JPH04370334A - Throttle actuator - Google Patents

Abstract

PURPOSE:To provide a mechanism particularly suitable for securing safety when a control mechanism or control element is out of order, in an electronic control type throttle actuator. CONSTITUTION:A throttle actuator comprises the first spring 3 which gives torque for closing a throttle valve 5, a first lever 8 provided on a throttle valve axis 2, the second lever 16 operated by an acceleration pedal, the third lever 15 which gives torque for opening the throttle valve 4 from the second lever 16 to the first lever 8, a second spring 14 which pulls the second lever 16 and the third lever 15 to each other, a motor 36 which gives the torque to the valve axis 2, and a clutch 35 which continues discontinues connection between the motor 36 and the valve axis 2.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an electronically controlled throttle actuator that improves control accuracy and provides control flexibility in an intake air amount control mechanism for an engine. The present invention relates to a mechanism suitable for ensuring safety at times.

0002

2. Description of the Related Art An example of a conventional electronically controlled throttle actuator is disclosed in Japanese Patent Laid-Open No. 186022/1983. In this conventional device, the opening degree of the throttle valve is adjusted by adding an operation from an electronically controlled motor to a throttle operation performed by an accelerator pedal via an accelerator cable. The throttle operation of such conventional equipment is
The motor is mainly driven by the accelerator pedal. Normally, the motor is kept in a position where it does not transmit torque to the throttle shaft, and when necessary, it rotates to a position where torque can be transmitted to the throttle shaft, and then changes the throttle valve opening. was under control. For this reason, there is a tendency for a delay in response to occur when starting throttle control, difficulty in adjusting the opening angle at minute angles, and when the motor begins to transmit torque to the throttle shaft, the shock due to the inertial force of the motor is passed through the accelerator pedal. It could not be said that sufficient consideration was given to the impact on drivers.

0003

SUMMARY OF THE INVENTION An object of the present invention is to provide a throttle actuator mechanism that improves the controllability of throttle operation by an actuator such as a motor, and that does not give unnecessary shock to the driver during control. There is a particular thing.

Another object of the present invention is to provide a fail-safe function and a limp-home function that allow the vehicle to be operated safely even if the actuator body or the control device driving the actuator breaks down.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the throttle actuator of the present invention includes a first spring that applies a torque acting on the throttle valve shaft in the direction in which the throttle valve closes, and a first spring that is provided on the throttle valve shaft. a first lever operated by the accelerator pedal, a second lever provided between the two levers and transmitting only the torque from the accelerator pedal in the direction of opening the throttle valve to the first lever. Three levers and
The present invention includes a second spring that pulls the second lever and the third lever together, a motor that applies torque to the throttle valve shaft, and a clutch that connects and disconnects the torque applied from the motor to the throttle valve shaft.

[0006]

[Operation] In the throttle actuator of the present invention, the clutch is normally engaged and the main throttle operation is performed by the motor. The difference between the amount of operation from the accelerator pedal and the amount of operation from the motor is absorbed by the second spring and the relationship between the set positions of the first lever and the third lever. In other words, if the amount of operation from the accelerator pedal is greater than the amount of operation from the motor, the difference will be absorbed by the expansion of the second spring, and conversely, if the amount of operation from the accelerator pedal is greater than the amount of operation from the motor. If it is small, the torque in the direction of opening the throttle valve will not be transmitted to the accelerator pedal due to the relationship between the settings of the first lever and the third lever. Therefore, the throttle actuator of the present invention does not give unnecessary shock to the driver due to throttle operation by the motor.

[0007]Furthermore, a failsafe function and a limp home function are provided in case the motor or the control device that drives the motor fails, for example, if the motor does not perform the desired throttle operation due to a failure of the motor itself or the control device. Since the clutch can be disengaged to separate the motor from the throttle valve shaft and the throttle can be operated using only the accelerator pedal, the vehicle can be moved safely even after a failure occurs.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a sectional view of a first embodiment of the present invention.

A throttle valve shaft 2 is rotatably supported by a bearing 3 in a body 1, which is an intake passage that also serves as a support.
A throttle valve 5 is attached to adjust the opening degree of an intake passage 4 formed therein.

The throttle valve shaft 2 extends on both sides of the body 1, and has a bearing retainer 6, a
Spring collar 7, first lever 8, bearing 9, spring collar 1
0 and a bearing 11 are fixed to the throttle valve shaft 2 by a nut 12. A first spring 13 and a second spring 14 are loosely fitted around the outer peripheries of the spring collars 7 and 10, respectively. Further, a third lever 15 and a second lever 16 are installed on the outer peripheries of the bearing 9 and the bearing 11, respectively, so as to be rotatable with respect to the throttle valve shaft 2, respectively. The second lever 16 is
It is rotated by operating an accelerator pedal 50 via an accelerator cable 51.

Both ends of the first spring 13 are fixed to a pin 17 implanted in the body 1 and a pin 18 implanted in the first lever 8, respectively. The first spring 13 applies a torque to the throttle valve shaft 2 in a direction to close the throttle valve 5 (counterclockwise when viewed from arrow A in FIG. 1). Both ends of the second spring 14 are fixed to a pin 19 implanted in the first lever 8 and a pin 20 implanted in the second lever 16, respectively. The second spring 14 applies a torque to the second lever 16 and the third lever 15 to draw them together.

The first lever 8 has an engaging portion 21 with the third lever 15 , the second lever 16 has an engaging portion 22 with the third lever 15 , and the second lever 16 has an engaging portion 22 with the third lever 15 . is provided with an engaging portion 23 for engaging with the first lever 8 and an engaging portion 24 for engaging with the second lever 16. The positional relationship between the engaging portion 21 and the engaging portion 23 is such that only the torque in the direction of opening the throttle valve 5 (clockwise when viewed from arrow A in FIG. 1) is applied from the third lever 15 to the first lever 8. Conversely, from the first lever 8 to the third lever 15, only torque in the direction of closing the throttle valve 5 (counterclockwise when viewed from arrow A in FIG. 1) can be transmitted. It is set. Furthermore, the positional relationship between the engaging portion 22 and the engaging portion 24 is such that the second lever 16 is connected to the first lever 15 in the direction in which the throttle valve 5 is closed (counterclockwise when viewed from arrow A in FIG. 1). Torque can be directly transmitted through the engaging portions 22 and 24, and the torque in the direction of opening the throttle valve 5 (clockwise when viewed from arrow A in FIG. 1) is
It is set so that it can be transmitted via the second spring 14.

A bearing retainer 25 is fitted onto the other end of the throttle valve shaft 2 (on the right side in FIG. 1) with a threaded portion 26.
The bearing 28 is attached to the nut 29 with the spline section 27 in between.
Fixed by A movable disk 30 is loosely fitted into the spline portion 27 so as to be freely movable in the axial direction of the throttle valve shaft 2, and a gear 31 is provided on the outer periphery of the bearing 28 so as to be rotatable around the throttle valve shaft 2. Bearing 28
A leaf spring 32 is installed between the movable disc 30 and the movable disc 30, and applies a force that presses the movable disc 30 leftward.

A yoke 33 and a coil 34 are fixed to the body 1 on the right end extension of the throttle valve shaft 2.
The movable disc 30, the leaf spring 32, and the gear 31 constitute an electromagnetic clutch 35. The magnetic path includes the yoke 33,
It is formed by a gear 31 and a movable disk 30. When a current flows through the coil 34, the electromagnetic force that tries to attract the movable disc 30 to the right overcomes the spring force of the leaf spring 32, and the movable disc 30 moves until it comes into contact with the gear 31, and the movable disc 30 and gear 31 are separated. Gear 31 due to the frictional force acting between
The torque from the throttle valve shaft 2 is transmitted to the throttle valve shaft 2. When the current flowing through the coil 34 is cut off, the movable disk 30 and the gear 31 are separated by the spring force of the leaf spring 32, and the torque from the gear 31 can no longer be transmitted to the throttle valve shaft 2. The motor 36 is fixed to the body 1, and a pinion 38 that meshes with the gear 31 is attached to the motor shaft 37 through the nut 3.
It is stopped by 9.

Next, the operation of the first embodiment of the present invention will be explained.

First, under normal conditions (when the motor and the control device that drives the motor are operating normally), the coil 34 of the electromagnetic clutch 35 is always energized, that is, the coil 34 of the electromagnetic clutch 35 is always connected to the throttle valve shaft 2 and the motor 36. is in a combined state.

The operation when special throttle control such as traction control or running speed control is not performed will be explained using FIG. 2. Note that FIG. 2 is an explanatory diagram in which the rotational motion of the first embodiment shown in FIG. 1 is replaced with linear motion. For example, in order to realize accelerator opening/throttle opening characteristics such that the amount of depression of the accelerator pedal 50 (hereinafter referred to as accelerator opening) and the opening of the throttle valve 5 (hereinafter referred to as throttle opening) are proportional, it is necessary to If the rotation angle of the motor 36 is controlled so that the accelerator opening signal from a sensor (not shown) that detects the opening matches the throttle opening signal from a sensor (not shown) that detects the throttle opening. good. At this time, since the accelerator opening degree, that is, the rotation angle of the second lever 16 and the rotation angle of the throttle valve shaft 2 are equal, the first lever 8 and the second lever 1
6, and the third lever 15 have engaging parts 21, 22, 2
3, and 24, they always move in contact with each other. FIG. 3 shows the relationship between the accelerator opening and the throttle opening when the above control is performed.

Next, the operation when throttle control such as traction control and traveling speed control is performed will be explained.

[0020] An example of the positional relationship of the first lever, second lever, and third lever when performing throttle control that reduces the throttle opening compared to the accelerator opening, as typified by traction control. Shown in Figure 4. Further, FIG. 5 shows the relationship between the accelerator opening and the throttle opening when such control to close the throttle valve is performed. In FIG. 5, the shaded range represents the throttle opening that can occur due to control.

[0021] Accelerator opening, that is, second lever 1
For the opening of 6, the throttle opening, that is, the motor 36
The opening degree of the throttle valve 5 driven by is small. This difference in opening between the two is absorbed by the extension of the second spring 14. At this time, the change in the accelerator pedal depression force felt by the driver is equal to the torque generated by the expansion of the second spring 14. Therefore, by choosing the spring constant of the second spring 14 to be smaller than the spring constant of the first spring 13, the proportion of the change in accelerator pedal depression force caused by throttle control in the total accelerator pedal depression force can be reduced. , it is possible to make the driver hardly feel any change in the accelerator pedal depression force. This prevents unnecessary shock from being given to the driver even when throttle control is performed to reduce the throttle opening relative to the accelerator opening.

Next, FIG. 6 shows an example of the positional relationship of the first lever, second lever, and third lever when throttle control is performed to make the throttle opening larger than the accelerator opening. show. Such a situation occurs when the vehicle's running speed is controlled. FIG. 7 shows the relationship between the accelerator opening and the throttle opening when the throttle valve is controlled to open. In FIG. 7, the shaded range represents the throttle opening degree that can occur due to control.

The throttle opening, that is, the motor 36
The opening degree of the throttle valve 5 driven by is large. At this time, both levers are installed so that only the torque in the direction of closing the throttle valve 5 (toward the right in FIG. 6) is transmitted from the first lever 8 to the third lever 15. Therefore, even if the throttle opening becomes larger than the accelerator opening due to throttle control, this opening difference has no effect on the second lever 16 connected to the accelerator pedal 50 operated by the driver. In this way, even when throttle control is performed to increase the throttle opening relative to the accelerator opening, no unnecessary shock is given to the driver.

The throttle actuator of the present invention allows the throttle opening to be arbitrarily controlled by throttle control at any accelerator opening, and the control does not give an unnecessary shock to the driver. FIG. 8 shows the relationship between the accelerator opening and the throttle opening when throttle control is performed using the throttle actuator of the present invention. In FIG. 8, the shaded range represents the throttle opening that can be controlled.

Next, the failsafe function and limp home function in case the motor or the control device that drives the motor breaks down will be explained below.

Failure of the throttle actuator of the present invention is caused by a malfunction in the motor 36 itself due to sticking or disconnection, or a malfunction in the control device that controls the motor 36.
It is possible that the motor 36 does not perform the desired throttle operation. However, in any case, as shown in FIG. 9, by disengaging the electromagnetic clutch 35 and separating the motor 36 from the throttle valve 5, the throttle operation can be performed using only the accelerator pedal 50. You can safely move your car afterwards.

At this time, the magnitude of the initial strain of the second spring 14 is determined by the amount of the second spring 14 generated by the initial strain.
If the torque that draws the second lever 16 and the third lever 15 together is set to be greater than the torque (maximum torque) generated by the first spring 13 when the throttle valve 5 is fully opened, all accelerator openings (throttle opening), the third lever 15 moves together with the second lever 16, so there is no delay in the response of the throttle valve 5 to the driver's accelerator pedal operation. Furthermore, when the accelerator opening is fully open, the throttle opening is also fully open, so there is no restriction on the throttle opening range that the driver can operate in the event of a failure. FIG. 10 shows the relationship between the accelerator opening and the throttle opening at the time of failure.

Further, as described above, the electromagnetic clutch 35 connects the motor 36 and the throttle valve shaft 2 only when the electromagnetic clutch 35 is energized, and maintains the motor 36 and the throttle valve shaft 2 in a disconnected state when the electromagnetic clutch 35 is not energized. Therefore, in the event of a failure of the motor 36 or the control device, the motor 36 can be easily disconnected from the throttle valve 5 by simply cutting off the power to the electromagnetic clutch 35, and the fail-safe function and limp home function are immediately realized. can do. Furthermore, even in the unlikely event that a malfunction occurs such as a disconnection of the power supply line to the electromagnetic clutch 35, the electromagnetic clutch 35 will be disconnected and the throttle valve 5 can be operated using the accelerator pedal 50. No problems will arise that will cause trouble.

FIG. 11 shows a sectional view of a second embodiment of the present invention.

First, the difference in configuration from the first embodiment shown in FIG. 1 will be explained. In the second embodiment shown in FIG.
A spring collar 40 is inserted into the motor shaft 37, and a third spring 41 is installed around the outer periphery of the spring collar 40. Both ends of the third spring 41 are fastened to a pin 42 and a pin 43 that are embedded in the body of the motor 36 and the pinion 38, respectively. This third spring 41 applies torque to the motor shaft 37 in the direction of closing the throttle valve 5 (counterclockwise when viewed from arrow B in FIG. 11).

The difference between the second embodiment and the first embodiment lies in the operation when the electromagnetic clutch 35 fails. If a failure occurs in the electromagnetic clutch 35 and it becomes impossible to disconnect the motor 36 and the throttle valve shaft 2, the control of the motor 36 is terminated, that is, the motor shaft 37 is stopped by cutting off the power to the motor 36. When the throttle valve shaft 2 is rotated by operating the accelerator pedal 50, the motor shaft 37 is also rotated. At this time, in addition to the throttle valve shaft 2 and the throttle valve 5 as rotating parts, the gear 31,
Since the pinion 38 and motor shaft 37 increase, the moment of inertia increases. In the first embodiment, the torque that closes the throttle valve is generated only by the first spring 13, so if the moment of inertia increases, there is a risk that the time required to close the throttle valve will become longer. At this time, in the first embodiment as well, if a spring with a large spring constant is used as the first spring 13, the throttle valve can be closed in response to the movement of the accelerator pedal even if the moment of inertia increases. However, in this case,
Even when the electromagnetic clutch 35 operates normally and the motor 36 can be disconnected, the accelerator pedal depression force required to operate the throttle valve with the accelerator pedal increases, that is, the accelerator pedal becomes heavy.

On the other hand, in the second embodiment, the electromagnetic clutch 35
When the motor 36 and the throttle valve 5 cannot be separated due to failure and the moment of inertia increases, not only the first spring 13 but also the third spring 41 generates a torque in the direction of closing the throttle valve 5. Therefore, there is no response delay. Figure 12 is an explanatory diagram of the operation at this time.
Shown below. Further, when the electromagnetic clutch 35 operates normally and the motor 36 can be disconnected, only the first spring 13 applies torque as shown in FIG. 13, so the accelerator pedal does not become heavy.

Regarding the weight that the driver feels when stepping on the accelerator pedal, is it better that there is no change between when there is a failure and when it is normal, or is it better to have it change when a failure occurs and make the driver aware of the failure? Whether it is good or not is determined in the design of the entire system. However, in either case, either requirement can be satisfied by selectively using the first embodiment or the second embodiment proposed by the present invention.

At this time, the second lever 16 and the third lever 1 generated by the initial strain of the second spring 14
5 is set to be larger than the sum of the torques generated by the first spring 13 and the third spring 41 when the throttle valve 5 is fully opened, the Three levers 15
Since it moves in unison with the second lever 16, there is no delay in the response of the throttle valve 5 to the driver's operation of the accelerator pedal. Further, when the accelerator opening is fully open, the throttle opening is also fully open, so there is no restriction on the throttle opening range that the driver can operate in the event of a failure.

[0035]

[Effects of the Invention] The throttle actuator of the present invention has the following features:
Normally, the main throttle operation is performed by the motor with the clutch in the engaged state, and the difference between the amount of operation from the accelerator pedal and the amount of operation from the motor is determined by the second spring and the setting positions of the first and third levers. Since the shock is absorbed by the relationship, unnecessary shock is not given to the driver by throttle control by the motor.

Furthermore, as for the fail-safe function and limp-home function in case the motor or the control device that drives the motor breaks down, the clutch is disengaged, the motor is separated from the throttle valve shaft, and the throttle is operated only by the accelerator pedal. This allows the vehicle to be moved safely even after a breakdown occurs.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of the operation of the first embodiment.

FIG. 3 is a characteristic diagram of the accelerator opening and throttle opening when the throttle opening is controlled to be equal to the accelerator opening.

FIG. 4 is an explanatory diagram of the operation when the throttle opening is controlled to be smaller than the accelerator opening.

FIG. 5 is a characteristic diagram of the accelerator opening and the throttle opening when the throttle opening is controlled to be smaller than the accelerator opening.

FIG. 6 is an explanatory diagram of the operation when the throttle opening is controlled to be larger than the accelerator opening.

FIG. 7 is a characteristic diagram of the accelerator opening and the throttle opening when the throttle opening is controlled to be larger than the accelerator opening.

FIG. 8 is a characteristic diagram of accelerator opening and throttle opening when throttle control is performed using the throttle actuator of the present invention.

FIG. 9 is an explanatory diagram of the operation when an accelerator pedal is operated at the time of a failure.

FIG. 10 is a characteristic diagram of accelerator opening and throttle opening at the time of failure.

FIG. 11 is a sectional view of a second embodiment of the present invention.

FIG. 12 is an explanatory diagram of the operation when the electromagnetic clutch cannot be disconnected in the second embodiment.

FIG. 13 is an explanatory diagram of the operation when the electromagnetic clutch operates normally in the second embodiment.

[Explanation of symbols]

1...Body, 2...Throttle valve shaft, 4...Intake passage,
5... Throttle valve, 8... First lever, 13... First spring, 14... Second spring, 15... Third lever, 16
...Second lever, 21, 22, 23, 24...Fitting part, 3
1... Gear, 35... Electromagnetic clutch, 36... Motor, 38...
Pinion, 41...Third spring.

Claims (1)

[Claims] 1. A first spring that applies a torque acting in a direction in which the throttle valve closes to a throttle valve shaft, a first lever provided on the throttle valve shaft, and a second lever operated by an accelerator pedal. a third lever that is provided between the first lever and the second lever and transmits only the torque from the accelerator pedal in the direction of opening the throttle valve to the first lever; A second spring that pulls together the second lever and the third lever, a motor that applies torque to the throttle valve shaft, and a clutch that connects and disconnects the torque applied from the motor to the throttle valve shaft. Features a throttle actuator.