JP2013104296A - Output control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an output control device which suppresses snatch when start acceleration from a partially-loaded state, and to improve drivability.SOLUTION: The output control device controls output of vehicle traveling power source based on the operation amount of an accelerator operation portion to which a driver inputs an acceleration operation. The output control device is configured to perform torque-down control for delaying a torque increase of the traveling power source, when the operation speed of the accelerator operation portion and the estimation torque change rate of the traveling power source are not lower than specific thresholds, respectively, and a load of the last traveling power source is not higher than a specific threshold.

Description

  The present invention relates to an output control device that controls the output of a driving power source such as an engine of a vehicle, and more particularly to a snatch for starting acceleration from a partial load state (a load state in which the output is lower than a full load (maximum output)). It is related to the thing which improved drivability while suppressing it.

For example, in a car equipped with a gasoline engine or the like, if the engine torque is suddenly raised when the accelerator pedal is depressed by the driver, the torsional vibration of the drive system (especially the drive shaft) is excited, which is referred to as a snatch on the vehicle body. May cause longitudinal vibration.
Conventionally, in order to suppress such a snatch, the engine torque is increased by throttle control that slowly opens and closes the throttle valve of the engine and ignition control that retards the ignition timing of the engine with respect to the operation of the accelerator pedal. It is known to delay.

As a conventional technique related to such vibration reduction at the start of acceleration, for example, Patent Document 1 discloses an acceleration state in which the backlash of the vehicle drive system is clogged based on the intake pipe negative pressure of the engine, or the backlash is opened. It is described that a predetermined torque increase delay control is performed when it is determined that the backlash is open.
According to this, it is possible to prevent a shock from occurring at the time of reacceleration after the accelerator is off.
Patent Document 2 describes that in engine torque control, considering the accelerator pedal depression speed, torque control is performed such that the longitudinal acceleration of the vehicle increases when the depression speed is high.
Japanese Patent Application Laid-Open No. 2004-228561 describes that the longitudinal vibration of the vehicle is suppressed by using the reverse phase torque of the engine obtained by ignition control when the accelerator pedal depression amount and depression speed are large.

JP 2010-174729 A JP-A-2005-155212 JP 2007-321742 A

  In order to prevent snatching, when performing torque down control that delays the increase in torque relative to pedal operation, if the accelerator pedal is further depressed from a partial load state where the accelerator pedal is depressed to some extent, simply If the increase in torque is delayed, a phenomenon called so-called hesitation occurs in which the vehicle does not accelerate against the driver's intention, and drivability (ease of driving) is impaired. There is also a concern that malfunctions may occur due to changes in the engine speed during acceleration or slight accelerator pedal movement.

On the other hand, if no torque-down control is performed from the accelerator-on state, a snatch may occur depending on the driving state, which reduces the comfort and texture of the vehicle.
The subject of this invention is providing the output control apparatus which improved the drivability while suppressing the snatch at the time of starting acceleration from a partial load state.

The present invention solves the above-described problems by the following means.
The invention according to claim 1 is an output control device that controls an output of a driving power source for a vehicle based on an operation amount of an accelerator operation unit to which a driver inputs an accelerator operation, wherein the accelerator operation unit is operated for a predetermined time. When the operation amount increases, at least one of the operation speed of the accelerator operation unit and the estimated torque change rate of the travel power source is equal to or greater than a predetermined threshold and the travel power just before The output control device is characterized in that torque down control for delaying the torque increase of the traveling power source is executed only when the load of the source is equal to or less than a predetermined threshold.
A snatch occurs only when a sudden accelerator operation is performed, and a snatch hardly occurs when the accelerator operation is performed slowly. Therefore, in the present invention, the torque-down control is performed only when at least one of the operation speed of the accelerator operation unit and the estimated torque change rate of the driving power source is equal to or greater than a predetermined threshold.
Further, when the vehicle is in an acceleration state, the backlash of the drive system is clogged, so that even if a sudden torque change occurs from there, a snatch is unlikely to occur. Therefore, in the present invention, the torque-down control is performed only when the load of the immediately preceding power source for traveling is not more than a predetermined threshold value.
As described above, according to the present invention, the torque down control is performed only when the inevitable conditions for the snatch countermeasures are met, so that the drivability is impaired by intervening the control even in the situation where the torque down control is not necessary. Or malfunction can be prevented.
Further, in a state where there is a concern about the occurrence of snatch, torque down control can be reliably executed to prevent snatch.

The invention according to claim 2 is characterized in that the torque-down control is executed only when the operating speed of the accelerator operating unit and the estimated torque change rate of the driving power source are both equal to or greater than a predetermined threshold. The output control device according to claim 1.
According to this, it is possible to perform appropriate torque down control with higher control accuracy.

According to a third aspect of the present invention, the travel power source is an engine whose output is adjusted by a throttle valve, and a load of the travel power source is determined based on an opening of the throttle valve. An output control apparatus according to claim 1 or claim 2.
According to this, it is possible to perform appropriate control with high accuracy and little time response delay in an engine that adjusts the output by the throttle valve.

  As described above, according to the present invention, it is possible to provide an output control device that suppresses a snatch when acceleration is started from a partial load state and improves drivability.

It is a block diagram which shows the structure of the Example of the output control apparatus to which this invention is applied. It is a flowchart which shows operation | movement of the output control apparatus of FIG. FIG. 2 is a diagram schematically showing an example of changes in accelerator opening, accelerator opening speed, estimated torque change rate, and immediately preceding throttle opening in a vehicle having the output control device of FIG. 1. It is a figure which shows typically the other example of transition of an accelerator opening degree, an accelerator opening speed, an estimated torque change rate, and the last throttle opening in the vehicle which has the output control apparatus of FIG. It is a figure which shows typically the other example of transition of an accelerator opening degree, an accelerator opening speed, an estimated torque change rate, and the last throttle opening in the vehicle which has the output control apparatus of FIG.

  An object of the present invention is to provide an output control device that suppresses snatching when acceleration is started from a partial load state and improves drivability. An accelerator pedal opening speed is predetermined when the accelerator is stepped on from accelerator-on. The problem is solved by executing the torque-down control only when the value is equal to or greater than the value, the previous throttle opening is equal to or smaller than the predetermined value, and the rate of change of the estimated torque is equal to or greater than the predetermined value.

Embodiments of an output control apparatus to which the present invention is applied will be described below.
The output control device according to the embodiment is mounted on an automobile such as a passenger car using a gasoline engine whose output is adjusted by a throttle valve such as a butterfly valve as a driving power source.
FIG. 1 is a block diagram illustrating the configuration of the output control apparatus according to the embodiment.
The output control device 1 includes an engine control unit 10, an accelerator pedal sensor 20, a throttle actuator 30, a throttle sensor 40, and the like.

The engine control unit 10 comprehensively controls the engine and its auxiliary equipment.
The engine control unit 10 includes an information processing device such as a CPU, a storage device such as a RAM and a ROM, an input / output interface, and a bus connecting them.

  The accelerator pedal sensor 20 is provided in an accelerator pedal to which a driver inputs an accelerator operation (acceleration request operation), detects an operation amount (depression amount) of the accelerator pedal by a position encoder, and transmits it to the engine control unit 10. .

  The throttle actuator 30 opens and closes the throttle valve of the engine in response to a command from the engine control unit 10.

  The throttle sensor 40 detects the opening (angular position) of the throttle valve with a position encoder and transmits it to the engine control unit 10.

The engine control unit 10 calculates a driver request torque based on an input from the accelerator pedal sensor 20.
The engine control unit 10 sets a target opening of the throttle valve in accordance with the driver request torque, and controls the drive of the throttle actuator 30 while feeding back the input from the throttle sensor 40.
The engine control unit 10 also has a function of calculating the estimated torque of the engine based on various parameters such as the throttle valve opening, ignition timing, fuel injection amount, intake pipe negative pressure, and supercharging pressure.

Further, the engine control unit 10 increases the engine torque by delaying the opening of the throttle valve and delaying the ignition timing with respect to the operation of the accelerator pedal when a predetermined condition is satisfied to suppress the snatch. Torque down control is performed to delay.
FIG. 2 is a flowchart showing the operation of the engine control unit related to torque down control.
Hereinafter, the steps will be described step by step.

<Step S01: Determination of accelerator off>
Based on the output of the accelerator pedal sensor 20, the engine control unit 10 determines whether or not the driver is in an accelerator-off state where the driver has not substantially depressed the accelerator pedal.
When it is in the accelerator off state, the process proceeds to step S02, and when it is in the accelerator on state where the accelerator pedal is depressed, the process proceeds to step S05.

<Step S02: Determination of accelerator on>
Based on the output of the accelerator pedal sensor 20, the engine control unit 10 determines whether the accelerator pedal has been depressed (accelerator-on state) after the accelerator-off state determined in step S01.
If the accelerator is on, the process proceeds to step S03. If the accelerator is off, the series of processes is terminated (returned).

<Step S03: Torque change rate determination>
The engine control unit 10 calculates the rate of change of the estimated torque of the engine accompanying the accelerator operation, and compares the calculated value with a predetermined threshold value set in advance.
If the estimated torque change rate is equal to or greater than the threshold value, the process proceeds to step S04. If the estimated torque change rate is less than the threshold value, the series of processing ends (returns).

<Step S04: Torque down control execution>
The engine control unit 10 performs torque-down control including throttle valve delay control by the throttle actuator 30 and ignition timing retard control so that the actual increase in engine torque is delayed with respect to the depression of the accelerator pedal. Run.
Thereafter, the series of processing is terminated (returned).

<Step S05: Acceleration time determination>
Based on the output of the accelerator pedal sensor 20, the engine control unit 10 determines whether or not the accelerator-on state continues for a predetermined time or more.
If the accelerator-on state continues for a predetermined time or longer, the process proceeds to step S06. If the predetermined time is not reached, the process returns to step S01 and the subsequent processing is repeated.

<Step S06: Judgment on Increase in Accelerator>
Based on the output of the accelerator pedal sensor 20, the engine control unit 10 determines whether or not the driver has stepped on the accelerator pedal (increase in the amount of depression).
If the accelerator is further depressed, the process proceeds to step S07. If not, the series of processes is terminated (returned).

<Step S07: Determination of accelerator opening speed>
The engine control unit 10 calculates the accelerator pedal depression speed (accelerator opening speed) by the driver based on the output history of the accelerator pedal sensor 20.
When the accelerator opening speed is equal to or higher than the predetermined threshold value, the process proceeds to step S08, and when the accelerator opening speed is lower than the threshold value, the series of processes is ended (returned).

<Step S08: Immediately before throttle opening determination>
Based on the output of the throttle sensor 40, the engine control unit 10 detects the throttle valve opening of the engine at the time immediately before the depression of the accelerator pedal is detected in step S06.
If the immediately preceding throttle valve opening is equal to or smaller than the predetermined threshold value, the process proceeds to step S09 assuming that the engine load is equal to or lower than the predetermined value, and if it exceeds the threshold value, the engine load is equal to the predetermined value. A series of processing is terminated (returned) because it is in a high load state exceeding the value.

<Step S09: Torque change rate determination>
The engine control unit 10 calculates the rate of change of the estimated torque of the engine accompanying the accelerator operation, and compares the calculated value with a predetermined threshold value set in advance.
If the estimated torque change rate is equal to or greater than the threshold value, the process proceeds to step S10. If the estimated torque change rate is less than the threshold value, the series of processing ends (returns).

<Step S10: Torque down control execution>
The engine control unit 10 performs torque-down control including throttle valve delay control by the throttle actuator 30 and ignition timing retard control so that the actual increase in engine torque is delayed with respect to the depression of the accelerator pedal. Run.
Thereafter, the series of processing is terminated (returned).

Hereinafter, an example of changes in the accelerator opening, the accelerator opening speed, the estimated torque change rate, and the immediately preceding throttle opening in a vehicle equipped with the output control apparatus of the embodiment will be described.
3 to 5 are graphs showing examples of these time histories.
In the example shown in FIG. 3, the accelerator pedal is depressed from the state in which the previous throttle opening is less than the threshold, and the accelerator opening speed is equal to or greater than the threshold. At this time, the estimated torque change rate of the engine is also equal to or greater than the threshold value, and as a result, torque down control is executed.
In this way, when the accelerator pedal is depressed suddenly from a state where the accelerator opening just before is small, a snatch is likely to occur unless the torque down control is executed. You can see that prevention is taking place.

On the other hand, in the example shown in FIG. 4, the accelerator pedal is suddenly increased similarly to FIG. 3, but the throttle opening just before the increase is greater than the threshold value. As a result, torque down control is performed. Is not running.
As described above, when the throttle is further increased from a state where the throttle opening is large, the drive system backlash is clogged and it is difficult for shocks to occur, so even if the torque down control is not performed, a snatch is generated. In addition, the torque reduction control causes a hesitation phenomenon that the vehicle does not accelerate as intended by the driver.
According to the present embodiment, such hesitation can be prevented, and the vehicle can be immediately accelerated to improve drivability.

In the example shown in FIG. 5, the previous throttle opening is equal to or less than the threshold value as in FIG. 3, but as a result of the driver depressing the accelerator pedal relatively slowly, the accelerator opening speed and the estimated torque change rate are respectively the threshold values. The torque down control is not executed.
In this way, snatching is unlikely to occur even when the accelerator pedal is slowly depressed, but when torque down control is performed for such slow accelerator operation, the above-mentioned hesitation or subtle accelerator A malfunction caused by erroneously detecting that the change in the pedal position is increased is a problem.
According to the present embodiment, such hesitation can be prevented and malfunction can also be reduced.

As described above, according to this embodiment, the torque down control is performed only when the accelerator pedal operation speed and the engine torque change rate are each equal to or higher than the predetermined threshold value and the immediately preceding throttle opening is equal to or lower than the predetermined threshold value. By executing, torque down control can be performed only when inevitable conditions for snatch countermeasures are met, and drivability is impaired by intervening control even in situations where torque down control is not necessary, It is possible to prevent malfunction.
Further, the accuracy of the control can be improved by grasping the state of the engine load change in combination with the depression speed of the accelerator pedal and the change in the estimated torque.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) The configuration of the output control device is not limited to that of the above-described embodiment, and can be changed as appropriate. The vehicle to be applied is not limited to a four-wheeled passenger vehicle, and other types of vehicles. It may be.
For example, the present invention can be applied to a two-wheeled vehicle that performs an accelerator operation by turning a grip provided on a handle about an axis, an ATV, or a welfare vehicle that performs an accelerator operation by means other than an accelerator pedal. it can.
(2) In the embodiment, the driving power source is, for example, a gasoline engine, and torque down control is performed by, for example, throttle control or ignition timing control. It is not limited to.
For example, in the case of a diesel engine, torque reduction control can be performed by controlling the fuel injection amount and injection timing.
The traveling power source may be an electric motor or an engine-electric hybrid system in which the electric motor is combined with an engine. In this case, the torque down control may be performed by any method as long as it can delay the increase in torque of the entire system.
(3) In the embodiment, the torque down control is executed when both the accelerator opening speed and the estimated torque change rate are equal to or greater than the threshold value. Such a configuration is preferable from the viewpoint of control accuracy. However, when priority is given to simplification of the control and the device, at least one of the accelerator operation speed and the estimated torque change rate is detected, and this is equal to or greater than a threshold value. Torque down control may be performed.
(4) In the embodiment, the throttle opening is used as a parameter for determining the engine load immediately before the accelerator operation, but the load of the driving power source may be determined using other parameters.
For example, the engine load may be determined based on the estimated torque of the engine or the accelerator operation amount.
In the case of a motor-driven vehicle, the load may be determined based on the power supplied to the motor.

1 Output Control Device 10 Engine Control Unit 20 Accelerator Pedal Sensor 30 Throttle Actuator 40 Throttle Sensor

Claims (3)

An output control device that controls an output of a driving power source for a vehicle based on an operation amount of an accelerator operation unit to which a driver inputs an accelerator operation,
When the operation amount increases after the accelerator operation unit has been operated for a predetermined time, at least one of the operation speed of the accelerator operation unit and the estimated torque change rate of the driving power source is equal to or greater than a predetermined threshold. An output control device that executes torque-down control that delays the increase in torque of the travel power source only when the load of the travel power source immediately before is less than or equal to a predetermined threshold value. 2. The torque down control is executed only when an operation speed of the accelerator operation unit and an estimated torque change rate of the driving power source are both equal to or greater than a predetermined threshold value. Output control device. The driving power source is an engine that adjusts output by a throttle valve,
The output control device according to claim 1 or 2, wherein a load of the traveling power source is determined based on an opening of the throttle valve.

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