Vacuum pump and controller

Abstract

The present invention proposes a vacuum pump and a controller for controlling the vacuum pump, which can check, replace, and prevent unexpected stoppage of a temperature adjustment mechanism at an appropriate time, and can reduce maintenance costs. The present invention is a vacuum pump (10) that discharges gas from an exhaust device, characterized by including a temperature adjustment mechanism for maintaining a predetermined temperature at a predetermined portion of the vacuum pump (10), an output control mechanism (205) for operating the temperature adjustment mechanism, and an information output mechanism (210) for outputting information related to opening / closing of the temperature adjustment mechanism from the output control mechanism (205).

Description

Technical Field

[0001] This invention relates to vacuum pumps and controllers. Background Technology

[0002] In the exhaust process within the vacuum chamber of semiconductor devices such as CVD equipment, vacuum pumps are generally used. In particular, turbomolecular pumps are often used due to their low residual gas content and ease of maintenance.

[0003] In the semiconductor manufacturing process, there are steps that involve applying various process gases to the semiconductor substrate. Turbomolecular pumps are used not only to create a vacuum inside the semiconductor device, but also to expel process gases from the device.

[0004] However, process gases are sometimes introduced into the chamber at high temperatures to enhance reactivity. In such cases, the temperature of the discharged process gas decreases while its pressure increases, causing it to sublimate from a gas into a solid and precipitate products. That is, the process gas sublimates inside the turbomolecular pump, and the solidified products adhere to the inside of the turbomolecular pump, gradually accumulating and narrowing the pump flow path, which can degrade the performance of the turbomolecular pump.

[0005] Previously, to address this problem, heaters or similar devices with relay-controlled switching were installed within turbomolecular pumps to heat areas where precipitates tend to accumulate to a predetermined temperature. At this point, if... Figure 8 (As shown in the system structure diagram of a conventional vacuum pump (turbomolecular pump), the temperature of the turbomolecular pump is measured by a TMS temperature metering unit connected to a TMS temperature sensor. The measured value is compared with a set temperature to control the output to the heater, etc. On the other hand, if the temperature of the turbomolecular pump rises due to heat diffusion from the heater, etc., it will affect the electronic circuit installed therein. In addition, as the temperature rises, the magnetic force of the permanent magnet used in the motor of the pump's rotating body decreases, and the electromagnet winding may break. Therefore, water-cooling pipes are arranged around them, and the flow of cooling water is controlled by valves, etc. (see, for example, Patent Document 1). Thus, conventional vacuum pumps include vacuum pumps equipped with temperature adjustment mechanisms (heater, relay, water-cooling pipes, valves, etc.) for maintaining a predetermined temperature in a predetermined part of the vacuum pump.

[0006] Patent document 1: Japanese Patent Application Publication No. 2003-148379.

[0007] However, such vacuum pumps previously relied on Figure 8The protection function processing unit, as indicated in the text, compares the measured value by the TMS temperature measurement unit with the allowable temperature to notify of abnormalities such as high temperature overheating / warning, abnormal temperature rise, abnormal low temperature, and open / short circuit. However, it does not consider the lifespan (number of opening / closing cycles, opening / closing time) of relays and valves, and there is a possibility that they may continue to be used until they malfunction. If relays or valves fail, the vacuum pump may abnormally become high or low temperature, resulting in the possibility of some malfunction causing the vacuum pump to suddenly stop.

[0008] If a vacuum pump stops operating, it could potentially affect the quality of semiconductors being manufactured. However, to prevent such unexpected vacuum pump stops, relays and valves are sometimes replaced periodically, regardless of the operating frequency. However, replacing relays and valves before they have reached the end of their lifespan increases maintenance costs. Summary of the Invention

[0009] In view of these aspects, the object of the present invention is to provide a vacuum pump and a controller for controlling the vacuum pump, which can inspect and replace the temperature adjustment mechanism used to set a predetermined part of the vacuum pump to a predetermined temperature at appropriate times, thereby preventing unexpected shutdowns and other occurrences, and further reducing maintenance costs.

[0010] The present invention is a vacuum pump for discharging gas from an exhaust device, characterized in that it comprises a temperature adjustment mechanism, an output control mechanism, and an information output mechanism. The aforementioned temperature adjustment mechanism is used to set a predetermined temperature at a predetermined position of the aforementioned vacuum pump. The aforementioned output control mechanism causes the aforementioned temperature adjustment mechanism to operate. The aforementioned information output mechanism outputs information related to the opening / closing of the aforementioned temperature adjustment mechanism obtained from the aforementioned output control mechanism.

[0011] Preferably, in such a vacuum pump, the aforementioned information output mechanism outputs information related to the number of times the temperature adjustment mechanism is turned on or off as information related to the opening / closing of the aforementioned temperature adjustment mechanism.

[0012] Here, the aforementioned information output mechanism can also output information related to the opening or closing time of the temperature adjustment mechanism as information related to the opening / closing of the aforementioned temperature adjustment mechanism.

[0013] Furthermore, the present invention is a controller for controlling a vacuum pump body that discharges gas from an exhaust device. The vacuum pump body is characterized by having a temperature adjustment mechanism for setting a predetermined temperature at a predetermined location of the vacuum pump body. The controller includes an output control unit and an information output unit. The output control unit activates the temperature adjustment mechanism, and the information output unit outputs information obtained from the output control unit related to the opening / closing of the temperature adjustment mechanism.

[0014] Invention Effects

[0015] According to the vacuum pump and controller of the present invention, the temperature adjustment mechanism can be checked and replaced at appropriate times based on information related to the opening / closing of the temperature adjustment mechanism output from the information output mechanism, thus preventing unexpected shutdown of the vacuum pump and reducing maintenance costs. Attached Figure Description

[0016] Figure 1 This is a schematic cross-sectional view of the vacuum pump body according to one embodiment of the present invention.

[0017] Figure 2 This is a system structure diagram of a vacuum pump according to one embodiment of the present invention.

[0018] Figure 3 This is a flowchart illustrating the operation of a vacuum pump according to one embodiment of the present invention.

[0019] Figure 4 It is a graph showing the on-up maintenance interval, the off-up maintenance interval, and the cycle interval.

[0020] Figure 5 It is a graph showing the relationship between the measured temperature and the time it takes for the temperature adjustment mechanism to open / close.

[0021] Figure 6 It means Figure 5 The table shows the on-up maintenance interval, off-up maintenance interval, and cycle interval of OD1 and OD2 (all averaged).

[0022] Figure 7 yes Figure 2 The system structure diagram shown in the figure is a variation.

[0023] Figure 8 This is a system structure diagram of a traditional vacuum pump (turbomolecular pump). Detailed Implementation

[0024] Hereinafter, an embodiment of the vacuum pump and controller of the present invention will be described with reference to the accompanying drawings. The vacuum pump in this embodiment is a turbomolecular pump 10, such as... Figure 1 , Figure 2 The pump shown consists of a pump body 100 and a controller (control device) 200. In this embodiment, the turbomolecular pump 10 connects the pump body 100 to an exhaust device (not shown) such as a semiconductor device, and discharges process gas from the cavity of the exhaust device under the control of the controller 20.

[0025] First, the pump body 100 will be described. The pump body 100 has a cylindrical outer cylinder 127, and an air intake 101 is provided at the upper end of the outer cylinder 127. A rotating body 103 is provided inside the outer cylinder 127, and the aforementioned rotating body 103 has multiple rotating blades 102a, 102b, 102c... for drawing and discharging process gas radially and in multiple layers around its periphery.

[0026] A rotor shaft 113 is mounted at the center of the rotating body 103. This rotor shaft 113 is suspended in the air and its position is controlled, for example by means of a so-called 5-axis controlled magnetic bearing.

[0027] In this embodiment, the upper radial electromagnet 104 consists of four electromagnets, which are arranged in pairs along the X and Y axes, which are mutually orthogonal coordinate axes that serve as the radial axis of the rotor shaft 113. Furthermore, an upper radial sensor 107, consisting of four electromagnets located close to these upper radial electromagnets 104, is provided at the pump body 100. The upper radial sensor 107 detects the radial displacement of the rotating body 103 and sends this information to the controller 200.

[0028] Here, the controller 200 controls the excitation of the upper radial electromagnet 104 via a compensation loop with PID regulation function based on the displacement signal detected by the upper radial sensor 107, thereby adjusting the upper radial position of the rotor shaft 113.

[0029] The rotor shaft 113 is formed, for example, of a material with high magnetic permeability (such as iron), and is attracted by the magnetic force of the upper radial electromagnet 104. The adjustment of the magnetic force is performed independently along the X-axis and Y-axis respectively.

[0030] Furthermore, the lower radial electromagnet 105 and the lower radial sensor 108 are configured in the same way as the upper radial electromagnet 104 and the upper radial sensor 107, so that the radial position of the lower side of the rotor shaft 113 is adjusted in the same way as the radial position of the upper side.

[0031] Furthermore, the axial electromagnets 106A and 106B are configured such that a circular metal disk 111 is disposed on the lower part of the rotor shaft 113, with the disks positioned vertically. The metal disk 111 is made of a material with high magnetic permeability, such as iron. An axial sensor 109 is provided to detect the axial displacement of the rotor shaft 113, and the axial displacement signal is sent to the controller 200.

[0032] Furthermore, the axial electromagnets 106A and 106B are energized and controlled by a compensation circuit with PID regulation function of controller 200 based on the axial displacement signal. The axial electromagnets 106A and 106B attract the metal disk 111 upward and downward respectively by means of magnetic force.

[0033] In this way, the controller 200 appropriately adjusts the magnetic force applied by the axial electromagnets 106A and 106B to the metal disk 111, so that the rotor shaft 113 is magnetically levitated in the axial direction and held in a non-contact manner in space.

[0034] The motor 121 has a plurality of magnetic poles arranged circumferentially around the rotor shaft 113. Each magnetic pole is controlled by the controller 200 to drive the rotor shaft 113 to rotate via an electromagnetic force acting between the rotor shaft 113 and the controller.

[0035] Multiple fixed wings 123a, 123b, 123c, etc. are arranged with a slight gap between them and the rotating blades 102a, 102b, 102c, etc. The rotating blades 102a, 102b, 102c, etc. are formed to be inclined at a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113 in order to respectively move the molecules of the discharged process gas downward through collision.

[0036] Furthermore, the fixed wings 123a, 123b, 123c... are also formed to be inclined at a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113, and are arranged alternately with the rotating wings 102a, 102b, 102c... on the inner side of the outer cylinder 127. Moreover, one end of the fixed wings 123a, 123b, 123c... is supported in a state where it is inserted between a plurality of stacked fixed wing spacers 125a, 125b, 125c...

[0037] Fixed wing spacers 125a, 125b, 125c... are ring-shaped components formed of metals such as aluminum, iron, stainless steel, copper, or alloys containing these metals as components.

[0038] An outer cylinder 127 is fixed to the outer periphery of the fixed wing spacers 125a, 125b, 125c, etc., with a slight gap between them. A base portion 129 is provided at the bottom of the outer cylinder 127, and a threaded spacer 131 is provided between the lower part of the fixed wing spacers 125a, 125b, 125c, etc. and the base portion 129. Furthermore, an exhaust port 133 is formed at the lower part of the threaded spacer 131 in the base portion 129, communicating with the outside.

[0039] The threaded spacer 131 is a cylindrical component made of metals such as aluminum, copper, stainless steel, iron, or alloys composed of these metals, with multiple helical threaded grooves 131a engraved on its inner circumferential surface. The direction of the helix of the threaded grooves 131a is the direction in which molecules of the process gas discharged in the direction of rotation of the rotating body 103 are moved toward the exhaust port 133.

[0040] At the lowest point, where the rotating wings 102a, 102b, 102c... of the rotating body 103 are continuous, the rotating wing 102d hangs down. The outer circumferential surface of the rotating wing 102d is cylindrical and extends toward the inner circumferential surface of the threaded spacer 131, approaching the inner circumferential surface of the threaded spacer 131 at a predetermined gap.

[0041] The base portion 129 is a disc-shaped component that forms the base of the turbomolecular pump 10, and is generally made of metals such as iron, aluminum, or stainless steel.

[0042] The base portion 129 physically holds the turbomolecular pump 10 and 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.

[0043] In the pump body 100 with such a structure, if the rotating blades 102a, 102b, 102c... are driven by the motor 121 and rotate together with the rotor shaft 113, then through the action of the rotating blades 102a, 102b, 102c... and the fixed blades 123a, 123b, 123c..., the process gas from the exhaust device is drawn through the intake port 101.

[0044] The process gas drawn in from the intake port 101 passes between the rotating blades 102a, 102b, 102c... and the fixed blades 123a, 123b, 123c... and is transferred to the base portion 129. At this time, due to the frictional heat generated when the process gas comes into contact or collides with the rotating blades 102a, 102b, 102c..., the conduction of heat generated by the motor 121, radiation, etc., the temperature of the rotating blades 102a, 102b, 102c... rises, but this heat is transferred to the fixed blades 123a, 123b, 123c... side due to radiation or conduction by the gas molecules of the process gas.

[0045] The fixed-wing spacers 125a, 125b, 125c... engage with each other at their outer periphery, transferring heat received by the fixed-wings 123a, 123b, 123c... from the rotating wings 102a, 102b, 102c... and frictional heat generated when the process gas contacts or collides with the fixed-wings 123a, 123b, 123c... to the outer cylinder 127 and the threaded spacer 131. Furthermore, the process gas transferred to the threaded spacer 131 is guided by the threaded groove 131a and directed to the exhaust port 133, where it is discharged from the pump body 100.

[0046] However, as described above, the temperature of the process gas decreases and the pressure increases, resulting in sublimation and solidification, thus precipitating products. At the pump body 100, there is a temperature variation around the exhaust port 133. In particular, the gaps near the rotating blade 102d and the threaded spacer 131 are narrow, making the flow path prone to narrowing due to the precipitated process gas products. Therefore, in the pump body 100 of this embodiment, for example, a heater, annular water-cooling pipe, and temperature sensor (e.g., a thermistor) are provided around the outer periphery of the base portion 129. Based on the signal from this temperature sensor, heating based on the heater and cooling based on the water-cooling pipe are controlled (hereinafter referred to as "TMS control"; TMS: Temperature Management System) to maintain the temperature of the base portion 129 at a temperature where products do not precipitate (set temperature). Here, if the set temperature under TMS control becomes too high, products are difficult to accumulate, so it is desirable to have a set temperature as high as possible.

[0047] On the other hand, if the temperature of the base section 129 increases, the temperature of the electronic circuit installed in the base section will also rise. Furthermore, if the temperature rises to a level beyond what is expected due to changes in the exhaust load, for example, it may exceed the allowable temperature of the semiconductor memory installed in the electronic circuit, causing maintenance information data such as control parameters, pump start-up time, and error history recorded in the memory to disappear. The loss of maintenance information data makes it impossible to determine when maintenance and inspection should be performed, leading to a major malfunction.

[0048] Furthermore, it is conceivable that if the temperature of the base portion 129 rises above a certain level, the current flowing to the electromagnet windings constituting the magnetic poles of the motor 121 increases, exceeding the allowable temperature of the windings. In such a case, there is a possibility that the electromagnet windings will break and the motor will stop.

[0049] Therefore, in the pump body 100, the heater, water cooling pipe, and parts designed to raise the temperature (e.g., near the rotor 102d and the threaded spacer 131) and parts designed to suppress the temperature (e.g., near the electronic circuit and the motor 121) are appropriately positioned. Furthermore, the controller 200 switches the opening / closing of relays that change the energization state of the heater and valves connected to the water cooling pipe at appropriate times, ensuring that a predetermined part of the pump body 100 is at a predetermined temperature. Additionally, the "temperature adjustment mechanism" mentioned in this specification corresponds to the heater, relay, water cooling pipe, valve, etc., described above in this embodiment.

[0050] Here, regarding controller 200, refer to... Figure 2 The following details will be provided. The controller 200 uses various electronic components or substrates on which they are mounted to achieve the functions described below.

[0051] The magnetic bearing control unit 201 controls the magnetic bearing of the pump body 100. Figure 1 The axial electromagnets 106A and 106B are controlled, and the motor drive control unit 202 controls the motor. Figure 1 (Control of motor 121). In addition, the TMS temperature metering unit 203 measures the temperature of a predetermined part of the pump body 100 based on the output signal from the temperature sensor (hereinafter referred to as "TMS temperature sensor") used to perform TMS control.

[0052] The aforementioned magnetic bearing control unit 201, motor drive control unit 202, TMS temperature measurement unit 203, and protection function processing unit 204 are connected. The protection function processing unit 204 monitors whether an abnormality occurs at the pump body 100 based on information related to the magnetic bearing obtained from the magnetic bearing control unit 201, information related to the motor obtained from the motor drive control unit 202, and temperature information at a predetermined location obtained from the TMS temperature measurement unit 203. If an abnormality occurs, it performs protection measures for the pump body 100 (e.g., automatically stopping the pump body 100). Furthermore, the protection function processing unit 204 also has the function of converting the information into processable data using the user interface processing unit 209 (described later) and outputting it to the user interface processing unit 209 when an abnormality occurs at the pump body 100.

[0053] Furthermore, the TMS output control unit 205, based on the temperature information of a predetermined location obtained from the TMS temperature measurement unit 203, sends commands to the output element (hereinafter referred to as "TMS output element"). This output element is equivalent to a relay that switches the energization state of the heater and a valve connected to the water cooling pipe in this embodiment. The TMS output control unit 205 is equivalent to the "output control mechanism" or "output control unit" as used in this specification.

[0054] The cumulative counting interval measurement unit 206 measures the on / off time of the TMS output element based on information related to the on / off state of the TMS output element (information on whether the TMS output element is turned on or off) obtained from the TMS output control unit 205, such as counting the number of times the TMS output element is turned on and off.

[0055] The recording processing unit 207 converts the measurement values ​​related to the on / off state of the TMS output element obtained from the cumulative counting interval measurement unit 206 (such as the cumulative number of times the TMS output element is turned on (number of times it is turned off), the on time (off time) of the TMS output element, and its average value) into data that can be recorded in the non-volatile memory 208 and processed by the user interface processing unit 209, and outputs them to them. The recording processing unit 207 also has the function of retrieving the data recorded in the non-volatile memory 208 and outputting it to the cumulative counting interval measurement unit 206 and the user interface processing unit 209.

[0056] The non-volatile memory 208 periodically records data obtained from the recording processing unit 207. Specific examples of the non-volatile memory 208 include EEPROM and FeRAM. However, while a non-volatile memory 208 is used in this embodiment, other recording mechanisms, such as volatile memory (SRAM, DRAM), may also be used.

[0057] The user interface processing unit 209 is connected to the information output unit 210, which will be described later, and converts the data obtained from the recording processing unit 207 and the protection function processing unit 204 into signals that can be output via the information output unit 210.

[0058] The information output unit 210 outputs information related to the on / off state of the TMS output element and information related to abnormalities of the pump body 100, based on signals received from the user interface processing unit 209. The information output unit 210 can output information by displaying text, images, etc., like an LCD, or by flashing light, like an LED. Furthermore, it is not limited to visual perception like an LCD or LED; it can also be perceived by other senses (e.g., by outputting sound and utilizing the user's hearing). In addition, the information output unit 210 can provide information to the user via other devices separately from the turbomolecular pump 10, such as external terminals for I / O signal-based communication or serial communication.

[0059] The aforementioned information output unit 210 is equivalent to the "information output mechanism" in this specification, etc.

[0060] With the help of such a controller 200, the normal operation of the pump body 100 can be performed, and the user can be notified from the information output unit 210 when an abnormality occurs. In addition, the temperature adjustment mechanism can be checked and replaced at the appropriate time.

[0061] Here, regarding the "cumulative counting interval measurement" performed to inspect and replace the temperature regulating mechanism at appropriate intervals, refer to... Figure 3The following explanation will be provided. The cumulative count interval measurement is primarily performed by the cumulative count interval measurement unit 206. First, as step 1, the cumulative count interval measurement unit 206, based on information obtained from the TMS output control unit 205 regarding whether the TMS output element is turned on or off, determines whether the current TMS output element is in an on or off state, and further determines whether the state is the same as or different from the state of the TMS output element during the last execution of step 1. Figure 3 S1).

[0062] The result of step 1 is the case where the current state of the TMS output element is the same as the state when step 1 was last executed. Figure 3 If S1 is not specified, the current cumulative count interval measurement ends. Alternatively, the cumulative count interval measurement is repeated over a short period (e.g., 30ms), and the next cumulative count interval measurement is executed immediately.

[0063] The result of step 1 is the case where the current state of the TMS output element differs from the state at the time of the last execution of step 1. Figure 3 In the case where S1 is "yes", as step 2, the cumulative counting interval measurement unit 206 subtracts the time in step 1 where "yes" was "yes" from the current time, and calculates the maintenance interval time for the TMS output element to maintain this state. Figure 3 (S2).

[0064] If referring to this point Figure 4 In addition, to provide specific details, for example, the current time is Figure 4 In the case of T2, the TMS output element changes from the on state to the off state (if it was true in step 1), so step 2 is executed. Furthermore, the time when it was true in the previous step 1 (T1 in this description) is recorded in the non-volatile memory 208. The cumulative counting interval measurement unit 206 retrieves the time T1 when it was true in the previous step 1 from the non-volatile memory 208 via the recording processing unit 207, and calculates the time interval by subtracting time T1 from time T2.

[0065] After executing step 2, the cumulative counting interval measurement unit 206 executes step 3, which determines whether the current TMS output element is in the on state. Figure 3 (S3).

[0066] For example, the current time point is Figure 4 At time T2, the TMS output element is in the off state, so the judgment in step 3 is... Figure 3 If no, proceed to step 4. Figure 3(S4). In addition, the TMS output element is kept in the on state between time T1 and time T2. The cumulative counting interval measurement unit 206 sets the time between these two times (the time T2-T1 calculated in step 2) as the "on-maintenance interval time".

[0067] In step 4, the cumulative counting interval measurement unit 206 performs an averaging process on the calculated on-endage interval time of T2-T1. This averaging process means averaging the currently calculated on-endage interval time of T2-T1 using past on-endage interval times. The averaging method is not particularly limited, but for example, the most recent (n-1) on-endage interval times relative to T2-T1 can be added together, and the total on-endage interval times can be divided by n. Furthermore, the past on-endage interval times are recorded in the non-volatile memory 208, and during step 4, the cumulative counting interval measurement unit 206 retrieves them from the non-volatile memory 208 via the recording processing unit 207.

[0068] After executing step 4, the cumulative counting interval measurement unit 206 executes step 5, which updates the previous information (the information from step 1) recorded in the non-volatile memory 208. Figure 3 (S5). The current time is Figure 4 If the time in step 1 was T1, as shown in the previous step, the cumulative counting interval measurement unit 206 updates time T1 to time T2 via the recording processing unit 207 as the previous information recorded in the non-volatile memory 208. Furthermore, it updates the state (on state) of the TMS output element at time T1 to the state (off state) of the TMS output element at time T2. Additionally, the cumulative counting interval measurement unit 206 records the on-state maintenance interval time between T2 and T1 before and after averaging processing in the non-volatile memory 208 via the recording processing unit 207. After executing step 5, the current cumulative counting interval measurement ends.

[0069] On the other hand, the current time that is determined to be yes in step 1 is Figure 4 In the case of T3, the cumulative counting interval measurement unit 206 does not proceed to step 4 as described above, but performs steps 6 to 9 as described below.

[0070] The current time is Figure 4In the case of T3, the TMS output element changes from the off state to the on state (which was true in step 1), so step 2 is executed. Furthermore, in step 2, the time T2, which was true in step 1, is retrieved from the non-volatile memory 208 via the recording processing unit 207, and the time interval is calculated by subtracting time T2 from time T3. Then, at time T3, the TMS output element is in the on state, so if it was determined to be true in step 3, step 6 is executed. Additionally, the TMS output element is kept in the off state between time T2 and time T3. The cumulative counting interval measurement unit 206 sets the time interval (the time T3-T2 calculated in step 2) as the "off maintenance interval time".

[0071] In step 6, the cumulative count is incremented by one. Figure 3 (S6). Here, "cumulative count" refers to information related to the cumulative number of times the TMS output element switches from the off state to the on state, which is recorded in the non-volatile memory 208. The cumulative count interval measurement unit 206 increments the cumulative count recorded in the non-volatile memory 208 up to the last time by one (adding 1 to the recorded cumulative count).

[0072] After executing step 6, the cumulative counting interval measurement unit 206 performs step 7, which involves averaging the calculated shutdown maintenance interval time of T3-T2. Figure 3 (S7). The averaging process for the shutdown maintenance interval is also performed in the same way as the previously described startup maintenance interval.

[0073] After executing step 7, the cumulative counting interval measurement unit 206 adds the calculated shutdown maintenance interval time of T3-T2 to the previous opening maintenance interval time (this time the opening maintenance interval time of T2-T1), and performs the calculation. Figure 4 Step 8 of the "period interval time" shown (this time T3-T1) Figure 3 (S8).

[0074] After executing step 8, the cumulative counting interval measurement unit 206 performs step 9, which involves averaging the calculated period interval time between T3 and T1. Figure 3 (S9). The averaging process for the period interval time is also performed in the same way as the previously described start-up maintenance interval time, etc.

[0075] Furthermore, in step 5, which is performed after step 8, the cumulative counting interval measurement unit 206 records the last information update in the non-volatile memory 208. Figure 3(S5). If the current time is T3 and the previous time in step 1 was T2, the cumulative counting interval measurement unit 206 updates time T2 to time T3 as the previous information recorded in the non-volatile memory 208. Furthermore, it updates the state of the TMS output element (off state) at time T2 to the state of the TMS output element (on state) at time T3. In addition, the cumulative counting interval measurement unit 206 records the off-duty maintenance interval time from T3 to T2 and the cycle interval time from T3 to T1 before and after averaging processing in the non-volatile memory 208 via the recording processing unit 207. After executing step 5, this cumulative counting interval measurement ends.

[0076] By performing such cumulative counting interval measurement, the non-volatile memory 208 records, in addition to the cumulative number of times the TMS output element is turned on (i.e., the cumulative count), the on-time maintenance interval, the off-time maintenance interval, and the cycle interval before averaging, and after averaging. Furthermore, this information is output to the information output unit 210 via the user interface processing unit 209, thereby allowing the user to know the cumulative number of times the TMS output element is turned on. Therefore, the user can determine, for example, whether the cumulative number of times the TMS output element is turned on exceeds the allowed number of turns, and can replace the TMS output element (e.g., a relay, valve) at an appropriate time. In this way, TMS output elements that frequently switch between on-time and off-time and are prone to failure can be replaced in advance, thus preventing unexpected shutdowns of the vacuum pump.

[0077] In addition, in this embodiment, the cumulative number of times the TMS output element is turned on is measured, but by measuring the cumulative number of times it is turned off and outputting this information, the TMS output element can also be replaced at an appropriate time.

[0078] Furthermore, while the on-state interval, off-state interval, and cycle interval of the TMS output element averaging process may be slightly uneven, they tend to converge to a constant range if the exhaust device connected to the pump body 100 operates stably. That is, if there are abrupt changes in the on-state interval, off-state interval, and cycle interval of the averaging process, the user can be aware of the possibility of a malfunction in the temperature adjustment mechanism, including the TMS output element (for example, if the cycle interval of the valve connected to the water-cooling pipe changes significantly, in addition to valve malfunction, there is a possibility of abrupt temperature changes in the cooling water, blockage of the water-cooling pipe due to foreign objects, etc.). In other words, by using a temperature sensor located near a predetermined location on the pump body 100, the temperature measured converges to a predetermined range, allowing for the identification of situations where abnormal heating or cooling may occur even if no actual abnormalities occur. Therefore, appropriate checks can be performed, thereby preventing such abnormalities.

[0079] Furthermore, prevention of such heating and cooling anomalies can be based on the on-state maintenance interval, off-state maintenance interval, and cycle interval before averaging. Alternatively, it can be based on the minimum and maximum values ​​of the on-state maintenance interval, off-state maintenance interval, and cycle interval.

[0080] Furthermore, the method of predicting future malfunctions based on such start-up and maintenance intervals is not limited to TMS output components, but can also be applied to other components used in the pump body 100. That is, when the pump body 100 operates continuously, or when the pump body 100 is periodically started and stopped, the start-up and maintenance intervals of components tend to converge to a certain constant range. Therefore, if they exceed this range, appropriate inspections can be performed, thereby preventing future malfunctions of the pump body 100.

[0081] For specific examples regarding the on-up sustain interval, off sustain interval, and cycle interval of the TMS output element, please refer to [link / reference]. Figure 5 At the same time, an explanation will be provided. Figure 5 ID1 represents the relationship between temperature and time obtained from a temperature sensor installed near the part heated by TMS control. ID2 represents the relationship between temperature and time obtained from a temperature sensor installed near the part cooled by TMS control. OD1 represents the relationship between the on / off signal output from the TMS output control unit 205 and time, relative to the relay connected to the heater heated by TMS control. OD2 represents the relationship between the on / off signal output from the TMS output control unit 205 and time, relative to the valve connected to the cooling pipe cooled by TMS control.

[0082] and, Figure 6 Relative to Figure 5 The TMS control shown executes the aforementioned cumulative counting interval measurement results. Additionally, Figure 6 The times shown are all averaged.

[0083] like Figure 5 , Figure 6 As shown, the opening and closing intervals, and cycle intervals of OD1 (relay) and OD2 (valve) are slightly uneven but remain within a generally constant range. Therefore, the probability of an abnormal heating or cooling at a predetermined location in the pump body 100 is low. On the other hand, for example, if the opening and closing intervals of OD1 (relay) are averaged, the probability of an abnormal heating or cooling at a predetermined location in the pump body 100 is low. Figure 5 , Figure 6 In the example shown, the deviation is within the range of 1 minute 45 seconds ± 20 seconds. If the deviation is too large, the user can anticipate the possibility of future abnormalities. Therefore, by conducting appropriate checks, abnormal heating and cooling can be prevented.

[0084] The aforementioned controller 200 transmits information to the user by outputting the accumulated count of the TMS output element and the on / off maintenance interval, etc., recorded in the non-volatile memory 208 to the information output unit 210. However, it can also transmit information via methods such as... Figure 7 When the cumulative count or the start-up maintenance interval exceeds a predetermined value, a warning is output from the information output unit 210.

[0085] Figure 7 In the structure shown, the recording processing unit 207 has the following function: converting the measurement values ​​related to the on / off state of the TMS output element obtained from the cumulative counting interval measurement unit 206 into data that can be processed by the protection function processing unit 204.

[0086] Furthermore, the protection function processing unit 204 has the function of recording various thresholds 211, and compares the measurement value related to the on / off state of the TMS output element with the threshold 211 based on the data from the recording processing unit 207, and outputs the data representing the comparison result to the user interface processing unit 209.

[0087] That is, as a threshold 211, for example, the allowable cumulative number of times the TMS output element can be turned on is pre-recorded. If the cumulative number of times the TMS output element can be turned on, as obtained from the recording processing unit 207, exceeds the allowable cumulative number of times, a warning urging the replacement of the TMS output element can be issued from the information output unit 210 (for example, displaying on the LCD that the TMS output element should be replaced), so that the replacement of the TMS output element can be more effectively urged. In addition, as a threshold 211, for example, an allowable on-state duration can be pre-stored. If the on-state duration of the TMS output element obtained from the recording processing unit 207 deviates from the threshold 211, a warning urging the temperature adjustment mechanism to be checked can be issued from the information output unit 210, so that abnormal heating or cooling of the pump body 100 can be prevented.

[0088] The present invention has been described above according to one embodiment, but the present invention is not limited to this specific embodiment. Various modifications and alterations can be made within the scope of the spirit of the present invention as set forth in the claims, unless otherwise specified in the above description. Furthermore, the effects of the above embodiment are merely illustrative of the effects produced by the present invention and do not imply that the effects of the present invention are limited to the effects described above.

[0089] Explanation of reference numerals in the attached figures

[0090] 10: Turbomolecular pump (vacuum pump)

[0091] 100: Pump body

[0092] 200: Controller

[0093] 205: TMS Output Control Unit (Output Control Mechanism, Output Control Section)

[0094] 206: Cumulative Counting Interval Measurement Department

[0095] 207: Records Processing Department

[0096] 208: Non-volatile memory

[0097] 209: User Interface Processing Department

[0098] 210: Information Output Department (Information Output Organization).

Claims

1. A vacuum pump for discharging gas from an exhaust device, characterized in that, have: A temperature adjustment mechanism is used to maintain a predetermined temperature at a predetermined location of the aforementioned vacuum pump; The output control mechanism causes the aforementioned temperature adjustment mechanism to operate. The cumulative counting interval metering unit calculates the on / off interval time, the off interval time, and the periodic interval time, which is the sum of the on / off interval time and the off interval time, based on the information related to the on / off of the temperature adjustment mechanism obtained from the output control mechanism. It then calculates the averaged on / off interval time, the averaged off interval time, and the averaged periodic interval time, which is the sum of the averaged on / off interval time and the averaged off interval time. The recording mechanism records the opening and closing interval time, and the cycle interval time of the aforementioned temperature adjustment mechanism obtained from the aforementioned cumulative counting interval metering unit. The information output mechanism outputs the on-state maintenance interval time, the off-state maintenance interval time, and the cycle interval time, all of which have undergone the aforementioned averaging process, obtained from the aforementioned cumulative counting interval metering unit. The aforementioned cumulative counting interval measurement unit calculates the following: Let T1 be the time when the temperature adjustment mechanism changes from the closed state to the open state; let T2 be the time when the temperature adjustment mechanism changes from the open state to the closed state closest to T1 after T1; and let T3 be the time when the temperature adjustment mechanism changes from the closed state to the open state closest to T2 after T2. Then, it calculates the open maintenance interval time (T2-T1) minus time T2, the closed maintenance interval time (T3-T2) minus time T3, and the periodic interval time (T3-T1) minus time T3. Furthermore, calculate The aforementioned opening and holding interval time for T2-T1 is recorded by adding the most recent n-1 opening and holding interval times recorded by the aforementioned recording mechanism, and then dividing the total opening and holding interval time by n to obtain the aforementioned averaged opening and holding interval time. The aforementioned shutdown maintenance intervals for T3-T2 are recorded by adding the most recent n-1 shutdown maintenance intervals recorded by the aforementioned recording mechanism, and then dividing the total shutdown maintenance intervals by n to obtain the aforementioned averaged shutdown maintenance intervals. The period interval time of T3-T1 is the period interval time that has been averaged by adding the most recent n-1 period interval times recorded by the aforementioned recording mechanism and dividing the total period interval time by n.

2. The vacuum pump as described in claim 1, characterized in that, The aforementioned information output mechanism outputs information related to the number of times the temperature adjustment mechanism is turned on or off as information related to the opening / closing of the aforementioned temperature adjustment mechanism.

3. A controller for controlling the body of a vacuum pump that discharges gas from an exhaust device, characterized in that, The aforementioned vacuum pump body is equipped with a temperature adjustment mechanism for maintaining a predetermined temperature at a predetermined location within the vacuum pump body. The aforementioned controller has: The output control unit activates the aforementioned temperature adjustment mechanism. The cumulative counting interval measurement unit calculates the on / off interval time, the off interval time, and the periodic interval time, which is the sum of the on / off interval time and the off interval time, based on the information related to the on / off of the temperature adjustment mechanism obtained from the output control unit. It then calculates the averaged on / off interval time, the averaged off interval time, and the averaged periodic interval time, which is the sum of the averaged on / off interval time and the averaged off interval time. The recording mechanism records the opening and closing interval time, and the cycle interval time of the aforementioned temperature adjustment mechanism obtained from the aforementioned cumulative counting interval metering unit. The information output unit outputs the on-state maintenance interval time, the off-state maintenance interval time, and the cycle interval time, all of which have undergone the aforementioned averaging process, obtained from the aforementioned cumulative counting interval measurement unit. The aforementioned cumulative counting interval measurement unit calculates the following: Let T1 be the time when the temperature adjustment mechanism changes from the closed state to the open state; let T2 be the time when the temperature adjustment mechanism changes from the open state to the closed state closest to T1 after T1; and let T3 be the time when the temperature adjustment mechanism changes from the closed state to the open state closest to T2 after T2. Then, it calculates the open maintenance interval time (T2-T1) minus time T2, the closed maintenance interval time (T3-T2) minus time T3, and the periodic interval time (T3-T1) minus time T3. Furthermore, calculate The aforementioned opening and holding interval time for T2-T1 is recorded by adding the most recent n-1 opening and holding interval times recorded by the aforementioned recording mechanism, and then dividing the total opening and holding interval time by n to obtain the aforementioned averaged opening and holding interval time. The aforementioned shutdown maintenance intervals for T3-T2 are recorded by adding the most recent n-1 shutdown maintenance intervals recorded by the aforementioned recording mechanism, and then dividing the total shutdown maintenance intervals by n to obtain the aforementioned averaged shutdown maintenance intervals. The period interval time of T3-T1 is the period interval time that has been averaged by adding the most recent n-1 period interval times recorded by the aforementioned recording mechanism and dividing the total period interval time by n.

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