JP2023127381A - Controller of vacuum pump and control method - Google Patents

Abstract

To prevent an operation mode from wrongly transferring to an operation restriction mode.SOLUTION: A controller 6 comprises a control unit 62. The control unit 62 counts the number of times each of a plurality of types of abnormalities has occurred in a vacuum pump 1, and generates a serious alarm when the number of times each of the plurality of types of abnormalities has occurred exceeds a predetermined threshold.SELECTED DRAWING: Figure 3

Description

The present invention relates to a vacuum pump control device and a vacuum pump control method.

Some vacuum pumps exhaust gas by rotating a rotor with a motor. In the vacuum pump described in Patent Document 1, the axial displacement of the rotor shaft is detected, the number of detections is integrated, and if the integrated number exceeds a predetermined number, or if the integrated number exceeds a predetermined number within a predetermined time. It is stated that a warning will be issued.

Japanese Patent Application Publication No. 2004-150340

According to the vacuum pump described in Patent Document 1, an alarm is issued based only on the cumulative number of times the axial displacement of the rotor shaft is detected, and other types of abnormalities are not taken into account. Therefore, for example, if the cumulative number of detected axial displacements of the rotor shaft exceeds a predetermined number, but the number of occurrences of other types of abnormalities is small, even though the possibility of the vacuum pump failing is low. , an alarm will be issued. In other words, with conventional pumps, there is a risk that an alarm may be generated even when there is no need to generate an alarm. Although not particularly limited, for example, in a configuration in which the vacuum pump is stopped at the same time as an alarm, the vacuum pump will be stopped even though there is a low possibility that the vacuum pump will malfunction, and the vacuum pump will be used to exhaust the air. There is a risk of interfering with the operation of the target device. Further, when such a vacuum pump is applied to semiconductor manufacturing equipment, unnecessary stoppage of the vacuum pump leads to a serious problem such as a stoppage of the production line.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to prevent a serious alarm from being erroneously generated due to the number of occurrences of only one type of abnormality.

A control device according to one aspect of the present invention is a control device for a vacuum pump that drives a rotor to rotate with a motor to exhaust gas. The control device includes a control section. The control unit counts the number of times each of the plurality of types of abnormalities occurs in the vacuum pump, and generates a serious alarm when the number of times each of the plurality of types of abnormalities occurs exceeds a predetermined threshold.

In the above-mentioned control device, a serious alarm is generated when the number of occurrences of abnormalities in each of the plurality of types of vacuum pumps exceeds a predetermined threshold value. In other words, whether or not to generate a serious alarm is determined based on the number of occurrences of each of the plurality of types of abnormalities. This makes it possible to prevent a serious alarm from being erroneously generated when the number of occurrences of only one type of abnormality is large and the number of occurrences of other abnormalities is small and the possibility of failure of the vacuum pump is low. Note that the occurrence of a serious alarm does not necessarily require notification to the user (by display, sound, etc.), and may simply be stored in the storage unit.

FIG. 3 is a diagram showing the configuration of a vacuum pump. FIG. 3 is a diagram showing the configuration of a control device. It is a flowchart showing the operation of the vacuum pump. 3 is a flowchart showing the startup operation of the vacuum pump 1. FIG.

<Overall configuration of vacuum pump>
A vacuum pump 1 will be explained using FIG. 1. FIG. 1 is a diagram showing the configuration of a vacuum pump 1. As shown in FIG. The vacuum pump 1 includes a housing 2, a base 3, a rotor 4, a stator 5, and a control device 6.

The housing 2 includes a first end 11, a second end 12, and a first internal space SP1. An intake port 13 is provided at the first end 11 . The first end 11 is attached to an exhaust target (not shown). The first internal space SP1 communicates with the intake port 13. The second end 12 is located opposite to the first end 11 in the extending direction of the axis A1 of the rotor 4. The second end 12 is connected to the base 3. The base 3 includes a base end 14 . The base end 14 is connected to the second end 12 of the housing 2.

The rotor 4 is connected to a shaft 21. The shaft 21 extends in the direction of extension of the axis A1. The shaft 21 is rotatably housed in the base 3. The rotor 4 includes multiple stages of rotor blades 22 and a rotor cylindrical portion 23. The multiple stages of rotor blades 22 are each connected to the shaft 21. The plurality of rotor blades 22 are arranged at intervals from each other in the direction of extension of the axis A1. Although not shown, the multiple stages of rotor blades 22 each extend radially around the shaft 21 . In the drawings, only one of the multiple stages of rotor blades 22 is given a reference numeral, and the reference numerals of the other rotor blades 22 are omitted. The rotor cylindrical portion 23 is arranged below the multiple stages of rotor blades 22 . The rotor cylindrical portion 23 extends in the direction of extension of the axis A1.

The stator 5 includes multiple stages of stator blades 31 and a stator cylindrical portion 32. The stator blades 31 in multiple stages are connected to the inner surface of the housing 2 . The stator blades 31 in multiple stages are arranged at intervals from each other in the extending direction of the axis A1. The plurality of stages of stator blades 31 are arranged between the plurality of stages of rotor blades 22, respectively. Although not shown, the stator blades 31 in multiple stages each extend radially around the shaft 21 . In the drawings, only two of the stator blades 31 in multiple stages are labeled, and the symbols of the other stator blades 31 are omitted. The stator cylindrical portion 32 is fixed to the base 3 in a thermally contacting state. The stator cylindrical portion 32 is disposed facing the rotor cylindrical portion 23 with a slight gap in the radial direction of the rotor cylindrical portion 23. A spiral groove is provided on the inner peripheral surface of the stator cylindrical portion 32.

As shown in FIG. 1, a second internal space SP2 is formed further downstream of the end portions of the rotor cylindrical portion 23 and the stator cylindrical portion 32 on the exhaust downstream side. Gas exhausted from the attachment target is exhausted into the second internal space SP2. The second internal space SP2 communicates with the exhaust port 16. The exhaust port 16 is provided in the base 3. Another vacuum pump (not shown) is connected to the exhaust port 16.

The control device 6 is housed inside a casing 33 provided at the bottom of the base 3, and controls the vacuum pump 1. The control device 6 also controls the floating position of the shaft 21 measured by displacement sensors 44A to 44C, which will be described later, the current value supplied to the motor 42 measured by a current value measuring device, and the current value measured by a rotation speed sensor 43. When the rotation speed of the rotor 4 is not within a normal value range, an alarm or warning is generated to notify that an abnormality has occurred in the vacuum pump 1. The control device 6 is a computer system including a CPU, a storage device such as a ROM, various interfaces, and the like.

An operating device 7 is connected to the control device 6 . The operating device 7 is a device for inputting various information regarding the control of the vacuum pump 1. Further, the operating device 7 may include a display for displaying various information regarding the vacuum pump 1. The operating device 7 is, for example, an operating panel including an input device and a display. The input device is, for example, a device including a keyboard, buttons, etc., and/or a device such as a touch panel that allows input of various information through user operations. In addition, the operating device 7 may be a terminal such as a personal computer, a tablet terminal, or a mobile terminal.

The vacuum pump 1 includes a plurality of bearings 41A to 41E, a motor 42, and a rotation speed sensor 43. The plurality of bearings 41A to 41E are attached to the base 3 at a position where the shaft 21 is accommodated. The plurality of bearings 41A to 41E rotatably support the rotor 4. The bearings 41A and 41E are, for example, ball bearings. On the other hand, the other bearings 41B to 41D are magnetic bearings. The bearings 41B to 41D, which are magnetic bearings, each include a bearing electromagnet and displacement sensors 44A to 44C (FIG. 2), and the floating position of the shaft 21 and the like are detected by the displacement sensors 44A to 44C.

The motor 42 rotates the rotor 4 . Motor 42 includes a motor rotor 42A and a motor stator 42B. Motor rotor 42A is attached to shaft 21. Motor stator 42B is attached to base 3. Motor stator 42B is arranged facing motor rotor 42A. A motor current measuring device 45 (FIG. 2) that measures the current value supplied to the motor 42 is connected to the motor 42. The rotation speed sensor 43 measures the rotation speed of the shaft 21 (ie, the rotor 4).

The outer wall of the base 3 is provided with a heater 51 and a cooling water pipe (not shown) for controlling the temperature of the base 3. The temperature of the base 3 is detected by a temperature sensor 52. Based on the temperature detected by the temperature sensor 52, the temperature of the base 3 is controlled by balancing the heating of the base 3 by the heater 51 and the cooling by the cooling water flowing through the cooling water pipe. Further, a heater current measuring device 53 (FIG. 2) that measures the current supplied to the heater 51 is connected to the heater 51.

In the vacuum pump 1, the multiple stages of rotor blades 22 and the multiple stages of stator blades 31 constitute a turbo molecular pump section. Further, the rotor cylindrical portion 23 and the stator cylindrical portion 32 constitute a thread groove pump portion. In the vacuum pump 1, as the rotor 4 is rotated by the motor 42, gas flows into the first internal space SP1 from the intake port 13. The gas in the first internal space SP1 passes through the turbo molecular pump section and the thread groove pump section, and is exhausted to the second internal space SP2. The gas in the second internal space SP2 is exhausted from the exhaust port 16. As a result, the inside of the attachment target attached to the intake port 13 becomes in a high vacuum state.

<Configuration of control device>
The configuration of the control device 6 will be explained using FIG. 2. FIG. 2 is a diagram showing the configuration of the control device 6. As shown in FIG. The control device 6 includes a storage section 61 and a control section 62. The storage unit 61 is part or all of a storage area provided in a storage device that constitutes the control device 6 . The storage unit 61 stores various parameters related to the vacuum pump 1, programs for controlling the vacuum pump 1, and the like. Specifically, the storage unit 61 stores an abnormality occurrence condition CON, a serious alarm condition RCO, a serious alarm occurrence history AH, and a cancellation password PW. The abnormality occurrence condition CON defines the conditions for determining that an abnormality has occurred in the vacuum pump 1.

Specifically, the abnormality occurrence condition CON is that an abnormality in the rotation speed of the rotor 4 has occurred when the rotation speed of the rotor 4 measured by the rotation speed sensor 43 becomes a predetermined rotation speed or less. Establish. This abnormality in the rotation speed is an abnormality related to the load on the vacuum pump 1, and indicates that the vacuum pump 1 is in an overload state. The term "overload state" refers to a state in which the torque of the motor 42 required to rotate the rotor 4 to a predetermined number of rotations is greater than normal. The fact that the vacuum pump 1 is overloaded indicates, for example, that a large amount of product has accumulated inside the vacuum pump 1. If this state continues for a long period of time, there is a possibility that the deposited products will come into contact with the rotor blades 22 of the vacuum pump 1 and cause a failure in which the rotor blades 22 are damaged.

The abnormality occurrence condition CON is when the position of the shaft 21 measured by the displacement sensors 44A to 44C fluctuates by a predetermined fluctuation range or more, or the position of the shaft 21 deviates from the axis A1 within a predetermined range. In some cases, it is determined that an abnormality has occurred in the position of the shaft 21 (rotor 4). The abnormality in the position of the shaft 21 is an abnormality related to the vibration of the vacuum pump 1, and means that the vacuum pump 1 is in a vibrating state. When vibrations occur in the vacuum pump 1, for example, the rotor blades 22 of the vacuum pump 1 may come into contact with other parts (for example, the stator blades 31). As a result, if vibration occurs in the vacuum pump 1, the rotor blades 22 (and stator blades 31) may be damaged. Furthermore, the fact that the vacuum pump 1 is vibrating may indicate, for example, that a large amount of products is deposited on the rotor 4 of the vacuum pump 1. this is. This is caused by the rotor 4 becoming unbalanced due to the accumulation of products.

The abnormality occurrence condition CON determines that an abnormality has occurred in the current value of the motor 42 when the current value of the motor 42 measured by the motor current measuring device 45 exceeds a predetermined value. This abnormality in the current of the motor 42 indicates that the motor 42 is operating with excessive torque generated. That is, the abnormality in the current of the motor 42 is an abnormality related to the load on the vacuum pump 1, and indicates that the vacuum pump 1 is in an overload state. The fact that the vacuum pump 1 is overloaded indicates, for example, that a large amount of product has accumulated inside the vacuum pump 1.

The abnormality occurrence condition CON is that the temperature of the base 3 measured by the temperature sensor 52 is below a predetermined temperature, and/or the current value of the heater 51 measured by the heater current measuring device 53 is below a predetermined value. When , it is determined that an abnormality related to the temperature of the vacuum pump 1 has occurred. An abnormality regarding the temperature of the vacuum pump 1 indicates that the temperature of the vacuum pump 1 is not properly controlled. If the temperature of the vacuum pump 1 is not properly controlled, products may accumulate inside the vacuum pump 1, and this product may come into contact with the rotor blades 22, causing damage to the rotor blades 22. Abnormalities related to temperature are often caused by, for example, a disconnection of the heater 51 or a failure of the temperature sensor 52. Furthermore, when the temperature of the vacuum pump 1 reaches a predetermined value or higher, a thermal switch (not shown) stops power supply to the heater 51.

The abnormality occurrence counter CNT is information representing the number of times the above abnormality has occurred. Specifically, the abnormality occurrence counter CNT represents the number of occurrences of each of the plurality of types of abnormalities (load-related abnormalities, temperature-related abnormalities, and vibration-related abnormalities).

The critical alarm condition RCO defines a condition for generating an alarm (referred to as a critical alarm) for shifting the operation mode of the vacuum pump 1 to the limited operation mode. The operation restriction mode is an operation mode in which the operation of the vacuum pump is restricted more than normal when the vacuum pump 1 is restarted after the vacuum pump has stopped once due to the occurrence of a serious alarm. The serious alarm condition RCO stores how many times each of the above-mentioned plurality of abnormalities occurs to generate a serious alarm. Specifically, the serious alarm condition RCO is set, for example, when a vibration-related abnormality occurs at a first threshold or more, a load-related abnormality occurs at a second threshold or more, and a temperature-related abnormality occurs at a third threshold or more. It is specified that a serious alarm shall be generated.

Using the operating device 7, the user can arbitrarily change the first to third thresholds included in the serious alarm condition RCO. In addition, the user can use the operating device 7 to select two or more types of abnormalities to be included in the serious alarm condition RCO from among multiple types (three types) of abnormalities (load-related abnormalities, temperature-related abnormalities, and vibration-related abnormalities). can be selected. Thereby, the conditions for generating a serious alarm can be optimally set according to the environment in which the vacuum pump 1 is used.

The serious alarm occurrence history AH is information indicating whether or not a serious alarm has occurred. The serious alarm occurrence history AH can be, for example, flag information that has a value of "1" when a serious alarm has occurred, and has a value of "0" when no serious alarm has occurred. The release password PW is a password for releasing the serious alarm that has occurred.

The control unit 62 is a hardware part configured by a CPU and various interfaces that configure the control device 6, and executes control of the vacuum pump 1. The control unit 62 realizes functions related to controlling the vacuum pump 1 by executing a program stored in the storage unit 61. Furthermore, some of the functions may be realized by hardware included in the control unit 62.

<Vacuum pump operation>
Hereinafter, the operation of the vacuum pump 1 will be explained using FIG. 3. FIG. 3 is a flowchart showing the operation of the vacuum pump 1. The operation of the vacuum pump 1 shown in FIG. 3 is the operation when no serious alarm has occurred before the vacuum pump 1 is started and the operation mode of the vacuum pump 1 is not the operation restriction mode. This operation is executed by the control device 6 of the vacuum pump 1.

When the vacuum pump 1 is activated and starts operating, the control unit 62 controls the rotation speed of the rotor 4 measured by the rotation speed sensor 43 and the rotation speed of the rotor 4 measured by the displacement sensors 44A to 44C while the vacuum pump 1 is in operation. the position of the shaft 21 measured by the motor current measuring device 45, the temperature of the base 3 measured by the temperature sensor 52, and the temperature of the heater 51 measured by the heater current measuring device 53. The current values are respectively acquired (step S1).

Next, the control unit 62 uses the rotation speed of the rotor 4, the position of the shaft 21, the current value of the motor 42, the temperature of the base 3, and the current value of the heater 51 obtained in step S1, and the abnormality occurrence condition CON. It is determined whether the conditions for the occurrence of an abnormality are met. For example, the control unit 62 compares these measured values with each threshold value indicated in the abnormality occurrence condition CON (step S2).

As a result of the above comparison, if the measured value of any of the above sensors corresponds to the abnormality occurrence condition indicated in the abnormality occurrence condition CON, for example, if the measured value of any of the sensors exceeds the threshold ( (“Yes” in step S2), the control unit 62 selects the items (rotational speed of the rotor 4, vibration of the shaft 21, current value of the motor 42, temperature of the base 3, It is determined that a type of abnormality (an abnormality related to vibration of the vacuum pump 1, an abnormality related to the rotational speed of the rotor 4, an abnormality related to the temperature of the vacuum pump 1) corresponding to the current value of the heater 51 has occurred (step S3). Note that when determining that an abnormality has occurred, the control unit 62 may notify the occurrence of an abnormality by, for example, emitting a sound or displaying an indication that an abnormality has occurred on the display of the operating device 7. good.

On the other hand, as a result of the above comparison, if the measured value of any of the above sensors does not correspond to the abnormality occurrence condition indicated in the abnormality occurrence condition CON (“No” in step S2), the operation of the vacuum pump 1 is as follows. Return to step S1. That is, the control unit 62 determines that no abnormality has occurred in the vacuum pump 1, and continues the operation of the vacuum pump 1.

If it is determined in step S3 that an abnormality has occurred, the control unit 62 increases the number of occurrences of the type of abnormality determined to have occurred in step S3 by 1 in the abnormality occurrence counter CNT (step S4).

After that, the control unit 62 compares the abnormality occurrence counter CNT and the serious alarm condition RCO, and the number of occurrences of each of the plurality of abnormalities indicated in the abnormality occurrence counter CNT is determined to be the serious alarm indicated in the serious alarm condition RCO. It is determined whether or not the occurrence condition is met (step S5). Specifically, for example, in the abnormality occurrence counter CNT, the number of occurrences of vibration-related abnormalities is greater than or equal to a first threshold, the number of occurrences of load-related abnormalities is greater than or equal to a second threshold, and the number of occurrences of temperature-related abnormalities is greater than or equal to a first threshold. When the number of occurrences is equal to or greater than the third threshold, the control unit 62 determines that the number of occurrences of each of the plurality of types of abnormalities corresponds to the serious alarm generation condition indicated in the serious alarm condition RCO.

If the number of occurrences of each of the plurality of types of abnormalities corresponds to the serious alarm generation condition (“Yes” in step S5), the control unit 62 determines that a serious alarm has occurred (step S6). Note that when it is determined in step S6 that a serious alarm has occurred, the control unit 62 may, for example, emit a sound or display on the display of the operating device 7 that a serious alarm has occurred. Occurrence may be notified.

When determining that a serious alarm has occurred, the control unit 62 records in the storage unit 61 that a serious alarm has occurred (step S7). Specifically, the control unit 62 records the fact that a serious alarm has occurred in the serious alarm occurrence history AH stored in the storage unit 61. More specifically, the control unit 62 records, for example, a value of "1" in the serious alarm occurrence history AH to record that the serious alarm occurrence flag has been turned "ON".

After that, the control unit 62 stops the vacuum pump 1 as a protection operation (step S8). Note that the information recorded in the serious alarm occurrence history AH is not reset even if the vacuum pump 1 is stopped and the power of the vacuum pump 1 (control device 6) is turned off. That is, the serious alarm occurrence history AH is stored in a storage area of the storage unit 61 that can retain information even if the power supply to the control device 6 is cut off (for example, a storage area of a nonvolatile memory such as an HDD, SSD, or EEPROM). has been done.

By executing steps S1 to S8 above, the control unit 62 issues a serious alarm only when not only the number of occurrences of one type of abnormality but also the number of occurrences of multiple types of abnormality exceeds a predetermined threshold. It can be determined that this has occurred. As a result, it is possible to prevent a serious alarm from being erroneously generated, for example, when the possibility that the vacuum pump 1 will fail is low because the number of occurrences of only one type of abnormality is large and the number of occurrences of other abnormalities is small. .

Further, by generating a serious alarm when each of the number of occurrences of a plurality of types of abnormalities exceeds a predetermined threshold value, it is possible to prompt the user to repair and/or replace the vacuum pump 1. For example, an abnormality related to the vibration of the vacuum pump 1, an abnormality related to the rotation speed of the rotor 4, and an abnormality related to the temperature of the vacuum pump 1 are each related to the accumulation of products, so if a serious alarm is generated, It can be inferred that there is excessive product accumulation, prompting an overhaul to remove the product.

<Vacuum pump startup operation>
Next, the starting operation of the vacuum pump 1 will be explained using FIG. 4. FIG. 4 is a flowchart showing the startup operation of the vacuum pump 1. When the power to the vacuum pump 1 is turned on and the vacuum pump 1 starts to start, the control unit 62 records in the serious alarm occurrence history AH stored in the storage unit 61 that a serious alarm occurred before the current startup. It is determined whether or not it is shown (step S11). Specifically, for example, the control unit 62 determines whether the value of the serious alarm occurrence history AH is "1" and the serious alarm occurrence flag is "ON".

If the serious alarm occurrence history AH does not indicate the occurrence of a serious alarm (“No” in step S11), the control unit 62 operates the vacuum pump 1 in the normal operation mode (step S12). That is, the control unit 62 executes steps S1 to S8 described above.

On the other hand, if the serious alarm occurrence history AH indicates the occurrence of a serious alarm ("Yes" in step S11), the control unit 62 determines that the operation mode of the vacuum pump 1 is the operation restriction mode, and operate in limited operation mode.

Specifically, the control unit 62 first operates the vacuum pump 1 for a predetermined time after startup (step S13). For example, if the target to be evacuated by the vacuum pump 1 is a chamber used in a semiconductor manufacturing process, the control unit 62 controls the vacuum pump 1 for a predetermined number of times after starting the vacuum pump 1. make it work. For example, the control unit 62 operates the vacuum pump 1 for only two hours after starting.

After starting the vacuum pump 1 and operating it for a predetermined period of time, the control unit 62 stops the vacuum pump 1 (step S14).

In this way, by executing steps S11 to S14 described above when starting the vacuum pump 1, the control unit 62 can change the operating mode of the vacuum pump 1 if a serious alarm has occurred before starting the vacuum pump 1. It is possible to prevent the vacuum pump 1 from operating normally and causing a failure by shifting to an operation restriction mode that limits the operation. Further, by operating the vacuum pump 1 for a predetermined time in the operation restriction mode, the vacuum pump 1 can be used for a predetermined time while checking the operating state of the vacuum pump 1.

<How to release a serious alarm>
Hereinafter, a method of canceling the serious alarm after repairing/replacing the vacuum pump 1 when the serious alarm occurs will be explained. A serious alarm can be canceled by the user using the operating device 7 and inputting a dedicated password.

Specifically, when a password is input using the operating device 7, the control unit 62 compares the input password with the release password PW stored in the storage unit 61. As a result of this comparison, when the input password and the release password PW match, the control unit 62 records in the serious alarm occurrence history AH that no serious alarm has occurred. Specifically, for example, the value of the serious alarm occurrence history AH is changed from "1" to "0", and the serious alarm occurrence flag is set to "OFF".

In this way, by allowing the release of a serious alarm using a dedicated password, it is possible to prevent the serious alarm from being released freely. As a result, it is possible to prevent the vacuum pump 1 from operating inadvertently when there is a high possibility that the vacuum pump 1 will fail.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the invention.

In the operation restriction mode, how the operation of the vacuum pump 1 is restricted is not limited to enabling the vacuum pump 1 to operate only for a predetermined period of time, but can be set as appropriate depending on the environment in which the vacuum pump 1 is used.

In the vacuum pump 1 according to the above embodiment, the turbo molecular pump section may be omitted. That is, the vacuum pump 1 may be a thread groove pump.

It will be appreciated by those skilled in the art that the exemplary embodiments described above are specific examples of the following aspects.

(First aspect) The control device is a control device for a vacuum pump that drives a rotor to rotate with a motor to exhaust gas. The control device includes a control section. The control unit counts the number of times each of the plurality of types of abnormalities occurs in the vacuum pump, and generates a serious alarm when the number of times each of the plurality of types of abnormalities occurs exceeds a predetermined threshold.

In the control device according to the first aspect, a serious alarm is generated when the number of occurrences of abnormalities in each of the plurality of types of vacuum pumps exceeds a predetermined threshold. In other words, whether or not to generate a serious alarm is determined based on the number of occurrences of each of the plurality of types of abnormalities. This makes it possible to prevent a serious alarm from being erroneously generated when the number of occurrences of only one type of abnormality is large and the number of occurrences of other types of abnormality is small and the possibility of failure of the vacuum pump is low. Note that the occurrence of a serious alarm does not necessarily require notification to the user (by display, sound, etc.), and may simply be stored in the storage unit.

(Second Aspect) In the control device according to the first aspect, when the number of occurrences of the plurality of types of abnormalities each exceeds a predetermined threshold, the control unit changes the operation mode of the vacuum pump to restart the vacuum pump after stopping the vacuum pump. When this happens, the operation of the vacuum pump is shifted to an operation restriction mode in which the operation of the vacuum pump is restricted more than in normal times.

In the control device according to the second aspect, when the number of occurrences of each of the plurality of types of abnormalities occurring in the vacuum pump exceeds a predetermined threshold, the operation mode of the vacuum pump is shifted to the operation restriction mode. In other words, whether or not to shift to the operation restriction mode is determined based on the number of occurrences of each of the plurality of types of abnormalities. Thereby, when the number of occurrences of only one type of abnormality is large and the number of occurrences of other abnormalities is small and the possibility of failure of the vacuum pump is low, it is possible to prevent the operation mode from erroneously shifting to the operation restriction mode.

(Third Aspect) In the control device according to the second aspect, when the operation mode of the vacuum pump is the operation restriction mode, the control unit causes the vacuum pump to operate for a predetermined period of time after starting, and then to stop the vacuum pump. Good too. In the control device according to the second aspect, the vacuum pump can be used for a predetermined period of time while checking the operating state of the vacuum pump.

(Fourth aspect) In the control device according to the second aspect or the third aspect, the control device may further include a storage unit. In this case, when the control unit generates a serious alarm, it stores in the storage unit a history of serious alarm occurrences indicating that a serious alarm has occurred, and when the vacuum pump is restarted, the history of occurrence of serious alarms indicates that a serious alarm has occurred. If the occurrence of an alarm is indicated, it may be determined that the operation mode of the vacuum pump is the operation restriction mode. In the control device according to the fourth aspect, when a serious alarm occurs, it is stored in the storage unit, so that it is possible to know that a serious alarm has occurred before restarting the vacuum pump, and when the vacuum pump is restarted, The vacuum pump can be operated in a limited operation mode.

(Fifth Aspect) In the control device according to any of the second to fourth aspects, the control unit may cancel the operation restriction mode when a dedicated password is input. In the control device according to the fifth aspect, it is possible to prevent the critical alarm from being canceled freely and prevent the vacuum pump 1 from operating inadvertently when there is a high possibility that the vacuum pump will fail.

(Sixth Aspect) In the control device according to any of the first to fifth aspects, the predetermined threshold value may be changeable. In the control device according to the sixth aspect, the conditions for generating a serious alarm (conditions for transition to operation restriction mode) can be set to be optimal according to the environment in which the vacuum pump is used.

(Seventh Aspect) In the control device according to any one of the first to sixth aspects, the plurality of types of abnormalities are selected from abnormalities related to vibration of the vacuum pump, abnormalities related to the rotational speed of the rotor, and abnormalities related to the temperature of the vacuum pump. There may be at least two abnormalities. In the control device according to the seventh aspect, it is possible to appropriately execute transition to the operation restriction mode (occurrence of a serious alarm) based on the number of occurrences of a plurality of types of abnormalities that lead to failure of the vacuum pump. For example, abnormalities related to vacuum pump vibration, rotor rotation speed, and vacuum pump temperature are all related to product accumulation, so if a serious alarm occurs, It can be assumed that there is excessive deposition, prompting an overhaul to remove the product.

(Eighth Aspect) A control method according to an eighth aspect is a method for controlling a vacuum pump in which a rotor is rotationally driven by a motor to exhaust gas. The control method includes the steps of: counting the number of occurrences of each of the plurality of types of abnormalities occurring in the vacuum pump; and generating a serious alarm when the number of occurrences of each of the plurality of types of abnormalities exceeds a predetermined threshold; Equipped with

In the control method according to the eighth aspect, a serious alarm is generated when the number of occurrences of abnormalities in each of the plurality of types of vacuum pumps exceeds a predetermined threshold. In other words, whether or not to generate a serious alarm is determined based on the number of occurrences of multiple types of abnormalities. Thereby, it is possible to prevent a serious alarm from being erroneously generated when there is a low possibility that the vacuum pump will fail because the number of occurrences of only one type of abnormality is large and the number of occurrences of other abnormalities is small.

Although various embodiments and modifications have been described above, the present invention is not limited to these embodiments. Moreover, each embodiment and modification may be applied individually, or may be used in combination. Other embodiments considered within the technical spirit of the present invention are also included within the scope of the present invention.

1: Vacuum pump 2: Housing 3: Base 4: Rotor 5: Stator 6: Control device 7: Operating device 11: First end 12: Second end 13: Intake port 14: Base end 16: Exhaust port 21 : Shaft 22 : Rotor blade 23 : Rotor cylindrical part 31 : Stator blade 32 : Stator cylindrical part 33 : Housing 41A to 41E : Bearing 42 : Motor 42A : Motor rotor 42B : Motor stator 43 : Rotation speed sensor 44A to 44C : Displacement sensor 45: Motor current measuring device 51: Heater 52: Temperature sensor 53: Heater current measuring device 61: Storage section 62: Control section AH: Critical alarm occurrence history CNT: Abnormal occurrence counter CON: Abnormal occurrence condition PW: Cancellation password RCO: Critical Alarm condition SP1: First internal space SP2: Second internal space

Claims (8)

A control device for a vacuum pump that exhausts gas by rotationally driving a rotor with a motor,
Equipped with a control unit,
The control unit includes:
Counting the number of occurrences of each of the plurality of types of abnormalities that occurred in the vacuum pump,
If the number of occurrences of multiple types of abnormalities each exceeds a predetermined threshold, a serious alarm will be generated.
Control device. When the number of occurrences of each of the plurality of types of abnormalities exceeds a predetermined threshold, the control unit changes the operation mode of the vacuum pump to a normal mode when the vacuum pump is restarted after being stopped. Shift to operation restriction mode that is more restrictive than
The control device according to claim 1. 3. The control device according to claim 2, wherein, when the operation mode of the vacuum pump is the operation restriction mode, the control unit operates the vacuum pump for a predetermined period of time after starting and then stops the vacuum pump. Further equipped with a storage section,
The control unit includes:
When the serious alarm is generated, storing a serious alarm occurrence history indicating that the serious alarm has occurred in the storage unit;
determining that the operation mode of the vacuum pump is the operation restriction mode if the serious alarm occurrence history indicates the occurrence of the serious alarm when the vacuum pump is restarted;
The control device according to claim 2 or 3. The control device according to any one of claims 2 to 4, wherein the control unit cancels the operation restriction mode when a dedicated password is input. The control device according to any one of claims 1 to 5, wherein the predetermined threshold value is changeable. The plurality of types of abnormalities are at least two abnormalities selected from abnormalities related to vibration of the vacuum pump, abnormalities related to the rotation speed of the rotor, and abnormalities related to the temperature of the vacuum pump, according to any one of claims 1 to 6. Control device. A method for controlling a vacuum pump that exhausts gas by rotationally driving a rotor with a motor, the method comprising:
counting the number of occurrences of each of the plurality of types of abnormalities occurring in the vacuum pump;
generating a serious alarm when the number of occurrences of the plurality of types of abnormalities each exceeds a predetermined threshold;
A control method comprising:

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