JPH04203327A - Throttle control device - Google Patents

Abstract

PURPOSE:To improve throttle valve opening resolution by installing deceleration ratio variation function at a gear train for transmitting the rotation of a motor to a throttle valve shaft. CONSTITUTION:A motor 6 oscillatingly-drives a throttle valve shaft 3 which is provided with a throttle valve 4 for measuring intake air amount of an internal combustion engine. In this constitution, deceleration ratio variation function is provided with a deceleration mechanism 10 for transmitting the rotation of a motor 6 to the throttle valve shaft 3. Namely, the deceleration mechanism 10 is constituted by engaging a driving gear 8 which is provided with a motor shaft 7 with a driven gear 5 which is provided with the throttle valve shaft 3 by a driving small gear 8a and a driven large gear 5a, and a driving large gear 8b and a driven small gear 5b, respectively. By this, output of the motor shaft 7 is transmitted to the throttle valve shaft 3 by large deceleration ratio of the driving small gear 8a and the driven large gear 5a in a small opening range of the throttle valve 4, and small deceleration ratio of the driving large gear 8b and the driven small gear 5b in a large opening range of the throttle valve 4. It is thus possible to improve substantial opening resolution without any sacrifice of quick response at the time of opening deviation of the throttle valve 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric throttle control device suitable for use in an internal combustion engine.

[Conventional technology]

Conventionally, in the throttle control device of an internal combustion engine, in order to improve the resolution of the rotation amount of the throttle valve shaft and reduce the torque required for the drive motor, □Generally, a deceleration is installed between the 3rd throttle 41 motor and the drive motor. A mechanism is in place. (For example, JP-A-1-
253534) The reduction ratio is uniform within the control range.

[Problem to be solved by the invention]

In a throttle control device that measures the intake air amount of an internal combustion engine by swinging and locking a throttle valve shaft equipped with a throttle valve, the resolution of the throttle valve opening degree that determines the intake air amount is It is advantageous for control to be particularly high in the low valve opening range.

On the other hand, if the reduction ratio of the reduction mechanism described above is excessively increased in order to improve this resolution mechanically, there arises the problem that the quick dissolution during the throttle valve shaft drive is deteriorated.

In the conventional technology mentioned above, the reduction ratio of this reduction mechanism is uniform within the control range, so it is difficult to select a reduction ratio that can achieve both high mechanical resolution and high-speed response. .

The present invention aims to improve the throttle valve opening resolution while minimizing the deterioration of fast solubility when driving the throttle valve shaft, and further provides a throttle control device suitable for use in internal combustion engines. The purpose is to

[Means to solve the problem]

The above object is to provide a speed reduction mechanism provided between a throttle valve shaft and a throttle valve shaft driving motor, so that the speed reduction ratio changes to two or more types in accordance with the rotation of the motor shaft. This can be achieved by using a speed reduction mechanism with a speed change function.

[Effect]

If such a mechanism as described above is provided, the motor output will be transmitted to the throttle valve shaft at a large reduction ratio in the throttle valve low opening range and at a small reduction ratio in the throttle valve high opening range.

This is nothing less than increasing the resolution of the drive of the throttle valve shaft in the low opening range of the throttle valve, and increasing the speed of the drive in the high opening range of the throttle valve. Therefore, resolution can be improved while minimizing deterioration in coordination of throttle valve shaft drive.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1, 2, 3, and 4.

FIG. 1 is a structural explanatory diagram of a throttle control device according to the present invention. The throttle body main body 1 forms an air passage 2 and is a support member for a throttle valve shaft 3. The throttle valve 4 is attached to the throttle valve shaft 3 and is swing-locked to open and close the air passage 2 to arbitrarily measure the amount of air taken into the engine.

The motor control means outputs VB from the throttle sensor 9.
A target throttle valve opening is determined from the current throttle valve opening indicated by and information from various sensors, and a motor drive signal P1 is issued to the motor 6. When the motor 6 is driven.

The throttle valve shaft 3 rotates via a speed reduction mechanism 10 composed of a driving gear 8 attached to the motor shaft 7 and a driven gear 5 attached to the throttle valve shaft 3, thereby controlling the target throttle valve opening. do.

FIG. 2 is a detailed explanatory diagram of the speed reduction mechanism 10.

The large gear 5a and small gear 5b of the driven gear 5 attached to the throttle valve shaft 3 have independent fan shapes.

The swing angle of the throttle valve shaft, that is, the control range of the throttle valve opening is limited by this fan shape.

In the speed reduction mechanism 10, a driving gear 8 attached to a motor shaft 7 and a driven gear 5 attached to a throttle valve shaft 3 are configured by a driving small gear 8a, a large driven gear 5a, and a large driving gear 8b and a small driven gear 5b, respectively. The motor shaft 7 is configured by meshing with each other.
transmits the output to the throttle valve shaft 3.

FIG. 3 shows the characteristics of the change in throttle valve opening with respect to the amount of motor rotation.

Diagram A shows the characteristics obtained with the above-mentioned conventional technique, and it is noted that the throttle valve opening resolution is uniform within its control range.

Diagram B shows the characteristics obtained by the present invention, and clearly shows that the throttle valve opening resolution is different in the throttle valve low opening range and the throttle valve high opening range.

In the present invention, in the throttle valve low opening range, the output of the motor shaft 7 is transmitted to the throttle valve shaft 3 by a large reduction ratio made up of the driving small gear 8a and the driven large gear 5a shown in FIG. On the other hand, in the throttle valve high opening range, the output of the motor shaft 7 is transmitted to the throttle valve shaft 3 by a small reduction ratio made up of the driving large gear 8b and the driven small gear 5b. Therefore, in the low throttle valve opening range, the amount of change in the throttle valve opening per unit rotation of the motor shaft 7 is small, and in the high throttle valve opening range, the amount of change in the throttle valve opening per unit rotation of the motor shaft is large. It happens. This is due to the fact that the throttle valve opening resolution is high in the low throttle valve opening range, and the rapid solubility of the throttle valve opening deviation angle is high in the high throttle valve opening range.

FIG. 4 shows the characteristics of the intake air amount and engine output with respect to the throttle valve opening when the engine speed is kept constant and the load is varied.

In the low throttle valve opening range, the amount of change in the amount of intake air relative to the amount of change in the throttle valve opening is large, and in the high throttle valve opening range, the amount of change in the amount of intake air relative to the amount of change in the throttle valve opening is small. Therefore, in a throttle control device whose purpose is to measure the amount of intake air suitable for internal combustion engine operation, high throttle valve opening resolution is required in the low throttle valve opening range, and excessive throttle opening resolution is required in the throttle valve opening range. High throttle valve opening resolution is not required.

As described above, if the speed reduction mechanism according to the present invention is used for transmission between the motor shaft 7 and the throttle valve shaft 3, substantially high throttle valve opening resolution can be obtained without impairing fast solubility during throttle valve opening deviation angle. I can do it.

In this embodiment, the speed change function of the speed reduction mechanism is set to 2 speeds, but it may be set to 3rd speed or higher depending on the characteristics of the target internal combustion engine. Furthermore, a reduction mechanism may be further provided between the motor shaft 7 and the drive gear 8 to provide multi-stage reduction. In this way, the generated torque required for the drive motor can be reduced, and the Miniaturization is also possible.

〔Effect of the invention〕

According to the present invention, in the low throttle valve opening range where high throttle valve opening resolution is required, a large reduction ratio is used to transmit the motor rotation speed to the throttle valve shaft, so that high throttle valve opening resolution can be obtained. I can do it. In addition, in the high throttle valve opening range where high throttle valve opening resolution is not required, the motor rotation speed is transmitted to the throttle valve shaft using a small reduction ratio, so the throttle valve opening resolution must be lowered to the allowable limit. , it is possible to improve the quick solubility when the throttle valve opening angle is changed. Due to the above-mentioned mutual effects, there is an effect that the resolution of the throttle valve opening can be substantially improved without impairing the quick solubility at the time of the throttle valve opening deviation angle.

[Brief explanation of the drawing]

FIG. 1 is a structural explanatory diagram of a throttle control device according to an embodiment of the present invention, FIG. 2 is a detailed explanatory diagram of the speed reduction mechanism 10 of FIG. 1,
FIG. 3 is a diagram showing changes in throttle valve opening with respect to motor rotation amount, and FIG. 4 is a diagram showing changes in engine intake air amount and engine output with respect to throttle valve opening. 1. Throttle body body, 2.. Intake passage, 3..
- Throttle valve shaft, 4 - Throttle valve, 5... Driven gear, 5a... Driven large gear, 5b... Driven small gear, 6... Motor, 7
Motor shaft, 8... Driving gear, 8a... Driving small gear,
8b... Drive large gear, 9... Throttle sensor, 1゛O
・Deceleration mechanism

Claims (1)

[Claims] 1. A throttle valve shaft equipped with a throttle valve used to measure the intake air amount of an internal combustion engine, a motor used to drive the throttle valve shaft in swing, a motor control means used to control the motor, and a motor 1. A throttle control device comprising an electric throttle body comprising a gear train used to transmit the rotation of the throttle valve to a throttle valve shaft, wherein the gear train is provided with a variable reduction ratio function.