摘要:
Hydraulic or electro-hydraulic braking systems which include at least one wheel braking device and micro-machined technology, such as microvalves, are described herein. The use of the microvalves helps to eliminate audible noise produced in the hydraulic systems as well as allows for reduced package size of the system. In particular, many of the braking systems described herein have Anti-lock Braking System (ABS) capabilities, and as such employ apply microvalves, dump microvalves and changeover microvalves. The microvalves may be digitally or proportionally controlled for selectively controlling the pressure supplied to the wheel brake cylinders.
摘要:
Hydraulic or electro-hydraulic braking systems which include at least one wheel braking device and micro-machined technology, such as microvalves, are described herein. The use of the microvalves helps to eliminate audible noise produced in the hydraulic systems as well as allows for reduced package size of the system. In particular, many of the braking systems described herein have Anti-lock Braking System (ABS) capabilities, and as such employ apply microvalves, dump microvalves and changeover microvalves. The microvalves may be digitally or proportionally controlled for selectively controlling the pressure supplied to the wheel brake cylinders.
摘要:
A vehicular anti-skid control apparatus comprises a differential pressure detector for detecting the pressure difference inside brake lines of separate brake channels, a brake failure detector for detecting failure in one of the brake channels based on the anti-skid control state of each brake channel, a brake failure evaluator for evaluating failure of the brake system based on both output signals of the differential pressure detector and brake failure detector wherein the anti-skid control method is changed from normal anti-skid control to a particular anti-skid control when a brake failure occurs.
摘要:
This invention relates to a hydraulic brake system for automotive vehicle with a master cylinder (2) and with a hydraulic power booster (1) connected upstream of the master cylinder (2) and having a pressure chamber (4) in which an auxiliary pressure depending on the actuating force (F) may be modulated via a pedal-operable brake valve (7). Wheel brakes (51, 53) of a first brake circuit are connected at the pressure chamber (4), wheel brakes (50, 52) of a second brake circuit being connected at the master cylinder (2). The braking pressure active in the wheel brakes (50 through 53) is controllable by valve members (39, 54 through 59) controllable in dependence on the slip. In case of control, a hydraulic communication will be established between the pressure chamber (4) of a hydraulic power booster (1) and the master cylinder. It is suggested to provide a valve device (49) which in case of control may be switched over and by means of which two wheel brakes (52, 53) of one axle may be connected with each other. The wheel brakes of one brake circuit each are arranged at the vehicle so as to diagonally oppose each other. By using such means a hydraulic brake system is realizable which in the case of normal brake actions has a diagonal brake circuit allotment and in which in case of control caused by slip detection two wheel brakes (52, 53) of one vehicle axle are connected with each other, the brake system thus working with a Y-brake circuit allotment during brake slip control.
摘要:
In a road vehicle braking system incorporating wheel slide protection, sensing apparatus provides a signal representing the rotational deceleration of a vehicle wheel, and brake control apparatus responsive to said signal releases the brakes from the wheel when the magnitude of the signal exceeds a predetermined value. The power for the system is derived from a battery on the vehicle by way of switching apparatus, and fault sensing means is provided for turning the switching means off so that the system reverts to normal braking when a given fault occurs in the system.
摘要:
This invention relates to an antiskid braking system for automotive vehicles, wherein the fluid supply connection provided between a variable fluid braking pressure control source and a set of fluid pressure actuated brake motors is controlled by fluid pressure modulating valve means actuated by output control signals generated by an antiskid unit in response to a skidding condition of the brake vehicle. The fluid supply connection is provided with a restricted area fluid passage disposed between said fluid source and said modulating valve means so as to substantially limit the fluid flow rate to said brake motors upon opening of said fluid supply connection, and thereby to dampen the build-up in pressure to the brake motors.
摘要:
A brake force control device for a vehicle includes a master cylinder for being operated by an operating member of the vehicle, a wheel brake for being mounted on a vehicle wheel which is connected to the master cylinder through a conduit, a pressure control chamber connected to the wheel brake, a displacement actuator which varies a capacity of the pressure control chamber and a control unit which controls the displacement actuator. The displacement actuator includes a plunger which varies a capacity of the pressure control chamber, a drive unit which drives the plunger, a first valve which closes the conduit when the plunger is operated to decrease the capacity of the pressure control chamber and which opens the conduit when the first valve receives a brake pressure from the master cylinder which is larger than that in the pressure control chamber with a predetermined value, and a second valve which closes the conduit when the plunger is operated to increase the capacity of the pressure control chamber and which opens the conduit when the brake pressure in the pressure control chamber is larger than that in the master cylinder with a predetermined value.
摘要:
The yaw moment reducing device comprises wheel speed sensors for detecting the speeds of the right and left wheels, an acceleration calculation device for calculating accelerations of the right and left wheels based on the speed of the right and left wheels, a substraction device for subtracting the difference in accelerations between the right and left wheels, a braking control device for controlling the braking force based on the difference of the accelerations, and a brake pressure modulating device for modulating the brake pressure which is supplied to each wheel. The wheel speeds of each wheel are detected by the wheel speed sensors. The acceleration calculation device calculates the accelerations of each wheel while the substraction device provides the difference in accelerations between the right and left wheels. The yaw moment is in response to the difference of the acceleration between the right and left wheels. In other words, the yaw moment can be presumed by the difference of the acceleration between the right and left wheels. The brake pressure modulating device modulates the brake pressure which is supplied to each wheel based on the calculation result of the braking control devices. Thus, the yaw moment can be controlled.
摘要:
The invention is directed to an arrangement for controlling a braking force applied to each of road wheels of a rear drive vehicle depending upon a braking condition, with a hydraulic braking pressure supplied to each of wheel brake cylinders through pressure control valves respectively. The pressure control valves are controlled by the braking force controller into which output signals of wheel speed sensors are fed. In a first determination unit, it is determined if at least one of the front road wheels is on a road surface of a coefficient of friction lower than a predetermined value, and determined if the front wheel speed of one of the front road wheels has reached to a peak wheel speed. And, in a second determination unit, it is determined if a difference between the front wheel speed and rear wheel speed is less than a predetermined speed. When it is determined that at least one of the front road wheels is on the road surface of the low coefficient of friction and the front wheel speed has reached to the peak wheel speed, and that the difference between the front and rear wheel speeds is less than the predetermined speed, an asynchronous control unit prohibits the braking force controller from synchronously controlling the braking force applied to the front road wheels.
摘要:
The circuit comprises a primary circuit (2) feeding brake motors (5) and (7) and a secondary circuit (3) feeding a brake motor (9). In normal operation a valve (11) isolates the brake motor (22) from the secondary circuit (3). The pressure in the primary circuit then controls the pressure prevailing in the brake motor (22) with the aid of a pressure balancing device (25) installed between the feed lines of the brake motors (7 and 22). In the event of the failure of the primary circuit (2) the valve (11) establishes communication between the brake motor (22) and the secondary circuit (3) to effect the braking of the wheel associated with the brake motor despite the fact that the balancing device (25) is put out of action in this situation. Application to a brake circuit equipped with an anti-wheel-lock device.