JPH09131085A - Position detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To calculate a life of a motor accurately by calculating an estimated life of the motor based on load information from a load detecting means and driving time information from a driving time detecting means. SOLUTION: An estimated life of a serve motor 3 is estimated by the average input time of rotations based on driving time information and load information, the average executive torque, the rated torque of the servo motor 3, the rated number of rotations of the motor, and an expected life when the servo motor 3 is used with the rated torque and the rated number of rotations. In this case, the average input number of rotations is found from the amount of movement of the motor per one processing cycle and the time of one cycle, which are found from the processing cycle based on a command calculated by a motor rotational speed calculating means 4 in a position detector 4A and a rotational speed of the processing cycle. The averate executive torque is found from the amount of movement of the motor per one processing cycle and motor torque at such a processing cycle that the same command may be input into the serve motor 3. As a result, an accurate estimated life of the motor can be calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detector for detecting the rotational position of a motor.

[0002]

2. Description of the Related Art FIG. 10 is a block diagram showing an example of the configuration of a conventional positioning device and position detector.
In the figure, 1 is a positioning device, 2 is a servo amplifier, 3
Is a servo motor, 4 is a position detector connected to the servo motor 3, 5 is an external sensor, 6 is an external input device connected to the positioning device 1, and 7 is an external output device similarly connected to the positioning device 1. is there.

The positioning device 1 has a communication means 11 for performing serial communication with the servo amplifier 2, a sensor signal detection means 12 for detecting a sensor input signal from an external sensor 5,
External signal input means 13 for inputting an external input signal from the external input device 6, external signal output means 14 for outputting an external output signal to the external output device 7, and a timer counter 15 reset at each internal processing cycle of the positioning device 1. , A sensor input timer counter 16 that copies the timer counter 15 at the moment when the sensor detection signal is input from the sensor signal detection means 12, and a machine position at the moment when the sensor input signal from the external sensor 5 is detected (rotation of the servo motor 3). It is composed of a position calculating means 17 at the time of sensor input for calculating (position).

The servo amplifier 2 is connected to the communication means 11 and has a communication means 21 for performing serial communication with the positioning device 1, a motor rotation speed calculation means 22, and an allowable motor rotation speed in which an allowable rotation speed of the servo motor 3 is set in advance. Motor rotation position for parallel input of the pulse P generated by the speed storage memory 23, the overspeed monitoring means 24 of the servomotor 3, and the motor rotation pulse generator 41 inside the position detector 4 in accordance with the rotation of the servomotor 3 and counting up. Detection means 2
5, it is composed of a motor use accumulated time storage memory 26.

Next, the operation will be described. First, the operation of checking the life of the servomotor 3 will be described. In the motor that drives the machine, the life time of the servo motor 3 is estimated on the assumption that the motor rotates at a constant speed. Therefore, in the conventional determination of the life of the motor (generally, it can be rephrased as the life of the bearing mounted to smooth the rotation of the motor shaft), the operating condition (speed) of the motor is kept constant. There is a method of determining the life of the motor by comparing the previously calculated life time with the cumulative time for cumulatively storing the time when the motor is actually driven. Normally, the servo amplifier 2 is processed in a constant cycle for controlling the servo motor 3. Therefore, the energization time of the servo motor 3 is detected by multiplying the counter value counted up at regular intervals of the servo amplifier 2 by the time of the processing cycle of the servo amplifier 2, and this value is stored in the motor usage accumulated time storage memory 26. The cumulative use time of the servo motor 3 is additionally stored. The operator uses the accumulated motor time storage memory 2
While monitoring the value of 6, the judgment was made by comparing with the expected life time calculated in advance assuming that the use condition of the servomotor 3 is constant.

Next, the operation for detecting the motor rotation position of the servo motor 3 will be described. The motor rotation pulse generator 41 inside the position detector 4 generates a pulse P generated by the rotation of the servo motor 3. This pulse P is transmitted to the motor rotational position detecting means 25 inside the servo amplifier 2 by parallel transmission, and the pulse P transmitted there is counted. The count value counted by the motor rotation position detecting means 25 is communicated by the communication means 21 of the servo amplifier 2 via the communication line to the communication means 11 of the positioning device 1.
Is output to the timer counter 15. In the positioning device 1, the servo amplifier 2 to the timer counter 15
The motor rotation position of the servo motor 3 is detected based on the count value input to the servo amplifier 2, the speed F commanded to the servo amplifier 2, the tamari pulse PC, and the like. Further, when continuously obtaining the motor rotation position of the servo motor 3, the above processing is repeated.

Next, during automatic operation or the like of the machine such as the servomotor 3 or the like, a request to receive a sensor input signal from the external sensor 5 to the positioning device 1 and obtain the motor rotation position of the servomotor 3 at that moment. The operation when there is a description will be described. Sensor signal detection means 1 of the positioning device 1
In 2, when the sensor input signal from the external sensor 5 is detected, the sensor signal detection means 12 outputs the sensor detection signal to the sensor input timer counter 16. Upon receiving the sensor detection signal, the sensor input timer counter 16 copies the count value of the timer counter 15,
The value t is output to the position calculation means 17 at the time of sensor input. In the position calculation means 17 at the time of sensor input, the value t from the sensor input timer counter 16, the speed F commanded to the servo amplifier 2 at that time, the motor rotation position of the servo motor 3 at that time, and the servo amplifier 2 are calculated. The machine position at the time of sensor input is calculated by the following calculation formula from the Tamari pulse PC. PA = PB + t x F-PC PA: Motor rotation position at sensor input PB: Command motor rotation position in the processing cycle immediately before sensor input PC: Tally pulse t: Timer counter at sensor input F: Command speed

Next, the operation relating to the monitoring of the servo motor 3 will be described. Normally, the servomotor 3 has an allowable rotation speed per unit time (hereinafter referred to as an allowable rotation speed).
Is the memory 2 for storing the allowable motor rotation speed of the servo amplifier 2.
The servo amplifier 2 connected to the servo motor 3 must monitor the rotation speed of the servo motor 3 so that the rotation speed of the servo motor 3 does not exceed the predetermined allowable rotation speed while the motor is rotating. is there. Normally, the rotational speed of the servomotor 3 is calculated by calculating the difference between the rotational position A counted by the motor rotational position detection means 25 with the pulse P and the rotational position B in the previous processing cycle by the motor rotational speed calculation means 22. Then, the actual rotation speed of the servo motor 3 is obtained. By comparing the actual rotation speed obtained by this calculation with the allowable rotation speed preset in the motor allowable rotation speed storage memory 23, the rotation speed of the servo motor 3 does not exceed the allowable rotation speed. I'm watching.

[0009]

In the conventional detection device as described above, the service life of the servo motor 3, that is, the bearing is determined only by the energization time to the servo motor 3 under a certain condition. However, the factors that affect the life of the servomotor 3 are not only the energization time, but also many factors such as the rotation speed of the motor shaft, temperature, and load. Therefore, considering that there are various states such as when the motor shaft is not rotating even when the motor is energized or is rotating at high speed, and the load changes further, the servo motor can be operated only by the energizing time of the motor. When judging the life of No. 3, there was a problem that the life could not be accurately judged and an error was large.

Further, when the positioning device 1 tries to obtain the motor rotational position of the servo motor 3, generally, the positioning device 1 has to perform a large amount of processing,
A lot of load is applied to the positioning device 1, and the detection cycle for the positioning device 1 to detect the motor rotation position of the servo motor 3 receives data from the position detector 4 to the positioning device 1 via the servo amplifier 2. There is a problem that it becomes longer than the processing cycle (detection cycle) for serial transmission (the detection cycle is rough), and even if a detailed motor rotation position of the servo motor 3 cannot be obtained due to the roughness of the detection cycle. .

Further, the servo amplifier 2 to the positioning device 1
Since the data for detecting the motor rotation position is serially transmitted to the servo amplifier 2 via the communication line, the position command output by the positioning device 1 to the servo amplifier 2 and the position command output by the servo amplifier 2 from the servo motor 3 are transmitted. There is a gap in time. Further, the movement amount of the servo motor 3 during the processing cycle is based only on the rotation speed (command speed F) of the servo motor 3 commanded from the positioning device 1, and the sensor input signal is input from the external sensor 15. An error is included in the actual rotation speed of the servo motor 3 at the instant. Therefore, there is another problem that the actual rotational position (mechanical position) of the servo motor 3 at the moment when the sensor input signal from the external sensor 5 is calculated based on these data is inaccurate. .

Further, in the servo amplifier 2, when the motor rotation position of the mechanism (portion) that expands and contracts due to load, temperature, etc. is detected, correction based on load, temperature, etc. cannot be performed, and the accurate servo motor 3 However, there is a problem in that the motor rotation position cannot be detected.

Further, the servomotors 3 that can be connected to the servo amplifier 2 may have different rated speeds.
Therefore, in order to monitor whether or not the rotation speed of the servo motor 3 exceeds the allowable rotation speed of the servo motor 3, the allowable rotation speed of the servo motor 3 is set in the servo amplifier 2 connected to the servo motor 3. It is necessary to manually check the type of the servo motor 3 and manually input the allowable rotation speed of the servo motor 3 when setting the allowable rotation speed in the servo amplifier 2. If set, there is a problem that the motor overspeed cannot be monitored.

The present invention has been made to solve the above problems, and a first object thereof is to obtain a position detector capable of accurately calculating the life of a motor. A second object is to obtain a position detector which the position detector itself can obtain by internal calculation without the positioning device detecting the rotational position of the motor based on the data output by the position detector. . Further, a third object is to obtain a position detector capable of further detecting the rotational position of the motor and detecting the detailed rotational position. A fourth object is to obtain a position detector which can detect an accurate motor rotation position when a sensor signal is input. A fifth object is to obtain a position detector capable of correcting the load, temperature and the like when detecting the motor rotation position of the servo amplifier and detecting the accurate motor rotation position. Further, a sixth object is to obtain a position detector capable of monitoring the rotation speed of the motor based on the preset allowable rotation speed without setting and monitoring the allowable rotation speed of the servo motor by the servo amplifier. That is.

[0015]

In a position detector according to the present invention, a drive time detecting means for detecting a drive time of a motor driven based on a command, a load detecting means for detecting a load applied to the motor, Estimated life calculation means for calculating the estimated life of the motor based on the load information from the load detection means and the drive time information from the drive time detection means.

Further, pulse generating means for oscillating pulses according to the driving of the motor driven based on the instruction output from the command device through the communication line, the counting result of the pulses oscillated from the pulse generating means, and the above-mentioned instruction. Rotation position detecting means for calculating the rotation position of the motor based on the position, and the rotation position of the motor calculated by the rotation position detecting means is transmitted to the command device.

Further, a memory means for holding a plurality of rotational positions of the motor calculated by the rotational position detecting means is provided.

Further, a sensor signal detecting means to which an external sensor is connected is provided, and when the sensor signal detecting means detects a sensor input signal from the external sensor, the rotational position detecting means calculates the rotational position of the motor. It was done like this.

Further, based on the allowable rotation speed storage memory for storing in advance the allowable rotation speed determined for each motor, and the change amount of the rotation position of the motor detected by the rotation position detecting means, the rotation speed of the motor is determined. Based on the rotation speed calculation means for calculating, the rotation speed of the motor calculated by the rotation speed calculation means and the allowable rotation speed stored in the allowable rotation speed storage memory, the rotation speed of the motor is the allowable rotation speed. And a monitoring means for monitoring the motor so as not to exceed the limit.

Further, there is provided a correcting means for correcting the pulse oscillated by the pulse generating means in accordance with the driving of the motor based on the external condition due to the temperature or load of the motor.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a block diagram of an embodiment of a positioning device and a position detector according to the present invention. In the figure, 1 is a positioning device as a command device for outputting a command, 2A is a servo amplifier similarly as a command device, 3 is a servo motor, and 4A is a position detector.

The servo amplifier 2A has a communication means 21 for performing serial communication with the positioning device 1, a communication means 21a for performing serial communication with the position detector 4A, and a current value fed back from the servo motor 3. Divide by the rated current value and the value of the rated torque TR of the servo motor 3
It has a motor torque value calculation means 27 for calculating a motor torque Ti to be obtained by multiplying.

The position detector 4A is a communication means 42 for performing serial communication with the servo amplifier 2A, and a motor rotation position detection for counting up the pulse P generated by the motor rotation pulse generator in accordance with the rotation of the servomotor 3. Means 43, motor rotation speed calculation means 44 for calculating the motor movement amount of the servo motor 3, motor movement amount storage memory 45 for storing the motor movement amount obtained by the motor rotation speed calculation means 44, and motor torque value calculation Motor torque storage memory 4 for storing the motor torque Ti from the means 27
6, a motor life time calculation means 47 for calculating the estimated life time L of the servo motor 3, a motor life time storage memory 48 for holding the estimated life time L, and a motor life time update means 49 for updating the estimated life time L. doing.

FIG. 2 is a state diagram showing an operation pattern of the servomotor 3, and FIG. 3 is an estimated life L in this embodiment.
It is a flowchart for obtaining. In the present embodiment, FIG.
Servo motor 3 in the state of the operation pattern shown in
A case of obtaining the estimated life L of will be described.

The estimated service life L of the servomotor 3 is calculated based on the drive time information and the load information. The average input rotation speed NE (the rotation speed of the motor shaft), the average execution torque TE (the load of the motor shaft), and the motor of the servomotor 3 It is estimated by the rated torque TR, the motor rated rotation speed NR of the servo motor 3, and the expected life LH when the servo motor 3 is used at the rated torque TR and the rated rotation speed NR.

The average input rotation speed NE is a processing cycle ti (unit time) based on a command calculated by the motor rotation speed calculation means 44 in the position detector 4A and a processing obtained from the rotation speed ni in the processing cycle ti. From the motor movement amount per cycle (ti · ni) and the time of one cycle (Σti), it is obtained as Formula 1.
Then it becomes the area of the trapezoid.

[0027]

(Equation 1)

The average execution torque TE is obtained by the equation 2 by the motor movement amount (ti.ni) per processing cycle ti and the motor torque Ti in the processing cycle ti in which the same command to the servo motor 3 is input.

[0029]

(Equation 2)

Based on the result of obtaining the actual life by operating the motor under various loads, the estimated life L is
The average input rotational speed NE, the average execution torque TE of the equation 2, the motor rated torque TR, the motor rated rotational speed NR, and the expected life LH that is a measured value can be obtained by the following equation 3.

[0031]

(Equation 3)

Next, the operation of the servo amplifier 2A and the position detector 4A will be described with reference to FIG. Step S1
When the operation pattern for controlling the servo motor 3 is determined, the position detector 4A activates the life calculation of the servo motor 3 while the life calculation request signal is input from the input unit attached to the positioning device 1. When the life calculation start signal is turned ON and the life calculation start signal is detected to be ON, the process proceeds to step S2, and the life calculation start signal is
The life calculation start signal memo at the time of N is discriminated.

If the life calculation start signal memo is ON, the estimated life L is being calculated, so step S5
However, the life calculation start signal memo is turned off.
In such a state, the estimated life L is calculated from now on, so the process proceeds to step S3, and the motor that is the address of the memory for storing the motor movement amount in the motor movement amount storage memory 45 required for the calculation of the estimated life L The movement amount memory pointer and the motor torque pointer in the motor torque storage memory 46, which is the address of the memory for storing the motor torque, are initialized, the life calculation start signal rises, and the movement amount and torque of the motor are stored in the memory. After the buffer count number i, which means the number of existing
4, the life calculation start signal memo is turned on, and the process proceeds to step S5. That is, when the first estimated life L is calculated, steps S3 and S4 are always performed.

In step S5, the position detector 4A
The rotational position A counted by the motor rotational position detection means 43 for the pulse P generated by the rotation of the servo motor 3 generated from the internal motor rotation pulse generator, and the rotational position B in the previous processing cycle by the motor rotational speed calculation means 44. And the actual rotation speed of the servo motor 3 (ni in FIG. 2) is calculated, and the motor movement amount (ti · ni in FIG. 2 is represented by the area) based on the rotation speed of the servo motor 3. ) Is calculated, the motor movement amount is set in the motor movement amount storage memory 45, and the process proceeds to step S6.

In step S6, the motor torque (Ti in FIG. 2) of the servo motor 3 is communicated with the communication means 21a, 42.
Via the motor torque value calculating means 2 of the servo amplifier 2A
7, the value is set in the motor torque storage memory 46, and the process proceeds to step S7.

In step S7, the motor movement amount memory pointer and the motor torque memory pointer are updated based on the motor movement amount obtained in step S5 and the motor torque obtained in step S6.
Update the buffer count number i. After that, other processing of the position detector 4A is executed.

If the life calculation start signal is OFF in step S1, the process proceeds to step S8, and the state of the life calculation start signal memo is determined. When the life calculation start signal memo is in the ON state, the process proceeds to step S9, and the motor life time calculation means 47 averages based on the motor movement amount, the motor torque, and the buffer count number i for obtaining the estimated life L. After calculating the input rotational speed NE (see Formula 1) and the average execution torque TR (see Formula 2), the estimated life L (see Formula 3) is obtained, and the estimated life L is stored in the motor lifetime storage memory 48. Then, the process proceeds to step S10 to turn off the life calculation start signal memo. If the life calculation start signal is ON in step S1,
Since the motor movement amount, the motor torque, and the buffer count number i for obtaining the estimated life L are not held and the estimated life L cannot be calculated, the process moves to the calculation of the estimated life L for the next shift.

After the estimated life L is calculated, the value of the estimated life L stored in the motor life time storage memory 48 is updated (subtracted) while the motor life time updating means 49 is operating the servo motor 3. ), And when it becomes 0, the communication means 21a and 42 between the servo amplifier 2A and the position detector 4A and the communication means 1 between the positioning device 1 and the servo amplifier 2A.
A warning signal is output to the positioning device 1 via 1, 21. In the positioning device 1, when this warning signal is input,
A warning is issued to notify that the estimated life L of the servomotor has reached 0.

As described above, in the first embodiment, when the estimated life L of the servo motor 3 is detected, the servo motor 3
Since the estimated life L is estimated in consideration of not only the power-on time to the servo motor 3 but also the load on the servo motor 3, the estimated life L of the servo motor 3 can be estimated more accurately.
Further, when the servo motor 3 reaches the estimated life, the position detector 4A or the positioning device 1 automatically issues a warning by voice, light, etc., and troubles due to the motor life of the servo motor 3 can be prevented.

Embodiment 2. FIG. 4 is a block diagram showing another embodiment of the positioning device and the position detector according to the present invention. In the figure, 1 is a positioning device configured the same as in the first embodiment described above, 2A is a servo amplifier,
Reference numeral 3 is a servo motor, and 4B is a position detector. The position detector 4B stores the rotational position of the servo motor 3 detected by the motor rotational position detecting means 43 in the position detector 4A shown in the first embodiment. Motor rotation position storage memory 5
0 is added. The other configurations are similar to those of the above-described conventional example and the first embodiment, and therefore description thereof is omitted.

In the present embodiment, as described in the prior art, the driving condition of the servo motor 3 (servo motor 3
The rotation position of the servo motor 3 stored in the motor rotation position storage memory 50 is calculated inside the position detector 4B without being transmitted from the position detector 4 to the positioning device 1 each time using the communication means 21 and 11. The drive status (rotational position of the servomotor 3 detected by the position detector 4B) is transmitted from the position detector 4B to the positioning device 1A at once in accordance with the communication cycle of serial transmission as required.

FIG. 5 is a flow chart showing the operation of the position detector 4B and the positioning device 1 configured as in this embodiment, and the drive status of the servo motor 3 is shown using the flow chart shown in FIG. The operation at the time of detection will be described. In the normal position detection state, similarly to the above-described detection of the motor rotation position, the motor rotation position detection means 43 gives a count value obtained by counting the pulses P generated by the motor rotation pulse generator, and is instructed by the servo amplifier 2. The rotational position of the servo amplifier 3 is detected in the internal cycle of the position detector 4B based on the speed F, the tamari pulse PC and the like. Similarly, the motor rotation speed calculation means 44 calculates the difference between the rotation position A counted up by the pulse P in the motor rotation position detection means 43 and the rotation position B in the previous processing cycle, and the servo motor 3 Seeking the actual rotation speed of. The rotational position and the rotational speed are output to the positioning device 1 via the communication means 42, 21a and 21, 11.

However, in step S11,
Communication means 11, 21 and 21a, 4 from the positioning device 1
When a continuous detection start request is issued (requested) to the position detector 4B from an arbitrary point via 2, the data in the motor rotation position storage memory 50 of the position detector 4B is all cleared to zero in step 12, and the step S13 and step S1
As 4, the rotational position of the servo motor 3 detected by the motor rotational position detecting means 43 is written in the motor rotational position storage memory 50 so as not to destroy all the data after zero clear (the rotational position of the servo motor 3).

Thereafter, in step S15, it is confirmed whether or not a continuous detection end request is issued (requested) from the positioning device 1 to the position detector 4B via the communication means 11, 21 and 21a, 42, and issuance is performed. If not, the process returns to step S13. If issued, step S16
All the data indicating the rotational position of the servo motor 3 written in the motor rotational position storage memory 50 by the communication means 4 is transmitted.
It is output to the positioning device 1 via 2, 21a and 21, 11.

According to this embodiment, the position detector 4B has a C
Servo motor 3 with a printed circuit board equipped with PU
It is not necessary to detect the motor rotation position of the servo motor 3 by the positioning device 1 because the motor rotation position of the position detector 1 can be detected, the load of the positioning device 1 is reduced, and the position detector 4B detects the position in a fine cycle. The data of the motor rotation position is stored in the motor rotation position storage memory 50, and the data is collectively stored in response to a request from the positioning device 1 via the servo amplifier 2A.
It is possible to detect the motor rotation position of the servo motor 3 in more detail. Further, in the positioning device 1, the data of the rotational position can be transferred to a personal computer or the like to display a waveform of a machine position monitor or the like like a memory type high coder, and the movement of the machine can be diagnosed with high resolution. . Further, in the present embodiment, the configuration in which the motor rotation position of the servo motor 3 is transmitted from the position detector 4B to the positioning device 1 at a time has been described, but the present invention is not limited to this, and the latest accurate servo motor is always used. In order to detect the motor rotation position of the servo motor 3, the motor rotation position of the servo motor 3 may be transmitted from the position detector 4B to the positioning device 1 every time it is detected.

Embodiment 3 FIG. FIG. 6 is a block diagram showing an embodiment of the positioning device and the position detector according to the present invention. In the figure, reference numeral 51 is a position calculation means at the time of sensor input for detecting the motor rotation position of the servomotor 3 based on the sensor detection signal from the sensor signal detection means 52 when a sensor input signal is input from the external sensor 5. The other configurations are similar to those of the above-described embodiment, and thus the description thereof will be omitted.

In this embodiment, as shown in the above-described embodiments, a means for detecting the motor rotation position of the servomotor 3 is provided inside the position detector 4C, and the external sensor 5 is detected by the sensor signal detecting means 52. The sensor input signal from the external sensor 5 is directly input to the position detector 4C, and the time lag for detecting the rotational position of the servo motor 3 at the moment of input is reduced.

Next, the operation of this embodiment will be described.
First, when the sensor input signal is input from the external sensor 5 to the sensor signal detection means 52 of the position detector 4C, the sensor signal detection means 52 outputs the sensor detection signal to the position calculation means 51 at the time of sensor input. The position calculation means 51 at the time of sensor input which receives the sensor detection signal detects the motor rotation position of the servo motor 3 based on the count value from the motor rotation position detection means 43 as in the above-described embodiment. The detected motor rotation position is set in the position calculation means at the time of sensor input, and the set motor rotation position is output to the positioning device 1 via the communication means 42, 21a and 21, 11.

According to this embodiment, it is possible to accurately detect the motor rotation position of the servo motor 3 at the moment when the sensor input signal is input from the external sensor 5.

Embodiment 4. FIG. 7 is a block diagram showing an embodiment of the positioning device and the position detector according to the present invention. In the figure, 53a is a motor allowable rotation speed storage memory in which the allowable rotation speed of the servo motor 3 is written in advance before shipment, and 54 is an overspeed monitoring means of the servo motor 3. The other configurations are similar to those of the above-described embodiment, and thus the description thereof will be omitted.

In the present embodiment, the position detector 4D is provided with a motor allowable rotation speed storage memory 53a, and the servo motor 3 and the position detector 4D are pre-shipped together with the servo motor 3 in the motor allowable rotation speed storage memory 53a. The allowable rotation speed defined in the above is written, the position detector 4D itself calculates the motor rotation speed of the servo motor 3 from the motor rotation position, and monitors whether the allowable rotation speed is exceeded. .

FIG. 8 is a flow chart showing the operation of the position detector 4D and the positioning device 1 configured as in this embodiment. The motor rotation speed of the servo motor 3 will be described with reference to the flow chart shown in FIG. The operation for monitoring whether the rotation speed exceeds the allowable rotation speed will be described. Normally, the servo motor 3 and the position detector 4D are shipped as an integrated product. Therefore, one position detector 4D is never connected to a plurality of types of servo motors 3. Therefore, before shipment, the allowable rotation speed of the servo motor 3 is set to the motor rotation speed storage memory 53 of the position detector 4D.
Write in a.

When the user drives the servomotor 3, in step S17, the motor rotation speed calculation means 44 is used.
Calculates the difference between the rotational position A counted by the motor rotational position detection means 43 with the pulse P and the rotational position B in the previous processing cycle, and obtains the actual rotational speed of the servo motor 3. Then, in step S18, the overspeed monitoring means 54 monitors whether or not the current motor rotation speed exceeds the allowable rotation speed previously written in the motor allowable rotation speed storage memory 53a. If the allowable rotation speed is not exceeded, the process returns to step S17, and if the allowable rotation speed is exceeded, the process proceeds to step S19 to issue a motor overspeed warning to the positioning device via the communication means 42, 21a and 21, 11. Output.

According to this embodiment, the motor allowable rotation speed storage memory 53a is provided inside the position detector 4D that is shipped together with the servo motor 3, and the predetermined allowable rotation speed of the servo motor 3 is detected by the position detector. Since 4D is set at the time of shipment, it is not necessary for the user to set the allowable rotation speed of the servo motor 3 in the servo amplifier 2A while looking at the manual after delivery to the user. You don't have to worry about setting and save time. Further, when the permissible rotation speed is exceeded, a speed warning is output from the motor, and the positioning device 1 receiving the warning can issue a warning by sound, light, etc., and workability is improved.

Embodiment 5 FIG. FIG. 9 is a block diagram showing an embodiment of the positioning device and the position detector according to the present invention. In the figure, 55 is a counter value from the motor rotation position detecting means 43 based on the position correction amount Lo with respect to the correction reference length (10000 pulses) input from the external device via the servo amplifier 2A or the external I / F. Is a motor rotational position correcting means, which is a correction means for correcting the output signal, 56 is an external signal input means for connecting the external input device 6, and 57 is an external signal output means for connecting to the external output device 7. The other configurations are similar to those of the above-described embodiment, and thus the description thereof will be omitted.

In the present embodiment, in the mechanism in which the servomotor 3 is attached and which expands and contracts depending on the load, temperature, etc.,
The rotation position of the servo motor 3 based on the counter value counted by the motor rotation pulse generator and the actual rotation position where an error occurs due to expansion and contraction are corrected. The feedback cumulative counter (FBP0) for detecting the actual rotational position of the servo motor 3 corrected by the motor rotational position correction calculation means 55 is a position correction reference length (100).
00 pulse), the position correction amount Lo (pulse) and the feedback correction amount (FBP1), which is the counter value from the motor rotation position detecting means 43, can be obtained by the following equation.

[0057]

(Equation 4)

A pulse P generated by the rotation of the servo motor 3 which is corrected based on the feedback correction amount shown in the equation (4).
Is a motor rotation position detecting means 43 inside the position detector 4E.
, And count the pulses P transmitted there. The motor rotation position is calculated from the count value counted by the motor rotation position detection means 43 as in the second embodiment, and is transmitted to the servo amplifier 2A as necessary. As a result, it is possible to perform feedback correction corresponding to expansion and contraction of the mechanical system due to load, temperature, etc., and it is possible to accurately detect the motor rotation position of the servo motor 3.

In practice, for example, when performing vertical position control in an automated warehouse, if the machine stretches due to load, temperature, etc., the correction amount with respect to the position correction reference length will be minus (100).
If the machine contracts due to load, temperature, etc., add the correction amount to the position correction reference length (10000).
With the above, it is possible to position at a predetermined position.

Further, the position detector 4E is provided with an external signal input means 56 and an external signal output means 57 for exchanging signals with an external input / output device, and an external limit switch or the like installed around the servo motor 3 is provided. The signal input from the input device 6 is input to the external signal input means 56, where the input data (state of the input signal) is read and then transferred to the servo amplifier 2A via the communication means 42, 21a. Meanwhile, the communication means 21a, 42 from the servo amplifier 2A
The output data is transferred to the position detector 4E via, and after the output data is read, a signal is output from the external signal output means 57 to the external output device 7. Therefore, input / output signals to / from the external input device 6 and the external output device 7 installed around the position detector 4E can be connected to the positioning device 1 via the position detector 4E, and the external input device 6 and There is no need to wire from the external output device 7 to the positioning device 1, and signals can be sent and received by wiring to the nearest position detector 4E, and wiring can be saved.

[0061]

Since the present invention is configured as described above, it has the following effects. Drive time detecting means for detecting a drive time of a motor driven based on a command, load detecting means for detecting a load applied to the motor, load information from the load detecting means and drive time information from the drive time detecting means Estimated life calculation means for calculating the estimated life of the motor based on the above, and it is possible to accurately calculate the estimated life of the motor based on the energization time and the load applied to the motor, and workability such as maintenance of the motor is improved. improves.

Further, pulse generating means for oscillating a pulse according to the driving of the motor driven based on the command output from the command device through the communication line, the counting result of the pulse oscillated from the pulse generating means, and the above command. Based on the above, a rotational position detecting means for calculating the rotational position of the motor is provided, and the rotational position of the motor calculated by the rotational position detecting means is transmitted to the command device. Instead of transmitting the data for calculation to the command device and calculating the rotational position of the motor by the command device, the rotational position of the motor is calculated inside the position detector, and the calculated rotational position of the motor is commanded by the command device. Therefore, the detection accuracy of the rotational position of the motor is improved.

Further, since the memory means for holding a plurality of rotational positions of the motor calculated by the rotational position detecting means is held, the calculated rotational position of the motor is transmitted to the command device side through the communication means. Even during this period, it becomes possible to calculate a new motor rotational position at the detection cycle inside the position detector and hold multiple points in the memory means one after another. The rotational position of the motor can be transmitted to the positioning device one after another, and detailed control of the motor can be performed by the detailed data of the rotational position of the motor.

Further, a sensor signal detecting means to which an external sensor is connected is provided, and when the sensor signal detecting means detects a sensor input signal from the external sensor, the rotational position detecting means calculates the rotational position of the motor. I did so,
The time lag from the input of the sensor input signal to the calculation of the rotational position is shorter than before, and the rotational position of the motor at the moment when the sensor input signal is detected can be detected.

Further, based on the allowable rotation speed storage memory for storing in advance the allowable rotation speed determined for each motor, and the change amount of the rotation position of the motor detected by the rotation position detecting means, the rotation speed of the motor is determined. Based on the rotation speed calculation means for calculating, the rotation speed of the motor calculated by the rotation speed calculation means and the allowable rotation speed stored in the allowable rotation speed storage memory, the rotation speed of the motor is the allowable rotation speed. Since it is provided with a monitoring means for monitoring the motor so as not to exceed the above, it becomes possible to store the allowable rotation speed of the motor in advance in the position detector that is normally shipped together with the motor. When the user uses the motor, it is not necessary to newly set the allowable rotation speed while referring to the manual etc. On there is no labor of work at the time of its settings can be saved.

Further, since the correction means is provided for correcting the pulse oscillated by the pulse generating means in accordance with the driving of the motor based on the external condition due to the temperature or the load of the motor, the pulse generating means by the expansion and contraction of the mechanical system due to the temperature or the load. It becomes possible to correct the error of the pulse from, and it becomes possible to detect the accurate rotational position of the motor.

[Brief description of the drawings]

FIG. 1 is a block diagram of a positioning device and a position detector according to an embodiment of the present invention.

FIG. 2 is a form of an operation pattern of a machine according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating operations of the positioning device and the position detector according to the embodiment of the present invention.

FIG. 4 is a block diagram of a positioning device and a position detector according to an embodiment of the present invention.

FIG. 5 is a flow chart illustrating operations of the positioning device and the position detector according to the embodiment of the present invention.

FIG. 6 is a block diagram of a positioning device and a position detector according to an embodiment of the present invention.

FIG. 7 is a block diagram of a positioning device and a position detector according to an embodiment of the present invention.

FIG. 8 is a flow chart illustrating operations of the positioning device and the position detector according to the embodiment of the present invention.

FIG. 9 is a block diagram of a positioning device and a position detector according to an embodiment of the present invention.

FIG. 10 is a block diagram of a positioning device and a position detector according to an embodiment of the conventional invention.

[Explanation of symbols]

3 Servo motors 4A, 4B, 4C, 4D,
4E Position detector 5 External memory 43 Motor rotation position detection means 44 Motor rotation speed calculation means 47 Motor life time calculation means 50 Motor rotation position storage memory 53a Motor allowable rotation speed storage memory 54 Overspeed monitoring means 55 Motor rotation position correction means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshichi Takizawa Inventor Marunouchi 2-3-3, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Akira Shima 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd.

Claims (6)

[Claims] 1. A drive time detecting means for detecting a drive time of a motor driven based on a command, a load detecting means for detecting a load applied to the motor, load information from the load detecting means and the drive time detecting means. And an estimated life calculation means for calculating an estimated life of the motor based on driving time information from the position detector. 2. A pulse generating means for oscillating a pulse according to the driving of a motor driven based on a command output from a command device via a communication line, a counting result of the pulse oscillated from the pulse generating means and the command. A rotational position detecting means for calculating the rotational position of the motor based on the above, and transmitting the rotational position of the motor calculated by the rotational position detecting means to the command device. . 3. The position detector according to claim 2, further comprising memory means for holding a plurality of rotational positions of the motor calculated by the rotational position detecting means. 4. A sensor signal detecting means to which an external sensor is connected, and when the sensor signal detecting means detects a sensor input signal from the external sensor, the rotational position detecting means calculates the rotational position of the motor. The position detector according to claim 2 or 3, wherein: 5. An allowable rotation speed storage memory that stores in advance an allowable rotation speed determined for each motor, and the rotation speed of the motor based on the amount of change in the rotation position of the motor detected by the rotation position detection means. Based on the rotation speed calculation means for calculating, the rotation speed of the motor calculated by the rotation speed calculation means, and the allowable rotation speed stored in the allowable rotation speed storage memory, the rotation speed of the motor is the allowable rotation speed. The position detector according to claim 2, further comprising: a monitoring unit that monitors the motor so as not to exceed the speed. 6. The position detector according to claim 2, further comprising a correction unit that corrects the pulse oscillated by the pulse generation unit according to the driving of the motor based on an external condition due to the temperature or the load of the motor. .