Methods and systems are provided for providing vacuum to a brake booster via an aspirator system. In one example, a system may include an aspirator system fluidly coupled with a brake booster with no intervening components located therebetween.

Methods and systems are provided for providing vacuum to a brake booster via an aspirator system. In one example, a system may include an aspirator system fluidly coupled with a brake booster with no intervening components located therebetween.

An unloader valve apparatus is provided for an air compressor. The unloader valve apparatus comprises a cylindrical piston having a longitudinal central axis and movable along the longitudinal central axis between a loaded position and an unloaded position. The unloader valve apparatus further comprises a stopper member pivotable about a pivot axis between a blocking position in which the stopper member blocks an unloader port when the piston is in the loaded position and an unblocking position in which the stopper member is not blocking the unloader port and is thereby allowing compressed air from the compressor to flow through the unloader port when the piston is in the unloaded position.

An unloader valve apparatus is provided for an air compressor. The unloader valve apparatus comprises a cylindrical piston having a longitudinal central axis and movable along the longitudinal central axis between a loaded position and an unloaded position. The unloader valve apparatus further comprises a stopper member pivotable about a pivot axis between a blocking position in which the stopper member blocks an unloader port when the piston is in the loaded position and an unblocking position in which the stopper member is not blocking the unloader port and is thereby allowing compressed air from the compressor to flow through the unloader port when the piston is in the unloaded position.

A compressed air supply system for a utility vehicle includes an air dryer unit provided with a filter unit, an electrically controllable valve unit and a pneumatically controllable discharge valve unit, a compressor with a coupling, which supplies compressed air to the air dryer unit via a delivery pipe, a multi-circuit safety valve unit which removes the compressed air from the air dryer unit, and an electrically controllable compressor coupling switch valve unit. An electronic control unit controls or regulates the functions of the air dryer unit and the compressor coupling switch valve unit.

A compressed air supply system for a utility vehicle includes an air dryer unit provided with a filter unit, an electrically controllable valve unit and a pneumatically controllable discharge valve unit, a compressor with a coupling, which supplies compressed air to the air dryer unit via a delivery pipe, a multi-circuit safety valve unit which removes the compressed air from the air dryer unit, and an electrically controllable compressor coupling switch valve unit. An electronic control unit controls or regulates the functions of the air dryer unit and the compressor coupling switch valve unit.

A pressure generator for a hydraulic power braking system. The pressure generator is designed to have a ball thread drive and a planetary gear, a spindle nut of the ball thread drive forming a planetary carrier for planetary wheels of the planetary gear. A sun wheel is non-rotatably fixed to a hollow shaft of an electric hollow shaft motor and together with the hollow shaft rotatably supported. The electric hollow shaft motor surrounds the ball thread drive and the planetary gear.

Methods for controlling vacuum within a brake booster by modifying powertrain operation include determining an intake manifold vacuum in response to actuation of a brake pedal. Increasing the intake manifold vacuum if the brake booster vacuum is less than a desired brake booster vacuum. In some embodiments, the transmission is downshifted to increase engine speed and intake manifold vacuum.

A rotating pumping apparatus is provided which may be employed in an automotive brake system. The rotating pumping apparatus includes a sealing member and an oil seal which are disposed around a pump drive shaft, and lubricating grease disposed between the oil seal and the pump drive shaft. The sealing member is made up of a resinous ring and a rubber cup. The sealing member has formed therein a labyrinthine flow path which extends from the resinous ring to the rubber cup. The labyrinthine flow path is designed to permit fluid to flow therethrough and create the resistance to flow of the lubricating grease to avoid leakage of the grease outside the sealing member.

A rotating pumping apparatus is provided which may be employed in an automotive brake system. The rotating pumping apparatus includes a sealing member and an oil seal which are disposed around a pump drive shaft, and lubricating grease disposed between the oil seal and the pump drive shaft. The sealing member is made up of a resinous ring and a rubber cup. The sealing member has formed therein a labyrinthine flow path which extends from the resinous ring to the rubber cup. The labyrinthine flow path is designed to permit fluid to flow therethrough and create the resistance to flow of the lubricating grease to avoid leakage of the grease outside the sealing member.