Patent ID: 6052990
Filing Date: 2000-04-25
Classification: F01N,F02B,Y02T

Abstract:
A double U shaped exhaust pipe for an exhaust flow from an internal combustion engine having at least one cylinder, the exhaust flow from the engine exiting the engine in a first direction, comprising:a connecting portion for connecting the exhaust pipe to the engine;a first stage exhaust pipe portion connected to the connecting portion, the first stage portion including:a first straight pipe section having a first end and a second end, the first straight pipe section extending from the connecting portion at the first straight pipe section first end, wherein the first straight pipe section has a first inner pipe diameter;a first curved pipe section having a first end and a second end, the first curved pipe section first end being attached to the first straight pipe section second end, wherein the first curved pipe section has the first inner pipe diameter, and wherein the first curved pipe section reverses the exhaust flow, such that the exhaust flow is in a second direction upon exiting the first curved pipe portion, the second direction opposite the first direction; anda second straight section having a first end and a second end, the second straight section first end being connected to the first curved pipe section second end, wherein the second straight section has the first inner pipe diameter;a second stage exhaust pipe portion, the second stage portion including a third straight section having a first end and a second end, the third straight section first end being connected to the second straight section second end, wherein the third straight section has a second inner pipe diameter;a third stage exhaust pipe portion, the third stage portion including:a forth straight section having a first end and a second end, the forth straight section first end being connected to the third straight section second end, wherein the second straight section has the first inner pipe diameter;a second curved pipe section having a first end and a second end, the second curved pipe section first end being attached to the forth straight pipe section second end, wherein the second curved pipe section has the first inner pipe diameter, and wherein the second curved pipe section reverses the exhaust flow, such that the exhaust flow upon existing the second curved pipe section is in the first direction; anda fifth straight section having a first end and a second end, the fifth straight section first end being connected to the second curved pipe section second end, wherein the second straight section has the first inner pipe diameter; anda fourth stage exhaust pipe portion, the fourth stage portion including a sixth straight section having a first end and a second end, the sixth straight section first end being connected to the fifth straight section second end, wherein the sixth straight section has the second inner pipe diameter;wherein the second inner pipe diameter is greater than the first inner pipe diameter, such that the exhaust flow from the first inner pipe diameter into the second diameter pipe produces a vacuum pulse within the exhaust flow, the vacuum pulse returning to the engine and enhancing engine performance.