Muffler with baffle defining multiple chambers

Patent metadata

Field	Value
Publication number	US-2020141301-A1
Application number	US-201816619292-A
Country	US
Kind code	A1
Filing date	Jun 6, 2018
Priority date	Jun 9, 2017
Publication date	May 7, 2020
Grant date	—

Abstract

An internal combustion engine includes an engine block including a cylinder and a muffler assembly configured to receive exhaust gases from the cylinder. The muffler assembly includes a housing defining an interior volume and including an exhaust inlet and an exhaust outlet, and a baffle assembly positioned within the interior volume. The baffle assembly includes a plurality of chambers in fluid communication with each other. The plurality of chambers are in fluid communication with the exhaust inlet and the exhaust outlet so that the plurality of chambers are configured to cause exhaust gases to be directed through the muffler assembly from the exhaust inlet to the exhaust outlet through four passes in the baffle assembly before exiting through the exhaust outlet.

First claim

What is claimed is:

1 . An internal combustion engine, comprising:
an engine block including a cylinder; and a muffler assembly configured to receive exhaust gases from the cylinder, the muffler assembly comprising:
a housing defining an interior volume and including an exhaust inlet and an exhaust outlet; and
a baffle assembly positioned within the interior volume, the baffle assembly comprising a plurality of chambers in fluid communication with each other;
wherein the plurality of chambers are in fluid communication with the exhaust inlet and the exhaust outlet so that the plurality of chambers are configured to cause exhaust gases to be directed through the muffler assembly from the exhaust inlet to the exhaust outlet through four passes in the baffle assembly before exiting through the exhaust outlet.

2 . The engine of claim 1 , wherein the plurality of chambers comprise a first chamber, a second chamber, a third chamber, a fourth chamber, and an outlet chamber.

3 . The engine of claim 2 , wherein the first chamber is in direct fluid communication with the second chamber so that the first and second chambers are configured to cause exhaust gases to flow into the first chamber and the second chamber from the exhaust inlet to complete a first pass;
wherein the third chamber is in direct fluid communication with the second chamber so that the second and third chambers are configured to cause exhaust gases to flow into the third chamber from the second chamber to complete a second pass; wherein the fourth chamber is in direct fluid communication with the third chamber so that the third and fourth chambers are configured to cause exhaust gases to flow into the fourth chamber from the third chamber to complete a third pass; wherein the outlet chamber is in direct fluid communication with the fourth chamber so that the fourth and outlet chambers are configured to cause exhaust gases to flow into the outlet chamber from the fourth chamber to complete a fourth pass.

4 . The engine of claim 3 , wherein the second pass is in an opposite direction from the first pass;
wherein the third pass is in a substantially perpendicular direction from the second pass; wherein the fourth pass is in a substantially perpendicular direction from the third pass and is the same direction as the second pass.

5 . The engine of claim 2 , wherein the baffle assembly further comprises a plurality of perforated areas including a first perforated area, a second perforated area, a third perforated area, and a fourth perforated area.

6 . The engine of claim 5 , wherein the first chamber is in direct fluid communication with the second chamber via the first perforated area so that the first and second chambers are configured to cause exhaust gases to flow through the first perforated area into the second chamber from the first chamber to complete a first pass;
wherein the second chamber is in direct fluid communication with the third chamber via the second perforated area so that the second and third chambers are configured to cause exhaust gases to flow through the second perforated area into the third chamber from the second chamber to complete a second pass; wherein the third chamber is in direct fluid communication with the fourth chamber via the third perforated area so that the third and fourth chambers are configured to cause exhaust gases to flow through the third perforated area into the fourth chamber from the third chamber to complete a third pass; wherein the fourth chamber is in direct fluid communication with the outlet chamber via the fourth perforated area so that the fourth and outlet chambers are configured to cause exhaust gases to flow through the fourth perforated area into the outlet chamber from the fourth chamber to complete a fourth pass.

7 . The engine of claim 5 , wherein the third chamber includes the second set of perforations and the third set of perforations and is formed partially by a stepped chamber portion;
wherein a surface of the stepped chamber portion does not include perforations; wherein the second set of perforations are positioned directly below the stepped chamber portion.

8 . The engine of claim 5 , wherein the first perforated area is positioned opposite from the second perforated area within the second chamber;
wherein the second perforated area is positioned opposite from the third perforated area within the third chamber; wherein the third perforated area is positioned opposite from the fourth perforated area within the fourth chamber; wherein the fourth perforated area is positioned opposite from the exhaust outlet within the outlet chamber.

9 . The engine of claim 5 , wherein the outlet chamber is formed by an outlet tube that is tubular in shape;
wherein the fourth set of perforations are formed on a curved surface of the outlet tube.

10 . The engine of claim 1 , further comprising a noise dampening material retained within the cover.

11 . A muffler assembly configured to dampen noise of exhaust gases flowing therethrough, the muffler assembly comprising:
a housing defining an interior volume and including an exhaust inlet and an exhaust outlet; and a baffle assembly positioned within the interior volume, the baffle assembly comprising a plurality of chambers in fluid communication with each other; wherein the plurality of chambers are in fluid communication with the exhaust inlet and the exhaust outlet so that the plurality of chambers are configured to cause exhaust gases to be directed through the muffler assembly from the exhaust inlet to the exhaust outlet through four passes in the baffle assembly before exiting through the exhaust outlet.

12 . The muffler assembly of claim 11 , wherein the plurality of chambers comprise a first chamber, a second chamber, a third chamber, a fourth chamber, and an outlet chamber.

13 . The muffler assembly of claim 12 , wherein the first chamber is in direct fluid communication with the second chamber so that the first and second chambers are configured to cause exhaust gases to flow into the first chamber and the second chamber from the exhaust inlet to complete a first pass;
wherein the third chamber is in direct fluid communication with the second chamber so that the second and third chambers are configured to cause exhaust gases to flow into the third chamber from the second chamber to complete a second pass; wherein the fourth chamber is in direct fluid communication with the third chamber so that the third and fourth chambers are configured to cause exhaust gases to flow into the fourth chamber from the third chamber to complete a third pass; wherein the outlet chamber is in direct fluid communication with the fourth chamber so that the fourth and outlet chambers are configured to cause exhaust gases to flow into the outlet chamber from the fourth chamber to complete a fourth pass.

14 . The muffler assembly of claim 13 , wherein the second pass is in an opposite direction from the first pass;
wherein the third pass is in a substantially perpendicular direction from the second pass; wherein the fourth pass is in a substantially perpendicular direction from the third pass and is the same direction as the second pass.

15 . The muffler assembly of claim 12 , wherein the baffle assembly further comprises a plurality of perforated areas including a first perforated area, a second perforated area, a third perforated area, and a fourth perforated area.

16 . The muffler assembly of claim 15 , wherein the first chamber is in direct fluid communication with the second chamber via t

Assignees

• Briggs & Stratton Corp

Inventors

• Gleixner Steve
• Johnson Robert
• Crowley Patrick
• Birschbach Brett

Classifications

• F01N1/089

  using two or more expansion chambers in series (F01N1/083, F01N1/084, F01N1/086 take precedence) · CPC title

• F01N2470/04

  characterised by shape, disposition or dimensions of apertures · CPC title

• F01N1/083 Primary

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

• F01N2590/06

  for hand-held tools or portables devices · CPC title

• F01N2470/06

  Tubes being formed by assembly of stamped or otherwise deformed sheet-metal · CPC title