Abstract: Disclosed herein an electronic brake system includes a hydraulic pressure supply device including a first pressure chamber and a second pressure chamber partitioned by a hydraulic piston, and a hydraulic control unit, wherein the hydraulic control unit comprises a first hydraulic flow path connecting the first pressure chamber and one of the first and second hydraulic circuits, a second hydraulic flow path branched from the first hydraulic flow path to connect to the other one of the first and second hydraulic circuits, a third hydraulic flow path branched from the first hydraulic flow path on upstream side of a branch point of the second hydraulic flow path to connect the second pressure chamber, and a fourth hydraulic flow path branched from the first hydraulic flow path on upstream side of a branch point of the third hydraulic flow path to connect the third hydraulic flow path.

Abstract: A method for controlling an electronically slip-controllable power braking system of a motor vehicle. Power braking systems are equipped with a plunger unit, which includes a plunger piston accommodated in a plunger cylinder and delimiting a working chamber, for generating brake pressure in brake circuits. This plunger piston is actuatable by an electronically activatable drive in a pressure buildup direction or in the opposing spatial direction thereto in a pressure reducing direction. A time-limited drive of the plunger piston takes place in the pressure reducing direction as soon as an actual brake pressure generated by the plunger unit has reached a predefinable setpoint brake pressure and a decoupling of a wheel brake and the plunger unit from an associated brake circuit has taken place.

Abstract: A control device and a method for operating a hydraulic braking system of a vehicle, a volume supplementation in a motorized plunger device being effectuatable by moving a plunger of the motorized plunger device at a maximum movement speed by a maximum movement travel in a pressure reduction direction, at least one setpoint variable regarding the maximum movement speed and/or the maximum movement travel of the plunger during the subsequent volume supplementation being established, before the volume supplementation, with consideration of at least one provided variable regarding current driving situation information and/or surroundings information, and the motor of the motorized plunger device is activated during the subsequent volume supplementation with consideration of the at least one established setpoint variable.

Abstract: A hydraulic block for a hydraulic power unit of a hydraulic vehicle brake system includes a main brake cylinder bore and an intake that are integrated to form a pedal travel simulator.

Abstract: An electronic brake system may be capable of performing braking operation according to a pedal effort of a driver even when the brake system operates abnormally as well as simplifying a configuration thereof by minimizing the number of valves for controlling a flow of oil pressure and precisely controlling pressure therein.

Abstract: The present invention relates to a pressure generator for a hydraulic vehicle brake system for the regulated generation of a hydraulic brake pressure in a brake circuit, the pressure generator having a multiple-piston pump for delivering a brake fluid with at least two pump pistons and associated pressure chambers, on which the pump pistons act, an actuator for actuating the multiple-piston pump, and a fluid feed line which extends to the pressure chambers and is configured for connection to a storage container, in which a hydraulic fluid is stored. At least one valve is arranged in the fluid feed line and divides the latter into a first section which is arranged upstream of the valve and into a second section which is arranged downstream of the valve, the valve being configured to optionally at least partly shut off or open the second section of the fluid feed line and therefore to control the fluid supply of at least one pressure chamber.

Abstract: A braking system having a master cylinder to which wheel brake circuits (I, II) can be connected, a first piston coupled to a brake pedal, a second piston by means of which the master cylinder is actuated, a third piston actuated by the first piston and connected in a force transmitting fashion to the second piston, a simulation device which gives the driver of the vehicle a pedal sensation, an intermediate space between the second piston and third piston, a pressure generating device which controls the pressure in the intermediate space, a pressure medium reservoir vessel which is under atmospheric pressure and which can be connected hydraulically to the intermediate space, and means for electrically controlling the pressure in the intermediate space.

Abstract: When an element of the electro-hydraulic brake circuit (1) is malfunctioning, a master cylinder (2) can brake the vehicle. A brake actuation simulator (8) is then disconnected from the master cylinder (2) by means of an O-ring gasket (22) after the gasket has been compressed between a groove (16) in a secondary piston (11) and a bore (24) in the master cylinder. In order to prevent the gasket from being extruded from the groove during brake release (or brake pedal release) resulting from sudden braking, the invention makes provision for a pressure relief duct (32) to be provided inside the secondary piston. Extra pressure can then be discharged during brake release (or brake pedal release) through the brake release duct (32) from the inside of the chamber (30) of the simulator towards the primary chamber (10) of the master cylinder.

Abstract: A master cylinder apparatus for a BBW system is provided, which enables accurate detection of a piston stroke without substantial increase in the size of a master cylinder. A master cylinder apparatus includes a master cylinder adapted to be connected to wheel cylinders through fail-safe valves, a stroke simulator for ensuring a desired stroke of a brake pedal upon receiving a brake fluid introduced from a fluid pressure chamber in the master cylinder through a simulator passage, and an opening/closing device for opening and closing the simulator passage. A stroke sensor for detecting a stroke of a primary piston is formed by a rotation angle detector, a sensor arm having one end connected to a rotary shaft of the rotation angle detector and a sensor pin extending from the primary piston. Linear motion of the primary piston is converted to rotational motion through engagement between the sensor pin and the sensor arm and is transmitted to the rotation angle detector.

Abstract: A control valve (10) having a plunger (64) with a stem having a flange defined by a first diameter (66) loosely located in a first diameter (58) of a bearing (50) and a second diameter (68) sealingly located in a second diameter (56) of the bearing (50). A space between the flange and the bearing (50) defining a dampening chamber (82) such that on movement of plunger (64) toward an actuation chamber (54), fluid is drawing through a controlled flow path (x) into the dampening chamber (82). Under certain operational conditions, fluid pressure in the actuation chamber (54) maybe subjected to oscillation and the fluid in the dampening chamber (82) cancels the effect to the oscillation such that plunger (64) remains in a substantially stationary position corresponding to an input force applied thereto to effect a brake application.

Abstract: A vehicle hydraulic system is disclosed comprising a hydraulic fluid reservoir; a pressure force supplying pressurized hydraulic fluid to a discharge header; a fluid conduit between the discharge header and the reservoir; a back pressure valve operative in the fluid conduit to maintain a desired pressure in the discharge header; and a vehicle braking system having a hydraulically operated boost piston assembly for supplementing a force exerted by a vehicle operator to operate brakes of the vehicle braking system. The system further includes a boost pressure control valve responsive to an input from the vehicle operator for selectively directing pressured hydraulic fluid from the discharge header to the boost piston assembly and venting hydraulic fluid from the boost piston assembly to the reservoir.

Abstract: A master cylinder (32) in a vehicle hydraulic braking installation uhydraulic-fluid supply device for actuating wheel brake cylinders (20). The master cylinder (32) being isolated from the wheel brake cylinders (20) by at least one shut-off valve (30). The master cylinder (32) being associated with a simulator (46) having a piston (50) located in a simulator chamber (56). The piston (50) being subjected to fluid pressure of brake fluid from the master cylinder (32) and an elastic element (52). The master cylinder (32) being of the having a primary piston (44) and a secondary piston (60) slidably located in a bore (45) of a housing (48). Bore (45) has a peripheral groove (72) which is associated with a land (68) on the secondary piston (60) to allow communication with the simulator chamber (56) when the master cylinder (32) is in a positon of rest.

Abstract: A brake-pressure-transmitter arrangement (1) for a hydraulic motor-vehicle brake system, after an actuating force (F) has been introduced via an input member (brake pedal 2), by reduction in the volume of a hydraulic chamber (4) to be filled with brake fluid, provides a brake pressure at the output of the hydraulic chamber (4) for at least one wheel brake (3). In addition to the hydraulic chamber (4), there is a hydraulic chamber (6) for brake fluid, and the volume of this hydraulic chamber (6) is likewise reduced after introduction of the actuating force (F). To amplify the brake force, an output of this additional hydraulic chamber (6) is in fluid connection with the input side (10e) of a booster pump (10), which delivers brake fluid in the direction from the additional hydraulic chamber (6) to the at least one wheel brake (3).

Abstract: A plurality of electrical fluid pressure control valves or a plurality of groups each comprised of a plurality of electrical fluid pressure control valves are operatively associated with respective power supply replays. The electrical fluid pressure control valves and a plurality of electrical switch valves are connected in parallel to a power source. A plurality of failure sensors are associated with the respective electrical fluid pressure control valves or the respective groups so as to detect whether an electrical system failure in any one of the electrical fluid pressure control valves or the groups occurs. If occurs, failure control unit is operable to control a corresponding one of the power supply relays so as to cause a corresponding one of the electrical switch valves to selectively connect a corresponding one of the wheel cylinders to a master cylinder.

Abstract: A brake master cylinder (10) for a hydraulic vehicle brake system has a master cylinder housing (32) and at least one pressure chamber (40) designed therein. Connected to the pressure chamber (40) is a hydraulic fluid reservoir which, furthermore, is provided for connection to a precharge pump of a brake pressure regulating system. Moreover, the brake master cylinder (10) has a hydraulic fluid return connection (30) which makes a fluid connection between the delivery side of the precharge pump, the reservoir and the at least one pressure chamber (40). A throttle (60) is arranged in this liquid connection, said throttle not impeding a hydraulic fluid stream out of the reservoir into the at least one pressure chamber (40) and throttling a hydraulic fluid stream from the return connection (30) into the reservoir. The throttle (60) makes it possible to cause the precharge pump to act on the at least one pressure chamber (40), without an electromagnetic valve being interposed.

Abstract: A travel simulator having a progressive pedal characteristic to be in operation in a power-actuated service brake. The hydraulic brake system has a valve assembly for the switching of the brake system into operation as either a service brake or as an emergency brake. The master cylinder has a pressure fluid reservoir, two pressure chambers, and an intermediate piston as well. The intermediate piston is supported on a travel simulator spring. When the service brake is in operation, pressure fluid can be diverted from the second pressure chamber into the reservoir, and the intermediate piston is moved against the resistance of the spring. When the emergency brake is in operation, both pressure chambers communicate with one another so that the intermediate piston is pressure balanced. When the pedal is actuated, pressure fluid is expelled from the first pressure chamber. The intermediate piston is not subject to any motion during an emergency brake operation. The brake system is for use in road vehicles.

Abstract: A brake control system for an automotive vehicle has an improved hydraulic circuit network which is capable of performing pressure boosting operation for a pressure supplied from a master cylinder, as well as anti-skid brake control operation and traction control operation. The system includes a valve device for selectively establishing and blocking fluid communication between master cylinder and wheel cylinder. The valve device is generally responsive to the fluid pressure supplied from the master cylinder to enter into pressure boosting mode in response to increase in the fluid pressure from the master cylinder across a predetermined value. An electronically operable boost control device cooperates with the valve device for varying pressure boosting magnitude depending upon vehicle driving condition.

Abstract: The brake system has an apparatus for traction control having a pressure generator. The pressure generator has a longitudinally displaceable cylinder for receiving brake fluid. The cylinder is connected by means of a valve to a pressure course between a master brake cylinder and a wheel brake cylinder. An actuating element is provided for closing and opening the pressure course to the master brake cylinder as a function of the cylinder position. The actuating element, extending coaxially between the cylinder and the valve comprises a tube and furnishes hydraulic communication between the cylinder and the valve. If excessive drive slip occurs, brake fluid can be positively displaced out of the cylinder by longitudinal displacement thereof, and brake pressure can be generated in the wheel brake cylinder. The actuating element assumes a piston function, which enables a structure of the cylinder having a smaller diameter and a long stroke. This makes for more accurate adjustment of the brake pressure.

Abstract: A brake pressure control device introduces pump pressure which is produced by a pump (16) into piping which connects a master cylinder (4) and wheel brakes (11, 11', 12, 12'). The increase, decrease and retention of the wheel brake pressure are effected by utilizing the pump pressure. Absorbers (19, 19') which consume hydraulic fluid are installed in branches from piping which connects the master cylinder (4) and the wheel brakes (11, 11', 12, 12'). 4-port 2-position control valves (5, 5') are installed in the hydraulic passages which connect the master cylinder (4) and the absorbers (19, 19') and at the inlet port for the pump pressure and at the outlet port to the absorbers (19, 19').

Abstract: The hydraulic booster device controls a ball valve (25) to establish a communication between a source of fluid at high pressure (35) and a braking circuit (29) during a normal braking. In the event of failure of the high pressure source (35), the braking is ensured by pressurizing of the fluid contained in a chamber (33) by a piston mechanism (20), and transfer of this fluid into the circuit (29). An additional useful volume of brake fluid is supplied to the circuit (29) by fluid expelled from the chamber (11) by the penetration of the plunger (5) into this chamber, after the piston mechanism (20) has come to a stop against the end fitting (3). Application to a hydraulic braking circuit for automobile vehicle.

Abstract: Hydraulic booster device intended to be arranged in parallel with a primary actuation circuit between an actuator mechanism and a receiver, the device comprising an electromagnetic valve mechanism (10) arranged between an actuator (12) and a pressure-fluid source (16), the actuator (12) comprising a piston means (56, 66, 92) displaceable under the effect of the pressure-fluid and intended to actuate the receiver independently in response to an electrical control signal supplied to the valve mechanism (10).

Abstract: Hydraulic booster comprising a housing provided with a bore inside which there is slidably mounted two pistons each associated with a respective pressure chamber intended to be connected to a respective brake circuit; an actuating piston slidably mounted inside the bore and intended to be displaced by a brake pedal, displacement of the actuating piston being capable of causing displacement of the two pistons; and two valve mechanisms each associated with a respective brake circuit and intended to control the flow of pressurized fluid from a respective source to the brake circuit, characterized in that the two valve mechanisms are arranged parallel to the bore and are intended to be actuated simultaneously by the actuating piston.

Abstract: A piston in a first cylinder is driven as a piezoelectric element group, which includes a plurality of laminar piezoelectric elements stacked in layers, extends or contracts. A second cylinder is formed so as to connect with a first fluid pressure chamber which is defined in the first cylinder by the piston. A piston-shaped valve member is disposed in the second cylinder. The valve member is urged toward the first fluid pressure chamber by a spring. The first fluid pressure chamber is supplied with a fluid whose pressure is set by means of a selector valve. When the selector valve is closed, the fluid pressure chamber is defined as an independent compartment. In this state, high voltage is applied to the piezoelectric element group to elongate it, thereby driving the piston. Thus, the valve member is actuated by the fluid pressure inside the first fluid pressure chamber, and a fluid passage is opened and closed by the valve member.

Abstract: Hydraulic assistance device comprising a housing (10) provided with a bore (12) in which a piston mechanism (30, 42) is slidably mounted, which mechanism is displaceable by a brake pedal between a first position linking a first chamber (38, 56), connected to a brake circuit (60), with a low-pressure reservoir and isolating this chamber (38, 56) from a high-pressure fluid source (66), and a second position isolating the chamber (38, 56) from the low-pressure reservoir and linking it with the high-pressure source (66), the piston mechanism (30, 42) being displaceable by the brake pedal in the event of failure of the high-pressure circuit (66) thereby producing pressure increase in a second chamber (69) connected to the brake circuit (60), characterized in that the working area of the piston mechanism (30, 42) is equal to the cross-section of the bore (12).

Abstract: The hydraulic assistance device incorporates a casing (10) enclosing first and second sliding components (18, 20) arranged in line, the first component (18) being capable of being displaced under the effect of the displacement of a pushrod (34) and the second component being capable of being displaced through the intermediary of a hydrostatic connection, and associated with each component (18, 20) is a valve mechanism (36, 46) in a respective hydraulic circuit between a source of fluid under pressure and a respective braking circuit (I, II), characterized in that the first and second components (18, 20) each constitute a piston sliding in a bore (14) in the casing (10) and each encloses a valve assembly (26, 40; 36, 46) each controlled by a plunger (30, 44), the plunger (30) of the first valve assembly (26, 36) being actuated by the pushrod (34), and the plunger (44) of the second valve assembly (40, 46) being actuated by the hydrostatic connection between the two pistons (18, 20).

Abstract: An automobile braking force control apparatus controls braking forces on some or all of the wheels individually or in groups. The operating force from a brake pedal (2) is converted into a hydraulic pressure by a master cylinder (3). This converted hydraulic pressure acts on the pistons of actuators (7a, 7b, 7c, 7d) disposed in operating channels (6a, 6b, 6c, 6d) leading to some or all of the wheels taken individually or in groups. The braking force on the wheels vary with the movements of the pistons. Auxiliary power circuits (8a, 8b, 8c, 8d, 9a, 9b, 9c, 9d) are provided for enabling hydraulic pressure from an auxiliary power source (12) to act on the pistons of the actuators (7a, 7b, 7c, 7d). Control valves (10a, 10b, 10c, 10d) controled by an electronic control device (13) are disposed in auxiliary power circuits.

Abstract: Hydraulic assistance device incorporating a casing provided with a bore in which a first piston is mounted so as to slide, the piston being able to move under the effect of a brake pedal between a first position, isolating a first chamber which is joined to the brakes of the vehicle, from a source of high pressure fluid, and a second position, causing the first chamber to communicate with the high pressure source, the device also incorporating a second chamber formed in the casing, a passage joining the first and second chambers and a valve mechanism in the passage in such a way that the passage is normally closed, under the effect of the pressure in the second chamber, characterized in that the device incorporates a second passage, causing the second chamber to communicate with a low pressure reservoir, and a second valve mechanism in the passage, the valve mechanism being sensitive to the pressures in the first and second chambers in such a way that the passage normally remains closed during the operation o

Abstract: Hydraulic assistance device of the mixed hydrodynamic/hydrostatic type incorporating a body (10) in which a first piston (18) is slideably mounted and moveable between a first position allowing the communication of a first chamber (53), joined to a braking circuit, to a reservoir (12), and isolating this chamber (53) from a source of high pressure fluid (86), and a second position isolating the chamber (53) from the reservoir (12) and connecting it with the source (86); a second chamber (30) in the body (10) connected by a passage (90) to the brakes (66), and valve mechanism (92) normally closing the passage (90) and sensitive to the pressure in the chamber (30) so that, when the latter pressure reaches a value which is greater than that existing in the first chamber (53), the valve mechanism (92) opens allowing fluid to flow between the second chamber (30) and the brakes (66).

Abstract: An arrangement for controlling the supply of pressurized hydraulic fluid from a master cylinder and from a pressure source into hydraulic circuits leading to wheel brake actuating cylinders includes a valve device including a control piston acted upon by a spring-loaded auxiliary piston in one direction and by the pressure in a return conduit in the opposite direction. Upon brake pedal depression, hydraulic fluid pressure from the pressure source acts on the auxiliary piston in opposition to the spring force so that the auxiliary piston ceases to act on the control piston. Then, as hydraulic fluid is discharged from the brake actuating cylinders during antiskid control action, pressure builds up in the return conduit and propagates to the control piston to move the same into its open position in which it admits pressurized fluid from the pressure source to check valves which are acted upon in opposition to their opening by the tandem master cylinder pressures.

Abstract: A closed-center hydraulic servo apparatus (10) includes a closed-center valve device (112) which is coupled to an input member (60) to control the communication of fluid among a fluid pressure source (12,14), a fluid reservoir (36), and a fluid pressure responsive device (a vehicle brake) (16) in response to movement of the input member (60). The coupling (158, 160) between the closed-center valve device (112) and the input member (60) provides a movement ratio therebetween which is greater than unity. As a result, the inherent deadband (D) of the closed-center valve device (112) is reduced by the inverse of the movement ratio to a level (d) which is sensible to an operator at the input member (60).

Abstract: A method and apparatus for treating hot exhaust gas to purify the gas and to recover the heat values therein includes removing particulate matter from the gas, purifying the gas by subliming or "freezing out" harmful, less volatile components and discharging the more volatile components as purified gas. The sublimed or "frozen out" components are collected and neutralized or utilized. The heat values may be recovered prior or subsequent to purifying, such as by spraying a power fluid into the gas to cool and increase the volume of the gas and then expanding the gas in an expansion turbine to further cool the gas and to produce shaft work. Alternatively, the heat values may be recovered from purified, hot gas by transferring the heat energy of the gas to a power fluid which operates in a Rankine cycle external combustion engine to do shaft work.

Abstract: For the hydraulic brake system of a vehicle such as a farm or industrial tractor having brakes on the right and left rear wheels for both braking and steering, flow control means operatively interconnecting a source of hydraulic pressure available when the vehicle is operating, a hydraulic fluid reservoir and a manually actuated brake applicator means such as a brake pedal, so as to provide power braking. The flow control means also provides for manual braking when hydraulic pressure is not available. A separate relatively large fill piston and small pressurizing piston used in manual braking are in combination with the power brake valve. An unloading valve is provided for cooperation with the fill piston during both the power and manual modes.

Abstract: A hydraulic brake force-multiplying device includes a body, an output member fitted slidably in the body, a working chamber defined between the output member and the body, a pressure chamber defined in the body and receiving pressure fluid introduced from a source of pressure fluid, a valve seat member positioned in the pressure chamber and urged against the body under fluid pressure of the pressure chamber, a rod member provided integrally with the valve seat member and extending to the interior of the working chamber, a guide bore extending through the rod member axially, a valve stem having a valve portion adapted to cooperate with a valve seat of the valve seat member, thereby forming a valve mechanism in combination with the valve seat, and being sealingly and slidably fitted in the guide bore, an input shaft provided in the body adjacent to one end of the valve stem remote from the working chamber, an intermediate chamber defined between the input shaft and the valve stem and adapted to be communicated