JP2014152741A - Control device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a vehicle, which suppresses slowness in engine restarting from idling stop.SOLUTION: During execution of brake hold control, at least one of a predetermined opening degree Aand a predetermined time Tin an engine start condition from idling stop is small as compared with that during non-execution of the brake hold control. Therefore, during execution of the brake hold control, engine starting and, accordingly, vehicle starting can be performed quickly in response to accelerator operation. On the other hand, during non-execution of the brake hold control, engine starting unintended by a driver can be inhibited. Namely, it is possible to provide a control device 26 or the like of a vehicle 10, which suppresses slowness in engine restarting from idling stop.

Description

  The present invention relates to a vehicle control device, and more particularly, to an improvement for suppressing slack at the time of engine restart from an idling stop.

  The brake operation is released based on an automatic stop control for automatically stopping the engine based on a predetermined engine stop condition, an automatic start control for restarting the engine based on a predetermined engine start condition, and a predetermined brake hold condition. However, there is known a vehicle control device that executes brake hold control for maintaining braking force. For example, this is the control device for an idle stop vehicle described in Patent Document 1.

JP 2012-172737 A

  As the engine start condition from the idling stop, it can be considered that the accelerator opening is equal to or greater than a predetermined opening, the accelerator operation time is equal to or longer than a predetermined time, and the like. During execution of the brake hold control, it is conceivable that the driver's foot is away from the brake pedal, and the engine is started and the vehicle is started just by depressing the accelerator pedal. However, in the prior art, when the brake hold control is performed when the engine is restarted from the idling stop, even if the accelerator pedal is depressed, the engine is started until the engine start condition is satisfied. There was a problem that the driver felt sluggish because the start was not performed. Such a problem has been newly found in the process in which the present inventors have continued intensive research with the intention of improving the performance of a vehicle.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a vehicle control device that suppresses slack at the time of engine restart from an idling stop.

  In order to achieve such an object, the gist of the present invention is that an automatic stop control for automatically stopping an engine based on a predetermined engine stop condition, an accelerator opening being equal to or greater than a predetermined opening, and an accelerator Even if the brake operation is released based on an automatic start control for restarting the engine based on a predetermined engine start condition including at least one of the operation time being at least a predetermined time and a predetermined brake hold condition A vehicle control device that executes brake hold control for maintaining braking force, and at the time of execution of the brake hold control, at least one of the predetermined opening and the predetermined time in the engine start condition is the brake It is characterized in that it is smaller than when the hold control is not executed.

  According to this configuration, when the brake hold control is executed, at least one of the predetermined opening and the predetermined time in the engine start condition is smaller than that when the brake hold control is not executed. When the control is executed, the engine can be started and the vehicle can be started quickly according to the accelerator operation. On the other hand, when the brake hold control is not executed, the engine start not intended by the driver can be suppressed. That is, it is possible to provide a vehicle control device that suppresses the slack at the time of engine restart from the idling stop.

It is a figure which shows an example of the drive system and control system of the vehicle to which this invention is applied suitably. It is a functional block diagram which shows the principal part of the control function with which the control apparatus in the vehicle of FIG. 1 was equipped. 2 is a flowchart for explaining a main part of an example of engine automatic stop / automatic start control by the control device in the vehicle of FIG. 1.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating an example of a drive system and a control system of a vehicle 10 to which the present invention is preferably applied. As shown in FIG. 1, the vehicle 10 of this embodiment includes an engine 12 that is a drive source, a pair of front wheels 14 that are drive wheels, a pair of rear wheels 16, the engine 12 and the front wheels 14. And a transmission 18 provided in the power transmission path between the two. That is, the vehicle 10 is preferably an FF (front engine front wheel drive) type vehicle.

  The engine 12 is, for example, an internal combustion engine such as a direct injection gasoline engine or a diesel engine in which fuel is directly injected into a combustion chamber. The engine 12 is provided with various devices for controlling driving (output torque) of the engine 12. For example, as shown in FIG. 2, a throttle actuator 20 that controls opening and closing of an electronic throttle valve provided in the engine 12, a fuel injection device 22 that performs fuel injection control, an ignition device 24 that performs ignition timing control, and the like are provided. ing.

  The transmission 18 is, for example, a stepped automatic transmission mechanism in which any one of a plurality of predetermined shift speeds (transmission ratios) is selectively established. It is configured with joint elements. For example, a plurality of hydraulic friction engagement devices controlled by hydraulic actuators such as multi-plate clutches and brakes are provided, and the plurality of hydraulic friction devices according to the hydraulic pressure supplied from a hydraulic control circuit (not shown). By selectively engaging or releasing the engagement device, a plurality of (for example, first to sixth speeds) forward shift stages (forward gears) according to the combination of the coupling states of the hydraulic friction engagement devices. Stage, forward travel gear stage) or reverse shift stage (reverse gear stage, reverse travel gear stage) is selectively established. The transmission 18 may be a well-known belt-type continuously variable transmission (CVT) or the like.

  The vehicle 10 includes a control system as illustrated in FIG. That is, an engine control device 26, an eco-run control device 28, a VSC 30 as a brake control device, an air conditioner control device 32, and an integrated control device 34 (hereinafter referred to as the control device 26 and the like unless otherwise distinguished) are provided. These control devices 26 and the like are each configured to include a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU stores in advance in the ROM while using a temporary storage function of the RAM. Signal processing according to the program. That is, in the vehicle 10, the control device 26 and the like are configured by being divided into a plurality of control devices (ECUs), and a vehicle control device that performs various controls by mutual communication of information will be described. The control device 26 or the like may be configured as a single control device. In the present embodiment, the engine control device 26, the eco-run control device 28, the VSC 30 and the like correspond to the control device of the vehicle 10.

Various input signals detected by sensors or switches provided in the vehicle 10 are supplied to the control device 26 and the like. For example, a signal indicating the accelerator opening degree A _CC detected by the accelerator opening sensor 38 corresponding to the depression operation of the accelerator pedal 36, and detected by the brake boost negative pressure sensor 42 corresponding to the depression operation of the brake pedal 40. A signal representing the brake boost negative pressure P _b , a signal representing the crank angle (position) A _CR of the engine 12 detected by the crank angle sensor 44, a signal representing the cam angle A _CA detected by the cam angle sensor 46, vehicle speed A signal representing the vehicle speed V corresponding to the output rotational speed N _OUT of the transmission 18 detected by the sensor 48, a signal representing the charged amount SOC of the battery 50 detected by the battery sensor 52, and turning on / off the eco-run cancel switch 54 Indicating the ON / OFF state of the hood lock switch 56, and the brake hold switch Signal or the like representing the 0 on and off is input to the controller 26 or the like.

  Various output signals are supplied to each device provided in the vehicle 10 from the control device 26 or the like. For example, signals supplied to the throttle actuator 20, the fuel injection device 22, and the ignition device 24 for driving the engine 12, and a tandem starter 58 and a tandem starter driving relay 60 for starting control of the engine 12. , A signal supplied to a motor or the like provided in the electric oil pump 62 for driving control of the electric oil pump 62, a signal for controlling the operation of the air conditioner 64, etc. 26 and the like are supplied to each device. The vehicle 10 includes a meter 66 in the vicinity of the driver's seat, and the vehicle speed V, on / off of the eco-run mode, and the like are displayed on the meter 66 by a signal supplied from the control device 26 or the like. When the engine 12 is driven, power is generated by the alternator 68 and the generated electric energy is stored in the battery 50. The tandem starter 58 performs cranking of the engine 12 using electrical energy stored in the battery 50 when the engine 12 is started.

The engine control device 26 controls driving of the engine 12. That is, in addition to controlling the opening and closing of the electronic throttle valve by the throttle actuator 20 for throttle control, the fuel injection by the fuel injection device 22 is controlled for fuel injection control, and the ignition device 24 for ignition timing control. The output control of the engine 12 is executed, for example, by controlling the ignition timing. At the time of starting the engine 12, the engine 12 is cranked by the tandem starter 58 using the electric energy stored in the battery 50. The engine speed _NE is increased by such cranking, and the engine ignition and fuel supply are started via the fuel injection device 22, the ignition device 24, etc., whereby the autonomous operation of the engine 12 is started.

  The eco-run control device 28 performs eco-run control in the vehicle 10. That is, when the vehicle 10 is stopped due to a signal waiting or traffic jam, control for automatically stopping the engine 12 is executed. When an operation indicating the vehicle start intention is performed by the driver, the engine 12 is restarted to control the vehicle 10 to start. Specifically, automatic stop control and automatic start control described later are executed via the engine control device 26. Preferably, in the state where the eco-run cancel switch 54 is turned on, such automatic stop control and automatic start control are not executed (not executed).

  The VSC 30 performs vehicle behavior control that stabilizes the posture of the vehicle 10 when turning. For example, such control is performed by controlling brake devices provided respectively on the front wheel 14 and the rear wheel 16. Specifically, when an unstable state of the vehicle 10 such as oversteer or understeer is detected from each wheel detected by a wheel speed sensor (not shown), that is, the rotational speed of the front wheel 14 and the rear wheel 16, By controlling the brake devices provided on the front wheels 14 and the rear wheels 16 respectively, the posture of the vehicle 10 is automatically controlled to suppress a sudden change in behavior.

  FIG. 2 is a functional block diagram showing the main part of the control function provided in the control device 26 and the like. The automatic stop control unit 80 shown in FIG. 2 performs automatic stop control (idling stop control) for automatically stopping the engine 12 based on a predetermined engine stop condition. For example, the automatic stop control is performed based on the engine stop condition that the vehicle 10 is stopped and the engine 12 is in an idling state. That is, preferably, when the vehicle speed V detected by the vehicle speed sensor 48 is zero and the engine 12 is in an idling state (idle operation state), it is determined that the engine stop condition is satisfied. Performs automatic stop control. Preferably, the engine stop condition is satisfied when the vehicle speed V detected by the vehicle speed sensor 48 is zero and the engine 12 is idling for a predetermined time or more. The automatic stop control is performed as a thing. Specifically, the fuel injection control by the fuel injection device 22 and the ignition control by the ignition device 24 are stopped via the engine control device 26.

When the automatic stop control for automatically stopping the engine 12 is performed by the automatic stop control unit 80, the crank angle _ACR at the time of stopping the engine 12 is preferably stored in a memory or the like. Preferably, the electric oil pump 62 is driven while the engine 12 is stopped, and a predetermined hydraulic pressure is generated from the electric oil pump 62. With this control, necessary and sufficient hydraulic pressure is supplied to the transmission 18 when the engine 12 is restarted. Preferably, even when the engine stop condition is satisfied, the automatic stop control unit 80 does not execute the automatic stop control (does not execute) when a predetermined engine stop prohibition condition is satisfied. ). For example, if the start of the left open the hood panel engine 12 is performed, when the brake boost negative pressure P _b detected by the brake boost negative pressure sensor 42 is less than a specified threshold value, or the battery sensor 52 The automatic stop control is not executed even when the engine stop condition is satisfied, for example, when the charged amount SOC of the battery 50 detected by the above is less than a predetermined threshold.

The automatic start control unit 82 performs automatic start control for restarting the engine 12 based on predetermined engine start conditions. That is, when the engine 12 is automatically stopped by the automatic stop control unit 80, if the engine start condition is satisfied, the engine 12 is automatically started (restart from idling stop). Control). The engine start condition is that (a) the accelerator opening degree A _CC detected by the accelerator opening degree sensor 38 is _{equal to} or greater than a predetermined opening degree A _bo , and (b) the operation time T of the accelerator pedal 36 is a predetermined time period. Including at least one of T _{bo and} higher. The operation time T of the accelerator pedal 36 means, for example, the time during which the accelerator opening degree A _CC detected by the accelerator opening degree sensor 38 is a value (positive value) larger than zero. However, in the configuration provided with a sensor that detects whether or not the accelerator operation is performed separately from the accelerator opening sensor 38, even if the state in which the accelerator operation is detected by the sensor (accelerator on state) continues. Good. In the automatic start control unit 82, preferably, the shift position is the travel position (D position), and the brake pedal 40 is not depressed (the driver's foot is released from the brake pedal 40). In the case where at least one of the conditions (a) and (b) is satisfied, the automatic start control is performed assuming that the engine start condition is satisfied. Specifically, it performs cranking of the engine 12 by the tandem starter 58 using electrical energy stored in the battery 50 via the engine controller 26, pulling the engine speed N _E to a predetermined value or more Then, autonomous operation of the engine 12 is started by starting engine ignition and fuel supply via the fuel injection device 22 and the ignition device 24.

The automatic start control unit 82, a preferably automatic starting control for restarting the engine 12 based on the crank angle A _CR stored in the memory or the like during the automatic stop of the engine 12 by the automatic stop control unit 80 Do. That is, based on the crank angle _ACR at the time of automatic stop of the engine 12 stored in the memory or the like, it is determined from which cylinder the fuel is injected and ignited when the engine 12 is restarted. Preferably, even if the engine start condition is satisfied, the automatic start control unit 82 does not execute the automatic start control (does not execute) when a predetermined engine start prohibition condition is satisfied. ). For example, when the shift position is a non-traveling position (N position or P position), the automatic start control is not executed even when the engine start condition is satisfied.

The brake hold control unit 84 performs brake hold control that maintains the brake force (braking force) even when the brake operation is released based on a predetermined brake hold condition. That is, even when the brake pedal 40 is not depressed and the driver's foot is released from the brake pedal 40, the brake device provided in the front wheel 14 and the rear wheel 16 via the VSC 30 or the like is used. Performs control to generate braking force. For example, when the brake hold switch 70 is on and the vehicle 10 is stopped by decelerating by depressing the brake pedal 40, the depressing operation of the brake pedal 40 is released ( Even after the driver's foot is released from the brake pedal 40, the brake device is controlled to generate a braking force. The brake hold control unit 84 releases the brake hold control based on a predetermined brake hold release condition. For example, when the depression operation of the accelerator pedal 36 is performed, the brake hold control is released assuming that the brake hold release condition is satisfied. Preferably, when the accelerator opening degree A _CC detected by the accelerator opening degree sensor 38 is equal to or greater than a prescribed threshold value, the brake hold control is released assuming that the brake hold release condition is satisfied. The threshold value of the accelerator opening degree A _CC related to the brake hold release condition is preferably smaller than the threshold value of the accelerator opening degree A _CC related to the engine start condition, that is, the predetermined opening degree A _bo .

Preferably, the automatic start control unit 82 makes the accelerator-on determination condition related to the engine start condition stricter when the brake hold control unit 84 executes the brake hold control than when it is not executed. In other words, the engine start condition is set (changed) so that the accelerator-on determination is performed in response to a lighter accelerator operation. That is, at the time of execution of the brake hold control by the brake hold control unit 84, at least one of the predetermined opening A _bo and the predetermined time T _{bo in} the engine start condition is compared to when the brake hold control is not executed. Small value. For example, when the brake hold control is executed, the predetermined opening A _bo in the engine start condition is 0.5% or more, the predetermined time T _bo is 0 (that is, immediately after the accelerator is turned on), and the like. When the brake hold control is not executed, the predetermined opening A _bo in the engine start condition is set to 5% or more, the predetermined time T _bo is set to 200 ms or more, and the like.

  FIG. 3 is a flowchart for explaining a main part of an example of the engine automatic stop / automatic start control by the control device 26 and the like, and is repeatedly executed at a predetermined cycle.

First, in step (hereinafter, step is omitted) S1, whether or not a mode for executing the automatic stop control and automatic start control (stop and start control; S & S) is established (eco mode 2 or 3). Whether or not) is determined. If the determination in S1 is negative, the routine is terminated accordingly. If the determination in S1 is affirmative, in S2, for example, the brake hold switch 70 is turned on. It is determined whether or not the mode for executing the hold control is established (whether the brake hold control is being executed or the brake hold control is in standby). If the determination in S2 is affirmative, in S3, the accelerator-on determination in the execution condition of the automatic start control, that is, the engine start condition is strictly set. For example, after the predetermined opening degree A _bo in the engine starting condition is set to 0.5% or more and the predetermined time T _bo is set to 0 or the like, this routine is ended. If the determination in S2 is negative, in S4, the accelerator start determination in the execution condition of the automatic start control, that is, the engine start condition is set to a normal value (a value higher than the set value in S3). For example, after the predetermined opening degree A _bo in the engine start condition is set to 5% or more and the predetermined time T _bo is set to 200 ms or more, the present routine is terminated. In the above control, S1 corresponds to the operation of the automatic stop control unit 80, S1, S3, and S4 correspond to the operation of the automatic start control unit 82, and S2 corresponds to the operation of the brake hold control unit 84, respectively.

Thus, according to this embodiment, at the time of execution of the brake hold control, at least one of the predetermined opening A _bo and the predetermined time T _{bo in} the engine start condition is at the time of non-execution of the brake hold control. Therefore, when the brake hold control is executed, the engine can be started quickly and the vehicle can be started in response to the accelerator operation. On the other hand, when the brake hold control is not executed, the engine start not intended by the driver is suppressed. it can. That is, it is possible to provide the control device 26 of the vehicle 10 and the like that suppresses slack at the time of engine restart from the idling stop.

  The preferred embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. Is.

  10: Vehicle, 12: Engine, 26: Engine control device, 28: Eco-run control device, 30: VSC

Claims (1)

Automatic stop control for automatically stopping the engine based on a predetermined engine stop condition;
Automatic start control for restarting the engine based on a predetermined engine start condition including at least one of an accelerator opening being a predetermined opening or more and an accelerator operation time being a predetermined time or more;
A vehicle control device that executes a brake hold control that maintains a braking force even when a brake operation is released based on a predetermined brake hold condition,
When the brake hold control is executed, at least one of the predetermined opening and the predetermined time in the engine start condition is smaller than when the brake hold control is not executed.

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