1391 results about "Wheel cylinder" patented technology

A brake control system includes a master cylinder to produce a master cylinder pressure, a brake booster to assist the master cylinder, a first control unit to control the booster, a hydraulic modulator to supply a wheel cylinder pressure to a wheel cylinder, and a second control unit to control the hydraulic modulator. The hydraulic modulator includes a pressure source, such as a pump, to increase the wheel cylinder pressure. The first and second control units are connected together by a communication line. The brake control system may further include a boost condition transmitting section to transmit, through the communicating line, a condition of a boost system formed by the brake booster and the first control unit.

An agricultural implement system is provided that includes a down force cylinder configured to apply a downward force to a row unit, a depth control cylinder configured to vary a penetration depth of a ground engaging tool of the row unit, a press wheel cylinder configured to vary contact force between a press wheel and a soil surface, a closing disk cylinder configured to vary contact force between a closing disk and the soil surface, a residue manager cylinder configured to vary contact force between a residue manager and the soil surface, or a combination thereof. The agricultural implement system also includes an electronic control unit configured to automatically regulate a pressure within the cylinders, and a manual backup system configured to facilitate manual pressure adjustment of the cylinders.

When an electrical fluid pressure generator fails and a wheel cylinder is operated by brake fluid pressure generated by a master cylinder, if a first fluid pressure system leading to a rear fluid chamber of the electrical fluid pressure generator fails and is opened to the atmosphere, braking is performed by brake fluid pressure of a second fluid pressure system transmitted from the master cylinder through a front fluid chamber of the electrical fluid pressure generator to a wheel cylinder. At this time, a front supply port, which communicates through a front second cup seal facing rearward with the rear fluid chamber opened to the atmosphere due to the failure, does not communicate with the master cylinder but with a reservoir. Therefore, it is possible to prevent leakage of the brake fluid pressure generated by the master cylinder through the front supply port, the front second cup seal and the rear fluid chamber, thereby ensuring braking by the second fluid pressure system leading to the front fluid chamber of the electrical fluid pressure generator.

A brake control apparatus of an automotive vehicle employs a pump incorporated in a hydraulic actuator, a separate pressure control valve disposed between the pump and each individual wheel-brake cylinder and having an orifice having a predetermined orifice-constriction flow passage area, and vehicle sensors including at least wheel cylinder pressure sensors. Also provided is a controller configured to be connected to the vehicle sensors and the hydraulic actuator, for calculating, based on a driver's manipulated variable, target wheel cylinder pressures, and for controlling the hydraulic actuator responsively to the target wheel cylinder pressures. The controller is further configured for calculating a fluid-pressure deviation between the target wheel cylinder pressure and the actual wheel cylinder pressure, and for stopping working-fluid supply from the pump to the abnormal wheel-brake cylinder having an abnormality in the fluid-pressure deviation exceeding a predetermined threshold value.

An apparatus for controlling brakes, includes a first brake circuit for supplying brake fluid, pressure-increased by a booster, to a wheel-brake cylinder, a first control valve disposed in the first brake circuit for establishing and blocking fluid communication between a master cylinder and the wheel-brake cylinder, a second brake circuit arranged in parallel with the first brake circuit for supplying brake fluid, pressure-increased by a fluid-pressure source, to the wheel-brake cylinder, and a second control valve disposed in the second brake circuit for establishing and blocking fluid communication between the fluid-pressure source and the wheel-brake cylinder. Also provided is a control unit, which is configured to selectively control the first and second control valves when building-up wheel-cylinder pressure, and further configured to build-up the wheel-cylinder pressure by operating the fluid-pressure source when at least the second control valve is controlled to a valve-open position.

A brake control apparatus includes a brake unit. The brake unit includes: a first port set hydraulically connected to a master cylinder via a first fluid line set; a second port set hydraulically connected to a wheel cylinder set via a second fluid line set; a first fluid passage hydraulically connecting the first port set to the second port set; a first switching valve arranged to vary a state of fluid communication through the first fluid passage; a fluid pressure source arranged to produce a fluid pressure supplied to the second port set; a fluid accommodating section adapted to accommodate a variable amount of brake fluid; a branch fluid passage hydraulically connecting the first port set to the fluid accommodating section; and a second switching valve arranged to vary a state of fluid communication through the branch fluid passage.

The invention discloses a stability integrated control method of a vehicle. The stability and the ride comfort of the vehicle are guaranteed by regulating the front-wheel steering angles and the braking force of corresponding tires. The control method comprises the following steps of collecting the running state information of the vehicle, and carrying out wave filtering and estimation treatment; planning a reference state value through which the vehicle is enabled to run stably; evaluating the stability risk of the vehicle according to the actual running state of the vehicle and the reference state value; when the vehicle does not have the stability risk, unnecessarily carrying out control, otherwise, necessarily planning and deciding front-wheel steering angles and additional yawing moments, through which the vehicle is enabled to recover the stability; converting the additional yawing moments into the expected braking force of the corresponding tires, meanwhile, comparing the expected braking force with the actual pressure of a wheel cylinder, and determining a solenoid valve action instruction; actuating the solenoid valve action instruction and a front-wheel steering angle instruction by a braking actuator and a steering actuator, so that the vehicle is enabled to recover to run stably.

The invention discloses an electro-hydraulic composite braking system with an electric braking assistant force and a brake-by-wire function. The electro-hydraulic composite braking system provided by the invention has various working modes In the case of an electric braking assistant force mode, a brake fluid is input into a master cylinder from a man-power cylinder by a brake pedal, and meanwhile, an electronic control unit controls the output torque of a motor to apply an assistant force, so as to output brake pressure to a wheel cylinder. In the case of a regenerative braking mode, the electronic control unit controls the on/off of an electromagnetic valve, the brake fluid is input into the simulation cavity of a pedal travel simulator from the man-power cylinder by the brake pedal so as to generate pressure and provide a brake pedal feeling; if automobile deceleration requirement can not be met by the regenerative braking, the electronic control unit controls the output torque of the motor so as to allow the master cylinder to output brake pressure into the wheel cylinder to assist friction brake. In case of an active braking mode, the electronic control unit controls the output torque of the motor so as to allow the master cylinder to output brake pressure to the wheel cylinder. The electro-hydraulic composite braking system provided by the invention has the advantages of integration of advantages of wire control and non-wire control working modes, small pressure fluctuation, and high pressure regulation precision.

The invention relates to a method for improving lateral stability under the condition of turning/braking vehicles, in particular to an automobile brake control method for improving lateral stability of turning/braking vehicles. By an off-line simulation method, from the angle of whole-vehicle dynamics, based on optimization technology, the invention calibrates an optimal target slip-rate working interval of an automobile ABS system comprehensively considering both longitudinal braking performance and lateral braking performance under the turning/braking condition, forms a curved surface from target slip rate to steering angle to initial braking speed, and then supplies the target slip rate for dynamically adjusting wheels inside and outside a bend to an online ABS system. The online ABS system adjusts the pressure of a braking wheel cylinder to reasonably allocate longitudinal force and lateral force that every wheel bears when a vehicle turns/brakes so as to improve the lateral stability of the vehicle. On the basis of the prior ABS system, the method has the advantage of allowing the ABS system to have part of the functions of an ESP system without increasing any cost.

A hydraulic brake system includes a first actuator for a regeneration coordination brake control and a second actuator for maintaining the stability of a vehicle in a hydraulic pressure passage between a master cylinder and a wheel cylinder. The first actuator is controlled by a first ECU, and the second actuator is controlled by a second ECU. When a failure occurs in the first actuator or the first ECU, the second ECU operates the second actuator according to the amount of a brake operation, and assists braking of a wheel.

The invention relates to an electric-hydro complex brake system employing an integral brake master cylinder assembly for vehicle, including: a brake pedal, a pedal displacement sensor, an integral brake master cylinder assembly and an ABS hydraulic control unit, which are in turn connected. The ABS hydraulic control unit is connected with brake wheel cylinders of four wheels of the vehicle. Compared with the prior art, in a state that the electric system of the vehicle does not work, the hydraulic pressure inside the integral brake master cylinder assembly assists a first chamber to amplify the input force of the push rod of the master cylinder, and a pedal simulation spring drives and assists a second piston, a first piston for the master cylinder and a second piston for the master cylinder, in order to form the pressure required by braking.

An object of the present invention is to provide a brake apparatus in which a hydraulic pressure in a master cylinder is prevented from being increasingly varied while an anti-lock brake system is in operation, and therefore a pedal feeling can be improved. The brake apparatus comprises an electric booster including an input member which moves forward or backward in response to an operation of a brake pedal, an assist member which moves forward or backward by being driven by an electric actuator using an electric motor as its driving source. The electric booster generates a boosted brake hydraulic pressure in the master cylinder under an input thrust provided to the input member through the brake pedal and an assist thrust provided to the assist member by the electric actuator. In the brake apparatus, the brake hydraulic pressure generated in the master cylinder is supplied to a wheel cylinder through a hydraulic pressure circuit of an anti-lock brake system, and, while the anti-lock brake system in operation, an operation of the assist member is restricted by a booster control, whereby a change in a hydraulic pressure in the master cylinder due to the operation of the assist member can be restrained.

The invention provides an elevator rolling guide shoe with a brake function. The elevator rolling guide shoe is provided with a rolling guide wheel mechanism, hydraulic execution mechanisms and stop mechanisms, wherein three guide wheels of the rolling guide wheel mechanism cling to three working surfaces of a T-shaped guide rail and are used for limiting the horizontal movement of an elevator car; the hydraulic execution mechanisms are connected with the guide wheels of the guide shoe and used for determining whether pressures are applied to the guide wheels according to a detected elevator running state; and the stop mechanisms are integrated in the guide wheels and used for stopping the guide wheels when an elevator is in a post stall state and enabling the guide wheels to tightly hold the guide rail in combination with pressing forces provided by the hydraulic execution mechanisms, so that the emergency braking is achieved; and each stop mechanism is composed of the following parts: a guide shoe base, a long connecting rod, a main swing rod, a secondary swing rod, a brake bottom plate, a hydraulic wheel cylinder, a brake shoe, a brake pad and a brake drum covered by wear-resistant rubber.

A brake control apparatus has first and second wheel cylinders; a master cylinder unit; first and second systems; a separation valve; a pressure control mechanism that controls the working fluid pressure transferred to at least one of the first and second wheel cylinders independently of the brake operation, and a brake ECU. The brake ECU generates a differential pressure across the separation valve by operating the pressure control mechanism when there is no brake operation while a running drive source of a vehicle is stopped to determine whether the separation valve has a leakage abnormality.

An object of the present invention is to simplify a control during regenerative cooperation in a brake control system generating a hydraulic pressure in a master cylinder by displacing a piston with use of an electric actuator according an operation amount of a brake pedal. The brake control system displaces the primary piston 8 by controlling an operation of the electric motor 22 by a master pressure control unit 4 according to the operation amount Xop of the brake pedal 19, thereby generating a hydraulic pressure in the master cylinder 2 to supply it to wheel cylinders Ba to Bd. The master pressure control unit 4 sets a target relative displacement ΔXT between an input piston 17 and the primary piston 8 and a target hydraulic pressure PT in the master cylinder 2, and appropriately switch which is used to control a brake force. During regenerative cooperation, the master pressure control unit 4 selects the control with use of the target hydraulic pressure PT, which enables easy execution of a hydraulic pressure control including a subtraction of the hydraulic pressure corresponding to a brake effect from the regenerative cooperation.

The invention relates to an accelerator pedal and brake pedal-based electrically driven automobile feedback brake control method, which comprises the following steps of: (1) arranging an electrically driven automobile feedback brake control system comprising a vehicle controller, a wheel speed sensor, an accelerator pedal displacement sensor, a pressure regulator, a main cylinder pressure sensor, a front wheel cylinder pressure sensor and a brake pedal switch; (2) judging, by the vehicle controller, braking intention of a driver according to a current operation state of the automobile, dividing brake feedback control into three stages, i.e., an accelerator pedal-based feedback control stage, a brake pedal-based feedback control stage and a control stage of a switching process from accelerator pedal-based feedback to brake pedal-based feedback; and (3) calculating, by the electrically driven automobile feedback brake control system, motor feedback braking force of the three feedback control stages respectively, thereby keeping the vehicle total brake force consistent with the driver brake requirement. The accelerator pedal and brake pedal-based electrically driven automobile feedback brake control method can be widely applied to electrically driven automobile feedback brake control of a pure electric vehicle, a hybrid electric vehicle and the like.

During regenerative coordinate braking control, a target brake force is defined by eliminating influences of brake system component tolerances to achieve a comfortable brake feel and secure regenerative energy. A brake control system includes a master cylinder, wheel cylinders, a VDC brake fluid pressure unit and a motor controller. In response to a brake pedal operation by a driver, a brake pedal stroke position is detected at which a pressure in a master cylinder actually begins to be generated. A target deceleration characteristic is adjusted from a theoretical characteristic so that the target deceleration equals a maximum value of an add-on brake force (i.e., the regenerative brake gap) at the detected brake pedal stroke position.

The invention discloses an electro-hydraulic braking system and a control method thereof for an electric automobile. The electro-hydraulic braking system is provided with a high-voltage brake circuit, a low-voltage brake circuit and a standby brake circuit, wherein the high-voltage brake circuit comprises a first hydraulic pump, a high-voltage energy accumulator, a three-position and three-way valve and a corresponding brake wheel cylinder which are sequentially connected; a pressure sensor is arranged near a pipeline at an output rear end of the high-voltage energy accumulator; the low-voltage brake circuit comprises a second hydraulic pump, a low-voltage energy accumulator, a three-position and three-way valve and a corresponding brake wheel cylinder which are sequentially connected; when the pressure of the pressure sensor is lower than a preset value; the first hydraulic pump sucks hydraulic oil and pumps the hydraulic oil into the high-voltage energy accumulator for enabling the automobile to brake; the second hydraulic pump sucks hydraulic oil and pumps the hydraulic oil into the low-voltage energy accumulator for enabling the automobile to brake; when the brake strength is higher than the brake strength which can be provided by the low-voltage brake circuit, the high-voltage brake circuit is started; when the brake strength which can be provided by the low-voltage brake circuit meets the required brake strength, a low-voltage brake mode is started; and a favorable safety performance is obtained and brake energy can be recovered to the maximum extent.

A brake control apparatus for a vehicle provided with a regenerative braking device, the brake control apparatus includes: a first brake circuit connecting a master cylinder configured to generate a brake hydraulic pressure by a brake operation of a driver, and a wheel cylinder to which the brake hydraulic pressure is applied; a booster configured to increase a pressure of a brake fluid within the master cylinder, and to transmit the pressurized brake fluid to the wheel cylinder through a second brake circuit connected with the first brake circuit; a third brake circuit bifurcated from the first brake circuit, and connected with the booster; a reservoir provided on the third brake circuit; and a recirculating device configured to recirculate the brake fluid stored in the reservoir, to the first brake circuit's side.

The invention provides a brake control apparatus that improves the controllability of a vehicle in the control for restraining slip of the wheels. The brake control apparatus includes: wheel cylinders that apply braking force individually to wheels by supplying a working fluid; retention valves that are provided respectively upstream of the wheel cylinders and that are opened and closed so as to restrain slip of the wheels; a common control valve provided upstream of the retention valves to supply the working fluid to the wheel cylinders; and a control portion that controls the common control valve by different control laws to restrain fluctuations in pressure on a primary side of the retention valves caused by fluctuations in a capacity to which the working fluid from the common control valve is supplied, by opening or closing of the retention valves.

A hydraulic double-motor driving electronic hydraulic braking system comprises a braking pedal, a braking master cylinder, a secondary master cylinder, a liquid storage tank, a pedal displacement sensor, a hydraulic pressure sensor, an electronic control unit ECU, a first electronic control linear moving module and a second electronic control linear moving module for performing active control on hydraulic braking force and pedal force of the system, an electronic stability control module ESC for regulating the hydraulic braking force of each wheel cylinder, a tee joint for connecting hydraulic pipelines between the braking master cylinder and the inlet of the electronic stability control (ESC) module as well as between the secondary master cylinder and the inlet of the ESC module. According to the invention, the pedal force of a driver can be utilized for pressure establishing, the active control on the pedal force is realized while a pedal force simulator with a complex structure is omitted, braking pedal feel is ensured, the braking intention of the driver can be correctly reflected, the active control on hydraulic pressure is realized, the braking requirement of a vehicle is met, maximum braking energy recycling can be realized, the control is precise, and the response speed is high.

The invention discloses a brake energy recovery hydraulic braking system based on a VDC (Vehicle Dynamics Control)/VSC (Vehicle Stability Control)/ESP (Electronic Stability Program) pressure regulator, comprising a pressure regulator with the function of VDC/VSC/ESP, a braking main cylinder, a braking electric motor, a braking controller and a hybrid control unit. The brake energy recovery hydraulic braking system is characterized in that a main cylinder pressure sensor is arranged on an oil outlet pipeline of the braking main cylinder; a wheel cylinder pressure sensor is arranged on a front wheel cylinder of the pressure regulator; signals of the main cylinder pressure sensor and the wheel cylinder pressure sensor are all fed back to the braking controller; a drive electric motor is controlled by the hybrid control unit; and the braking controller performs CAN (Controller Area Network) communication with the hybrid control unit. The pressure regulator controls two paths of braking oil paths of front left wheel-right rear wheel and right front wheel-left rear wheel. The invention utilizes the drive electric motor to return braking torque to carry out brake energy feedback, utilizes the VDC/VSC/ESP pressure regulator to realize the increase, the maintenance and the decrease of the pressure of the wheel cylinder, ensures the drive safety, and can realize the regenerative braking and the integrated control of ABS (Anti-lock Brake System), ASR (Acceleration Slip Regulation) and ESP (Electronic Stability Program).

The invention discloses a dual-motor BBW system with multiple working modes and voltage regulation modes. A brake fluid in a manual cylinder flows into two main cylinders by means of a brake pedal, and brake pressure is generated; and meanwhile, output power torque of two motors is controlled, and axial thrust is overlaid to pistons of the two main cylinders through a transmission device, so that electric power brake is realized. Through control of output torque of the two motors, pressure of the two main cylinders is transmitted to wheel cylinders, brake by wire is realized, and a pedal travel simulator is used for providing force for the brake pedal. Under the condition that the brake pedal is not stepped, the output torque of the two motors is controlled, so that the two cylinders generate pressure which is transmitted to the wheel cylinders through a hydraulic control unit, and accordingly, the active brake is realized. The invention further discloses a structure of a hydraulic control system, and the structure has multiple voltage regulation modes. The dual-motor BBW system has the advantages as follows: the system has multiple braking modes and voltage regulation modes, the most appropriate braking mode and voltage regulation mode can be selected according to dynamic properties of the motors during implementation and application, the reliability is high, and the failure protection capacity is high.