Vehicle braking system

Patent metadata

Field	Value
Publication number	US-11685352-B2
Application number	US-201716315845-A
Country	US
Kind code	B2
Filing date	Jul 4, 2017
Priority date	Jul 5, 2016
Publication date	Jun 27, 2023
Grant date	Jun 27, 2023

Abstract

A vehicle braking system comprising a spring brake actuator having a spring brake chamber, a spring brake control assembly and an immobiliser valve which is movable between brake release position in which the spring brake control assembly is operable to cause the flow of pressurised fluid into the spring brake chamber or to vent the spring brake chamber to a low pressure region, and an immobilise position in which the spring brake control assembly is operable to connect the spring brake chamber to a low pressure region but cannot be operated to cause the flow of pressurised fluid into the spring brake chamber.

First claim

The invention claimed is:

1. A vehicle braking system, comprising:
a spring brake actuator having a spring brake chamber for controlling application of a spring brake;
a spring brake control assembly; and
an immobiliser valve which is movable between a brake release position and an immobilise position,
the brake release position configuring the spring brake control assembly so that it is operable to move between a first state in which flow of pressurised fluid is permitted into the spring brake chamber and a second state in which the spring brake chamber is vented, and
the immobilise position configuring the spring brake control assembly so that it is operable to move to the second state and to prevent the first state such that the immobiliser valve is activated to its immobilise position prior to, and independently from, application of the spring brake.

2. The vehicle braking system according to claim 1 wherein the immobiliser valve has an inlet, an outlet, and a check valve and is configured such that when the immobiliser valve is in its brake release position, the inlet is connected directly to the outlet so that flow of fluid between the inlet and the outlet is permitted, and when the immobiliser valve is in the immobilise position, the inlet is connected to the outlet via the check valve such that flow of fluid from the outlet to the inlet is permitted and the flow of fluid from the inlet to the outlet is prevented.

3. The vehicle braking system according to claim 1 , wherein the spring brake control assembly includes a spring brake control valve having an inlet for pressurised fluid, an outlet which is connected to the spring brake chamber via a spring brake line, and an exhaust port which is connected to a low pressure region, the spring brake control valve being movable between a first position, in which the inlet of the spring brake control valve is connected to the outlet whilst the exhaust port is closed, and a second position, in which the outlet of the spring brake control valve is connected to the exhaust port whilst the inlet is closed.

4. The vehicle braking system according to claim 3 wherein the immobiliser valve is located in the spring brake line and arranged such that when the immobiliser valve is in the immobilise position, the immobiliser valve permits flow of fluid from the spring brake chamber to the outlet of the spring brake control valve whilst substantially preventing flow of fluid from the outlet of the spring brake control valve into the spring brake chamber.

5. The vehicle braking system according to claim 3 , wherein the spring brake control valve has at least one of a supply of pressurised fluid to a control port causing the spring brake control valve to move to its first position or a resilient biasing element which acts to urge the spring brake control valve into the second position.

6. The vehicle braking system according to claim 5 wherein the spring brake control valve is configured such that when the fluid pressure at the control port exceeds a pre-determined level, the spring brake control valve moves against the biasing force of the resilient biasing element from the second position to the first position.

7. The vehicle braking system according to claim 6 wherein an electrically operable emergency braking override valve is located in a park line and has a first inlet which is connected to a portion of the park line facilitating the supply of pressurised fluid, a second inlet which is connected to a pressurised fluid reservoir, and an outlet which is connected to a portion of the park line which extends towards the control port of the spring brake control valve, the emergency braking override valve being movable between a first position, in which its first inlet is connected to the outlet, and a second position in which the second inlet is connected to the outlet.

8. The vehicle braking system according to claim 7 wherein the immobiliser valve is located in the park line between the outlet of the emergency braking override valve and the control port of the spring brake control valve.

9. The vehicle braking system according to claim 7 wherein the emergency braking override valve is located in the park line between the immobiliser valve and the control port of the spring brake control valve.

10. The vehicle braking system according to claim 5 , wherein the immobiliser valve is located in a park line facilitating the supply of pressurised fluid to the control port of the spring brake control valve, the immobiliser valve, when in its brake release position, allowing flow of fluid in a first direction along the park line away from the control port and along the park line in a second direction towards the control port, and when in the immobilise position allowing the flow of fluid in the first direction along the park line and substantially preventing the flow of fluid in the second direction along the park line.

11. The vehicle braking system according to claim 10 , wherein an electrically operable emergency braking override valve is located in the park line and has a first inlet which is connected to a portion of the park line facilitating the supply of pressurised fluid, a second inlet which is connected to a pressurised fluid reservoir, and an outlet which is connected to a portion of the park line which extends towards the control port of the spring brake control valve, the electrically operable emergency braking override valve being movable between a first position, in which its first inlet is connected to the outlet, and a second position, in which the second inlet is connected to the outlet.

12. The vehicle braking system according to claim 11 , wherein the immobiliser valve is located in the park line between the outlet of the electrically operable emergency braking override valve and the control port of the spring brake control valve.

13. The vehicle braking system according to claim 11 , wherein the electrically operable emergency braking override valve is located in the park line between the immobiliser valve and the control port of the spring brake control valve.

14. The vehicle braking system according to claim 10 , wherein a park valve is located in the park line and is movable between a first position, in which the park valve does not impede flow of fluid along the park line, and a second position, in which the park valve vents the portion of the park line extending towards the control port of the spring brake control valve.

15. The vehicle braking system according to claim 14 , wherein an emergency braking override valve is located in the park line between the control port of the spring brake control valve and the park valve.

16. The vehicle braking system according to claim 14 , wherein the immobiliser valve is located in the park line between the park valve and the emergency braking override valve.

17. The vehicle braking system according to claim 10 , wherein the spring brake control valve comprises a control port connected to a connector via the park line.

18. The vehicle braking system according to claim 1 , wherein the vehicle braking system further includes an electrically operable emergency braking override valve which is electrically operable to cause the flow of pressurised fluid to the spring brake chamber even when the immobiliser is in the immobilise position.

19. The vehicle braking system according to claim 1 , wherein the immobiliser valve is an electrically operated bi-stable valve, which, when in the brake release position and on receipt of a first electrical signal, moves to th

Assignees

• Haldex Brake Prod Ab

Inventors

• Harrison Dudley John
• Mellings Carl
• PIECZKO Mark
• Brightman Neil

Classifications

• B60T7/203

  with automatic brake release or reduction in case of reverse travel, e.g. by means of mechanisms mounted on the draw bar · CPC title

• B60T15/226

  Trailer brake valves · CPC title

• B60T13/263 Primary

  specially adapted for coupling with dependent systems, e.g. tractor-trailer systems · CPC title

• B60T13/265

  dependent systems, e.g. trailer systems · CPC title

• B60T13/683

  in pneumatic systems or parts thereof (in vacuum systems B60T13/72) · CPC title