JP6257315B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a control device for an idle stop vehicle.

  It is known to perform an idle stop that stops the idle rotation of the internal combustion engine while the vehicle is stopped due to a signal or the like (for example, refer to the following patent document). In the existing idling stop system, when the vehicle speed is below a predetermined value, the brake pedal is depressed above a threshold value, and the conditions such as the cooling water temperature of the internal combustion engine and the voltage of the vehicle battery are sufficiently high, the internal combustion engine Stop the engine. During the idling stop, when there is a restart request such as when the driver removes his foot from the brake pedal or depresses the accelerator pedal, the internal combustion engine is restarted.

JP 2012-137018 A

  One of the conditions for ending idle stop and restarting the internal combustion engine is the steering torque, steering amount (angle) or steering speed (change of steering amount per unit time) of the steering wheel (steering wheel operated for steering). In some cases, a state in which (quantity) is equal to or greater than a threshold value continues for a predetermined determination time. The fact that the driver operates the steering wheel suggests that there is an intention to start the vehicle in the near future, such as waiting for the right or left turn timing at the intersection. Therefore, when it is detected that the steering wheel is operated during the idle stop, the internal combustion engine is restarted to prepare for the vehicle to restart.

  However, in addition to the operation force by the driver's hand, vibrations of the vehicle body and reaction input from the road surface via the steering wheel are transmitted to the steering wheel. There is a concern that the internal combustion engine restarts against the driver's intention because they displace the steering wheel. Therefore, as described above, it is preferable to determine that the idle stop end condition is satisfied only when the state in which the steering wheel is operated continues for the determination time. The existence of this determination time also functions effectively to prevent improper sudden start or the like.

  By the way, recently, in order to further improve the fuel consumption performance of the vehicle, the vehicle speed condition, which is one of the idle stop conditions, has been raised, and the idle stop is started before the vehicle stops. Yes.

  When the driver operates the steering wheel in the process of the idling stop of the internal combustion engine while the vehicle is running and the vehicle decelerates to stop, it is required to restart the internal combustion engine as soon as possible. . The fact that the driver steers before the vehicle is completely stopped is because it is strongly expressed that the vehicle has an intention of accelerating the vehicle immediately, such as when a timing suitable for a right turn or a left turn has come.

  However, conventionally, the determination time for determining whether or not the steering wheel is steered (that is, whether or not the idle stop end condition is satisfied) is always constant (for example, 0. 0) regardless of whether the vehicle is coasting or stopped. 5 seconds). Therefore, the internal combustion engine is restarted after waiting for a predetermined determination time even for the steering before stopping, and the vehicle cannot be started as quickly as the driver desires. There was a desire to give a feeling of being late.

  The present invention has been made by paying attention to the above-mentioned problems for the first time. In an idle stop vehicle, it is intended to restart the internal combustion engine at a timing desired by the driver so that the vehicle can restart. The purpose is.

The present invention provides a vehicle control device that performs idle stop for stopping idle rotation of an internal combustion engine when an idle stop condition is satisfied, and restarts the internal combustion engine when an idle stop end condition is satisfied, One of the conditions for ending the idle stop is that the steering torque, steering amount, or steering speed of the steering wheel is maintained for a determination time, and the idle stop is stopped before the vehicle speed becomes zero. When started, the control device is configured to set the determination time when the vehicle speed is high at the time when the steering wheel is operated to be shorter than the determination time when the vehicle speed at the time is lower .

  According to the present invention, in an idle stop vehicle, the internal combustion engine can be restarted and the vehicle can be restarted at a timing desired by the driver.

The figure which shows schematic structure of the internal combustion engine in one Embodiment of this invention. The timing diagram which shows the content of the control which the control apparatus of the embodiment performs.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine for a vehicle in the present embodiment. The internal combustion engine in the present embodiment is a spark ignition type 4-stroke gasoline engine, and includes a plurality of cylinders 1 (one of which is shown in FIG. 1). In the vicinity of the intake port of each cylinder 1, an injector 11 for injecting fuel is provided. A spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives spark voltage generated by the ignition coil and causes spark discharge between the center electrode and the ground electrode. The ignition coil is integrally incorporated in a coil case together with an igniter that is a semiconductor switching element.

  The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. On the intake passage 3, an air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream.

  The exhaust passage 4 for discharging the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 from the exhaust port of each cylinder 1 to the outside. An exhaust manifold 42 and an exhaust purification three-way catalyst 41 are disposed on the exhaust passage 4.

  The ECU 0 as the control device of the present embodiment is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like.

  The input interface includes a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal b output from an engine rotation sensor that detects the rotation angle and engine speed of the crankshaft, and depression of an accelerator pedal. An accelerator opening degree signal c output from a sensor that detects the amount or the opening degree of the throttle valve 32 as an accelerator opening degree (so-called required load), detects whether the brake pedal is depressed, or detects the depression amount of the brake pedal. Brake switch or pedaling amount signal d output from the sensor, intake air temperature / intake pressure signal e output from a temperature / pressure sensor that detects intake air temperature and intake negative pressure in the intake passage 3 (especially the surge tank 33), Cooling water temperature signal f output from a water temperature sensor that detects the cooling water temperature indicating the temperature of the internal combustion engine, the vehicle is located An inclination angle (or acceleration) signal g output from an inclination angle sensor (or acceleration sensor) that detects the gradient of the road surface that is being driven, and steering that is input to a steering wheel (a steering wheel that a driver operates for steering) A steering amount signal h or the like output from a sensor for detecting torque, steering amount (angle) of the steering wheel or steering speed (change amount of steering amount per unit time) is input.

  From the output interface, an ignition signal i is output to the igniter 13 of the spark plug 12, a fuel injection signal j is output to the injector 11, an opening operation signal k is output to the throttle valve 32, and the like.

  The processor of the ECU 0 interprets and executes a program stored in the memory in advance, calculates operation parameters, and controls the operation of the internal combustion engine. The ECU 0 acquires various information a, b, c, d, e, f, g, and h necessary for operation control of the internal combustion engine via the input interface, knows the engine speed, and is filled in the cylinder 1. Estimate the intake volume. Based on the engine speed, the intake air amount, and the like, various operating parameters such as required fuel injection amount, fuel injection timing (including the number of times of fuel injection for one combustion), fuel injection pressure, and ignition timing are determined. The ECU 0 applies various control signals i, j, k corresponding to the operation parameters via the output interface.

  The ECU 0 inputs a control signal o to an electric motor (starter motor or motor generator, not shown) at the time of starting the internal combustion engine (a cold start or a return from an idling stop), Cranking is performed by rotating the crankshaft with an electric motor. Cranking ends when the internal combustion engine starts from the first explosion to a continuous explosion and the engine speed, that is, the rotation speed of the crankshaft, exceeds a judgment value determined according to the coolant temperature, etc. (assuming that the explosion has been completed) To do.

  The ECU 0 of the present embodiment performs an idle stop that stops the idle rotation of the internal combustion engine when the vehicle stops due to a signal waiting or the like.

  The ECU 0 starts executing an idle stop that stops the idle rotation of the internal combustion engine when the idle stop condition is satisfied. The ECU 0 has a vehicle speed of a predetermined value (for example, a value of 10 km / h to 13 km / h) or less, and the driver is stepping on the brake pedal or the brake pedal operation amount (may be a master cylinder pressure). There is a history that the cooling water temperature and the battery voltage are higher than the predetermined values, and the vehicle speed has increased to a predetermined value (for example, a value of 10 km / h to 13 km / h) or more after the most recent restart of the internal combustion engine. It is determined that the idle stop condition is satisfied when all the conditions such as “is” are all satisfied.

  Then, after the idle stop condition is satisfied, when the idle stop end condition is satisfied, the internal combustion engine that has been idle stopped is restarted. The ECU 0 determines whether the driver has released his or her foot from the brake pedal or the amount of operation of the brake pedal has fallen below a predetermined value, conversely, the brake pedal has been further depressed, the accelerator pedal has been depressed, For example, it is determined that the idle stop termination condition has been satisfied when one of the three minutes has elapsed, the state in which the steering wheel has been operated continues for the determination time, and the like. Here, the “state in which the steering wheel is being operated” refers to a state in which the steering torque, steering amount, or steering speed of the steering wheel obtained by referring to the sensor output signal h is greater than a threshold value. .

  Therefore, in the present embodiment, when the idle stop is started before the vehicle speed becomes 0, one of the idle stop end conditions is that “the state where the steering wheel is operated continues for the determination time”. The determination time for determining is changed according to the current vehicle speed.

  FIG. 2 illustrates the vehicle speed, the steering torque input to the steering wheel, and the transition of ON / OFF of the idle stop flag when the idle stop is started before the vehicle speed becomes zero. In FIG. 2, for the steering torque and idle stop flag, the broken line represents the case where the steering wheel is operated before the vehicle is completely stopped, and the solid line is the case where the steering wheel is operated after the vehicle is completely stopped Represents.

  T is a threshold value to be compared with the steering torque input to the steering wheel. α and β are determination times counted from the time point when the steering torque input to the steering wheel becomes equal to or greater than the threshold value T. α is a determination time in a case where the steering torque becomes equal to or greater than the threshold T before the vehicle completely stops, that is, a case represented by a broken line. β is a determination time in a case where the steering torque becomes equal to or greater than the threshold T after the vehicle is completely stopped, that is, a case represented by a broken line.

  The ECU 0 of this embodiment sets the determination times α and β according to the vehicle speed at the time when the steering wheel is operated after the start of the idle stop. The ECU 0 makes the determination time α when the vehicle speed at the time is relatively high shorter than the determination time β when the vehicle speed at the time is low. Specifically, the determination time α when the vehicle speed is not zero or higher than a predetermined value close to zero (not yet stopped) is set to 0.2 seconds. On the other hand, the determination time β when the vehicle speed is 0 or less than a predetermined value close to 0 or 0 (becomes stopped) is 0.5 seconds.

  If the steering torque becomes greater than or equal to the threshold T before the vehicle stops, if the state where the steering torque is greater than or equal to the threshold T continues for 0.2 seconds or more, the internal combustion engine is restarted as if the idle stop termination condition has been satisfied To do. On the other hand, if the steering torque becomes equal to or greater than the threshold T before the vehicle stops, the state where the steering torque is equal to or greater than the threshold T does not continue for 0.5 seconds or longer (other idle stop termination conditions are satisfied. Do not restart the internal combustion engine unless otherwise).

  In the present embodiment, the vehicle control device 0 performs idling stop for stopping idling rotation of the internal combustion engine when the idling stop condition is satisfied, and restarts the internal combustion engine when the idling stop end condition is satisfied. One of the conditions for ending the idle stop includes that the state where the steering torque, the steering amount or the steering speed of the steering wheel is equal to or higher than the threshold value continues for the determination time, and the idle speed is reached before the vehicle speed becomes zero. In the case where the stop is started, the control device is configured in which the determination time is variable according to the current vehicle speed.

  According to this embodiment, in the idle stop vehicle, the internal combustion engine can be restarted in accordance with the timing desired by the driver. That is, after the idling stop is started before the vehicle speed becomes zero, when the driver steers faster than the vehicle completely stops, the internal combustion engine is restarted as soon as possible, and the driver desires Such a rapid start can be realized.

  The present invention is not limited to the embodiment described in detail above. For example, in the above-described embodiment, the determination time is two steps of α and β. However, the determination time is adjusted in multiple steps so that the determination time is shortened as the vehicle speed at the time when the steering wheel is operated is high. It is good.

  Other specific configurations of each part can be variously modified without departing from the spirit of the present invention.

  The present invention can be applied to control of a vehicle equipped with an internal combustion engine.

0 ... Control device a ... Vehicle speed signal h ... Steering torque, steering amount or steering speed signal T ... Threshold values α, β ... Determination time

Claims (1)

A vehicle control device that performs idle stop for stopping idle rotation of the internal combustion engine when the idle stop condition is satisfied, and restarts the internal combustion engine when the idle stop end condition is satisfied,
One of the idle stop termination conditions includes that the steering torque, the steering amount, or the steering speed of the steering wheel continues for a determination time,
When the idling stop is started before the vehicle speed becomes 0, the determination time when the vehicle speed is high when the steering wheel is operated is set shorter than the determination time when the vehicle speed at the time is lower Control device.

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