Abstract: A vehicle brake device is provided with a hydraulic brake device for boosting by a booster device a braking manipulation force generated upon a braking manipulation, for applying a base fluid pressure generated in dependence on the boosted brake manipulation force, to wheel cylinders of wheels so that a base hydraulic brake force is generated on the wheels, and for driving a pump to generate and apply a controlled fluid pressure to the wheel cylinders so that a controlled hydraulic brake force is generated on the wheels; braking manipulation state detecting means for detecting the braking manipulation state; a regenerative brake device for causing an electric motor to generate a regenerative brake force corresponding to the braking manipulation state on the wheels driven by the electric motor; variation detecting means for detecting the variation of an actual regenerative brake force actually generated by the regeneration braking device; and brake force compensating means for generating the controlled fluid p

Abstract: A more reliable hydraulic brake device is proposed which is capable of regenerative cooperative control and eliminates wasteful consumption of electric power. In a hydraulic brake device capable of regenerative cooperative control, a hydraulic pressure adjusting device is provided to adjust the hydraulic pressure in the auxiliary hydraulic chamber to a desired value that is above the output hydraulic pressure value of the pressure adjusting valve. During regenerative cooperative control, the output hydraulic pressure of the pressure adjusting valve is supplied to the auxiliary hydraulic chamber as it is. During non-regenerative cooperative control the output hydraulic pressure of the pressure adjusting valve is increased corresponding to regenerative braking force and supplied to the auxiliary hydraulic chamber.

Abstract: A hydraulic booster is provided between a M/C pressure and a W/C pressure. The hydraulic booster is composed of a pump and an amplifying piston amplifying the brake fluid amount discharged from the pump. The brake fluid discharged from the amplifying piston is supplied to the W/C via a first pipeline. The brake fluid discharged from the pump is supplied directly to the W/C via a second pipeline. First and a second control valves select the first or the second pipeline as a pressurizing path to the wheel cylinder.

Abstract: It is aimed to improve reliability of a hydraulic brake device which is capable of regenerative cooperative control, and also to eliminate wasteful consumption of electric power. Hydraulic pressure supplied from a hydraulic pressure generating device is adjusted to a value corresponding to the brake operating force by a pressure adjusting valve. A master cylinder is activated under the hydraulic pressure supplied to an auxiliary hydraulic chamber. The output hydraulic pressure of the master cylinder and the pressure adjusting valve is supplied to wheel cylinders to impart braking force to vehicle wheels. A hydraulic pressure adjusting device is provided to adjust the hydraulic pressure in the auxiliary hydraulic chamber to a desired hydraulic pressure value that is above the output hydraulic pressure value of the pressure adjusting valve.

Abstract: In a braking pressure intensifying master cylinder, as an input shaft (53) travels forwards in a braking maneuver, a control valve (54) is actuated to develop fluid pressure according to the input in a reaction chamber (38) and a pressurized chamber (35). A stepped spool (45) as a part of the control valve 54 travels such that force produced by the fluid pressure and spring force of a spring (51) are balanced, whereby the stepped spool (45) can function as a travel simulator. By changing the pressure receiving areas of the stepped spool and/or changing the spring force of the spring (51), the travel characteristic of the input shaft (53) as the input side can be freely changed independently from the output side, without influence on a master cylinder pressure as the output side of the braking pressure intensifying a master cylinder (1). In addition, the master cylinder pressure can be intensified when necessary with a simple structure.

Abstract: The invention relates to a brake system including a brake booster. A pneumatic pressure operated brake booster VBB or a liquid pressure operated brake booster includes a valve mechanism which is urged by a force of depression applied to a brake pedal BP to switch a flow path to cause the brake booster to develop an output which depends on the magnitude of the force of depression. A solenoid SOL urges the valve mechanism in the same direction as or in the opposite direction from the force of depression. A controller ECU is responsive to a braking effort increase/decrease demand signal to increase or decrease the urging force which is applied by the solenoid to the valve mechanism, thus increasing or decreasing the output from the brake booster. An output from the brake booster can be freely controlled independently from the force of depression applied to the brake pedal in response to a braking effort increase/decrease demand.

Abstract: In a brake booster of the present invention, by depression of a brake pedal 3, an input shaft 4 travels to the left, a pedal input converter generates thrust, and a valve element 5a moves to the left. A valve passage 5a1 is shut off from a valve passage 5b1 and a valve passage 5a2 is connected to a valve passage 5b2 so as to develop output pressure Pr at an output port 5c of a control valve 5 because of the pressure of a pressure source. The output pressure Pr is supplied to a wheel cylinder 7, thereby actuating the brake. At this point, since the displacement of the input shaft 4 required for operating the control valve 5 is defined only by the converter 6, the input side is not affected by the brake rigidity of a circuit from the control valve 5 to the wheel cylinder 7. The output pressure Pr of the control valve 5 acts on the valve element 5a through a first reaction receiving portion 8 and is regulated to pressure proportional to the thrust of the converter 6.

Abstract: In a brake fluid pressure boosting device 1 of the present invention, by operation, an input shaft 4 is moves forward to rotate a lever 27 to actuate a control valve 8 so that the control valve 8 produce working fluid pressure corresponding to the input. The working fluid pressure is introduced into the power chamber 6. By this working fluid pressure, the primary piston 37 is actuated to develop master cylinder pressure. On the other hand, the fluid pressure of the power chamber 6 is introduced into the first annular groove 25 of the valve spool 10. By the difference between pressure receiving areas of the first annular groove 25, the valve spool 10 is subjected to rightward force. The position of the pivot of the lever 27 is fixed and the valve spool 10 is controlled in such a manner that the force applied to the valve spool 10 and the spring force of the spool return spring 32 balances with the input, thereby exhibiting the function as a stroke simulator.

Abstract: A hydraulic booster is provided between a M/C pressure and a W/C pressure. The hydraulic booster is composed of a pump and an amplifying piston amplifying the brake fluid amount discharged from the pump. The brake fluid discharged from the amplifying piston is supplied to the W/C via a first pipeline. The brake fluid discharged from the pump is supplied directly to the W/C via a second pipeline. First and a second control valves select the first or the second pipeline as a pressurizing path to the wheel cylinder.

Abstract: In a braking pressure intensifying master cylinder of the present invention, as an input shaft 53 travels forwards in a braking maneuver, a control valve 54 is actuated to develop fluid pressure according to the input in a reaction chamber 38 and a pressurized chamber 35. A stepped spool 45 as a part of the control valve 54 travels such that force produced by the fluid pressure and spring force of a spring 51 are balanced, whereby the stepped spool 45 can function as a travel simulator. By changing the pressure receiving areas of the stepped spool 45 and/or changing the spring force of the spring 51, the travel characteristic of the input shaft 53 as the input side can be freely changed independently from the output side, without influence on MCY pressure as the output side of the braking pressure intensifying MCY 1. In addition, the master cylinder pressure can be intensified when necessary with a simple structure.

Abstract: A master cylinder which includes a primary piston and a thrust piston disposed within a housing, and defines an intensifying chamber at a location rearward of the thrust piston. An input shaft has a front end which is disposed within the intensifying chamber. The thrust piston is formed with a communication path (discharge passage), and a control valve is disposed between the thrust piston and the front end of the input shaft to open or close the communication path (discharge passage). When the input shaft is driven forward under the inoperative condition shown and the pump is operated to introduce a discharge pressure from the pump into the intensifying chamber, a liquid pressure is generated in the intensifying chamber and drives the primary piston forward, generating a liquid pressure in a liquid pressure chamber. In this manner, a master cylinder can be provided which has a simple and inexpensive construction with a reduced number of parts and which is compact in size.

Abstract: In a brake fluid pressure boosting device 1 of the present invention, by operation, an input shaft 4 is moves forward to rotate a lever 27 to actuate a control valve 8 so that the control valve 8 produce working fluid pressure corresponding to the input. The working fluid pressure is introduced into the power chamber 6. By this working fluid pressure, the primary piston 37 is actuated to develop master cylinder pressure. On the other hand, the fluid pressure of the power chamber 6 is introduced into the first annular groove 25 of the valve spool 10. By the difference between pressure receiving areas of the first annular groove 25, the valve spool 10 is subjected to rightward force. The position of the pivot of the lever 27 is fixed and the valve spool 10 is controlled in such a manner that the force applied to the valve spool 10 and the spring force of the spool return spring 32 balances with the input, thereby exhibiting the function as a stroke simulator.

Abstract: In a brake apparatus of the present invention, as MCY pressure is developed by a master cylinder (MCY) 1 according to the forward movement of a primary inner piston 9, a pump of a braking force control device arranged between the MCY 1 and wheel cylinders (WCYs) sucks up hydraulic fluid from the MCY 1 to discharge the hydraulic fluid to the WCYs. Thus, WCY pressure controlled according to operational conditions of various modes is developed. The WCY pressure is supplied to a control pressure chamber 40 to act on a step 8e of a primary outer piston 8. The primary outer piston 8 moves relative to the primary inner piston 9 in such a manner that the force produced by the MCY pressure, the force produced by the WCY pressure, the spring force of a control spring 13, and the frictional force of fluid-tightly slidable portions of the primary outer piston 8 are balanced, whereby the pedal travel can remain the same as that in service braking mode.

Abstract: The invention relates to a brake system including a brake booster. A pneumatic pressure operated brake booster VBB or a liquid pressure operated brake booster includes a valve mechanism which is urged by a force of depression applied to a brake pedal BP to switch a flow path to cause the brake booster to develop an output which depends on the magnitude of the force of depression. A solenoid SOL urges the valve mechanism in the same direction as or in the opposite direction from the force of depression. A controller ECU is responsive to a braking effort increase/decrease demand signal to increase or decrease the urging force which is applied by the solenoid to the valve mechanism, thus increasing or decreasing the output from the brake booster. An output from the brake booster can be freely controlled independently from the force of depression applied to the brake pedal in response to a, braking effort increase/decrease demand.

Abstract: A brake system has wheel cylinders for producing a braking force in wheels using pressurized brake fluid transmitted through a main conduit from a master cylinder, a reservoir for storing brake fluid, a sideslip preventing device for when a sideslip state of the vehicle is detected supplying brake fluid to the wheel cylinder corresponding to a sideslip controlled wheel and producing a braking force in the sideslip controlled wheel, a first conduit used for supplying brake fluid from the reservoir to the wheel cylinders by the pump and a first valve for switching this first conduit between an open state and a closed state. The sideslip preventing device, when the sideslip state is detected during non-braking of the vehicle, makes the first valve open-state and thereby conducts supply of brake fluid through the first conduit from the reservoir to the wheel cylinder by a pump.

Abstract: Before a wheel to be controlled satisfies conditions to shift to ABS control, when a specified or larger deceleration is caused by applying a brake, a wheel for which the difference in rotational speed from that of a wheel having the maximum rotational speed as the reference is equal to or larger than a predetermined value is subjected to the brake pressure increase restraint. At this time, the magnitude of the estimated lateral acceleration value is determined, and when the vehicle is in a sharp turn, pressure increase rates of the inside wheels are set to be particularly small values.

Abstract: An antiskid control system executes a modified antiskid control which strengthens the tendency of the wheel to lock if a vehicle speed is under a predetermined speed and the vehicle is running on a road which has a low coefficient of friction. Antiskid control is also modified with respect to front wheels and is normal with respect to rear wheels in order to avoid an occurrence of vehicle spin. Further, antiskid control is modified with respect to either a front right wheel or a front left wheel. As a result, a stopping distance of the vehicle can be shortened while securing the steering stability of the vehicle.

Abstract: In a hydraulic servo unit comprising a cylinder and a piston slidably inserted therein, the cylinder chamber being divided by a piston portion into a rod-side cylinder chamber and a head-side cylinder chamber, a control apparatus for the hydraulic servo unit includes but is not limited to a first hydraulic line connecting the rod-side cylinder chamber with the hydraulic pressure source which supplies working fluid of a predetermined pressure, a second hydraulic line connecting the head-side cylinder chamber with the first hydraulic line through a first solenoid valve of duty-ratio-control, and a drain hydraulic line connecting the head-side cylinder chamber with drain through a second solenoid valve of duty-ratio-control.

Abstract: A speed control apparatus for a continuously variable speed transmission comprises ratio control units for controlling a speed reduction ratio and a manual value for selecting either a running range where engine power is transmitted to the wheels or a neutral range where the engine power is not transmitted to the wheels. The speed reduction ratio is controlled by the ratio control units so as to coincide with a reference speed reduction ratio corresponding to the vehicle speed detected by a speed sensor when the neutral range is selected by manual valve.

Abstract: In a continuously variable speed transmission having a hydraulic pump, a hydraulic motor, a hydraulic closed circuit hydraulically connecting the pump with the motor, a control apparatus has a slip sensor for detecting slip of the driving wheels and a hydraulic control apparatus for lowering hydraulic pressure in the hydraulic closed circuit in accordance with magnitude of the slip of the wheels in such a way that the driving force of the driving wheels is reduced so as to be less than a slip limit force, the slip of the driving wheels being increased when the driving force applied to the driving wheels exceeds the slip limit force.