Exhaust gas system for an internal combustion engine

Abstract

An exhaust gas system for an internal combustion engine of a single-track vehicle can be arranged on an exhaust gas outlet of a cylinder head. A first lambda probe close to the cylinder head is provided in the exhaust gas system and is arranged before an exhaust gas cleaning system in the flow direction of an exhaust gas. A second lambda probe is provided in the exhaust gas system after the exhaust gas cleaning system in the flow direction of the exhaust gas. The second lambda probe is arranged at a maximum distance away from the exhaust gas cleaning system equal to four times the diameter of the exhaust gas cleaning system. As a result of the design, the lambda probe is arranged in the non-visible region of the single-track vehicle, while simultaneously examining the quality of the exhaust gas cleaning.

Claims

1. An exhaust-gas system for an internal combustion engine of a single-track vehicle, wherein the exhaust-gas system is arrangeable at an exhaust-gas outlet of a cylinder head of the internal combustion engine, comprising: a first lambda probe situated close to the cylinder head in the exhaust-gas system, which first lambda probe is arranged upstream of an exhaust-gas purification system in relation to a flow direction of an exhaust gas; and a second lambda probe provided in the exhaust-gas system downstream of the exhaust gas purification system in relation to the flow direction of the exhaust gas, wherein the first lambda probe is arranged in the exhaust-gas system at a distance from the cylinder head of at most ten times the diameter of the exhaust-gas outlet, the second lambda probe is arranged in the exhaust-gas system so as to be at a distance from the exhaust gas purification system of at most four times a diameter of the exhaust-gas purification system.

2. The exhaust-gas system according to claim 1, further comprising: a muffler arranged between the cylinder head and the first lambda probe.

3. The exhaust-gas system according to claim 2, wherein the muffler is a premuffler.

4. A single-track vehicle, comprising: an internal combustion engine having a cylinder head with an exhaust gas outlet; and an exhaust gas system arranged at the exhaust-gas outlet of the cylinder head of the internal combustion engine, the exhaust gas system comprising: a first lambda probe situated close to the cylinder head in the exhaust-gas system, which first lambda probe is arranged upstream of an exhaust-gas purification system in relation to a flow direction of exhaust gas; a second lambda probe provided in the exhaust-gas system downstream of the exhaust gas purification system in relation to the flow direction of the exhaust gas, wherein the first lambda probe is arranged in the exhaust-gas system at a distance from the cylinder head of at most ten times the diameter of the exhaust-gas outlet, the second lambda probe is arranged in the exhaust-gas system so as to be at a distance from the exhaust gas purification system of at most four times a diameter of the exhaust-gas purification system; and a muffler arranged between the internal combustion engine and a swinging fork of the single-track vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows a view of an internal combustion engine with an exemplary exhaust-gas system according to the invention.

DETAILED DESCRIPTION OF THE DRAWING

(2) FIG. 1 shows a view of an internal combustion engine 2 with an exhaust-gas system 1 for a single-track vehicle, such as for example a motorcycle, a moped, a moped with kick starter or a motor-assisted bicycle.

(3) The internal combustion engine 2 has a cylinder head 3, at the exhaust-gas outlet (not designated) of which an exhaust-gas system 1 is arranged. The exhaust-gas system 1 is composed substantially of an exhaust-gas pipe (not designated), in which a first lambda probe 4 (oxygen probe) is arranged close to the cylinder head. The first lambda probe 4 is situated between the cylinder head 3 and an exhaust-gas purification system 5. The exhaust-gas purification system 5, such as for example a three-way catalytic converter, is encased in the present exemplary embodiment by an additional sheet-metal paneling (not designated) as a heat shield. A flow direction of the exhaust gas is indicated by two arrows.

(4) A second lambda probe 6 (oxygen probe) is arranged in the exhaust-gas system 1 downstream of the exhaust-gas purification device 5 in relation to the flow direction of the exhaust gas. According to the invention, the second lambda probe 6 is arranged in the exhaust-gas system 1 at a distance from the exhaust-gas purification system 5 of at most four times the diameter of the exhaust-gas purification system 5. The diameter of the exhaust-gas purification system 5 is the diameter of the catalytically coated monolith without its encasement. The diameter applies to the cross section of circular exhaust-gas purification systems 5. In the case of exhaust-gas purification systems 5 of oval cross section, the spacing of four times the greatest diameter of the catalytically coated monolith applies.

(5) In one refinement of the invention, a muffler (not illustrated in the present exemplary embodiment) is arranged between the cylinder head 3 and the first lambda probe 4. This muffler is preferably a premuffler.

(6) The positioning of the first lambda probe 4 close to the cylinder head means that the first lambda probe 4 is arranged in the exhaust-gas system 1 at a distance from the cylinder head 3 of at most ten times the diameter of the exhaust-gas outlet in the cylinder head 3.

(7) In a further refinement of the invention, the muffler is arranged between the internal combustion engine and a swinging fork of a single-track vehicle (not illustrated).

(8) The embodiment according to the invention of the exhaust-gas system 1 leads to an improved exhaust-gas measurement and thus to considerably more environmentally compatible operation of the internal combustion engine 2. It is furthermore possible for future exhaust-gas standards, such as for example Euro 5, to be satisfied for single-track vehicles. What is particularly advantageous is the utilization of existing structural space in the non-visible region, with the best possible packaging compatibility.

LIST OF REFERENCE DESIGNATIONS

(9) 1 Exhaust-gas system

(10) 2 Internal combustion engine

(11) 3 Cylinder head

(12) 4 First lambda probe

(13) 5 Exhaust-gas purification system

(14) 6 Second lambda probe

(15) 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.