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CN-115720554-B - Method for checking a height selection valve

CN115720554BCN 115720554 BCN115720554 BCN 115720554BCN-115720554-B

Abstract

The invention relates to a method for checking a shuttle valve (2) in a pneumatic system (100), wherein the shuttle valve (2) has a first shuttle valve connection (2.1), a second shuttle valve connection (2.2) and a third shuttle valve connection (2.3), wherein the higher of the pressures (p 1, p 2) applied to the first shuttle valve connection (2.1) and the second shuttle valve connection (2.2) is always regulated to the third shuttle valve connection (2.3), wherein the method comprises the steps of a) regulating the first pressure (p 1) to the first shuttle valve connection (2.1), b) ascertaining an indicator value (G1, G1T) for the first pressure (p 1) at the first shuttle valve connection (2.1), and c) comparing the indicator value (G1, G1T) for the first pressure (p 1) with a predetermined first comparison value (GV 1, 1) provided for this purpose and ascertaining if the deviation is greater than a first tolerance (T) and/or ascertaining a fault (E2) of the shuttle valve.

Inventors

  • Julian Vantile

Assignees

  • 采埃孚商用车系统全球有限公司

Dates

Publication Date
20260505
Application Date
20210629
Priority Date
20200701

Claims (20)

  1. 1. Method for checking a shuttle valve (2) in a pneumatic system (100), wherein the shuttle valve (2) has a first shuttle valve connection (2.1), a second shuttle valve connection (2.2) and a third shuttle valve connection (2.3), wherein the higher of the pressures (p 1, p 2) applied at the first shuttle valve connection (2.1) and the second shuttle valve connection (2.2) is always regulated to the third shuttle valve connection (2.3), wherein the method comprises the following steps: a) Regulating a first pressure (p 1) to the first shuttle valve interface (2.1); b) Knowing an indication value (G1, G1T) for the first pressure (p 1) at the first shuttle valve interface (2.1); c) Comparing the indication value (G1, G1T) for the first pressure with a predetermined first comparison value (GV 1, GS 1) provided for this purpose and, if the deviation is greater than a first tolerance (T1), detecting and/or outputting a fault (E) of the shuttle valve (2); d) Regulating a second pressure (p 2) to the second shuttle valve interface (2.1); e) Knowing an indication value (G2, G2T) for the second pressure (p 2) at the second shuttle valve connection (2.2), and F) The indication value (G2, G2T) for the second pressure is compared with a second predetermined comparison value (GV 2, GS 2) provided for this purpose and, if the deviation is greater than a second tolerance (T2), a fault (E) of the shuttle valve (2) is detected and/or output.
  2. 2. The method according to claim 1, comprising the steps of: g) -comparing the difference between the indication value (G1) for the first pressure (p 1) and the indication value (G2) for the second pressure with a predetermined first threshold value, and-if the difference is below the first threshold value, -learning and/or outputting a fault (E) of the shuttle valve (2).
  3. 3. The method according to claim 1, wherein in step d) a second pressure (p 2) is regulated for the second shuttle valve interface (2.2) during the time when the first pressure (p 1) has been regulated for the first shuttle valve interface (2.1).
  4. 4. A method according to any one of claims 1 to 3, wherein the indication value for the first pressure (p 1) is a pressure gradient (G1) and the predetermined first comparison value (GV 1) is a first comparison pressure gradient (GV 1).
  5. 5. A method according to any one of claims 1 to 3, wherein the indication value for the first pressure (p 1) is a pressure gradient profile (G1T) and the predetermined first comparison value is a nominal profile (GS 1).
  6. 6. A method according to any one of claims 1 to 3, comprising the steps of: -regulating the second shuttle valve interface (2.2) with a third pressure (p 3) that is less than the maximum pressure (pMAX); -regulating a fourth pressure (p 4) to the first shuttle valve interface (2.1), wherein the fourth pressure (p 4) is higher than the third pressure (p 3); -knowing the pressure gradient profile (G4T) with respect to time (T) at the first shuttle valve interface (2.1); -ascertaining a deviation of the ascertained pressure gradient profile (G4T) from a predetermined setpoint profile (GS 4), and-ascertaining and/or outputting a fault (E) of the shuttle valve (2) if a deviation is ascertained.
  7. 7. A method according to any one of claims 1 to 3, comprising the steps of: -regulating a fifth pressure (p 5) to the first shuttle valve interface (2.1); -regulating a sixth pressure (p 6) to the second shuttle valve interface (2.2) during regulating the fifth pressure (p 5), wherein the sixth pressure (p 6) is a very small pressure; -detecting the pressure (p 6.2) applied at the second shuttle valve interface (2.2) over a period of time and-upon an increase of the pressure (p 6.2) applied at the second shuttle valve interface (2.2), learning and/or outputting a failure (E) of the shuttle valve (2).
  8. 8. The method according to claim 7, comprising the steps of: -deflating the first shuttle valve interface (2.1) from a fifth pressure (p 5) to an ambient pressure (p 0) and regulating a sixth pressure (p 6) to the second shuttle valve interface (2.2); -detecting the pressure (p 6.2) applied at the second shuttle valve interface (2.2) over a period of time, and-learning and/or outputting a failure (E) of the shuttle valve (2) when the pressure (p 6.2) applied at the second shuttle valve interface (2.2) remains within a predetermined tolerance range.
  9. 9. A method according to any one of claims 1 to 3, comprising the steps of: -knowing the current reservoir pressure (pVT), wherein step c) is performed at least taking into account the known current reservoir pressure (pVT).
  10. 10. A method according to any one of claims 1 to 3, wherein at least the predetermined first comparison value is a learned value based on previously measured values.
  11. 11. A method according to any one of claims 1 to 3, comprising the steps of: -invoking at least said predetermined first comparison value (GV 1, GV2, GV 4) from an internal storage medium (M) and/or wirelessly from a cloud service (C).
  12. 12. A method according to any one of claims 1 to 3, wherein a first valve module (4) is coupled with the first shuttle valve interface (2.1) and a second valve module (6) is coupled with the second shuttle valve interface (2.2), wherein the first and second valve modules (4, 6) are in indirect or direct electronic communication with each other, and wherein the third shuttle valve interface (2.3) is connected with a consumer.
  13. 13. The method according to claim 12, wherein the steps are carried out during braking of the vehicle (200), and wherein the first pressure (p 1) is a first braking pressure (pB 1, pBVA, pBHA) for braking the vehicle (200).
  14. 14. The method of claim 12, wherein the steps are performed while the vehicle is stationary, wherein the method further comprises the steps of: -receiving a departure control signal to implement departure control, and in response to receiving said departure control signal, implementing at least steps a) to c).
  15. 15. The method of claim 1, wherein the pneumatic system (100) is an electronically controllable pneumatic braking system (102).
  16. 16. The method according to claim 12, wherein the first valve module (4) is configured as a first axle modulator (10).
  17. 17. The method according to claim 12, wherein the second valve module (6) is configured as a second bridge modulator (12).
  18. 18. The method according to claim 12, wherein the consumer is configured as a brake actuator (8).
  19. 19. Pneumatic system (100) for a vehicle (200), comprising A shuttle valve (2) having a first shuttle valve port (2.1), a second shuttle valve port (2.2) and a third shuttle valve port (2.3), wherein the higher of the pressures (p 1, p 2) applied at the first shuttle valve port (2.1) and the second shuttle valve port (2.2) is always regulated to the third shuttle valve port (2.3); -a first valve module (4) connected to the first shuttle valve interface (2.1) for regulating the first shuttle valve interface to a first pressure (p 1), and having a first pressure sensor (14) for detecting an indication value for the first pressure (p 1); A second valve module (6) which is connected to the second shuttle valve connection (2.2) in order to regulate the second shuttle valve connection to a second pressure (p 2), and which has a second pressure sensor (16) for detecting an indication of the second pressure (p 2), and -An electronic control unit (ECU 1, ECU 2) connected with the first and second valve modules (4, 6) for receiving first and second pressure signals (SP 1, SP 2) of the first and second pressure sensors (14, 16), wherein the electronic control unit (ECU 1, ECU 2) further has means adapted to implement the steps of the method according to any one of claims 1 to 18.
  20. 20. The pneumatic system (100) according to claim 19, wherein the first valve module (4) is configured as a first axle modulator (10) and the second valve module (6) is configured as a second axle modulator (12), and wherein the third shuttle valve interface (2.3) is fluidly connected with a brake actuator (8).

Description

Method for checking a height selection valve Technical Field The invention relates to a method for checking a shuttle valve in a pneumatic system, preferably in an electronically controllable pneumatic braking system, wherein the shuttle valve has a first shuttle valve connection, a second shuttle valve connection and a third shuttle valve connection, wherein the higher of the pressures applied to the first and second shuttle valve connections is always regulated to the third shuttle valve connection. The invention also relates to a pneumatic system for a vehicle, preferably a commercial vehicle, having such a shuttle valve, and to a vehicle, preferably a commercial vehicle, having a pneumatic system of the aforementioned type. Background The shuttle valve that diverts the higher of the pressures applied at the first and second ports to the third port is also referred to as the "pick-up valve". Such shuttle valves are used in a wide variety of braking systems, for example, in order to couple redundant systems, divert redundant pressures, or take over other control tasks. In the context of redundant systems, the shuttle valve can also be used in particular with a high degree of automation, in particular at SAE 2 to 5, in particular at 3 to 5. It is important here that measures and methods are provided for checking such shuttle valves, since in vehicles with a high degree of automation, the human driver can no longer recognize faults without restriction. It is in principle possible to check such a shuttle valve using additional, special sensors, which check the functional effect of the shuttle valve. However, this is costly, increases the installation space and costs, and is hardly economically usable in a wide range of fields. This occurs especially when considering that a plurality of such shuttle valves are typically used in a braking system. Disclosure of Invention The object of the present invention is therefore to specify a method for checking such a shuttle valve, by means of which the shuttle valve can be checked simply, inexpensively and safely even during the operation of the vehicle. In a first aspect, the invention solves the object by a method of the type mentioned at the outset, having the steps of a) regulating a first pressure to a first shuttle valve connection, b) detecting an indication of the first pressure at the first shuttle valve connection, and c) comparing the indication of the first pressure with a predetermined first comparison value provided for this purpose, and if the deviation is greater than a first tolerance, detecting and/or outputting that the shuttle valve is defective. The invention is based on the idea that a fault-free operation of the height selection valve is ensured by comparing the indication values for the pressure applied at the first shuttle valve interface during inflation and deflation. That is to say, during the regulation of the first pressure to the first shuttle valve interface, an indication value for the pressure is ascertained and then compared with a corresponding comparison value in order to check the functional effect of the shuttle valve. This can occur both through extended test activation, for example in the context of extended departure control (Abfahrkontrolle), and also during continuous operation or during active pressure regulation. When the first pressure is regulated in step a) for the first shuttle valve connection, the second shuttle valve connection is preferably not pressurized, but preferably deflated. There are also embodiments which will be described later, in which parallel pressure regulation is performed. When the first shuttle valve port is regulated to a first pressure and the second shuttle valve port is pressurized to ambient pressure, the shuttle valve should react such that the first pressure is provided at the third shuttle valve port. Faults that may typically occur in a shuttle valve are, on the one hand, leaks, which occur, for example, when a valve ball jams, or incorrect positioning of a valve element, etc. A leak may exist between the first and third shuttle valve interfaces, between the second and third shuttle valve interfaces, or between the first and second shuttle valve interfaces as well. All these faults should be identified by the method. In principle, it is possible and preferred to regulate the first, second and further pressures for the first and second shuttle valve connections, which are inflated from the ambient pressure, inflated from the further pressure or deflated from the higher pressure in order to reach the first or second or further pressure. For example, it may occur that the maximum pressure is regulated during operation and then the maximum pressure is let out to the first, second or further pressure in order to regulate the corresponding first, second or further pressure. A corresponding pressure can also be provided at the first or second shuttle valve interface in this manner. The indication