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.

An example valve includes: (i) a valve body defining a first longitudinal bore therein and including a first inlet, a second inlet, and an outlet; (ii) a cage disposed in the first longitudinal bore coaxial with the valve body, where the cage defines a second longitudinal bore therein; (iii) a pin mounted and extending longitudinally within the second longitudinal bore at an end of the cage adjacent to the first inlet; and (iv) a spool shiftably mounted within the second longitudinal bore and configured to move axially therein to shift between a first position and a second position. The spool includes a blind hole formed at an end thereof facing the pin and coaxial therewith, such that as the spool shifts from the second position to the first position, a portion of the pin is received within the blind hole of the spool.

The embodiments disclosed herein provide a check valve aspirator including a venturi pipe having a converging section with a converging inlet and a converging outlet, and a diverging section with a diverging inlet and a diverging outlet. The converging outlet is in fluid communication with the diverging inlet. An outlet channel is in fluid communication with the venturi pipe and has an outlet port.

A normally closed port valve seals a hydraulic hose connection port of a hydraulic bicycle component. Connection of an end of a hydraulic hose assembly to the port opens the valve, placing the assembly's hydraulic fluid chamber in fluid communication with the interior of the hose assembly. A hydraulic cylinder of the assembly is in fluid communication with the chamber. A spring may be used to bias the valve to a closed condition and simultaneously to bias a brake actuating piston to a non-actuated position.

A pneumatic brake system (110) for a commercial vehicle (1) has one spring brake (27), a protection valve (56), a parking brake unit (30), a network of pipelines (40), at least a first (4) and a second (5) tank with compressed air and a relay valve (19) for the parking brake unit (30). A first subnetwork of pipelines (40a) comprises pipelines configured to be pressurized at all times. A second subnetwork of pipelines (40b) comprises at least one pipeline configured to be non-pressurized when the parking brake function is applied. The first subnetwork (40a) comprises pipelines establishing fluid communication between the tanks (4, 5) and the parking brake unit (30), wherein the direction of air flow in these pipelines is by at least one thereto associated valve (50). A method for managing an air flow to an air-actuated spring brake (27) of a pneumatic brake system (110) is disclosed.

A pneumatic brake system (110) for a commercial vehicle (1) has one spring brake (27), a protection valve (56), a parking brake unit (30), a network of pipelines (40), at least a first (4) and a second (5) tank with compressed air and a relay valve (19) for the parking brake unit (30). A first subnetwork of pipelines (40a) comprises pipelines configured to be pressurized at all times. A second subnetwork of pipelines (40b) comprises at least one pipeline configured to be non-pressurized when the parking brake function is applied. The first subnetwork (40a) comprises pipelines establishing fluid communication between the tanks (4, 5) and the parking brake unit (30), wherein the direction of air flow in these pipelines is by at least one thereto associated valve (50). A method for managing an air flow to an air-actuated spring brake (27) of a pneumatic brake system (110) is disclosed.

A pressure variation damper for a slip-regulated, hydraulic vehicle brake system includes a damper housing and a tubular damper element. The damper element is disposed in the damper housing and configured for elastic deformation. The damper element is subjected on an inside and/or on an outside to a fluid. Possible pressure variations of the fluid are to be damped. The damper element comprises a corrugation on the outside and a corrugation on the inside configured to reduce a change in a wall thickness of the damper element owing to the corrugation on the outside.

A pressure variation damper for a slip-regulated, hydraulic vehicle brake system includes a damper housing and a tubular damper element. The damper element is disposed in the damper housing and configured for elastic deformation. The damper element is subjected on an inside and/or on an outside to a fluid. Possible pressure variations of the fluid are to be damped. The damper element comprises a corrugation on the outside and a corrugation on the inside configured to reduce a change in a wall thickness of the damper element owing to the corrugation on the outside.

Compressed air supplied into a housing is expanded for reducing air humidity in the housing in response to the expansion of the compressed air. As a result, it is possible in a simple manner for a component to be operated in a dry environment. The component can be dried and condensation on the component can be prevented.