Granted Patent B2

US 9,518,592 · App. 14/005,884 · Granted Dec 13, 2016

Abstract

Claims (21)

1. A pump assembly for use in a selective catalytic reduction system, the pump assembly comprising:

a pump housing having a body portion and a nozzle portion extending from the body portion to define a pump axis (A);

a jacket including a cavity for receiving the pump housing;

first and second ports for cooling fluid;

a flow guide disposed between the jacket and the pump housing;

a first compartment for cooling fluid defined in part by the flow guide and in part by the pump housing, the first compartment being in fluid communication with the first port; and

a second compartment for cooling fluid defined in part by the flow guide and in part by the jacket;

wherein the first compartment is in fluid communication with the second port by way of the second compartment.

2. A pump assembly according to claim 1 , arranged such that, in use, cooling fluid flows through the first compartment in a first direction generally parallel to the pump axis (A), and through the second compartment in a second direction generally opposite to the first direction.

3. A pump assembly according to claim 1 , further comprising a third compartment for cooling fluid defined in part by the flow guide and in part by the jacket; and wherein the first compartment is in fluid communication with the first port by way of the third compartment.

4. A pump assembly according to claim 3 , arranged such that, in use, cooling fluid flows through the first compartment in a first direction generally parallel to the pump axis (A), and through the second and third compartments in a second direction generally opposite to the first direction.

5. A pump assembly according to claim 1 , wherein the first compartment extends along the nozzle portion of the pump housing.

6. A pump assembly according to claim 5 , wherein the flow guide includes a generally tubular portion arranged concentrically around the nozzle portion of the pump housing, and wherein the second compartment is defined in part by the generally tubular portion.

7. A pump assembly according to claim 1 , wherein the flow guide includes an enlarged-diameter portion arranged concentrically around the body portion of the pump housing.

8. A pump assembly according to claim 1 , wherein the flow guide comprises support means that cooperate with the jacket to support the flow guide in the cavity.

9. A pump assembly according to claim 8 , wherein the support means comprises an annular flange provided on the flow guide.

10. A pump assembly according to claim 8 , wherein the jacket comprises a first jacket part and a second jacket part that seals against the first jacket part at a joint in the jacket, and wherein the support means cooperates with the jacket at the joint.

11. A pump assembly according to claim 1 , wherein the jacket comprises a generally tubular portion arranged concentrically around the nozzle portion of the pump housing.

12. A pump assembly according to claim 11 , wherein the generally tubular portion of the jacket comprises retaining means for retaining an outlet end of the nozzle portion of the pump housing.

13. A pump assembly according to claim 1 , wherein at least a part of the cavity has a circular cross-section, and wherein at least one of the first and second ports is arranged substantially tangentially with respect to the cavity.

14. A pump assembly according to claim 1 , wherein the first and second ports are adjacent to one another.

Assignments (8)