Vacuum pump and controller

Abstract

To provide a vacuum pump from which temperature control means can be inspected or replaced at appropriate timing and which can prevent unexpected stoppage and suppress maintenance cost, and to provide a controller for controlling the same.SOLUTION: A vacuum pump 10 for evacuating a gas from a device to be evacuated includes: temperature control means for controlling temperature of a predetermined part of the vacuum pump 10 to be a predetermined temperature; output control means 205 for operating the temperature control means; and information output means 210 for outputting information relating to ON / OFF of the temperature control means which can be acquired from the output control means 205.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vacuum pump and a controller. [Background technology]

[0002] Vacuum pumps are generally used for exhausting the interior of vacuum chambers installed in semiconductor devices such as CVD devices. In particular, turbomolecular pumps are widely used because they produce little residual gas and are easy to maintain.

[0003] The semiconductor manufacturing process includes steps in which various process gases are applied to the semiconductor substrate, and turbomolecular pumps are used not only to create a vacuum inside the chamber of the semiconductor device, but also to evacuate the process gas from inside the chamber.

[0004] In order to enhance the reactivity of process gas, the process gas may be introduced into the chamber at a high temperature. In such a case, the temperature of the process gas being exhausted is lowered and the pressure is increased, so that the gas sublimes and solidifies, and the product is precipitated. That is, when this type of process gas sublimes in the turbomolecular pump, the solidified product adheres to the inside of the turbomolecular pump and gradually accumulates, narrowing the pump flow path and reducing the performance of the turbomolecular pump.

[0005] In order to cope with such a problem, a heater or the like that switches the energization state by a relay has been incorporated in the turbo molecular pump to heat the portion where deposits are likely to accumulate to a predetermined temperature. In this case, as shown in FIG. 8 (a system configuration diagram of a conventional vacuum pump (turbo molecular pump)), the temperature of the turbo molecular pump is measured on the side of the TMS thermometer connected to the TMS temperature sensor, and the measured value is compared with the set temperature to control the output to the heater or the like. On the other hand, if the heat from the heater or the like diffuses and the temperature of the turbo molecular pump rises, it will affect the electronic circuit incorporated therein. In addition, as the temperature rises, the magnetic force of the permanent magnet used in the motor of the rotor in the pump may decrease or the electromagnet winding may break, so water-cooled pipes are arranged around these and the flow of cooling water is controlled by valves or the like (see, for example, Patent Document 1). In this way, some conventional vacuum pumps are incorporated with temperature adjustment means (heaters, relays, water-cooled pipes, valves, etc.) for setting a predetermined portion of the vacuum pump to a predetermined temperature. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2003-148379 A Summary of the Invention [Problem to be solved by the invention]

[0007] Conventionally, such vacuum pumps have a protection function processor shown in Fig. 8 that compares the temperature measured by the TMS temperature measurement unit with the allowable temperature to notify of high temperature overheating abnormalities / warnings, temperature rise abnormalities, low temperature abnormalities, and open / short circuit abnormalities, but they have sometimes continued to be used until they malfunction without taking into consideration the lifespan of relays and valves (number of ON / OFF cycles and ON / OFF times). If a relay or valve breaks down, the vacuum pump may become abnormally hot or cold, which may result in the vacuum pump suddenly stopping due to some malfunction.

[0008] If the vacuum pump stops during operation, there is a concern that it could affect the quality of semiconductors being manufactured, for example, so in order to prevent such unexpected vacuum pump shutdowns, some systems operate by periodically replacing relays and valves regardless of how often the pump is operated. However, this results in increased maintenance costs, as relays and valves are replaced before they have reached the end of their service life.

[0009] In view of these circumstances, the present invention aims to provide a vacuum pump and a controller for controlling the same, in which it is possible to inspect and replace temperature adjustment means for maintaining a specified temperature at a specified portion of the vacuum pump at an appropriate time, thereby preventing the occurrence of unexpected stoppages, etc., and reducing maintenance costs. [Means for solving the problem]

[0010] The present invention relates to a vacuum pump for exhausting gas from an apparatus to be evacuated, the vacuum pump comprising: a temperature adjustment means for setting a predetermined temperature at a predetermined portion of the vacuum pump; an output control means for operating the temperature adjustment means; and a control circuit for controlling the temperature adjustment means based on information regarding ON / OFF of the temperature adjustment means obtained from the output control means. Calculating at least two of the ON-maintaining interval time, the OFF-maintaining interval time, and the cycle interval time which is the sum of the ON-maintaining interval time and the OFF-maintaining interval time of the temperature adjustment means, and further an accumulative count interval measuring unit that calculates at least two of an averaged ON maintenance interval time of the temperature adjustment means, an averaged OFF maintenance interval time, and an averaged cycle interval time which is the sum of the averaged ON maintenance interval time and the averaged OFF maintenance interval time; At least two of the ON maintenance interval time, the OFF maintenance interval time, and the period interval time A recording means for recording the The cumulative count interval measuring unit obtained from R The ON-maintained interval time during which the averaging process was performed, the OFF-maintained interval time during which the averaging process was performed, and the periodic interval time during which the averaging process was performed ofand an information output means for outputting at least two of the information output means and the cumulative count interval measurement means, in which, when a time when the temperature adjustment means changes from an OFF state to an ON state is defined as T1, a time when the temperature adjustment means changes from an ON state to an OFF state after time T1 is defined as T2, and a time when the temperature adjustment means changes from an OFF state to an ON state after time T2 is defined as T3, the cumulative count interval measurement means calculates at least two of an ON maintenance interval time T2-T1 obtained by subtracting time T1 from time T2, an OFF maintenance interval time T3-T2 obtained by subtracting time T2 from time T3, and a periodic interval time T3-T1 obtained by subtracting time T1 from time T3, and the ON maintenance interval time obtained by adding the most recent (n-1) ON maintenance interval times recorded in the recording means to the T3-T2 OFF maintenance interval time obtained by dividing the sum of the OFF maintenance interval times by n and the averaging process is performed; and the OFF maintenance interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the T3-T2 OFF maintenance interval time obtained by dividing the sum of the OFF maintenance interval times by n and the averaging process is performed; and the T3-T1 period interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the T3-T1 period interval time and dividing the sum of the

[0011] In such a vacuum pump, the information output means 、 It is preferable to output information regarding the number of times the temperature adjustment means is turned ON or OFF.

[0013] The present invention also provides a controller for controlling a vacuum pump body that exhausts gas from an apparatus to be evacuated, the vacuum pump body including a temperature adjustment means for adjusting a predetermined portion of the vacuum pump body to a predetermined temperature, the controller including an output control unit for operating the temperature adjustment means, and a controller for controlling the temperature adjustment means based on information regarding ON / OFF of the temperature adjustment means obtained from the output control unit. Calculating at least two of the ON-maintaining interval time, the OFF-maintaining interval time, and the cycle interval time which is the sum of the ON-maintaining interval time and the OFF-maintaining interval time of the temperature adjustment means, and furtheran accumulative count interval measuring unit that calculates at least two of an averaged ON maintenance interval time of the temperature adjustment means, an averaged OFF maintenance interval time, and an averaged cycle interval time which is the sum of the averaged ON maintenance interval time and the averaged OFF maintenance interval time; At least two of the ON maintenance interval time, the OFF maintenance interval time, and the period interval time A recording means for recording the The cumulative count interval measuring unit obtained from R The ON-maintained interval time during which the averaging process was performed, the OFF-maintained interval time during which the averaging process was performed, and the periodic interval time during which the averaging process was performed of and an information output unit which outputs at least two of the information output units, wherein the cumulative count interval measurement unit calculates at least two of an ON maintenance interval time T2-T1 obtained by subtracting time T1 from time T2, an OFF maintenance interval time T3-T2 obtained by subtracting time T2 from time T3, and a periodic interval time T3-T1 obtained by subtracting time T1 from time T3, where T1 is the time when the temperature adjustment means changes from an OFF state to an ON state, T2 is the time when the temperature adjustment means changes from an ON state to an OFF state that is closest to time T1 after time T1, and T3 is the time when the temperature adjustment means changes from an OFF state to an ON state that is closest to time T2 after time T2, and the ON maintenance interval time obtained by adding the most recent (n-1) ON maintenance interval times recorded in the recording means to the T3-T2 OFF maintenance interval time obtained by dividing the sum of the OFF maintenance interval times by n and the averaging process is performed; and the OFF maintenance interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the T3-T2 OFF maintenance interval time obtained by dividing the sum of the OFF maintenance interval times by n and the averaging process is performed; and the T3-T1 period interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the T3-T1 period interval time and dividing the sum of the Effect of the Invention

[0014] According to the vacuum pump and controller of the present invention, it is possible to inspect and replace the temperature adjustment means at appropriate times based on information regarding the ON / OFF status of the temperature adjustment means output from the information output means, thereby preventing unexpected stoppages of the vacuum pump and reducing maintenance costs. [Brief description of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a vacuum pump body according to an embodiment of the present invention; [Diagram 2] 1 is a system configuration diagram of a vacuum pump according to an embodiment of the present invention. [Diagram 3] 4 is a flowchart showing the operation of a vacuum pump according to an embodiment of the present invention. [Figure 4] 11 is a diagram showing an ON-maintain interval time, an OFF-maintain interval time, and a cycle interval time. FIG. [Diagram 5] 11 is a diagram showing the relationship between the measured temperature and the time when the temperature adjustment means is turned ON / OFF. FIG. [Figure 6] 6 is a table showing the ON maintaining interval time, the OFF maintaining interval time, and the periodic interval time (all of which are averaged) of OD1 and OD2 shown in FIG. 5. [Figure 7] 3 is a modified example of the system configuration diagram shown in FIG. 2. [Figure 8] FIG. 1 is a system configuration diagram of a conventional vacuum pump (turbomolecular pump). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of a vacuum pump and a controller according to the present invention will be described with reference to the drawings. The vacuum pump of this embodiment is a turbomolecular pump 10, which is composed of a pump body 100 and a controller (control device) 200 as shown in Figures 1 and 2. The turbomolecular pump 10 of this embodiment has the pump body 100 connected to an apparatus to be evacuated (not shown) such as a semiconductor device, and exhausts process gas from within a chamber of the apparatus to be evacuated under the control of the controller 200.

[0017] First, we will explain the pump main body 100. The pump main body 100 has a cylindrical outer cylinder 127, and an intake port 101 is provided at the upper end of the outer cylinder 127. Inside the outer cylinder 127, there is provided a rotor 103 having a plurality of rotors 102a, 102b, 102c, etc. made of turbine blades formed radially and in multiple stages on the periphery for sucking in and exhausting process gas.

[0018] A rotor shaft 113 is attached to the center of the rotating body 103. This rotor shaft 113 is supported in the air and its position is controlled by, for example, a so-called five-axis controlled magnetic bearing.

[0019] In this embodiment, the upper radial electromagnets 104 are composed of four electromagnets, and these electromagnets are arranged in pairs on X-axis and Y-axis which are mutually perpendicular coordinate axes in the radial direction of the rotor shaft 113. The pump body 100 is also provided with an upper radial sensor 107 consisting of four electromagnets located close to the upper radial electromagnets 104. The upper radial sensor 107 detects the radial displacement of the rotating body 103 and sends the information to the controller 200.

[0020] Here, the controller 200 controls the excitation of the upper radial electromagnet 104 via a compensation circuit having a PID adjustment function based on the displacement signal detected by the upper radial sensor 107, and adjusts the upper radial position of the rotor shaft 113.

[0021] The rotor shaft 113 is made of, for example, a high magnetic permeability material (iron, etc.), and is adapted to be attracted by the magnetic force of the upper radial electromagnets 104. The magnetic forces are adjusted independently in the X-axis and Y-axis directions.

[0022] In addition, a lower radial electromagnet 105 and a lower radial sensor 108 are arranged in the same manner as the upper radial electromagnet 104 and the upper radial sensor 107, and adjust the lower radial position of the rotor shaft 113 in the same manner as the upper radial position.

[0023] Furthermore, axial electromagnets 106A and 106B are arranged above and below a circular metal disk 111 provided at the bottom of rotor shaft 113. Metal disk 111 is made of a high magnetic permeability material such as iron. An axial sensor 109 is provided to detect the axial displacement of rotor shaft 113, and an axial displacement signal is sent to controller 200.

[0024] The axial electromagnets 106A and 106B are controlled to be excited based on the axial displacement signal through a compensation circuit having a PID adjustment function of the controller 200. The axial electromagnets 106A and 106B attract the metal disk 111 upward and downward, respectively, by magnetic forces.

[0025] In this way, the controller 200 appropriately adjusts the magnetic forces exerted by the axial electromagnets 106A, 106B on the metal disk 111, magnetically levitating the rotor shaft 113 in the axial direction and holding it in space without contact.

[0026] The motor 121 has a plurality of magnetic poles arranged circumferentially so as to surround the rotor shaft 113. Each magnetic pole is controlled by a controller 200 so as to rotate the rotor shaft 113 via an electromagnetic force acting between the magnetic pole and the rotor shaft 113.

[0027] A plurality of fixed blades 123a, 123b, 123c... are disposed with a small gap between the rotor blades 102a, 102b, 102c.... Each of the rotor blades 102a, 102b, 102c... is formed so as to be inclined at a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113 in order to transport the molecules of the exhausted process gas downward by collision with them.

[0028] Similarly, the stator blades 123a, 123b, 123c... are formed at a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113, and are arranged alternately with the stages of the rotor blades 102a, 102b, 102c... toward the inside of the outer cylinder 127. One end of the stator blades 123a, 123b, 123c... is supported in a state where it is inserted between the multiple stacked stator blade spacers 125a, 125b, 125c...

[0029] The fixed wing spacers 125a, 125b, 125c... are ring-shaped members and are formed from metals such as aluminum, iron, stainless steel, copper, etc., or alloys containing these metals as components.

[0030] An outer cylinder 127 is fixed to the outer periphery of the fixed vane spacers 125a, 125b, 125c, etc. with a small gap therebetween. A base portion 129 is disposed at the bottom of the outer cylinder 127, and a threaded spacer 131 is disposed between the lower portions of the fixed vane spacers 125a, 125b, 125c, etc. and the base portion 129. An exhaust port 133 is formed in the lower portion of the threaded spacer 131 in the base portion 129, and is connected to the outside.

[0031] The threaded spacer 131 is a cylindrical member made of metal such as aluminum, copper, stainless steel, iron, or an alloy containing these metals, and has a plurality of helical thread grooves 131a engraved on its inner peripheral surface. The helical direction of the thread grooves 131a corresponds to the direction in which the molecules of the process gas exhausted in the rotation direction of the rotor 103 are transported toward the exhaust port 133.

[0032] Rotating blade 102d hangs down from the lowest part of rotor 103, continuing from rotors 102a, 102b, 102c, etc. The outer circumferential surface of rotating blade 102d is cylindrical, and protrudes toward the inner circumferential surface of threaded spacer 131, and is adjacent to the inner circumferential surface of threaded spacer 131 with a specified gap therebetween.

[0033] The base portion 129 is a disk-shaped member that constitutes the base of the turbo molecular pump 10, and is generally made of a metal such as iron, aluminum, or stainless steel.

[0034] The base portion 129 not only physically holds the turbo molecular pump 10 but also functions as a heat conduction path, so it is preferable to use a metal that is rigid and has high thermal conductivity, such as iron, aluminum, or copper.

[0035] In the pump body 100 configured as described above, when the rotor blades 102a, 102b, 102c, etc. are driven by the motor 121 and rotate together with the rotor shaft 113, the process gas from the device to be evacuated is sucked in through the intake port 101 by the action of the rotor blades 102a, 102b, 102c, etc. and the fixed blades 123a, 123b, 123c, etc.

[0036] The process gas sucked in from the intake port 101 passes between the rotors 102a, 102b, 102c... and the stators 123a, 123b, 123c... and is transferred to the base portion 129. At this time, the temperature of the rotors 102a, 102b, 102c... rises due to frictional heat generated when the process gas comes into contact with or collides with the rotors 102a, 102b, 102c... and due to conduction or radiation of heat generated by the motor 121, but this heat is transferred to the stators 123a, 123b, 123c... by radiation or conduction by gas molecules of the process gas, etc.

[0037] The fixed vane spacers 125a, 125b, 125c... are joined to each other at their outer peripheries, and transmit heat received by the fixed vanes 123a, 123b, 123c... from the rotors 102a, 102b, 102c... and frictional heat generated when the process gas comes into contact with or collides with the fixed vanes 123a, 123b, 123c... to the outer cylinder 127 and the threaded spacer 131. The process gas transported to the threaded spacer 131 is then guided by the thread groove 131a to the exhaust port 133 and exhausted from the pump body 100.

[0038] However, as described above, when the temperature of the process gas is decreased or the pressure is increased, the process gas may sublimate and become solid, and the product may be precipitated. In the pump body 100, the temperature may be low around the exhaust port 133. In particular, the gap is narrow around the rotor 102d and the threaded spacer 131, so that the flow path is easily narrowed by the precipitated product of the process gas. For this reason, in the pump body 100 of this embodiment, for example, a heater, a circular water-cooling tube, a temperature sensor (e.g., a thermistor), etc. are arranged on the outer periphery of the base part 129, and based on the signal of this temperature sensor, heating by the heater and cooling by the water-cooling tube are controlled so that the temperature of the base part 129 is kept at a temperature (set temperature) at which the product does not precipitate (hereinafter referred to as "TMS control"; TMS; Temperature Management System). Here, if the set temperature in the TMS control becomes high, the product is less likely to deposit, so it is desirable to set the set temperature as high as possible.

[0039] On the other hand, when the temperature of the base part 129 rises, the temperature of the electronic circuit attached to the base part also rises. If the temperature rises higher than expected, for example due to a fluctuation in the exhaust load, the temperature may exceed the allowable temperature of the semiconductor memory provided in the electronic circuit, and the maintenance information data recorded in this memory, such as the control parameters, pump start-up time, and error history, may be lost. If the maintenance information data is lost, it will become impossible to determine the timing of maintenance inspections, which will cause a major problem.

[0040] In addition, if the temperature of base portion 129 becomes higher than expected, the current flowing through the electromagnetic windings that form the magnetic poles of motor 121 may increase, exceeding the allowable temperature of the windings. In such a case, there is a risk that the electromagnetic windings will break and the motor will stop.

[0041] For this reason, in pump body 100, heaters and water-cooled pipes are disposed in appropriate positions according to the parts where the temperature should be high (for example, near rotor 102d or threaded spacer 131) and the parts where the temperature should be kept low (for example, near the electronic circuit or motor 121), and controller 200 switches relays that switch the energized state of the heater and valves connected to the water-cooled pipes ON / OFF at appropriate times to maintain predetermined parts of pump body 100 at a predetermined temperature. Note that in this embodiment, the "temperature adjustment means" in this specification corresponds to the heater, relay, cold water pipe, valve, etc. described above.

[0042] Here, the controller 200 will be described in detail with reference to Fig. 2. The controller 200 is configured to realize the functions described below using various electronic components and a board on which the electronic components are mounted.

[0043] The magnetic bearing control unit 201 controls the magnetic bearings in the pump body 100 (controls the axial electromagnets 106A, 106B in FIG. 1), and the motor drive control unit 202 controls the motor (controls the motor 121 in FIG. 1). The TMS temperature measurement unit 203 measures the temperature of a predetermined portion of the pump body 100 based on an output signal from a temperature sensor for executing TMS control (hereinafter referred to as the "TMS temperature sensor").

[0044] The magnetic bearing control unit 201, the motor drive control unit 202, and the TMS temperature measurement unit 203 are connected to a protection function processing unit 204. The protection function processing unit 204 monitors whether or not an abnormality has occurred in the pump main body 100 based on information about the magnetic bearing obtained from the magnetic bearing control unit 201, information about the motor obtained from the motor drive control unit 202, and temperature information about a predetermined portion obtained from the TMS temperature measurement unit 203, and executes processing to protect the pump main body 100 (for example, automatically stopping the pump main body 100) if an abnormal state is detected. The protection function processing unit 204 also has a function of converting information about an abnormality in the pump main body 100 into data that can be processed by a user interface processing unit 209 (described later) and outputting the data to the user interface processing unit 209 if an abnormality has occurred in the pump main body 100.

[0045] The TMS output control unit 205 sends commands to an output device (hereinafter referred to as the "TMS output device"; in this embodiment, this corresponds to a relay that switches the power supply state of the heater and a valve connected to a water cooling pipe) for executing TMS control based on temperature information of a specified portion obtained from the TMS temperature measurement unit 203, and controls the ON / OFF of the TMS output device. Note that the TMS output control unit 205 corresponds to the "output control means" and "output control unit" in this specification.

[0046] The cumulative count interval measurement unit 206 counts, for example, the number of times the TMS output device is turned ON or OFF and measures the ON time or OFF time of the TMS output device based on information regarding the ON / OFF of the TMS output device obtained from the TMS output control unit 205 (information that the TMS output device has been turned ON or OFF).

[0047] The recording processing unit 207 converts the measurement values ​​relating to ON / OFF of the TMS output device obtained from the cumulative count interval measuring unit 206 (for example, the cumulative number of ON times (number of OFF times) of the TMS output device, the ON time (OFF time) of the TMS output device, and the average value thereof) into data recordable in the non-volatile memory 208 or data processable by the user interface processing unit 209, and outputs the data to these. The recording processing unit 207 also has a function of calling up data recorded in the non-volatile memory 208 and outputting it to the cumulative count interval measuring unit 206 and the user interface processing unit 209.

[0048] The non-volatile memory 208 periodically records data obtained from the recording processing unit 207. Specific examples of the non-volatile memory 208 include, for example, an EEPROM and an FeRAM. Note that, although the non-volatile memory 208 is used in this embodiment, other recording means including a volatile memory (SRAM or DRAM) may also be used.

[0049] The user interface processing unit 209 is connected to an information output unit 210 described later, and converts data obtained from the recording processing unit 207 and the protection function processing unit 204 into signals that can be output by the information output unit 210.

[0050] The information output unit 210 outputs information regarding ON / OFF of the TMS output device and information regarding an abnormality in the pump main body 100 based on a signal obtained from the user interface processing unit 209. The information output unit 210 may output information by displaying characters, images, etc., such as an LCD, or may output light (blink) such as an LED. The information output unit 210 is not limited to a device that allows the user to perceive the information visually, such as an LCD or an LED, but may be a device that can be perceived by other five senses (for example, a device that outputs sound and can be perceived by the user's hearing). The information output unit 210 may also be an external terminal that can perform communication by I / O signals or serial communication, for example, in order to provide information to the user via another device provided separately from the turbo molecular pump 10.

[0051] The above-mentioned information output unit 210 corresponds to the "information output means" in this specification.

[0052] Such a controller 200 allows the pump body 100 to operate normally, and in the event of an abnormality, the information output unit 210 can notify the user, and can also prompt the user to inspect and replace the temperature adjustment means at the appropriate time.

[0053] Here, the "accumulated count interval measurement" performed to inspect and replace the temperature adjustment means at an appropriate time will be described with reference to Fig. 3. The accumulated count interval measurement is mainly executed by the accumulated count interval measurement unit 206. First, in step 1, the accumulated count interval measurement unit 206 determines whether the current TMS output device is in the ON or OFF state based on information obtained from the TMS output control unit 205 that the TMS output device has been turned ON or OFF, and also determines whether the state of the TMS output device is the same as or different from the state when step 1 was previously executed (S1 in Fig. 3).

[0054] If the result of step 1 shows that the current state of the TMS output device is the same as the state when step 1 was executed the previous time (NO in S1 in Fig. 3), the current cumulative count interval measurement ends. Note that the cumulative count interval measurement is repeated at short intervals (e.g., 30 ms), and the next cumulative count interval measurement is executed immediately.

[0055] If the result of step 1 shows that the current state of the TMS output device is different from the state it was in the previous time step 1 was executed (YES in S1 in FIG. 3), in step 2, the cumulative count interval measurement unit 206 subtracts the time when the previous result of step 1 was YES from the current time to calculate the maintenance interval time during which the TMS output device maintained that state (S2 in FIG. 3).

[0056] To explain this in detail with reference to Fig. 4, for example, when the current time is T2 in Fig. 4, the TMS output device has changed from the ON state to the OFF state (YES in step 1), so step 2 is executed. Note that the time when YES was obtained in the previous step 1 (T1 in this explanation) is recorded in non-volatile memory 208. The cumulative count interval measurement unit 206 calls up the time T1 when YES was obtained in the previous step 1 from non-volatile memory 208 via the recording processing unit 207, and calculates the time between time T2 and time T1.

[0057] After executing step 2, the cumulative count interval measurement unit 206 executes step 3 of determining whether or not the current TMS output device is in the ON state (S3 in FIG. 3).

[0058] For example, if the current time is time T2 in Fig. 4, the TMS output device is in the OFF state, so the determination in step 3 is NO in S3 in Fig. 3, and the process proceeds to step 4 (S4 in Fig. 3). Note that the TMS output device is maintained in the ON state from time T1 to time T2. The cumulative count interval measurement unit 206 sets this time (the time T2-T1 calculated in step 2) as the "ON maintenance interval time."

[0059] In step 4, the cumulative count interval measurement unit 206 performs an averaging process on the calculated ON maintenance interval time of T2-T1. The averaging process here means averaging the currently calculated ON maintenance interval time of T2-T1 using past ON maintenance interval times. The averaging method is not particularly limited, but as an example, the most recent (n-1) ON maintenance interval times may be added to the ON maintenance interval time of T2-T1, and the sum of the ON maintenance interval times may be divided by n. The past ON maintenance interval times are recorded in the non-volatile memory 208, and in executing step 4, the cumulative count interval measurement unit 206 calls them from the non-volatile memory 208 via the recording processing unit 207.

[0060] After executing step 4, the cumulative count interval measurement unit 206 executes step 5 to update the previous information (information when YES was obtained in the previous step 1) recorded in the non-volatile memory 208 (S5 in FIG. 3). When the current time is T2 shown in FIG. 4 and the time when YES was obtained in the previous step 1 is T1, the cumulative count interval measurement unit 206 updates the time T1 to the time T2 as the previous information recorded in the non-volatile memory 208 via the recording processing unit 207, and also updates the state of the TMS output device at time T1 (ON state) to the state of the TMS output device at time T2 (OFF state). The cumulative count interval measurement unit 206 also records the ON maintenance interval time of T2-T1 before and after the averaging process in the non-volatile memory 208 via the recording processing unit 207. After executing step 5, the current cumulative count interval measurement ends.

[0061] On the other hand, if the current time determined as YES in step 1 is T3 in FIG. 4, cumulative count interval measurement section 206 does not proceed to step 4 described above, but executes steps 6 to 9 described below.

[0062] When the current time is T3 in FIG. 4, the TMS output device has changed from an OFF state to an ON state (YES in step 1), so step 2 is executed. Also in step 2, the time T2 for which YES was previously obtained in step 1 is called from the non-volatile memory 208 via the recording processing unit 207, and time T2 is subtracted from time T3 to calculate the time between them. Then, since the TMS output device is in the ON state at time T3, YES is determined in step 3, and the process proceeds to step 6. Note that the TMS output device is maintained in the OFF state from time T2 to time T3. The cumulative count interval measurement unit 206 sets this time (the time T3-T2 calculated in step 2) as the "OFF maintenance interval time".

[0063] In step 6, a process of counting up the cumulative number counter is executed (S6 in FIG. 3). Here, the "cumulative number counter" is information on the cumulative number of times the TMS output device has switched from an OFF state to an ON state, and is recorded in the non-volatile memory 208. The cumulative count interval measurement unit 206 counts up the cumulative number counter up to the previous time recorded in the non-volatile memory 208 via the recording processing unit 207 (adds 1 to the recorded cumulative number counter).

[0064] After executing step 6, the cumulative count interval measurement unit 206 executes step 7 in which it performs an averaging process on the calculated OFF maintenance interval time of T3-T2 (S7 in FIG. 3). The averaging process of the OFF maintenance interval time is also performed in the same manner as the ON maintenance interval time described above.

[0065] After executing step 7, the cumulative count interval measurement unit 206 executes step 8 (S8 in FIG. 3) of calculating the "period interval time" (T3-T1 in this case) shown in FIG. 4 by adding the calculated OFF maintenance interval time of T3-T2 and the ON maintenance interval time immediately before this OFF maintenance interval time (the ON maintenance interval time of T2-T1 in this case).

[0066] After executing step 8, the cumulative count interval measurement unit 206 executes step 9 in which it performs an averaging process on the calculated cycle interval time T3-T1 (S9 in FIG. 3). The averaging process of the cycle interval time is also performed in the same manner as the ON maintenance interval time and the like described above.

[0067] Then, in step 5, which is performed after step 8 is performed, the cumulative count interval measurement unit 206 updates the previous information recorded in the non-volatile memory 208 (S5 in FIG. 3). If the current time is T3 and the time when YES was selected in the previous step 1 is T2, the cumulative count interval measurement unit 206 updates the time T2 to the time T3 as the previous information recorded in the non-volatile memory 208, and also updates the state of the TMS output device at time T2 (OFF state) to the state of the TMS output device at time T3 (ON state). The cumulative count interval measurement unit 206 also records the OFF maintenance interval time of T3-T2 and the periodic interval time of T3-T1 before and after the averaging process in the non-volatile memory 208 via the recording processing unit 207. After step 5 is performed, the current cumulative count interval measurement is terminated.

[0068] By performing such cumulative count interval measurement, the non-volatile memory 208 records the cumulative number counter, which is the cumulative ON number of the TMS output device, as well as the ON maintenance interval time, OFF maintenance interval time, and cycle interval time before the averaging process, and the ON maintenance interval time, OFF maintenance interval time, and cycle interval time after the averaging process. Then, by outputting this information to the information output unit 210 via the user interface processing unit 209, the user can know the cumulative ON number of the TMS output device, etc. Therefore, the user can determine whether the cumulative ON number of the TMS output device exceeds the permitted ON number, for example, and can replace the TMS output device (for example, a relay or a valve) at an appropriate time. In this way, the TMS output device that has a high frequency of switching to the ON number and may lead to a breakdown can be replaced in advance, so that an unexpected stop of the vacuum pump can be prevented.

[0069] In this embodiment, the cumulative number of times the TMS output device is turned ON is measured. However, the TMS output device can also be replaced at an appropriate time by measuring the cumulative number of times it is turned OFF and outputting this information.

[0070] In addition, the ON maintenance interval time, OFF maintenance interval time, and cycle interval time averaged in the TMS output device tend to converge to a certain range if the exhausted device connected to the pump body 100 is operating stably, although there is some variation. In other words, when the ON maintenance interval time, OFF maintenance interval time, cycle interval time, etc. averaged show a steep change, the user can know that there is a possibility that a failure has occurred in the temperature adjustment means including the TMS output device (for example, if the cycle interval time of the valve connected to the water-cooled pipe changes significantly, in addition to the failure of the valve itself, there is a possibility that there has been a sudden change in the temperature of the cooling water, or the water-cooled pipe has been clogged due to foreign matter, etc.). In other words, even if the temperature measured by the temperature sensor disposed near a predetermined portion of the pump body 100 is within a predetermined range and no heating or cooling abnormality has actually occurred, it is possible to know that there is a possibility that an abnormality may occur in the future, and such heating or cooling abnormality can be prevented by performing appropriate inspections.

[0071] It is also possible to prevent such heating and cooling abnormalities based on the ON maintenance interval time, OFF maintenance interval time, and cycle interval time before the averaging process is performed, or based on the minimum and maximum values ​​of the ON maintenance interval time, OFF maintenance interval time, and cycle interval time.

[0072] Furthermore, such a method of predicting future malfunctions from the ON maintenance interval time, etc. is not limited to only the TMS output device, but can also be applied to other devices used in the pump main body 100. That is, even when the pump main body 100 is operated continuously or when the pump main body 100 is started and stopped periodically, the ON maintenance interval time, etc. of the device tends to converge within a certain range, so future malfunctions in the pump main body 100 can be prevented by performing appropriate inspections when the interval time exceeds this range.

[0073] Here, specific examples of the ON maintenance interval time, OFF maintenance interval time, and cycle interval time of the TMS output device will be described with reference to Fig. 5. In Fig. 5, ID1 indicates the relationship between time and temperature obtained from a temperature sensor attached near a part heated by TMS control. ID2 indicates the relationship between time and temperature obtained from a temperature sensor attached near a part cooled by TMS control. OD1 indicates the relationship between time and ON / OFF signal output from the TMS output control unit 205 to a relay connected to a heater that performs heating by TMS control. OD2 indicates the relationship between time and ON / OFF signal output from the TMS output control unit 205 to a valve connected to a cooling pipe that performs cooling by TMS control.

[0074] Figure 6 shows the results of executing the above-mentioned cumulative count interval measurement for the TMS control shown in Figure 5. Note that the times shown in Figure 6 are all times after averaging processing.

[0075] As shown in Figures 5 and 6, the ON maintenance interval time, OFF maintenance interval time, and cycle interval time of OD1 (relay) and OD2 (valve) are within a substantially constant range, although there is some variation. For this reason, it is determined that the likelihood of heating abnormalities or cooling abnormalities occurring in a predetermined portion of the pump body 100 is low. On the other hand, for example, if the ON maintenance interval time after averaging processing in OD1 (relay) falls outside a predetermined range (a range of 1 minute 45 seconds ± 20 seconds in the example shown in Figures 5 and 6), the user can predict that an abnormality may occur in the future, and can prevent heating abnormalities or cooling abnormalities by performing inspections as necessary.

[0076] The above-mentioned controller 200 outputs the cumulative count counter, ON maintenance interval time, etc. of the TMS output device recorded in the non-volatile memory 208 to the information output unit 210 to inform the user, but by configuring as shown in Figure 7, it is also possible to output a warning from the information output unit 210 when the cumulative count counter, ON maintenance interval time, etc. exceed a predetermined value.

[0077] In the configuration shown in FIG. 7, the record processing unit 207 has a function of converting the measurement value relating to the ON / OFF of the TMS output device obtained from the cumulative count interval measurement unit 206 into data that can be processed by the protection function processing unit 204.

[0078] The protection function processing unit 204 has a function of recording various threshold values ​​211, and compares the measurement values ​​regarding the ON / OFF of the TMS output device based on the data from the recording processing unit 207 with the threshold values ​​211, and outputs data indicating the comparison results to the user interface processing unit 209.

[0079] That is, for example, an allowable cumulative ON count in the TMS output device is recorded as the threshold value 211, and if the cumulative ON count of the TMS output device obtained from the recording processing unit 207 exceeds the allowable cumulative ON count, a warning is issued from the information output unit 210 to prompt replacement of the TMS output device (for example, a message indicating that the TMS output device should be replaced is displayed on the LCD), so that replacement of the TMS output device can be more reliably prompted. Also, for example, an allowable ON maintenance interval is stored as the threshold value 211, and if the ON maintenance interval of the TMS output device obtained from the recording processing unit 207 deviates from the threshold value 211, a warning is issued from the information output unit 210 to prompt inspection of the temperature adjustment means, so that heating abnormalities and cooling abnormalities in the pump body 100 can be prevented.

[0080] Although one embodiment of the present invention has been described above, the present invention is not limited to such a specific embodiment, and various modifications and changes are possible within the scope of the spirit of the present invention described in the claims unless otherwise specifically limited in the above description. Furthermore, the effects of the above embodiment are merely examples of the effects resulting from the present invention, and do not mean that the effects of the present invention are limited to the above effects. [Explanation of symbols]

[0081] 10: Turbo molecular pump (vacuum pump) 100: Pump body 200: Controller 205: TMS output control unit (output control means, output control unit) 206: Accumulation count interval measurement unit 207: Recording processing unit 208: Non-volatile memory 209: User interface processing unit 210: Information output unit (information output means)

Claims

1. A vacuum pump for exhausting gas from an evacuated device, comprising: a temperature adjusting means for adjusting a predetermined temperature of a predetermined portion of the vacuum pump; an output control means for operating the temperature adjustment means; an accumulative count interval measurement unit which calculates at least two of an ON maintenance interval time, an OFF maintenance interval time, and a cycle interval time which is the sum of the ON maintenance interval time and the OFF maintenance interval time of the temperature adjustment means based on information relating to the ON / OFF of the temperature adjustment means obtained from the output control means, and further calculates at least two of an averaged ON maintenance interval time of the temperature adjustment means, an averaged OFF maintenance interval time, and an averaged cycle interval time which is the sum of the ON maintenance interval time and the OFF maintenance interval time of the averaged process; a recording means for recording at least two of an ON-maintain interval time, an OFF-maintain interval time, and a cycle interval time of the temperature adjustment means obtained from the cumulative count interval measuring unit; an information output means for outputting at least two of the ON maintenance interval time on which the averaging process has been performed, the OFF maintenance interval time on which the averaging process has been performed, and the cycle interval time on which the averaging process has been performed, which are obtained from the cumulative count interval measurement unit; the cumulative count interval measurement unit calculates at least two of an ON maintenance interval time T2-T1 obtained by subtracting time T2 from time T2, an OFF maintenance interval time T3-T2 obtained by subtracting time T2 from time T3, and a periodic interval time T3-T1 obtained by subtracting time T1 from time T3, when the time T1 is the time when the temperature adjustment means changes from an ON state to an OFF state after time T1 and closest to time T1, and further an ON maintenance interval time obtained by adding the most recent (n-1) ON maintenance interval times recorded in the recording means to the ON maintenance interval time T2-T1, and dividing the sum of the ON maintenance interval times by n to obtain the averaged ON maintenance interval time; an OFF maintenance interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the OFF maintenance interval time T3-T2 and dividing the sum of the OFF maintenance interval times by n to obtain an averaged OFF maintenance interval time; and calculating at least two of the periodic interval times obtained by adding the most recent (n-1) periodic interval times recorded in the recording means to the periodic interval time T3-T1 and dividing the sum of the periodic interval times by n.

2. 2. The vacuum pump according to claim 1, wherein the information output means outputs information relating to the number of times the temperature adjustment means is turned on or off.

3. A controller for controlling a vacuum pump body that exhausts gas from an evacuated device, the vacuum pump body includes a temperature adjusting means for adjusting a predetermined portion of the vacuum pump body to a predetermined temperature; The controller: an output control unit that operates the temperature adjustment means; an accumulative count interval measurement unit that calculates at least two of an ON maintenance interval time, an OFF maintenance interval time, and a cycle interval time which is the sum of an ON maintenance interval time and an OFF maintenance interval time of the temperature adjustment means based on information related to ON / OFF of the temperature adjustment means obtained from the output control unit, and further calculates at least two of an averaged ON maintenance interval time of the temperature adjustment means, an averaged OFF maintenance interval time, and an averaged cycle interval time which is the sum of the ON maintenance interval time and the OFF maintenance interval time of the averaged process; a recording means for recording at least two of an ON-maintain interval time, an OFF-maintain interval time, and a cycle interval time of the temperature adjustment means obtained from the cumulative count interval measuring unit; an information output unit that outputs at least two of the ON maintenance interval time on which the averaging process is performed, the OFF maintenance interval time on which the averaging process is performed, and the cycle interval time on which the averaging process is performed, which are obtained from the cumulative count interval measurement unit, the cumulative count interval measurement unit calculates at least two of an ON maintenance interval time T2-T1 obtained by subtracting time T2 from time T2, an OFF maintenance interval time T3-T2 obtained by subtracting time T2 from time T3, and a periodic interval time T3-T1 obtained by subtracting time T1 from time T3, when the time T1 is the time when the temperature adjustment means changes from an ON state to an OFF state after time T1 and closest to time T1, and further an ON maintenance interval time obtained by adding the most recent (n-1) ON maintenance interval times recorded in the recording means to the ON maintenance interval time T2-T1, and dividing the sum of the ON maintenance interval times by n to obtain the averaged ON maintenance interval time; an OFF maintenance interval time obtained by adding the most recent (n-1) OFF maintenance interval times recorded in the recording means to the OFF maintenance interval time T3-T2 and dividing the sum of the OFF maintenance interval times by n to obtain an averaged OFF maintenance interval time; and a controller which adds the most recent (n-1) periodic interval times recorded in the recording means to the periodic interval time T3-T1, and divides the sum of the periodic interval times by n to calculate at least two of the periodic interval times subjected to the averaging process.

Images