An arrangement of motor vehicle units includes a vacuum pump, a power brake unit, a pump which pumps a hydraulic fluid with a control pressure, and a control valve. The vacuum pump comprises a pump rotor, a coupling element, a control connection, a coupling arrangement switchable by the control connection to lock/unlock the coupling element with the pump rotor, and a suction connection. The power brake unit comprises a negative pressure chamber connected with the suction connection. The control valve, when unlocked, switches the control pressure of the hydraulic fluid through to the control connection to unlock. The control valve comprises an actuator acted on by a pressure of the negative pressure chamber which switches the control pressure through to the control connection if the pressure in the negative pressure chamber is greater than a threshold pressure so that the switchable control valve is switched into its unlocked state.

Venturi devices are disclosed that have a housing defining a conduit having a Venturi gap. Downstream of and bypassing the Venturi gap is a bypass check valve that defines an internal cavity having a first seat, a second seat, an inlet port, at least two outlet ports, and a seal member seated therein that is translatable between a closed position against the first seat and an open position against the second seat. The two outlet ports of the bypass check valve enter the conduit at opposing positions disposed a distance from a top of the conduit, which is located at a midsagittal plane of the housing. Further, a transition from a tapering section downstream of the Venturi gap and upstream of each of the two outlet ports to a discharge section downstream of the two outlet ports forms a gradually, continuously tapering interior surface of the conduit.

A simple, compact, and economical motor/pump unit for supplying vacuum to a pneumatic brake booster of a motor-vehicle brake system, wherein the motor/pump unit is designed as a diaphragm pump having a single elastomeric diaphragm, which is moved by an electrically operated motor unit by an eccentric drive, and has a pump housing and a working-space cover and the diaphragm is clamped between the pump housing and the working-space cover at the radial outer edge of the diaphragm in a sealing manner and the working-space cover is designed as a multi-part working-space cover having an upper cover, a lower cover, and an inlet valve and an outlet valve, which are arranged between the upper cover and the lower cover and control the air circulation through the working space.

A simple, compact, and economical motor/pump unit for supplying vacuum to a pneumatic brake booster of a motor-vehicle brake system, wherein the motor/pump unit is designed as a diaphragm pump having a single elastomeric diaphragm, which is moved by an electrically operated motor unit by an eccentric drive, and has a pump housing and a working-space cover and the diaphragm is clamped between the pump housing and the working-space cover at the radial outer edge of the diaphragm in a sealing manner and the working-space cover is designed as a multi-part working-space cover having an upper cover, a lower cover, and an inlet valve and an outlet valve, which are arranged between the upper cover and the lower cover and control the air circulation through the working space.

Methods and systems are provided for expediting catalyst warm-up. In one example, a method may include flowing exhaust gas from an engine first through an emission control device and then through a turbine to rotate the turbine in a reverse direction, the rotation of the turbine in the reverse direction generating intake manifold vacuum for a vacuum consumer via a compressor coupled to the turbine. In this way, heat loss through a turbine may be avoided.

A brake device may include: a master cylinder including a master piston moved in connection with a pedal, and a master cylinder body having the master piston movably inserted therein and containing fluid of which hydraulic pressure is varied when the master piston is moved; a pedal force generation part housed in the master cylinder body, and restricting a motion of the master piston while interfering with the master piston depending on the motion of the master piston; a braking actuator configured to generate hydraulic pressure; an actuator connection part connecting the braking actuator to a brake mounted on a wheel; and a master connection part connecting the master cylinder to the actuator connection part.

A brake device may include: a master cylinder including a master piston moved in connection with a pedal, and a master cylinder body having the master piston movably inserted therein and containing fluid of which hydraulic pressure is varied when the master piston is moved; a pedal force generation part housed in the master cylinder body, and restricting a motion of the master piston while interfering with the master piston depending on the motion of the master piston; a braking actuator configured to generate hydraulic pressure; an actuator connection part connecting the braking actuator to a brake mounted on a wheel; and a master connection part connecting the master cylinder to the actuator connection part.

In order to provide a hydraulic actuating system for actuating a parking lock of a motor vehicle, which hydraulic actuating system manages with as few components as possible which are simple, robust, relatively insusceptible to faults and inexpensive, with a simultaneously low installation space requirement, and the hydraulic layout of which hydraulic actuating system makes a simple actuation and a simple movement possible for locking and unlocking the parking lock, it is provided that a pumping device which can operate bidirectionally with a locking delivery direction and with a releasing delivery direction is used as pumping device, and check valves are arranged in the hydraulic circuit in such a way that, by way of actuation of the pumping device in the locking delivery direction, the parking lock moves into the locked position and, upon actuation of the pumping device in the releasing delivery direction, the parking lock moves into the released position.

In order to provide a hydraulic actuating system for actuating a parking lock of a motor vehicle, which hydraulic actuating system manages with as few components as possible which are simple, robust, relatively insusceptible to faults and inexpensive, with a simultaneously low installation space requirement, and the hydraulic layout of which hydraulic actuating system makes a simple actuation and a simple movement possible for locking and unlocking the parking lock, it is provided that a pumping device which can operate bidirectionally with a locking delivery direction and with a releasing delivery direction is used as pumping device, and check valves are arranged in the hydraulic circuit in such a way that, by way of actuation of the pumping device in the locking delivery direction, the parking lock moves into the locked position and, upon actuation of the pumping device in the releasing delivery direction, the parking lock moves into the released position.

A system and method for conserving vacuum within a vehicle is described. In one example, vacuum is conserved via limiting volume expansion of a brake booster working chamber.