it has a decisive influence will. This deflection point should advantageously lie within an imaginary ring cylinder in the axial continuation of the area swept by the rotor blades, so that optimal further pumping can take place. For example, it can be provided that the active pump element is formed by a turbo rotor disk with a plurality of rotor blades distributed over the circumference of the turbo rotor disk, the rotor blades having a radial extent from a radially inner end to a radially outer end of the rotor blades. In this case, the jet can preferably be guided onto a radial region of the rotor blades which is spaced from the radially inner end and/or from the radially outer end of the rotor blades by at least a quarter of the radial extension. In particular, the jet can be guided onto the rotor blades approximately radially in the middle or approximately at a third of the radial extent measured from the radially outer end of the rotor blades. These features serve to be able to capture as many particles as possible of the beam, in particular of the second partial beam, or as many dirt particles as possible.

Also advantageous in this respect, but independently of this, it can be provided that the pump-active element is a rotor element, the jet being guided into the pump-active area of the rotor element in such a way that at an entry point of the jet into the pump-active area, the jet has a direction, in particular with respect to a cross-section perpendicular to the rotor axis, directed outwards, tangentially or inwards.

In further embodiments, it is provided that the active pump element is formed by a turbo rotor disk with a plurality of rotor blades distributed over the circumference of the turbo rotor disk, the rotor blades having an angle of attack in relation to the rotor axis and the jet being flatter when it enters the active pumping area than the rotor blades, corresponding to the rotor blades being slanted or slanted steeper is than the rotor blades. An advantageous angle is subject to optimization and depends on many boundary conditions.

According to a further embodiment, it is provided that the vacuum pump has a multi-stage design, the second partial jet is guided into a pump stage and the first partial jet is guided into a chamber which is connected to a further pump stage of the vacuum pump, in particular upstream in the pumping direction, in particular the first in the pumping direction connected. This embodiment permits a particularly compact construction with simultaneously high quality of the first partial beam, in that the same vacuum pump captures the second partial beam on the one hand and evacuates the chamber on the other. The pump stage, into which the second partial beam is guided, is arranged downstream of the, in particular first, pump stage connected to the chamber, in particular in the pumping direction, and in particular adjoins an intermediate stage region in the pumping direction, in particular through which the beam is passed.

The vacuum pump can, for example, generally be designed as a molecular pump, for example as a turbomolecular pump and/or Holweck pump. In principle, the vacuum pump can also be designed as a cryopump. Finally, combinations of different pump types, for example in the form of different pump stages, are advantageous.

The object of the invention is also achieved by a vacuum pump according to the independent claim directed thereto. The vacuum pump comprises at least two pump stages, in particular those connected in series, with an intermediate stage region being arranged between the pump stages, in particular in the pumping direction. At the interstage area, the vacuum pump has a first intermediate connection for entering a particle beam into the interstage area and a second intermediate connection for exiting a particle beam from the interstage area. The intermediate terminals are circumferential separated and spaced apart. The separation and spaced arrangement of the intermediate connections improves the quality of the exiting, first partial beam and thus the analysis result.

In particular, exactly two intermediate connections can be provided on the intermediate stage area. In principle, however, more than two intermediate connections on the intermediate stage area are also possible. At least one of the intermediate connections, preferably both intermediate connections, can have its own flange, for example.

In addition, in principle, a plurality of intermediate stage regions with passage of the particle beam can also be provided.

The intermediate terminals are circumferentially separated and spaced apart, specifically with a housing wall extending circumferentially between the intermediate terminals. The housing wall preferably extends in the circumferential direction over an angular range of at least 20°, in particular at least 40°, in relation to a central and/or rotor axis.

According to one embodiment, it is provided that the intermediate connections are arranged in such a way that no straight line can be laid through the intermediate connections. The intermediate connections are thus not "optically transparent" and one cannot "see straight through" the intermediate connections.

In general, the intermediate connections can preferably be arranged or aligned in the shape of an arrow, with the direction of the arrow preferably pointing essentially in the pumping direction of the vacuum pump.

For example, at least one of the intermediate connections can have a flange plane that is arranged obliquely with respect to a rotor axis. an angle between the flange plane and the rotor axis can preferably be in the range of 40° to 60°. In particular, both intermediate connections can be arranged at an angle and, in particular, with the angle range specified relative to the rotor axis.

A particle beam can be guided through the intermediate stage area in such a way that part of the beam, namely a first partial beam, exits the intermediate stage area again and that another part of the beam, namely a second partial beam, is guided into an active pumping area of the vacuum pump.

According to one embodiment, the vacuum pump comprises a deflection device for a particle beam in the intermediate stage region, by means of which the beam can be divided into at least two partial beams and which is set up so that a first partial beam is guided to the second intermediate connection, and in particular through this to an analyzer unit, and a second partial beam is guided into a pump stage downstream of the intermediate stage region.

The intermediate connections can advantageously be arranged at least essentially opposite one another, in this case preferably not radially opposite one another, but with a connecting line running eccentrically with respect to a pump cross section.

The object is also achieved by a gas analysis method, in particular a mass spectrometry method, according to the claim directed thereto. In particular, this method is performed with a vacuum system as disclosed herein and/or with a vacuum pump as disclosed herein. In this case, a or the vacuum pump is provided with an active pumping area in which a gas can be pumped by means of an active pump element, a beam of particles to be analyzed is generated and the beam is deflected by means of a deflection device in such a way that different components of the beam are deflected differently, so that at least a first and a second partial beam are formed, the second partial beam being guided into the active pumping area of the vacuum pump, and the first partial beam not being guided into the active pumping area of the vacuum pump, but being analyzed.

It goes without saying that the vacuum system according to the invention and its embodiments can be advantageously further developed individually and in combination at least analogously by the features of the vacuum pump according to the invention and the gas analysis method and their embodiments, and vice versa.

Fig. 1

eine perspektivische Ansicht einer Turbomolekularpumpe,

Fig. 2

eine Ansicht der Unterseite der Turbomolekularpumpe von Fig. 1,

Fig. 3

einen Querschnitt der Turbomolekularpumpe längs der in Fig. 2 gezeigten Schnittlinie A-A,

Fig. 4

eine Querschnittsansicht der Turbomolekularpumpe längs der in Fig. 2 gezeigten Schnittlinie B-B,

Fig. 5

eine Querschnittsansicht der Turbomolekularpumpe längs der in Fig. 2 gezeigten Schnittlinie C-C,

Fig. 6 bis 9

schematisch verschiedene Ausführungsformen eines erfindungsgemäßen Vakuumsystems,

Fig. 10

eine Vakuumpumpe im Querschnitt mit einer Umlenkeinrichtung,

Fig. 11

eine mehrstufige Vakuumpumpe mit Zwischenanschlüssen,

Fig. 12 bis 14

verschiedene Ausrichtungsmöglichkeiten für den Strahl in Bezug auf einen Rotor einer Turbomolekularpumpe.

The invention is described below by way of example using advantageous embodiments with reference to the attached figures. They show, each schematically:

1

a perspective view of a turbomolecular pump,

2

a view of the bottom of the turbo molecular pump from 1 ,

3

a cross-section of the turbomolecular pump along the in 2 shown cutting line AA,

4

a cross-sectional view of the turbomolecular pump along the in 2 shown cutting line BB,

figure 5

a cross-sectional view of the turbomolecular pump along the in 2 shown cutting line CC,

Figures 6 to 9

schematically different embodiments of a vacuum system according to the invention,

10

a vacuum pump in cross section with a deflection device,

11

a multi-stage vacuum pump with intermediate connections,

Figures 12 to 14

Different jet orientation options in relation to a turbomolecular pump rotor.

In the 1 The turbomolecular pump 111 shown comprises a pump inlet 115 surrounded by an inlet flange 113, to which a recipient, not shown, can be connected in a manner known per se. The gas from the recipient can be sucked out of the recipient via the pump inlet 115 and conveyed through the pump to a pump outlet 117 to which a backing pump, such as a rotary vane pump, can be connected.

The inlet flange 113 forms when the vacuum pump is aligned according to FIG 1 the upper end of the housing 119 of the vacuum pump 111. The housing 119 comprises a lower part 121 on which an electronics housing 123 is arranged laterally. Electrical and/or electronic components of the vacuum pump 111 are accommodated in the electronics housing 123, for example for operating an electric motor 125 arranged in the vacuum pump. A plurality of connections 127 for accessories are provided on the electronics housing 123. In addition, a data interface 129, for example according to the RS485 standard, and a power supply connection 131 are arranged on the electronics housing 123.

A flood inlet 133, in particular in the form of a flood valve, is provided on the housing 119 of the turbomolecular pump 111, via which the vacuum pump 111 can be flooded. In the area of the lower part 121 there is also a sealing gas connection 135, which is also referred to as a flushing gas connection, through which flushing gas to protect the electric motor 125 (see e.g 3 ) before the The gas delivered by the pump can be brought into the engine compartment 137 in which the electric motor 125 in the vacuum pump 111 is housed. Two coolant connections 139 are also arranged in the lower part 121, one of the coolant connections being provided as an inlet and the other coolant connection being provided as an outlet for coolant, which can be conducted into the vacuum pump for cooling purposes.

The lower side 141 of the vacuum pump can serve as a standing surface, so that the vacuum pump 111 can be operated standing on the underside 141 . However, the vacuum pump 111 can also be fastened to a recipient via the inlet flange 113 and can thus be operated in a suspended manner, as it were. In addition, the vacuum pump 111 can be designed in such a way that it can also be operated when it is oriented in a different way than in FIG 1 is shown. It is also possible to realize embodiments of the vacuum pump in which the underside 141 cannot be arranged facing downwards but to the side or directed upwards.

At the bottom 141, the in 2 shown, various screws 143 are also arranged, by means of which components of the vacuum pump that are not further specified here are fastened to one another. For example, a bearing cap 145 is attached to the underside 141 .

In addition, fastening bores 147 are arranged on the underside 141, via which the pump 111 can be fastened, for example, to a support surface.

In the Figures 2 to 5 a coolant line 148 is shown, in which the coolant fed in and out via the coolant connections 139 can circulate.

Like the sectional views of the Figures 3 to 5 show, the vacuum pump comprises several process gas pump stages for conveying the process gas present at the pump inlet 115 to the pump outlet 117.

A rotor 149 is arranged in the housing 119 and has a rotor shaft 153 which can be rotated about an axis of rotation 151 .

The turbomolecular pump 111 comprises a plurality of turbomolecular pumping stages connected in series with one another in a pumping manner, with a plurality of radial rotor disks 155 fastened to the rotor shaft 153 and stator disks 157 arranged between the rotor disks 155 and fixed in the housing 119. A rotor disk 155 and an adjacent stator disk 157 each form a turbomolecular pump stage. The stator discs 157 are held at a desired axial distance from one another by spacer rings 159 .

The vacuum pump also comprises Holweck pump stages which are arranged one inside the other in the radial direction and are connected in series with one another for pumping purposes. The rotor of the Holweck pump stages comprises a rotor hub 161 arranged on the rotor shaft 153 and two Holweck rotor sleeves 163, 165 in the shape of a cylinder jacket, fastened to the rotor hub 161 and carried by it, which are oriented coaxially to the axis of rotation 151 and are nested in one another in the radial direction. Also provided are two cylinder jacket-shaped Holweck stator sleeves 167, 169, which are also oriented coaxially with respect to the axis of rotation 151 and are nested in one another when viewed in the radial direction.

The pumping-active surfaces of the Holweck pump stages are formed by the lateral surfaces, ie by the radial inner and/or outer surfaces, of the Holweck rotor sleeves 163, 165 and the Holweck stator sleeves 167, 169. The radially inner surface of the outer Holweck stator sleeve 167 abuts the radially outer surface of the outer Holweck rotor sleeve 163 forming a radial Holweck gap 171 and forms the first Holweck pump stage following the turbomolecular pumps. The radially inner surface of the outer Holweck rotor sleeve 163 faces the radially outer surface of the inner Holweck stator sleeve 169 to form a radial Holweck gap 173 and therewith forms a second Holweck pumping stage. The radially inner surface of the inner Holweck stator sleeve 169 faces the radially outer surface of the inner Holweck rotor sleeve 165 to form a radial Holweck gap 175 and therewith forms the third Holweck pumping stage.

At the lower end of the Holweck rotor sleeve 163, a radially running channel can be provided, via which the radially outer Holweck gap 171 is connected to the middle Holweck gap 173. In addition, a radially extending channel can be provided at the upper end of the inner Holweck stator sleeve 169, via which the middle Holweck gap 173 is connected to the radially inner Holweck gap 175. As a result, the nested Holweck pump stages are connected in series with one another. Furthermore, a connecting channel 179 to the outlet 117 can be provided at the lower end of the radially inner Holweck rotor sleeve 165 .

The above-mentioned pumping-active surfaces of the Holweck stator sleeves 163, 165 each have a plurality of Holweck grooves running in a spiral shape around the axis of rotation 151 in the axial direction, while the opposite lateral surfaces of the Holweck rotor sleeves 163, 165 are smooth and the gas for operating the Advance vacuum pump 111 in the Holweck grooves.

A roller bearing 181 in the region of the pump outlet 117 and a permanent magnet bearing 183 in the region of the pump inlet 115 are provided for the rotatable mounting of the rotor shaft 153 .

In the area of the roller bearing 181 , a conical spray nut 185 is provided on the rotor shaft 153 with an outer diameter that increases toward the roller bearing 181 . The injection nut 185 is in sliding contact with at least one stripper of an operating fluid store. The resource reservoir comprises a plurality of absorbent discs 187 stacked on top of one another, which are impregnated with a resource for the roller bearing 181, e.g. with a lubricant.

During operation of vacuum pump 111, the operating fluid is transferred by capillary action from the operating fluid reservoir to the rotating spray nut 185 via the scraper and, as a result of the centrifugal force, is conveyed along the spray nut 185 in the direction of the increasing outer diameter of the spray nut 185 to the roller bearing 181, where it e.g. fulfills a lubricating function. The roller bearing 181 and the operating fluid reservoir are surrounded by a trough-shaped insert 189 and the bearing cover 145 in the vacuum pump.

The permanent magnet bearing 183 comprises a bearing half 191 on the rotor side and a bearing half 193 on the stator side, which each comprise a ring stack of a plurality of permanent magnetic rings 195, 197 stacked on top of one another in the axial direction. The ring magnets 195, 197 lie opposite one another, forming a radial bearing gap 199, the ring magnets 195 on the rotor side being arranged radially on the outside and the ring magnets 197 on the stator side being arranged radially on the inside. The magnetic field present in the bearing gap 199 produces magnetic repulsive forces between the ring magnets 195, 197, which cause the rotor shaft 153 to be supported radially. The ring magnets 195 on the rotor side are carried by a support section 201 of the rotor shaft 153, which radially surrounds the ring magnets 195 on the outside. The ring magnets 197 on the stator side are carried by a support section 203 on the stator side, which extends through the ring magnets 197 and is suspended on radial struts 205 of the housing 119 . The ring magnets 195 on the rotor side are parallel to the axis of rotation 151 by a cover element coupled to the carrier section 203 207 fixed. The stator-side ring magnets 197 are fixed parallel to the axis of rotation 151 in one direction by a fastening ring 209 connected to the support section 203 and a fastening ring 211 connected to the support section 203 . A disc spring 213 can also be provided between the fastening ring 211 and the ring magnet 197 .

An emergency or safety bearing 215 is provided within the magnetic bearing, which runs idle without contact during normal operation of the vacuum pump 111 and only engages in the event of an excessive radial deflection of the rotor 149 relative to the stator, in order to create a radial stop for the rotor 149 to form since collision of the rotor-side structures with the stator-side structures is prevented. The backup bearing 215 is designed as an unlubricated roller bearing and forms a radial gap with the rotor 149 and/or the stator, which causes the backup bearing 215 to be disengaged during normal pumping operation. The radial deflection at which the backup bearing 215 engages is dimensioned large enough so that the backup bearing 215 does not engage during normal operation of the vacuum pump, and at the same time small enough so that the rotor-side structures collide with the stator-side structures under all circumstances is prevented.

The vacuum pump 111 includes the electric motor 125 for rotating the rotor 149. The armature of the electric motor 125 is formed by the rotor 149, the rotor shaft 153 of which extends through the motor stator 217. A permanent magnet arrangement can be arranged radially on the outside or embedded on the section of the rotor shaft 153 that extends through the motor stator 217 . Between the motor stator 217 and the section of the rotor 149 extending through the motor stator 217 there is a space 219 which comprises a radial motor gap over which the motor stator 217 and the permanent magnet arrangement for the transmission of the drive torque can affect each other magnetically.

The motor stator 217 is fixed in the housing inside the motor room 137 provided for the electric motor 125 . A sealing gas, which is also referred to as flushing gas and which can be air or nitrogen, for example, can get into the engine compartment 137 via the sealing gas connection 135 . The sealing gas can protect the electric motor 125 from process gas, e.g. from corrosive components of the process gas. The engine compartment 137 can also be evacuated via the pump outlet 117, i.e. the vacuum pressure produced by the backing pump connected to the pump outlet 117 prevails in the engine compartment 137 at least approximately.

What is known as a labyrinth seal 223 can also be provided between the rotor hub 161 and a wall 221 delimiting the motor compartment 137, in particular in order to achieve better sealing of the motor compartment 217 in relation to the Holweck pump stages located radially outside.

The pumps and systems described below are highly schematic and simplified. For the purpose of practical implementation, they are advantageous with one or more features of the above, in particular with reference to the Figures 1 to 5 described pump executable.

In 6 a gas analysis system 20 is shown, which includes a vacuum pump 22, a deflection device 24 for a particle beam 26 and an analyzer unit 28. The deflection device 24 is set up to split the beam 26 into at least a first partial beam 30 and a second partial beam 32 in that the components of the relevant partial beams are deflected by the deflection device 24 to different extents.

The deflection device 24 is only indicated here by a circle, which symbolizes a magnetic field or electric field generated by the deflection device 24 .

The molecules of the beam 26 before the passage of the deflection device 24, ie the common beam, have a specific speed and are partially charged. In the field of the deflection device 24, the molecules are deflected to different extents, in particular as a function of their mass and their charge (at different speeds also as a function of this). Uncharged molecules are not deflected and fly straight ahead. Here, these molecules form the second partial beam 32, which is shown in dotted lines here and below.

Charged particles of a certain kind are deflected according to the dotted line of the first sub-beam 30 and are guided to the analyzer unit 28 . It is these particles that are to be detected by the analyzer unit 28 . In this context, the particles of the second partial beam 32 form dirt particles and are not desired in the area of the analyzer unit 28 .

It goes without saying that typical particle beams 26 from gas analysis systems usually have more than two components, ie more than two different types of molecules. Consequently, not only two discrete partial beams 30, 32 are typically formed, but actually a whole fan of partial beams is formed. For the most part, this fan contains dirt particles, that is to say partial beams which should not be guided to the analyzer unit 28 . The goal is to guide as many dirt particles and as many second partial jets as possible, which include dirt particles, into a pump-active area 34 of the vacuum pump 22 . As a result, the dirt particles are actively removed and contamination of the first partial beam 30 and of the area of the analyzer unit 28 is reduced.

The active pumping area 34 is formed here at least by a first turbo rotor disk 36 in the pumping direction of the vacuum pump 22 and specifically by its rotor blades arranged distributed over the circumference. The vacuum pump 22 includes, for example, a plurality of turbo rotor disks 36, generally turbo stages, and a Holweck stage 38.

In the embodiment of 6 the second partial beam 32 is guided parallel to the rotor axis 40 of the vacuum pump 22 and parallel to its pumping direction into the active pumping region 34 . In the embodiment of 7 the second partial jet 32 is, however, guided obliquely to the rotor axis 40 into the active pumping area 34 . In 7 an aperture 42 for the first partial beam 30 is also indicated, which is connected downstream of the deflection device 24 and further improves the selection of the partial beams.

Especially with regard to the Figures 6 and 7 an embodiment of a vacuum system according to the invention that is not shown separately but is disclosed here can also be described, in which no deflection device is provided and in which no partial beams are formed. The jet 26 in particular is guided into the active pumping region of the pump stage 36, with the path of the jet 26 corresponding in particular to that of the second partial jet 32 or the dotted arrow. The particles of the beam 26 or 32 fed into the pump stage 36 are captured directly by the pump stage 36 and advantageously removed, regardless of whether parts of the beam 26 were previously deflected.

In 8 1 shows a gas analysis system 20 with a multi-stage vacuum pump 22, with the jet 26 or the partial jets 30 and 32 being guided through an intermediate stage region 44. In this case, the second partial jet 32 is guided into an active pumping region of a turbo rotor disk 36 arranged downstream of the intermediate stage region 44 in the pumping direction.

The common beam 26 is guided into the interstage region 44 through a first intermediate port 46 . The first split beam 30 exits the interstage region 44 through a second intermediate port 48 .

The deflection device 24 is arranged or active in the intermediate stage area 44 and causes the splitting of the common beam 26 into the partial beams 30, 32 there.

In the embodiment of 8 the intermediate port 48 is connected to a chamber 50 . The analyzer unit 28 is located in this chamber 50 and the first partial beam 30 is guided through the intermediate connection 48 to the analyzer unit 28 . The chamber 50 is also connected to an inlet 52 of the vacuum pump 22 , in this embodiment another set of turbo rotor disks 54 are arranged at the inlet 52 and evacuate the chamber 50 .

The turbo rotor disks 36 and 54 are arranged on a common rotor shaft 56, on which a Holweck rotor of the Holweck pump stage 38 is also located in this example.

In this embodiment, the vacuum pump 22 is used on the one hand for improved separation of the partial beams 30 and 32 by actively removing the molecules of the second partial beam 32 and thus cleaning the first partial beam 30 to a certain extent. On the other hand, the vacuum pump 22 also serves to evacuate the chamber 50 in which the analyzer unit 28 is located. This results in an extremely compact design with advantageous analysis accuracy.

In the embodiment shown, the common jet 26 and the first partial jet 30 are also aligned at an angle with respect to the rotor axis or the rotor shaft 56 . Out of 8 it follows that this is also beneficial to the compact design.

In general and using the example of 8 It is clearly understandable that the common particle beam 26 can also include molecules that are more heavily charged and/or lighter than those of the first partial beam 30. In general, the common beam 26 can therefore include molecules that are deflected even more strongly than the first partial beam 30 A resulting third partial beam, not shown in the figures for the sake of clarity, is guided by the deflection device 24 ie counter to the pumping direction onto the last of the turbo rotor disks 54 in the pumping direction. This third partial beam is thus also guided to a pump-active region, but unlike the second partial beam 32, it is not in the pumping direction but counter to the pumping direction. Nevertheless, the relevant turbo rotor disk 54 or its rotor blades gives the molecules of the third partial jet a preferred direction in the pumping direction, so that these molecules are also actively discharged. A collision with the molecules of the first partial beam 30 is possible with these molecules. Nevertheless, the overall probability is reduced that the molecules of the third partial beam will emerge through the intermediate connection 48 or reach the analyzer unit 28 . The analysis result is thus also improved in relation to the third partial beam.

In principle, the third partial beam can also be guided onto a stator disk which is arranged downstream of the last of the turbo rotor disks 54 . In this context it should be mentioned that in Figures 6 to 14 no stator disks are shown, but that one is generally advantageously associated with, in particular downstream of, a respective turbo rotor disk. A stator disk as a disk on which the third partial beam impinges is also fundamentally advantageous in this context, although it does not have an active effect either. Because its the intermediate level The surface facing 44 provides an advantageous desorption direction distribution for a particle adhering thereto, with a high probability of desorption with a moving component in the pumping direction.

As already indicated, in practice numerous further partial beams are formed between the first partial beam 30 and the second partial beam 32 on the one hand and between the first partial beam 30 and the third partial beam described above, which are essentially aligned in a fan shape. Some of these partial beams land on passive components, in particular on the inside wall of a housing. These molecules desorb from the inner wall of the housing with a statistical directional distribution, which is generally unfavorable with regard to the goal of allowing as few dirt particles as possible to reach the analyzer unit 28 . Consequently, it is important to guide as many partial jets and as many molecules as possible that are different from the first partial jet 30, ie as many dirt particles as possible, to a pumping-active area of the vacuum pump 22, in particular to the turbo rotor blades.

The embodiment of 9 is the one who 8 overall similar, but is distinguished by the fact that two deflection devices 24 are provided in the intermediate stage area 44, in contrast to the exemplary single deflection device 24 of the embodiment of FIG 8 .

A first deflection device 24 in the direction of the beam 26 separates the partial beams 30 and 32 . The downstream deflection device 24, on the other hand, is only used for further deflection or further cleaning of the first partial beam 30. In principle, different arrangements of deflection devices are possible.

The fields of the two deflection devices 24 of the embodiment of 9 penetrate the rotor of the vacuum pump 22 and its rotating parts to a significantly lesser extent than the field of the deflection device 24 of the embodiment the 8 . This embodiment therefore results in significantly lower eddy current losses and thus less heating of the rotor.

In 10 is a vacuum pump 22, for example that of the embodiment of FIG 8 , shown in cross-section, the cutting plane being oriented perpendicularly to a rotor shaft 56 and, in particular, being arranged at the axial height of an intermediate stage region 44 . A first intermediate terminal 46 and a second intermediate terminal 48 are provided on the interstage region 44 . These are designed separately from one another and are spaced apart in the circumferential direction in relation to the rotor shaft 56 . A housing wall 58 of the vacuum pump 22 extends in the circumferential direction between the intermediate connections 46 and 48. A deflection device 24 is effective between the housing wall 58 and the rotor shaft.

The intermediate connections 46 and 48 are arranged opposite one another, namely in such a way that a connecting line runs past the rotor shaft 56 off-center.

A ray 26 is indicated by a line shown here as a continuous line. This is because, due to the selected perspective, the first partial beam 30 and the second partial beam 32 are not separately visible here, but lie on top of one another. It goes without saying, however, that the beam alignment selected here, with the beam plane parallel to the rotor axis or to the rotor shaft 56, is exemplary.

The common beam 26 enters the intermediate stage area 44 through the first intermediate connection and reaches the effective area of the deflection device 24. There the beam 26 is divided into the partial beams 30, 32, with the first partial beam 30 passing through the second intermediate connection 48 from the intermediate stage area 44 is led out.

The second partial jet 32 is guided onto the active pumping area of the visible turbo rotor disk 36, specifically onto the area swept by the plurality of rotor blades 60. The direction of rotation of the rotor shaft 56 or of the turbo rotor disk 36 preferably runs clockwise here.

11 12 shows a vacuum pump 22 having intermediate ports 46 and 48 at an interstage region 44. Each intermediate port 46 includes a flange 62, 64, respectively, for sealingly connecting the intermediate ports 46, 48 to other components. The flange 62 has a flange plane 66 which runs at an angle to the rotor axis 40 . The flange 64 also has a flange plane 68 which is oriented at an angle to the rotor axis 40 .

The intermediate connections 46 and 48 are arranged in such a way that a straight line cannot be drawn through the intermediate connections, that is, the intermediate connections are not optically transparent.

The intermediate terminals 46 and 48 are arranged in an arrow shape in this embodiment. Typically, possible angles of the intermediate ports and/or flange planes with respect to the rotor axis will correlate with those of jets 26 and 30. However, the angles of the intermediate connections and/or flange planes can also lie in a significantly wider angle range, since the actual deflection can take place in the vicinity of the connection plane, and a largely free choice of angle is therefore possible.

The vacuum pump 22 has an inlet 52 . This can be connected to a chamber, for example, also via a flange. In this case, the flange plane can, for example, run perpendicularly to the rotor axis 40 or likewise run at an angle. For example, the flange plane of the inlet 52 can also be aligned parallel to that of the flange 64, so that the pump 22 with the connections 48 and 52 can advantageously be connected to a chamber housing.

In 12 a rotor shaft 56 with rotor blades 60 of a turbo rotor disk is shown in cross section. A direction of rotation is indicated counterclockwise. Differently aligned second partial beams 32 are indicated by arrows. The reference to second partial beams 32 is here and in the following by way of example and chosen to facilitate the connection to the above-described examples with a deflection device. It is understood that with reference to the Figures 12 to 14 Possibilities of beam alignment illustrated are also valid for a beam in general, regardless of whether it was previously separated and/or deflected.

An entry point into the active pumping area is in 12 each indicated by the arrow end of the dotted arrows. A rotor blade 60 is shown precisely at a rotational position corresponding to the entry points for the purpose of illustration. The second partial beam 32.1 is guided into the pump-active region in such a way that at the point of entry the partial beam 32.1 has a direction that is directed inwards. The second partial beam 32.2 is aligned tangentially with respect to the rotor shaft 56 at the entry point. The partial beam 32.3 is directed outwards at the entry point. In other words, the partial jet 32.1 enters the active pumping area before it passes the rotor shaft 56 or a point closest to the rotor axis. The partial jet 32.3, on the other hand, has passed the rotor shaft 56 before entering the active pumping area. The partial jet 32.2 enters the active pumping area at the point where it passes the rotor shaft 56.

13 12 illustrates further options for aligning a beam, in particular a second partial beam, which illustrate a different perspective and in this respect independently or in combination with the alignments according to FIG 12 are applicable.

In 13 several rotor blades 60 are shown in simplified form in a row, with one direction of rotation being indicated by an arrow and running to the right in the plane of the drawing. The rotor blades 60 have an angle of attack 69 in relation to the rotor axis 40 .

The second partial beams 32 can be arranged differently in relation to the rotor axis. For example, the partial jet 32.4 is aligned parallel to the rotor axis and is generally aligned steeper than the angle of attack of the rotor blades. The direction of the second partial jet 32.5 corresponds to that of the rotor blades 60, ie it is adjusted accordingly. The second partial jet 32.6, on the other hand, is set flatter than the rotor blades 46. Not shown, but also possible, is co-rotating beam alignment, ie beam alignment with a directional component in the direction of rotation.

In 14 , which indicates a cross-section of the rotor or the rotor shaft 56, a radial extension 70 of a rotor blade 60 is shown, which in operation rotates about the rotor axis, which is shown in 14 perpendicular to the image plane. The rotor blade 60 extends from a radially inner end defined by a rotor core, a rotor shaft 56 and/or a blade root to a radially outer end. The radial extension 70 forms an active pumping area of the rotor blade 60 or a turbo rotor. Advantageously, the second partial jet 32 can be guided onto a radial area 72 of the rotor blades 60, which is spaced from the radially inner end and/or from the radially outer end of the rotor blades by at least a quarter of the radial extent. In particular, the second partial jet 32 can be guided onto the rotor blades 60 approximately radially in the middle or approximately at one third of the radial extent measured from the radially outer end of the rotor blades.

It is thus clearly understandable that the dirt particles or those molecules in particular that are not intended to be fed to the analyzer unit are advantageously removed by the invention. In general, the beam alignment according to the invention enables a particularly high capture probability for the particles of the beam that is guided into the active pumping region, in particular the second partial beam, and in particular for those particles that do not belong to the first partial beam. In this case, the at least essentially entire suction capacity of the pump stage, in particular the turbo rotor disk, comes into play, in whose active pumping area the jet is guided. The active pumping area is advantageously arranged close to the deflection device and thus at the location at which the partial beams are separated. Thus conductance losses between this location and the active pumping area are small. In the prior art, additional deflections of the dirt particles on their way into the vacuum pump sometimes had to be accepted, which is generally associated with losses in conductance. As a result, the invention makes it possible to remove a particularly large proportion of dirt particles in a particularly effective manner and thus in particular to improve the accuracy of the analysis.

Reference character list

111

turbomolecular pump

113

inlet flange

115

pump inlet

117

pump outlet

119

Housing

121

lower part

123

electronics housing

125

electric motor

127

accessory port

129

data interface

131

power connector

133

flood inlet

135

sealing gas connection

137

engine compartment

139

coolant connection

141

bottom

143

screw

145

bearing cap

147

mounting hole

148

coolant line

149

rotor

151

axis of rotation

153

rotor shaft

155

rotor disk

157

stator disc

159

spacer ring

161

rotor hub

163

Holweck rotor sleeve

165

Holweck rotor sleeve

167

Holweck stator sleeve

169

Holweck stator sleeve

171

Holweck fissure

173

Holweck fissure

175

Holweck fissure

179

connecting channel

181

roller bearing

183

permanent magnet bearing

185

injection nut

187

disc

189

mission

191

rotor-side bearing half

193

stator bearing half

195

ring magnet

197

ring magnet

199

bearing gap

201

carrier section

203

carrier section

205

radial strut

207

cover element

209

support ring

211

mounting ring

213

disc spring

215

Emergency or catch camp

217

motor stator

219

space

221

wall

223

labyrinth seal

20

gas analysis system

22

vacuum pump

24

deflection device

26

particle beam

28

analyzer unit

30

first partial beam

32

second partial beam

34

pumping area

36

turbo rotor disks

38

Holweck level

40

rotor axis

42

cover

44

Intermediate area

46

first intermediate connection

48

second intermediate connection

50

chamber

52

inlet

54

turbo rotor disks

56

rotor shaft

58

housing wall

60

rotor blade

62

flange

64

flange

66

flange level

68

flange level

69

angle of attack

70

radial extension

72

radial range

Claims (15)

1. A vacuum system (20), in particular a mass spectrometry system, comprising:

   a vacuum pump (22) having a pump-active region (34) in which a gas can be conveyed by means of an active pump element (36), and

   a device for generating a beam (26, 32) of particles,

   characterized in that
   the beam (26, 32) is guided into the pump-active region (34).
2. A vacuum system (20) in accordance with claim 1,

   comprising a deflection device (24) by means of which the beam (26) can be deflected such that different components of the beam (26) are deflected differently so that at least a first and a second part beam (30, 32) can be formed,

   wherein the second part beam (32) is guided into the pump-active region (34),

   and/or wherein the beam, in particular the second part beam (32), is guided into the pump-active region (34) with at least one directional component in the pump direction.
3. A vacuum system (20) in accordance with claim 2,
   wherein the first part beam (30) is not guided into the pump-active region (34), and/or wherein the first part beam (30) is guided to a region outside the vacuum pump (22).
4. A vacuum system (20) in accordance with at least one of the preceding claims,

   wherein a pump direction and/or a rotor axis (40) of the active pump element (36) and/or of the vacuum pump (22) is/are oriented obliquely with respect to a direction of the beam (26), in particular before passing through a deflection device (24),

   in particular wherein an angle between a pump direction and/or a rotor axis of the active pump element and/or of the vacuum pump and a direction of the beam (26) is in the range from 40° to 60°.
5. A vacuum system (20) in accordance with at least one of the claims 2 to 4, wherein a pump direction and/or a rotor axis (40) of the active pump element (36) and/or of the vacuum pump (22) is/are oriented obliquely with respect to a direction of the first and/or the second part beam (30, 32) after passing through the deflection device (24).
6. A vacuum system (20) in accordance with at least one of the preceding claims,

   wherein the vacuum pump (22) has at least two pump stages (36, 54), wherein an intermediate stage region (44) is arranged between the pump stages (36, 54),

   wherein the beam is guided through the intermediate stage region (44) and/or

   is guided into a pump stage (36) which is arranged downstream of the intermediate stage region (44) in the pump direction,

   in particular wherein a first part beam (32) is guided out of the vacuum pump (22) after passing through the intermediate stage region (44).
7. A vacuum system (20) in accordance with claim 6,
   wherein, at the intermediate stage region (44), the vacuum pump (22) has a first intermediate connection (46) for the entry of the beam (26) into the intermediate stage region (44) and a second intermediate connection (48) for the exit of a first part beam (30) from the intermediate stage region (44).
8. A vacuum system (20) in accordance with claim 7,

   wherein the intermediate connections (46, 48) are arranged at least substantially disposed opposite one another,

   and/or wherein the intermediate connections (46, 48) are formed separately from one another and/or are arranged separately and spaced apart in the peripheral direction.
9. A vacuum system (6) in accordance with claim 2 and at least one of the claims 6 to 8,
   wherein the deflection device (24) is effective and/or arranged in or at the intermediate stage region (44).
10. A vacuum system (20) in accordance with at least one of the preceding claims,
    wherein the beam (26, 32) is oriented off-center with respect to a rotor axis (40) of the vacuum pump (22) and/or is guided past a rotor core, in particular a non-pump-active rotor core.
11. A vacuum system (20) in accordance with at least one of the preceding claims,
    wherein the beam (26, 32) is guided into the pump-active region (34) in a direction supporting the pumping effect, in particular in an opposite sense to a direction of rotation of a turbo-rotor disk (36).
12. A vacuum system (20) in accordance with at least one of the claims 2 to 11,
    wherein the vacuum pump (22) is of multi-stage design, the second part beam (32) is guided into a pump stage (36) and the first part beam (30) is guided into a chamber (50) which is connected to a further pump stage (54) of the vacuum pump (22).
13. A vacuum pump (22), in particular a turbomolecular vacuum pump, comprising at least two pump stages (36, 54), wherein an intermediate stage region (44) is arranged between the pump stages (36, 54), wherein, at the intermediate stage region (44), the vacuum pump (22) has a first intermediate connection (46) for the entry of a particle beam (26) into the intermediate stage region (44) and a second intermediate connection (48) for the exit of a particle beam (30) from the intermediate stage region (44),

    wherein the incoming particle beam (26) can be guided through the intermediate stage region such that the particle beam (30) exiting from the second intermediate connection (48) exits again from the intermediate stage region (44) as a first part beam (30) of the incoming particle beam (26) and such that a second part beam (32) of the incoming particle beam (26) is guided into a pump-active region (34) of the vacuum pump, wherein the intermediate connections (46, 48) are separated and spaced apart from one another in the peripheral direction,

    in particular wherein exactly two intermediate connections (46, 48) are provided at the intermediate stage region (44).
14. A vacuum pump (22) in accordance with claim 13,
    wherein the intermediate connections (46, 48) are arranged such that no straight line can be laid through the intermediate connections.
15. A gas analysis method, in particular a mass spectrometry method, in particular performed using a vacuum system (20) in accordance with any one of the claims 1 to 12 and/or using a vacuum pump (22) in accordance with claim 13 or claim 14, in which

    a vacuum pump (22), in particular the vacuum pump in accordance with claim 13 or claim 14, is provided with a pump-active region (34) in which a gas can be conveyed by means of an active pump element (36),

    a beam (26) of particles to be analyzed is generated, and

    the beam (26) is deflected by means of a deflection device (24) such that different components of the beam (26) are deflected differently so that at least a first and a second part beam (32) are formed, wherein the second part beam (32) is guided into the pump-active region (34) of the vacuum pump (22), and wherein the first part beam (30) is not guided into the pump-active region (34) of the vacuum pump (22), but is analyzed.

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