Linear transport system, control method for linear transport system, and control device for linear transport system

Abstract

To easily achieve cooperative control by a plurality of coil sets for the same movable element.SOLUTION: A linear transport system 1 includes a stator 3 having a plurality of coil sets 17 each including a three phase coil, a mover 5 having a magnet 21 and moving along the stator 3, and a multi-axis amplifier 11 that controls the movement of the mover 5 by dividing the plurality of coil sets 17 into a main control axis to which power is supplied by position, speed, or torque control based on a position, speed, or torque command and a sub-axis to which power is supplied by torque control based on a torque command output by the position, speed, or torque control on the main control axis.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The disclosed embodiments relate to a linear transport system, a control method for a linear transport system, and a control device for a linear transport system. [Background technology]

[0002] Patent Document 1 describes a linear conveyance system having a stator equipped with multiple coils, multiple movers equipped with magnets and moving along the stator, a scale provided on the movers, and multiple sensor heads arranged at predetermined intervals along the stator to detect the scale. The stator has multiple coil sets each consisting of a U-phase coil, a V-phase coil, and a W-phase coil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7316554 Summary of the Invention [Problem to be solved by the invention]

[0004] In the linear transport system, coordinated control is performed by a plurality of coil sets for the same mover, and there has been a demand for a linear transport system that can more easily realize such coordinated control.

[0005] The disclosed embodiments have been made in consideration of these problems, and aim to provide a linear conveying system, a control method for a linear conveying system, and a control device for a linear conveying system that can easily achieve coordinated control using multiple coil sets for the same mover. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present invention, a linear conveying system is provided which includes a stator having a plurality of coil sets each consisting of a three-phase coil, a mover having a magnet and moving along the stator, and a control device which controls the movement of the mover by dividing the plurality of coil sets into a first coil set which supplies power by a first control based on a first command, and a second coil set which supplies power by a second control based on a second command output by the first control.

[0007] According to another aspect of the present invention, a control method for a linear conveying system having a stator having a plurality of coil sets consisting of three-phase coils, and a mover having a magnet and moving along the stator, is applied, which controls the movement of the mover by dividing the plurality of coil sets into a first coil set that is powered by a first control based on a first command, and a second coil set that is powered by a second control based on a second command output by the first control.

[0008] According to another aspect of the present invention, there is provided a control device for a linear conveying system having a stator having a plurality of coil sets each consisting of a three-phase coil, and a mover having a magnet and moving along the stator, wherein the control device controls the movement of the mover by sequentially switching the coil sets between position, speed, or torque control, or torque control based on a torque command output by any of the position, speed, or torque control. [Effects of the Invention]

[0009] According to the linear transport system etc. of the present invention, cooperative control by a plurality of coil sets for the same mover can be easily realized. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram conceptually illustrating an example of the overall configuration of a linear transport system according to an embodiment. [Figure 2]FIG. 2 is a diagram conceptually illustrating a part of an example of the configuration of a control system of the linear transport system according to the embodiment. [Figure 3] FIG. 2 is a block diagram illustrating an example of a functional configuration of a control unit of a multi-axis amplifier. [Figure 4] 10A and 10B are explanatory diagrams showing specific examples of a method for calculating the center position of a mover by a calculation unit and a method for estimating detection data by an estimation unit. [Figure 5] 10A and 10B are explanatory diagrams showing a specific example of switching of the control mode by the discriminator when the mover moves in the forward direction. [Figure 6] 10A and 10B are explanatory diagrams showing a specific example of switching of the control mode by the discriminator when the mover moves in the negative direction. [Figure 7] 10 is a conceptual diagram showing an example of a sensor configuration of a stator and a magnet configuration of a mover in a modified example in which an identification magnet is provided on the mover. FIG. [Figure 8] FIG. 2 is a block diagram illustrating an example of the hardware configuration of a multi-axis amplifier. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described with reference to the drawings.

[0012] <1. Overall configuration of the linear transport system> An example of the overall configuration of a linear conveyance system according to an embodiment will be described with reference to Figures 1 and 2. Figure 1 is a diagram conceptually showing an example of the overall configuration of a linear conveyance system according to an embodiment, and Figure 2 is a diagram conceptually showing an extracted portion of an example of the configuration of a control system of the linear conveyance system according to an embodiment.

[0013] As shown in FIG. 1, the linear conveyance system 1 has a stator 3. The stator 3 is arranged in a loop shape, and multiple movers 5 are arranged on the stator 3. Each mover 5 moves along the stator 3 to convey the workpiece W. The stator 3 has multiple coil sets consisting of three-phase coils, and each mover 5 has a magnet. In other words, the linear conveyance system 1 is a so-called moving magnet type. Each mover 5 may have the same length in the moving direction, or multiple types of movers with different lengths in the moving direction may be included. Around the stator 3, for example, a processing device R1 that processes and assembles the workpiece W, a carry-in device R2 that carries in the workpiece W, and an unloading device R3 that carries out the workpiece W are arranged. The linear conveyance system 1 conveys the workpiece W by, for example, moving each mover 5 in the direction of arrow 7 in FIG. 1. Note that the mover 5 may move in the direction opposite to the arrow 7, or multiple movers 5 may move simultaneously in different directions.

[0014] As shown in Fig. 2, the linear conveyance system 1 includes a multi-axis amplifier 11, a linear controller 13, and a travel controller 15. Fig. 2 illustrates only a portion of the stator 3, but other portions of the stator 3 have the same configuration.

[0015] The multi-axis amplifier 11 (an example of a control device) controls the energization of coil sets in a portion of the stator 3. In the example shown in FIG. 2 , when three coils, for example, a U-phase coil 17U, a V-phase coil 17V, and a W-phase coil 17W provided on the stator 3, are defined as one coil set 17, the multi-axis amplifier 11 supplies power to, for example, two coil sets 17. The multi-axis amplifier 11 independently controls the energization of each of the two coil sets 17, thereby controlling the position, speed, or torque of the mover 5. For example, one multi-axis amplifier 11 is installed for each of the two coil sets 17. The multiple multi-axis amplifiers 11 that energize the coil sets 17 belonging to the same stator 3 are connected to each other via a communication cable 19, and are capable of transmitting and receiving data via, for example, SPI (Serial Peripheral Interface) communication or the like.

[0016] As shown in FIG. 2, each mover 5 has a magnet 21, which is a permanent magnet, and a scale 23. The scale 23 is provided with a mover identification means for identifying each mover 5 and a scale for detecting the mechanical coordinate position of each mover 5. As shown in FIG. 2, multiple sensor heads 25 (an example of a sensor) that detect the scale 23 are arranged for each coil set 17 along the stator 3. That is, one sensor head 25 is arranged corresponding to one coil set 17. The sensor head 25 is arranged approximately at the center of the corresponding coil set 17. Note that the sensor head 25 may be arranged at a position other than the center of the coil set 17. The sensor head 25 reads the scale 23 of the opposing mover 5 to detect the mover identification means and the mechanical coordinate position. Two sensor heads 25 corresponding to the two coil sets 17 to be controlled are connected to each multi-axis amplifier 11. Each multi-axis amplifier 11 receives detection data from the two sensor heads 25. Each multi-axis amplifier 11 shares the detection data of the sensor head 25 and the like with the adjacent multi-axis amplifier 11 (the multi-axis amplifier 11 corresponding to the front and rear in the movement direction) via the communication cable 19. This allows smooth switching of the control of the multi-axis amplifier 11 in accordance with the movement of the mover 5.

[0017] The linear controller 13 is connected to a plurality of multi-axis amplifiers 11 corresponding to a common stator 3 via a communication cable 19. The linear controller 13 manages the positions of a plurality of movers 5 located on the loop of the stator 3. For example, each mover 5 is controlled so that two or more movers 5 are not located on one coil set 17. The linear conveyance system 1 has a plurality of linear controllers 13. The linear controller 13 transmits a position command, received from, for example, the operation controller 15, to each multi-axis amplifier 11 to specify the position of each mover 5 on the loop of the stator 3. The linear controller 13 may also transmit a speed command or a torque command to each multi-axis amplifier 11.

[0018] The motion controller 15 is connected to the multiple linear controllers 13 via a communication cable 19. The motion controller 15 manages the positions of the multiple movers 5 located on the loop of the stator 3, i.e., all of the movers 5 provided in the linear conveyance system 1. The motion controller 15 sends position commands to each linear controller 13 to specify the position of each mover 5 on the loop of the stator 3.

[0019] The linear controller 13 and the motion controller 15 are control devices having, for example, a processing unit (CPU), a recording device, an input device, etc. As the linear controller 13 and the motion controller 15, for example, a general-purpose computer (PC), a motion controller, a programmable logic controller (PLC), etc. may be used.

[0020] The configuration of the linear transport system 1 described above is an example and is not limited to the above. For example, the stator 3 may be installed horizontally, vertically, or tilted at a predetermined angle relative to the horizontal. The number of stators 3 is not limited to one, but may be multiple. The multi-axis amplifier 11 does not need to supply power to two coil sets 17, but may supply power to three or more coil sets 17. A single-axis amplifier may also be used to supply power to one coil set 17.

[0021] <2. Functional configuration of the multi-axis amplifier control unit> An example of the functional configuration of the control unit of the multi-axis amplifier 11 will be described with reference to Fig. 3. The multi-axis amplifier 11 has a control unit having, for example, a processing unit (CPU), a recording device, etc., and a power supply unit (for example, an inverter unit, a PWM control circuit, etc.) that supplies power to the coil set 17 of the stator 3. Fig. 3 is a block diagram showing an example of the functional configuration of the control unit of the multi-axis amplifier 11, with the power supply unit not shown.

[0022] In this embodiment, the length of the mover 5 in the movement direction is longer than that of the coil sets 17 of the stator 3, and the mover 5 is arranged to straddle multiple coil sets 17. Therefore, the multi-axis amplifier 11 controls the movement of the mover 5 by using multiple coil sets 17 in coordination with each other. In this embodiment, the multi-axis amplifier 11 controls the movement of the mover 5 by dividing the multiple coil sets 17 into a first coil set that is powered by position, velocity, or torque control (an example of first control) based on a position, velocity, or torque command (an example of a first command) from the linear controller 13, and a second coil set that is powered by torque control (an example of second control) based on a torque command (an example of a second command) output by the position, velocity, or torque control. In this case, the multi-axis amplifier 11 controls the movement of the mover 5 by sequentially switching the coil set 17, at least a portion of which faces the mover 5, between the first coil set and the second coil set. That is, the multi-axis amplifier 11 controls the movement of the mover 5 by sequentially switching the coil set 17 between position, speed, and torque control based on a position, speed, or torque command, or between torque control based on a torque command output by the position, speed, or torque control. Note that in the embodiments, the first coil set is referred to as the "main control axis" and the second coil set is referred to as the "sub-axis" as appropriate. An example of the functional configuration of the multi-axis amplifier 11 for realizing the above control will be described below.

[0023] 3, the multi-axis amplifier 11 has a recording unit 27, a calculation unit 29, a discrimination unit 31, a sharing unit 33, an estimation unit 35, and a motor control unit 37. The motor control unit 37 controls the energization of each of the two coil sets 17, and controls a linear motor constituted by the two coil sets 17 and the mover 5. The motor control unit 37 has a position control unit 39, a speed control unit 41, and a current control unit 43. The motor control unit 37 has two control modes: upper command control (position, speed, or torque control) for the main control axis, and torque assist control for the sub-axis, and switches the control mode for each coil set 17.

[0024] The motor control unit 37 performs higher-level command control (position, speed, or torque control) on the coil set 17 of the main control axis as follows. The position control unit 39 generates a speed command based on the position deviation between the position command from the linear controller 13 and the mechanical coordinate position of the mover 5 (calculated by the calculation unit 29) based on the detection data of the sensor head 25. The speed control unit 41 generates a torque command based on the speed deviation between the speed command generated by the position control unit 39 or the speed command from the linear controller 13 and the mover speed based on the detection data of the sensor head 25. The current control unit 43 converts the torque command generated by the speed control unit 41 into a current command, generates a voltage command based on the current command and detection data from a current sensor that detects the current supplied to the coil set 17, and generates a control signal (e.g., a PWM signal) based on the voltage command. The control signal is output to an inverter unit (not shown). The inverter unit converts DC power to AC power based on the control signal and supplies it to the coil set 17.

[0025] The motor control unit 37 performs torque assist control on the sub-axis coil set 17 as follows: In higher-level command control (position, speed, or torque control) performed on the main control axis coil set 17, which controls the common mover 5, the motor control unit 37 acquires a torque command output by either position, speed, or torque control via intra-amplifier or inter-amplifier communication (SPI communication, etc.). The current control unit 43 converts the acquired torque command into a current command, generates a voltage command based on the current command and detection data from a current sensor, and supplies power to the coil set 17 based on the voltage command.

[0026] The recording unit 27 records, as a parameter for each sensor head 25, the machine coordinate offset, which is a cumulative value accumulated from the sensor head 25 whose placement interval is set as the origin. The recording unit 27 may be, for example, a nonvolatile memory such as an EEPROM or a recording device such as a hard disk. As described above, the sensor heads 25 are each placed at approximately the center of the coil set 17, so the placement interval of the sensor heads 25 can also be referred to as the placement interval of the coil sets 17. The recording unit 27 may record the parameters for two sensor heads 25 connected to the multi-axis amplifier 11 to which the recording unit 27 belongs, or may record the parameters for all sensor heads 25 placed on a common stator 3. The recording unit 27 may also be provided external to the multi-axis amplifier 11, for example, in the linear controller 13, the operation controller 15, the sensor head 25, or another external recording device. In this case, the multi-axis amplifier 11 simply acquires necessary information from the externally installed recording unit 27.

[0027] The calculation unit 29 calculates the reference position of the mover 5 based on the detection data of the sensor head 25 that detected the scale 23. In this embodiment, the reference position is the center position in the movement direction of the mover 5. That is, the calculation unit 29 calculates the center position of the mover 5 based on the detection data of the sensor head 25 that detected the scale 23, the machine coordinate offset amount that is a parameter set in the sensor head 25 that detected the scale 23, and the length of the mover 5 in the movement direction. The method of calculating the center position will be described in detail later. Note that the reference position of the mover 5 may be other than the center position, for example, the tip position in the movement direction.

[0028] The discriminator 31 determines whether to switch the coil set 17 facing the mover 5 to a main control axis or a sub-axis based on the center position calculated by the calculator 29. In other words, the discriminator 31 determines whether to switch the control mode of the coil set 17 facing the mover 5 to a higher-level command control (one of position, speed, or torque control) or a torque assist control based on the center position calculated by the calculator 29. In this embodiment, the discriminator 31 switches the second coil set 17 from the front in the moving direction of the mover 5, of the coil sets 17 at least a portion of which faces the mover 5, to a main control axis that performs higher-level command control (one of position, speed, or torque control), and switches the coil sets 17 other than the second one to a sub-axis that performs torque assist control. The details of switching the control mode will be described later.

[0029] Note that a coil set 17 other than the second from the front may be used as the main control shaft. For example, if the length of the mover 5 is equal to or longer than three coil sets 17, the entire coil sets 17 from the third from the front will also face the mover 5. In such a case, the coil sets 17 from the third from the front may be used as the main control shaft.

[0030] The sharing unit 33 shares at least one of the detection data of the sensor head 25 corresponding to the coil set 17 of the main control axis and the detection data of the sensor head 25 corresponding to the coil set 17 of the sub-axis among the multiple multi-axis amplifiers 11 through inter-amplifier communication (SPI communication, etc.). The multiple multi-axis amplifiers 11 that share the detection data are multi-axis amplifiers 11 that include, as control targets, at least a portion of the coil set 17 that faces the mover 5.

[0031] If there is a coil set 17 whose sensor head 25 does not detect the scale 23 among the coil sets 17 at least a portion of which faces the mover 5, the estimation unit 35 estimates the detection data of the sensor head 25 of that coil set 17 based on the detection data of the sensor head 25 of the coil set 17 adjacent to at least one of the positive side and negative side in the moving direction of the mover 5, which is shared by the sharing unit 33. The method of estimating the detection data will be described in detail later.

[0032] The combination of the scale 23 and the sensor head 25 may be either an incremental type or an absolute type.

[0033] The processes performed by the recording unit 27, calculation unit 29, discrimination unit 31, sharing unit 33, estimation unit 35, motor control unit 37, etc. described above are not limited to the examples of the division of processes. For example, the processes may be performed by a smaller number of processing units (e.g., one processing unit) or by more subdivided processing units. In the multi-axis amplifier 11, only the parts that supply power to the coil set 17 (e.g., an inverter unit, a PWM control circuit, etc.) may be implemented by actual devices, and the other functions of each of the above processing units may be implemented by a program executed by a CPU 901 (see FIG. 8 ), which will be described later. Some or all of the functions of each of the above processing units may be implemented by actual devices such as ASICs, FPGAs, or other electric circuits. The functions of each of the above processing units do not necessarily have to be performed only by the multi-axis amplifier 11, and some or all of them may be performed by the linear controller 13 or the operation controller 15.

[0034] <3. Specific examples of methods for calculating the center position of the mover and estimating detection data> Specific examples of a method for calculating the center position of the mover 5 by the calculation unit 29 and a method for estimating the detection data by the estimation unit 35 will be described with reference to FIG.

[0035] In the example shown in FIG. 4 , the stator 3 has m coil sets 17, numbered No. 1 to No. m, with the coil set 17 corresponding to the sensor head 25 set at the origin position designated No. 1. Hereinafter, the sensor head 25 corresponding to No. 1 coil set 17 will be simply referred to as the “No. 1 sensor head 25.” The mechanical coordinate offset is a cumulative value obtained by accumulating the arrangement interval Ls of the sensor heads 25 from the sensor head 25 set at the origin position. The value is 0 for No. 1 sensor head 25 and Ls × (m-1) for No. m sensor head 25. In this embodiment, the movement direction of the mover 5 is a positive direction when the mechanical coordinate offset increases, and a negative direction when the mechanical coordinate offset decreases. In the example shown in FIG. 4 , the movement direction of the mover 5 is a positive direction. The arrangement interval Ls of the sensor heads 25 is also the arrangement interval of the coil sets 17. Also, in FIG. 4 , the length Lm of the mover 5 is, for example, twice the length of the coil sets 17, i.e., 2 × Ls.

[0036] 4, three coil sets 17, No. 1 to No. 3, are coil sets at least partially facing the mover 5. Of these, the sensor heads 25 of No. 2 and No. 3 face the scale 23 and are therefore capable of detection, but the sensor head 25 of No. 1 does not face the scale 23 and is therefore unable to detect it. The calculation unit 29 calculates the center position Pc of the mover 5 using Equation 1 based on the detection data Fb of the sensor head 25 that detected the scale 23, the mechanical coordinate offset amount of the sensor head 25, and half the length of the mover 5 in the movement direction (Lm / 2). Center position (Pc) = Sensor head detection data (Fb) + Machine coordinate offset amount - Half the length of the mover (Lm / 2) (Equation 1)

[0037] Applying Equation 1 to the No. 2 sensor head 25 yields Equation 2. Fb2 is the detection data of the No. 2 sensor head 25. Pc=Fb2+Ls-(Lm / 2)...(Formula 2) Applying Equation 1 to the No. 3 sensor head 25 yields Equation 3. Fb3 is the detection data of the No. 3 sensor head 25. Pc=Fb3+(Ls×2)-(Lm / 2)...(Formula 3)

[0038] The estimation unit 35 also estimates the detection data Fb1 of the No. 1 sensor head 25 using Equation 4 based on the detection data Fb2 of the No. 2 sensor head 25 adjacent to the sensor head 25 on the positive side, which is shared by the sharing unit 33. Fb1=Fb2+Ls...(Formula 4) The calculation unit 29 calculates the center position Pc of the mover 5 using Equation 5 based on the detection data Fb1 estimated by the estimation unit . Pc=Fb1+(0)-(Lm / 2) =Fb2+Ls+(0)-(Lm / 2) (Formula 5)

[0039] The estimation unit 35 also estimates the detection data Fb4 of the No. 4 sensor head 25 using Equation 6 based on the detection data Fb3 of the No. 3 sensor head 25 that is adjacent to the sensor head 25 on the negative side and that is shared by the sharing unit 33. Fb4=Fb3-Ls...(Formula 6) The calculation unit 29 calculates the center position Pc of the mover 5 using Equation 7 based on the detection data Fb4 estimated by the estimation unit . Pc = Fb4 + (Ls × 3) - (Lm / 2) =Fb3-Ls+(Ls×3)-(Lm / 2)...(Formula 7)

[0040] Since Fb2=Fb3+Ls, the above formulas 2, 3, 5, and 7 all have the same value. Therefore, the center position Pc is calculated as the same position regardless of the detection data of any of the sensor heads 25, No. 1 to No. 4.

[0041] <4. Specific examples of control mode switching by the discrimination unit> 5 and 6, a specific example of switching of the control mode by the discriminator 31 will be described. In Fig. 5 and Fig. 6, for example, two movers 5A and 5B are arranged. The length of the mover 5A in the movement direction is, for example, the length of two coil sets 17, and the length of the mover 5B in the movement direction is, for example, the length of three coil sets 17.

[0042] Figure 5 shows the case where movers 5A and 5B move in the positive direction. First, switching of the control mode for mover 5A will be described. As shown in Figure 5, sensor head 25 of coil set 17(1) does not face mover 5A, and the sensor head 25 is unable to read scale 23. Coil set 17(1) is in a mover standby state, and the discrimination unit 31 does not switch the control mode. In other words, the sensor head 25 does not detect or estimate the position of scale 23, and does not calculate the center position Pc of mover 5A.

[0043] A portion of coil set 17(2) faces mover 5A, and sensor head 25 changes from a state where it does not face mover 5A to a state where it faces mover 5A as mover 5A moves. In other words, reading of scale 23 by sensor head 25 changes from an impossible state to a possible state. Of the three coil sets 17(2), 17(3), and 17(4) at least a portion of which faces mover 5A, coil set 17(2) is the first coil set from the front in the direction of movement of mover 5A. Therefore, discrimination unit 31 switches coil set 17(2) to the sub-axis that performs torque assist control. Here, coil set 17(2) is referred to as the negative-side sub-axis because it is the sub-axis that assists the thrust of coil set 17(3), which is the main control axis adjacent to the negative side. Before the sensor head 25 faces the mover 5A, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17(2) from the detection position of the sensor head 25 of the coil set 17(3) adjacent to the negative side, and the calculation unit 29 calculates the center position Pc of the mover 5A based on the estimated detection position. After the sensor head 25 faces the mover 5A, the calculation unit 29 calculates the center position Pc of the mover 5A based on the detection position of the sensor head 25 of the coil set 17(2).

[0044] Whether or not the mover 5A faces at least a part of the coil set 17(2) is determined based on the calculated center position Pc of the mover 5A, and whether or not the leading end position of the mover 5A in the moving direction is on the coil set 17(2). The same applies to the other coil sets 17.

[0045] The entire coil set 17(3) faces the mover 5A, and the sensor head 25 faces the mover 5A, enabling reading of the scale 23. Of the three coil sets 17(2), 17(3), and 17(4), at least a portion of which faces the mover 5A, the coil set 17(3) is the second coil set from the front in the direction of movement of the mover 5A. Therefore, the discrimination unit 31 switches the coil set 17(3) to the main control axis that performs higher-level command control (position, speed, or torque control). The center position Pc of the mover 5A is calculated by the calculation unit 29 based on the position detected by the sensor head 25 of the coil set 17(3).

[0046] A portion of coil set 17(4) faces the mover 5A, and the sensor head 25 changes from facing the mover 5A to not facing the mover 5A as the mover 5A moves. In other words, the sensor head 25 changes from being able to read the scale 23 to being unable to do so. Of the three coil sets 17(2), 17(3), and 17(4) that at least partially face the mover 5A, coil set 17(4) is the third coil set from the front in the direction of movement of the mover 5A. Therefore, the discrimination unit 31 switches coil set 17(4) to the sub-axis that performs torque assist control. Here, coil set 17(4) is referred to as the positive-side sub-axis because it is the sub-axis that assists the thrust of coil set 17(3), the main control axis adjacent to the positive side. While the sensor head 25 faces the mover 5A, the calculation unit 29 calculates the center position Pc of the mover 5A based on the position detected by the sensor head 25 of coil set 17(4). After the sensor head 25 is no longer facing the movable element 5A, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17(4) from the detection position of the sensor head 25 of the coil set 17(3) adjacent to the positive side, and the calculation unit 29 calculates the center position Pc of the movable element 5A based on the estimated detection position.

[0047] The sensor head 25 of the coil set 17(5) does not face the mover 5A, and the sensor head 25 is unable to read the scale 23. The coil set 17(5) is in a mover standby state, and the control mode is not switched by the discrimination unit 31. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5A.

[0048] Next, switching of the control mode for the mover 5B will be described. Note that in the example shown in Fig. 5, the coil set 17(1) for the mover 5B is the same coil set as the coil set 17(5) for the mover 5A described above. As shown in Fig. 5, the sensor head 25 of the coil set 17(1) does not face the mover 5B, and the sensor head 25 is unable to read the scale 23. The coil set 17(1) is in a mover standby state, and the discrimination unit 31 does not switch the control mode. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5B.

[0049] A portion of coil set 17(2) faces the mover 5B, and the sensor head 25 changes from a state where it does not face the mover 5B to a state where it faces the mover 5B as the mover 5B moves. In other words, the sensor head 25 changes from an impossible state to a possible state for reading the scale 23. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2) that at least partially face the mover 5B, coil set 17(2) is the first coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches coil set 17(2) to the negative sub-axis for torque assist control. Before the sensor head 25 faces the mover 5B, the estimation unit 35 estimates the detection position of the sensor head 25 of coil set 17(2) from the detection position of the sensor head 25 of the coil set 17(3), which is adjacent to the mover 5B on the negative side. The calculation unit 29 calculates the center position Pc of the mover 5B based on the estimated detection position. After the sensor head 25 faces the mover 5B, the calculation unit 29 calculates the center position Pc of the mover 5B based on the detected position of the sensor head 25 of the coil set 17(2).

[0050] The entire coil set 17(3) faces the mover 5B, and the sensor head 25 faces the mover 5B so that it can read the scale 23. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2), at least a portion of which faces the mover 5B, the coil set 17(3) is the second coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(3) to the main control axis that performs higher-level command control (position, speed, or torque control). The center position Pc of the mover 5B is calculated by the calculation unit 29 based on the position detected by the sensor head 25 of the coil set 17(3).

[0051] The entire coil set 17(4-1) faces the mover 5B, and the sensor head 25 faces the mover 5B so that it can read the scale 23. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2), at least a portion of which faces the mover 5B, the coil set 17(4-1) is the third coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(4-1) to the positive sub-axis that performs torque assist control. The center position Pc of the mover 5B is calculated by the calculation unit 29 based on the detected position of the sensor head 25 of the coil set 17(4-1).

[0052] A portion of the coil set 17(4-2) faces the mover 5B, and the sensor head 25 changes from facing the mover 5A to not facing the mover 5A as the mover 5B moves. In other words, the sensor head 25 changes from being able to read the scale 23 to being unable to do so. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2) that at least partially face the mover 5B, the coil set 17(4-2) is the fourth coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(4-2) to the positive sub-axis that performs torque assist control. While the sensor head 25 faces the mover 5B, the calculation unit 29 calculates the center position Pc of the mover 5B based on the detected position of the sensor head 25 of the coil set 17(4-2). After the sensor head 25 is no longer facing the movable element 5B, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17 (4-2) from the detection position of the sensor head 25 of the coil set 17 (4-1) adjacent to the positive side, and the calculation unit 29 calculates the center position Pc of the movable element 5B based on the estimated detection position.

[0053] The sensor head 25 of the coil set 17(5) does not face the mover 5B, and the sensor head 25 is unable to read the scale 23. The coil set 17(5) is in a mover standby state, and the control mode is not switched by the discrimination unit 31. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5B.

[0054] Figure 6 shows the case where movers 5A and 5B move in the negative direction. First, switching of the control mode for mover 5B will be described. As shown in Figure 6, the sensor head 25 of coil set 17(1) does not face mover 5B, and the sensor head 25 is unable to read the scale 23. The coil set 17(1) is in a mover standby state, and the discrimination unit 31 does not switch the control mode. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and the center position Pc of the mover 5B is not calculated.

[0055] A portion of coil set 17(2) faces mover 5B, and sensor head 25 changes from a state where it does not face mover 5B to a state where it faces mover 5B as mover 5B moves. In other words, reading of scale 23 by sensor head 25 changes from an impossible state to a possible state. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2) at least a portion of which faces mover 5B, coil set 17(2) is the first coil set from the front in the direction of movement of mover 5B. Therefore, discrimination unit 31 switches coil set 17(2) to the sub-axis that performs torque assist control. Here, coil set 17(2) is referred to as the positive-side sub-axis because it is the sub-axis that assists the thrust of coil set 17(3), which is the main control axis adjacent to the positive side. Before the sensor head 25 faces the mover 5B, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17(2) from the detection position of the sensor head 25 of the coil set 17(3) adjacent to the positive side, and the calculation unit 29 calculates the center position Pc of the mover 5B based on the estimated detection position. After the sensor head 25 faces the mover 5B, the calculation unit 29 calculates the center position Pc of the mover 5B based on the detection position of the sensor head 25 of the coil set 17(2).

[0056] Whether or not the mover 5B faces at least a part of the coil set 17(2) is determined based on the calculated center position Pc of the mover 5B, and whether or not the leading end position of the mover 5B in the moving direction is on the coil set 17(2). The same applies to the other coil sets 17.

[0057] The entire coil set 17(3) faces the mover 5B, and the sensor head 25 faces the mover 5B so that it can read the scale 23. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2), at least a portion of which faces the mover 5B, the coil set 17(3) is the second coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(3) to the main control axis that performs higher-level command control (position, speed, or torque control). The center position Pc of the mover 5B is calculated by the calculation unit 29 based on the position detected by the sensor head 25 of the coil set 17(3).

[0058] The entire coil set 17(4-1) faces the mover 5B, and the sensor head 25 faces the mover 5B, enabling reading of the scale 23. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2), at least a portion of which faces the mover 5B, the coil set 17(4-1) is the third coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(4-1) to the sub-axis that performs torque assist control. Here, the coil set 17(4-1) is referred to as the negative-side sub-axis because it is the sub-axis that assists the thrust of the coil set 17(3), which is the main control axis adjacent to the negative side. The center position Pc of the mover 5B is calculated by the calculation unit 29 based on the detected position of the sensor head 25 of the coil set 17(4-1).

[0059] A portion of the coil set 17(4-2) faces the mover 5B, and the sensor head 25 changes from facing the mover 5B to not facing the mover 5B as the mover 5B moves. In other words, the sensor head 25 changes from being able to read the scale 23 to being unable to do so. Of the four coil sets 17(2), 17(3), 17(4-1), and 17(4-2) that at least partially face the mover 5B, the coil set 17(4-2) is the fourth coil set from the front in the direction of movement of the mover 5B. Therefore, the discrimination unit 31 switches the coil set 17(4-2) to the negative sub-axis that performs torque assist control. While the sensor head 25 faces the mover 5B, the calculation unit 29 calculates the center position Pc of the mover 5B based on the detected position of the sensor head 25 of the coil set 17(4-2). After the sensor head 25 is no longer facing the movable element 5B, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17 (4-2) from the detection position of the sensor head 25 of the coil set 17 (4-1) adjacent to the negative side, and the calculation unit 29 calculates the center position Pc of the movable element 5B based on the estimated detection position.

[0060] The sensor head 25 of the coil set 17(5) does not face the mover 5B, and the sensor head 25 is unable to read the scale 23. The coil set 17(5) is in a mover standby state, and the control mode is not switched by the discrimination unit 31. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5B.

[0061] Next, switching of the control mode for the mover 5A will be described. Note that in the example shown in Fig. 6, the coil set 17(1) for the mover 5A is the same coil set as the coil set 17(5) for the mover 5B described above. As shown in Fig. 6, the sensor head 25 of the coil set 17(1) does not face the mover 5A, and the sensor head 25 is unable to read the scale 23. The coil set 17(1) is in a mover standby state, and the discrimination unit 31 does not switch the control mode. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5A.

[0062] A portion of coil set 17(2) faces the mover 5A, and sensor head 25 changes from a state where it does not face the mover 5A to a state where it faces the mover 5A as the mover 5A moves. In other words, reading of the scale 23 by sensor head 25 changes from an impossible state to a possible state. Of the three coil sets 17(2), 17(3), and 17(4) at least a portion of which faces the mover 5A, coil set 17(2) is the first coil set from the front in the direction of movement of the mover 5A. Therefore, the discrimination unit 31 switches coil set 17(2) to the positive sub-axis for torque assist control. Before sensor head 25 faces the mover 5A, the estimation unit 35 estimates the detection position of sensor head 25 of coil set 17(2) from the detection position of sensor head 25 of coil set 17(3), which is adjacent to the mover 5A on the positive side. The calculation unit 29 calculates the center position Pc of the mover 5A based on the estimated detection position. After the sensor head 25 faces the mover 5A, the calculation unit 29 calculates the center position Pc of the mover 5A based on the position detected by the sensor head 25 of the coil set 17(2).

[0063] The entire coil set 17(3) faces the mover 5A, and the sensor head 25 faces the mover 5A, enabling reading of the scale 23. Of the three coil sets 17(2), 17(3), and 17(4), at least a portion of which faces the mover 5A, the coil set 17(3) is the second coil set from the front in the direction of movement of the mover 5A. Therefore, the discrimination unit 31 switches the coil set 17(3) to the main control axis that performs higher-level command control (position, speed, or torque control). The center position Pc of the mover 5A is calculated by the calculation unit 29 based on the position detected by the sensor head 25 of the coil set 17(3).

[0064] A portion of coil set 17(4) faces the mover 5A, and sensor head 25 changes from a state in which it faces mover 5A to a state in which it does not face mover 5A as the mover 5A moves. In other words, reading of scale 23 by sensor head 25 changes from a possible state to a non-possible state. Of the three coil sets 17(2), 17(3), and 17(4) that at least partially face mover 5A, coil set 17(4) is the third coil set from the front in the direction of movement of mover 5A. Therefore, discriminator 31 switches coil set 17(4) to the negative sub-axis that performs torque assist control. While sensor head 25 faces mover 5A, calculator 29 calculates the center position Pc of mover 5A based on the detected position of sensor head 25 of coil set 17(4). After the sensor head 25 is no longer facing the mover 5A, the estimation unit 35 estimates the detection position of the sensor head 25 of the coil set 17(4) from the detection position of the sensor head 25 of the coil set 17(3) adjacent to the negative side, and the calculation unit 29 calculates the center position Pc of the mover 5A based on the estimated detection position.

[0065] The sensor head 25 of the coil set 17(5) does not face the mover 5A, and the sensor head 25 is unable to read the scale 23. The coil set 17(5) is in a mover standby state, and the control mode is not switched by the discrimination unit 31. In other words, the sensor head 25 does not detect or estimate the position of the scale 23, and does not calculate the center position Pc of the mover 5A.

[0066] In the above description, the mover 5A has a length equivalent to two coil sets 17, and the mover 5B has a length equivalent to three coil sets 17. However, the length of the mover 5 may be four or more coil sets 17. The length of the mover 5 is not limited to an integer multiple of the coil set 17, and may be a real multiple of the coil set 17, such as 1.5 times or 2.7 times. The length of the mover 5 may be less than the length of one coil set 17, such as 1 time or 0.8 times.

[0067] <5. Effects of the embodiment> As described above, in the linear conveyance system 1 of this embodiment, the multi-axis amplifier 11 controls the movement of the mover 5 by dividing the multiple coil sets 17 into a main control axis coil set that supplies power by position, speed, or torque control based on a position, speed, or torque command, and a sub-axis coil set that supplies power by torque control based on a torque command output by position, speed, or torque control on the main control axis. This allows the coil sets 17 of the stator 3 to be controlled separately as a main coil set that primarily controls the movement of the mover 5 and a sub-coil set that auxiliary controls the movement of the mover 5. This makes it easy to achieve cooperative control of the same mover 5 by multiple coil sets 17. Furthermore, torque assist control can be achieved in which the main control axis coil set 17 applies a thrust to move the mover 5 to a target position, target speed, or target torque, while the sub-axis coil set 17 assists the thrust.

[0068] Furthermore, in this embodiment, the length of the mover 5 in the movement direction is longer than that of the coil sets 17 of the stator 3, and the multi-axis amplifier 11 may control the movement of the mover 5 by sequentially switching the coil sets 17, at least a portion of which faces the mover 5, to either the coil set of the main control axis or the coil set of the sub-axis. In this case, the coil sets 17 facing the mover 5 can be sequentially switched to the main control axis or the sub-axis as the mover 5 moves. In this way, cooperative control by multiple coil sets 17 facing the mover 5 can be realized.

[0069] Furthermore, in this embodiment, the multi-axis amplifier 11 may have a calculation unit 29 that calculates the reference position of the mover 5 based on the detection data of the sensor head 25, and a determination unit 31 that determines whether the coil set 17 facing the mover 5 should be switched to the main control axis or the sub-axis based on the reference position. In this case, regardless of where the mover 5 is located on the stator 3, the coil set 17 facing the mover 5 can be switched to appropriate control based on the positional relationship between the reference position of the mover 5 and the coil set 17.

[0070] Furthermore, in this embodiment, the calculation unit 29 may calculate the center position Pc in the movement direction of the mover 5 based on the detection data Fb of the sensor head 25, the machine coordinate offset amount obtained by accumulating the arrangement intervals of the sensor heads 25 from the origin, and the length Lm of the mover 5 in the movement direction. In this case, the following effect is obtained. That is, if the reference position of the mover 5 calculated by the calculation unit 29 is not the center position, it is necessary to switch the reference position depending on the movement direction of the mover 5. According to this embodiment, the calculation unit 29 calculates the center position of the mover 5 as the reference position, and therefore, whether the movement direction of the mover 5 is the positive direction or the negative direction, it is possible to switch to appropriate control using the common center position Pc.

[0071] Furthermore, in this embodiment, the discriminator 31 may switch the coil set 17 second from the front in the moving direction of the mover 5, of the coil sets at least a portion of which faces the mover 5, to the main control axis, and switch the coil sets 17 other than the second one to the sub-axes. In this case, the following effect is obtained. That is, when the length of the mover 5 in the moving direction is equal to or longer than the length of two coil sets 17, the entire coil set 17 second from the front in the moving direction of the mover 5 faces the mover 5. Therefore, by setting the second coil set 17 as the main control axis and the other coil sets 17 as the sub-axes, it is possible to stabilize cooperative control and improve the thrust of the mover 5.

[0072] Furthermore, in this embodiment, each multi-axis amplifier 11 may have a sharing unit 33 that shares at least one of the detection data of the sensor head 25 corresponding to the main control axis and the detection data of the sensor head 25 corresponding to the sub-axis among the multiple multi-axis amplifiers 11. In this case, the following effect is obtained. That is, depending on the position of the mover 5, even if a part of the coil set 17 faces the mover 5, the sensor head 25 of that coil set 17 may not be able to detect the scale 23. According to this embodiment, even when the coil set 17 is in such an unstable state, by sharing the detection data of the sensor heads 25 for the main control axis or the sub-axis, the detection data can be estimated using the shared detection data. As a result, even when the coil set 17 is in an unstable state, the center position Pc of the mover 5 can be estimated and appropriate control can be switched to.

[0073] Furthermore, in this embodiment, the multi-axis amplifier 11 may include an estimation unit 35 that estimates the detection data of the sensor head 25 of the coil set 17 based on the detection data of the sensor head 25 of the coil set 17 that is adjacent to at least one of the positive side and the negative side in the movement direction of the mover 5, which is shared by the sharing unit 33. In this case, even if there is a coil set 17 in an unstable state in which the sensor head 25 is not detecting the scale 23 among the coil sets 17 at least a portion of which faces the mover 5, the detection data can be estimated using the detection data of the sensor head 25 of the coil set 17 that is adjacent to at least one of the positive side and the negative side in the movement direction of the mover 5. As a result, even for a coil set 17 that is in an unstable state, it is possible to estimate the center position Pc of the mover 5 and switch to appropriate control.

[0074] <6. Variations> The disclosed embodiments are not limited to those described above, and various modifications are possible within the scope of the spirit and technical concept of the present invention. Such modifications will be described below.

[0075] (6-1. When providing an identification magnet on the mover) In a linear conveyance system 1 having a plurality of movers 5, it is necessary to identify each of the movers 5. In the above embodiment, the scale 23 of the mover 5 includes a mover identification means, but the method for identifying the movers 5 is not limited to the above. For example, each mover 5 may be provided with an identification magnet.

[0076] FIG. 7 shows an example of the sensor configuration of the stator 3 and the magnet configuration of the movers 5A and 5B in this modified example. Note that FIG. 7 shows the stator 3 and the movers 5A and 5B separated from each other. As shown in FIG. 7, the stator 3 has a plurality of pairs of magnetic sensors 45A and 45B as sensor heads 25. The magnetic sensors 45A and 45B are, for example, Hall elements, and are arranged for each coil set 17. The magnetic sensors 45A and 45B detect the magnets 21 of the movers 5A and 5B and output two-phase detection signals that are 90° out of phase with each other in electrical angle. The magnets 21 have north and south poles alternately arranged in the direction of movement, and the detection signals output by the magnetic sensors 45A and 45B are incremental signals. The magnets 21, together with the coil set 17 consisting of three-phase coils, form a linear motor and also form a scale 23 detected by the magnetic sensors 45A and 45B.

[0077] The stator 3 also has a plurality of magnetic sensors 47 arranged at predetermined intervals. The magnetic sensors 47 are, for example, latch-type Hall ICs that detect magnets 49 provided on the movers 5A and 5B and output detection signals. In the example shown in FIG. 7 , the length of each of the movers 5A and 5B in the movement direction is, for example, the length L of two coil sets 17, and the magnetic sensors 47 are also arranged at intervals corresponding to two coil sets 17. Note that the arrangement intervals of the magnetic sensors 47 may be other than those described above. Each of the movers 5A and 5B is provided with a magnet 49S at both ends in the movement direction. Each of the movers 5A and 5B is also provided with a magnet 49N between the magnets 49S. Each of the magnets 49S and 49N is composed of a magnet with a south pole and a north pole. The interval between the magnet 49S and the magnet 49N is set individually for each mover 5, and this interval functions as a mover identification means. 7, the distance between magnet 49S and magnet 49N (for example, when the output of magnetic sensor 47 is High) is L1 for mover 5A and L2 for mover 5B. In this modification, the distances moved in the positive and negative directions by movers 5A and 5B while magnet 49S and magnet 49N are detected by magnetic sensor 47 are measured using detection signals from magnetic sensors 45A and 45B, thereby detecting the distances L1 and L2 and identifying each of movers 5A and 5B.

[0078] Identification of each mover 5A, 5B is performed, for example, by moving each mover 5A, 5B a predetermined distance in the positive or negative direction before starting operation of the linear conveyance system 1, and the identification result is shared between each multi-axis amplifier 11. Therefore, identification of each mover 5 needs to be performed only once. Note that identification of each mover 5 may also be performed constantly while the linear conveyance system 1 is in operation.

[0079] (6-2. When switching control gains) The multi-axis amplifier 11 may execute the above-mentioned upper command control (position, speed, or torque control) and torque assist control by appropriately switching the control gain.

[0080] 1, in the area between the carry-out device R3 and the carry-in device R2, the load weight of the mover 5 is, for example, 0 because no workpiece W is placed thereon, and in the area between the carry-in device R2 and the first processing device R1, the load weight of the mover 5 is, for example, the weight of the carried-in workpiece W, and in the area of ​​each processing device R1, the load weight of the mover 5 is, for example, a weight according to the processing content of the workpiece W. In this way, since the load weight of the mover 5 in each area is known in advance, the control gain may be set for each area of ​​the linear conveyance system 1, and each multi-axis amplifier 11 may be controlled by switching to a control gain according to the area in which the coil set 17 to be controlled is located.

[0081] Furthermore, for example, if the lengths or masses of the movers 5 are different, the lengths and masses are grasped by the mover identification means. For this reason, the control gains may be set for each mover identification means, and each multi-axis amplifier 11 may identify the mover identification means of the mover 5 to be controlled, and switch to a control gain that corresponds to the mover identification means.

[0082] It is possible to perform both the switching for each area and the switching for each mover identifying means. Also, the control gain may be switched by referring to a table, for example.

[0083] (6-3. Generating virtual position or speed commands in torque control) When the coil set 17 is switched from the main control axis to the sub-axis, a torque command is generated in the higher-level command control (either position or speed control) of the main control axis, so shock is suppressed when switching to torque control of the sub-axis. On the other hand, when the coil set 17 is switched from the sub-axis to the main control axis, a position command or speed command is not generated in the torque control of the sub-axis, so shock may occur when switching to higher-level command control (either position or speed control) of the main control axis. Therefore, in torque control of the sub-axis, calculations may be performed assuming that position control or speed control is performed virtually, and a virtual position command or speed command may be generated. This makes it possible to suppress shock when switching the coil set 17 from the sub-axis to the main control axis.

[0084] <7. Example of hardware configuration for multi-axis amplifier> An example of the hardware configuration of the multi-axis amplifier 11 will be described with reference to Fig. 8. In Fig. 8, the configuration related to the function of supplying power to the coil set 17 of the multi-axis amplifier 11 is omitted from the illustration.

[0085] 8, the multi-axis amplifier 11 includes, for example, a CPU 901, a ROM 903, a RAM 905, a dedicated integrated circuit 907 configured for a specific application such as an ASIC or FPGA, an input device 913, an output device 915, a recording device 917, a drive 919, a connection port 921, and a communication device 923. These components are connected via a bus 909 and an input / output interface 911 so as to be able to transmit signals to each other.

[0086] The program can be recorded in, for example, the ROM 903, the RAM 905, or a recording device 917 such as a hard disk.

[0087] The program may also be temporarily or non-temporarily (permanently) recorded on a removable recording medium 925, such as a magnetic disk such as a flexible disk, various optical disks such as CDs, MO disks, and DVDs, or a semiconductor memory. Such recording medium 925 may also be provided as a so-called package software. In this case, the program recorded on the recording medium 925 may be read by the drive 919 and recorded on the recording device 917 via the input / output interface 911, the bus 909, etc.

[0088] The program may also be recorded, for example, on a download site, another computer, or another recording device (not shown). In this case, the program is transferred via a network NW such as a LAN or the Internet, and the communication device 923 receives the program. The program received by the communication device 923 may then be recorded in the recording device 917 via the input / output interface 911, the bus 909, or the like.

[0089] The program may also be recorded in, for example, an appropriate externally connected device 927. In this case, the program may be transferred via an appropriate connection port 921 and recorded in the recording device 917 via the input / output interface 911, the bus 909, etc.

[0090] Then, the CPU 901 executes various processes in accordance with the programs recorded in the recording device 917, thereby realizing processes by the recording unit 27, calculation unit 29, discrimination unit 31, sharing unit 33, estimation unit 35, motor control unit 37, etc. In this case, the CPU 901 may, for example, read the program directly from the recording device 917 and execute it, or may execute it after loading it once into the RAM 905. Furthermore, when the CPU 901 receives a program via the communication device 923, drive 919, or connection port 921, for example, it may execute the received program directly without recording it in the recording device 917.

[0091] Furthermore, the CPU 901 may perform various processes as necessary based on signals and information input from an input device 913 such as a mouse, keyboard, and microphone (not shown).

[0092] The CPU 901 may then output the results of the above processing from an output device 915, such as a display device or an audio output device, and further, if necessary, the CPU 901 may transmit the processing results via a communication device 923 or a connection port 921, or may record the results in the recording device 917 or recording medium 925.

[0093] In the above description, when terms such as "vertical," "parallel," and "plane" are used, they are not used in their strict sense. In other words, "vertical," "parallel," and "plane" mean "substantially vertical," "substantially parallel," and "substantially plane," allowing for tolerances and errors in design and manufacturing.

[0094] Furthermore, in the above description, when the external dimensions, size, shape, position, etc. are described as "same," "equal," "different," etc., these descriptions do not have the strict meaning. In other words, "same," "equal," and "different" mean "substantially the same," "substantially the same," "substantially equal," and "substantially different," allowing for design and manufacturing tolerances and errors.

[0095] Furthermore, in addition to what has already been described above, the methods according to the above-described embodiments and modifications may be used in appropriate combinations. Although not specifically illustrated, the above-described embodiments and modifications may be implemented with various modifications within the scope of their spirit.

[0096] Furthermore, the problems and effects that the above-described embodiments and modifications are intended to solve are not limited to those described above. That is, the embodiments and modifications may solve problems or achieve effects that are not described above, or may solve only some of the problems or achieve only some of the effects that are described. [Explanation of symbols]

[0097] 1. Linear transport system 3 Stator 5 Mover 11 Multi-axis amplifier (example of control device) 13 Linear Controller 17 coil sets 21 Magnet 23 scale 25 Sensor head (example of a sensor) 27 Recording Section 29 Calculation Unit 31 Discrimination part 33 Common area 35 Estimation part 37 Motor control unit 39 Position control section 41 Speed ​​control section 43 Current control section

Claims

1. a stator having a plurality of coil sets each consisting of a three-phase coil; a mover having a magnet and moving along the stator; a control device that controls movement of the mover by dividing the plurality of coil sets into a first coil set that is powered by a first control based on a first command and a second coil set that is powered by a second control based on a second command output by the first control; A linear transport system equipped with

2. The mover is The length in the moving direction is longer than that of the coil set, The control device The coil set, at least a portion of which faces the mover, is sequentially switched to either the first coil set or the second coil set to control the movement of the mover. The linear transport system according to claim 1 .

3. The linear transport system includes: a scale provided on the mover; a plurality of sensors disposed for each of the coil sets and detecting the scale; Furthermore, The control device a calculation unit that calculates a reference position of the mover based on the detection data of the sensor; a determination unit that determines whether the coil set facing the mover is switched to either the first coil set or the second coil set based on the reference position; The linear transport system according to claim 2 , further comprising:

4. The calculation unit calculating a center position of the mover in the movement direction based on the detection data of the sensors, an accumulated value obtained by accumulating the arrangement intervals of the sensors from the origin, and the length of the mover in the movement direction; The linear transport system according to claim 3 .

5. The determination unit Among the coil sets at least a portion of which faces the mover, the second coil set from the front in the moving direction of the mover is switched to the first coil set, and the coil sets other than the second coil set are switched to the second coil set. The linear transport system according to claim 3 .

6. The control device Power is supplied to the first coil set by position, speed, or torque control based on a position, speed, or torque command, and power is supplied to the second coil set by torque control based on a torque command output by the position, speed, or torque control. The linear transport system according to any one of claims 1 to 5.

7. The linear transport system includes: a scale provided on the mover; a plurality of sensors disposed for each of the coil sets and detecting the scale; Furthermore, The control device A plurality of coils are arranged for each of one or a predetermined number of the coil sets, Each control device is a sharing unit that shares at least one of the detection data of the sensor corresponding to the first coil set and the detection data of the sensor corresponding to the second coil set among the plurality of control devices; The linear transport system according to claim 1 .

8. The control device an estimation unit configured to estimate, when there is a coil set in which the sensor does not detect the scale among the coil sets at least a portion of which faces the mover, the detection data of the sensor of the coil set in question based on the detection data of the sensor of the coil set adjacent to the mover on at least one of the positive side and the negative side in the moving direction, which is shared by the sharing unit; The linear transport system according to claim 7 .

9. a stator having a plurality of coil sets each consisting of a three-phase coil; a mover having a magnet and moving along the stator; A control method for a linear transport system having controlling the movement of the mover by dividing the plurality of coil sets into a first coil set to which power is supplied by a first control based on a first command and a second coil set to which power is supplied by a second control based on a second command output by the first control; A control method for a linear transport system having the above structure.

10. a stator having a plurality of coil sets each consisting of a three-phase coil; a mover having a magnet and moving along the stator; A control device for a linear transport system having The coil set is sequentially switched to one of position, speed, and torque control, or torque control based on a torque command output by one of the position, speed, and torque control, thereby controlling the movement of the mover. Control device for linear transport system.

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