Motor vehicle with internal combustion engine and catalytic...

Details Motor vehicle with internal combustion engine and catalytic... Motor vehicle with internal combustion engine and catalytic...

2000-02-10

2001-05-01

Denion, Thomas (Department: 3748)

Power plants

Internal combustion engine with treatment or handling of...

By means producing a chemical reaction of a component of the...

C060S287000, C060S289000, C060S292000, C060S324000, C060S323000

Reexamination Certificate

active

06223527

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to a motor vehicle with an internal combustion engine, in which the exhaust gases are passed via a catalytic converter, the exhaust lines from the individual cylinders being combined into a collecting line, from which two feed lines, in particular two feed lines with different cross sections lead to the catalytic converter. The distance between one of the feed lines and the catalytic converter is greater and this feed line can be shut off by means of a valve.
SUMMARY OF THE INVENTION
An arrangement of a similar kind is disclosed in DE-A 42 18 834. Here, the arrangement, with an in-line engine arranged transversely in a motor vehicle, is such that two lines of equal length but different cross sections are passed from the internal combustion engine directly to the catalytic converter, which is arranged in the rear area of the motor vehicle. A shut-off valve is provided in the line with the larger cross section, and the line with the larger cross section is thus shut off in the warm-up phase and the exhaust gases are fed to the catalytic converter only through the line with the smaller cross section.
In DE-A 25 34 39 998, provision is made, where there are two different lines for feeding the exhaust gases to the catalytic converter, for making the feed lines of different lengths.
During lean combustion, the relatively high temperature in the reaction zone leads to increased levels of NO
x
. The splitting of N
2
and hence the formation of NO
x
increases exponentially with temperature. The combustion temperature and hence the proportion of NO
x
can also be reduced by exhaust gas recirculation in the case of direct injection of gasoline.
It was an object of the invention, on the one hand, to ensure rapid heating of the catalytic converter after starting of the internal combustion engine without loss of the necessary cooling for feeding the exhaust gases to the catalytic converter during continuous operation of the motor vehicle. On the other hand, the intention is to further reduce the proportion of NO
x
in the case of gasoline internal combustion engines which employ the lean combustion method, by means of a structural modification of the exhaust-gas recirculation system.
This object is achieved by the fact that the lines for feeding the exhaust gases to the catalytic converter are of different lengths, the longer feed line having an arc-shaped region and then running counter to the direction of travel to the catalytic converter, which is arranged underneath the passenger compartment, the other feed line providing a short connection between a region of the collecting line and an exhaust-line region adjacent to the catalytic converter, and at least one exhaust-gas recirculation line branching off from the longer feed line.
This arrangement ensures that a positive solution can be offered for the “package” within the motor vehicle for the exhaust line and the catalytic converter; the longer feed line is situated in an area of the motor vehicle in which optimum cooling is possible. Nevertheless, by shutting off the feed line of larger cross section when starting the motor vehicle, the other feed line will ensure rapid heating of the catalytic converter. Taking the exhaust gas from a point on the longer feed line ensures that the exhaust gas removed is at a reduced temperature in all operating modes. This “cooled” exhaust gas can be used to further reduce the combustion temperature. Moreover, reduced temperature results in a higher exhaust gas recirculation rate, a reduction in consumption and higher efficiency.
As a development of the invention, the internal combustion engine can be arranged with the in-line cylinders transverse to the direction of travel and the exhaust manifold from the cylinders can be located behind the internal combustion engine, as seen in the direction of travel. This results in particularly favorable space conditions and the routing of the exhaust lines is simplified.
As a development of the invention, the valve for shutting off the longer connecting line can be arranged in the region of the bend in the exhaust line, ahead of the internal combustion engine as seen in the direction of travel; this opens up additional possibilities for cooling in this arrangement, something which is important for correct operation. In this case, the removal point for the exhaust gas to be recirculated is arranged between the valve and the catalytic converter.
It is also advantageous to arrange this valve ahead of or after the bend, as seen in the direction of flow of the exhaust gases, depending on where the possibilities for cooling are better.
A proportional valve is preferably arranged in the exhaust-gas recirculation line.


REFERENCES:
patent: 3545414 (1970-12-01), Thompson
patent: 5832721 (1998-11-01), Cullen
patent: 5855113 (1999-01-01), Cullen et al.
patent: 5937637 (1999-08-01), Fujishita et al.
patent: 5937640 (1999-08-01), Krzykowski et al.
patent: 6003310 (1999-12-01), Maysr et al.

Affiliated with

Also associated with

Rating

Motor vehicle with internal combustion engine and catalytic... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Motor vehicle with internal combustion engine and catalytic..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Motor vehicle with internal combustion engine and catalytic... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2439363