JPH0565726U - Accelerator switch failure detection device - Google Patents

Abstract

(57) [Abstract] [Purpose] Even by using a normally-off switch that has been used conventionally, by observing that the engine speed is rising and the accelerator switch mode (whether the accelerator switch is on or not) We propose an accelerator switch failure detection device that can easily determine the failure of the accelerator switch. [Structure] Engine speed sensor 1 and accelerator switch 2
The wheel speed sensor 4 and the signals from these sensors actuate the solenoid valve 8 when the vehicle is stopped to maintain the braking force, and the signals from the sensors deactivate the solenoid valve 8 when the vehicle starts. In a vehicle stop-maintaining device including an electronic control unit that releases the braking force by means of an accelerator, the engine speed remains equal to or higher than a predetermined speed and the solenoid valve 8 of the stop-maintaining device is opened when the vehicle is started, and then the accelerator switch 2 continues to operate. Is equipped with a device for turning on a warning lamp when is an off signal.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a failure detection device for a stop maintaining device that can automatically maintain the braking force of a vehicle when the vehicle is stopped by a brake operation, and more specifically, relates to an accelerator pedal. The present invention relates to a failure detection device for an accelerator switch in a stop maintaining device that automatically releases the stop maintaining state of a vehicle by stepping on the switch.

[0002]

[Prior Art]

 As is well known, when a vehicle is temporarily stopped at an intersection, etc., the vehicle stop-maintaining device keeps the brake hydraulic pressure at that time and keeps the vehicle running without the occupant operating the hand brake or stepping on the foot brake. When the vehicle is automatically stopped, the driver can automatically release the brake by detecting the state when the vehicle is started, such as stepping on the accelerator. This device is usually provided in the hydraulic circuit of the driven wheel system of the vehicle. In addition, it has recently been adopted for vehicles with an automatic transmission as an extremely effective device for preventing the creep phenomenon in vehicles with an automatic transmission.

[0003]

[Problems to be solved by the device]

 When the vehicle is started from the operating state of the stop maintaining device (that is, the vehicle is in a temporary stop state), the conventional vehicle stop maintaining device performs a vehicle start operation by turning on and off signals of a switch provided in the accelerator. In many cases, the brake signal is released by detecting the operation signal of the shift lever, or any state when the engine speed exceeds a predetermined speed or a combination of these signals. For this reason, if the accelerator switch fails, the accelerator switch will not turn on and the brake will not be released even if the accelerator pedal is pressed, or the accelerator pedal will cause the engine speed to rise above the specified speed. The situation may occur in which the brakes are not released until.

In the latter case, there is a danger that the brake will be suddenly released and the vehicle will suddenly start when the engine speed exceeds a predetermined speed, leading to a serious accident. In order to deal with such a situation, it suffices to detect a failure of the accelerator switch in advance, but in the conventional vehicle stop maintaining device, if the accelerator switch does not turn on, it does not turn on because the accelerator is not stepped on enough. It was difficult to electrically determine whether the switch did not turn on due to the failure of the accelerator switch.

Therefore, the inventor of the present invention has found that the engine speed is increasing and the accelerator switch mode (whether or not the accelerator switch is turned on) is used even in the conventional off mode switch that has been conventionally used. We propose an accelerator switch failure detection device that can easily determine the failure of the accelerator switch by looking at it, and try to solve the above problems.

[0006]

[Means for Solving the Problems]

 Therefore, according to the present invention, an engine speed sensor 1, an accelerator switch 2, a wheel speed sensor 4, and a signal from each of these sensors actuate an electromagnetic valve 8 to stop the vehicle when the vehicle is stopped, and to hold the braking force. In a vehicle stop / maintenance system, the electronic control unit 10 has a predetermined engine speed when the vehicle starts, and the electronic control unit 10 releases the braking force by releasing the operation of the solenoid valve 8 according to the signals from the respective sensors. The present invention is characterized in that it is provided with a means for operating a warning device when the accelerator switch 2 is an off signal after opening the solenoid valve 8 at a number of revolutions or more, and this is a means for solving the problem. It is a thing.

[0007]

[Action]

 (When the vehicle is stopped) When the brake pedal is stepped on at an intersection or the like while the vehicle is running and the hydraulic pressure from the master cylinder is supplied to the brake cylinder, the vehicle stops. When the speed determination means 14 determines that the wheel speed has become zero based on the signal from the speed sensor 4, the signal a at this time is input to the S terminal of the flip-flop 19 to switch the solenoid valve 8 to the A position in FIG. Hold the power.

(When the Vehicle Starts) (b) When the Accelerator Switch is Not Faulted When the vehicle starts and the accelerator is stepped on, the accelerator switch 2 is turned on. This signal is input to the OR circuit 17, and the output b from the OR circuit is input to the R terminal of the flip-flop 19 to switch the solenoid valve 8 to the B position in FIG. 1 and release the braking force. In this way, the vehicle that has been temporarily stopped at an intersection or the like will automatically release the braking force only by stepping on the accelerator, and the vehicle can start smoothly.

In addition to releasing the braking force, when the engine speed becomes higher than a constant speed (a speed slightly higher than idling), the braking force is released at zero wheel speed. It is also done when it is gone. That is, when the engine speed becomes higher than the constant speed, the signal of the engine speed determination means 15 is input to the OR circuit 17, and the output b from the OR circuit 17 is input to the R terminal of the flip-flop 19 to cause electromagnetic interference. The valve 8 is switched to the B position in FIG. 1 to release the braking force. When the wheel speed is not zero, a signal is input to the OR circuit 17 via the inverter 16, and the output b from the OR circuit 17 is input to the R terminal of the flip-flop 19, and the solenoid valve 8 is turned on as described above. Switch to position B in Fig. 1 to release the braking force. As described above, when the vehicle starts, it is automatically detected that the accelerator switch is turned on, the engine speed becomes a certain speed or more, or the wheel speed becomes non-zero. As a result, the braking force is released and the vehicle can start smoothly.

(B) When the accelerator switch is out of order When the vehicle starts, even if the accelerator is stepped on, the accelerator switch 2 is out of order and the accelerator switch is not turned on, so the brake is not released. However, the driver is warned when a failure of the accelerator switch is detected as follows. Even if the accelerator is stepped on to start, the accelerator switch does not turn on. However, the engine speed increases because the accelerator is depressed. When the engine speed determining means 15 determines that the engine speed at this time is higher than a constant speed (a speed slightly higher than idling), a signal is input from the engine speed determining means 15 to the OR circuit 17 and further ORed. The output from the circuit 17 is input to the R terminal of the flip-flop 19 to switch the solenoid valve 8 to the B position in FIG. 1 to release the braking force. At the same time, the off timer 20 outputs an on signal only for a certain time T as shown in FIG. 3, and this signal is input to the AND circuit 21.

Further, the exclusive logic circuit 18 receives a signal from the engine speed judging means 15, but does not receive a signal from the accelerator switch 2 because the accelerator switch is out of order. Therefore, the exclusive logic circuit 18 outputs the signal c, which is input to the AND circuit 21. As a result, the ON signal of the OFF timer 20 and the signal from the exclusive logic circuit 18 are input to the AND circuit 21, so that a signal is output, whereby the latch circuit 22 operates and the warning lamp 9 lights up. Alert the driver of a malfunction of the accelerator switch.

[0012]

【Example】

 An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an overall configuration of a vehicle stop / maintenance device as an embodiment of the present invention, and FIG. 2 is an accelerator switch failure of FIG. FIG. 3 is a logic diagram as the detecting means, and FIG.

In FIG. 1, 1 is an engine speed sensor, 2 is an accelerator switch provided on an accelerator pedal 3, 4 is a speed sensor provided on a rear wheel 7, and signals from these sensors are electronically controlled. It is input to the device (ECU) 10. The electronic control unit 10 outputs a signal for switching the solenoid valve 8 described later to the A and B positions based on the signals from the respective sensors. The solenoid valve 8 is provided in a pipe line that connects the master cylinder 11 that generates hydraulic pressure when the brake pedal 12 is depressed and the brake cylinder of the front wheel 6 that is a driven wheel, and outputs a signal from the electronic control unit when the brake is operating. When comes to, it switches to the A position and holds the braking force in that state. Reference numeral 9 is a warning lamp as a warning device, which is turned on when the electronic control unit 10 detects a failure of the accelerator switch. When the warning lamp 9 lights up, the driver can recognize that the accelerator switch is out of order. Instead of the warning lamp 9, a warning device using a buzzer sound or other various phenomena may be used.

During traveling, when the brake pedal is depressed and the hydraulic pressure from the master cylinder is supplied to the brake cylinder, the vehicle stops. At the same time, the speed sensor 4 outputs a signal that the wheel speed is zero. Based on the signal from the speed sensor 4, the electronic control unit 10 determines that the vehicle is in a stopped state by a logic circuit described later, and switches the solenoid valve 8 to the A position to hold the braking force. In this way, the braking force is automatically maintained every time the vehicle temporarily stops at an intersection or the like, and the driver is relieved of the trouble of operating the handbrake one by one as in the conventional case.

Further, when the vehicle starts, based on any one of the ON signal of the accelerator switch 2, a signal that the engine speed is equal to or higher than a certain speed, or a signal that the wheel speed is not zero. The electronic control unit 10 switches the solenoid valve 8 to the B position to release the braking force. In this way, when the vehicle starts, the braking force is automatically released and the vehicle can start smoothly. Further, when the accelerator switch 2 is out of order when the vehicle starts, the failure is detected by the logic circuit, which will be described later, provided in the electronic control unit 10, the warning lamp 9 is turned on, and the driver is informed of the accelerator switch 2. It warns that there is a failure. As a result, it is possible to prevent the vehicle from suddenly starting due to excessive depression of the accelerator.

A logic circuit (accelerator switch failure detection means) for detecting a failure of the accelerator switch will be described with reference to FIG. Reference numeral 14 in the figure is a zero speed judging means for judging whether or not the wheel speed is zero on the basis of the signal from the speed sensor 4. The signal outputted from this means is sent to the S terminal of the flip-flop 19 and the inverter 16. Further, the output from the inverter 16 is input to the OR circuit 17. Reference numeral 15 is an engine speed determining means for determining whether or not the engine speed is a certain speed or higher (whether or not the engine speed is slightly higher than idling). The signal output from this is OR. It is input to the circuit 17 and also to the exclusive logic circuit 18 which detects a failure of the accelerator switch.

A signal from the accelerator switch sensor 2 is also input to the OR circuit 17 and the exclusive logic circuit 18. The exclusive logic circuit 18 has a function of outputting a signal when the modes of the two input signals do not match. Reference numeral 19 is a flip-flop circuit that outputs when an input signal enters the S terminal and then continues to output until an input signal arrives at the R terminal, and 20 is constant as soon as the solenoid valve 8 is turned off as shown in FIG. An off timer that outputs an on signal only at time T, 21 is an AND circuit, and 22 is a latch circuit. The latch circuit 22 is a circuit that continues to output after a short signal is input once.

The operation of the logic circuit will be described separately when the vehicle is stopped and when the vehicle is started. (When the vehicle is stopped) When the brake pedal is stepped on at an intersection or the like while the vehicle is running and the hydraulic pressure from the master cylinder is supplied to the brake cylinder, the vehicle stops. When the speed determination means 14 determines that the wheel speed has become zero based on the signal from the speed sensor 4, the signal a at this time is input to the S terminal of the flip-flop 19, and the solenoid valve 8 is switched to the A position in FIG. , Hold the braking force. In this way, the braking force is automatically maintained every time the vehicle is temporarily stopped at an intersection or the like, and the driver is relieved of the trouble of operating the hand brakes one by one as in the conventional case.

(At Vehicle Start) (b) When Accelerator Switch is Not Faulted When the vehicle starts, the accelerator switch 2 is turned on when the accelerator is stepped on. This signal is input to the OR circuit 17, and the output b from the OR circuit is input to the R terminal of the flip-flop 19 to switch the solenoid valve 8 to the B position in FIG. 1 and release the braking force. In this way, the vehicle that has been temporarily stopped at an intersection or the like will automatically release the braking force only by stepping on the accelerator, and the vehicle can start smoothly. The braking force is released when the engine speed is higher than a certain speed (a little higher than idling) in addition to turning on the accelerator switch, and when the wheel speed is no longer zero. Is also done. That is, when the engine speed becomes higher than the constant speed, the signal of the engine speed determination means 15 is input to the OR circuit 17, and the output b from the OR circuit 17 is input to the R terminal of the flip-flop 19 to cause electromagnetic interference. The valve 8 is switched to the B position in FIG. 1 to release the braking force.

When the wheel speed is not zero, a signal is input to the OR circuit 17 via the inverter 16, and the output b from the OR circuit 17 is input to the R terminal of the flip-flop 19, which is similar to the above. Then, the solenoid valve 8 is switched to the position B in FIG. 1 to release the braking force. In this way, when the vehicle starts, the braking force is automatically released even when the engine speed becomes higher than a certain speed or the wheel speed becomes zero, and the vehicle can start smoothly. ..

When the accelerator switch is not in failure, signals are input to the exclusive logic circuit 18 from the engine speed determination unit 15 and the accelerator switch 2. This circuit has two input signal modes. Since the circuit outputs only when they do not match, the signal c is not output in this state and the warning lamp does not light.

(B) When the accelerator switch is broken When the vehicle starts, when the accelerator switch 2 is broken, even if the accelerator is depressed, the accelerator switch is not turned on and the brake is not released. However, the driver is warned when a malfunction of the accelerator switch is detected as follows. Even if the accelerator is stepped on to start, the accelerator switch does not turn on. On the other hand, the engine speed increases as the accelerator is depressed. When the engine speed determination means 15 determines that the engine speed at this time becomes higher than a certain speed (a speed slightly higher than idling), the signal from the engine speed determination means 15 is input to the OR circuit 17. Further, the output from the OR circuit 17 is input to the R terminal of the flip-flop 19 and switches the solenoid valve 8 to the B position in FIG. 1 to release the braking force. At the same time, the off timer 20 outputs an on signal only for a certain time T as shown in FIG. 3, and this signal is input to the AND circuit 21.

The exclusive logic circuit 18 receives the signal from the engine speed determining means 15, but does not receive the signal from the accelerator switch 2 because the accelerator switch is out of order. As a result, the exclusive logic circuit 18 outputs a signal, which is input to the AND circuit 21. The signal from the off-timer 20 and the signal from the exclusive logic circuit 18 are input to the AND circuit 21 for a certain time T during which the off-timer 20 is outputting the on-signal, whereby the latch circuit 22 operates and the warning lamp is activated. Turn on 9. Once the warning lamp 9 is turned on, it continues to be turned on by the action of the latch circuit. In this way, the driver is warned of a malfunction of the accelerator switch when the vehicle starts, and it is possible to prevent a sudden increase in engine speed and a sudden start of the vehicle. Instead of the warning lamp 9, a warning device using a sound such as a buzzer may be used.

[0024]

[Effect of the device]

 As described above in detail, according to the present invention, even with the normally-off switch that has been conventionally used, the engine speed is increasing and the accelerator switch mode (whether the accelerator switch is on or not) is used. It is possible to easily determine the failure of the accelerator switch by looking at the (), so you can continue to depress the accelerator without knowing that the accelerator switch is malfunctioning, and only the engine speed will rise. This has an excellent effect of preventing accidents such as a sudden start of the vehicle caused by sudden release of the brake.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a vehicle stop / maintenance prevention device as an embodiment of the present invention.

FIG. 2 is a logic diagram of the accelerator switch failure detection device of FIG.

FIG. 3 is a diagram illustrating the operation of an off timer.

[Explanation of symbols]

 1 Engine Revolution Sensor 2 Accelerator Switch 3 Accelerator Pedal 4 Speed Sensor 5 Brake 8 Solenoid Valve 9 Warning Device (Warning Lamp) 10 Electronic Control Device

Claims (1)

[Scope of utility model registration request] 1. An engine speed sensor 1, an accelerator switch 2, a wheel speed sensor 4, and a signal from each of these sensors actuates a solenoid valve 8 when the vehicle is stopped to maintain a braking force and at the time of starting the vehicle. In a vehicle stop / maintenance device comprising an electronic control unit 10 for releasing the braking force by releasing the operation of the solenoid valve 8 in response to a signal from each of the sensors, the electronic control unit 10 has an engine speed of a predetermined value or more. After the solenoid valve 8 is opened, the accelerator switch 2 is provided with a means for activating a warning device when the accelerator switch 2 is an off signal.