JPH065931Y2 - Anti-skid controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is an anti-skid control that takes measures against a failure of an on-off type G sensor used in an anti-skid control device that prevents wheel lock by brake hydraulic pressure control. It relates to the device.

(Prior Art) During braking of a vehicle, the rotation state of the wheels or the propeller shaft, that is, the deceleration or slip ratio of the wheels is detected, and the brake fluid pressure is adjusted so as to maintain a certain slip ratio according to the detected value. An anti-skid control device for controlling the vehicle to obtain maximum deceleration and lateral stability of the vehicle body is already known. Here, for example, when the vehicle travels on a road surface with a high friction coefficient μ between the tire and the road surface, that is, on a paved road, anti-skid control for a high μ road is performed and the friction coefficient is When traveling on a low μ road surface, that is, on a snowy road, anti-skid control for low μ roads is performed, and the judgment of high μ roads and low μ roads is provided on the vehicle body. It is performed based on a signal from a G sensor (also referred to as an acceleration / deceleration sensor). In addition, the high μ road and low μ road based on the signal from the G sensor
To explain the road judgment, this is because when the braking force increases until the wheels tend to lock and the anti-skid control is performed, the deceleration that occurs in the vehicle is between the wheels and the road surface. It is based on being governed by the coefficient of friction. That is, the deceleration (signal from the G sensor) generated in the vehicle at the time of shifting to the anti-skid control utilizes a phenomenon that it is low on the low μ road and high on the high μ road. For example, Japanese Patent Publication No. 58-47381. And the like are known. As shown in FIG. 2, the G sensor 1 is formed in a casing 2 made of resin or metal, and is formed in the casing 2. The G sensor 1 rises in the front-rear direction of the vehicle (left-right direction in the drawing) and is located at the bottom in the approximate center. A controller composed of an inclined groove 2b having a point 2a and a microcomputer which is arranged along the inclined groove 2b in the inclined groove 2b, one base end of which serves as a plus power source 6 and the other end of which controls antiskid control. Connected to 5 respectively,
One end 3b and the other base end 3c are not in contact with each other and the inclined groove 2b
The reed switch 3 is located in the vicinity including the lowest point 2a, and the mercury ball 4 as a conductive liquid particle enclosed in the inclined groove 2b is used. During braking, the road surface resistance is high, so the deceleration increases, and the inertial force causes the mercury ball 4 to rise upward in the inclined groove 2b and reach the position shown by the phantom line. When the energized state is released, on the other hand, during braking when traveling on a low μ road, the road surface resistance is low, so the deceleration decreases and the mercury ball 4 stops at the lowest point 2a in the inclined groove 2b as indicated by the solid line. The reed switch 3 is energized. In this way, since the reed switch 3 is turned off during braking when traveling on a high μ road, the G sensor 1 does not energize the controller 5, while the reed switch 3 is turned on during braking when traveling on a low μ road. In this state, an ON signal is sent from the G sensor 1 to the controller 5, and the high μ road or the low μ road is judged based on the road surface condition signal, that is, the presence or absence of the ON signal. That is, when no output is sent from the G sensor 1 to the controller 5, the high μ road,
When the output is sent to the controller 5, it is determined to be a low μ road.

(Problems to be solved by the invention) Incidentally, the G sensor 1 may occasionally have an ON failure, which means that the mercury ball 4 is the lowest point in the inclined groove 2b.
In 2a, it means that the robot does not move without stopping as indicated by the solid line.
Is output, the controller 5 determines that the vehicle is traveling on a low μ road even when traveling on a high μ road, so that the brake hydraulic pressure is extremely relaxed when braking on a high μ road. As a result, there was a problem that the braking distance was significantly extended, which was even dangerous.

Therefore, it is an object of the present invention to provide an anti-skid brake device that can ensure stable performance even when an ON failure occurs in the G sensor and that can accurately notify the driver of the failure of the G sensor.

(Means for Solving Problems) The present invention was devised in view of the above circumstances, and includes a wheel speed sensor for detecting a wheel speed, and normally turns on and turns off when a deceleration more than a predetermined amount acts on the vehicle body. A plurality of G sensors,
The control means includes an actuator that adjusts a braking force acting on a wheel, a control unit that receives the output of each sensor and controls the operation of the actuator, and a failure notification unit that notifies a failure of the G sensor. Performs control for a low μ road when all of the plurality of G sensors are on, and executes control for a high μ road when at least one of the plurality of G sensors is off, while The anti-skid control device is characterized in that output signals of a plurality of G sensors are compared with each other, and when the signals are different from each other, the failure notification means is operated.

(Operation) According to the present invention, the control means executes the control for the low μ road when all of the plurality of G sensors are on, and the high μ road when at least one of the plurality of G sensors is off. Therefore, even if one of the plurality of G sensors fails, the control for the high μ road is executed by turning off the other G sensors during braking on the high μ road.

Therefore, the inconvenience caused by the ON failure of the G sensor can be eliminated, and the control reliability is improved.

Further, since the control means is configured to compare the output signals of the plurality of G sensors with each other and activate the failure notification means when the signals are different from each other, one of the plurality of G sensors fails. The driver can be surely notified that the vehicle is doing.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram of an anti-skid control device showing an embodiment of the present invention. As shown in FIG. 1, an on / off type G sensor 11 is composed of G sensors 11A and 11a. The G sensor 11A is formed of a casing 12 made of resin or metal, and is formed in the casing 12, rises in the front-rear direction of the vehicle (left-right direction in the drawing), and has an inclined groove 12B having a lowermost point 12A at the substantially center. And, in the inclined groove 12B, respectively arranged along the inclined groove 12B,
One base end is connected to the plus power source 6 and the other end is connected to the comparator 39 and the not circuit 20A, respectively, and one end 13B and the other base end 13C are in the non-contact state and are the lowest point in the inclined groove 12B. 12A
Reed switch 13A located near each part including
And a mercury ball 14A as a conductive liquid particle sealed in the inclined groove 12B, while the G sensor 11a is formed in the casing 12 and the casing 12, and is in the front-back direction of the vehicle. (In the left-right direction in the figure), respectively, and the inclined groove 12b having the same shape as the above-mentioned inclined groove 12B having the lowest point 12a at the substantially center, and inside the inclined groove 12b, along the inclined groove 12b, respectively. One end of the inclined groove 12b is connected to the plus power source 6 and the other end is connected to the comparator 39 and the not circuit 20a, respectively, and one end 13b and the other base end 13c are in non-contact with each other. It is composed of reed switches 13a respectively located in the vicinity including the lowest point 12a and mercury balls 14a as conductive liquid particles enclosed in the inclined grooves 12b. The comparator 39 is composed of an R-C circuit and is connected to a low-pass filter 41 for cutting off short wavelengths, the low-pass filter 41 is connected to a Schmitt trigger 42 for waveform shaping, and the Schmitt trigger 42 is connected to an NPN transistor 43. One end of the NPN transistor 43 is connected to the ground, and the other end is connected to the rectifying diode 44. The rectifying diode 44 is connected to the controller 5 and the plus power source 45 via the fail lamp 46 serving as failure notification means. . On the other hand, the not circuits 20A and 20a are connected to a nor circuit 21, and the nor circuit 21 is connected to an NPN transistor 22, respectively.
One end of the NPN transistor 22 is connected to the positive power source 23, and the other end is connected to the controller 5.

Here, one of the G sensors 11A or 11a has an ON failure, that is, one of the mercury bulbs 14A or 14a has the lowest point 12
If you get stuck in either A or 12a,
During braking during traveling on a high μ road, the G sensor that has not failed is de-energized, so that different signals are input to the comparator 39.
Is a logic "0" when the same output signal is input,
When different output signals are inputted, the logic "1" is outputted respectively, so that the comparator 39 outputs the logic "1". Then, since the logic "1", that is, the ON signal, arrives at the NPN transistor 43, a current flows from the positive power source 45 side to the controller 5, and the fail lamp 46 blinks. Here, noise of the ON signal may be output from the comparator 39 due to chattering or the like even when none of the G sensors is out of order. As described above, the low pass filter 41 and the Schmitt trigger are used. Since 42 is designed to block the ON signal from the comparator 39 caused by chattering, the fail lamp 46 does not blink in such a case. Further, according to the above method, the driver is informed of the failure of the G sensor by the fail lamp 46 only during the time when the signals input to the comparator 39 are different, but the driver concentrates on driving. Fail lamp
Since there are cases where the blinking of 46 is not noticed, in order to avoid such a case, a well-known timer circuit may be added to point A in FIG. 1 to increase the blinking time. It is also possible to provide a holding circuit for and keep blinking until the ignition key is turned off.

As described above, according to this embodiment, when any one of the G sensors fails, the failure notification means can notify the driver of the failure.

On the other hand, the signals sent from the G sensors 11A and 11a during braking when traveling on a high μ road are also input to the not circuits 20A and 20a, and the logic circuit used in this embodiment receives the ON signal. In this case, the logic "1" is output when the ON signal is not received, and the logic "0" is output when the ON signal is not received. Therefore, the logic "1" is output from either the not circuit 20A or 20a. , The other side outputs the logic "0" to the nor circuit 21, and the nor circuit 21 outputs the logic "0" to the NPN transistor 22 when the vehicle runs on the high μ road.
When a logic "0" is output from the logic circuit group 100 including the not circuits 20A and 20a and the nor circuit 21, the positive power source 2
Power supply from the 3rd side to the controller 5 is cut off, and the controller 5 determines that the vehicle is traveling on a high μ road.

When braking on low μ road, G sensor 11
An ON signal is sent from both A and 11a, and the not circuit 20A,
Outputs that are both inverted from 20a, that is, logic "0" is n
It is output to the OR circuit 21, and the NPN transistor 22 is output from the NOR circuit 21.
A logic "1" is output to when driving on a low μ road. And NP
When logic "1" flows through N-transistor 22, plus power supply 2
A current starts flowing from the 3 side to the controller 5, and the controller 5 determines that the vehicle is traveling on a low μ road.

As described above, in this embodiment, even if one of the G sensors has an ON failure, it is possible to always provide the controller 5 with a signal that matches the road surface condition.

In the above embodiment, the logic circuit group 100 is connected to the not circuit 20.
Although it is configured by A and 20a and the nor circuit 21, it is of course possible to use one and circuit that exhibits the same function in place of the logic circuit group 100.

In the above embodiment, the driver is informed of the failure of the G sensor by blinking the fail lamp. However, the fail lamp may be turned on as well as the turn-on of the fail lamp of the fail safe circuit. If it is confusing, a failure alarm lamp for the G sensor may be newly provided and turned on or blinked, or may be notified by a failure notification means such as a buzzer.

Further, in the above-mentioned embodiment, an example in which two G sensors are used is shown, but the present invention can be carried out in the same way even if there are three or more G sensors, and even if only one signal is input to the comparator, a failure alarm is issued. All that is required is to activate the means. In that case, it is needless to say that if there is at least one normal G sensor, normal anti-skid control is performed even if all other than that one have an ON failure.

(Effect) As described above, according to the present invention, if any of the plurality of G sensors used in the anti-skid control device fails, the driver is informed of the failure. The anti-skid control device can be further improved in reliability, and even if one of the G sensors fails, another G sensor can be used when braking on a high μ road. Since the control for the high μ road is executed by turning the sensor off, the inconvenience caused by the ON failure of the G sensor can be eliminated, and the control reliability is improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an anti-skid control device showing an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram of a G sensor showing a conventional technique. 1, 11, 11A, 11a ... G sensor for anti-skid control,
2a, 12A, 12a ... lowest point, 2b, 12B, 12b ... inclined groove,
3, 13A, 13a ... Reed switch, 4, 14A, 14a ... Mercury bulb, 39 ... Comparator, 46 ... Failure notification means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Masayuki Hashiguchi 5-3-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation (56) Reference JP-A-57-139815 (JP, A) JP-A-SHO 60-255561 (JP, A) Actual opening 60-104772 (JP, U) Actual opening 55-55764 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A wheel speed sensor for detecting a wheel speed, a plurality of G sensors which are normally turned on and turned off when a deceleration of a predetermined amount or more acts on a vehicle body, and an actuator which adjusts a braking force acting on a wheel. It has a control means for controlling the operation of the actuator in response to the output of each sensor, and a failure notification means for reporting a failure of the G sensor, and the control means turns on all of the plurality of G sensors. Control for the low μ road is executed and at least one of the plurality of G sensors executes control for the high μ road when off, while the output signals of the plurality of G sensors are compared with each other. If the signals are different from each other, the anti-skid control device is configured to operate the failure notification means.