JPH028936B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a rotation detector that detects the rotational speed of wheels on both sides of a vehicle, and a rotation detector that is connected to each of these rotation detectors and detects the deceleration of the wheels. regulating channels including slip and acceleration limit value circuits for processing the output signal of the rotation detector to generate a braking pressure regulating signal; and an output amplifier and a braking pressure regulating solenoid valve respectively connected to these regulating channels. a braking circuit forming a wheel braking pressure that is each controlled in dependence on the output signal of the regulating channel;
The present invention relates to a circuit device for improving running stability of a vehicle having an anti-sticking braking device.

[Conventional technology]

In such anti-sticking braking devices, the braking pressures of the wheels on both sides are individually controlled by adjustment circuits belonging to each of these wheels (individual adjustment).
This has the advantage of short braking distance.
However, if the road surface friction coefficients of the wheels on both sides of the vehicle are different, this anti-sticking braking device has the disadvantage that the yawing moment about the vertical axis of the vehicle becomes large and the running stability of the vehicle is lost.

The adjustment channel for wheels that tend to stick earlier during braking, i.e. wheels with a lower coefficient of road friction,
It has also been proposed to jointly control (common control) the braking pressures of the braking circuits belonging to wheels that do not yet show a tendency to stick, that is, wheels with a higher coefficient of road friction. This is called a low-selective adjustment, in which brake pressure adjustments are made for all wheels if any one wheel shows a tendency to stick. With such a low selection adjustment, even if the road friction coefficients on both sides of the vehicle are different, the yaw moment is kept small and the running stability of the vehicle is improved.

However, in such low selection adjustment, the problem is how to identify the wheel with the lower road surface friction coefficient and switch to the low selection adjustment.

[Problem to be solved by the invention]

The object of the invention is that when the wheel with the lower coefficient of road friction shows a tendency to stick, the wheel braking pressure is reduced by means of the regulating channel belonging to this wheel and is therefore lower than the braking pressure of the other wheel with the higher coefficient of road friction. The objective is to easily identify the wheel with the lower coefficient of road friction and switch to low selection adjustment, thereby reducing the yawing of the vehicle and improving running stability.

[Means to solve the problem]

In order to solve this problem, the present invention provides a discriminator circuit that is attached to both adjustment channels and that compares the braking pressures of both wheels and generates an output signal when the braking pressure difference exceeds a predetermined value. A switching device is provided for connecting an adjustment channel attached to a wheel having a lower braking pressure to a braking circuit of a wheel having a higher braking pressure in response to an output signal of the circuit, thereby performing common control of both braking circuits. It is being

〔Effect of the invention〕

Thus, according to the present invention, the wheel with the lower coefficient of road friction is easily determined using the discrimination circuit based on the braking pressure difference of a predetermined value or more between the wheels on both sides, and is switched to low selection adjustment by the switching device. This reduces vehicle yaw and improves driving stability. In this case, a pressure switch or a pressure generator (transmitter) as pressure sensor can be used as part of the monitoring device in the regulating channel, and its output signal is compared with a comparator. , a signal may be generated that energizes the switching device at a signal output difference greater than or equal to a predetermined value.

〔Example〕

In the figure, a rotation detector 90 detects the rotation speed of one wheel, and a rotation detector 92 detects the rotation speed of the other wheel. Detectors 90 and 92
The output signals of are connected to adjustment channels 86 and 8, respectively.
8, in which the output signals of the detectors are processed by limit value circuits (not shown) for acceleration, deceleration and slippage of the wheels to form adjustment signals for the braking pressure. The regulation channel can also include a regulation signal and/or a monitoring device for the brake pressure regulating solenoid valve of the brake circuit. The output signals of the adjustment channels 86, 88 are transmitted to the brake circuits 102, 104, which include a power amplifier and a brake pressure regulating solenoid valve.
are supplied to each. Adjustment channels 86, 88
are each associated with a discriminator circuit 94, 96, such as a pressure switch or pressure generator, which detects the regulated braking pressure in the braking circuits 102, 104 as part of a monitoring device, not shown, included in the regulating channel. It also includes a pressure detector and a comparator that generates a switching signal when the output signals of both pressure detectors differ by more than a predetermined value. Depending on the output signals of the discrimination circuits 94, 96, one or the other adjustment channel 8
6, 88 to the other or one braking circuit 104, 1
The switching devices 98, 100 for switching to 02 are configured as logic circuits and include AND gates 106 and 108 and an OR gate 110, respectively.

Now, if the road surface friction coefficient of the wheel to which the rotation detector 92 belongs is lower than the road surface friction coefficient of the wheel to which the rotation detector 90 belongs, the wheel with the lower road surface friction coefficient tends to stick earlier, and the adjustment channel 88 The braking pressure in the braking circuit 104 is reduced to begin the anti-sticking process. Therefore, at this time, the braking pressure of the wheel to which the braking circuit 102 belongs is higher than the braking pressure of the wheel to which the braking circuit 104 belongs.

If the braking pressure difference between the two wheels is greater than a predetermined value, the discrimination circuit 94 associated with the regulating channel 86 whose braking pressure is higher, for example by a predetermined value, generates a high level signal, which signals the logic of the switching device. reaching the negative input of the AND gate 106 of the circuit 98, blocking this AND gate and making another AND gate 108 of this logic circuit 98 conductive for the regulation signal coming from the further regulation channel 88; Via the OR gate 110, the brake circuit 102 is controlled together with the brake circuit 104 by a regulation channel 88 with a lower brake pressure (low selection regulation).

[Brief explanation of drawings]

The figure is a connection diagram of an embodiment of the present invention. 86, 88...adjustment channel, 90, 92...
Rotation detector, 94, 96...Discrimination circuit, 98, 1
00...Switching device (logic circuit), 102,10
4...braking circuit.

Claims (1)

[Claims] 1. Rotation detectors for detecting the rotational speeds of the wheels on both sides of the vehicle, respectively, and limit value circuits for wheel deceleration, slip, and acceleration connected to these rotation detectors, respectively, and processing the output signals of the rotation detectors. a modulation channel for generating a braking pressure modulation signal;
a braking circuit connected to each of these regulating channels and including an output amplifier and a brake pressure regulating solenoid valve and forming a wheel braking pressure that is respectively controlled in accordance with an output signal of the regulating channel; Discrimination circuits 94 and 96 are attached to the wheels 86 and 88, respectively, and compare the braking pressures of both wheels and generate an output signal when the braking pressure difference exceeds a predetermined value, and this discriminating circuit 94 or 9
Depending on the output signal of 6, the adjustment channel 88 or 86 associated with the wheel with the lower brake pressure is also connected to the brake circuit 102 or 104 of the wheel with the higher brake pressure, so that both brake circuits 102, 104 are connected. 1. A circuit device for improving running stability of a vehicle having an anti-sticking braking device, characterized in that switching devices 100 and 98 for common control are provided.