KR100751231B1 - System for controlling the stability of vehicles - Google Patents

Abstract

The present invention relates to a stability control system of a vehicle, and more particularly, to a stability control system of a vehicle to determine whether a sudden braking is applied in a braking state by a driver to generate a sufficient braking hydraulic pressure for each wheel.

The present invention as described above,

A first step of determining whether the brake control is currently in progress, a second step of determining whether the brake is released under the sudden braking control, a third step of stopping the sudden braking control if the brake is released, and a sudden braking control condition in the first step Otherwise, the fourth system determines whether the sudden braking control condition is applied, and if the sudden braking control condition is performed, performing rapid braking control.

Rapid braking, pressure sensor

Description

System for controlling the stability of vehicles}

1 is a hydraulic circuit diagram showing the configuration of an electronically controlled brake system for a vehicle according to the present invention.

2 is a block diagram showing the configuration of a control unit according to the present invention;

3 is a control flowchart of the present invention.

* Description of the symbols for the main parts of the drawings *

1: pressure sensor 2: control unit

2a: pressure change rate determination unit 2b: rapid braking control unit

40: hydraulic modulator

The present invention relates to a stability control system of a vehicle, and more particularly, to a stability control system of a vehicle to determine whether a sudden braking is applied in a braking state by a driver to generate a sufficient braking hydraulic pressure for each wheel.                         

In general, the anti-lock brake system (hereinafter referred to as ABS) is to prevent the wheel from locking by appropriately adjusting the braking pressure applied to the wheel according to the slip ratio calculated from the wheel speed. The TCS (hereinafter referred to as TCS) is to control the driving force of the engine to prevent excessive slippage during sudden start or acceleration of the vehicle.

The anti-lock brake system (ABS) and traction control system (TCS) can perform well when the vehicle is driving on a straight road, but when steered on a curve road, the understeer is excessively inclined outward. Can occur and, conversely, over steer can occur that is excessively inward.

Therefore, there is a demand for a vehicle stability system (hereinafter referred to as an electronic stability program ESP) to stably control a vehicle's posture under any circumstances in which the vehicle travels, that is, to prevent steering loss of the vehicle. For example, in a situation where an under steer is pushed out of a desired driving trajectory when turning, a braking force is applied to the rear wheels to prevent the vehicle from being pushed outward and the turning speed of the vehicle is increased. In a situation where an excessively large oversteer is inclined inward on a desired driving trajectory, a braking force is required to the front wheels.

In order to control vehicle stability during turning, the performance of the system is determined by accurately predicting the turning speed of the driver's desired vehicle and by applying the appropriate braking pressure to the front and rear wheels to drive the vehicle according to the predicted turning speed. do.

In addition, in controlling the stability of the vehicle, the performance of the above-described ABS and TCS should not be impaired. On the contrary, the stability of the vehicle is not adversely affected by the ABS and the TCS. Therefore, in order to control the safety of the vehicle appropriately in the state of movement of the vehicle, it is desirable to focus on cooperative control in conjunction with the existing ABS and TCS.

The conventional vehicle stability system as described above reduces the vehicle speed by forming a braking pressure on the wheel of the vehicle when the driver operates the brake pedal. However, the elderly and female drivers do not form sufficient operating force in a situation where rapid braking is to be performed. There is a problem that the braking distance is long. As the braking distance increases during braking, the possibility of colliding with a vehicle or an object in front of the vehicle increases, thereby failing to secure driver safety.

The present invention for solving the above problems is to provide a vehicle stability control system to determine the start and end of the sudden braking using the sensing data of the pressure sensor configured in the master cylinder, and to perform the braking control corresponding to the sudden braking .

The present invention for achieving the above object,

A first step of determining whether the brake control is currently in progress, a second step of determining whether the brake is released under the sudden braking control, a third step of stopping the sudden braking control if the brake is released, and a sudden braking control condition in the first step Otherwise, the fourth system determines whether the sudden braking control condition is applied, and if the sudden braking control condition is performed, performing rapid braking control.

The second step is characterized in that if the rate of change of the pressure sensor configured in the master cylinder is less than the set value or the value of the current pressure sensor is less than the set value it is determined as a sudden braking release condition.

The fourth step is a step of determining whether the change rate of the pressure sensor configured in the master cylinder is greater than the set value, if the set value is exceeded, it is determined whether the value of the current pressure sensor is greater than the set value, and if the set value is exceeded, it is determined as a sudden braking condition. do.

The configuration of the present invention for performing the above operation,

A master cylinder for forming a braking pressure when a driver operates the brake pedal, a pressure sensor for measuring the pressure of the discharge hydraulic pressure of the master cylinder, and a plurality of opening and closing the discharge hydraulic pressure of the master cylinder on the wheel cylinder side. TC valves, a plurality of solenoid valves for blocking and opening the hydraulic pressure discharged from the master cylinder to the wheel cylinder side to perform a braking operation, a pump for sucking and supplying the hydraulic pressure applied to the wheel cylinder to the master cylinder; A vehicle comprising a motor for driving the pump, an oil suction passage for guiding the oil of the master cylinder to be sucked into the inlet of the pump in the TCS mode, and a shuttle valve configured to open and close the suction passage in the oil suction passage. The speed of the vehicle currently driving by inputting the sensing value of the pressure sensor It characterized in that it is configured to include a control unit which controls the dynamic braking control start and control release.

The control unit inputs a sensing value of the pressure sensor to measure the rate of change, a pressure change rate measuring unit, and inputs a sensing value of the pressure change rate measuring unit and the pressure sensor to start the braking control of the currently running vehicle and the braking control release control And a rapid braking control unit for outputting a signal.

The rapid braking control is performed by turning off the TC valve, opening the shuttle valve, sucking the discharge hydraulic pressure of the master cylinder from the pump, and supplying it to each wheel cylinder.

The braking release may be performed by closing the shuttle valve and opening the TC valve.

Hereinafter, the detailed configuration and operation of the present invention will be described with reference to the accompanying drawings.

1 is a hydraulic circuit diagram showing a configuration of an electronically controlled brake system for a vehicle according to the present invention, Figure 2 is a block diagram showing the configuration of a control unit according to the present invention, Figure 3 is a control flowchart of the present invention.

First, referring to the hydraulic circuit with reference to FIG.

Electronically controlled brake system for a vehicle according to the present invention is connected to the primary port 21 of the master cylinder 20 and two wheel cylinders 30 to control the hydraulic pressure transmission 40A and the master cylinder ( The secondary hydraulic circuit 40B for connecting the secondary port 22 and the remaining two wheel cylinders 30 to control hydraulic pressure transmission, and a control unit for controlling the electric driving element (see FIG. 2; 2) It is equipped with, they are installed compactly in the modulator block (40).

The primary hydraulic circuit 40A and the secondary hydraulic circuit 40B are solenoid valves 41 and 42 for controlling braking hydraulic pressure transmitted to two wheel cylinders 30, respectively, and the wheel cylinder 30. A pump 44 for sucking and pumping oil from the oil or master cylinder 20 discharged from the side, a low pressure accumulator 43 for temporarily storing the oil exiting the wheel cylinder 30, and the pump 44 from the pump 44. A high pressure accumulator 46 for reducing pressure pulsation from the hydraulic pressure being pumped, and an oil suction passage 48a for guiding the oil of the master cylinder 20 to be sucked into the inlet of the pump 44 in the TCS mode.

The plurality of solenoid valves 41 and 42 are associated with the upstream and downstream sides of the wheel cylinders 30, which are normally open solenoid valves disposed upstream of each wheel cylinder 30 and kept in an open state. (41) and a normal closed solenoid valve 42 disposed downstream thereof and kept normally closed. The opening / closing operation of the solenoid valves 41 and 42 is controlled by the control unit 2 which detects the vehicle speed through a wheel sensor (not shown) disposed on each wheel side, and the normally open solenoid valve 42 according to the decompression braking. ) Is opened and the oil exiting from the wheel cylinder 30 side is temporarily stored in the low pressure accumulator 43.

The pump 44 is driven by the motor 45 to suck the oil stored in the low pressure accumulator 43 and discharge it to the high pressure accumulator 46 side (in ABS boosting or holding mode), so that the hydraulic pressure is transferred to the wheel cylinder 30 side or the like. The transfer to the master cylinder 20 side.                     

In addition, an NO solenoid valve 47 (hereinafter referred to as TC valve) for traction control control is provided in the main flow passage 47a connecting the master cylinder 20 and the outlet of the pump 44. The TC valve 47 is normally kept open, and the braking hydraulic pressure generated in the master cylinder 20 during normal braking through the brake pedal 10 is transmitted to the wheel cylinder 30 through the main flow passage 47. .

In addition, the oil suction flow passage 48a branches from the main flow passage 47 to guide the oil of the master cylinder 20 to be sucked to the inlet side of the pump 44, where the oil flows only into the pump 44 inlet. Shuttle valve 48 is provided. That is, the electrically operated shuttle valve 48 is installed in the middle of the oil suction flow path 48a, and is normally closed and operates to open in the TCS mode.

As shown in FIG. 2, the controller 2 is

Input the sensing value of the pressure sensor 1 and the pressure change rate measuring unit 2a for measuring the rate of change and the sensing value of the pressure change rate measuring unit 2a and the pressure sensor 1 by inputting the And a sudden braking control section 2b for outputting a sudden braking control start and a sudden braking control releasing control signal.

As shown in FIG. 3, the control process of the present invention configured as described above includes a first step of determining whether the current brake control is in progress, a second step of determining whether the sudden braking release condition is applied during sudden braking control, and a sudden braking release condition. A third step of stopping the sudden braking control; a fourth system for determining whether the sudden braking control condition is not the sudden braking control condition in the first step; and a sudden braking control if the sudden braking control condition is performed.                     

The detailed operation is as follows.

When the brake pedal 10 is operated by the driver and a braking pressure is formed in the master cylinder 20, the controller 2 inputs a braking pressure value detected by the pressure sensor 1 configured in the master cylinder 20.

The pressure change rate determination unit 2a of the controller 2 inputs the pressure value detected by the pressure sensor 1 to calculate the change rate, that is, the slope.

The sudden braking control unit 2b of the control unit 2 inputs values output from the pressure change rate determining unit 2a and the pressure sensor 1 to determine the braking control of the current vehicle.

First, it is determined whether the change rate ΔP calculated by the pressure change rate determination unit 2a is greater than a preset value. That is, it is determined whether the rate of increase of the braking pressure by the driver is greater than or equal to the set value, and if it is greater than or equal to the set value, it is determined whether the pressure value sensed by the current pressure sensor 1 is greater than or equal to a preset value.

In other words, as described above, the quick braking control unit 2b determines that the braking situation is performed when the rate of increase of the braking pressure and the current pressure value are each higher than or equal to a preset value.

If it is determined as described above that the start of the sudden braking control, the sudden braking control unit 2b outputs a sudden braking control signal to the hydraulic modulator 40,

As shown in FIG. 1, the TC valve 47 is closed and the shuttle valve 48 is opened to supply a braking pressure through the suction flow path 48a.                     

That is, the braking is performed by the pump 44 sucks the hydraulic pressure discharged from the master cylinder 20 through the suction flow path 48a and provides it to the wheel cylinders 30.

The release of the sudden braking control is performed when the rate of change of the pressure of the master cylinder 20 is less than the preset value or the pressure value sensed by the pressure sensor 1 is less than the preset value. It stops and performs general braking control.

 As described above, in the present invention, a sudden braking control is performed even if an emergency situation occurs for the elderly or female driver by determining the braking start and release using the pressure sensor configured in the master cylinder, thereby reducing the braking distance, thereby reducing the reliability of the driver or the user. To provide a stability control system for a vehicle.

Claims (7)

delete delete delete delete In the vehicle stability control system, A first step of judging whether the braking control is currently in progress; a second step of judging whether the braking release condition is in the case of sudden braking control; a third step of stopping the sudden braking control in the case of the sudden braking release condition; Otherwise, a fourth step of determining whether or not a sudden braking control condition is performed; and a fifth step of performing rapid braking control if the sudden braking control condition is performed, The second step is a stability control system for a vehicle, characterized in that the determination of the sudden braking release condition if the rate of change of the pressure sensor configured in the master cylinder is less than the set value or the current pressure sensor is less than the set value. delete In the vehicle stability control system, A first step of judging whether the braking control is currently in progress; a second step of judging whether the braking release condition is in the case of sudden braking control; a third step of stopping the braking control in the case of the sudden braking release condition; Otherwise, a fourth step of determining whether or not a sudden braking control condition is performed; and a fifth step of performing rapid braking control if the sudden braking control condition is performed, The fourth step is a step of determining whether the change rate of the pressure sensor configured in the master cylinder is greater than the set value, and if the set value is exceeded, it is determined whether the value of the current pressure sensor is greater than the set value, and if the set value is exceeded, it is determined as a sudden braking control condition. Vehicle stability control system.

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