JP7108394B2 - Motor holding brake life determination system, motor holding brake life determination device, and motor holding brake life determination method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for determining the service life of a motor holding brake, and more particularly to a technology for determining the service life of a mechanical brake using a servomotor as a drive source.

The control motor has a built-in holding brake (motor brake) to hold the position when the motor is stopped, and a braking brake (motor brake) to actively brake the rotation of the motor without stopping at the stopped position. (brake for motor) is built in. Also, there has been proposed a technique of using a holding brake for braking when an abnormality occurs in the control device.

For these motors, for example, a disc fixed to the motor shaft, a brake pad attached to the surface of the disc, and an armature (contact piece) biased by a spring or the like to contact the brake pad. , and an electromagnetic coil that attracts the armature with an electromagnetic attraction force and pulls it away from the brake pad. When the motor is running, the electromagnetic coil is energized and the armature is kept separated from the brake pads. When applying the brake, the energization to the electromagnetic coil is stopped. As a result, the electromagnetic force disappears, and the armature comes into sliding contact with the brake pad due to the urging force of the spring, and the shaft is braked by the frictional force generated at that time.

By the way, it is extremely important to determine the life of the holding brake. Conventionally, the following life determination techniques are known.
In the technique described in Patent Document 1, the amount of work of the brake is calculated from the rotational angle and angular velocity of the servomotor during braking, and the amount of work is multiplied each time braking is performed, and the total amount of work of the brake is calculated. Determine lifespan. Alternatively, the total amount of work of the brake is stored, the amount of work during braking is calculated, and the amount of work is subtracted from the total amount of work of the brake to judge the service life.
Further, in the technique described in Patent Document 2, a table of possible braking times for judging the life of the brake, the total work amount, and accumulated data during braking are stored in a control device (amplifier).

JP 2006-155199 A Japanese Patent Application Laid-Open No. 2003-130096

With the techniques described in Patent Documents 1 and 2, test measurements must be performed in order to create a table of possible braking times for each brake (motor). In addition, there is a problem that life diagnosis requires complicated calculations and reference to data tables.
In addition, it is necessary to store a large amount of data in the CPU on the control device side, and it is necessary to erase or preset each data when adding or changing data due to the addition of a new motor, or when changing or replacing the combination of motor and amplifier. There is a problem that there is a possibility that accurate life span diagnosis cannot be performed.

An object of the present invention is to accurately and simply diagnose the life of a holding brake. Another object of the present invention is to accurately diagnose the life of a holding brake even if the motor and motor control device are replaced or replaced.

According to one aspect of the present invention, there is provided a life determination system for a holding brake of a motor, which is provided on a shaft of a motor and controlled by a motor control device to brake or hold the shaft by frictional force, wherein the system is provided in an encoder of the motor. and an encoder storage unit for storing parameters relating to the life of the holding brake and calculation results based thereon.
The parameters include the presence or absence of the holding brake, the allowable amount of rotation that defines the life of the holding brake, and the amount of rotation of the shaft during operation of the holding brake, that is, in a state where the holding brake holds the motor shaft. and a cumulative amount of rotation.
By storing the cumulative rotation amount on the encoder side, the accuracy of life diagnosis can be maintained even when the motor and the motor control device are replaced or replaced.

It is preferable that the motor control device includes a life diagnosis section that reads and acquires the parameters in the encoder storage section and estimates a life based on the allowable rotation amount and the accumulated rotation amount.
It is preferable to continuously update the cumulative amount of rotation stored in the encoder storage unit.

The present invention provides a motor holding brake life determination device in a motor holding brake life determination system for braking or holding the shaft by a frictional force controlled by a motor control device, the device comprising: and a life diagnosis unit that acquires the allowable rotation amount and the cumulative rotation amount from an encoder storage unit that is provided in the encoder and stores parameters related to the life of the holding brake and the calculation result based on the parameters, and diagnoses the life. This is a motor holding brake life determination device.

According to another aspect of the present invention, there is provided a motor holding brake life judgment method in a life judgment system for a motor holding brake that brakes or holds the shaft by means of frictional force controlled by a motor control device. and a life diagnosis step for diagnosing the life by acquiring the allowable rotation amount and the cumulative rotation amount from an encoder storage unit provided in the encoder of the motor and storing parameters relating to the life of the holding brake and calculation results based thereon. A motor holding brake life determination method is provided.

ADVANTAGE OF THE INVENTION According to this invention, brake life can be diagnosed simply and accurately.
Further, according to the present invention, even if the motor and the motor control device are replaced or exchanged, the brake life can be diagnosed with high accuracy.

1 is a functional block diagram showing a configuration example of a motor holding brake life determination system according to an embodiment of the present invention; FIG. It is a flowchart figure which shows the flow of preparation processing. It is a flowchart figure which shows the flow of the initialization process of a motor control apparatus. FIG. 10 is a flow chart showing the flow of remaining life calculation and display processing. It is a figure which shows an example of the data storage procedure by this Embodiment.

In this specification, the life of the holding brake is determined from the amount of wear of the friction plates of the holding brake. The amount of wear of the holding brake can be determined from the total amount of rotation when the shaft rotates while the holding brake holds the motor shaft.
Therefore, the timing at which this total amount of rotation (hereinafter referred to as "permissible amount of rotation") is reached is defined as the life of the holding brake.
Since the allowable rotation amount varies depending on the specifications of the holding brake, it is calculated in advance for each holding brake attached to the motor.

The holding brake life determination process is performed according to the following procedure.
1) The amount of rotation of the motor shaft is accumulated while the holding brake is holding the motor shaft.
2) Remaining period until life (remaining life = allowable rotation amount - accumulated rotation amount)

Retention of information:
The parameters and calculation results related to the holding brake life are saved in the encoder's built-in non-volatile memory. The stored data are, for example, "presence/absence of holding brake", "permissible amount of rotation", "accumulated amount of rotation", and the like.

Conditions for the motor shaft to rotate while the holding brake is holding the motor shaft are cases where the following conditions 1) to 3) are satisfied.
1) When an abnormality occurs while the motor is rotating and the motor must be stopped 2) When the shaft is forced to rotate by an external force while the servo motor is not energized 3) When the servo motor is excited If the motor rotates between the time the holding brake releases the shaft

Hereinafter, a motor holding brake life determination technique according to an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a functional block diagram showing one configuration example of a motor holding brake life determination system according to the present embodiment. As shown in FIG. 1, a motor holding brake life determination system A according to the present embodiment includes a motor control device 1 and a servomotor 21 with a holding brake. The motor control device 1 is connected to a holding brake control circuit 3 which receives a holding brake control signal SG1 for controlling the holding brake and controls the holding brake operation.

The holding brake-equipped servomotor 21 has a motor M, a holding brake B for the motor M, and an encoder 23 . The encoder 23 has an encoder-side storage unit 23-1, a reply data generation unit 23-2, a communication unit 23-3, a request command analysis unit 23-4, and a position data calculation unit 23-5. is doing. The storage unit 23-1 on the encoder side stores the presence/absence of a holding brake D13, the allowable amount of rotation D14, and the cumulative amount of rotation D15.
The motor control device 1 includes a holding brake control unit 1-1, an encoder communication unit 1-2, a reply data analysis unit 1-3, a holding brake state determination unit 1-4, and a holding brake rotation amount calculation unit 1-. 5, holding brake rotation amount accumulation unit 1-6, life diagnosis unit 1-7, life display unit 1-8, and request command generation unit 1-9.
The holding brake life determination process according to the present embodiment will be described in detail below with reference to the flow charts of FIGS. 2 to 5. FIG. Description will be made with reference to each functional block in FIG.

FIG. 2 is a flowchart showing the flow of preparation processing. As shown in FIG. 2, the preparatory process is started (start), and in step S1, the "permissible rotation amount" for each holding brake B is calculated. In step S2, the external setting unit 11 sets information on "presence/absence of a holding brake" in the storage unit 23-1 inside the encoder. In step S3, the external setting unit 11 sets the information of the "permissible amount of rotation" in the storage unit 23-1 inside the encoder. In step S4, the cumulative rotation amount information D15 in the storage section 23-1 inside the encoder is cleared.
This completes the preparation process. That is, the holding brake presence/absence information D13 and the allowable rotation amount information D14 are stored in the storage unit 23-1 on the encoder side.

FIG. 3 is a flow chart showing the flow of initialization processing of the motor control device 1. As shown in FIG. Initialization processing starts (start), and in step S11, holding brake presence/absence information D13 is acquired from the storage unit 23-1 inside the encoder. This is stored in the memory 1-8a of the life display unit 1-8 via the unit 1-2 and the reply data analysis unit 1-3.
Next, in step S12, the permissible rotation amount information D14 is acquired from the storage section 23-1 inside the encoder and stored in the memory 1-7a of the life diagnosis section 1-7. Further, in step S13, if the cumulative rotation amount information D15 is stored in the storage unit 23-1 inside the encoder, the cumulative rotation amount information D15 is acquired, and stored in the memory 1-7a of the life diagnosis unit 1-7. memorize to
With the above processing, the initialization processing of the motor control device 1 is completed.
The reply data generator 23-2 selects the reply data D21 according to the reply data selection signal SG12 from the request command analyzer 23-4.

A brief description will be given of the processing after initialization.
After the initialization process, the position data D16 becomes the reply data D21. Then, the process proceeds to the process of the flowchart of FIG. 4, which will be described later, and the output of the holding brake control signal SG1 from the holding brake control section 1-1 is monitored.

FIG. 4 is a flow chart showing the flow of remaining life calculation and display processing.
When the process starts (start), first, in step S21, the holding brake state determination unit 1-4 monitors the holding brake control signal SG1 from the holding brake control unit 1-1, and the holding brake control signal SG1 is In the case of the operating state (Yes), the cumulative rotation amount calculation process Sa is performed.
If No, the process proceeds to step Sc, which will be described later.
The cumulative rotation amount calculation processing step Sa includes the following processing.

(Step Sa)
1) In step S22, the position data D1 obtained based on the position data D16 calculated by the position data calculator 23-5 is used to hold the position data when the holding brake control signal SG1 changes to the operation start state.
2) In step S23, the holding brake rotation amount calculator 1-5 obtains the "rotation amount during holding brake operation" from the position held at the start of the holding brake operation.
3) In step S24, the holding brake rotation amount accumulator 1-6 adds the "accumulated rotation amount during holding brake operation" D3 to the previous "accumulated rotation amount" D2 from the reply data analysis unit 1-3. to calculate the cumulative amount of rotation and store it in the memory 1-6a.
Note that "during the holding brake operation" means a state in which the holding brake B holds the motor shaft.

(Step Sb)
Then, proceed to step Sb. Step Sb carries out processing for calculating the remaining life.
In this process, the life diagnosis unit 1-7 calculates the remaining life in step S25. That is, as shown in step S25, the life diagnosis unit 1-7 subtracts the "accumulated rotation amount" D3 from the "allowable rotation amount" D4 from the reply data analysis unit 1-3 to calculate the "remaining life" D5. do. This is held in the memory 1-7a.
In the case of No in step S21, and following step S25, in step Sc, for example, remaining life display processing is performed.

(Step Sc)
First, in step S26, when the life display unit 1-8 receives the remaining life D5 and receives the holding brake presence signal of the holding brake presence/absence signal SG2 from the return data analysis unit 1-3 (Yes), the process proceeds to step S27. The life display section 1-8 displays the remaining life D5. Data for display may be stored in the memory 1-8a.
In step S26, even if the life display unit 1-8 receives the remaining life D5, if it receives the no holding brake signal of the holding brake presence/absence signal SG2 from the return data analysis unit 1-3 (No), the process proceeds to step S28. The life display section 1-8 does not display the remaining life D5.
With the above, the life determination/display processing is terminated (END).

FIG. 5 is a diagram showing an example of a data storage procedure according to this embodiment.
As shown in FIG. 5, when the process is started (start), in step S31, the holding brake rotation amount accumulator 1-6 determines whether or not the cumulative rotation amount D3 has changed (step S31), If Yes, the process proceeds to step Sd for updating the storage of the accumulated amount of rotation Sd, and if No, the process ends (end).
The storage update processing Sd of the accumulated rotation amount is performed in the following procedure.
(Step Sd)
First, in step S32, the holding brake rotation amount accumulator 1-6 outputs a new "accumulated rotation amount" D3 to the request command generator 1-9.
In step S33, the request command generator 1-9 generates a write request command C1 to the encoder and notifies it to the encoder communication unit 1-2. The request command C1 is output when the cumulative amount of rotation changes.
In step S34, the encoder communication unit 1-2 transmits the "accumulated amount of rotation" D12 to the encoder and stores it in the storage unit 23-1 inside the encoder.
Thus, the process of storing the accumulated rotation amount in the encoder ends (end).

As described above, according to the present embodiment, the storage unit 23-1 provided in the encoder 23 on the side of the servo motor controlled by the motor control device stores "presence/absence of the holding brake" and "life value of the holding brake". The information is held in advance, and the "accumulated amount of rotation of the holding brake up to the present time" is saved.
By storing the cumulative rotation amount on the encoder side, the accuracy of life diagnosis can be maintained even when the motor and the motor control device are replaced or replaced.
That is, even if the motor is changed, there is no need to change the holding brake life value of the motor controller. Also, even if the motor control device is replaced, the remaining life can be inherited and correctly estimated.

In this embodiment, the life of the holding brake is calculated and specified in advance from the allowable rotation amount. Next, the holding brake monitors the amount of rotation of the motor while holding the motor shaft, accumulates the amount of rotation of the motor, and compares it with the allowable amount of rotation. It is possible to diagnose the service life of the brake.
By storing the allowable rotation amount, the cumulative amount of rotation when the holding brake holds the motor shaft, and the presence or absence of the holding brake in the memory holding means of the motor encoder, it becomes unnecessary to store a large amount of data in the motor control device side. . In addition, it is possible to eliminate problems such as troublesome work due to changing the combination or replacement of the motor and the motor control device, misdiagnosis of the service life, and erroneous display.

(summary)
This embodiment has the following advantages.
1) The life can be easily estimated by comparing the allowable amount of rotation of the holding brake and the accumulated amount of rotation of the holding brake while holding the motor shaft, without requiring complicated calculations.
2) Storing the "permissible amount of rotation" (holding brake life) in the non-volatile memory built into the encoder has the following advantages.

2-1) There are a wide variety of holding brakes attached to servo motors due to differences in size, holding force, etc., and the service life values are also different. In the method of storing the "permissible amount of rotation" in the motor control device, each time the holding brake is changed, the "permissible amount of rotation" is stored in the motor control device.
Therefore, if it is stored in the non-volatile memory incorporated in the encoder, a change in the storage of the "permissible rotation amount" in the motor control device occurs each time the holding brake is changed. change is unnecessary.
2-2) Even in mass-produced motors, the specifications of the holding brake may be changed in the middle. In that case, the "permissible amount of rotation" will be different before and after the change of the holding brake, so it is necessary to change the "permissible amount of rotation" set in the motor control device. Furthermore, if the holding brake before the specification change is connected to the motor control device after the "allowable rotation amount" is changed (or vice versa), the life cannot be calculated correctly.
Therefore, if it is stored in the non-volatile memory built into the encoder, the remaining life can always be calculated correctly regardless of which one is replaced.
3) Storing the "accumulated amount of rotation" in the non-volatile memory built into the encoder has the following advantages.

3-1) If the "accumulated amount of rotation" is stored in the motor control device, the "accumulated amount of rotation" of the motor control device after replacement is 0 when the motor control device is replaced. Device value must be set.
Therefore, if stored in a non-volatile memory built in the encoder, the remaining life can be correctly calculated regardless of the connection with any motor control device.
3-2) Similarly, even when the combination of the servomotor and the motor control device is exchanged, the remaining life can be calculated correctly.
4) Since the "presence/absence of holding brake" information is stored in the encoder memory, the user does not need to set the presence/absence of the holding brake to the motor control device, and the motor control device can automatically judge. .

In the above-described embodiments, the illustrated configurations and the like are not limited to these, and can be changed as appropriate within the scope of exhibiting the effects of the present invention. In addition, it is possible to carry out by appropriately modifying the present invention as long as it does not deviate from the scope of the purpose of the present invention.
In addition, each component of the present invention can be selected arbitrarily, and the present invention includes an invention having a selected configuration.

INDUSTRIAL APPLICABILITY The present invention can be used for a motor holding brake life diagnosis device.

A... Motor holding brake life determination system B... Holding brake M... Motor 1... Motor control device 1-1... Holding brake control unit 1-2... Encoder communication unit 1-3... Return data analysis unit 1-4... Holding brake State judgment unit 1-5: Holding brake rotation amount calculation unit 1-6: Holding brake rotation amount accumulation unit 1-7: Life diagnosis unit 1-8: Life display unit 1-9: Request command generation unit 3: Holding brake control Circuit 21 Servo motor with holding brake 23 Encoder 23-1 Storage unit 23-2 Reply data generation unit 23-3 Communication unit 23-4 Request command analysis unit 23-5 Position data calculation unit

Claims (4)

A life determination system for a holding brake of a motor that is provided on a shaft of a motor and controlled by a motor control device to brake or hold the shaft by frictional force,
A parameter relating to the life of the holding brake provided in the encoder of the motor and a calculation result based thereon are stored.The parameters are the presence or absence of the holding brake, the allowable amount of rotation that defines the life of the holding brake, and the cumulative amount of rotation that is the accumulation of the amount of rotation of the shaft when the holding brake holds the motor shaft. and includingEncoder memory When,
a life diagnosing unit provided on the motor control device side, reading and acquiring the parameters in the encoder storage unit, and estimating the life based on the allowable rotation amount and the cumulative rotation amount. ,
A life determination system for a holding brake of a motor characterized by: 2. The life determination system for a motor holding brake according to claim 1 , wherein said cumulative rotation amount stored in said encoder storage unit is continuously updated. A motor holding brake life determination device in a life determination system for a motor holding brake provided on a motor shaft and controlled by a motor control device to brake or hold the shaft by frictional force,
a life diagnosing unit for diagnosing a life by acquiring an allowable amount of rotation and an accumulated amount of rotation from an encoder storage unit provided in the encoder of the motor and storing parameters relating to the life of the holding brake and calculation results based thereon;
Said parameters are:
including the presence or absence of the holding brake, an allowable amount of rotation that defines the life of the holding brake, and an accumulated amount of rotation that is the accumulation of the amount of rotation of the shaft while the holding brake holds the motor shaft. A motor holding brake life determination device characterized by: A motor holding brake life determination method in a life determination system for a motor holding brake provided on a motor shaft and controlled by a motor control device to brake or hold the shaft by frictional force, comprising:
a life diagnosing step of diagnosing a life by acquiring an allowable amount of rotation and an accumulated amount of rotation from an encoder storage unit provided in the encoder of the motor and storing parameters relating to the life of the holding brake and calculation results based thereon;
Said parameters are:
including the presence or absence of the holding brake, an allowable amount of rotation that defines the life of the holding brake, and an accumulated amount of rotation that is the accumulation of the amount of rotation of the shaft while the holding brake holds the motor shaft. A holding brake life determination method for a motor characterized by:

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