JPH0941994A - Throttle valve controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold a second throttle valve in small opening when a first throttle valve is full open by energizing force of a first energizing means and to hold the second throttle valve at a full-open position when the first throttle valve is in a closed position, in the time of motor trouble thereby to reduce in the torque in a motor for opening or closing the second throttle valve. SOLUTION: In the case where a motor 36 gets out of order and thereby torque from this motor 36 is not transmitted to a sub shaft 32 of a sub valve 31 or a second throttle valve, enegization of return spring 35 or a first energizing means holds an extent of opening in this sub valve 31 to the small opening of 10 degrees or so even in the case where a main valve 21 is fully opened, and a rate of intake flow running in an inlet passage 12 comes to the maximum. In addition, when the main valve 21 is in the full-open position, the sub valve 31 is set up so as to make it be held at the full-open position. With this, the torque of the motor 36 opening or closing and driving this sub valve 31 can be lessened, insofar as possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve control device for adjusting the amount of air taken into an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, a main valve mechanically connected to an accelerator pedal and a sub-valve that is driven to open and close by a motor based on a control signal from an electronic control unit (hereinafter, "electronic control unit" is referred to as ECU) are provided. As a throttle valve control device provided in an intake passage of an internal combustion engine (hereinafter, "internal combustion engine" is referred to as an engine)
The one disclosed in the publication is known.

In such a throttle valve control device having the main valve and the sub-valve in the intake passage, the main valve is opened and closed mechanically according to the amount of depression of the accelerator pedal by the driver, and the detection signals from various sensors are used. The ECU grasps the engine operating state based on this, and the amount of air taken into the engine is adjusted by the sub-valve opened / closed by the motor according to the control signal from the ECU. However,
For example, when the tire runs idle due to sudden start or snowy road and the grip force with the road surface decreases, the ECU detects the idling of the tire by a detection signal from a sensor that detects the number of rotations of the tire, A control signal is sent to the sub valve to rotate it in the closing direction. As a result, the engine speed is reduced and the tire is prevented from idling. In this way, by adjusting the opening degree of the sub-valve according to the driving state of the vehicle and the like, the grip force of the tire with respect to the road surface is ensured, and safe driving is possible. Also, even if the motor fails and the driving force (hereinafter "driving force" is referred to as torque) is no longer transmitted to the sub-valve, a return spring is provided to bias the sub-valve in the fully open direction. The main valve is opened and closed to allow the vehicle to run.

[0004]

However, in the conventional throttle valve control device as described above, the biasing force of the return spring that biases the sub valve in the opening direction is such that the main valve is fully opened and the air flow rate in the intake passage is maximum. Even if it becomes, the size is set so that the sub valve can be fully opened from any opening. Therefore, in order for the motor to rotate the sub valve in the closing direction against the biasing force of the return spring during normal operation of the motor, it is necessary to transmit a large torque to the sub valve. To generate this large torque, increase the torque of the motor itself,
It is conceivable to reduce the gear on the sub-valve side with respect to the motor side, that is, to increase the gear diameter on the sub-valve side relative to the motor side so that the torque transmitted to the sub-valve is larger than the torque generated by the motor. However, there is a problem in that the size of the motor increases and the size of the device itself increases. Also, there is a problem that the responsiveness of the sub-valve is lowered because the rotation speed of the sub-valve is reduced. Furthermore, since gears are used on the motor side and the sub-valve side, there is a problem that the number of parts increases and the manufacturing cost increases.

The present invention has been made to solve such a problem, and an object thereof is to provide a throttle valve control device which can be miniaturized. Another object of the present invention is to
An object of the present invention is to provide an inexpensive throttle valve control device having good responsiveness and a small number of parts.

[0006]

[Means for Solving the Problems]

(Solution) A throttle valve control device according to claim 1 of the present invention for achieving the above object, is provided with a first throttle valve and a second throttle valve in an intake passage of an engine for intake to the engine. A throttle valve control device for adjusting an air amount, wherein the first throttle valve is opened / closed in conjunction with an accelerator pedal, and a motor for opening / closing the second throttle valve based on a control signal from the control device. And a first urging means for urging the second throttle valve in the opening direction, wherein the torque of the motor is not transmitted to the second throttle valve and the first urging means is activated when the motor fails. The urging force of the urging means is smaller than the opening degree at which the second throttle valve receives the maximum force in the closing direction from the air flow flowing through the intake passage when the first throttle valve is fully opened. The slot Holding the Le valve, the first throttle valve is characterized in that it is set to retain the fully open position the second throttle valve to be in a fully closed position.

A throttle valve control device according to a second aspect of the present invention is the throttle valve control device according to the first aspect, further comprising a rotation angle sensor for detecting an opening degree of the second throttle valve, The urging force of the second urging means for urging the sensor to the rotation reference position urges the second throttle valve in the opening direction. According to a third aspect of the present invention, there is provided a throttle valve control device according to the first or second aspect.
In the throttle valve control device described above, the torque transmission ratio from the motor to the second throttle valve is approximately 1: 1.
It is characterized by being.

(Operation and Effect of the Invention) According to the throttle valve control device of the first aspect of the present invention, the first throttle valve and the second throttle valve are arranged in the intake passage of the engine to connect to the engine. Adjusting the air flow rate. When the motor fails and the torque of the motor is not transmitted to the second throttle valve, the urging force of the first urging means for urging the second throttle valve in the opening direction is such that the first throttle valve is fully opened. Since the second throttle valve is set to a size that holds the second throttle valve at an opening smaller than the opening at which the second throttle valve receives the maximum force in the closing direction from the air flow flowing through the intake air passage, The biasing force of the biasing means is reduced.
For this reason, the torque of the motor that drives the second throttle valve to open and close can be reduced, so that the motor can be downsized and the size of the device can be reduced.

According to a second aspect of the present invention, there is provided a throttle valve control device, which has a rotation angle sensor for detecting the opening of the second throttle valve, and the second rotation angle sensor biases the rotation angle sensor to the rotation reference position. The urging force of the urging means urging the second throttle valve in the opening direction can further reduce the urging force of the first urging means in the opening direction, so that the torque of the motor can be further reduced.

According to the third aspect of the throttle valve control apparatus of the present invention, the torque transmission ratio from the motor to the second throttle valve is set to approximately 1: 1, so that the motor side and the second throttle valve side are provided. Manufacturing costs are reduced because parts such as gears that reduce the torque transmission ratio are unnecessary. Further, since the rotation speed of the motor is transmitted to the second throttle valve at a ratio of about 1: 1, the response of the second throttle valve is improved.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. An embodiment of the throttle valve control device of the present invention is shown in FIG. The main valve 21, which is the first throttle valve, is fixed to the main shaft 22 and rotates together with the main shaft 22. The main shaft 22 is rotatably supported by bearings 23. Oil seals 24 are arranged around the main shaft 22 on both ends of the main shaft 22 of the bearing 23. The throttle lever 25 is connected to an accelerator pedal (not shown) by a wire or the like, and the main valve 21 opens and closes in conjunction with the depression amount of the accelerator pedal. Main shaft 2
Two return springs 26 provided at one end of the second valve 2 have one end fixed to the throttle body 11 and the other end fixed to the main shaft 22. The return spring 26 urges the main valve 21 in the closing direction. In the present embodiment, two return springs 26 are provided so that one return spring 26 is deficient and the other return spring 26 urges the main valve 21 in the closing direction. Further, a potentiometer 27 is attached to the outside of the end of the main shaft 22. The potentiometer 27 has a main valve 21.
Is for detecting the rotational angle position of the above, and the detected angle detection signal is sent to an ECU (not shown). The potentiometer 27 has a built-in return spring (not shown) that returns the potentiometer 27 to the rotation reference position.
The biasing force of this return spring is the main shaft 22.
Works to urge in the closing direction. The fully closed position of the main valve 21 is regulated by a fully closed stopper 28.

On the upstream side of the inflow air of the main valve 21, a sub valve 31 as a second throttle valve which is fixed to the sub shaft 32 and rotates together with the sub shaft 32 is provided. Sub-shaft 32 is throttle body 1
It is rotatably supported by a bearing 33 attached to the No. 1. An oil seal 34 is arranged around the sub shaft 32 inside the bearing 33 in the sub valve 32 direction.

One end of the return spring 35 is fixed to the throttle body 11 and the other end is fixed to the sub shaft 32. The return spring 35 urges the sub valve 31 in the opening direction. Sub shaft 3
A motor 36 for controlling the opening and closing of the sub-valve 31 in response to a control signal from the ECU is provided at one end of 2.
As shown in FIG. 2, the tip portion 3 of the rotary shaft 37 of the motor 36
7a is formed in an oval cross section by notching both sides in the radial direction in the axial direction. Further, a concave portion 38a is formed in the tip portion 38 of the sub-shaft 32 so that the tip portion 37a of the rotary shaft 37 can be fitted therein.
Are formed. Since the rotating shaft 37 and the tip portion 38 are formed to have substantially the same diameter, the motor 36 and the sub shaft 3 are
Torque is transmitted to 2 in a relationship of approximately 1: 1.

A potentiometer 39 is arranged on the side of the sub-shaft 32 opposite to the motor. Potentiometer 3
Reference numeral 9 is for detecting the rotational angular position of the sub-valve 31, and sends the detected angle detection signal to the ECU. The potentiometer 39 has a built-in return spring (not shown) as second biasing means for returning the potentiometer 39 to the rotation reference position. The biasing force of the return spring acts to bias the sub shaft 32 in the opening direction.

Next, the operation of the throttle valve control device 10 will be described. (1) When the motor is normal During normal driving, the air flow rate of the engine opens and closes according to the amount of depression of the accelerator pedal.
6 is adjusted by the sub valve 31 which is opened and closed by the drive valve 6. When a tire runs idle due to sudden start or running on a snowy road, and the grip force of the tire decreases against the road surface, a sensor that detects the number of rotations of the tire sends a detection signal to the ECU. The idle rotation of the tire is detected based on the signal, and the motor 36 is driven to rotate the sub valve 31 in the closing direction. Then, the amount of air taken into the engine is reduced and the engine speed is reduced to restore the grip force of the tire to the road surface. When the grip force of the tire increases, the sub valve 31 is rotated in the opening direction.

In such opening / closing control of the sub-valve 31, the motor 36 receives rotational resistance in both the opening direction and the closing direction due to the rotational resistance of the motor itself and the bearing resistance of the sub-shaft 32. Since the sub-valve 31 receives a force in the closing direction by the air flow in the intake passage 12, the motor 36 is rotated in order to rotate the sub-valve 31 in the opening direction.
Is the rotation resistance of the motor 36 itself and the sub shaft 32.
In addition to the bearing resistance of the sub valve 31, the sub valve 31 must be rotated in the opening direction against the force received from the air flow.

Further, in order to rotate the sub-valve 31 in the closing direction, the motor 36 resists the rotational resistance of the motor 36 and the bearing resistance of the sub-shaft 32 as well as the urging force of the return spring 35 and the return spring built in the potentiometer 39. Then, the sub valve 31 must be rotated in the closing direction. In the present embodiment, the force that the sub valve 31 receives in the opening direction by subtracting the rotation resistance from the return spring 35 and the return spring built in the potentiometer 39 is the maximum force that the sub valve 31 receives in the closing direction from the air flow flowing through the intake passage 12. Smaller than.

(2) At the time of motor failure When the motor 36 fails and the torque from the motor 36 is not transmitted to the sub-shaft 32, the return spring 3
5 and the return spring built in the potentiometer 39 urges the sub valve 31 in the opening direction.
Even when the main valve 21 is fully opened and the intake flow rate flowing through the intake passage 12 is maximized, the opening degree of the sub valve 31 is set to about 10 °. If the opening degree of the sub-valve 31 is set to about 10 °, the main valve 2 that opens and closes according to the depression amount of the accelerator pedal
1 allows the vehicle to travel at a maximum speed of about 100 km / h, so it is possible to bring the vehicle to a repair shop or the like.

Generally, the disc-shaped throttle valve receives the largest force from the air flow in the closing direction when the opening is about 40 to 50 °, and the opening becomes smaller or larger than this range. Accordingly, the force received in the closing direction becomes smaller. Therefore, the force required to maintain the opening of the sub-valve 31 at 10 ° is smaller than 40 to 50 °, and the biasing force of the return spring 35 is small. Further, since the return spring built in the potentiometer 39 also urges the sub valve 31 in the opening direction, the opening of the sub valve 31 is kept at 10 ° by the sum of the urging forces of the return spring 35 and the return spring built in the potentiometer 39. As long as it is possible, the biasing force of the return spring 35 can be further reduced. As a result, when the motor is operating normally, the torque for controlling the opening / closing of the sub valve 31 can be reduced, so that the motor 36 can be downsized.

Once the accelerator pedal is released, the main valve 2
If the flow rate of the air flowing through the intake passage 12 is reduced by rotating 1 to the fully closed position and the force in the closing direction acting on the sub-valve 31 is reduced, the return spring 35 and the return spring built in the potentiometer 39 are opened in the opening direction. The sub-valve 31 is held in the fully open position by the urging force of. Then, the valve surface of the sub-valve 31 becomes substantially parallel to the air flow, and the sub-valve 31 receives almost no force from the air flow in the closing direction. Therefore, even if the main valve 21 is fully opened, the sub-valve 31 should keep the fully open position. You can As a result, the vehicle can normally run by controlling the opening / closing of the main valve 21 by operating the accelerator pedal.

The effect of this embodiment will be described in comparison with the comparative example shown in FIGS. In the comparative example, the same motor as the motor of this example is used. In the throttle valve control device 40 according to the comparative example shown in FIGS. 3 and 4, the biasing force of the return spring built in the potentiometer 39 biases the sub valve 31 in the closing direction. Further, the biasing force of the return spring 41 has a biasing force capable of rotating the sub valve 31 to the fully open position even when the main valve 21 is at the fully open position when the motor 36 fails. Therefore, the return spring 41 that biases the sub valve 31 in the opening direction
Is larger than the biasing force of the return spring 35 of this embodiment.

During normal operation of the motor 36, a large torque is required to control the opening / closing of the sub valve 31 against the biasing force of the return spring 41 and the return spring built in the potentiometer 39. In order to generate a large torque, in the comparative example, as shown in FIG.
A motor gear 43 is attached to the rotary shaft 37 of the motor 36, and a valve gear 44 is attached to the sub shaft 32. The gear ratio of the motor gear 43 to the valve gear 44 is set to, for example, motor gear: valve gear = 1: 3. As a result, the sub valve 3 can be provided without increasing the size of the motor 36
Although the torque transmitted to No. 1 can be increased, there is a problem that the response speed of the sub-valve 31 decreases because the torque transmission speed decreases.

On the other hand, in this embodiment, when the motor malfunctions, even if the main valve 21 is at the fully open position, the opening of the sub valve 31 is maintained at about 10 ° to return the sub valve 31 to the opening direction. Spring 35
The biasing force of can be reduced. Further, the biasing force of the spring built in the potentiometer 39 acts in the opening direction of the sub valve, so that the return spring 3
The biasing force of 5 can be further reduced. As a result, the torque for driving the sub-valve 31 to open and close decreases, so that the motor 36
Since it is not necessary to set a gear or the like in the torque transmission path from the sub shaft 32 to the sub shaft 32, the torque transmission ratio can be made approximately 1: 1. For this reason, parts such as a motor gear or a valve gear are reduced, the device can be easily manufactured, and the responsiveness of the sub valve 31 is improved. On the contrary, by using a gear or the like, it is possible to further reduce the torque generated by the motor and further downsize the motor.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a throttle valve control device of the present invention.

FIG. 2 is a schematic diagram showing a connection structure between a sub shaft and a motor rotating shaft.

FIG. 3 is a cross-sectional view showing a comparative example of this embodiment.

FIG. 4 is a schematic diagram showing a torque transmission structure from a motor of a comparative example to a sub shaft.

[Explanation of symbols]

 10 Throttle valve control device 11 Throttle body 12 Intake passage 21 Main valve (first throttle valve) 31 Sub valve (second throttle valve) 35 Return spring (first biasing means) 36 Motor 39 Potentiometer (rotation angle sensor)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kenji Sugiyama 1-1-1 Showa-cho, Kariya-shi, Aichi Prefecture Nippon Denso Co., Ltd.

Claims (3)

[Claims] 1. A throttle valve control device for arranging a first throttle valve and a second throttle valve in an intake passage of an internal combustion engine to adjust the amount of air taken into the internal combustion engine, wherein the first throttle valve is provided. The valve opens and closes in conjunction with the accelerator pedal, and a motor that drives the second throttle valve to open and close based on a control signal from the control device and a first actuator that biases the second throttle valve in the opening direction. Urging means, the driving force of the motor is not transmitted to the second throttle valve, the urging force of the first urging means is set when the first throttle valve is fully opened, when the motor fails. The second throttle valve is held at an opening smaller than the opening at which the second throttle valve receives the maximum force in the closing direction from the air flow flowing through the intake passage, and the first throttle valve is in the fully closed position. If the second A throttle valve control device, characterized in that it is set to hold the rottle valve in a fully open position. 2. A urging force of a second urging means for urging the rotation angle sensor to a rotation reference position, comprising a rotation angle sensor for detecting an opening of the second throttle valve. 2. The throttle valve control device according to claim 1, wherein the throttle valve is biased in the opening direction. 3. The throttle valve control device according to claim 1, wherein a driving force transmission ratio from the motor to the second throttle valve is approximately 1: 1.