Granted Patent B2

US 8,166,752 · App. 12/323,718 · Granted May 1, 2012

Assignee: GM Global Technology Operations LLC

Abstract

Claims (20)

1. An exhaust gas cooling apparatus, comprising:

a first fluid conduit;

a variable nozzle defining an opening disposed at one end of the first fluid conduit, the variable nozzle being defined by a shape memory alloy extending from the first fluid conduit; and

a second fluid conduit having an inlet end and an outlet end, the variable nozzle being disposed in the second fluid conduit proximate to the inlet end of the second fluid conduit such that a fluid inlet opening is disposed about an outer periphery of the variable nozzle and an inner surface of the inlet end of the second fluid conduit, the shape memory alloy varying the size of the variable nozzle opening by moving toward or away from a center line of the first fluid conduit in response to a temperature of an exhaust gas flowing through the first fluid conduit, such that the fluid inlet opening increases in area when the variable nozzle moves toward the center line of the first fluid conduit and the fluid inlet opening decreases in area when the variable nozzle moves away from the center line of the first fluid conduit.

2. The exhaust cooling apparatus as in claim 1 , wherein the first fluid conduit is secured to the second fluid conduit by a plurality of stand offs configured to provide flow paths therebetween.

3. The exhaust cooling apparatus as in claim 1 , wherein the second fluid conduit further comprises a central portion defining, between the inlet end and the outlet end, a venturi.

4. The exhaust cooling apparatus as in claim 3 , wherein the first fluid conduit is secured to the second fluid conduit by a plurality of stand offs configured to provide flow paths therebetween.

5. The exhaust cooling apparatus as in claim 1 , wherein the first fluid conduit is configured for attachment to an exhaust pipe of a vehicle exhaust system and an exhaust backpressure in the first fluid conduit increases when the shape memory alloy moves toward the center line of the first fluid conduit and the exhaust backpressure in the first fluid conduit decreases when the shape memory alloy moves away from the center line of the first fluid conduit.

6. The exhaust cooling apparatus as in claim 1 , wherein a portion of the inlet end of the second fluid conduit is defined by a second shape memory alloy the second shape memory alloy varying the size of the inlet end of the second fluid conduit by moving toward or away from the center line of the first fluid conduit in response to the temperature of the exhaust gas flowing through the first fluid conduit.

7. The exhaust cooling apparatus as in claim 6 , wherein the second fluid conduit further comprises a central portion defining, between the inlet end and the outlet end, a venturi.

8. The exhaust cooling apparatus as in claim 7 , wherein the first fluid conduit is secured to the second fluid conduit by a plurality of stand offs configured to provide flow paths therebetween and the second shape memory alloy is configured to move in a direction opposite to the shape memory alloy of the first fluid conduit in response to the temperature of the exhaust gas flowing through the first fluid conduit.

9. An exhaust system for a vehicle, comprising:

an exhaust pipe for receiving an exhaust gas of an engine of the vehicle;

an exhaust cooling apparatus for cooling the exhaust gas, the exhaust cooling apparatus comprising:

a first fluid conduit;

a variable nozzle opening disposed at one end of the first fluid conduit, the variable nozzle opening being defined by a shape memory alloy extending from the first fluid conduit; and

a second fluid conduit having an inlet end and an outlet end, the variable nozzle opening being disposed in the second fluid conduit proximate to the inlet end of the second fluid conduit such that a fluid inlet opening is disposed about an outer periphery of the variable nozzle opening and an inner surface of the inlet end of the second fluid conduit, the shape memory alloy varying the size of the variable nozzle opening by moving toward or away from a center line of the first fluid conduit in response to a temperature of an exhaust gas flowing through the first fluid conduit, such that the fluid inlet opening increases in area when the variable nozzle moves toward the center line of the first fluid conduit and the fluid inlet opening decreases in area when the variable nozzle moves away from the center line of the first fluid conduit.

10. The exhaust system as in claim 9 , wherein the second fluid conduit further comprises a central portion defining, between the inlet end and the outlet end, a venturi and the variable nozzle opening is defined by a distal end of the shape memory alloy extending from the first fluid conduit, the shape memory alloy being configured such that the shape memory alloy will deflect toward a center line of the first fluid conduit wherein the shape memory alloys decreases the size of the variable nozzle opening and the first fluid conduit is secured to the second fluid conduit by a plurality of stand offs configured to provide flow paths therebetween.

11. The exhaust system as in claim 9 , wherein an exhaust backpressure in the first fluid conduit increases when the shape memory alloy moves toward the center line of the first fluid conduit and the exhaust backpressure in the first fluid conduit decreases when the shape memory alloy moves away from the center line of the first fluid conduit.

12. The exhaust system as in claim 9 , wherein a portion of the inlet end of the second fluid conduit is defined by a second shape memory alloy the second shape memory alloy configured to vary a size of the inlet end of the second fluid conduit by moving toward or away from the center line of the first fluid conduit in response to the temperature of the exhaust gas flowing through the first fluid conduit.

Assignments (12)

Continuity (1)