Assembly and method for determining lambda values

Abstract

An assembly for determining lambda values of an exhaust gas of an internal combustion engine is provided. The internal combustion engine is attached to an exhaust gas treatment device with at least one first catalyst and a second catalyst. Additionally, the assembly has the following: a first lambda sensor in a first removal line, wherein the first removal line is designed to remove a part of the exhaust gas upon entering the first catalyst and conduct same back into the exhaust gas treatment device after the exhaust gas passes the first lambda sensor, and the first lambda sensor and at least one part of the first removal line are arranged outside of the exhaust gas treatment device; and a second lambda sensor in a second removal line, wherein the second removal line is designed to remove a part of the exhaust gas between the first catalyst and the second catalyst and conduct same back into the exhaust gas treatment device after the exhaust gas passes the second lambda sensor, and the second lambda sensor and at least one part of the second removal line are arranged outside of the exhaust gas treatment device.

Claims

1. An assembly for determining lambda values of an exhaust gas of an internal combustion engine, wherein the internal combustion engine is attached to an exhaust gas treatment apparatus including at least one first catalytic converter and at least one second catalytic converter, the assembly comprising: a first lambda sensor in a first extraction line, wherein the first extraction line is designed to extract a portion of the exhaust gas at a point in an interior of the first catalytic converter at a distance from an edge of the first catalytic converter and to return the portion of the exhaust gas to the first catalytic converter after it passes the first lambda sensor, where the first lambda sensor and at least a portion of the first extraction line are arranged outside the exhaust gas treatment apparatus; and a second lambda sensor in a second extraction line, wherein the second extraction line is designed to extract a portion of the exhaust gas at a center of a stream of the exhaust gas between the first catalytic converter and the second catalytic converter and to return the portion of the exhaust gas to the second catalytic converter after it passes the second lambda sensor, where the second lambda sensor and at least a portion of the second extraction line are arranged outside the exhaust gas treatment apparatus.

2. The assembly according to claim 1, wherein at least one of the first and second extraction lines extends at least partially into the exhaust gas treatment apparatus.

3. The assembly according to claim 2, wherein at least one of the first and second extraction lines has a plurality of line branches.

4. The assembly according to claim 1, wherein a plurality of extraction openings are provided on at least one of the first and second extraction lines.

5. The assembly according to claim 4, further comprising: at least one closure apparatus for closing at least one of the plurality of extraction openings.

6. The assembly according to claim 4, wherein at least one of the first and second extraction lines has a plurality of line branches.

7. The assembly according to claim 6, further comprising: a third lambda sensor in a third extraction line, wherein the third extraction line is designed to extract a portion of the exhaust gas as it exits from the second catalytic converter and to return the portion of the exhaust gas to an exhaust gas line after it passes the third lambda sensor downstream of the exhaust gas treatment apparatus, and the third lambda sensor and at least a portion of the third extraction line are arranged outside the exhaust gas treatment apparatus.

8. The assembly according to claim 7, wherein at least one of the following sensors is integrated into at least one of the first, second, and third extraction lines: temperature sensor, pressure sensor, pollutant sensor, or particle sensor.

9. The assembly according to claim 1, wherein at least one of the first and second extraction lines has a plurality of line branches.

10. The assembly according to claim 1, further comprising: a third lambda sensor in a third extraction line, wherein the third extraction line is designed to extract a portion of the exhaust gas as it exits from the second catalytic converter and to return the portion of the exhaust gas to an exhaust gas line after it passes the third lambda sensor downstream of the exhaust gas treatment apparatus, and the third lambda sensor and at least a portion of the third extraction line are arranged outside the exhaust gas treatment apparatus.

11. The assembly according to claim 1, wherein at least one of the following sensors is integrated into at least one of the first and second extraction lines: temperature sensor, pressure sensor, pollutant sensor, or particle sensor.

12. A motor vehicle comprising: an internal combustion engine with an exhaust gas treatment apparatus comprising at least one first catalytic converter and at least one second catalytic converter connected thereto, and an assembly for determining lambda values according to claim 1.

13. The assembly according to claim 1, wherein the assembly uses a first lambda value from the first lambda sensor for regulating a fuel/air mixture of the internal combustion engine and uses a deviation between the first lambda value from the first lambda sensor and a second lambda value from the second lambda sensor to compensate for a shift in a characteristic curve of the first lambda sensor.

14. The assembly according to claim 1, wherein the first lambda sensor is embodied as a wideband sensor and the second lambda sensor is embodied as a discrete-level sensor.

15. A method for determining lambda values of an exhaust gas of an internal combustion engine, wherein the internal combustion engine is attached to an exhaust gas treatment apparatus comprising at least one first catalytic converter and at least one second catalytic converter, the method comprising the acts of: a) extracting a portion of the exhaust gas at a point in an interior of the first catalytic converter at a distance from an edge of the first catalytic converter; b) measuring a first lambda value by a first lambda sensor from the exhaust gas which was extracted in act a); c) returning the exhaust gas which was extracted in act a) to the first catalytic converter; d) extracting a portion of the exhaust gas at a center of a stream of the exhaust gas between the first catalytic converter and the second catalytic converter; e) measuring a second lambda value by a second lambda sensor from the exhaust gas which was extracted in act d); and f) returning the exhaust gas which was extracted in act d) to the second catalytic converter.

16. The method according to claim 15 further comprising the acts of: g) using the first lambda value from the first lambda sensor to regulate a fuel/air mixture of the internal combustion engine; and h) using a deviation between the first lambda value from the first lambda sensor and the second lambda value from the second lambda sensor to compensate for a shift in a characteristic curve of the first lambda sensor.

17. The method according to claim 15, wherein the first lambda sensor is embodied as a wideband sensor and the second lambda sensor is embodied as a discrete-level sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic illustration of a motor vehicle having an assembly for determining lambda values.

(2) FIG. 2 is an enlarged schematic illustration of a portion of the assembly from FIG. 1.

DETAILED DESCRIPTION OF THE DRAWINGS

(3) FIG. 1 shows a motor vehicle 1 having an internal combustion engine 2. An exhaust gas treatment apparatus 4 including at least one first catalytic converter 5 and at least one second catalytic converter 6 is connected to the internal combustion engine 2 via an exhaust gas line 3. A direction of flow of the exhaust gas is indicated by arrows. The motor vehicle 1 further has an assembly 7 for determining lambda values. The assembly 7 includes a first lambda sensor 10 in a first extraction line 8. The first lambda sensor 10 is embodied as a wideband sensor. The first extraction line 8 is designed to extract a portion of the exhaust gas as it enters the first catalytic converter 5 and to return said portion of the exhaust gas to the first catalytic converter 5 (which is part of the exhaust gas treatment apparatus 4) after it passes the first lambda sensor 10. The first lambda sensor 10 and a portion of the first extraction line 8 are arranged outside the exhaust gas treatment apparatus 4. Furthermore, the assembly 7 includes a second lambda sensor 11 in a second extraction line 9. The second lambda sensor 11 is embodied as a discrete-level sensor. The second extraction line 9 is designed to extract a portion of the exhaust gas between the first catalytic converter 5 and the second catalytic converter 6 and to return said portion of the exhaust gas to the second catalytic converter 6 (which is part of the exhaust gas treatment apparatus 4) after it passes the second lambda sensor 11. The second lambda sensor 11 and a portion of the second extraction line 9 are arranged outside the exhaust gas treatment apparatus 4. The first extraction line 8 and the second extraction line 9 extend into the exhaust gas treatment apparatus 4.

(4) The assembly 7 further includes a third lambda sensor 20 in a third extraction line 19. The third extraction line 19 is designed to extract a portion of the exhaust gas as it exits from the second catalytic converter 6 and to return said portion of the exhaust gas to the exhaust gas line 3 after it passes the third lambda sensor 20 downstream of the exhaust gas treatment apparatus 4. The third lambda sensor 20 and at least a portion of the third extraction line 19 are arranged outside the exhaust gas treatment apparatus 4.

(5) A temperature sensor 21 is integrated into the first extraction line 8. A pressure sensor 22 is integrated into the second extraction line 9. A pollutant sensor 23 and a particle sensor 24 are integrated into the third extraction line 19.

(6) FIG. 2 shows an enlarged schematic illustration of a portion of the assembly 7 from FIG. 1. A portion of the exhaust gas line 3, a portion of the exhaust gas treatment apparatus 4 with a portion of the first catalytic converter 5 and also a portion of the first extraction line 8 with the first lambda sensor 10 can be seen in said FIG. 2. The first extraction line 8 has a first line branch 12 and a second line branch 13. A first extraction opening 14, a second extraction opening 15 and a third extraction opening 16 are provided in the first line branch 12. The first extraction opening 14 and the second extraction opening 15 are arranged on a side of the extraction line toward which exhaust gas flows. The direction of flow of the exhaust gas is indicated by an arrow. A fourth extraction opening 17 is provided in the second line branch 13. Furthermore, the assembly 7 has a closure apparatus 18 for closing the fourth extraction opening 17.

LIST OF REFERENCE SYMBOLS

(7) 1 Motor vehicle 2 Internal combustion engine 3 Exhaust gas line 4 Exhaust gas treatment apparatus 5 First catalytic converter 6 Second catalytic converter 7 Assembly 8 First extraction line 9 Second extraction line 10 First lambda sensor 11 Second lambda sensor 12 First line branch 13 Second line branch 14 First extraction opening 15 Second extraction opening 16 Third extraction opening 17 Fourth extraction opening 18 Closure apparatus 19 Third extraction line 20 Third lambda sensor 21 Temperature sensor 22 Pressure sensor 23 Pollutant sensor 24 Particle sensor

(8) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.