Brake control system and method for preventing a vehicle from rolling downward on a slope

A brake control system for a vehicle, the system comprising:

• switching signal detecting means for detecting signals from a plurality of switches provided in the vehicle, the switching signal detecting means comprising,
• an acceleration pedal switch which outputs data as to whether or not an acceleration pedal is operated,
• a clutch switch which outputs data informing if a clutch pedal is operated,
• a brake lamp switch which outputs data as to whether or not a brake lamp is lighted,
• a neutral switch which outputs data as to whether or not a transmission is in neutral,
• a parking switch which outputs data as to whether or not a parking brake is operated, and
• a door switch which outputs data as to whether or not doors are closed;
• sensor data collecting means for collecting data from a plurality of sensors provided in the vehicle;
• gradient detecting means for detecting a road gradient;
• load detecting means for detecting a load applied to the road surface by the vehicle;
• and
• a main control unit for collecting data from the switching signal detecting means, the gradient detecting means, and the load detecting means, analyzing the data through a predetermined algorithm, and performing overall slope start control and auxiliary parking control operations.

A brake control system for a vehicle, the system comprising:

• switching signal detecting means for detecting signals from a plurality of switches provided in the vehicle;
• sensor data collecting means for collecting data from a plurality of sensors provided in the vehicle, comprising,
• an RPM sensor for sensing engine RPM,
• a speed sensor for sensing speed of a vehicle,
• a clutch stroke sensor for sensing an amount of stroke displacement applied on a clutch pedal, and
• an air pressure sensor for sensing a degree of pressure in an air tank;
• gradient detecting means for detecting a road gradient;
• load detecting means for detecting a load applied to the road surface by the vehicle;
• and
• a main control unit for collecting data from the switching signal detecting means, the gradient detecting means, and the load detecting means, analyzing the data through a predetermined algorithm, and performing overall slope start control and auxiliary parking control operations.

A brake control system for a vehicle, the system comprising:

• switching signal detecting means for detecting signals from a plurality of switches provided in the vehicle;
• sensor data collecting means for collecting data from a plurality of sensors provided in the vehicle;
• gradient detecting means for detecting a road gradient, wherein the gradient detecting means comprises a mode selection switch for driver selection of predetermined gradient levels;
• load detecting means for detecting a load applied to the road surface by the vehicle;
• and
• a main control unit for collecting data from the switching signal detecting means, the gradient detecting means, and the load detecting means, analyzing the data through a predetermined algorithm, and performing overall slope start control and auxiliary parking control operations.

A vehicle of full air type brake system comprising wheel speed sensors for sensing front and rear wheels' rotational speed of the vehicle, Anti-lock Brake System (ABS) control unit for controlling anti-lock and anti-slip brake systems after analyzing a rotation speed of each wheel detected by the wheel speed sensor, and a modulator controlling air pressure provided from an air chamber according to signals from the ABS control unit, wherein the brake system further comprises:

• a slope start control unit for integrally controlling an auxiliary slope start function and auxiliary parking function after analyzing data of vehicle conditions;
• a first and a second solenoid valves connected to an output of a dual brake cylinder for executing the slope start control by adjusting the air pressure transmitted to main relay valves according to a control signal from the slope start control unit;
• and
• a third solenoid valve placed between an air tank and the main relay valves for executing the auxiliary parking control by adjusting a post front wheel side relay valve and a post rear wheel side main relay valve according to a control signal from the slope start control unit.

A method for controlling a brake system comprising the steps of:

• determining if conditions of a vehicle are suitable for entering a slope start control mode;
• determining if air pressure in an air tank is maintained over a predetermined pressure when the conditions of the vehicle are suitable for the slope start control mode;
• maintaining a brake force without brake pedal operation by adjusting solenoid valves when the air pressure in the air tank is over a predetermined pressure;
• determining if conditions of doors, transmission gear position, clutch stroke and acceleration pedal actuation are suitable for start while the brake force is being maintained without the brake pedal operation;
• determining if a degree of a road gradient is in a predetermined range for vehicle's steady start;
• computing air pressure reducing rate for releasing the brake force according to an RPM of the engine, vehicle's weight and amount of stroke displacement applied on a clutch pedal when the degree of gradient is in the predetermined range for the vehicle's steady starting;
• releasing the brake force by opening solenoid valves according to the computed air pressure reducing rate;
• and
• controlling ABS or Anti-Slip Regulator (ASR) according to a wheel rotation speed detected by a speed sensor when an operation of the brake pedal is detected while the vehicle is operating.

A brake control system for a vehicle, the system comprising:

• a switching signal detector for detecting signals from a plurality of vehicle switches;
• a sensor data collector for collecting data from a plurality of sensors provided in the vehicle;
• a gradient detector for detecting a road gradient;
• a load detector for detecting a load applied to the road surface by the vehicle;
• a main control unit for collecting the data from the switching signal detector, the gradient detector, and the load detector, analyzing the data through a predetermined algorithm, performing slope start control and auxiliary parking control operations, and outputting signals to a plurality of solenoid valves;
• an indicator responsive to signals from the main control unit, wherein the indicator indicates whether the slope start control and auxiliary parking control operations are being performed;
• and
• an alarm for sounding an alarm during the occurrence of selected predetermined vehicle conditions.

An air brake system for a vehicle, the system comprising:

• at least one air tank for supplying air pressure to the air brake system;
• at least one front air chamber for applying air pressure to at least one front brake, and at least one rear air chamber for applying air pressure to at least one rear brake;
• at least one front modulator for controlling the air pressure provided to the front air chambers, and at least one rear modulator for controlling the air pressure provided to the rear air chambers;
• a dual brake cylinder connected in a pneumatic circuit with the air tanks and the front and rear air chambers;
• at least one front release valve, and at least one rear release valve connected via the pneumatic circuit between the dual brake cylinder and the front and rear air chambers respectively;
• a first solenoid valve connected via the pneumatic circuit with the dual brake cylinder and the front release valve;
• a second solenoid valve connected via the pneumatic circuit with the dual brake cylinder and the rear release valve;
• wheel speed sensors for sensing a rotational speed for each of the vehicle's front and rear wheels;
• an anti-lock brake system (ABS) control unit for controlling anti-lock and anti-slip brake systems after analyzing the rotational speed of each wheel as detected by the wheel speed sensors;
• the front and rear modulators being responsive to signals from the ABS control unit for regulating air pressure to the respective front and rear air chambers;
• a slope start control unit for integrally controlling an auxiliary slope start function and auxiliary parking function after analyzing data from a plurality of sensors provided on the vehicle;
• the first and second solenoid valves executing the slope start control function by adjusting the air pressure transmitted to the front and rear release valves, according to a control signal from the slope start control unit;
• and
• a third solenoid valve connected, via the pneumatic circuit, with the air tank and the front and rear release valves for executing the auxiliary parking control by adjusting the front and rear release valves according to a control signal from the slope start control unit.

An air-over-hydraulic brake system for a plurality of brakes on a vehicle, the system comprising:

• at least one air tank for supplying air pressure to the air-over-hydraulic brake system;
• a plurality of master cylinders for connection via a hydraulic circuit with a plurality of brakes;
• a dual brake cylinder for connection via a pneumatic circuit with each of the master cylinders, the dual brake cylinder receiving air pressure from the air tank and providing air pressure to each master cylinder, wherein each master cylinder generates hydraulic pressure for actuation of at least one of the brakes;
• at least one wheel speed sensor for sensing a rotational speed of at least one of the vehicle's wheels;
• an anti-lock brake system (ABS) control unit for controlling anti-lock and anti-slip brake systems after analyzing the rotational speed of a wheel as detected by the wheel speed sensors while braking force is generated by the dual brake cylinder, wherein the ABS system outputs an anti-lock control signal;
• a plurality of modulators for executing brake control, each modulator being connected via the pneumatic circuit with the air tank and one of the master cylinders via a relay valve, wherein the modulator affects brake control by modulating air pressure to a corresponding master cylinder according to the anti-lock control signal from the ABS control unit;
• a slope start control unit for integrally controlling an auxiliary slope start function and auxiliary parking function after analyzing data from a plurality of sensors provided on the vehicle;
• first and second solenoid valves connected via the pneumatic circuit between an output of the dual brake cylinder and the relay valve, wherein in response to the control signal from the slope start control unit, the solenoid valves control braking force by adjusting air pressure to the modulators;
• a third solenoid valve connected via the pneumatic circuit between the air tank and output side of the relay valve for adjusting the amount of air being provided to the relay valve according to a control signal from the slope start control unit.