Sumitomo Electric Industries, Limited

Mazada Motor Corporation

Hideaki Fujioka

Koji Takata

Yoshio Katayama

Kazumi Yasuzumi

Takato Ohgaki

Koichi Hashida

Keisuke Miyoshi

Yukinori Nishiyama

Yoichi Miyawaki

Tatsuji Matsumoto

Hisaaki Yamaguchi

Toshiki Ikeda

Toru Nakaura

A solenoid controlled valve comprises a spool. One end side of the spool is slidably inserted into a first fluid chamber of a sleeve in a fluid tight condition. The other end of the spool is loosely inserted into a second fluid chamber. The spool with a stationary orifice is provided in an inlet path extending in axial direction. A spring for urging the spool and a movable core fixed to the spool, and a coil are provided. When electric current is supplied to the coil, the movable core is attracted against the spring force and the spool moves opposite to the urging direction of the spring, so that the external peripheral face of the spool closes the first port and the second port.

Solenoid controlled valve and antilock control apparatus using the same

An anti-skid control apparatus includes a fluid pressure control valve positioned between a master cylinder and a wheel cylinder of each wheel. The fluid pressure control valve controls the wheel pressure cylinder. A reservoir is provided for temporarily storing brake fluid expelled from the wheel cylinder during an anti-skid control. A pumpless fluid pressure control device is also provided for circulating brake fluid stored in the reservoir back to a master cylinder without using a pump. A flow control valve for maintaining a constant flow of brake fluid is positioned between the master cylinder and the wheel cylinder.

Anti-skid control apparatus using a pumpless fluid pressure control

An antiskid control device for use in a motor vehicle which can be changed over to 2WD and 4WD by a changeover member, comprising: a drive signal output member for outputting a drive signal indicating that the changeover member is set to one of 2WD and 4WD such that changeover between antiskid control for 2WD and antiskid control for 4WD is performed in accordance with the drive signal; and a drive mode judging member which detects from behaviors of wheels of the motor vehicle that an actual drive mode of the motor vehicle is 2WD when the drive signal indicates that the changeover member is set to 4WD; wherein when the drive mode judging member has detected that the actual drive mode of the motor vehicle is 2WD, antiskid control for 4WD is changed over to antiskid control for 2WD.

Antiskid control device with a drive made judging means for a part-time

A pedal stroke detector detects the degree of depression of a brake pedal of a master cylinder to determine a road surface friction coefficient. A wheel speed detector monitors the speed of each wheel of a vehicle. A vehicle body speed calculator estimates the vehicle speed from the wheel speed of each wheel and the degree of depression of the brake pedal as detected by the pedal stroke detector. A lock symptom detecting mechanism detects a lock symptom from the estimated vehicle body speed and wheel speed. When a lock symptom is detected, a memory stores the degree of depression. Subsequent movement calculations are based on the larger of the degree of depression for the instant operational cycle and the degree of depression stored in memory.

Anti-lock brake controlling apparatus

A traction control permit/prohibit determination apparatus has a traction controller which applies a traction brake pressure to a brake system provided on the drive wheel when spinning of the drive wheel is detected. The traction controller is set to an operation permit mode when the vehicle speed is in the low speed range, and set to an operation prohibited mode when the vehicle speed is in the high speed range. Also, the traction controller is set to an operation permit mode when the pad temperature is below a first predetermined temperature, and to an operation prohibited mode when the pad temperature is above a second predetermined temperature.

Traction control permit/prohibit determination apparatus

An antilock brake control apparatus is provided for adjusting the wheel cylinder pressure with actuators that include on/off-type valves. The antilock brake control apparatus includes wheel speed detectors for detecting the speed of each wheel, a wheel speed and estimated vehicle speed calculation device for calculating the wheel and vehicle behavior, and a locking symptoms detection device for detecting wheel locking symptoms and recovery from a wheel locking condition. A target pressure setting device for setting a target pressure, which is the estimated value of the wheel cylinder pressure during antilock brake control, based on a wheel cylinder pressure and a locking symptoms detection edge, is also provided. Further, a pressurization signal setting device for setting a pressurization signal used to drive the actuators based on the target pressure is provided. The antilock brake control apparatus reduces the effects of pressure pulsations caused by operation of the on/off valves and, thus, enables high precision wheel cylinder pressure control.

Antilock brake control apparatus for controlling wheel cylinder pressure

An estimated vehicle speed computing device computes an estimated vehicle speed based on a computed non-drive wheel speed and a computed drive wheel speed of the vehicle. A first computed vehicle speed is computed based on the drive wheel speed and a second computed vehicle speed is computed based on the non-drive wheel speeds. When the first computed vehicle speed increase more than a predetermined level, the second computed vehicle speed is employed as the estimated vehicle speed. Furthermore, when the second computed vehicle speed is greater than the drive wheel speed, a speed other than the second computed vehicle speed is employed as the estimated vehicle speed.

Estimated vehicle speed computing device

A braking control system is provided in which a braking force is controlled so that a braking effect corresponding to the human brake pedal input can be obtained by electronically controlling an auxiliary power other than a human power. The braking control system includes a current deceleration detection device that detects a current deceleration, an initial deceleration detection device that detects an initial deceleration at a human operation input start time, and a control target addition quantity setting device that sets up a control target addition quantity based on a signal of the human operation input quantity. A control target quantity device is also provided that sets up a control target quantity by adding the initial deceleration and the control target addition quantity, so that an optimum braking deceleration corresponding to a pedal stroke is obtained regardless of the magnitude of a car deceleration in a braking operation.

Deceleration feedback electronic control system for use in a brake system

The antilock brake control apparatus has a locking symptom detector for detecting a wheel locking symptom and a removal of wheel locking symptom. A microcomputer is provided for producing a depressurization signal in response to the detection of the wheel locking symptom until the removal of the wheel locking symptom, and for calculating, after a locking symptom is detected, a pressure difference between the current wheel cylinder pressure and the wheel cylinder pressure when a locking symptom is first detected to obtain a maximum pressure difference at a time when the removal of the wheel locking symptom is detected. The microcomputer further produces a slow pressurization signal in response to the removal of the wheel locking symptom and during an asynchronous state, in which a difference between the wheel speed and the estimated vehicle speed is more than a predetermined range, and a rapid pressurization signal in response to the establishment of the synchronous state, in which the difference is within the predetermined range, and until the wheel cylinder pressure is increased to gain a predetermined percentage of the maximum pressure difference.

Antilock brake control apparatus

An antilock brake control system with a learning and correction function includes a slippage detector for detecting a slip value representing the slipping of a tire to a road surface. The slip value is compared with a slip threshold, and a locking symptom signal is produced when the slip value exceeds the slip threshold. A brake pressure suppression starts when the locking symptom signal is produced. A slippage learning arrangement is provided for learning, during a learning period from the start of brake pressure suppression until the tire stabilizes, whether a maximum of the slip value during the learning period is within a predetermined range, is greater than the predetermined range, or is less than the predetermined range. The slip threshold is corrected such that when the maximum slip value is greater than the predetermined range, the slip threshold is decreased, and when the maximum slip value is less than the predetermined range, the slip threshold is increased.

Antilock brake control system with learning and correction function

Antilock wheel speed control device having first and second brake

A wheel speed control apparatus for controlling a braking force and/or a driving force transmitted to wheels maintains the difference between the peripheral speed of each of the wheels and the vehicle running speed or an inferred value thereof at a value approximating the optimum value. The apparatus includes a normal control that detects and controls the increase or incipient increase of the difference over the absolute value using a differential value of the difference and difference or the rotational speed of the wheels. An integrating control detects and controls the continuation for a certain period of slightly excessive tendency of the absolute value of the difference, by comparing with a predetermined threshold value one of values which is smaller than the value with which, when the differential value is zero, the normal control would determines the excessive different only with the absolute value.

Automotive wheel speed control

A brake control device in an antilock brake system is disclosed for automatically adjusting a valve according to a wheel brake locking symptom to reduce a fluid pressure in a brake cylinder and eliminating symptom of brake locking. The brake control device includes a microcomputer which has a step for outputting a pressure reduction signal K required to eliminate a locking symptom, and a detector for detecting a current brake cylinder pressure. The microcomputer further has a step for correcting the pressure reduction signal K based on the current brake cylinder pressure. Thus, a corrected pressure reduction signal K is used for reducing the brake cylinder pressure.

Brake control device in an antilock brake system

An antilock brake control system for a motorcycle having front and rear wheels includes detectors for detecting front and rear wheel velocities, and a calculator for calculating an estimated velocity of the motorcycle. The calculator also calculates a slippage of the front and rear wheels relatively to the estimated motorcycle velocity. The amount of slippage is corrected by a compensation amount determined by the detection of various situations such as presence and absence of antilock control applied to front or rear wheel and presence and absence of brake applied to front or rear wheel.

Antilock brake control system for a motorcycle

A traction control system, or an anti-lock brake system comprises a wheel behavior detecting system which comprises a coefficient calculating circuit for calculating, on the basis of output values from wheel speed detectors, a bad road coefficient A of representative of the road surface irregularity upon which the vehicle is moving, and a control variable filtering circuit for producing a filtered value Lm which exhibits a normal waveform when the bad road coefficient A is small and a filtered waveform when the bad road coefficient is great thereby keeping abrupt changes caused by the bad road from erroneously controlling the traction or antilock systems. With the wheel behavior detecting system used in the traction control system or the anti-lock brake system, a control command determining circuit responds to the output from the filtering circuit, that is, the control variable which has been modified, to determine the command necessary to control braking forces to be applied to the wheels.

Growing community of inventors

Itami, Japan

Hideaki Fujioka