JPS6228023B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises: at least one sensor that generates a sensor signal proportional to the rotational speed of a wheel; a differentiator circuit that differentiates the sensor signal to generate an acceleration signal and a deceleration signal; A limit value circuit generates an acceleration control signal and a deceleration control signal at acceleration and deceleration signals above a limit value, and a circuit forms a slip control signal from the sensor signal and generates an acceleration control signal or a deceleration signal when braking is controlled. a pulse device that receives a speed control signal and applies a pulse to a solenoid valve for braking pressure control, and suppresses a disturbance signal when it occurs to prevent malfunction of the braking device;
The present invention relates to a circuit device for preventing erroneous control signals of a vehicle braking device from sticking.

During normal driving, pitching, rolling, and vertical vibration of the vehicle body may occur due to road irregularities, and changes in the distance from the road surface to the center of the wheel, that is, the rolling radius of the wheel, may occur in relation to the load. This change in rolling radius is detected by a sensor that detects the rotational speed of the wheel. If the temporal change is large enough to exceed the deceleration limit value, a control process is initiated in the electronic control unit. If such changes in the rolling radius occur rapidly over time, a control process is initiated at an appropriate frequency. Due to the braking operations carried out in this case, the components of the anti-sticking device can reach their service life limits and break down within a very short time.

The object of the invention is to prevent erroneous control signals that occur due to changes in the rotational speed of the wheels that are not caused by braking operations, in particular due to changes in the rolling radius of the wheels.

In order to solve this problem, according to the present invention, an acceleration control signal or a deceleration control signal is supplied to a frequency comparison circuit, the frequency thereof is compared with a predetermined value, and the output signal of this frequency comparison circuit is used as the deceleration control signal. A blocking device is provided which blocks the signal or the output signal of the pulse device.

This prevents adverse effects of changes in rotational speed caused by changes in the rotational speed of the wheels, in particular changes in the rolling radius of the wheels.

In unbraked driving, rolling radius changes can occur with a frequency of approximately 10 Hz. In a normal anti-stick control process, a control frequency of about 6 Hz or less is tolerated without degrading the quality of the control, so there is a risk of an erroneous control course; however, the present invention eliminates this risk. Avoided.

In controlled braking, a specific order of control signals is expected. In general, the control process is started upon generation of the deceleration control signal and is usually followed by a slip control signal with a time lag. However, this slip control signal requires a control amplitude of a certain magnitude. In the case of rolling radius changes in unbraked running conditions, the slip does not exceed the limit value, but when the deceleration limit value that controls the pulse device is exceeded, the pulse device controls the solenoid valve after the disappearance of the deceleration control signal. . Now, if the order of control signals expected in a normal control process is not maintained, this must be considered as containing an error. In order to avoid erroneous control caused by this, according to the present invention,
A device is provided which can be switched by the slip control signal and generates an output signal, which output signal is logically combined with the output signal of the pulse device or the deceleration control signal in an AND gate, the output end of the AND gate being connected to the solenoid valve. has been done.

The invention will now be described with reference to embodiments shown in the drawings.

In unbraked driving operation, the speed changes of the wheels due to changes in the rolling radius of the wheels, and the corresponding acceleration and deceleration control signals, are determined by the control signal frequency (frequency) that is permissible in controlled and braked driving conditions, e.g. It has a frequency higher than about 6 Hz, for example 10 Hz.
Now, the circuit shown in FIGS. 1 and 2 prevents generation of a control signal due to such a change in wheel speed in an unbraked running state at a frequency equal to or higher than the frequency of the acceleration control signal.

First, let's talk about Figure 1. One or more sensors 2 detect the rotational speed of one or more wheels. Acceleration and deceleration signals are generated in differentiating circuits 4 and 6. Furthermore, a signal proportional to wheel slippage is obtained in circuit 8 and is used for control as a slippage control signal (λ signal).
The output signal of the differentiating circuit 4 is given to a comparator 10 as a limit value circuit with a small limit value, and a signal exceeding this limit value is used as an acceleration control signal (+b signal) in the frequency comparator circuit 12 to output a target value of, for example, 6Hz. compared to the value. When this target value is exceeded, the comparator circuit 12 generates a high level signal which passes through the NOT gate 14 as a low level signal to the input of the AND gate 16 and blocks this gate. The output signal of the differentiating circuit 6 is compared with a predetermined limit value in a comparator 18 as a limit value circuit, and when this limit value is exceeded, a deceleration control signal (-b signal) is generated as a control signal.
It reaches the other input end of AND gate 16. This AND
Since the gate is blocked, the -b signal which normally initiates the control process cannot be activated and the control of the solenoid valve 20 is controlled by the OR gate 22 and the amplifier 2.
4.

When a controlled and braked driving condition exists, the -b signal is passed through the OR gate 22 to the solenoid valve 20.
and at the same time reset, via an OR gate 26, a pulse device 28 which forms a pulse signal from the continuous signal by its interruption, and further lengthens, shortens or delays the pulse signal by a delay in response or return. , in this case applied to the return delay timer 30. This timing element 30 is -b
After the signal disappears, it continues to operate for a delay time, and the high level output signal of this timer is supplied as a low level signal to the reset input R of the pulse device 28 via the NOT gate 32 and the OR gate 26, so that the timer remains in operation. A pulse device 28 generates pulses to control the solenoid valve 20 while the device continues to operate. After the timing element 30 has finished operating, its output signal goes to a low level signal and the pulse device 28 is blocked again.

Since the circuit according to FIG. 2 substantially corresponds to the circuit according to FIG. 1, the same numerical symbols and dashes have been used for the same components. Since the -b signal is blocked by the +b signal when the frequency limit is exceeded, the AND gate is no longer blocked as in FIG. 1, and the amplitude limit of the -b signal comparator 18' is can be enhanced.

In the case of controlled braking a fixed sequence of control signals can be expected. In general, the control process is started on the occurrence of the -b signal, and is usually shifted in time to λ
The signal will continue. However, this λ signal requires a control amplitude of a certain magnitude. When the rolling radius of the wheels changes in unbraked driving conditions, the slip limit is not exceeded, but the deceleration limit that controls the pulse device is exceeded in response.
The pulse device switches the solenoid valve after the disappearance of the -b signal. Now, if in the normal control process the expected order of the various control signals is not maintained, this must be considered a case of error. Circuits for preventing erroneous control in such cases are shown in FIGS. 3, 4, 5, and 6. The embodiments shown in FIGS. 3 and 6 are also provided with an acceleration signal differentiation circuit and a comparator as in FIGS. 4 and 5, but these are omitted for the sake of simplicity.

Referring first to FIG. 3, from the signal obtained from the sensor 40, a differentiating circuit 42 forms a deceleration signal, and a circuit 44 forms a λ signal. The deceleration signal is compared to a predetermined limit value in comparator 46, and if this limit value is exceeded, a -b signal is generated and output to OR gate 48 and amplifier 50.
Control the solenoid valve 52 (inlet valve) through the
The pulse device 54 is reset via the OR gate 56 and also controls the timing element 58. The output terminal of this time element 58 is connected to a NOT gate 60 and an OR
It is connected via a gate 56 to the reset input R of the pulse device 54. The pulse device 54
It is connected to the solenoid valve 52 via the input end of the AND gate 62 . The output terminal Q of an RS flip-flop 64 is connected to the other input terminal of the AND gate 62, and the set input terminal S of this flip-flop is connected.
is connected to the output terminal of the λ signal generating circuit 44, and its reset input terminal R is connected via a NOT gate 66 to the output terminal of a return delay time element 68, which receives the control signal of the solenoid valve 52. If there is an error as described above, the -b signal first controls solenoid valve 52 and resets pulser 54. The timer 58 continues to operate after the disappearance of the -b signal and resets the flip-flop 64 after its operation, the low level output signal of which blocks the AND gate 62, so that the pulse of the pulser 54 causes the solenoid valve 52 to The control of is blocked after the operation of the timing element 58 has elapsed. Under normal control, after a certain time lag the λ signal will subsequently set the flip-flop 64, thereby
AND gate 62 becomes conductive.

The circuit according to FIG. 4 includes more circuit elements than those of FIG. The main difference between this circuit and the circuit according to Figure 3 is that unless control of the outlet valve is
In order to block the b signal, a response delay time element is provided.

Now, from the signal of the sensor 70, the differentiation circuit 72
Comparator 78 generates a +b signal, differentiation circuit 74 and comparator 80 generate a -b signal, and circuit 76 generates a λ signal.

The output terminal of the comparator 78 is ORed with the AND gate 82.
It is connected to a solenoid valve (inlet valve) 86 via a gate 84 . The output terminal of the comparator 80 is first OR
connected to inlet valve 86 via gate 84;
connected to an outlet valve 90 via an OR gate 88;
Further, via an OR gate 92, a reset input terminal R of a pulse device 94 is connected to a return delay timer 9.
It is connected to the input terminal of 6. The output of this timing element is connected via a NOT gate 98 and an OR gate 92 to a reset input R of a pulse device 94. Reset input terminal R of pulse device 94
is further connected to the output of AND gate 82, and the input of outlet valve 90 is connected to a response and return delay timer 100 whose output is connected via NOT gate 102 to the reset input of flip-flop 104. connected to R, and
It is connected to the other input terminal of AND gate 82.

The outputs of pulse device 94 and flip-flop 104 are connected to the inputs of AND gate 106;
The output end of this AND gate is connected to the inlet valve 86. The set input S of flip-flop 104 is connected to a λ signal generation circuit 76, as in the circuit according to FIG.

The +b signal passing through comparator 78 is applied to timing element 1
00 is inactive and is therefore blocked by gate 82 as long as the output of this timer is zero. In this case, flip-flop 104 is also reset. The -b signal first resets the pulse device 94 and also reaches the outlet valve 90 and timing element 100. -b signal and therefore the control signal is lost, timer elements 96 and 100 continue to operate, so that pulser 94 is set again and AND gate 82 becomes conductive.

After the operation of timer 100 is completed, flip-flop 104 is reset, thereby blocking AND gate 106, thereby preventing control of inlet valve 86 by pulse device 94, and again blocking AND gate 82.

Due to the setting of flip-flop 104
AND gate 106 is first turned on by the generation of the λ signal.

The circuit according to FIG. 5, in which the same parts as in FIG. 4 are given the same numerical symbols and dashes, differs from the circuit according to FIG. 4 in the following points. That is, blocking of AND gate 82' is done via flip-flop 104' instead of via return delay timer 100.

The circuit according to FIG. 6 substantially corresponds to the circuit according to FIG. 3, so that in this case also the corresponding numerical symbols are marked with a dash. In the circuit according to FIG. 6, the blocking of the pulse device 54' is not effected by blocking the AND gate 62' via the flip-flop 64'. AND gate 62' is connected to comparator 46' and flip-flop 62' is connected to comparator 46'.
Blocks the -b signal while 4' is reset.

When a short -b signal train occurs, the seventh
The circuit shown in the figure can be used.

The +b and -b signals are generated by differentiating circuits 110 and 112 and comparators 114 and 116, and the λ signal is generated in circuit 118.

When a -b signal of appropriate magnitude is generated, solenoid valves 120 and 122 are controlled. At the same time, the -b signal is also supplied to the response and return delay timing element 124, the response delay of which is of such a magnitude that a short -b signal sequence is temporally included. This allows the AND gate 126 to block the pulse device 128 for a sufficiently long time so that the pulse generated in each case after the disappearance of the -b signal is transmitted to the solenoid valve 12.
0 cannot be controlled, thereby avoiding harmful high control frequencies.

[Brief explanation of the drawing]

1 to 7 are block diagrams of different embodiments of the circuit arrangement according to the invention. 2, 2', 40, 40', 70, 70'...sensor, 4, 4', 6, 6', 42, 42', 72, 7
2', 74, 74', 110, 112... Differential circuit, 8, 8', 44, 44', 76, 76', 11
8... Signal generation circuit, 10, 10', 18, 1
8', 46, 46', 78, 78', 80, 80',
114, 116...Limit value circuit (comparator), 1
2, 12'...Frequency comparison circuit, 16, 34, 1
26...Blocking device, 20, 52, 52', 86,
86'...Solenoid valve, 28, 28', 54, 94, 9
4', 128...Pulse device, 62, 62', 10
6,106'...AND gate, 64,64',1
04, 104'... Device switchable by λ signal, 124... Timing element.

Claims (1)

[Claims] 1. At least one sensor that generates a sensor signal proportional to the rotational speed of the wheel, a differentiation circuit that differentiates the sensor signal to generate an acceleration signal and a deceleration signal, and A limit value circuit for generating acceleration and deceleration control signals in the acceleration and deceleration signals and a circuit for forming the slip control signal from the sensor signal and for generating the acceleration or deceleration control signal if braking is controlled. and a pulse device that applies a pulse to a solenoid valve for braking pressure control in order to prevent a malfunction of the braking device by suppressing a disturbance signal when it occurs, the acceleration control signal or deceleration control signal has a frequency It is supplied to a comparator circuit 12, 12' and its frequency is compared with a predetermined value, and the output signal of this frequency comparator circuit is used as a deceleration control signal or a pulse device 2.
a blocking device 16 for blocking the output signals of 8, 28';
34. A circuit device for preventing erroneous control signals of a vehicle braking device that is prevented from sticking. 2. The blocking device is an AND gate 16, and the negative output signal of the frequency comparison circuit 12 is the acceleration control signal and the deceleration control signal.
6, and this AND gate 16
The circuit device according to claim 1, characterized in that an output end of the solenoid valve 20 is connected to the solenoid valve 20. 3. The blocking device is connected to the deceleration control signal limit value circuit 1.
8. Circuit arrangement according to claim 1, characterized in that it is a device 34 for increasing the limit value of 8'. 4. At least one sensor that generates a sensor signal proportional to the rotational speed of the wheel, a differentiation circuit that differentiates the sensor signal and generates an acceleration signal and a deceleration signal, and an acceleration signal and a deceleration signal that are greater than a predetermined limit value. a limit value circuit for generating an acceleration control signal and a deceleration control signal, a circuit for forming a slip control signal from the sensor signal, and a circuit for receiving an acceleration control signal or a deceleration control signal for braking pressure control when braking is controlled; In a device that has a pulse device that applies a pulse to a solenoid valve, and prevents malfunction of the braking device by suppressing a disturbance signal when it occurs, the blocking device that blocks the output signal of the pulse device 128 is an AND gate 126. and the output terminal of the pulse device 128 and the output terminal of the response and return delay time element 124 are connected to the two input terminals,
A circuit device for preventing erroneous control signals of a vehicle braking device from sticking, characterized in that a timing element 124 receives a deceleration control signal supplied to a solenoid valve 122. 5 at least one sensor that generates a sensor signal proportional to the rotational speed of the wheel; a differentiation circuit that differentiates the sensor signal to generate an acceleration signal and a deceleration signal; and an acceleration signal and a deceleration signal that are greater than or equal to a predetermined limit value. a limit value circuit for generating an acceleration control signal and a deceleration control signal, a circuit for forming a slip control signal from the sensor signal, and a circuit for receiving an acceleration control signal or a deceleration control signal for braking pressure control when braking is controlled; A device 64, 104 that is switchable by a slip control signal and that generates an output signal, in a device that has a pulse device that applies a pulse to a solenoid valve, and suppresses a disturbance signal when it occurs to prevent malfunction of the braking device. , 104', 64' are provided, and this output signal is sent to the pulse devices 54, 94,
94' output signal or deceleration control signal in AND gates 62, 106, 106', 62', and the output terminal of this AND gate is connected to the solenoid valve 5.
2, 86, 86', and 52'. 6 device 64 switchable by slip control signal;
Reference numerals 104, 104', and 64' designate RS flip-flops, to which a slip control signal is applied to the set input terminal S, and whose reset input terminal (R) is the negation of the return delay time elements 68, 100, 100', and 68'. 6. Circuit arrangement according to claim 5, characterized in that it is connected to the output terminal and that this timing element receives a deceleration control signal supplied to the solenoid valve. 7. Claim 6, characterized in that the output signal of the timing element 100 and the acceleration control signal are logically combined in an AND gate 82, and the output end of this AND gate is connected to the electromagnetic valve 86. The circuit arrangement described. 8 The output terminal of the RS flip-flop 104' and the output terminal of the acceleration control signal limit value circuit 78' are ANDed.
7. The circuit arrangement according to claim 6, wherein the AND gate is connected to both input ends of the gate 82', and the output end of the AND gate is connected to the solenoid valve 86'. 9. The circuit arrangement according to claim 6 or 7, characterized in that the timing element 100 is configured to also perform a response delay.