Granted Patent B2

US 11,377,996 · App. 16/619,292 · Granted Jul 5, 2022

Inventors: Steve Gleixner (Brookfield, WI); Robert Johnson (New Berlin, WI); Patrick Crowley (Naperville, IL); Brett Birschbach (Wauwatosa, WI)

Assignee: Briggs & Stratton, LLC

F01N13/1838F01N1/083

Abstract

Claims (50)

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 comprise a first chamber, a second chamber, a third chamber, a fourth chamber, and an outlet chamber;

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 the 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;

wherein the first chamber is in direct fluid communication with the second chamber so that the first chamber and second chamber are configured to cause the 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 chamber and the third chamber are configured to cause the exhaust gases to flow into the third chamber from the second chamber to complete a second pass, wherein the second pass is in an opposite direction from the first pass;

wherein the fourth chamber is in direct fluid communication with the third chamber so that the third chamber and the fourth chamber are configured to cause the exhaust gases to flow into the fourth chamber from the third chamber to complete a third pass, wherein the third pass is in a substantially perpendicular direction from the second pass; and

wherein the outlet chamber is in direct fluid communication with the fourth chamber so that the fourth chamber and outlet chamber are configured to cause the exhaust gases to flow into the outlet chamber from the fourth chamber to complete a fourth pass, wherein the fourth pass is in a substantially perpendicular direction from the third pass and is in the same direction as the second pass.

2. The engine of claim 1 , 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.

3. The engine of claim 2 , 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 the exhaust gases to flow through the first perforated area into the second chamber from the first chamber to complete the 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 the exhaust gases to flow through the second perforated area into the third chamber from the second chamber to complete the 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 the exhaust gases to flow through the third perforated area into the fourth chamber from the third chamber to complete the 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 the exhaust gases to flow through the fourth perforated area into the outlet chamber from the fourth chamber to complete the fourth pass.

4. The engine of claim 2 , 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.

5. The engine of claim 2 , 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.

6. The engine of claim 2 , 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.

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

8. 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 comprise a first chamber, a second chamber, a third chamber, a fourth chamber, and an outlet chamber;

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 the 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;

wherein the first chamber is in direct fluid communication with the second chamber so that the first chamber and the second chamber are configured to cause the 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 chamber and the third chamber are configured to cause the exhaust gases to flow into the third chamber from the second chamber to complete a second pass, wherein the second pass is in an opposite direction from the first pass;

wherein the fourth chamber is in direct fluid communication with the third chamber so that the third chamber and the fourth chamber are configured to cause the exhaust gases to flow into the fourth chamber from the third chamber to complete a third pass, wherein the third pass is in a substantially perpendicular direction from the second pass;

wherein the outlet chamber is in direct fluid communication with the fourth chamber so that the fourth chamber and the outlet chamber are configured to cause the exhaust gases to flow into the outlet chamber from the fourth chamber to complete a fourth pass, wherein the fourth pass is in a substantially perpendicular direction from the third pass and is the same direction as the second pass.

9. The muffler assembly of claim 8 , 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.

10. The muffler assembly of claim 9 , 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 the exhaust gases to flow through the first perforated area into the second chamber from the first chamber to complete the 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 the exhaust gases to flow through the second perforated area into the third chamber from the second chamber to complete the 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 the exhaust gases to flow through the third perforated area into the fourth chamber from the third chamber to complete the 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 the exhaust gases to flow through the fourth perforated area into the outlet chamber from the fourth chamber to complete the fourth pass.

11. The muffler assembly of claim 9 , wherein the third chamber includes the second perforated area and the third perforated area and is formed partially by a stepped chamber portion;

wherein a surface of the stepped chamber portion does not include a perforated area;

wherein the second perforated area is positioned directly below the stepped chamber portion.

12. The muffler assembly of claim 9 , 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.

13. The muffler assembly of claim 9 , wherein the outlet chamber is formed by an outlet tube that is tubular in shape;

wherein the fourth perforated area includes a fourth set of perforations formed on a curved surface of the outlet tube.

14. The muffler assembly of claim 8 , further comprising a noise dampening material retained within a cover.

Assignments (8)