JP2011062020A - Dc motor management device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute a device for managing the life of a DC motor having a brush. <P>SOLUTION: During operation of the DC motor, the number of revolutions of the DC motor M is acquired by a rotation number acquisition means 25, and current values supplied to the DC motor are acquired by a current value acquisition means 26, at preset intervals. By an abrasion evaluation means 27, a multiplication value X is calculated by multiplying the acquired number of revolutions by a current value, an abrasion evaluation value K is acquired from this multiplication value X, and the acquired evaluation value K is added to calculate an integration value Y. A replacement timing estimation means 28 calculates distance information on which a vehicle can travel, from the integration value Y, an initial life value, and the traveling distance information. This travelable distance information is stored in a memory 31 as notification information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a DC motor management device for managing the life of a DC motor having a brush, and more particularly, in a DC motor having a structure for supplying electric power from a brush to a commutator. The present invention relates to an improvement of a device for managing a DC motor.

  As a DC motor management device configured as described above, Patent Document 1 includes a start-up counter that counts the number of start-ups of a brushed servo motor and an operation time counter that counts operation time. The operation time management mode and the management mode selection unit for selecting the activation frequency management mode mainly including the activation frequency, and a control configuration in which the brush life warning unit and the alarm display unit are connected to the CPU. The configuration is shown.

  In this Patent Document 1, when one of the operation time management mode and the startup number management mode is selected, a brush wear degree value is obtained by calculation, and when this brush wear degree value becomes a set value or less, Processing for warning the life of the brush to the display unit is performed.

  As a DC motor management device, Patent Document 2 discloses a brush wear detection device that includes a current sensor that detects a current supplied to a brush motor that drives a hydraulic pump in a vehicle-mounted hydraulic device, and that detects the end of life of the brush. I have. And it is comprised so that the lifetime end of the brush of a brush motor may be detected by the comparison with the electric current detected with the electric current sensor, and the reference current during the pressure restriction | limiting by a relief valve.

  In Patent Document 2, in the relief state where the relief valve is operated by the hydraulic pump, when the brush motor has reached the end of its life, the current value supplied to the motor is compared with that before the end of the life. By using the phenomenon that the fluctuation range becomes large, it is determined that the brush motor has reached the end of its life and the warning lamp is turned on.

Japanese Patent Laid-Open No. Sho 62-155744 JP 2008-301567 A

  Taking an automobile as an example, a DC motor having a brush is small and inexpensive, and is often provided in a vehicle body because of good response and high starting torque. As is well known, a DC motor having a brush has a limited period of use because the brush wears during operation. For this reason, as described in Patent Document 1 and Patent Document 2, there has been proposed a technique that warns that a brush has reached the end of its life by lighting a warning lamp or the like.

  However, as described in Patent Document 1 and Patent Document 2, when a warning is given that the brush of the DC motor is worn to the limit where it can be used, the DC motor is already properly operated when the warning is issued. There is room for improvement because it is possible that the situation is impossible.

  In order to eliminate such an inconvenience, it may be possible to grasp and notify in advance that the replacement time of the DC motor has been reached due to wear of the brush. However, it is difficult to cope with the detection of the end of life due to wear of the brush as in Patent Document 2. On the other hand, in what is described in Patent Document 1, it can be considered that the end of life can be detected by changing the control mode, whether the control mainly manages the operation time or the control mainly manages the number of activations. . However, the amount of wear of the brush cannot ignore the influence of the rotational speed of the DC motor and the current flowing through the brush, and it is difficult to estimate the life with high accuracy if the load of the DC motor fluctuates. is there.

  An object of the present invention is to rationally configure an apparatus capable of managing the life of a DC motor having a brush.

A feature of the present invention is a DC motor management device that manages the life of a DC motor having a brush,
A rotation speed acquisition means for acquiring the rotation speed (rotation speed) of the DC motor; and a current value acquisition means for acquiring a current value supplied to the DC motor;
Wear evaluation means for obtaining a wear evaluation value from the brush wear characteristics of the DC motor based on a multiplication value obtained by multiplying the rotation speed by the current value, and corresponding to the wear amount of the brush by integrating the wear evaluation value. The point is to output the integrated value.

In a DC motor having a brush, a factor that determines the amount of wear of the brush can be the rotational speed of the DC motor. It is also known that when a load is applied to the DC motor, the value of the current flowing through the brush increases, and the wear of the brush progresses due to a large current flowing at the contact surface between the brush and the commutator. It has been.
As described above, the rotational speed and the current value are considered as factors that determine the amount of wear of the brush, and in the present invention, the wear from the brush wear characteristics of the DC motor based on the multiplication value calculated by multiplying the motor rotational speed by the current value. Get evaluation value. This wear evaluation characteristic corresponds to the amount of wear of the brush. Next, an integrated value obtained by integrating this wear evaluation characteristic can be acquired as the total wear amount of the brush in the integrated period. In this way, even when the rotational speed and current value of the DC motor fluctuate, the wear amount reflected by the rotational speed and current value can be acquired, and a device that can manage the life of the DC motor having a brush is configured. it can.

  The present invention may include a replacement time estimating means for estimating a replacement time based on the integrated value.

  According to this, it is possible to estimate the replacement time of the DC motor from this integrated value. That is, since the replacement time of the DC motor can be known with certainty, an inexpensive brushed DC motor can be used.

  In the present invention, the wear evaluation means multiplies the rotation speed acquired by the rotation speed acquisition means at each set interval by the current value acquired by the current value acquisition means at each set interval. A multiplication module for calculating a value, a wear evaluation module for acquiring the wear evaluation value from a wear characteristic table based on the wear characteristic information based on the multiplication value calculated for each set interval, and the wear evaluation module acquired by the wear evaluation module You may provide the integrating | accumulating module which integrates | wears an abrasion evaluation value.

  According to this, the multiplication module can calculate the multiplication value by multiplying the rotation speed and current value acquired at each set interval, and the wear evaluation module can obtain the wear evaluation value from the wear characteristic table based on the multiplication value. The wear evaluation value can be accumulated by the accumulation module to obtain the accumulated value.

  According to the present invention, there is provided a multiplication module in which the wear evaluation unit obtains the rotation speed and the current value once every time the DC motor starts operation, and calculates the multiplication value by multiplying the rotation speed and the current value. A wear evaluation module that acquires the wear evaluation value from a wear characteristic table based on the wear characteristic information based on the multiplication value, and the wear evaluation value acquired by the wear evaluation module and the operating time of the DC motor You may provide the integration module which acquires an integrated value.

  In this way, the multiplication module calculates the multiplication value by multiplying the rotational speed by the current value once every time the DC motor starts operating, and the wear evaluation module acquires the wear evaluation value from the wear characteristic table based on the multiplication value. Thus, the processing time of the integrated value can be greatly reduced. Therefore, the load on the friction evaluation means is reduced, and the apparatus can be simplified correspondingly.

  In the present invention, the rotation speed acquisition means may acquire the rotation speed based on a voltage value and a current value of electric power supplied to the DC motor.

  In a DC motor, when the supplied voltage is constant, the rotational speed decreases as the load increases. Further, in a situation where the load is constant, the rotational speed increases as the supply voltage increases. The relationship between this voltage and the rotational speed is determined. Therefore, the rotation speed acquisition means acquires the rotation speed of the DC motor based on the voltage value and current value of the power supplied to the DC motor, so that the rotation speed sensor can be omitted.

  According to the present invention, the DC motor is provided in a vehicle, and the replacement time estimation means can travel until the replacement time is reached based on the travel distance of the vehicle acquired from a travel distance sensor and the estimated replacement time. Notification information indicating a simple distance may be generated.

  According to this, based on the notification information, it is possible to recognize the distance that can be traveled until the time to replace the DC motor is reached, and it is possible to appropriately determine the replacement time of the DC motor. In other words, the replacement time can be easily understood by the user by setting the index indicating the replacement time of the DC motor as the travel distance.

  In the present invention, the DC motor may be provided for driving an oil pump that supplies brake fluid to a vehicle brake device.

  According to this, it is possible to determine the replacement time of the DC motor that drives the oil pump from the notification information. That is, the frequency of stepping on the brake varies depending on the driver. Therefore, although the amount of wear of the brush of the DC motor is not constant and the replacement timing of the DC motor is different, the replacement timing is notified by the notification information, so that an inexpensive DC motor can be used as the drive source of the oil pump. .

It is a block circuit diagram which shows the control system of a DC motor. It is a hydraulic circuit diagram of a brake control unit. It is a block circuit diagram which shows the structure of the control apparatus of 1st Embodiment. It is a figure which shows the flow of control in the control apparatus of 1st Embodiment. It is a flowchart which shows the evaluation process routine of 1st Embodiment. It is the figure which plotted the life value and the wear evaluation value. It is the figure which graphed the rotation speed and current value of the DC motor. It is a block circuit diagram which shows the structure of the control apparatus of 2nd Embodiment. It is a figure which shows the flow of control in the control apparatus of 2nd Embodiment. It is a flowchart which shows the evaluation process routine of 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
A control device 10 that functions as a brake fluid pressure control device of the brake control unit and functions as a DC motor management device that notifies the replacement timing of the DC motor M is configured as shown in FIG.

  In the control device 10, a signal system is formed in which information from the brake pedal sensor 11, the wheel rotation sensor 12, the travel distance sensor 13, and the input / output unit 14 is accessed. Further, the control device 10 includes a solenoid valve control unit 16 that controls a solenoid valve, which will be described later, and a power control unit 17 having a transistor T that controls power supplied to the DC motor M. In the power system of the DC motor M, a shunt resistor 18 for acquiring a current value supplied to the DC motor M and a voltage divided by the shunt resistor 18 (a voltage directly proportional to the current value) are digital signals. And an A / D converter 19 that feeds back to the control device 10.

  Although not shown in the drawings, the DC motor M includes a permanent magnet in a case, a coil in a rotor (rotor), and a brush supported on the case side with respect to a commutator (commutator) that rotates integrally with the rotor. Has a general structure in which the spring is brought into contact with a biasing means such as a spring. The commutator is made of a metal material such as a copper alloy, and graphite or the like is used as a brush. The brush contacts the commutator in a biased state by a spring or the like.

  As shown in FIG. 2, a brake control unit B is configured to apply a braking force to wheels (not shown) of a vehicle such as a passenger car, and a DC motor M is a disc brake provided on each wheel when the brake pedal 1 is operated. The oil pump P that manages the pressure of the brake fluid supplied to the brake device 2 of the mold is driven.

  The brake control unit B realizes antilock brake control (antiskid control), automatic brake control, and the like. The master cylinder 3 operated by the brake pedal 1 is provided with two pressurizing chambers 3A in tandem, and brake fluid from one pressurizing chamber 3A is supplied to the two brake devices for the front wheels via the fluid pressure control unit Bf. 2 is supplied. Similarly, the brake fluid from the other pressurizing chamber is supplied to the two brake devices 2 of the rear wheel via the hydraulic pressure control unit Br. Further, the brake pedal sensor 11 described above is provided so as to detect the depression operation of the brake pedal 1, and the wheel rotation sensor 12 described above is provided in the vicinity of each brake device 2 so as to detect the rotational speed of the wheel.

  The hydraulic control units Bf and Br for the front wheel and the rear wheel have the same configuration, and each of the hydraulic control units Bf and Br includes an electromagnetically operated flow control valve 4 and an electromagnetically operated type. Inlet valve 5, electromagnetically operated outlet valve 6, a plurality of check valves 7, a reservoir 8, and an oil pump P that supplies brake fluid to the upstream side of the inlet valve 5.

  For example, the anti-lock brake control is a well-known control, and the operation mode will not be described in detail. However, when the brake pedal 1 is depressed, the inlet valve 5 and the outlet valve 6 are connected to the electromagnetic valve control unit shown in FIGS. 16 and the DC motor M is controlled by the power control unit 17 shown in FIGS. As a result, even when the brake pedal 1 is continuously operated, the pressure of the brake fluid supplied to the brake device 2 is properly managed, and the side slip of the vehicle is avoided by avoiding the disadvantage that the brake device 2 is maintained in the locked state. It can be avoided. Further, since automatic brake control is also well known and will not be described in detail, for example, the distance between the vehicle traveling ahead and the host vehicle is detected, and the brake control unit automatically turns on an oil pump or the like according to the distance between the vehicles. This is a control that is activated to generate a braking force.

  When the DC motor M is used for a long period of time, the brush is worn, and the proper operation of the DC motor M is hindered by this wear. In order to cope with such inconvenience, the control device 10 estimates the replacement time of the DC motor M and enables notification of the replacement time.

  As the notification described above, for example, the notification information may be displayed on a meter or the like made of a liquid crystal in front of the driver's seat, a display, or the like. However, in this control device 10, the display device 15 is connected to the input / output unit 14 via the connector 14 </ b> A, and the replacement time is displayed on the liquid crystal display or the like of the display device 15 in accordance with a request from the display device 15. The The display device 15 is assumed to be manually connected by personnel who perform work during periodic vehicle inspections and vehicle inspections. During periodic inspections and vehicle inspections, personnel are requested to perform artificially requested operations using the keyboard of the display device 15 or the like. As a result, the travelable distance information is displayed on the display device 15 as notification information indicating the replacement time of the DC motor M. The display device 15 is assumed to be a dedicated terminal for performing various inspections, but may be a general-purpose notebook computer or the like.

〔Control device〕
In order to realize these controls, the control device 10 described above is configured as shown in FIG. That is, the control device 10 includes a CPU, and the brake pedal sensor 11, the wheel rotation sensor 12, the travel distance sensor 13, and the input / output unit 14 are connected to the input / output interface 21 of the CPU. To do. The input / output interface 21 includes an electromagnetic valve control unit 16 that controls each of the flow control valve 4, the inlet valve 5, and the outlet valve 6, a power control unit 17 having a transistor T, and an A / D converter 19. And are connected. Further, the brake fluid control means 22, motor control means 23, interval timer 24, rotation speed acquisition means 25, current value acquisition means 26, wear evaluation means 27, replacement time estimation means 28, travel distance information for the CPU data bus. The acquisition unit 29, the notification unit 30, the storage unit 31, the wear characteristic table 32, and the life value table 33 are connected.

  These brake fluid control means 22, motor control means 23, rotation speed acquisition means 25, current value acquisition means 26, wear evaluation means 27, replacement time estimation means 28, travel distance information acquisition means 29, and notification means 30 are each software. It is configured. These may be configured only by hardware, or may be configured by a combination of software and hardware.

  When the brake pedal 1 is depressed by the brake pedal sensor 11, the brake fluid control means 22 and the motor control means 23 acquire the rotation speed (rotation speed) of a wheel (not shown) by the wheel rotation sensor 12. Anti-lock brake control is realized based on this information. That is, during anti-lock brake control, the brake fluid control means 22 controls the inlet valve 5 and the outlet valve 6 of the brake control unit B described above via the electromagnetic valve control unit 16. Further, during the anti-lock brake control, the motor control means 23 controls the DC motor M via the power control unit 17, and the oil pump P is also controlled.

  The motor control means 23 includes a voltage sensor that detects a voltage applied to the DC motor M, and obtains a motor applied voltage value by this voltage sensor during anti-lock brake control. On the other hand, at the time of automatic brake control, the motor control means 23 sets a target voltage value of electric power supplied to the DC motor M in order to variably control the rotation speed of the DC motor M, and a control signal corresponding to the target voltage value. This is output to the transistor T as the power control unit 17. This control signal is composed of information set by the duty ratio (ratio between ON time and OFF time), and obtains the power of the target voltage by PWM control. In addition, below, the aspect at the time of antilock brake control is mainly demonstrated.

  When the DC motor M is operated, the interval timer 24 is continuously set at a set interval so as to set the timing for acquiring the rotation speed by the rotation speed acquisition means 25 and acquiring the current value by the current value acquisition means 26. To output automatically.

  The rotation speed acquisition means 25 estimates the rotation speed of the DC motor M from the voltage value (motor applied voltage value) acquired by the motor control means 23 and the current value acquired by the current value acquisition means 26 (by calculation). Calculated). That is, in the DC motor M, when the load is high even when a constant voltage is applied, the rotational speed decreases and the current value acquired by the current value acquisition unit 26 increases. On the contrary, when the load is low, the rotational speed increases and the current value acquired by the current value acquisition means 26 decreases. Using such a phenomenon, the rotational speed acquisition means 25 estimates the rotational speed from the voltage value and the current value. The rotation speed acquisition unit 25 may calculate the rotation speed by calculating the voltage value and the current value, or may acquire the rotation speed from the rotation speed table based on the voltage value and the current value.

  In particular, the rotation speed acquired at each set interval assumes a numerical value indicating the rotation speed at each interval. A numerical value indicating the total number of revolutions per interval may be used, but control is performed by acquiring a numerical value indicating the rotational speed in this way, and control is performed by acquiring a numerical value indicating the total rotational speed during the interval. With the thing, the wear characteristic table of the data structure corresponding to these will be used, but the same value is set as the notification information.

  In the present invention, a rotation speed sensor may be provided as the rotation speed acquisition means 25. In order to acquire the voltage value of the electric power supplied to the DC motor M, a part where current flows from the emitter terminal of the transistor T to the DC motor M is obtained. An A / D converter may be provided that performs A / D conversion on the voltage and takes it into the control device 10.

  The current value acquisition unit 26 acquires a signal from the A / D converter 19 as a current value flowing through the brush. Incidentally, the number of rotations of the DC motor M and the value of the current that flows during this rotation can be shown as shown in FIGS. 7 (a) and 7 (b).

  The wear evaluation means 27 includes a multiplication module 27A, a wear evaluation module 27B, and an integration module 27C. The multiplication module 27A calculates a multiplication value by multiplying the rotation speed acquired at each set interval and the current value. Further, the wear evaluation module 27B acquires a wear evaluation value from the wear characteristic table 32 based on the multiplication value. Furthermore, the integration module 27C calculates an integrated value corresponding to the amount of wear of the brush by integrating the wear evaluation value at each set interval.

  The wear characteristic table 32 shows wear characteristics, and is configured as a table having a data structure that can acquire a wear evaluation value from a multiplication value. FIG. 6A shows a graph of the relationship between the life value (L) and the multiplication value (X) of the DC motor M, and FIG. 6B shows the brush wear evaluation value (K). And a multiplication value (X) are shown in a graph.

  The service life value (L) of the DC motor M continues when the DC motor M is operated when the multiplication value (X) is constant (the integrated value of the rotational speed and the current value is constant). ) It depends on the case. That is, FIG. 6A shows that the life value (L) of the DC motor M is longer as the multiplication value (X) obtained by multiplying the rotational speed (N) by the current value (A) is smaller. It is shown that the life value L of the DC motor M is shortened as the value of.

  This means that the smaller the multiplication value (X) obtained by multiplying the rotation speed (N) by the current value (A), the smaller the brush wear amount, and the larger the multiplication value (X), the more brush wear amount of the DC motor M. Means that it will grow. Based on this, the wear evaluation value (K) is graphed as shown in FIG. The wear characteristic table 32 is data in which a wear evaluation value (K) corresponding to the multiplication value (X) is acquired based on the multiplication value (X) of the rotational speed (N) of the DC motor M and the current value (A). It has a structure.

  The contact area of the brush that contacts the commutator is a fixed value, the current density is calculated by dividing the current value by the contact area of the brush, and the multiplication value is calculated by multiplying the current density by the number of rotations of the rotor. Furthermore, a process for obtaining the integrated value is also conceivable. However, since the contact area of the brush is a value determined by the DC motor M, in this control device 10, the contact area of the brush is reflected in the wear characteristic table 32 in advance, and the current is not used without using the current density. The wear evaluation value (K) of the brush can be acquired using the value.

  The replacement time estimation means 28 acquires the initial life value from the life value table 33, and notifies from the initial life value, the integrated value (Y) described above, and the travel distance information acquired by the travel distance information acquisition means 29. The travelable distance information is estimated as information (calculated by calculation). The life value table 33 stores brush initial length data as an initial life value.

  The travel distance information acquisition unit 29 acquires travel distance information from the travel distance sensor 13. In particular, the travel distance sensor 13 outputs information on the total travel distance traveled by the vehicle. However, the travel distance sensor 13 may be configured to output a travel distance per unit time. In this case, the control device 10 needs to calculate the total travel distance of the vehicle from the information from the travel distance sensor 13.

  The notification means 30 includes a notification information storage module 30A and a notification information output module 30B. The notification information storage module 30 </ b> A stores the notification information in the storage unit 31, and the notification information output module 30 </ b> B reads out the distance information stored in the travelable storage unit 31 based on a request from the display device 15 and stores it in the display device 15. Output. The storage unit 31 uses a nonvolatile memory such as an EEPROM.

[Control form]
The outline of the control form of the control device 10 is shown in the block diagram of FIG. 4 and the flowchart of FIG. That is, when the brake pedal 1 is depressed and the DC motor M reaches the operating state, the rotation speed acquisition means 25 acquires the rotation speed (N) of the rotor of the DC motor M at every timing set by the interval timer 24. The current value (A) is acquired by the current value acquisition means 26. The multiplication value (X) is calculated by multiplying the acquired rotation speed (N) and current value (A) by the multiplication module 27A of the wear evaluation means 27 for each interval, and the multiplication value is calculated from the wear characteristic table 32 for each interval. The wear evaluation module 27B acquires the wear evaluation value (K) corresponding to (X). The operation of integrating the acquired wear evaluation value (K) with the integrated value (Y) (initial value is 0) is performed by the integrating module 27C of the wear evaluating unit 27, and this wear evaluating unit 27 stores it in the storage unit 31 (# 101- # 105 steps).

  In this control, a relatively short time of less than 0.1 seconds is set as an interval set by the interval timer 24. The interval may be any time, and control for obtaining the rotational speed (N) of the DC motor M and the current value (A) supplied to the DC motor M is essential at each interval. The calculation of the value (X), the acquisition of the wear evaluation value (K), and the calculation of the integrated value (Y) may be performed after the DC motor M is stopped.

  As described above with reference to FIG. 6B, the wear evaluation value (K) increases as the multiplication value (X) increases, and this wear evaluation value (K) corresponds to the amount of wear of the brush. Therefore, when the integrated value (Y) increases, the wear amount of the brush also increases.

  Next, the replacement time estimation means 28 acquires the integrated value (Y) from the storage unit 31, acquires the initial life value from the life value table 33, and travel distance information (vehicle information) acquired by the travel distance sensor 13. Total travel distance) is acquired, and travelable distance information is estimated based on these (calculated by calculation). The notification information storage module 30A of the notification means 30 stores this travelable distance information as notification information in the storage unit 31 (steps # 106 and # 107).

  As described above, the initial life value is a unique value of the DC motor M corresponding to the length of the brush. Further, when the travelable distance information estimated by the replacement time estimating means 28 is, for example, about half of the travel distance information (total travel distance of the vehicle), the current total travel distance of the vehicle is used as a reference. Thus, a travel distance equal to the total travel distance is calculated as travelable distance information and stored in the storage unit 31 as notification information.

  Next, when the display device 15 is connected to the connector 14 </ b> A of the input / output unit 14 and there is a request for notification information (travelable distance information) from the display device 15, notification information stored in the storage unit 31. The notification information output module 30B reads (travelable distance information) and displays the numerical value on the display device 15 (steps # 108 and # 109).

  Then, the travelable distance information is displayed as notification information on the display of the display device 15 so that the replacement time of the DC motor M can be determined based on the travel distance of the vehicle. It can be exchanged.

  As described above, in the control device 10 of the first embodiment, when the DC motor M is operated, the rotational speed (N) of the DC motor M and the current value (A) supplied to the DC motor M with a relatively short sampling period. And get. Further, a multiplication value (X) obtained by multiplying the acquired rotation speed (N) and the current value (A) is calculated, and the wear evaluation value (K) is acquired from the wear characteristic table 32. Furthermore, a new integrated value (Y) reflecting the operation of the DC motor M is obtained by integrating this wear evaluation value (K) with an existing integrated value (initial value is 0).

  The wear evaluation value (K) indicates the degree of wear of the brush of the DC motor M (the amount of brush wear (length) per unit time), and an integrated value obtained by integrating the wear evaluation value (K) with the usage time. The value (Y) corresponds to the total wear amount (length) of the brush. Therefore, the current length of the brush is obtained by subtracting the integrated value (Y) from the initial life value (the initial length of the brush). Although it is conceivable to output time information corresponding to the usable life of the DC motor M from the current length of the brush, in the control device 10 of the present invention, the current length of the brush and the travel distance information (total travel distance information) ) Can be estimated (calculated) from the above information, and can be stored as notification information.

  The control device of the present invention does not output the degree of wear of the brush, but stores travelable distance information as a numerical value that allows the vehicle to travel until the DC motor M needs to be replaced, and displays it as necessary. The display form is set to do. For this reason, it is possible to appropriately grasp whether or not the DC motor M needs to be replaced at an arbitrary timing. In particular, since it is possible to grasp the replacement timing of the DC motor M at the time of regular inspection and inspection of the vehicle, it is possible to replace the DC motor M before the vehicle has traveled for this travelable distance.

When the DC motor M is replaced, information on the total travel distance of the vehicle at the time of replacement is stored as an initial value, and the travelable distance information estimated by calculation by the replacement time estimation means 28 is the initial value. Is estimated (calculated) on the basis of.
The brake control unit B described in the present embodiment executes not only the antilock brake control but also the automatic brake control as described above. In such a brake control unit, for example, compared to a brake control unit that executes only anti-lock brake control, there are many occasions when a direct current motor for driving an oil pump is operated, so that a long motor life is required, and as a result As for management, higher accuracy is required. The direct current motor management device of the present invention can meet such a request at a higher level and can be said to be particularly useful.

[Second Embodiment]
In the second embodiment, the hardware of the control device 10 is not different from that of the first embodiment, and the configuration for realizing the control and the control form are different. In the second embodiment, those having the same functions as those in the first embodiment are given the same numbers and symbols as those in the first embodiment.

  As shown in FIGS. 8 and 9, the control system of the control device 10 includes a sampling timing setting unit 35 instead of the interval timer 24 of the first embodiment, and the other configurations are the same as those of the first embodiment. ing.

  The sampling timing setting unit 35 outputs a timing signal for performing the acquisition of the rotational speed by the rotational speed acquisition means 25 and the acquisition of the current value by the current value acquisition means 26 only once every time the DC motor M starts to operate. Specifically, as shown in FIG. 7A, the rotational speed (N1) at the timing (t1) when the set time (an example of the operation information) has elapsed from the start of the operation of the DC motor M is acquired, and FIG. ), The current value (A1) at the timing (t1) is acquired.

  As shown in FIG. 7, the characteristics of the rotational speed (N) and the current value (A) at the time from the start of operation of the direct current motor M to the stop thereof are substantially determined. Therefore, even if the wear evaluation value (K) is acquired based on the multiplication value (X) of the rotation speed (N1) and the current value (A1), the operating time of the DC motor M with respect to the wear evaluation value (K). By calculating by multiplying the operating time coefficient that reflects, the rotation speed (N) and the current value (A) are acquired at the set interval as in the first embodiment, and the multiplication value (X) is calculated. Furthermore, the integrated value (Y) reflecting the operating time can be acquired without performing the calculation for calculating the integrated value (Y).

[Control form]
The outline of the control form of the control device 10 is shown in the block diagram of FIG. 9 and the flowchart of FIG. That is, when the brake pedal 1 is depressed and the DC motor M reaches the operating state, the rotational speed (N1) is acquired by the rotational speed acquisition means 25 only once at the timing (t1) set by the sampling timing setting unit 35. The current value acquisition unit 26 acquires the current value (A1). In addition, the multiplication value (X) is calculated by multiplying the acquired rotation speed (N1) and current value (A1) by the multiplication module 27A of the wear evaluation means 27, and corresponds to the multiplication value (X) from the wear characteristic table 32. The wear evaluation module 27B acquires the wear evaluation value (K) to be performed (steps # 201 to # 204).

  The timing (t1) is set by the sampling timing setting unit 35 such that the rotational speed of the DC motor M becomes stable after the DC motor M starts operating. Thereby, by acquiring the rotation speed (N1) and the current value (A1) when the DC motor M is operated, it is not necessary to perform sampling a plurality of times. The timing (t1) is preferably the time when the rotational speed of the DC motor M is stabilized.

  Next, in the integrating module 27C of the wear evaluating means 27, the wear evaluation value (K) is multiplied by an operation time coefficient based on the operation time of the DC motor M, whereby integration is performed simultaneously with the correction of the wear evaluation value (K). . Thereby, the integrated value (Y) obtained by adding the wear evaluation value (K) within the operation time of the DC motor M is acquired. An operation for calculating the integrated value (Y) by integrating the integrated value (Y) (initial value is 0) is performed by the integrating module 27C of the wear evaluation means 27 and stored in the storage unit 31 (step # 205).

  The operating time coefficient described above is set to a larger value as the operating time of the DC motor M is longer, and is converted to a value (integrated value) reflecting the operating time of the DC motor M with respect to the wear evaluation value (X). Realize processing.

  Next, the replacement time estimation means 28 acquires the integrated value (Y) from the storage unit 31, acquires the initial life value from the life value table 33, and travel distance information (vehicle information) acquired by the travel distance sensor 13. Total travel distance) is acquired, and travelable distance information is estimated based on these (calculated by calculation). The notification information storage module 30A of the notification unit 30 stores this travelable distance information as notification information in the storage unit 31 (steps # 206 and # 207).

  As described above, the initial life value is a specific value of the DC motor M corresponding to the initial brush length. Further, the travelable distance information estimated by the replacement time estimating means 28 is calculated as a travel distance until the end of the service life based on the current total travel distance of the vehicle, and is stored in the storage unit 31 as notification information. Will be.

  Next, when the display device 15 is connected to the connector 14 </ b> A of the input / output unit 14 and there is a request for notification information (travelable distance information) from the display device 15, notification information stored in the storage unit 31. The notification information output module 30B reads (travelable distance information) and displays the numerical value on the display device 15 (steps # 208 and # 209).

  By displaying the travelable distance information as notification information on the display of the display device 15 or the like, it is possible to determine the replacement time of the DC motor M based on the travel distance of the vehicle, and if necessary, replace the DC motor M. Yes.

  As described above, in the control device 10 of the second embodiment, every time the operation of the DC motor M starts, the rotational speed (N1) of the DC motor M and the current value (A1) supplied to the DC motor M at a predetermined sampling timing. And get only once. Then, a multiplication value (X) obtained by multiplying the acquired rotation speed (N1) and the current value (A1) is calculated, and the wear evaluation value (K) is acquired by the multiplication value (X). The wear evaluation value (K) is corrected by a time correction coefficient corresponding to the operating time of the DC motor M, and at the same time, a process for obtaining an integrated value (Y) is performed, and this integrated value (Y) is added to the existing integrated value. Thus, a new integrated value (Y) reflecting the operation of the DC motor M is obtained.

  The wear evaluation value (K) indicates the degree of wear of the brush of the DC motor M (the amount of brush wear (length) per unit time), and an integrated value obtained by integrating the wear evaluation value (K) with the usage time. The value (Y) corresponds to the total wear amount (length) of the brush. Therefore, the current length of the brush is obtained by subtracting the integrated value (Y) from the initial life value (the initial length of the brush). Although it is conceivable to output time information corresponding to the usable life of the DC motor M from the current length of the brush, in the control device 10 of the present invention, the current length of the brush and the travel distance information (total travel distance information) ) Can be estimated (calculated) from the travel distance information, and the travel distance information can be stored as notification information.

  The control device of the present invention does not output the degree of wear of the brush, but stores travelable distance information as a numerical value that allows the vehicle to travel until the DC motor M needs to be replaced, and displays it as necessary. Since the display form is set to do so, it is possible to appropriately grasp whether or not the DC motor M needs to be replaced at an arbitrary timing. In particular, since it is possible to grasp the replacement timing of the DC motor M at the time of regular inspection and inspection of the vehicle, it is possible to replace the DC motor M before the vehicle has traveled for this travelable distance.

[Another embodiment]
In addition to the above-described embodiment, the present invention may be configured as follows (in this another embodiment, the same function and number as those in the above embodiment are used for those having the same functions as those in the above embodiment). Is attached).

(A) The direct current motor management device of the present invention is not limited to the direct current motor for driving the oil pump P in the brake control unit, but may be used for managing the direct current motor used in a general device. .

(B) The replacement time estimation means may generate usable time information in addition to the travelable distance information that the vehicle can travel as notification information, and combines the travelable distance information and the usable time information. Information may be generated.

(C) As a notification system for outputting information from the notification means, a speaker that outputs sound may be used, or meters provided in a meter panel of a vehicle may be used as the notification system. As a specific example, an apparatus provided with a liquid crystal display as a meter panel is configured to display information of the notification means by selecting a specific mode.

  INDUSTRIAL APPLICABILITY The present invention can be used for an apparatus having a device including a DC motor to which power is supplied via a brush.

2 Braking device 13 Travel distance sensor 25 Rotational speed acquisition means 26 Current value acquisition means 27 Wear evaluation means 27A Multiplication module 27B Integration module 27C Wear evaluation module 29 Replacement time estimation means 32 Wear characteristic table M DC motor P Oil pump

Claims (7)

A DC motor management device for managing the life of a DC motor having a brush,
A rotation speed acquisition means for acquiring the rotation speed of the DC motor; and a current value acquisition means for acquiring a current value supplied to the DC motor;
Wear evaluation means for obtaining a wear evaluation value from the brush wear characteristics of the DC motor based on a multiplication value obtained by multiplying the rotation speed by the current value, and corresponding to the wear amount of the brush by integrating the wear evaluation value. DC motor management device that outputs the integrated value.   The DC motor management device according to claim 1, further comprising a replacement time estimation unit that estimates a replacement time based on the integrated value.   The wear evaluation unit calculates a multiplication value by multiplying the rotation speed acquired by the rotation speed acquisition unit at each set interval by the current value acquired by the current value acquisition unit at each set interval. A wear evaluation module for acquiring the wear evaluation value from a wear characteristic table based on the wear characteristic information based on the multiplication value calculated for each set interval; and the wear evaluation value acquired by the wear evaluation module. The DC motor management device according to claim 1, further comprising an integration module for integrating.   The wear evaluation means includes a multiplication module that obtains a rotation speed and a current value once every time the DC motor starts operation, and calculates the multiplication value by multiplying the rotation speed and the current value. A wear evaluation module for acquiring the wear evaluation value from a wear characteristic table based on the wear characteristic information based on the value, and acquiring the integrated value from the wear evaluation value acquired by the wear evaluation module and the operating time of the DC motor The DC motor management device according to claim 1, further comprising an integrating module that performs the operation.   The DC motor management device according to any one of claims 1 to 4, wherein the rotation speed acquisition unit acquires the rotation speed based on a voltage value and a current value of electric power supplied to the DC motor.   The DC motor is provided in the vehicle, and the replacement time estimation means indicates the distance that can be traveled until the replacement time is reached based on the vehicle travel distance acquired from the travel distance sensor and the estimated replacement time. The DC motor management device according to any one of claims 2 to 5, which generates notification information.   The DC motor management device according to claim 6, wherein the DC motor is provided for driving an oil pump that supplies brake fluid to a brake device of a vehicle.

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