Conveying system, control system, and control method

Abstract

To provide a conveying system, a control system, and a control method that can reduce a variation in speed of a movable element, while ensuring a high degree of freedom in design.SOLUTION: A conveying system has: a conveyance path that has a plurality of coils arranged in a predetermined direction; a position detection unit that is arranged along the predetermined direction and detects the position of a movable element having a plurality of magnet parts; and a control unit that supplies current to the plurality of coils to control the movement of the movable element. The control unit selects, from the plurality of coils, a coil for controlling the movement of the movable element according to the position of the movable element, calculates the thrust constant of the selected coil based on the position of the selected coil and the positions of the magnet parts, distributes a thrust against the movable element to the selected coil, and determines the current value of the selected coil based on the thrust constant and the distributed thrust.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a transport system, a control system, and a control method. [Background technology]

[0002] Patent Document 1 describes a mobile body system that includes a moving path in which S poles and N poles are alternately arranged, a moving body that moves along the moving path, and the moving body has a plurality of motors arranged at different positions in the moving direction, and a drive control unit that controls the driving of the motors. In the mobile body system described in Patent Document 1, when one motor is located in an irregular section where the arrangement of the magnetic poles of the magnets is irregular, at least one motor other than the one motor is located in a section that is not the irregular section, and the drive control unit stops driving the motor located in the irregular section.

[0003] Also, Patent Document 2 describes a conveyance system in which a plurality of individual motors, each capable of functioning as a primary armature of one independent linear motor, are arranged at intervals along a rail over the entire traveling area of ​​a traveling body. In the conveyance system described in Patent Document 2, a mover made of a permanent magnet is installed on the traveling body, and the length of the mover in the traveling direction is set to a length that faces the plurality of individual motors no matter where the mover is in the traveling direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6314371 [Patent Document 2] Patent No. 5423901 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conveyance systems described in Patent Documents 1 and 2, it is difficult to arrange the stators in a regular order. Therefore, there is a risk of the speed fluctuation of the mover occurring in the conveyance systems described in Patent Documents 1 and 2. On the other hand, if the individual motors on the stator side are arranged to satisfy a predetermined rule as described in Patent Document 2, it is difficult to ensure a high degree of design freedom.

[0006] The present invention has been made to solve the above-mentioned problems, and has an object to provide a conveying system, a control system, and a control method that can reduce the speed fluctuation of a mover while ensuring high design freedom. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a conveying system according to one aspect of the present invention has a conveying path having a plurality of coils arranged in a predetermined direction, a position detection unit that detects the position of a mover arranged along the predetermined direction and having a plurality of magnet portions, and a control unit that controls the movement of the mover by supplying current to the plurality of coils, wherein the control unit selects a coil from the plurality of coils that controls the movement of the mover in accordance with the position of the mover, calculates a thrust constant of the selected coil based on the position of the selected coil and the position of the magnet portion, distributes thrust against the mover to the selected coil, and determines a current value of the selected coil based on the thrust constant and the distributed thrust.

[0008] A control system according to another aspect of the present invention is a control system for controlling a conveying system having a conveying path having a plurality of coils arranged in a predetermined direction, and a position detection unit that detects the position of a mover having a plurality of magnet portions arranged along the predetermined direction, and the control system has a selection means for selecting a coil from the plurality of coils that controls the movement of the mover in accordance with the position of the mover, a calculation means for calculating a thrust constant of the selected coil based on the position of the selected coil and the position of the magnet portion, a distribution means for distributing thrust against the mover to the selected coil, a determination means for determining a current value of the selected coil based on the thrust constant and the distributed thrust, and a control means for controlling the movement of the mover by supplying a current of the determined current value to the selected coil.

[0009] A control method according to yet another aspect of the present invention is a control method for a conveying system having a conveying path having a plurality of coils arranged in a predetermined direction, and a position detection unit arranged along the predetermined direction and detecting the position of a mover having a plurality of magnet portions, the control method comprising the steps of: selecting a coil from the plurality of coils to control movement of the mover in accordance with the position of the mover; calculating a thrust constant from the position of the selected coil and the position of the magnet portion; distributing thrust against the mover to the selected coil; determining a current value of the selected coil based on the thrust constant and the distributed thrust; and supplying a current of the determined current value to the selected coil to control the movement of the mover. Effect of the Invention

[0010] According to the present invention, it is possible to reduce the speed fluctuation of the mover while ensuring a high degree of design freedom. [Brief description of the drawings]

[0011] [Figure 1A] 1 is a schematic configuration diagram showing a transport device in a transport system according to a first embodiment of the present invention. [Figure 1B]1 is a schematic configuration diagram showing a transport device in a transport system according to a first embodiment of the present invention. [Figure 1C] 1 is a schematic configuration diagram showing a transport device in a transport system according to a first embodiment of the present invention. [Figure 1D] 1 is a schematic configuration diagram showing a transport device in a transport system according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a schematic configuration diagram showing a control system in a transport system according to a first embodiment of the present invention. [Diagram 3] 1 is a block diagram showing a transport system according to a first embodiment of the present invention. [Figure 4] FIG. 2 is a schematic diagram illustrating an operation of the transport system according to the first embodiment of the present invention. [Figure 5A] 13A to 13C are schematic diagrams illustrating the operation of the transport system according to the third embodiment of the present invention. [Figure 5B] 13A to 13C are schematic diagrams illustrating the operation of the transport system according to the third embodiment of the present invention. [Figure 5C] 13A to 13C are schematic diagrams illustrating the operation of the transport system according to the third embodiment of the present invention. [Figure 6] FIG. 11 is a flowchart showing the operation of the transport system according to the fourth embodiment of the present invention. [Figure 7] FIG. 13 is a schematic configuration diagram showing a transport device in a transport system according to a fifth embodiment of the present invention. [Figure 8] 13A to 13C are schematic views illustrating the operation of the transport system according to the fifth embodiment of the present invention. [Figure 9] FIG. 13 is a block diagram showing a transport system according to a sixth embodiment of the present invention. [Figure 10A] FIG. 13 is a schematic configuration diagram showing a conveying device according to a sixth embodiment of the present invention. [Figure 10B] FIG. 13 is a schematic configuration diagram showing a conveying device according to a sixth embodiment of the present invention. [Figure 10C] FIG. 13 is a schematic configuration diagram showing a conveying device according to a sixth embodiment of the present invention. [Figure 11]FIG. 13 is a schematic configuration diagram showing a transport system in a transport system according to a seventh embodiment of the present invention. [Figure 12] FIG. 13 is a block diagram showing a transport system according to a seventh embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [First embodiment] A transport system according to a first embodiment will be described with reference to Fig. 1A to Fig. 4. The transport system according to this embodiment is a transport system using a moving magnet type (MM) linear motor in which a permanent magnet is installed in the mover and a coil is installed in the stator.

[0013] First, the schematic configuration of the transport system according to the present embodiment will be described with reference to FIGS. 1A to 3. FIGS. 1A to 1D are schematic configuration diagrams showing the transport device 12 in the transport system 1 according to the present embodiment. FIG. 1A is a top view of the transport device 12 as seen from the Z direction. FIG. 1B is a front cross-sectional view of the transport device 12 as seen from the X direction. FIG. 1C is a top view of the coil unit 21 in the transport device 12 as seen from the Z direction. FIG. 1D is a side view of the coil unit 21 in the transport device 12 as seen from the Y direction. FIG. 2 is a schematic configuration diagram showing the control system 13 in the transport system 1 according to the present embodiment. FIG. 3 is a block diagram showing the transport system 1 according to the present embodiment. In the following description, for multiple components, lowercase alphabets are added after the numerals as necessary to distinguish them from one another, and when no particular distinction is required, a common numeral-only symbol is used.

[0014] As shown in Figs. 1A, 1B and 2, the transport system 1 according to this embodiment includes a transport device 12 and a control system 13. The transport device 12 has a carrier 40 that functions as a mover. The number of carriers 40 is not limited to one as shown in Fig. 1A, and may be two or more. The control system 13 functions as a control unit that controls the transport device 12 and controls the transport of the carrier 40 in the transport device 12. The transport system 1 constitutes a part of a processing system that processes a workpiece transported by the carrier 40.

[0015] Here, each coordinate axis, direction, etc. of the XYZ coordinate system, which is an orthogonal coordinate system used in the following description, will be defined. First, the X axis is taken along the horizontal direction, which is the transport direction of the carrier 40, and the transport direction of the carrier 40 is the X direction. The Z axis is taken along the vertical direction, which is a direction perpendicular to the X direction, and the vertical direction is the Z direction. The Y axis is taken along a direction perpendicular to the X direction and the Z direction, and the direction perpendicular to the X direction and the Z direction is the Y direction. The direction in which the carrier 40 is transported is the positive direction of the X direction. The vertical upward direction is the positive direction of the Z direction. Note that the transport direction of the carrier 40 does not necessarily have to be the horizontal direction, but in that case, the transport direction can be similarly defined as the X direction, and the Y direction and the Z direction can be similarly defined.

[0016] As shown in FIGS. 1A and 1B, the transport device 12 has a carrier 40 that functions as a mover, and a transport path 3 that includes a coil unit 21 that functions as a stator.

[0017] The carrier 40, for example, serves as a cart for transporting a workpiece in a production line of a processing system. The carrier 40 is configured, for example, so as to be able to hold a workpiece on its upper surface. The production line is provided with one or more types of process devices 14 that process the workpiece transported by the carrier 40. In the production line, for example, the process devices 14 process the workpiece that has been transported to a workspace by the transport device 12 or the workpiece being transported by the transport device 12 to manufacture an article. The number of carriers 40 arranged on the transport device 12 varies depending on the production line.

[0018] The carrier 40 has rollers 44 mounted on its underside, which is the negative surface in the Z direction, that can run along the rail 60 of the conveying path 3. The carrier 40 also has a plurality of permanent magnets 42 mounted on its underside along the X direction so as to face the coil 22 of the conveying path 3. The plurality of permanent magnets 42 are alternately magnetized and mounted so that the polarity of the outer magnetic poles facing downward on the conveying path 3 side is alternately different, and the polarity of the S poles and the N poles are alternately arranged in the X direction on the outside. Each permanent magnet 42 constitutes a magnet part in which a force acts between the coil 22 of the conveying path 3 to which a current is applied. The number of the plurality of permanent magnets 42 is not particularly limited and can be changed as appropriate. The carrier 40 also has a scale 41 mounted on it so as to be readable by the encoder 31.

[0019] The carrier 40 is configured to be movable in the X direction along the rail 60 by, for example, rotating the roller 44 about a rotation axis along the Y direction, using the force in the X direction acting between the permanent magnet 42, which is the magnet portion, and the coil 22 to which a current is applied of the transport path 3 as a thrust. The carrier 40 can also be configured to move in the X direction while levitating in the Z direction, using the force in the Z direction acting between the permanent magnet 42 and the coil 22 to which a current is applied of the transport path 3 as a levitation force.

[0020] The conveying path 3 has a rail 60 along which the carrier 40 can run in the X direction, a rail support section 61, a plurality of coil units 21, and a plurality of encoders 31. The number of the plurality of coil units 21 and the number of the plurality of encoders 31 are not particularly limited, and can be appropriately changed according to the length of the conveying path 3, etc. The rail 60, the plurality of coil units 21, and the plurality of encoders 31 are attached and installed on the rail support section 61. The rail 60 is installed along the X direction. The plurality of coil units 21a to 21n are arranged along the rail 60 along the X direction. The plurality of encoders 31a to 31c are arranged and installed so as to be lined up at predetermined intervals along the X direction.

[0021] Each encoder 31 internally stores its own mounting position on the transport path 3. The encoder 31 reads the pattern of the scale 41 of the carrier 40 to calculate the relative distance between the encoder 31 and the scale 41. The encoder 31 also calculates the current position of the carrier 40 on the transport path 3 from the calculated relative distance and the mounting position. The encoder 31 also transmits position information indicating the calculated current position of the carrier 40 to the sensor controller 30. In this way, each encoder 31 functions as a position detection unit that detects the position of the carrier 40 on the transport path 3.

[0022] Each coil unit 21 has a plurality of coils 22. As shown in FIG. 1C and FIG. 1D, a plurality of coils 22a to 22f are attached and installed in the coil unit 21 along the X direction. The plurality of coils 22a to 22f are installed so as to be able to face the permanent magnets 42 of the carrier 40. The number of the plurality of coils 22 is not particularly limited and can be changed as appropriate. A coil controller 20 that controls the current flowing through each of the coils 22 is connected to each of the coils 22. The coils 22 are excited by application of a current controlled by the coil controller 20. The excited coils 22 drive the carrier 40 by a force generated by interaction with the permanent magnets 42 of the carrier 40, and transport the carrier 40 in the X direction.

[0023] As shown in FIG. 2, the control system 13 includes a transport controller 10, a plurality of coil controllers 20, and a sensor controller 30. The plurality of coil controllers 20a to 20n are installed corresponding to the plurality of coil units 21a to 21n. The plurality of coil controllers 20 are communicably connected to the transport controller 10 as a transport control means. The sensor controller 30 is communicably connected to the transport controller 10. The corresponding coil unit 21 is connected to each coil controller 20. The sensor controller 30 is communicably connected to a plurality of encoders 31. The control system 13 functions as a control unit that controls the movement of the carrier 40 on the transport path 3 by supplying a driving current to the plurality of coils 22 on the transport path 3.

[0024] The transport controller 10 determines a control current value indicating the current value to be applied to the coil 22 of the coil unit 21 based on position information indicating the current position of the carrier 40 transmitted from the sensor controller 30. The transport controller 10 transmits the determined control current value to each coil controller 20. Each coil controller 20 controls the amount of current to be applied to the coil 22 of the corresponding coil unit 21 based on the control current value received from the transport controller 10. The sensor controller 30 transmits position information indicating the current position of the carrier 40 transmitted from the encoder 31 to the transport controller 10. Each component of the control system 13 will be described in detail below.

[0025] 3, the sensor controller 30 has a position information selector 110. The transport controller 10 has a position command unit 100, a control deviation calculator 101, a position controller 102, a control coil selector 103, an electrical angle calculator 104, a device information storage unit 105, a control information output unit 106, and a distribution amount calculator 107.

[0026] A plurality of encoders 31 are connected to the position information selector 110. The position information selector 110 stores a switching position on the transport path 3 for switching the encoder 31 that acquires the current position of the carrier 40. When the current position of the carrier 40 passes the switching position on the transport path 3, the position information selector 110 switches the encoder 31 that acquires the current position to the encoder 31 on the side where the carrier 40 has passed the switching position.

[0027] The position command device 100 outputs position command information of the carrier 40 to the control deviation calculator 101. The position command information of the carrier 40 is information indicating the position where the carrier 40 to be transported should be positioned.

[0028] The control deviation calculator 101 calculates the difference between the position indicated by the position command information output from the position command device 100 and the current position of the carrier 40 indicated by the position information output from the sensor controller 30. In addition, the control deviation calculator 101 outputs the calculated position difference to the position controller 102 as control deviation information.

[0029] The position controller 102 calculates a required thrust [N], which is a thrust to be commanded as a thrust required to be applied to the carrier 40, based on the control deviation information output from the control deviation calculator 101. The position controller 102 outputs required thrust information indicating the calculated required thrust to the distribution amount calculator 107.

[0030] The device information storage unit 105 functions as a storage unit, and stores device configuration information of the transport device 12 in the transport system 1 in advance.

[0031] The device configuration information stored in the device information storage 105 specifically includes, for example, the length of the carrier 40, the attachment position including the position of the permanent magnet 42 in the X direction, the length of the coil 22, the length of the coil unit 21, the coordinates of the arrangement position of the coil unit 21, etc. The device information storage 105 stores the attachment position of the permanent magnet 42 for each of the multiple carriers 40.

[0032] The control coil selector 103 selects the coil 22 facing the permanent magnet 42 of the carrier 40 being transported, and sets it as the pickup coil to be controlled. The pickup coil is the coil 22 for controlling the movement of the carrier 40. The control coil selector 103 selects the coil 22 facing the permanent magnet 42 as the pickup coil using the current position of the carrier 40, the length of the coil unit 21, and the coordinates of the arrangement position of the coil unit 21. The current position of the carrier 40 is indicated by the position information output from the sensor controller 30. The length of the coil unit 21 and the coordinates of the arrangement position of the coil unit 21 are stored in the device information storage 105. The transport controller 10 performs control so as to stop the output of the coil 22 that is not selected as the pickup coil. The control coil selector 103 outputs control coil information that specifies the coil 22 selected as the pickup coil to the electrical angle calculator 104. In this way, the control coil selector 103 selects the coil 22 as the pickup coil from the multiple coils 22 installed on the transport path 3 according to the position of the carrier 40.

[0033] Based on the control coil information output from the control coil selector 103, the electrical angle calculator 104 calculates the electrical angle of the current to be applied to each coil 22 selected as a pickup coil and a thrust constant [N / A] which is the thrust [N] per unit current [A].

[0034] The thrust constant calculated by the electrical angle calculator 104 will be described with reference to Fig. 4. The upper part of Fig. 4 shows a diagram of the carrier 40 and the coil units 21a and 21b facing it as viewed from the Y direction. The lower part of Fig. 4 shows a thrust constant profile 70 indicating the thrust constant at the position in the X direction corresponding to the diagram in the upper part. The thrust constant profile 70 is a graph with the position in the X direction on the horizontal axis and the thrust constant on the vertical axis.

[0035] As shown in the upper part of FIG. 4, in each of the coil units 21a and 21b, the coils 22 are arranged at a pitch of distance L in the X direction. On the other hand, the permanent magnets 42 of the carrier 40 are arranged at a pitch of distance 3 / 2×L in the X direction. Mcyc is a magnetic cycle, which is the distance in the X direction between the permanent magnets 42 of the same polarity in the multiple permanent magnets 42. For simplicity, in the upper part of FIG. 4, the origin Oc of the X direction position of the coil unit 21 is set to the midpoint between the coil units 21a and 21b. Also, the center Om in the X direction of the carrier 40 is set to the center in the X direction of the permanent magnet 42b that is located at the center in the X direction among the multiple permanent magnets 42. The upper part of FIG. 4 shows a case where the origin Oc and the center Om coincide with each other, that is, a case where the position X in the X direction of the carrier 40 is X=0.

[0036] 4 shows a schematic diagram of the magnitude of the thrust in the X direction on the carrier 40 generated when a unit current is applied to each coil 22 of the coil unit 21. For example, the thrust per unit current acting on the coil 22a of the coil unit 21a has a magnitude of Aq(1) in the X direction. Also, for example, the thrust per unit current acting on the coil 22c of the coil unit 21b has a magnitude of Aq(7) in the X direction.

[0037] The electrical angle calculator 104 can use the thrust constant profile 70 to calculate the thrust constant of each coil 22 based on the X-direction position of the coil 22 selected as the pickup coil and the X-direction position of the permanent magnet 42 of the carrier 40. The electrical angle calculator 104 outputs thrust constant information indicating the calculated thrust constant to the distribution amount calculator 107.

[0038] The distribution amount calculator 107 calculates a distribution output thrust, which is a thrust to be distributed to each coil 22 selected as a pickup coil, using the required thrust information output from the position controller 102. That is, the distribution amount calculator 107 calculates the distribution output thrust by the following formula (1) using the required thrust indicated in the required thrust information and the number of pickup coils, which is the number of coils 22 selected as pickup coils. Note that idx will be used hereinafter as a coil index, which is an index for identifying a coil 22. Distributed output thrust (idx) [N] = Required thrust [N] / Number of pickup coils … Equation (1)

[0039] The distribution amount calculator 107 can equally divide and distribute the required thrust to the pickup coils according to formula (1). The distribution amount calculator 107 outputs distributed output thrust information indicating the calculated distributed output thrust to the control information output device 106. In this way, the distribution amount calculator 107 equally divides and distributes the required thrust to be applied to the carrier 40 to the multiple coils 22 selected as pickup coils based on the number of pickup coils.

[0040] Control information output unit 106 calculates and determines a control current value, which is a current value to be applied to coil 22 selected as a pickup coil, using the thrust constant information output from electrical angle calculator 104 and the distributed output thrust information output from distribution amount calculator 107. That is, control information output unit 106 calculates a control current value for each coil 22 selected as a pickup coil by the following equation (2), using the thrust constant indicated in the thrust constant information and the distributed output thrust indicated in the distributed output thrust information. Control current value (idx) [A] = distributed output thrust (idx) [N] / thrust constant (idx) [N / A] … Equation (2)

[0041] In this way, the control information output unit 106 calculates and determines a control current value for each coil 22 selected as a pickup coil based on the thrust constant and the distributed output thrust. The control information output unit 106 transmits the calculated control current value (idx) to the coil controller 20 that controls the coil 22 identified by the coil index idx.

[0042] The coil controller 20 supplies a drive current to the coil 22 identified by the coil index idx, and controls the current value thereof, in accordance with the control current value (idx) transmitted from the control information output device 106, so that the current value flowing through the coil 22 becomes the control current value (idx). In this way, the coil controller 20 controls the current value flowing through each coil 22 selected as a pickup coil. As a result, a drive current is applied to the coil 22 selected as the pickup coil, and a force acts between the coil 22 and the permanent magnet 42, and as a result, a required thrust is applied to the carrier 40, and the carrier 40 is transported in the X direction.

[0043] Conveyance systems using linear motors have been known for some time. For example, conveyance systems are used in production lines for assembling industrial products. Conveyance systems in production lines convey workpieces such as parts between multiple stations within the production line or between production lines. As a conveyance system, a moving coil type linear motor conveyance system using a coil on the mover side and a permanent magnet on the stator side has been proposed. A moving magnet type linear motor conveyance system using a permanent magnet on the mover side and a coil on the stator side has also been proposed.

[0044] Some transport systems have long-distance transport paths, and multiple movers may be transported on one transport path. In addition, multiple movers are transported with a small distance between them to shorten the takt time. Therefore, if there is a section in the transport system that does not contribute to thrust due to partial damage, convenience or constraints of the device design, etc., it becomes difficult to stop transport and continue operating continuously. Furthermore, it is required that multiple movers are arranged in a high density, transported at a constant speed, and continue operating continuously while maintaining the speed even if a temporary abnormality occurs.

[0045] The above-mentioned Patent Documents 1 and 2 describe configurations and methods that enable transportation even in sections that do not contribute to thrust. Patent Document 1 describes a drive method that detects demagnetized magnetic poles and stops the motor in the target area when the mover is a permanent magnet. Patent Document 2 describes a transport configuration that ensures stable movement and thrust by providing regularity to the coil arrangement so that the same number of coils always face the mover.

[0046] However, as described above, it is difficult to design the stators so that they are arranged regularly. For example, in the case shown in Fig. 1A, the distance between coil unit 21b and coil unit 21c in the X direction is wider than the distance between coil unit 21c and coil unit 21d.

[0047] For example, in a transport system for a large-scale vacuum device, a transport path is configured in which a carrier is transported within a series of vacuum chambers of finite length. In the case of a finite chamber length, it is difficult to arrange stators regularly in the chambers. In addition, between the chambers where partitions exist, there are sections where stators are not arranged and therefore do not contribute to thrust.

[0048] Furthermore, if the coil is damaged or broken during continuous operation, fluctuations in thrust will occur if a section that does not contribute to thrust occurs during operation. Also, if a high control current value is continuously applied to the coil for a certain period of time or more, the coil will generate heat and will no longer be able to generate the specified thrust. Therefore, unlike conventional linear motors, it is difficult to continue conveying without speed fluctuations if the coil is damaged during operation or in a regular arrangement.

[0049] When there is a fluctuation in thrust, it is possible to respond to the fluctuation by PID (Proportional Integral Differential) control, but the response speed depends on the calculation device. If the calculation device is made faster, the cost of the calculation device will increase, which is not desirable.

[0050] In Patent Document 1, the arrangement intervals of the stators are assumed to be equal pitch. In addition, Patent Document 1 takes into consideration the phase shift caused by the demagnetization of the magnet, but does not consider the change in the coil. Therefore, in Patent Document 1, the output may differ from the desired thrust depending on the state of the coil.

[0051] In addition, in Patent Document 2, sections that do not contribute to thrust are arranged according to certain rules, so that the coils of the stator are omitted and transportation is performed while ensuring stable movement and thrust. However, in Patent Document 2, it is difficult to provide freedom in device design because it is not possible to provide sections to which the rules do not apply.

[0052] On the other hand, in this embodiment, the coil 22 to be the pickup coil to be controlled is selected and switched according to the position of the carrier 40, and the required thrust is distributed to the selected coil 22. After distributing the required thrust in this manner, in this embodiment, a control current value that realizes the required thrust to be applied to the carrier 40 is determined. As a result, in this embodiment, a constant thrust can be realized even if the number of pickup coils changes depending on the arrangement of the coils 22. Furthermore, in this embodiment, since a constant thrust can be realized even if the number of pickup coils changes, a high degree of design freedom can be ensured.

[0053] Therefore, according to this embodiment, it is possible to perform control that reduces the speed fluctuation of the carrier 40 while ensuring a high degree of design freedom.

[0054] [Second embodiment] A transfer system according to a second embodiment of the present invention will be described below. Note that the same components as those in the first embodiment are given the same reference numerals and descriptions thereof will be omitted or simplified.

[0055] The configuration of the transport system 1 according to this embodiment is basically the same as the configuration of the transport system 1 according to the first embodiment. The transport system 1 according to this embodiment is different from the transport system 1 according to the first embodiment in the calculation method of the distributed output thrust. Hereinafter, the calculation method of the distributed output thrust according to this embodiment will be described.

[0056] The distribution amount calculator 107 uses the required thrust information output from the position controller 102 and the thrust constant information output from the electrical angle calculator 104 to calculate the distribution output thrust to be distributed to each coil 22 selected as a pickup coil.

[0057] In this embodiment, the required thrust is distributed to each coil 22 in proportion to the ratio of the thrust constant of each coil 22 selected as a pickup coil. That is, the distribution amount calculator 107 uses the required thrust indicated in the required thrust information and the thrust constant indicated in the thrust constant information to calculate the distributed output thrust by the following formula (3) and formula (4). Note that Σ is a symbol representing the sum of the values ​​of the formulas on the right side for each index of a specified integer range. ΣAq(idx) represents the sum of the thrust constants of each coil 22 selected as a pickup coil. The ratio coefficient represented by the following formula (3) represents the ratio of the thrust constant of the coil 22 selected as a pickup coil to the sum of the thrust constants of the coil 22. Proportion coefficient [A / N] = 1 / ΣAq(idx) [N / A] … Equation (3) Distributed output thrust (idx) [N] = ratio coefficient [A / N] × thrust constant (idx) [N / A] × required thrust [N] … Equation (4)

[0058] The distribution amount calculator 107 can distribute the required thrust to the pickup coils in proportion to the ratio of the thrust constant according to formulas (3) and (4). The distribution amount calculator 107 outputs distributed output thrust information indicating the calculated distributed output thrust to the control information output device 106. In this way, the distribution amount calculator 107 distributes the required thrust to be applied to the carrier 40 to the multiple coils 22 selected as pickup coils based on the ratio of the thrust constant of the coils 22 selected as pickup coils.

[0059] In this manner, in this embodiment, the required thrust is distributed in proportion to the ratio of the thrust constant to the coils 22 that are pickups to be controlled. As a result, in this embodiment, as in the first embodiment, a constant thrust can be achieved even if the number of pickup coils changes depending on the arrangement of the coils 22, and a high degree of freedom in design can be ensured.

[0060] Therefore, according to this embodiment, it is possible to perform control that reduces the speed fluctuation of the carrier 40 while ensuring a high degree of design freedom.

[0061] [Third embodiment] A conveying system according to a third embodiment of the present invention will be described with reference to Fig. 5A to Fig. 5C. Fig. 5A to Fig. 5C are schematic diagrams for explaining the operation of the conveying system according to this embodiment. Note that components similar to those in the first and second embodiments are given the same reference numerals, and descriptions thereof will be omitted or simplified.

[0062] The configuration of the transport system 1 according to this embodiment is basically similar to the configuration of the transport system 1 according to the first embodiment. The transport system 1 according to this embodiment is different from the transport system 1 according to the first embodiment in that the transport system 1 according to this embodiment distributes the required thrust to each coil 22 selected as a pickup coil in consideration of the thrust transmission efficiency. Specifically, the transport system 1 according to this embodiment is different from the transport system 1 according to the first embodiment in that the transport system 1 according to this embodiment uses a thrust transmission efficiency profile 71 in addition to a thrust constant profile 70.

[0063] 5A, similarly to the first embodiment shown in FIG. 4, the upper part of the figure shows the carrier 40 and the coil units 21a and 21b facing it as viewed from the Y direction, and the lower part shows a thrust constant profile 70 indicating the thrust constant at the position in the X direction corresponding to the upper part of the figure.

[0064] 5B shows a thrust transmission efficiency profile 71 indicating the thrust transmission efficiency at the position in the X direction corresponding to the upper diagram of FIG. 5A. The thrust transmission efficiency profile 71 is a graph with the position in the X direction on the horizontal axis and the thrust transmission efficiency on the vertical axis. According to the thrust transmission efficiency profile 71, inside between the front end and the rear end in the X direction of the carrier 40, the transmission efficiency is constant at 1 indicating the transmission of thrust without loss. On the other hand, at the front end and the rear end in the X direction of the carrier 40, the transmission efficiency gradually decreases from 1 toward the front and rear, respectively, and the loss of thrust gradually increases.

[0065] In this embodiment, the thrust constant indicated in the thrust constant profile 70 is corrected by using the transmission efficiency indicated in the thrust transmission efficiency profile 71. That is, in this embodiment, the electrical angle calculator 104 corrects the thrust constant calculated for each coil 22 selected as a pickup coil by using the transmission efficiency.

[0066] 5C shows a corrected thrust constant profile 72 indicating the corrected thrust constant at a position in the X direction corresponding to the upper diagram in FIG. 5A. The corrected thrust constant is a thrust constant corrected by the transmission efficiency. The corrected thrust constant profile 72 is a graph with the position in the X direction on the horizontal axis and the corrected thrust constant on the vertical axis. The corrected thrust constant profile 72 can be expressed as the product of the thrust constant profile 70 and the thrust transmission efficiency profile 71.

[0067] The electrical angle calculator 104 corrects the thrust constant Aq by using the thrust transmission efficiency Dk according to the following equation (5) to calculate a corrected thrust constant AqDk. The corrected thrust constant profile 72 can be obtained by plotting the corrected thrust constant calculated by equation (5). AqDk(idx)[N / A]=Aq(idx)[N / A]×Dk(idx) …Equation (5)

[0068] The electrical angle calculator 104 outputs thrust constant information indicating the calculated corrected thrust constant to the distribution amount calculator 107 .

[0069] The transport controller 10 uses a corrected thrust constant instead of the thrust constant to calculate the distributed output thrust in the distribution amount calculator 107 and calculates the control current value in the control information output device 106, similar to the first embodiment. This allows the transport controller 10 to control the transport of the carrier 40. Note that the transport controller 10 can also use a corrected thrust constant instead of the thrust constant to calculate the distributed output thrust in the distribution amount calculator 107 and calculate the control current value in the control information output device 106, similar to the second embodiment.

[0070] In this manner, in this embodiment, the transportation of the carrier 40 can be controlled in consideration of the transmission efficiency of the thrust force that decreases at the ends of the carrier 40. Therefore, according to this embodiment, control can be performed that reduces the speed fluctuation of the carrier 40, including the speed fluctuation caused by the ends of the carrier 40.

[0071] In the above, the first embodiment has been described as a case in which the thrust constant is corrected using the thrust transmission efficiency, but in the second embodiment, the thrust constant can also be corrected using the thrust transmission efficiency in a similar manner to the above.

[0072] [Fourth embodiment] A transfer system according to a fourth embodiment of the present invention will be described with reference to Fig. 6. Fig. 6 is a flow chart showing the operation of the transfer system according to this embodiment. Note that components similar to those in the first to third embodiments are given the same reference numerals and descriptions thereof will be omitted or simplified.

[0073] The configuration of the transport system 1 according to this embodiment is basically the same as the configuration of the transport system 1 according to the first embodiment. The transport system 1 according to this embodiment is different from the transport system 1 according to the first embodiment in that the transport controller 10 executes a process to deal with the case where the control current value calculated by the control information output device 106 is a current value that cannot be applied to the coil 22. In the process of determining the control current value, the transport controller 10 executes a process to deal with the case where the control current value is a current value that cannot be applied to the coil 22. The process of determining the control current value in the transport system 1 according to this embodiment will be described below. FIG. 6 shows the process of determining the control current value in the transport system 1 according to this embodiment.

[0074] As shown in FIG. 6, the distribution amount calculator 107 calculates a distribution output thrust for distributing the required thrust to each coil 22 selected as a pickup coil, in the same manner as in the first embodiment (step S301).

[0075] Next, the control information output unit 106 calculates a control current value to be applied to each coil 22 selected as a pickup coil (step S302).

[0076] Next, the control information output unit 106 judges whether or not all of the control current values ​​calculated in the above step S302 are current values ​​that can be applied by the coil controller 20 (step S303). The control information output unit 106 judges whether or not the current values ​​are current values ​​that can be applied by the coil controller 20 based on, for example, the output current range of a current output IC (Integrated Circuit) of the coil controller 20. For example, when a current output limit that is an upper limit value of a current output range of the current output IC is 5A, the control information output unit 106 judges that a control current value of 5A or less is an applicable current value. When all of the control current values ​​are within the output range, the control information output unit 106 judges that all of the control current values ​​are applicable current values, and when even one of the control current values ​​is outside the current output range, the control information output unit 106 judges that all of the control current values ​​are not applicable current values.

[0077] When the control information output unit 106 determines that all of the control current values ​​are applicable current values ​​(step S303, YES), it transmits each of the control current values ​​calculated in step S302 to the coil controller 20 (step S310).

[0078] On the other hand, when the control information output unit 106 determines that none of the control current values ​​are applicable current values ​​(step S303, NO), the process proceeds to step S304. Note that, for the coils 22 whose control current values ​​are determined to be not applicable current values, the control information output unit 106 sets the coil controller 20 to apply the upper limit current value that can be applied as the control current value. This determination is made for all coils 22 selected as pickup coils.

[0079] In step S304, the control information output unit 106 searches for a coil 22 whose control current value has not reached the current output limit from among the pickup coils other than the coil 22 whose control current value has been determined to be not an applicable current value in step S303. Hereinafter, the coil 22 whose control current value has not reached the current output limit will be appropriately referred to as an application margin coil 22.

[0080] If there is no remaining application capacity coil 22 (step S304, NO), the control information output unit 106 outputs an alarm to the outside (step S309).

[0081] On the other hand, if there is an application margin coil 22 (step S304, YES), the control information output unit 106 calculates a thrust deficiency, which is the thrust to the carrier 40 that cannot be applied by the coil 22 in question because the control current value upper limit was exceeded in step S303 (step S305). The control information output unit 106 can calculate the thrust deficiency by the following equation (6). The control information output unit 106 transmits thrust deficiency information indicating the calculated thrust deficiency to the distribution amount calculator 107. Deficient thrust (idx) = (Control current value (idx) - Current output limit) x Thrust constant (idx) ... Equation (6)

[0082] For example, when the current output limit is 5 A and the control current value (idx) determined to be not an applicable current value is 6 A, the insufficient thrust is expressed by the following equation (6)'. Insufficient thrust (idx) = (6A-5A) × thrust constant (idx) …Equation (6)′

[0083] The distribution amount calculator 107 distributes the shortage thrust indicated in the shortage thrust information transmitted from the control information output device 106 to the applied reserve coils 22, regarding the applied reserve coils 22 as the coils 22 to which the shortage thrust is to be redistributed (step S306). The distribution amount calculator 107 distributes the shortage thrust indicated in the shortage thrust information transmitted from the control information output device 106 to the applied reserve coils 22 (step S306). The distribution amount calculator 107 distributes the shortage thrust to one or more applied reserve coils 22 in the same manner as when the distributed output thrust is distributed from the required thrust in step S301.

[0084] Next, the distribution amount calculator 107 updates the sum of the distributed thrust deficiency and the distributed output thrust calculated in S301 as the distributed output thrust after redistribution for the applied power surplus coil 22. The distribution amount calculator 107 outputs distributed output thrust information indicating the distributed output thrust after redistribution to the control information output device 106.

[0085] Next, in the same manner as in step S302, the control information output unit 106 recalculates the control current value for the applied reserve coil 22 using the distributed output thrust after redistribution indicated in the distributed output thrust information transmitted from the distribution amount calculator 107 (step S307).

[0086] Next, the control information output unit 106 determines whether or not the control current value calculated in step S307 is a current value that can be applied by the coil controller 20, in the same manner as in step S303 (step S308).

[0087] When the control information output unit 106 determines that the control current value calculated in step S307 is an applicable current value (step S308, YES), it transmits the control current value calculated in step S307 to the coil controller 20 (step S310).

[0088] On the other hand, if the control information output unit 106 determines that the control current value calculated in step S307 is not an applicable current value (step S308, NO), it outputs an alarm to the outside (step S309).

[0089] In this manner, in this embodiment, even if distribution of thrust that cannot be applied occurs, the thrust is redistributed to the other coils 22. Therefore, according to this embodiment, control that reduces the speed fluctuation of the carrier 40 can be more reliably performed.

[0090] Although the above description has been given of the case where the countermeasure processing is executed in the first embodiment, the countermeasure processing can also be executed in the second and third embodiments in the same manner as in this embodiment.

[0091] [Fifth embodiment] A fifth embodiment of the present invention will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a schematic diagram showing a transport device in a transport system according to this embodiment. Fig. 8 is a schematic diagram explaining the operation of the transport system according to this embodiment. Note that components similar to those in the first to fourth embodiments are given the same reference numerals, and explanations thereof will be omitted or simplified.

[0092] The transfer system 1 according to this embodiment differs from the transfer system 1 according to the first embodiment in the following points.

[0093] That is, the coil units 21 constituting the transport path 3 according to this embodiment are arranged in two parallel rows to form two coil lines 23, which is different from the configuration according to the first embodiment.

[0094] The basic configuration of the carrier 40 in this embodiment is almost the same as that in the first embodiment. The carrier 40 in this embodiment differs from the configuration in the first embodiment in the manner in which the permanent magnets 42 are attached.

[0095] Also, the control coil selector 103 according to this embodiment is different from that of the first embodiment in that it selects a pickup coil, which is a coil 22 to be controlled, for each coil line 23.

[0096] Furthermore, the distribution amount calculator 107 according to this embodiment differs from the first embodiment in that it calculates the distribution amount of the output thrust corresponding to the multiple coil lines 23 and outputs distributed output thrust information for each coil line 23.

[0097] 7 is a view of the conveying device 12 according to this embodiment as viewed from the Z direction. On the carrier 40, permanent magnets 42 are installed so as to be aligned in the X direction in two rows. The multiple permanent magnets 42 in each row are alternately magnetized and attached so that the S poles and N poles are alternately aligned in the X direction, similar to the first embodiment. The permanent magnets 42 in each row form a permanent magnet line 43. On the carrier 40, two rows of permanent magnet lines 43a, 43b are installed.

[0098] A coil line 23 is installed on the transport path 3, which is a row made up of a plurality of coil units 21 that excite the permanent magnet line 43. In the coil line 23, the plurality of coil units 21 are installed so as to be aligned in the X direction. In the transport path 3 according to this embodiment, two coil lines 23a and 23b are installed. The coil line 23a is made up of coil units 21a to 21d. The coil line 23b is made up of coil units 21e to 21h.

[0099] As shown in Fig. 7, the multiple coil units 21 that make up the transport path 3 are arranged separately on coil lines 23a and coil lines 23b. The coil lines 23a and 23b are arranged parallel to the rail 60. In the coil line 23b, adjacent coil units 21 are arranged with a gap D2 between them. In contrast, in the coil line 23a, in addition to the coil units 21 that are arranged adjacent to each other with gap D2 between them, some of the adjacent coil units 21 along the way are arranged with a gap D1 different from gap D2 between them. Gap D1 is wider than gap D2.

[0100] The carrier 40 has permanent magnet lines 43a and 43b corresponding to the coil lines 23a and 23b, respectively. The permanent magnet line 43a is disposed so as to be able to face the coil line 23a. The permanent magnet line 43b is disposed so as to be able to face the coil line 23b.

[0101] The transport device 12 may be installed, for example, in a vacuum chamber, although it is not particularly limited thereto. In this case, it is necessary to provide a structure such as a door for a person performing maintenance or the like to enter and exit the transport device 12. In order to secure a gap for the structure, it may not always be possible to install the coil units 21 in the coil line 23a and the coil line 23b at the same position in the X direction. For such reasons, there is a wide gap such as gap D1 which is wider than gap D2.

[0102] In this embodiment, since two rows of coil lines 23 are installed as described above, the control coil selector 103 selects the coil 22 facing the permanent magnet 42 as the pickup coil for each of the two rows of coil lines 23 and makes it the control target.

[0103] 8, when the center of carrier 40 is located at the center of gap D1 in the X direction, the number of pickup coils differs for coil lines 23a and 23b. That is, in coil line 23a corresponding to permanent magnet line 43a, control coil selector 103 selects coils 22c-22f of coil unit 21b and coils 22a-22d of coil unit 21c as pickup coils. On the other hand, in coil line 23b corresponding to permanent magnet line 43b, control coil selector 103 selects coils 22b-22f of coil unit 21f and coils 22a-22e of coil unit 21g as pickup coils.

[0104] For the sake of explanation, the present embodiment shows a case in which the coils 22 are arranged at equal intervals in the X direction in each coil line 23, but the intervals between the coils 22 in the X direction may vary.

[0105] The electrical angle calculator 104 calculates the thrust constant Aq for the coil 22 to be controlled that is selected as a pickup coil in each coil line 23 in the same manner as in the first embodiment.

[0106] The distribution amount calculator 107 distributes the required thrust to the coil line 23a for the permanent magnet line 43a and to the coil line 23b for the permanent magnet line 43b. For this purpose, the distribution amount calculator 107 calculates the required thrust [N] for each coil line 23, for example, as in the following formula (7). In this embodiment, the number of coil lines is two. Required thrust per coil line [N] = Output thrust [N] / Number of coil lines … Equation (7)

[0107] The distribution amount calculator 107 distributes the calculated required thrust for each coil line 23 to each coil line 23 in the same manner as in the first embodiment, and calculates a distributed output thrust for the coil 22 in that coil line 23.

[0108] In this embodiment, even if the number of coils 22 selected as pickup coils in each coil line 23 is different as described above, the required thrust for each coil line 23 is calculated and distributed to each coil line 23. Therefore, in this embodiment, even if a plurality of coil lines 23 are installed and the coil lines 23 are not disposed at the same position in the X direction or different gaps are provided between the coils 22, a desired thrust for the carrier 40 can be realized. Therefore, according to this embodiment, even if a plurality of coil lines 23 are installed, control that reduces the speed fluctuation of the carrier 40 can be performed.

[0109] In the above, the case where two coil lines 23 and two corresponding permanent magnet lines 43 are installed has been described, but the present invention is not limited to this. Three or more coil lines 23 and three or more corresponding permanent magnet lines 43 may be installed.

[0110] In addition, in the above embodiment, a case where multiple coil lines 23 and permanent magnet lines 43 are installed is described, but in the second to fourth embodiments, multiple coil lines 23 and permanent magnet lines 43 can be installed as in this embodiment.

[0111] [Sixth embodiment] A conveying system according to a sixth embodiment of the present invention will be described with reference to Figs. 9 to 10C. Fig. 9 is a block diagram of the conveying system according to this embodiment. Figs. 10A to 10C are schematic diagrams of the device according to this embodiment. Note that components similar to those in the first to fifth embodiments are given the same reference numerals and descriptions thereof will be omitted or simplified.

[0112] In the coil unit 21, a desired current may not flow through some of the coils 22 due to breakage of a part of the coils 22, disconnection of the wiring to the coils 22, heat generation of the coils 22, etc., and the coils 22 may become unusable during operation. In the unusable coils 22, an output abnormality, which is a type of failure, occurs.

[0113] The transport system 1 according to this embodiment differs from the configuration according to the first embodiment in that the transport controller 10 has an abnormality detector 108 that detects an output abnormality in the coil 22. The transport system 1 according to this embodiment also differs from the configuration according to the first embodiment in that the device information storage device 105 holds a current deviation threshold, a coil damage danger temperature threshold, and a usage permission coil temperature threshold.

[0114] In this embodiment, a case where a command current value of a predetermined threshold value or more cannot be applied to the coil 22ng in the coil 22 included in the coil unit 21c will be described as an abnormality.

[0115] For example, in the transport device 12 in a vacuum chamber, even if the output corresponding to the command value cannot be obtained due to an output abnormality of the coil 22, it is required to continue transporting the carrier 40. Furthermore, it is required to transport the carrier 40 while reducing the fluctuation of the transport speed of the carrier 40 to a specification or less. Therefore, it is preferable to detect the output abnormality of the coil 22 even during transport and distribute the thrust to maintain the thrust on the carrier 40.

[0116] As shown in Fig. 9, the transport controller 10 and the coil controller 20 are connected in the same manner as in the first embodiment. Furthermore, in this embodiment, an abnormality detector 108 is connected to the coil controller 20. Output result information indicating the output current value, the coil temperature, etc. is transmitted from the coil controller 20 to the transport controller 10. The output current value is the current value actually applied to the coil 22. The coil temperature is detected by a coil temperature detector (not shown) in the coil controller 20. The coil temperature detector is, for example, a thermocouple thermometer.

[0117] The device information storage 105 stores a current deviation threshold, a coil damage danger temperature threshold, and a usage permission coil temperature threshold.

[0118] Fig. 10A shows a schematic configuration of the transport device 12. Coil 22ng represents the coil 22 in which an output abnormality has occurred. Fig. 10B shows a control state when the coil 22 is normal. Fig. 10C shows a control state when an abnormality has occurred in the coil 22ng.

[0119] The anomaly detector 108 determines whether or not the coil 22 is usable based on the output result information transmitted from the coil controller 20. When the anomaly detector 108 determines that the coil 22 is not usable, it outputs abnormal coil information identifying the coil 22 to the control coil selector 103. The anomaly detector 108 determines whether or not the coil 22 is usable by the following method. In this way, the anomaly detector 108 functions as an anomaly detection unit that detects output abnormalities in the coil 22.

[0120] First, the abnormality detector 108 calculates the output current deviation, which is the difference between the output current value indicated in the output result information transmitted from the coil controller 20 and the control current value to each coil 22 calculated by the control information output device 106, using the following equation (8). Output current deviation = control current value - output current value ... formula (8)

[0121] Next, the anomaly detector 108 compares the calculated output current deviation with the current deviation threshold value stored in the device information storage 105 in absolute value. As a result, if the output current deviation is greater than the current deviation threshold value, the anomaly detector 108 determines that the coil 22 is not usable, and stores abnormal coil information identifying the coil 22 as an output abnormality of the coil 22. The timing of storing the abnormal coil information is, for example, when the output current deviation during operation is continuously monitored and is determined to be greater than the current deviation threshold value. Also, when no control is being performed on the carrier 40, a diagnostic current value may be passed to determine whether the coil 22 is usable.

[0122] The abnormality detector 108 outputs abnormal coil information that identifies the coil 22 determined to be the coil 22 with an output abnormality to the control coil selector 103 .

[0123] Similarly, when the coil temperature indicated in the output result information exceeds the coil damage risk temperature threshold, the anomaly detector 108 stores the coil 22 with the abnormal temperature in the abnormal coil information as a coil 22ng with an output abnormality. In this case, the anomaly detector 108 stores the coil 22ng stored in the abnormal coil information as a coil 22ng with an output abnormality in the abnormal coil information until the coil temperature falls below the usage permission coil temperature threshold, and releases the storage of the coil in the abnormal coil information when the coil temperature falls below the usage permission coil temperature threshold. The coil 22 that has been released from storage in the abnormal coil information is again treated as a coil selected as a pickup coil.

[0124] For example, the coil damage danger temperature threshold is set to 120 degrees, and the usable coil temperature threshold is set to 60 degrees. In this case, once the coil temperature exceeds 120 degrees and is held in the abnormal coil information as a coil 22ng with an output abnormality, it is held in the abnormal coil information until the coil temperature falls to 60 degrees.

[0125] In addition, the abnormality detector 108 functions as an alarm unit, and when it detects a coil 22ng with an output abnormality as described above, it can output an alarm to the outside to notify the user that an output abnormality, which is a type of malfunction, has occurred.

[0126] The control coil selector 103 compares the coil 22 selected as the pickup coil to be controlled with the coil 22ng specified in the abnormal coil information. If the coil 22ng is present in the pickup coils, the control coil selector 103 excludes the coil 22ng from the pickup coils.

[0127] In this manner, in this embodiment, the coil 22ng with an output abnormality is not selected as a pickup coil in the subsequent thrust distribution process, so that thrust distribution can be performed in accordance with the actual state of the coil 22 to determine the control current value.

[0128] FIG. 10B shows a normal state when there is no coil 22ng with an output abnormality, and FIG. 10C shows an abnormal state when there is a coil 22ng with an output abnormality.

[0129] In FIG. 10B, eight coils 22 are selected as pickup coils to be controlled, and thrust constants Aq0 to Aq7 are used to calculate thrust distribution and control current values ​​in the same manner as in the first embodiment.

[0130] 10C, coil 22ng is determined to be the coil 22 in which an output abnormality has occurred. Therefore, in this case, seven coils 22 are selected as pickup coils to be controlled, and thrust distribution and control current values ​​are calculated in the same manner as in the first embodiment, using thrust constants Aq0 to Aq7 other than thrust constant Aq5 corresponding to coil 22ng.

[0131] In this manner, in this embodiment, the coils 22 that do not contribute to the thrust due to the occurrence of an output abnormality are identified during operation and incorporated into the control calculation, thereby realizing a desired thrust for the carrier 40. Therefore, according to this embodiment, even if there is a coil 22ng with an output abnormality, it is possible to perform control that suppresses the speed fluctuation of the carrier 40.

[0132] In the above description, the determination of the coil having an output abnormality is performed by the abnormality detector 108 in the transport controller 10, but this is not limited to the above. For example, the coil controller 20 may detect and determine whether the coil 22 has an output abnormality.

[0133] Furthermore, in the above embodiment, the case where the determination of the coil having an abnormal output is performed has been described. However, in the second to fourth embodiments, the same countermeasure processing as in this embodiment can also be executed.

[0134] In addition, although the above description has been given of the case where there is one coil line 23, the present invention is not limited to this. The control of the multiple coil lines 23 described in the fifth embodiment may be performed in the same manner as in this embodiment.

[0135] [Seventh embodiment] A conveying system according to a seventh embodiment of the present invention will be described with reference to Figs. 11 and 12. Fig. 11 is a schematic configuration diagram showing a running system in the conveying system according to this embodiment. Fig. 12 is a block diagram showing the conveying system according to this embodiment. Note that components similar to those in the first to sixth embodiments are given the same reference numerals and descriptions thereof will be omitted or simplified.

[0136] The conveying system 1 of this embodiment differs from the configuration of the first embodiment in that it has an operation system 2 that includes multiple control systems 13 similar to those of the first embodiment and an operation controller 11 communicatively connected to the multiple conveying controllers 10.

[0137] For example, in a transfer system 1 installed in a large-scale vacuum device, multiple vacuum chambers are connected to form a transfer path 3. In such a case, one control system 13 controls one or multiple carriers 40 for the transfer path 3 of one vacuum chamber, but control must be performed by transferring between multiple control systems 13.

[0138] In this embodiment, in the control by the multiple independent control systems 13 where transfers occur as described above, the speed fluctuation of the carrier 40 is reduced as follows.

[0139] Fig. 11 is a schematic configuration diagram showing the operation system 2 in the conveyance system 1 according to this embodiment. As shown in Fig. 11, the operation system 2 has an operation controller 11 and a plurality of control systems 13. Each control system 13 has the same components as those in the first embodiment, as shown in the upper part of Fig. 11. The operation controller 11 functions as a host control unit that controls the plurality of control systems 13.

[0140] 11, a plurality of control systems 13a to 13n are successively arranged in the operation system 2. The operation controller 11 is communicably connected to the transport controllers 10 of the respective control systems 13a to 13n.

[0141] FIG. 12 shows a case where the carrier 40 is transferring from the control system 13a to the control system 13b.

[0142] When the carrier 40 is transferred from the control system 13a to the control system 13b, it is necessary to distribute the thrusts that are to be output by the control systems 13a and 13b. Therefore, in this embodiment, the required thrusts are distributed in the following procedure.

[0143] The operation controller 11 preliminarily stores the total length of the carrier 40 in the X direction and the system control range of the control system 13. The system control range is the range in the X direction over which the control system 13 is responsible for controlling the carrier 40. The operation controller 11 also acquires the current position of the carrier 40 from each control system 13. The operation controller 11 also acquires distributed output thrust information output by each control system 13 from each control system 13.

[0144] 12, the origin of the absolute coordinates of the position in the X direction in the control system 13a is set to Sys1c. The origin Sys1c is set to the absolute position of 0, and a positive value is taken as the absolute position toward the control system 13b side. In addition, in the absolute coordinates of the position of the control system 13a, the system control range in charge of controlling the carrier 40 is represented as SysL1.

[0145] 12, the center position of the carrier 40 is CaO. In the absolute coordinate system of the control system 13a in the X direction, the current position of the carrier 40 is CaPos. Also, the total length of the carrier 40 in the X direction is Lc.

[0146] The flight controller 11 has a distributed thrust calculator 109. The distributed thrust calculator 109 distributes the required thrust to the control system 13a and the control system 13b. The required thrust calculated in the control system 13 is input to the distributed thrust calculator 109 from the control system 13.

[0147] The distributed thrust calculator 109 calculates a transition thrust ratio coefficient from the overall length Lc of the carrier 40, the system control range SysL1, and the current position of the carrier 40 using the following equations (9) to (11). The transition thrust ratio coefficient is a coefficient for distributing the required thrust to the control system 13a and the control system 13b. The transition thrust ratio coefficient for the control system 13a is set to ka, and the transition thrust ratio coefficient for the control system 13b is set to kb. The current position CaPos of the carrier 40 used in the following equations is the current position of the carrier 40 obtained from the control system 13a.

[0148] Prior to calculating the transit thrust proportion coefficient, the distribution thrust calculator 109 calculates the intra-system control range length La by the following equation (9). System control range length La = System control range SysL1 - Current position CaPos + Carrier total length Lc × (1 / 2) ... Equation (9)

[0149] The distributed thrust calculator 109 calculates the transfer thrust ratio coefficients ka and kb by the following equations (10) and (11), respectively, using the intra-system control range length La. Transit thrust ratio coefficient ka = control range length within the system La / total carrier length Lc … Equation (10) Transition thrust rate coefficient kb = 1 - Transition thrust rate coefficient ka ... Equation (11)

[0150] The distributed thrust calculator 109 distributes the required thrust to the control systems 13a and 13b using the calculated transition thrust ratio coefficients ka and kb. The required thrust to be distributed is that calculated by the control system 13a. The distributed thrust calculator 109 distributes the product of the transition thrust ratio coefficient ka and the required thrust as a first required thrust to the control system 13a. The distributed thrust calculator 109 also distributes the product of the transition thrust ratio coefficient ka and the required thrust as a second required thrust to the control system 13b.

[0151] For example, consider a case where the required thrust calculated by the control system 13a is 1000 N, the transit thrust ratio coefficient ka is 0.6, and the transit thrust ratio coefficient kb is 0.4. In this case, the first required thrust distributed to the control system 13a is 600 N, and the distributed thrust to the control system 13b is 400 N.

[0152] The distributed first and second required thrusts are updated with respect to the output thrust input to the distribution amount calculator 107, and are treated as required thrusts for which control current values ​​should be calculated in the control systems 13a and 13b, respectively, in the same manner as in the first embodiment.

[0153] Thus, in this embodiment, even when the transport controller 10 is changed, each transport controller 10 can realize a desired thrust force for the carrier 40. Therefore, according to this embodiment, even when the transport controller 10 is changed, it is possible to perform control that reduces the speed fluctuation of the carrier 40.

[0154] In the above, the case where the operation controller 11 has the distributed thrust calculator 109 has been described, but the present invention is not limited to this. The transport controller 10 may have the distributed thrust calculator 109. In this case, the transport controller 10b and the transport controller 10b are connected to be able to communicate with each other, and the required thrust can be distributed to either the side where the carrier 40 is discharged or the side where the carrier 40 is received, and the distribution result can be input to the other side.

[0155] In addition, while the above description has been given of the first embodiment in which the operating system 2 includes multiple control systems 13, the second to sixth embodiments can also be configured to include an operating system 2 that includes multiple control systems 13 in the same manner as described above.

[0156] [Modified embodiment] The present invention is not limited to the above-described embodiment, and various modifications are possible. The conveying system according to the present invention can be used as a conveying system in a manufacturing system for manufacturing articles such as electronic devices, which conveys a workpiece together with a movable element to the working area of ​​each process device, such as a machine tool, which performs each work process on the workpiece, which is a movable article. The process device which performs the work process may be any device, such as a device which assembles parts on the workpiece, or a device which performs painting. The articles to be manufactured are not limited to specific ones, and may be any parts. In this way, the conveying system according to the present invention can be used to convey the workpiece to the working area, and the work process is performed on the workpiece conveyed to the working area to manufacture the article.

[0157] As described above, in the transport system according to the present invention, even if the coils are not arranged at equal intervals, control according to the position of the carrier and the result of the output state of the coils can be performed to reduce speed fluctuations. Also, in the transport system according to the present invention, even if an output abnormality occurs in the coil due to a break in the wire or a temperature change, control according to the position of the carrier and the result of the output state of the coils can be performed to reduce speed fluctuations. [Explanation of symbols]

[0158] 1. Transport system 2. Operation System 3. Transport Path 10 Transport Controller 11 Operation Controller 12. Conveyor 13. Control System 14 Process equipment 20 Coil Controller 21 Coil unit 22 Coil 23 Coil Line 30 Sensor Controller 31 Encoder 40 Career 41 Scale 42 Permanent Magnets 43 Permanent Magnet Line 44 Lola 60 Rail 61 Rail support part 100 Position command 101 Control deviation calculator 102 Position Controller 103 Control coil selector 104 Electrical angle calculator 105 Device information storage 106 Control information output device 107 Distribution amount calculator 108 Anomaly Detector 109 Distributed thrust calculator 110 Location Selector

Claims

1. a conveying path having a plurality of coils arranged at a first distance and a second distance different from the first distance in a predetermined direction; a position detection unit that detects the position of a mover having a plurality of magnet portions arranged along the predetermined direction; a control unit that controls the movement of the mover by supplying current to the plurality of coils; having The control unit is selecting at least one coil from the plurality of coils to control the movement of the mover in response to a position of the mover; Calculating a thrust constant of the at least one selected coil based on a position of the at least one selected coil and a position of the magnet portion; Distributing a thrust force against the mover to the at least one selected coil; determining a current value for the at least one selected coil based on the thrust constant and the distributed thrust; A transport system comprising:

2. The control unit distributes thrust to the mover based on the number of the selected coils or the ratio of the thrust constants of the selected coils.

2. The transport system according to claim 1.

3. The control unit determines the current value of the selected coil based on the thrust constant corrected by the thrust transmission efficiency.

3. The transport system according to claim 1 or 2.

4. The control unit selects a plurality of coils, and when a current value of one of the selected coils cannot be applied, distributes a shortage of thrust for the mover to the other coils among the selected coils that have a surplus of power to be applied.

4. The transport system according to claim 1, wherein the transport system is a transport device.

5. The coils are arranged in a plurality of rows along the predetermined direction, The distance between the coils is different in each of the plurality of rows.

5. The transport system according to claim 1, wherein the transport system is a conveyor.

6. The number of at least one coil selected by the control unit to control the movement of the mover is different for each of the plurality of rows.

6. The transport system according to claim 5.

7. The control unit excludes the abnormal coil from the selected coils when an abnormality is detected in the coil.

7. The transport system according to claim 1, wherein the transport system is a transport device.

8. The abnormal coil excluded from the selected coils is a coil whose temperature exceeds a predetermined temperature threshold, The control unit treats the abnormal coil as the selected coil when the temperature of the abnormal coil becomes equal to or lower than the predetermined temperature threshold.

8. The transport system according to claim 7.

9. A storage unit for storing the position of the coil and the position of the magnet unit 9. The transport system according to claim 1, wherein the transport system is a conveyor.

10. The storage unit stores the position of the magnet unit for each of the movers.

10. The transport system according to claim 9.

11. A plurality of the control units; A host control unit that controls the plurality of control units, The host control unit distributes a thrust force applied to the mover to the first control unit and the second control unit when the mover is transferred from a first control unit to a second control unit among the plurality of control units.

11. The transport system according to claim 1 .

12. A control system for controlling a conveying system having a conveying path having a plurality of coils arranged in a predetermined direction at a first distance and a second distance different from the first distance, and a position detection unit that detects a position of a mover having a plurality of magnet portions arranged along the predetermined direction, a selection means for selecting at least one coil from the plurality of coils to control movement of the mover in accordance with a position of the mover; a calculation means for calculating a thrust constant of the at least one selected coil based on a position of the at least one selected coil and a position of the magnet portion; a distribution means for distributing a thrust force acting on the mover to the at least one selected coil; a determining means for determining a current value of the at least one selected coil based on the thrust constant and the distributed thrust; a control means for controlling the movement of the mover by supplying a current having the determined current value to the at least one selected coil; A control system comprising:

13. A method for controlling a conveying system having a conveying path including a plurality of coils arranged in a predetermined direction at a first distance and a second distance different from the first distance, and a position detection unit that detects a position of a mover having a plurality of magnet portions arranged along the predetermined direction, comprising: selecting at least one coil from the plurality of coils to control the movement of the mover in response to a position of the mover; Calculating a thrust constant from the position of the at least one selected coil and the position of the magnet portion; Distributing a thrust force against the mover to the at least one selected coil; determining a current value for the at least one selected coil based on the thrust constant and the distributed thrust; A current having the determined current value is supplied to the at least one selected coil, thereby controlling the movement of the mover. A control method comprising:

14. A transport system according to any one of claims 1 to 11, a process device that processes the workpiece transported by the mover; A processing system comprising:

15. A method for manufacturing an article using the processing system according to claim 14, transporting the workpiece by the mover; performing the processing on the workpiece transported by the mover by the processing device; A method for producing an article, comprising the steps of:

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