Vacuum pump and method for monitoring a vacuum pump

Abstract

The present invention relates to a vacuum pump or a vacuum system including at least one vacuum pump, wherein an inertial measurement unit is assigned to the vacuum pump, the inertial measurement unit including at least one inertial sensor designed to acquire the motion and / or orientation of the vacuum pump, and to provide associated measurement data and / or information obtained by evaluating the measurement data.

Description

Technical Field

[0001] The present invention relates to a vacuum pump, in particular to a turbomolecular vacuum pump. The present invention also relates to a vacuum system having at least one vacuum pump, in particular to a turbomolecular vacuum pump. The present invention also relates to a method for monitoring a vacuum pump or a vacuum system comprising at least one vacuum pump. Background Art

[0002] In the context of the present disclosure, a vacuum system is understood to be a device consisting of, for example, one or more vacuum pumps and one or more vacuum chambers or cavities to be evacuated. Such a device is sometimes also referred to as a pumping station.

[0003] In many technical fields, and also in the field of vacuum technology, condition monitoring, i.e. the acquisition and evaluation of condition information about individual components of a vacuum system or an individual vacuum pump, is becoming increasingly important in practice. The goals associated with condition monitoring are extremely diverse and range, for example, from increasing the service life of the vacuum pump, to simplifying and improving the maintenance and repair of vacuum pumps and vacuum systems, to improving the operator's possibilities of use and increasing customer friendliness by providing information about the vacuum pump and the vacuum system. In this context, the operator of a vacuum pump or a vacuum system including a vacuum pump is generally understood to be a customer who purchased the vacuum pump from a pump manufacturer. Against this background, condition monitoring can be important in terms of possible disputes between pump manufacturers and operators, for example due to warranty claims and complaints. Summary of the invention

[0004] The object of the present invention is therefore to create a device for condition monitoring of a vacuum pump or a vacuum system comprising at least one vacuum pump which is as simple, reliable and cost-effective as possible.

[0005] In the vacuum pump according to the invention, and in the vacuum system according to the invention comprising at least one vacuum pump, according to the invention, an inertial measurement unit is respectively provided which is assigned to the vacuum pump, the inertial measurement unit comprising at least one inertial sensor which is designed to detect the movement of the vacuum pump and / or the orientation of the vacuum pump and to provide measurement data related thereto and / or to provide information obtained by evaluating these measurement data.

[0006] In the professional field, an inertial measurement unit is also called IMU (Inertial Measurement Unit), which is a spatial arrangement of multiple inertial sensors. An inertial sensor can be, for example, an acceleration sensor or a rotational speed sensor. A rotational speed sensor is also called a gyroscope sensor or a gyroscope sensor. Today, such inertial sensors are used in large quantities and are available on the market in a variety of designs and qualities.

[0007] Acceleration sensors usually provide linear acceleration values ​​for a translational movement relative to a translation axis. Rate sensors usually provide angular velocity relative to an axis of rotation. By integrating the acceleration values ​​of an acceleration sensor twice, path information can be obtained, i.e. information about the path traversed relative to a reference orientation or reference position. By integrating the angular velocity of a rate sensor once, rotation angle information can be obtained, i.e. information about the rotation angle traversed respectively relative to a reference orientation or reference orientation. For this reason, inertial sensors are often used for navigation tasks, for example for drones. However, inertial sensors are also widely used in other applications, for example as sensors in mobile phones or for measuring vibrations on buildings and machines.

[0008] The inertial sensors available on the market can be designed so that they directly provide acceleration signals or velocity signals (i.e. raw measured values ​​or raw data), which therefore do not require additional preprocessing or processing in order to obtain information about the corresponding acceleration or velocity directly from the inertial sensor itself. Therefore, the inertial measurement unit used according to the invention, which can include one or more inertial sensors, can directly provide one or more acceleration or velocity signals. However, the inertial measurement unit can also be designed and equipped with suitable electronic components for this purpose, so that the "raw data" or the information obtained therefrom can be subjected to any signal preprocessing and processing and storage in principle.

[0009] In the context of the present disclosure, the "position" of an object, in particular of a vacuum pump, is to be understood as its position and orientation in a corresponding coordinate system. A translation of an object changes the position of the object, and a rotation of an object changes the orientation of the object. The movement of an object may comprise only a translation relative to one, two or three axes of translation, or only a rotation relative to one, two or three axes of rotation, or a translation and a rotation, in particular relative to all six possible degrees of freedom.

[0010] Furthermore, within the scope of the present disclosure, a “movement” of an object, in particular a “movement” of a vacuum pump, is to be understood as a vibration or oscillation of the vacuum pump.

[0011] The movement of an object, in particular the movement of a vacuum pump, also causes sound emissions in the vicinity of the object. Vibrations or oscillations generally also result in undesired emission of sound levels. With the aid of a sound pressure sensor or a sound level frequency sensor, in particular with the aid of a microphone, the resulting sound pressure or sound level or sound spectrum of the object can be acquired. Within the scope of the present disclosure, for the sake of simplicity, the general term "inertial sensor" also applies synonymously to sound pressure or sound level sensors, even if they are not mentioned again separately as specific embodiments.

[0012] According to the invention, the measurement data provided by at least one inertial sensor of an inertial measurement unit assigned to the vacuum pump, in particular integrated into the vacuum pump, can be raw measurement data, in particular acceleration or velocity signals generated directly by the inertial sensor. The raw measurement data can be stored, for example, in the vacuum pump and can therefore be available, for example, for subsequent evaluation. Thus, no immediate signal processing, in particular no real-time signal processing, is necessary. Alternatively or additionally, the provided measurement data can also be preprocessed measurement data, which are obtained, for example, by preprocessing or processing from the signal provided directly by the inertial sensor with the aid of electronic components belonging to the inertial measurement unit.

[0013] In a preferred embodiment of the invention, the inertial measurement unit assigned to the vacuum pump, preferably integrated in the vacuum pump, therefore comprises one or more inertial sensors which directly provide an acceleration signal or a velocity signal, respectively.

[0014] In the monitoring method according to the invention, before, during and / or after the operation of a vacuum pump or a vacuum system, the movement of the vacuum pump and / or the orientation of the vacuum pump and / or the movement of the vacuum system are detected by means of an inertial measurement unit of the vacuum pump and measurement data relating thereto and / or information obtained by evaluating these measurement data are provided. As already mentioned above and below based on the vacuum pump according to the invention and the vacuum system according to the invention, these measurement data can be raw measurement data of an inertial sensor and / or preprocessed measurement data.

[0015] Monitoring according to the invention comprises in particular the acquisition or detection or identification of the state or state changes of the vacuum pump and / or the vacuum system, and the provision and / or storage of state information relating thereto.

[0016] According to the invention, it is possible, but not mandatory, to evaluate the measured data during operation and, as a reaction to the evaluation, to intervene in the current operation of the vacuum pump and / or the vacuum system. Thus, according to the invention, it is possible, for example, to store only the measured data or the information obtained by the evaluation of the measured data during operation of the vacuum pump and to perform the evaluation at a subsequent point in time, for example in the case of repair or in regular maintenance.

[0017] According to the invention, an inertial measurement unit can be integrated into a vacuum pump. Optionally, the inertial measurement unit can be integrated into an external accessory that can be detachably mounted on the pump. For example, the inertial measurement unit can be integrated into an electronics housing of the vacuum pump, which is arranged outside the actual pump housing of the vacuum pump and, in particular, is detachably connected to the vacuum pump. Preprocessing or evaluation of the measurement data can take place in the aforementioned accessory, in the electronics housing or in the drive electronics of the vacuum pump. The drive electronics can be located in the aforementioned electronics housing. That is, as an accessory and also as an integrated solution, the inertial measurement unit with a plug connector can be connected to a display, output, evaluation, data forwarding or other data processing unit by wire or via a radio connection.

[0018] Other possible embodiments of the present invention, namely the vacuum pump according to the present invention, the vacuum system according to the present invention and the monitoring method according to the present invention are described below.

[0019] According to one embodiment of the invention, a control device connected to the inertial measurement unit is assigned to the vacuum pump, the control device being designed to evaluate measurement data of the inertial measurement unit.

[0020] According to a further embodiment of the invention, an output device is assigned to the vacuum pump, via which the measurement data of the inertial measurement unit and / or the information obtained by evaluating these measurement data can be output or retrieved. The output device can be, for example, a data interface of the vacuum pump or an accessory connection of the vacuum pump, referred to as an accessory port. Alternatively or additionally, the output can also be wireless.

[0021] Furthermore, it can be provided according to an embodiment of the invention that a storage device is assigned to the vacuum pump, which storage device is designed for storing measurement data of the inertial measurement unit and / or information obtained by evaluating these measurement data.

[0022] As already mentioned in the context of the inertial measurement unit, the control device and / or the storage device can be integrated in the vacuum pump, in the electronic component housing of the vacuum pump, in an accessory of the vacuum pump or connected to a data storage and processing device at a possibly non-local location via data forwarding. Thus, the invention can utilize infrastructures such as edge computing, cloud computing and / or fog computing.

[0023] The control device can be integrated in the inertial measurement unit. Alternatively, it is possible that the inertial measurement unit can form a component of the control device. The storage device can be integrated in the control device or the inertial measurement unit, or can be arranged separately from them.

[0024] The inertial measurement unit and / or the control device and / or the memory device can be integrated into the drive electronics of the vacuum pump.

[0025] Preferably, the inertial measurement unit comprises a spatial arrangement of a plurality of inertial sensors, wherein in particular the inertial measurement unit comprises: two or three acceleration sensors, to which one of three translation axes of the vacuum pump extending in pairs perpendicular to each other is respectively assigned; and / or two or three rotational speed sensors, to which one of three rotational speed sensors extending in pairs perpendicular to each other is respectively assigned.

[0026] The inertial measurement unit may be designed as a MEMS (Mikro-Elektro-Mechanisches System), or a component of a MEMS, or may be designed as an optical system, for example.

[0027] As mentioned above, the structure and working mode of such an inertial measurement unit and other specific designs of the inertial measurement unit or IMU are well known to those skilled in the art, and therefore, there is no need to discuss them in more detail.

[0028] According to the invention, the inertial measurement unit can in principle be mounted at any position of the vacuum pump. Depending on the specific design of the vacuum pump and on the basis of the respective application, one or a specific position of the vacuum pump can prove to be particularly advantageous for arranging the inertial measurement unit. According to the invention, a possible position for arranging the inertial measurement unit is the vacuum sleeve of the vacuum pump. Such a vacuum sleeve is known in principle. The vacuum sleeve of the vacuum pump can be formed, for example, by a circuit board. According to the invention, the inertial measurement unit can be arranged on such a circuit board forming the vacuum sleeve. In this way, an existing vacuum pump can be retrofitted with an inertial measurement unit at relatively little expense and at relatively low cost. Another advantage is that for such an arrangement of the inertial measurement unit, the mass production of the vacuum pump only needs to be relatively slightly changed.

[0029] However, it is also entirely possible to apply the inertial measurement unit or any other sensor (e.g. a temperature measuring sensor) to a separate printed circuit board which is fixed inside the pump. This printed circuit board can then be connected to another printed circuit board or a vacuum jacket or a printed circuit board as a vacuum jacket, for example by means of a cable in a detachable manner (e.g. by means of a plug connection), in a limited detachable manner (e.g. by means of a clamping connection) or in a non-detachable manner (e.g. by welding).

[0030] According to an embodiment of the monitoring method of the present invention, it is provided that: one or more state information of the vacuum pump and / or the vacuum system is determined based on the measurement data. According to the present invention, the state information or each state information can be output via an output device of the vacuum pump and / or stored in a storage device of the vacuum pump.

[0031] The state information can be, for example, only a "snapshot" of the vacuum pump or one or more predefined components of the vacuum pump. Alternatively, the state information can reflect the temporal behavior or temporal development of the vacuum pump or the corresponding components, in particular, one or more parameters or signals of the vacuum pump or the associated components, respectively. In this case, the inertial measurement unit repeatedly provides measurement data with a substantially arbitrary, predefined or predefinable temporal resolution.

[0032] According to a possible embodiment of the invention, the orientation of the vacuum pump in space and / or the orientation of the vacuum pump relative to one or more other components of the vacuum system is determined as status information of the vacuum pump and / or the vacuum system.

[0033] In this context, the control device of the vacuum pump can be designed to allow or prohibit the start of operation of the vacuum pump according to the determined orientation of the vacuum pump. Therefore, the vacuum pump can determine by itself whether the vacuum pump is oriented to not allow operation, and the user cannot accidentally initiate an unallowed start of operation.

[0034] Alternatively or additionally, the determined orientation of the vacuum pump is taken into account when evaluating the frequency spectrum related to the vibrations of the vacuum pump and / or the vacuum system. In this case, use can be made of the fact that the vibration behavior of the vacuum pump is related to the orientation of the pump in space. As a result, the vibration behavior can be evaluated and assessed specifically depending on the determined orientation of the vacuum pump.

[0035] According to another embodiment of the invention, the orientation of the vacuum pump is stored only in special, preset events. The determined orientation is therefore not actively used in the following aspects: actively intervening in the currently ongoing operation of the pump according to the determined orientation, but the information is simply stored for passive use of the information. An event in the sense of this embodiment can be, for example, the powering on of the vacuum pump, the start of operation of the vacuum pump, the start of operation of one or more preset components of the vacuum system including the vacuum pump (in addition to the vacuum pump itself), or a change in the installation position of the vacuum pump. The stored information can then be taken into account for evaluation at a subsequent point in time, for example in the case of maintenance or complaints.

[0036] According to another embodiment of the invention, the vacuum pump comprises a rotor which is rotated by means of a drive motor during operation, wherein an imbalance of the rotor and / or a vibration state of the vacuum pump and / or the vacuum system are determined as state information of the vacuum pump and / or the vacuum system.

[0037] Preferably, the rotor imbalance and / or the vibration state are determined repeatedly during operation of the vacuum pump. In this way, for example, the time behavior of the rotor imbalance or the vibration state, in particular the time development of the vibration behavior of the vacuum pump, can be monitored and recorded, i.e. saved for subsequent evaluation.

[0038] Here, for example, at least one measure of the time change of the rotor imbalance and / or vibration state, in particular the rate of change, can be determined. In particular, this is done with reference to a corresponding basic state of the rotor imbalance and / or vibration state determined at a constant operating speed of the rotor.

[0039] Determining the base state can be performed during one or more one-time events, such as final manufacturing testing of the vacuum system, initial commissioning, or also during the acceptance or first production start-up phase of the vacuum system, so that this base state can be stored and used as a permanent reference basis for recording status information occurring during continued operation.

[0040] According to one embodiment of the invention, a reaction is triggered when a relative or absolute limit value is exceeded. In particular, a warning indication is output. The limit value is, for example, a limit value of the rotor imbalance and / or the vibration state, or a limit value of the time variation of the rotor imbalance and / or the vibration state. For example, the amplitude with respect to time can be determined, and from the support point a compensation curve can be derived in a computational manner, the local slope of which is a measure of the time variation of the vibration manifestation, which compensation curve can be evaluated or analyzed again in time. In addition, the support point can be evaluated in detail with the help of statistical methods, i.e., for example, trend or distribution analysis, stability or outlier analysis.

[0041] Optionally or additionally, according to another embodiment, when approaching relative or absolute limit values ​​of the rotor imbalance and / or vibration state, or when approaching relative or absolute limit values ​​of the time change of the rotor imbalance and / or vibration state, an estimate of the next maintenance date of the vacuum pump is calculated, or the currently preset maintenance interval is adjusted.

[0042] According to another embodiment of the invention, a measure of the utilization reserve of the vacuum pump is calculated, for example relative to an output value of 100% set when the vacuum pump is delivered, from which 100% output value is counted back during the operation of the vacuum pump. Furthermore, alternatively or additionally, a recommended value for the time until the next maintenance of the vacuum pump can be calculated and made available via a data interface or output directly via an output unit. This is done in particular taking into account the usage profile of the vacuum pump to date, and therefore for each individual vacuum pump individually.

[0043] When determining the rotor imbalance and / or the vibration behavior, the evaluation of the measurement data of the inertial measurement unit can be limited to movements in the radial direction (relative to the axis of rotation of the rotor).

[0044] The determination of the rotor imbalance and / or the vibration state is therefore a powerful diagnostic tool, with the aid of which operators and manufacturers of vacuum pumps are provided with numerous options for checking and monitoring the functionality and operational safety of the vacuum pump.

[0045] According to the invention, the evaluation of the determined rotor imbalance and / or the determined vibration behavior can be carried out in the sense that a parameter of the vacuum pump is evaluated as a change indicator. In this context, the parameter, i.e., for example, the rotor imbalance, can form one of preferably a plurality of predefined KPIs (KPI=Key Performance Indicator). In particular, the parameter can form a so-called health KPI, which allows the current functional state of the vacuum pump to be evaluated.

[0046] According to the invention, the rotor imbalance can be evaluated by means of the first harmonic corresponding to the frequency of the operating speed of the rotor. Higher harmonics can also be used for evaluating the rotor imbalance. However, this is not absolutely necessary.

[0047] In evaluating the measured data, according to the invention, methods from the field of Fourier analysis, such as FFT (FFT = Fast Fourier Transform), can be used. For example, such an FFT can be created based on a digital time signal. Furthermore, according to the invention, special methods of digital signal processing can be used in the evaluation of the measured data, such as the Goelzer algorithm ( -Algorithmus) or another type of discrete Fourier transform. The Golzer algorithm allows the calculation of individual discrete spectral components of the spectrum. In this way, for example, so-called operating peaks can be taken into account when evaluating the measurement data.

[0048] With regard to signal processing when evaluating the measured data, the invention enables a relatively simple process which, in particular, does not require continuous tuning of the frequency and does not require the use of so-called frequency filter circuits.

[0049] The above-mentioned possibilities for evaluating the measurement data can be combined with one another and are not limited to specific causes of vibrations of the vacuum pump. Vibrations of the vacuum pump can be caused, for example, by rotor imbalances, but can also be caused by external sources, for example by other pumps or components with movable parts of the corresponding vacuum system to which the vacuum pump provided with the inertial measurement unit belongs.

[0050] According to another embodiment of the present invention, the vibration state of the vacuum pump and / or the vacuum system can be determined as the state information of the vacuum pump and / or the vacuum system. In particular, a frequency spectrum of the vibration related to the vacuum pump and / or the vacuum system is determined.

[0051] In particular, vibrations of the vacuum pump are formed during operation when the vacuum pump comprises a rotor which is in rotation during operation by means of a drive motor. However, as already mentioned, the vibrations of the vacuum pump can also have other, for example external, but also other internal causes. Therefore, the present invention is not limited to such vacuum pumps which comprise a rotor which is in rotation during operation by means of a drive motor. For example, so-called screw vacuum pumps do not have a rotor which rotates during operation, but rather one or more other movable parts which implement a so-called orbital motion. The present invention can also be used in conjunction with such vacuum pumps.

[0052] As already mentioned, according to the invention, the determination of the frequency spectrum of the vacuum pump can include methods from the field of Fourier analysis, such as the so-called FFT (FFT=Fast Fourier Transform). The detection of the spectrum can be limited to individual frequencies or to a plurality of frequency bands. The storage of the determined spectrum can be limited to storing specific points, regions or sections of the spectrum, for example in this way: only a specific number of relatively highest peaks are stored.

[0053] If the vibration state of the vacuum pump and / or the vacuum system is determined as state information, in particular, it can be provided that the vibration state is determined during the acceleration of the vacuum pump, in particular, is stored. Thus, the vibration state is determined during an initial operating phase of the vacuum pump, during which the rotational speed of the rotor increases. In particular, the vibration state can also be determined after acceleration, when the rotor is running at the operating speed.

[0054] Preferably, the resonance state of the vacuum pump and / or the vacuum system is determined here, i.e. during the acceleration of the vacuum pump. The pump acts as an exciter here. How the pump and the system respond to the excitation provides information about the current resonance over a wide frequency spectrum, in particular from 0 Hz to the operating speed. For example, the information about the resonance state is provided for output to an external device, such as a system control device of the vacuum system, or is called up by an external device, in particular a system control device of the vacuum system, and in this way is provided, for example, to an operator of the vacuum system.

[0055] The above-described procedure for determining the resonance state can be used not only when the vacuum pump is accelerating, but also, conversely, at the end of a cycle or process of the vacuum system, and thus during deceleration or coasting of the vacuum pump. The method may require additional operating time, for example after the end of a predetermined process, or additional measuring time at the end of a predetermined process, in order to determine the vibration state while the rotor is still running at the operating speed, possibly with a process gas flow at least partially still active. In addition, the ventilation of the vacuum system may be delayed, in particular in an actively controlled manner, so that the vacuum pump can be optimally decelerated in order to achieve the best possible resonance measurement.

[0056] A potential advantage of measuring during inertial operation compared to determining during acceleration of the vacuum pump is that, for example, the drive motor is not running at all or is only running with a small braking power instead of at maximum power, which results in a lower potential electromagnetic and mechanical interference spectrum for the inertial measurement unit and its signal lines, which are usually arranged in close proximity to each other depending on the situation.

[0057] Another advantage is that at the end of a cycle or process, the state information is determined during a stable, thermally stable state of the vacuum pump and the vacuum system. Usually, the previous operating sequence occurs regularly and in the same way, which creates a long-term stable comparison basis for the acquired operating states. Undesirable influences or uncertainties of non-specific, rarely occurring states and their effect on the state information can be significantly reduced. For example, the "cold start" of the system, i.e. the first acceleration of the vacuum pump and the vacuum system at the beginning of an operating phase or the first operating cycle after a longer process pause, can be cited here.

[0058] Finally, the organizational advantage should be mentioned, namely obtaining possibly current status information at the end of a possibly longer run or batch, which informs the user / operator as best as possible about the remaining usage reserve before the potentially subsequently planned start of other possibly longer runs or batches.

[0059] Alternatively or additionally, according to the present invention, the operational safety and / or service life of the vacuum pump and / or vacuum system can be improved by means of the determined resonance state in the following manner: the vacuum pump and / or vacuum system outputs a warning or automatically performs rotor speed regulation at a preset time point, especially when the rotor speed approaches the resonance state. This can prevent the vacuum pump from operating in a resonance state.

[0060] According to the invention, alternatively or additionally, the determination of the vibration state of the vacuum pump and / or the vacuum system can also be used to automatically change the rotational speed of the rotor of the vacuum pump if, based on the determined vibration state, the control device of the vacuum pump or the system control device of the vacuum system detects one or more other vacuum pumps within the vacuum system that are operated at approximately the same operating speed as the vacuum pump. In this way, undesirable flutter states can be prevented.

[0061] Furthermore, according to another embodiment of the invention, the determination of the vibration state of the vacuum pump and / or the vacuum system can be used to monitor one or more predefined parameters of the vacuum pump and / or one or more signals of one or more sensors of the vacuum pump as a function of the determined vibration state. The monitoring is performed in particular with regard to the temporal behavior of the one or more parameters or the one or more signals.

[0062] Preferably, the monitoring is performed with respect to a target state of the vacuum pump and / or the vacuum system determined in a learning phase, wherein after the learning phase, the control device of the vacuum pump checks whether the monitored parameter or parameters and / or the monitored signal or signals correspond to the target state. If a deviation from the target state is detected during this check (taking into account predefined tolerances), this change in the relevant parameter or signal is evaluated and / or assessed, in particular taking into account predefined criteria.

[0063] Preferably, the above-mentioned learning for determining the target state is automatic.

[0064] According to the invention, such learning can also be performed in a completely universal manner, ie independently of the determination of the vibration state and also independently of the monitoring based thereon, in order to provide a particularly continuous comparison basis for any measurements performed by means of the inertial measurement unit, for example as described above.

[0065] According to another embodiment of the present invention, one or more special events are determined as status information of the vacuum pump and / or the vacuum system. The determined one or more events, i.e. information or data related to the one or more events, can be output via an output device of the vacuum pump and / or can be stored in a storage device of the vacuum pump.

[0066] It can be provided that the permanently determined measurement data are buffered and subsequently stored only when an event actually occurs. What is evaluated as an "event" depends on the respective application and can be predefined by specific criteria. In this context, predefined limit values ​​can be used, for example, for a vibration amplitude measured as a parameter, the exceeding of which is evaluated as an event occurrence. According to the invention, one or more limit values ​​can be assigned to any parameter or signal.

[0067] One embodiment of the invention comprises the following, the vacuum pump comprises a rotor which is in rotation during operation by means of a drive motor, and an axial displacement of the rotor between a first axial position and a second axial position is detected as a special event during operation of the vacuum pump. For example, the first axial position is a so-called pre-vacuum position of the rotor, and the second axial position is a so-called high vacuum position.

[0068] This displacement of the rotor, also called runout, is known in principle to those skilled in the art. This phenomenon observed in practice occurs in particular in hybrid-mounted rotors of turbomolecular vacuum pumps. Hybrid mounting here means that on the high vacuum side (HV side) of the pump, there is a magnetic bearing, in particular a passive, repelling radial bearing with permanent magnets, between the rotor and the stator of the pump. On the pre-vacuum side (VV side), on the other hand, the rotor is supported by means of rolling bearings, in particular ball bearings. The bearing design accordingly identifies the magnetic bearing as a floating bearing with radial action and the rolling bearing as a fixed bearing with radial and axial bearing action relative to the axis of rotation.

[0069] The cause of "rotor runout" is the heating caused by the operation of the rotor and the axial thermal expansion of the rotor along the axis of rotation of the rotor caused by the heating, which causes a change in the axial relative position between the magnetic bearing set on the rotor side and the magnetic bearing set on the stator side of the magnetic bearing between the shaft and the stator on the floating bearing side. This change leads to a change in the axial repulsive force of the magnetic bearing that is system-related and undesirable in the magnetic bearing, which leads to a sudden movement of the rotor in the direction of the high vacuum side at a certain point in time. This movement is achieved and limited by the axial backlash on the fixed bearing side that exists for technical reasons. In particular, the backlash is composed of rolling bearing clearance, in particular bearing play or running clearance, and the elasticity of other adjacent components, in particular vibration-isolating and / or vibration-damping elastomeric bearing inserts.

[0070] When cooling the rotor, a run-out back to the pre-vacuum side is also possible, in particular when the vacuum system is shut down or the vacuum pump is cooled after shutdown. The temperature that varies depending on the operating state and the resulting thermal expansion of the stator components arranged between the bearing points also influence the axial displacement of the magnetic bearing components on the floating bearing side, but usually this influence is less than that of the rotor due to the smaller temperature changes during operation. Due to the joint heating during operation, some of the expansions of the rotor and stator components can compensate for each other, but this depends largely on the material selection (e.g. the corresponding expansion coefficients) and the type of cooling device that can be provided mainly on the stator.

[0071] In particular, the event of a rotor runout can be described as a change of sign of the axial bearing load borne in the fixed bearing. This bearing load consists of the weight of the rotor, which occurs with different strengths depending on the spatial orientation or installation direction of the vacuum pump, and the axial repulsive force caused by the magnetic bearing. In extreme operating conditions, such as operation of a vacuum pump with a rotor at maximum temperature and a very well cooled stator, or in the first "completely cold" start-up of the vacuum pump at minimum temperature as another extreme, the maximum axial repulsive force of the magnetic bearing is generally greater in value than the absolute weight of the rotor. The rotor runout occurs accordingly independently of the spatial orientation of the pump during certain operating phases, in particular after a short pre-operation phase of the vacuum pump or after shutdown, usually once per phase.

[0072] During the manufacture or maintenance of the vacuum pump, the so-called "setting" of the hybrid bearing can be carried out, so that at normal temperature the direction and value of the action of the axial repulsive force are changed to the value that is optimally selected for the subsequent operation of the vacuum pump by means of a mechanical control and setting mechanism or device. In particular, this occurs by mechanically changing the axial spacing of the floating bearing and the fixed bearing on the stator side by auxiliary means, such as adding washers or adjusting preloaded, self-locking threaded adjustment elements.

[0073] The settings can be used to achieve different objectives, in particular the maximum axial bearing force should be kept low in all possible operating states in order to increase the service life of the rolling bearing, and also the aim of reliably carrying out required rotor run-outs at specific operating times, for example during warm-up.

[0074] In this context, therefore, reference is made to a “beating” of a rotor which was previously “operated on the pre-vacuum side” and which subsequently “operates on the high vacuum side”, or vice versa, respectively.

[0075] Since such rotor runouts each cause a (brief) movement of the vacuum pump, such events can be detected with the aid of the inertial measuring unit according to the invention. For example, in a subsequent evaluation it can be checked, for example, how much of the total operating time of the pump the rotor is on the pre-vacuum side and how much of the rotor is in the high vacuum position. A comparison of the rotor temperature and the temperatures of the individual or multiple pump bodies can be used to determine the bearing loads that are dominant in the respective state and are caused by the axial repulsive forces of the magnetic bearings, which are added as an additional component to the usual static and dynamic bearing loads of the rolling bearings. The point of the rotor runout can also be evaluated, in particular, a notification can be generated if maintenance for resetting or a modification of the bearing setting is required.

[0076] Alternatively or additionally, according to the invention, the movement of the vacuum pump as a whole can be detected as a special event. This movement can be analyzed, for example, with regard to the direction and value of the translation and / or rotation of the vacuum pump. The analysis of the movement of the vacuum pump can be carried out, for example, in a mobile or so-called semi-mobile vacuum system during the operation of the vacuum pump.

[0077] Due to gyroscopic forces, the speed of the rotational speed change that occurs non-coaxially with respect to the rotational axis of the rotor of the vacuum pump plays a decisive role in the radial bearing load of the rotating system (such as the vacuum pump). Therefore, the analysis of the rotational speed can be used to provide information and / or warnings about the permissible speed of the rotational speed change during the operation of the vacuum pump. Here, the permissible load and thus the speed of change can be defined in different levels depending on the direction of rotation. The information can be output for each spatial axis or also as a calculated comparison value.

[0078] In vacuum pumps with contactless magnet bearings, the consumption of radial and possibly also axial bearing clearances is usually the limiting variable for defining the permissible speed changes and translational speed changes. Especially in vacuum pumps with hybrid bearings, it is almost impossible to directly measure the safety bearing clearance during operation. Direction-dependent monitoring of the change in movement, whether rotational or translational, can provide status information as to which load range the magnet bearing is in and whether there is sufficient safety margin to store warning or error thresholds.

[0079] Other possible special events that can be determined according to the invention are changes in the installation position of the vacuum pump, so-called "shocks", which are events that cause a preset acceleration limit value to be exceeded briefly. For example, such a shock can be caused by a knock on the vacuum pump or by other mechanical actions on the vacuum system or the vacuum pump, for example by the vacuum pump or the vacuum system tipping over.

[0080] According to the invention, the measurement data and / or the information obtained from the measurement data can be used in a variety of ways and methods. For example, the data / information can be stored only in the vacuum pump, more precisely, so that only the manufacturer of the vacuum pump can access the data / information.

[0081] Optionally, the data / information can be provided to an operator of the vacuum pump or of a vacuum system comprising the vacuum pump. As already mentioned elsewhere, in practice, this operator is usually a customer of the vacuum pump manufacturer.

[0082] Generally, it can be provided according to the invention that the measured data and / or the information obtained by evaluating these measured data can only be output or called up if authorization is present. In particular, this can be done via an interface of the vacuum pump or an accessory connection of the vacuum pump. The required authorization can be done, for example, by the manufacturer of the vacuum pump. Thus, certain operators of the vacuum pump can be allowed to access data / information, while other operators can be denied access.

[0083] Alternatively or additionally, the data / information can be output to a system control of a vacuum system including the vacuum pump and / or can be called up by the system control. In this case, the data / information does not have to be accessed directly via the vacuum pump, but can be accessed via the system control, into which the vacuum pump, in particular the control of the vacuum pump, is integrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] The present invention is described below by way of example according to preferred embodiments with reference to the accompanying drawings. The accompanying drawings schematically show:

[0085] Figure 1 A perspective view showing a turbomolecular pump,

[0086] Figure 2 Show Figure 1 A view of the underside of a turbomolecular pump,

[0087] Figure 3 Shown along Figure 2 The cross section of the turbomolecular pump shown is along the section line AA.

[0088] Figure 4 Shown along Figure 2 A cross-sectional view of a turbomolecular pump is shown along the section line BB.

[0089] Figure 5 Shown along Figure 2 A cross-sectional view of the turbomolecular pump is shown along the section line CC, and

[0090] Figure 6 A possible embodiment of a vacuum pump according to the invention is shown as a component of a vacuum system according to the invention.

[0091] Reference numerals list

[0092] 111, 11 turbomolecular pump

[0093] 113, 13 inlet flange

[0094] 115 Pump inlet

[0095] 117 Pump outlet

[0096] 119, 19 shell

[0097] 121, 21 lower parts

[0098] 123,23 Electronic component housing

[0099] 125, 25 motor

[0100] 127, 27 accessory connector

[0101] 129, 29 data interface

[0102] 131 Power connector

[0103] 133 Overflow inlet

[0104] 135 shielding gas connector

[0105] 137 Motor Room

[0106] 139 Coolant connector

[0107] 141 bottom side

[0108] 143 screws

[0109] 145 bearing cap

[0110] 147 Fixed drilling

[0111] 148 Coolant Line

[0112] 149, 49 rotor

[0113] 151, 51 rotation axis

[0114] 153.53 rotor shaft

[0115] 155 rotor disc

[0116] 157 stator plate

[0117] 159 Spacer Ring

[0118] 161 rotor hub

[0119] 163 Holvik rotor sleeve

[0120] 165 Holvik rotor sleeve

[0121] 167 Holvik stator sleeve

[0122] 169 Holvik stator sleeve

[0123] 171 Holvik Gap

[0124] 173 Holvik Gap

[0125] 175 Holvik Gap

[0126] 179 connection channel

[0127] 181, 81 rolling bearings

[0128] 183, 83 permanent magnetic bearings

[0129] 185 injection nut

[0130] 187 plates

[0131] 189 plugins

[0132] 191, 91 rotor side half bearing

[0133] 193, 93 half bearing on the stator side

[0134] 195 Ring Magnet

[0135] 197 Ring Magnet

[0136] 199 bearing clearance

[0137] 201 bearing member section

[0138] 203 bearing member section

[0139] 205, 105 radial struts

[0140] 207 Covering element

[0141] 209 support ring

[0142] 211 fixed ring

[0143] 213 disc spring

[0144] 215 Emergency or safety bearing

[0145] 217 motor stator

[0146] 219 The Intermediate Space

[0147] 221 Wall

[0148] 223 labyrinth seal

[0149] 12 Vacuum system

[0150] 14 Inertial Measurement Unit

[0151] 16 Inertial Sensors

[0152] 18 Control Devices

[0153] 20 Storage device

[0154] 22 vacuum tube, circuit board

[0155] 24 System control device for vacuum system DETAILED DESCRIPTION

[0156] Figure 1 The turbomolecular pump 111 shown in the figure comprises a pump inlet 115, which is surrounded by an inlet flange 113, to which a vacuum chamber (not shown) can be connected in a manner known per se. Gas from the vacuum chamber can be drawn out of the vacuum chamber via the pump inlet 115 and moves through the pump to a pump outlet 117, to which a pre-vacuum pump, i.e., for example, an impeller-type rotary pump, can be connected.

[0157] In accordance with Figure 1 In the orientation of the vacuum pump of FIG. 1 , the inlet flange 113 forms the upper end of a housing 119 of the vacuum pump 111. The housing 119 comprises a lower part 121, to the side of which an electronics housing 123 is arranged. The electrical and / or electronic components of the vacuum pump 111 are accommodated in the electronics housing 123, for example, to operate a motor 125 (see also FIG. 1 ) arranged in the vacuum pump. Figure 3 ). A plurality of connectors 127 for accessories are provided on the electronics housing 123. In addition, a data interface 129 and a power supply connector 131, for example, according to the RS485 standard, are provided on the electronics housing 123.

[0158] There are also turbomolecular pumps which do not have an electronics housing attached in this way, but are connected to external drive electronics.

[0159] An overflow inlet 133, in particular in the form of an overflow valve, is provided on the housing 119 of the turbomolecular pump 111, via which the vacuum pump 111 can be overflowed. In addition, a protective gas connection 135, also referred to as a purge gas connection, is provided in the region of the lower part 121, via which purge gas can be introduced into the motor chamber 137 in order to protect the motor 125 (see, for example, Figure 3 ) is protected from the gas supplied to the pump, in which the motor 125 is installed in the vacuum pump 111. In addition, two coolant connections 139 are provided in the lower part 121, one of which is provided as an inlet and the other coolant connection as an outlet for a coolant, which can be introduced into the vacuum pump for cooling purposes. Other existing turbomolecular vacuum pumps (not shown) are operated only with air cooling.

[0160] The bottom side 141 of the vacuum pump can be used as a bearing surface, so that the vacuum pump 111 can be operated in a manner standing on the bottom side 141. However, the vacuum pump 111 can also be fixed to the vacuum chamber via the inlet flange 113 and thus remain suspended to a certain extent. In addition, the vacuum pump 111 can be designed so that it can be operated in a manner standing on the bottom side 141. Figure 1The vacuum pump can also be put into operation when oriented in different ways as shown. It is also possible to realize an embodiment of the vacuum pump in which the bottom side 141 is not arranged to be oriented downwards, but to be arranged to be oriented to the side or upwards. In principle, any angle is feasible.

[0161] In particular, other existing turbomolecular vacuum pumps (not shown) which are larger than the pump shown here may not be operated in an upright manner.

[0162] exist Figure 2 Various screws 143 are also provided at the bottom side 141 shown in the figure, by means of which the vacuum pump components, which are not further specified here, are fixed to each other. For example, a bearing cover 145 is fixed to the bottom side 141 .

[0163] On the bottom side 141 there is also provided a fastening bore 147 via which the pump 111 can be fastened to a support surface. This is not possible with other existing turbomolecular vacuum pumps (not shown) which are in particular larger than the pump shown here.

[0164] exist Figures 2 to 5 1 and 2 show a coolant line 148 in which the coolant introduced and discharged via the coolant connection 139 can circulate.

[0165] like Figures 3 to 5 As shown in the cross-sectional view of , the vacuum pump includes a plurality of process gas pump stages to transport process gas present at a pump inlet 115 to a pump outlet 117 .

[0166] A rotor 149 is arranged in the housing 119 and has a rotor shaft 153 which is rotatable about an axis of rotation 151 .

[0167] The turbomolecular pump 111 comprises a plurality of turbomolecular pump stages connected in series for pumping efficiency, the turbomolecular pump stage having a plurality of radial rotor disks 155 fixed on the rotor shaft 153 and stator disks 157 arranged between the rotor disks 155 and fixed in the housing 119. Here, the rotor disks 155 and the adjacent stator disks 157 each form a turbomolecular pump stage. The stator disks 157 are kept at a desired axial distance from each other by spacer rings 159.

[0168] The vacuum pump also comprises Holweck pump stages which are arranged alternately with one another in the radial direction and which are effectively connected in series with one another for pumping; there are other turbomolecular vacuum pumps (not shown) which do not have Holweck pump stages.

[0169] The rotor of the Holweg pump stage comprises a rotor hub 161 arranged on the rotor shaft 153 and two cylinder-shaped Holweg rotor sleeves 163, 165 fixed to the rotor hub 161 and carried by the rotor hub, which are oriented coaxially with the rotor axis 151 and are nested in one another in the radial direction. In addition, two cylinder-shaped Holweg stator sleeves 167, 169 are provided, which are also oriented coaxially with the rotation axis 151 and are nested in one another as viewed in the radial direction.

[0170] The pumping effective surface of the Holwek pump stage is formed by the side surfaces of the Holwek rotor sleeves 163, 165 and the Holwek stator sleeves 167, 169, that is, by the radial inner and / or outer surfaces. The radial inner surface of the outer Holwek stator sleeve 167 is opposite to the radial outer surface of the outer Holwek rotor sleeve 163 to form a radial Holwek gap 171, and the first Holwek pump stage following the turbomolecular pump is formed by means of the radial outer surface. The radial inner surface of the outer Hoff rotor sleeve 163 is opposite to the radial outer surface of the inner Hoff stator sleeve 169 to form a radial Hoff gap 173, and the second Hoffwick pumping stage is formed by means of the radial inner surface. The radial inner surface of the inner Hoff stator sleeve 169 is opposite to the radial outer surface of the inner Hoff rotor sleeve 165 to form a radial Hoff gap 175, and the third Hoffwick pumping stage is formed by means of the radial inner surface.

[0171] A radially extending channel can be provided at the lower end of the Holweg rotor sleeve 163, via which the radially located Holweg gap 171 is connected to the middle Holweg gap 173. In addition, a radially extending channel can be provided at the upper end of the inner Hoff stator sleeve 169, via which the middle Hoff gap 173 is connected to the radially inner Hoff gap 175. Thus, the nested Holweg pump stages are connected in series with each other. In addition, a connecting channel 179 to the outlet 117 can be arranged at the lower end of the radially inner Holweg rotor sleeve 165.

[0172] The aforementioned pumping-active surfaces of Holweg stator sleeves 167 , 169 each have a plurality of Holweg grooves extending helically about rotation axis 151 in the axial direction, while the opposite side surfaces of Holweg rotor sleeves 163 , 165 are smooth and pre-drive the gas into the Holweg grooves for operating vacuum pump 111 .

[0173] For the rotatable mounting of the rotor shaft 153 , a rolling bearing 181 is provided in the region of the pump outlet 117 , and a permanent magnetic bearing 183 is provided in the region of the pump inlet 115 .

[0174] In the region of the rolling bearing 181, a conical injection-molded nut 185 is provided, which has an outer diameter that increases toward the rolling bearing 181. The injection-molded nut 185 is in sliding contact with at least one ejector of the working medium reservoir. In other existing turbomolecular vacuum pumps (not shown), an injection-molded screw can be provided instead of an injection-molded screw. Since different embodiments are therefore possible, the term "injection-molded nozzle" can also be used in this context.

[0175] The operating medium reservoir comprises a plurality of suction cups 187 stacked one on top of the other and serving to impregnate the rolling bearing 181 with an operating medium, for example with a lubricant.

[0176] During operation of the vacuum pump 111, the working medium is transferred from the working medium reservoir via the ejector to the rotating injection nut 185 by capillary action and is transported along the injection nut 185 in the direction of the increasing outer diameter of the injection nut 185 due to the centrifugal force to the rolling bearing 181, where the working medium performs a lubricating effect, for example. The rolling bearing 181 and the working medium reservoir are enclosed in the vacuum pump by a pot-shaped insert 189 and a bearing cover 145.

[0177] The permanent magnet bearing 183 comprises a bearing half 191 on the rotor side and a bearing half 193 on the stator side, each of which comprises a ring stack consisting of a plurality of permanent magnet rings 195, 197 stacked on each other in the axial direction. The annular magnets 195, 197 are arranged opposite to each other to form a radial bearing gap 199, wherein the annular magnets 195 on the rotor side are arranged radially on the outside and the annular magnets 197 on the stator side are arranged radially on the inside. The magnetic field present in the bearing gap 199 causes a magnetic repulsion force between the annular magnets 195, 197, which causes a radial support of the rotor shaft 153. The annular magnet 195 on the rotor side is carried by a bearing section 201 of the rotor shaft 153, which radially surrounds the annular magnet 195 on the outside. The annular magnet 197 on the stator side is carried by a bearing section 203 on the stator side, which extends through the annular magnet 197 and is suspended at a radial strut 205 of the housing 119. The rotor-side annular magnet 195 is fixed parallel to the rotation axis 151 by a cover element 207 coupled to the support section 201. The stator-side annular magnet 197 is fixed in a direction parallel to the rotation axis 151 by a fixing ring 209 connected to the support section 203 and a fixing ring 211 connected to the support section 203. In addition, a leaf spring 213 can be arranged between the fixing ring 211 and the annular magnet 197.

[0178] An emergency or safety bearing 215 is arranged inside the magnetic bearing, which in normal operation of the vacuum pump 111 runs idle without contact and only engages with the rotor 149 in the case of excessive radial deflection relative to the stator, in order to form a radial stop for the rotor 149 in order to prevent structures on the rotor side from colliding with structures on the stator side. The safety bearing 215 is designed as an unlubricated rolling bearing and forms a radial gap with the rotor 149 and / or the stator, which causes the safety bearing to disengage in normal pump operation. The positive radial deflection of the safety bearing 215 is large enough that the safety bearing 215 does not engage in normal operation of the vacuum pump 215, and is small enough at the same time that structures on the rotor side are prevented from colliding with structures on the stator side in any case.

[0179] The vacuum pump 111 comprises an electric motor 125 for rotating a driving 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. The permanent magnet arrangement can be arranged on the radial shoe side or in an embedded manner on the section of the rotor shaft 153 extending through the motor stator 217. An intermediate space 219 is provided between the motor stator 217 and the section of the rotor 149 extending through the motor stator 217, the intermediate space comprising a radial motor gap, via which the motor stator 217 and the permanent magnet arrangement can be magnetically influenced to transmit a driving torque.

[0180] The motor stator 217 is fixed in a housing in a motor chamber 137 provided for the motor 125. A protective gas can reach the motor chamber 137 via the protective gas connection 135, wherein the protective gas can also be called a purge gas and is, for example, air or nitrogen. The motor 125 can be protected from the influence of process gas, for example, from the influence of the corrosive effect of the process gas, via the protective gas. The motor chamber 137 can also be evacuated via the pump outlet 117, i.e., the vacuum pressure caused by the pre-vacuum pump connected to the pump outlet 117 at least approximately prevails in the motor chamber 137.

[0181] Furthermore, a so-called labyrinth seal 223 known per se may be provided between the rotor hub 161 and a wall 221 delimiting the motor chamber 137 , in particular in order to achieve better sealing of the motor chamber 217 with respect to radially outer Holwek pump stages.

[0182] Figure 6 based on Figure 3 1 and a cross section through the turbopump according to the invention shows a turbomolecular vacuum pump according to the invention, which is also referred to in simplified form below as a turbomolecular pump or as a turbopump, the cross section through the turbopump according to the invention corresponding to Figure 3 cross section.

[0183] As in Figure 6 As shown in the embodiments of the present invention, the present invention can therefore be combined with Figures 1 to 5 Describe the turbomolecular pump used.

[0184] The turbopump 11 according to the invention therefore has a rotor 49 with a shaft 53 which, during operation, is set in rotation about an axis of rotation 51 by means of the electric motor 25 .

[0185] The rotor 49 is provided with a mixing support. Figure 6 On the lower middle part), a rolling bearing 81 is provided for the rotor 49. On the HV side ( Figure 6 In the upper middle part, the rotor 49 is supported by a permanent magnet bearing 83, which has a bearing half 91 on the rotor side and a bearing half 93 on the stator side.

[0186] The vacuum pump 11 has an outer housing 19 connected to the lower part 21. On the HV side, ie at the pump inlet, the housing 19 has a so-called star in the region of the inlet flange 13, which includes a plurality of radial struts 105 which converge in the center, ie on the rotor axis 51.

[0187] The electronics housing 23 is detachably attached to the outer sides of the housing 19 and the lower part 21. Furthermore, the electronics housing 23 contains control and drive electronics (not shown) for the vacuum pump 11, in particular for the electric motor 25, but also for possible further components (not shown) of the vacuum pump 11, namely, for example sensors etc.

[0188] The electronics housing 23 is connected via electrical plug contacts, wherein the pumping-side contacts are formed in the region of the lower part 21 of the vacuum pump 11 on a printed circuit board 22 serving as a vacuum bushing.

[0189] In the embodiment shown here, the vacuum pump 11 according to the invention is a component of a vacuum system 12, which is only schematically indicated by dashed lines. The vacuum system 12 can, for example, form a pumping station comprising a vacuum chamber to be evacuated by means of the vacuum pump 11 and a primary pump (not shown) assigned to the vacuum pump 11.

[0190] In principle, the vacuum system 12 can be constructed in any complexity and, for example, comprise one or more vacuum chambers and, in addition to the vacuum pump according to the invention, one or more further vacuum pumps, which may or may not be designed in the manner according to the invention. The vacuum system 12 can be designed to be mobile or semi-mobile.

[0191] The vacuum system 12 has a system control device 24 , via which all components and parts of the vacuum system 12 can be controlled and which enables the exchange of control signals and data.

[0192] The vacuum pump 11 according to the invention can be connected to the system control device 24, for example, via a data interface 29, which is formed on the electronic component housing 23 of the vacuum pump 11. Figure 6 As shown, an accessory port 27 is also provided on the electronic component housing 23 .

[0193] The vacuum pump 11 according to the invention constitutes one or more embodiments for carrying out the monitoring method according to the invention. The vacuum system 12 according to the invention likewise constitutes one or more embodiments for carrying out the monitoring method according to the invention.

[0194] According to the invention, the vacuum pump 11 is provided with an inertial measurement unit 14, which is fixedly attached to a component of the pump 11. To illustrate that within the scope of the invention the inertial measurement unit 14 can be arranged at different locations of the vacuum pump 11, Figure 6 Two different attachment positions are shown purely by way of example.

[0195] According to a possible design of the present invention, the inertial measurement unit 14 is arranged at the pump inlet on the star-shaped piece mentioned above, which includes a plurality of radial struts 105, more precisely, centrally relative to the rotation axis 51. Alternatively, it can also be proposed to arrange the inertial measurement unit 14 eccentrically on the star-shaped piece of the vacuum pump 11.

[0196] According to a further exemplary embodiment of the invention, inertial measurement unit 14 is attached to the aforementioned printed circuit board 22 which forms a vacuum sleeve on lower part 21 of pump 11 .

[0197] In principle, it is possible according to the invention to provide more than one inertial measurement unit 14 on vacuum pump 11 .

[0198] like Figure 6 As shown in the enlarged schematic diagram at the top left, the inertial measurement unit 14 includes a plurality (six in this example) of inertial sensors 16. In a preferred embodiment, as already mentioned in the previous section as an example, three acceleration sensors and three rotational speed sensors are provided in order to cover all six possible degrees of freedom of the movement of the vacuum pump 11 in this way.

[0199] In order to avoid repetition, reference is made to the introduction with regard to possible applications of the vacuum pump 11 according to the invention and the vacuum system 12 according to the invention, wherein the monitoring method can be used with the aid of the above-described Figure 6The described vacuum pump 11 according to the invention and the described vacuum system 12 are implemented.

[0200] The invention thus creates a simple, reliable and inexpensive possibility for monitoring the state of a vacuum pump and a vacuum system based on the measurement data of an inertial measurement unit assigned to the vacuum pump.

Claims

1. A method for monitoring a vacuum pump (11), the vacuum pump (11) having an inertial measurement unit (14) assigned to the vacuum pump (11), the inertial measurement unit (14) comprising an inertial sensor (16), the inertial sensor (16) comprising: a first inertial sensor and / or a second inertial sensor, the first inertial sensor being designed to acquire a translational movement of the vacuum pump (11) and to provide first measurement data related to the translational movement of the vacuum pump (11), the second inertial sensor being designed to acquire an orientation of the vacuum pump (11) and to provide second measurement data related to the orientation of the vacuum pump (11), wherein, before, during and / or after the operation of the vacuum pump (11), the translational movement of the vacuum pump (11) and / or the orientation of the vacuum pump (11) are detected by means of the inertial measurement unit (14) of the vacuum pump (11), wherein a control device (18) connected to the inertial measurement unit (14) obtains information by evaluating the first measurement data and the second measurement data, The vacuum pump (11) comprises a rotor (49) which is rotated by means of a drive motor (25) during operation, and one or more state information of the vacuum pump (11) is determined based on the first measurement data and / or the second measurement data, and an imbalance of the rotor (49) and / or a vibration state of the vacuum pump (11) are determined as the state information of the vacuum pump (11), wherein the rotor imbalance and / or the vibration state are repeatedly determined during operation of the vacuum pump (11), and - calculating at least one measure of the time variation of the rotor imbalance and / or of the vibration state, - in the case of approaching relative or absolute limit values ​​of the rotor imbalance and / or the vibration state, or in the case of approaching relative or absolute limit values ​​of the temporal variation of the rotor imbalance and / or the vibration state, calculating an estimate of the next maintenance date of the vacuum pump (11), or adjusting a currently preset maintenance interval, - calculating a measure of the utilization reserve of the vacuum pump (11), and / or - Calculate and output a recommended value for the time until the next maintenance of the vacuum pump (11).

2. The method according to claim 1, wherein: The first measurement data and the second measurement data are raw measurement data and / or pre-processed measurement data.

3. The method according to claim 1, wherein: The at least one measure for calculating the time variation of the rotor imbalance and / or the vibration state is calculated with reference to a corresponding basic state of the rotor imbalance and / or the vibration state determined at a constant operating speed of the rotor (49).

4. The method according to claim 1, wherein: Taking into account the usage profile of the vacuum pump (11) to date, a recommended value for the time until the next maintenance of the vacuum pump (11) is calculated and output.

5. The method according to claim 1, wherein: At least one measure of the temporal variation is the rate of change.

6. The method according to claim 1, wherein: The one or more pieces of status information are output via an output device (27, 29) of the vacuum pump (11) and / or are stored in a storage device (20) of the vacuum pump (11).

7. The method according to claim 1 or 6, wherein: The orientation of the vacuum pump (11) in space is determined as status information of the vacuum pump (11).

8. The method according to claim 7, in, The control device (18) of the vacuum pump (11) is designed to allow or prohibit the start of operation of the vacuum pump (11) according to the determined orientation of the vacuum pump (11), and / or wherein the determined orientation of the vacuum pump (11) is taken into account when evaluating a vibration-related frequency spectrum of the vacuum pump (11), and / or The orientation of the vacuum pump (11) is stored only when at least one of the following special, pre-set events occurs: When the vacuum pump (11) is powered on, At the start of operation of the vacuum pump (11), and When changing the installation position of the vacuum pump (11), is stored.

9. The method according to claim 1, wherein: In the event of exceeding a relative or absolute limit value of the rotor imbalance and / or of the vibration state, or in the event of exceeding a relative or absolute limit value of the temporal variation of the rotor imbalance and / or of the vibration state, a reaction is triggered.

10. The method according to claim 9, wherein: The triggering reaction is the output of a warning.

11. The method according to claim 1, wherein: Determining the vibration state of the vacuum pump (11) as state information of the vacuum pump (11) comprises: determining a frequency spectrum related to the vibration of the vacuum pump (11).

12. The method according to claim 1, in, The vibration state is determined during acceleration of the vacuum pump (11) in which the rotational speed of the rotor (49) of the vacuum pump (11) increases, and / or during deceleration or coasting of the vacuum pump (11) in which the rotational speed of the rotor (49) of the vacuum pump (11) decreases, and / or, wherein if, based on the vibration state determined, the control device (18) of the vacuum pump (11) detects one or more other vacuum pumps that are operated at at least approximately the same operating speed as the vacuum pump (11), the rotational speed of the rotor (49) is automatically changed in order to prevent a flutter state, And / or, wherein, based on the determined vibration state, one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) are monitored.

13. The method according to claim 12, wherein: The vibration state is determined even after the acceleration, when the rotor is running at the operating speed.

14. The method according to claim 12, wherein: The vibration state is determined and stored.

15. The method according to claim 12, wherein: When the vibration state is determined, the resonance state of the vacuum pump (11) is determined.

16. The method according to claim 15, wherein: The information related to the resonance state is provided to be output to an external device, or the information related to the resonance state is provided to be called by an external device.

17. The method according to claim 16, wherein: A warning indication is outputted by the vacuum pump (11), or the rotation speed of the rotor (49) is automatically adjusted to prevent the vacuum pump (11) from operating in a resonance state.

18. The method according to claim 12, wherein: Monitoring one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) based on the determined vibration state includes: monitoring the time performance of the one or more preset parameters and / or signals of the one or more inertial sensors (16).

19. The method according to claim 12, wherein: The step of monitoring one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) according to the determined vibration state comprises: Reference is made to a target state of the vacuum pump (11) determined in an automatic learning phase, wherein after the learning phase, a control device (18) of the vacuum pump (11) checks whether one or more of the monitored parameters and / or one or more monitored signals correspond to the target state, and when a deviation from the target state is identified in the check, a change in the relevant parameter or signal is evaluated and / or assessed.

20. The method according to claim 19, wherein: The evaluating and / or assessing of the change of the relevant parameter or signal includes evaluating and / or assessing with respect to a predefined criterion.

21. The method according to claim 1, wherein: One or more specific events are determined as status information of the vacuum pump (11).

22. The method according to claim 21, wherein the one or more special events are output via an output device (27, 29) of the vacuum pump (11) and / or are stored in a storage device (20) of the vacuum pump (11).

23. The method according to claim 21, in, The vacuum pump (11) comprises a rotor (49) which is rotated by means of a drive motor (25) during operation, and an axial displacement of the rotor (49) between a first axial position and a second axial position is detected as a special event during operation of the vacuum pump (11), and / or Therein, the movement of the vacuum pump (11) as a whole is detected as a special event.

24. The method according to claim 23, wherein: The first axial position is a pre-vacuum position.

25. The method according to claim 23, wherein: The second axial position is a high vacuum position.

26. The method of claim 23, wherein: The movement of the vacuum pump (11) as a whole is detected as a special event and the movement is analyzed with respect to the direction and value of the translation and / or rotation of the vacuum pump.

27. The method according to claim 1, in, The first measured data and the second measured data and / or the information obtained by evaluating the first measured data and the second measured data can be output or called up only if authorization is present.

28. The method according to claim 27, wherein: The first measured data and the second measured data and / or information obtained by evaluating the first measured data and the second measured data are output and / or retrieved via an interface (29) or an accessory connection (27) of the vacuum pump (11).

29. A method for monitoring a vacuum system (12), the vacuum system (12) comprising at least one vacuum pump (11) and at least one vacuum chamber, the vacuum pump (11) having an inertial measurement unit (14) assigned to the vacuum pump (11), the inertial measurement unit comprising an inertial sensor (16), the inertial sensor (16) comprising at least: a first inertial sensor and a second inertial sensor, wherein the first inertial sensor is configured to acquire a translational movement of the vacuum pump (11) and to provide first measurement data related to the translational movement of the vacuum pump (11), and the second inertial sensor is configured to acquire an orientation of the vacuum pump (11) and to provide second measurement data related to the orientation of the vacuum pump (11), wherein, before, during and / or after the operation of the vacuum system (12), the translational movement and / or orientation of the vacuum pump (11) of the vacuum system (12) is detected by means of the inertial measurement unit (14) of the vacuum pump (11), wherein a control device (18) connected to the inertial measurement unit (14) obtains information by evaluating the first measurement data and the second measurement data, The vacuum pump (11) comprises a rotor (49) which is rotated by means of a drive motor (25) during operation, and one or more state information of the vacuum pump (11) is determined based on the first measurement data and / or the second measurement data, and the imbalance of the rotor (49) and / or the vibration state of the vacuum system (12) are determined as the state information of the vacuum system (12). wherein the rotor imbalance and / or the vibration state are repeatedly determined during operation of the vacuum pump (11), and - calculating at least one measure of the time variation of the rotor imbalance and / or of the vibration state, - in the case of approaching relative or absolute limit values ​​of the rotor imbalance and / or the vibration state, or in the case of approaching relative or absolute limit values ​​of the temporal variation of the rotor imbalance and / or the vibration state, calculating an estimate of the next maintenance date of the vacuum pump (11), or adjusting a currently preset maintenance interval, - calculating a measure of the utilization reserve of the vacuum pump (11), and / or - Calculate and output a recommended value for the time until the next maintenance of the vacuum pump (11).

30. The method of claim 29, wherein: The first measurement data and the second measurement data are raw measurement data and / or pre-processed measurement data.

31. The method of claim 29, wherein: The at least one measure for calculating the time variation of the rotor imbalance and / or the vibration state is calculated with reference to a corresponding basic state of the rotor imbalance and / or the vibration state determined at a constant operating speed of the rotor (49).

32. The method of claim 29, wherein: Taking into account the usage profile of the vacuum pump (11) to date, a recommended value for the time until the next maintenance of the vacuum pump (11) is calculated and output.

33. The method of claim 29, wherein: At least one measure of the temporal variation is the rate of change.

34. The method of claim 29, wherein: The one or more pieces of status information are output via an output device (27, 29) of the vacuum pump (11) and / or are stored in a storage device (20) of the vacuum pump (11).

35. The method according to claim 29 or 34, in, An orientation of the vacuum pump (11) relative to one or more other components of the vacuum system (12) is determined as status information of the vacuum system (12).

36. The method according to claim 35, in, The control device (18) of the vacuum pump (11) is designed to allow or prohibit the start of operation of the vacuum pump (11) according to the determined orientation of the vacuum pump (11), and / or wherein the determined orientation of the vacuum pump (11) is taken into account when evaluating the vibration-related frequency spectrum of the vacuum system (12), and / or The orientation of the vacuum pump (11) is stored only when at least one of the following special, pre-set events occurs: When the vacuum pump (11) is powered on, When the vacuum pump (11) starts to operate, At the start of operation of the predetermined components of the vacuum system (12) including the vacuum pump (11), except for the vacuum pump (11), and When changing the installation position of the vacuum pump (11), is stored.

37. The method according to claim 29, in, In the event of exceeding a relative or absolute limit value of the rotor imbalance and / or of the vibration state, or in the event of exceeding a relative or absolute limit value of the temporal variation of the rotor imbalance and / or of the vibration state, a reaction is triggered.

38. The method of claim 37, wherein: The triggering reaction is the output of a warning.

39. The method of claim 29, wherein: Determining the vibration state of the vacuum system (12) as state information of the vacuum system (12) comprises: determining a frequency spectrum of vibrations related to the vacuum system (12).

40. The method of claim 29, wherein: The vibration state is determined during acceleration of the vacuum pump (11) in which the rotational speed of the rotor (49) of the vacuum pump (11) increases, and / or during deceleration or inertial motion of the vacuum pump (11) in which the rotational speed of the rotor (49) of the vacuum pump (11) decreases, and / or, if, based on the determined vibration state, one or more other vacuum pumps operating at at least approximately the same operating speed as the vacuum pump (11) are identified by the system control device (24) of the vacuum system (12), the rotational speed of the rotor (49) is automatically changed in order to prevent a flutter state, and / or, based on the determined vibration state, one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) are monitored.

41. The method of claim 40, wherein: The vibration state is determined even after the acceleration, when the rotor is running at the operating speed.

42. The method of claim 40, wherein: The vibration state is determined and stored.

43. The method of claim 40, wherein: When the vibration state is determined, the resonance state of the vacuum system (12) is determined.

44. The method of claim 43, wherein: The information related to the resonance state is provided to be output to an external device, or the information related to the resonance state is provided to be called by an external device.

45. The method of claim 44, wherein: The external device is the system control device (24) of the vacuum system (12).

46. ​​The method of claim 44, wherein: A warning indication is outputted by the vacuum system (12), or the rotation speed of the rotor (49) is automatically adjusted to prevent the vacuum pump (11) from operating in a resonance state.

47. The method of claim 40, wherein: Monitoring one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) based on the determined vibration state includes: monitoring the time performance of the one or more preset parameters and / or signals of the one or more inertial sensors (16).

48. The method of claim 40, wherein: The step of monitoring one or more preset parameters of the vacuum pump (11) and / or signals of one or more inertial sensors (16) of the vacuum pump (11) according to the determined vibration state comprises: Reference is made to a target state of the vacuum system (12) determined in an automatic learning phase, wherein after the learning phase, a control device (18) of the vacuum pump (11) checks whether one or more of the monitored parameters and / or the monitored signals of one or more of the inertial sensors (16) correspond to the target state, and when a deviation from the target state is identified in the check, a change in the relevant parameter or signal is evaluated and / or assessed.

49. The method of claim 48, wherein: The evaluating and / or assessing of the change of the relevant parameter or signal includes evaluating and / or assessing with respect to a predefined criterion.

50. The method of claim 29, wherein: One or more specific events are determined as status information of the vacuum system (12).

51. The method according to claim 50, wherein the one or more special events are output via an output device (27, 29) of the vacuum pump (11) and / or are stored in a storage device (20) of the vacuum pump (11).

52. The method according to claim 50, in, The vacuum pump (11) comprises a rotor (49) which is rotated by means of a drive motor (25) during operation, and an axial displacement of the rotor (49) between a first axial position and a second axial position is detected as a special event during operation of the vacuum pump (11), and / or Therein, the movement of the vacuum pump (11) as a whole is detected as a special event.

53. The method of claim 52, wherein: The first axial position is a pre-vacuum position.

54. The method of claim 52, wherein: The second axial position is a high vacuum position.

55. The method of claim 52, wherein: The movement of the vacuum pump (11) as a whole is detected as a special event and the movement is analyzed with respect to the direction and value of the translation and / or rotation of the vacuum pump.

56. The method according to claim 29, in, The first measurement data and the second measurement data, and / or information obtained by evaluating the first measurement data and the second measurement data, can only be output or called up if authorization is present, and / or The first measurement data and the second measurement data, and / or information obtained by evaluating the first measurement data and the second measurement data, are output to a system control device (24) of a vacuum system (12) including the vacuum pump (11) and / or are called by the system control device (24).

57. The method of claim 56, wherein: The first measurement data and the second measurement data, and / or information obtained by evaluating the first measurement data and the second measurement data, are output and / or retrieved via an interface (29) or an accessory connection (27) of the vacuum pump (11).

58. The method of claim 56, wherein: Via an interface (29) or an accessory connector (27) of the vacuum pump (11), the first measurement data and the second measurement data and / or information obtained by evaluating the first measurement data and the second measurement data are output to a system control device (24) of a vacuum system (12) including the vacuum pump (11) and / or are called by the system control device (24).

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