43results about How to "Ensure braking stability" patented technology

Disclosed is a method for optimizing braking force distribution of an integrated braking system of a commercial vehicle according to working conditions. The method for optimizing braking force distribution of a front axle friction brake, a rear axle friction brake and an eddy current retarder is provided for the commercial vehicle equipped with an air pressure electric control braking system and the eddy current retarder, and the difference of the requirements of the emergency braking working condition, the long slope downhill braking working condition and other ordinary braking working conditions for the braking response speed, the braking distance, the brake temperature and the friction liner abrasion uniformity is taken into consideration, so that different control targets and different braking force distribution strategies are adopted according to different braking working conditions. The method has the advantages that the braking response speed of the braking system is increased, the temperature rise of the brakes under the downhill working condition is reduced, the service life of each friction liner is prolonged, accidents are avoided, the safety under various braking working conditions is improved, the service life of each friction brake and the service life of the eddy current retarder are prolonged, the maintenance frequency is reduced, and the economical performance is improved.

The invention relates to a straight driving cycle-oriented real-time optimal torque distribution control method for a 4-wheel independent driving electric vehicle. In allusion to the problem of torquedistribution of a 4-wheel independent driving electric vehicle taking a wheel hub motor as a power unit under a straight driving cycle, a corresponding online optimal distribution control algorithm is formulated; an optimal distribution coefficient table acquired offline is further utilized to perform compensation and correction on an online optimal result; and a torque distribution function anddesign coupling of a vehicle controller are separated, and thereby, implementation of the modular design of control software is facilitated. The method realizes optimal torque distribution of the 4-wheel independent driving electric vehicle under the straight driving cycle, and thus, on the premise of satisfying the driving intention, the energy efficiency of a power assembly can be effectively increased, and meanwhile, it is guaranteed that power performance and braking stability of the vehicle meet the design indexes.

The invention discloses an electric-hydraulic composite braking system for an electric automobile and an optimization method of the electric-hydraulic composite braking system. The electric-hydraulic composite braking system for the electric automobile comprises a motor regeneration braking force module, a hydraulic braking force module and a composite braking force control module. The motor regeneration braking force module comprises two hub motors, a brake pedal position sensor, four wheel speed sensors, an automobile speed sensor, a super-capacitor, a two-quadrant DC-DC converter and a first ECU. The hydraulic braking force module comprises an oil pump motor, a hydraulic oil pump and a second ECU. In the traveling process of the automobile, through detection of the automobile speed and the wheel speed of automobile traveling and brake pedal position signals, the composite braking force control module controls the distribution ratio between the motor regeneration braking force module and the hydraulic braking force module. Meanwhile, through multi-objective optimization conducted on the electric-hydraulic composite braking system, the braking pedal feeling and motor recovered energy serve as objects, and under the ECE laws and regulations, the relatively high energy recovery rate and the proper brake pedal feeling are obtained.

The invention relates to a distributed type electronic hydraulic brake system using isolating valves and belongs to the field of active safety of automobiles. The distributed type electronic hydraulic brake system comprises four brake actuating mechanisms, four brakes, two isolating valves, four actuating mechanism controllers, a brake pedal, one pedal sensor, a line control brake controller, a bus and a brake pipeline. Each brake actuating mechanism is composed of a motor and a hydraulic cylinder. Each hydraulic cylinder is provided with two oil outlets, one of the two oil outlets is connected with the brakes, and the other oil outlet is connected with the isolating valves. One of the two isolating valves is used for being connected with the brake actuating mechanisms of two front wheels, and the other isolating valve is used for being connected with the brake actuating mechanisms of two rear wheels. The distributed type electronic hydraulic brake system using the isolating valves can improve reliability.

The invention discloses a vehicle bend braking stability step control system which implements the step control on a total braking force Fx during the vehicle bend braking and the distribution of the total braking force on a front wheel and a back wheel by a braking force adjusting device according to different time points during the braking process of turning radius, vehicle speed and road attachment conditions during the vehicle bend braking. The upper limit of the total braking force Fx and the resultant force of a total lateral force Fy (equal to vehicle centrifugal force) form a vehicle limit adhesion force. The slip ratio of each wheel is controlled so as to maintain the total braking force Fx within the upper limit. Thus, the vehicle adhesion force is controlled within the limit adhesion force. When the vehicle speed during the braking process is lowered continuously, the centrifugal force is reduced continuously. The adjustment of the control system is not frequent according to a discipline that the upper limit of the total braking force of the vehicle changes with the braking time. The target slip ratio of the wheel at different time points is regulated according to time segments so as to ensure that the vehicle adhesion force during the braking process is within the limit adhesion force, so that the braking stability of the vehicle bend is guaranteed.

The invention discloses a regenerative braking system for a wheel hub motor-driven automobile. A motor braking and hydraulic braking composite mode can be realized to enhance the braking efficiency. The invention further provides a regenerative braking method for the wheel hub motor-driven automobile. The regenerative braking method for the wheel hub motor-driven automobile comprises the followingsteps of step 1, obtaining total braking torque needed by braking according to pedal displacement, distributing the total braking torque to a front axle and a rear axle according to a fixed proportion and uniformly distributing braking forces of the front axle and the rear axle to corresponding wheels, wherein the motor braking force and hydraulic braking force of each wheel are independently controlled; step 2, obtaining the rotation speed of a wheel hub motor according to the current wheel rotation speeds and calculating maximum braking torque Tm, which can be provided by the wheel hub motor; and step 3, when the desired braking forces Trep of the wheels are less than 0.8 Tm, executing a pure motor braking mode; when the desired braking forces Trep of the wheels are not less than 0.8 Tm, executing a composite braking mode of the wheel hub motor braking and hydraulic braking; and after the automobile speed is decelerated to 10 km/h, entering a pure hydraulic braking mode, closing a wheel hub motor regenerative sub system and opening a pressure increasing valve to enhance the braking efficiency.

The invention provides a method for optimizing braking force distribution in an electro-hydraulic compound braking system, belongs to the technical field of electro-hydraulic compound braking and relates to the field of swarm intelligent algorithms. According to the requirements of pure electric vehicle of different types or pure electric vehicles of a certain type for the braking stability and braking energy recycling efficiency, the contradictory relation of the braking stability and the braking energy recycling efficiency to a certain extent in an electromechanical hybrid braking area is comprehensively considered; and the parameter of the electro-hydraulic compound braking system is optimized through an improved particle swarm algorithm with the high global searching ability, an adaptability function serving as the optimizing judgment standard is established, and the historical global optimum value of a particle swarm is obtained and serves as the parameter meeting the needed electro-hydraulic compound braking system. The algorithm is simple, the global searching ability is high, the convergence rate is high, the braking stability of vehicles in the braking process is guaranteed, and meanwhile braking energy of a motor is recycled to the largest extent.

The invention discloses a portable dynamic detection method and system for braking performance of automobile wheels. The method comprises steps as follows: three-dimension acceleration of the wheels is sensed by triaxial accelerometers of wheel testing modules, and a braking detection signal is sensed by a pedal force sensor; the signal is output by a wheel tangential acceleration sensor, wheel signal characteristic quantity is extracted through wavelet transformation noise reduction treatment and short-time Fourier transform operation, and rotating period, rotating frequency and angular velocity of the wheels are obtained; braking distance, speed and initial braking speed of an automobile body as well as wheel braking deceleration are calculated according to angular velocity parameters ofthe wheels; inequality of braking deceleration balance of the left and right wheels is calculated according to wheel braking deceleration parameters; MFDD (mean fully developed braking deceleration)is calculated according to initial baking spedd and braking distance parameters of the automobile body; braking coordination time is calculated according to the braking detection signal and MFDD parameters. The system comprises the wheel detection modules, round movable hub catch plates, the pedal force sensor and an in-vehicle central control module.

The invention discloses a lift type driving device for an elevator, and relates to the technical field of elevator equipment. The lift type driving device includes a motor, a bearing plate and a magnetic powder brake. An output shaft of the motor is fixedly provided with a driving pulley, and the motor is fixedly installed on the lower surface of the bearing plate through a first connecting plate;a connecting cylinder penetrates through the middle part of the bearing plate, and a first through hole is formed in the connecting cylinder; and a connecting ring is fixedly installed on the top endface of the connecting cylinder, and a second through hole is formed in the connecting ring. According to the lift type driving device, the driven pulley is driven to drive brake shaft sleeves of a step sleeve, the connecting cylinder, the connecting ring and the magnetic powder brake to rotate, so that a screw nut rotates and rises and falls in the axial direction of a screw rod; finally, the brake of the screw nut on the screw rod is realized by controlling the magnetic powder brake; and due to the process, the lifting and falling and brake stability of the elevator driving device are effectively ensured, the risk of people riding is reduced, and the comfort of people riding is improved.

The invention discloses a new energy automobile regenerative braking force distribution method and a new energy automobile, and relates to the technical field of new energy automobile braking. The regenerative braking force distribution method for the new energy automobile comprises the steps that the total braking forces are distributed to front wheels and rear wheels, more total braking forces are distributed to the rear wheels when the braking strength is small, and the total braking forces are distributed to the front wheels and the rear wheels according to an ideal braking force distribution mode when the braking strength is large; the rear wheel total braking force obtained through distribution is divided into the rear wheel friction braking force and the motor braking force, when the motor can meet the braking requirement, the rear wheel total braking force is distributed to the motor as much as possible, and when the motor cannot meet the braking requirement, the rear wheel friction braking force is used for compensation. When the regenerative braking force is distributed through the regenerative braking force distribution method for the new energy automobile, the braking capacity of the motor can be brought into full play on the basis that the good braking feeling is guaranteed, and efficient braking energy recovery is achieved.

The invention discloses a new energy automobile regenerative braking force distribution method and a new energy automobile, and relates to the technical field of new energy automobile braking. The method comprises the following steps: a first braking strength limit is determined according to the current braking capacity of a motor, and a second braking strength limit is determined according to braking efficiency and braking stability; a regenerative braking force distribution strategy is determined according to the magnitude relation between the braking strength and the first braking strengthlimit and the second braking strength limit, and the total braking force is distributed to rear wheels as much as possible; and the rear wheel total braking force obtained through distribution is divided into the rear wheel friction braking force and the motor braking force, when the motor can meet the braking requirement, the rear wheel total braking force is distributed to the motor as much as possible, and when the motor cannot meet the braking requirement, the rear wheel friction braking force is used for compensation. According to the method, the total braking force can be distributed tothe braking force of the rear wheels according to the maximum braking force provided by the motor, so that the braking capacity of the motor is brought into full play, and efficient braking energy recovery is realized.

The invention discloses a braking system applied to a college student equation and a working method of the braking system. The braking system comprises an adjusting base and a braking module. The adjusting base is mounted on the frame; the brake module and the acceleration module are installed on the adjusting base side by side. The brake module comprises a brake pedal, a brake adjusting motor, a transmission flexible shaft, a threaded rod, a front brake oil cylinder U-shaped fork, a brake pedal, a rear brake oil cylinder U-shaped fork and a brake oil cylinder. The middle of the threaded rod is rotationally connected to the bottom end of the brake pedal. Nuts are screwed to the two ends of the threaded rod. And the outer sides of the two nuts, the front brake oil cylinder U-shaped fork and the rear brake oil cylinder U-shaped fork respectively form a revolute pair. And the front brake oil cylinder U-shaped fork and the rear brake oil cylinder U-shaped fork are respectively connected with pistons of the two brake oil cylinders. Through cooperation of the motor and the flexible shaft, the threaded rod serving as a lever is driven to rotate, the ratio of input oil pressure of front and rear wheel brakes is adjusted through rotation of the threaded rod, and flexible control over braking force of front and rear wheels is achieved.