JP2004028288A - Safety control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safety control device retaining the operation of a device securing a power from an internal combustion engine without stopping the internal combustion engine and accelerating and decelerating the vehicle in compliance with the intention of a driver, when a device controlling the output of the internal combustion engine breaks down. <P>SOLUTION: This internal combustion engine control device is provided with the internal combustion engine, the output control device for the internal combustion engine, a device transmitting the output of the internal combustion engine to the wheels, a device intermitting the transmission of the output of the internal combustion engine to the wheels, and a failure detecting device of the output control device for the internal combustion engine. When the failure of the output control device for the internal combustion engine is detected, the transmission of the output of the internal combustion engine to the wheels is intermitted. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a safety control device for ensuring safety of a vehicle, and more particularly to a safety control device when a failure is detected in a means for controlling power output.
[0002]
[Prior art]
Generally, the power output control means of a vehicle is designed to be in a safe state even if a failure occurs. In the conventional invention, as disclosed in Japanese Patent Application Laid-Open No. 5-139190, when a failure of the output control system of the internal combustion engine is determined, the gear position is set to a predetermined value other than neutral, the clutch state is turned on, and then the internal combustion engine is turned on. There is a control device that prevents the vehicle from running out of control by stopping the power, and also prevents power steering or power brake that secures power from the internal combustion engine by supplying power from the vehicle to the internal combustion engine.
[0003]
[Problems to be solved by the invention]
However, in such a conventional control device for an internal combustion engine, when the vehicle stops, the rotation of the internal combustion engine stops, and thereafter, the device for securing power from the internal combustion engine cannot operate. Further, it is difficult for the driver to adjust the deceleration at the time of stopping the vehicle, and re-acceleration is also impossible, so that the driver's intention to avoid danger may not be reflected. The present invention has been made in view of such a conventional problem, and does not stop the internal combustion engine even when the device for controlling the output of the internal combustion engine breaks down, and operates the device for securing power from the internal combustion engine. An object of the present invention is to provide a safety control device that can maintain and reflect a driver's intention to avoid danger.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, an internal combustion engine control device according to the present invention includes an internal combustion engine, an output control device for the internal combustion engine, a device for transmitting the output of the internal combustion engine to wheels, and a wheel for output of the internal combustion engine. A device that interrupts transmission to the engine, a device that controls the rotation speed of the internal combustion engine by supplying and stopping fuel, a failure detection device of the output control device of the internal combustion engine, and a device that detects a required output of a driver. When the failure detection device of the output control device of the internal combustion engine detects a failure of the output control device of the internal combustion engine, the device for interrupting the transmission of the output of the internal combustion engine to the wheels is provided by the device. The transmission of the output to the wheels is cut off, and the device for controlling the rotation speed of the internal combustion engine by supplying and stopping the fuel is controlled so that the rotation speed of the internal combustion engine falls within a predetermined range. Further, the output required by the driver is detected, and the output required by the driver is compared with the output of the internal combustion engine to control the intermittent output transmission.
[0005]
Accordingly, the present invention can maintain the operation of the device that secures power from the internal combustion engine without stopping the internal combustion engine when the output control device of the internal combustion engine fails, and can reflect the driver's intention to avoid danger. Realize safety control.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
(Example 1)
Embodiments according to the present invention will be described below with reference to the drawings.
[0007]
First, an embodiment of a power unit according to the present invention will be described with reference to FIGS.
[0008]
FIG. 1 shows the overall configuration of a control system for a direct injection internal combustion engine 107 according to the present embodiment. The intake air introduced into the cylinder 107b is taken in from the inlet 102a of the air cleaner 102, passes through an air flow sensor (air flow meter) 103, which is one of operating state measuring means of the internal combustion engine, and controls the intake flow rate. The collector passes through the throttle body 105 in which the throttle valve 105a is housed.
Enter 106. From the airflow sensor 103, a signal indicating the intake flow rate is output to a control unit 115 which is an internal combustion engine control device.
[0009]
The throttle body 105 is provided with a throttle sensor 104, which is one of operating condition measuring means of the internal combustion engine for detecting the opening of the electronically controlled throttle valve 105a, and a signal thereof is also output to the control unit 115. It has become so.
[0010]
The air taken into the collector 106 is distributed to each intake pipe 101 connected to each cylinder 107b of the internal combustion engine 107, and then is distributed to the combustion chamber of the cylinder 107b.
It is led to 107c.
[0011]
On the other hand, fuel such as gasoline is primarily pressurized from a fuel tank 108 by a fuel pump 109 and regulated to a constant pressure by a fuel pressure regulator 110, and secondarily pressurized to a higher pressure by a high-pressure fuel pump 111. To the common rail.
[0012]
The high-pressure fuel is injected into a combustion chamber 107c from an injector 112 provided in each cylinder 107b. The fuel injected into the combustion chamber 107c is ignited by an ignition plug 114 in response to an ignition signal whose voltage is increased by an ignition coil 113.
[0013]
Further, the cam angle sensor 116 attached to the camshaft of the exhaust valve outputs a signal for detecting the phase of the camshaft to the control unit 115. Here, the cam angle sensor may be attached to the camshaft on the intake valve side. Further, a crank angle sensor 117 is provided on the crankshaft axis to detect the rotation and phase of the crankshaft of the internal combustion engine, and the output is input to the control unit 115.
[0014]
Further, an air-fuel ratio sensor 118 provided upstream of the catalyst 120 in the exhaust pipe 119 detects the exhaust gas, and outputs a detection signal to the control unit 115.
[0015]
As shown in FIG. 2, a main part of the control unit 115 includes an MPU 203, an EP-ROM 202, a RAM 204, an I / OLSI 201 including an A / D converter, and the like, and measures (detects) an operating state of the internal combustion engine. Signals from various sensors including the airflow sensor 103 and the fuel pressure sensor 121, which are one of the means, are taken as inputs, and predetermined arithmetic processing is executed, and various control signals calculated as the arithmetic results are output. A predetermined control signal is supplied to each of the injectors 112, the ignition coil 113, and the like to execute fuel supply amount control and ignition timing control.
[0016]
Such a power unit is mounted on a vehicle in a state as shown in FIG. That is, the engine 301 generates power, and the generated power is transmitted to the transmission 303 via the clutch 302 in the manual transmission. The transmission 303 converts the rotation to a predetermined gear ratio, and further transmits power from the differential 304 on the downstream side to the wheels 305. In a manual transmission, the clutch 302 is operated by a driver, but in an automatic transmission, the control device controls power on / off having the same function as that of the clutch. Further, there is a type in which the shift and clutch operation are controlled by a control device while having the same mechanism as a manual transmission. In such a case, the intermittent power can be controlled arbitrarily by the control unit 308 of the transmission and the drive system.
[0017]
On the other hand, the power of the engine 301 is controlled by controlling the amount of intake air as described with reference to FIG. 1, but this is performed by the electronically controlled throttle 306, and the electronically controlled throttle 306 is arbitrarily controlled by the control unit 307. Is done.
[0018]
Next, FIG. 4 shows a schematic configuration of the electronically controlled throttle 306. The control unit 307 provides a drive signal to the motor 402. The motor 402 receives the drive signal, generates an operating torque, and applies a rotating torque to the shaft 401. The shaft 401 is connected to a throttle valve 403 which is a butterfly valve, and is rotatable together with the shaft 401. Further, the shaft 401 is also coupled to a spring 407, and is set so as to be balanced when the throttle valve 403 is at a predetermined angle. Therefore, when the operating torque generated by the motor 402 is controlled, the throttle valve can be operated to an arbitrary opening degree in which the operating torque and the reaction force of the spring 407 are balanced. The operated throttle valve 403 generates a clearance between the throttle valve 403 and the throttle body 406 according to the throttle opening. In the engine, the electronically controlled throttle is arranged so that the intake pipe is arranged in the front and rear directions in the figure, so that the intake air amount of the engine can be controlled according to the opening area of the clearance. From the above, it is possible to control the intake air amount of the engine by controlling the drive signal given to the electronically controlled throttle.
[0019]
Further, the operated throttle valve opening is transmitted to the sensor 405 via the lever 404. The sensor 405 detects the position of the lever 404 based on the resistance value of a resistor or the like, and outputs the throttle valve opening as an electric signal to an external device. Output to The output electric signal is input to the control unit 307.
[0020]
Subsequently, a method of controlling the electronically controlled throttle will be described with reference to FIG. The target throttle opening calculating section 501 indicates one function of control logic calculated in the control unit 307. That is, a target throttle opening is calculated based on the accelerator operation amount operated by the driver of the vehicle and the required engine state, and is delivered to the throttle actuator operation unit 502. The throttle actuator operation unit 502 controls the electronically controlled throttle to obtain the target throttle opening.
A drive signal is output to the control throttle 503. Here, the actual throttle opening described in FIG. 4 is received from the electronically controlled throttle, and the drive signal is adjusted so that the actual throttle opening becomes the target throttle opening. It is carried out. As a result, a quick and accurate target throttle opening can be realized.
[0021]
An example of the target throttle opening calculation performed by the target throttle opening calculator 501 will be described with reference to FIG. First, a target engine torque is calculated in block 1101 with an operation amount of an accelerator operated by a driver of a vehicle as an input. In addition to the output torque operated by the accelerator, an idling maintenance torque for maintaining the autonomous rotation of the engine is also required, and both of them are added up in a block 1102.
[0022]
Further, for example, when shifting the automatic transmission, there are various torque requests to reduce shift shock, and the target torque calculated in block 1102 is adjusted in block 1103 to calculate the final target torque. In response to this, the block 1104 calculates a target throttle opening to realize the target torque.
[0023]
As described above, the output of the engine can be arbitrarily controlled by controlling the intake air amount of the engine using the electronically controlled throttle. On the other hand, if any of the functions fails in the above-described system, it becomes impossible to control the output of the engine. An example of means for detecting such a situation will be described with reference to FIG. As described with reference to FIG. 5, the throttle actuator operation unit 502 outputs a drive signal so as to achieve a target throttle opening. However, if any part of this function fails, the actual throttle opening controls the control. Despite the operation, the actual opening degree is not reached. Therefore, in block 601, the target throttle opening and the actual throttle opening are input, and the two are compared to calculate the deviation. In block 602, a failure determination calculation is performed in response to the deviation. That is, when the actual throttle opening does not reach the target opening, the deviation becomes a value significantly larger than 0 or significantly smaller than 0. As described above, since the throttle actuator operation section performs closed loop control, a predetermined time is required for the actual throttle opening to coincide with the target throttle opening, and the target throttle opening and the actual throttle opening are required. The openings may not exactly match due to limitations in control performance. Therefore, in order to determine a failure based on the deviation, a failure is determined when a state in which the deviation is significantly larger than 0 or significantly smaller than, for example, a predetermined time has elapsed. Further, in addition to the description with reference to FIG. 6, a disconnection or a short-circuit that electrically disables transmission of each signal is detected to ensure safety.
[0024]
With the means described above, it is possible to detect when a series of systems controlling the electronically controlled throttle have failed.
[0025]
Next, a response when a failure is detected will be described. The failure indicates various states depending on the location where the failure occurred and the failure mode. Even if it is divided, while the driver of the vehicle desires that the engine output is small, the situation where the engine output is large is given a high risk because the acceleration given to the vehicle is larger than the acceleration intended by the driver, and is avoided. Is required. Such a state can be detected by detecting that the deviation obtained in the block 601 in FIG. 6 is larger than the target throttle opening by the actual throttle opening.
[0026]
For example, in the case of a mode in which the motor 402 always generates a driving torque in the opening direction, the failure mode can be avoided by stopping the supply of the driving signal and guiding the driving signal to a predetermined throttle opening degree by the spring 407. When the electronically controlled throttle bites foreign matter and is mechanically fixed in a region where the throttle valve opening is large, it may not be possible to recover by an electric operation. It goes without saying that such a state is designed to be avoided by a mechanical device, but a mechanical device that can completely deny the possibility of failure is unlikely. Therefore, assuming such a state, a method for avoiding a dangerous state by another means will be described below.
[0027]
First, there is a simple way to force the engine to stop. FIG. 7 shows an example of characteristics of a gasoline engine. Since it is assumed that the throttle valve is fixed, the throttle opening and the engine speed are characteristics when the engine speed is constant. The vertical axis is the torque generated by the engine, the horizontal axis is the air-fuel ratio, which is the ratio of fuel to the amount of intake air, the left side is rich, where the ratio of fuel amount to air amount is large, and the right side is lean, which is the opposite state. Is shown. When the intake air amount is constant and the air-fuel ratio is rich, it is equivalent to a large amount of supplied fuel, and the generated torque is proportional to the air-fuel ratio in a range where all the supplied fuel can be burned. On the rich side outside the range, the combustion becomes inadequate because the gasoline concentration in the combustion chamber is excessively high, and the generated torque decreases. On the other hand, on the lean side, the gasoline concentration in the combustion chamber is low, so that the combustion also becomes inadequate. When the gas becomes leaner than a certain region, the air-fuel mixture no longer burns, and the generated torque becomes zero.
[0028]
As understood from this characteristic, the engine output can be reduced by operating the supply air-fuel ratio lean or stopping the fuel supply when the throttle opening is larger than the target. Therefore, to forcibly stop the engine, the fuel supply may be stopped.
[0029]
As a method of lowering the output of the engine without stopping the engine, a method of operating the air-fuel ratio lean is also conceivable, but as described above, the operable range is limited, and the degree of freedom of operation is low. Unburned fuel due to combustion failure, catalyst
Since the catalyst 120 reacts and burns, the temperature of the catalyst 120 becomes high, which may lead to burning. Therefore, it is difficult to adopt a method of operating the air-fuel ratio lean.
[0030]
Here, consider a state in which the engine is forcibly stopped. The engine is usually the sole power source of the vehicle, and the power required to operate the vehicle is often supplied from the engine. For example, power steering, which facilitates the operation of the driver of the steering system, is a system in which the engine mechanically drives a hydraulic pump to generate hydraulic power, which is a power source. Is supplied to generate power. The air conditioner is supplied with power of a compressor for compressing a refrigerant from an engine. An oil pump for operating the lubrication system and a water pump for operating the cooling system for operating the engine properly are also powered by the engine. The pedaling force doubling device that assists the pedaling force of the brake is provided by the engine's suction negative pressure. Operate using.
[0031]
Such devices become inoperable because the power source is lost when the engine stops. Therefore, if the engine is forcibly stopped, these devices do not operate, causing inconvenience to the driver.
[0032]
Returning and organizing, the state to be avoided is a state in which the vehicle accelerates without following the driver's intention. Therefore, a method of avoiding a situation in which the vehicle accelerates without meeting the driver's intention while the engine output is large with respect to the driver's intention while avoiding the engine stop will be described below.
[0033]
As a method of avoiding acceleration of the vehicle, there is a method of cutting off the driving force transmission. Therefore, if the power transmission is stopped when the above-described failure is detected, the vehicle does not accelerate, and the above-described state can be avoided. The specific operation will be described with reference to FIG. First, the driver operates the accelerator while the system is in a normal state, and accordingly, the throttle is operated in the opening direction. The clutch is in the continuous state, and the engine output is increased (not shown) as the throttle is operated in the opening direction.
The vehicle is accelerated with the acceleration shown in FIG. Subsequently, a failure occurs in which the throttle valve is stuck at the operated throttle opening at the time shown in FIG. At this time, since the target throttle opening matches the actual throttle opening, the failure determination means described with reference to FIG. 6 does not detect a failure. If the driver performs the operation of returning the accelerator as shown in FIG. 12 after a further period of time, the throttle valve is operated in the closing direction in a state where there is no failure, but in this case, a failure occurs and Therefore, the throttle valve opening remains at the above-described degree. From this point, a state where the deviation described in FIG. 6 is large is detected, and a failure is detected with a predetermined determination time. At that moment, the clutch that had been in a continuous state is forcibly operated to be disconnected. When the clutch is disengaged, power is not transmitted to the vehicle, so that the acceleration of the vehicle decreases as shown in the figure.
[0034]
By the above operation, it is possible to avoid acceleration of the vehicle against the driver's intention.
[0035]
Next, the state and operation of the engine in such a state will be described. First, FIG. 9 is an example showing the relationship among the engine speed, the engine output torque, and the throttle valve opening. The line in the figure indicates the equal throttle valve opening. As shown in FIG. 9, the throttle valve opening is small at low rotation and low output torque, and conversely, the throttle valve opening is high at high rotation and high output torque. Take a large value. As described above, it is considered that the sticking of the throttle valve can occur at any opening degree. However, in the example described with reference to FIG. 12, a failure occurs in the state of high rotation and high output torque at the upper right of FIG. Is assumed. Since the output of the engine is the product of the engine output torque and the engine speed, the engine output is high when the throttle valve is fixed. If the clutch is disengaged in such a state, there is no load to be balanced with the engine output, and the engine output is consumed for increasing the engine speed. That is, when the clutch is disengaged, the engine speed increases, and the engine speed increases until the mechanical limit of the engine is exceeded, thereby destroying the engine.
[0036]
In order to avoid such a state, a method of stopping fuel supply when a predetermined engine speed is exceeded is adopted. The details will be described with reference to FIG. FIG. 10 shows the behavior of the engine speed and the state of fuel supply with time taken on the horizontal axis. Since the engine output is large, the engine speed is increasing while the fuel supply is being performed. Eventually, when the engine speed reaches the engine speed for fuel cut determination indicated by the dashed line in the figure, the supply of fuel is stopped, and the engine speed decreases accordingly. Next, when the engine speed reaches the fuel recovery determination indicated by another alternate long and short dash line, fuel supply is executed again. Therefore, the engine speed starts to increase. Eventually, the engine speed again reaches the speed for fuel cut determination, and the supply of fuel is stopped. Thus, the engine speed repeatedly rises and falls around a predetermined value, and does not reach the engine speed at which the engine is damaged.
[0037]
A method for applying such an operation to guide the engine speed to a desired value will be described below. FIG. 14 is a view similar to FIG. 10, and shows the behavior of the engine speed when the fuel cut rotation speed and the fuel recovery rotation speed are reduced with time as described in FIG. 10. . The engine rotational speed changes centering on a predetermined average rotational speed according to the fuel cut rotational speed and the fuel recovery rotational speed while repeatedly increasing and decreasing similarly to FIG. That is, if both the fuel cut speed and the fuel recovery speed are operated, the average engine speed can be operated accordingly. At this time, as described above, the engine output is the product of the engine output torque and the engine speed, and the engine output torque is low when the throttle opening is particularly large as understood from FIG. Since an approximately predetermined value is taken, an operation for reducing the engine speed can reduce the engine output.
[0038]
As described above, when the throttle valve is stuck at an opening with an engine output larger than the driver's intention, the drive system is disconnected to prevent the vehicle from accelerating and, at the same time, prevent the engine from being damaged. It is possible to reduce the engine output up to the engine output. In this state, since the engine is not stopped, the devices that operate using the engine as a power source as described above are not hindered from operating.
[0039]
As another method, it is conceivable to adjust the output of the engine by fuel supply operation without disconnecting the drive system.However, in this case, the degree of freedom of operation of the engine output in the fuel supply operation is limited, Since it takes time for the response, the operation involving disconnection of the drive system is more excellent in operability for avoiding the state.
[0040]
(Example 2)
In the first embodiment, it is assumed that the fixed opening of the throttle is always too large for the driver's intention. However, in a state where the driver requires a considerable engine output, there is no need to perform an operation to disconnect the clutch. FIG. 15 shows a determination flow based on such a concept.
[0041]
First, in step 1501, it is determined whether or not a failure has occurred in the throttle valve. If not, the flow ends without performing any special processing. If the throttle valve has failed, the routine proceeds to step 1502, where the actual engine output is compared with a target engine output determined by, for example, the accelerator operation amount of the driver, and a magnitude relationship is determined. When the actual engine output is higher than the target engine output, the power transmission is connected to prevent the vehicle acceleration from becoming larger than the driver's intention.
At 1503, a request to turn off output transmission is generated and passed to control of output transmission. On the other hand, when the actual engine output is equal to or smaller than the target engine output, the acceleration of the vehicle does not become larger than the driver's intention. Hand over to control.
[0042]
The operation of the flow described above will be described with reference to FIG. First, the sticking failure of the throttle valve continues to occur in advance, and it is detected that the throttle valve is in a failure state. The throttle valve opening is fixed at a predetermined relatively large value. In such a state, the vehicle is decelerating because the clutch is controlled to be disengaged as described above. The driver perceives that the vehicle is uniformly decelerating, but there may be cases where the driver wants to accelerate the vehicle under various environmental conditions. Then, he operates the accelerator as shown in the figure to indicate his intention to accelerate. In response to this, the target engine output becomes equal to or greater than the actual engine output. During that time, the driving force is transmitted to the vehicle through the clutch and the vehicle is accelerated. When the driver no longer desires the acceleration state, an operation of returning the accelerator as shown in the figure is performed. In response to this, the target engine output becomes smaller than the actual engine output, so the clutch is disengaged again, and the vehicle shifts to a deceleration state.
[0043]
As described above, when the above operation is performed, it is not necessary to stop the engine even when a failure occurs, and in a limited state, the vehicle can be operated to accelerate or decelerate according to the driver's intention. .
[0044]
(Example 3)
In the second embodiment, the control is realized by connecting and disconnecting the clutch. However, by further combining the operation of supplying and stopping the fuel, fine control can be performed. This control method will be described with reference to FIG. The control flow of FIG. 19 starts when a failure of the throttle valve is detected. First, the target torque calculation function 1901 calculates a target torque intended by the driver from the accelerator operation amount of the driver and the engine speed. On the other hand, the actual torque provisional calculation function 1903 calculates a provisional value of the torque actually generated by the engine from the actual throttle opening and the engine speed. Here, the provisional value is the torque output by the engine when the fuel supply is not stopped at all. The fuel supply calculation function 1902 receives the calculation results of the target torque calculation function 1901 and the actual torque provisional calculation function 1903, determines fuel supply and stops, and outputs the result. Specifically, if the engine output torque when the fuel supply is continued is larger than the target torque, it is determined that the fuel supply is stopped so that the actual torque is closest to the target torque. For example, as described with reference to FIG. 14, the determination engine speed for the fuel cut is calculated, and when the actual engine speed is higher than the engine speed for the fuel cut, the supply of the fuel is stopped. Next, the actual torque calculation function 1904 calculates the final actual torque by inputting the fuel supply / stop determination and the provisional actual torque value. For example, when the fuel supply is completely stopped, the output torque is 0. When the fuel supply is not stopped, the output torque is the same as the provisional value calculated by the actual torque provisional calculation function 1903. Further, as shown in FIG. 14, when the supply and stop of the fuel are repeated in a short cycle, the engine output torque averaged over a predetermined time may be recognized. The clutch engagement / disconnection calculation function 1905 compares the calculation result of the actual torque calculation function 1904 with the target engine torque, and determines that the clutch is to be continued when the target engine output is equal to or smaller than the actual torque, and is determined to be disconnected otherwise. Do.
[0045]
By the above processing, the transmission of power is intermittently performed according to the driver's intention based on the actual engine output state due to the supply and stop of the fuel and the opening degree of the sticking of the throttle valve. The vehicle can be controlled more finely.
[0046]
In the above description of FIG. 19, torque is used as a parameter of the engine output. However, this shows an embodiment in a case where it is convenient to perform processing in the order of torque in general engine control. For this reason, a method of performing processing using the engine output is naturally conceivable.
[0047]
(Example 4)
As shown in FIG. 3, in many vehicle controls, a system for controlling the engine system is one highly independent system, and similarly, the control of the transmission and the drive system is also one highly independent system. Usually it is. This is because the information input from the sensors is processed efficiently and efficiently in each system, and it is necessary to drive the control target while closely cooperating with each other. Therefore, it is reasonable to separate the control unit for controlling the engine from the control unit for the transmission and the drive system.
[0048]
However, when the operation described with reference to FIG. 19 in the third embodiment is performed, the operation extends over the control unit for controlling the engine and the control unit for the transmission and the drive system. A method for implementing the present invention with such a configuration will be described below.
[0049]
First, as shown in FIG. 3, a communication line 309 is provided between a control unit 307 for engine control and a control unit 308 for a transmission and a drive system, and necessary information is communicated between the control units. Communication is performed at predetermined time intervals, and both control units recognize each other's information at short predetermined time intervals and perform good cooperative control. Setting such communication means is already known. FIG. 17 shows an example of information communicated by both control units. The upper part shows information items from the engine control unit to the transmission control unit, and the lower part shows information items from the transmission control unit to the engine control unit. First, in the upper part, the engine control unit transmits the driver's required torque and clutch disconnection request calculated by the method described with reference to FIG. Thus, the request of the engine side for the clutch intended in FIG. 19 is transmitted. On the other hand, the transmission control unit transmits a torque operation request value to the engine side to reduce the shock of the vehicle at the time of shifting, or comprehensively processes the aforementioned clutch disengagement request, and as a result, the clutch disengagement And send the status.
[0050]
FIG. 16 shows an example of processing in the transmission control unit. The target gear ratio calculation function 1601 calculates a target gear ratio from the driver's required torque and the vehicle speed shown in FIG. It is advantageous from the viewpoint of fuel efficiency that the gear ratio has a low value at each vehicle speed, but when the driver intends to accelerate, the gear ratio is increased to secure the acceleration. Such determination and processing are performed by the target gear ratio calculation function 1601. The gear ratio operation calculating function 1602 generates a signal for operating the transmission actuator in response to the result of the target gear ratio calculating function 1601, while controlling the torque applied to the engine to minimize the torque fluctuation to the vehicle during gear shifting. The request value is calculated and requested to the engine side as described in FIG. On the other hand, in the clutch on / off calculation function 1603, the clutch is released, for example, when the vehicle is in a stopped state, and the operation of the drive system is precisely controlled based on the vehicle speed and the driver's required torque. As described above, when there is a clutch disconnection request from the engine control side, a final clutch disconnection determination is made so as to realize the request, and an operation signal is output to the actuator. Further, the interruption determination is transmitted to the engine side as described with reference to FIG.
[0051]
FIG. 18 shows a specific example of the clutch disconnection determination. When the driver's required torque is 0 and the vehicle speed is 0, there is no need to transmit power, so the clutch is disengaged, or the shift lever operated by the driver shifts to the neutral position. At some point, the clutch is disengaged because the driver does not intend to engage the power. Further, the clutch is also disconnected when there is a clutch disconnection request from the engine side as described in FIG. The process of disengaging the clutch is valid when any of the above clutch disengagement requests is satisfied, and it is determined that the clutch is to be continued when none of the requests is satisfied.
[0052]
As described above, when the control unit for engine control and the control unit for the transmission and the drive system are separate units, the above-described method is employed, and the control of both units is coordinated. The operation as shown in FIG. 19 can be realized.
[0053]
As described above, the description has been made on the assumption that a gasoline engine is used as the power source of the vehicle. However, an equivalent phenomenon occurs in a diesel engine, and equivalent processing can be performed. FIG. 8 is an example showing the engine generated torque when the intake air amount is manipulated when the supplied fuel amount is fixed in the diesel engine. In the diesel engine, the combustible air-fuel ratio exists widely on the lean side, and therefore, the intake air amount of the normal engine is not substantially limited, and the engine output is controlled by controlling the fuel supply amount. If the intake air amount is reduced in such a state, the generated torque has only a small sensitivity in a predetermined range, and slightly decreases. If the intake air amount is limited beyond a certain point, the supplied air amount can no longer supply oxygen enough to burn the entire fuel supply amount, and the generated torque decreases almost in proportion to the intake air amount. If the intake air amount is further reduced, combustion no longer occurs normally, and the generated torque becomes extremely small.
[0054]
Therefore, a failure mode in which a large amount of fuel is supplied against the driver's intention in a diesel engine is a failure mode equivalent to a throttle valve opening being stuck at a predetermined value in a gasoline engine. To adjust the engine output by supplying and stopping, instead of adjusting the fuel supply amount as in the gasoline engine, a method of executing and stopping the fuel supply itself can be considered, or there is a means for controlling the intake air amount. For example, the same operation can be performed by controlling this. Therefore, the operation described in FIG. 12 and the processing described in FIG. 19 can be applied to the diesel engine.
[0055]
Although the embodiment in which the internal combustion engine is used as the power source of the vehicle has been described above, more generally, there is a vehicle having a power source other than the internal combustion engine such as a motor. However, in any case, a means for controlling the output of the power mainly based on the driver's operation intention is provided, and as long as the means exists, the possibility that the failure will occur cannot be denied. In such a case, similar effects can be obtained by applying the present invention.
[0056]
【The invention's effect】
As can be understood from the above description, the present invention has an effect that, even when the device for controlling the output of the internal combustion engine fails, the operation of the device for securing power from the internal combustion engine is maintained without stopping the internal combustion engine. Thus, acceleration and deceleration of the vehicle according to the driver's intention can be performed. As a result, it is possible to reflect the driver's intention to avoid danger, such as avoiding stopping the vehicle at an intersection or an expressway and continuing driving of the vehicle to a nearby maintenance yard.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a direct injection internal combustion engine control system according to an embodiment of the present invention.
FIG. 2 is an internal configuration diagram of the internal combustion engine control device of FIG. 1;
FIG. 3 is a diagram illustrating a configuration of a vehicle.
FIG. 4 is a diagram illustrating the configuration of an electronically controlled throttle.
FIG. 5 is a diagram illustrating a control operation unit of the electronically controlled throttle.
FIG. 6 is a block diagram illustrating processing for determining a failure.
FIG. 7 is a diagram illustrating characteristics of a gasoline engine.
FIG. 8 is a diagram illustrating characteristics of a diesel engine.
FIG. 9 is a diagram illustrating characteristics of a gasoline engine.
FIG. 10 is a diagram illustrating an operation of engine control.
FIG. 11 is a block diagram illustrating an operation of engine control.
FIG. 12 is a diagram for explaining the operation of one embodiment of the present invention.
FIG. 13 is a view for explaining the operation of one embodiment of the present invention.
FIG. 14 is a view for explaining the operation of one embodiment of the present invention.
FIG. 15 is a flowchart illustrating the operation of one embodiment of the present invention.
FIG. 16 is a block diagram illustrating the operation of one embodiment of the present invention.
FIG. 17 is a diagram of parameters for explaining an embodiment of the present invention.
FIG. 18 is a logic diagram explaining the operation of one embodiment of the present invention.
FIG. 19 is a block diagram illustrating the operation of one embodiment of the present invention.
[Explanation of symbols]
101: intake pipe, 102: air cleaner, 103: air flow sensor (air flow meter), 104: throttle sensor, 105, 406: throttle body, 106: collector, 107: in-cylinder injection internal combustion engine, 108: fuel tank, 109 ... Fuel pump, 111 ... High pressure fuel pump, 112 ... Injector, 113 ... Ignition coil, 114 ... Ignition plug, 115 ... Control unit, 116 ... Cam angle sensor, 117 ... Crank angle sensor, 118 ... Air-fuel ratio sensor, 119 ... Exhaust pipe , 120: catalyst, 121: fuel pressure sensor, 201: I / O LSI, 202: EP-ROM, 203: MPU, 204: RAM, 301: engine, 302: clutch, 303: transmission, 304: differential, 305: Wheels, 306, 503 ... Electric control slot Torr: 307: control unit for engine control, 308: control unit for transmission and drive system, 309: communication line, 401: shaft, 402: motor, 403: throttle valve, 404: lever, 405: sensor, 501: Target throttle opening calculation unit, 502: throttle actuator operation unit, 1601: target gear ratio calculation function, 1602: gear ratio operation calculation function, 1603: clutch disconnection calculation function, 1901: target torque calculation function, 1902: fuel supply calculation function , 1903... Actual torque provisional calculation function, 1904... Actual torque calculation function, 1905.

Claims (5)

An internal combustion engine, an output control device for the internal combustion engine, a device for transmitting the output of the internal combustion engine to wheels, a device for intermittently transmitting the output of the internal combustion engine to the wheels, and an output control device for the internal combustion engine A device for interrupting the transmission of the output of the internal combustion engine to the wheels when a failure of the output control device of the internal combustion engine is detected. A safety control device for a vehicle, characterized in that: 2. The apparatus according to claim 1, further comprising a device for controlling a rotation speed of the internal combustion engine by supplying and stopping fuel, and transmitting a power of the internal combustion engine to wheels when a failure of the output control device of the internal combustion engine is detected. The transmission of the output of the internal combustion engine to the wheels is interrupted by a device for interrupting the rotation of the internal combustion engine, and the rotation speed of the internal combustion engine falls within a predetermined range by a device for controlling the rotation speed of the internal combustion engine by supplying and stopping fuel. Control device for a vehicle, characterized in that the control is performed in the following manner. 2. The apparatus according to claim 1, further comprising a device for detecting a required output of the driver, comparing the required output of the driver with the output of the internal combustion engine, and determining whether the output of the internal combustion engine is transmitted to the wheels. A safety control device for a vehicle. Claim 2 has a device for detecting the required output of the driver, and compares the required output of the driver with the output of the internal combustion engine to determine whether to supply or stop the fuel. A vehicle safety control device that compares an output with a driver's required output to determine whether or not transmission of the output of the internal combustion engine to wheels is intermittent. The safety control device for a vehicle according to claim 4, wherein the device that controls the intermittent transmission of the output of the internal combustion engine to the wheels and the device that detects a failure of the output control device of the internal combustion engine exist in different mechanisms. A safety control device for a vehicle, wherein the device for detecting a failure of the output control device of the internal combustion engine supplies a request to cut off the transmission of power to the device for controlling the intermittent by communication.

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