A valve mechanism of this negative pressure type booster device has: a negative pressure valve seat provided on a valve body; an atmospheric valve seat provided on a plunger; and a valve part provided with a negative pressure valve section constituting a negative pressure valve together with the negative pressure valve seat and an atmospheric valve section constituting an atmospheric valve together with the atmospheric valve seat. The valve mechanism is provided with a tilting part which is provided on at least one of the valve body and the valve part and tilts the atmospheric valve section relative to a first plane formed when the negative pressure valve section and the negative pressure valve seat are brought into contact with each other to put the negative pressure valve in a closed state.

A pneumatic brake booster for motor vehicles, comprises a booster housing, the interior of which is separated into a working chamber and a low-pressure chamber by an axially movable wall that can be supplied with a pneumatic differential pressure; a control housing; and a control valve which controls a differential pressure between the working chamber and the low-pressure chamber. The control valve controls an airflow between the working chamber and the low-pressure chamber or a surrounding atmosphere. The control valve has a plate valve and a valve piston, a seal region of which can be sealingly placed on the plate valve and which can be moved in a stroke direction R. A fine and low-noise metering of the brake force is achieved by providing a throttle point between the valve piston and the plate valve for throttling the airflow dependent on the stroke.

A pneumatic brake booster for motor vehicles, comprises a booster housing, the interior of which is separated into a working chamber and a low-pressure chamber by an axially movable wall that can be supplied with a pneumatic differential pressure; a control housing; and a control valve which controls a differential pressure between the working chamber and the low-pressure chamber. The control valve controls an airflow between the working chamber and the low-pressure chamber or a surrounding atmosphere. The control valve has a plate valve and a valve piston, a seal region of which can be sealingly placed on the plate valve and which can be moved in a stroke direction R. A fine and low-noise metering of the brake force is achieved by providing a throttle point between the valve piston and the plate valve for throttling the airflow dependent on the stroke.

Methods and systems are provided for a pressure tapping device for a motor vehicle where a portion of the pressure energy generated at the fuel storage reservoir is transmitted to a working medium, physically separate from the fuel via the pressure tapping device. The pressure tapping device is fluidically coupled to a pressure actuator and enables the pressure operation via transmission of the pressure energy and adjustment of valves diverting flow from the fuel storage reservoir to the engine intake through the pressure tapping device.

Methods and systems are provided for a pressure tapping device for a motor vehicle where a portion of the pressure energy generated at the fuel storage reservoir is transmitted to a working medium, physically separate from the fuel via the pressure tapping device. The pressure tapping device is fluidically coupled to a pressure actuator and enables the pressure operation via transmission of the pressure energy and adjustment of valves diverting flow from the fuel storage reservoir to the engine intake through the pressure tapping device.

A brake booster for a vehicle is provided. The booster includes a casing formed by a combination of a front and rear shell. A diaphragm divides the casing into a constant and a variable pressure room. A circumference of a front side end seals a valve body combined with the diaphragm and a rear portion penetrates the rear shell. A high pressure air passage selectively provides high pressure air from the rear portion to the variable pressure room and a bypass passage selectively provides atmospheric air to the variable pressure room. A check valve provides high pressure air passed a turbo charger and an intercooler to the variable pressure room through the high pressure air passage. An input rod advances and retreats through an air valve of the valve body. An output rod delivers force based on displacement of the air valve and the diaphragm to a master cylinder.

A vehicle having a valve stop mode control unit configured such that an intake valve and an exhaust valve are stopped in a closed state during rotation of an output shaft, supply of fuel to an engine is stopped, a clutch is made to be in an engaged state, and pistons are driven by rotational forces from driving wheels through the output shaft. When there is a request for valve stop inertial running, a negative pressure is supplied to an intake passage by a vacuum pump.

A vacuum brake booster for a motor vehicle brake system, comprising a displaceable force input member that is coupled to or can be coupled to a brake pedal, a chamber arrangement arranged in a booster housing having at least one working chamber and at least one vacuum chamber, which are separated from one another via at least one movable wall, a control valve assembly that can be actuated by the force input member, and a force output member for transmitting an operating force to a downstream brake system. The at least one working chamber can be fluidically connected optionally to a negative pressure source or the atmosphere by way of the control valve assembly. The control valve assembly comprises a control valve housing, in which an actuating piston that is coupled with the force input member s displaceably arranged, and a first valve seat, and a second valve seat. Upon an actuation of the force input member, a throttle sleeve can be displaced from the initial position relative to the control valve housing by a predetermined functional path. During the displacement, the throttle sleeve is in abutment with the actuating piston such that a fluidic connection between the at least one working chamber and the ambient atmosphere by way of a throttle window is present. Upon exceeding the functional path, the throttle sleeve lifts off the actuating piston.

A vacuum brake booster for a motor vehicle brake system, comprising a displaceable force input member that is coupled to or can be coupled to a brake pedal, a chamber arrangement arranged in a booster housing having at least one working chamber and at least one vacuum chamber, which are separated from one another via at least one movable wall, a control valve assembly that can be actuated by the force input member, and a force output member for transmitting an operating force to a downstream brake system. The at least one working chamber can be fluidically connected optionally to a negative pressure source or the atmosphere by way of the control valve assembly. The control valve assembly comprises a control valve housing, in which an actuating piston that is coupled with the force input member s displaceably arranged, and a first valve seat, and a second valve seat. Upon an actuation of the force input member, a throttle sleeve can be displaced from the initial position relative to the control valve housing by a predetermined functional path. During the displacement, the throttle sleeve is in abutment with the actuating piston such that a fluidic connection between the at least one working chamber and the ambient atmosphere by way of a throttle window is present. Upon exceeding the functional path, the throttle sleeve lifts off the actuating piston.

In this negative-pressure booster, one of a negative-pressure valve seat and a negative-pressure valve section has, provided thereto, one or more first protruding sections abutting against the other of the negative-pressure valve seat and negative-pressure valve section, at a site other than a first annular abutment site, in an initial state where an operational force has not been applied to an input member; and/or one of an atmospheric valve seat and an atmospheric valve section has, provided thereto, one or more second protruding sections abutting against the other of the atmospheric valve seat and atmospheric valve section, at a site other than a second annular abutment site, in the initial state where an operational force has not been applied to the input member.