JPS61291224A - Automatic car-speed controller - Google Patents

Abstract

PURPOSE:To improve safety and reliability in anomaly by cutting off an electromagnetic clutch set between a throttle valve and a motor for driving said throttle valve when it is judged that the terminal voltage of said motor is abnormal. CONSTITUTION:A car speed sensor 1 for outputting the operation data proportional to the actual car speed is installed, and said operation data is input into a control means 11. When said control means 11 receives the cruise instruction signal generated by the operation of a command switch 2, the operation data is memorized into a memory means 3. An actuator 7 is controlled through a motor driving circuit 8 in correspondence with the difference between the actual car speed and the memorized car speed, and the opening degree of a throttle valve 6 is adjusted. At this time, the normality is judged by detecting tee terminal voltage of the driving motor 5 for the actuator 7 by an anomaly judging means 10, and when anomaly is judged, the electric conduction to an electromagnetic clutch 4 is cut off by a relay 9.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to an automatic vehicle speed control device used to automatically control the traveling speed of a vehicle to a certain set speed. be.

(Prior Art) This type of automatic vehicle speed control device has heretofore been of various configurations, and for example, one has the configuration shown in FIG. 4. That is, a vehicle speed sensor 301 that outputs operational data proportional to the actual vehicle speed, a command switch 302 that outputs a cruise command signal, and a vehicle speed memory that stores operational data of the vehicle speed sensor 301 in response to the operation of the command switch 302. an actuator 307 that includes means 303 and a drive motor 306 that drives a throttle valve 304 of the vehicle via an electromagnetic clutch 305;
, a motor drive circuit 308 that rotates the drive motor 306 of the actuator 307 in forward and reverse directions, a relay 309 that supplies and cuts off power to the electromagnetic clutch 305 and the motor drive circuit 308 of the actuator 307, and a relay 309 that controls the actual vehicle speed and the memorized vehicle speed. The actuator 3 corresponds to the difference between
07.

As described above, this vehicle speed control device uses an actuator 307 that is equipped with a drive motor 306 to drive the throttle valve 304 of the vehicle, and uses an actuator that utilizes the engine's intake negative pressure. This makes it suitable for use in turbocharged engines, small engines, etc. where negative pressure cannot be used.

(Problems to be Solved by the Invention) However, in such a conventional vehicle speed automatic control device, a motor drive circuit 308 is used to drive the drive motor 306 in forward and reverse rotations according to commands from the control means 310. , this motor drive circuit 30B uses a transistor because its internal operating voltage is low and the circuit itself can be miniaturized, but this transistor is sensitive to excessive voltage and current, and excessive voltage If this condition occurs during automatic vehicle speed control, there is no way for the driver to detect the abnormality and cancel the system without stopping the drive motor. There is a problem in that the throttle valve 306 is fixed in the same position and the throttle valve 304 cannot be returned to the neutral position.

Therefore, the present invention has been made by focusing on the above-mentioned conventional problems, and even if the transistor in the motor drive circuit is destroyed by excessive voltage or current, the system itself will not operate the motor drive circuit during automatic vehicle speed control. It is an object of the present invention to provide a vehicle speed fluctuation control device that can cancel the system if it is determined to be abnormal by detecting whether or not the transistor in the vehicle is normal.

[Configuration of the Invention] (Means for Solving the Problems) In order to achieve the above object, the configuration of the present invention will be explained using the functional block diagram shown in FIG. 1. A vehicle speed sensor 1 that outputs a cruise command signal, a command switch 2 that outputs a cruise command signal, a vehicle speed storage means 3 that stores operational data of the vehicle speed sensor 1 in response to the operation of the command switch 2, and an electromagnetic clutch 4. A motor-driven actuator 7 that drives a throttle valve 6 with a drive motor 5, a relay 9 that cuts off the power supply to the actuator 7 and the motor drive circuit 8, and a relay 9 that controls the throttle valve 6 during automatic vehicle speed control. an abnormality determination means 10 that detects the terminal voltage of the drive motor 5 to determine whether it is normal; and an abnormality determination means 10 that sends a command to the motor drive circuit 8 in response to the difference between the actual vehicle speed and the stored vehicle speed and determines the abnormality. control means 11 for cutting off power supply to the actuator 7 when the means 10 determines that there is an abnormality;
It is equipped with the following.

(Function) During automatic vehicle speed control based on commands from the control means 11, the terminal voltage of the drive motor 5 is always detected by the abnormality determining means 10, and if there is an abnormality in the terminal voltage detected by the abnormality determining means 10, the motor It is determined that there is an abnormality in the transistor in the drive circuit 8, and a signal thereof is sent to the control means 11, and the relay 9 cuts off the power to the electromagnetic clutch 4 to release the interlocking state between the drive motor 7 and the throttle valve 6. This returns the throttle valve 6 to the neutral position and cancels the system.

(Example) Hereinafter, the present invention will be explained based on the drawings.

FIGS. 2 and 3 are diagrams showing an embodiment of the present invention.

In Fig. 2, 21 is a vehicle speed sensor that outputs pulses that are operation data proportional to the actual vehicle speed, and 22 is a command switch that outputs a cruise command signal.This command switch 22 includes a set switch, a resume switch, etc. included. The outputs from the vehicle speed sensor 21 and the command switch 22 are input to the microcomputer 26 in the controller 23 via interfaces 24 and 25, respectively, in the controller 23. Inside the microcomputer 26, there is a vehicle speed storage means for storing the vehicle speed at the time of operation from the vehicle speed sensor 21 in response to the operation of the command switch 22, and a drive motor 28 for the actuator 27, which will be described later, during adjustment operation during automatic vehicle speed control. an abnormality determining means for determining whether or not a motor drive circuit 29 which detects the terminal voltage of and outputs a forward/reverse rotation signal to the drive motor 28 is working normally; and a vehicle speed stored in the vehicle speed storage means and a vehicle speed sensor. 21 and controls the vehicle speed based on the difference, and cancels the system when the abnormality determining means determines that the motor drive circuit 29 is abnormal.

Further, 27 is a motor-driven 7 actuator that drives the throttle valve 30 of the vehicle, and this actuator 27 is equipped with a drive motor 28 and an electromagnetic clutch 31, and this electromagnetic clutch 31 According to the command, a clutch portion (not shown) is engaged/disconnected, and the rotation of the drive motor 28 is transmitted to the throttle valve 30 via a deceleration mechanism (not shown). The electromagnetic clutch 31 has an output shaft (not shown) connected to the throttle valve 30 via an output transmission mechanism (not shown), such as an output link.

Further, the motor drive circuit 2 includes a controller 23.
The drive motor 28 of the actuator 27 is controlled to rotate forward or backward according to the output of the microcomputer 26.The circuit configuration of the motor drive circuit 22 is such that one terminal of the drive motor 28 is connected to the power supply. A transistor Trl connected to the positive electrode of 32, and this transistor Tr
a motor forward rotation switching unit 33 that turns on and off the motor 1 in response to a motor forward rotation signal output from the output boat OA of the microcomputer 26; and a drive motor 28 in response to a motor forward rotation signal output from the output boat OA.
A transistor Tr2 connects the other terminal of the drive motor 28 to the negative electrode of the power supply 32, and connects the other terminal of the drive motor 28 to the power supply 32.
a motor reverse rotation switching unit 34 that turns on and off the transistor Tr3 in response to a motor reverse rotation signal output from the output port OB of the microcomputer 26; A transistor Tr4 is provided to connect one terminal of the drive motor 28 to the negative terminal of the power supply 32 in response to a motor reverse rotation signal output from the microcomputer 26. As a result, the transistors Tri and Tr2 are turned on, and the drive motor 28 rotates in the forward direction, that is, the throttle valve 30 is rotated toward the speed increasing side. In addition, the motor reverse rotation signal output from the output port OB of the microcomputer 26 causes the transistors Tr3 and Tr4 to
is turned on, and the drive motor 28 rotates in the reverse direction, that is, rotates the throttle valve 30 toward the deceleration side. In addition,
Both terminals of the drive motor 28 are connected to input ports IA and IB of the microcomputer 26,
An abnormality determining means within the microcomputer 26 detects the voltage between both terminals of the drive motor 28.

Reference numeral 1.35 is an actuator switching unit located in the controller 23 that turns on/off the power supply to the motor drive circuit 2 and the actuator 27 in accordance with the output from the microcomputer 26;
At this time, the relay coil 36a and the relay switch 36 are turned on and off as the transistor Tr5 of the actuator switching section 35 is turned on and off.
This is done via a relay 36 consisting of b.

Further, 37 is a brake switch, and 38 is a brake lamp, through which a signal for canceling the system when the brake is operated is inputted to the microcomputer 26 via an interface 32 in the controller 23.

Furthermore, 40 is a constant voltage circuit, 41 is a reset circuit, 42
is a main switch for the control device, and 43 is a cruise lamp.

Next, the operation of the automatic vehicle speed control system having such a configuration will be explained, including FIG. 3.

First, to operate the automatic vehicle speed control device, turn on the main switch 42, and then turn on the vehicle speed sensor 2.
1 outputs a pulse signal which is operation data proportional to the actual vehicle speed, inputs this pulse signal to the microcomputer 26 in the controller 23, samples it within a certain period of time, and constantly outputs a pulse signal proportional to the vehicle speed to the microcomputer 26. In this state, for example, after a set signal is input to the control means in the microcomputer 26 by the set switch of the command switch 22, the cruise lamp 4 is turned on when the input signal is released.
3 lights up, the vehicle speed storage means in the microcomputer 26 stores the number of pulses corresponding to the vehicle speed at that time, and the control means in the microcomputer 26 outputs a relay drive signal to drive the transistor of the actuator switching section 35. Tr5 is turned on and relay 35 is turned on. At this time, when the relay 35 is turned on, the electromagnetic clutch 31 and the motor drive circuit 22 are energized, and in this state, the control means of the microcomputer 26 controls the motor according to the number of pulses stored in the vehicle speed storage means. The forward rotation signal is output, the motor forward rotation switching section 33 of the motor drive circuit 22 and the transistor Tr2 are turned on, and the motor forward rotation switching section 33 is turned on, so that the transistor T is turned on.
When rr is turned on and the drive motor 28 of the 7-cut unit 27 is rotated in the forward direction, the electromagnetic clutch 31
The throttle valve 30 is held at a predetermined position via an output transmission mechanism (not shown). After this, even if the accelerator pedal is released, the throttle valve 30 is held at a predetermined position, so that the vehicle can run at a constant speed. In this automatic vehicle speed control, in order to maintain the set vehicle speed, the control means of the microcomputer 26 uses the number of pulses proportional to the actual vehicle speed of the vehicle speed sensor 21 and the pulses stored in the vehicle speed storage means of the microcomputer 26. Compare with the number (memory vehicle speed),
One of the motor normal/reverse rotation signals corresponding to the difference is output to the motor drive circuit 29, and the drive motor 28 is operated to keep the vehicle speed constant.

At this time, the abnormality determining means in the microcomputer 26 detects the voltage between both terminals of the drive motor 28.

That is, when automatic vehicle speed control is started, the abnormality determination program shown in FIG. 3 is also in operation, and in step 101, it is determined whether automatic vehicle speed control is being performed, and if automatic vehicle speed control is not being performed (NO). In this case, the voltage at both terminals of the drive motor 28 cannot be detected, and there is no need to detect the voltage at both terminals of the drive motor 28. Therefore, after executing another program in step 102, the process returns to step 101.

Further, in step 101, if vehicle speed fluctuation control is being performed (YES), it is determined in step 103 whether or not there is a control pulse. That is, it is determined whether the control means in the microcomputer 26 is outputting a motor normal/reverse rotation signal, and if either one of the motor normal/reverse rotation signals is being output (
If YES), it is determined in step 104 whether the signal is a pull signal or not. That is, if the motor reverse rotation signal is not output from the control means of the microcomputer (No), in step 105, the terminal voltage of the drive motor 28 at that time is in the OFF state on the pull side and the ON state on the return side. Determine whether or not. That is, the terminal voltage of the drive motor 28 is detected to determine whether or not the drive motor 28 is rotating in the forward direction. If the drive motor 28 is rotating in the forward direction (YES), A forward rotation transistor Tri in the motor drive circuit 29.

It is determined that Tr2 is working normally, and in step 106, each transistor Trl of the motor drive circuit 29,
Tr2. Tr3. The abnormality timer that operates when Tr4 has an abnormality is reset and the process returns to the first step 101.

Further, in step 105, the drive motor 28
If the drive motor 2 is not rotating in the forward direction (NO), the drive motor 2
It is determined that there is an abnormality in the forward rotation transistors Trl and Tr2 in the motor drive circuit 22 that drives the motor 8, and the abnormality timer is incremented in step 107.

Furthermore, in step 103, if the control means in the microcomputer 26 is not outputting either of the motor forward and reverse rotation signals, that is, when the vehicle speed is being automatically controlled, the control means in the microcomputer 26 is If 28 is not operating (NO),
In step 108, it is determined whether the terminal voltage of the drive motor 28 is in the OFF state for both pull and return. That is, it is determined whether or not the drive motor 28 is in a stopped state, and if the drive motor 28 is in a stopped state (
YES), each transistor Tri, Tr2, Tr3 . It is determined that Tr4 is working normally, the abnormality timer is reset in step 106, and the process returns to step 101.

Further, in step 108, the drive motor 28
If it is not in the stopped state (NO).

Each transistor Trl in the motor drive circuit 29.

Tr2. Tr3. It is determined that the transistor in either the forward or reverse rotation direction of Tr4 is out of order, and an abnormality timer is added in the next step 107.

Then, in step 104, if the control means in the microcomputer 26 outputs a motor reverse rotation signal (YES), in step 109, the terminal voltage of the drive motor 28 at that time is on the pull side. In the ON state, it is determined whether the return side is in the OFF state.

That is, it is determined whether or not the drive motor 28 is rotating in the reverse direction. If the drive motor 28 is rotating in the reverse direction (YES), each of the transistors Trl and Tr2 in the motor drive circuit 29 Tr3. It is determined that Tr4 is working normally, the abnormality timer is reset in step 106, and the process returns to step 101.

Further, in step 109, the drive motor 28
is not rotating in the reverse direction (NO), each transistor Trl, Tr2 . Tr3. T
r4(7) including reverse rotation transistor Tr3. It is determined that Tr4 is out of order, and an abnormality timer is added in step 107.

Then, in each step 105, 108, 109, an abnormality is determined, and the abnormality timer added in step 107 is changed to
It is determined whether a certain time CX) or more has been reached. That is, in each step 105, 108, 109, each transistor Tri in the motor drive circuit 29 at that time
.

Even if it is determined that there is an abnormality in any one of Tr2, Tr3, and Tr4, the control means and abnormality determination means in the microcomputer 26 may malfunction due to noise (ignition noise, radio wave interference, etc.). In step 110, if the abnormal state continues for a certain period of time (X) or more, a failure is determined.
If the abnormality timer does not reach a certain time (X) or more (N
For o), return to step 101.

Further, in the step 110, if the abnormality timer reaches a certain time (X) or more (YES), the system is canceled in the next step 111. That is, this is because the terminal voltage of the drive motor 28 is in an abnormal state for a certain period of time (X) or more in step 110.

The abnormality determination means in the microcomputer 26 includes each transistor Tri in the motor drive circuit 29.

Tr2. Tr3. When it is determined that any one of the Tr 4 is out of order, the control means in the microcomputer 26 cuts off the power supply to the actuator switching section 35 and cuts off the power supply to the relay 36, so that the actuator 27 The power supply to the electromagnetic clutch 31 is cut off, and the clutch portion (not shown) of the electromagnetic clutch 31 is disengaged. Therefore, the throttle valve 3o
By disengaging the actuator 27, the system returns to the neutral position and the system is casoscelled.

As a result, the motor-driven actuator 27 is controlled by each transistor T in the motor drive circuit 22 because the abnormality determination means in the microcomputer 26 detects the voltage across both terminals of the drive motor 28 during automatic vehicle speed control.
r 1 + T r 2 ! Tr3. Positive among Tr4
Even if one of the transistors for one direction of reverse rotation were to fail, each transistor Trl, Tr2 . T
It is possible to detect an abnormality in r3°Tr4, and the system can be canceled based on this detection result.
System safety can be ensured.

[Effects of the Invention] As described above, according to the present invention, a vehicle speed sensor that outputs operational data proportional to the actual vehicle speed, a command switch 9 that outputs a cruise command signal, and a command switch 9 that responds to the operation of the command switch are provided. a motor-driven actuator that drives a throttle valve with a drive motor via an electromagnetic clutch; and a motor-driven actuator that supplies and cuts off power to the actuator and motor drive circuit. a relay, an abnormality determining means for detecting the terminal voltage of the drive motor during adjustment of the throttle valve during automatic vehicle speed control and determining whether it is normal; By providing a control means that sends a command to the motor drive circuit and cuts off the power supply to the actuator when the abnormality determining means determines that there is an abnormality, the transistor constituting the motor drive circuit can be operated during automatic vehicle speed control. Even if a failure occurs, the abnormality determination means in the vehicle speed control center detects the terminal voltage of the drive motor. The excellent effect of improving the safety and reliability of the system can be obtained.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a functional block diagram showing a configuration according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a circuit configuration of an automatic vehicle speed control device according to an embodiment of the present invention, and FIG. The figure is a flowchart showing an abnormality determination routine performed by a microcomputer, and FIG. 4 is a functional block diagram showing the configuration of a conventional automatic vehicle speed control device. DESCRIPTION OF SYMBOLS 1... Vehicle speed sensor, 2... Command switch, 3... Vehicle speed storage means, 4... Electromagnetic clutch, 5... Drive motor, 6... Throttle valve, 7... Actuator, 8... Motor drive circuit, 9... Relay, 10... Abnormality determination means, 11... Control means. Patent applicant Patent attorney representing Jidosha Electric Industry Co., Ltd.
Yutaka Koshio Figure 1 6... Throttle valve.

Claims (1)

[Claims] (1) a vehicle speed sensor that outputs operational data proportional to the actual vehicle speed, a command switch that outputs a cruise command signal, and a vehicle speed storage means that stores operational data of the vehicle speed sensor in response to operation of the command switch; A motor-driven actuator that drives the throttle valve with a drive motor via an electromagnetic clutch, a relay that supplies and cuts off power to the actuator and the motor drive circuit, and a motor-driven actuator that operates to adjust the throttle valve during automatic vehicle speed control. an abnormality determining means for detecting a terminal voltage of the motor to determine whether the motor is normal; and an abnormality determining means for sending a command to the motor drive circuit in response to the difference between the actual vehicle speed and the stored vehicle speed, and determining that the abnormality is abnormal by the abnormality determining means. An automatic vehicle speed control device comprising: control means for cutting off power supply to the actuator when the actuator is activated.