JP3521251B2 - Linear motor control method and device, and turntable device for transporting articles - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a plurality of linear motors and an apparatus used for implementing the method.

[0002]

2. Description of the Related Art In some cases, a linear motor having a plurality of armatures operates one object, for example, an article transport turntable in a factory.

In controlling a linear motor having a plurality of armatures as described above, all the armatures are usually controlled by one servo driver, or the armatures are divided into a plurality of groups, and one servo is provided for each group. The driver is assigned and controlled by this. 9 and 10 are block diagrams showing a configuration of a main part of a conventional linear motor control device. In FIG. 9, the servo driver D controls all the armatures M, M, ...
Connected to these. The servo driver D receives a start signal from the host controller 1 and receives the armatures M, M,
The armatures M, M, M ... Are activated by activating M ... and receiving a signal indicating the position on the moving side of the linear motor from the rotary encoder 2 mounted on the runner side of the linear motor to perform feedback control. When it is driven and receives a stop signal from the host controller 1, the armatures M, M,
It is designed to stop M ...

Further, in FIG. 10, all armatures M,
The M, M, ... Are divided into a plurality of groups G1, G2, G3 ,.
Servo drivers D1, D2, D3, ... Are connected to the respective groups G1, G2, G3, ..., and the armatures M, M included in one group are controlled by one connected servo driver. It is supposed to be done. Each of the servo drivers D1, D2, D3, ... Is connected to one upper controller 1 and receives a start signal from the upper controller 1 to receive groups G1, G2.
The armatures M, M in G3, ... Are activated. Armature M, M,
The rotary encoder 2 mounted on the runner side of M, ... Is also mounted to output signals to the respective servo drivers D1, D2, D3 ,. ... independently perform feedback control to drive the armatures M, M, M, .... When the respective servo drivers D1, D2, D3, ... Receive a stop signal from the host controller 1, the respective servo drivers D1, D2, D3, ... Stop the armatures M, M in the connected group. Let

FIG. 11 is a block diagram showing a structure of a main part of a conventional servo driver. As a power supply for driving the armature M, a three-phase AC power supply S is provided outside the servo driver D. The servo driver D includes a rectifier R and an inverter circuit I, rectifies the three-phase AC current generated by the three-phase AC power source S by the rectifier R, and the DC current obtained by the rectifier R is required by the inverter circuit I. The three-phase alternating current is converted into a three-phase alternating current having a frequency and an amplitude corresponding to various running speeds and generated thrusts, and the obtained three-phase alternating current is supplied to the armature M.

Further, the servo driver D controls the speed of the armature M by adjusting the frequency and amplitude of the three-phase alternating current obtained by the inverter circuit I, and the CPU 3, ROM 4, D / A converter 5,
A PWM pattern calculator 6 and a gate pulse generator 7 are provided. The CPU 3 receives the output signals of the host controller 1 and the rotary encoder 2, and receives the ROM.
The frequency and the amplitude of the three-phase alternating current to be given to the armature M are calculated by performing the processing in accordance with the program stored in 4. The D / A converter 5 converts a digital signal output from the CPU into an analog signal, and the PWM pattern calculator 6 determines a PWM pattern of a three-phase AC voltage to be applied to the armature M from the analog signal. . Then, by applying the gate signal generated by the gate pulse generator 7 to the gate of the power switching element of the inverter circuit I based on the output signal of the PWM pattern calculator 6, a three-phase AC having a required frequency and amplitude is obtained. An electric current is supplied to the armature M.

[0007]

By the way, in the conventional linear motor control device as described above, when controlling all the linear motors by one servo driver, a three-phase alternating current must be supplied to many armatures. Inevitably, the inverter circuit needs to have a large electric capacity, resulting in a very high cost.

Further, there is a problem in that it is necessary to mount a servo driver having an electric capacity suitable for the load for each device, and it is not possible to share parts.

In order to solve such a problem, by controlling a plurality of armatures divided into a plurality of groups for each group by a plurality of servo drivers, each servo driver has a common electric capacity. It was usually small. However, in this case, since the control is performed individually by each servo driver, there is a problem in that the generated thrust of the armature varies due to the difference in responsiveness of each servo driver, resulting in malfunction.

Further, when the mechanical frequency of the linear motor, that is, the natural frequency and the frequency of the control signal output from the control device are close to or the same as each other, resonance occurs, which causes the speed and the positioning. There was a problem that the accuracy deteriorated. FIG. 8A is a graph showing the vibration component of the machine base of the article transfer turntable device using the conventional linear motor control device. The natural frequency of the machine base of this article transport turntable device is 22 Hz, and vibration occurs at the natural frequency and a frequency that is an integral multiple thereof.

Therefore, in order to suppress the occurrence of vibration, a linear motor control device as disclosed in Japanese Patent Laid-Open No. 9-121589 is used. This is a band attenuation filter whose attenuation band is near the natural frequency.
/ A converter installed after the A / A converter to suppress the occurrence of resonance of the linear motor by attenuating the frequency component in the band near the natural frequency from the analog signal output from the D / A converter. Is.

However, in such a conventional linear motor control device, it is necessary to install a band attenuation filter inside the servo driver, and a dedicated servo driver must be provided for each natural frequency, that is, for each linear motor. Not
The cost was very high.

The present invention has been made in view of the above circumstances, and divides a plurality of armatures of a linear motor into a plurality of groups, controls the armatures of one group by a first servo driver, and The armatures in each group are controlled by the second servo driver that operates by an electric signal output from the first servo driver, and the thrust generated by the armatures included in the other group is controlled by the second servo driver. An object of the present invention is to provide a method of controlling a linear motor and a device therefor, which can drive a plurality of armatures favorably, and a turntable device for article transport, which are low in cost as compared with the related art by making the thrust almost the same as the generated thrust. And

Another object of the present invention is to extract the same frequency component as the natural frequency of the linear motor from the electric signal output from the first servo driver to the second servo driver and invert it to the opposite phase, By operating the second servo driver in addition to the electric signal, the resonance from the armature controlled by the second servo driver can be canceled and the second servo driver can be operated at a lower cost than the conventional one. (1) It is an object of the present invention to provide a linear motor control method and apparatus for canceling resonance caused by an armature controlled by one servo driver, and a turntable device for article transportation.

[0015]

A linear motor control method according to a first aspect of the present invention is a linear motor control method for controlling a linear motor having a plurality of armatures for operating one object. Position and running of the child
The linear model output from the encoder that detects the magnetic pole of the child
The traveling speed and / or the generated thrust of the linear motor are determined by one first servo driver which performs feedback control based on the position signal of the motor, and the frequency corresponding to the determined traveling speed and / or the determined generated thrust is determined. The first AC current having a corresponding amplitude is supplied to a part of the armature, and the analog according to the traveling speed and / or the generated thrust.
The grayed signal output to one or more second servo driver,
By the second servo driver, a frequency corresponding to the traveling speed and / or an amplitude corresponding to the generated thrust and
Calculated according to the magnetic pole of the runner detected by the encoder
A second alternating current having a phase is supplied to another armature.

A linear motor control method according to a second aspect of the present invention is the linear motor control method according to the first aspect of the present invention.
The alternating current supplied to the other armature by the second servo driver in order to remove the vibration of a predetermined frequency from the generated thrust of the part of the armature supplied with the alternating current by the first servo driver. It is characterized by determining the frequency and / or the amplitude.

The control system for a linear motor according to the third invention includes a plurality of armatures, in the control system for a linear motor for controlling the linear motor for operating the one object, the position and the traveling way of the linear motor An encoder for detecting the magnetic pole of the runner, a first converter for converting the frequency and / or the amplitude of the alternating current, and a first calculation for calculating the deviation between the position of the linear motor detected by the encoder and a target position given in advance. A second arithmetic unit for calculating the frequency and / or the amplitude of the alternating current to be supplied to the armature of the linear motor according to the result calculated by the first arithmetic unit;
A first driver that drives the first converter according to the result calculated by the arithmetic unit, and a result calculated by the second arithmetic unit.
A first output terminal for outputting a corresponding analog signal;
Servo driver and alternating current frequency and / or amplitude
Second converter for converting the travel, traveling detected by the encoder
AC power to be output from the second converter according to the magnetic pole of the child
Means for calculating the phase of the flow, inputting the analog signal
Based on the input terminal and the phase and analog signals
And a second servo driver having a second driver for driving the second converter .

A linear motor control device according to a fourth aspect of the present invention is the linear motor control device according to the third aspect of the present invention.
The alternating current whose frequency and / or amplitude is converted by the second servo driver is converted into alternating current that drives the other armature so as to cancel the vibration of a predetermined frequency from the thrust generated by the part of the armature. Therefore, a signal conversion unit for converting the analog signal output from the first servo driver to the second servo driver is provided between the first servo driver and the second servo driver. .

A linear motor control device according to a fifth aspect of the present invention is the linear motor control device according to the fourth aspect of the present invention.
The signal conversion unit includes a bandpass filter for a pass band including the predetermined frequency, and inverts a phase of a signal output by the bandpass filter to synthesize the output signal of the first servo driver. And

An article-conveying turntable device according to a sixth aspect of the invention is an article-conveying turntable device comprising a linear motor having a plurality of armatures, the table body being rotated by the linear motor. A linear motor control device according to any one of the third to fifth inventions is provided.

In the linear motor control method according to the first invention and the linear motor control device according to the third invention, a part of the armature is controlled by one first servo driver, and the first servo driver An electric signal corresponding to the calculated traveling speed and / or generated thrust of the linear motor is output to the second servo driver, and the second servo driver controls another armature based on the electric signal (analog signal). Therefore, the control amount by which the second servo driver controls the armature is substantially the same as the control amount by the first servo driver,
Therefore, the generated thrust of each armature has less variation than in the conventional case, and it is possible to favorably drive the linear motor having a plurality of armatures.

In the case of the linear motor control method according to the second aspect of the invention and the linear motor control device according to the fourth aspect of the invention, mechanical vibrations due to thrust force fluctuations of some armatures and thrusts of other armatures are detected. Since it is suppressed by controlling, it is possible to favorably prevent the occurrence of the mechanical vibration.

In the case of the linear motor control device according to the fifth aspect of the invention, the frequency component in the band near the natural frequency of the linear motor is extracted from the electrical signal sent from the first servo driver to the second servo driver, and the phase is extracted. Invert
The obtained electric signal is combined with the original electric signal, and the armature of the linear motor is controlled using this, so that the vibration generated by the thrust generated by a part of the armature controlled by the first servo driver is generated. , And can be suppressed by the thrust generated by another armature controlled by the second servo driver.

In the case of the article conveying turntable device according to the sixth invention, the linear motor control device according to any one of the third to fifth inventions is provided, so that the cost is lower than the conventional one. The speed and position of the turntable can be controlled with high accuracy.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 Hereinafter, the present invention will be described in detail with reference to the drawings showing an embodiment thereof. FIG. 1 is a partial side sectional view showing a configuration of a main part of a first embodiment of an article transporting turntable device according to the present invention.

In the figure, 20 is a table body having a donut-shaped planar shape. Around the outer periphery of the table body 20, a plurality of carrier heads 10 having a function of gripping an object X to be processed such as assembling, painting and the like and vertically swinging are provided.
A leg F of the transfer machine is erected in a space at the center of 0.

The carrier head 10 is supported on the outer circumference of the table body 20 by a carrier head supporting bracket 21, and a machine base 40 installed below the table body 20 and the carrier head supporting bracket 2 are supported.
A carrier head swivel cam mechanism 70 including a cam roller 71 and a cam rail 72 is installed between the inner lower end of the carrier head 1 and the inner lower end portion of the No. 1 so as to swivel the carrier head 10 in the vertical direction.

A linear motor 30 for rotating the table is installed between the table body 20 and the machine base 40. The linear motor 30 includes a plurality of secondary-side magnet plates (runners) 31 fixed to the bottom surface of the table body 20 over the entire circumference, and a peripheral surface of the machine base 40 in a state of facing the secondary-side magnet plates. It is composed of a plurality of primary side coils (armatures) 32 provided at substantially equal intervals in the direction.
Between the table body 20 and the machine base 40, the table body 20 and a large number of carrier heads 1 provided on the outer periphery thereof.
In order to support the total load of 0 and to rotate the table body 20 smoothly, both inside and outside of the linear motor 30,
Eight rollers are equally arranged in the circumferential direction.

Further, the table body 20 has a virtual central axis Z-.
A table rotation center setting mechanism 50 in which four guide rollers abut on the inner peripheral surface of the table body 20 at equal intervals in the circumferential direction in order to rotate accurately horizontally about Z It is installed on the circumference side. And
On the upper surface of the inner edge portion facing the central space of the table body 20, four floating prevention rollers 80 are equally arranged in the circumferential direction to press the table body 20 downward.

FIG. 2 is a plan view showing the structure of the essential parts of the embodiment 1 of the article conveying turntable device according to the present invention. The article-conveying turntable device configured as described above is installed at a position adjacent to the carrying-in means (not shown) for carrying in the object to be processed X and the carrying-out means (not shown) for carrying out the object to be processed X. Has been done. The object X to be processed is received and received by the carrier head 10 from the carry-in means,
Is rotated by a predetermined angle by driving the linear motor 30,
The processing object X is transferred. The linear motor 30 electromagnetically generates a rotational driving force by supplying a three-phase alternating current to the primary side coil (armature). In this way, while repeating the rotation and stop of the table body 20,
A plurality of processing devices installed around the article transport turntable device assembles the object X to be processed, performs processing such as painting, and hands the processed object X to the unloading means.

FIG. 3 is a block diagram showing the configuration of the main part of the first embodiment of the linear motor control device according to the present invention. In the figure, M is an armature (stator) of the linear motor
Is. In this linear motor, one traveling element including a plurality of magnets is provided with a plurality of armatures M,
All the armatures M, M, M, ... Are divided into a plurality of groups G1, G2, G3 ,. The first servo driver DM is connected to the group G1, and the other groups G2, G3, G
Connected to the second servo drivers DS2, DS3, DS4, ... Connected to the first servo driver DM. The first servo driver DM is connected to one upper controller 1, and receives the activation signal from the upper controller 1 to activate the armatures M, M in the group G1. The rotary encoder 2 mounted on the runner side of the armature M, M, M, ... Is also mounted to output a signal to the first servo driver DM,
Upon receiving this signal, the first servo driver DM performs feedback control to determine the traveling speed and the generated thrust of the linear motor, and to drive the linear motor with the determined traveling speed and the generated thrust, the armature M in the group G1. , M are driven. Then, when the first servo driver DM receives the stop signal from the host controller 1, the first servo driver DM operates to stop the armatures M, M in the group G1.

Further, each second servo driver DS2
DS3, DS4, ... Input electric signals corresponding to the traveling speed and the generated thrust determined by the first servo driver DM. Further, it is also connected to the rotary encoder 2 so that a signal output from the rotary encoder 2 is input. In the second servo drivers DS2, DS3, DS4, ..., The magnetic pole of the magnet of the runner is detected by the output signal of the rotary encoder, and the detected magnetic pole and the first servo driver DM
The speed control of the armatures M, M, M, ... Within the groups G2, G3, G4 ,.

FIG. 4 is a block diagram showing the structure of the main part of the first servo driver DM. A three-phase AC power source S is provided outside the first servo driver DM as a power source for driving the armature M.
Is provided. The first servo driver DM includes a rectifier R and an inverter circuit I, and rectifies the three-phase AC current generated by the three-phase AC power supply by the rectifier R,
The direct current obtained by this is applied to the inverter circuit I.
Is converted into a three-phase alternating current having a frequency and amplitude corresponding to the required traveling speed and generated thrust, and the obtained three-phase alternating current is supplied to the armature M.

The first servo driver DM controls the speed of the armature M by adjusting the frequency and amplitude of the three-phase alternating current obtained by the inverter circuit I. The CPU 3, ROM 4, It is provided with a D / A converter 5, an output terminal P _OUT , a PWM pattern calculator 6, and a gate pulse generator 7. The CPU 3 is
By receiving the output signals of the host controller 1 and the rotary encoder 2 and performing processing according to the program stored in the ROM 4, the frequency and amplitude of the three-phase alternating current to be given to the armature M are calculated. The CPU3
A digital signal output by the D / A converter 5 is converted into an analog signal, and a PWM pattern of a three-phase AC voltage to be applied to the armature M from the analog signal is converted into the PWM pattern.
It is determined by the pattern calculator 6. Then, the gate signal generated by the gate pulse generator 7 based on the output signal of the PWM pattern calculator 6 is converted into the inverter circuit I.
By supplying to the gate of the power switching element, the three-phase alternating current having the required frequency and amplitude is supplied to the armature M. The analog signal output from the D / A converter 5 is output to the outside through an output terminal P _OUT .

On the other hand, the second servo drivers DS2 and DS
3, DS4, ... Have the following configurations. FIG. 5 shows the second servo drivers DS2, DS3, DS4, ...
3 is a block diagram showing the configuration of the main part of FIG. The three-phase AC power supply S is used as a power supply for driving the armature M. The second servo drivers DS2, DS3, DS4, ...
Like the servo driver DM, the rectifier R and the inverter circuit I are provided, and the three-phase AC current generated by the three-phase AC power source is rectified by the rectifier R, and the DC current obtained by the rectifier R is rectified by the inverter circuit I. The three-phase alternating current is converted into a three-phase alternating current having a frequency and amplitude corresponding to the required traveling speed and generated thrust, and the obtained three-phase alternating current is supplied to the armature M.

The second servo drivers DS2 and DS
3, DS4, ... Control the speed of the armature M by adjusting the frequency of the three-phase AC power by the inverter circuit I, and the CPU3, ROM4, D
The A / A converter 5, the input terminal P _IN , the PWM pattern calculator 6, and the gate pulse generator 7 are provided. CP
U3 receives the output signal of the rotary encoder 2 and performs processing in accordance with the program stored in the ROM 4 to detect the magnetic pole of the magnet of the runner, and to apply the three-phase to the armature M according to the magnetic pole. Calculate the phase of the alternating current. The digital signal output by the CPU 3 is the D /
The analog signal is converted by the A converter 5 and the analog signal and the input signal input from the input terminal P _IN (the output signal output by the first servo driver DM) are converted to PW.
The PWM pattern of the three-phase AC voltage to be applied to the armature M is determined by inputting it to the M pattern calculator 6. Then, by applying the gate signal generated by the gate pulse generator 7 to the gate of the power switching element of the inverter circuit I based on the output signal of the PWM pattern calculator 6, a three-phase AC having a required frequency and amplitude is obtained. An electric current is supplied to the armature M.

Therefore, the second servo drivers DS2 and DS
The frequency and amplitude of the three-phase alternating current output by 3, DS4, ... Are substantially equal to the frequency and amplitude of the three-phase alternating current output by the first servo driver DM, and therefore the armature M,
The generated thrust forces of M, M, ... Are substantially the same, and the linear motor can be operated stably.

Further, the plurality of armatures M, M, M, ...
Since the electric power is supplied by one first servo driver DM and the plurality of second servo drivers DS2, DS3, DS4, ..., It is not necessary to increase the electric capacity of each servo driver, and By setting the same servo driver, the second servo drivers DS2, D
S3, DS4, ... Can be shared.

The second servo drivers DS2 and DS
3, DS4, ... Have the same configuration as the first servo driver DM, and may be a program in which only the program stored in the ROM 4 is changed. In this case, the first servo driver DM and the second servo driver DS2. DS3, DS4
... can be shared.

Second Embodiment FIG. 6 is a block diagram showing the configuration of the main parts of a second embodiment of the linear motor control device according to the present invention. First servo driver DM and second servo drivers DS2, DS3
A signal conversion unit F is arranged between DS4, ... FIG. 7 is a block diagram showing the configuration of the signal conversion unit F. The signal conversion unit F calculates the bandpass filter BP having a natural frequency of 22 Hz of the machine table of the article transport turntable as a pass band and its amplification factor k with respect to the total number N of servo drivers as k = N / (N-1) amplifier AMP. The signal conversion unit F is an analog circuit, and a frequency component of 22 Hz is extracted from the electric signal output from the output terminal P _OUT of the first servo driver DM by the bandpass filter BP, and the extracted frequency component is output by the amplifier AMP. N /
The signal is amplified by (N-1) times, the phase is inverted, and the obtained electric signal and the original electric signal are combined.
Other parts that are the same as those in the first embodiment are designated by the same reference numerals, and description thereof will be omitted.

The amplification factor k of the amplifier AMP is N / (N
It is not limited to -1).

The digital signal input to the D / A converter 5 of the first servo driver DM is output from the output terminal P _OUT , and the signal conversion unit F is a digital circuit, which is obtained by the signal conversion unit F. The digital signal may be input from P _IN of the second servo drivers DS2, DS3, DS4, ... And the input digital signal may be input to the D / A converter 5.

Therefore, the 22 Hz frequency component of the electrical signal output from the first servo driver DM is N / (N-
1) Doubled and this electrical signal is the second servo driver DS
2, DS3, DS4, ...

When the linear motor control device is mounted on the above-described article transport turntable device and is operated, the armatures M, M controlled by the first servo driver DM.
The generated thrust includes a frequency component of 22 Hz. Further, the thrust generated by the armatures M, M, M, ... Controlled by the second servo drivers DS2, DS3, DS4, ... Includes a component obtained by inverting the phase of the frequency component.
Resonance can be prevented by canceling each other out of these two frequency components.

FIG. 8 is a graph showing the measurement result of the amplitude characteristic of the machine base of the article conveying turntable device. Figure 8
FIG. 8A shows a case where a conventional control device is used, and FIG. 8B shows a case where the linear motor control device according to the present invention is used.
When the conventional control device is used, a large peak occurs in the vicinity of the natural frequency of the machine base, 22 Hz,
A peak also occurs near the frequency that is an integral multiple of the natural frequency. On the other hand, in the case of using the linear motor control device according to the present invention, the vibration is sufficiently damped in the vicinity of the natural frequency of the machine base and the frequency of an integral multiple thereof, and the occurrence of resonance is suppressed. There is.

[0046]

As described in detail above, according to the linear motor control method of the first invention and the linear motor control device of the third invention, the plurality of armatures of the linear motor are divided into a plurality of groups, Armatures belonging to one group are controlled by one first servo driver, and armatures belonging to another group are controlled by a plurality of second servo drivers. The first servo driver determines the traveling speed and the generated thrust of the linear motor, and supplies the alternating current whose frequency and amplitude are converted to the armatures belonging to one group. On the other hand, the second servo driver supplies AC power whose frequency and amplitude are converted according to the traveling speed and the generated thrust determined by the first servo driver to the armatures belonging to another group. Therefore, the traveling speed and the generated thrust of the linear motor used for the conversion of the frequency and the amplitude are determined only by the first servo driver, and this value is not affected by the individual difference of the servo driver. Further, since a plurality of armatures are controlled by one first servo driver and a plurality of second servo drivers, a linear motor having a plurality of armatures is used without using a servo driver having a large electric capacity. It is possible to sufficiently reduce the variation in the thrust generated by the armature in practice while controlling the.

In the case of the linear motor control method according to the second aspect of the invention and the linear motor control device according to the fourth aspect of the invention, mechanical vibrations due to thrust variation of a part of the armature controlled by the first servo driver are generated. Since the electric signal output to the second servo driver is converted by the signal conversion unit so as to be suppressed by the thrust variation of another armature controlled by the second servo driver, the occurrence of the mechanical vibration is favorably performed. It becomes possible to prevent it.

In the case of the linear motor control device according to the fifth aspect of the invention, the same frequency component as the natural frequency of the linear motor is extracted from the electric signal output from the first servo driver, the phase is inverted, and this is inverted. The original electric signal is combined and input to the second servo driver. The vibration generated from the armature controlled by the second servo driver is removed, and controlled by the first servo driver. It is possible to cancel the vibration generated from the armature.

In the case of the article conveying turntable device according to the sixth aspect of the present invention, since the linear motor control device according to the third to fifth aspects of the invention is provided, the cost is lower than that of the conventional one, but it is preferable. The present invention has an excellent effect such that the linear motor can be controlled.

[Brief description of drawings]

FIG. 1 is a partial side sectional view showing a configuration of a main part of a first embodiment of an article transporting turntable device according to the present invention.

FIG. 2 is a plan view showing a configuration of a main part of the article transporting turntable device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a main part of the first embodiment of the linear motor control device according to the present invention.

FIG. 4 is a block diagram showing a configuration of a main part of a first servo driver.

FIG. 5 is a block diagram showing a configuration of a main part of a second servo driver.

FIG. 6 is a block diagram showing a configuration of a main part of a second embodiment of a linear motor control device according to the present invention.

FIG. 7 is a block diagram showing a configuration of a signal conversion unit.

FIG. 8 is a graph showing measurement results of amplitude characteristics of a machine stand of an article transport turntable device.

FIG. 9 is a block diagram showing a configuration of a main part of a conventional linear motor control device.

FIG. 10 is a block diagram showing a configuration of a main part of a conventional linear motor control device.

FIG. 11 is a block diagram showing a configuration of a main part of a conventional servo driver.

[Explanation of symbols]

2 Rotary encoder (encoder) 3 CPU (first calculation unit, second calculation unit) 4 ROM (first calculation unit, second calculation unit) 6 PWM pattern calculator (driver) 7 Gate pulse generator (driver) R rectifier (converter) I Inverter circuit (converter) DM 1st servo driver DS2, DS3, DS4, ... Second servo driver F signal converter

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-3-93494 (JP, A) JP-A-9-121589 (JP, A) JP-A-10-304696 (JP, A) JP-A-2000-184788 (JP, A) Actual development 2-26302 (JP, U) Actual development 6-80396 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02P 7/00 H02P 5 / 00 B65G 29/00 B65G 47/80

Claims (6)

(57) [Claims] 1. A linear motor control method for controlling a linear motor having a plurality of armatures for operating one object, wherein a position of a runner of the linear motor and a magnetic pole of the runner are detected.
The position signal of the linear motor output from the encoder
The traveling speed and / or the generated thrust of the linear motor is determined by the one first servo driver which performs feedback control based on the frequency, and the frequency corresponds to the determined traveling speed and / or the amplitude corresponds to the determined generated thrust.
The first alternating current is supplied to a part of the armature, and an analog signal corresponding to the traveling speed and / or the generated thrust is output to one or a plurality of second servo drivers, and the traveling speed is generated by the second servo driver. And / or an amplitude corresponding to the generated thrust and
Calculated according to the magnetic pole of the runner detected by the encoder
A method of controlling a linear motor, comprising supplying a second AC current having a phase to another armature. 2. The second servo driver supplies the alternating current to the other armature in order to remove vibration of a predetermined frequency from the generated thrust of the armature supplied with the alternating current by the first servo driver. The method of controlling a linear motor according to claim 1, wherein the frequency and / or the amplitude of the generated alternating current is determined. 3. A linear motor control device having a plurality of armatures for controlling a linear motor for operating one object, comprising: an encoder for detecting a position of a runner of the linear motor and a magnetic pole of the runner ; A first converter for converting the frequency and / or the amplitude of the alternating current; a first arithmetic unit for calculating the deviation between the position of the linear motor detected by the encoder and a target position given in advance;
The second calculation unit for calculating a frequency and / or amplitude of the alternating current to be supplied to the armature of the linear motor according to a result of said first operation unit has been calculated, according to a result of said second arithmetic unit is calculated A first driver for driving the first converter ; and
An analog signal corresponding to the result calculated by the second arithmetic unit is
A first servo driver having an output terminal for outputting, a second converter for converting the frequency and / or the amplitude of the alternating current, and a second servo driver according to the magnetic pole of the runner detected by the encoder.
2 Calculate the phase of the alternating current that should be output from the converter
Means, an input terminal for inputting the analog signal, and a front
The second converter is driven based on the phase and the analog signal.
A second servo driver having a moving second driver, and a controller for a linear motor. 4. The other armature is driven so that the alternating current whose frequency and / or amplitude is converted by the second servo driver cancels the vibration of a predetermined frequency from the thrust generated by the part of the armature. 4. A signal conversion unit that converts the analog signal output from the first servo driver to the second servo driver in order to generate an alternating current that is provided between the first servo driver and the second servo driver. Linear motor controller. 5. The signal conversion unit comprises a bandpass filter for a passband including the predetermined frequency, and inverts the phase of the signal output by the bandpass filter to obtain an output signal of the first servo driver. The control device for the linear motor according to claim 4, wherein the control is performed. 6. An article-conveying turntable device comprising a linear motor having a plurality of armatures, the table body being rotated by the linear motor, according to claim 3. An article-conveying turntable device comprising a linear motor control device.