JP3331723B2 - Step motor control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor control device for controlling a stepping motor, and more particularly to a stepping motor control capable of detecting whether a calculation result of the number of steps matches an actual number of steps. Related to the device.

[0002]

2. Description of the Related Art Conventionally, central processing means such as a manager ECU for transmitting control information of a step motor is connected to the central processing means via a signal line, and transmitted from the central processing means via a signal line. And a terminal processing means such as a step motor module for driving a step motor based on the control information. In this type of step motor control device, control information such as a target number of steps is sent from a central processing unit to a terminal processing unit, and the terminal processing unit outputs a drive signal to the step motor in accordance with the control information.

[0003]

However, in this type of apparatus, the terminal processing means calculates the current number of steps of the step motor in accordance with the drive signal output by itself.
Therefore, if the terminal processing means is reset or its power supply is cut off, the current number of steps of the stepping motor is lost or the number of steps is calculated incorrectly. Then, the actual number of steps of the step motor cannot be brought close to the target number of steps, and good control may not be performed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a step motor control device capable of satisfactorily detecting whether or not an abnormality has occurred in the number of steps of a step motor calculated by a terminal processing means such as a step motor module. It was made as.

[0005]

Means for Solving the Problems According to the first aspect of the present invention, which has been made to achieve the above object, as shown in FIG. 4, a central control unit having control information transmitting means for transmitting control information of a step motor is provided. Processing means, and a target step connected to the central processing means via a signal line and corresponding to control information transmitted from the control information transmitting means via the signal line.
Compare the number of steps and the current number of steps to match them
And a terminal processing means having a step motor driving means for driving the step motor, wherein the terminal processing means is provided in the terminal processing means, based on a driving state of the step motor by the step motor driving means. The current step number calculating means for calculating the current step number of the step motor, and the current step number of the step motor calculated by the current step number calculating means provided in the terminal processing means, via the signal line. A current step number transmitting means for transmitting to the central processing means, and a step number storing means provided in the central processing means for storing a current step number of the step motor transmitted from the current step number transmitting means, The step number provided in the central processing means and stored in the step number storage means. A storage step number transmitting means for transmitting the step number of the motor to the terminal processing means via the signal line; and a step number of the step motor provided in the terminal processing means and transmitted from the storage step number transmission means. And an abnormality detecting means for comparing the number of steps of the step motor calculated by the current step number calculating means, and detecting an abnormality in the step number calculation result when the two step numbers do not match. The gist of the present invention is a step motor control device.

According to a second aspect of the present invention, as shown in FIG. 5, when the abnormality detecting means detects an abnormality in the step number calculation result, the stepping motor is driven. The gist of the present invention is a step motor control device according to claim 1, further comprising a drive prohibiting means for prohibiting the driving.

Further, the invention according to claim 3 is characterized in that the step motor opens and closes an idle speed control valve of an internal combustion engine. I have.

[0008]

According to the first aspect of the present invention, the current step number calculating means calculates the current step number of the step motor based on the driving state of the step motor by the step motor driving means. The number transmitting means transmits the number of steps to the central processing means via a signal line. Then, the step number storage means stores the transmitted step number, and the storage step number transmission means transmits the step number of the step motor stored in the step number storage means to the terminal processing means via a signal line. I do.

If no power failure, reset, etc. are performed, the number of steps of the step motor transmitted from the storage step number transmitting means to the terminal processing means and the number of steps of the step motor calculated by the current step number calculating means are calculated. It should match the number. However, if a power failure, reset, or the like is performed in the terminal processing means between the time when the current step number transmitting means transmits the step number and the time when the stored step number transmitting means receives the step number, the two step numbers are different. There is. Therefore, the abnormality detecting means compares the two step numbers, and detects an abnormality in the step number calculation result when the two step numbers do not match. For this reason, whether or not there is an abnormality in the calculation result of the number of steps of the terminal processing means due to a power failure, a reset, or the like is properly detected.

Further, according to the second aspect of the present invention, when the abnormality detecting means detects the abnormality of the step number calculation result,
The drive inhibiting means inhibits the drive of the step motor. Therefore, malfunction of the step motor can be reliably prevented. Further, in the invention according to claim 3, the step motor opens and closes an idle speed control valve (hereinafter, referred to as ISCV) of the internal combustion engine. If the step motor driving the ISCV malfunctions, the output of the internal combustion engine may change suddenly. In the present invention, since the invention described in claim 1 or 2 is applied to an ISCV step motor, such a sudden change in the output of the internal combustion engine can be favorably prevented.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram schematically illustrating a configuration of the step motor control device according to the embodiment. The stepping motor control device according to the present embodiment is provided in an internal combustion engine for an automobile.
This is a device for controlling the step motor 1 for opening and closing the SCV.

As shown in the figure, the step motor control device of the present embodiment includes a step motor module 3 as a terminal processing means for driving the step motor 1 and control information such as a target step St in the step motor module 3. It has a manager ECU 5 as central processing means for transmitting via the signal line 4.

The stepping motor module 3 includes a central processing unit (CP) for executing various arithmetic processing.
U) 31a, a read-only memory (ROM) 31b storing programs and the like, a random access memory (RAM) 31c in which data and the like are written as needed, and C
An arithmetic processing unit 31 having a bus 31d for electrically connecting the PU 31a, the ROM 31b, and the RAM 31c to enable data input / output;
Reference numeral 31a transmits a drive signal to the step motor 1 via the step motor driver 33.

The CPU 31a inputs and outputs various data described later to the signal line 4 via the communication IC 35 and the communication driver receiver 37. The communication IC 35 is a CPU
The communication driver receiver 37 transforms the data output by the communication 31a into a predetermined format for communication.
Amplifies the signal level of the data input / output from / to the communication level.

On the other hand, the manager ECU 5 also has a CPU 51
a, a ROM 51b, a RAM 51c, and a bus 51d. The CPU 51a of the processor 51 inputs and outputs various data to and from the signal line 4 via the communication IC 55 and the communication driver receiver 57. I have.
Further, the CPU 51a is supplied with detection signals from various sensors (not shown) for detecting the operating state of the internal combustion engine, such as a rotation speed sensor and a water temperature sensor.
a calculates a target step St of the step motor 1 based on these signals.

Next, step motor control processing executed by the manager ECU 5 and the CPUs 51a and 31a of the step motor module 3 will be described. FIG.
FIG. 3 is a flowchart illustrating a control process on the manager ECU side executed by the PU 51a, and FIG. 3 is a flowchart illustrating a control process on the step motor module side executed by the CPU 31a. As will be described later, in this step motor control process, the step motor module 3 sends the current step S2 calculated based on the driving state of the step motor 1 to the manager ECU 5, and
The CU 5 is currently performing a process of returning the value S1 storing the step S2 to the step motor module 3.

The CPU 51a starts the processing shown in FIG. 2 when the current step S2 is transmitted via the signal line 4. When the process is started, first, in step 101, the CPU 31
The current step S2 transmitted from a through the signal line 4 is read. In the following step 103, the read current step S2 is substituted for the current step S1 as a stored value on the manager ECU 5 side, and the routine proceeds to step 105. In step 105, a known process for calculating a target step St of the step motor 1 is executed based on the detection signals of the various sensors described above. In the following step 107,
The calculated target step St and the above-described current step S1
Is transmitted to the step motor module 3 via the signal line 4, and the process is temporarily terminated.

On the other hand, the CP of the step motor module 3
The U31a starts the processing of FIG. 3 when the target step St and the current step S1 are input via the signal line 4. When the process is started, first, the transmitted target step St and the current step S1 are read. In the following step 203, it is determined whether or not a current step S2, which will be described later, calculated in the previous processing is equal to the read current step S1. When S1 ≠ S2 (Step 203: N
O) proceeds to step 205 as it is, and executes the current step S2 calculated in the previous processing via the signal line 4 to the CPU 5
1a. When S1 = S2 (step 2
03: YES) moves to steps 207 to 219,
The step motor 1 is driven as follows.

In step 207, it is determined whether the current step S2 is smaller than the target step St. If an affirmative determination is made here, the process sequentially proceeds to steps 209 and 211, a drive signal is output so as to rotate the step motor 1 forward by one step, and the current step S2 is incremented by one. Also, S2
If ≧ St (step 207: NO), step 21
Then, it is determined whether or not S2> St. If an affirmative determination is made here, the process sequentially proceeds to steps 215 and 217, a drive signal is output so as to reverse the step motor 1 by one step, and the current step S2 is decremented by one. Further, if a negative determination is made in step 213, that is, if S2 = St, a drive signal is output in step 219 so as to hold the rotational position of the step motor 1, and the process proceeds to step 205. That is, at this time, the current step S2 does not change.

As described above, the CPU 31a outputs a drive signal to the step motor 1 so that the current step S2 matches the target step St (steps 209 and 21).
5, 219), the current step S2 is corrected in parallel with the output of the drive signal (steps 211, 217). In addition, this series of step motor drive processing (step 20)
7 to 219), the current step S2 is changed to the manager E
The current step S1 transmitted to the CU 5 and sent back together with the target step St at the next processing (the value stored in the manager ECU 5 at the current step S2) is the same as the value stored as the current step S2 in the previous processing. Is determined (step 203). Then, when S1 = S2, it is determined to be normal, and the processing of steps 207 to 219 is executed. Conversely, if S1 ≠ S2, there is a possibility that the current value of step S2 may be abnormal due to a power failure, reset, or the like, so that the processing of steps 207 to 219 is not executed.

For this reason, the stepping motor control device of the present embodiment can satisfactorily detect whether or not an abnormality has occurred in the step S2, and furthermore, if an abnormality has occurred, the driving of the stepping motor 1 is stopped. As a result, malfunction can be prevented. Further, in the above embodiment, the malfunction of the ISCV step motor 1 of the internal combustion engine for a vehicle can be prevented, so that a sudden change in the output of the internal combustion engine can be satisfactorily prevented, and the runaway of the vehicle can be prevented very well. Can be. When the internal combustion engine is once stopped and restarted, the value of the current step S2 is set to a predetermined initial value together with the rotation angle of the step motor 1, and the normal current step S2 is again set.
Can be performed.

In the processing of FIGS. 2 and 3, step 103 is stored in the step number storage means.
7 is the storage step number transmission means and the control information transmission means, step 203 is the abnormality detection means and the drive inhibition means, steps 207, 209, 213, 215 and 219 are the step motor driving means, and steps 211 and 217 are the current. Step 205 is processing corresponding to the step number calculating means, and step 205 is processing corresponding to the current step number transmitting means.

Further, in the above embodiment, when S1 ≠ S2,
Although the driving of the step motor 1 is simply stopped, the driver may be notified of the abnormality by lighting an abnormality lamp or the like. Then, the driver can cope by stopping idling when the abnormal lamp is lit. Further, the drive of the step motor 1 may be continued by merely turning on the abnormal lamp. In this case as well, the driver can deal with the abnormality. Further, when S1 ≠ S2, the step motor 1 may be driven until the mechanical stop (the ISCV is fully opened or fully closed), and the current step S2 may be newly calculated based on the position. In this case, the control of the step motor 1 can be continued by calculating the correct current step S2 automatically.

In the above-described embodiment, the CPU 51a transmits the target number of steps St as control information. However, various other control information such as the amount of increase or decrease of the number of steps and the rate of increase or decrease of the number of steps are used as the control information. It is also possible to configure so as to control the step motor 1 by transmitting. Also,
The CPU 31a can also transmit information such as the amount of increase / decrease of the number of steps and the speed of increase / decrease of the number of steps to the CPU 51a to detect an abnormality of the step motor 1. However, in this case, it is necessary for the CPU 51a to calculate the current step S2 based on the transmitted information.

[0025]

As described above in detail, according to the first aspect of the present invention, the number of steps of the step motor transmitted from the storage step number transmitting means and the number of steps of the step motor calculated by the current step number calculating means are obtained. , It is possible to satisfactorily detect whether or not there is an abnormality in the step number calculation result of the terminal processing means due to a power failure, reset, or the like. Therefore, if this detection result is applied to various controls or notified to the user, malfunction of the device driven by the step motor can be prevented well.

According to the second aspect of the present invention, the drive of the step motor is prohibited when an abnormality in the calculation result of the number of steps is detected, so that the malfunction of the step motor can be more reliably prevented. Further, according to the third aspect of the present invention, it is possible to prevent a malfunction of the step motor and to prevent a sudden change in the output of the internal combustion engine.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically illustrating a configuration of a step motor control device according to an embodiment.

FIG. 2 is a flowchart illustrating a manager ECU side control process of the embodiment.

FIG. 3 is a flowchart illustrating a step motor module side control process of the embodiment.

FIG. 4 is a diagram illustrating a configuration example of the invention according to claim 1;

FIG. 5 is a diagram illustrating a configuration example of the invention according to claim 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Step motor 3 ... Step motor module 4 ... Signal line 5 ... Manager ECU31,51
… Calculation processing unit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-10186 (JP, A) JP-A-1-122394 (JP, A) JP-A-62-96757 (JP, A) JP-A-5-96 146198 (JP, A) JP-A-1-174295 (JP, A) JP-A-5-161394 (JP, A) JP-A-63-95895 (JP, A) JP-A-3-57845 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H02P 8/00 B60R 16/02

Claims (3)

(57) [Claims] 1. A central processing unit having control information transmitting means for transmitting control information of a step motor, connected to the central processing unit via a signal line, and connected from the control information transmitting means via the signal line. Compare the target number of steps and the current number of steps corresponding to the transmitted control information
And a terminal processing means provided with a step motor driving means for driving the step motor so that the two are matched with each other. A step motor control device comprising: a step motor provided in the terminal processing means; A current step number calculating means for calculating a current step number of the step motor based on the driving state of the step motor; and a current step number of the step motor calculated by the current step number calculating means provided in the terminal processing means. A current step number transmitting means for transmitting to the central processing means via the signal line; and a current step number of the step motor transmitted from the current step number transmitting means provided in the central processing means. Step number storage means, provided in the central processing means, and storing the step number A storage step number transmitting means for transmitting the step number of the step motor stored in the stage to the terminal processing means via the signal line; and a transmission step number provided in the terminal processing means and transmitted from the storage step number transmission means. Abnormality detection means for comparing the number of steps of the step motor with the number of steps of the step motor calculated by the current step number calculation means, and detecting an abnormality in the step number calculation result when the two step numbers do not match; A step motor control device comprising: 2. The method according to claim 1, further comprising: when the abnormality detecting means detects an abnormality in the step number calculation result,
2. The step motor control device according to claim 1, further comprising a drive inhibiting means for inhibiting the drive of the step motor. 3. The step motor control device according to claim 1, wherein the step motor opens and closes an idle speed control valve of the internal combustion engine.