A parking valve for manually actuating a spring-loaded parking brake, includes: a housing with a port that can be fluidically connected to a release chamber of a spring-loaded brake cylinder, a port that can be fluidically connected to a brake supply reservoir, and a ventilation port; a slide for manual actuation and which can be moved along a full section between two end positions inside the housing. The slide assumes positions along the full section, in which, as a result of at least one seal, there is no fluidic connection between the port to the release chamber and the ventilation port, and assumes other positions along the full section, in which, as a result of the at least one seal, there is no fluidic connection between the port of the release chamber and the port to the brake supply reservoir. A blocking device acts on the slide during movement at least along a partial section of the full section in at least one direction, with a continuously variable counterforce dependent on the position of the slide on the partial section.

A method operates a braking device for motor vehicles, in particular for utility vehicles. Along a trailer supply line for supplying air to a parking brake of a trailer and/or a trailer control line for supplying air to an operating brake of a trailer, the air pressure is measured by at least one pressure transducer and is transmitted in the form of an electric signal to an electronic control unit of the motor vehicle. In the event of a faulty pressure change response, an open trailer supply line and/or an open trailer control line is detected.

A utility vehicle control device for a parking brake device of a trailer vehicle includes a pneumatic supply connection, a control connection for controlling a spring brake cylinder, a directly manually actuatable parking valve, a first connection line and a control valve for controlling the parking valve. The parking valve is arranged in the first connection line, and wherein as a result of the parking valve, the supply connection and the control connection can be connected via the first connection line. A control line branches from the first connection line. The control line is connected to a first pneumatic control input of the control valve, wherein the control valve has a second pneumatic control input. In the event of an unexpected reduction in operating pressure in the first connection line and/or in the control line, the control valve can be controlled by the first or second control input of the control valve such that a switching state of the parking valve can be pneumatically controlled by the control valve independently of an operating state of the supply connection, whereby the control connection is ventilated by the parking valve.

Please substitute the new Abstract submitted herewith for the original Abstract: An electropneumatic parking brake control device controls a parking brake including at least one spring brake actuator. The control device includes a relay valve with a control chamber and a vent. The control chamber can be connected to the vent via at least one second throttle element and/or at least one third throttle element depending on the position of the relay piston.

A brake actuator assembly including a pressure plate presenting an opening, a push rod that is coupled to the pressure plate, a diaphragm that is coupled to the pressure plate, and a retainer that engages the push rod. The push rod has an outer surface and at least one protrusion extending outward from the outer surface. The retainer engages the protrusion such that at least a portion of the diaphragm is positioned between the pressure plate and the retainer.

A brake actuator assembly including a pressure plate presenting an opening, a push rod that is coupled to the pressure plate, a diaphragm that is coupled to the pressure plate, and a retainer that engages the push rod. The push rod has an outer surface and at least one protrusion extending outward from the outer surface. The retainer engages the protrusion such that at least a portion of the diaphragm is positioned between the pressure plate and the retainer.

A control valve for applying a spring-loaded brake pressure to spring-loaded parts of a rear-axle wheel brake is pneumatically activated as a function of a parking-brake braking demand and a service-brake braking demand. A first control chamber is connected via a first control piston to a control arrangement in the control valve. During an adjustment of the first control chamber via the service-brake control pressure, the spring-loaded brake pressure at the working output is a function of the service-brake control pressure or of the parking-brake control pressure. The first control piston is connected to a third control chamber, wherein the pressure in the first control chamber acts on the first control piston in one direction, and the pressure in the third control chamber acts on the first control piston in the opposite direction. The first control chamber is selectively connectable to the third control chamber via a switchable bypass valve.

A brake actuator has a plurality of actuator housing portions, a parking piston axially displaceable within one of the actuator housing portions, and a service piston axially displaceable independently of the parking piston within another of the actuator housing portions. A brake actuator rod projecting from the other of the actuator housing portions moves outward of that actuator housing portion upon at least one of fluid supply to a first substantially torus-shaped service brake bladder and fluid relief from a second substantially torus-shaped parking brake bladder. The brake actuator rod can be moved inward into the other of the actuator housing portions upon fluid relief from the first substantially torus-shaped service brake bladder, and fluid supply to the second substantially torus-shaped parking brake bladder or both.

A brake actuator has a plurality of actuator housing portions, a parking piston axially displaceable within one of the actuator housing portions, and a service piston axially displaceable independently of the parking piston within another of the actuator housing portions. A brake actuator rod projecting from the other of the actuator housing portions moves outward of that actuator housing portion upon at least one of fluid supply to a first substantially torus-shaped service brake bladder and fluid relief from a second substantially torus-shaped parking brake bladder. The brake actuator rod can be moved inward into the other of the actuator housing portions upon fluid relief from the first substantially torus-shaped service brake bladder, and fluid supply to the second substantially torus-shaped parking brake bladder or both.

Disclosed is a brake system for a railway vehicle, including linings each having at least one positioning member for mechanically fastening the linings in a predetermined position on the system with respect to a disc of the vehicle and a bearing face for tightly gripping the disc under the action of an actuator of the system, and at least one return member for separating the linings from the disc in order to release it when the linings are freed from the action of the actuator; each lining has at least one fastening member formed on an edge, the return member has two opposite end lugs connected to one another by an elastic portion and each mechanically fastened with a the fastening member, and the system is configured such that the fastening members and the end lugs are situated at a distance from the at least one positioning member.