JP2917727B2 - Electronic throttle drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic throttle driving device for controlling the opening and closing of a throttle valve by a motor, and more particularly, the opening and closing operation of the throttle valve can be controlled by an accelerator pedal via a first electromagnetic clutch. The invention also relates to an electronic throttle drive device that can be electronically controlled by a motor via a second electromagnetic clutch.

[0002]

2. Description of the Related Art In this type of electronic throttle driving device, an accelerator drum connected to one end of an accelerator wire via a first electromagnetic clutch is provided on one of the rotation shafts of a throttle valve incorporated in a throttle body. In addition, a motor for opening and closing the throttle valve is provided on the other of the rotation shafts of the throttle valve via a second electromagnetic clutch. When the power supply to one of the electromagnetic clutches is stopped due to, for example, a break in a connection line for supplying power to the first or second electromagnetic clutch, the power supply to the other electromagnetic clutch is stopped. The electromagnetic coils of the first and second electromagnetic clutches are electrically connected so that the supply is also stopped, the first electromagnetic clutch is connected, the second electromagnetic clutch is released, and the throttle valve can be opened and closed by the accelerator pedal. Are connected in series. When the opening and closing of the throttle valve is electronically controlled by a motor via a second electromagnetic clutch, for example, constant speed traveling control can be performed so as to maintain the vehicle speed at a desired set speed. When the electronic control is released, the operation of the accelerator drum corresponding to the operation of the accelerator pedal is transmitted to the throttle valve via the first electromagnetic clutch by operating the accelerator pedal connected to the other end of the accelerator wire to thereby control the throttle valve. The valve is controlled to open and close, and performs an opening and closing operation in accordance with the operation of an accelerator pedal.

[0003] More specifically, the throttle valve is biased by a return spring to be always closed. The motor and the first and second electromagnetic clutches are controlled by an electronic controller. Normally, the first electromagnetic clutch is disconnected, the second electromagnetic clutch is connected, and the opening and closing of the throttle valve is controlled by the motor.

When the electronic controller finds an abnormality in the motor or the like, it disconnects the second electromagnetic clutch, connects the first electromagnetic clutch, and performs control so as to switch the operation to an accelerator pedal.

[0005]

As described above, in the conventional electronic throttle driving device, when the second electromagnetic clutch is disconnected and the first electromagnetic clutch is to be connected when an abnormality is found, for example, Since the first electromagnetic clutch and the second electromagnetic clutch are electrically connected in series, power is supplied to the second electromagnetic clutch for disconnecting the second electromagnetic clutch and the first electromagnetic clutch is connected. And the second electromagnetic clutch is disconnected earlier than the first electromagnetic clutch is connected, and the throttle valve is connected to both the motor and the accelerator drum. A state where the throttle valve is not connected occurs, and during this time, the throttle valve rotates in the closing direction by the return spring. As a result, there is a problem that the engine of the vehicle changes unexpectedly, and the commercial value is deteriorated.

[0006] The present invention has been made in view of the above,
An object of the present invention is to provide an electronic throttle drive device that prevents an unnecessary change in the throttle valve opening when switching an electromagnetic clutch.

[0007]

In order to achieve the above object, an electronic throttle driving device according to the present invention comprises a throttle valve provided on a throttle body and an accelerator lever interlocked with the throttle valve and an accelerator pedal. A first electromagnetic clutch which is brought into a connected state by a biasing force of a spring when the electromagnetic coil is not energized, and is opened by a magnetic force of the electromagnetic coil when the electromagnetic coil is energized; An electromagnetic coil electrically connected in series with the electromagnetic coil and disposed between the throttle valve and the motor; when the electromagnetic coil is energized, it is connected by the magnetic force of the electromagnetic coil, and the electromagnetic coil is de-energized; A second electromagnetic clutch that is sometimes released by the biasing force of a spring, and the first and second electromagnetic clutches Control means for controlling energization and de-energization of the motor and rotation of the motor, and timing for switching the second electromagnetic clutch from the connected state to the released state, and timing for switching the first electromagnetic clutch from the released state to the connected state. And a delay means for delaying the data.

[0008]

According to the electronic throttle drive of the present invention, the second
The timing at which the first electromagnetic clutch is switched from the connected state to the released state is delayed from the timing at which the first electromagnetic clutch is switched from the released state to the connected state.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the structure of an electronic throttle drive device according to one embodiment of the present invention. The electronic throttle driving device 10 shown in FIG. 1 has a normally open type first electromagnetic clutch 3 for transmitting the operation amount of the accelerator pedal to the throttle valve 1 on the left side of the throttle valve 1 and controls the rotation of the DC motor 7. A normally closed second electromagnetic clutch 5 for transmitting to the throttle valve 1 is provided on the right side of the throttle valve 1, and the electronic controller (not shown) opens and closes the throttle valve 1 via the DC motor 7 and the second electromagnetic clutch 5. By performing electronic control, automatic constant speed traveling control (ASCD) can be performed without using an accelerator pedal, and the operation amount of the accelerator pedal is transmitted to the throttle valve 1 via the first electromagnetic clutch 3. To control driving force characteristics by accelerator pedal (accelerator-by-wire system) ) Can be carried out.

The first electromagnetic clutch 3 has an accelerator drum 13 connected to an accelerator pedal (not shown) via an accelerator wire 11, and a first electromagnetic clutch plate 15 which comes into contact with and separates from the accelerator drum 13. This first
Electromagnetic clutch plate 15 is biased by the first clutch biasing spring 17 having a spring constant K _1. Further, a first electromagnetic clutch coil 19 is provided near the first electromagnetic clutch plate 15, and when the first electromagnetic clutch coil 19 is energized, the first electromagnetic clutch coil 19 is turned off.
When the first electromagnetic clutch plate 15 is attracted by the magnetic force of the electromagnetic clutch coil 19 to separate the first electromagnetic clutch plate 15 from the accelerator drum 13 and the first electromagnetic clutch coil 19 is turned off,
The first electromagnetic clutch plate 15 is pressed by the accelerator drum 13 by the urging force of the first clutch urging spring 17.
To be connected to.

The first electromagnetic clutch 3 has a throttle valve return spring 9 for urging the throttle valve 1 in a closing direction. Further, the accelerator drum 13 is provided with an accelerator drum return spring 14, and an accelerator sensor 12a and a throttle sensor 12b are provided near the accelerator spring.

On the other hand, the second electromagnetic clutch 5 has a DC motor 7 whose rotation is controlled by an electronic controller (not shown). The rotation of the DC motor 7 is transmitted to a clutch connecting plate 23 via a reduction gear 21. It has become. This is the clutch connecting plate 23 are disposed a second electromagnetic clutch plates 25 are opposed by the second electromagnetic clutch plates 25 and the second clutch biasing spring 27 having the spring constant K ₂ It is biased and disconnected from the clutch connecting plate 23 in a normal state. In addition, the second electromagnetic clutch plate 2
5, a second electromagnetic clutch coil 29 is provided on the side opposite to the clutch connecting plate 23, and when the second electromagnetic clutch coil 29 is energized, the magnetic force of the second electromagnetic clutch coil 29 is increased. The clutch coupling plate 23 is attracted by the second electromagnetic clutch plate 2
5 is connected to the clutch connecting plate 23, whereby the rotation of the DC motor 7 is transmitted to the throttle valve 1 via the reduction gear 21, the clutch connecting plate 23, and the second electromagnetic clutch plate 25. Opening and closing can be controlled according to the rotation of the DC motor 7. When the second electromagnetic clutch coil 29 is de-energized, the clutch connecting plate 23 is separated from the second electromagnetic clutch plate 25 by the urging force of the second clutch urging spring 27.

FIG. 2 is a system configuration diagram using the electronic throttle drive device 10 shown in FIG. The electronic throttle driving device 10 shown in FIG. 1 is shown on the right side in FIG.
Is connected to the accelerator pedal 31 via
The C motor 7 is connected to a motor drive circuit 33b of the electronic controller 33 via a pair of cables 32. The first electromagnetic clutch coil 19 and the second electromagnetic clutch coil 29 of the electronic throttle driving device 10 are connected in series, one end of which is connected to the ground, and the other end of which is connected to the electronic controller 33 via a cable 34. It is connected to the electromagnetic clutch drive circuit 33d.

The electronic controller 33 has a microcomputer 33a and a self-holding relay circuit 33c in addition to the motor drive circuit 33b and the electromagnetic clutch drive circuit 33d. The microcomputer 33a includes the accelerator sensor 12a, the throttle sensor 12b, the vehicle speed sensor, and the like. 35,
A cancel switch 37 and a set switch 39 are connected, and a brake limit switch 41 is connected to the self-holding relay circuit 33c.
An accelerator limit switch 43 is connected between 3c and the motor drive circuit 33b.

The accelerator sensor 12a is an accelerator opening sensor (double system), detects the accelerator opening ACC of the accelerator pedal 31 based on the output voltage of the potentiometer, and supplies the detected accelerator opening ACC to the microcomputer 33a. The throttle sensor 12b is a throttle opening sensor, detects the throttle opening TVO of the throttle valve 1 based on the output voltage of the potentiometer, and supplies it to the microcomputer 33a. The vehicle speed sensor 35 supplies a pulse signal having a frequency proportional to the vehicle speed to the microcomputer 33a by an electromagnetic pickup or the like provided on the transmission output shaft.

A set switch 39 is an ASCD set switch for indicating the start of automatic constant speed traveling control (ASCD), and the cancel switch 37 is an automatic constant speed traveling control (ACD).
This is an ASCD cancel switch for canceling SCD). The brake limit switch 41 is a switch that is closed and turned on only when the brake is not operated, and the accelerator limit switch 43 is a switch that is opened and turned off only when the accelerator is not operated.

The microcomputer 33a is a normal one-chip microcomputer and includes a CPU, a RAM, a ROM, a digital port, an A / D port, various timers, etc., and outputs a CLUTCH signal for instructing energization of an electromagnetic clutch when the system is normal. DIR that calculates the target throttle opening based on the output signals of various sensors and the switch signal, and indicates the forward / reverse direction of the DC motor 7 so that the actual throttle opening matches this target value.
And a DUTY signal for instructing the drive current of the DC motor 7. When the system fails, the DC motor 7
A signal instructing to cut off the drive current and the clutch drive current is output, and control is performed to shift from throttle control by the DC motor 7 to direct throttle control by the accelerator pedal 31.

The motor drive circuit 33b includes a microcomputer 33a
The on / off control of the power transistor in the output stage is performed based on the DUTY signal and the DIR signal from the CPU to control the drive current and current direction of the DC motor 7. The self-holding relay circuit 33c turns on when the set switch 39 is pressed, and thereafter keeps on until the cancel switch 37 is pressed, the brake is operated, or the ignition switch is turned off. The electromagnetic clutch drive circuit 33d controls on / off of the power transistor based on the CLUTCH signal from the microcomputer 33a, and controls the first electromagnetic clutch coil 19 and the second electromagnetic clutch coil 29.

Next, the operation of the electronic throttle driving device configured as described above will be described with reference to flowcharts shown in FIGS. FIGS. 3 and 4 are linked by jump symbols to show a continuous action.

First, it is checked whether or not the ignition switch of the vehicle is on (step P1). When the throttle valve 1 is turned on, whether the throttle valve 1 is controlled by the DC motor 7 or the accelerator pedal 31 is determined by a signal from the engine speed, the intake air amount, the accelerator opening, and other sensors and switches of the vehicle. (Step P2). When the control is performed by the DC motor 7, the process proceeds to step P3, where the system is diagnosed based on signals from the sensors and switches, and the presence or absence of a failure is confirmed (step P4).

If the ignition switch is not turned on in the check in step P1, or if the control is not performed by the DC motor 7 in the check in step P2, the process proceeds to step P15, where the drive current and the rotation direction of the DC motor 7 are instructed. DIR signal and D
The UTY signal is initialized to 0, then the CLUTCH signal indicating the drive current of the first electromagnetic clutch coil 19 and the second electromagnetic clutch coil 29 is initialized to 0 (step P16), and the DC motor 7 and the throttle valve 1 are further initialized. Is set to 0 (step P17), indicating the state in which is linked to (step P17), and the process returns to the initial processing.

The result of the system diagnosis in step P3 is determined in step P4 as to whether it is normal or not.
Proceeding to step P5, if the timed timer is in operation, the timer is released, and then the accelerator opening ACC, the throttle opening TVO and the vehicle speed VSP are read and calculated from the output signals of the accelerator sensor 12a, the throttle sensor 12b and the vehicle speed sensor 35. (Steps P6 and P7). Then, the process proceeds to Step P8.

In step P8, the automatic cruise control (A
SCD) or accelerator-by-wire control is determined from the value of the flag Fmode1. When the flag Fmode1 is 1, the process proceeds to Step P9, and when the flag Fmode1 is 0, the process proceeds to Step P19.

In step P9, it is determined whether or not the set switch 39 for instructing the start of the ASCD control has been turned on. If it is on, the process proceeds to step P12, and if it is off, the process proceeds to step P24.

In step P24, a target throttle opening TVOR is calculated from the accelerator opening ACC based on a predetermined accelerator opening-throttle opening correspondence map in consideration of the engine and vehicle characteristics of the vehicle (accelerator-by-wire). Control operation). Then, proceeding to step P25, using a control method such as PID control, DUTY instructing the motor drive current and D instructing the rotation direction of the motor based on the throttle opening deviation (TVOR-TVO).
Calculate IR. Next, a flag Fmode2 indicating that the DC motor 7 and the throttle valve 1 are connected is set to 1
Is checked (step P26). When the flag Fmode2 is 0, the process proceeds to Step P28,
The CPU outputs 1 to the CLUTCH signal for instructing the drive current of the first electromagnetic clutch coil 19 and the second electromagnetic clutch coil 29, sets the flag Fmode2 to 1, and returns to step P
Proceed to 27. At the check in step P26, the flag Fmo
Even if de2 is 1, the process proceeds to step P27, where the DUTY and DIR are stored in a predetermined I / O register of the microcomputer 33a.
The information is written, a 1-bit signal indicating the rotation direction of the DC motor 7 of the PWM signal is output, and the process returns to the initial processing.

In the check of step 9, the ASCD
If the set switch 39 for instructing the start of control is ON, the process proceeds to step P12, where the flag Fmode1 is set to 0, and then the current vehicle speed VSPO is set to the target vehicle speed VSPR.
(Step P13), and the vehicle speed deviation (VSPR−VSP) is determined using a known control method such as PID control.
DU for instructing the drive current of DC motor 7 based on O)
TY and DIR indicating the rotation direction of the DC motor 7 are calculated (ASCD control calculation) (step P14), and then the process proceeds to step P25 and thereafter, where the same processing as described above is performed.

Further, in the check in step P8,
If the flag Fmode1 is 0, the process proceeds to step P19 to determine whether or not the cancel switch 37 for instructing release of the ASCD control has been turned on. If not, whether or not the brake has been operated from the brake switch (Step P20), and when the brake is not operated, the process proceeds to Step P14, and the same processing as described above is performed. If the cancel switch 37 is turned on in step P19 and if the brake is operated in step P20, the process proceeds to step P21, where the flag Fmode1 is set to 1, and the process proceeds to step P2.
Proceeding to step No. 4, the calculation of the accelerator-by-wire control described above is performed.

If the result of the system diagnosis in step P4 is not normal, the routine proceeds to step P10, where it is determined whether or not the timed timer is operating. If it is not in operation, the timer is activated and the above-described step P1 is performed.
The process proceeds to step P5 and thereafter. If the timer is operating, it is determined whether or not the time limit of the time timer has elapsed. If the time has not elapsed, the process proceeds to step P15 and thereafter. Then, a warning lamp indicating an abnormality of the electronic throttle driving device is turned on (step P22), and it is checked whether the ignition switch is on (step P22).
23). If the ignition switch is on, the process returns to step P22 to continue the lighting process of the warning lamp. If the ignition switch is off, the process returns to the initial process.

As described above, the electronic throttle driving device according to the embodiment of the present invention shown in FIGS.
In the embodiment shown in FIG. 1, the first electromagnetic clutch coil 19 and the second electromagnetic clutch coil 29 are connected in series, and the value of the inductance of the first electromagnetic clutch coil 19 is changed to the second electromagnetic clutch coil. It is set smaller than the value of the inductance of the clutch coil 29. As a result, when the second electromagnetic clutch 5 is operated by the second electromagnetic clutch coil 29 to electronically control the throttle valve 1 via the DC motor 7,
When an abnormal state occurs in the motor 7 or the like, in order to cope with the abnormal state, the power supply to the second electromagnetic clutch coil 29 is stopped to disconnect the second electromagnetic clutch 5, and at the same time, the first electromagnetic clutch coil 19 When the current supply to the first electromagnetic clutch 3 is stopped and the first electromagnetic clutch 3 is to be connected, the inductance of the second electromagnetic clutch coil 29 is large and the inductance of the first electromagnetic clutch coil 19 is small.
Since the connection of the first electromagnetic clutch 3 is performed earlier than the disconnection of the second electromagnetic clutch 5, the accelerator and the DC motor can be maintained in the connected state for a predetermined time, and the throttle valve 1 is instantaneously turned on. Accelerator pedal 31
As a result, the throttle valve 1 is momentarily closed by the bias of the return spring 9 for the throttle valve, and the engine changes unexpectedly. Can be avoided.

In another embodiment of the present invention, the first clutch for biasing the first electromagnetic clutch 3 is used instead of the inductance of the first and second electromagnetic clutch coils 19 and 29 described above. The spring constant K ₁ of the spring 17 is set to be larger than the spring constant K ₂ of the second clutch urging spring 27 of the second electromagnetic clutch 5. By setting in this manner, similarly to the above, when the second electromagnetic clutch 5 is operated and the throttle valve 1 is electronically controlled via the DC motor 7, an abnormal state of the DC motor 7 or the like occurs. In order to cope with this, the power supply to the second electromagnetic clutch coil 29 is stopped to disconnect the second electromagnetic clutch 5, and at the same time, the power supply to the first electromagnetic clutch coil 19 is stopped. Even when the first electromagnetic clutch 3 is to be connected, the spring constant K ₁ of the first clutch urging spring 17 of the _first electromagnetic clutch 3 is set to the second clutch urging force of the second electromagnetic clutch 5. is greater than the spring constant K ₂ of the spring 27, since the connecting of the first electromagnetic clutch 3 is performed earlier than the disengagement of the second electromagnetic clutch 5, the coercive in the connected state and a predetermined time accelerator and DC motor And the throttle valve 1 instantaneously moves the accelerator pedal 3
1 and the DC motor 7 are not connected, and as a result, the throttle valve 1
Can be momentarily closed by the bias of the return spring 9 for the throttle valve to prevent the engine from changing unexpectedly.

[0032]

As described above, according to the present invention,
The timing at which the second electromagnetic clutch is switched from the engaged state to the released state is delayed from the timing at which the first electromagnetic clutch is switched from the released state to the engaged state. The first electromagnetic clutch is securely connected, so that the throttle valve is not connected to the accelerator pedal or the motor, and the throttle valve opening does not change unnecessarily, thereby improving the marketability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of an electronic throttle driving device according to an embodiment of the present invention.

FIG. 2 is a system configuration diagram using the electronic throttle drive device shown in FIG.

FIG. 3 is a flowchart showing an operation of the electronic throttle drive device shown in FIGS.

FIG. 4 is a flowchart showing the operation of the electronic throttle drive device shown in FIGS.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle valve 3 1st electromagnetic clutch 5 2nd electromagnetic clutch 7 DC motor 9 Throttle valve return spring 17 1st clutch biasing spring 19 1st electromagnetic clutch coil 27 2nd clutch biasing spring 29 Second electromagnetic clutch coil

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02D 41/14 320 F02D 41/14 320D 41/20 310 41/20 310C 41/22 310 41/22 310E (58) Fields surveyed (Int.Cl. ⁶ , DB name) F02D 9/02 351 F02D 11/10 F02D 29/02 301 F02D 41/14 320 F02D 41/20 310 F02D 41/22 310

Claims (3)

(57) [Claims] 1. A throttle valve installed in a throttle body and an accelerator lever interlocked with an accelerator pedal, which are arranged between the throttle valve and an accelerator pedal by an urging force of a spring when the electromagnetic coil is de-energized. A first electromagnetic clutch which is opened by a magnetic force of the electromagnetic coil when the electromagnetic coil is energized; an electromagnetic coil electrically connected in series with the electromagnetic coil of the first electromagnetic clutch; And a second electromagnetic clutch which is connected by the magnetic force of the electromagnetic coil when the electromagnetic coil is energized, and is opened by the biasing force of a spring when the electromagnetic coil is not energized; Control means for controlling energization and de-energization of the second electromagnetic clutch and rotation of the motor; An electronic throttle drive device comprising: delay means for delaying the timing of switching the electromagnetic clutch from the engaged state to the released state from the timing of switching the first electromagnetic clutch from the released state to the engaged state. 2. The electronic throttle drive device according to claim 1, wherein the number of turns of the electromagnetic coil of the first electromagnetic clutch is smaller than the number of turns of the electromagnetic coil of the second electromagnetic clutch. 3. The electronic system according to claim 1, wherein a spring constant of a spring for urging the first electromagnetic clutch is larger than a spring constant of a spring for urging the second electromagnetic clutch. Throttle drive.