JP3147678B2 - Idle operation control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an idle operation control device suitable for idle control of an internal combustion engine for a vehicle.

[0002]

2. Description of the Related Art An internal combustion engine for driving a vehicle (hereinafter referred to as an engine) mounted on an automobile or the like is subjected to idle operation control so as to maintain a predetermined idle rotation speed when there is no load. As means for performing such idle rotation speed control, an idle operation output adjusting means called an idle speed controller (ISC) has become widespread. Such means adjusts the output state of the engine while electronically controlling the intake air introduction state so that a desired idle rotation speed state can be maintained at no load.

[0003] By setting the idle rotation speed low, fuel efficiency can be improved. However, when a load torque is applied, a transient decrease in rotation occurs, and engine stall (hereinafter referred to as engine stall) tends to occur. A representative example of the load torque applied during the idling operation is a load torque by a power steering device that receives a hydraulic pressure supply from an engine-driven hydraulic pump.

[0004] For this reason, even when a load torque is applied, the idle rotation speed is always set to a high value so that the rotation does not decrease enough to reach the engine stall. However, as described above, if the idling rotational speed is always set to a high value in preparation for the application of the load torque, the fuel consumption will be unnecessarily deteriorated. And cannot be achieved together.

In view of this situation, Japanese Patent Application Laid-Open No.
An engine control device disclosed in Japanese Patent No. 71406 is proposed. This device uses a high idle rotation speed when the power steering is operating, a low idle rotation speed when the power steering is not operating, and prevents the engine from stalling even when the power steering is applied during the idle operation. The goal is to achieve improved fuel economy.

[0006]

However, the above-mentioned prior art is a control only when the vehicle is stopped, and when the vehicle is in a no-load state (or a state close to a no-load state) during traveling, the idle speed is particularly high. The controller is not controlled. There are idle speed controllers that can be adjusted even during traveling, and it is possible to improve fuel efficiency by controlling the idle speed controller during traveling.However, there is a risk that engine stoppage may occur due to artificial acceleration / deceleration operations by the driver. There is a problem how to control the idle speed controller.

The present invention has been made in view of the above problems, and provides an idling operation control device capable of realizing improvement in engine fuel efficiency while reliably avoiding engine stall due to artificial acceleration / deceleration operations. The purpose is to do.

[0008]

According to the present invention, there is provided an idling operation control apparatus according to the present invention, which is capable of adjusting the output of an internal combustion engine for driving a vehicle so that the output of the internal combustion engine can be adjusted for idling. Adjusting means; a first control mode for controlling the idling operation output adjusting means such that the rotation speed of the internal combustion engine becomes the first target rotation speed during the idling operation; and Mode selection means for selecting a second control mode for controlling the output adjustment means for idling operation so that the rotation speed becomes a second target rotation speed lower than the first target rotation speed; Control means for controlling the output adjustment means for idling operation in the control mode selected by the selection means, in an idle operation control device provided with a vehicle speed detection means for detecting the speed of the vehicle, An artificial operation detecting means for detecting a state of an artificial operation relating to a change in the speed of the vehicle, wherein the mode selecting means receives detection information from the vehicle speed detecting means and the artificial operation detecting means, and Is higher than the reference speed, the second control mode is selected, and during the selection of the second control mode, the mode is switched to the first control mode when the condition for switching to the first control mode is satisfied. And the condition for switching to the first control mode is set such that the vehicle speed is equal to or lower than the reference speed and an artificial operation relating to a change in the vehicle speed is performed.

According to a second aspect of the present invention, there is provided the idle operation control device according to the first aspect, wherein the artificial operation detection means includes a negative acceleration in which the acceleration of the vehicle is set in advance.
When the vehicle speed is lower than the reference acceleration , the vehicle has a sudden braking determination unit that determines that an artificial sudden braking operation has been given to the vehicle, and when the sudden braking determination unit determines that the artificial sudden braking operation is being performed. It is characterized in that detection information indicating that the artificial operation has been performed is output.

According to a third aspect of the present invention, there is provided the idle operation control device according to the first or second aspect, wherein the artificial operation detecting means detects an artificial operation based on an artificial operation state related to a vehicle speed of the vehicle. Vehicle speed change determination means for determining whether or not a manual vehicle speed change operation has been performed, and when the vehicle speed change determination means determines that the artificial vehicle speed change operation has been performed, the artificial operation has been performed. It is characterized by outputting detection information to the effect.

[0011] In the configuration of 請 Motomeko 1 or 2, having an idle determination means for outputting an idle command information or off idle command information to the control unit based on the manual operation state regarding the vehicle speed of the vehicle, When the artificial operation detecting means receives the information from the idle determining means and switches from the idle command state to the off-idle command state, it outputs detection information indicating that the artificial operation has been performed.
(Aspect 1) .

Further,請 Motomeko 1-3, in the structure according to any of embodiments 1, wherein the mode selection means, after selecting the control mode of the first, vehicle speed under conditions of less than the reference speed , until the operation state of the internal combustion engine is idle stable state is configured to continue the selection of the control mode of the first
(Aspect 2) . Further,請 Motomeko 3, in the structure according to any of embodiments 1 and 2, the mode selection means, after selecting the control mode of the first, under the conditions of the vehicle speed is more than the reference speed, vehicle speed configured such that the vehicle receives the detection information from the detecting means until idling rotation range over speed condition of the internal combustion engine to continue selecting the control mode of the first
(Aspect 3) .

Further,請 Motomeko 3, in the structure according to any of embodiments 1 and 2, the mode selection means, after selecting the control mode of the first, vehicle speed under conditions of less than the reference speed The first control mode until the operation state of the internal combustion engine becomes an idling stable state or the vehicle enters a speed state equal to or higher than an idle rotation range of the internal combustion engine in response to detection information from the vehicle speed detection means. Configured to continue selecting
(Aspect 4) .

[0014]請 Motomeko 1-3, in the structure according to any of embodiments 1 to 4, the reference speed is set as the lower limit of the speed range that does not use the maximum load range of the power steering device (Aspect 5) . Further,請 Motomeko 1-3, in the structure according to any of embodiments 1 to 5,
The idling output adjusting means comprises a bypass passage provided in parallel with the intake passage of the internal combustion engine, also it is composed of a bypass opening adjusting means interposed in said bypass passage
Good (aspect 6) .

Further,請 Motomeko 1-3, in the structure according to any of embodiments 1 to 6, in the vehicle, the automatic transmission is provided which is connected via the internal combustion engine and fluid coupling, the automatic When the transmission is set in the travel range, the transmission may be set to perform idle operation control in the first control mode or the second control mode (aspect 7) .

[0016]

In the idle operation control device according to the first aspect of the present invention, the mode selection means controls the idle operation output adjustment means so that the rotation speed of the internal combustion engine becomes the first target rotation speed during the idle operation. A first control mode for controlling the engine, and a rotation speed of the internal combustion engine during the idling operation is controlled by the first control mode.
A second control mode for controlling the idle operation output adjusting means so that the second target rotation speed is lower than the second target rotation speed. The idle operation output adjusting means is controlled in the control mode selected by the means.

At this time, the mode selection means receives the detection information from the power steering operation detection means and the vehicle speed detection means, and selects the second control mode when the vehicle speed is higher than the reference speed, and selects the second control mode. While the control mode is selected, if the condition for switching to the first control mode, that is, the condition that the vehicle speed is equal to or lower than the reference speed and an artificial operation relating to the change of the vehicle speed is performed, is satisfied, the first control mode is set. Select the control mode selection.

If the vehicle speed is lower than the reference speed and an artificial operation for changing the vehicle speed is performed, engine stall is likely to occur, but the first control mode for keeping the engine at a relatively high speed is selected. Engine stall during idle control is avoided. On the other hand, if the vehicle speed is higher than the reference speed, engine stall does not occur even if an artificial operation related to the change of the vehicle speed is performed.
Since the output of the idle operation output adjusting means is suppressed to a low level, the vehicle can travel while suppressing fuel consumption without causing engine stall.

In the idle operation control device according to the second aspect of the present invention, in the artificial operation detecting means, the sudden braking determining means determines that the acceleration of the vehicle is greater than a predetermined negative reference acceleration. If the vehicle speed is too low, it is determined that an artificial sudden braking operation has been performed on the vehicle, and in this case, detection information indicating that the artificial operation has been performed is output. Therefore, the first control mode for keeping the engine at a relatively high speed is selected at the time of sudden braking that easily causes the engine stall, and the engine stall during the idle control is avoided.

In the idle operation control device according to the third aspect of the present invention, the vehicle speed change judging means of the artificial operation detecting means includes an artificial vehicle speed changing operation based on an artificial operation state relating to the vehicle speed of the vehicle. Is determined, and if it is determined that an artificial vehicle speed changing operation has been performed, detection information indicating that the artificial operation has been performed is output.
As a result, the first control mode for keeping the engine at a relatively high speed is selected during a vehicle speed change operation in which engine stall is likely to occur, and engine stall during idle control is avoided.

In the case of the first embodiment, when the manual operation detecting means switches from the idle command state to the off-idle command state in response to the information from the idle determining means, the manual operation is not performed. Since the detection information indicating that the operation has been performed is output, when switching from the idle command state in which engine stall is likely to occur to the off-idle command state,
The first control mode for keeping the engine at a relatively high speed is selected, and engine stall during idle control is avoided.

In the case of the second aspect, the mode selecting means may select the first control mode and, if the vehicle speed is equal to or lower than the reference speed, the operating state of the internal combustion engine may be set to an idle state. Since the selection of the first control mode is continued until the engine becomes stable, the first control mode for keeping the engine at a relatively high speed is selected as long as there is a possibility that the engine will stall. Stalls are reliably avoided.

In the case of the above configuration, the mode selection means may select the first control mode and, under the condition that the vehicle speed is equal to or less than the reference speed, the detection information from the vehicle speed detection means. As a result, the selection of the first control mode is continued until the speed of the vehicle becomes equal to or higher than the idling speed range of the internal combustion engine. Therefore, as long as engine stall may occur, the engine is driven at a relatively high speed. The first control mode to be kept is selected, and engine stall during idle control is reliably avoided.

[0024] In the case of the above-described aspect 4, the mode selection means may select the first control mode and, when the vehicle speed is equal to or lower than the reference speed, the operating state of the internal combustion engine may be idle. Since the selection of the first control mode is continued until the vehicle enters a stable state or receives a detection information from the vehicle speed detecting means and the vehicle enters a speed state equal to or higher than an idle rotation range of the internal combustion engine, the engine stall is stopped. The first control mode for keeping the engine at a relatively high speed is selected as long as there is a possibility that the engine will stall, and engine stall during idle control is reliably avoided.

In the case of the configuration as in the above-described mode 5, since the reference speed is set as a lower limit value of a speed range in which the maximum load range of the power steering device is not used, when the vehicle speed is higher than the reference speed. Thus, there is no possibility that the power steering load will suddenly increase, and even if the low output second control mode is selected, engine stall will not occur.

In the case of the sixth aspect, the idle operation output adjusting means adjusts the opening of the bypass passage provided in parallel with the intake passage of the internal combustion engine by the bypass opening adjusting means. Thus, the output for idling operation is adjusted. Therefore, the output for idling operation can be adjusted separately from the main control of the engine by controlling the opening degree of the intake passage.

When the automatic transmission is set in the travel range , the automatic transmission is set to perform the idle operation control in the first control mode or the second control mode. Therefore, during traveling, it is possible to reliably perform idle control that can improve fuel efficiency while avoiding engine stall.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an idle operation control device as one embodiment of the present invention. This idle operation control device is provided for idling an automobile engine (an internal combustion engine for driving a vehicle) (not shown), and as shown in FIG. 1, an idle speed controller (ISC) 10 as an idle operation output adjusting means. And an electronic control unit (ECU) 20 for controlling the idle speed controller 10.

The ISC 10 is provided with a throttle valve 4 of the intake pipe 2.
, A needle-like bypass valve 6 capable of adjusting the opening of the bypass pipe 5, and a first idle 9, and the bypass valve 6 is closed by a compression coil spring 7. When the bypass valve 6 is duty-driven by a solenoid 8, the opening of the bypass pipe 5 is adjusted. In FIG. 1, reference numeral 50 denotes a throttle opening sensor.

The ECU 20 electronically controls not only the ISC 10 but also other parts of the engine. When attention is paid to the control in the running mode of the ISC 10, the ECU 20 includes the ISC 1
A mode selection means 22 for selecting a control mode of 0, an idle control means 24 for controlling the ISC 10 in the control mode selected by the mode selection means 22, and an engine speed feedback condition determination means 26 are provided.

Whether the vehicle is in the traveling mode or the stop mode is determined from the range selection information of the automatic transmission, and if the automatic transmission is in the traveling range (D range, 1st and 2nd speed range, etc.). When the automatic transmission is in the stop range (N range or the like), the ISC 10 is controlled by the control dedicated to the N range. Here, the description of the control of the N range is omitted.

The mode selection means 22 controls a first control mode (hereinafter referred to as a normal control mode) for controlling the ISC 10 so that the rotation speed of the engine becomes the first target rotation speed during the idling operation. The second control mode (hereinafter referred to as a low-speed control mode) for controlling the ISC 10 so that the rotation speed of the ISC 10 becomes a second target rotation speed lower than the first target rotation speed is selected.

In the normal control mode, the ISC 10 is set to a relatively large output state and a relatively high idling speed is set so that a stable idle operation state can be maintained even when a large load is applied to the engine. This is a load control mode for the purpose of reliably avoiding engine stall (hereinafter referred to as engine stall) and obtaining stable idling operation.

In the low speed control mode, the ISC 10 is set to a relatively small output state while maintaining a relatively low idle speed so that a stable idle operation state can be maintained unless a large load is applied to the engine. This is a no-load control mode for the purpose of suppressing fuel consumption. The mode selection means 22 includes an automatic transmission 30, a power steering switch 32, a vehicle speed sensor 34, a key switch (IG switch) 36, a throttle opening sensor 50, an accelerator opening sensor 38, an engine speed sensor 46, and an artificial operation detection. The mode is selected based on each information from the means 40.

The power steering device mounted on the vehicle is a hydraulic power steering device that assists steering by using the hydraulic pressure of an engine-driven oil pump. The power steering switch 32 is provided with a hydraulic pressure for steering assist ( When the power steering oil pressure reaches the reference value, the power is turned on (during the power steering operation), and when the steering assist oil pressure (power steering oil pressure) does not reach the reference value, the power is turned off (the power steering is not operated).

The artificial operation detecting means 40 will be described later. Idle control should be performed in the low-speed control mode if possible, so as to reduce fuel consumption.
Don't invite stalling. Therefore, in the present idle operation control device, if there is a possibility of causing engine stall, a normal control mode that is not suitable for suppressing fuel consumption but can reliably avoid engine stall is selected. A low-speed control mode capable of suppressing fuel consumption is selected.

The case where an engine stall may be caused is a case where a large load is applied to the engine and a sudden decrease in the rotation of the engine occurs transiently. Specifically, the following cases are considered. . In some cases, the power steering is activated and a large power steering load is applied to the engine. In particular, since the power steering load suddenly increases at the time of stationary operation, unexpected stationary operation is likely to cause engine stall. However, when the vehicle speed increases to a certain degree, turning G exceeds the steering stability limit if a large steering angle or a sharp steering operation is performed to obtain a large power steering assist equivalent to stationary steering. No load is applied. Therefore, it is possible to limit the occurrence of engine stall by the power steering load to a predetermined speed or less.

In some cases, an operation such as abruptly changing the traveling speed is performed in a low vehicle speed state. In this case, for example, the tire may be locked by sudden braking, and if the tire is locked, the engine is likely to stall.
Further, even when the tires are in a semi-locked state, the engine stalls easily in the case of low idling. Further, a driving operation such as so-called "twiddle operation" in which the vehicle is accelerated from a stop and then suddenly stopped again corresponds to this. At this time, the vehicle returns from an idle state to an idle state with an engine load via an off-idle state. As a result, a change in the load of the engine in the vicinity of the idling operation is remarkably likely to cause engine stall.

In the present apparatus, when there is a possibility that such an engine stall will occur, the engine stall is reliably avoided in the normal mode. First, the cause of engine stall due to the application of a large power steering load is that the vehicle
(A is, for example, a speed of about 30 to 40 km / h) or less, and when the power steering is operated, the normal mode is set.

If the power steering hydraulic pressure does not reach the reference value, the power steering switch 32 for detecting the presence / absence of the operation of the power steering is turned off and determines that the power steering is not operating. Therefore, even if the steered wheels have a large steering angle, if they are stopped, it is determined that the power steering is off. However, if the steered wheels have a large steering angle in this way, the steered wheels are often suddenly steered by stationary steering.

Therefore, when the vehicle is activated in the normal mode by operating the power steering at a predetermined value A or less, a condition for canceling the normal mode (here, a condition that the vehicle exceeds the predetermined value A) is satisfied. Until the normal mode is maintained. Also, when starting the engine, the control is started without the power steering operation information being entered from the beginning.However, the engine may be stopped with the steered wheels remaining at a large steering angle, for example, in the maximum steering angle state. Immediately after the start, the steered wheels are frequently steered by stationary steering. Therefore, the normal mode is set immediately after the engine is started, and the normal mode is maintained until the vehicle exceeds the predetermined value A, so that the engine stall due to the application of a large power steering load can be reliably avoided.

When an operation such as abruptly changing the running speed is performed artificially in a low vehicle speed state, the mode is set through the artificial operation detecting means 40 as follows. The artificial operation detecting means 40 detects when an artificial operation relating to the traveling speed of the vehicle is performed, and determines whether or not a sudden braking operation is performed, and the artificial operation is performed. And a vehicle speed change determination unit 44 that determines whether an artificial vehicle speed change operation has been performed and outputs information indicating that an artificial operation has been performed. Have.

The sudden braking determination means 42 determines whether or not a sudden braking operation has been performed, while detecting the vehicle acceleration. When the vehicle acceleration falls below a negative set value B, the sudden braking operation is performed. Is determined. The set value B in this case is a deceleration of, for example, about 4 to 6 km / h / s, and is a deceleration that does not occur in normal deceleration. Further, the artificial vehicle speed change operation performed by the vehicle speed change determination means 44 means a case where the engine changes from an idle state to an off-idle state, and as described above, the engine is switched from an idle state to an off-idle state and the engine load is changed. As a countermeasure against engine stall caused by an operation of returning to the idle state, information indicating that an artificial vehicle speed change operation has been performed when the engine has changed from the idle state to the off-idle state without waiting for all of the operations.

When an artificial operation relating to the running speed of the vehicle is performed, the normal mode is set. Thereafter, the normal mode is maintained until a condition that can cancel the normal mode is satisfied, and a large power steering load is applied. To avoid stalling. As a result, an engine stall at the time of sudden braking in a low vehicle speed state and at the time of a driving operation in which the vehicle is accelerated from a stop called so-called "twiddled operation" and suddenly stopped again is reliably avoided. It is.

When the normal mode is set due to an artificial operation relating to the traveling speed of the vehicle, the conditions for releasing the normal mode include the condition that the vehicle exceeds a predetermined value A and the engine rotation. Numerical feedback condition (N
e-F / B). This condition is determined by the engine speed feedback condition determining means 26.
The key switch 36 and the accelerator opening sensor 3
8, when the idle state has elapsed for a predetermined time or the state without load change has elapsed for a predetermined time based on information from the throttle opening sensor 50, the vehicle speed sensor 34, the timer 48, an idle switch (not shown), or the like. That is, when the engine is idling at a stable speed, the engine speed feedback condition is satisfied.

Further, the conditions for canceling the normal mode in the setting of the normal mode when the state changes from the idle state to the off-idle state further include that the turbine speed in the D range of the automatic transmission is higher than the engine idle speed. Since the vehicle speed increases and such a condition is satisfied when the vehicle speed is equal to or higher than the predetermined value C, the condition that the vehicle speed is equal to or higher than the predetermined value C is the release condition of the normal mode.

The predetermined value C in this case is, for example, 4 to 6 km / h.
The value is as low as d. Since the idle operation control device as one embodiment of the present invention is configured as described above, the idle operation control becomes angry, for example, as shown in the flowchart of FIG. First, the control is started when the key switch 36 is turned on, and the normal mode is initialized in advance. Then, first, it is determined whether or not the automatic transmission is in the D range (step S10). If not, the process proceeds to step S44 to set the control for the N range.

If the automatic transmission is in the D range, the process proceeds to step S12, where it is determined whether the vehicle speed is higher than a predetermined value A. If the vehicle speed is equal to or lower than the predetermined value A, the process proceeds to step S14, and it is determined whether the power steering is on. If the power steering is not on, the process proceeds to step S16, where it is determined whether or not the engine is off-idle from the throttle opening or the accelerator opening. Starting acceleration from idle will result in off-idle,
Proceeding to step S18, the flag 1 is set and acceleration is not started.
Are not set, the process proceeds to step S20.

In step S20, the change in vehicle speed is set to a set value B.
Then, it is determined whether or not there has been a sudden deceleration. If there is rapid deceleration, the process proceeds to step S22, and flag 2 is set. If there is no rapid deceleration, flag 2 is not set.
Proceed to step S24. In step S24, it is determined whether or not the vehicle speed has exceeded the set value C, that is, whether or not there is no fear of sudden deceleration after the vehicle has started. If the vehicle speed exceeds the set value C, the flag 1 is cleared in step S26. If the vehicle speed does not exceed the set value C, the process proceeds to step S28 without changing the set state of the flag 1.

In step S28, it is determined whether the engine speed feedback condition (Ne-F / B) is satisfied. If Ne-F / B is established, both flag 1 and flag 2 are cleared in step S30. If Ne-F / B is not established, the set states of flag 1 and flag 2 are not changed. Proceed to step S32.

In this step S32, it is determined whether or not the flag 1 has been cleared. If the flag 1 has been cleared, the process proceeds to step S34. If the flag 1 has not been cleared, the process proceeds to step S38 to set the normal mode. Step S3
When proceeding to 4, it is determined whether or not the flag 2 has been cleared.
When the flag 2 is cleared, the process proceeds to step S36,
If has not been cleared, the process proceeds to step S38 to set the normal mode.

When proceeding to step S36, it is determined whether or not the previous time is the low-speed mode. If the previous time is not the low-speed mode, the process proceeds to step S38. The normal mode is maintained. If the previous time is the low-speed mode, the process proceeds to step S42. , Keep the low speed mode. On the other hand, if it is determined in step S12 that the vehicle speed is higher than the predetermined value A, the process proceeds to step S40, where both the flag 1 and the flag 2 are cleared, and the process proceeds to step S42.
Set to low-speed mode.

The control operation is performed as described above. The control operation will be described with reference to a specific example shown in FIG. 3. In the example shown in FIG. 3, after the automatic transmission starts the engine in the N range, the automatic transmission Is the D range (time T1). Here, this control is started, and after starting, the normal mode is set until the vehicle speed reaches the predetermined speed A, and the ISC 10 is set to a relatively high output state corresponding to a high idle speed.
Thereafter, when the vehicle speed reaches the predetermined speed A (time T2), the low speed mode is set, and the ISC 10 is set to a relatively low output state corresponding to the low idle speed.

Thereafter, even if the vehicle speed is reduced, the power steering pressure is not generated unless the steering wheel is operated, so that the low speed mode is maintained. Fuel economy driving is performed. In this case, since the steering wheel operation is performed at time T3 after the vehicle stops, after the steering wheel operation, a power steering pressure is generated, the power steering switch is turned on, and the mode is switched to the normal mode. For this reason, the ISC 10 is set again to a high output state that increases the idle speed. Thus, even when a large power steering addition such as a stationary operation is applied, the engine rotation speed Ne does not decrease so much and engine stall does not occur. During power steering operation,
As conventionally performed, the output of the ISC 10 is controlled to increase by the power-up amount.

Thereafter, when the steering operation is completed, the power steering switch is turned off, but the normal mode is continued until the vehicle speed reaches the predetermined speed A. Then, when the vehicle speed again reaches the predetermined speed A (time T4), the low speed mode is set again, the ISC 10 is set to a relatively low output state corresponding to a low idle speed, and fuel-efficient traveling is performed.

Thereafter, when the sudden braking operation is performed at time T5 and the change in vehicle speed falls below the predetermined deceleration B, the mode is switched to the normal mode. For this reason, the ISC 10 is set again to a high output state that increases the idle speed,
Even if the wheels are locked, the engine rotation speed Ne does not decrease so much and engine stall does not occur. Thereafter, when the engine rotation speed Ne becomes stable, Ne-F at time T6.
Since / B is established, there is no danger of engine stall, the low speed mode is set again, the ISC 10 is set to a relatively low output state corresponding to the low idle speed, and fuel-efficient traveling is performed.

Then, the low-speed mode is maintained. However, when acceleration is started at time T7 after returning to the idling operation state again, the mode is switched to the normal mode because it becomes off-idle. When Ne-F / B is established at time T8,
There is no danger of engine stall, and the low-speed mode is set again. Further, when acceleration is started at time T9 after returning to the idling operation state again, the vehicle is switched to the normal mode because the vehicle becomes off-idle, and the vehicle speed reaches the predetermined vehicle speed C at time T10. Is done.

As described above, in the present idle operation control device, if there is a possibility that an engine stall will occur through the control of the ISC 10, the normal mode is definitely set to avoid the engine stall and there is a possibility that the engine stall will occur. As soon as it disappears, the mode is switched to the low-speed mode and the fuel-efficient traveling is performed.

[0059]

As described above in detail, according to the idling operation control apparatus of the present invention, the idling operation of the internal combustion engine for driving the vehicle can be adjusted for idling the internal combustion engine. Output control means, a first control mode for controlling the output control means for idling operation so that the rotation speed of the internal combustion engine attains a first target rotation speed during the idling operation, and the internal combustion engine during the idling operation. Mode selecting means for selecting a second control mode for controlling the idling operation output adjusting means such that the rotation speed of the motor becomes a second target rotation speed lower than the first target rotation speed; Control means for controlling the output adjustment means for idling operation in the control mode selected by the mode selection means, in an idling operation control device provided with a vehicle speed detection means for detecting the speed of the vehicle, An artificial operation detecting means for detecting a state of an artificial operation relating to a change in the speed of the vehicle, wherein the mode selecting means receives detection information from the vehicle speed detecting means and the artificial operation detecting means, and Is higher than the reference speed, the second control mode is selected, and during the selection of the second control mode, the mode is switched to the first control mode when the condition for switching to the first control mode is satisfied. And the switching condition to the first control mode is set such that the vehicle speed is equal to or lower than the reference speed and an artificial operation related to the change of the vehicle speed is performed. Fuel economy can be improved by low-speed idle control while avoiding engine stall during idle control.

According to a second aspect of the present invention, in the configuration of the first aspect, the artificial operation detecting means includes a negative reference acceleration in which the acceleration of the vehicle is set in advance. If it is lower than, the vehicle has a sudden braking determination unit that determines that an artificial sudden braking operation has been given to the vehicle,
When the sudden braking determination means determines that the artificial sudden braking operation is being performed, it outputs detection information indicating that the artificial braking operation has been performed. Fuel economy can be improved by low-speed idle control while avoiding engine stall.

According to a third aspect of the present invention, in the configuration of the first or second aspect, the artificial operation detecting means is configured to detect the artificial operation state based on an artificial operation state related to the vehicle speed of the vehicle. Vehicle speed change determining means for determining whether an artificial vehicle speed changing operation has been performed. If the vehicle speed change determining means determines that the artificial vehicle speed changing operation has been performed, the artificial operation is performed. With the configuration of outputting the detection information indicating that the vehicle speed has been changed, it is possible to improve the fuel efficiency by low-speed idle control while avoiding engine stall during idle control in response to an artificial vehicle speed change operation.

According to a first aspect of the present invention, in the configuration according to the first or second aspect, idle determination is performed to output idle command information or off-idle command information to the control means based on an artificial operation state relating to the vehicle speed of the vehicle. Means for detecting the manual operation when the artificial operation detecting means switches from the idle command state to the off-idle command state in response to the information from the idle determination means. With this configuration, it is possible to improve fuel economy by low-speed idle control while reliably avoiding engine stall during idle control that is likely to occur due to an off-idle command.

As described in the second aspect, claims 1 to 3
In the configuration according to any one of the first to third aspects, after the first control mode is selected, the operation state of the internal combustion engine is set to an idle stable state under a condition where the vehicle speed is equal to or lower than the reference speed. If the configuration is such that the selection of the first control mode is continued until the start , the engine stall can be more reliably avoided while improving the fuel efficiency.

Further , as in the third aspect, the third aspect is provided.
In the configuration described in any one of ( 1) and (2) , after selecting the first control mode, the mode selection means receives detection information from the vehicle speed detection means under a condition where the vehicle speed is equal to or lower than the reference speed. If the configuration is such that the selection of the first control mode is continued until the speed of the vehicle becomes equal to or higher than the idle rotation range of the internal combustion engine, the engine stall is more reliably avoided while improving the fuel efficiency. can do.

Further , as in the fourth aspect, the third aspect is provided.
In the configuration described in any one of ( 1) and (2) , after the mode control means selects the first control mode, the operating state of the internal combustion engine is set to an idle stable state under a condition where the vehicle speed is equal to or lower than the reference speed. become to or receives the detection information from the vehicle speed detecting means when the vehicle is configured as described above until the idling rotation range over speed condition of the internal combustion engine to continue selecting the control mode of the first fuel consumption While promoting the improvement of
Engine stall can be avoided more reliably.

Further , as in the fifth embodiment, claims 1 to 3
In the configuration according to any one of like 1-4, the reference speed is configured to be set as the lower limit of the speed range that does not use the maximum load range of the power steering device
Thus, the fuel consumption can be suppressed while reliably preventing engine stall. Also, as in an aspect 6, claim 1
In the configuration according to any one of the first to third aspects , the output adjustment means for idling operation includes a bypass passage provided in parallel with an intake passage of the internal combustion engine, and a bypass provided in the bypass passage. When configured with the opening adjustment means ,
While using the output adjustment means for general idle operation,
Only by changing the configuration relating to the control of the output adjustment means for idling operation, it is possible to easily realize suppression of fuel consumption while reliably preventing engine stall.

Further, according to the seventh aspect ,
In the configuration according to any one of modes 1 to 6 ,
An automatic transmission connected to the internal combustion engine via a fluid coupling is provided, and when the automatic transmission is set to a travel range, idle operation control according to the first control mode or the second control mode When set to perform, while reliably performs idle control during running, there is an advantage that it is possible to Nau line which can improve fuel efficiency while avoiding engine stalling.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a main part of an idle operation control device as one embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the idle operation control device as one embodiment of the present invention.

FIG. 3 is a time chart showing a specific control example by the idle operation control device as one embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 2 intake pipe 4 throttle valve 5 bypass pipe 6 bypass valve 7 compression coil spring 8 solenoid 9 fast idle 10 idle speed controller (ISC) as output adjustment means 20 electronic control unit (ECU) 22 mode selection means 24 idle control means 26 engine rotation Number feedback condition determining means 30 Automatic transmission 32 Power steering switch 34 Vehicle speed sensor 36 Key switch (IG switch) 38 Accelerator opening sensor 40 Artificial operation detecting means 42 Rapid braking determining means 44 Vehicle speed change determining means 46 Engine speed sensor 50 Throttle opening sensor

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-55-160132 (JP, A) JP-A-58-185976 (JP, A) JP-A-5-71406 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F02D 41/00-45/00 395 F02D 29/00-29/06

Claims (3)

(57) [Claims] An idling operation output adjusting means for adjusting an output of the internal combustion engine for idling the internal combustion engine for driving a vehicle; and a rotational speed of the internal combustion engine at the first target rotational speed during the idle operation. A first control mode for controlling the idle operation output adjusting means so that the second target rotation speed of the internal combustion engine is lower than the first target rotation speed during the idle operation. Mode selection means for selecting a second control mode for controlling the output adjustment means for idling operation, and control means for controlling the output adjustment means for idle operation in the control mode selected by the mode selection means. A vehicle speed detecting means for detecting a speed of the vehicle, and a manual operation detecting means for detecting a state of a manual operation relating to a change in the speed of the vehicle. The mode selecting means receives the detection information from the vehicle speed detecting means and the artificial operation detecting means, and selects the second control mode when the vehicle speed is higher than the reference speed, and Second
Is set to switch to the first control mode when the condition for switching to the first control mode is satisfied, and the condition for switching to the first control mode is determined when the vehicle speed is equal to the reference speed. An idling operation control device, wherein the idling operation control device is set at a speed equal to or lower than a speed and an artificial operation related to the change of the vehicle speed is performed. 2. The vehicle according to claim 2, wherein the artificial operation detecting means is configured to accelerate the vehicle.
When the degree is lower than a preset negative reference acceleration , the vehicle has a sudden braking determining means for determining that an artificial sudden braking operation has been given to the vehicle, and the sudden braking determining means includes the artificial sudden braking operation. 2. The idle operation control device according to claim 1, wherein when it is determined that the operation is performed, detection information indicating that the artificial operation has been performed is output. 3. The vehicle control device according to claim 2, wherein the artificial operation detecting unit includes a vehicle speed change determining unit configured to determine whether an artificial vehicle speed change operation is performed based on an artificial operation state related to the vehicle speed of the vehicle. 3. The method according to claim 1, wherein when the change determination means determines that the artificial vehicle speed change operation is being performed, detection information indicating that the artificial operation has been performed is output.
An idle operation control device according to any one of the preceding claims .