A brake release mechanism for a spring brake actuator includes a brake release bolt having a threaded portion, a running engaging the threaded portion, the running nut being adapted to axially travel along the threaded portion in order to move a spring brake actuator piston against a force of an actuator power spring, an indicator device comprising an indicator pin being at least partially accommodated in a receiving space of the release bolt, wherein the indicator device further comprises a pin actuator for axially moving the pin relative to the receiving space. It is proposed according to the invention that the pin actuator comprises an indicator cap being attached to the pin, the indicator cap comprising a basic body and at least one spacing element being attached to the basic body, the spacing element being configured to abut against the running nut.

Disclosed is a railway braking system including a first pneumatic distribution device formed by a first distributor provided with a single inlet opening connected to a source for supplying pneumatic pressure mediums and with a single outlet opening connected to a parking brake chamber in order to optionally supply a parking brake with a second pneumatic pressure medium so as to place the brake in either of inoperative and operative configurations, and a second pneumatic distribution device formed by a second distributor provided with a single inlet opening connected to the supply source and with a single outlet opening connected to a service pressure chamber in order to supply a service brake with a third pneumatic pressure medium of which the pressure value is predetermined, so as to apply a predetermined braking force when the parking brake is in the operative configuration thereof.

A brake actuator for a railway vehicle brake system has a thrust sleeve configured to provide braking force to the brake system, and a slide axially moveable in the thrust sleeve between a release position and a locking position. The actuator further has a piston biased by spring means and linked to an anchoring member. A plurality of balls are disposed in respective openings of the sleeve between the slide and the anchoring member. In the locking position, the balls are configured to move under the action of a profiled surface of the slide to axially couple the anchoring member with the sleeve. In the release position, the balls are configured to axially uncouple the anchoring member from the sleeve. The profiled slide surface has a locking groove configured to engagingly receive the balls when the slide is in the locking position.

Disclosed is a rail braking system including a detection and storage device designed to receive first information representing the position of a device for locking a service brake piston, to receive second information representing the supply of a service brake pressure chamber with a pneumatic pressure agent, to deduce information representing the application of a parking brake from the first and second information, and to store the deduced information; as a result of which the information representing the application of the parking brake is kept even if the service brake pressure chamber is no longer supplied with the pneumatic pressure agent.

A powered vehicle includes a spring-applied hydraulic release (SAHR) vehicle brake comprising first and second mutually engageable brake elements. The first brake element is secured to or forms part of a rotatable element of the drive train of the vehicle and the second is non-rotatably moveably mounted on the vehicle such that the first and second elements are mutually engageable with and separable from one another. Mutual engagement of the brake elements causes braking of rotation of the rotatable element. The SAHR vehicle brake includes (i) a resiliently deformable member acting on the second brake element so as to urge the first and second brake elements into mutual engagement and (ii) a hydraulic control circuit for applying hydraulic pressure to the second brake element so as to oppose the action of the resiliently deformable member and thereby normally maintain the first and second brake elements separated from one another.

A piston tube assembly (17) for a spring brake actuator (1) includes a first tubular body (35) having a contoured inside surface profile (55) for non-rotationally guiding a running nut (21) of a mechanical release mechanism (19, 21), and an internal breather valve (41) mounted to the piston tube assembly (17) for allowing fluid transport into and out of the piston tube assembly and any volume in fluid communication therewith. The piston tube assembly (17) includes a second tubular body (37) that is of a different material than the first tubular body (35), which encloses the first tubular body (35) and mechanically supports the first tubular body (35), and the internal breather valve (41) is mounted to the first tubular body (35).

A pneumatic brake actuator has a housing and a divider that divides the housing into a spring chamber containing a spring and a pressure chamber. The divider has an opening that receives an end of an actuator tube. A bearing that is positioned within the opening in the divider is joined to both the divider and the actuator tube. A caging bolt has a first end positioned within the actuator tube and extends from the first end through openings in the bearing and housing to a second end positioned outside of the housing. The connection between the bearing, divider and actuator tube contains the spring within the housing in the event that the housing and/or divider fails. The divider can be a piston or a diaphragm and pressure plate. The bearing can be joined to either of the divider and actuator tube with threads and/or by welding.

The invention relates to a railway braking system (1) comprising a first pneumatic distribution device (51) formed by a first distributor provided with a single inlet opening (54a,b) connected to a source for supplying pneumatic pressure mediums (73) and with a single outlet opening (55a,b) connected to a parking brake chamber (25) in order to optionally supply a parking brake (7) with a second pneumatic pressure medium so as to place said brake in either of inoperative and operative configurations, and a second pneumatic distribution device (61) formed by a second distributor provided with a single inlet opening (64a,b) connected to said supply source and with a single outlet opening (65a,b) connected to a service pressure chamber (13) in order to supply a service brake (6) with a third pneumatic pressure medium of which the pressure value is predetermined, so as to apply a predetermined braking force when said parking brake is in the operative configuration thereof.

Disclosed is a rail braking system including a detection and storage device designed to receive first information representing the position of a device for locking a service brake piston, to receive second information representing the supply of a service brake pressure chamber with a pneumatic pressure agent, to deduce information representing the application of a parking brake from the first and second information, and to store the deduced information; as a result of which the information representing the application of the parking brake is kept even if the service brake pressure chamber is no longer supplied with the pneumatic pressure agent.

Disclosed is a brake system for a railroad vehicle, including a parking brake provided with a piston and having a first configuration in which the piston is in a working position in which it acts on a lining support and applies a predetermined force to a brake disc; a second configuration in which the piston is in a rest position in which it does not act on the support and does not apply any force to the disc; and a third configuration in which, when the vehicle is not at a standstill and the ambient temperature in the environment of the disc is greater than a threshold value, it forces the piston to move towards a trip position different from its working and rest positions, in order to limit or cancel the force applied to the disc.