JP2000175497A - Device and method for controlling pulse motor and recording medium with pulse motor control program recorded therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To positively enable a pulse motor controller used for production facilities, robots, etc., to detect the stepping out of a pulse motor without requiring expensive step-out detectors. SOLUTION: A pulse motor controller is constituted in a way such that the controller is provided with a detector, having such a simple constitution in that the detector can be actuated by the fixed action of a load, inputs the output signal of the detector to first and second memory circuits 12 and 13 via an input circuit 14, and stores the value counted, based on the variation of input signals from a pulse-counting circuit 10 which counts pulse trains outputted to a pulse motor drive device 2 and the detector in the memory circuits 12 and 13. The controller also detects the stepping-out state of a pulse motor, by comparing the current stored value with the preceding stored value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse motor control apparatus, a pulse motor control method, and a pulse motor control method for detecting a step-out state of a pulse motor used for position control and speed control in a production facility or a robot. The present invention relates to a recording medium on which a pulse motor control program for detecting an adjustment state is recorded.

[0002]

2. Description of the Related Art A pulse motor used for position control and speed control has a structure in which a rotation angle and a rotation speed are determined in accordance with an input pulse, and therefore, it is generally controlled in an open loop. However, in a device using a pulse motor, an unusual work such as an abnormal work being sent as a control target, a foreign object adhering to a movable portion, or a breakage of a mechanical portion occurred. At this time, a load fluctuation may occur, and the pulse motor may not be able to respond to the input pulse. In this manner, a phenomenon in which the pulse motor cannot respond to the input pulse due to unpredictable load fluctuation or the like and becomes uncontrollable is called step-out. However, in a pulse motor under open loop control, since there is no feedback information from the pulse motor, even if the pulse motor loses synchronism due to a load change or the like, the loss of synchronism could not be detected. Therefore, in the conventional pulse motor control device, the actual rotational position of the pulse motor is detected to detect the step-out state of the pulse motor.

The configuration of a conventional pulse motor control device having a step-out state detecting function will be described below with reference to FIGS. FIG. 5 is a block diagram showing an overall configuration of a conventional pulse motor control device. FIG. 6 shows a configuration of a pulse generation device in a conventional pulse motor control device, and shows an example of a connection state between the pulse generation device, the pulse motor drive device, and the rotary operation converter. 5 and 6, the microprocessor 107 of the pulse generator 101 generates a pulse based on position data, velocity data, acceleration data, and a signal from the position detector 105 that detects the position of the load 104. An operation command for driving the motor 103 is calculated. The pulse generation circuit 108 generates a pulse train of an operation command of the pulse motor 103 and outputs the pulse train to the differential output circuit 109. The differential output circuit 109 converts a pulse signal reciprocating at a constant voltage into two signals having different potentials, and outputs the two signals to the pulse motor driving device 102. The pulse motor driving device 102 receives a pulse train of an operation command output from the pulse generator 101, and controls the pulse motor 1 to be controlled.
The pulse motor 103 is driven and controlled by calculating a current flowing through each phase of the pulse motor 103.

The load 104 shown in FIG. 5 is a rotary plate whose rotation is controlled by a pulse motor 103, a table whose movement is controlled, or the like. The position detector 105 is a sensor for detecting the position of the load 104,
4 is provided so as to limit the movement of the moving member 4 from exceeding a predetermined moving range. The rotary motion converter 115 provided on the rotation axis of the pulse motor 103
3 detects the rotational position of the rotating shaft, and generates a pulse
Feedback. As the rotation operation converter 115, an encoder, a resolver, or the like is used. The encoder serving as the rotary motion converter 115 detects a slit formed in a disk or the like using light or electromagnetic means, and
This is a detector that outputs two pulse trains of the A phase and the B phase which are shifted in phase by 0 degrees. The resolver as the rotary motion converter 115 has two-phase windings orthogonal to each other on the stator,
A control transformer having a single-phase winding or an orthogonal two-phase winding on the rotor, and applying a two-phase AC voltage to the stator winding to apply a sin component of the rotor angle to the rotor winding, co
Since a voltage proportional to the s component is generated, the position is determined from the relationship. Rotational motion converter 115 in FIG.
The encoder outputs two pulse trains of phase A and phase B, which are 90 degrees out of phase, and detects the rotational position of the pulse motor 103 from the rotary operation converter 115. The phase and B-phase pulses are counted and obtained.

In FIG. 6, a differential input circuit 117 is a conversion circuit for an electric signal, and the A-phase (A, A,
The two sets of signals of a) and B phase (B, b) are converted into pulse signals that reciprocate between fixed voltages. The position count circuit 116 counts the pulse signals output from the differential input circuit 117, and represents the count value (position information) with necessary bits. The pulse generation circuit 108 generates a pulse signal (movement amount information) having a value set by the microprocessor 107.
Is converted into a pulse train having a constant period. Differential output circuit 109
Converts two signals having different potentials into a pulse signal that reciprocates between fixed voltages, contrary to the differential input circuit 117 described above.

As shown in FIG. 6, two sets of signals CW and c are sent from a differential output circuit 109 to a pulse motor drive circuit 102.
w, CCW and ccw are output. In this signal,
CW represents a pulse signal of a signal indicating a clockwise rotation command of the pulse motor, and cw is a pair of differential signals that become L level when the CW signal is H level and become H level when the CW signal is L level. CCW represents a pulse signal indicating a counterclockwise rotation command, and ccw is a pair of differential signals that go low when the CCW signal is high and high when the CCW signal is low. The pulse count circuit 110 receives the pulse signal from the pulse generation circuit 108 and
Position command information of about 6 bits to about 32 bits is generated. The comparison circuit 111 receives the position command information from the pulse count circuit 110 and the position information from the position count circuit 116, and compares the position command information with the position information.

Next, the operation of the conventional pulse motor control device will be described. In FIG. 6, two types of signals of the A-phase and the B-phase output from the rotary motion converter 115 are:
Each of the signals is converted into a pulse signal by the differential input circuit 117 and input to the position count circuit 116. The position count circuit 116 converts the input A-phase and B-phase signals from 16 bits to about 32 bits of position information.

On the other hand, the pulse generating circuit 108 generates a pulse signal having a value set by the microprocessor 107 at a constant period. The pulse signal from the pulse generation circuit 108 is input to the differential output circuit 109, and outputs a pulse train of a driving command to be output to the pulse motor driving device 102. The pulse signal generated by the pulse generation circuit 108 is simultaneously input to the pulse count circuit 110, and is converted by the pulse count circuit 110 from 16 bits to about 32 bits of position command information. The position command information and the position information are input to the comparison circuit 111, respectively, and the result of comparing the two values is input to the microprocessor 107. When the position command information and the position information do not match, the microprocessor 107 determines that the pulse motor is out of step. As described above, the conventional pulse motor control device is provided with the pulse processing circuit such as the position count circuit 116 and the differential input circuit 117 for processing the pulse signal output from the rotary motion converter 115. In the conventional pulse motor control device, step-out is performed by providing a pulse processing unit and a comparison unit for comparing position command information and position information inside the microprocessor 107 without providing the comparison circuit 111. Some devices were configured to detect the state.

[0009]

As described above, in the configuration of the conventional pulse motor control device, it is necessary to provide a rotary motion converter such as an encoder or a resolver in order to detect a step-out state of the pulse motor. In addition, a pulse processing circuit or a pulse processing means having a function for processing a signal from the rotary motion converter must be provided, and there has been a problem that the apparatus is expensive and cannot be miniaturized. further,
Since a rotary motion converter with the same resolution must be installed according to the type of position resolution of the pulse motor to be used, various rotary motion converters, etc. had to be prepared according to the specifications of the pulse motor. . The present invention records a pulse motor control device, a pulse motor control method, and a control program capable of reliably detecting a step-out state of a pulse motor without providing an expensive rotary motion converter such as an encoder or a resolver. It is intended to provide a recording medium.

[0010]

In order to achieve the above object, a pulse motor control device according to the present invention operates based on position data, speed data, and acceleration data designated in advance for driving a pulse motor. A pulse generation circuit for generating a command pulse train; a detector for detecting a constant operation of a load driven by the pulse motor; a pulse count circuit for counting a pulse train output by the pulse generation circuit; A first memory for storing a value counted by the pulse count circuit based on a signal output when the constant operation of
When the memory stores the count value of the pulse count circuit, the second memory stores the previous count value stored in the first memory, the first memory and the second memory. A comparison circuit that compares the stored count values; and a processing unit that detects a step-out state of the pulse motor based on an output signal of the comparison circuit. According to the present invention configured as described above,
By storing the count value of the pulse train when the load performs a constant operation and comparing the count value with the previous count value, the step-out state of the pulse motor can be reliably detected.

According to the pulse motor control method of the present invention, a position data specified in advance for driving a pulse motor is provided.
Generating a pulse train of an operation command based on speed data and acceleration data; counting pulses of the pulse train; detecting a constant operation of a load driven by the pulse motor; Storing, in a first memory, a count value of the pulse train when an operation is detected; and, when the first memory stores the count value, a previous count value stored in the first memory. Is stored in a second memory; the step of comparing the respective count values stored in the first memory and the second memory; and the stepping motor of the pulse motor based on a result of the compared count value. Detecting a step-out state. According to the present invention configured as described above, it is possible to reliably detect a step-out state by counting a pulse train when a constant operation of a load is detected and comparing the count value with a previous count value. Can be.

A recording medium on which a control program according to the present invention is recorded includes a step of generating a pulse train of an operation command based on position data, speed data and acceleration data designated in advance for driving a pulse motor; Counting a pulse, a step of storing a count value of the pulse train in a first memory when a constant operation of a load driven by the pulse motor is detected, and a step in which the first memory stores the count value in the first memory. When storing, the procedure of storing the previous count value stored in the first memory in the second memory is compared with the respective count values stored in the first memory and the second memory. And causing the computer to execute a step of detecting a step-out state of the pulse motor based on a result of the compared count value. According to the present invention configured as described above, the recording medium on which the control program is recorded is supplied to the computer, and the computer reads out and executes the control program recorded on the recording medium, whereby the step-out of the pulse motor is performed. A condition is detected.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a pulse motor control device and a pulse motor control method according to the present invention will be described below with reference to FIGS.

Embodiment 1 FIG. 1 is a diagram showing a configuration of a pulse motor control device according to Embodiment 1 of the present invention. FIG. 2 is a block diagram illustrating a configuration of a pulse generator in the pulse motor control device according to the first embodiment. FIG.
In FIG. 2 and FIG. 2, the pulse generator 1 is a control device that generates a pulse train of an operation command of the pulse motor 3. The processing circuit 7 in the pulse generator 1 calculates an operation command for driving the pulse motor 3 based on the position data, speed data, acceleration data, signals from the position detector 5 and the like specified in advance. The pulse generation circuit 8 generates a pulse signal (movement amount information) having a value set by the processing circuit 7 composed of a microprocessor at a constant period.
The differential output circuit 9 converts a pulse signal reciprocating between fixed voltages into two signals having different potentials.

As shown in FIG. 2, two sets of a total of four signals CW, c are sent from the differential output circuit 9 to the pulse motor driving device 2.
w, CCW and ccw are output. In this signal,
CW indicates a pulse signal of a signal indicating a clockwise rotation command as viewed from the axis side of the pulse motor, and cw indicates that the CW signal is H
It is a pair of differential signals that are at L level when at level and at H level when at L level. CCW represents a pulse signal indicating a counterclockwise rotation command, and ccw is a pair of differential signals that go low when the CCW signal is high and high when the CCW signal is low. The pulse motor driving device 2 receives a pulse train of an operation command output from the pulse generation device 1, calculates a current flowing in each phase of the pulse motor 3 to be controlled, and controls the driving of the pulse motor 3. In the first embodiment, the load 4 is a rotary plate whose rotation is controlled by the pulse motor 3 or a table whose movement is controlled.

The plurality of position detectors 5 are sensors for detecting the position of the load 4, and are preferably photoelectric sensors or proximity sensors, and regulate the position so that the load 4 does not exceed a predetermined moving range. It is provided for. The step-out detection detector 6 detects a step-out state of the pulse motor 3, and is preferably a photoelectric sensor or a proximity sensor.
The load 4 is fixed at a predetermined position in order to detect a specific moving position of the load 4 within a predetermined range of the rotational movement or the reciprocating movement. In FIG. 2, the input circuit 14
Outputs a detection signal from a sensor which is a step-out detection detector 6 to the first memory circuit 12 and the second memory circuit 13. The pulse count circuit 10 receives the pulse signal from the pulse generation circuit 8, generates position command information of about 16 to 32 bits, and outputs the position command information to the first memory circuit 12. The first memory circuit 12 and the second memory circuit 13 are formed by being divided into different areas in the same storage device.

Next, the operation of the pulse motor control device according to the first embodiment will be described. The pulse generator 1 performs a calculation based on position data, speed data, acceleration data, position data from a position detector 5 attached to the load 4, and the like, and generates a pulse train of an operation command for the pulse motor 3. appear. The pulse motor driving device 2 receives a pulse train (CW, cw, CCW, ccw) of the operation command output from the pulse generation device 1, calculates a current flowing through each phase of the pulse motor 3, and controls the current to control the current. Is driven. The out-of-step detection detector 6 is a sensor that detects an operation when the load 4 performs a predetermined rotational motion or a reciprocating motion,
Specifically, it is a position sensor that detects a position when the load 4 performs a certain operation. This step-out detection detector 6
Is mounted so as to operate when the load 4 performs a constant operation, and outputs a detection signal to the pulse generator 1 when the constant operation of the load 4 is detected.

The out-of-step detection detector 6 of the first embodiment detects out-of-step of the pulse motor 3, and a signal from the out-of-step detection detector 6 is input to the input circuit 14. The input circuit 14 inputs a signal from the step-out detection detector 6 to the first memory circuit 12 and the second memory circuit 13. At this time, the first memory circuit 12 stores the pulse count value which is the position command information converted by the pulse count circuit 10, and the second memory circuit 13 stores the pulse count value immediately before being stored in the first memory circuit 12. Is stored. The comparison circuit 11 receives the pulse count value of the position command information stored in the first memory circuit 12 and the second memory circuit 13 and compares the two values. Example 1
It is not necessary to specify the format of the data of the position command information in, and any digital data may be used. For example, if it is 16 bits, 8000h to 7FFFh (16
Range can be counted. (This is 1
When represented by a decimal number, it corresponds to the range of -32,768 to +32,767. With 32 bits, the range is 65,536 times the value of 16 bits.

Next, a comparison operation in the pulse generator 1 according to the first embodiment will be described. The signal output from the step-out detection detector 6 is directly passed through the input circuit 14 to the first signal.
Of the memory circuit 12 and the second memory circuit 13. When the out-of-step detection detector 6 detects a predetermined operation of the load, the out-of-step detection detector 6 switches the signal output to the input circuit 14 from L level to H level (or from H level to L level). . The position command information of the pulse count circuit 10 is stored in the first memory circuit 12 every time the signal is switched in this manner. The position command information is stored in the first memory circuit 12 and at the same time, the contents stored in the first memory circuit 12 up to that time are stored in the second memory circuit 13. As described above, the previous position command information stored in the second memory circuit 13 and the current position command information stored in the first memory circuit 12 are compared in the comparison circuit 11, and the comparison result of the two values is compared. Is input to the processing circuit 7 which is a microprocessor. Processing circuit 7
Compares the value of the previous position command information stored in the second memory circuit 13 with the value of the current position command information stored in the first memory circuit 12, and if the values are different, the pulse motor 3 When it is determined that the motor is out of step, the pulse generator 1 outputs a signal indicating the out-of-step state of the pulse motor 3.

In the pulse motor control device according to the first embodiment, when comparing the pulse count value as the position command information, there is actually a delay of the signal and the like. Is provided as appropriate.
It should be noted that the attachment position of the step-out detection detector 6 may be configured so as to operate within the operation range of the load 4, and the position is not particularly limited. In the first embodiment, the first memory circuit 12 operates in the initial state and when the out-of-step detection detector 6 first detects the movement of the load 4 to the predetermined position.
And the contents stored in the second memory circuit 13 may be different from each other. In this case, the comparison result is ignored, and the step-out is performed after the second time or after the comparison result matches. It is configured to start a state detection operation. The pulse motor control device according to the first embodiment configured as described above can reliably detect a step-out state of the pulse motor.

Embodiment 2 Next, a pulse motor control device according to Embodiment 2 of the present invention will be described with reference to the accompanying drawings. FIG. 3 is a block diagram illustrating a configuration of a pulse motor control device according to a second embodiment, which is one embodiment of the present invention. FIG. 4 is a flowchart of pulse motor control in the pulse motor control device according to the second embodiment.
In FIG. 3, components having the same functions and configurations as those of the first embodiment are denoted by the same reference numerals, and the description of the first embodiment is referred to, and the detailed description is omitted. In FIG. 3, a detection signal output from the step-out detection detector 6 is input to a microprocessor 18 via an input circuit 14, and the microprocessor 18 stores position command information when the detection signal is input. The pulse motor, the load, and the various position detectors are connected to the pulse generator 1 and the pulse motor driver 2 as in the first embodiment.

Next, the operation of the pulse generator 1 in the pulse motor control device according to the second embodiment will be described with reference to the flowchart of FIG. The pulse generation circuit 8 generates a pulse signal having a value set in the microprocessor 18 at a constant period, and the generated pulse train is output to the differential output circuit 9.
To the pulse motor driving device 2 through Also,
The pulse signal generated by the pulse generation circuit 8 is input to the pulse count circuit 10 at the same time. The input pulse signal is converted by the pulse count circuit 10 from 16 bits to 32 bits.
It is converted into bit-wise position command information. The format of the data of the position command information does not need to be particularly specified, and may be digital data. For example, a range of 8000h to 7FFFh (hexadecimal notation) can be counted with 16 bits. (This corresponds to the range of -32, 768 to +32, 767 in decimal notation. For 32 bits, the range is 65,536 times the value of 16 bits.)

The signal output from the out-of-step detection detector 6 is directly transmitted to the microprocessor 18 via the input circuit 14.
Is input to When the out-of-step detection detector 6 detects a predetermined operation of the load 4, the out-of-step detection detector 6 outputs the input circuit 14
Changes from the L level to the H level (or from the H level to the L level). When the detection signal of the out-of-step detection detector 6 is input to the microprocessor 18, the microprocessor 18 starts interrupt processing,
The pulse count value of the pulse count circuit 10 is read (step 1), and the read pulse count value is stored in a first memory in the microprocessor 18 (step 2). If this interrupt processing is the first operation,
The interrupt process at this time is ignored, and the process waits until the next interrupt process (step 3). In the second and subsequent interrupt processing, the pulse count value of the pulse count circuit 10 at that time is stored in the first memory. The microprocessor 18 holds the difference between the previous position command information stored in the second memory and the current position command information stored in the first memory (step 4). The absolute value of the difference between the held position command information is defined as DEF. Next, the pulse count value stored in the first memory is stored in the second memory (step 5).

The absolute value of the difference between the held position command information (D
EF) is compared with a predetermined step-out detection reference value, and it is determined whether or not the absolute value of the difference between the position command information difference (DEF) and the step-out detection reference value is smaller than an allowable value. (Step 6). In step 6, when the absolute value of the difference between the position command information difference (DEF) and the step-out detection reference value is smaller than the allowable value, it is determined that there is no step-out,
The step-out detection process ends, and the process returns to the main process of the microprocessor 18. Conversely, the absolute value (DE
If the absolute value of the difference between F) and the step-out detection reference value is larger than the allowable value, it is determined that step-out has occurred, and step-out detection processing is performed.
When the stepping out of the pulse motor 3 occurs, the first memory stores a pulse count value different from the position command information that should be stored originally. In the second embodiment, the difference between the absolute value (DEF) of the difference between the pulse count values stored in the first memory and the second memory and the absolute value of the step-out detection reference value is compared with an allowable value. Out-of-step is detected. At this time,
The microprocessor 18 is performing other processing, and the priority of the step-out detection interrupt is set as high as possible so that the step-out detection processing is not missed.

The position at which the step-out detecting detector 6 is mounted is not particularly limited as long as it operates within the operating range of the pulse motor. ROM, R
Using a microcomputer with a built-in AM simplifies the configuration. Further, if a microprocessor having a built-in counter in a microcomputer having a built-in ROM and RAM is used as the microprocessor, the configuration is further simplified. Note that the pulse motor control device in the above-described embodiment can change the setting even when the load, position control, speed control, and the like by the built-in production system, robot, and the like are different. Further, in the pulse motor control device of the above-described embodiment, since various settings need to be changed for the data format and the data amount such as the position command information and the required resolution of the position information, the software It is configured so that the system can be constructed by changing the settings of the software or by rewriting the software itself. Further, the pulse motor control method shown in the above-described embodiment can be programmed into a computer, and the setting can be changed according to expansion / reduction of the system and various systems. In this case, the computer program is recorded on a recording medium such as a floppy disk, a CD-ROM, a DVD (digital versatile disk), a magneto-optical disk, and a removable hard disk. It is possible to achieve the effect of

[0026]

According to the present invention, the pulse train output to the pulse motor driving device is counted, and the count value stored in the same operation as the previous operation is compared with the newly stored count value, thereby enabling the pulse motor to operate. A pulse motor control device and a pulse motor control method capable of reliably detecting a step-out state can be obtained. According to the present invention, there is provided a pulse motor control device and a pulse motor control method capable of reliably and highly accurately detecting a step-out state of a pulse motor without providing an expensive rotary motion converter such as an encoder or a resolver. Obtainable. Since the pulse motor control method of the present invention can be computer-programmed, it is possible to record the pulse motor control method on a recording medium and implement pulse motor control that can reliably detect the step-out state of the pulse motor. It is.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a pulse motor control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a pulse generation device of the pulse motor control device according to the first embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of a pulse generator of a pulse motor control device according to a second embodiment of the present invention.

FIG. 4 is a flowchart illustrating a pulse motor control method in the pulse motor control device according to the second embodiment of the present invention.

FIG. 5 is a diagram showing a schematic configuration of a conventional pulse motor control device.

FIG. 6 is a block diagram showing a configuration of a conventional pulse motor control device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pulse generator 2 pulse motor driver 3 pulse motor 4 load 5 position detector 6 out-of-step detection detector 7 processing circuit 8 pulse generator 9 differential output circuit 10 pulse count circuit 11 comparison circuit 12 first memory circuit 13 Second memory circuit 14 Input circuit

Claims (4)

[Claims] 1. A pulse generation circuit for generating a pulse train of an operation command based on position data, speed data, and acceleration data designated in advance for driving a pulse motor, and a constant operation of a load driven by the pulse motor. A detector for detecting; a pulse count circuit for counting a pulse train output from the pulse generation circuit; and a value counted by the pulse count circuit based on a signal output when the detector detects a constant operation of the load. A first memory, a second memory that stores a previous count value stored in the first memory when the first memory stores a count value of the pulse count circuit, the first memory And a comparison circuit for comparing each count value stored in the second memory with the output signal of the comparison circuit. The pulse motor control apparatus characterized by comprising a processing means for detecting an out-of the pulse motor. 2. The pulse motor control device according to claim 1, wherein said first and second memories are formed in different areas in the same storage device. Generating a pulse train of an operation command based on position data, speed data, and acceleration data designated in advance to drive the pulse motor; counting the pulses of the pulse train; driving by the pulse motor Detecting the constant operation of the load to be performed; and storing the count value of the pulse train in the first memory when the constant operation of the load is detected; and when the first memory stores the count value. , The previous count value stored in the first memory is stored in a second
A step of storing the count values stored in the first memory and the second memory; and a step-out state of the pulse motor based on a result of the compared count values. Detecting the pulse motor. 4. A step of generating a pulse train of an operation command based on position data, speed data, and acceleration data designated in advance for driving the pulse motor, a step of counting pulses of the pulse train, and a step of driving by the pulse motor. Storing a count value of the pulse train in a first memory when detecting a constant operation of a load to be performed; and storing the count value in the first memory when the first memory stores the count value. Second count value from previous
A step of storing the count values stored in the first memory and the second memory, and a step-out state of the pulse motor based on a result of the compared count values. A recording medium on which a pulse motor control program for causing a computer to execute a detection procedure is recorded.