A method for testing a pressure-medium-operated electronic brake system of a vehicle having a valve and sensor device including a control pressure inlet, a control pressure outlet, a plurality of valves selected from electrically activated inlet valves, outlet valves, redundancy valves, and pressure valves, an actual pressure sensor for measuring an actual control pressure, a setpoint pressure sensor for measuring a setpoint control pressure, and an electronic control unit, which has a signal-conducting connection to the electrically activated valves and pressure sensors, for receiving pressure signals and actuating the electrically activated valves, includes testing the setpoint pressure sensor while the control unit is in a passive operating mode, passing the setpoint control pressure directly through to the control pressure outlet, measuring the actual pressure at the control pressure outlet using a sensor, and transmitting the measured value to the control unit for plausibility checking against the setpoint pressure measurement.

A system and method of controlling individual trailer brakes on a towed trailer supporting numerous fault tolerant behaviors including activating each operational brake when a brake is shorted. System operates in multiple modes where it operates with traditional brake controllers, operates in a degraded braking mode without a brake controller and in the preferred mode it retrieves vehicle information from tow vehicle and then communicates with a brake actuator controller over the trailer brake wire. When braking system includes wheel sensors traditional antilock releases are provided and unlike other braking systems this brake actuator controller can maintain wheel speeds below the trailer speed reducing or eliminating periodic wheel releases. System also diagnoses the mechanical operation of the trailer brakes including; identifying when brake adjustment is required, when brake friction surfaces are degrading, as well as diagnosing sensors, braking signals and brake actuator interfaces.

A differentially steered vehicle includes brakes on the powered wheels which are applied via a controller according to different methods to inhibit freewheeling during turns and improve steering responsiveness and stability. The methods include applying braking force to the wheel on the inside of a turn in response to the rate of turn as indicated by the position of the steering control, to the pressure differential across the hydraulic motors driving the wheels and the rotational speed of the wheels.

According to at least one embodiment, the present disclosure provides a method of controlling a brake of a vehicle, the method comprising: a process of determining a pressure difference between channel pressure, which is determined by hydraulic pressure of the wheel brake, and required braking pressure by means of the controller; a process of opening the control valve by means of the controller when the channel pressure is larger than the required braking pressure; and a process of controlling the control valve on the basis of the difference between the required braking pressure and the channel pressure.

In order to detect air in a brake master cylinder within a hydraulic power brake system, a brake master cylinder pressure on actuation of the brake master cylinder is compared with a comparison pressure which prevails in the brake master cylinder when it is air-free. For bleeding, brake fluid is conveyed with a power brake pressure generator through the in this case non-actuated brake master cylinder into a pressureless brake fluid reservoir, where air escapes from the brake fluid.

Accurately controlling pressing thrust regardless of an individual difference and a use situation of a brake apparatus, and the like are set forth herein. The present invention controls a motor that applies thrust to a piston that presses a brake pad, in a current variation period before an idling current period, a variation in the current and the voltage or a variation in a function including the current and the voltage in the idling current period is computed as a plurality of prospective values. At a predetermined time T0 during the current variation period, one of the plurality of prospective values is selected on the basis of the current and the voltage, and on the basis of the variation in the current and the voltage or the function related to the selected prospective value, a characteristic parameter of the motor is computed to compute a stop current of the motor.

The invention relates to an electromagnetic valve device having an armature (18) which is moveable in an axial direction in a valve housing (10) in response to energizing of a stationary coil (12), and which is designed to interact with a first valve seat (22) associated with a fluid inlet connection (26) of the valve housing, a first fluid flow path (36) being formed in the valve housing such that fluid flowing through the opened first valve seat can flow in order to actuate a plunger (32) moveable relative to the armature (18) and to which a preloading force is applied, the actuation causing a second valve seat (43) interacting with the plunger (32) to be opened to produce a fluid connection to a fluid working connection (42) of the valve housing, and the valve housing having a fastening structure (44, 46) in the form of at least one hole extending at an angle to the axial direction, the fluid inlet connection (26) and the working connection (42) being formed on the same axial side of the valve housing in relation to the structure means.

The present disclosure relates to a control method of a brake system including a reservoir in which oil is stored, wherein the control method includes detecting a first level of a liquid level of oil stored in the reservoir, detecting a second level of the liquid level of oil stored in the reservoir, determining a decrease trend of an oil amount stored in the reservoir based on a time point when the first level is detected and a time point when the second level is detected, and limiting at least one additional function based on the decrease trend of the oil amount.

A brake control device (10) for delivering air under controlled pressure to a pneumatic brake actuator (BA), comprising an inlet port (51) coupled to a compressed air supply circuit, a working port (54) coupled to a service brake chamber (C2) of the brake actuator (BA), a venting port (56), first and second inlet solenoid valves (31, 32) for selectively connecting inlet port(s) to the working port, first and second outlet solenoid valves (41, 42) for selectively connecting the working port to venting port(s), a biased check valve (12), for coupling the working port to venting port(s), the brake control unit device further comprising first and second local electronic control units (21, 22) for controlling independently first and second inlet solenoid valves and first and second outlet solenoid valves.

A piston-cylinder unit includes a piston delimiting at least one working chamber, in which a first seal for sealing at least one first working chamber is arranged either between the piston and cylinder or between a plunger connected to the piston and the cylinder. A second seal is arranged between the first seal and the first working chamber, and the piston-cylinder unit further includes a first channel arranged in the wall of the cylinder or in the piston, which joins the first seal and the second seal in the inner chamber of the cylinder. The first channel and/or a hydraulic line connected thereto may have a throttle device and/or a valve device. An electronic control and regulating device may have a diagnosis or monitoring function for a possible defect or failure of a seal. Multiple hydraulic devices may have such piston-cylinder units and respective control and such regulating devices.