Exhaust system for an internal combustion engine and method for operating the exhaust system

Patent metadata

Field	Value
Publication number	US-9945276-B2
Application number	US-201715470028-A
Country	US
Kind code	B2
Filing date	Mar 27, 2017
Priority date	May 15, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

An exhaust system is provided for an internal combustion engine having at least a first and a second cylinder, wherein the first cylinder is assigned a first exhaust gas pipe and the second cylinder is assigned a second exhaust gas pipe. The first exhaust gas pipe is assigned a first muffler, and the second exhaust gas pipe is assigned a second muffler. A first damping pipe branches off from the first exhaust gas pipe upstream of a first shut-off element. The damping pipe firstly opens into a first reflection chamber and is subsequently led through the first muffler and opens into the second exhaust gas manifold downstream of a second shut-off element. A second damping pipe branches off from the second exhaust gas pipe upstream of a second shut-off element. The second damping pipe firstly opens into a second reflection chamber and is subsequently led through the second muffler and opens into the first exhaust gas pipe downstream of the first shut-off element.

First claim

What is claimed is:

1. An exhaust system for an internal combustion engine having at least a first and a second cylinder, the exhaust system comprising:
a first exhaust pipe assigned to the first cylinder;
a second exhaust pipe assigned to the second cylinder;
a first muffler assigned to the first exhaust pipe;
a second muffler assigned to the second exhaust pipe;
a first damping pipe branching off of the first exhaust pipe upstream of a first shut-off element in the first exhaust pipe;
a second damping pipe branching off of the second exhaust pipe upstream of a second shut-off element in the second exhaust pipe, wherein
the first damping pipe leads first into a first reflection chamber and subsequently extends through the first muffler and leads into the second exhaust pipe downstream of the second shut-off element in a portion of the second exhaust pipe located in a fourth reflection chamber,
the second damping pipe leads first into a second reflection chamber and subsequently extends through the second muffler and leads into the first exhaust pipe downstream of the first shut-off element in a portion of the first exhaust pipe located in a third reflection chamber,
the first exhaust pipe is connected in an exhaust-gas-carrying manner, by way of perforations in the second exhaust pipe, with the third reflection chamber, and
the second exhaust pipe is connected in an exhaust-gas-carrying manner by way of perforations in the first exhaust pipe, with the fourth reflection chamber.

2. The exhaust system according to claim 1 , wherein
at least one of the first and the third reflection chambers are connected with one another in an exhaust-gas-carrying manner and the second and the fourth reflection chambers are connected with one another in an exhaust-gas-carrying manner.

3. The exhaust system according to claim 1 , wherein
at least one of the first and the third reflection chambers are connected with one another in an exhaust-gas-carrying manner and the second and the fourth reflection chambers are connected with one another in an exhaust-gas-carrying manner.

4. The exhaust system according to claim 1 , further comprising a common housing in which the first and the second mufflers are arranged.

5. The exhaust system according to claim 4 , wherein the first and the second reflection chambers are arranged in the common housing.

6. The exhaust system according to claim 5 , wherein the third and the fourth reflection chambers are arranged in the common housing.

7. The exhaust system according to claim 4 , wherein the third and the fourth reflection chambers are arranged in the common housing.

8. A method of operating an exhaust system for an internal combustion engine having at least a first and a second cylinder, the method comprising the acts of:
providing a first exhaust pipe assigned to the first cylinder;
providing a second exhaust pipe assigned to the second cylinder;
providing a first muffler assigned to the first exhaust pipe;
providing a second muffler assigned to the second exhaust pipe;
providing a first damping pipe branching off of the first exhaust pipe upstream of a first shut-off element in the first exhaust pipe;
providing a second damping pipe branching off of the second exhaust pipe upstream of a second shut-off element in the second exhaust pipe, wherein the first damping pipe leads first into a first reflection chamber and subsequently extends through the first muffler and leads into the second exhaust pipe downstream of the second shut-off element in a portion of the second exhaust pipe located in a fourth reflection chamber, the second damping pipe first leads into a second reflection chamber and subsequently extends through the second muffler and leads into the first exhaust pipe downstream of the first shut-off element in a portion of the first exhaust pipe located in a third reflection chamber, the first exhaust pipe is connected in an exhaust-gas-carrying manner, by way of perforations in the second exhaust pipe, with the third reflection chamber, and the second exhaust pipe is connected in an exhaust-gas-carrying manner by way of perforations in the first exhaust pipe, with the fourth reflection chamber; and
opening the first and the second shut-off elements for minimal muffling.

9. The method according to claim 8 , further comprising the act of:
opening the first shut-off element and closing the second shut-off element for medium muffling.

10. The method according to claim 9 , further comprising the act of:
closing the first and the second shut-off elements for maximum muffling.

11. The method according to claim 8 , further comprising the act of:
closing the first and the second shut-off elements for maximum muffling.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Drees Rainer
• Eichmueller Christian

Classifications

• F01N1/083 Primary

  using transversal baffles defining a tortuous path for the exhaust gases or successively throttling exhaust gas flow · CPC title

• F01N13/02 Primary

  having two or more separate silencers in series · CPC title

• F01N1/166

  for changing the flow path through the silencer or for adjusting the dimensions of a chamber or a pipe (F01N1/165 takes precedence) · CPC title

• F01N2470/02

  Tubes being perforated · CPC title

• F01N1/168

  for controlling or modifying silencing characteristics only · CPC title