Abstract: There is provided a booster of a braking force 1 which drives a master cylinder by boosting an operation force of a brake pedal 100 in accordance with a movement amount of an input member 4 that reciprocates by an operation of the brake pedal 100, including: the input member 4 of which one end is linked to the brake pedal 100, which is inserted and fitted to the inside of a control housing 3 installed in a housing 2, and which is provided to be freely relatively slidable in an axial direction; and damping members 22, 31, and 32 which are provided at a part at which the input member 4 and the housing 2 abut against each other, or at a position which can be linked or abut against a part of the input member 4, in which, when the input member 4 moves to return when releasing an operation of the brake pedal 100, when the input member 4 abuts against the housing 2, the damping members 22, 31, and 32 perform an impact absorbing and damping action.

Abstract: There is provided a booster of a braking force 1 which drives a master cylinder by boosting an operation force of a brake pedal 100 in accordance with a movement amount of an input member 4 that reciprocates by an operation of the brake pedal 100, including: the input member 4 of which one end is linked to the brake pedal 100, which is inserted and fitted to the inside of a control housing 3 installed in a housing 2, and which is provided to be freely relatively slidable in an axial direction; and damping members 22, 31, and 32 which are provided at a part at which the input member 4 and the housing 2 abut against each other, or at a position which can be linked or abut against a part of the input member 4, in which, when the input member 4 moves to return when releasing an operation of the brake pedal 100, when the input member 4 abuts against the housing 2, the damping members 22, 31, and 32 perform an impact absorbing and damping action.

Abstract: An object of the invention is to prevent abnormal noise from being generated when the pressure of brake fluid supplied to a brake caliper is reduced. A vehicle brake device includes first and second hydraulic brakes generating a hydraulic brake force and a regenerative brake generating a regenerative brake force and divides a braking force into the hydraulic brake force and the regenerative brake force. The vehicle brake device includes a regulating valve that is provided between the first and second hydraulic brakes and continuously regulates the flow rate of brake fluid flowing to the second hydraulic brake from the first hydraulic brake, and a pressure reducing valve that reduces the pressure of the brake fluid supplied to the second hydraulic brake. An opening of the regulating valve is continuously increased and the pressure reducing valve is opened, when the hydraulic brake force of the first hydraulic brake is reduced.

Abstract: There is provided a vehicle brake device that includes hydraulic brake means for generating a hydraulic brake force and regenerative brake means for generating a regenerative brake force and distributes the hydraulic brake force and the regenerative brake force for a driver-requested brake force. The hydraulic brake means includes a pressure reducing valve that reduces hydraulic pressure of wheel cylinders. The vehicle brake device includes hydraulic brake control means for maintaining the pressure reducing valve open while the driver-requested brake force is covered by only the regenerative brake force. The hydraulic brake control means does not open the pressure reducing valve when hydraulic pressure is present in the wheel cylinders.

Abstract: There is provided a vehicle brake device that includes hydraulic brake means for generating a hydraulic brake force and regenerative brake means for generating a regenerative brake force and distributes the hydraulic brake force and the regenerative brake force for a driver-requested brake force. The hydraulic brake means includes a pressure reducing valve that reduces hydraulic pressure of wheel cylinders. The vehicle brake device includes hydraulic brake control means for maintaining the pressure reducing valve open while the driver-requested brake force is covered by only the regenerative brake force. The hydraulic brake control means does not open the pressure reducing valve when hydraulic pressure is present in the wheel cylinders.

Abstract: An object of the invention is to prevent abnormal noise from being generated when the pressure of brake fluid supplied to a brake caliper is reduced. A vehicle brake device includes first and second hydraulic brakes generating a. hydraulic brake force and a regenerative brake generating a regenerative brake force and divides a braking force into the hydraulic brake force and the regenerative brake force. The vehicle brake device includes a regulating valve that is provided between the first and second hydraulic brakes and continuously regulates the flow rate of brake fluid flowing to the second hydraulic brake from the first hydraulic brake, and a pressure reducing valve that reduces the pressure of the brake fluid supplied to the second hydraulic brake, An opening of the regulating valve is continuously increased and the pressure reducing valve is opened, when the hydraulic brake force of the first hydraulic brake is reduced.

Abstract: A negative pressure booster according to the present invention is configured in such a manner that a vacuum valve seat member (30) does not move, a reaction disk (25) protrudes and comes into contact only with a reduced diameter portion (24a) of a spacer member (24) under an operation in which an input is equal to or smaller than a preset input. Accordingly, the servo ratio becomes the normal servo ratio. Under the operation in which the input exceeds the preset input, the vacuum valve seat member (30) moves rearward (input side) with respect to a valve body (4) by the pressure in a variable pressure chamber (9), and a reaction disk (25) is significantly protruded to come into contact also with an increased diameter portion (24b) in addition to a reduced diameter portion (24a).

Abstract: In a negative pressure booster of the present invention, a threshold line for starting a BA operation at a pedal step-in speed equal to or more than a predetermined speed is set, an inclination of the threshold line is set to a value equal to a servo ratio SR2 smaller than a servo ratio SR1 during a usual braking operation in a low input region (a small pedal step-in region) and is set to a value equal to the servo ratio SR1 during the usual braking operation in a high input region (a large pedal step-in region). That is, the threshold line for starting the BA operation is adjustable between the high input time and the low input time. Further, even when a brake pedal is stepped in at the step-in speed equal to or more than the predetermined speed in spite of a fact that the time when the braking is performed is not an emergency time, the BA operation is not performed and hence, an undesired BA operation can be prevented.

Abstract: A tubular member 18 is slidably fitted into a valve body, and is formed with a vacuum valve seat 21. The tubular member 18, a valve plunger 16 and the valve body 3 are maintained in their inoperative positions shown by abutment against a key member 13. A holder 14 is formed with a tapered surface 14a to assist in allowing an elastic deformation of a reaction disc 15. Immediately after the commencement of operation of a valve mechanism 7 as an input shaft 8 is driven forward, the input shaft 8 and the tubular member 18 are maintained in their inoperative positions until a rear end face of a variable pressure passage 28 abuts against the key member 13. The operating stroke of an input shaft 6 can be chosen to be less than the operating stroke of an output shaft 11 while preventing the jumping value from increasing to an excessively high value.

Abstract: In a negative pressure boosting device, a movable valve seat is air-tightly and slidably disposed in a concavity of a valve body. The movable valve seat and a valve element compose a vacuum valve. A servo ratio changing device includes a control spring compressed and disposed between the movable valve seat and the valve body. The servo ratio changing device is provided on a valve mechanism (the vacuum valve). During operation, the valve element comes in contact with the movable valve seat. The movable valve seat does not move in a low-input range so that the servo ratio is a relatively large ratio for the normal operation. In a high-input range, the control spring starts to be compressed to move the movable valve seat, thereby changing the servo ratio to a small ratio.

Abstract: A brake booster 1 includes a valve mechanism 6, and a solenoid 8 which operates the valve mechanism 6. When the solenoid 8 is energized, a solenoid plunger 26 and a valve seat member 11 move rearward relative to a valve body 3, whereby the valve mechanism 6 is operated to actuate the brake booster 1 without depressing a brake pedal. A core member 27 which forms a magnetic path for the solenoid 8 is disposed rearward of the solenoid plunger 26 so as to be movable axially of the valve body and so as to move in linked relationship with a valve plunger 13. The invention allows the size of the solenoid 8 to be reduced.

Abstract: During a normal brake operation, a brake reaction from a reaction disc is transmitted to a valve plunger through an outer plunger and an inner plunger. During an emergency brake operation, as a valve plunger is driven forward through a given stroke relative to a valve body, a tubular member retracts relative to the valve body. In a servo balance condition, which is reached subsequently, the valve plunger, retracts by an amount corresponding to the retraction of the tubular member, and the outer plunger abuts against a holder. A brake reaction from the reaction disc is transmitted to the valve plunger only through the inner plunger, allowing a booster ratio to be greater and a jumping quantity to be greater than during a normal brake operation. It is possible to increase an output from a brake booster 1 rapidly in immediate response to a quick depression of a brake pedal.

Abstract: A brake fluid pressure generating device includes a first valve element connected to an input shaft, a first force device connected to the first valve element to provide a counter force relative to a force applied to the first valve, a second valve element situated adjacent to the first valve element, a power cylinder unit actuated by the first valve, a second force device situated between a power cylinder unit and the second valve element to move the second valve element, and a third force device connected to the second valve element to provide a counter force relative to a force applied to the second valve. A master cylinder is connected to the power piston to generate a master cylinder pressure to thereby output a regulated control valve output pressure. A desired stroke characteristic of the brake can be obtained.

Abstract: A tubular member 18 is slidably fitted into a valve body, and is formed with a vacuum valve seat 21. The tubular member 18, a valve plunger 16 and the valve body 3 are maintained in their inoperative positions shown by abutment against a key member 13. A holder 14 is formed with a tapered surface 14a to assist in allowing an elastic deformation of a reaction disc 15. Immediately after the commencement of operation of a valve mechanism 7 as an input shaft 8 is driven forward, the input shaft 8 and the tubular member 18 are maintained in their inoperative positions until a rear end face of a variable pressure passage 28 abuts against the key member 13. The operating stroke of an input shaft 6 can be chosen to be less than the operating stroke of an output shaft 11 while preventing the jumping value from increasing to an excessively high value.

Abstract: In a negative pressure boosting device 1 of the present invention, a movable valve seat 28 is air-tightly and slidably disposed in a concavity of a valve body 4. The movable valve seat 28 and a valve element 12 compose a vacuum valve 15. The movable valve seat 28 and a control spring 29 compressed and disposed between the movable valve seat 28 and the valve body 4 compose a servo ratio changing means. The servo ratio changing means is provided on a valve mechanism (the vacuum valve 15). During operation, the valve element 12 comes in contact with the movable valve seat 28. However, the movable valve seat 28 does not move in a low-input range so that the servo ratio in this state is relatively large ratio i.e. the servo ratio for the normal operation. In the high-input range, the control spring 29 starts to be compressed to allow the movement of the movable valve seat 28, thereby changing the servo ratio to a small servo ratio.

Abstract: A brake booster 1 includes a valve mechanism 6, and a solenoid 8 which operates the valve mechanism 6. When the solenoid 8 is energized, a solenoid plunger 26 and a valve seat member 11 move rearward relative to a valve body 3, whereby the valve mechanism 6 is operated to actuate the brake booster 1 without depressing a brake pedal. A core member 27 which forms a magnetic path for the solenoid 8 is disposed rearward of the solenoid plunger 26 so as to be movable axially of the valve body and so as to move in linked relationship with a valve plunger 13. The invention allows the size of the solenoid 8 to be reduced.

Abstract: A brake system 1 of the present invention comprises a brake operating means 2 such as a brake pedal for carrying braking operation, a fluid variable stroke means 3 which variably controls the stroke of the brake operating means 2 by using fluid, and a braking force output means 4 which is actuated by the operation of the brake operating means 2 to produce braking forces. By manipulating the brake operating means 2, the braking force output means 4 performs the braking operation. The traveling rang of the brake operating means 2 i.e. the stroke can be changed variously by the fluid variable stroke means 3 using fluid. Since the stroke of the brake pedal can be changed as mentioned above, a proper pedal stroke can be obtained.

Abstract: During a normal brake operation, a brake reaction from a reaction disc 12 is transmitted to a valve plunger 15 through an outer plunger 17 and an inner plunger 18.

Abstract: A hydraulic-pressure counter-force mechanism 37 which produces a counter force when a brake booster is operated is made up of an input-side member 38 slidable 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 hydraulic-pressure counter-force mechanism 37 is reduced by an orifice passage 43 as counter-force reducing means in rapid operation for brake.

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.