JP2007055474A - Automobile and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more appropriately start vehicle stop holding control holding a stopping state and more appropriately release the vehicle stop holding control irrespective of subsequent brake operation by a driver. <P>SOLUTION: When either of accelerator openings A1 or A2 reaches a value lower than an accelerator off threshold value Aref 1, the value of a vehicle speed V is 0, and a brake is turned on, the vehicle stop holding control is started (S120 to S150), and when both of accelerator openings A1 and A2 become larger than the accelerator on-threshold value, the vehicle stop holding control is released. The vehicle stop holding control can be more quickly and more appropriately started and the vehicle stop holding control can be more surely and more appropriately released thereby. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an automobile and a control method thereof.

  Conventionally, this type of automobile is controlled by the vehicle when the vehicle speed is 0 and the brake is on, or when the vehicle speed is 0 and the brake hold switch is on, regardless of the driver's subsequent brake operation. There has been proposed one that performs stop holding control to generate power and hold the stop state (see, for example, Patent Document 1). In this automobile, when the stop state is maintained, when the accelerator operation amount reaches a predetermined offset amount or later, it is determined that the accelerator operation is performed, and the stop holding control is released.

There has also been proposed an automobile that detects a driver's accelerator operation amount using two accelerator sensors (see, for example, Patent Document 2). In this automobile, when one accelerator sensor fails, the other accelerator sensor is used to control the accelerator opening.
JP 2004-75055 A JP 2001-260699 A

  Considering an automobile that performs the above-described stop holding control using two accelerator sensors, it is determined whether to start the stop holding control or whether to cancel the stop holding control depending on which accelerator sensor output is used. Depending on the case, the stop holding control may not be started or the release of the stop holding control may be delayed. In addition, in an automobile using two accelerator sensors, the zero correction and learning of the accelerator sensor are often performed, but if the zero correction or learning is performed during the stop holding control, the stop holding control is performed. In some cases, the determination of the release of the vehicle changes and the vehicle stop holding control is not properly released. In particular, when the zero point correction or learning of the accelerator sensor is performed when the driver kicks up the accelerator pedal at any time, the stop holding control cannot be properly canceled.

  One object of the automobile and the control method thereof according to the present invention is to more appropriately start the stop holding control for holding the stop state regardless of the driver's subsequent brake operation. Another object of the automobile and the control method thereof according to the present invention is to more appropriately release the stop holding control. Furthermore, an object of the automobile and its control method of the present invention is to stabilize the behavior of the vehicle immediately after the stop holding control is canceled.

  In order to achieve at least a part of the above object, the automobile of the present invention and the control method thereof employ the following means.

The automobile of the present invention
Braking force applying means for applying a braking force to the vehicle based on the driver's braking operation and capable of applying the braking force to the vehicle regardless of the driver's braking operation;
Two different accelerator operation amount detecting means for detecting the driver's accelerator operation amount,
When a predetermined start condition including a condition that the accelerator operation amount detected by one of the two accelerator operation amount detection means is less than the accelerator-off threshold is satisfied while the vehicle is stopped, the driver's A stop holding control is performed to control the braking force applying means so that the braking force is applied and the stop state is maintained regardless of the brake operation, and the two accelerators are executed during the stop holding control. The braking force so that the stop holding control is released when a predetermined release condition is satisfied, including a condition that an accelerator operation amount detected by at least one of the operation amount detection means is equal to or greater than an accelerator-on threshold. Stop holding control means for controlling the giving means;
It is a summary to provide.

  In the automobile of the present invention, the condition that the accelerator operation amount detected by one of the two different accelerator operation amount detection means for detecting the driver's accelerator operation amount in a state where the vehicle is stopped is less than the accelerator off threshold. The braking force applying means capable of applying a braking force to the vehicle is controlled so that the braking force is applied and the stop state is maintained regardless of the driver's braking operation when a predetermined start condition including one is satisfied. Carry out stop holding control. Thereby, it is possible to avoid the stop holding control from being executed and to execute the stop holding control more quickly and appropriately. Further, there is a predetermined release condition including a condition that the accelerator operation amount detected by at least one of the two accelerator operation amount detection means during the stop holding control is equal to or more than an accelerator on threshold. The braking force applying means is controlled so that the stop holding control is canceled when it is established. Thereby, it is possible to avoid that the stop holding control is not released and to release the stop holding control more quickly and appropriately.

  Such an automobile of the present invention may be provided with vehicle speed detecting means for detecting a vehicle speed, and the predetermined start condition may be a condition including a condition for detecting a vehicle speed of value 0 by the vehicle speed detecting means. In addition, a brake operation amount detection unit that detects a brake operation amount of the driver is provided, and the predetermined start condition includes one condition that a brake operation amount detected by the brake operation detection unit is less than a brake-off threshold value. It can also be a condition.

  Further, in the automobile of the present invention, the predetermined release condition is a condition including one condition that both of the accelerator operation amounts detected by both of the two accelerator operation detecting means are equal to or greater than an accelerator on threshold value. It can also be. By so doing, it is possible to avoid malfunction and to cancel the stop holding control more appropriately compared to the case where the stop holding control is canceled only by turning on the accelerator by one accelerator operation amount detection means.

  Furthermore, in the automobile of the present invention, when the predetermined start condition is satisfied when the accelerator operation amount detected by one of the two accelerator operation detecting means becomes less than the accelerator off threshold, the two An accelerator operation amount correction unit that corrects each accelerator operation amount detected by the accelerator operation detection unit based on an accelerator off threshold value may be provided. In this way, the accelerator operation amount detected by each accelerator operation amount detection means can be made more appropriate, and the stop holding control can be canceled or the stop holding control can be started more appropriately next time. it can.

  Alternatively, in the vehicle of the present invention, learning means for learning the accelerator operation amount value 0 based on the respective accelerator operation amounts detected by the two accelerator operation amount detection means, and the predetermined start condition is established. Learning stop means for prohibiting learning by the learning means when the stop holding control is being executed by the stop holding control means may be provided. In this way, it is possible to detect the accelerator operation amount more appropriately and to prevent the stop holding control from being canceled inappropriately by learning the accelerator operation amount performed based on an inadvertent driver's operation. Can do.

  Further, in the automobile of the present invention, when the stop holding control is released until the predetermined stop condition is satisfied after the stop holding control is released by the stop holding control means and the driving force means capable of outputting the driving force for traveling. If not, the required driving force required for the vehicle is set with a first relationship with respect to the accelerator operation amount detected by one of the two accelerator operation amount detection means, and when the stop holding control is released, Requested driving for setting the required driving force with a second relationship in which the required driving force tends to be smaller than the first relationship with respect to the accelerator operating amount detected by one of the two accelerator operating amount detecting means. A force setting means; and a drive control means for controlling the driving force means so that a driving force based on the set required driving force is output. . In this way, it is possible to avoid that the driving force means is controlled by setting an unexpectedly excessive requested driving force when the stop holding control is released. As a result, the behavior of the vehicle immediately after canceling the stop holding control can be stabilized. In this case, the second relationship may be a relationship in which the required driving force is set smaller than the first relationship in a range where the detected accelerator operation amount is small. In this way, a small required driving force is set with respect to a small accelerator operation amount and the driving force means is controlled, so that the driver's unexpected vehicle behavior can be suppressed.

  The automobile of the present invention further comprises control execution instruction means for instructing execution of the stop holding control based on a driver's operation, wherein the stop holding control means is instructed to execute the stop holding control by the control execution instruction means. The vehicle stop holding control may be executed when the predetermined start condition is satisfied in a state where the vehicle is stopped. If it carries out like this, stop holding control can be performed based on a driver's intention.

The method for controlling an automobile of the present invention includes:
Two different accelerators for detecting the driver's accelerator operation amount and braking force applying means for applying a braking force to the vehicle based on the driver's brake operation and applying the braking force to the vehicle regardless of the driver's brake operation A control method for an automobile comprising an operation amount detection means,
When a predetermined start condition including a condition that the accelerator operation amount detected by one of the two accelerator operation amount detection means is less than the accelerator-off threshold is satisfied while the vehicle is stopped, the driver's A stop holding control is performed to control the braking force applying means so that the braking force is applied and the stop state is maintained regardless of the brake operation, and the two accelerators are executed during the stop holding control. The braking force so that the stop holding control is released when a predetermined release condition is satisfied, including a condition that an accelerator operation amount detected by at least one of the operation amount detection means is equal to or greater than an accelerator-on threshold. It is characterized by controlling the applying means.

  In this automobile control method of the present invention, the accelerator operation amount detected by one of the two different accelerator operation amount detection means for detecting the driver's accelerator operation amount with the vehicle stopped is less than the accelerator off threshold. Braking force applying means capable of applying a braking force to the vehicle so that the braking force is applied and the stop state is maintained regardless of the driver's braking operation when a predetermined start condition including the following condition is satisfied Stop holding control for controlling the vehicle is executed. Thereby, it is possible to avoid the stop holding control from being executed and to execute the stop holding control more quickly and appropriately. Further, there is a predetermined release condition including a condition that the accelerator operation amount detected by at least one of the two accelerator operation amount detection means during the stop holding control is equal to or more than an accelerator on threshold. The braking force applying means is controlled so that the stop holding control is canceled when it is established. Thereby, it is possible to avoid that the stop holding control is not released and to release the stop holding control more quickly and appropriately.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of the configuration of an automobile 20 as an embodiment of the present invention. The vehicle 20 of the embodiment is configured as a front-wheel drive vehicle in which the power from the engine 22 is changed by the automatic transmission 24 and output to the front wheels 34a and 34b via the differential gear 32, and the left and right front and rear wheels 34a to 34d are arranged. A brake actuator 40 for controlling the hydraulic pressure to the brake wheel cylinders 36a to 36d, a brake electronic control unit (hereinafter referred to as a brake ECU) 60 for driving and controlling the brake actuator 40, and a vehicle control for controlling the entire vehicle And an electronic control unit 70. The engine 22 is controlled by an engine electronic control unit (hereinafter referred to as engine ECU) 23, and the automatic transmission 24 is controlled by an automatic transmission electronic control unit (hereinafter referred to as ATTEC) 25.

  As shown in FIG. 2, the brake actuator 40 includes a front wheel brake actuator 41 and a rear wheel brake actuator 51. The front wheel brake actuator 41 is connected via a supply oil passage 42 to a brake master cylinder 90 that generates hydraulic pressure (master cylinder pressure) in the brake oil based on a driver's operation of the brake pedal 85, and a pressure increase / decrease oil passage. The left and right holding solenoid valves 44a and 44b connected to the brake wheel cylinders 36a and 36b of the front wheels 34a and 34b through 43a and 43b, and the brake wheel cylinders of the front wheels 34a and 34b through the pressurizing oil passages 43a and 43b. 36a, 36b and pressure reducing solenoid valves 46a, 46b connected to the reservoir 47 via the pressure reducing oil passage 45, and an oil pump 48 for pressurizing the oil in the reservoir 47 and supplying it to the supply oil passage 42. Prepare. In addition, two backflow prevention valves 49a and 49b are provided upstream and downstream of the oil pump 48 to prevent backflow. The holding solenoid valves 44a and 44b are configured as normally opened solenoid valves that are closed when energized (on), and the cylinder hydraulic pressure of the brake wheel cylinders 36a and 36b is maintained even when the solenoid valves 44a and 44b are turned on and closed. A check valve is provided for returning the brake oil to the supply oil passage 42 side when the oil pressure is higher than the supply oil passage 42 side. The decompression solenoid valves 46a and 46b are configured as normally closed solenoid valves that are opened when energized (on). Like the front wheel brake actuator 41, the rear wheel brake actuator 51 is connected to the brake master cylinder 90 via a supply oil passage 52 and brakes of the rear wheels 34c and 34d via pressure increase / decrease oil passages 53a and 53b. The left and right holding solenoid valves 54a, 54b connected to the wheel cylinders 36c, 36c, and the pressure reducing oil passages are connected to the brake wheel cylinders 36c, 36d of the rear wheels 34c, 34d through the pressure increasing / decreasing oil passages 53a, 53b. Pressure reduction solenoid valves 56a and 56b connected to the reservoir 57 via 55, an oil pump 58 that pressurizes the oil in the reservoir 57 and supplies it to the supply oil passage 52, and two backflow prevention valves 59a and 59b. . The holding solenoid valves 54a and 54b and the pressure reducing solenoid valves 56a and 56b of the rear wheel brake actuator 51 have the same configuration as the holding solenoid valves 44a and 44b and the pressure reducing solenoid valves 46a and 46b of the front wheel brake actuator 41. The following description of the operation of the front wheel brake actuator 41 is the same as the operation of the rear wheel brake actuator 51. The operation of the front wheel brake actuator 41 will be briefly described below.

  When the driver depresses the brake pedal 85 with all of the holding solenoid valves 44a and 44b and the pressure reducing solenoid valves 46a and 46b turned off (the state shown in FIG. 2), the master pressure corresponding to the depression is applied to the brake master cylinder 90. As a result, the brake oil is supplied to the brake wheel cylinders 36a and 36b via the supply oil passage 42, the holding solenoid valves 44a and 44b, and the pressure increase / decrease oil passages 43a and 43b, and the cylinder hydraulic pressure of the brake wheel cylinders 36a and 36b is increased. The braking force according to the cylinder oil pressure is applied to the front wheels 34a and 34b. When the driver returns the brake pedal 85 in this state, the brake oil in the brake wheel cylinders 36a and 36b is supplied to the brake master cylinder 90 via the pressure-increasing / depressurizing oil passages 43a and 43b, the holding solenoid valves 44a and 44b, and the supply oil passage 42. And the braking force applied to the front wheels 34a and 34b is released by reducing the cylinder oil pressure accordingly. The front wheel brake actuator 41 can hold the cylinder hydraulic pressure of the brake wheel cylinders 36a and 36b by turning on the holding solenoid valves 44a and 44b in addition to the normal operation. At this time, if the pressure reducing solenoid valves 46a and 46b are turned on (opened), the brake oil in the brake wheel cylinders 36a and 36b is supplied through the pressure increasing / decreasing oil passages 43a and 43b, the pressure reducing solenoid valves 46a and 46b, and the pressure reducing oil passage 45. The cylinder oil pressure of the brake wheel cylinders 36a and 36b can be reduced by being guided to the reservoir 47. The degree to which the cylinder hydraulic pressure is reduced can be adjusted by the time during which the pressure reducing solenoid valves 46a and 46b are turned on (opened). Further, by driving the oil pump 48, the pressurized brake oil is supplied to the brake wheel cylinders 36a and 36b via the supply oil passage 42, the holding solenoid valves 44a and 44b, and the pressure increasing / decreasing oil passages 43a and 43b. The cylinder hydraulic pressure of the brake wheel cylinders 36a and 36b can be increased. At this time, the holding solenoid valves 44a and 44b can be turned on (closed) to stop the pressurization of the cylinder hydraulic pressure. It can be adjusted according to the time until closing. When the holding solenoid valves 44a and 44b are turned on (closed), the state is the same as the state in which the cylinder hydraulic pressure is held. Therefore, the pressure can be reduced by turning on (opening) the pressure reducing solenoid valves 46a and 46b. In other words, the oil pressure of the brake wheel cylinders 36a and 36b can be freely adjusted by driving the oil pump 48 and turning on and off the holding solenoid valves 44a and 44b and the pressure reducing solenoid valves 46a and 46b. Of course, since the holding solenoid valves 44a and 44b and the pressure reducing solenoid valves 46a and 46b can be turned on and off independently, the cylinder hydraulic pressures of the brake wheel cylinders 36a and 36b can be freely adjusted individually.

  The valves 44a, 44b, 46a, 46b, 54a, 54b, 56a, 56b and the oil pumps 48, 58 of the brake actuator 40 are driven and controlled by the brake ECU 60. The brake ECU 60 inputs signals such as a wheel speed from a wheel speed sensor (not shown) attached to the left and right front and rear wheels 34a to 34d through a signal line (not shown) and a steering angle from a steering angle sensor (not shown). Anti-lock brake system function (ABS) that prevents any of the left and right front and rear wheels 34a to 34d from slipping due to locking when the brake pedal 85 is depressed, or a driving wheel when the driver depresses the accelerator pedal 83 Traction control (TRC) for preventing the front wheels 63a and 63b from slipping due to idling, posture holding control (VSC) for holding the posture while the vehicle is turning, and the like are performed. The brake ECU 60 communicates with the vehicle control electronic control unit 70, and drives and controls the brake actuator 40 by a control signal from the vehicle control electronic control unit 70.

  The vehicle control electronic control unit 70 is configured as a microprocessor centered on the CPU 72. In addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port (not shown), and And a communication port. The vehicle control electronic control unit 70 has two different types of signals for detecting the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 for detecting the operation position of the shift lever 81, and the depression amount of the accelerator pedal 83. Axel opening A1, A2 from the accelerator sensors 84a, 84b, brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, a vehicle speed V from the vehicle speed sensor 88, and a climbing slope installed near the driver's seat A brake hold signal from a brake hold switch 89 for instructing execution of stop holding control for holding the brake even when the brake pedal 85 is returned at the start of the road, a pressure sensor 92 attached to the brake master cylinder 90 Such as brake pressure Pb is input via the input port. The vehicle control electronic control unit 70 exchanges various control signals and data with the engine ECU 23, the ATECU 25, and the brake ECU 60.

  Next, the operation of the automobile 20 of the embodiment configured as described above, particularly the operation when the driver starts on the uphill road with the brake hold switch 89 turned on will be described. FIG. 3 is a flowchart showing an example of a stop holding start control routine executed by the vehicle control electronic control unit 70, and FIG. 4 shows an example of a stop holding release control routine executed by the vehicle control electronic control unit 70. It is a flowchart. These routines are repeatedly executed after the brake hold switch 89 is turned on. Hereinafter, the stop holding start control and the stop holding release control will be described in order.

  When the stop holding start control routine is executed, first, the CPU 72 of the vehicle control electronic control unit 70 first determines the accelerator pedal positions A1 and A2 from the two accelerator sensors 84a and 84b and the brake pedal position of the brake pedal position sensor 86. Processing for inputting data necessary to start the stop holding control such as the BP, the vehicle speed V from the vehicle speed sensor 88, and the stop holding execution flag Fstop is performed (step S100). Here, the stop holding execution flag Fstop is set to a value of 1 when the stop holding control is started by this routine, and is set to a value of 0 when the stop holding control is released by the stop holding release control routine.

  When the data is input in this manner, it is determined whether or not the stop holding execution flag Fstop is 0 (step S110), and whether one of the accelerator openings A1 and A2 is less than the accelerator-off threshold Aref1 for determining whether the accelerator is off ( In step S120, it is determined whether or not the vehicle speed V is 0 (step S130) and whether or not the brake is off (step S140). When the stop holding execution flag Fstop is a value 1, since the stop holding control has already been started, it is determined that it is unnecessary to start the control again, and this routine is finished. When accelerator opening A1 and A2 are both greater than or equal to accelerator off threshold Aref1, accelerator pedal 83 is depressed by the driver, and the driver has no intention to stop, so it is determined that there is no need to start stop holding control. Then, this routine ends. When the vehicle speed V is not 0 or when the brake is not on, it is determined that there is no need to start the stop holding control because the driver does not intend to stop, and this routine is finished.

  When the stop holding execution flag Fstop is 0, one of the accelerator openings A1 and A2 is less than the accelerator off threshold Aref1, the vehicle speed V is 0 and the brake is off, the brake wheel cylinders 36a to 36d While holding the cylinder pressure (step S150), a value 1 is set to the stop holding execution flag Fstop (step S160). Thus, even if the driver subsequently returns the brake pedal 85, the brake is maintained, so that the stopped state is maintained. Here, the holding of the brake wheel cylinders 36a to 36d can be performed by turning on (closing) the holding solenoid valves 44a, 44b, 54a, 54b. Specifically, the control signal is transmitted from the vehicle control electronic control unit 70 to the brake ECU 60, and the brake ECU 60 turns on the holding solenoid valves 44a, 44b, 54a, 54b based on the control signal.

  Then, the input accelerator opening A1 and A2 are corrected based on the accelerator-off threshold Aref1 (step S170), and the zero point learning flag Fa is set to a value 1 in order to inhibit the zero opening learning of the accelerator opening A1 and A2. After setting (step S180), this routine is terminated. Here, the reason why the accelerator openings A1 and A2 are corrected based on the accelerator-off threshold value Aref1 is to perform the determination when canceling the stop holding control and the determination when starting the next stop holding control more appropriately. . Specifically, the accelerator openings A1 and A2 are corrected by correcting the accelerator openings A1 and A2 so that both the accelerator openings A1 and A2 coincide with the accelerator-off threshold Aref1, or by turning off the accelerator openings A1 and A2. This can be done by correcting the opening to be slightly smaller than the threshold value Aref1. Further, when starting the stop holding control, the zero point learning of the accelerator openings A1 and A2 is normally prohibited by an operation such as the driver kicking up the brake pedal 85 while the stop holding control is being executed. By learning from the zero point that has a negative opening to the zero point, it becomes inappropriate to determine whether to cancel the stop holding control, or inappropriate to determine the start of the next stop holding control. This is to prevent occurrence of a case. Zero point learning of the accelerator openings A1 and A2 will be described later.

  Next, cancellation of the stop holding control will be described. When the stop holding release control routine of FIG. 4 is executed, the CPU 72 of the vehicle control electronic control unit 70 first needs to release the stop holding control such as the accelerator openings A1 and A21 and the stop holding execution flag Fstop. Data is input (step S200), whether or not the stop holding execution flag Fstop is a value 1 (step S210), and whether or not the accelerator openings A1 and A2 are both greater than an accelerator on threshold Aref2 for determining accelerator on ( Step S220) is determined. When the stop holding execution flag Fstop is 0, the stop holding control has already been released. Therefore, it is determined that it is unnecessary to release the control again, and this routine is terminated. When both the accelerator opening A1 and A2 are equal to or lower than the accelerator-on threshold Aref2, it is determined that the driver does not depress the accelerator pedal 83 clearly and the driver does not intend to start, and the stop holding control is canceled. It is determined that it should not be performed, and this routine is terminated.

  When the stop holding execution flag Fstop is a value 1 and both the accelerator openings A1 and A2 are larger than the accelerator on threshold Aref2, the holding solenoid valves 44a, 44b, 54a and 54b are turned off (opened) and the brake wheel cylinders 36a to 36d are turned on. In addition to releasing the cylinder pressure (step S230), the stop holding execution flag Fstop is set to 0 (step S240), and the zero point learning flag Fa is set to release the prohibition of the zero opening learning of the accelerator openings A1 and A2. The value 0 is set (step S250), and this routine is terminated. As a result, the brake is released and the vehicle can start with the driving force corresponding to the accelerator openings A1 and A2. Here, since the accelerator openings A1 and A2 are corrected based on the accelerator-off threshold Aref1 when the stop holding control is started, it is determined whether or not the accelerator openings A1 and A2 are both larger than the accelerator-on threshold Aref2. The determination is based on the calibrated accelerator opening degrees A1 and A2, and is more appropriate than that in which the accelerator opening degrees A1 and A2 are not corrected by the accelerator-off threshold Aref1. Thereby, cancellation | release of stop holding control can be performed more appropriately.

  Next, drive control immediately after canceling such stop holding control will be described. FIG. 5 is a flowchart showing an example of a drive control routine executed by the vehicle control electronic control unit 70. This routine is executed every predetermined time (for example, every several msec). When the drive control routine is executed, the CPU 72 of the vehicle control electronic control unit 70 first inputs the accelerator opening A1 from the accelerator sensor 84a that is the main accelerator sensor (step S300), and enters the stop holding execution flag Fstop. It is determined whether or not a predetermined time (for example, several seconds) has elapsed since the value 0 was set (step S310). When a predetermined time has elapsed since the value 0 is set in the stop holding execution flag Fstop, the normal driving force map is selected as the execution map (step S320), and the value 0 is set in the stop holding execution flag Fstop. When the predetermined time has not elapsed, the driving force map at the time of stopping holding control release set as a relationship in which the driving force with respect to the accelerator opening A1 is smaller than the normal driving force map is selected as an execution map (step S330). Based on the opening degree A1 and the selected execution map, the required driving force Td * is set (step S340), the set required driving force Td * is transmitted to the engine ECU 23 (step S350), and this routine is terminated. . FIG. 6 shows an example of a normal driving force map and a stop holding control canceling driving force map. As shown in the figure, the driving force map at the time of stopping holding control cancellation is set to be smaller, especially on the low accelerator opening side, so that the driving force with respect to the accelerator opening A1 is set smaller than the normal driving force map. It has become. By setting the required driving force Td * using the driving force map at the time of stopping holding control release set in this way, the vehicle starts with a large driving force unexpected by the driver when the stopping holding control is released. Can be suppressed. As a result, the behavior of the vehicle immediately after canceling the stop holding control can be stabilized. The engine ECU 23 that has received the required driving force Td * controls the operation of the engine 22 so that the required driving force Td * is output to the front wheels 34a and 34b.

  Next, the zero point learning of the accelerator openings A1 and A2 will be described. FIG. 7 is a flowchart showing an example of a zero point learning control routine executed by the vehicle control electronic control unit 70. When the zero point learning control routine is executed, the CPU 72 of the vehicle control electronic control unit 70 first inputs data necessary for zero point learning, such as the accelerator opening degrees A1 and A2 and the zero point learning flag Fa (step S400). ), Whether or not the zero point learning flag Fa is 0 (step S410) and whether any of the accelerator opening degrees A1 and A2 is less than 0 (step S420). Since the zero point learning is prohibited when the zero point learning flag Fa is 1, the routine is terminated without learning. If neither the accelerator opening A1 nor A2 is greater than or equal to 0, it is not necessary to learn the zero point, so this routine is terminated. When the zero point learning flag Fa is 0 and either of the accelerator openings A1 and A2 is less than 0, both the accelerator openings A1 and A2 are corrected to 0 (step S430), and this routine is terminated. To do. Thereby, even if the sensor values of the two accelerator sensors 84a and 84b change due to secular change, the zero points of the accelerator openings A1 and A2 can be made appropriate.

  According to the vehicle 20 of the embodiment described above, since the stop holding control is started on the condition that one of the accelerator opening degrees A1 and A2 has reached less than the accelerator off threshold Aref1, the stop holding control is further performed. You can start more quickly and properly. In addition, according to the automobile 20 of the embodiment, since the stop holding control is canceled on the condition that both of the accelerator openings A1 and A2 are larger than the accelerator on threshold Aref2, the stop holding control is more reliably performed. It can be released properly. Moreover, since the accelerator opening A1 and A2 are corrected and calibrated by the accelerator-off threshold Aref1 when the stop holding control is started, the subsequent stop holding control can be canceled more appropriately and the next stop holding control can be performed. Can be started more appropriately.

  In addition, according to the automobile 20 of the embodiment, the stopping power with respect to the accelerator opening A1 is set smaller than the normal driving power map until a predetermined time elapses after the stop holding control is canceled. Since the required driving force Td * is set using the driving force map at the time of holding control release, it is possible to suppress the vehicle from starting due to a large driving force unexpected by the driver when the stop holding control is released. As a result, the behavior of the vehicle immediately after canceling the stop holding control can be stabilized.

  Furthermore, according to the vehicle 20 of the embodiment, after the stop holding control is started, the zero point learning of the accelerator openings A1 and A2 is prohibited until the stop is released, so that the driver is performing the stop holding control. When the brake pedal 85 is lifted up, etc., and learning from the zero point that is negative than the normal zero point, the stop holding control release determination becomes inappropriate. It is possible to suppress the occurrence of an inappropriate determination of the start of the vehicle stop holding control.

  In the vehicle 20 of the embodiment, as a condition for starting the stop holding control, in addition to a condition in which either the accelerator opening A1 or A2 is less than the accelerator-off threshold Aref1, a condition in which the vehicle speed V is 0 or a brake on Although certain conditions are included, conditions other than these may be further included, or one of the conditions where the vehicle speed V is 0 and the brake-on condition may not be included.

  In the automobile 20 of the embodiment, as a condition for canceling the stop holding control, it is assumed that both the accelerator opening A1 and A2 include a condition in which the accelerator opening threshold Aref2 is greater than either of the accelerator opening A1 and A2. The stop holding control may be canceled under the condition that becomes greater than the accelerator-on threshold Aref2.

  In the automobile 20 of the embodiment, when the stop holding control is started, the accelerator openings A1 and A2 are corrected based on the accelerator-off threshold Aref1, but the accelerator openings A1 and A2 are not corrected. It doesn't matter.

  In the automobile 20 of the embodiment, the zero opening learning of the accelerator openings A1 and A2 is prohibited while the stop holding control is being executed, but the accelerator opening A1 is being executed even while the stop holding control is being executed. , A2 zero point learning may be performed. Moreover, it does not matter that the zero point learning of the accelerator opening A1, A2 is not performed.

  In the automobile 20 of the embodiment, when the stop holding control is released, the driving force with respect to the accelerator opening A1 is set smaller than the normal driving force map until a predetermined time elapses after the stop holding control is released. Although the required driving force Td * is set using the driving force map, the required driving force Td * may be set using the normal driving force map immediately after the stop holding control is canceled.

  In the automobile 20 of the embodiment, the stop holding control is started or the control is released when the brake hold switch 89 is turned on. However, the stop holding control is performed regardless of whether the brake hold switch 89 is turned on or off. It can be started or the control can be released.

  The automobile 20 of the embodiment has been described as a front-wheel-drive automobile in which the power from the engine 22 is shifted by the automatic transmission 24 and output to the front wheels 34a and 34b, but the brake wheel cylinders 36a to 36d of the left and right front and rear wheels 34a to 34d are described. As long as the cylinder pressure can be maintained, the present invention may be applied to a rear-wheel drive vehicle. Moreover, it is good also as what applies to the hybrid vehicle which mounts not only the motor vehicle which drive | works with the motive power from such an engine 22 but the motor and the motor which drive | works with the motive power from a motor.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the automobile manufacturing industry.

It is a block diagram which shows the outline of a structure of the motor vehicle 20 as one Example of this invention. 3 is a configuration diagram illustrating an example of a configuration of a brake actuator 40. FIG. 4 is a flowchart showing an example of a stop holding start control routine executed by a vehicle control electronic control unit 70. 4 is a flowchart showing an example of a stop holding release control routine executed by a vehicle control electronic control unit 70. 5 is a flowchart showing an example of a drive control routine executed by the vehicle control electronic control unit 70. It is explanatory drawing which shows an example of the driving force map at the time of normal time, and the driving force map at the time of stop holding | maintenance control cancellation | release. 7 is a flowchart showing an example of a zero point learning control routine executed by the vehicle control electronic control unit 70.

Explanation of symbols

20 automobiles, 22 engines, 23 electronic control units (engine ECU) for engines, 24 automatic transmissions, 25 electronic control units for automatic transmissions (ATECU), 32 differential gears, 34a-34d left and right front and rear wheels, 36a-36d brake wheel cylinders, 40 Brake actuator, 41 Brake actuator for front wheel, 42, 52 Supply oil path, 43a, 43b, 53a, 53b Pressure-reducing oil path, 44a, 44b, 54a, 54b Holding solenoid valve, 45, 55 Pressure-reducing oil path, 46a, 46b , 56a, 56b Pressure reducing solenoid valve, 47, 57 Reservoir, 48, 58 Oil pump, 49a, 49b, 59a, 59b Backflow prevention valve, 51 Rear wheel brake actuator, 60 Electronic control unit for brake (brake ECU), 70 Vehicle control electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84a, 84b accelerator sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89 brake hold switch, 90 brake master cylinder, 92 pressure sensor.

Claims (10)

Braking force applying means for applying a braking force to the vehicle based on the driver's braking operation and capable of applying the braking force to the vehicle regardless of the driver's braking operation;
Two different accelerator operation amount detecting means for detecting the driver's accelerator operation amount,
When a predetermined start condition including a condition that the accelerator operation amount detected by one of the two accelerator operation amount detection means is less than the accelerator-off threshold is satisfied while the vehicle is stopped, the driver's A stop holding control is performed to control the braking force applying means so that the braking force is applied and the stop state is maintained regardless of the brake operation, and the two accelerators are executed during the stop holding control. The braking force so that the stop holding control is released when a predetermined release condition is satisfied, including a condition that an accelerator operation amount detected by at least one of the operation amount detection means is equal to or greater than an accelerator-on threshold. Stop holding control means for controlling the giving means;
Automobile equipped with. The automobile according to claim 1,
Vehicle speed detection means for detecting the vehicle speed,
The predetermined start condition is a condition including a condition for detecting a vehicle speed of value 0 by the vehicle speed detecting means. The automobile according to claim 1 or 2,
Brake operation amount detection means for detecting the brake operation amount of the driver is provided,
The predetermined start condition is a condition that includes one condition that a brake operation amount detected by the brake operation detection means is less than a brake-off threshold.   4. The predetermined release condition is a condition including one condition in which both of the accelerator operation amounts detected by both of the two accelerator operation detecting means are equal to or greater than an accelerator on threshold value. Car.   Detected by the two accelerator operation detecting means when the predetermined start condition is satisfied when the accelerator operation amount detected by one of the two accelerator operation detecting means is less than the accelerator off threshold. The automobile according to any one of claims 1 to 4, further comprising accelerator operation amount correction means for correcting each accelerator operation amount based on an accelerator off threshold. The automobile according to any one of claims 1 to 5,
Learning means for learning the accelerator operation amount value 0 based on the respective accelerator operation amounts detected by the two accelerator operation amount detection means;
Learning prohibiting means for prohibiting learning by the learning means when the stop holding control is executed by the stop holding control means when the predetermined start condition is satisfied;
Automobile equipped with. The automobile according to any one of claims 1 to 6,
Driving force means capable of outputting driving force for traveling;
If the stop holding control is not canceled until the stop holding control is canceled by the stop holding control means until the predetermined stop condition is satisfied, the accelerator operation amount detected by one of the two accelerator operation amount detection means The required driving force required for the vehicle is set with the first relationship, and when the stop holding control is released, the first operation amount is detected with respect to the accelerator operation amount detected by one of the two accelerator operation amount detection means. Required driving force setting means for setting the required driving force with a second relationship in which the required driving force tends to be smaller than the relationship of
Drive control means for controlling the drive force means so that a drive force based on the set required drive force is output;
Automobile equipped with.   8. The automobile according to claim 7, wherein the second relationship is a relationship in which a required driving force is set to be smaller than the first relationship in a range where the detected accelerator operation amount is small. The automobile according to any one of claims 1 to 8,
Control execution instruction means for instructing execution of the stop holding control based on a driver's operation,
The stop holding control means is means for executing the stop holding control when the predetermined start condition is satisfied in a state in which the stop execution control is instructed by the control execution instruction means. Two different accelerators for detecting the driver's accelerator operation amount and braking force applying means for applying a braking force to the vehicle based on the driver's brake operation and applying the braking force to the vehicle regardless of the driver's brake operation A control method for an automobile comprising an operation amount detection means,
When a predetermined start condition including a condition that the accelerator operation amount detected by one of the two accelerator operation amount detection means is less than the accelerator-off threshold is satisfied while the vehicle is stopped, the driver's A stop holding control is performed to control the braking force applying means so that the braking force is applied and the stop state is maintained regardless of the brake operation, and the two accelerators are executed during the stop holding control. The braking force so that the stop holding control is released when a predetermined release condition is satisfied, including a condition that an accelerator operation amount detected by at least one of the operation amount detection means is equal to or greater than an accelerator-on threshold. A method for controlling an automobile characterized by controlling the applying means.

Images