Abstract: The present invention is directed to a brake control system, which includes wheel brake cylinders, a master cylinder, a reservoir communicated with the wheel brake cylinders, normally open solenoid valves disposed between the master cylinder and the wheel brake cylinders, respectively, normally closed solenoid valves disposed between the wheel brake cylinders and the reservoir, respectively, a hydraulic pump for supplying the brake fluid to a passage for connecting the master cylinder with the normally open valves, and an automatically pressurizing device (e.g., a vacuum booster with a changeover valve) which is provided for advancing the master piston irrespective of operation of the pump and the brake pedal to generate hydraulic braking pressure from the master cylinder.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A master cylinder (12) for use in a brake system (10). The master cylinder (12) has a housing (22) with a first (42) and second (44) pistons located in a bore (20) by first (46) and second (48) resilient members to define first (50) and second (52) chambers therein. The first (50) and second (52) chambers are respectively connected to a reservoir (32) to receive fluid and maintain a desired fluid level in the brake system (10) and to front (24,24′) and rear (26,26′) wheel brakes to supply pressurized fluid to effect a brake application. Fluid received from the reservoir (32) by [to] the second chamber (52) is controlled by a center port compensation valve (148). The center port compensation valve (148) has a head (126′) connected to a linkage member (98′) that joins a first retainer (94′) with a second retainer (96′) to cage the second resilient member (48).

Abstract: A motor vehicle brake system actuator has a pedal block with a brake pedal fixed thereon pivotably. A brake power booster with a two-part housing and with a main brake cylinder assembly unit is connected to the brake pedal for the admission of hydraulic power into the individual wheel brakes of the motor vehicle. The pedal block and the brake power booster housing bottom part facing the pedal block are made in one piece from plastic.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A vehicle motion control system which generates a minimized switching noise when a hydraulic pressure control valve is switched. The vehicle motion control system includes an automatic hydraulic pressure generator generating a hydraulic pressure irrespective of a brake pedal operation and a hydraulic pressure control valve adjusting the hydraulic brake pressure by opening or blocking a connection between the automatic hydraulic pressure generator and a wheel brake cylinder, and performs a motion control by controlling at least the hydraulic pressure control valve in accordance with the motion of a vehicle.

Abstract: A vehicle motion control device reduces noise resulting from operation of a vacuum booster when an automatic pressure control is performed by properly controlling the energization of a linear solenoid of a booster actuator. An automatic hydraulic pressure generator is controlled in accordance with the vehicle motion condition and a hydraulic pressure control valve device is controlled to perform the automatic pressure control. A target electric current of the linear solenoid for actuating the vacuum booster is instantaneously increased to a starting target value which corresponds to an electric current value immediately before starting the operation of the vacuum booster and which is less than a maximum value of the target electric current, and then is gradually increased approximately to the maximum value of the target electric current.

Abstract: A brake system for (10) a vehicle having a brake booster (14a) with an output put rod (152a) for providing a primary piston (310) in a master cylinder (12a) with an input force to pressurize fluid which is supplied to wheel brakes (10a) of a vehicle to effect a brake application in response to an operator input force. The master cylinder (12a) has a first housing (202a) with a bore (202a) therein for retaining the primary piston (310) in a first pressure chamber (212a). The bore (202a) has a first compensation passage (206a) connected to a fluid supply (204a) and an outlet port (218) connected to the wheel brakes (10a). The primary piston (310) has a first position of rest whereby the first pressure chamber (212a) is connected to a fluid supply (204a) through the first compensation passage (206a). The brake booster (14a) has a second housing (102,104) with an interior separated by a movable wall (122) into a front chamber (108) and a rear chamber (110).

Abstract: A brake control device includes a pressurization device having a first pressurization device for pressurizing the brake fluid supplied to wheel brakes in response to the driver's operation and a second pressurization device for pressurizing the brake fluid supplied to the wheel brakes independently of the driver's operation; a first detecting device for detecting a displacement of an input member of the pressurization device or an output pressure of the pressurization device; a second detecting device for detecting the condition of the vehicle; and a control device for memorizing relationships between a driving signal of the second pressurization device and the displacement of the input member or relationships between a driving signal of the second pressurization device and the output pressure of the pressurization device as control maps corresponding to the variety of the condition of the vehicle and for controlling the driving signal of the second pressurization device on the basis of the control

Abstract: A substantially constant brake assist gain is provided in a vehicle braking system having a vacuum booster providing braking assist to a brake fluid master cylinder in response to an operator input braking force, even though the gain of the booster falls off from its maximum value in a non-linear manner in a runout initiating portion of the working vacuum range near zero booster vacuum. A brake fluid pump, such as is used in an ABS/TCS modulator, is used to supplement the booster output as it falls so as to maintain a constant, linear brake system gain into runout. In the runout initiating portion of the working vacuum range, a runout assist gain is derived from stored data expressing booster assist gain as a function of booster vacuum, and a target wheel pressure is calculated from the derived runout boost assist gain and a corresponding change in master cylinder pressure.

Abstract: A detection switch is mounted on an input shaft through a clevis for detecting the operation of an automatic brake unit without the depression of a brake pedal. The detection switch may also be mounted on the brake pedal. The clevis and the brake pedal are connected together in a manner to permit a relative displacement therebetween through an operating stroke of the detection switch. When the brake pedal is depressed, the brake pedal is maintained at an advanced position relative to the input shaft, and the detection switch detects a retracting movement of the brake pedal with respect to the input shaft from the advanced position during an automatic brake operation. The arrangements allow the detection switch to be mounted on either the input shaft or the brake pedal, does not require design of a small size and facilitates the mounting of the detection switch.

Abstract: A brake pressure control device is described. The device includes a pneumatic brake booster which has at least two chambers that are separable from each other. At least one of the chambers can be operated as a low-pressure chamber and at least another one of the chambers can be oerated as a working chamber. The device further includes a master braking cylinder in which a master cylinder pressure is generated over the pneumatic brake booster, and a hydraulic unit, which is installed between the master cylinder and at least one wheel brake cylinder of at least one wheel. The hydraulic unit includes an arrangement of switchable valves as well as least one pump. A hydraulic boost of the brake pressure is achievable with the assistance of the hydraulic unit. A wheel brake cylinder pressure may be generated in the at least one wheel brake cylinder with the assistance of the hydraulic unit, the wheel brake cylinder pressure being greater than the master cylinder pressure.

Abstract: The invention relates to an electronically controllable brake booster with a vacuum chamber and a pressure chamber, which are separated from each other by a movable wall, a control valve arrangement which can be actuated by means of an electromagnetic actuation means, and by means of which a pressure difference between the pressure chamber and the vacuum chamber can be adjusted, with the control valve arrangement, as a function of a current flowing through the electromagnetic actuation means, assuming a holding position in which the current ranges between a higher value and a lower value without the control valve arrangement leaving the holding position, a first pressure changing position in which the current is higher than the higher value, and a second pressure changing position in which the current is lower than the low value, characterized in that upon a changeover of the control valve arrangement from the holding position into the first or the second pressure changing position, or upon a changeover from

Abstract: A braking system including a brake cylinder, a first hydraulic pressure source having a first pump device for pressurizing a working fluid, a second hydraulic pressure source operable in response to an operation of a brake operating member, to pressurize the fluid to a pressure higher than a value corresponding to an operating force of the brake operating member, and a brake-cylinder-pressure control device operable when the brake cylinder is disconnected from the second hydraulic pressure source, to control the pressure of the fluid pressurized by the first hydraulic pressure source, such that the fluid pressure in the brake cylinder is controlled to a value determined on the basis of the operating force, and wherein an emergency communication device is operated when at least one of the brake-cylinder-pressure control device and the first pump device fails to normally function, to hold the brake cylinder in communication with the second hydraulic pressure source.

Abstract: A brake system including a negative pressure booster, a master cylinder of tandem type and an intensifying arrangement. The intensifying arrangement defines an intensifying chamber disposed rearward of a primary piston, a pump for supplying a braking liquid to the intensifying chamber, and a reaction piston and a sleeve for controlling the pressure of the braking liquid which is supplied to the intensifying chamber. As a brake pedal is depressed and the intensifying arrangement is actuated, a sum of an urging force from the negative pressure booster and an urging force from the intensifying arrangement operates the primary piston to develop a master cylinder pressure. The sum is proportional to the input or a force depressing the brake pedal.

Abstract: A braking control apparatus for vehicles which is capable of generating a braking force in response to a pedal depression force to non-controlled wheels while continuing vehicle stability control. The apparatus generates a brake fluid pressure including a pedal input pressure in response to the pedal depression force and a servo pressure in response to a fluid pressure introduced from a pressure apply unit. A fluid pressure control apparatus supplies brake fluid pressure, an electric control unit controls the braking force of each wheel by driving, and a pedal input pressure estimate portion estimates the pedal input pressure. The electric control unit controls the braking force of the non-controlled wheels during vehicle stability control based on the pedal input pressure estimated by the pedal input pressure estimate portion of the electric control unit.

Abstract: The pump is connected on its delivery side through an auxiliary passage to a primary passage connecting the master cylinder and brake cylinder to each other, and a pressure control valve is provided in a portion of the primary passage between the master cylinder and a point of connection thereof to the auxiliary passage. The pressure control valve releases working fluid from the pump to the master cylinder when delivery pressure of the pump is higher than the master cylinder pressure by more than a predetermined amount, and the pump is activated when the fluid pressure generated in the brake cylinder is required to be higher than the master cylinder pressure, during brake operation.

Abstract: A braking pressure boosting device is suggested, in particular for automotive vehicles, which includes a boost sensor for sensing or identifying the point of maximum boosting of the braking pressure boosting device. By using the boost sensor, ad signal is generated reporting the point of maximum boosting. This invention permits the manufacture of high-performance braking force boosting devices requiring minimal space and opens up new potential for economizing.

Abstract: In order to provide a brake booster negative pressure controller which reduces deterioration in the fuel consumption due to operation for closing a throttle to assure a brake booster negative pressure while assuring the braking capability required according to driving conditions and can safely assure a braking capability even when a failure occurs in a negative pressure sensing system, said brake booster negative pressure controller comprises a brake booster for assuring a master vac negative pressure by using a negative pressure of an engine, a throttle valve whose opening angle can be operated independently from the stroke of an accel pedal, and a brake operation sensing means, wherein the negative pressure controller has a speed sensing means and a means for closing the throttle valve by a predetermined amount when the vehicle speed sensed by the vehicle speed sensing means is equal to or higher than a predetermined value and application of the brake is sensed by the brake operating sensing means.

Abstract: In a fluid pressure booster, an input rod 7 and a valve member 6 are stroked forward during the operation so as to cause a control valve to be switched over. The atmosphere is introduced into a working pressure chamber 30 via the control valve 41 and a power piston 19 then operates to make a negative pressure booster 1 produces an output from a output rod 13. As the atmosphere in the working pressure chamber 30 acts backward on a control piston 25 at this time, the valve member 6 will not be stroke further. However, the output rod 13 is continuously stroked forward and kept producing the output. Due to the stop of stroke of the valve member 6, the stroke of the input rod 7 is suppressed and set at an extremely short stroke. When the negative pressure falls, the negative pressure booster 12 produces an output from the output rod 13 since the input rod 7, the valve member 6 and the output rod 13 integrally give a stroke forward.

Abstract: A counter-force mechanism (37), which produces a counter force when a brake booster is operated, is made up of an input-side member (38) slidably disposed within a valve body (3), a second constant-pressure chamber (39) formed on the rear side of the input-side member and into which a pressure is introduced from a constant pressure chamber (A), and a second constant-pressure chamber (39) formed on the front side of the input-side member and into which a pressure is introduced from a variable pressure chamber (B). The counter force from the counter-force mechanism (37) is reduced by an orifice passage (43) as a counter-force reducing means in rapid operation of the brake.

Abstract: A braking force control apparatus adapted to change a magnitude of a braking force produced in response to a braking operation based on a condition of the braking operation, and control a braking force in an appropriate manner meeting an operating feeling of a vehicle operator. The braking force control apparatus performs either a normal control to produce a braking force by a braking operation or a brake-assist control to produce an increased braking force larger than the braking force produced during the normal control. In the apparatus, a stroke sensor (299) detects a stroke amount (L) of a brake pedal (202). When a stroke amount (L) of the brake pedal (202) detected at a predetermined time (TST) after the normal control is changed to the brake-assist control is below a predetermined value (&agr;), the apparatus determines that a brake releasing operation is intended by the operator, and terminates the brake-assist control.

Abstract: A fuel control system for a cylinder injection type internal combustion engine which can avoid frequent changeover of engine control mode and ensure a sufficient vacuum level for a brake operating pressure while protecting against degradation combustibility and fuel-consumption performance of the engine without resorting to additional provision of a special circuit or device. The system includes an intake air flow sensor (2) for detecting an intake air quantity (Qa) fed to an internal combustion engine (1) for thereby outputting a corresponding information signal, a crank angle sensor (5) for detecting a rotation speed (rpm) (Ne) of the engine (1) and a crank angle thereof to thereby output a corresponding information signal (SGT), and a pressure sensor (17) for detecting a brake operating pressure (PB).

Abstract: A pressure generator having a more efficient design and simple construction, and providing improved assembly efficiency and reduced cost includes a housing, a power piston which divides the inside of the housing into front chambers and rear chambers, an input member, a valve mechanism, an output rod, an auxiliary movable wall, an auxiliary variable pressure chamber, an electromagnetic valve unit, a master cylinder and a piston. The auxiliary variable pressure chamber is bounded by an auxiliary movable wall and a first movable wall.

Abstract: A brake power booster for automotive vehicles includes a control valve that is operable by an electromagnet irrespective of an actuating rod displacing a valve piston, the electromagnet actuating a third sealing seat which permits ventilation of the working chamber. The valve member of the control valve has passages which allow a pneumatic pressure compensation. To eliminate a pneumatic force component which counteracts the force generated by the electromagnet, the passages are provided radially outside the area delimited by the electromagnetically operable sealing seat on the sealing surface of the valve member.

Abstract: A brake system for motor vehicles with an adjustable pneumatic brake force booster includes a control valve which can be actuated by an electromagnet independently of the driver's actions. A brake pressure controller generates signals which serve to actuate the electromagnet. In order to be able to implement a quick-action, low-noise pressure regulating system at low cost, the brake pressure controller (8) is formed by connecting in parallel an electromagnetic control circuit (60) that processes the nominal brake pressure signal (Pnominal) into a first current value (IA) and a regulating circuit (70) that processes a control difference (&Dgr;P) formed from the nominal brake pressure signal (Pnominal) and the actual pressure signal (Pactual) into a second current value IB, with the output variable (Inominal) of the brake pressure controller (8) being formed by adding together the two current values (IA, IB).

Abstract: When a stroke speed exceeds a reference value of a stroke speed threshold value, a solenoid is energized to tract an armature, thereby opening an atmospheric valve independently of the position of a plunger. Consequently, power pistons, together with an output rod, are moved forward by a thrust corresponding to a pressure difference between a constant-pressure chamber and a variable-pressure chamber to perform a full-power braking operation. A reaction-adjusting mechanism contributes to an improvement in safety by functioning in such a way that when the part of the reaction force from the output shaft that is transmitted to an input rod reaches a predetermined value, a boosting ratio is increased, so that the reference value of the stroke speed threshold value can be set high to prevent unnecessary braking.

Abstract: The invention relates to a vehicle brake system of a motor vehicle, with an electronically controllable brake booster, comprising a vacuum chamber and a pressure chamber which are separated from each other by a movable wall, a control valve arrangement which can be actuated by an electro-magnetic actuator, wherein a pressure difference between the pressure chamber and the vacuum chamber is adjustable, with the movable wall changing its position as a function of the pressure conditions in the vacuum chamber and in the pressure chamber, thereby actuating a master cylinder, with the electromagnetic being supplied with current signals by an electronic control unit during operation, which the electronic control unit generates as a function of driving dynamics conditions or external influences, characterised in that upon the presence of certain driving dynamics conditions or external influences, or combinations thereof which render the actuation of the master cylinder necessary with a predetermined probability with

Abstract: A pedal modifier regenerative braking system is provided for an electric or hybrid electric vehicle having regenerative braking system. The pedal modifier regenerative braking system provides a mechanism for superimposing on a traditional vacuum power hydraulic system a reduction in the energy introduced by the vehicle driver into the friction brake system by an amount that is a function of the vehicle braking provided by an electric motor in a regeneration mode.

Abstract: A vacuum servo apparatus in which, in a performance diagram having an input coordinate axis perpendicular to an output coordinate axis, the normal operation is represented by a first operating line and, after a plunger member is moved by a solenoid so that movement of the plunger member with respect to a transmission member is controlled, the operation is represented by a second operating line following additional jump biasing force to be supplemented and generated is appropriately set and an output of the apparatus is designed to be faster during the return stroke for straightforwardly reflecting the intention of the driver.