This negative-pressure type booster device improves operation feeling for a driver at the time of a sudden braking operation. A valve body is provided with a flange part which extends in the radially outward direction from a front section of the valve body, and a plate is provided with a locking part which comes into contact with the flange part so as to restrict a movement in the axially forward direction relative to the valve body.

A servo brake includes a thrust unit connecting a servo-piston to a primary piston in an actuation direction. The thrust unit includes a plunger with a front end in the form of a spherical cap and pressed in a cup of the primary piston and a rear end that includes a ball joint. A bearing has a base pressed on a reaction disc and a sleeve that receives the ball joint of the plunger.

A servo brake includes a thrust unit connecting a servo-piston to a primary piston in an actuation direction. The thrust unit includes a plunger with a front end in the form of a spherical cap and pressed in a cup of the primary piston and a rear end that includes a ball joint. A bearing has a base pressed on a reaction disc and a sleeve that receives the ball joint of the plunger.

An electromechanical brake booster is provided for a braking system of a vehicle, having a valve body and an input rod, the valve body, to which at a displacement motion in a brake application direction has been imparted, being displaceable up to a differential travel equal to a limit differential travel with reference to the input rod, and then a co-displacement motion in the brake application direction being impartable to the input rod if the co-displacement motion is acted against at most by a retention force below a predefined threshold value, and at least one buffer element being disposed on the input rod and/or on the valve body in such a way that if a retention force above the predefined threshold value acts against the co-displacement motion, the differential travel is increasable above the limit differential travel by way of a deformation of the at least one buffer element.

An electromechanical brake booster is provided for a braking system of a vehicle, having a valve body and an input rod, the valve body, to which at a displacement motion in a brake application direction has been imparted, being displaceable up to a differential travel equal to a limit differential travel with reference to the input rod, and then a co-displacement motion in the brake application direction being impartable to the input rod if the co-displacement motion is acted against at most by a retention force below a predefined threshold value, and at least one buffer element being disposed on the input rod and/or on the valve body in such a way that if a retention force above the predefined threshold value acts against the co-displacement motion, the differential travel is increasable above the limit differential travel by way of a deformation of the at least one buffer element.

A pneumatic booster capable of suppressing braking force from becoming excessive relative to an input force applied to a brake pedal. A valve mechanism (13) includes a poppet valve (14) movably attached to a small-diameter cylindrical portion of a valve body (6), an annular abutment portion formed on a plunger body of a plunger (20) to bring a variable-pressure chamber B into and out of communication with the atmosphere by unseating from and seating on the poppet valve, respectively, a movable seat member (29) movably guided by the valve body to bring a negative-pressure chamber A and the variable-pressure chamber B into and out of communication with each other, and a transmitting member (31) having one end abutting against the movable seat member and the other end disposed to surround a stepped piston of the plunger so as to be abuttable against a reaction disk (27).

A pneumatic booster capable of suppressing braking force from becoming excessive relative to an input force applied to a brake pedal. A valve mechanism (13) includes a poppet valve (14) movably attached to a small-diameter cylindrical portion of a valve body (6), an annular abutment portion formed on a plunger body of a plunger (20) to bring a variable-pressure chamber B into and out of communication with the atmosphere by unseating from and seating on the poppet valve, respectively, a movable seat member (29) movably guided by the valve body to bring a negative-pressure chamber A and the variable-pressure chamber B into and out of communication with each other, and a transmitting member (31) having one end abutting against the movable seat member and the other end disposed to surround a stepped piston of the plunger so as to be abuttable against a reaction disk (27).

A device for varying a pedal resistance of a hydraulic brake system includes at least one electroactive polymer actuator. The device further includes a reaction disc. The reaction disc has at least two polymer actuators. The at least two polymer actuators are independently controllable. Additionally, the at least two polymer actuators are arranged coaxially relative to one another.

A device for varying a pedal resistance of a hydraulic brake system includes at least one electroactive polymer actuator. The device further includes a reaction disc. The reaction disc has at least two polymer actuators. The at least two polymer actuators are independently controllable. Additionally, the at least two polymer actuators are arranged coaxially relative to one another.

An electromechanical braking device for a braking system including a master brake cylinder including an electric motor, an adjustable output rod, and a gear, the electric motor being connected to the output rod at least via the gear so that a power transmission path is present via which a motor output is at least partially transmittable to the output rod so that the output rod is adjustable, the electromechanical braking device including at least one elastic component situated within the power transmission path which is configured so that the at least one elastic component is not compressible below a control point of the electromechanical braking device, but during the occurrence of pressure peaks in the master brake cylinder which are above the control point of the electromechanical braking device, the at least one elastic component is compressible. Also described is a braking system for a vehicle.