Methods and systems are provided for controlling an aspirator shut-off valve in a boosted engine. One example method includes increasing an opening of the aspirator shut-off valve to allow motive flow through an aspirator in response to engine speed between a first, lower speed and a second, higher speed. As such, control of the aspirator shut-off valve may be simplified.

Methods and systems are provided for controlling an aspirator shut-off valve in a boosted engine. One example method includes increasing an opening of the aspirator shut-off valve to allow motive flow through an aspirator in response to engine speed between a first, lower speed and a second, higher speed. As such, control of the aspirator shut-off valve may be simplified.

The present invention relates to a vehicle braking arrangement for a vehicle with wheels contacting the ground during normal running. The vehicle braking arrangement includes an emergency brake control unit, a first emergency braking system including non-reversible braking means arranged to operate independently of the vehicle wheels, at least one acceleration detector, and a wheel brake anti-locking system. The emergency brake control unit is arranged to input acceleration data (a) when the wheel brake anti-locking system is active, and to calculate the coefficient of friction () between the wheels and the ground. The emergency brake control unit is arranged to determine if the first emergency braking system should be activated in dependence of a first plurality of parameters, where one of these parameters is the coefficient of friction ().

The present invention relates to a vehicle braking arrangement for a vehicle with wheels contacting the ground during normal running. The vehicle braking arrangement includes an emergency brake control unit, a first emergency braking system including non-reversible braking means arranged to operate independently of the vehicle wheels, at least one acceleration detector, and a wheel brake anti-locking system. The emergency brake control unit is arranged to input acceleration data (a) when the wheel brake anti-locking system is active, and to calculate the coefficient of friction () between the wheels and the ground. The emergency brake control unit is arranged to determine if the first emergency braking system should be activated in dependence of a first plurality of parameters, where one of these parameters is the coefficient of friction ().

An arrangement of an electric vacuum pump, for example, in a vehicle, wherein a mounting element is provided on which the vacuum pump is installed, and wherein the vacuum pump comprises a pump chamber part and a motor part, and wherein a longitudinal axis extends through the pump chamber part and the motor part. According to the invention, the vacuum pump has a horizontal arrangement with respect to a gravitational direction, wherein the installation of the vacuum pump on the mounting element is limited to two mounting points, and wherein a center of gravity of the vacuum pump lies on a connection axis between the two mounting points.

An arrangement of an electric vacuum pump, for example, in a vehicle, wherein a mounting element is provided on which the vacuum pump is installed, and wherein the vacuum pump comprises a pump chamber part and a motor part, and wherein a longitudinal axis extends through the pump chamber part and the motor part. According to the invention, the vacuum pump has a horizontal arrangement with respect to a gravitational direction, wherein the installation of the vacuum pump on the mounting element is limited to two mounting points, and wherein a center of gravity of the vacuum pump lies on a connection axis between the two mounting points.

An expansion chamber for a rotary vane vacuum pump is provided. The expansion chamber is in fluid communication with the discharge side of the rotary vane vacuum pump, such that the expansion chamber attenuates sound as a Helmholtz resonator. The expansion chamber includes an internal volume of between 80 cubic centimeters and 100 cubic centimeters, inclusive, and includes a curved sidewall that extends partially around, and generally conforms to, the exterior of the rotary vane vacuum pump. The expansion chamber also includes a downward extending port, open to the atmosphere, for attachment to a hose in applications in which the expansion chamber is below a water line.

Methods and systems are provided for ventilating a crankcase in a boosted engine. An example method may include selectively enabling one of crankcase ventilation and aspirator motive flow via an electrically controlled valve, the aspirator motive flow being enabled in response to a demand for vacuum from a vacuum consumer. In this way, the crankcase of the boosted engine may be ventilated until the vacuum consumer demands vacuum.

Methods and systems are provided for ventilating a crankcase in a boosted engine. An example method may include selectively enabling one of crankcase ventilation and aspirator motive flow via an electrically controlled valve, the aspirator motive flow being enabled in response to a demand for vacuum from a vacuum consumer. In this way, the crankcase of the boosted engine may be ventilated until the vacuum consumer demands vacuum.

A vacuum system for the brake booster of a motor vehicle includes a demand-driven vacuum pump and a vacuum line connected on one end to the vacuum chamber of the brake booster and connected on another end to an intake port of the demand-driven vacuum pump. The vacuum system may include a discharge device arranged on an exhaust air opening of the vacuum system for ensuring bidirectional air volume flow between the external surroundings of the discharge device and the exhaust air opening of the vacuum system, which preventing liquids from reaching the exhaust air opening of the vacuum system as an air volume flows from the exterior surroundings into the exhaust air opening of the vacuum system. The vacuum system may also include a check valve arranged between the intake port of the demand-driven vacuum pump and the connection to a vacuum chamber of the brake booster.