Hydraulic Fan Assembly for an Engine Ventilation System

• US 20120328455A1
• Filed: 06/22/2011
• Published: 12/27/2012
• Est. Priority Date: 06/22/2011
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Mann, Ryan Chiaki, Patel, Kalpeshbhai G., O'Neill, William N.
• Granted Patent: US 8,939,733 B2
• Time in Patent Office: Days
• US Class Current: 417/375
• CPC Class Codes: F01P 3/12 Arrangements for cooling other engine or machine parts
• CPC Class Codes: F01P 5/04 Pump-driving arrangements
• CPC Class Codes: F04D 25/04 the pump being fluid-driven pumps driven by exhaust gases F02B37/00, F02B39/00; turbochargers F02C6/12
• CPC Class Codes: F04D 29/083 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/102 especially adapted for elastic fluid pumps
• CPC Class Codes: F05D 2260/6022 of leakage having past a seal seals F05D2240/57; glands F05D2240/63

Abstract

A fan for an engine ventilation system includes a housing defining an inlet and an outlet. A hydraulic motor is coupled to the fan housing and includes a motor housing, motor shaft, and shaft seal disposed between the motor housing and the motor shaft. An impeller assembly is disposed in the housing, as well as a stationary baffle that includes a baffle inner edge disposed axially between the impeller assembly and a second wall of the fan housing. A deflector disc is coupled to the impeller assembly and includes a deflector disc outer edge positioned axially rearward of the baffle inner edge. The deflector disc and baffle direct any hydraulic fluid leaking past the shaft seal away from the impeller assembly to a collection chamber.

Claims

1. A centrifugal fan for use with a source of hydraulic fluid, the fan comprising:

a fan housing including a first side wall defining an inlet and a second side wall spaced from the first side wall, the fan housing further defining an outlet;

a hydraulic motor coupled to the second side wall of the fan housing, the hydraulic motor including;

a motor housing;

a hydraulic chamber disposed in the motor housing and fluidly communicating with the source of hydraulic fluid;

a rotatable motor shaft extending along a shaft axis, the motor shaft having an axially rearward end hydraulically coupled to the hydraulic chamber and an axially forward end disposed in the fan housing;

a shaft seal disposed between the motor housing and the motor shaft;

an impeller assembly coupled to the axially forward end of the motor shaft;

a stationary baffle disposed between the first and second side walls of the fan housing, the baffle including a baffle inner edge disposed axially between the impeller assembly and the second wall;

a deflector disc coupled to the impeller assembly, the deflector disc including a deflector disc outer edge positioned axially rearward of the baffle inner edge.

2. The fan of claim 1, in which the fan housing defines an interior chamber, and in which the baffle divides the interior chamber into an impeller chamber in which the impeller assembly is disposed and a collection chamber in which the deflector disc outer edge is disposed.

3. The fan of claim 2, in which the second side wall of the fan housing is configured to define a reservoir in a lower portion of the collection chamber.

4. The fan of claim 1, in which the impeller assembly comprises an impeller plate and a plurality of impeller blades coupled to the impeller plate, each impeller blade having a radial outer periphery relative to the shaft axis, and the baffle inner edge is disposed radially inwardly of the radial outer periphery of each impeller blade.

5. The fan of claim 1, in which the impeller assembly comprises a hub, and in which the deflector disc is coupled to the hub.

6. The fan of claim 1, in which the deflector disc includes a planar deflector disc central portion coupled to the impeller assembly and a non-planar deflector disc outer portion defining the deflector disc outer edge.

7. The fan of claim 6, in which the deflector disc outer portion extends axially rearward from the deflector disc central portion.

8. The fan of claim 7, in which the baffle includes a planar baffle outer portion coupled to the fan housing and a non-planar baffle inner portion defining the baffle inner edge.

9. The fan of claim 7, in which the baffle inner portion extends axially forward from the baffle outer portion.

10. A centrifugal fan for use with a source of hydraulic fluid, the fan comprising:

a fan housing defining an interior chamber, the fan housing including a first side wall defining an inlet and a second side wall spaced from the first side wall, the fan housing further defining an outlet;

a stationary baffle coupled to the fan housing and disposed between the first and second side walls to separate the interior chamber into an impeller chamber adjacent the first side wall and a collection chamber adjacent the second side wall, the baffle including a baffle inner edge;

a hydraulic motor coupled to the second side wall of the fan housing and including;

a motor housing;

a hydraulic chamber disposed in the motor housing and fluidly communicating with the source of hydraulic fluid;

a rotatable motor shaft extending along a shaft axis, the motor shaft having a first end hydraulically coupled to the hydraulic chamber and a second end disposed in the impeller chamber, an outer surface of the motor shaft defining a shaft flow path for hydraulic fluid extending substantially parallel to the shaft axis;

a shaft seal disposed between the motor housing and the motor shaft and in the shaft flow path;

an impeller assembly coupled to second end of the motor shaft, the impeller assembly defining an impeller assembly leak flow path for hydraulic fluid extending substantially perpendicular to the shaft axis from the shaft flow path to a periphery of the impeller assembly;

a deflector disc coupled to the impeller assembly, the deflector disc including a deflector disc outer edge oriented toward the collection chamber, the deflector disc including a deflector disc rear surface defining a deflector flow path for hydraulic fluid extending from an intermediate portion of the impeller assembly leak flow path, thereby to divert leaking hydraulic fluid toward the collection chamber.

11. The fan of claim 10, in which the baffle includes a planar baffle outer portion and a non-planar baffle inner portion defining the baffle inner edge, the baffle inner portion extending toward the first wall of the fan housing.

12. The fan of claim 11, in which the deflector plate includes a planar deflector plate inner portion and a non-planar deflector plate outer portion defining the deflector plate outer edge, the deflector plate outer portion extending toward the second wall of the fan housing.

13. The fan of claim 10, in which the impeller assembly comprises an impeller plate and a plurality of impeller blades coupled to the impeller plate, each impeller blade having a radial outer periphery relative to the shaft axis, and the baffle inner edge is disposed radially inwardly of the radial outer periphery of each impeller blade.

14. The fan of claim 10, in which the impeller assembly comprises a hub, and in which the deflector disc is coupled to the hub.

15. The fan of claim 10, in which the second side wall of the fan housing is configured to define a reservoir in a lower portion of the collection chamber.

16. A centrifugal fan for use with a source of hydraulic fluid, the fan comprising:

a hydraulic motor including a motor housing, a hydraulic chamber disposed in the motor housing and fluidly communicating with the source of hydraulic fluid, a rotatable motor shaft extending along a shaft axis, the motor shaft having an axially rearward end hydraulically coupled to the hydraulic chamber and an axially forward end disposed in the fan housing, and a shaft seal disposed between the motor housing and the motor shaft;

an impeller assembly coupled to the axially forward end of the motor shaft;

a deflector disc coupled to the impeller assembly, the deflector disc including a deflector disc outer edge positioned axially rearward of the baffle inner edge.

17. The fan of claim 16, in which the impeller assembly includes a hub, and in which the deflector disc is coupled to the hub.

18. The fan of claim 16, in which the deflector disc includes a planar deflector disc central portion coupled to the impeller assembly and a non-planar deflector disc outer portion defining the deflector disc outer edge.

19. The fan of claim 18, in which the deflector disc outer portion extends axially rearward from the deflector disc central portion.

20. The fan of claim 16, in which the impeller assembly comprises an impeller plate and a plurality of impeller blades coupled to the impeller plate, each impeller blade having a radial outer periphery relative to the shaft axis, and the deflector plate outer edge is disposed radially inwardly of the radial outer periphery of each impeller blade.