Secondary-air system and method for checking the operability of the secondary-air system

Patent metadata

Field	Value
Publication number	US-9835073-B2
Application number	US-201614989048-A
Country	US
Kind code	B2
Filing date	Jan 6, 2016
Priority date	Jan 7, 2015
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A method for checking the operability of a secondary-air system of an internal combustion engine includes measuring a first pressure between a first secondary-air pump and a first master secondary-air valve as well as a second master secondary-air valve, measuring a second pressure between a second secondary-air pump and a first slave secondary-air valve and a second slave secondary-air valve, controlling the first master secondary-air valve and the first slave secondary-air valve together, and controlling the second master secondary-air valve and the second slave secondary-air valve together. A secondary-air system includes a first control and a second control, wherein a first master secondary-air valve and a first slave secondary-air valve are controllable together by the first control and wherein a second master secondary-air valve and a second slave secondary-air valve are controllable together by the second control.

First claim

What is claimed is:

1. A secondary-air system, comprising:
a plurality of exhaust gas banks including a first master exhaust gas bank, a second master exhaust gas bank, a first slave exhaust gas bank, and a second slave exhaust gas bank;
a plurality of secondary-air pumps including a first secondary-air pump and a second secondary-air pump;
a plurality of secondary-air lines including a first secondary-air line, a second secondary-air line, a third secondary-air line, and a fourth secondary-air line, wherein, by using said secondary-air pumps, secondary air is guidable, via said secondary-air lines, to said exhaust gas banks;
a plurality of secondary-air valves including a first master secondary-air valve, a second master secondary-air valve, a first slave secondary-air valve, and a second slave secondary-air valve, wherein in each case a respective one of said secondary-air valves is assigned to a respective one of said secondary-air lines;
said first master exhaust gas bank being connected, via said first secondary-air line, to said first master secondary-air valve, said second master exhaust gas bank being connected, via said second secondary-air line, to said second master secondary-air valve, wherein, by using said first secondary-air pump, said first and said second master secondary-air valve and associated ones of said secondary-air lines can be supplied with secondary air;
said first slave exhaust gas bank being connected, via said third secondary-air line, to said first slave secondary-air valve, said second slave exhaust gas bank being connected, via said fourth secondary-air line, to said second slave secondary-air valve, wherein, by using said second secondary-air pump, said first and said second slave secondary-air valve and associated ones of said secondary-air lines can be supplied with secondary air; and
a plurality of controls including a first control and a second control, wherein, by using said first control, said first master secondary-air valve and said first slave secondary-air valve are controllable together and wherein, by using said second control, said second master secondary-air valve and said second slave secondary-air valve are controllable together.

2. The secondary-air system according to claim 1 , including:
a master engine control device and a slave engine control device; said first control being connected to said master engine control device, said second control being connected to said slave engine control device; and
said first and said second control each having an electrically actuatable switching valve.

3. A method for checking an operability of a secondary-air system of an internal combustion engine, the method comprising:
measuring a first pressure between a first secondary-air pump and a first master secondary-air valve as well as a second master secondary-air valve;
measuring a second pressure between a second secondary-air pump and a first slave secondary-air valve and a second slave secondary-air valve;
controlling the first master secondary-air valve and the first slave secondary-air valve together;
controlling the second master secondary-air valve and the second slave secondary-air valve together: and
providing the secondary-air system such that a first master exhaust gas bank is connected, via a first secondary-air line, to the first master secondary-air valve, a second master exhaust gas bank is connected, via a second secondary-air line, to the second master secondary-air valve, wherein, by using the first secondary-air pump, the first and the second master secondary-air valve and associated ones of the secondary-air lines can be supplied with secondary air, and such that a first slave exhaust gas bank is connected, via a third secondary-air line, to the first slave secondary-air valve, a second slave exhaust gas bank is connected, via a fourth secondary-air line, to the second slave secondary-air valve, wherein, by using the second secondary-air pump, the first and the second slave secondary-air valve and associated ones of the secondary-air lines can be supplied with secondary air, and providing the secondary-air system such that by using a first control, the first master secondary-air valve and the first slave secondary-air valve are controllable together, and such that by using a second control, the second master secondary-air valve and the second slave secondary-air valve are controllable together.

4. The method according to claim 3 , which comprises activating, in a first phase, both of the secondary-air pumps and opening the first master secondary-air valve, the second master secondary-air valve, the first slave secondary-air valve as well as the second slave secondary-air valve and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

5. The method according to claim 4 , which comprises:
opening, in a further phase, the first master secondary-air valve and the first slave secondary-air valve and closing the second master secondary-air valve and the second slave secondary-air valve; and
closing, in a further phase, the first master secondary-air valve and the first slave secondary-air valve and opening the second master secondary-air valve and the second slave secondary-air valve and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

6. The method according to claim 5 , which comprises carrying out the further phase only if the first pressure measured in the first phase or the second pressure measured in the first phase is outside the tolerance range.

7. The method according to claim 4 , which comprises closing, in a second phase, the first master secondary-air valve, the second master secondary-air valve, the first slave secondary-air valve as well as the second slave secondary-air valve and activating both of the secondary-air pumps or keeping both of the secondary-air pumps activated and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

8. The method according to claim 5 , which comprises closing, in a second phase, the first master secondary-air valve, the second master secondary-air valve, the first slave secondary-air valve as well as the second slave secondary-air valve and activating both of the secondary-air pumps or keeping both of the secondary-air pumps activated and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

9. The method according to claim 7 , which comprises turning off, in a third phase, both of the secondary-air pumps and keeping the first master secondary-air valve, the second master secondary-air valve, the first slave secondary-air valve as well as the second slave secondary-air valve closed and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

10. The method according to claim 8 , which comprises turning off, in a third phase, both of the secondary-air pumps and keeping the first master secondary-air valve, the second master secondary-air valve, the first slave secondary-air valve as well as the second slave secondary-air valve closed and checking whether the thereby measured first pressure is within a tolerance range and whether the measured second pressure is within a tolerance range.

11. The method according to claim 3 , which comprises providing the secondary-air system such that the first control is connected to a ma

Assignees

• Volkswagen Ag

Inventors

• Weddig Silke
• Riechert Christian
• Kirstein Oliver
• Starke Ralf

Classifications

• F01N2550/14

  Systems for adding secondary air into exhaust · CPC title

• F01N11/00

  Monitoring or diagnostic devices for exhaust-gas treatment apparatus · CPC title

• F01N3/225

  Electric control of additional air supply · CPC title

• F01N3/323

  Electrically driven air pumps · CPC title

• Y02T10/20

  Cross-Sectional Technologies · mapped topic