Vehicle braking system capable of preventing rock-back motion of driver/passenger upon vehicle stopping

A braking system for a motor vehicle, comprising:

• a hydraulically operated brake device having a brake operating member, and wheel cylinders provided on wheels of the vehicle for braking the wheels with braking pressures corresponding to an operation of the brake operating member;
• vehicle speed detecting means for detecting a running speed of the vehicle;
• deceleration detecting means for detecting a deceleration rate of the vehicle;
• pressure-decrease control means for effecting an anti-rock-back operation to lower said braking pressures of said wheel cylinders, in a plurality of steps, for a controlled time duration for each of said steps, when the detected running speed of the vehicle falls below a predetermined reference value;
• and
• decrease-time determining means for determining said controlled time duration such that said time duration decreases with a decrease in the detected deceleration of the vehicle before said anti-rock-back operation is started by said pressure-decrease control means.

A braking system for a motor vehicle, comprising:

• a hydraulically operated brake device having a brake operating member, and wheel cylinders provided on wheels of the vehicle for braking the wheels with braking pressures corresponding to an operation of the brake operating member;
• vehicle speed detecting means for detecting a running speed of the vehicle;
• deceleration detecting means for detecting a deceleration rate of the vehicle;
• pressure-decrease control means for effecting an anti-rock-back operation to lower said braking pressures of said wheel cylinders in a plurality of steps, when the detected running speed of the vehicle falls below a controlled reference value;
• and
• reference vehicle speed determining means for determining said controlled reference value of said running speed of the vehicle such that said reference value decreases with a decrease in the deceleration rate of the vehicle detected by said deceleration detecting means before said anti-rock-back operation is started by said pressure-decrease control means.

A braking system for a motor vehicle, comprising:

• a hydraulically operated brake device having a brake operating member, and wheel cylinders provided on wheels of the vehicle for braking the wheels with braking pressures corresponding an operation of the brake operating member;
• vehicle speed detecting means for detecting a running speed of the vehicle;
• a solenoid-operated pressure control valve device adapted to achieve a primary control operation which consists of at least one of an anti-lock operation to prevent an excessive amount of slip of said wheels of the vehicle during brake application by said hydraulically operated brake device, a traction control operation to prevent an excessive amount of slip of said wheels during acceleration of the vehicle, and a braking effect control operation to provide a braking effect which is predetermined depending upon an operation of said brake operating member, said pressure control valve device being operable between a pressure-increase position for feeding a brake fluid into said wheel cylinders to increase said braking pressures, and a pressure-decrease position for discharging the brake fluid from said wheel cylinders to decrease said braking pressures;
• a solenoid-operated flow restrictor device disposed in a fluid passage through which the brake fluid is discharged from said wheel cylinders, with said pressure control valve device placed in said pressure-decrease position, said flow restrictor device being operable between an operated position in which a discharge flow of the brake fluid from said wheel cylinders is restricted to a value lower than that during said primary control operation of said solenoid-operated pressure control valve, and a non-operated position in which said discharge flow is not restricted;
• and
• changeover means for operating said solenoid-operated pressure control valve to said pressure-decrease position, and operating said solenoid-operated flow restrictor device to said operated position, when the detected running speed of the vehicle falls below a predetermined reference value, whereby said braking pressures of said wheel cylinders are lowered to reduce an amount of rock-back of a driver and a passenger of the vehicle upon stopping of the vehicle.

A braking system for a motor vehicle, comprising:

• a hydraulically operated brake device having a brake operating member, and wheel cylinders provided on wheels of the vehicle for braking the wheels with braking pressures corresponding an operation of the brake operating member;
• vehicle speed detecting means for detecting a running speed of the vehicle;
• stop control means for effecting an anti-rock-back operation to lower said braking pressures of said wheel cylinders when the detected running speed of the vehicle falls below a predetermined reference value, and thereby reducing an amount of rock-back of a driver and a passenger of the vehicle upon stopping of the vehicle;
• braking condition determining means for determining whether said hydraulically operated brake device is activated for a normal braking operation, or for an emergency braking operation;
• and
• inhibiting means for inhibiting said stop control means from operating to effect said anti-rock-back operation, if said braking condition determining means determines that the brake device has been activated for said emergency braking operation.

A braking system for a motor vehicle, comprising:

• a hydraulically operated brake device having a brake operating member, and wheel cylinders provided on wheels of the vehicle for braking the wheels with braking pressures corresponding an operation of the brake operating member;
• vehicle speed detecting means for detecting a running speed of the vehicle;
• pressure detecting means for detecting said braking pressures of said wheel cylinders;
• pressure-decrease control means for effecting an anti-rock-back operation to lower said braking pressures of said wheel cylinders, in a plurality of steps, for a controlled time duration for each of said plurality of steps, when the detected running speed of the vehicle falls below a predetermined reference value;
• and
• decrease-time determining means for determining said controlled time duration such that said time duration increases with an increase in said braking pressures detected by said pressure detecting means before said anti-rock-back operation is started by said pressure-decrease control means.