JPH11257136A - Step motor controlling method for auxiliary air regulating valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any bounceback phenomenon from occurring by making at least one side of driving frequency and driving voltage of a step motor smaller than in time of auxiliary air quantity control at the time of initialization accommodating the operating pulse number of the step motor being related to an auxiliary air regulating valve, to a valve opening position. SOLUTION: In a device which controls the opening of an idle adjusting valve V or an auxiliary air regulating valve with a step motor M in a bypass passage 4 bypassing a throttle valve 3, for example, just after an ignition switch is interrupted, an initializing process accommodating the operating pulse nor of the step motor M, to an opening position of the idle adjusting valve V is executed. At this process, the idle adjusting valve V is driven to either of both valve closing and opening limits of the idle adjusting valve V. At this time, at least one side of driving frequency and driving voltage of the step motor M is made smaller than in time of auxiliary air quantity control by the idle adjusting valve V, whereby any bounceback phenomenon is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an operation pulse number of a step motor connected to an auxiliary air control valve for adjusting an opening degree of a bypass passage bypassing a throttle valve, and an opening position of the auxiliary air control valve. The present invention relates to a step motor control method for an auxiliary air control valve, in which, when performing an initialization process for operating the auxiliary air control valve, the step motor is driven to drive the auxiliary air control valve to one of a valve closing limit and a valve opening limit.

[0002]

2. Description of the Related Art Conventionally, such a control method is known, for example, from JP-B-63-42106 and JP-B-5-543.

[0003]

SUMMARY OF THE INVENTION In the above prior art,
Without using a potentiometer or a reference position sensor such as a limit switch, the auxiliary air control valve can be fully closed or fully opened so that the opening of the auxiliary air control valve and the number of operation pulses of the step motor can be easily associated. A pulse signal of a fixed number of pulses is given to the step motor to drive to the position, and the initialization process of resetting the operation pulse number of the step motor so that the fully closed or fully opened position is set as the reference position is performed immediately after the ignition switch is shut off, etc. I want to run.

When the auxiliary air control valve is driven to either the valve closing limit or the valve opening limit, a phenomenon in which the number of steps of the step motor jumps due to the magnetic pole structure of the step motor, a so-called bounce back phenomenon, occurs. Arises
The auxiliary air control valve may move out of its closing or opening limits.

[0005] This bounce-back phenomenon occurs when the step motor is operated to drive the auxiliary air control valve to one of the valve closing limit and the valve opening limit, and the rotor rotates in the reverse direction at the time of the specific excitation pole of the step motor. This is due to the fact that the behavior of the stepping motor, which tends to stabilize, occurs due to the structure of the stepping motor, and occurs when the rotor has a sufficient inertial force at the time of the reverse rotation of the rotor and the reverse rotation timing coincides with the drive frequency. .

Even if the initialization process is performed in a state where such a bounce-back phenomenon occurs, the number of operation pulses of the step motor and the opening position of the auxiliary air control valve cannot be correctly associated with each other. Kosho 63-
No. 42106 does not disclose a measure for coping with the bounceback phenomenon. In addition,
In Japanese Patent Publication No. 543, the bounce-back phenomenon is prevented by controlling the excitation pattern and timing of the step motor, but the control is complicated.

The present invention has been made in view of such circumstances, and when performing an initialization process for associating the number of operation pulses of a step motor with the opening position of the auxiliary air control valve, a bounce method is used in a simple manner. It is an object of the present invention to provide a stepping motor control method for an auxiliary air regulating valve which can avoid the occurrence of a back phenomenon and can accurately associate the operation pulse and the opening position.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, an operation of a step motor connected to an auxiliary air control valve for adjusting an opening of a bypass passage bypassing a throttle valve is provided. In performing an initialization process for associating the number of pulses with the opening position of the auxiliary air control valve, a step motor is operated so as to drive the auxiliary air control valve to one of the valve closing limit and the valve opening limit. In the step motor control method for the auxiliary air control valve, when driving the auxiliary air control valve to one of the valve closing limit and the valve opening limit during the execution of the initialization process, at least one of the drive frequency and the drive voltage of the step motor is adjusted. It is characterized in that it is made smaller than at the time of executing the auxiliary air amount control by adjusting the opening degree of the auxiliary air control valve.

The inventor of the present invention has investigated the bounce-back phenomenon, and has found that the natural frequency of the operating section including the rotor of the step motor, that is, the weight of the operating section,
It has been found that the frictional resistance at the time of driving the auxiliary air control valve, the driving thrust of the stepping motor, that is, the driving voltage, and the driving frequency that affects the resonance are factors that cause the bounce-back phenomenon. , Can not be changed due to the configuration of the step motor and the auxiliary air control valve, whereas, can be changed. Therefore, the bounce-back phenomenon can be prevented by a simple control in which at least one of the drive frequency and the drive voltage is made smaller than when the auxiliary air amount control is performed by adjusting the opening of the auxiliary air control valve. . In addition, when only the drive frequency is reduced, the drive voltage may remain at a relatively high value, and the correspondence between the opening degree of the auxiliary air control valve and the number of operation pulses of the step motor may be disturbed due to the decrease in the drive voltage. (Step-out) does not occur. When only the drive voltage is reduced, the control frequency can be increased because the drive frequency can be kept high. Further, if both the drive voltage and the drive frequency are reduced, the occurrence of the bounce-back phenomenon can be more reliably prevented. At this time, the drive voltage is reduced to a value at which the step-out does not occur. be able to.

According to another aspect of the present invention, the number of operating pulses of a step motor connected to an auxiliary air control valve for adjusting an opening degree of a bypass passage bypassing a throttle valve is provided. When performing the initialization process for matching the opening position of the air control valve, the auxiliary air control valve is operated to operate the step motor so as to drive the auxiliary air control valve to either the valve closing limit or the valve opening limit. In the step motor control method, the drive voltage supplied to the step motor immediately before the step motor is operated to drive the auxiliary air regulating valve to one of the valve closing limit and the valve opening limit during the execution of the initialization process. The drive frequency is determined based on the detected value, and the stepping motor is operated at the determined drive frequency to determine the valve closing limit. And drives the auxiliary air control valve to either the open limit and.

By the way, the present inventor measured the occurrence of the bounce-back phenomenon by changing the driving voltage and the driving frequency, respectively. As a result, the result shown in FIG. 4 was obtained, and the result shown in FIG. Based on this, it is possible to determine the drive frequency at which the bounce-back phenomenon does not occur according to the detected value of the drive voltage. The drive voltage is reduced due to the life and deterioration of the battery, the temperature drop in the cold season, the starter switch is turned on, the engine load, and the like, and is increased at the time of overcharging. Since the drive voltage is detected immediately before the step motor is operated to drive the auxiliary air control valve to one of the valve closing limit and the valve opening limit according to the method of the present invention, the actual fluctuation voltage when executing the initialization process The bounce-back phenomenon can be prevented by determining the optimum driving frequency according to the above.

According to a third aspect of the present invention, in addition to the method of the second aspect, in determining the drive frequency, when the detected value of the drive voltage exceeds a first set voltage, the auxiliary air control valve is turned off. When the drive frequency is determined to be smaller than the drive frequency at the time of execution of the auxiliary air control amount which is set in advance to execute the auxiliary air amount control by adjusting the opening degree, and when the detected value of the drive voltage is equal to or lower than the first set voltage, The driving frequency is set to a value equal to the driving frequency when the auxiliary air amount control is executed.

According to FIG. 4, the drive frequency FU at the time of executing the auxiliary air amount control is set to be relatively large in order to increase the control speed, and if it is too large, there is a risk of step-out when the battery voltage drops extremely. Based on, for example, 200P
When the drive voltage is set to a certain voltage V1 in a state where the drive voltage is set to PS.
(For example, 14 V), the driving frequency F1 (for example, 100 PP
In S), the bounce-back phenomenon does not occur, and when the drive voltage is equal to or lower than the voltage V1, the bounce-back phenomenon does not occur even at the drive frequency equal to the drive frequency FU during the execution of the auxiliary air amount control. Therefore, the voltage V1 is defined as a first set voltage, and the drive frequency when the detected value of the drive voltage exceeds the first set voltage V1 is defined as the drive frequency F1, so that the drive frequency F1 is determined. By executing the process according to the method, it is possible to prevent the bounce-back phenomenon from occurring by operating the stepping motor at the optimum driving frequency.

According to a fourth aspect of the present invention, in addition to the method of the second aspect, when determining the drive frequency, when the detected value of the drive voltage is less than the second set voltage, the auxiliary air The drive frequency is set to be larger than the drive frequency at the time of executing the auxiliary air control amount which is set in advance to execute the auxiliary air amount control by adjusting the opening degree of the control valve,
When the detected value of the drive voltage is equal to or higher than the second set voltage, the drive frequency is determined to be lower than the drive frequency when the auxiliary air control amount is executed.

According to FIG. 4, in the region above the driving frequency F2 (for example, 300 PPS) which is higher than the driving frequency FU when the auxiliary air control amount is executed, the driving voltage is lower than a certain voltage V2 (for example, 18 V). If so, the bounce-back phenomenon does not occur, which is probably because the resonance point was exceeded. On the other hand, when the drive voltage is equal to or higher than the voltage V2, it can be seen that the bounce-back phenomenon does not occur at the drive frequency F1 set to be smaller than the drive frequency FU when the auxiliary air control amount is executed. Therefore, the voltage V2 is determined as the second set voltage, the drive frequency when the detected value of the drive voltage is lower than the second set voltage V2 is defined as the drive frequency F2, and the detected value of the drive voltage is determined as the second set voltage. The drive frequency when the voltage is equal to or higher than the set voltage V2 is defined as the drive frequency F1, and the process according to the method of the present invention is executed, so that the step motor is operated at the optimum drive frequency, and the bounce-back phenomenon occurs. Can be prevented from occurring.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

FIGS. 1 to 7 show a first embodiment of the present invention. FIG. 1 is a schematic sectional view showing the structure of a throttle device, and FIG. 2 is a vertical sectional side view of an idle control valve and a step motor. 3 is a flowchart showing an initialization processing procedure, FIG. 4 is a graph showing a result of measuring the occurrence of a bounce-back phenomenon due to a drive voltage and a drive frequency,
FIG. 5 is a diagram showing changes in the step motor drive signal and the idle control valve operating position during the initialization process, FIG. 6 is a diagram sequentially showing the operating state of the idle control valve and the power transmission means from the fully closed position, and FIG. It is a figure which shows the change of the real position and target position of the idle control valve afterward.

First, in FIG. 1, a throttle body 2 is provided at an intermediate portion of an intake passage 1 connecting an air cleaner AC and an engine E. The throttle body 2 is provided with a throttle for adjusting an opening degree of the intake passage 1. The valve 3 is rotatably disposed, and a bypass passage 4 that bypasses the throttle valve 3 is provided. The bypass passage 4 is
An idle control valve V serving as an auxiliary air control valve for controlling the opening degree of the bypass passage 4 is provided in the throttle body 2 to control the idling rotational speed when the engine E is idling. You.

Referring also to FIG. 2, the idle control valve V
A valve seat 6 provided in the middle of the bypass passage 4 by forming a valve hole 5 connected to the upstream side 4a of the bypass passage 4, and a valve body 7 which can be seated on the valve seat 6 from the downstream side 4b of the bypass passage 4.
The valve element 7 is connected to a step motor M mounted on the throttle body 2 via power transmission means 8.

The stepping motor M is conventionally known, and its structure will not be described in detail. However, a slight gap is provided between the rotor 10 having the permanent magnet 9 on the outer peripheral surface and the outer peripheral surface of the rotor 10. And a pair of stators 11 and 12 that are fixedly arranged with a space therebetween and are adjacent in the axial direction. The two stators 11 and 12 are provided in common in a cylindrical mold part 13 made of a synthetic resin.
Is rotatably supported by the mold portion 13 via a ball bearing 14 so as to prevent movement in the axial direction.

The power transmission means 8 is formed by screwing a valve shaft 15 having one end fixed to the valve body 7 and a rotor 10 of a step motor M. That is, a male screw 16 provided on the valve shaft 15 is screwed into a screw hole 17 provided coaxially with the rotor 10, and a ridge 18 protruding along the axial direction on the outer surface of the valve shaft 15. Is the mold part 1
By being fitted into the guide groove 19 provided in the valve shaft 3, rotation of the valve shaft 15 around the axis is prevented. Therefore, the valve shaft 15 operates in the axial direction in accordance with the rotation of the step motor M, whereby the idle control valve V opens and closes. Moreover, the valve element 7 and the mold part 1
3, a coil-shaped return spring 20 is provided. The spring force of the return spring 20 causes the idle control valve V to move in the valve closing direction, that is, the direction in which the valve element 7 is seated on the valve seat 6. Will be energized.

Referring again to FIG. 1, the operation of the step motor M is controlled by a control unit C. This control unit C controls the operation of the step motor M by open loop control until the complete explosion of the engine. After the complete explosion of the engine, the operation of the step motor M is controlled by feedback control so as to reach the target engine speed corresponding to the engine cooling water temperature. Thus, in the open loop control up to the complete explosion of the engine, the control unit C
The opening position of the idle control valve V is previously associated with the number of operation pulses of the step motor M from the reference position, and the current position of the idle control valve V determined by the number of operation pulses of the step motor M from the reference position is determined. A pulse signal having a pulse number corresponding to the difference between the target position and the current position is output so as to match a target position predetermined as an opening required for starting according to the engine operating state (specifically, engine cooling water temperature). To control the operation of the step motor M.

Incidentally, the initialization process for associating the number of operation pulses of the step motor M with the opening position of the idle control valve V is executed, for example, immediately after the ignition switch is turned off, and the initialization process is performed. At this time, the control unit C controls the operation of the step motor according to the procedure shown in FIG.

In step S1 of FIG. 3, the number of repetitions N is set to "0". In step S2, it is checked whether the number of repetitions N is equal to or greater than the set number of "N0".
If it is NO, "1" is added to the number of repetitions N in step S3, and the number of operating pulses MP of the step motor M is subtracted by "1" in step S4, and the process returns to step S2.

The set number of times "N0" is set to a value equal to or more than the number of operating pulses of the step motor M for driving the idle control valve V from the fully open position to the fully closed position, and from step S1 to step S4. By processing up to
Regardless of the position immediately after the ignition switch is shut off, the idle control valve V is driven to the valve closing limit. That is, the idle control valve V is driven to the fully closed side until the valve element 7 is abutted against the valve seat 6.

When N ≧ N0 in step S2,
That is, when the idle control valve V has reached the fully closed position, the number of operation pulses MP of the step motor M is added by "1" in step S5, and in step S6, the number of operation pulses MP is equal to the predetermined number of pulses MP0. It is determined whether or not MP <MP0, and the process returns to step S5.

Here, the predetermined number of pulses MP0 is a value sufficient to drive the stepping motor M so that the rotor 10 in the power transmission means 8 can operate more than the backlash in the power transmission means 8. S5, S
By the process of No. 6, the idle control valve V is driven in the valve opening direction from the fully closed position to the set position.

In step S7 after the idle control valve V is opened to the set position in this way, the number M of operation pulses of the step motor M is reset in order to determine the set position as a reference position for idle speed control. I do.

In the next step S8, the number of operating pulses MP of the step motor M is added by "1". In step S9, it is determined whether or not the number of operating pulses MP has become equal to the predetermined number of pulses MP1, and MP < If it is MP1, the process returns to step S8.

Therefore, after the reset of the operation pulse number of the step motor M is completed, the step motor M is operated by the predetermined pulse number MP1, and the idle control valve V is driven from the reference position in the valve opening direction. In step S10, the power is turned off and the operation of the step motor M is stopped.

By the above-described processing in steps S1 to S4, the stepping motor M is set to its operating pulse number M
When operating until P reaches the set number of times "N0",
That is, when operating the idle control valve V to the valve closing limit, at least one of the drive frequency and the drive voltage of the step motor M is changed when the auxiliary air amount control is performed by adjusting the opening degree of the idle air control valve V, that is, when the idle air control is performed. Smaller than

As a result of the inventor's research on the bounce-back phenomenon, the natural frequency of the operating section including the rotor 10 of the step motor M, that is, the weight of the operating section, the frictional resistance when driving the idle control valve V, It has been found that the drive thrust of the step motor M, that is, the drive voltage, and the drive frequency that affects the resonance are factors that cause the bounce-back phenomenon. Although it cannot be changed, it can be changed, and by making at least one of the driving frequency and the driving voltage small, it is possible to prevent the bounce-back phenomenon from occurring.

On the other hand, when the present inventor measured the occurrence of the bounce-back phenomenon by changing the driving voltage and the driving frequency, the result shown in FIG. 4 was obtained. In FIG. 4, the drive frequency FU during normal idle control is relatively large in order to increase the control speed.
A value that is not too large such that a risk of step-out occurs when the battery voltage drops extremely, for example, 200 PPS
It has been found that a bounce-back phenomenon does not occur at a drive frequency lower than the drive frequency FU, for example, 100 PPS. Therefore, when operating the idle control valve V to the valve closing limit in order to perform the initialization process, the step motor M is operated at a drive frequency of 100 PPS which is a lower drive frequency than that in the normal idle control.

In the initialization processing immediately after the ignition switch is cut off, the operations of the step motor M and the idle control valve V are as shown in FIG. 5, and the valve is closed from time t ₁ when the ignition switch is turned off and the engine is stopped. by driving signal to the pulse number by the stepping motor M in the set direction number "N0" is given, the idle regulating valve V is certainly become fully closed even in any position when the ignition switch blocked at time t ₂ , then, by the step motor M by a predetermined number of pulses MP0 is actuated in the opening direction, when the idle regulating valve V is driven in the opening direction to a set position from the fully closed position at time t _3,
The number M of operation pulses of the step motor M is reset so as to determine the position as a reference position for the idle rotation speed control. Further, from time t ₃ , the step motor M is operated in the valve opening direction by a predetermined number of pulses MP1. When the idle control valve V is further operated from the reference position in the valve opening direction at time t ₄ , the step motor M Will stop operating.

Here, the operation of the idle control valve V from the fully closed position and the operation state of the power transmission means 8 at that time are as shown in FIG. 6, and the idle control shown in FIG. Even when the step motor M is operated by the amount including the backlash δ of the power transmission means 8 and the deviation of the excitation pattern of the step motor M from the time when the valve V is fully closed, as shown in FIG. The idle control valve V is in a fully closed state. Thereafter, when the step motor M is further operated to open the idle control valve V to a certain opening, the operation pulse of the step motor M is set as a reference position of the idle control valve V. The numbers will be reset.

Next, the operation of the first embodiment will be described. Immediately after the ignition switch is turned off, the idle control valve V is driven to the valve closing limit by the operation of the step motor M, and then the back-up by the power transmission means 8 is performed. More than rush rotor 1
0, the idle control valve V is driven from the fully closed position to the set position in the valve opening direction, and the number of operating pulses of the step motor M is reset to set the set position as a reference position for idle speed control. The step motor M is operated in the valve opening direction by a predetermined number of steps, and the idle control valve V is further opened from the reference position in the valve opening direction.

After resetting the number of operation pulses of the step motor M by such control processing, the operation of the step motor M to the target position and the actual operation of the idle control valve V accompanying the operation of the step motor M are performed. The operating position is shown in FIG.
It changes as shown by.

That is, after the initialization, the actual operation position of the idle control valve V is larger than the target position by the operation amount ΔA.
(The amount obtained by subtracting the backlash δ of the power transmission means 8 and the deviation of the excitation pattern in the step motor M from the total operation amount of the step motor M at the time of initialization), and delaying the operation of the step motor M to the target position. And the idle control valve V opens and closes. Therefore, when the engine is restarted, the responsiveness can be improved by quickly operating the idle control valve V to the target opening. Further, even in the fine adjustment near the fully closed position, the actual operating position does not differ between the valve opening drive and the valve closing drive of the idle control valve V, so that it is possible to accurately control the idle rotation speed, and the actual operating position.
Since it is the target position, it is possible to avoid the jerking of the engine rotation speed, to enable stable idle rotation speed control, and to eliminate the possibility of engine stall as much as possible.

Since the idle control valve V is slightly opened from the fully closed position when the ignition switch is shut off, there is no risk of icing, and the idle control valve V is further opened and held after initialization. Thus, the idle control valve V can be quickly operated up to the target opening when the engine is restarted, and the startability is further improved.

After the complete explosion of the engine, feedback control of the idle speed is performed so that the target engine speed corresponds to the temperature of the engine cooling water. Therefore, no problem occurs because the actual operating position is corrected.

Further, when the idle control valve V is driven to the valve closing limit, at least one of the drive frequency and the drive voltage of the step motor M is reduced, so that the bounce back phenomenon can be easily prevented.

Furthermore, since the driving frequency is reduced among the driving frequency and the driving voltage, the driving voltage can be kept at a relatively high value, and the opening of the idle control valve V and the step motor There is no possibility that a step-out occurs in correspondence with the number of operation pulses of.

FIG. 8 shows a first modification of the first embodiment. When the idle control valve V is driven to the valve closing limit, the drive frequency of the step motor M is changed to the drive frequency FU during idle control. And the driving voltage is forcibly reduced to a battery voltage of 12 V by a regulator (not shown).

This makes it possible to more reliably prevent the bounce-back phenomenon from occurring. At this time, by setting the lower limit of the drive voltage to the battery voltage, there is no possibility that the step-out occurs.

FIG. 9 shows a second modification of the first embodiment. When the idle control valve V is driven to the valve closing limit, the drive voltage of the step motor M is not changed and the drive voltage is not changed. The voltage is forcibly reduced to a battery voltage of 12 V by a regulator (not shown).

In this manner, the bounce-back phenomenon can be prevented from occurring while the control speed is kept high since the driving frequency can be kept high.

FIGS. 10 and 11 show a second embodiment of the present invention. FIG. 10 is a flowchart showing a control procedure for driving the idle control valve to the valve closing limit.
FIG. 6 is a diagram showing a step motor drive signal, an idle control valve operating position, and a change in drive voltage during an initialization process.

First, referring to FIG.
In step S12, the drive voltage V supplied to the step motor M is detected immediately before the step motor M is driven to one of the valve closing limit and the valve opening limit. In step S12, the detected drive voltage V is set to the first setting. It is determined whether or not the driving voltage V is equal to or lower than the voltage V1. If the detected driving voltage V is equal to or lower than the first set voltage V1 (V ≦ V1), the driving frequency is determined to be equal to the driving frequency FU during idle control in step S13. Drive voltage V exceeds the first set voltage V1 (V> V
If 1), in step S14, the drive frequency is set to a drive frequency F1 smaller than the drive frequency FU during idle control.

In step S15, the step motor M is driven at the drive frequency determined in step S13 or S14 by the set number of pulses "N0" or the set time corresponding to the determined drive frequency.

In FIG. 4, when the drive voltage exceeds a certain voltage V1 (for example, 14 V), a bounce-back phenomenon occurs at a drive frequency F1 set to be smaller than the drive frequency FU during idle control, for example, 100 PPS. When the driving voltage is equal to or lower than a certain voltage V1, the bounce-back phenomenon does not occur even at a driving frequency equal to the driving frequency FU during normal idle control. Therefore, the voltage V1 is defined as the first set voltage, and the drive frequency when the detected drive voltage V exceeds the first set voltage V1 is set as the drive frequency F1 smaller than the drive frequency during idle control. This makes it possible to prevent the bounce-back phenomenon from occurring by operating the stepping motor M at the optimum driving frequency.

At the time of such initialization processing, the step motor drive signal and the idle control valve operating position when the detected drive voltage V is equal to or lower than the first set voltage V1 are the same as those in FIG. Drive voltage V
FIG. 11 shows changes in the step motor drive signal, the idle control valve operating position, and the drive voltage when the voltage exceeds the first set voltage V1.

FIGS. 12 and 13 show a third embodiment of the present invention. FIG. 12 is a flowchart showing a control procedure for driving the idle control valve to the valve closing limit.
3 is a step motor drive signal at the time of initialization processing,
It is a figure which shows the change of an idle control valve operation position and a drive voltage.

First, in FIG. 12, step S21
In step S22, the drive voltage V supplied to the step motor M is detected immediately before the step motor M is moved to the valve closing limit. In step S22, it is determined whether the detected drive voltage V is lower than the second set voltage V2. If the detected drive voltage V is lower than the second set voltage V2 (V <V2), the drive frequency is set to a drive frequency F2 higher than the drive frequency FU during idle control in step S23.
If the detected drive voltage V is equal to or higher than the second set voltage V2 (V ≧ V
If 2), in step S24, the drive frequency is determined to be equal to the drive frequency F1 smaller than the drive frequency FU during idle control.

In step S25, the step motor M is driven at the drive frequency determined in step S23 or S24 by the number of pulses or the set time of the set number "N0" corresponding to the determined drive frequency.

Meanwhile, in FIG. 4 described above, in the region above the drive frequency F2 (for example, 300 PPS) which is higher than the drive frequency FU during normal idle control, the drive voltage is lower than a certain voltage V2 (for example, 18 V). if there is,
It seems that the bounce-back phenomenon did not occur, but the bounce-back phenomenon did not occur. When the drive voltage exceeded a certain voltage V2, the bounce-back phenomenon occurred at the drive frequency F1 which was set lower than the drive frequency FU during idle control. It turns out there is no. Therefore, the voltage V2 is defined as the second set voltage, and the drive frequency when the detected drive voltage V is lower than the second set voltage V2 is defined as the drive frequency F2, and the detected drive voltage V is determined as the second set voltage V2. By defining the drive frequency when the above is the drive frequency F1,
By operating the stepping motor M at the optimum driving frequency, it is possible to prevent the bounce back phenomenon from occurring.

At the time of such initialization, the step motor drive signal and the idle control valve operating position when the detected drive voltage V is equal to or higher than the second set voltage V1 are the same as those in FIG. Drive voltage V
Are smaller than the second set voltage V1, the changes in the step motor drive signal, the idle control valve operating position and the drive voltage are as shown in FIG.

In the third embodiment, when the detected drive voltage V is lower than the second set voltage V1, the drive frequency is increased to F2 and the drive voltage is decreased to 12V. Is also good.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

For example, in the above-described embodiment, the case where the initialization process is performed immediately after the ignition switch is turned off has been described. However, the timing of executing the initialization process is not limited to immediately after the ignition switch is turned off.
The initialization process can be performed immediately after the engine is stopped, after the engine is started, or while the vehicle is running.

In the above embodiment, the drive frequency FU during idle control is 200 PPS, and the drive frequency F1 is 100 PPS.
The PPS, the driving frequency F2 is 300 PPS, the first setting voltage V1 is 14 V, and the second setting voltage is 18 V. However, the driving frequency, the setting idle control valve V, and the type and weight of the step motor M may be appropriately changed. It is possible.

Further, the present invention can be applied to a device in which the idle control valve V is driven to abut in the valve opening direction during the initialization process.

[0062]

As described above, according to the first aspect of the invention, when the idle control valve is driven to one of the valve closing limit and the valve opening limit, at least one of the drive voltage and the drive frequency of the step motor is used. Can be reduced to prevent the bounce-back phenomenon from occurring.

According to the second aspect of the present invention, the optimum drive frequency is determined according to the drive voltage detected immediately before the step motor is driven to one of the valve closing limit and the valve opening limit, and the bounce back phenomenon occurs. Can be prevented.

According to the third or fourth aspect of the present invention, it is possible to prevent the bounce back phenomenon from occurring by operating the stepping motor at the optimum driving frequency.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing the configuration of a throttle device.

FIG. 2 is a vertical sectional side view of an idle control valve and a step motor.

FIG. 3 is a flowchart illustrating an initialization processing procedure.

FIG. 4 is a graph showing a result of measuring occurrence of a bounce-back phenomenon according to a driving voltage and a driving frequency.

FIG. 5 is a diagram illustrating changes in a step motor drive signal and an idle control valve operating position during an initialization process.

FIG. 6 is a diagram sequentially showing the operation states of the idle control valve and the power transmission means from the fully closed position.

FIG. 7 is a diagram showing changes in the actual position and the target position of the idle control valve after initialization.

FIG. 8 is a diagram illustrating changes in a step motor drive signal, an idle control valve operating position, and a drive voltage during an initialization process according to a first modified example.

FIG. 9 is a diagram illustrating changes in a step motor drive signal, an idle control valve operating position, and a drive voltage during an initialization process according to a second modified example.

FIG. 10 is a flowchart showing a control procedure when the idle control valve is driven to a valve closing limit in the second embodiment.

FIG. 11 is a diagram illustrating changes in a step motor drive signal, an idle control valve operating position, and a drive voltage during an initialization process.

FIG. 12 is a flowchart illustrating a control procedure when the idle control valve is driven to the valve closing limit in the third embodiment.

FIG. 13 is a diagram illustrating changes in a step motor drive signal, an idle control valve operating position, and a drive voltage during an initialization process.

[Explanation of symbols]

 4 ... Bypass passage M ... Step motor V ... Idle control valve as auxiliary air control valve

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kennosuke Narita 1-4-1 Chuo, Wako-shi, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Inventor Atsuhiko Sakamoto 1-4-chuo Chuo, Wako-shi, Saitama No. 1 Inside Honda R & D Co., Ltd. (72) Inventor Toshio Abe 1-4-1 Chuo, Wako-shi, Saitama Pref. Inside Honda R & D Co., Ltd. (72) Inventor Shigeru Inoue 1-4-4 Chuo, Wako-shi, Saitama Pref. No. 1 Inside Honda R & D Co., Ltd. (72) Inventor Takashi Sato Inside Honda R & D Co., Ltd.

Claims (4)

[Claims] 1. The number of operating pulses of a step motor (M) connected to an auxiliary air control valve (V) for adjusting an opening of a bypass passage (4) bypassing a throttle valve (V); In performing the initialization processing for associating the opening position of the valve (V) with the opening position, the step motor (M) is operated so as to drive the auxiliary air control valve (V) to one of the valve closing limit and the valve opening limit. In the stepping motor control method for the auxiliary air control valve, the driving frequency of the step motor (M) is controlled to drive the auxiliary air control valve (V) to either the valve closing limit or the valve opening limit during the execution of the initialization processing. And adjusting at least one of the driving voltage and the driving voltage to be smaller than when executing the auxiliary air amount control by adjusting the opening of the auxiliary air control valve (V). Valve step motor control method. 2. The number of operating pulses of a step motor (M) connected to an auxiliary air control valve (V) for adjusting an opening of a bypass passage (4) bypassing a throttle valve (V); In performing the initialization processing for associating the opening position of the valve (V) with the opening position, the step motor (M) is operated so as to drive the auxiliary air control valve (V) to one of the valve closing limit and the valve opening limit. In the stepping motor control method for the auxiliary air control valve, the step motor (M) is operated so as to drive the auxiliary air control valve (V) to one of the valve closing limit and the valve opening limit during the execution of the initialization processing. Immediately before, the drive frequency is determined based on the detected value of the drive voltage supplied to the step motor (M), and the step motor (M) is operated at the determined drive frequency. A step motor control method for an auxiliary air control valve, wherein the auxiliary air control valve (V) is driven to at least one of the valve closing limit and the valve opening limit. 3. The method according to claim 1, wherein when the detected drive voltage exceeds the first set voltage, the drive frequency is determined in advance to control the amount of auxiliary air by adjusting the opening of the auxiliary air control valve (V). The driving frequency is determined to be smaller than the driving frequency when the auxiliary air control amount is executed, and when the detected value of the driving voltage is equal to or lower than the first set voltage, the driving frequency is set to a value equal to the driving frequency when the auxiliary air amount control is executed. 3. The step motor control method for an auxiliary air regulating valve according to claim 2, wherein: 4. When determining the drive frequency, when the detected value of the drive voltage is less than the second set voltage, the control of the auxiliary air amount by adjusting the opening of the auxiliary air control valve (V) is performed in advance. The driving frequency is set to be higher than the driving frequency at the time of executing the set auxiliary air control amount, and when the detected value of the driving voltage is equal to or higher than the second set voltage, the driving frequency is set lower than the driving frequency at the time of executing the auxiliary air control amount. The method according to claim 2, wherein the frequency is determined.