Operationally Reliable Parking Valve

Patent metadata

Field	Value
Publication number	US-2021237707-A1
Application number	US-201917251430-A
Country	US
Kind code	A1
Filing date	Jun 11, 2019
Priority date	Jun 13, 2018
Publication date	Aug 5, 2021
Grant date	—

Abstract

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.

First claim

1 .- 15 . (canceled)

16 . A parking valve for manually actuating a spring-loaded parking brake, comprising:
a housing with a port that is fluidically connectable to a release chamber of a spring-loaded brake cylinder, a port that is fluidically connectable to an air reservoir, and a vent port; a slide configured for manual actuation and being movable along an overall path between two end positions inside the housing, wherein the slide is configured to assume positions along the overall path in which, as a result of at least one seal, there is no fluidic connection between the port to the release chamber and the vent port, and to assume other positions along the overall path in which, as a result of the at least one seal, there is no fluidic connection between the port to the release chamber and the port to the air reservoir; and an inhibiting device, which, during movement at least along a partial path of the overall path, is configured to act on the slide in at least one direction with a continuously variable counterforce dependent on the position of the slide on the partial path.

17 . The parking valve as claimed in claim 16 , wherein at least one of:
the partial path includes at least one end position of the slide, the counterforce is not produced on the basis of mechanical friction between two components, the inhibiting device has a latch, which is configured to hold the slide at least in one position or in a limited region of the overall path, and the at least one seal is provided on the slide or in the housing.

18 . The parking valve as claimed in claim 16 , wherein
the partial path comprises at least two sections of the overall path which do not adjoin one another directly.

19 . The parking valve as claimed in claim 16 , wherein
the counterforce on the slide has a maximum value which is increased by at least 25% relative to a force to which, owing to the design of the slide, said slide is subject during a movement.

20 . The parking valve as claimed in claim 16 , wherein
the counterforce on the slide has a maximum value which is increased by at least 50% relative to the force, which force is owing to the friction of the at least one seal in the housing.

21 . The parking valve as claimed in claim 16 , wherein
the inhibiting device is configured to subject the slide, over a path section of the overall path which does not form part of the partial path, to an assisting force, dependent on the position of the slide on the path section, in the direction of the movement, or to no force.

22 . The parking valve as claimed in claim 21 , wherein
the assisting force is designed to bring about a movement of the slide into the end position which is in the direction of the movement, even without manual actuation.

23 . The parking valve as claimed in claim 21 , wherein
the inhibiting device is designed to ensure that the counterforce and/or the assisting force are/is formed from the minimum to the maximum value thereof over a path whose length is at least 2% of the overall path.

24 . The parking valve as claimed in claim 21 , wherein
the inhibiting device is designed to ensure that the counterforce and/or the assisting force are/is formed from the minimum to the maximum value thereof over a path whose length is at least 8% of the overall path.

25 . The parking valve as claimed in claim 21 , wherein
the inhibiting device is designed to exert the counterforce and/or the assisting force on the slide via magnetic force, the inhibiting device has a magnet and a counterpart, which is designed to be attracted by the magnet, and the counterpart is a second magnet or a magnetic element.

26 . The parking valve as claimed in claim 25 , wherein at least one of:
the magnet is provided on or in the slide and the counterpart is provided on or in the housing, or the magnet is provided on or in the housing and the counterpart is provided on or in the slide, and the magnet and the counterpart are arranged such that the force of attraction thereof becomes a maximum in one end position of the slide, at least relative to all other possible positions of the slide.

27 . The parking valve as claimed in claim 25 , wherein
the inhibiting device has a further magnet or a further counterpart on or in the housing or on or in the slide.

28 . The parking valve as claimed in claim 21 , wherein
the inhibiting device is designed to subject the slide to a counterforce and/or an assisting force which is formed by a vacuum or an excess pressure.

29 . The parking valve as claimed in claim 28 , wherein
the inhibiting device has a chamber which is fluidically closed by the slide and/or a part of the housing, at least when the slide is moved over the partial path, and the chamber is designed to change volume in accordance with the movement of the slide.

30 . The parking valve as claimed in claim 29 , wherein
the closure of the chamber is accomplished by a seal of the slide and/or of the housing.

31 . The parking valve as claimed in claim 30 , wherein
the chamber is formed in the slide and/or the housing.

32 . The parking valve as claimed in claim 29 , wherein
the chamber is formed in the slide and/or the housing.

33 . The parking valve as claimed in claim 29 , wherein
the chamber is designed to be connected to atmosphere or to a venting device when the slide is moved beyond the partial path and/or the path section.

34 . The parking valve as claimed in claim 29 , wherein
the chamber is designed to be connected to an equalization chamber when the slide is moved beyond the partial path and/or the path section.

35 . The parking valve as claimed in claim 29 , wherein
the chamber undergoes a change in volume of at least 5% when the slide is moved over the partial path.

Assignees

• Knorr Bremse Systeme Fuer Nutzfahrzeuge Gmbh

Inventors

• Koncz Laszlo

Classifications

• F16K21/10

  with hydraulic brake cylinder acting on the closure member · CPC title

• B60T15/182

  Trailer brake valves (B60T15/20 and B60T15/246 take precedence) · CPC title

• B60T15/041 Primary

  controlling auxiliary pressure brakes, e.g. parking or emergency brakes (B60T15/048 takes precedence) · CPC title

• B60T13/385

  Control arrangements therefor · CPC title

• B60T13/261

  systems with both indirect application and application by springs or weights and released by compressed air · CPC title