JP2018204437A - Vacuum pump, vacuum exhaust system and exhaust system controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent filament burnout of an ionization vacuum gauge provided in a vacuum chamber. A vacuum pump 1 is detected by a rotation speed sensor 113 that detects the rotation speed of a pump rotor 110, a signal output terminal 120 connected to a signal input terminal 22 of a vacuum gauge 2, and a rotation speed sensor 113. When the rotation speed is lower than the rated rotation speed of the pump rotor 110 and is equal to or higher than the lower limit rotation speed of energization, an energization on signal for permitting filament energization is generated, and when the rotation speed is less than the lower limit rotation speed for energization, energization off for prohibiting filament energization. A signal generation unit 126 for generating a signal is provided, and an energization on signal and an energization off signal are output from the signal output terminal 120. [Selection diagram] Fig. 2

Description

  The present invention relates to a vacuum pump, a vacuum exhaust system, and an exhaust system controller.

  Generally, when the vacuum chamber is evacuated to a relatively high vacuum, an ionization vacuum gauge is used for pressure measurement. The ionization vacuum gauge is composed of a measuring element and a measuring instrument connected to the measuring element. The probe includes a filament that emits thermoelectrons, a grid that accelerates and collects thermoelectrons, and an ion collector that collects ions of gas molecules ionized by collision with the thermoelectrons. When pressure measurement is performed, the filament is energized and heated, the ion current flowing through the ion collector at that time is measured, and the pressure is estimated based on the magnitude of the ion current.

  The ionization vacuum has a drawback that when the filament is energized at a pressure close to atmospheric pressure, the filament burns out. For this reason, some commercially available measuring instruments are equipped with a protection circuit that prevents the filament from being energized when the pressure is high.

JP 2013-72694 A

  By the way, when high-vacuum measurement is performed while the filament is energized, if the pressure in the chamber rises suddenly due to incorrect operation of the valve or air rush, the filament off operation by the protection circuit is not in time and the filament Could burn out.

A vacuum pump according to a preferred embodiment of the present invention includes a rotation speed detection unit that detects the rotation speed of a pump rotor, a signal output terminal connected to a filament energization control signal input terminal of an ionization vacuum gauge, and the rotation speed detection unit. When the detected rotational speed is equal to or higher than the lower limit rotational speed of the energization lower than the rated rotational speed of the pump rotor, a first filament energization control signal is generated to permit filament energization. A signal generation unit that generates a second filament energization control signal for prohibiting energization, and outputs the first and second filament energization control signals from the signal output terminal.
A vacuum exhaust system according to a preferred embodiment of the present invention is a vacuum exhaust system including the vacuum pump of the above embodiment and an ionization vacuum gauge, and the ionization vacuum gauge is a vacuum chamber evacuated by the vacuum pump. A sensor unit for detecting pressure; a control unit for controlling energization of a filament provided in the sensor unit; and the filament energization control signal input terminal, wherein the control unit includes the first filament energization control signal. Is input, the filament is energized, and when the second filament energization control signal is input, the filament is deenergized.
An evacuation system according to a preferred embodiment of the present invention includes an ionization vacuum gauge having a sensor unit that detects a pressure of a vacuum chamber and a control unit that controls energization of a filament of the sensor unit, and a pump connected to the vacuum chamber. A vacuum pump having a detection unit for detecting the rotational speed information of the rotor, and an exhaust system controller to which the rotational speed information is input from the vacuum pump, the exhaust system controller being based on the rotational speed information When the rotational speed of the pump rotor is determined to be equal to or higher than the lower limit rotational speed of energization lower than the rated rotational speed of the pump rotor, the first filament energization control signal for permitting filament energization If it is determined, the second filament energization control signal for prohibiting filament energization is controlled by the control. The controller of the ionization vacuum gauge energizes the filament when the first filament energization control signal is input, and energizes the filament when the second filament energization control signal is input. To stop.
An evacuation system according to a preferred embodiment of the present invention includes an ionization vacuum gauge having a sensor unit that detects a pressure of a vacuum chamber and a control unit that controls energization of a filament of the sensor unit, and a pump connected to the vacuum chamber. A vacuum pump having a detection unit for detecting rotation speed information of the rotor, and a power supply unit for supplying power to the ionization vacuum gauge of the ionization vacuum gauge, and an exhaust gas to which the rotation speed information is input from the vacuum pump A controller for the system, and the exhaust system controller determines, based on the rotational speed information, that the rotational speed of the pump rotor is equal to or higher than the lower limit rotational speed of energization lower than the rated rotational speed of the pump rotor. Supplies power from the power supply unit, and stops power supply from the power supply unit when it is determined that it is less than the lower limit energization speed.
An exhaust system controller according to a preferred embodiment of the present invention is the exhaust system controller applied to the vacuum exhaust system of the above embodiment.

  According to the present invention, filament burnout of an ionization vacuum gauge provided in a vacuum chamber can be prevented.

FIG. 1 is a diagram showing a vacuum pump mounted on a vacuum apparatus. FIG. 2 is a block diagram showing a schematic configuration of the vacuum pump and the vacuum gauge. FIG. 3 is a diagram illustrating filament energization control. FIG. 4 is a diagram illustrating a second embodiment. FIG. 5 is a diagram illustrating a modification of the second embodiment. FIG. 6 is a view showing a rotation sensorless vacuum pump pivotally supported by a permanent magnet and a ball bearing. FIG. 7 is a block diagram showing a schematic configuration of a vacuum pump including the pump unit shown in FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
-First embodiment-
FIG. 1 is a diagram showing a vacuum pump 1 mounted on a vacuum apparatus. A vacuum pump 1 is connected to the exhaust port 4a of the vacuum chamber 4, and a vacuum gauge 2 is attached to the gauge port 4b. The vacuum pump 1 includes a pump unit 11 having a pump rotor (not shown) and a control unit 12 that drives and controls the pump unit 11. In the present embodiment, a turbo molecular pump is used for the vacuum pump 1, and the back pump 3 is connected to the exhaust port 115 provided in the pump unit 11. In the configuration shown in FIG. 1, the back pump 3 is also used as a roughing pump for the vacuum chamber 4.

  The vacuum gauge 2 includes a power supply terminal 21 and a signal input terminal 22. The signal input terminal 22 is connected to the signal output terminal 120 of the control unit 12 by a signal line 23. The control unit 12 is provided with a display unit 121 for displaying pump information and an operation input unit 122 such as a start switch.

  FIG. 2 is a block diagram showing a schematic configuration of the vacuum pump 1 and the vacuum gauge 2. The vacuum gauge 2 shown in FIG. 2 is called a transducer type vacuum gauge (see, for example, WO2011 / 099238A1), and includes a measuring element 2A that is a sensor unit for detecting pressure, and a power supply unit 2B connected to the measuring element 2A. It is provided integrally. In this embodiment, a transducer type vacuum gauge is described as an example, but the measuring element 2A and the power supply unit 2B are configured separately, that is, the measuring element and the measuring instrument (corresponding to the power supply unit 2B). The same can be applied to the vacuum gauge.

  The measuring element 2A is a Bayard-Alpert type ionization vacuum gauge which is a kind of hot cathode ionization vacuum gauge, and includes three electrodes of a filament 200, a grid 201, and an ion collector 202. When a positive grid voltage is applied to the grid 201 and the filament 200 is energized and heated, thermoelectrons are emitted from the filament 200 toward the grid 201. When the thermal electrons collide with the gas molecules, the gas molecules are ionized by ionization, and positively charged ions are generated. A negative voltage with respect to the filament potential is applied to the ion collector 202, and the generated ions are collected by the ion collector 202.

  The power supply unit 2B is provided with a power supply circuit 203, a control unit 204, and an ammeter 205. DC power is supplied to the power supply circuit 203 via the power supply terminal 21. A filament energization control signal to be described later is input to the control unit 204 via the signal input terminal 22. The ammeter 205 measures the ion current flowing through the ion collector 202 and inputs the detection result to the control unit 204.

  The power supply circuit 203 supplies current to the filament 200 and applies voltage to the grid 201 and the ion collector 202. The control unit 204 controls the power supply circuit 203, calculates pressure based on the ion current measured by the ammeter 205, and controls energization of the filament 200 based on the filament energization control signal input from the signal input terminal 22. Do.

  The pump unit 11 of the vacuum pump 1 includes a pump rotor 110, a magnetic bearing 111 that supports the pump rotor 110 in a non-contact manner, a motor 112 that rotationally drives the pump rotor 110, and a rotation speed sensor 113 that detects the rotation speed of the pump rotor 110. It has. In addition to the signal output terminal 120, the display unit 121, and the operation input unit 122 described above, the control unit 12 includes a bearing control unit 123 that drives and controls the magnetic bearing 111, a motor control unit 124 that drives and controls the motor 112, and a rotation speed calculation. Unit 125 and signal generation unit 126.

  The rotation speed calculation unit 125 calculates the rotation speed of the pump rotor 110 based on the detection signal from the rotation speed sensor 113. The signal generator 126 generates a filament energization control signal as will be described later based on the rotation speed calculated by the rotation speed calculator 125. Specifically, when the rotation speed calculated by the rotation speed calculation unit 125 is less than a predetermined rotation speed n1 (hereinafter referred to as a power supply lower limit rotation speed) set lower than the rated rotation speed n0 of the vacuum pump 1. Outputs a signal for prohibiting filament energization (hereinafter referred to as energization off signal) as a filament energization control signal. On the other hand, when the rotation speed is equal to or higher than the energization lower limit rotation speed n1, a signal for permitting filament energization (hereinafter referred to as an energization on signal) is output as a filament energization control signal.

  As a method for setting the energization lower limit rotational speed n1, for example, the vacuum pump 1 is connected to a standard vacuum chamber, and an actual air entry experiment is performed to obtain correlation data between the pressure and the rotational speed. In this case, the vacuum gauge for measuring the pressure is not an ionization vacuum gauge but a vacuum gauge of another type capable of measuring up to the vicinity of atmospheric pressure. And the rotation speed which can prevent the filament burning of an ionization vacuum gauge from the acquired correlation data is set to the electricity supply minimum rotation speed n1.

  FIG. 3 is a diagram illustrating filament energization control in the present embodiment. FIG. 3 shows the operation from the start to the stop of the vacuum pump 1, and shows the case where there is an air rush during steady operation and the pressure suddenly increases. FIG. 3A shows the rotational speed of the pump rotor from start to stop, and the horizontal axis represents the elapsed time from the start of the pump. Similarly, FIG. 3B shows the pressure measurement value of the vacuum chamber 4 by the vacuum gauge 2, and FIG. 3C shows the filament energization control signal.

  First, with reference to Fig.3 (a), the change of the rotation speed from a starting to a stop is demonstrated. When the vacuum pump 1 is started by operating the operation input unit 122 of the control unit 12 at time t = t0, the pump rotor 110 acceleration operation by the motor 112 is started, and the rotational speed increases with the passage of time. When the rated rotational speed n0 is reached at time t2, the acceleration operation is shifted to the rated rotational operation for maintaining the rotational speed at the rated rotational speed n0. Time t1 is a time during which the rotational speed reaches the lower limit rotational speed n1 during the acceleration operation.

  Atmospheric rush occurs at time t3. In this case, since the chamber pressure greatly increases due to a rapid gas inflow, the motor control unit 124 cannot maintain the rotation speed at the rated rotation speed n0, and the rotation speed greatly decreases. The rotation speed becomes the energization lower limit rotation speed n1 at time t4. Thereafter, when the gas inflow is stopped, a restarting operation for accelerating the reduced rotational speed to the rated rotational speed n0 is performed. As a result, the rotational speed reaches the energization lower limit rotational speed n1 at time t5, and reaches the rated rotational speed n0 at time t6. Thereafter, when the operation is shifted to the deceleration operation by the stop operation at time t7, the rotational speed is decreased.

  In response to an operating situation that shows a change in the rotational speed as shown in FIG. 3A, the signal generator 126 provided in the control unit 12 outputs a filament energization control signal as shown in FIG. The filament energization control signal is a signal that takes two states, a high state and a low state. The high state corresponds to the above-described energization on signal, and the low state corresponds to the energization off signal. Since the rotation speed is equal to or greater than the lower limit rotation speed n1 from time t0 to time t1 and from time t5 to time t7, an energization on signal is output as the filament energization control signal. On the other hand, from time t0 to time t1 and from time t4 to time t5, since the rotational speed is less than the energization lower limit rotational speed n1, an energization off signal is output as a filament energization control signal.

  In addition, during the period t7 to t8 after the stop operation, the energization off signal is output as the filament energization control signal. Since there is no need to acquire a pressure value after the stop operation, the filament energization is turned off. Of course, even after the stop operation, the energization on signal is output when the rotation speed is equal to or greater than the energization lower limit rotation speed n1, and the energization off signal is output when the rotation speed is less than the energization lower limit rotation speed n1. good.

  As a result, the pressure measurement value is acquired only in the period (time t1 to t4, time t5 to t7) in which the filament energization control signal becomes the energization on signal, as shown by the solid line in FIG. The dotted line indicates the chamber pressure during the period when the energization off signal is output. When an atmospheric rush occurs at time t3, the chamber pressure rapidly increases. However, since filament energization is turned off at time t4, filament burnout can be prevented.

(C1) As described above, in this embodiment, the vacuum pump 1 includes the signal output terminal 120 connected to the signal input terminal 22 of the vacuum gauge 2, and the pump rotor detected by the rotation speed calculation unit 125. When the rotational speed of 110 is equal to or higher than the lower limit rotational speed n1 of energization lower than the rated rotational speed n0, an energization on signal that permits filament energization, and when less than the lower limit rotational speed n1, the energization off signal prohibits filament energization. Is generated by the signal generator 126 and output from the signal output terminal 120. Therefore, by inputting the filament energization control signal output from the signal output terminal 120 to the signal input terminal 22 of the vacuum gauge 2, it is possible to appropriately perform the filament energization off operation when the pressure rises.

  In the conventional configuration in which the filament energization is turned off after waiting for the chamber pressure to rise to the pressure at which the protection circuit is activated, the energization may not be in time when the pressure suddenly rises, such as an air rush. . However, in this embodiment, since the filament energization off operation is performed based on the rotation speed of the vacuum pump 1, it is easy to turn off the energization at a pressure timing at which the filament does not burn out, and filament burnout can be prevented.

  By the way, in the figure of FIG.3 (b), before exhaust_gas | exhaustion by a back pump is performed in a pump stop state, a chamber pressure is atmospheric pressure. Further, immediately after the start of pump acceleration or immediately before the stop operation, the vacuum pressure of the vacuum pump 1 is almost zero, so the chamber pressure is relatively high. Therefore, when a conventional vacuum gauge is used, if the power of the vacuum gauge 2 is accidentally turned on during these periods, there is a high possibility that the filament will burn out. However, in the present embodiment, even if the power of the vacuum gauge 2 is on during the acceleration operation or the stop operation, the filament energization is turned off if the rotation speed is less than the lower energization rotation speed n1. , Filament burning during such a period can be reliably prevented.

(C2) Also, by applying a vacuum exhaust system including the vacuum gauge 2 having the signal input terminal 22 for filament energization control signal input and the vacuum pump 1 described above to the vacuum chamber 4 shown in FIG. Burnout of the filament 200 of the probe 2A for measuring the chamber pressure can be prevented.

-Second Embodiment-
FIG. 4 is a diagram illustrating a second embodiment. In the second embodiment, the system external controller 5 is further provided in the vacuum exhaust system including the vacuum pump 1 and the vacuum gauge 2. Pump information indicating the state of the vacuum pump 1 is input from the control unit 12 to the external controller 5, and information regarding the rotational speed is input from the rotational speed calculation unit 125. A signal for remotely operating the vacuum pump 1 from the external controller 5 is input from the external controller 5 to the control unit 12.

  The pump information includes various information related to the motor current value, the motor temperature, the pump temperature, the pump operation state (acceleration, stop operation, abnormal state, etc.), and the like. The external controller 5 is provided with a display unit 51 for displaying the above-described pump information and rotation speed, and an operation unit 52 for remotely operating the vacuum pump 1. Further, the external controller 5 is also provided with a signal generator 53 that generates a filament energization control signal based on the rotation speed information input from the rotation speed calculator 125. In the present embodiment, the rotational speed calculation unit 125 outputs a rotational speed signal as rotational speed information.

  The filament energization control signal generated by the signal generation unit 53 is input to the control unit 204 via the signal input terminal 22 of the vacuum gauge 2. The signal generator 53 outputs a signal similar to the filament energization control signal shown in FIG. 3C, and the filament energization operation of the vacuum gauge 2 is performed in the same manner as in FIG.

(C3) In the second embodiment, as shown in FIG. 4, the evacuation system includes a gauge 2 having a filament, and a vacuum gauge 2 having a control unit 204 that controls energization of the filament 200 of the gauge 2A. , A vacuum pump 1 having a rotation speed sensor 113 for detecting rotation speed information of the pump rotor 110 and a rotation speed calculation unit 125, and an external controller 5 to which the rotation speed information is input from the vacuum pump 1.

  When the external controller 5 determines that the rotational speed of the pump rotor 110 is equal to or higher than the lower limit rotational speed n1 of the pump rotor that is lower than the rated rotational speed n0 of the pump rotor based on the rotational speed information, When it is determined that the ON signal is less than the energization lower limit rotation speed n1, an energization OFF signal for prohibiting filament energization is output to the control unit 204. The controller 204 energizes the filament 200 when the energization on signal is input, and stops energization of the filament 200 when the energization off signal is input.

  Also in the second embodiment, as in the case of the first embodiment, when the rotation speed of the pump rotor 110 is less than the lower limit rotation speed n1, the energization of the filament 200 is stopped. Thus, even when the pressure increases rapidly, the filament 200 can be prevented from being burned out. In the second embodiment, the external controller 5 inputs the filament energization control signal to the vacuum gauge 2 based on the rotation speed information output from the vacuum pump 1, so that the vacuum pump is capable of outputting the rotation speed information. Then, an evacuation system as shown in FIG. 4 can be easily configured.

(Modification)
FIG. 5 is a diagram illustrating a modification of the second embodiment. In the second embodiment, the external controller 5 includes a DC supply unit 54 that supplies DC power to the vacuum gauge 2 instead of the signal generation unit 53 of FIG. The DC supply unit 54 supplies DC power during the energization period (t1 to t4, t5 to t7) shown in FIG. 3B, and DC during the non-energization period (t0 to t1, t4 to t5, t7 to t8). Stop supplying power. When the DC power to the vacuum gauge 2 is stopped, the current supply to the filament 200 is also stopped, so that the filament 200 can be prevented from being burned out.

(C4) In the modification, when the external controller 5 determines that the rotational speed of the pump rotor 110 is less than the lower limit rotational speed n1 that is lower than the rated rotational speed n0 based on the rotational speed information input from the vacuum pump 1. Since the power supply from the DC supply unit 54 to the vacuum gauge 2 is stopped, the filament 200 can be prevented from being burned even in a situation where the chamber pressure rapidly increases.

  In the example shown in FIG. 5, the rotational speed information is input to the external controller 5. However, as in the case of FIG. 4, a filament energization control signal is output from the vacuum pump 1, and the external controller 5 The power supply to the vacuum gauge 2 may be controlled based on the control signal. That is, when an energization on signal is input from the vacuum pump 1 to the external controller 5, DC power is supplied to the vacuum gauge 2, and when an energization off signal is input, the supply of DC power is stopped.

  In the embodiment described above, a vacuum pump that is a magnetic bearing type and further detects the number of rotations of the pump rotor 110 by a rotation sensor has been described as an example. However, a rotation that does not include a ball bearing type vacuum pump or a rotation sensor. It can also be applied to a sensorless vacuum pump.

  For example, as shown in FIG. 6, the present invention can also be applied to a rotary sensorless vacuum pump that supports a pump rotor with a permanent magnet and a ball bearing. In the pump unit 11 shown in FIG. 6, the pump rotor 110 is supported by a magnetic bearing part 116 using permanent magnets 116 a and 116 b and a ball bearing 118. The pump rotor 110 is rotationally driven by a motor 112. The pump rotor 110 is provided with a plurality of stages of rotating blades 114a and a cylindrical portion 117a. On the other hand, a plurality of stages of fixed blades 114b are provided for the rotating blades 114a, and a stator 117b is provided for the cylindrical portion 117a.

  FIG. 7 is a block diagram showing a schematic configuration of the vacuum pump 1 including the pump unit shown in FIG. The control unit 12 is provided with the signal output terminal 120, the display unit 121, the operation input unit 122, the motor control unit 124, and the signal generation unit 126 described above. The motor control unit 124 is a rotation sensorless motor control unit, and includes a sine wave drive control unit 300, an inverter 301, a current detection unit 302, and a voltage detection unit 303. The rotation sensorless motor control is a general technique as disclosed in, for example, Japanese Patent Application Laid-Open No. 2014-93819, and detailed description thereof is omitted here.

  The motor current value detected by the current detection unit 302 and the motor terminal voltage value detected by the voltage detection unit 303 are input to the sine wave drive control unit 300. The sine wave drive control unit 300 is provided with a rotation speed / magnetic pole position estimation unit 310 as a rotation number detection unit that detects the rotation number of the pump rotor 110. The rotation speed / magnetic pole position estimation unit 310 estimates the rotation speed ω and the magnetic pole position θ of the motor 112 based on the motor current value and the motor terminal voltage value. The sine wave drive control unit 300 outputs a PWM control signal for on / off control of a switching element (not shown) of the inverter 301 based on the rotation speed ω and the magnetic pole position θ estimated by the rotation speed / magnetic pole position estimation unit 310. Generate. The signal generator 126 generates the filament energization control signal as described above based on the rotation speed ω estimated by the rotation speed / magnetic pole position estimation unit 310.

  The vacuum pump 1 shown in FIG. 7 corresponds to the vacuum pump 1 shown in FIG. 2, and the control unit 12 includes a signal generator 126. However, like the vacuum pump 1 shown in FIGS. 4 and 5, the signal generator 126 is omitted, and the rotational speed information (the rotational speed ω and the magnetic pole position θ) estimated by the rotational speed / magnetic pole position estimating unit 310 is external controller. 5 may be used.

  Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention. For example, in the above-described embodiment, the vacuum pump 1 is a turbo molecular pump. However, the vacuum pump 1 is not limited to the turbo molecular pump as long as the rotor is evacuated by rotating the rotor at a high speed.

  DESCRIPTION OF SYMBOLS 1 ... Vacuum pump, 2 ... Vacuum gauge, 2A ... Measuring element, 2B ... Power supply part, 3 ... Back pump, 4 ... Vacuum chamber, 5 ... External controller, 21 ... Power supply terminal, 22 ... Signal input terminal, 53 ... Signal generation 54, DC supply unit, 113, rotation speed sensor, 120, signal output terminal, 125, rotation speed calculation unit, 126, signal generation unit, 200, filament, 203, power supply circuit, 204, control unit, 310, rotation Speed / magnetic pole position estimator, n0 ... rated speed, n1 ... energization lower limit speed

Claims (5)

A rotational speed detector for detecting the rotational speed of the pump rotor;
A signal output terminal connected to the filament energization control signal input terminal of the ionization vacuum gauge;
When the rotational speed detected by the rotational speed detection unit is equal to or higher than the lower limit rotational speed of energization lower than the rated rotational speed of the pump rotor, a first filament energization control signal for permitting filament energization is generated, A signal generation unit that generates a second filament energization control signal that prohibits filament energization in the case of less than,
A vacuum pump that outputs the first and second filament energization control signals from the signal output terminal. A vacuum pump according to claim 1;
An evacuation system comprising an ionization vacuum gauge,
The ionization gauge is
A sensor unit for detecting a pressure of a vacuum chamber exhausted by the vacuum pump;
A control unit for controlling energization of the filament provided in the sensor unit;
The filament energization control signal input terminal,
The evacuation system, wherein the control unit energizes the filament when the first filament energization control signal is input, and stops energization of the filament when the second filament energization control signal is input. An ionization vacuum gauge having a sensor unit for detecting the pressure of the vacuum chamber, and a control unit for controlling energization of the filament of the sensor unit;
A vacuum pump connected to the vacuum chamber and having a detector for detecting rotational speed information of the pump rotor;
An exhaust system controller to which the rotational speed information is input from the vacuum pump,
The exhaust system controller permits the filament energization when it determines that the rotation speed of the pump rotor is equal to or higher than the lower limit rotation speed of the pump rotor lower than the rated rotation speed of the pump rotor based on the rotation speed information. When the filament energization control signal is determined to be less than the energization lower limit rotation speed, a second filament energization control signal for prohibiting filament energization is output to the control unit, respectively.
The controller of the ionization vacuum gauge energizes the filament when the first filament energization control signal is input, and stops energization of the filament when the second filament energization control signal is input. Vacuum exhaust system. An ionization vacuum gauge having a sensor unit for detecting the pressure of the vacuum chamber, and a control unit for controlling energization of the filament of the sensor unit;
A vacuum pump connected to the vacuum chamber and having a detector for detecting rotational speed information of the pump rotor;
A power supply unit for supplying power to the ionization vacuum gauge of the ionization vacuum gauge, and an exhaust system controller to which the rotation speed information is input from the vacuum pump,
When the exhaust system controller determines that the rotational speed of the pump rotor is equal to or higher than the lower limit rotational speed of energization lower than the rated rotational speed of the pump rotor based on the rotational speed information, power is supplied from the power supply unit. An evacuation system that supplies power and stops power supply from the power supply unit when it is determined that the rotation speed is less than the lower limit of energization.   An exhaust system controller applied to the vacuum exhaust system according to claim 3.

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