Vacuum pump system and interface circuit

Abstract

[Problem] Provided is a vacuum pump system and an interface circuit in which one interface circuit can monitor and control a plurality of vacuum pumps when the plurality of vacuum pumps are monitored and controlled from a customer supervisory control tool via the interface circuit [Solving Means] Turbomolecular pumps 100 and control devices 300 are provided in pairs. An interface circuit 23 and AC / DC power supply circuits 15A, 15B, and 15C are not included in the control devices 300 but are configured in a separate integration unit 400. Conventional interface circuits 13A, 13B, and 13C are provided for respective turbomolecular pumps 100 in order to monitor and control respective control devices 200A, 200B, and 200C. In contrast, the interface circuit 23 integrally monitor and control the control devices 300A, 300B, and 300C. Thus, one interface circuit 23 is configured for three turbomolecular pumps 100.

Description

VACUUM PUMP SYSTEM AND INTERFACE CIRCUIT

[0001] The present invention relates to a vacuum pump system and an interface circuit, and in particular to a vacuum pump system and an 5 interface circuit in which one interface circuit can monitor and control a plurality of vacuum pumps when the plurality of vacuum pumps are monitored and controlled from a customer supervisory control tool via the interface circuit.

[0002] With the recent development of electronics, the demand for 10 semiconductors, such as memories and integrated circuits, is rapidly increasing. These semiconductors are manufactured by doping extremely pure semiconductor substrates with impurities to impart electrical properties and etching fine circuits onto semiconductor substrate, for example. 15

[0003] The aforementioned work needs to be performed in a chamber under high vacuum conditions to avoid effects of dust or the like in the air. A vacuum pump is commonly used for exhaust of this chamber. Particularly, a turbomolecular pump, which is a type of vacuum pump, is often used from the viewpoints of low residual gas content and ease of 20 maintenance. The semiconductor manufacturing process includes many steps of causing various process gases to act on semiconductor substrates, and the turbomolecular pump is used not only to produce a vacuum in the chamber but also to exhaust the process gases from the chamber. 25

[0004] Fig. 11 shows a configuration diagram of a conventional vacuum pump system for monitoring and controlling a plurality of turbomolecular pumps from a customer supervisory control tool. In Fig. 11, conventionally, a communication interface cable 3A conforming to RS232, RS485, EtherCAT, Profibus, or the like is connected between a customer 30 supervisory control tool 1 and a control device 200A. Fig. 11 shows a case where the control device 200A is connected to a turbomolecular pump 100A, but they may be separated from each other.

[0005] The control device 200A includes a motor control circuit 5A for driving a motor in the turbomolecular pump 100A, a magnetic bearing 35 control circuit 7A for controlling a magnetic bearing device, a TMS control circuit 9A for preventing accumulation of deposits deriving from a process gas, a supervisor circuit 11A for detecting abnormalities in pump status, an interface circuit 13A, and an AC / DC power supply circuit15A. The interface circuit 13A serves to transmit operation commands and information acquisition commands from the customer supervisory control tool 1 to the aforementioned circuits in the control device 200A, and transmit information acquired from the circuits in the control device 5 200A to the customer supervisory control tool 1. The AC / DC power supply circuit 15A is provided to supply electric power to the circuits in the control device 200A (e.g. see PTL 1).

[0006] [PTL 1] Japanese Patent Application Publication No. 2001-349295 10 [Summary of the Invention]

[0007] The circuits in the control device 200A are similarly provided in a control device 200B that is connected to a turbomolecular pump 100B, and a control device 200C that is connected to a turbomolecular pump 100C. The control devices 200B and 200C are directly connected to the 15 customer supervisory control tool 1 via respective communication interface cables 3B and 3C. That is, the customer supervisory control tool 1 is connected to the same number of control devices as the number of turbomolecular pumps 100. This required a large number of cables to be installed as well as 20 time and labor for laying out the cables, and is thus troublesome. Moreover, the same types of circuits are built in the respective control devices, increasing the required size of the control devices and the cost.

[0008] The present invention has been made in view of the foregoing 25 problem, and an object is to provide a vacuum pump system and an interface circuit in which one interface circuit can monitor and control a plurality of vacuum pumps when the plurality of vacuum pumps are monitored and controlled from a customer supervisory control tool via the interface circuit. 30

[0009] The present invention (Claim 1) is a vacuum pump system including: a plurality of vacuum pumps; and a plurality of control devices configured to control the plurality of vacuum pumps in one-to-one correspondence; and an interface circuit disposed independently of the plurality of control devices and including: an operation processor 35 configured to integrate communication of an operation signal and an acquired information signal with the plurality of control devices and to control each of the control devices; and an information acquisition processor configured to acquire information from the plurality of controldevices.

[0010] Communication of the operation signal and the acquired information signal with the plurality of control devices is integrated, thereby reducing the cost and the necessary space compared to a 5 conventional case in which a plurality of pumps requires the same number of interface circuits. Further, communication wiring is simplified, and time and labor for communication wiring is thus simplified. One interface circuit can monitor and control of the plurality of vacuum pumps. Thus, the number of interface circuits required is smaller 10 than the number of vacuum pumps.

[0011] The present invention (Claim 2) is an invention of a vacuum pump system, wherein the interface circuit further includes: an input- output means for monitoring and controlling the plurality of control device; and a signal analysis means for receiving, from the input-output 15 means, a signal including: a pump position for identifying one of the plurality of vacuum pumps; and a command being an operation command or an information acquisition command, and analyzing the signal, if a result of the signal analysis means analyzing the signal indicates that the command included in the signal is the operation command, the command is passed to 20 the operation processor, and if a result of the signal analysis means analyzing the signal indicates that the command included in the signal is the information acquisition command, the command is passed to the information acquisition processor.

[0012] The pump position and the operation or information acquisition 25 command are combined to generate one command on the supervisory control tool side. The pump position is an identifier for identifying one of the plurality of vacuum pumps. The operation command includes content of an operation to the identified vacuum pump. The information acquisition command includes information to be acquired from the identified vacuum 30 pump. The signal analysis means of the interface circuit analyzes the command and separates the command into an operation command and an information acquisition command based on a result of the analysis. The operation command is processed by the operation processor, and the 35 information acquisition command is processed by the information acquisition processor. The thus-configured data covers the plurality of vacuum pumps and includes a plurality of information types such as the number of rotationsand a motor current and data pertaining to these information types, but can be stored as one integrated piece of information in a storage means. The storage means thus requires only a small storage area. Furthermore, compared to a conventional case in which a storage means is provided for 5 an interface circuit of each vacuum pump, the present embodiment requires only one storage means, which is space-saving. The vacuum pump system can thus be configured inexpensively.

[0013] Further, the present invention (Claim 3) is an invention of a vacuum pump system, wherein the vacuum pump system further includes a 10 power supply portion configured to supply electric power to the plurality of control devices, the power supply portion being integrated with the interface circuit into an integration unit and disposed independently of the plurality of control devices.

[0014] The power supply portion and the interface circuit are 15 integrated as an integration unit, which is space-saving.

[0015] Further, the present invention (Claim 4) is an invention of a vacuum pump system, wherein the information acquisition processor includes an all-pump information collector configured to regularly acquire information regarding the plurality of vacuum pumps and hold the 20 acquired information, and when the command included in the signal is received, necessary information is extracted from the all-pump information collector based on the pump position and the acquired information type that are obtained by analyzing the command, and the input-output means outputs the extracted information to an external 25 device.

[0016] Information acquired by the all-pump information collector can constantly be kept up-to-date by regularly acquiring information regarding the plurality of vacuum pumps. This makes it possible, when a command is received, to quickly extract necessary information in 30 accordance with content of the command.

[0017] Further, the present invention (Claim 5) is an invention of a vacuum pump system, wherein when the command included in the signal is received, the information acquisition processor sequentially acquires information from the plurality of control devices based on the pump 35 position and the acquired information type that are obtained by analyzing the command, and the input-output means outputs the acquired information to an external device.

[0018] When a command is received, information is sequentiallyextracted from the control device based on the pump position and the acquired information type obtained by analyzing the command. This eliminates the need to prepare a large-capacity storage means.

[0019] Further, the present invention (Claim 6) is an invention of a 5 vacuum pump system, wherein the vacuum pump system further includes a supervisor module configured to monitor information acquired by the information acquisition processor, and if an abnormality is found, stop a corresponding pump out of the plurality of vacuum pump.

[0020] The supervisor module monitoring information acquired by the 10 information acquisition processor enables quick detection of abnormalities, thus ensuring safe operation.

[0021] Further, the present invention (Claim 7) is an invention of a vacuum pump system, wherein one common communication standard is used as a communication standard between the interface circuit and the plurality 15 of control devices.

[0022] By using one common communication standard for transmission from the interface circuit to the plurality of control devices, only one type of distribution cable and one type of receiving function installed in the plurality of the control devices are required, thereby reducing 20 the cost.

[0023] Further, the present invention (Claim 8) is an invention of a vacuum pump system, wherein the vacuum pump system further includes: a key input reader configured to read a signal of key input and pass an input signal to the operation processor to perform an operation indicated 25 by the key input; and a display data output module configured to display a signal extracted by the information acquisition processor, wherein the key input reader and the display data output module are attached to the integration unit.

[0024] Attaching the key input reader and the display data output 30 module to the unit allows work to be performed efficiently at sites closer to the vacuum pumps.

[0025] Further, the present invention (Claim 9) is an invention of an interface circuit, and is an interface circuit to be mounted in a vacuum pump system that includes: a plurality of vacuum pumps; and a plurality 35 of control devices configured to control the plurality of vacuum pumps in one-to-one correspondence, the interface circuit disposed independently of the plurality of control devices and including: an operation processor configured to integrate communication of an operation signal and anacquired information signal with the plurality of control devices and to control each of the control devices; and an information acquisition processor configured to acquire information from the plurality of control devices. 5

[0026] Further, the present invention (Claim 10) is an invention of an interface circuit, wherein the interface circuit is integrated with a power supply portion configured to supply electric power to the plurality of control devices, and is disposed independently of the plurality of control devices. 10

[0027] Further, the present invention (Claim 11) is an invention of an interface circuit, wherein the interface circuit further includes a supervisor module configured to monitor information acquired by the information acquisition processor, and if an abnormality is found, stop a corresponding pump out of the plurality of vacuum pump. 15

[0028] As described above, according to the present invention (Claim 1), an interface circuit is disposed independently of the plurality of control devices and includes: an operation processor configured to integrate communication of an operation signal and an acquired information signal with the plurality of control devices and to control 20 each of the control devices; and an information acquisition processor configured to acquire information from the plurality of control devices. This configuration reduces the cost and saves space compared to a conventional case where the same number of interface circuits as the number of pumps is necessary. Further, communication wiring is 25 simplified, and time and labor for communication wiring is thus simplified.

[0029] [Fig. 1] Fig. 1 is an overall configuration diagram of a vacuum pump system 30 according to an embodiment of the present invention. [Fig. 2] Fig. 2 is a configuration diagram of a turbomolecular pump. [Fig. 3] Fig. 3 is a block diagram of an interface circuit (a method of acquiring 35 pump information in advance). [Fig. 4] Fig. 4 is a configuration diagram of a communication frame. [Fig. 5]Fig. 5 shows an example of data stored in a storage device of an all-pump information collector. [Fig. 6] Fig. 6 is a block diagram of the interface circuit (a method of 5 sequentially collecting pump information). [Fig. 7] Fig. 7 is an overall configuration diagram of the vacuum pump system in which a supervisor circuit is accommodated together with the interface circuit in an integration unit. 10 [Fig. 8] Fig. 8 is a block diagram of the interface circuit that includes the supervisor circuit. [Fig. 9] Fig. 9 is an overall configuration diagram of the vacuum pump system that 15 includes an input device and a display device. [Fig. 10] Fig. 10 is a block diagram of the interface circuit that is provided with the input device and the display device. [Fig. 11] 20 Fig. 11 is a configuration diagram of a conventional vacuum pump system. [Description of Drawings]

[0030] Hereinafter, an embodiment of the present invention will be described. Fig. 1 is an overall configuration diagram of a vacuum pump system, which is the embodiment of the present invention, and Fig. 2 is a 25 configuration diagram of a turbomolecular pump. Although Fig. 1 shows control devices 300 integrated with turbomolecular pumps 100, the present embodiment can also be applied even if the turbomolecular pumps 100 are separate from the control devices 300. 30

[0031] A motor control circuit 5, a magnetic bearing control circuit 7, a TMS control circuit 9, and a supervisor circuit 11 accommodated in each control device 300 as shown in Fig. 1 are necessary for drive control of a corresponding turbomolecular pump 100, and are configured and adjusted for each pump. 35 The turbomolecular pumps 100 and the control devices 300 are provided in pairs. Thus, control devices 300A, 300B, and 300C are attached to respective turbomolecular pumps 100A, 100B, and 100C. Meanwhile, an interface circuit 23 and AC / DC power supply circuits 15A,15B, and 15C are not included in the control devices 300 but are configured in a separate integration unit 400.

[0032] Conventional interface circuits 13A, 13B, and 13C are provided for respective turbomolecular pumps 100 in order to monitor and control 5 respective control devices 200A, 200B, and 200C. In contrast, one interface circuit 23 is configured to integrally monitor and control the control devices 300A, 300B, and 300C. Thus, in Fig. 1, one interface circuit 23 is configured for three turbomolecular pumps 100. However, the number of turbomolecular pumps 100 10 is not limited to three. The turbomolecular pumps 100 may be divided into groups each having a plurality of turbomolecular pumps, and the interface circuit 23 may be provided in the integration unit 400 in correspondence with each group.

[0033] The AC / DC power supply circuits 15A, 15B, and 15C are 15 collectively configured in the integration unit 400. Note that a cable between the AC / DC power supply circuit 15A and the control device 300A and a cable between the interface circuit 23 and the control device 300A can be combined into one cable. The same applies to a cable between the AC / DC power supply circuit 15B and the control device 300B, a cable 20 between the interface circuit 23 and the control device 300B, a cable between the AC / DC power supply circuit 15C and the control device 300C, and a cable between the interface circuit 23 and the control device 300C. The interface circuit is configured to integrally manage a plurality of pumps, and a power supply circuit section and the interface circuit 25 are combined into a unit, which is space-saving. Although a plurality of communication interface cables 3 are laid between the conventional customer supervisory control tool 1 and the control devices 200 as shown in Fig. 11, the present embodiment uses only one cable, thus simplifying cable wiring as well. 30

[0034] In Fig. 2, the turbomolecular pump 100 has an inlet port 101 formed at an upper end of a cylindrical outer tube 127. The outer tube 127 contains a rotating body 103 that has a plurality of rotor blades 102 (102a, 102b, 102c, ...), which are turbine blades for sucking and exhausting gas, arranged radially and in multiple stages on a 35 circumferential portion of the rotating body 103. A rotor shaft 113 is attached at the center of the rotating body 103, and is supported in the air and subjected to position control by, for example, a five-axis controlled magnetic bearing. The rotating body 103 is commonly made ofmetal such as aluminum or an aluminum alloy.

[0035] Upper radial electromagnets 104 include four electromagnets arranged in pairs on X and Y axes. Four upper radial sensors 107 are provided close to the upper radial electromagnets 104 and in 5 correspondence with the respective upper radial electromagnets 104. The upper radial sensors 107 are, for example, inductance sensors or eddy current sensors each having a conductive coil, and detect a position of the rotor shaft 113 based on a change in inductance of the conductive coil, which changes in accordance with a position of the rotor shaft 113. 10 The upper radial sensors 107 detect a radial displacement of the rotor shaft 113, i.e. the rotating body 103 fixed to the rotor shaft 113, and send the detected radial displacement to a control device 200.

[0036] In the control device 200, for example, a compensation circuit having a PID adjustment function generates an excitation control command 15 signal for the upper radial electromagnets 104 based on a position signal detected by the upper radial sensors 107. An amplifier circuit (not shown) then controls excitation of the upper radial electromagnets 104 based on the excitation control command signal, thereby adjusting a radial position of an upper side of rotor shaft 113. 20

[0037] The rotor shaft 113 is made of a material with high magnetic permeability (iron, stainless steel, etc.) or the like, and is attracted by magnetic force of the upper radial electromagnets 104. The aforementioned adjustment is independently performed in an X-axis direction and a Y-axis direction. Lower radial electromagnets 105 and 25 lower radial sensors 108 are arranged similarly to the upper radial electromagnets 104 and the upper radial sensors 107, and adjust a radial position of a lower side of the rotor shaft 113 similarly to the radial position of the upper side.

[0038] Further, axial electromagnets 106A and 106B are arranged above 30 and below a disc-shaped metal disc 111 provided at a lower portion of the rotor shaft 113. The metal disc 111 includes a material with high magnetic permeability, such as iron. An axial sensor 109 is provided to detect an axial displacement of the rotor shaft 113 and sends an axial position signal to the control device 200. 35

[0039] In the control device 200, for example, a compensation circuit having a PID adjustment function generates excitation control command signals for the respective axial electromagnets 106A and 106B based on the axial position signal detected by the axial sensor 109. The amplifiercircuit then controls excitation of the axial electromagnets 106A and 106B based on these excitation control command signals, thereby causing the axial electromagnet 106A to attract the metal disc 111 upward with magnetic force and causing the axial electromagnet 106B to attract the 5 metal disc 111 downward to adjust an axial position of the rotor shaft 113.

[0040] The control device 200 thus appropriately adjusts the magnetic force of the axial electromagnets 106A and 106B that is exerted on the metal disc 111, magnetically levitates the rotor shaft 113 in the axial 10 direction, and holds the rotor shaft 113 in the space without contact.

[0041] Meanwhile, a motor 121 has a plurality of pole pieces arranged circumferentially so as to surround the rotor shaft 113. Each pole piece is controlled by the control device 200 so as to drive the rotor shaft 113 to rotate through electromagnetic force acting between the pole piece 15 and the rotor shaft 113. The motor 121 incorporates a rotational speed sensor (not shown), such as a Hall element, a resolver, or an encoder, and a rotational speed of the rotor shaft 113 is detected using a detection signal of this rotational speed sensor.

[0042] Furthermore, a phase sensor (not shown) is attached near the 20 lower radial sensors 108, for example, to detect a phase of rotation of the rotor shaft 113. The control device 200 detects positions of the pole pieces using detection signals of both the phase sensor and the rotational speed sensor.

[0043] A plurality of stator blades 123 (123a, 123b, 123c ...) are 25 arranged with small gaps from the rotor blades 102 (102a, 102b, 102c ...). The rotor blades 102 (102a, 102b, 102c ...) are each inclined by a predetermined angle from a plane perpendicular to an axis of the rotor shaft 113 to transfer molecules of exhaust gas molecules downward by means of collision. The stator blades 123 (123a, 123b, 123c, ...) are 30 made of metal such as aluminum, iron, stainless steel, copper, or an alloy containing these metals as components.

[0044] The stator blades 123 are also similarly inclined by a predetermined angle from a plane perpendicular to the axis of the rotor shaft 113 and arranged inward of the outer tube 127 and alternately with 35 levels of the rotor blades 102. An outer circumferential edge of each stator blade 123 is supported in a state inserted between a plurality of stacked stator blade spacers 125 (125a, 125b, 125c, ...).

[0045] Each stator blade spacer 125 is an annular member and made ofmetal such as aluminum, iron, stainless steel, copper, or an alloy containing these metals as components. The outer tube 127 is fixed to outer circumferential portions of the stator blade spacers 125 with a small gap therebetween. A base portion 129 is disposed at a bottom of the 5 outer tube 127. The base portion 129 has an outlet port 133, which communicates with the outside. Exhaust gas that has entered the inlet port 101 from a chamber (vacuum chamber) side and been transferred to the base portion 129 is sent to the outlet port 133.

[0046] Further, a threaded spacer 131 is disposed between a lower 10 stator blade spacer 125 and the base portion 129 due to an application of the turbomolecular pump 100. 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 thread groove 131a with a plurality of helical threads engraved on an inner-circumferential 15 surface. The direction of the helix of the thread groove 131a is a direction in which the molecules of the exhaust gas are transferred towards the outlet port 133 when these molecules move in a rotational direction of the rotating body 103. A cylindrical portion 102d hangs down from a lowermost portion continuous with the rotor blades 102 (102a, 20 102b, 102c, ...) of the rotating body 103. An outer-circumferential surface of the cylindrical portion 102d has a cylindrical shape, protrudes toward the inner-circumferential surface of the threaded spacer 131, and is located close to the inner-circumferential surface of the threaded spacer 131 with a predetermined gap therebetween. The exhaust 25 gas that has been transported to the thread groove 131a by the rotor blades 102 and the stator blades 123 is guided by the thread groove 131a and sent to the base portion 129.

[0047] The base portion 129 is a disc-shaped member that constitutes a base of the turbomolecular pump 100 and is commonly made of metal such as 30 iron, aluminum, or stainless steel. Since the base portion 129 not only physically holds the turbomolecular pump 100 but also functions as a thermal conduction path, it is preferable to use metal that is rigid and has high thermal conductivity, such as iron, aluminum, or copper.

[0048] When, in this configuration, the rotor blades 102 are driven to 35 rotate together with the rotor shaft 113 by the motor 121, exhaust gas is sucked from the chamber through the inlet port 101 due to action of the rotor blades 102 and the stator blades 123. The rotation speed of the rotor blades 102 is normally 20000 rpm to 90000 rpm, and thecircumferential speed at outer ends of the rotor blades 102 reaches 200 m / s to 400 m / s. The exhaust gas sucked from the inlet port 101 passes between the rotor blades 102 and the stator blades 123 and is transferred to the base portion 129. At this time, the temperature of the rotor 5 blades 102 rises due to frictional heat generated when the exhaust gas comes into contact with the rotor blades 102 and conduction of heat generated in the motor 121, and this heat is transmitted toward the stator blades 123 due to radiation or by being conducted by gas molecules of the exhaust gas, for example. 10

[0049] The stator blade spacers 125 are joined to each other at their outer-circumferential portions, and transmit, to the outside, heat received by the stator blades 123 from the rotor blades 102 and frictional heat generated when the exhaust gas comes into contact with the stator blades 123. 15

[0050] Note that in the above description, the threaded spacer 131 is disposed on an outer circumferential portion of the cylindrical portion 102d of the rotating body 103, and the thread groove 131a is engraved on the inner-circumferential surface of the threaded spacer 131. However, there may also be a case where, conversely, a thread groove is engraved 20 on the outer-circumferential surface of the cylindrical portion 102d, and a spacer having a cylindrical inner-circumferential surface is disposed around the thread groove.

[0051] Depending on the application of the turbomolecular pump 100, there may also be a case where, in order to prevent the gas sucked from 25 the inlet port 101 from entering an electrical section that includes the upper radial electromagnets 104, the upper radial sensors 107, the motor 121, the lower radial electromagnets 105, the lower radial sensors 108, the axial electromagnets 106A and 106B, the axial sensor 109, and so on, the electrical section is covered on all sides with a stator column 122, 30 and the inside of this stator column 122 is kept at a predetermined pressure by a purge gas.

[0052] In this case, a pipe (not shown) is disposed in the base portion 129, and the purge gas is introduced through this pipe. The introduced purge gas is sent to the outlet port 133 through gaps between 35 a protective bearing 120 and the rotor shaft 113, between a rotor and a stator of the motor 121, and between the stator column 122 and inner- circumferential cylindrical portions of the rotor blades 102.

[0053] Here, the turbomolecular pump 100 requires control based onmodel identification and individually adjusted unique parameters (e.g. characteristics corresponding to the model). To store the control parameters, the turbomolecular pump 100 includes an electronic circuit portion 141 in a main body. The electronic circuit portion 141 includes a 5 semiconductor memory such as an EEP-ROM, an electronic component such as a semiconductor element for accessing the semiconductor memory, a substrate 143 for mounting these members. The electronic circuit portion 141 is housed below the rotational speed sensor (not shown) near, for example, the center of the base portion 129 that constitutes a lower part 10 of the turbomolecular pump 100, and is closed by an airtight bottom lid 145.

[0054] In a semiconductor manufacturing process, some type of process gas introduced into the chamber have a property of turning to solid when the pressure of the gas exceeds a predetermined value or when the 15 temperature falls below a predetermined value. Inside the turbomolecular pump 100, the pressure of the exhaust gas is lowest at the inlet port 101 and highest at the outlet port 133. If the pressure of the process gas becomes higher than a predetermined value or the temperature of the process gas becomes lower than a predetermined value while the process 20 gas is transferred from the inlet port 101 to the outlet port 133, the process gas becomes solid and is adhered and deposited inside the turbomolecular pump 100.

[0055] When, for example, SiCl4is used as a process gas in an Al etching device, at low vacuum (760 [torr] to 10-2[torr]) and low 25 temperature (about 20 [°C]), a solid product (e.g. AlCl3) is precipitated, and is adhered and deposited inside the turbomolecular pump 100, as indicated by a vapor pressure curve. If a process gas precipitate builds up inside the turbomolecular pump 100, the precipitate narrows the pump flow path and causes deterioration of performance of the turbomolecular 30 pump 100. The aforementioned product is likely to coagulate and adhere in high-pressure areas near the outlet port 133 and near the threaded spacer 131.

[0056] To address this issue, a heater (not shown) or an annular water-cooling tube 149 is wound around an outer peripheral portion of the 35 base portion 129 or the like, and a temperature sensor (e.g. thermistor) is embedded near the heater, for example. Heating with the heater and cooling with the water-cooling tube 149 are controlled (hereinafter referred to as TMS; Temperature Management System) based on a signal fromthe temperature sensor so as to keep the temperature of the base portion 129 at a constant high temperature (set temperature). The water-cooling tube 149 is provided with a water-cooling valve (not shown) to control cooling. 5

[0057] Next, the interface circuit of the vacuum pump system, which is the present embodiment, is described. Fig. 3 is a block diagram of the interface circuit. First, Fig. 3 illustrates a method in which the interface circuit collects and holds information regarding all pumps in advance. 10 In Fig. 3, the interface circuit 23 includes a communication frame receiver 25 that receives a communication frame 20 transmitted from an external device, such as the customer supervisory control tool 1.

[0058] As shown in Fig. 4, the communication frame 20 includes a pump position 27 for identify one of the plurality of vacuum pumps connected 15 to the integration unit 400, and a command 29. This command 29 may be either an operation command or an information acquisition command, and an operation command / information acquisition command distinguisher 31 determines which command is included.

[0059] If the operation command / information acquisition command 20 distinguisher 31 determines that an operation command is included, the communication frame 20 is passed to an operation processor 30. On the other hand, if it is determined that an information acquisition command is included, the communication frame 20 is passed to an information acquisition processor 40. 25 In the operation processor 30, a pump position analyzer 33 analyzes which vacuum pump 100 is to be operated, and an operation type analyzer 35 analyzes an operation type. An operation command transmitter 37 receives the pump position 27 and the operation type, and transmits an operation command to the vacuum pump designated as the pump position 27. 30

[0060] A response receiver 38 receives a response signal from the vacuum pump 100, and a reply frame creator 39 creates a reply frame based on content of the response. The reply frame created by the reply frame creator 39 is transmitted to an external device, such as the customer supervisory control tool 1, via a communication frame transmitter 41. 35 Meanwhile, in the information acquisition processor 40, a pump position analyzer 42 analyzes which vacuum pump 100 an information acquisition instruction is directed to. Further, an acquired information type analyzer 43 analyzes which type of information regarding the vacuumpump 100 is to be acquired.

[0061] An all-pump information collector 45 periodically collects information regarding all pumps asynchronously with reception of an information acquisition command from an external device. 5 The all-pump information collector 45 transmits an information acquisition command to a first pump via an information acquisition command transmitter 46 in order to acquire one or more pieces of information regarding the first pump. A reply receiver 47 receives a response from the vacuum pump 100 and passes the one or more pieces of10 information regarding the first pump included in the reply to the all- pump information collector 45, which then holds the passed information. If any piece of information regarding the first pump has not yet been acquired, the remaining piece of information is acquired in the same procedure and held by the all-pump information collector 45. After all 15 pieces of information regarding the first pump have been acquired, information regarding a second pump is subsequently acquired in the same procedure. This procedure is performed for all of the connected vacuum pumps 100.

[0062] Fig. 5 shows an example of data stored in a storage device (not 20 shown) of the all-pump information collector 45. Each address indicates a pump position 27 represented with an address block in a certain large range, such as a multiple of 0x0100. An information type is represented by an offset address of the address block in the pump position 27. That is, for example, an offset address 0x0000 indicates the number of 25 rotations, and 0x0002 indicates a motor current. The thus-configured data covers the plurality of vacuum pumps and includes a plurality of information types such as the number of rotations and a motor current and data pertaining to these information types, but can be stored as one integrated piece of information in a storage means. 30 The storage means thus requires only a small storage area. Furthermore, compared to a conventional case in which a storage means is provided for an interface circuit 13 of each vacuum pump, the present embodiment requires only one storage means, which is space-saving. Thus, an inexpensive configuration is realized. 35

[0063] In Fig. 3, when receiving an information acquisition command from an external device, a reply information selector 44 makes an inquiry to the all-pump information collector 45 based on the pump position 27 and the acquired information type. The all-pump information collector 45searches for information to be returned to the external device from the held information, and returns the information to the reply information selector 44. The reply information selector 44 passes this information to the 5 reply frame creator 48, which creates a reply frame. The created reply frame is transmitted to an external device, such as the customer supervisory control tool 1, via the communication frame transmitter 41.

[0064] As described above, with the interface circuit of the present embodiment, communication of the operation signal and the acquired 10 information signal with the plurality of control devices is integrated using one interface circuit, thereby reducing the cost and the necessary space compared to a conventional case in which a plurality of pumps require the same number of interface circuits. Further, communication wiring is simplified, and time and labor for communication wiring is thus 15 simplified. In addition, information acquired by the all-pump information collector 45 can constantly be kept up-to-date by regularly acquiring information regarding the plurality of vacuum pumps 100. This makes it possible, when an information acquisition command is received, to quickly 20 extract necessary information in accordance with content of the information acquisition command.

[0065] Next, a method of sequentially collecting information regarding a pump each time an information acquisition command is transmitted is described with reference to Fig. 6. Note that the same elements as those 25 in Fig. 3 are assigned the same reference numerals, and a description thereof is omitted. In Fig. 6, the interface circuit 23 includes the communication frame receiver 25 that receives the communication frame 20, in the same manner as Fig. 3. The communication frame 20 includes a pump position 27 for 30 identify one of the plurality of vacuum pumps connected to the integration unit 400, and a command 29. This command 29 may be either an operation command or an information acquisition command, and the operation command / information acquisition command distinguisher 31 determines which command is included. 35

[0066] If the operation command / information acquisition command distinguisher 31 determines that an operation command is included, the communication frame 20 is passed to an operation processor 30. On the other hand, if it is determined that an information acquisition commandis included, the communication frame 20 is passed to an information acquisition processor 40. In the information acquisition processor 40, the pump position analyzer 42 analyzes which vacuum pump 100 an information acquisition 5 instruction is directed to. Further, the acquired information type analyzer 43 analyzes which type of information regarding the vacuum pump 100 is to be acquired.

[0067] An information acquisition command transmitter 49 receives the pump position 27 and the acquired information type, and transmits an 10 information acquisition command to a vacuum pump 100 designated as the pump position 27. A response receiver 51 receives a response from the vacuum pump 100, and a reply frame creator 53 creates a reply frame based on content of the response. The created reply frame created is transmitted to an external device, such as the customer supervisory 15 control tool 1, via the communication frame transmitter 41.

[0068] Thus, the interface circuit is configured such that communication of operation signals and acquired information signals with the plurality of control devices is integrated using one interface circuit, thereby reducing the cost and the necessary space compared to a 20 conventional case in which a plurality of pumps requires the same number of interface circuits. Further, communication wiring is simplified, and time and labor for communication wiring is thus simplified. Furthermore, when an information acquisition command is received, information is sequentially extracted from the control device 300 based 25 on the pump position 27 and the acquired information type that are obtained by analyzing the command. This eliminates the need for the interface circuit 23 to have a large-capacity storage means.

[0069] Next, a description is given of application of a supervisor circuit that monitors information acquired by the information acquisition 30 processor and detect abnormalities. Note that the same elements as those in Fig. 3 are assigned the same reference numerals, and a description thereof is omitted. In Fig. 1, the supervisor circuit 11 is included in the control device 300 in correspondence with each turbomolecular pumps 100. However, 35 in this example, the supervisor circuit as well as the interface circuit are accommodated in an integration unit 600 and configured as an interface-supervisor circuit 50, as shown in the overall configuration diagram in Fig. 7 and the block diagram of the interface circuit thatincludes a supervisor circuit in Fig. 8.

[0070] In Fig. 8, the interface-supervisor circuit 50 has a supervisor module 55 in addition to the functions of the interface circuit. The supervisor module 55 constantly references information regarding each 5 pump that is updated in real time by the all-pump information collector 45, and monitors the status of the pump. If an abnormality is found, a transmission command is used to perform processing such as stopping a relevant pump.

[0071] Next, an example in which the integration unit is provided with 10 an input device and a display device is described. Fig. 9 is an overall configuration diagram in which the input device and the display device are provided, and Fig. 10 is a block diagram of the interface circuit. Note that the same elements as those in Fig. 3 are assigned the same reference numerals, and a description thereof is omitted. 15 In Fig. 9, an input device 61 having key switches or the like, and a display device 63, such as an LCD, are connected to the interface circuit 23.

[0072] In Fig. 10, the interface circuit 23 has a key input reader 65 that reads input from the input device 61 such as key switches. Key input 20 refers to a certain kind of operation performed for any of the plurality of vacuum pumps 100 connected to the interface circuit 23, and is represented by, for example, a key type and a key operation method. The pump position analyzer 33 and the operation type analyzer 35 analyze the pump position 27 and an operation type represented by the key 25 type and the key operation method. The operation command transmitter 37 receives the pump position 27 and the operation type, and transmits an operation command to a vacuum pump 100 designated as the pump position 27.

[0073] The response receiver 38 receives a response signal from the 30 vacuum pump 100, and a display data creator 67 creates display data based on content of the response. The created display data is output to the display device 63 via a display data output module 69. The all-pump information collector 45 periodically collects information regarding all pumps asynchronously with reception of an information acquisition command 35 from an external device. A display information selector 71 makes an inquiry to the all-pump information collector 45 based on the pump position 27 and the acquired information type at any timing. In response to this inquiry, the all-pump information collector 45 searches forinformation to be displayed on the external device from the held information, and returns the information to be displayed to the display information selector 71. Here, “any timing” refers to, for example, switching the pump information to be displayed at regular intervals, or 5 switching a pump to be displayed by operating a key for switching the display.

[0074] The display information selector 71 passes the information acquired from the all-pump information collector 45 to a display data creator 73, which creates display data. The created display data is 10 output to the display device 63 via a display data output module 69. Thus, attaching the key input reader 65 and the display data output module 69 to the interface circuit 23 allows work to be performed efficiently at sites closer to the vacuum pumps 100.

[0075] Note that each control device 300 includes a plurality of 15 circuits such as the motor control circuit 5, the magnetic bearing control circuit 7, the TMS control circuit 9, and the supervisor circuit 11, and here, it is desirable that one common communication standard is used between the interface circuit 23 and the control device 300. With this, only one type of distribution cable and one type of receiving 20 function installed in the plurality of the control devices are required, thereby reducing the cost. Note that the present invention can be modified and combined in various manners without departing from the spirit of the invention, and it is obvious that the invention extends to such modifications and 25 combinations.

[0076] 1 Customer supervisory control tool 3 Communication interface cable 5 Motor control circuit 30 7 Magnetic bearing control circuit 9 TMS control circuit 11 Supervisor circuit 13, 23 Interface circuit 15 Power supply circuit 35 20 Communication frame 25 Communication frame receiver 27 Pump position 29 Command30 Operation processor 31 Operation command / information acquisition command distinguisher 33 Pump position analyzer 35 Operation type analyzer 5 37 Operation command transmitter 38 Response receiver 39 Reply frame creator 40 Information acquisition processor 41 Communication frame transmitter 10 42 Pump position analyzer 43 Acquired information type analyzer 44 Reply information selector 45 All-pump information collector 46 Information acquisition command transmitter 15 47 Reply receiver 48 Reply frame creator 49 Information acquisition command transmitter 50 Interface-supervisor circuit 51 Response receiver 20 53 Reply frame creator 55 Supervisor module 61 Input device 63 Display device 65 Key input reader 25 67 Display data creator 69 Display data output module 71 Display information selector 73 Display data creator 100 Turbomolecular pump 30 200, 300 Control device 400, 600 Integration unit

Claims

CLAIMS

1. A vacuum pump system comprising: a plurality of vacuum pumps; and 5 a plurality of control devices configured to control the plurality of vacuum pumps in one-to-one correspondence; and an interface circuit disposed independently of the plurality of control devices and including: an operation processor configured to integrate communication of peration signal and an acquired information signal with the plurality ontrol devices and to control each of the control devices; and an information acquisition processor configured to acquire rmation from the plurality of control devices. im 2] The vacuum pump system according to claim 1, wherein the interface circuit further includes: an input-output means for monitoring and controlling the plurality ontrol device; and a signal analysis means for receiving, from the input-output means, gnal including: a pump position for identifying one of the plurality acuum pumps; and a command being an operation command or an rmation acquisition command, and analyzing the signal, if a result of the signal analysis means analyzing the signal cates that the command included in the signal is the operation and, the command is passed to the operation processor, and if a result of the signal analysis means analyzing the signal cates that the command included in the signal is the information isition command, the command is passed to the information acquisition essor. im 3] The vacuum pump system according to claim 1 or 2, further comprising a power supply portion configured to supply electric power to the ality of control devices, the power supply portion being integrated the interface circuit into an integration unit and disposed pendently of the plurality of control devices. im 4] The vacuum pump system according to claim 2, wherein the information acquisition processor includes an all-pumpinformation collector configured to regularly acquire information regarding the plurality of vacuum pumps and hold the acquired information, and when the command included in the signal is received, necessary 5 information is extracted from the all-pump information collector based on the pump position and the acquired information type that are obtained by analyzing the command, and the input-output means outputs the extracted information to an external device.

5. The vacuum pump system according to claim 2, wherein when the command included in the signal is received, the rmation acquisition processor sequentially acquires information from plurality of control devices based on the pump position and the ired information type that are obtained by analyzing the command, and input-output means outputs the acquired information to an external ce. im 6] The vacuum pump system according to any one of claims 1, 4, or 5, her comprising a supervisor module configured to monitor information acquired by information acquisition processor, and if an abnormality is found, a corresponding pump out of the plurality of vacuum pump. im 7] The vacuum pump system according to claim 1 or 2, wherein one common communication standard is used as a communication dard between the interface circuit and the plurality of control ces. im 8] The vacuum pump system according to claim 3, further comprising: a key input reader configured to read a signal of key input and pass nput signal to the operation processor to perform an operation cated by the key input; and isplay data output module configured to display a signal extracted by information acquisition processor, wherein the key input reader and the display data output module are ched to the integration unit. im 9] An interface circuit to be mounted in a vacuum pump system thatincludes: a plurality of vacuum pumps; and a plurality of control devices configured to control the plurality of vacuum pumps in one-to-one correspondence, the interface circuit disposed independently of the plurality of 5 control devices and comprising: an operation processor configured to integrate communication of an operation signal and an acquired information signal with the plurality of control devices and to control each of the control devices; and an information acquisition processor configured to acquire rmation from the plurality of control devices. im 10] The interface circuit according to claim 9, wherein the interface circuit is integrated with a power supply ion configured to supply electric power to the plurality of control ces, and is disposed independently of the plurality of control ces. im 11] The interface circuit according to claim 9 or 10, further comprising a supervisor module configured to monitor information acquired by information acquisition processor, and if an abnormality is found, a corresponding pump out of the plurality of vacuum pump.

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