JPH0610729A - Start-up time control device for internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent the non-conformity of start-up with a lowering of the battery voltage at the time of current-carrying to a throttle motor by multiplying each value from a current-carrying time map and a battery voltage map to compute a new current-carrying time and correct the battery voltage. CONSTITUTION:In a start-up time control device 2, opening and closing of an intake throttle valve 4 is driven by a throttle motor 12 at the idle operation time of an internal combustion engine to change the throttle open degree for control. An idle switch 14 and a control means 16 are connected to the throttle motor 12. A throttle open degree sensor 18 and a battery 20 are connected to the control means 16. In this case, a current-carrying time map of the throttle motor 12 and the voltage map of the battery 20 are provided in the control means 16. At the time of current-carrying to the throttle motor 12, each value from both the maps is multiplied together to compute a new current-carrying time, and the voltage of the battery 20 is corrected to control the drive of the throttle motor 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a start-up control device for an internal combustion engine, and more particularly, when energizing a throttle motor,
The present invention relates to a start-up control device for an internal combustion engine that corrects a battery voltage based on a calculated correction value.

[0002]

2. Description of the Related Art In an intake system for introducing intake air into an internal combustion engine, a step in which the intake throttle valve is driven by energization / de-energization to force the intake throttle valve to open / close to change the throttle opening when the engine is idle. Some are equipped with an idle speed control device having a throttle motor (DC motor) which is a motor. In the idle speed control device, the throttle opening is adjusted by the expansion and contraction of the plunger of the throttle motor during idle operation. The movement of the throttle motor is controlled by the control means (ECU).

Further, an idle switch for turning on and off is provided on the tip end side of the throttle motor to detect idle operation of the internal combustion engine. Further, the throttle opening during idle operation is input to the control means from a throttle opening sensor provided on the opposite side of the throttle lever. The throttle motor is controlled only when the idle switch is turned on.

The control of the throttle motor, that is, the energization of the throttle motor and the target full-closed opening control are performed by the target throttle opening and the actual throttle opening at the time of starting or during deceleration when the idle switch is on and the ISC control is not performed. And the difference ΔVTA (ITDC
MTA, see FIG. 4).

As a condition for prohibiting energization of the throttle motor, for example, once energizing the throttle motor, energizing is not performed for 100 ms thereafter (referred to as "energization OFF time").

Further, such an idle speed control device is disclosed in, for example, Japanese Patent Application Laid-Open No. 56-20730. In the device described in this publication, at least one of the pulse width and drive voltage, which is the basis of DC motor drive, is set independently for forward rotation and reverse rotation of the DC motor, and D
The idle speed of the engine is corrected and controlled toward the target speed without being affected by the drive characteristics of the C motor and the acceleration / deceleration characteristics of the engine.

[0007]

However, in the conventional start-up control device for an internal combustion engine, the target full-closed opening control is performed so that the throttle opening is predetermined at the start. The battery voltage may drop at the time of starting as described above.

This decrease in the battery voltage causes a difference between the energization time to the throttle motor and the operation amount of the throttle motor, and this difference slows the operation of the throttle motor.

As a result, the ITD is determined according to the difference ΔVTA between the target throttle opening and the actual throttle opening.
The intake throttle valve is not opened / closed at a speed corresponding to the energization time of the CMTA table, the throttle opening is insufficient at the time of starting, and the engine speed does not rise to a predetermined speed, which may cause a start failure. There is an inconvenience of being disadvantageous in practical use.

[0010]

In order to eliminate the above-mentioned inconvenience, the present invention is driven by energization / de-energization to open / close the intake throttle valve and change the throttle opening during idle operation of the internal combustion engine. In an internal-combustion-engine start-up control device having a throttle motor, a conduction time map for determining a conduction time of the throttle motor is provided, a battery voltage map for determining a battery voltage correction constant from a battery voltage is provided, and the intake throttle valve is provided. When the throttle motor is energized to obtain the target throttle opening, a new energization time is calculated by multiplying the value from the energization time map and the battery voltage correction constant from the battery voltage map to calculate the new energization. Control means for correcting the battery voltage according to time to control the throttle motor to operate Characterized by providing.

[0011]

According to the invention as described above, when the throttle motor is energized in order to bring the intake throttle valve to the target throttle opening, the control means sets the value from the energization time map and the battery voltage correction constant from the battery voltage map. The new energization time is calculated by multiplying by and the battery voltage is corrected based on the calculated new energization time, and the throttle motor is controlled to operate. Is corrected to prevent a start failure due to a slowed operation of the throttle motor.

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 3 show an embodiment of the present invention. In FIG. 2, reference numeral 2 is a start-up control device for an internal combustion engine (not shown), and 4 is an intake throttle valve that controls the amount of intake air to the internal combustion engine 2. The intake throttle valve 4 includes a throttle valve shaft 6
Held in.

A semi-circular throttle lever 8 is connected to one end of the intake throttle valve 4. An accelerator wire 10 connected to an accelerator pedal (not shown) is connected to one end of the throttle lever 8.

At the other end of the throttle lever 8, a throttle motor 12 including a step motor (DC motor) is provided.
Is provided. The throttle motor 12 is equipped with an idle switch 14 that is in contact with the other end of the throttle lever 8 at its tip end side.

The idle switch 14 is used for the internal combustion engine 2
The throttle motor 12 turns on during idle operation of the
The control is performed so that it is turned off at times other than the idle operation.

A control means 16 (ECU) is connected to the throttle motor 12. Further, a throttle opening sensor 18 provided on the other end side of the throttle valve shaft 6 is connected to the control means 16. A battery 20 is connected to the throttle opening sensor 18.

An energization time map (IT) for determining the energization time (TDCMVTA) of the throttle motor 12
DCMVTA), and a battery voltage map (TKTDCM) for determining a battery voltage correction constant (KTDCM) from the battery voltage (BV), and the throttle motor 12 to set the intake throttle valve 4 to a target throttle opening.
When energizing, the energization time map (ITDCMV
TA) which is a value of energization time (TDCMVTA) and a battery voltage map, for example, a primary map of the battery voltage (T
Battery voltage correction constant (KTDC) from KTDC
M) and new energization time (TDCMVTA
1) is calculated and this new energization time (TDCMVTA1)
The control means 16 for correcting the battery voltage (BV) and controlling the throttle motor 12 to operate.
Is provided.

More specifically, the program of the control means 16 includes the energization time map (IT) of the throttle motor 12.
DCMVTA) and battery voltage primary map (TKTD)
CM) and are incorporated.

Then, the control means 16 controls the energization time (TDCMVTA) from the energization time map (ITDCMVTA).
TA) and the battery voltage correction constant (KT) according to the battery voltage from the primary map of the battery voltage (TKTDCM)
DCM) with the formula TDCMVTA1 = TDCMVTA × KTDCM to obtain a new energization time (TDCMVTA
1) is calculated.

In addition, the calculated new energization time (TDC
The battery voltage (BV) is corrected by the MVTA 1) and the throttle motor 12 is controlled to operate.

In this embodiment, the condition for prohibiting the energization of the throttle motor 12 is set so that, for example, after energizing the throttle motor 12, energizing is not performed for 100 ms thereafter.

Next, the operation will be described with reference to the flowchart of FIG.

When the program of the control means 16 is started (step 102), first, it is judged whether the internal combustion engine 2 is started or after it is started (step 10).
4).

Then, in the judgment of this step 104, if it is after the start, the program is moved to the end (step 112), and if the judgment of step 104 is the start, whether the idle switch 14 is on or not. Whether or not it is determined (step 106).

When the determination in step 106 is NO, that is, when the idle switch 14 is off, the program is moved to the end (step 112), and conversely Y is returned.
ES, that is, when the idle switch 14 is on, the energization time (TDCMVTA) from the energization time map (ITDCMVTA) and the primary map (T
The battery voltage correction constant (KTDCM) corresponding to the battery voltage from (KTDCM) is multiplied by the equation TDCMVTA1 = TDCMVTA × KTDCM to obtain a new energization time (TDCMVTA).
1) is calculated, and the calculated new energization time (TDCMVT
The battery voltage (BV) is corrected by A1), and the throttle motor 12 is energized to operate.

After the energization, the energization to the throttle motor 12 is turned off only for 100 ms (step 108).

Then, again, it is judged whether the internal combustion engine 2 is started or after it is started (step 110). If it is judged in step 110 that the internal combustion engine 2 is not started yet, the program ends (step 112). If it is determined that the idle switch 14 is on (step 10)
Return to 6).

As a result, when the battery voltage drops at the time of starting, such as at an extremely low temperature, the battery voltage (BV) can be corrected by the correction function of the control means 16, and the throttle motor due to the battery voltage drop can be corrected. 12
It is possible to eliminate the difference between the energization time to the valve and the operation amount of the throttle motor 12, and prevent the operation of the throttle motor from being slowed.

Further, since the operation of the throttle motor 12 is not slowed down, the intake throttle valve 4 is surely opened / closed, and there is no fear that the throttle opening degree will be insufficient at the time of starting. It is possible to raise the temperature and improve the starting failure, which is practically advantageous.

Further, since it can be dealt with only by changing the program in the control means 16, there is no fear of complicating the structure, the manufacturing is easy as in the conventional one, and the cost is reduced. It can be maintained and is economically advantageous.

[0031]

As described in detail above, according to the present invention, a battery for determining a battery voltage correction constant from a battery voltage is provided by providing an energization time map for determining the energization time of the throttle motor of the internal combustion engine startup control device. A voltage map is provided, and when energizing the throttle motor to set the intake throttle valve to the target throttle opening, a new energization time is obtained by multiplying the value from the energization time map and the battery voltage correction constant from the battery voltage map. Since the control means for calculating and correcting the battery voltage by this new energization time to control the throttle motor to operate is provided, the battery voltage is corrected by the correction function of the control means when the battery voltage drops at the time of starting. You can
The difference between the energization time to the throttle motor and the operation amount of the throttle motor due to the decrease in the battery voltage can be eliminated, so that the operation of the throttle motor can be prevented from slowing down and the operation of the throttle motor does not slow down. As a result, the intake throttle valve is reliably opened / closed, there is no fear that the throttle opening will be insufficient at the time of starting, and the engine speed can be increased to a predetermined speed, which can improve the starting failure. It is practically advantageous.

[Brief description of drawings]

FIG. 1 is a flowchart of start-up control showing an embodiment of the present invention.

FIG. 2 is a system configuration diagram of a startup control device.

FIG. 3 is a primary map of battery voltage (TKTDCM).

FIG. 4 shows the conventional technique of the present invention according to a difference ΔVTA between a target throttle opening and an actual throttle opening at the time of starting control of a throttle motor or during deceleration when an idle switch is on and ISC control is not performed. It is a map (ITDCMTA) to be determined.

[Explanation of symbols]

 2 Start-up control device 4 Intake throttle valve 8 Throttle lever 10 Accelerator wire 12 Throttle motor 14 Idle switch 16 Control means 18 Throttle opening sensor 20 Battery

Claims (1)

[Claims] 1. An energization for changing the throttle opening by opening and closing an intake throttle valve during idling of an internal combustion engine.
In a start-up control device for an internal combustion engine having a throttle motor driven by non-energization, a conduction time map for determining a conduction time of the throttle motor is provided, and a battery voltage map for determining a battery voltage correction constant from a battery voltage is provided, When energizing the throttle motor to set the intake throttle valve to the target throttle opening, a new energization time is calculated by multiplying the value from the energization time map and the battery voltage correction constant from the battery voltage map. A startup control device for an internal combustion engine, comprising control means for correcting the battery voltage based on the new energization time and controlling the throttle motor to operate.