JP2842763B2 - Engine control throttle valve open / closed state detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine control throttle valve open / closed state detecting device for detecting whether or not a throttle valve of an engine is fully closed or almost fully closed by releasing an accelerator. More particularly, the present invention relates to an engine control throttle valve open / closed state detecting device which has improved reliability and reduced cost.

[0002]

2. Description of the Related Art As is well known, many engine control devices are provided with a throttle valve open / closed state detecting device for detecting whether or not a throttle valve of an engine is almost fully closed. Various engine controls are performed based on the detection results.

For example, Japanese Patent Publication No. 53-42854 discloses a fuel injection device that stops fuel supply when the throttle valve is closed and the engine speed is higher than a predetermined speed. ing. Also, Tokubiko 6
Japanese Patent Application Laid-Open No. 1-191818 discloses an engine speed control device that performs closed-loop control of the engine speed to a target speed when the throttle valve is closed and the engine speed is lower than a predetermined speed. I have.

In these conventional devices, the closed state of the throttle valve is detected by providing a throttle opening sensor that responds to opening and closing of the throttle valve, an idle switch that is turned on or off when the throttle is fully closed, and the like.

[0005]

As described above, the conventional engine control throttle valve open / closed state detecting device requires dedicated devices such as a throttle opening sensor and an idle switch, so that the entire device is expensive. Therefore, there is a problem that cost reduction cannot be realized.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has been made in consideration of an engine control using a speed-density type fuel injection device which determines a fuel injection amount based on an engine speed and an intake pipe pressure. In the throttle valve open / closed state detection device, the detection reliability is improved by detecting the open / closed state of the throttle valve based on a pressure sensor signal that detects the intake pipe pressure without using a throttle opening sensor or idle switch. It is another object of the present invention to provide an engine control throttle valve open / closed state detection device which realizes cost reduction.

[0007]

According to a first aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device for calculating an engine speed corresponding to an engine drive timing; Pressure detecting means for detecting the intake pipe pressure, and pressure value calculation for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is closed at least according to the engine speed. Means, parameter calculating means for calculating a parameter representing a relationship between the intake pipe pressure with respect to the first and second pressure values, and learning for storing, as a learning value, a representative value obtained by arithmetically processing the parameters in time series. Value calculation means,
Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the learned value and the first and second pressure values; And a throttle valve closed state detecting means for determining that the throttle valve is in the closed state when the relationship is small.

According to a second aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device according to the first aspect, wherein the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The value is a first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is a second pressure value, and the parameter calculating means calculates the second pressure value, the first pressure value, The learning value calculation means uses the ratio of the difference between the intake pipe pressure and the first pressure value to the difference
When the parameter is smaller than the learning value, the parameter is stored as the learning value, and when the parameter is equal to or larger than the learning value and smaller than the predetermined value, the learning value is gradually increased and stored. A value obtained by multiplying a difference between the pressure value and the first pressure value by a learning value and further adding the first pressure value is used as a pressure estimated value. When the value is smaller than the value obtained by adding the values, it is determined that the throttle valve is in the closed state.

According to a third aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting apparatus according to the first aspect, wherein the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. A first pressure value, a deviation between a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude and the first pressure value is a second pressure value, and the parameter calculating means sets a second pressure value. The ratio of the difference between the intake pipe pressure and the first pressure value to the pressure value is used as a parameter, and the learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value. When the learning value is smaller than the predetermined value, the learning value is gradually increased and stored, and the pressure estimation value calculation means multiplies the second pressure value by the learning value and further adds the first pressure value as a pressure estimation value. , Throttle valve closed state detection hand , When the intake pipe pressure is smaller than the value obtained by adding a predetermined value to the estimated pressure value is to determine the throttle valve is closed.

According to a fourth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detecting means for detecting, a bypass intake passage for bypassing a throttle valve in the intake pipe, bypass air flow rate calculating means for estimating and calculating a bypass air flow rate in the bypass intake passage, and a throttle according to at least an engine speed and a bypass air flow rate. Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the valve is closed;
Parameter calculation means for calculating a parameter representing the relationship of the intake pipe pressure to the second pressure value, and learning value calculation means for storing a representative value obtained by processing the parameters in time series as a learning value; Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the learned value and the first and second pressure values; And a throttle valve closed state detecting means for determining that the throttle valve is in the closed state when the relationship is small.

According to a fifth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detecting means for detecting, and at least a first pressure related to an intake pipe pressure when the throttle valve is in a closed state according to at least the engine speed.
Pressure value calculating means for calculating the second pressure value and a second pressure value; parameter calculating means for calculating a parameter representing a relationship between the first and second pressure values to the intake pipe pressure; Learning value calculating means for storing the obtained representative value as a learning value; atmospheric pressure detecting means for detecting atmospheric pressure; learning value initial value calculating means for calculating an initial value of the learning value based on atmospheric pressure; Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the pressure value and the first and second pressure values; A throttle valve closed state detecting means for determining that the throttle valve is closed when the relationship is small.

According to a sixth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detecting means to detect, at least according to the engine speed,
Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state; and a relationship between the first and second pressure values and the intake pipe pressure. Parameter calculation means for calculating parameters,
A learning value calculating means for storing a representative value obtained by performing time-series arithmetic processing on a parameter as a learning value, and a throttle valve being in a closed state when the parameter is small in a predetermined relationship with the learning value. And a throttle valve closed state detecting means for determining.

According to a seventh aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device according to the sixth aspect, wherein the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The value is a first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is a second pressure value, and the parameter calculating means calculates the second pressure value, the first pressure value, The learning value calculation means uses the ratio of the difference between the intake pipe pressure and the first pressure value to the difference
When the parameter is smaller than the learning value, the parameter is stored as the learning value, and when the parameter is equal to or larger than the learning value and smaller than the predetermined value, the learning value is gradually increased and stored. When the value is smaller than a value obtained by adding a predetermined value to the value, it is determined that the throttle valve is in the closed state.

According to another aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device for calculating an engine speed corresponding to a drive timing of an engine; Pressure detecting means to detect, at least according to the engine speed,
Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is closed, and filtering the first and second pressure values to obtain the first and second pressure values; And a filtered pressure value calculating means for calculating a filtered pressure value, a parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second filtered pressure values, and a time-series parameter Value calculating means for storing a representative value obtained by performing an arithmetic operation as a learning value, and a pressure in the intake pipe when the throttle valve is closed based on the learning value and the first and second pressure values. Pressure estimation value calculation means for calculating the estimated value; and throttle valve closed state detection means for determining that the throttle valve is closed when the intake pipe pressure is smaller than the pressure estimation value in a predetermined relationship. Things.

According to a ninth aspect of the present invention, in the engine control throttle valve opening / closing state detecting apparatus according to the eighth aspect, the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The first pressure value is used as the first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is used as the second pressure value, and the post-filter pressure value calculating means converts the first and second pressure values into the first and second pressure values. On the other hand, a primary low-pass filtering process is performed to obtain first and second filtered pressure values, and the parameter calculating means calculates an intake pipe pressure with respect to a difference between the second filtered pressure value and the first filtered pressure value. And a ratio of a difference between the pressure value and the first filtered pressure value as a parameter.
When the parameter is smaller than the learning value, the parameter is stored as the learning value, and when the parameter is equal to or larger than the learning value and smaller than the predetermined value, the learning value is gradually increased and stored. A value obtained by multiplying a difference between the pressure value and the first pressure value by a learning value and further adding the first pressure value is used as a pressure estimated value. When the value is smaller than the value obtained by adding the values, it is determined that the throttle valve is in the closed state.

According to a tenth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detection means for detecting, pressure value calculation means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is closed at least according to the engine speed, The first pressure value is filtered to calculate the first filtered pressure value only when it is determined that the intake pipe pressure in the closed state of the throttle valve is in the increasing direction based on the first pressure value. Only when it is determined that the intake pipe pressure in the closed state of the throttle valve is in the increasing direction based on the first filtered pressure value calculating means and the second pressure value,
A second filtered pressure value calculating means for filtering the second pressure value to calculate a second filtered pressure value;
And parameter calculating means for calculating a parameter representing a relationship between the intake pipe pressure and the second filtered pressure value,
Learning value calculating means for storing, as a learning value, a representative value obtained by performing time-series arithmetic processing on the parameter;
Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the second pressure value and the second pressure value, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. And a throttle valve closed state detecting means for determining that the throttle valve is closed.

According to a thirteenth aspect of the present invention, in the engine control throttle valve opening / closing state detecting apparatus according to the tenth aspect, the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The first pressure value is a first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is a second pressure value, and the first post-filter pressure value calculation means determines that the first pressure value is Only when the pressure value is larger than the first filtered pressure value, the first pressure value is subjected to a first-order low-pass filtering process to obtain a first filtered pressure value. Only when the second pressure value is larger than the second post-filter pressure value, the second pressure value is subjected to a first-order low-pass filtering process to obtain a second post-filter pressure value. Pressure value after second filter and first filter The ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the pressure value and the first filtered pressure value is used as a parameter, and the learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value. Is larger than the learning value and smaller than the predetermined value, the learning value is gradually increased and stored, and the pressure estimation value calculating means multiplies the difference between the second pressure value and the first pressure value by the learning value. The value obtained by adding the first pressure value is regarded as a pressure estimated value, and the throttle valve closed state detecting means determines that the throttle valve is in a closed state when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimated value. It is determined.

According to a twelfth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detection means for detecting, pressure value calculation means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is closed at least according to the engine speed, Parameter calculation means for calculating a parameter representing the relationship of the intake pipe pressure to the first and second pressure values, and learning value calculation means for storing, as a learning value, a representative value obtained by processing the parameters in time series. Pressure estimation value calculating means for calculating an intake pipe pressure estimation value when the throttle valve is in a closed state based on the learned value and the first and second pressure values; A filtered pressure estimated value calculating means for performing a filtering process on the pressure estimated value to calculate a filtered pressure estimated value only when it is determined that the pressure estimated value is in a decreasing direction based on the intake pipe pressure; A throttle valve closed state detecting means for determining that the throttle valve is closed when the post pressure estimated value is smaller in a predetermined relationship.

An engine control throttle valve open / closed state detecting device according to a thirteenth aspect of the present invention comprises: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detection means for detecting, pressure value calculation means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is closed at least according to the engine speed, Parameter calculation means for calculating a parameter representing the relationship between the first and second pressure values and the intake pipe pressure; rotation speed change detection means for detecting that the change in engine speed is greater than or equal to a predetermined value; Means for operating for a predetermined period of time after the means detects a change in the engine speed, and parameters in time series when the timer means is not operating. A learning value calculating means for storing a representative value obtained by the processing as a learning value; and a pressure estimation value for the intake pipe when the throttle valve is closed based on the learning value and the first and second pressure values. Pressure estimation value calculating means for calculating;
A throttle valve closing state detecting means for determining that the throttle valve is in a closed state when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship.

According to a thirteenth aspect of the present invention, in the thirteenth aspect, the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The value is a first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is a second pressure value, and the parameter calculating means calculates the second pressure value, the first pressure value, The learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value, and uses the ratio of the difference between the intake pipe pressure and the first pressure value with respect to the difference as a parameter. And when the learning value is smaller than the predetermined value, the learning value is gradually increased and stored, and the pressure estimation value calculating means multiplies the difference between the second pressure value and the first pressure value by the learning value, and further calculates the first pressure value. The value obtained by adding Liters valve closed state detection means, when the intake pipe pressure is smaller than the value obtained by adding a predetermined value to the estimated pressure value is to determine the throttle valve is closed.

According to a fifteenth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; Pressure detecting means for detecting, a bypass intake passage for bypassing a throttle valve in the intake pipe, bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage,
Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve is closed according to at least the engine speed and the bypass air flow rate; and the first and second pressure values Parameter calculation means for calculating a parameter representing the relationship of the intake pipe pressure with respect to air flow, air flow change detection means for detecting that the change in bypass air flow is equal to or greater than a predetermined value, and air flow change detection means for detecting a change in bypass air flow. Timer means that operates for a predetermined period of time after the detection, and learning value calculation means that stores, as a learning value, a representative value obtained by calculating parameters in time series when the timer means is not operating; Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the pressure and the first and second pressure values; When small in a predetermined relationship to one in which the throttle valve and a throttle valve closed state detection means is determined to be a closed state.

According to a sixteenth aspect of the present invention, there is provided an engine control throttle valve open / closed state detecting device, comprising: an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; A pressure detecting means for detecting, a bypass intake passage for bypassing a throttle valve in the intake pipe, a bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage at least according to the presence or absence of an air conditioner load, and at least an engine speed Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve is in a closed state according to the bypass air flow rate, and the intake pipe pressure for the first and second pressure values Parameter calculating means for calculating a parameter representing the relationship of Learning value calculating means for storing a representative value as a learning value; timer means for operating for a predetermined period after the air conditioner load has changed from off to on; and updating of the learning value during the operation of the timer means. A bypass air flow rate correction means for correcting the bypass air flow rate so as to match the learned value; and a pressure estimated value of the intake pipe when the throttle valve is closed based on the learned value and the first and second pressure values. And a throttle valve closed state detecting means for determining that the throttle valve is closed when the intake pipe pressure is smaller than the pressure estimated value in a predetermined relationship. .

According to a seventeenth aspect of the present invention, in the engine control throttle valve opening / closing state detecting device according to the sixteenth aspect, the pressure value calculating means corresponds to the intake pipe pressure when the throttle valve is closed at a high altitude. The value is a first pressure value, the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is a second pressure value, and the parameter calculating means calculates the second pressure value, the first pressure value, The learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value, and uses the ratio of the difference between the intake pipe pressure and the first pressure value with respect to the difference as a parameter. When the value is smaller than the predetermined value, the learning value is gradually increased and stored, and when the parameter is smaller than the learning value, the bypass air flow correction means corrects the bypass air flow so that the parameter matches the learning value. When the parameter is greater than or equal to the learning value and smaller than the predetermined value, the bypass air flow rate is gradually increased, and the pressure estimation value calculating means multiplies the difference between the second pressure value and the first pressure value by the learning value, The value obtained by adding the first pressure value is regarded as a pressure estimated value, and the throttle valve closed state detecting means determines that the throttle valve is in a closed state when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimated value. It is determined.

[0024]

According to the first aspect of the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated. Is calculated based on the learning value and the first and second pressure values. An estimated value of the intake pipe pressure when the throttle valve is closed is calculated, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship, it is determined that the throttle valve of the engine is closed.

According to a second aspect of the present invention, a value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is set as the first pressure value, and a value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. Is the second pressure value, and the ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is a parameter. When the parameter is smaller than the learning value, When the parameter is a learning value, the learning value is gradually increased when the parameter is equal to or larger than the learning value and smaller than a predetermined value, and the difference between the second pressure value and the first pressure value is multiplied by the learning value to obtain a first value. The value obtained by adding the pressure value is used as the estimated pressure value. When the intake pipe pressure is smaller than the value obtained by adding the predetermined value to the estimated pressure value, it is determined that the throttle valve is in the closed state.

According to a third aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is set as the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. The difference between the first pressure value and the second pressure value is defined as a second pressure value.
The ratio of the difference between the intake pipe pressure and the first pressure value with respect to the pressure value is a parameter. When the parameter is smaller than the learning value, the parameter is set as the learning value. When the parameter is equal to or more than the learning value and smaller than the predetermined value, The learning value is gradually increased and the second
A value obtained by multiplying a difference between the pressure value of the first pressure value and the first pressure value by a learning value and further adding the first pressure value is used as a pressure estimated value, and the intake pipe pressure is calculated by adding a predetermined value to the pressure estimated value. Is smaller, it is determined that the throttle valve is closed.

According to a fourth aspect of the present invention, first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed and the bypass air flow rate. A parameter representing the relationship of the intake pipe pressure to the first and second pressure values is calculated, and the parameter is processed in time series to obtain a representative value, which is used as a learning value. The learning value and the first and second pressures are calculated. Calculates the estimated value of the intake pipe pressure when the throttle valve is closed based on the value and determines that the engine throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. Then, the open / close state of the throttle valve is accurately detected regardless of the presence or absence of the bypass air flow rate.

According to a fifth aspect of the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated.
And a parameter representing the relationship of the intake pipe pressure to the second pressure value is calculated, the parameters are processed in time series to obtain a representative value, which is used as a learning value, and an initial value of the learning value is calculated based on the atmospheric pressure. Calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the learned value and the first and second pressure values; It is determined that the throttle valve of the engine is in the closed state, and the open / closed state of the throttle valve is accurately detected immediately after the start of the engine regardless of the difference in the atmospheric pressure.

According to a sixth aspect of the present invention, first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated.
And a parameter representing the relationship of the intake pipe pressure to the second pressure value is calculated, and the parameter is calculated in a time series to obtain a representative value, which is used as a learning value. Sometimes, it is determined that the throttle valve of the engine is in the closed state, and the calculation of the estimated pressure value is omitted.

According to a seventh aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is set as the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. Is the second pressure value, and the ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is a parameter. When the parameter is smaller than the learning value, When the parameter is a learning value, the learning value is gradually increased when the parameter is equal to or larger than the learning value and smaller than a predetermined value, and when the parameter is smaller than a value obtained by adding the predetermined value to the learning value, the throttle valve is in a closed state. to decide.

According to the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated.
And the second pressure value is filtered to obtain the first and second pressure values.
Is calculated, a parameter representing the relationship of the intake pipe pressure with respect to the first and second filtered pressure values is calculated, and the parameter is calculated in a time series to obtain a representative value, which is used as a learning value. Calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the learning value and the first and second pressure values, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. Then, it is determined that the throttle valve is in the closed state, and erroneous learning value learning at the time of a sudden change in the engine state is prevented to accurately detect the throttle valve open / closed state.

According to a ninth aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is set as the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. Is a second pressure value, and the first and second pressure values are subjected to a first-order low-pass filter processing to obtain first and second filtered pressure values. The ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the filtered pressure value and the filtered pressure value is used as a parameter. When the parameter is smaller than the learned value, the parameter is used as a learned value.
When the parameter is greater than or equal to the learning value and smaller than the predetermined value, the learning value is gradually increased, and a value obtained by multiplying the difference between the second pressure value and the first pressure value by the learning value and further adding the first pressure value. Is the pressure estimated value, and when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimated value, it is determined that the throttle valve is in the closed state.

According to a tenth aspect of the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first pressure value is calculated. The first pressure value is filtered to calculate the first filtered pressure value only when it is determined that the intake pipe pressure in the closed state of the throttle valve is in the increasing direction based on the value, and the second filtered pressure value is calculated. Only when it is determined based on the pressure value that the intake pipe pressure when the throttle valve is in the closed state is in the increasing direction, the second pressure value is filtered and the second filtered pressure value is calculated. And a parameter representing the relationship of the intake pipe pressure to the second filtered pressure value is calculated, and the parameter is calculated in a time series to obtain a representative value, which is used as a learning value, and the learning value and the first and second pressures are calculated. The throttle valve is closed based on the value The estimated value of the intake pipe pressure at the time is calculated, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship, it is determined that the throttle valve is in the closed state. To prevent

In the eleventh aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. Is a second pressure value, and only when the first pressure value is greater than the first filtered pressure value, the first pressure value is subjected to the first low-pass filter processing to perform the first filtered pressure value. Only when the second pressure value is larger than the second filtered pressure value, the second pressure value is subjected to a primary low-pass filtering process to obtain a second filtered pressure value. The ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the filtered pressure value and the first filtered pressure value is a parameter, and when the parameter is smaller than the learning value, the parameter is set to the learning value. And the parameter is greater than or equal to the learning value and greater than the predetermined value. At this time, the learning value is gradually increased, and a value obtained by multiplying the difference between the second pressure value and the first pressure value by the learning value and further adding the first pressure value is used as a pressure estimation value. It is determined that the throttle valve is in the closed state when the value is smaller than the value obtained by adding the predetermined value to the estimated pressure value.

According to a twelfth aspect of the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated. A parameter representing the relationship of the intake pipe pressure to the pressure value of 2 is calculated, and the parameter is processed in time series to obtain a representative value, which is used as a learning value.
The pressure estimated value of the intake pipe when the throttle valve is in the closed state is calculated based on the pressure value and the pressure estimated value is calculated only when it is determined that the pressure estimated value is in the decreasing direction based on the pressure estimated value. Filter processing to calculate a filtered pressure estimated value.When the intake pipe pressure is smaller than the filtered pressure estimated value in a predetermined relationship, it is determined that the throttle valve is closed, and the throttle valve open / closed state is determined. Stable detection.

According to a thirteenth aspect of the present invention, the first and second pressure values related to the intake pipe pressure when the throttle valve is closed are calculated according to the engine speed, and the first and second pressure values are calculated. A parameter representing the relationship of the intake pipe pressure with respect to the pressure value is calculated, a change in the engine speed is detected to be greater than or equal to a predetermined value, and a timer means that operates for a predetermined period after detecting the change in the engine speed operates. When the throttle valve is closed, the representative value is obtained by performing time-series arithmetic processing on the parameter to obtain a learned value, and based on the learned value and the first and second pressure values, the intake pipe when the throttle valve is closed. The throttle valve is determined to be in a closed state when the intake pipe pressure is smaller than the pressure estimated value in a predetermined relationship. Check the valve open / close state To detect the probability.

According to a fourteenth aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at high altitude is set as the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at low altitude. Is the second pressure value, and the ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is a parameter. When the parameter is smaller than the learning value, The parameter is a learning value, and when the parameter is equal to or larger than the learning value and smaller than a predetermined value, the learning value is gradually increased.
A value obtained by multiplying a difference between the pressure value of the first pressure value and the first pressure value by a learning value and further adding the first pressure value is used as a pressure estimated value, and the intake pipe pressure is calculated by adding a predetermined value to the pressure estimated value. Is smaller, it is determined that the throttle valve is closed.

According to a fifteenth aspect of the present invention, the bypass air flow rate is estimated and calculated, and the first and second air flows related to the intake pipe pressure when the throttle valve is closed according to the engine speed and the bypass air flow rate. 2, a parameter representing the relationship between the first and second pressure values and the intake pipe pressure is calculated, and it is detected that the change in the bypass air flow rate is equal to or greater than a predetermined value, and the change in the bypass air flow rate is detected. Is detected, when the timer means that operates for a predetermined period of time is not operating, a parameter is calculated in a time series to obtain a representative value to obtain a learning value, and the learning value and the first and second pressure values are converted to the learning value. An estimated value of the intake pipe pressure when the throttle valve is closed is calculated based on the predetermined value, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship, it is determined that the throttle valve is closed, and the bypass air is determined. Regardless of the state of change of flow, accurately detecting a throttle valve opening and closing condition to prevent erroneous learning learning value at the engine state changes suddenly.

According to a sixteenth aspect of the present invention, a bypass air flow rate is estimated and calculated according to the presence or absence of an air conditioner load, and the intake pipe pressure when the throttle valve is closed according to the engine speed and the bypass air flow rate. The first and second pressure values related to the first and second pressure values are calculated, a parameter representing the relationship between the first and second pressure values and the intake pipe pressure is calculated, and the parameters are processed in time series to obtain a representative value. During the operation of the timer means which operates for a predetermined period after the air conditioner load changes from off to on, the update of the learning value is prohibited, and the bypass air flow rate is corrected so that the parameter matches the learning value. Calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the learned value and the first and second pressure values, and the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. Throttle valve can is determined to be closed, regardless of the differences in the bypass air flow rate to prevent the erroneous learning of the learning value, accurately detect the open or closed state of the throttle valve.

According to a seventeenth aspect of the present invention, the value corresponding to the intake pipe pressure when the throttle valve is fully closed at a high altitude is the first pressure value, and the value corresponding to the intake pipe pressure when the throttle valve is fully closed at a low altitude. Is the second pressure value, and the ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is a parameter. When the parameter is smaller than the learning value, When the parameter is a learning value, the learning value is gradually increased when the parameter is equal to or larger than the learning value and smaller than a predetermined value, and when the parameter is smaller than the learning value, the bypass air flow rate is corrected so that the parameter matches the learning value, When the parameter is equal to or more than the learning value and smaller than the predetermined value, the bypass air flow rate is gradually increased, and the difference between the second pressure value and the first pressure value is multiplied by the learning value, and the first pressure value is further added. Value as the pressure estimate, and Throttle valve is judged to be closed when the pipe pressure is less than the value obtained by adding a predetermined value to the estimated pressure.

[0041]

【Example】

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram schematically showing an overall configuration of a first embodiment (corresponding to claims 1 and 2) of the present invention.
Speed Density SPI (Single Point
This shows a case where the present invention is applied to an engine for fuel control by injection.

In FIG. 1, reference numeral 1 denotes a well-known spark-ignition engine mounted on, for example, an automobile, 2 denotes an air cleaner for purifying intake air, 3 denotes an intake pipe through which the intake air passes through the air cleaner 2, and 4 denotes intake air. The engine 1 is a throttle valve provided in the pipe 3 for adjusting the amount of intake air.
Combustion air is mainly sucked from the upstream side through the air cleaner 2, the intake pipe 3, and the throttle valve 4.

The intake pipe 3 includes, from the upstream side, an air intake 3a, a throttle body 3b whose opening cross-sectional area is adjusted by a throttle valve 4, and an intake manifold 3c.
It is composed of Reference numeral 5 denotes a water temperature sensor that detects the temperature of the cooling water (described later), and outputs a detection signal corresponding to the detected water temperature.

Reference numeral 6 denotes a bypass air passage provided to bypass the throttle valve 4 in the throttle body 3b, and an inlet and an outlet are provided upstream and downstream of the throttle valve 4 of the throttle body 3b. . 6
a is a first idle air passage (hereinafter abbreviated as FIA passage) 6 a provided in the bypass air passage 6.

Reference numeral 7 denotes a wax type first idle air valve (hereinafter referred to as FI) provided in the middle of the FIA passage 6a.
Reference numeral 8 denotes cooling water that covers the outer periphery of the engine 1. The FIA valve 7 automatically adjusts the cross-sectional area of the FIA passage 6a in accordance with the temperature of the cooling water 8, and controls a part of the bypass air flow rate.

Another inlet of the bypass air passage 6 is
Throttle body 3 further upstream than the other inlet
and a bypass passage 9 for an air conditioner and a bypass passage for idle speed control (hereinafter abbreviated as an ISC bypass passage) 10 which are located in parallel with each other and are connected in parallel with each other. Each bypass passage 9 and 10
Is located downstream of the FIA valve 7 in the FIA passage 6a.

Reference numeral 11 denotes an air conditioner idle up solenoid valve (hereinafter abbreviated as ACIUS valve) for controlling an opening cross-sectional area of the air conditioner bypass passage 9, and reference numeral 12 denotes an air conditioner switch operated by an occupant of an automobile. A
The CIUS valve 11 fully opens and closes in accordance with the on / off of the air conditioner switch 12, and controls a part of the bypass air flow rate. The bypass air flow rate when the ACIUS valve 11 is fully opened can be manually adjusted according to the load of the air conditioner.

Reference numeral 13 denotes an idle speed control solenoid valve (hereinafter abbreviated as an ISC solenoid valve) for controlling an opening cross-sectional area of the ISC bypass passage 10.
The opening degree is adjusted according to the duty ratio of the drive signal, and, for example, a part of the bypass air flow rate is controlled so that the engine speed during idling becomes the target speed.

With the above configuration, the opening cross-sectional area of the bypass air passage 6 (the effective cross-sectional area of the bypass air passage) is FIA.
Controlled by the valve 7, the ACIUS valve 11, and the ISC solenoid valve 13, the bypass air flow rate is controlled. The bypass air that has passed through the bypass air passage 6 is introduced into the engine 1 for combustion.

Reference numeral 14 denotes a pressure sensor provided with a pressure inlet further downstream than the outlet of the bypass air passage 6. The pressure sensor 14 detects the pressure (intake pipe pressure) Pb in the intake pipe 3 by an absolute value. A detection signal corresponding to the detected intake pipe pressure Pb is output. By detecting the intake pipe pressure Pb before the start of the engine 1, the pressure sensor 14 also functions as an atmospheric pressure sensor.

Reference numeral 15 denotes a single injector provided in the throttle body portion 3b further upstream than the inlet of the bypass air passage 6, which is connected to a fuel system (not shown), and is used for intake for combustion taken into the engine 1. Fuel corresponding to the amount of air is injected and supplied by opening the valve. The injected fuel is supplied to the engine 1 as a mixture with the intake air.

Reference numeral 16 denotes an ignition coil comprising a primary winding and a secondary winding, and 17 denotes an igniter connected to an ignition control system. The primary side of the ignition coil 16 is an igniter 17.
The high voltage generated from the secondary side is supplied to a spark plug (not shown) provided for each cylinder of the engine 1 to perform ignition. In this case, the output signal of the primary winding of the ignition coil 16 is also used as a rotation signal synchronized with the drive timing of the engine 1.

Reference numeral 18 denotes an exhaust pipe of the engine 1, and 19 denotes an exhaust gas purifying catalyst provided downstream of the exhaust pipe 18.
Exhaust gas from the engine 1 is supplied from an exhaust pipe 18 to a catalyst 19.
Through which harmful components are removed and at least a portion is released to the atmosphere.

20 is a microcomputer (to be described later)
The control device is configured to calculate an idle speed control amount, a fuel injection amount, and the like by predetermined arithmetic processing based on various switch signals, sensor signals, and the like, and to drive and control the ISC solenoid valve 13, the injector 15, and the like. .
Reference numeral 21 denotes a battery serving as a power supply power source for operating the control device 20, and reference numeral 22 denotes a key switch inserted between the battery 21 and the control device 20.

FIG. 2 is a block diagram showing a specific configuration of the control device 20 shown in FIG. 1. 100 is a microcomputer and 101 to 103 are first to third inputs for inputting various signals to the microcomputer 100. An interface circuit 104 is an output interface circuit for outputting a calculation result from the microcomputer 100 as a control signal, and 105 is a first power supply circuit for operating the microcomputer 100.

The first input interface circuit 101 receives a primary signal from the ignition coil 16, and the second input interface circuit 102 includes the water temperature sensor 5 and the pressure sensor 1.
4 and the third input interface circuit 103 receives the on / off signal of the air conditioner switch 12. Further, the output interface circuit 104
A control signal is output to the C solenoid valve 13 and the injector, and the first power supply circuit 105 is supplied with power from the battery 21 via the key switch 22.

The microcomputer 100 includes the following components 200 to 209. Reference numeral 200 denotes a CPU for performing various arithmetic processes and determinations; 201, a counter for measuring a rotation cycle of the engine 1; 202, a timer for measuring a drive time for control; 203, a second interface circuit 102; An A / D converter for converting an analog signal input through the third interface circuit 103 into a digital signal is an input port for transmitting the digital signal input through the third interface circuit 103 to the CPU 200.

A RAM 205 functions as a work memory of the CPU 200, a ROM 206 stores a main flow program (to be described later) for operating the CPU 200 and various maps, and an output 207 outputs a command signal of the CPU 200. A port 208 is a timer for measuring a duty ratio of a drive signal supplied to the ISC solenoid valve 13, and a reference numeral 209 is a common bus connecting the CPU 200 and various components 201 to 208.

In the first embodiment of the present invention, the control device 2
0 is an engine speed calculating means for calculating an engine speed Ne corresponding to the drive timing of the engine 1 from a primary signal of the ignition coil 16;
e, a pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure Pb when the throttle valve 4 in the intake pipe is closed, and for the first and second pressure values. Parameter calculation means for calculating a parameter KR representing the relationship of the intake pipe pressure Pb, learning value calculation means for storing a representative value obtained by performing a time-series calculation processing of the parameter KR as a learning value KL, and a learning value KL Pressure estimated value calculating means for calculating an estimated value PBC of the intake pipe when the throttle valve 4 is in the closed state, based on the pressure value and the first and second pressure values; And a throttle valve closed state detecting means for judging that the throttle valve is in the closed state when it is small in a predetermined relationship.

The pressure value calculating means sets a first pressure value PBH corresponding to the intake pipe pressure when the throttle valve is closed at high altitude, and a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude. PBL is set as a second pressure value, and the parameter calculating means calculates a ratio of a difference between the intake pipe pressure and the first pressure value to a difference between the second pressure value and the first pressure value as a parameter KR.
The learning value calculation means determines that the parameter KR is the learning value KL
When the parameter KR is smaller than the learning value KL, the learning value is gradually increased and stored when the parameter KR is equal to or larger than the learning value KL and smaller than a predetermined value (for example, 1.2).

The pressure estimation value calculating means multiplies the difference between the second pressure value and the first pressure value by a learning value KL,
The throttle valve closed state detecting means determines that the throttle valve is in a closed state when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. to decide.

Hereinafter, the general operation of the control device 20 will be described with reference to FIG. 1 and FIG. First, an ignition signal obtained from the primary side of the ignition coil 16 is subjected to waveform shaping or the like via a first input interface circuit 101, and becomes an interrupt command signal to become an interrupt command signal.
Input to 0.

Each time this interrupt is issued, the CPU 200 in the microcomputer 100
Is read and the engine 1 is calculated from the difference from the previous counter value.
And the rotation speed data Ne representing the engine rotation speed is calculated.

The analog signals from the water temperature sensor 5 and the pressure sensor 14 are supplied to the second input interface circuit 102.
, Noise components are removed or amplified, and
Via the / D converter 203, it is converted into digital data of an intake pipe pressure value Pb representing the intake pipe pressure and a cooling water temperature value WT representing the temperature of the cooling water 8. Here, the intake pipe pressure value Pb is proportional to the detected intake pipe pressure, and the cooling water temperature value WT is proportional to the detected cooling water temperature.

The on / off signal from the air conditioner switch 12 is converted to a digital signal level via the third input interface circuit 103 and then input to the input port 204.

CPU 2 in microcomputer 100
00 is, for example, 100 based on these input data.
The bypass air control amount is calculated every msec, and the driving time of the injector 15 is calculated. In addition, by synchronizing with the generation of the interrupt command signal, the time is measured by the timer 208 at a duty ratio corresponding to the bypass air control amount, and similarly, the time corresponding to the fuel injection amount is measured by the timer 202.

During the measurement by the timer 208 or 202, the CPU 200 outputs
A drive command is given to the output interface circuit 104. As a result, the output interface circuit 104
A drive signal having the above duty ratio is supplied to the SC solenoid valve 13 to control the opening of the ISC solenoid valve 13. Further, a drive signal is supplied to the injector 15, and the injector 15 is driven to open for the calculated drive time τ.

The first power supply circuit 105 includes the key switch 22
Is turned on, the voltage of the battery 21 is adjusted to a constant voltage and supplied to the microcomputer 100 to operate the microcomputer 100.

Next, a specific operation of the first embodiment of the present invention will be described with reference to the flowchart of FIG.

Referring to FIG. 3, first, when the power of the control device 20 is turned on by turning on the key switch 22, the CPU 200 in the microcomputer 100 starts operating. That is, in step S1, the start flag indicating that the initialization of the RAM 205 has been completed is reset to 0.

Then, the process proceeds to a step S2, where the actual rotation speed data Ne representing the engine rotation speed is obtained from the rotation period already detected by the ignition signal from the ignition coil 16, and is read. In step S3, the intake pipe pressure value Pb representing the intake pipe pressure detected by the pressure sensor 14 is read. Similarly, the process proceeds to step S4, in which a coolant temperature value W representing the coolant temperature detected by the coolant temperature sensor 5 is set.
Read T.

Then, the process proceeds to a step S5, wherein it is determined whether or not the start flag is 0.
If it is determined as ES), the process proceeds to step S6, where the intake pipe pressure value Pb is stored in the RAM 205 as the atmospheric pressure value Pa, and after the process of step S6 is completed, the process proceeds to step S7.
If it is determined in step S5 that the start flag is 1 (that is, NO), the process proceeds to step S7 without performing the process of step S6.

In step S7, the throttle valve 4
The open / closed state detection routine (detailed in FIG. 5) is executed, and if it is determined that the throttle valve 4 is closed, the valve closing flag is set to 1 and it is determined that the throttle valve 4 is not closed. In this case, the valve closing flag is reset to 0.

Subsequently, the process proceeds to step S8, where the RAM 20
The start flag is set to 1 to indicate that the initialization of 5 has been completed. Further, the process proceeds to step S9, and the processing of an idle speed control routine (details thereof are shown in FIG. 4) is executed.

Next, the routine proceeds to step S10, where it is determined whether or not the valve closing flag is 1, and the valve closing flag is set to 1 (ie, YES:
When it is determined that the throttle valve 4 is in the closed state, the process proceeds to step S11 and the engine speed Ne is set to 15
It is determined whether or not it is not less than 00 rpm. If Ne ≧ 150
If it is determined to be 0 rpm (that is, YES), it is determined that the engine 1 is in a decelerating state, and the process proceeds to step S12, where the drive time τ of the injector 15 is set to 0 to stop fuel injection.

On the other hand, in step S11, Ne <1
If it is determined to be 500 rpm (that is, NO), the process proceeds to step S13, and the drive time τ of the injector 15 during normal operation is obtained. If it is determined in step S10 that the valve closing flag = 0 (that is, NO), the process proceeds to step S13 without executing the determination step S11.

In step S13 for obtaining the drive time τ of the injector 15 during normal operation, first, a two-dimensional map is mapped from the engine speed Ne and the intake pipe pressure value Pb, and the volume efficiency CEV (Ne, Pb) is obtained. Obtained by calculation. Next, the routine proceeds to step S14, where the cooling water temperature value W
The one-dimensional map is mapped from T, and the warm-up increase coefficient CW
T (WT) is obtained by calculation.

Finally, the process proceeds to step S15, where the constant K,
Intake pipe pressure value Pb, volumetric efficiency CEV, and warm-up increase coefficient C
Using the WT, the driving time τ of the injector 15 is obtained according to the following equation.

Τ = K × Pb × CEV × CWT

After the processes in steps S15 and S12, the process returns to step S2 to repeat the above operation.

Next, the flowchart of FIG.
The specific processing of the idle speed control routine (step S9) in FIG. 3 will be described with reference to the explanatory diagram of FIG. First, in step S90, it is determined whether or not the valve closing flag is 1 (that is, the throttle valve 4 is closed). If the valve closing flag is 1 (that is, YES) and the throttle valve 4 is closed, Proceeding to step S91, it is determined whether or not the cooling water temperature value WT is equal to or higher than a value corresponding to 70 ° C. (the engine 1 is sufficiently warmed up).

If the cooling water temperature value WT is equal to or more than 70 ° C. (ie, YES) and the engine 1 is sufficiently warmed up, the process proceeds to step S92, and the air conditioner switch 12 is turned on (ie, the air conditioner It is determined whether or not this is the case.

If the air conditioner switch 12 is off (ie, NO), the process proceeds to step S93, where the target speed data Nt representing the target speed is set to a value corresponding to 800 rpm, and the air conditioner switch 12 is turned on (ie, NO). YE
If S), the process proceeds to step S94, where the target rotation speed data Nt is set to a value corresponding to 1000 rpm.

After the target rotation speed data Nt is set in step S93 or S94, the process proceeds to step S95,
It is determined whether the timing is every 100 msec. If the timing is not every 100 msec (ie, N
If it is determined to be O), the idle speed control routine of FIG. 4 is terminated and the process returns. If it is determined that the timing is every 100 msec (that is, YES), step S9 is performed.
Proceed to 6.

In step S96, a deviation ΔN between the target rotation speed data Nt and the actual rotation speed data Ne is obtained, and a control gain for converging the engine rotation speed to the target rotation speed by mapping a one-dimensional map of the deviation ΔN. Find KI. 1 for obtaining control gain KI from deviation ΔN
For example, a map as shown in FIG. 9 is used as the dimension map.

As shown in FIG. 9, the relationship between the deviation ΔN and the control gain KI is such that as the deviation ΔN increases or decreases from 0, the control gain KI shifts from 0 (dead band) to a proportional relationship, and the deviation ΔN Is further increased or decreased, the control gain KI is limited to prevent divergence.

Subsequently, in step S97, IS
ISC bypass passage 1 by C solenoid valve 13
Air flow rate QIS for ISC that is equivalent to target air flow rate of 0
The control gain KI calculated in step S96 is added to the previous value of C (the value before 100 msec) to update the ISC air flow rate QISC.

In step S98, according to the updated ISC air flow rate QISC, a driving signal for driving the ISC solenoid valve 13 to the target air flow rate by performing a mapping operation using a one-dimensional map. Find the duty ratio. As the one-dimensional map for obtaining the duty ratio, for example, a map as shown in FIG. 10 is used.

The drive signal at this time is as shown in FIG. 11, and the ISC solenoid valve 13 is turned on.
The time during the cycle is TON, and the time of one cycle is T
Then, the duty ratio is (TON / T) × 100
[%]. This duty ratio is proportional to the opening of the ISC solenoid valve 13.

On the other hand, in step S90, it is determined that the throttle valve 4 is not in the closed state (valve closing flag = 0), or in step S91, the engine is not sufficiently warmed up (cooling water temperature WT <70). If the value is determined to be (° C equivalent value), the process proceeds to step S99, and the ISC air flow rate value Q
The ISC is set to a predetermined value QOPEN for setting the target air flow rate during the open control.

After the ISC air flow rate value QISC has been set in this way, the flow proceeds to the duty ratio calculation step S98, and FIG.
Ends the idle speed control routine.

Next, a detailed processing operation of the throttle valve open / closed state detection routine (step S7) in FIG. 3 which is a feature of the first embodiment of the present invention will be described with reference to FIGS. I do.

FIG. 13 shows a lowland fully closed intake pressure value PBL (Ne) and a highland fully closed intake pressure value PBH (Ne) stored in correspondence with each engine speed Ne, and a reference for judging a throttle valve closed state. Predicted fully closed intake pressure PB calculated as
It is explanatory drawing which shows each characteristic with C. FIG. 14 is an explanatory diagram showing changes in the parameter KR and the learning value KL with respect to time changes in the atmospheric pressure Pa and the throttle opening θ.

Generally, in order to determine whether or not the throttle valve 4 is closed based on the intake pipe pressure, the intake pipe pressure when the throttle valve 4 is closed (hereinafter referred to as the fully closed intake pipe pressure). If the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the throttle valve, the throttle valve 4 may be determined to be in the closed state.

However, the pressure of the fully-closed intake pipe changes depending on the atmospheric pressure, the flow rate of the bypass air, and the like, and also slightly changes depending on variations in the engine 1 and the state of adjustment. Therefore, it is necessary to predict the atmospheric pressure at that time, the bypass air flow rate, or the fully closed intake pressure according to the state of the engine 1.

Therefore, in the first embodiment of the present invention,
An example will be described in which the atmospheric pressure and the state of the engine are considered. First, among the fully-closed intake pressure values that change according to the engine speed, low-altitude (for example, atmospheric pressure = 760 mm)
Hg, equivalent to an altitude of 0 m), a typical fully closed intake pressure value PBL (Ne), and a high altitude (for example, atmospheric pressure = 460 mm)
Hg, a typical fully closed intake pressure value PBH (Ne) at an altitude of 4000 m) is stored in the ROM 206 in advance.

The fully closed intake pressure values PBL (Ne) and P
Using BH (Ne), as shown in FIG. 13, the operating state at that time (engine speed Ne = N1, intake pipe pressure P
b = P1), a parameter KR corresponding to the following (1)
Calculate based on the formula.

KR = {Pb−PBH (Ne)} / {PBL (Ne) −PBH (Ne)} (1)

Further, the parameter K obtained from the equation (1)
R, the low-land fully-closed intake pressure value PBL of the fully-closed intake pressure according to the atmospheric pressure at that time or the state of the engine 1 at that time.
An interpolation coefficient (1.0 at low altitude, 0 at high altitude) for (Ne) and the high altitude fully closed intake pressure value PBH (Ne) is calculated as a learning value KL. The learning value KL normalizes the fully closed intake pressure value according to the atmospheric pressure at that time.

Specifically, as shown in FIG. 14, when the atmospheric pressure decreases due to, for example, climbing a hill, the parameter KR when the throttle valve 4 is in the closed state also decreases, and the parameter KR is used. When KR is smaller than the learning value KL, the learning value KL is updated to the parameter KR at that time (portion A in FIG. 14).

On the other hand, in order to cope with a case where the atmospheric pressure rises due to a descending slope, it is determined whether or not the parameter KR is smaller than a predetermined value. If the parameter KR is smaller than the predetermined value, the vehicle is decelerated. It is determined that there is a possibility that the vehicle is going downhill, and the learning value KL is gradually increased (portion B in FIG. 14).

At this time, the deceleration state and the predetermined value serving as a criterion for descending a slope are determined in consideration of the variation of the engine 1 and the like.
It is set to a value larger than 0, for example, 1.2. Further, the gradually increasing speed of the learning value KL is set in accordance with a generally possible altitude changing speed at the time of descending a hill (for example, descending 1000 m in 30 minutes).

Normally, when the engine is decelerated on a flat ground, the parameter KR basically becomes 1.0.
It may vary by about 0%. Therefore, the predetermined value is set to about 1.2 described above so that the deceleration state can be determined even with an engine having a large variation.

On the other hand, when the vehicle is going downhill, the engine is in a deceleration state in most cases.
When it is determined that the vehicle is traveling downhill as described above.

Next, the learning value KL, the lowland fully closed intake pressure value PBL (Ne), and the highland fully closed intake pressure value PBH (N
e), based on the following equation (2), the predicted fully closed intake pressure PB according to the atmospheric pressure and the state of the engine 1 at that time.
Find C.

PBC = PBH (Ne) + {PBL (Ne) −PBH (Ne)} × KL (2)

Further, a value obtained by adding a predetermined value ΔPB to the predicted fully closed intake pressure PBC obtained from the equation (2) is compared with the intake pipe pressure Pb. If Pb <PBC + ΔPB, the throttle valve is in the closed state. Is determined. At this time, the predetermined value ΔPB is set to a value (for example, about 50 mmHg) at which no problem occurs even when the fuel cut or the idle speed control is performed as a result of the determination that the throttle valve 4 is in the closed state. Is done.

Next, the above operation according to the present invention will be described in more detail with reference to the flowchart of FIG. First, in step S701, it is determined whether or not the start flag is 0. If it is determined that the start flag is 0 (that is, YES), the process proceeds to step S702, and the learning value KL is set to 1.0 corresponding to a lowland. Initialize to

After the processing in the initialization step S702, the flow advances to step S703. On the other hand, in the start flag determination step S701, the start flag = 1 (that is, N
When it is determined as O), the process proceeds to step S703 without performing the process of step S702.

In step S703, a one-dimensional map is mapped from the engine speed Ne to obtain a high altitude fully closed intake pressure PBH (Ne).
H is stored in the RAM 205. Step S70
The process proceeds to step S4, where a one-dimensional map is mapped from the engine speed Ne to obtain the lowland fully closed intake pressure PBL (Ne), and is stored in the RAM 205 as the lowland fully closed intake pressure PBL.

Next, the routine proceeds to step S705, where the intake pipe pressure value Pb and the high altitude fully closed intake pressure PBH in the RAM 205 are stored.
The parameter KR is calculated based on the following equation (3) from the lowland fully closed intake pressure PBL.

KR = (Pb−PBH) / (PBL−PBH) (3)

Equation (3) corresponds to equation (1) described above. The parameter KR obtained from the equation (3)
5 is stored.

Then, the process proceeds to a step S706, wherein it is determined whether or not the parameter KR is smaller than a learning value KL.
If it is determined that KR <KL (that is, YES), the process proceeds to step S707, where the learning value KL is updated to the value of the parameter KR (A portion in FIG. 14), and then step S711 is performed.
Proceed to.

On the other hand, in step S706, KR ≧
If determined as KL (that is, NO), step S7
In step 08, it is determined whether the parameter KR is smaller than a predetermined value (= 1.2). If it is determined in step S708 that KR <1.2 (that is, YES), the process proceeds to step S709, and it is further determined whether or not the timing is every 100 ms.

If it is determined in step S709 that 100
If it is determined that the timing is every ms (ie, YES), the process proceeds to step S710, where the learning value KL is set to the predetermined value Δ
The learning value KL is updated by adding KL (part B in FIG. 14).
Then, the process proceeds to step S711.

On the other hand, in step S708, KR ≧
If it is determined to be 1.2 (that is, NO), or if it is determined in step S709 that the timing is not a timing every 100 ms (that is, NO), the process proceeds to step S711 without updating the learning value KL.

In step S711, the learning value KL
And the highland fully closed intake pressure PBH and the lowland fully closed intake pressure PBL, based on the following equation (4), the predicted fully closed intake pressure P
Calculate BC.

PBC = PBH + (PBL−PBH) × KL (4)

Equation (4) corresponds to equation (2) described above. The predicted fully closed intake pressure PBC obtained from the equation (4) is R
Stored in AM 205.

Next, the routine proceeds to step S712, where the intake pipe pressure Pb is compared with a value obtained by adding a predetermined value ΔPB to the predicted fully closed intake pressure PBC, and the added value PBC + Δ
It is determined whether it is smaller than PB. If Pb <PB
If it is determined that C + ΔPB (that is, YES), the process proceeds to step S713, and the valve closing flag is set to 1 to indicate that the throttle valve is in the closed state.

On the other hand, in step S712, Pb ≧
If it is determined that PBC + ΔPB (that is, NO), the process proceeds to step S714, and the valve closing flag is reset to 0 to indicate that the throttle valve is not closed. After the processing in steps S713 and S714, the process returns to processing step S8 in FIG.

As described above, without using the throttle sensor and the idle switch, the fully closed state of the throttle 4 is detected based on the comparison between the fully closed intake pressure value corresponding to the engine speed Ne and the actual intake pipe pressure Pb. By doing so, the cost of the entire apparatus can be reduced.

Further, a low-land fully closed intake pressure PBL and a high-land fully closed intake pressure PBH corresponding to the atmospheric pressure Pa around the vehicle are stored, and a learning value KL, which is an interpolation coefficient of both pressure values, is stored in the parameter KR. By calculating from the equation (1) based on the above, the predicted fully closed intake pressure PB taking into account the influence of the atmospheric pressure Pa
C can be calculated from equation (2).

Therefore, by comparing the predicted fully closed intake pressure value PBC corresponding to the atmospheric pressure Pa with the detected intake pressure value Pb, the fully closed state of the throttle valve 4 can be reliably determined without being affected by the atmospheric pressure Pa. Can be determined.

Embodiment 2 FIG. In the first embodiment, the fully closed intake pressure value at the high altitude and the fully closed intake pressure value at the low altitude are used for detecting the open / close state of the throttle valve 4. The operation may be simplified. Hereinafter, a second embodiment of the present invention using the fully closed intake pressure deviation will be described.
Will be described.

In this case, the pressure value calculating means in the control device 20 sets the value PBH corresponding to the intake pipe pressure when the throttle valve is closed at high altitude as the first pressure value, and sets the value PBH at low altitude when the throttle valve is closed at low altitude. The difference ΔP between the value corresponding to the intake pipe pressure and the first pressure value is defined as the second pressure value, and the parameter calculation means calculates the difference between the intake pipe pressure and the first pressure value PBH with respect to the second pressure value ΔP. The difference ratio is defined as a parameter KR.

Therefore, a typical fully closed intake pressure value PBH (N at high altitude, which varies according to the engine speed Ne.
e) and a typical fully closed intake pressure value PBH at high altitude
(Ne) and typical fully closed intake pressure value PBL at low altitude
(Ne), which is the difference from the fully closed intake pressure DPB (Ne).
May be stored in the ROM 206 in advance.

Thus, similarly to the above, as shown in FIG. 13, the operating state at that time (engine speed Ne = N
1, corresponding to the intake pipe pressure Pb = P1), the following (5)
The parameter KR can be calculated based on the equation.

KR = {Pb−PBH (Ne)} / {DPB (Ne)} (5)

Equation (5) corresponds to equation (1) described above, and PBL (Ne) -PBH (Ne) in equation (1) is expressed by D
BL (Ne).

Hereinafter, the learning value KL and the high altitude fully closed intake pressure value P
From BH (Ne) and the fully closed intake pressure deviation DPB (Ne), a predicted fully closed intake pressure PBC corresponding to the atmospheric pressure and the state of the engine at that time is obtained according to the following equation (6).

PBC = PBH (Ne) + DPB (Ne) × KL (6)

Equation (6) corresponds to equation (2) described above, and PBL (Ne) -PBH (Ne) in equation (2) is expressed by D
BL (Ne). The other points are exactly the same as those of the first embodiment, and the description thereof is omitted.

Next, the above-described operation according to the second embodiment of the present invention will be specifically described with reference to the flowchart of FIG. In the second embodiment of the present invention, the processing routine (FIG. 5) of the throttle valve opening / closing state detecting step S7 (FIG. 3) in the first embodiment is replaced with the processing routine of FIG.

In FIG. 6, S701 to S703, S7
06 to S710 and S712 to S714 are the same steps as described above, and S720, S721 and S722 are
These are steps corresponding to S704, S705, and S711, respectively. Accordingly, detailed description of the same processing steps as those in FIG. 5 will be omitted.

First, in the same manner as described above, the processes in steps S701 and S702 are performed, and in step S703, the high altitude fully closed intake pressure PBH is obtained, and then the flow proceeds to step S720. In step S720, a one-dimensional map is mapped from the engine speed Ne to obtain the fully closed intake pressure deviation DPB (Ne), and the fully closed intake pressure deviation Δ
It is stored in the RAM 205 as P.

Next, the routine proceeds to step S721, where the parameter K is calculated from the intake pipe pressure value Pb, the highland fully closed intake pressure PBH and the fully closed intake pressure deviation ΔP based on the following equation (7).
Calculate R.

KR = (Pb−PBH) / ΔP (7)

The equation (7) corresponds to the above-mentioned equation (3). The parameter KR obtained from the equation (7) is stored in the RAM 20
5 is stored. Thereafter, steps S706 to S710
After executing the processing of step S722, the process proceeds to step S722, where the learning value KL, the highland fully closed intake pressure PBH, and the fully closed intake pressure deviation ΔP
Then, the predicted fully closed intake pressure PBC is calculated based on the following equation (8).

PBC = PBH + ΔP × KL (8)

Equation (8) corresponds to equation (4) described above. The parameter KR obtained from the equation (8)
5 is stored. Then, after executing the processing of steps S712 to S714, the processing step S in FIG.
Return to 8. As described above, by using the fully closed intake pressure deviation ΔP, the step of subtracting the fully closed intake pressure value is omitted, so that the calculation is simplified.

Embodiment 3 FIG. Note that the first and second embodiments were used.
In the above, the bypass air flow rate was not considered, but the effect of the bypass air flow rate on the fully closed intake pressure may be considered. In this case, the closed state of the throttle valve 4 can be more reliably determined regardless of the change in the bypass air flow rate. Hereinafter, a third embodiment (corresponding to claim 4) of the present invention in which the bypass air flow rate is considered will be described.

In this case, the control device 20 controls the bypass air flow rate calculating means for estimating and calculating the bypass air flow rate QBYPS of the bypass intake passage 9, and the throttle valve 4 is closed in accordance with at least the engine speed Ne and the bypass air flow rate QBYPS. Pressure value calculating means for calculating the first and second pressure values related to the intake pipe pressure at the time of, and a parameter calculation for calculating a parameter KR representing a relationship between the first and second pressure values and the intake pipe pressure Pb. Means.

Generally, when the bypass air flow rate of the engine 1 increases, the fully closed intake pressure increases, and when the bypass air flow rate decreases, the fully closed intake pressure decreases. Therefore, in the first or second embodiment in which the change in the fully closed intake pressure due to the bypass air flow rate is not considered, if the bypass air flow rate changes when predicting the fully closed intake pressure, even if the accelerator is released, There are problems that the throttle valve cannot be determined to be in the closed state or that the throttle valve is determined to be in the closed state even when the accelerator is depressed.

Thus, in Embodiment 3 of the present invention,
An air flow rate QBYPS in the bypass intake passage 6 that bypasses the throttle valve 4 of the engine 1 is estimated and calculated, and a predicted fully closed intake pressure PB is calculated according to the bypass air flow rate QBYPS.
Find C.

First, among the intake pressures that change according to the engine speed Ne , the bypass air flow rate at low altitude is 0%.
And a typical fully closed intake pressure value PBLZ (Ne) at
The bypass air flow rate in lowland is 256 liter / sec
Typical fully closed intake pressure value PBLF (Ne) at c
And a typical fully closed intake pressure value PBHZ (Ne) when the bypass air flow rate at high altitude is 0, and a typical fully closed intake pressure value PBHF (Ne) when the bypass air flow rate at high altitude is 256 l / sec. ) And ROM
206.

Next, as shown in FIG. 15, the lowland fully closed intake pressure PBL corresponding to the bypass air flow rate QBYPS, and the highland fully closed intake pressure PBL corresponding to the bypass air flow rate QBYPS.
BH is calculated based on the following equations (9) and (10).

PBL = {PBLZ (Ne) × (256-QBYPS) + PBLF (Ne) × QBYPS} / 256 (9)

PBH = {PBHZ (Ne) × (256-QBYPS) + PBHF (Ne) × QBYPS} / 256 (10)

From the equations (9) and (10), the lowland fully closed intake pressure PBL and the highland fully closed intake pressure PBH when the bypass air flow rate QBYPS is considered are obtained. Further, a parameter KR is calculated based on the following equation (11).

KR = (Pb−PBH) / (PBL−PBH) (11)

The expression (11) is obtained by the expression (1) and the expression (3).
Equation (5) or (7). The parameter KR obtained from the equation (11) is stored in the RAM 205. The processing operations other than those described above are exactly the same as those in the first or second embodiment, and thus description thereof will be omitted.

Next, the above-mentioned operation of the third embodiment of the present invention will be specifically described with reference to the flowchart of FIG. FIG. 7 shows a throttle valve open / closed state detection routine (step S7) in FIG. In FIG. 7, S7
01, S702 and S705 to S714 are the same steps as those in FIG. 5, and S733 and S734 correspond to steps S703 and S704 in FIG. 5, respectively. Therefore, the description of the same processing steps as those in FIG. 5 will be omitted.

In the case of FIG. 7, steps S730 to S732 are performed.
Has been added. First, as described above, step S7
01 and the process of step S702, the process proceeds to step S730, and the air conditioner switch 12 (see FIG. 1)
Is turned on.

If the air conditioner switch 12 is off (ie, NO), there is no need to increase the flow rate of the bypass air.
It is fully closed by the valve 11.

Accordingly, the flow proceeds to step S731, where a one-dimensional map (see FIG. 12) corresponding to the cooling water temperature value WT is mapped, and the FIA valve 7 has a FIA air flow rate QFIA (WT) corresponding to the air flow rate in the FIA passage 6a. Is obtained, the ISC air flow rate QISC corresponding to the air flow rate of the ISC bypass passage 10 obtained in step S9 of FIG. 3 is added to the FIA air flow rate QFIA (WT), and the bypass air passage 6 The bypass air flow rate QBYPS, which is a value corresponding to the air flow rate, is obtained and stored in the RAM 205.

On the other hand, if the air conditioner switch is ON in step S730, the A / C bypass passage 9 is
It is fully opened by the S valve 11. Therefore, in step S732, the FIA air flow rate QFIA (WT) is obtained in the same manner as in step S731, and this FIA air flow rate QFI
A (WT) is added to the ISC air flow rate QISC, and the A / C air flow rate QAC corresponding to the air flow rate of the A / C bypass passage 9 previously stored in the ROM 206 is added to the bypass air passage. The bypass air flow rate QBYPS, which is a value corresponding to the air flow rate of No. 6, is obtained and stored in the RAM 205.

After the processing in steps S731 and S732, the process proceeds to step S733, where a typical fully-closed intake air when the bypass air flow rate at high altitude, which varies according to the bypass air flow rate QBYPS and the engine speed, is 0, is obtained. From the pressure value PBHZ (Ne) and the typical fully closed intake pressure value PBHF (Ne) when the bypass air flow rate at high altitude is 256 l / sec, the high altitude fully closed according to the bypass air flow rate QBYPS according to the above equation (10). The intake pressure PBH is obtained and stored in the RAM 205.

Next, the flow proceeds to step S734, in which the previously determined bypass air flow rate QBYPS and the representative fully closed intake pressure value PBL when the bypass air flow rate in lowland is 0 are set.
Z (Ne) and the bypass air flow rate at lowland is 256
Typical fully closed intake pressure value PB at liter / sec
From LF (Ne), a lowland fully-closed intake pressure PBL corresponding to the bypass air flow rate QBYPS is obtained according to the above equation (9), and stored in the RAM 205.

Thereafter, similarly to the above, step S705
処理 S714 are executed, and the process returns to the process of FIG. As described above, by obtaining the highly reliable predicted fully closed intake pressure value PBC based on the lowland fully closed intake pressure value PBLZ and the highland fully closed intake pressure value PBHZ in consideration of the bypass air flow rate, the throttle valve closed state is determined. The determination can be made reliably.

Embodiment 4 FIG. In the first embodiment, in step S702, the learning value KL is initialized to 1.0 corresponding to lowland. However, a one-dimensional map corresponding to the atmospheric pressure Pa is mapped to initialize the learning value KL to the initial value KLINIT (Pa ) May be required. In this case, erroneous determination of the throttle valve closed state can be prevented.

Hereinafter, the fourth embodiment of the present invention using the initial value KLINIT (Pa) mapped as the learning value KL.
(Corresponding to claim 5) will be described. In this case, the control device 20 determines the initial value KL of the learning value based on the atmospheric pressure Pa.
A learning value initial value calculating means for calculating INIT (Pa) is included.

For example, as in the first embodiment, the learning value KL
If the initial value of is set to 1.0, the racing value KL is updated to the atmospheric pressure at that time when the accelerator is lightly depressed and the throttle valve 4 is not returned to the closed state at all and the accelerator pedal is lightly depressed. And remains at 1.0.
Therefore, if the intake pressure at that time is equal to or lower than the fully closed intake pressure in the lowland, it is determined that the throttle valve 4 is in the closed state, the fuel cut is performed, and the engine speed Ne drops. I do.

Thus, in Embodiment 4 of the present invention,
At the start of the engine, the atmospheric pressure Pa is detected.
Mapping a one-dimensional map (see FIG. 16) corresponding to
The initial value KLINIT (Pa) of the learning value is obtained, and the learning value K is obtained.
Stored as L. The processing operations other than those described above are exactly the same as those in the first embodiment, and thus description thereof is omitted.

Next, the operation of the fourth embodiment will be specifically described with reference to the flowchart of FIG. FIG. 8 shows a throttle valve open / closed state detection routine (step S7) in FIG. 3, and in FIG.
3 to S714 are the same as the steps in FIG.
0 corresponds to step S702. Accordingly, detailed description of the same processing steps as those in FIG. 5 will be omitted.

First, in step S701, it is determined whether or not the start flag is 0. If the start flag is 0 (that is, YES), the process proceeds to step S740, and FIG.
16 according to the atmospheric pressure value Pa obtained in step S6 of FIG.
Is mapped, and KLINIT (Pa), which is an initial value of the learning value, is set as the learning value KL in the RAM 205.
To be stored. After the processing of step S740, step S740
Proceed to 703.

On the other hand, if it is determined in step S701 that the start flag is 1 (ie, NO), the flow directly proceeds to step S703. Then, as before,
The processing in steps S703 to S714 is executed, and the process returns to the processing in FIG. As described above, since the learning value initial value KLINIT (Pa) corresponding to the atmospheric pressure value Pa is calculated and calculated, a highly reliable learning value KL can be obtained. Therefore, it is possible to prevent erroneous determination of the throttle closed state. Can be.

Embodiment 5 FIG. Note that the first or second embodiment is used.
Then, as an initial value of the learning value KL, a value corresponding to lowland 1.0
Is set (step S702), and equations (1) and (3) are set.
Or the difference ΔP between the lowland fully-closed intake pressure PBL and the highland fully-closed intake pressure PBH, as in the equations (5) and (7),
The difference between the intake pipe pressure Pb and the highland fully closed intake pressure PBH (Pb
-PBH) is calculated as a parameter KR (step S705 or S721).

When the parameter KR is smaller than the learning value KL, the parameter KR is stored as the learning value KL (step S707), and the parameter KR is larger than the learning value KL and smaller than a predetermined value (= 1.2). Sometimes, the learning value KL is gradually increased and stored (step S7).
10).

Finally, the fully closed intake pressure deviation ΔP and the learning value K
L and the value (ΔP · KL) multiplied by L and the high altitude fully closed intake pressure P
The value (PBH + ΔP · KL) obtained by adding BH is calculated as the predicted fully closed intake pressure PBC (Step S711 or S711).
722), when the intake pipe pressure Pb is equal to the predicted fully closed intake pressure PBC
It is determined that the throttle valve 4 of the engine 1 is in the closed state when the value is smaller than the value (PBC + ΔPB) obtained by adding the predetermined value and the predetermined value ΔPB.

However, in Embodiment 5 of the present invention,
Set the lowland equivalent value 0 as the initial value of the learning value KL .
The fully closed intake pressure deviation ΔP and the lowland fully closed intake pressure PBL
The ratio of the difference between the pressure and the intake pipe pressure Pb is calculated as a parameter KR .

In this case, subsequently, the embodiment 1 or the embodiment 2
Conversely, when the parameter KR is larger than the learning value KL, the parameter KR is stored as the learning value KL, and the parameter KR is smaller than the learning value KL and the predetermined value (= −
0.2), the learning value KL is gradually reduced and stored.

Further, a value (ΔP · KL) obtained by multiplying the learning value KL to the fully closed intake pressure deviation ΔP is subtracted from the lowland fully closed intake pressure PBL, and this value (PBL−DPB · KL) is used as the predicted fully closed intake pressure. It is calculated as PBC. Finally, as described above, when the intake pipe pressure Pb is smaller than the value (PBC + ΔPB) obtained by adding the predetermined value ΔPB to the predicted fully closed intake pressure PBC, it is determined that the throttle valve 4 of the engine 1 is in the closed state. .

Embodiment 6 FIG. In the third embodiment, in step S712 in FIG. 7, the predicted fully closed intake pressure PBC
(PBC + ΔPB), which is obtained by adding と PB and a predetermined value ΔPB,
The detected intake pipe pressure Pb is compared with Pb <PBC +
If ΔPB, it is determined that the throttle valve is closed (step S
713) However, the value (KL + ΔKC) obtained by adding the predetermined value ΔKC to the learning value KL is compared with the parameter KR,
If R <KL + ΔKC, it may be determined that the throttle valve is closed.

In Embodiment 6 of the present invention (corresponding to Claims 6 and 7), the control device 20 sets the parameter KR
Includes a throttle valve closed state detecting means for determining that the throttle valve 4 is in the closed state when is smaller than the learning value KL in a predetermined relationship. The throttle valve closed state detecting means determines that the throttle valve 4 is closed when the parameter KR is smaller than a value obtained by adding a predetermined value ΔKC to the learning value KL.

In this case, since it is not necessary to calculate the predicted fully closed intake pressure PBC, the calculation is simplified. Less than,
A description will be given of a sixth embodiment of the present invention in which the minimum parameter value is used as a comparison criterion.

For example, in the third embodiment, the parameter KR is calculated from the above equation (11), and the interpolation coefficient of the full-closed intake pressure values PBL and PBH, that is, the learning value KL is calculated based on the parameter KR. The predicted fully closed intake pressure PBC is calculated from the equation (4) based on the learning value KL.

However, here, it can be understood that the following equation (12) is obtained by modifying equation (11).

Pb = PBH + (PBL−PBH) × KR (12)

Therefore, from equation (12), Pb <PBC +
Instead of determining whether or not ΔPB, KR <KL + ΔKC
It is determined whether or not KR <KL + ΔKC,
It is only necessary to determine that the throttle valve 4 is in the closed state. However, the predetermined value ΔKC is expressed by the following expression (13) using the aforementioned predetermined value ΔPB.

ΔKC = ΔPB / (PBL−PBH) (13)

As a result, the calculation of equation (4) for obtaining the predicted fully closed intake pressure PBC becomes unnecessary, and the calculation can be omitted to simplify the calculation.

Next, the above-mentioned operation of the sixth embodiment of the present invention will be specifically described with reference to the flowchart of FIG. FIG. 17 shows a throttle valve open / closed state detection routine according to Embodiment 6 of the present invention.
701, S706 to S710, S713, S714 and S730 to S734 are the same as the steps in FIG.
Step S740 is the same as the step in FIG. here,
Step S740 of the fourth embodiment is applied as an initial setting step of the learning value KL. Step S741 corresponds to the determination step S712 in FIG.

As described above, first, if it is determined in step S701 that the start flag is 0, the process proceeds to step S740, and a one-dimensional map (FIG. 3) is obtained according to the atmospheric pressure value Pa obtained in step S6 (see FIG. 3). 16), the initial learning value KLINIT (P
a) is obtained and stored in the RAM 205 as the learning value KL.

[0186] If it is determined in step S730 that the air conditioner switch 12 is turned off, the process proceeds to step S73.
In step 1, by mapping a one-dimensional map (FIG. 12) corresponding to the cooling water temperature value WT, a FIA air flow rate QFIA (WT) corresponding to the air flow rate of the FIA passage 6a by the FIA valve 7 is obtained. The bypass air flow rate QBYPS is obtained by adding the ISC air flow rate QISC obtained in S9, and stored in the RAM 205.

If it is determined in step S730 that the air conditioner switch is on, then in step S732 F
The IA air flow rate QFIA (WT) is obtained, and the ISC air flow rate QISC and the air conditioner air flow rate QAC are added thereto to obtain a bypass air flow rate QBYPS.
To be stored.

Next, in step S733, the bypass air flow rate QBYPS, the high altitude fully closed intake pressure value PBHZ (Ne) when the bypass air flow rate is 0, and the high altitude fully closed intake pressure when the bypass air flow rate is 256 l / sec. From the value PBHF (Ne), the high-altitude fully-closed intake pressure P corresponding to the bypass air flow rate QBYPS according to the above equation (10).
The BH is obtained and stored in the RAM 205.

In step S734, the bypass air flow rate QBYPS, the lowland fully closed intake pressure value PBLZ (Ne) when the bypass airflow rate is 0, and the lowland fully closed intake pressure value when the bypass air flow rate is 256 liter / sec. From PBLF (Ne), the lowland fully closed intake pressure PBL corresponding to the bypass air flow rate QBYPS according to the above equation (9)
Is obtained and stored in the RAM 205.

Next, in step S705, a parameter KR is calculated from the intake pipe pressure value Pb, the highland fully closed intake pressure PBH and the lowland fully closed intake pressure PBL based on the above equation (11), and stored in the RAM 205.

Subsequently, in step S706, the parameter KR is compared with the learning value KL. If KR <KL, the learning value KL is updated to the value of the parameter KR in step S707 (A in FIG. 14). If KR ≧ KL, the parameter KR is compared with a predetermined value 1.2 in step S708.

If KR <1.2, it is determined in step S709 whether or not the timing is every 100 ms.
At 710, the learning value KL is updated by adding the predetermined value ΔKL to the learning value KL (portion B in FIG. 14). If KR ≧ 1.2 or the timing is not every 100 ms, the learning value KL is not updated. The above processing operations are the same as described above.

Next, in step S741, the parameter KR is compared with a value (KL + ΔKC) obtained by adding a predetermined value ΔKC to the learning value KL, and it is determined whether or not the parameter KR is smaller than the added value (KL + ΔKC). .

If KR <KL + ΔKC (that is, YE
If it is determined as S), the process proceeds to step S713, and the valve closing flag is set to 1 to indicate that the throttle valve is in the closed state. Also, KR ≧ KL + ΔKC (that is, N
When it is determined as O), the process proceeds to step S714, and the valve closing flag is reset to 0 to indicate that the throttle valve is not in the closed state. Step S713 and Step S
After the process of 714, the process returns to the process of FIG.

Embodiment 7 FIG. Next, a description will be given of a seventh embodiment (corresponding to claims 8 and 9) of the present invention in which erroneous learning of the learning value KL at the time of a sudden change in the engine state is prevented.

In this case, the control device 20 controls the first and second
A filtered pressure value calculating means for performing a filtering process on the pressure values of (a) and (b) to calculate first and second filtered pressure values, and an intake pipe pressure Pb for the first and second filtered pressure values
And a parameter calculation means for calculating a parameter KR representing the relationship.

The post-filter pressure value calculation means performs a first low-pass filter process on the first and second pressure values to obtain first and second post-filter pressure values PBHF and PBLF.
The parameter calculation means calculates the ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the second filtered pressure value and the first filtered pressure value as a parameter KR
And

Hereinafter, referring to FIGS. 18 and 19,
The operation of the seventh embodiment of the present invention will be described. FIG. 18 is a timing chart showing time changes of the engine speed Ne, the intake pipe pressure (detected value) Pb, the parameter KR, and the learning value KL during braking, and FIG. 19 is a bypass air flow rate QBYPS when the air conditioner is turned on, the intake pipe pressure. (Detected value) P
6B is a timing chart showing a time change of a parameter KR and a learning value KL.

In FIGS. 18 and 19, the intake pipe pressure (detected value) Pb is shown by a dashed line, the fully closed intake pressure values PBL and PBH before the filter processing are shown by solid lines, and the fully closed intake pressure after the filter processing. The pressure values PBLF and PBHF are indicated by broken lines, and the parameter KR and the learning value KL based on the fully-closed intake pressure values PBL and PBH before the filtering process are as follows .
The parameter KR and the learning value KL based on the fully closed intake pressure values PBLF and PBHF after the filtering process are indicated by a dashed line and a dashed line, respectively.

For example, in the third embodiment, the predicted fully closed intake pressure PBC is predicted from the engine speed Ne and the bypass air flow rate QBYPS. However, actually, the operation delay of the actuator for adjusting the bypass air flow rate QBYPS is performed. , The response delay of the pressure sensor 14, or the control device 20
, The detected value Pb of the intake pipe pressure is delayed with respect to the actual change in the intake pipe pressure.

Therefore, the detected value Pb of the intake pipe pressure is relatively smaller than the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure value PBH obtained according to changes in the engine speed Ne and the bypass air flow rate QBYPS. The timing will be delayed. For example, as shown in FIG. 18, when the engine speed Ne suddenly decreases due to braking or the like,
Lowland fully closed intake pressure value PBL and highland fully closed intake pressure value PBH
, The timing of the increase of the intake pipe pressure Pb is delayed.

As a result, the parameter KR obtained by the above equation (11) temporarily drops below its normal value, and the learning value KL also drops (see the solid line in FIG. 18). Since the learning value KL is updated over a relatively long period of time, once it decreases, it does not return to the normal value for a while as indicated by the two-dot chain line, and during this period, the closed state of the throttle valve 4 cannot be detected.

As shown in FIG. 19, when the air conditioner is turned on from off, the bypass air flow rate Q
When BYPS is rapidly increased, the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure value P
The increase in the intake pipe pressure Pb is delayed with respect to the increase in BH. Therefore, the parameter K obtained by the above equation (11)
R temporarily drops below the normal value, and as a result, the learning value K
Since L also decreases and does not return to the normal value for a while, there is a problem that the closed state of the throttle valve 4 cannot be detected.

Therefore, in Embodiment 7 of the present invention,
Lowland fully closed intake pressure value PBL and highland fully closed intake pressure value PB
H is subjected to first-order low-pass filtering according to the following equations (14) and (15) . Thus, the filtered lowland fully closed intake pressure value PBLF and the filtered highland fully closed intake air that are delayed from the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure value PBH in accordance with the delay of the detected intake pipe pressure value Pb. A pressure value PBHF is determined.

PBFLF ← PBLF × KFILT + PBL × (1-KFILT) (14) PBHFＰPBHF × KFILT + PBH × (1-KFILT) (15)

By the filter processing of the equations (14) and (15), the change in the filtered lowland fully closed intake pressure value PBLF and the filtered highland fully closed intake pressure value PBHF and the change in the detected intake pipe pressure value Pb are obtained. Will be relatively consistent. Hereinafter, using the filtered lowland fully closed intake pressure value PBLF and the filtered highland fully closed intake pressure value PBHF,
The parameter KR is calculated based on the following equation (16) corresponding to the equation (1).

KR = (Pb−PBHF) / (PBLF−PBHF) (16)

By calculating the parameter KR using the filtered full-closed intake pressure values PBLF and PBHF as in the equation (16), when the engine speed Ne suddenly decreases or when the bypass air flow rate QBYPS suddenly increases. Even if the fully-closed intake pressure PBL or PBH suddenly increases as shown in FIG. 19, the parameter KR will not fall below the normal value as shown by the broken line (KR ') in FIGS.

Therefore, the learning value KL is represented by a dashed line (KL ').
Thus, the closed state of the throttle valve 4 can be accurately detected by using the accurate learning value KL that does not decrease.

Next, the above-described operation according to the seventh embodiment of the present invention will be specifically described with reference to the flowchart in FIG. In FIG. 20, S701, S706-
Steps S714, S730 to S734, and S740 are the same steps as described above, and step S744 corresponds to step S705. S742 and S743 are newly added filter processing steps.

Therefore, description of the same steps as described above will be omitted. First, in steps S701, S740 and S730 to S734, the bypass air flow rate QBY
After obtaining the highland fully closed intake pressure PBH and the lowland fully closed intake pressure PBL according to the PS, the filter processing step S742 is performed.
Then, the process proceeds to S743.

In step S742, the high altitude fully closed intake pressure PBH is subjected to the primary low-pass filter processing based on the above equation (15), and the filtered high altitude fully closed intake pressure PBH is applied.
It is stored in the RAM 205 as HF. Step S7
In 43, the low-pass fully-closed intake pressure PBL is subjected to a primary low-pass filtering process based on the above equation (14), and is stored in the RAM 205 as a post-filtered low-coverage fully-closed intake pressure PBLF.

Next, in step S744, the intake pipe pressure value Pb, the filtered highland fully closed intake pressure PBHF, and the filtered lowland fully closed intake pressure PBLF are used to determine the (1)
6) Calculate the parameter KR based on the equation
5 is stored. Hereinafter, similarly to the above, step S706
From S714, it is determined whether or not the throttle valve 4 is in the closed state, and the valve closing flag is set or reset. Then, the process returns to the processing in FIG.

Embodiment 8 FIG. In the seventh embodiment, in order to prevent erroneous learning when the intake pipe pressure Pb suddenly increases,
The filter processing is always performed.
As in (corresponding to claims 10 and 11), filter processing may be selectively performed to prevent erroneous learning when the intake pipe pressure Pb sharply decreases.

In this case, the control device 20 filters the first pressure value only when it determines that the intake pipe pressure when the throttle valve 4 is closed is in the increasing direction based on the first pressure value. First filtered pressure value calculating means for calculating the first filtered pressure value, and determining that the intake pipe pressure when the throttle valve 4 is closed is in the increasing direction based on the second pressure value. Only when the second pressure value is filtered, a second filtered pressure value calculating means for calculating a second filtered pressure value by filtering the second pressure value, and an intake pipe pressure with respect to the first and second filtered pressure values. Parameter calculating means for calculating a parameter representing the relationship.

Further, the first post-filter pressure value calculating means comprises:
The first pressure value PBH is equal to the first filtered pressure value PBHF.
Only when the pressure value is larger than the first pressure value, the first pressure value is subjected to a first-order low-pass filter processing to obtain a first filtered pressure value.
Is larger than the second filtered pressure value P BLF only when the second filtered pressure value is larger than the second filtered pressure value P BLF to obtain a second filtered pressure value by performing a primary low-pass filtering process. The ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the post-pressure value and the first filtered pressure value is used as a parameter.

An eighth embodiment of the present invention in which erroneous calculation of the parameter KR and the learning value KL can be prevented will be described below with reference to FIG. FIG. 21 is a timing chart showing temporal changes in the bypass air flow rate QBYPS, the intake pipe pressure Pb, the parameter KR, and the learning value KL when the air conditioner is shut off.
In FIG. 21, a solid line, a two-dot chain line, a dashed line, and a one-dot chain line indicate the same ones in FIGS. 18 and 19, respectively.

In the seventh embodiment, the parameter K is set regardless of the variation in the delay time of the detected intake pipe pressure value Pb.
If it is attempted to prevent R from falling below the normal value, the delay time due to the first-order low-pass filtering is determined by the intake pipe pressure detection value Pb.
, The coefficient KFILT (0 to 1) of the first-order low-pass filter processing must be set to a relatively large value so as not to become smaller than the maximum value of the delay time of.

Therefore, for example, as shown in FIG. 21, when the bypass air flow rate QBYPS suddenly decreases due to the air conditioner being cut off from on to off, the filtered lowland fully closed intake pressure value PBLF and the filtered highland fully closed intake air are reduced. As the pressure value PBHF (dashed line) decreases, the intake pipe pressure Pb (dashed line) decreases faster.

As a result, the parameter KR calculated from the above equation (16) temporarily drops below the normal value (FIG. 21).
(See dashed line KR 'in FIG. 21), the learning value KL also decreases (see dashed line KL' in FIG. 21), and as described above, the learning value KL does not return to the normal value for a while, so the throttle valve Disadvantageously that the closed state cannot be detected.

Therefore, in Embodiment 8 of the present invention,
When the lowland fully-closed intake pressure PBL is smaller than the filtered lowland fully-closed intake pressure PLFF, it is determined that the engine state is such that the fully-closed intake pressure is in a decreasing direction, and the primary low-pass filter processing is performed by the above equation (14). The lowland fully-closed intake pressure PBLF is directly filtered after the lowland fully-closed intake pressure PBL is filtered.
Set as

Similarly, when the highland fully closed intake pressure PBH is smaller than the filtered highland fully closed intake pressure PBHF, it is determined that the engine state is such that the fully closed intake pressure is decreasing.
The high altitude fully closed intake pressure PBH is set as it is as a filtered high altitude fully closed intake pressure PBHF without executing the primary low-pass filter processing by the above equation (15).

As described above, by selectively performing the filter processing and prohibiting the filter processing at the time of the sudden decrease in the fully closed intake pressure, the parameter KR is obtained as shown by the solid line in FIG.
Will not fall below the normal value.

Therefore, the fully closed intake pressure rapidly decreases, as in the case where the engine speed Ne suddenly increases due to a clutch meeting or the like, or when the bypass air flow rate sharply decreases because the air conditioner is cut off from on to off. Even
It is possible to prevent the learning value KL from being reduced as indicated by the alternate long and short dash line, and to accurately detect the closed state of the throttle valve 4. The other points are exactly the same as in the seventh embodiment, and the description thereof is omitted.

Next, the above operation according to the eighth embodiment of the present invention will be specifically described with reference to the flowchart in FIG. In FIG. 22, S701, S730-S730
Steps S734, S740, and S742 to S744 are the same steps as described above, and steps S745 to S748 are determination and prohibition steps of a newly added filter process.

Steps after step S 706 following step S 744 are the same as those in FIG. 20 and are not shown.
The description of the same steps as described above is omitted.
First, steps S701, S740 and S730-S7
34, the high altitude fully closed intake pressure PBH and the low altitude fully closed intake pressure PBL corresponding to the bypass air flow rate QBYPS are obtained, and then the flow proceeds to the filter processing determination step S745.

In step S745, it is determined whether or not the highland fully closed intake pressure PBH is higher than the filtered highland fully closed intake pressure PBHF. If it is determined that PBH> PBHF (that is, YES), the fully closed state is determined. Judging that the intake air pressure is in the increasing engine state, the high altitude fully closed intake pressure PB
The process proceeds to a filter processing step S742 for H, and calculates a post-filter highland fully closed intake pressure PBHF.

On the other hand, if it is determined that PBH ≦ PBHF (that is, NO), it is determined that the engine state is such that the fully-closed intake pressure is decreasing, and the filtering process is prohibited in step S74.
The program then proceeds to 6, and stores the highland fully closed intake pressure PBHF as it is as the filtered highland fully closed intake pressure PBHF.

Next, after execution of the filter processing step S742 or the filter processing prohibition step S746, the filter processing determination step S7 for the lowland fully closed intake pressure PBL is performed.
Proceeding to 47, it is determined whether the lowland fully closed intake pressure PBL is greater than the filtered lowland fully closed intake pressure PLFF.

If PBL> PBLF (that is, YES)
When it is determined that the engine state is such that the fully closed intake pressure is in the increasing direction, the process proceeds to the filter processing step S743 for the lowland fully closed intake pressure PBL to calculate the filtered lowland fully closed intake pressure PBLF.

On the other hand, if it is determined that PBL ≦ PBF (that is, NO), it is determined that the engine state is such that the fully closed intake pressure is decreasing, and the flow advances to step S748 to filter the lowland fully closed intake pressure PBL as it is. This is stored as a rear lowland fully closed intake pressure PBLF.

Next, after execution of the filter processing step S743 or the filter processing prohibition step S748, the flow advances to step S744 to execute the processing of step S744 and steps S706 to S714 similarly to the seventh embodiment (FIG. 20). The process returns to step 3. In this way, by prohibiting the filter processing when the intake pipe pressure suddenly decreases, the intake pipe pressure P
It is possible to reliably prevent the learning value KL from decreasing in an engine transient state in which b changes rapidly.

Embodiment 9 FIG. In the eighth embodiment, the sudden decrease in the predicted fully closed intake pressure PBC at the time of the rapid decrease in the intake pipe pressure is not taken into consideration. However, as in the following ninth embodiment (corresponding to claim 12), the predicted fully closed intake pressure PBC is On the other hand, by performing filter processing selectively, a sudden decrease in the predicted fully closed intake pressure PBC may be prevented.

In this case, control device 20 determines pressure estimated value P
Only when it is determined that the pressure estimation value PBC is in the decreasing direction based on the BC, the filtered pressure estimation value PBC is subjected to filter processing to calculate the filtered pressure estimation value PBCF, A throttle valve closed state detecting means for determining that the throttle valve is in a closed state when the pipe pressure is small in a predetermined relation to the filtered pressure estimated value.

A ninth embodiment of the present invention for preventing a sudden decrease in the predicted fully closed intake pressure PBC will be described below with reference to FIG.

FIG. 23 is a timing chart showing the time change of the bypass air flow rate QBYPS, the intake pipe pressure Pb, and the valve closing flag when the air conditioner is turned on and off. In FIG. 23, the fully closed intake pressure values PBL and PBH are shown by solid lines. , The intake pipe pressure Pb is indicated by a dashed line, and a predetermined value ΔPB is added to the predicted fully closed intake pressure PBC before the filtering process .
The value is indicated by a broken line, and the value obtained by adding a predetermined value ΔPB to the predicted fully closed intake pressure PBCF after the filter processing is indicated by a two-dot chain line.

In the eighth embodiment, as shown in FIG. 23, for example, when the bypass air flow rate QBYPS suddenly decreases due to the air conditioner being shut off from on to off, the predicted fully closed intake pressure value PBC (broken line) decreases. Intake pipe pressure P
b (dot-dash line) is delayed, so that Pb ≧
PBC + ΔPB.

Therefore, the above-described steps S712 and S7
23, the valve closing flag is temporarily reset to 0 (portion A in FIG. 23). As a result, for example, a problem occurs in which the fuel cut is temporarily interrupted and drivability is impaired.

Therefore, in Embodiment 9 of the present invention,
As described below, the sudden decrease of the predicted fully closed intake pressure value PBC is prevented by the filter processing. That is, after calculating the predicted fully closed intake pressure value PBC in the same manner as in the eighth embodiment, the predicted fully closed intake pressure value PBC is compared with the filtered fully closed intake pressure value PBCF after filtering. If it is smaller than the predicted fully closed intake pressure PBCF after filtering, it is determined that the predicted fully closed intake pressure PBC has decreased, and the predicted fully closed intake pressure PBCF after filtering is calculated based on the following equation (17). .

PBCF = PBCF × KPBCF + PBC × (1-KPBCF) (17)

On the other hand, when the predicted fully closed intake pressure PBC is equal to or larger than the filtered fully closed intake pressure PBCF after filtering, it is determined that the predicted fully closed intake pressure PBC has increased, and the predicted fully closed intake pressure PBC is left unchanged. It is stored as the post-filtering predicted fully closed intake pressure value PBCF. That is, in this case, the filter processing of the predicted fully closed intake pressure value PBC is prohibited. The post-filter predicted fully closed intake pressure value PBCF thus obtained is used for detecting the open / closed state of the throttle valve 4 as described below.

That is, the post-filter predicted fully closed intake pressure PBC
Value obtained by adding predetermined value ΔPB to F (PBCF + ΔPB)
And Pb <PBCF + ΔP
If B, it is determined that the throttle valve 4 is closed.

With the above processing, the predicted fully closed intake pipe pressure P
Only when BC decreases, the determination value (PBCF + ΔPB) for determining whether or not the throttle valve 4 is closed can be delayed from being reduced, so that the valve closing flag is prevented from being temporarily reset to 0. (Part B in FIG. 23). The other points are exactly the same as in the eighth embodiment, and the description thereof is omitted.

Next, the above operation according to the ninth embodiment of the present invention will be specifically described with reference to the flowchart in FIG. In FIG. 24, S706 to S711,
S713 and S714 are the same steps as described above,
Step S752 corresponds to step S712. Steps S701, S740, S730-S734, S74
Steps S748 and S744 are not shown because they are the same as those in FIG. The description of the same processing as in the eighth embodiment is omitted.

Steps S749 to S751 are a judgment step, a filter processing step, and a filter processing prohibition step of the predicted fully closed intake pressure value PBC additionally inserted in order to prevent a sudden decrease in the predicted fully closed intake pressure value PBC.

First, the learning value KL and the parameter KR are calculated by the processing routine shown in FIG. 22, and then, at steps S706 to S711, the predicted fully closed intake pressure PB
After C is calculated, in step S749, the predicted fully closed intake pressure value PBC is changed to the filtered fully closed intake pressure value Pafter filtering.
It is determined whether it is smaller than BCF.

If PBC <PBCF (ie, YES)
When it is determined that the intake air pressure value P after filtering is predicted based on the above equation (17), the process proceeds to step S750.
The BCF is calculated and stored in the RAM 205.

On the other hand, if it is determined that PBC ≧ PBCF (that is, NO), the filtering process is prohibited at step S751.
Then, the predicted fully closed intake pressure value PBC is stored as it is as the filtered fully closed intake pressure value PBCF after filtering. After the processing in step S750 or S751, the intake pipe pressure Pb
The process proceeds to the determination step S752.

In step S752, the intake pipe pressure Pb is compared with a value (PBCF + ΔPB) obtained by adding a predetermined value ΔPB to the filtered fully closed intake pressure PBCF after filtering.
It is determined whether the intake pipe pressure Pb is smaller than the added value (PBCF + ΔPB).

Hereinafter, Pb <PBCF + ΔPB (that is, Yb
ES), the process proceeds to step S713,
Set the valve closing flag indicating the throttle valve closed state to 1,
If it is determined that Pb ≧ PBCF + ΔPB (that is, NO), the process proceeds to step S714 to reset the valve closing flag to 0 to indicate that the throttle valve 4 is not closed, and returns to the processing in FIG.

Embodiment 10 FIG. In addition, the above-mentioned Embodiments 7 to 9
Then, the lowland fully closed intake pressure PBL and the highland fully closed intake pressure PB
H was used for the calculation, but similarly to the above-described second embodiment, the lowland fully closed intake pressure PBL and the highland fully closed intake pressure PBH were used.
Is determined in advance as a fully closed intake pressure deviation ΔP.
In order to simplify the calculation.

Embodiment 11 FIG. In the seventh and eighth embodiments, the value obtained by adding the predetermined value ΔPB to the predicted fully closed intake pressure PBC is compared with the intake pipe pressure Pb. However, the learning value KL is similar to the sixth embodiment. May be compared with a value obtained by adding a predetermined value ΔKC to the parameter KR.

Similarly, in the ninth embodiment, the value obtained by adding the predetermined value ΔPB to the filtered full closed intake pressure PBCF after filtering and the intake pipe pressure Pb are compared. The value obtained by adding ΔKC and the parameter KR may be determined.

Embodiment 12 FIG. Next, the learning value KL is maintained until a predetermined time elapses after the detection of the transient state of the engine 1.
In the twelfth embodiment of the present invention in which the learning of the learning value KL is prevented by prohibiting the learning of
4) is described.

In this case, the control device 20 includes a rotation speed change detecting means for detecting that the change in the engine speed Ne is equal to or more than a predetermined value, and a timer means for operating for a predetermined period after detecting the change in the engine speed. And a learning value calculating means for storing, as a learning value, a representative value obtained by performing a time-series operation on the parameter when the timer means is not operating.

The operation of the twelfth embodiment of the present invention will be described below with reference to the timing chart of FIG. Here, the engine transient state refers to a case where the rotation fluctuation of the engine speed Ne is equal to or more than a predetermined value, or a case where the fluctuation of the bypass air flow rate QBYPS is equal to or more than a predetermined value.

For example, in the sixth embodiment, the fully closed intake pressure is predicted from the engine speed Ne and the bypass air flow rate QBYPS, but as described above, the response delay of the pressure sensor 14 and the internal Interface circuit 1
01 to 104, the detected value P of the intake pipe pressure
b lags behind the actual intake pipe pressure change. Therefore, the detected value Pb of the intake pipe pressure is temporally delayed with respect to the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure value PBH obtained according to the change in the engine speed Ne.

As a result, as described in the seventh embodiment, for example, as shown in FIG. 25, when the engine speed Ne suddenly decreases due to braking or the like, the low-land fully closed intake pressure value P
The increase in the intake pipe pressure Pb (dashed line) is delayed with respect to the increase in the BL and the highland fully closed intake pressure value PBH (solid line). Therefore, the parameter KR obtained by the above equation (3)
(Solid line) temporarily drops below the normal value,
The learning value KL (dashed line) also decreases and does not return to the normal value for a while. Therefore, there occurs a problem that the closed state of the throttle valve 4 cannot be detected.

Therefore, in the twelfth embodiment of the present invention, the period (for example, for 1 second) until the intake pipe pressure Pb becomes stable after detecting that the change in the engine speed Ne is equal to or more than a predetermined value, The calculation of the learning value KL is prohibited. Accordingly, even when the engine speed Ne total閉吸air pressure Pb decreases rapidly increases suddenly, the decrease of the learning value KL as shown in dashed line in FIG. 25 KL '(dashed line) as Thus, the closed state of the throttle valve 4 can be accurately detected.

Hereinafter, the operation of the twelfth embodiment of the present invention will be specifically described with reference to the flowcharts of FIGS. 26 and 27. 26 and 27, S701, S740, S730 to S734, and S7
Steps 06 to S714 are the same as those in FIG.
760 to S768 are an additionally inserted engine speed initialization step, timer processing step, and engine speed detection step.

First, when it is determined in step S701 in FIG. 26 that the start flag = 0, in step S740, the learning value initial value KLINI corresponding to the atmospheric pressure value Pa is set.
T (Pa) is stored in the RAM 205.

Subsequently, the flow advances to step S760 to initialize a timer counter TM for inhibiting learning value calculation to zero.
In step S761, the current engine speed Ne is stored in the engine speed Neb 100 ms before in order to initialize the engine speed Neb 100 msec earlier.

If it is determined in step S701 that the start flag = 1, and after the processing in step S761, execution proceeds to air conditioner determination step S730. Hereinafter, in steps S730 to S734 and S705, the bypass air flow rate Q according to the ON / OFF of the air conditioner switch 12 is set.
The parameter KR is calculated in consideration of BYPS.

Next, in step S762, 100
It is determined whether or not the timing is every ms, and if it is the timing every 100 ms (ie, YES), step S763
Then, the timer counter TM for inhibiting the learning value calculation is decremented by one. However, it is assumed that the minimum value (min) of the timer counter TM is limited to 0.

Subsequently, in step S764, a difference between the current engine speed Ne and the engine speed Neb 100 ms before is obtained, and this is set as a speed difference ΔNe as R
Store it in the AM 205. In addition, as a preparation for obtaining a similar rotational speed deviation ΔNe after the next 100 ms, in step S765, the current engine rotational speed Ne is increased by 100.
The value is stored in the engine speed Neb ms before.

Next, in step S766, it is determined whether or not the absolute value | ΔNe | of the rotational speed deviation ΔNe is equal to or greater than a predetermined value DNDEC. If | ΔNe | ≧ DNDEC (that is, YES), the flow proceeds to step S767. Then, a value "10" representing 1 sec is set to the timer counter TM for inhibiting the learning value calculation.

If it is determined in step S762 that the timing is not a timing every 100 ms (ie, NO),
Alternatively, in step S767, | ΔNe | <DND
When it is determined to be EC (that is, NO), and after the process of step S767 is completed, the process proceeds to step S768 (see FIG. 27).

By the processing of steps S762 to S767, the timer counter TM for inhibiting the learning value calculation is set to |
When ΔNe | ≧ DDEC (step S766), an initial value “10” is set (step S76).
7) Then, it is decremented by 1 every 100 ms, and becomes 0 after 1 sec (see FIG. 25).

In step S768 in FIG.
It is determined whether the timer counter TM for inhibiting the learning value calculation is 0 or not. If TM = 0 (that is, YES), 100 ms
It is determined that one second or more has elapsed after the rotation speed deviation ΔNe between the predetermined values DNDEC or more has reached the predetermined value DNDEC, and the process proceeds to learning value calculation steps S706 to S710.

On the other hand, in step S768, TM ≠
When it is determined to be 0 (that is, NO), the processing of the learning value calculation steps S706 to S710 is omitted, and the process proceeds to the calculation step S711 of the predicted fully closed intake pressure value PBC. Hereinafter, after setting or resetting the valve closing flag in steps S712 to S714, the process returns to the processing in FIG.

Embodiment 13 FIG. In the twelfth embodiment, the timer counter TM is set based on the variation ΔNe of the engine speed Ne. However, as in the following thirteenth embodiment (corresponding to claim 15), the variation ΔΔ of the bypass air flow rate QBYPS is set.
The timer counter TM may be set based on QB.

In this case, the control device 20 includes an air flow rate change detecting means for detecting that the change ΔQB of the bypass air flow rate QBYPS is equal to or more than a predetermined value, and a timer means for operating for a predetermined period after detecting the change in the bypass air flow rate. And learning value calculation means for storing a representative value obtained by performing time-series calculation processing of the parameter KR as a learning value KL when the timer means is not operating.

For example, in the case of the twelfth embodiment, since the change in the bypass air flow rate QBYPS is not taken into consideration, the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure obtained in response to the change in the bypass air flow rate QBYPS are considered. The detected value Pb of the intake pipe pressure is temporally delayed from the value PBH.

As a result, for example, as shown in FIG.
When the bypass air flow rate QBYPS is rapidly increased by turning on the air conditioner from off to on, the intake pipe pressure Pb (dotted line) corresponds to an increase in the lowland fully closed intake pressure value PBL and the highland fully closed intake pressure value PBH (solid line). Increase is delayed.

Therefore, as described above, the parameter KR (solid line) obtained by the above equation (3) temporarily drops below the normal value, and the learning value KL (dot-dash line) also drops.
For a while, the throttle valve 4 does not return to the normal value, and the closed state of the throttle valve 4 cannot be detected.

Next, the operation of Embodiment 13 of the present invention will be described with reference to the timing chart of FIG. In this case, the change ΔQ of the bypass air flow rate QBYPS
After detecting that B is equal to or greater than the predetermined value DQBYPS,
A period until the intake pipe pressure Pb is stabilized (for example, 1 sec.
During c), the calculation of the learning value KL is prohibited.

As a result, the bypass air flow rate QBYPS
28, the decrease in the learning value KL as indicated by the one-dot chain line in FIG.
L ′ (broken line) can be prevented. Therefore, the closed state of the throttle valve 4 can be accurately detected. The other points are exactly the same as those of the twelfth embodiment, and the description thereof is omitted.

Next, the above-mentioned operation according to Embodiment 13 of the present invention will be specifically described with reference to the flowchart in FIG. In FIG. 29, S701 and S74
0, S760, S730-S734, S705, S76
26, S763 and S767 are the same steps as in FIG. 26, and S769 to S772 are the bypass air flow initialization step and the timer processing step corresponding to steps S761 and S764 to S766 in FIG. 26, respectively.

[0279] The steps after S768 are as follows.
The illustration is omitted because it is the same as FIG. The description of the same processing steps as those in FIGS. 26 and 27 is omitted.

First, in the same manner as described above, if it is determined in step S701 that the start flag = 0, the learning value K is determined in steps S740 and S760.
After initializing L and the timer counter TM for inhibiting the learning value calculation, the process proceeds to a bypass air flow rate initialization step S769.

In step S769, 100 ms
The current bypass air flow rate QBYPSB is stored as the air flow rate QBYPSB 100 ms before to initialize the bypass air flow rate QBYPSB 100 ms before used to detect the change ΔQB in the bypass air flow rate during the period.

The following steps S730 to S730 are the same as those described above.
Through steps 734, S705, S762, and S763, the process proceeds to step S770 for calculating the bypass air flow deviation ΔQB, and the difference (change amount) between the current bypass air flow QBYPS and the bypass air flow QBYPSB 100 ms before is obtained. The deviation ΔQB is stored in the RAM 205.

In step S771, 100 m
As a preparation for obtaining the same bypass air flow deviation ΔQB after s, the current bypass air flow QBYPS is set to 1
It is stored as the bypass air flow rate QBYPSB 00 ms before.

Subsequently, in step S772, the absolute value | ΔQB | of the bypass air flow rate deviation ΔQB is set to a predetermined value D.
It is determined whether QBYPS or more is satisfied, and | ΔQB | ≧ DQBY
If it is determined to be PS (ie, YES), the process proceeds to step S767, where the timer counter T for inhibiting the learning value calculation is set.
A numerical value “10” representing 1 sec is set in M.

If it is determined in step S762 that the timing is not the timing of every 100 ms (ie, NO),
Alternatively, in step S772, | ΔQB | <DQB
If YPS (that is, NO) is determined, and after the process of step S767 is completed, step S768 (FIG.
7).

The above steps S762, S763, S7
By the processing of 70 to S772 and S767, the timer counter TM for inhibiting the learning value calculation becomes | ΔQB | ≧ DQBY
When the value reaches PS (step S772), the initial value “1” is set.
"0" is set (step S767), and then 10
It is decremented by 1 every 0 ms, and 0 after 1 sec.
(See FIG. 28).

After proceeding to step S768, the first embodiment
As in step 2, the processing in steps S768 to S714 (FIG. 27) is executed, and the process returns to the processing in FIG.

Embodiment 14 FIG. In the twelfth and thirteenth embodiments, the parameter KR is calculated using the lowland fully closed intake pressure PBL and the highland fully closed intake pressure PBH. However, as in the above-described second embodiment, the lowland fully closed intake pressure is calculated. The difference between the PBL and the highland fully closed intake pressure PBH may be stored in the ROM 206 in advance as the fully closed intake pressure deviation ΔP, and used for calculating the parameter KR.

Embodiment 15 FIG. In the twelfth and thirteenth embodiments, the value obtained by adding the predetermined value ΔPB to the predicted fully closed intake pressure PBC is compared with the intake pipe pressure Pb. The value obtained by adding the predetermined value ΔKC to KL may be compared with the parameter KR.

Embodiment 16 FIG. Also, for example, in the thirteenth embodiment,
In the above, the air flow rate for the air conditioner was calculated as a standard value. However, if the actual air flow rate for the air conditioner does not match the standard value, the learning value KL may be erroneously learned. Paying attention to the fact that there is no change in the atmospheric pressure immediately after, as in the following embodiment 16 (corresponding to claim 16 and claim 17), the update of the learning value KL may be prohibited for a predetermined period after the air conditioner is turned on. .

In this case, the control device 20 determines whether or not the bypass air flow rate QBYPS
, A timer that operates for a predetermined period of time after the air conditioner load changes from off to on, and a timer KL that prohibits updating of the learning value KL while the timer is operating. A bypass air flow rate correcting means for correcting the bypass air flow rate QBYPS so as to match the value KL.

The bypass air flow rate correction means corrects the bypass air flow rate so that the parameter matches the learned value when the parameter is smaller than the learned value, and when the parameter is greater than the learned value and smaller than the predetermined value. Gradually increase bypass air flow.

For example, in the thirteenth embodiment, FIG.
9, the air flow rate QBYPS in the bypass intake passage 6 that bypasses the throttle valve 4 of the engine 1 when the air conditioner switch 12 is turned off, based on the following equation (18). When the switch 12 is on, the estimation calculation is performed based on the following equation (19).

QBYPS = QFIA (WT) + QISC (18) QBYPS = QFIA (WT) + QISC + QAC (19)

In the equations (18) and (19), QFIA (WT) is the FIA air flow rate previously stored in the ROM 206 in accordance with the cooling water temperature value WT (FIG. 12).
), QISC is the ISC air flow rate obtained in step S9 in FIG. 3, and QAC is RO
This is the air flow rate for the air conditioner corresponding to the standard air flow rate of the air conditioner bypass passage 9 stored in M206.

As described above, in the thirteenth embodiment,
Although the bypass air flow rate QBYPS is estimated and calculated according to the cooling water temperature value WT and the state of the air conditioner switch 12, the air flow rate QAC for the air conditioner added when the air conditioner switch 12 is turned on is equal to the standard air flow rate QAC of the bypass path 9 for the air conditioner. This is a value equivalent to a typical air flow rate.

Therefore, the air flow rate of the ACIUS valve 11 is manually adjusted in the increasing direction in summer when the air conditioner load is heavier than the standard,
When the air flow rate of the IUS valve 11 is manually adjusted in the decreasing direction, the air flow rate of the air conditioner bypass passage 9 does not always match the standard air conditioner air flow rate QAC.

For example, when the air flow rate in the air conditioner bypass passage 9 is smaller than the standard air conditioner air flow rate QAC, as shown in FIG. 30, the intake pipe pressure Pb (dashed line) indicates that the air conditioner switch 12 is turned on. Sometimes, the air flow rate in the air conditioner bypass passage 9 is smaller than in the standard case .

As a result, the parameter KR obtained by the above equation (11) is lower than when the air conditioner switch 12 is off, and the learning value KL is also lower.
The learning value KL does not return to the normal value for a while after the air conditioner switch 12 is turned off from the on state as shown by the one-dot chain line in FIG. Therefore, there is a problem that the closed state of the throttle valve cannot be detected.

If the air flow rate in the air conditioner bypass passage 9 is larger than the standard air conditioner air flow rate QAC,
As shown in FIG. 31, when the air conditioner switch 12 is turned on, the intake pipe pressure Pb becomes larger than when the air flow rate in the air conditioner bypass passage 9 is standard.

As a result, the parameter KR obtained by the above equation (11) is larger than when the air conditioner switch 12 is off. However, it takes a while for the learning value KL (dashed-dotted line in FIG. 31) to reach the parameter KR (solid line) at that time. Therefore, after the air conditioner switch 12 is turned on from off, the throttle is used for a while. There is a problem that the closed state of the valve cannot be detected.

Therefore, in the sixteenth embodiment of the present invention, when the air conditioner switch 12 changes from off to on, there is no change in the atmospheric pressure immediately before and after the switch 12 is turned on. Focusing on the fact that KL does not change, updating of the learning value KL is prohibited for a predetermined period (for example, for 60 seconds) after the air conditioner switch 12 changes from off to on, and conversely, the parameter KR matches the learning value KL. Thus, the air flow rate QAC for the air conditioner is corrected.

Hereinafter, the operation of the sixteenth embodiment of the present invention will be described with reference to the timing charts of FIGS. 32 and 33. First, after the air conditioner switch 12 is turned on from off, if the parameter KR for a predetermined period is smaller than the learning value KL, the parameter KR matches the learning value KL based on the following equation (20). Of the bypass air flow rate QBYPS 'is obtained.

QBYPS ′ = [256 × [Pb − {(1-KL) × PBHZ (Ne) + KL × PBLZ (Ne)}]] / [｛(1-KL) × PBHF (Ne) + KL × PB LF ( Ne)｝-｛(1-KL) × PBHZ (Ne) + KL × PBLZ (Ne)｝] ... (20)

Also, based on the bypass air flow rate QBYPS 'calculated by the equation (20) and the bypass air flow rate QBYPS already calculated by the above equation (19), based on the following equation (21), Flow rate QAC to Q
It is corrected to AC '(part C in FIG. 32).

QAC ′ = QAC− (QBYPS−QBYPS ′) (21)

On the other hand, if the parameter KR for a predetermined period is larger than the learning value KL after the air conditioner switch 12 is turned on from off to on, whether it is due to an error in the air conditioner air flow rate QAC, or It cannot be determined whether the throttle valve 4 is slightly opened or not.

However, it is determined whether or not the parameter KR is smaller than a predetermined value (for example, 1.2). If the parameter KR is smaller than the predetermined value, the vehicle is in a deceleration state and the throttle valve 4 is not operated. Since there is a possibility that the air conditioner may be fully closed, it is determined that the error may be caused by an error in the air conditioner air flow rate QAC. Therefore, in order to prevent erroneous learning of the learning value KL, the air flow rate QAC for the air conditioner is gradually increased so that the parameter KR matches the learning value KL (portion D in FIG. 33).

With the above processing, the air flow rate Q for the air conditioner
Erroneous detection of the learning value KL due to an AC error can be prevented. Further, although the change in the fully closed intake pressure due to the change in the atmospheric pressure Pa and the change in the fully closed intake pressure due to the change in the bypass air flow rate QBYPS are not completely the same, both of the learning value KL and the air flow rate QAC for the air conditioner indicate the change. , Can be independently corrected, so that the fully closed intake pressure can be more accurately predicted.

Next, the above-mentioned operation according to the sixteenth embodiment of the present invention will be described in detail with reference to the flowcharts of FIGS. 34 and 35, S701, S740, S760, S730 to S73.
4 and S705 to S714 are the same steps as those in FIGS. 27 and 29, and S780 to S789 are an air-conditioner air flow initialization step additionally inserted, a timer processing step, and a learning value update prohibition step.

The description of the same processing steps as described above will be omitted. First, in the same manner as described above, if it is determined in step S701 that the start flag = 0, in steps S740 and S760, the learning value KL and the timer counter TM for inhibiting learning value calculation are initialized, and Proceeding to an air flow rate initialization step S780, an initial value QACINI is stored as the air conditioner air flow rate QAC.

Hereinafter, steps S730 to S730 similar to those described above are performed.
Through steps 734, S705, S762, and S763, the parameter KR is calculated, and the timer counter TM is decremented by 1 at a timing of 100 ms. If it is determined in step S762 that the timing is not 100 ms, or after the processing in step S763, the process proceeds to step S781.

In step S781, it is determined whether the air conditioner switch 12 is on or not, and
If NO), the process proceeds to step S782,
The value “60” corresponding to 60 seconds is stored in the timer counter TM.
Set "0". In step S781, when it is determined that the air conditioner switch 12 is turned on (that is, YES), and after the process of step S782 is completed, step S7 is performed.
Go to 83.

The above steps S762, S763, S7
According to 81 and S782, 60 seconds after the air conditioner switch 12 is turned on and turned on from off.
When the above has elapsed, the timer counter TM becomes 0 (see FIGS. 32 and 33).

In step S783, it is determined whether or not the air conditioner switch 12 is on, and if not, the air conditioner switch 12 is not on (ie,
If the determination is NO, the flow proceeds to step S706 (see FIG. 35), and if it is determined that the air conditioner switch 12 is ON (that is, YES), the flow proceeds to step S768.

If it is determined in step S768 that the timer counter TM is 0 (ie, YES), it is determined that at least a predetermined time (60 seconds) has elapsed after the air conditioner switch was turned on from off, and the flow proceeds to step S7.
Proceeding to step 06, after executing the above-described steps S706 to S714, the process returns to the processing in FIG.

On the other hand, when it is determined in step S768 that the timer counter TM is not equal to 0 (that is, NO),
6 after the air conditioner switch 12 changes from off to on
It is determined that the time is within 0 seconds, and step S784 (FIG. 3)
5). Steps S784, S787, and S788 are the same as steps S706, S708, and S788 described above.
709.

In step S784, it is determined whether or not the parameter KR is smaller than the learning value KL.
If L (that is, YES) is determined, step S7
85, and based on the above equation (20), the parameter K
Bypass air flow rate QB for R to match learning value KL
Find YPS '.

In step S786, using the bypass air flow rate QBYPS 'and the bypass air flow rate QBYPS calculated in step S732 (see FIG. 34), the air flow rate for air conditioner obtained based on the above equation (21). The air flow rate QAC for the air conditioner is corrected by the QAC '(part C in FIG. 32), and the process proceeds to step S711.

On the other hand, in step S784, KR ≧
If determined as KL (that is, NO), step S7
Proceeding to 87, it is determined whether the parameter KR is smaller than a predetermined value 1.2. If KR <1.2 (that is, YE
If determined to be S), the process proceeds to step S788, where 10
It is determined whether or not the timing is every 0 ms. If the timing is every 100 ms, the process proceeds to step S789.

In step S789, a predetermined value ΔQAC is added to the air flow rate QAC for air conditioner to update the air flow rate QAC for air conditioner (part D in FIG. 33), and the flow advances to step S711.

On the other hand, in step S787, KR ≧
When it is determined to be 1.2 (that is, NO), or when it is determined that the timing is not the timing of every 100 ms (that is, NO) in step S788, the process proceeds to step S711 without updating the learning value KL.

Embodiment 17 FIG. In the sixteenth embodiment, in order to calculate the parameter KR, the lowland fully closed intake pressure PB
L and the high altitude fully closed intake pressure PBH were used, but the difference between the low altitude fully closed intake pressure PBL and the high altitude fully closed intake pressure PBH was previously defined as the fully closed intake pressure deviation ΔP as in the second embodiment.
It may be stored in the OM 206.

Embodiment 18 FIG. In the sixteenth embodiment, a value obtained by adding a predetermined value ΔPB to the predicted fully-closed intake pressure PBC,
Although the intake pipe pressure Pb is compared, the value obtained by adding the predetermined value ΔKC to the learning value KL may be compared with the parameter KR as in the sixth embodiment.

[0325]

As described above, according to the first aspect of the present invention, the engine speed calculating means for calculating the engine speed corresponding to the driving timing of the engine, and the pressure detecting means for detecting the intake pipe pressure of the engine. Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state, at least according to the engine speed; Parameter calculation means for calculating a parameter representing the relationship of the intake pipe pressure to the pressure value; learning value calculation means for storing a representative value obtained by performing a time-series calculation of the parameter as a learning value; Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the first and second pressure values; The throttle valve closed state detecting means for judging that the throttle valve is closed at the time is provided, so that the open / closed state of the throttle valve can be detected without using a throttle opening sensor or an idle switch. There is an effect that an engine control throttle valve open / closed state detecting device that realizes down is obtained.

According to a second aspect of the present invention, in the first aspect, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is defined as a second pressure value, and the parameter calculation means determines the intake pipe pressure and the first pressure value with respect to the difference between the second pressure value and the first pressure value. The learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value, and stores the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. The pressure estimation value calculating means multiplies the difference between the second pressure value and the first pressure value by a learning value, and further adds a first pressure value as a pressure estimation value. The throttle valve closed state detecting means detects that the intake pipe pressure is The throttle valve is determined to be closed when the value is smaller than a value obtained by adding a predetermined value to the value, so that the open / close state of the throttle valve can be detected without using a throttle opening sensor or an idle switch. Thus, there is an effect that an engine control throttle valve open / closed state detecting device which can realize cost reduction can be obtained.

According to a third aspect of the present invention, in the first aspect, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, The difference between the value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude and the first pressure value is defined as a second pressure value, and the parameter calculation means determines the intake pipe pressure and the first pressure value with respect to the second pressure value. The learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value, and stores the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. The pressure estimation value calculation means multiplies the second pressure value by the learning value, and further adds the first pressure value to obtain a pressure estimation value. The throttle valve closed state detection means Intake pipe pressure adds predetermined value to pressure estimate It is determined that the throttle valve is in the closed state when the value is smaller than the set value.This simplifies the calculation and detects the open / closed state of the throttle valve without using a throttle opening sensor or idle switch. Thus, there is an effect that an engine control throttle valve open / closed state detection device which realizes cost reduction can be obtained.

According to a fourth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to the driving timing of the engine, a pressure detecting means for detecting an intake pipe pressure of the engine, A bypass intake passage for bypassing the throttle valve, bypass air flow rate calculating means for estimating and calculating a bypass air flow rate in the bypass intake passage, and an intake pipe when the throttle valve is in a closed state according to at least the engine speed and the bypass air flow rate Pressure value calculating means for calculating first and second pressure values related to pressure; parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculating means for storing a representative value obtained by performing an arithmetic processing as a learning value, a learning value, a first pressure value and a second pressure value, Pressure estimation value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the throttle valve, and the throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. The throttle valve closed state detection means that determines whether the throttle valve is closed eliminates the need for a throttle opening sensor and idle switch, thereby realizing cost reduction and accurately detecting the open / closed state of the throttle valve regardless of the bypass air flow rate. There is an effect that a throttle valve open / closed state detecting device for engine control that can be obtained is obtained.

According to a fifth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing, a pressure detecting means for detecting an intake pipe pressure of the engine, Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve is closed according to the number of revolutions, and a relationship between the intake pipe pressure and the first and second pressure values Parameter calculation means for calculating a parameter representing the parameter, learning value calculation means for storing, as a learning value, a representative value obtained by processing the parameters in time series, atmospheric pressure detection means for detecting atmospheric pressure, Learning value initial value calculating means for calculating an initial value of the learning value based on the atmospheric pressure; and pressure estimation of the intake pipe when the throttle valve is closed based on the learning value and the first and second pressure values. And a throttle valve closed state detecting means for determining that the throttle valve is closed when the intake pipe pressure is smaller than the pressure estimated value in a predetermined relationship. There is an effect that an engine control throttle valve open / closed state detection device that can accurately detect the open / closed state of the throttle valve immediately after the start of the engine while achieving cost reduction by eliminating the need for an opening sensor and an idle switch.

According to a sixth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to a driving timing of the engine, a pressure detecting means for detecting an intake pipe pressure of the engine, Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state according to the number of revolutions; and intake air for the first and second pressure values. Parameter calculation means for calculating a parameter representing the relationship between pipe pressures; learning value calculation means for storing a representative value obtained by performing a time-series calculation on the parameter as a learning value; The throttle valve closed state detecting means for judging that the throttle valve is closed when it is small is provided, so that the calculation is simplified and the throttle opening degree And idle switch engine control throttle valve opening and closing state detecting device that achieves cost as unnecessary and there is the effect obtained.

According to a seventh aspect of the present invention, in the sixth aspect, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is defined as a second pressure value, and the parameter calculation means determines the intake pipe pressure and the first pressure value with respect to the difference between the second pressure value and the first pressure value. The learning value calculation means stores the parameter as a learning value when the parameter is smaller than the learning value, and stores the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. The throttle valve closed state detecting means determines that the throttle valve is in the closed state when the parameter is smaller than a value obtained by adding a predetermined value to the learning value, so that the calculation is simplified. And at the same time Liter opening sensor and idle switch engine control throttle valve opening and closing state detecting device that achieves cost down as unnecessary there is the effect obtained.

According to the present invention, the engine speed calculating means for calculating the engine speed corresponding to the driving timing of the engine, the pressure detecting means for detecting the intake pipe pressure of the engine, and at least the engine Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state in accordance with the number of revolutions, and a filter for the first and second pressure values Filtered pressure value calculation means for performing processing to calculate first and second filtered pressure values, and parameter calculation means for calculating a parameter representing the relationship between the first and second filtered pressure values and the intake pipe pressure Learning value calculating means for storing, as a learning value, a representative value obtained by arithmetically processing parameters in a time series; and a throttle based on the learning value and the first and second pressure values. Pressure estimation value calculating means for calculating an estimated value of the intake pipe pressure when the intake valve is closed, and a throttle for determining that the throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. A valve closing state detecting means eliminates the need for a throttle opening sensor and an idle switch, thereby realizing cost reduction, and an engine control capable of accurately detecting the opening / closing state of the throttle valve even when the engine state changes suddenly. This has the effect of obtaining a throttle valve opening / closing state detecting device for use.

According to claim 9 of the present invention, in claim 8, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as a second pressure value, and the filtered pressure value calculation means performs a primary low-pass filter process on the first and second pressure values. The first and second filtered pressure values are obtained, and the parameter calculating means calculates the intake pipe pressure and the first filtered pressure value with respect to the difference between the second filtered pressure value and the first filtered pressure value. The learning value calculation means stores the parameter as the learning value when the parameter is smaller than the learning value, and gradually increases the learning value when the parameter is equal to or larger than the learning value and smaller than the predetermined value. Memorize and calculate pressure estimate Multiplies the difference between the second pressure value and the first pressure value by a learning value, and further adds the first pressure value to obtain a pressure estimated value. The throttle valve is determined to be closed when the pressure is smaller than a value obtained by adding a predetermined value to the pressure estimation value. Thus, there is an effect that an engine control throttle valve open / closed state detecting device capable of accurately detecting the open / closed state of the throttle valve even if the value suddenly changes is obtained.

According to a tenth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to an engine driving timing, a pressure detecting means for detecting an intake pipe pressure of the engine, Pressure value calculation means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state according to the rotational speed; and a throttle valve based on the first pressure value. A first filtered pressure value calculating means for filtering the first pressure value to calculate a first filtered pressure value only when it is determined that the intake pipe pressure in the closed state is in the increasing direction; Only when it is determined based on the second pressure value that the intake pipe pressure when the throttle valve is closed is in the increasing direction, the second pressure value is filtered to calculate the second filtered pressure value. Do A pressure calculating means after second filter,
Parameter calculation means for calculating a parameter representing the relationship between the first and second filtered pressure values and the intake pipe pressure, and a learning value for storing a representative value obtained by performing a time-series calculation of the parameter as a learning value Calculation means; pressure estimation value calculation means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the learned value and the first and second pressure values; A throttle valve closed state detecting means for judging that the throttle valve is closed when it is small in a predetermined relationship with respect to the throttle valve. A throttle valve open / closed state detector for engine control that can accurately detect the open / closed state of the throttle valve even when the intake pipe pressure suddenly changes when the valve is closed. There is an effect to be.

According to claim 11 of the present invention, in claim 10, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as a second pressure value, and the first filtered pressure value calculating means determines that the first pressure value is smaller than the first filtered pressure value. Only when the pressure value is large, the first pressure value is subjected to a first-order low-pass filtering process to obtain a first filtered pressure value,
The filtered pressure value calculating means performs the first low-pass filtering process on the second pressure value only when the second pressure value is larger than the second filtered pressure value, The parameter calculation means uses the ratio of the difference between the intake pipe pressure and the first filtered pressure value to the difference between the second filtered pressure value and the first filtered pressure value as a parameter, The calculating means stores the parameter as a learning value when the parameter is smaller than the learning value, and gradually increases and stores the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. Multiplying a difference between the second pressure value and the first pressure value by a learning value;
The throttle valve closed state detecting means determines that the throttle valve is in the closed state when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. This eliminates the need for a throttle opening sensor and idle switch to achieve cost reduction, and accurately detects the open / closed state of the throttle valve even when the intake pipe pressure suddenly changes when the throttle valve is closed. There is an effect that a throttle valve open / closed state detecting device for engine control that can be obtained is obtained.

According to a twelfth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing, a pressure detecting means for detecting an intake pipe pressure of the engine, and at least the engine Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state according to the number of revolutions; and intake air for the first and second pressure values. Parameter calculation means for calculating a parameter representing the relationship between pipe pressures, learning value calculation means for storing a representative value obtained by performing a time-series calculation on the parameter as a learning value, and a learning value and first and second learning values. Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the pressure value, and determining that the pressure estimated value is in a decreasing direction based on the pressure estimated value. Only when the pressure estimation value is filtered and the filtered pressure estimation value calculating means for calculating the filtered pressure estimation value, and when the intake pipe pressure is smaller than the filtered pressure estimation value in a predetermined relationship. A throttle valve closed state detecting means for determining that the throttle valve is closed is provided, so that a throttle opening sensor and an idle switch are not required to realize a cost reduction and an intake pipe when the throttle valve is closed. There is an effect that an engine control throttle valve open / closed state detecting device capable of accurately and stably detecting the closed state of the throttle valve even when the pressure suddenly decreases is obtained.

According to a thirteenth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to an engine drive timing, a pressure detecting means for detecting an intake pipe pressure of the engine, Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when the throttle valve in the intake pipe is in a closed state according to the number of revolutions; and intake air for the first and second pressure values. Parameter calculation means for calculating a parameter representing the relationship between pipe pressures, rotation speed change detection means for detecting that the change in engine speed is greater than or equal to a predetermined value, and rotation speed change detection means for detecting a change in engine speed Timer means that operates for a predetermined period of time after that, and a representative value obtained by performing time-series arithmetic processing of parameters when the timer means is not operating is stored as a learning value. A learning value computing means that the learning value and the first
Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is closed based on the second pressure value and the second pressure value, and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. A throttle valve closed state detecting means for determining that the throttle valve is closed is provided, so that a throttle opening sensor and an idle switch are not required to realize a cost reduction, and a throttle valve is provided irrespective of a change in the engine speed. There is an effect that an engine control throttle valve open / closed state detecting device capable of accurately detecting the open / closed state of the valve can be obtained.

According to a fourteenth aspect of the present invention, in the thirteenth aspect, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as a second pressure value,
The ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is used as a parameter, and the learning value calculation means sets the parameter when the parameter is smaller than the learning value. When the parameter is greater than or equal to the learning value and smaller than the predetermined value, the learning value is gradually increased and stored. The pressure estimation value calculating means calculates a difference between the second pressure value and the first pressure value. A value obtained by multiplying the learned value and further adding the first pressure value is used as a pressure estimated value. When the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimated value, the throttle valve closed state detecting means detects the throttle valve closed state. Since the valve is determined to be closed, the cost is reduced by eliminating the need for a throttle opening sensor and idle switch, and the open / closed state of the throttle valve is accurately detected regardless of the change in the engine speed. It is effective that the resulting throttle valve opening state detection device for the engine control that can.

According to a fifteenth aspect of the present invention, the engine speed calculating means for calculating the engine speed corresponding to the driving timing of the engine, the pressure detecting means for detecting the intake pipe pressure of the engine, A bypass intake passage for bypassing the throttle valve, bypass air flow rate calculating means for estimating and calculating a bypass air flow rate in the bypass intake passage, and an intake pipe when the throttle valve is in a closed state according to at least the engine speed and the bypass air flow rate Pressure value calculating means for calculating first and second pressure values related to pressure; parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values;
Air flow rate change detecting means for detecting that the change in bypass air flow rate is equal to or greater than a predetermined value; timer means for operating for a predetermined period after the air flow rate change detecting means detects a change in bypass air flow rate; and timer means for operating. A learning value calculating means for storing, as a learning value, a representative value obtained by performing a time-series calculation processing of the parameter when the throttle valve is not operated; and closing the throttle valve based on the learning value and the first and second pressure values. Pressure estimated value calculating means for calculating an estimated value of the intake pipe pressure in the state, and a throttle valve for determining that the throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. The provision of the closed state detection means eliminates the need for a throttle opening sensor and idle switch to achieve cost reduction, and allows the throttle to operate regardless of the change in bypass air flow rate. The effect of stabilizing the engine control throttle valve can be detected open or closed state detector close state can be obtained.

According to a sixteenth aspect of the present invention, an engine speed calculating means for calculating an engine speed corresponding to the driving timing of the engine, a pressure detecting means for detecting an intake pipe pressure of the engine, A bypass intake passage for bypassing the throttle valve, a bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage at least according to the presence or absence of an air conditioner load, and a throttle valve at least according to an engine speed and a bypass air flow rate Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure when is closed, and a parameter for calculating a parameter representing the relationship of the intake pipe pressure to the first and second pressure values. A calculating means, and a learning value calculating means for storing, as a learning value, a representative value obtained by processing parameters in a time-series manner. Timer means that operates for a predetermined period after the air conditioner load changes from off to on, and updating of the learning value is prohibited while the timer means is operating, and the bypass air flow rate is corrected so that the parameter matches the learning value. A bypass air flow rate correcting means for calculating, a pressure estimated value calculating means for calculating an intake pipe pressure estimated value when the throttle valve is closed based on the learned value and the first and second pressure values;
Throttle valve closed state detecting means for determining that the throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship is provided, so that a throttle opening sensor and an idle switch are not required. In addition to the cost reduction, an engine control throttle valve open / closed state detection device capable of accurately detecting the open / closed state of the throttle valve regardless of a change in the air-conditioner load bypass air flow rate is obtained.

According to a seventeenth aspect of the present invention, in the sixteenth aspect, the pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as a first pressure value, A value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as a second pressure value,
The ratio of the difference between the intake pipe pressure and the first pressure value to the difference between the second pressure value and the first pressure value is used as a parameter, and the learning value calculation means sets the parameter when the parameter is smaller than the learning value. When the parameter is greater than or equal to the learning value and smaller than the predetermined value, the learning value is gradually increased and stored. When the parameter is smaller than the learning value, the parameter matches the learning value. The bypass air flow rate is corrected so that the parameter is equal to or greater than the learned value and is smaller than the predetermined value, and the bypass air flow rate is gradually increased. The pressure estimation value calculation means calculates the difference between the second pressure value and the first pressure value. A value obtained by multiplying the difference by a learning value and further adding a first pressure value is used as a pressure estimated value. When the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimated value, To Since the throttle valve is determined to be in the closed state, the cost is reduced by eliminating the need for a throttle opening sensor and idle switch, and the open / closed state of the throttle valve is accurately determined regardless of changes in the bypass air flow rate for the air conditioner load. Thus, there is an effect that an engine control throttle valve open / closed state detection device that can detect the throttle valve opening / closing state can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing an entire engine control device to which a first embodiment of the present invention is applied;

FIG. 2 is a block diagram showing an internal configuration of a control device in FIG.

FIG. 3 is a flowchart illustrating a schematic operation of the engine control device of FIG. 1;

FIG. 4 is a flowchart showing a processing routine of an idle speed control step in FIG. 3;

FIG. 5 is a flowchart showing a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to the first embodiment of the present invention.

FIG. 6 is a flowchart showing a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to the second embodiment of the present invention.

FIG. 7 is a flowchart showing a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 3 of the present invention.

FIG. 8 is a flowchart showing a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 4 of the present invention.

FIG. 9 is a map characteristic diagram showing a relationship between a deviation ΔN between target rotation speed data and actual rotation speed data and a control gain KI used in each embodiment of the present invention.

FIG. 10 is a map characteristic diagram showing a relationship between a duty ratio of a drive signal and an ISC air flow rate QSSC used in each embodiment of the present invention.

11 is an explanatory diagram showing a duty ratio of a drive signal in FIG.

FIG. 12 is a map characteristic diagram showing a relationship between a cooling water temperature value WT and an FIA air flow rate QFIA used in each embodiment of the present invention.

FIG. 13 is a map characteristic diagram showing a relationship between an engine speed Ne, a fully closed intake pressure, and an intake pipe pressure Pb used in each embodiment of the present invention.

FIG. 14 is a timing chart showing a throttle valve open / closed state detection operation according to each embodiment of the present invention.

FIG. 15 is a map characteristic diagram showing a relationship among an engine speed Ne, a bypass air flow rate QBYPS, and a fully closed intake pressure Pb used in Embodiment 3 of the present invention.

FIG. 16 shows an atmospheric pressure Pa used in Embodiment 4 of the present invention.
FIG. 9 is a map characteristic diagram showing a relationship between a learning value and an initial value KLINIT (Pa) of a learning value.

FIG. 17 is a flowchart showing a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 6 of the present invention.

FIG. 18 is a timing chart showing an operation when the engine speed is rapidly decreased according to a seventh embodiment of the present invention.

FIG. 19 is a timing chart showing an operation when a bypass air flow rate is rapidly increased according to a seventh embodiment of the present invention.

20 is a flowchart showing a processing routine of a throttle valve open / closed state detection step in FIG. 3 according to Embodiment 7 of the present invention.

FIG. 21 is a timing chart showing an operation at the time of a rapid decrease in bypass air flow rate according to Embodiment 8 of the present invention.

FIG. 22 is a flowchart showing a main part of a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 8 of the present invention.

FIG. 23 is a timing chart showing an operation when a bypass air flow rate is sharply reduced according to a ninth embodiment of the present invention.

FIG. 24 is a flowchart showing a main part of a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to the ninth embodiment of the present invention.

FIG. 25 is a timing chart showing an operation when the engine speed is rapidly decreased according to a twelfth embodiment of the present invention.

FIG. 26 is a flowchart showing a first half of a processing routine of a throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 12 of the present invention;

FIG. 27 is a flowchart showing the latter half of the processing routine of the throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 12 of the present invention;

FIG. 28 is a timing chart showing an operation when a bypass air flow rate is rapidly increased according to Embodiment 13 of the present invention.

FIG. 29 is a flowchart showing a main part of a processing routine of a throttle valve open / closed state detection step in FIG. 3 according to Embodiment 13 of the present invention;

FIG. 30 is a timing chart showing an operation at the time of a sudden decrease in bypass air flow when a general air conditioner is shut off.

FIG. 31 is a timing chart showing an operation at the time of a sudden increase in bypass air flow when a general air conditioner is turned on.

FIG. 32 is a timing chart showing an operation at the time of a sharp decrease in bypass air flow rate when an air conditioner is shut off according to Embodiment 16 of the present invention.

FIG. 33 is a timing chart showing an operation when a bypass air flow rate sharply increases when an air conditioner is turned on according to Embodiment 16 of the present invention.

FIG. 34 is a flowchart showing a first half of a processing routine of a throttle valve opening / closing state detecting step in FIG. 3 according to Embodiment 16 of the present invention;

FIG. 35 is a flowchart showing the latter half of the processing routine of the throttle valve open / closed state detecting step in FIG. 3 according to Embodiment 16 of the present invention;

[Explanation of symbols]

Reference Signs List 1 engine 3 intake pipe 4 throttle valve 5 water temperature sensor 6 bypass air passage 6a FIA passage 7 FIA valve 9 air conditioner bypass passage 10 ISC bypass passage 11 ACIUS valve 13 ISC solenoid valve 14 pressure sensor 16 ignition coil 20 control device KR parameter KL learning Value Ne Engine speed Pa Atmospheric pressure Pb Intake pipe pressure PBH Highland fully closed intake pressure (first pressure value) PBL Lowland fully closed intake pressure (second pressure value) ΔP Pressure deviation (second pressure value) PBC prediction Fully-closed intake pressure (estimated pressure value) QBYPS Bypass air flow rate WT Cooling water temperature value S7 Throttle valve open / closed state detection steps S703, S733 Steps of calculating first pressure value PBH S704, S734 Steps of calculating second pressure value PBL S705, S721 , S744 Step of calculating the parameter KR S706 Step of comparing the parameter KR with the learning value KL S708 Step of comparing the parameter KR with a predetermined value S710 Step of gradually increasing the learning value S711, S722 Step of calculating the pressure estimation value PBC S712, S741, S752 Step of judging throttle valve closed state S720 Step of calculating second pressure value ΔP S730, S781 Step of judging air conditioner state S731, S732 Step of calculating bypass air flow rate QBYPS S740 Step S740 sets initial value KLINIT of learning value Step of calculating S742 Step of calculating the first filtered pressure value PBHF S743 Step of calculating the second filtered pressure value PBHL S745, S747 Step of determining a change in the pressure value Steps S746, S748 Steps for inhibiting the filtering process S750, S751 Steps for calculating the estimated pressure value PBCF after filtering S763, S767, S768 Timer steps S764-S766 Steps for detecting a change in the engine speed S770-S772 Step of detecting change S780 Step of initializing air-conditioner air flow rate QAC S782, S783 Timer step S784-S789 Step of prohibiting update of learning value S785 Step of correcting bypass air flow rate

Claims (17)

(57) [Claims] An engine speed calculating means for calculating an engine speed corresponding to a driving timing of the engine; a pressure detecting means for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
Pressure value calculating means for calculating a second pressure value; and parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculation means for storing a representative value obtained by the processing as a learning value; and a pressure in the intake pipe when the throttle valve is closed based on the learning value and the first and second pressure values. Pressure estimated value calculating means for calculating an estimated value; throttle valve closed state detecting means for determining that the throttle valve is closed when the intake pipe pressure is smaller than the pressure estimated value in a predetermined relationship; A throttle valve open / closed state detection device for engine control, comprising: 2. The pressure value calculating means sets a value corresponding to an intake pipe pressure when the throttle valve is closed at high altitude as the first pressure value, and calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude. The corresponding value is set to the second pressure value, and the parameter calculating means calculates a difference between a difference between the intake pipe pressure and the first pressure value with respect to a difference between the second pressure value and the first pressure value. The ratio is the parameter, the learning value calculation means stores the parameter as the learning value when the parameter is smaller than the learning value, and stores the parameter as the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. The learning value is gradually increased and stored. The pressure estimation value calculation means multiplies the difference between the second pressure value and the first pressure value by the learning value,
The throttle valve closed state detecting means is configured to close the throttle valve when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. 2. The engine control throttle valve open / closed state detecting device according to claim 1, wherein the state is determined to be a state. 3. The pressure value calculation means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at high altitude as the first pressure value, and calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude. A deviation between a corresponding value and the first pressure value is defined as a second pressure value, and the parameter calculating means calculates a ratio of a difference between the intake pipe pressure and the first pressure value to the second pressure value. The learning value calculation means stores the parameter as the learning value when the parameter is smaller than the learning value, and stores the learning when the parameter is equal to or more than the learning value and smaller than a predetermined value. The pressure estimation value calculation means multiplies the second pressure value by the learning value and further adds the first pressure value to obtain the pressure estimation value. Valve closed state detection hand 2. The engine control throttle valve according to claim 1, wherein when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the pressure estimation value, the throttle valve is determined to be in a closed state. State detection device. 4. An engine speed calculating means for calculating an engine speed corresponding to a driving timing of the engine; a pressure detecting device for detecting an intake pipe pressure of the engine; and a bypass intake passage for bypassing a throttle valve in the intake pipe. A bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage; and at least an engine speed and a bypass air flow rate related to the intake pipe pressure when the throttle valve is closed according to the bypass air flow rate. Pressure value calculating means for calculating first and second pressure values; parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculating means for storing a representative value obtained by the arithmetic processing as a learning value; Pressure estimation value calculating means for calculating an estimated value of the pressure in the intake pipe when the throttle valve is closed based on the pressure value of (2); and the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. An engine control throttle valve open / closed state detecting device, comprising: throttle valve closed state detecting means for determining that the throttle valve is in a closed state. 5. An engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; a pressure detecting means for detecting an intake pipe pressure of the engine; and the throttle valve at least according to the engine speed. First and second related to the intake pipe pressure when the valve is closed
Pressure value calculating means for calculating a pressure value of the following; parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculating means for storing the obtained representative value as a learning value; atmospheric pressure detecting means for detecting atmospheric pressure; and learning value initial value calculating means for calculating an initial value of the learning value based on the atmospheric pressure. Pressure estimation value calculating means for calculating an estimated value of the intake pipe pressure when the throttle valve is in a closed state based on the learning value and the first and second pressure values; An engine control throttle valve open / closed state detecting device, comprising: throttle valve closed state detecting means for determining that the throttle valve is closed when the estimated value is smaller than a predetermined relation. 6. An engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; a pressure detecting means for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
Pressure value calculating means for calculating a second pressure value; and parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculating means for storing a representative value obtained by processing as a learning value; and a throttle valve for determining that the throttle valve is in a closed state when the parameter is smaller than the learning value in a predetermined relationship. An engine control throttle valve open / closed state detection device comprising: a closed state detection unit. 7. The pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at high altitude as the first pressure value, and calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude. The corresponding value is set to the second pressure value, and the parameter calculating means calculates a difference between a difference between the intake pipe pressure and the first pressure value with respect to a difference between the second pressure value and the first pressure value. The ratio is the parameter, the learning value calculation means stores the parameter as the learning value when the parameter is smaller than the learning value, and stores the parameter as the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. When the learning value is gradually increased and stored, the throttle valve closed state detecting means, when the parameter is smaller than a value obtained by adding a predetermined value to the learning value,
7. The engine control throttle valve open / closed state detecting device according to claim 6, wherein the throttle valve is determined to be in a closed state. 8. An engine speed calculating means for calculating an engine speed corresponding to a driving timing of the engine; a pressure detecting means for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
Pressure value calculating means for calculating a first pressure value and a second pressure value;
And a filtered pressure value calculating means for calculating a second filtered pressure value; a parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second filtered pressure values; Learning value calculating means for storing a representative value obtained by performing time-series arithmetic processing as a learning value; and a throttle valve closing state based on the learning value and the first and second pressure values. Pressure estimation value calculating means for calculating an estimated value of the intake pipe pressure at the time of, and a throttle for determining that the throttle valve is closed when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship. An engine control throttle valve open / closed state detecting device comprising: a valve closed state detecting means. 9. The pressure value calculating means sets a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude as the first pressure value, and calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at a low altitude. The corresponding value is defined as the second pressure value, and the filtered pressure value calculating means performs a first-order low-pass filtering process on the first and second pressure values to perform a first and second filtering. A pressure value; and the parameter calculating means calculates a ratio of a difference between the intake pipe pressure and the first filtered pressure value to a difference between the second filtered pressure value and the first filtered pressure value. The learning value calculating means stores the parameter as the learning value when the parameter is smaller than the learning value, and stores the learning value when the parameter is equal to or more than the learning value and smaller than a predetermined value. Gradually increase The pressure estimation value calculation means multiplies a difference between the second pressure value and the first pressure value by the learning value, and further stores the first estimated value.
The throttle valve closed state detecting means is configured to close the throttle valve when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. 9. The engine control throttle valve open / closed state detecting device according to claim 8, wherein the state is determined to be a state. 10. An engine speed calculating means for calculating an engine speed corresponding to a drive timing of the engine; a pressure detecting means for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
And a pressure value calculating means for calculating a second pressure value. The first pressure value calculating means calculates the first pressure value only when it is determined that the intake pipe pressure in the closed state of the throttle valve is in an increasing direction based on the first pressure value. A first filtered pressure value calculating means for calculating a first filtered pressure value by filtering the pressure value of the above, and an intake pipe pressure when the throttle valve is closed based on the second pressure value. A second filtered pressure value calculating means for filtering the second pressure value and calculating a second filtered pressure value only when it is determined that the first and second pressure values are in the increasing direction; Parameter calculation means for calculating a parameter representing the relationship of the intake pipe pressure to the post-filter pressure value; and learning value calculation means for storing a representative value obtained by performing a time-series calculation process on the parameter as a learning value; The study Pressure estimated value calculating means for calculating an estimated value of the pressure in the intake pipe when the throttle valve is in a closed state based on the pressure value and the first and second pressure values; An engine control throttle valve open / closed state detecting device, comprising: throttle valve closed state detecting means for judging that the throttle valve is closed when a predetermined relation is small. 11. The pressure value calculating means calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at a high altitude in the first place.
And a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as the second pressure value. The first post-filter pressure value calculating means sets the first pressure value to Only when the pressure value is larger than the first post-filter pressure value, the first pressure value is subjected to a first-order low-pass filtering process to obtain the first post-filter pressure value, and the second post-filter pressure value calculation The means performs primary low-pass filtering on the second pressure value only when the second pressure value is greater than the second filtered pressure value, and performs the second filtered pressure value on the second pressure value. The parameter calculation means calculates a ratio of a difference between the intake pipe pressure and the first filtered pressure value to a difference between the second filtered pressure value and the first filtered pressure value, using the parameter as a parameter. The learning value calculation means is configured to When the parameter is smaller than the learning value, the parameter is stored as the learning value, and when the parameter is equal to or larger than the learning value and smaller than a predetermined value, the learning value is gradually increased and stored, and the pressure estimation value calculation is performed. Means for multiplying a difference between the second pressure value and the first pressure value by the learning value;
The throttle valve closed state detecting means is configured to close the throttle valve when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. 11. The engine control throttle valve open / closed state detecting device according to claim 10, wherein the state is determined to be a state. 12. An engine speed calculating means for calculating an engine speed corresponding to a driving timing of the engine; a pressure detecting device for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
Pressure value calculating means for calculating a second pressure value; and parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Learning value calculation means for storing a representative value obtained by the processing as a learning value; and a pressure in the intake pipe when the throttle valve is closed based on the learning value and the first and second pressure values. Pressure estimation value calculating means for calculating an estimated value, and performing a filtering process on the pressure estimated value only when it is determined that the pressure estimated value is in a decreasing direction based on the pressure estimated value, and performing a filtered pressure estimation. A filtered pressure estimated value calculating means for calculating a value, and a switch for determining that the throttle valve is closed when the intake pipe pressure is smaller than the filtered pressure estimated value in a predetermined relationship. Engine control throttle valve opening and closing state detecting device and a liter valve closed state detecting means. 13. An engine speed calculating means for calculating an engine speed corresponding to an engine drive timing; a pressure detecting means for detecting an intake pipe pressure of the engine; First related to the intake pipe pressure when the throttle valve is closed
Pressure value calculation means for calculating a second pressure value; parameter calculation means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Rotation speed change detection means for detecting that the rotation speed is equal to or more than a value, timer means for operating for a predetermined period after the rotation speed change detection means detects a change in the engine speed, and when the timer means is not operating. Learning value calculating means for storing, as the learning value, a representative value obtained by calculating the parameters in a time-series manner, wherein the throttle valve is provided based on the learning value and the first and second pressure values. Pressure estimated value calculating means for calculating an estimated value of the pressure in the intake pipe in the closed state; and when the intake pipe pressure is smaller than the estimated pressure value in a predetermined relationship, the throttle valve is closed. Throttle valve opening and closing state detecting device for an engine control and a throttle valve closed state detecting means for determining that the state. 14. The pressure value calculating means calculates a value corresponding to the intake pipe pressure when the throttle valve is closed at high altitude in the first state.
And a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as the second pressure value. The parameter calculation means calculates the second pressure value, the first pressure value, The ratio of the difference between the intake pipe pressure and the first pressure value with respect to the difference is set as the parameter, and the learning value calculation unit stores the parameter as the learning value when the parameter is smaller than the learning value. When the parameter is greater than or equal to the learning value and smaller than a predetermined value, the learning value is gradually increased and stored, and the pressure estimation value calculating means calculates a difference between the second pressure value and the first pressure value. Multiplying the difference by the learning value;
The throttle valve closed state detecting means is configured to close the throttle valve when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. 14. The engine control throttle valve open / closed state detecting device according to claim 13, wherein the state is determined to be a state. 15. An engine speed calculating means for calculating an engine speed corresponding to an engine drive timing, a pressure detecting means for detecting an intake pipe pressure of the engine, and a bypass intake passage for bypassing a throttle valve in the intake pipe. A bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage; and at least an engine speed and a bypass air flow rate related to the intake pipe pressure when the throttle valve is closed according to the bypass air flow rate. Pressure value calculating means for calculating first and second pressure values; parameter calculating means for calculating a parameter representing a relationship of the intake pipe pressure with respect to the first and second pressure values; Air flow rate change detecting means for detecting that the air flow rate is equal to or greater than a predetermined value; and Timer means that operates for a predetermined period after detecting a change in air flow rate; and learning that stores a representative value obtained by performing a time-series arithmetic processing on the parameter as the learning value when the timer means is not operating. Value calculation means; pressure estimation value calculation means for calculating a pressure estimation value of the intake pipe when the throttle valve is in a closed state based on the learned value and the first and second pressure values; An throttle valve open / closed state detecting device for engine control, comprising: throttle valve closed state detecting means for determining that the throttle valve is closed when the pressure is small in a predetermined relationship with the pressure estimated value. 16. An engine speed calculating means for calculating an engine speed corresponding to a driving timing of an engine, a pressure detecting means for detecting an intake pipe pressure of the engine, and a bypass intake passage for bypassing a throttle valve in the intake pipe. A bypass air flow rate calculating means for estimating and calculating a bypass air flow rate of the bypass intake passage at least according to the presence or absence of an air conditioner load; and when the throttle valve is closed according to at least the engine speed and the bypass air flow rate. Pressure value calculating means for calculating first and second pressure values related to the intake pipe pressure, and parameter calculating means for calculating a parameter representing a relationship between the first and second pressure values and the intake pipe pressure. Learning to store, as the learning value, a representative value obtained by performing time-series arithmetic processing on the parameter. Value calculating means, timer means that operates for a predetermined period after the air conditioner load changes from off to on, and updating of the learning value during the operation of the timer means, wherein the parameter matches the learning value. A bypass air flow rate correcting means for correcting the bypass air flow rate so that the estimated value of the intake pipe pressure when the throttle valve is closed is based on the learned value and the first and second pressure values. Pressure estimation value calculation means for calculating; and throttle valve closed state detection means for determining that the throttle valve is in a closed state when the intake pipe pressure is smaller than the pressure estimation value in a predetermined relationship. Engine control throttle valve open / closed state detection device. 17. The pressure value calculation means calculates a value corresponding to an intake pipe pressure when the throttle valve is closed at a high altitude in the first place.
And a value corresponding to the intake pipe pressure when the throttle valve is closed at low altitude is set as the second pressure value. The parameter calculation means calculates the second pressure value, the first pressure value, The ratio of the difference between the intake pipe pressure and the first pressure value with respect to the difference is set as the parameter, and the learning value calculation unit stores the parameter as the learning value when the parameter is smaller than the learning value. When the parameter is greater than or equal to the learning value and smaller than a predetermined value, the learning value is gradually increased and stored.The bypass air flow rate correction means determines that the parameter is smaller when the parameter is smaller than the learning value. Correcting the bypass air flow rate so as to match the learned value, and gradually increasing the bypass air flow rate when the parameter is equal to or greater than the learned value and smaller than a predetermined value; The force estimation value calculation means multiplies the difference between the second pressure value and the first pressure value by the learning value, and further calculates the first pressure value.
The throttle valve closed state detecting means is configured to close the throttle valve when the intake pipe pressure is smaller than a value obtained by adding a predetermined value to the estimated pressure value. 17. The engine control throttle valve open / closed state detecting device according to claim 16, wherein the state is determined to be a state.