Exhaust sound attenuation device

Patent metadata

Field	Value
Publication number	US-11434794-B2
Application number	US-201916433830-A
Country	US
Kind code	B2
Filing date	Jun 6, 2019
Priority date	Jun 6, 2019
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

An exhaust muffler for an internal combustion engine includes a housing. A plurality of partitions are disposed within the housing, defining a plurality of chambers. An inlet pipe and an outlet pipe are also disposed within the housing and both the inlet and outlet pipes include a perforated region. The perforated region permits fluid communication between the inlet pipe, outlet pipe and the plurality of chambers. To attenuate engine noise, the perforated regions of the inlet and outlet pipes are positioned at opposite ends of the housing, forcing the exhaust gas to pass through each of the plurality of partitions and chambers, thereby damping the sound waves with minimum effect on engine back pressure levels. Alternatively, the perforated regions of the inlet and outlet pipes may be aligned in a cross-flow chamber.

First claim

What is claimed is:

1. An exhaust muffler for an internal combustion engine, comprising:
a housing including an exterior wall, a concentric interior wall, a first end cap and a second end cap opposite the first end cap;
a plurality of partitions disposed within the housing defining a plurality of chambers, the plurality of partitions including a perforated first end plate disposed proximate to the first end cap, a perforated second end plate disposed proximate to the second end cap, and a plurality of baffles disposed between the perforated first end plate and the perforated second end plate;
a first insulation material disposed between the first end cap and the perforated first end plate, the first insulation material adjacent to the perforated first end plate and adjacent to the first end cap;
an inlet pipe disposed within the interior wall and extending through the first end cap, through the plurality of partitions, through the plurality of chambers, and through the second end cap, a portion of the inlet pipe being perforated; and
an outlet pipe disposed within the interior wall and extending through the second end cap, through the plurality of partitions, through the plurality of chambers, and through the first end cap, a portion of the outlet pipe being perforated.

2. The exhaust muffler of claim 1 , further including an inlet plug installed in the inlet pipe proximate the second end cap, and an outlet plug installed in the outlet pipe proximate the first end cap.

3. The exhaust muffler of claim 2 , wherein the perforated portion of the inlet pipe is located proximate the inlet plug and the perforated portion of the outlet pipe is located proximate the outlet plug.

4. The exhaust muffler of claim 1 , wherein at least one of the plurality of baffles located between the first end plate and the second end plate is perforated.

5. The exhaust muffler of claim 4 , wherein a second insulation material is disposed between the second end plate and the second end cap, and a third insulation material is disposed between the interior wall and the exterior wall.

6. The exhaust muffler of claim 1 , wherein the first insulation material is comprised of fiberglass.

7. The exhaust muffler of claim 5 , wherein each of the plurality of partitions is dimensioned to fit within the exterior wall, such that each of the plurality of partitions extends radially through the interior wall and the third insulation material.

8. The exhaust muffler of claim 1 , wherein a length of the inlet pipe and a length of the outlet pipe are equivalent, and the inlet pipe and outlet pipe are arranged parallel and planar to each other.

9. An exhaust muffler for an internal combustion engine, comprising:
a housing including an exterior wall, a concentric interior wall, a first end cap and a second end cap opposite the first end cap;
a plurality of partitions disposed within the housing and defining a plurality of chambers including at least a first resonator chamber proximate to the first end cap, a second resonator chamber proximate to the second end cap, and a cross-flow chamber positioned between the first resonator chamber and the second resonator chamber, the plurality of partitions including a perforated first end plate disposed proximate to the first end cap, a perforated second end plate disposed proximate to the second end cap, and a plurality of baffles disposed between the perforated first end plate and the perforated second end plate;
a first insulation material disposed between the first end cap and the perforated first end plate, the first insulation material adjacent to the perforated first end plate and adjacent to the first end cap;
an inlet pipe disposed within the interior wall and extending through the first end cap, through the first resonator chamber, through the cross-flow chamber and into the second resonator chamber, a portion of the inlet pipe disposed within the cross-flow chamber being perforated; and
an outlet pipe disposed within the interior wall and extending through the second end cap, through the second resonator chamber, through the cross-flow chamber and into the first resonator chamber, a portion of the outlet pipe disposed within the cross-flow chamber being perforated.

10. The exhaust muffler of claim 9 , wherein portions of the inlet pipe and the outlet pipe disposed within the first resonator chamber and the second resonator chamber are solid.

11. The exhaust muffler of claim 9 , wherein the cross-flow chamber is positioned proximate the second end cap, such that a volume of the first resonator chamber is larger than a volume of the second resonator chamber.

12. The exhaust muffler of claim 9 , wherein the plurality of baffles includes a first solid baffle separating the first resonator chamber and the cross-flow chamber, and a second solid baffle separating the second resonator chamber and the cross-flow chamber.

13. The exhaust muffler of claim 12 , wherein a second insulation material is disposed between the second end plate and the second end cap, and a third insulation material is disposed between the interior wall and the exterior wall.

14. The exhaust muffler of claim 9 , wherein the first insulation material is comprised of fiberglass.

15. The exhaust muffler of claim 13 , wherein each of the plurality of partitions is dimensioned to fit within the exterior wall, such that each of the plurality of partitions extends radially through the interior wall and the third insulation material.

16. The exhaust muffler of claim 9 , wherein a length of the inlet pipe and a length of the outlet pipe are equivalent, and the inlet pipe and the outlet pipe are arranged parallel and planar to each other.

17. An engine system, the engine system comprising:
an engine having at least one engine cylinder, each engine cylinder having a combustion chamber, a piston, and an exhaust valve for release of exhaust gases; and
an exhaust system in fluid communication with the engine, the exhaust system including an exhaust pipe and an exhaust muffler, the exhaust muffler including
a housing including an exterior wall, a concentric interior wall, a first end cap and a second end cap opposite the first end cap;
a first perforated end plate proximate to the first end cap;
a second perforated end plate proximate to the second end cap;
a plurality of baffles positioned between the first perforated end plate and the second perforated end plate;
a first insulation material disposed between the first end cap and the perforated first end plate, the first insulation material adjacent to the perforated first end plate and adjacent to the first end cap;
an inlet pipe in fluid communication with the exhaust pipe, the inlet pipe disposed within the interior wall and extending through the first end cap, through the first end plate, and through the plurality of baffles, a portion of the inlet pipe being perforated; and
an outlet pipe disposed within the interior wall and extending through the second end cap, through the second end plate, and through the plurality of baffles, a portion of the outlet pipe being perforated.

18. The engine system of claim 17 , wherein a second insulation material is disposed between the second end plate and the second end cap, and a third insulation material is disposed between the interior wall and the exterior wall.

19. The engine system of claim 18 , wherein the first insulation material is comprised of fiberglass.

20. The engine system of claim 17 , wherein a length of the inlet pipe and a length of the o

Assignees

• Caterpillar Inc

Inventors

• Greif Andrew
• Nathak Subhro
• Hasan Saad
• Xiao Peter
• Bobchik Joseph

Classifications

• F01N2310/02

  Mineral wool, e.g. glass wool, rock wool, asbestos or the like · CPC title

• F01N13/14

  having thermal insulation {(exhaust manifolds F01N13/102)} · CPC title

• F01N1/082 Primary

  by passing the exhaust gases through porous members · CPC title

• F01N2470/24

  Concentric tubes or tubes being concentric to housing, e.g. telescopically assembled · CPC title

• G10K11/162

  Selection of materials · CPC title