Electronic-pneumatic braking system, for example for a heavy goods vehicle or articulated truck

Patent metadata

Field	Value
Publication number	US-9796365-B2
Application number	US-201415023804-A
Country	US
Kind code	B2
Filing date	Jul 31, 2014
Priority date	Sep 25, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

An electronic-pneumatic braking system for a vehicle, for example for a heavy goods vehicle or an articulated truck, includes a TCS/ESC modulator ( 1 ), enabling control functions for a traction control system (TCS) and a vehicle stability control system (ESC). The TCS/ESC modulator ( 1 ) includes a pneumatic relay valve ( 2 ), a solenoid valve ( 7 ) and a changeover valve device ( 11 ). In order to achieve a compact size and cost savings during manufacture, only control pressure can be applied to the solenoid valve ( 7 ) and to the changeover valve device ( 1 ), while only the pneumatic relay valve ( 2 ) has a large nominal size for conveying the supply pressure to at least one wheel brake and for venting the latter. As a result, the changeover valve device ( 11 ) can be structurally integrated in a TCS/ESC modulator ( 1 ) intended for carrying out the TCS/ESC functions.

First claim

The invention claimed is:

1. An electronic-pneumatic braking system for a vehicle, comprising a TCS/ESC modulator ( 1 ) performing control functions for a traction control system (TCS) and a vehicle stability control system (ESC) the TCS/ESC modulator ( 1 ) including a pneumatic relay valve ( 2 ), a solenoid valve ( 7 ) and a changeover valve device ( 11 ),
wherein the relay valve ( 2 ) has a control chamber ( 3 ) connected to an outlet ( 14 ) of the changeover valve device ( 11 ), a first port ( 4 ) as a pneumatic inlet for a supply pressure from a pressure supply device, a second port ( 5 ) as a pneumatic outlet leading to a wheel brake, and a third port ( 6 ) as a venting outlet for the wheel brake,
wherein the solenoid valve ( 7 ) has a first port ( 8 ) as a pneumatic inlet for the supply pressure from the pressure supply device, a second port ( 9 ) as a pneumatic outlet for the supply pressure, and a third port ( 10 ) as a pneumatic venting outlet,
wherein the changeover valve device ( 11 ) has a first port ( 12 ) as a pneumatic inlet, to which a control pressure of a service brake of the electronic-pneumatic braking system can be applied, a second port ( 13 ) as a pneumatic inlet, to which the supply pressure from the pressure supply device can be applied, and a third port ( 14 ) as a pneumatic outlet, via which the control pressure for the formation of an electronically controlled pneumatic wheel brake pressure or the supply pressure is fed to the control chamber ( 3 ) of the relay valve ( 2 ),
wherein the changeover valve device ( 11 ) has two control positions, of which a first control position connects the first port ( 12 ) of the changeover valve device ( 11 ), which is supplied with control pressure, to the third port ( 14 ) of the changeover valve device ( 11 ), and of which a second control position connects the second port ( 13 ) of the changeover valve device ( 11 ) to the third port ( 14 ) of the changeover valve ( 11 ),
wherein the solenoid valve is configured to supply the supply pressure to the third port ( 14 ) of the changeover valve device ( 11 ),
wherein the solenoid valve ( 7 ) is configured to be switched from a rest position into an actuating position for performing a TCS/ESC function and to set the changeover valve device ( 11 ), at least temporarily, to the second control position,
wherein, in the first control position of the changeover valve device ( 11 ), the pneumatic relay valve ( 2 ), which is supplied with the supply pressure, produces the pneumatic wheel brake pressure, which is proportional to the control pressure, and, in the second control position of the changeover valve device ( 11 ), allows the supply pressure through as wheel brake pressure, and
wherein a first control chamber ( 15 ) of the changeover valve device ( 11 ) is connected to the second port ( 13 ) of the changeover valve device ( 11 ), a second control chamber ( 16 ) of the changeover valve device ( 11 ) is connected to the third port ( 14 ) of the changeover valve device ( 11 ), and a check valve ( 17 ) blocking a flow to the second port ( 13 ) of the changeover valve device ( 11 ) is arranged between the second port ( 13 ) and the third port ( 14 ) of the changeover valve device ( 11 ).

2. The braking system as claimed in claim 1 , wherein the changeover valve device ( 11 ) is combined structurally with the TCS/ESC modulator ( 1 ).

3. The braking system as claimed in claim 2 ,
wherein the changeover valve device ( 11 ) has a valve changeover body ( 23 ), formed as a metal-reinforced elastomer component, having a substantially flat bottom ( 23 a ) that has an embedded metal reinforcement ( 25 ) in the form of a metal disk and having a sealing lip ( 24 ), which forms a cylindrical side wall,
wherein the sealing lip ( 24 ) slidably and sealingly surrounds a sliding surface ( 22 ) on a cylindrical extension ( 21 a ) on a cylindrical housing ( 21 ) and delimits a pressure space ( 28 ) configured to be supplied with the supply pressure via the second port ( 13 ) of the changeover valve device,
wherein a bottom surface ( 23 b ) of the valve changeover body ( 23 ) which faces away from the pressure space ( 28 ) is configured to be supplied with control pressure via the first port ( 12 ) of the changeover valve device, and
wherein the third port ( 14 ) of the changeover valve device opens into an annular space ( 29 ), which surrounds the valve changeover body ( 23 ) and can be connected to the first port ( 12 ) of the changeover valve device or the second port ( 13 ) of the changeover valve device, depending on the position of the valve changeover body ( 23 ).

4. The braking system as claimed in claim 2 ,
wherein the changeover valve device ( 11 ) has a valve changeover body ( 23 ), formed as a plastic-reinforced elastomer component, having a substantially flat bottom ( 23 a ) that has an embedded plastic reinforcement ( 25 ) in the form of a disk and having a sealing lip ( 24 ), which forms a cylindrical side wall,
wherein the sealing lip ( 24 ) slidably and sealingly surrounds a sliding surface ( 22 ) on a cylindrical extension ( 21 a ) on a cylindrical housing ( 21 ) and delimits a pressure space ( 28 ) that can be supplied with supply pressure via the second port ( 13 ),
wherein a bottom surface ( 23 b ) of the valve changeover body ( 23 ) which faces away from the pressure space ( 28 ) can be supplied with control pressure via the first port ( 12 ) of the changeover valve device, and in that the third port ( 14 ) of the changeover valve device opens into an annular space ( 29 ), which surrounds the valve changeover body ( 23 ) and can be connected to the first port ( 12 ) of the changeover valve device or the second port ( 13 ) of the changeover valve device, depending on the position of the valve changeover body ( 23 ).

5. The braking system as claimed in claim 1 , wherein the braking pressure is controlled by one of an electronic controller ( 32 ) or a foot brake valve.

Assignees

• Wabco Gmbh

Inventors

• Couppee Ulrich
• Kiel Bernd-Joachim

Classifications

• B60T8/3675

  integrated in modulator units · CPC title

• B60T8/342

  Pneumatic systems · CPC title

• B60T8/4818 Primary

  in pneumatic brake systems · CPC title