Showing papers on "Dynamic braking published in 1996"

Cart retriever vehicle

Abstract: A vehicle for retrieving wheeled shopping carts in parking lots. The vehicle is an electric-powered vehicle with electronic remote control which allows one operator to use the device for retrieval of the wheeled shopping carts. The vehicle can be operated in a remote or manual mode. The vehicle includes a cart coupling means for securing the wheeled shopping carts to the vehicle. The coupling means includes two arcuate jaw members which surround the rear tube frame members of the shopping cart. A locking rod is pushed across one jaw member to secure the shopping cart to the coupler assembly. When operating in the remote control, the operator guides the vehicle with a remote transmitter. The remote transmitter transmits signals using a pulse code modulation system. The signals use a 400 Mhz. carrier for digital signals. The vehicle can likewise be operated in a manual mode. The vehicle provides a foot pedal seat and steering wheel for manual operation. The electric drive means for powering the vehicle includes dynamic braking and a parking brake. A controller controls the electric drive means providing speed control to allow for dynamic load compensation. The parking brake is actuated automatically when the vehicle has come to a stop or released automatically when motion is sensed.

Regenerative brake controller for controlling value of regenerative braking torque simulating engine braking torque

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. When the shift lever is in the engine braking range, the controller detects the shift lever position in this range, determines the target braking torque or target deceleration by referring to the map, and on the basis of the vehicle speed and the like immediately before the release of the accelerator pedal and the shift lever position in the engine braking range, and controls the vehicle components according to the determined target braking torque or target deceleration such that the regenerative braking torque corresponding to the engine braking torque is produced. In connection with the regenerative braking torque corresponding to the engine braking torque, the vehicle drivability can be improved.

Method and apparatus for controlling the brake system of motor vehicles with electric drive

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.

Engine compression braking apparatus and method

Abstract: A braking control for an engine permits the timing and duration of exhaust valve opening to be accurately determined independent of engine events so that braking power can be precisely controlled

Electromotive chain saw

Abstract: The chain of an electromotive chain saw is quickly stopped by the combined use of an electric brake and a mechanical brake when a trigger member is turned off. The rear end of a brake band disposed to tighten a brake drum by operating a hand guard is secured to a bent rod. When the trigger member is released, the brake band is normally tightened around the outer periphery of a brake drum by the urging force of a coil spring. When the trigger member is released, a circuit provided with a brake winding is closed, thereby applying a dynamic braking force. When the dynamic brake force is applied, a centrifugal clutch is released quickly and the speed of stopping the brake drum is accelerated.

Regenerative braking control system for electric vehicle

Abstract: A regenerative braking control system for an electric vehicle which can be driven by operating an electric motor with electric energy supplied from an electric energy supply source mounted on the vehicle. A control unit (7) is designed so that regenerative braking force of the electric motor (2) is controlled in accordance with an inclination detected by an inclination detecting unit (28). This has made it possible to provide the electric vehicle with improved drivability and running performance.

Regulating braking forces at individual operable motor vehicle braking systems

Abstract: A desired yawing angle speed is determined, depending on the speed of the vehicle and the steering angle set by the driver. This is compared with the actual yawing angle speed. Based on the resulting deviation of these values, an auxiliary yawing moment in computed, which is realized by an individual control of the braking systems.A correction of the desired yawing angle speed computed in the reference model results, based on the determined float angle speed (beta). The corrected desired yawing speed is applied based on the further computation. The computed auxiliary yawing moment is corrected based on the determined float angle speed.

Electronic braking system for road vehicles operating with a trailer

Abstract: A trailer braking control system for incorporation into the braking equipment of a towing vehicle for providing a trailer braking command signal which is also regulated as to balance the braking between the towing vehicle and the trailer through the assessment of forces (Fv, Fh) in the coupling between the two vehicles. The assessment is made indirectly and is calculated from forces measured in the suspension components of at least two axles of the towing vehicle (Ff, Fr) and the changes occurring therein during braking (dFf, dFr).

Control method for antilock braking systems with stress sensor and measurement device of wheel operating force

Abstract: An antilock braking system employing stress sensors installed in the wheel axle structure of a motor vehicle. The stress sensors measure a road surface frictional force and a braking torque. A parameter M is calculated from these measured values. An ABS control terminates a braking pressure reduction process in accordance with the change in the parameter M. Thereby, the system can preclude the locking of the wheel of the motor vehicle even when the brake is suddenly applied, can prevent the braking pressure reduction from being over controlled, and makes possible to minimize the braking loss.

Brake operation simulator for automobile servo-assisted braking system

Abstract: The brake operation simulator (10) is used with the master braking cylinder (12) of a vehicle braking system with servo-assisted braking and has a slider (48) displaced against the force of a simulation spring element (58,60) in the direction of the master braking cylinder piston (34), together with the brake operating element(38) The coupling between the brake operating element and the slider is released when the brakes are operated manually upon failure of the hydraulic pump for the servo-assisted braking

Infinitely variable engine compression breaking control and method

Abstract: A control for operating an engine (30) in a braking mode of operation includes an actuator (110) engageable with an engine exhaust valve (40). A braking magnitude is selected from a continuous range of braking magnitudes between minimum and maximum levels and turn-on and turn-off points for the actuator (110) are established from the selected braking magnitude. The actuator (110) is operated in accordance with the turn-on and turn-off points to cause the engine (30) to develop the selected braking magnitude.

Control method for antilock braking systems with stress sensor

Abstract: An antilock braking system using stress sensors installed in the wheel axle of a motor vehicle. The stress sensors measure a road surface frictional force, a vertical load, a road surface friction coefficient, a braking torque, and a side force. An arithmetic calculator calculates a parameter value M from these measured values. An ABS controller controls movement process toward a braking pressure reduction mode in accordance with the change in the value M. Thereby, the system can preclude the locking of the wheel of the motor vehicle even when the brake is suddenly applied.

Automobile engine brake or retarder control system

Abstract: the control system determines the braking force provided by the engine brake or retarder in dependence on the difference in the rotation between the braked wheels and the non-braked wheels. The braking force is reduced when the difference in the wheel rotation rates exceeds a value which is below the threshold value used for activating anti-locking braking regulation. Pref. the reduction in the braking force is defined by the differential of the difference in the wheel rotation rates, with stepped reduction of the braking in successive cycles.

Two-wire brushless dc motor control system

Abstract: A two wire, brushless, d.c. motor power control system employs a rechargeable d.c. power source (e.g. a battery or a capacitor) to provide power to the commutation position sensing electronics, and commutation logic during dynamic braking and also if desired, during motor start-up after stopping or reversing direction. Current limiting is provided by sensing the two-wire motor current and using the communicating logic to modulate the turn-off/turn-on time of the communicating switches.

Braking force control system for an automotive vehicle

Abstract: The present invention is directed to a braking force control system capable of generating a first braking force and a second braking force that is a supplement to the first braking force. The first braking force is generated in response to the operation of the brake pedal. The second braking force is generated when the operation speed of the brake pedal is more than the threshold value. The operation stroke sensor detects the operation stroke of the brake pedal as the operation stroke data. The timer detects the operation time of the brake pedal as the operation time data. The operation speed of the brake pedal is calculated on the basis of the operation stroke data and the operation time data in the electric controller. The RAM of the electric controller memorizes operation stroke data and operation speed data from a plurality of operations. The threshold value is calculated on the basis of the plural operation stroke data and the plural operation speed data. In the electric controller the threshold value is then compared with the operation speed of the brake pedal.

Process and apparatus for controlling the brake system of a vehicle

Abstract: The onset and the end of the braking action, especially the braking action of the component vehicles of a combination vehicle, are determined on the basis of the course of the deceleration of the vehicle. On the basis of the values found for the onset and end of the braking action, the hysteresis between the component vehicles is compensated, so that the braking action begins and ends at essentially the same time at all the wheel brakes.

Wheelchair dynamic braking system

Abstract: An automatic braking system for wheelchairs which prevents rearward, downhill motion of wheelchairs while having no effect on horizontal or uphill motion. The braking system is made up of circular ratcheted plates which are attached to the axles of the driving wheels of the wheelchair and L-shaped members slightly in front of and beneath the ratcheted. The L-shaped members are rotatable about axles located in their angles. The long leg of an L-shaped member is directed downwardly by gravity and maintains the short leg in a substantially horizontal position. The short leg forms a pawl which engages the ratchets of the plate when the wheels start to roll backwards when the wheelchair is directed upwardly, thus automatically stopping the wheelchair.

Braking device and method for providing a more constant braking force

Abstract: The invention relates to a method and apparatus for providing a more constant braking force. The braking device and method according to the invention slows a mass moving with an initial speed at the time the braking device is activated. Sets of braking elements (16) having more or fewer braking elements (18) are activated depending on the initial speed. The device and method minimize variations in average friction coefficient over wide ranges of initial speed, which are typical for many braking materials. The invention broadens the range of braking materials for use in braking high speed trains, and is particularly useful with carbon/carbon braking materials.

Automatic braking control device for vehicle

Abstract: An automatic-braking control system for a motor vehicle, wherein an obstacle ahead of the vehicle is sensed so as to automatically brake the vehicle. In a case where the vehicle has been brought into a substantially stopped state by the automatic braking, a braking force for keeping the stopped state of the vehicle is determined, and the vehicle is subjected to a braking control with the determined braking force. In a case where the vehicle has resumed its drive and has reached a vehicle speed of predetermined value, the braking force is released. Thus, the vehicle is permitted to be driven as intended by the driver thereof.

Hydraulic braking system with electronic braking pressure regulation

Abstract: A brake system with electronic braking pressure control, including a braking pressure generator, electrically operable hydraulic valves, and an electronic analyzing, is provided with an acoustic sensor which is used to determine the change-over behavior of the hydraulic valves for the approximate determination of the braking pressure prevailing in the braking pressure generator and/or in the wheel brakes. The measured pressure values, in the capacity of control quantities, are taken into account for braking pressure control or analyzed for monitoring purposes.

Regenerative braking process for electric vehicle

Abstract: The regenerative braking is controlled by computing the speed of displacement of the accelerator pedal (VAC) between two successive pedal positions of the pedal. When the pedal movement is outward (toward the slowing down position) a value for the electric braking torque (f(VAC)) is computed, on condition that the brake pedal has not been operated. The computed torque is a function of the speed of release of the pedal. The set value for the torque of the vehicle drive motor is altered to obtain the desired level of braking. The braking torque value is stored in memory for quick computation of adjustment to set value.

Vehicle ride stability regulation method

Abstract: The stability regulation method individually regulates the force exerted on the road surface by each wheel in dependence of the required braking, if the vehicle and the detected slew rotation of the vehicle, by individual control of the vehicle wheel brakes (36,38,40,42). The braking control signals are supplied to each of the wheel brakes for controlling their individual operation via an electromechanical braking system, with an electrical brake operator (44,46,48,50) at each wheel brake.

Braking device of electric vehicle

Abstract: PROBLEM TO BE SOLVED: To provide a braking device of an electric vehicle which can make the maximum regenerative energy available by controlling hydraulic pressure braking torque of each wheel separately. SOLUTION: Between a master cylinder 20 and a wheel cylinder 40-46 of each wheel, proportional control valve 110-120 is instal led which can reduce the master cylinder pressure proportionally. Therefore, the pressures of the wheel cylinders 40-46 can be controlled separately. When braking torques required for wheels are different from wheel to wheel, the master cylinder pressure is controlled for each wheel with the regenerative braking torque being kept the maximum and thereby braking torque required by each wheel can be applied to it. By this method, the maximum regenerative energy can be available.

Brake device of electromotive vehicle

Abstract: PROBLEM TO BE SOLVED: To prevent the uncomfortable vibration caused by the sudden change of the load of a motor at the start of regenerative braking, in an electromotive vehicle which performs regenerative braking preferentially to hydraulic braking. SOLUTION: The occurrence of vibration is prevented by gradually increasing the regenerated braking force from the preset regeneration initial value to the requested braking force without instantaneously increasing the regenerated braking force to the requested braking force at the start of braking, and the amount of shortage of the braking force in that while is compensated by hydraulic braking force. In case that the requested braking force is over the regeneration tolerable value, the increase of that regenerated braking force is limited at the point of time when the regenerated braking force reaches the above regeneration tolerable value, and the amount of shortage of braking force after that is compensated by hydraulic braking force.

Dynamic brake device of servo motor

Abstract: A dynamic brake device having a simple circuit construction for a servo motor. A PWM control circuit (1) of this dynamic brake device generates a brake signal which simultaneously closes all switching devices of either a first group (TRa, TRc, TRe) connected in parallel in opposite directions with first diodes or a second group (TRb, TRd, TRf) connected in parallel in opposite directions with second diodes. In this way, each phase of the servo motor is short-circuited to thereby form a closed circuit, power generated by the servo motor at the time of brake is consumed by an internal resistance for dynamic braking.

Method and device for controlling a vehicle braking system

Abstract: A method and a device for controlling the braking system of a vehicle, in particular in conjunction with brakes having electromotive brake application, the individual wheel brakes being actuated within the scope of a closed-loop control, which produces the same friction coefficient at the wheels. The wheel contact patch forces of the vehicle are determined indirectly from the braking forces detected at the individual wheel brakes.

Braking condition evaluation sensor for vehicle

Abstract: A braking condition sensor has a device to evaluate the fluctuations in resonance oscillations in the tyre of one car wheel and another device to determine the braking condition from these fluctuations at different times. The first device also uses signals from a wheel speed sensor and/or an acceleration sensor and/or a torque sensor and/or a strain sensor coupled to the wheel. The second device estimates the gradient of the friction coefficient at the tyre and also estimates the braking condition from the change in this gradient. The circuit contains a solenoid valve to generate resonance oscillations in the switching of the hydraulic circuit for the wheel.

Stabilised manual-braking control device for vehicle

Abstract: The vehicle ride-stability control system monitors the drift of the vehicle during braking and during cornering. The drift is corrected for by selective braking on the corresponding front and rear wheels. The braking force is derived either from a pressure store reservoir or is taken as part of the manual (foot) braking action. For manual braking control the stabilising braking action is applied if the foot brake pedal is applied at above a set force. The corrective braking system takes into account road grip and ensures a stable control for the vehicle.

Vehicle, particularly motor vehicle, braking device

Abstract: The braking device is operated by depression of the brake pedal (1), which cooperates with a piezoelement (2) for providing an electrical signal acting as a control voltage for the wheel braking cylinders (9) of each of the braked wheels. The control voltage is fed to a piezotranslator associated with each wheel braking cylinder via an electronic control unit (5), for regulation of the braking force to provide ABS braking.