JPH08218919A - Driving force control method - Google Patents

Abstract

PURPOSE: To achieve a target driving torque without detecting output rotating speed of a toque converter directly by calculating the product of the torque ratio and the gear ratio of the torque converter from a map according to the ratio between engine rotating speed and a car speed. CONSTITUTION: At first from car speed and an acceleration operating amount, a target driving shaft torque is calculated on reference to a there dimentional map 1. The map 1 is prepared with reference to the driving torque characteristics of an automobile. After the target driving shaft torque is calculated, the target driving shaft torque is divided by a final gear ratio, and then a target output shaft torque is calculated. On the other hand, engine speed is divided by car speed, a constant multiply by an obtained value, and then a rotary ratio is calculated. On reference to a map 2 at its value, the doubling ratio of a torque in a transmission gear and a torque converter is calculated. An already found out target output shaft torque is divided by a torque doubling ratio, and a target engine torque is calculated. A throttle operating amount is calculated according to the target engine torque and the engine speed on reference to a three dimensional map 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a throttle of an automobile having a device for driving the throttle by an actuator.

[0002]

2. Description of the Related Art In conventional vehicles, is the throttle connected to the accelerator pedal by a mechanical link?
Even when the position of the accelerator pedal is detected and the throttle is moved by the actuator based on the signal, the drive torque is not paid attention.

In contrast to these conventional techniques, Japanese Patent Application No. 4-63414 discloses an invention in which a target drive torque is set and a throttle is operated so as to realize the target drive torque. The present invention divides the target drive shaft torque by the gear ratio to calculate the target torque converter output torque, and then uses the torque converter torque ratio calculated from the ratio of the torque converter output rotation and the engine rotation. Calculate the target engine output torque.

[0004]

In the above-mentioned prior art, an electromagnetic pickup is required to detect the output rotation speed of the torque converter, so that the cost is increased and the weight is increased.

An object of the present invention is to provide a method for achieving a target drive torque without directly detecting the output speed of the torque converter.

[0006]

To achieve the above object, the present invention calculates a product of a torque ratio and a gear ratio of a torque converter from a map according to a ratio of engine speed and vehicle speed.

[0007]

By using the above means, the target engine torque can be calculated from the target drive shaft torque without using the output speed of the torque converter, so that the drive torque with good drivability can be realized at low cost.

[0008]

Embodiments of the present invention will be described below.

FIG. 1 is a block diagram of an embodiment of the present invention. First, a three-dimensional map from the vehicle speed and accelerator operation amount 1
And the target drive shaft torque is calculated. Map 1
Is created with reference to the driving torque characteristics of the automobile. The vehicle speed is plotted on the horizontal axis, and the torque characteristic curve corresponding to the accelerator pedal depression angle is arbitrarily set within the maximum torque range. Depending on how to make this map, the torque corresponding to the accelerator pedal depression angle can be achieved, and the feeling of acceleration can be changed arbitrarily.

After the target drive shaft torque is calculated, the target drive shaft torque is divided by the final gear ratio to calculate the target output shaft torque.

On the other hand, the engine speed is divided by the vehicle speed, multiplied by a constant to calculate the rotation ratio, and the map 2 is referred to by that value to calculate the torque multiplication rate in the transmission and the torque converter. The target engine torque is calculated by dividing the already-obtained target output shaft torque by the torque multiplication rate. Map 2
Is calculated from the gear ratio of the transmission and the torque ratio characteristic of the torque converter. The constant is determined by Equation 1.

[0012]

## EQU1 ## Constant = Final gear ratio / (2.pi..tire radius.60) (Equation 1) The throttle operation amount is calculated by referring to the three-dimensional map 3 with the target engine torque and the engine speed. Map 3 is
It can be created by measuring the relationship among engine rotation, engine torque, and throttle opening in advance.

[0013]

According to the present invention, since an arbitrary drive shaft torque can be achieved without a sensor for the output speed of the torque converter, a step in torque can be eliminated, and the ride comfort can be improved at low cost. Release from complicated accelerator work can be realized and driving performance is improved.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

[Explanation of symbols]

1 ... Target drive shaft torque calculation map, 2 ... Torque multiplication rate calculation map, 3 ... Engine performance map.

Claims (1)

[Claims] 1. A method for controlling a throttle opening of an internal combustion engine by a microcomputer, wherein a target drive shaft torque is calculated from a vehicle speed and an accelerator opening, and then a map is calculated according to a ratio of engine speed and vehicle speed. A target engine torque is determined from this value and the target drive shaft torque, and the throttle operation amount is determined according to the target engine torque and engine speed.