Abstract: Hydraulic pressure control apparatus including a hydraulic pressure source device operable according to a control amount, to generate an output pressure thereof on the basis of a fluid pressure corresponding to an operating force of a manually operable operating member, and on the basis of a control pressure controlled by a pressure control actuator according to a control amount, and further including an actuator control device including a final-control-value determining portion operable to determine a final value of the control amount, which is used to control the pressure control actuator, and wherein the final-control-value determining portion determines the final value on the basis of at least two provisional control values selected from (a) at least one first provisional control amount each determined by at least one physical quantity including at least one of (i) an operating-state value representative of an operating state of the operating member and (ii) the output pressure, and (b) at least one secon
Abstract: A hydraulic pressure brake device for a vehicle includes a first piston outputting brake pressure generated in a first pressure chamber and a second piston having a larger diameter than that of the first piston and provided rearward of the first piston and forming a second pressure chamber having a larger diameter than that of the first pressure chamber. The hydraulic pressure brake device further includes a valve device closing the second pressure chamber hydraulically when actuation of the first piston and the second piston is assisted by the assisting device and establishing hydraulic communication between the second pressure chamber and the reservoir when the assisting is not carried out. The first pressure chamber is connected with wheel cylinders provided on front wheels through a first hydraulic pressure system and the second pressure chamber is connected with wheel cylinders provided on rear wheels through a second hydraulic pressure system.
Abstract: Upon detection of a potential transition from a low mu road surface to a high mu road surface, a rear wheel anti-lock brake system generates one dump pulse to increase the braking effort of the controller rear wheel as a test of the road surface. If the wheel accelerates following the test pulse, the transition is false and the anti-lock brake system continues as before. If the wheel does not accelerate following the test pulse, the transition is true and the anti-lock brake system proceeds to increase the braking effort of the controlled wheel brake.
Abstract: In a rotary pump, an outer rotor and an inner rotor are assembled in a casing such that, when a clearance between an inner teeth portion of the outer rotor and an outer teeth portion of the inner rotor is substantially nullified at a first closed gap portion having a maximum volume formed between the inner teeth portion and the outer teeth portion, a clearance between the outer rotor and the casing on a side of the first closed gap portion and a clearance between the outer rotor and the casing on a side of a second closed gap portion having a minimum volume, become substantially an equivalent interval. As a result, the outer rotor and the casing can be brought into contact with each other on the side of the second closed gap portion rather than the central axis of the inner rotor. Even in a high pressure discharge operation, the outer rotor is not locked by being squeezed between the inner rotor and the casing.
Abstract: A braking system including a brake cylinder, a first hydraulic pressure source having a first pump device for pressurizing a working fluid, a second hydraulic pressure source operable in response to an operation of a brake operating member, to pressurize the fluid to a pressure higher than a value corresponding to an operating force of the brake operating member, and a brake-cylinder-pressure control device operable when the brake cylinder is disconnected from the second hydraulic pressure source, to control the pressure of the fluid pressurized by the first hydraulic pressure source, such that the fluid pressure in the brake cylinder is controlled to a value determined on the basis of the operating force, and wherein an emergency communication device is operated when at least one of the brake-cylinder-pressure control device and the first pump device fails to normally function, to hold the brake cylinder in communication with the second hydraulic pressure source.
Type:
Grant
Filed:
October 3, 2000
Date of Patent:
March 12, 2002
Assignees:
Toyota Jidosha Kabushiki Kaisha, Aisin Seiki Kabushiki Kaisha
Abstract: The present invention is directed to a front-rear braking force distribution control system for a vehicle. The system includes a wheel brake cylinders operatively associated with front and rear wheels of the vehicle, a pressure generator for pressurizing brake fluid in response to operation of a brake pedal to generate a hydraulic braking pressure and supply it to each of the wheel brake cylinders, and a pressure control device disposed between the pressure generator and the wheel brake cylinders for controlling the braking pressure in each of the wheel brake cylinders. A pressure sensor is provided for detecting the braking pressure generated by the pressure generator, and the detected braking pressure is compared with a predetermined threshold pressure.
Abstract: A braking apparatus for vehicles BU, in which plurality systems of individually separated brake fluid pressure passages BC(A), BC(B) are arranged, and each passage is provided with at least one brake fluid pressure retaining means RU(A), RU(B) for continuously retaining brake fluid pressure within a wheel cylinder WC(A), WC(B) arranged in the brake fluid pressure passage after a depression of a brake pedal BP is released and for releasing the retained brake fluid pressure in response to an increase of a starting driving force of the vehicle, wherein the release of the retained brake fluid pressure is carried out in a time differential manner at each brake fluid pressure retaining means.
Abstract: Disclosed herein is an automatically operated antiskid apparatus for automobile tires. The automatically operated antiskid apparatus includes an operating signal generating unit for transmitting an operating signal generated by a bar operating switch to positions in the vicinity of automotive wheels. A signal transmitting unit receives the operating signal from the operating signal generating unit and transmits the operating signal from a stationary automobile body to rotating wheel rims. An antiskid bar and antiskid bar operating unit receives the operating signal from the signal transmitting unit and operates antiskid bars embedded in tread portions of the tires.
Abstract: A brake system for vehicles, in particular for motor vehicles, has electrically controlled hydraulic final control elements, integrated in a hydraulic block; a pressure sensor with a plurality of pressure measuring elements for measuring the hydraulic pressure controlled by the individual final control elements; and a control circuit for controlling the final control elements. For the sake of simple and secure mounting of the hydraulic block, pressure sensor and control circuit, the control circuit and pressure sensor are accommodated in a common housing of an add-on electronic control unit (ECU), from whose underside the pressure measuring elements protrude with smaller-diameter plug-in tubes. When the add-on ECU and hydraulic block are installed, and that the housing is mounted on the hydraulic block and solidly joined to it by insertion of the plug-in tubes into the fluid conduits, present in the hydraulic block, in a fluid-tight manner.
Type:
Grant
Filed:
July 28, 2000
Date of Patent:
February 19, 2002
Assignee:
Robert Bosch GmbH
Inventors:
Ortwin Engfer, Werner Wilde, Herbert Keller
Abstract: A braking pressure control apparatus for a braking system having brake cylinders including a pressurizing device capable of pressurizing a working fluid and controlling a pressure of the pressurized fluid, a plurality of pressure control valve devices each of which is disposed between the pressurizing device and at least one of the brake cylinders and is operable to control flows of the fluid between the pressurizing device and the corresponding at least one brake cylinder, for thereby regulating the fluid pressure in the corresponding at least one brake cylinder, and a pressurizing-device control device operable to control the pressurizing device for controlling an output pressure of the pressurizing device on the basis of an operating state of each of the pressure control valve devices, which operating state determines the state of fluid flow between the pressurizing device and the corresponding at least one brake cylinder.
Abstract: In a brake apparatus of the present invention, as MCY pressure is developed by a master cylinder (MCY) 1 according to the forward movement of a primary inner piston 9, a pump of a braking force control device arranged between the MCY 1 and wheel cylinders (WCYs) sucks up hydraulic fluid from the MCY 1 to discharge the hydraulic fluid to the WCYs. Thus, WCY pressure controlled according to operational conditions of various modes is developed. The WCY pressure is supplied to a control pressure chamber 40 to act on a step 8e of a primary outer piston 8. The primary outer piston 8 moves relative to the primary inner piston 9 in such a manner that the force produced by the MCY pressure, the force produced by the WCY pressure, the spring force of a control spring 13, and the frictional force of fluid-tightly slidable portions of the primary outer piston 8 are balanced, whereby the pedal travel can remain the same as that in service braking mode.
Type:
Application
Filed:
April 19, 2001
Publication date:
February 7, 2002
Applicant:
BOSCH BRAKING SYSTEMS CO., LTD & DENSO CORPORATION
Abstract: Improving operating feelings and energy saving are aimed for a brake system of the type in which a predetermined differential pressure is produced between a master cylinder and wheel cylinders by a hydraulic pressure limit/changeover means during regenerative braking, and at the end of regenerative braking, the differential pressure is cancelled by increasing the pressure in the wheel cylinders with fluid sucked up from a reservoir for pressure increase by an electric pump. A reservoir for pressure increase, which is also used as a stroke simulator, is provided on the master cylinder side of the hydraulic pressure limit/changeover means, an on-off valve and a check valve are provided parallel to each other on the inlet side of the reservoir for pressure increase, so that the split point hydraulic pressure and the pressure-reducing ratio of a proportional pressure-reducing valve for supplying brake fluid toward the wheel cylinders during the initial period of braking can be brought unlimitedly close to zero.
Abstract: The invention relates to a brake system including a brake booster. A pneumatic pressure operated brake booster VBB or a liquid pressure operated brake booster includes a valve mechanism which is urged by a force of depression applied to a brake pedal BP to switch a flow path to cause the brake booster to develop an output which depends on the magnitude of the force of depression. A solenoid SOL urges the valve mechanism in the same direction as or in the opposite direction from the force of depression. A controller ECU is responsive to a braking effort increase/decrease demand signal to increase or decrease the urging force which is applied by the solenoid to the valve mechanism, thus increasing or decreasing the output from the brake booster. An output from the brake booster can be freely controlled independently from the force of depression applied to the brake pedal in response to a, braking effort increase/decrease demand.
Abstract: An apparatus and a method for controlling hydraulic pressure are provided, which has such advantages that a generation of peak pressure (shoot pressure ) can be lowered, mis-operation due to biting of particles can be reduced, or the cost thereof can be reduced.
Abstract: An automatic breaking system which functions by applying a controlled breaking pressure signal through a control valve to each of the four corners of an automotive vehicle in response to input and feedback signals. A centralized computer receives various signals generated by transducers positioned at various positions within the vehicle including at each of the four corners as well as input signals from the vehicle brake peddle. These signals are processed by the computer and then applied through a control system to a direct drive valve which meters the application of the fluid under pressure to the breaks located at each corner of the vehicle. Direct drive valve is a limited angle rotary to linear direct drive valve which includes a housing having a first bore longitudinally disposed therethrough and a second bore disposed transversely therethrough and intersecting the first bore. A valve spool is slidably disposed within a second bore for controlling the flow of fluid under pressure.
Abstract: A vehicle hydraulic brake apparatus includes a brake member, a master cylinder generating a brake hydraulic pressure by increasing the pressure of brake fluid in a reservoir, a master piston moved forward in response to operation of the brake member, a closed chamber defined behind the master piston, a power piston disposed behind the master piston, and a power chamber defined behind the power piston. An auxiliary hydraulic pressure source generates power hydraulic pressure and a pressure regulating device connects the auxiliary hydraulic pressure source with the reservoir. The power hydraulic pressure is regulated to a predetermined hydraulic pressure and is fed to the power chamber. A normally-open type valve connects the closed chamber and the power chamber, and is closable upon operation of the brake member. The closed chamber is connected to the reservoir via the normally-open type valve, the power chamber and the pressure regulating device.
Abstract: Road wheel accelerations are calculated in a controller from respective road wheel velocity values. Any one of the road wheel velocities, including the road wheel velocity of one of the road wheels that is a controlled system in an anti-lock brake control during a brake operation, is selected on the basis of a predetermined condition, any one of the road wheel accelerations is selected from among results of calculations of the road wheel accelerations which corresponds to one of the road wheel velocities which is selected so as to generate a control-purpose road wheel acceleration, and anti-lock brake control is executed for each road wheel during the brake operation using the selected road wheel velocity and the control-purpose road wheel acceleration so as to prevent a wheel's lock for each road wheel from occurring.
Abstract: A vehicle braking control apparatus carries out a pressure apply check to determine if the automatic pressure apply is calculated normally when the vehicle is started. The apparatus includes a fluid pressure generator that generates a master cylinder pressure in response to a pedal depression force, a fluid supplying device that supplies a braking fluid pressure to the wheel cylinders from the master cylinder, and a pressure apply device that introduces the fluid pressure to the pressure chamber of the fluid pressure generator. A controller controls the braking force of each wheel by driving the fluid pressure supplying device and controls pressurization of the master cylinder pressure by automatically controlling the pressure apply device. A pressure apply check device starts a pressure apply check to determine that the automatic pressure apply is calculated normally when the master cylinder pressure is increased up to a fixed value within a fixed time after the pressure apply check is started.
Abstract: The electromagnetic valve is comprised of first communication path and second communication path with a throttle connected in parallel to each other, a first plunger having a first valve for interrupting/communicating the first communication path and having a penetration hole extending to the second communication path, a second plunger having a second valve movable in or through the penetration hole for interrupting/communicating the second communication path, a spring member for generating spring biasing force and a coil member for generating an electromagnetic attracting force, when energized, to have the first and second plungers come close to each other against the spring biasing force. The electromagnetic valve may be controlled in a manner that the first communication path is interrupted and the second communication path is communicated at a pressure-increase timing during an anti-skid control.
Abstract: The present invention is directed to a brake control system for a vehicle, wherein a first valve device for opening or closing a main passage, a hydraulic pressure pump, and a second valve device for opening or closing an auxiliary passage are disposed in each hydraulic pressure circuit of a dual hydraulic pressure circuit system. At least one of the first and second valve devices is controlled to equalize the slip rates of a pair of wheels, with the wheel brake cylinders operatively mounted thereon and disposed in different hydraulic circuits, and placed at the left side and right side of the vehicle, respectively, when a difference between the slip rates of the wheels placed at the left side and right side exceeds a predetermined value.
Abstract: A braking force control device and method performs brake assist control. A timer CT begins to count the elapsed time, for example, from when the elevation gradient &Dgr;PM/C of a master cylinder pressure PM/C becomes equal to or greater than a first threshold value TH2. It is determined that an emergency brake operation is executed, when the master cylinder pressure PM/C becomes equal to or greater than a second threshold value TH1 before a predetermined time has passed, and then the brake assist control starts.
Abstract: A control method of a hydraulic pressure source-driven type vehicle hydraulic pressure brake system in which no irritating noises or vibrations are produced during stoppage of the vehicle and which does not consume electric power in waste. When the vehicle stops and the surroundings become quiet, by detecting stoppage of the vehicle by a sensor for detecting the rotation of a wheel, stopping a motor for a pump for producing brake hydraulic pressure, and opening a solenoid valve in a master cylinder passage bringing the master cylinder and the wheel cylinder into communication with each other, it is possible to prevent noises or vibrations from the motor and wasteful consumption of electric power.
Abstract: The present invention relates to a pressure control valve which includes a valve tappet that is guided in a valve housing and accommodates a compression spring, and a valve closure member which is shaped on the valve tappet and corresponds with a valve seat establishes a connection between a pressure supply conduit extending from a pressure fluid source and a pressure return line when the pressure reaches a defined preset nominal value. To reduce operating noises of the valve tappet, at least one polygonal friction element which engages with the valve tappet is movable into abutment on radial friction surfaces of the valve tappet.
Abstract: In a method and a device for controlling a brake system, the wheel brake pressure is set at the wheel brakes electrically as a function of the driver's braking input. The high-pressure supply arrangement for pressure buildup, for which at least one pump and one accumulator are provided, is monitored by comparing the change in accumulator pressure to a least one permissible limiting value. In the case of a fault in the pressure supply, it is made possible for the driver to grip through hydraulically to the wheel brakes.
Type:
Application
Filed:
February 11, 1999
Publication date:
November 29, 2001
Inventors:
GUNTHER SCHMIDT, JURGEN BINDER, HERMANN WINNER, ULRICH GOTTWICK
Abstract: The present invention relates to an automotive vehicle brake system with wheel slip control which is provided with a so-called filling valve, i.e., a non-return valve, between a secondary and a primary circuit. Initially, both circuits are evacuated for filling the brake system with pressure fluid, and evacuation of the secondary circuit is effected by way of the non-return valve that opens. The present invention suggests providing this valve with a blocking device which becomes effective when the brake is actuated for the first time, thereby causing pressure build-up in the primary circuit. The blocking device retains the valve closure member on the valve seat member, with the result that the non-return valve remains closed in the normal operation of the brake system. It is prevented by this provision that vacuum develops in the secondary circuit during a braking operation.
Abstract: A braking force distribution control apparatus for a vehicle has a lateral acceleration detecting unit detecting lateral acceleration of the vehicle, a longitudinal acceleration detecting unit detecting longitudinal acceleration of the vehicle, a vehicle speed detecting unit detecting a vehicle speed, and a braking control unit adapted to select. When preset conditions for brake operating time are satisfied, the braking control unit executes one of select-low control and independent braking control in accordance with the lateral acceleration, the longitudinal acceleration and the vehicle speed, the select-low control controlling braking forces of left and right wheels depending on a wheel on the side with a large slipping condition. The independent braking control system independently controls the braking force for each wheel in dependency on the slipping condition of each of the wheels.
Abstract: Braking system including a master cylinder having at least two pressurizing pistons partially defining at least two mutually isolated pressurizing chambers, and wherein a working fluid in each pressurizing chamber is pressurized by an advancing movement of the corresponding pressurizing piston, a hydraulically operable brake cylinder for activating a brake, and a valve device having a first state in which the pressurized fluid is delivered from two pressurizing chambers of the at least two pressurizing chambers to the brake cylinder, and a second state in which the pressurized fluid is delivered from only one of the two pressurizing chambers.
Abstract: A vehicular antilock brake control system does not require a lengthy extension piping from its actuator. The system provides for an accurate controlling method for maximizing a calculated road surface friction coefficient. Each wheel has a control unit consisting of a stress sensor, a controller and an actuator installed at the respective wheel. A stress value is detected, representative of road surface friction value or road surface friction coefficient value, for the corresponding wheel independently of the other wheels. In response to the output signal of the sensor, the controller regulates the actuator which controls brake fluid pressure applied to the respective wheel.
Abstract: A multi-way pressure control valve for an electromagnetically actuatable multi-way control valve for slip-controlled hydraulic automotive vehicle brake systems, for providing a flow connection between at least one wheel brake and a high-pressure source or a low-pressure accumulator.
Abstract: A braking control apparatus for vehicles which is capable of generating a braking force in response to a pedal depression force to non-controlled wheels while continuing vehicle stability control. The apparatus generates a brake fluid pressure including a pedal input pressure in response to the pedal depression force and a servo pressure in response to a fluid pressure introduced from a pressure apply unit. A fluid pressure control apparatus supplies brake fluid pressure, an electric control unit controls the braking force of each wheel by driving, and a pedal input pressure estimate portion estimates the pedal input pressure. The electric control unit controls the braking force of the non-controlled wheels during vehicle stability control based on the pedal input pressure estimated by the pedal input pressure estimate portion of the electric control unit.
Abstract: A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a tube. A flux cap is pressed onto one end of the tube. A flux ring pole is pressed onto an opposite end of the tube. An armature is slidably received in the tube. A coil subassembly is provided about the tube, flux cap, and flux ring pole. A valve seat receives the flux ring pole. The valve seat is mounted in a bore of a hydraulic control unit of a vehicular brake system.
Type:
Grant
Filed:
December 29, 1999
Date of Patent:
October 16, 2001
Assignee:
Kelsey-Hayes Company
Inventors:
Herbert L. Linkner, Jr., Wendell D. Tackett
Abstract: When the increasing gradient of the operating power is larger than a predetermined gradient, if a master pressure PM2 corresponding to a second predetermined operating power F2 is larger than a second predetermined fluid pressure Pth2, a servo function failure in the brake operation is determined; if it is smaller than the second predetermined fluid pressure Pth2, fluid leakage failure (S23, S26, S27) is determined. Furthermore, if the master pressure PM0 corresponding to the first predetermined operating power F0 is larger than a first predetermined fluid pressure Pth1, small amount fluid leakage failure is determined; if it is smaller than the first predetermined fluid pressure Pth1, large amount fluid leakage failure (S28, S29, S30) is determined.
Abstract: An ABS return control device for retracting an expander piston to an ABS non-operation position by turning a crank mechanism by a servomotor includes a first procedure of driving the servomotor with a position precedent to a turning limit. At the turning limit, the movement of the crank mechanism is limited by a stopper member. A target angle and a second procedure of driving the servomotor by updating the target angle with the turning limit is further disclosed. The ABS return control device permits reduction of a conventional actuator in size and weight by controlling the kinetic energy of a positioning member of the crank mechanism turned by a servomotor at the time of collision against the stopper member.
Abstract: The present invention is directed to a hydraulic brake apparatus, which includes wheel brake cylinders, and a master cylinder for advancing a master piston in response to operation of a brake pedal. A power chamber is formed behind the master piston. A reaction piston is disposed, with the front end thereof exposed in the power chamber, so as to transmit a reaction force produced by the pressure in the power chamber to the brake pedal. A power source is provided for pressurizing brake fluid stored in a reservoir to supply power pressure to the power chamber. A solenoid valve is provided for opening and closing a return passage which connects the power chamber to the reservoir, thereby to return the brake fluid thereto. A detection device is provided for detecting the amount of operation of the brake pedal. The solenoid valve is controlled in response to the amount of operation detected by the detection device to reduce the amount of the brake fluid in the power chamber.
Abstract: The present invention is directed to a brake control system, which includes wheel brake cylinders, a master cylinder, a reservoir communicated with the wheel brake cylinders, normally open solenoid valves disposed between the master cylinder and the wheel brake cylinders, respectively, normally closed solenoid valves disposed between the wheel brake cylinders and the reservoir, respectively, a hydraulic pump for supplying the brake fluid to a passage for connecting the master cylinder with the normally open valves, and an automatically pressurizing device (e.g., a vacuum booster with a changeover valve) which is provided for advancing the master piston irrespective of operation of the pump and the brake pedal to generate hydraulic braking pressure from the master cylinder.
Abstract: A cup-shaped diaphragm is inserted into a bore formed in a housing. An inlet opening of the bore is closed by a plug-like wall member. A conduit line extends obliquely with respect to an axis of the bore from an annular space formed between a cylindrical wall of the bore and a protruding portion of the plug-like wall member. The annular space is connected to a pressurizing control valve via the conduit line. A chamber, partitioned from the annular space by the cup-shaped diaphragm, serves as a damper chamber which has a diameter substantially equivalent to a diameter of the bore.
Abstract: A vehicle braking pressure source device including (a) a master cylinder having a pressurizing piston cooperating with a cylinder housing to define a pressurizing chamber and a back-pressure chamber on front and rear sides of the piston, and an input rod which slidably extending through a rear end wall of the cylinder housing such that the piston is advanced by a brake operating force of a brake operating member transmitted thereto through the input rod, to pressurize a working fluid in the pressurizing chamber, (b) a communication passage for communication between the pressurizing and back-pressure chambers, (c) a control valve device disposed in the communication passage for controlling the communication between the pressurizing and back-pressure chambers through the communication passage, and (d) a control valve control device for controlling the control valve device, on the basis of at least one of an operating state of the brake operating member, a running state of the vehicle and a state of a road surfa
Abstract: A pump, electromagnetically operable valves and at least one low-pressure accumulator are arranged in a valve block. The valve actuators are disposed in front of a base of the valve block opposite to an electric motor which drives the pump. The housing of the low-pressure accumulator is formed of an add-on piece which is deepdrawn from sheet metal in a bowl-type configuration. The edge of the add-on piece is attached in the mouth of a blind-end bore in the valve block. The add-on piece projects beyond the and has roughly the same height as the actuators of the valves. The actuators and the add-on pieces are covered by a housing cap on the valve block which protects them against environmental influences. The arrangement is extremely compact and permits achieving a relatively small and, thus, light-weight valve block.
Type:
Grant
Filed:
April 7, 2000
Date of Patent:
September 4, 2001
Assignee:
Continental Teves AG & Co., oHG
Inventors:
Hans-Dieter Reinartz, Dieter Dinkel, George Sonnenschein, Stephan Risch
Abstract: Hydraulic motor vehicle braking system with wheel slip controller, comprising a brake pressure applicator (8), which consists of a pedal-activated vacuum brake booster (18) and a main brake cylinder (19) and is connected via a brake line (14) to at least one pair of wheel brakes (2, 3), and a pump (1) connected to the brake line (14) for conveying pressure agent from the brake pressure applicator (8) in the direction of the wheel brakes (2, 3) during wheel slip control, and at least one pressure modulation valve (16, 16′) installed downstream in the brake line (14) to vary the brake pressure in the wheel brakes (2, 3) during the wheel slip control process.
Type:
Grant
Filed:
August 24, 1999
Date of Patent:
September 4, 2001
Assignee:
Continental Teves AG & Co. OHG
Inventors:
Peter Volz, Ronald Kley, Guido Angenendt
Abstract: A solenoid valve for an anti-lock brake system is disclosed in which two orifices and oil passages are formed utilizing a valve seat and a piston. The solenoid valve includes a magnetic core (130) mounted in a bore (101) formed on a modulator (100), a plunger (140) movably mounted in the magnetic core (130), a valve seat (150) disposed below the magnetic core (130) in the bore (101), and a piston (200) movably mounted at the periphery of the valve seat (150). The valve seat (150) has an invariable orifice (320) formed at the inner middle portion of the valve seat, an inlet and outlet passages (300) and (310) formed below and above the invariable orifice (320), respectively. The piston (200) has a variable orifice (340) formed passing through one side of the upper portion of the piston. A lip seal (400) is provided between the outer periphery of the piston (200).
Abstract: A one-time bleed valve with reset capability for an anti-lock hydraulic control unit comprises a piston adapted to be sealingly installed in a bore made in a body of the hydraulic control unit in response to a brake pressure. The bore is located in a portion of the body that is immediately under a recessed part of the body that accommodates a normally open electromagnet valve. On its one end, the bore is in communication with a primary hydraulic pressure circuit, whereas on another its end it is connected with a low-pressure line. Owing to such a structure, when the piston sits loosely in the bore, an air communication is established between the primary hydraulic pressure circuit and the low-pressure line, and air can evacuate from the low-pressure brake circuit on exposure to a vacuum applied to the primary hydraulic pressure circuit. To provide the bleed valve with a reset capability, an access hole is made between outside of the body and the bore.
Abstract: In an electrohydraulic unit for pressure control in brake systems for automotive vehicles which includes mechanical, hydraulic and/or electric structural elements such as control valves, accumulator pistons, pump components and pump drive parts arranged in accommodating bores of a one-part housing, and with parallel accommodating bores for control valves disposed in pairs side by side in two rows in a housing surface, the control valves which are connected to the slave cylinders of one vehicle axle that have a volume requirement lower than the volume requirement of the slave cylinders of the other vehicle axle, and the accommodating bores of these control valves have a smaller diameter and are arranged offset from the middle of the row in the direction of a lateral housing surface.
Type:
Grant
Filed:
September 24, 1999
Date of Patent:
July 17, 2001
Assignee:
Continental Teves AG & Co., OHG
Inventors:
Dieter Dinkel, Albrecht Otto, Stephan Risch, Georg Sonnenschein
Abstract: A hydraulic Control unit of a vehicular brake system includes a housing having a bore formed therein. A normally closed solenoid valve is retained in the bore of the housing. The solenoid valve includes a primary valve and a pilot valve, wherein a cross section of the primary valve is greater that a cross section of the pilot valve. A spring cooperates with the pilot valve so that the pilot valve is open when the primary valve is open.
Abstract: At least one surface contact is formed upon a circuit substrate disposed within a housing for electronic control unit for an anti-lock brake system. The surface contact is electrically connected to a programming port of a microprocessor mounted upon the circuit substrate. A probe is extended into housing and into electrical contact with the surface contact. A algorithm for controlling the operation of the anti-lock brake system is then transferred through the probe and into the microprocessor, where it is stored for use during anti-lock braking operations.
Abstract: An actuating device for an electrohydraulic vehicle brake system has an emergency brake cylinder (2) which comprises a piston (24, 25), the latter being displaceable in a housing (21), and which can be actuated by means of a brake pedal (1), and a simulation device (4) for simulating a force/displacement action of the brake pedal (1), wherein the simulation device (4) is connected in series and disposed after the emergency brake cylinder (2) in the direction of force from the brake pedal (1) to the emergency brake cylinder (2). In order to hydraulically uncouple the simulation device (4) from the emergency brake cylinder (2), the emergency brake cylinder (2) is supported at the simulation device (4) and the piston (24, 25) can be locked relative to the housing (21) such that the simulation device (4) can be mechanically actuated by the emergency brake cylinder (2).
Abstract: In a brake by wire system, a linear differential pressure control valve is provided to control accurately wheel cylinder pressure. A brake fluid conduit extending from a reservoir is branched out into two conduits, each of which is transmitted to each of right and left wheel cylinders. A linear differential pressure control valve is disposed in the conduit and an another linear differential pressure control valve in each of the branched out conduits. Brake fluid sucked from the reservoir by a motor pump is discharged to each of the branched out conduits between the valve and the wheel cylinder. The two valves thus connected in series are operative step by step to control the wheel cylinder pressure in accordance with the current commanded in response to brake pedal depression.
Abstract: A hydraulic automotive brake system with wheel slip control, includes a pressure medium source, to which a main pressure line is connected, which leads to a wheel brake, first and second pressure relief line segments connected to the wheel brake and leading to a supply reservoir, and having a pressure modulation valve arranged in it that either separates the supply reservoir from the wheel brake or connects it to the wheel brake, as well as a control orifice valve that is arranged in the main pressure line upstream of the first pressure relief line segment, actuated by changes in the hydraulic pressure.
Abstract: A vehicle brake system including a wheel brake and a master cylinder operable to provide pressurized fluid to the wheel brake. The master cylinder includes a housing having a bore formed therein, and further including a piston slidably disposed in the bore. The brake system further includes a fluid reservoir in selective fluid communication with the bore of the master cylinder. The brake system also includes an isolation valve movable between an open position, wherein fluid is permitted to flow between the master cylinder and the wheel brake, and a closed position, wherein fluid is restricted from flowing between the master cylinder and the wheel brake. The brake system further includes a dump valve movable between a closed position, wherein fluid is prevented from flowing between the wheel brake and the reservoir, and an open position, wherein fluid is permitted to flow between the wheel brake and the reservoir.
Type:
Grant
Filed:
December 2, 1998
Date of Patent:
April 17, 2001
Assignee:
Kelsey-Hayes Company
Inventors:
Glenn R. Gualdoni, Patrick H. Hool, Serge G. Avenel, Frank P. Lubischer, Norbert Sternal
Abstract: A brake force control apparatus which can quickly supply pressurized brake fluid to wheel cylinders immediately after a condition for starting a brake assist control is established. The brake force control apparatus has emergency brake determining structure for determining an emergency brake operation performed by a driver, a high pressure source for generating a fluid pressure which is higher than a fluid pressure generated by a master cylinder, and a supply for supplying brake fluid from the pump to a wheel cylinder based on the determination made by the emergency brake determining structure. Actuating structure is provided for actuating the high pressure source before the fluid pressure is supplied by the supply.
Abstract: An anti-lock braking system includes a moveable member to be braked and a friction brake for applying a braking force. A controller actuates the friction brake in accordance with braking force demands. Braking force demands are determined by the controller by electrical input signals received from a signal generator that is mechanically linked to the brake pedal, as well as by signals from a slip sensor. The slip sensor records values from wheel speed sensor and computes values that may indicate a slippage condition. Based on the recorded and computed values, the slip sensor and sends electric signals to the controller. The friction brake includes a prestressed piezoelectric element that is lightweight, less cumbersome, and highly controllable as compared with prior anti-lock braking devices, and is actuated via electrical signals rather than a mechanical system.