Abstract: In an electric vehicle in which regenerative braking is performed in preference to hydraulic braking, an uncomfortable vibration generated due to a sudden variation in the load of a motor, is prevented at the start of the regenerative braking. At the start of the braking, the regenerative braking force is gradually increased from a previously set regenerative initial value to a demanded braking force rather than being increased quickly to the demanded braking force, thereby preventing the generation of the vibration. A deficiency in the braking force during this time is compensated for with the hydraulic braking force. When the demanded braking force exceeds a regenerative acceptable value, the regenerative braking force does not exceed the acceptable value, and a deficiency of braking force thereafter is compensated for with the hydraulic braking force.

Abstract: A brake system for a motor vehicle with four wheels has four electrically controlled wheel brake devices. Each of the wheel brake devices has a control part and an actuator, with which the various wheel brakes are activated independently of one another in response to actuations of the brake pedal by the driver. The brake system has two separate electrical control units, each for a respective two of the four wheel brake devices. Both of the separate control units receive control signals separately from a brake force simulator, and they each have their own energy supply circuit. An additional central control unit controls additional functions of the system (ABS, traction control, etc.) at each of the four wheel brake devices which serve safety or comfort purposes of the motor vehicle.

Abstract: Vehicle hydraulic braking system including a brake including a wheel brake cylinder operated with a pressurized fluid to brake a vehicle wheel, a seating valve having a valve member movable toward and away a valve seat and biased in a first direction for seating of the valve member onto the valve seat, and a valve driving device for generating a valve drive force acting on the valve member in a second direction opposite to the first direction, and a seating valve control device for controlling the valve driving device to selectively open and close the seating valve, for thereby regulating a pressure of the fluid in the wheel brake cylinder, and wherein the seating valve control device includes a seating velocity reducing device for commanding the valve driving device to generate a valve drive force, during at least a portion of a movement of the valve member for seating onto the valve seat, for reducing a seating velocity of the valve member.

Abstract: The present invention is directed to a brake control system for an electrically operated vehicle which is adapted to add a hydraulic braking operation to a regenerative braking operation, or change the former for the latter, rapidly and smoothly. An electric motor is operatively connected to a wheel for rotating the wheel, and a motor control unit for controlling the electric motor to apply a rotating force and a regenerative braking force to the wheel. In a main passage for connecting a master cylinder with a wheel brake cylinder, a pressure limit changeover device is disposed.

Abstract: A brake apparatus for an electric automobile applies brakes to the vehicle to achieve a required amount of braking force by combining regenerative braking force of an electric motor with mechanical braking force produced by a mechanical braking system. The braking force required by a driver is obtained from the depression force applied to a brake pedal, and the maximum regenerative braking force, that can be generated by the motor, is obtained from the rotation speed of the motor. The target mechanical braking force is calculated based on the required braking force and the maximum regenerative braking force. By suitably controlling the pneumatic pressure applied to a booster device provided in the mechanical brake system, the fluid pressure actually applied to brake actuating members is controlled to provide the target mechanical braking force.

Abstract: A regenerative brake controller for controlling a value of regenerative braking torque to simulate engine braking torque. When the shift lever is in the D range, from a first control map which correlates the vehicle speed and the like with target braking torque or target deceleration, the controller reads the target braking torque or target deceleration corresponding to the vehicle speed immediately before the release of the accelerator pedal, and controls the vehicle components on the basis of the read target braking torque or target deceleration such that the regenerative braking torque corresponding to the engine braking torque is produced.

Abstract: A brake apparatus for an electric vehicle which maintains the regenerative energy generated in a traction motor of each of wheels to be at a maximum. A hydraulic pressure brake and a regenerative brake are provided in the same brake apparatus. The hydraulic pressure brake generates a brake torque by providing a hydraulic pressure to a wheel cylinder of each wheel of the vehicle. The regenerative brake generates a brake torque by regeneration in a traction motor for each wheel. The brake torque to be provided is calculated for each wheel. A maximum regenerative energy is calculated for each wheel. A hydraulic pressure calculating unit calculates a hydraulic pressure to be provided to the wheel cylinder of each wheel based on the brake torque and the maximum regenerative energy so that the regenerative energy generated by the traction motor of each wheel becomes a maximum.

Abstract: The present invention is directed to a brake control system for controlling a braking force applied to a wheel of an electrically operated vehicle. A changeover device is disposed in a main passage for selectively placing one of a first operating position where a static hydraulic pressure supplied from a master cylinder to a wheel brake cylinder is controlled to be lower than a master cylinder pressure generated from the master cylinder when an electric motor applies the regenerative braking force to the wheel, and a second operating position where the static hydraulic pressure is controlled to be substantially equal to the master cylinder pressure when the electric motor does not apply the regenerative braking force to the wheel.

Abstract: According to the present invention, the operating amount of the brake is detected, and the target value of the regenerative torque is set in accordance with the detected operating amount. In the meantime, the change in the detected operating amount along with time is detected, and the rise speed of the regenerative torque is set in accordance with the detected change along with time. The regenerative torque is controlled in accordance with the set target value of the regenerative torque and the set rise speed.

Abstract: In an electric vehicle the driven wheels connected to an electric motor are liquid-pressure braked in a condition in which a differential pressure regulating valve interposed between the driven wheels and a master cylinder has been opened, and the driven wheels are regeneratively braked in a condition in which the differential pressure regulating valve has been closed to inhibit the liquid pressure braking. By temporarily opening the differential pressure regulating valve at the start of depression of the brake pedal, a stroke of the brake pedal depending upon the play of the brake caliper is previously absorbed. Thus, when the differential pressure regulating valve has been opened to switch over the regenerative braking to the liquid pressure braking, the change in stroke of the brake pedal can be reduced by a stroke amount that corresponds to the play of the brake caliper.

Abstract: In a first region of the driver's braking command, regenerative braking produces almost all of the braking torque, whereas the friction brake produces essentially no braking torque. In this region of the braking command, the pressure medium flowing into the wheel brake cylinder as a result of the driver's actuation of the brake pedal, is conducted by appropriate control back to a storage chamber. The first region is limited by a threshold brake pedal travel which corresponds to the maximum braking torque available from the motor. When pedal travel exceeds this threshold, the friction brake and the motor both effect braking.

Abstract: A braking control system for an electric automobile combines the use of mechanical braking and regenerative braking by a motor. Namely, a braking control system for the electrical automobile, which permits the combined use of regenerative braking and mechanical braking, is provided with target braking force setting unit (9) for setting a target braking force on the basis of a brake pedal stroke, regeneration control system (4A,5A) for setting a target regenerative braking force on the basis of the brake pedal stroke and then controlling regenerative braking by the motor in accordance with the target regenerative braking force, and mechanical braking control unit (24) for controlling operation of a mechanical brake system (B) in accordance with a difference between said target braking force and an actual braking force determined based on a detected deceleration of a vehicle.

Abstract: This invention relates to a braking control system for an electric automobile that runs by driving wheels with an electric motor. The braking control system controls braking of a vehicle through regenerative braking by the motor. Upon application of brakes, the braking control system can make combined use of mechanical braking by a mechanical brake system (11) and regenerative braking by a drive motor (2). The braking control system is designed to control regenerative braking of the motor (2) by a regenerative braking control device (12) so that greater braking force is produced when a failure in the mechanical brake system (11) is detected by a failure detection device (22) than when the mechanical brake system (11) is detected to be normal.

Abstract: A brake unit for motor vehicles with electric drive with a hydraulic pressure transducer and hydraulic friction brakes to increase the brake effect applied by the electric drive motor. The cooperation of the electric drive motor with the hydraulic friction brakes is controlled by an electronic controller.

Abstract: A controller for controlling supply of electrical current to the coils or coil groups of an electromagnetic retarder for applying drag torque to a turning shaft or drive line. The controller includes an input signal receiving element for receiving input signals from at least one input device, a control unit responsive to the input signal for modulating electrical current supply from at least one current source to the retarder coils so that current is distributed to each of the coils or coil groups substantially equally.

Abstract: A braking force control system of an electric vehicle includes a regenerative-controllable motor for driving driven wheels, wheel cylinders for braking non-driven wheels, respectively, and a master cylinder connected to a brake pedal for producing a master cylinder pressure in proportion to a depression amount of the brake pedal. A mechanical braking force control unit is further provided in a working fluid passage from the master cylinder and the wheel cylinders. The mechanical braking force control unit includes a proportioning valve and a free-piston cylinder arranged in parallel with each other in the working fluid passage. The proportioning valve is operated to output a wheel cylinder pressure to the wheel cylinders when the depression amount of the brake pedal is no more than a given value. On the other hand, the free-piston cylinder is operated to output a wheel cylinder pressure to the wheel cylinders when the depression amount of the brake pedal is more than the given value.

Abstract: In a vehicle with a first set of first and second wheels coupled to an electric drive system capable of providing regenerative braking and a second set of third and fourth wheels, wherein the vehicle dynamically adjusts a brake proportioning between the first and second sets responsive to a determined wheel speed difference between the first and second sets, the improvement comprising a regenerative braking control method according to the steps of: measuring first, second, third and fourth speeds of the first, second, third and fourth wheels; for each wheel of one of the first and second sets, determining a set-off value inversely relational to a commanded brake torque and a wheel deceleration; determining modified wheel speeds for each wheel of said one of the first and second sets responsive to the wheel speeds and the set-off values; and determining the wheel speed difference between the first and second sets responsive to the modified wheels speeds of said one of the first and second sets and the wheel sp

Abstract: A braking force controller for an electric vehicle properly carries out an anti-lock braking operation by keeping a slip ratio in a stable range. The vehicle has a motor 1 to drive wheels. A central controller 4 calculates regenerative energy according to output signals from an ammeter 51 and a voltmeter 52. If a brake sensor 62 detects a sudden braking operation, the central controller 4 controls the regenerative braking force of the motor 1 through a motor controller 2, to maintain the regenerative energy around a maximal value.

Abstract: An electric-powered vehicle having a drive system which includes at least one electric motor which is controlled and monitored by an electric control system for driving at least one vehicle wheel in a traction mode of the motor and also for selectively providing a contribution to overall braking torque when operated in a braking mode, and which also provides a hydraulic braking system which is actuated by the vehicle driver and which operates on at least the front wheels of the vehicle. The hydraulic braking torque produced by the driver by way of the hydraulic braking system, is adjusted in such a manner that, for the purpose of modulating the overall braking torque effective at the vehicle wheels the variation of the electric torque is arranged to stay within the "regenerative range" of operation of the electric motor, at least under predetermined operating conditions of the vehicle.

Abstract: A vehicle has an electric propulsion motor, a regenerative brake control and an anti-lock friction brake system which responds to excess wheel slip of a front wheel during braking to modulate friction braking torque to reduce the excess wheel slip. It further has a control responsive to activation of the anti-lock brake system to prevent the application of regenerative braking during such activation. The regenerative braking may be blended with the friction braking when anti-lock braking is not activated so that battery charge is conserved. When the anti-lock braking is activated, however, the regenerative braking is ramped down to preserve smoothness in the braking. The regenerative braking may be applied to create drag during vehicle coastdown. When anti-lock braking is activated, if it is sensed that the wheel is on a low friction (.mu.) surface, the regenerative braking is removed immediately.

Abstract: A vehicle (31) has a composite braking system (electric and mechanical). This composite braking system having asynchronous electric motors (4a to 4d) associated with the wheels (2a to 2d) and a mechanical braking device having a hydraulic circuit (14) and mechanical brakes (18a to 18d). The composite braking system also has an electronic measuring device (36) connected to rotation frequency sensors (34a to 34d) disposed on each of the wheels, this electronic device supplying a reference signal to the control circuit (6) of the asynchronous electric motors which regulate the stator frequency of these motors as a function of the value of the reference signal. The braking system of the invention is anti-locking and very effective in any driving situation.

Abstract: A braking system for an electromobile includes a relief valve VR2 for restricting a braking pressure to front wheel cylinders WC3, WC4, a bypass valve V5 connected in parallel to the relief valve VR2, a solenoid valve V1 interposed between the relief valve VR2 and booster HB and a solenoid valve V4 interposed between a pressure line 13 from the booster HB to the front wheel cylinders WC3, WC4 and a pressure line 12 from the booster HB to rear wheel cylinders WC1, WC2. During a regenerative braking by the use of an electric motor for driving front wheels WFL, WFR, a braking pressure is applied through the solenoid valve V1 and the relief valve VR2 to the wheel cylinders WC3, WC4. When the regenerative braking is interrupted, the solenoid valve V1 is closed and the bypass valve V5 and the solenoid valve V4 are opened.

Abstract: In order to keep the braking torque of a motor always maximal and to execute suitable ABS regenerative braking, a controller of an electric car has a motor (1) connected to the road wheels, and its central controller confirms that regenerative energy calculated from output signals from an ammeter (51) and from a volt meter (52) after the braking operation begins reaches a maximum value, and stores a braking torque calculation value obtained from a signal from a motor number-of-revolution sensor (63), as a maximum braking torque value. When the difference between the braking torque command value applied to the motor (1) and the braking torque calculation value exists within a predetermined range, the braking torque command value is thereafter increased or decreased in accordance with the difference between the maximum braking torque value described above and a present braking torque calculation value, and when the difference is out of this predetermined range, the braking torque command value is decreased.

Abstract: In an electric vehicle capable of being regeneratively braked, driven wheels connected to and driven by a motor are connected to and capable of being regeneratively braked by a brake control unit. When the regenerative braking of the driven wheels is being conducted by the brake control unit, the gear-shifting of an automatic transmission by a motor/AT control unit is prohibited. Thus, the need for continuance or control of the regenerative braking during gear-shifting is eliminated, thereby preventing a reduction in braking force during the gear-shifting and the generation of a shock.

Abstract: A method of brake system control, and apparatus for performing same, comprising the steps of (i) determining a brake command for right and left wheel brakes; (ii) monitoring right and left wheel speeds; (iii) comparing the right and left wheel speeds to determine a speed difference; (iv) if the right wheel speed is greater than the left wheel speed, adjusting a left gain of the of a left brake command to reduce torque provided by the left wheel brake; (v) if the left wheel speed is greater than the right wheel speed, adjusting a right gain of a right brake command to reduce torque provided by the right wheel brake.

Abstract: A regenerative and friction brake blend control method for use in a vehicle with at least one positionable hydraulic brake actuator for achieving friction braking and an electric propulsion motor with regenerative braking capability wherein an amount of regenerative braking achieved is indicated by a signal, wherein the method comprises the steps of determining a hydraulic actuator position command indicating a desired vehicle braking, determining responsive the hydraulic actuator position command a regenerative braking command, commanding the electric propulsion motor to regeneratively brake the vehicle responsive to the regenerative braking command, receiving the signal indicative of regenerative braking achieved, converting the signal indicative of regenerative braking achieved to an actuator position reduction signal, subtracting the actuator position reduction signal from the hydraulic actuator position command to determine a difference command, and commanding the hydraulic actuator according to the diff

Abstract: The invention is directed to an anti-skid control system for an electrically operated vehicle having an electric motor and a regenerative braking system. The system sets a desired decreasing wheel speed, when a skid detector detects a skidding condition of the wheel in response to the output signal of a wheel speed detector. A controller controls a regenerative braking torque of the electric motor in accordance with a control mode selected from a torque control mode, in which the regenerative braking torque is provided in proportion to operation of a brake operating member, and a rotation control mode, in which the regenerative braking torque is controlled to rotate the electric motor at a predetermined speed corresponding to the desired decreasing wheel speed. The controller changes the torque control mode to the rotation control mode when the skid detector detects the skidding condition.

Abstract: A vehicular powertrain with regenerative braking includes a plurality of wheels and a brake pedal which, upon engagement, is activated first into a first zone of operation and then into a second zone of operation. A braking detector detects either a released state or an engaged state for the brake pedal and, if in the engaged state, detects if the pedal is in the first or the second zone of operation. Friction brakes brake a pair of the wheels, responsive to detection of the brake pedal within the second zone of operation. The hydraulic portion of the drivetrain includes an accumulator for storing hydraulic fluid under pressure and a reservoir for storing the hydraulic fluid at a lower pressure. A pump/motor is located in the high pressure line for operation as a motor to drive the drive wheels in a drive mode and for operation as a pump driven by the drive wheels in a braking mode.

Abstract: A braking apparatus for an electric vehicle in which a mechanical anti-lock brake and regenerative braking cooperate with each other to improve a braking performance is realized. On condition that an accelerator is released off, the wheel rotation number is large, and a brake is trod on, a large regeneration mode is selected by a motor controller when a wheel slip is small, and a regeneration mode is selected when the wheel slip is large. When the wheel slip is small, the braking force exerted on each wheel is increased by the brake controller and the regenerative braking force is also increased so that a slip ratio comes quickly closer to 0.2. When the wheel slip is large, the brake controller reduces the braking force so that the slip ratio comes closer to 0.2. In this case, the regenerative braking force is smaller than the above case of the small wheel slip to such an extent that the operation of the brake controller is not disturbed.