Preload system for bearings in a waterjet propulsion apparatus

• US 7,318,759 B2
• Filed: 06/07/2006
• Issued: 01/15/2008
• Est. Priority Date: 06/07/2006
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Dennis, Richard H., Aitchison, Jeffrey J., Selder, Albert G., Harper, William B., Kumar, Arun, Bristol, Brent L.
• Primary Examiner(s): Olson; Lars A.
• Application Number:
  US11/448,442
• Publication Number:
  US 20070287339A1
• Time in Patent Office: 587 Days
• Field of Search: 440/38, 384/493, 384/499, 384/500, 384/501, 384/551, 384/557, 602/21, 602/22
• US Class Current: 440/38
• CPC Class Codes: F16C 19/364 with tapered rollers, i.e. rollers having essentially the shape of a truncated cone
• CPC Class Codes: F16C 19/525 related to temperature and heat, e.g. insulation
• CPC Class Codes: F16C 19/548 in O-arrangement
• CPC Class Codes: F16C 25/08 self-adjusting
• CPC Class Codes: F16C 35/042 Housings for rolling element bearings for rotary movement
• CPC Class Codes: F16C 35/077 between housing and outer race ring

Abstract

A preload system for bearings in a waterjet propulsion apparatus, the apparatus including a water intake section and a pumping unit including a bearing cartridge. The bearing cartridge is designed such that during operation a preload system provides tailoring between radial and axial thermal growths of a plurality of bearing components that comprise the bearing cartridge and such that an initial ambient temperature preload condition can be maintained or reduced during normal water mode operation conditions. The preload system includes a plurality of spacers that when positioned relative to the bearing components of the bearing cartridge prevent relative motion between the bearing components during land mode operation and maintain or reduce the initial ambient room temperature preload condition during normal water mode operation.

Claims

1. A waterjet propulsion apparatus comprising:

a housing having at least a fluid intake section; and

a pumping unit disposed within the housing and in fluidic communication with the water intake section, the pumping unit comprising;

a rotor comprising a plurality of rotor blades coupled to a rotor hub;

a bearing cartridge coupled to the rotor and having an initial ambient temperature preload condition, the bearing cartridge comprised of a plurality of bearing components; and

a stator having a fluid inlet disposed adjacent the rotor, and a fluid outlet disposed downstream of the fluid inlet,

wherein the bearing cartridge further includes a thermally insensitive solid bearing preload system comprising a bearing support system that is preloaded using a plurality of spacers comprising a retainer clamp spacer positioned to maintain a distance between the plurality of bearing components, a shaft spacer positioned to maintain a distance between the plurality of bearing components, and a clamping nut positioned a distance from one of the plurality of bearing components, the plurality of spacers configured to prevent relative motion between the plurality of bearing components that comprise the bearing cartridge and provide adjustment of the initial ambient temperature preload condition.

2. The apparatus of claim 1 wherein the bearing cartridge comprises a bearing cavity, the plurality of bearing components are formed within the bearing cavity and comprise a bearing assembly having at least a plurality of roller bearing elements supported by a plurality of inner races, outer races and a retainer.

3. The apparatus of claim 1 wherein the plurality of bearing components comprise a first roller bearing element and a second roller bearing element positioned back-to-back.

4. The apparatus of claim 3 wherein the first and second roller bearing elements are tapered roller bearings.

5. The apparatus of claim 3 wherein the retainer clamp spacer is positioned between the first and second roller bearing elements and the shaft spacer is positioned to extend between the first and second roller bearing elements and the clamping nut is positioned a distance from one of the first roller bearing or the second roller bearing element.

6. The apparatus of claim 1 wherein the retainer clamp spacer is formed integral with the retainer.

7. The apparatus of claim 1 wherein the retainer clamp spacer and the shaft spacer are each comprised of a material having coefficients of thermal expansion (CTE) such that the ambient temperature preload condition at the start of apparatus operation can be controlled during a structural thermal heating of the apparatus under normal water mode operation.

8. The apparatus of claim 1 wherein at least a portion of the plurality of bearing components are formed of a material having a coefficient of thermal expansion chosen to tailor changes in the preload of the thermally insensitive solid bearing preload system.

9. A pumping unit for a waterjet propulsion apparatus comprising:

a rotor comprising a plurality of rotor blades coupled to a rotor hub and having a bearing cartridge coupled to the rotor, the bearing cartridge having an initial ambient temperature preload condition and comprised of a plurality of bearing components; and

a stator having a fluid inlet disposed adjacent to and downstream of the rotor, and a fluid outlet disposed downstream of the stator,

wherein the bearing cartridge further comprises a bearing cavity, the plurality of bearing components are housed within a bearing cavity and comprise a bearing assembly having at least a plurality of roller bearing elements supported by a plurality of races, a bearing shaft, an outer ring, and a retainer, the bearing cartridge further including a thermally insensitive solid bearing preload system comprising a bearing support system that is preloaded using a retainer clamp spacer positioned to maintain a distance between the plurality of roller bearing elements and a shaft spacer positioned to extend between the plurality of roller bearing elements to prevent relative motion between the plurality of roller bearing elements, the plurality of races, the outer ring, and the retainer and provide adjustment of the initial ambient temperature preload condition in response to radial and axial thermal growths of the plurality of bearing components.

10. The pumping unit of claim 9 wherein the plurality of roller bearing elements comprise a first roller bearing element spaced apart from a second roller bearing element, each of the first and second roller bearing elements having a front face, wherein the first and second roller bearings elements are positioned back-to-back.

11. The pumping unit of claim 10 wherein the first and second roller bearing elements are tapered roller bearing elements.

12. The pumping unit of claim 10 wherein the retainer clamp spacer is positioned between the first and second roller bearing elements and the shaft spacer is positioned to extend between the first and second roller bearing elements and a clamping nut is positioned a distance from the front face of one of the plurality of roller bearing elements.

13. The pumping unit of claim 9 wherein the retainer clamp spacer is formed integral with the retainer.

14. The pumping unit of claim 9 wherein the retainer clamp spacer and the shaft spacer each have a length tailored such that the ambient temperature preload condition at the start of the apparatus operation can be controlled during normal operation.

15. The pumping unit of claim 9 wherein the retainer clamp spacer and the shaft spacer are each comprised of a material having a coefficient of thermal expansion (CTE) such that the ambient temperature preload condition at the start of the apparatus operation can be controlled during normal operation.

16. A pumping unit for a waterjet propulsion apparatus comprising:

a rotor comprising a plurality of rotor blades coupled to a rotor hub;

a stator having a fluid inlet disposed adjacent the rotor, and a fluid outlet disposed downstream of the fluid inlet; and

a bearing cartridge coupled to the rotor and having an initial ambient temperature preload condition, the bearing cartridge comprising a bearing cavity having a plurality of bearing components housed within the bearing cavity, the plurality of bearing components comprising a bearing assembly having at least a plurality of roller bearing elements supported by a plurality of races, an outer ring, and a retainer,

wherein the bearing cartridge further includes a thermally insensitive solid bearing preload system comprising a retainer clamp spacer positioned to maintain a distance between the plurality of roller bearing elements and a shaft spacer positioned to maintain a distance between a clamping nut and the plurality of roller bearing elements, the retainer clamp spacer and the shaft spacer preventing relative motion between the plurality of roller bearing elements, the plurality of races, and the outer ring in the bearing assembly and providing adjustment of the initial ambient temperature preload condition in response to radial and axial thermal growths of the plurality of roller bearing elements, the plurality of races, the outer ring, the retainer, the retainer clamp spacer and the shaft spacer.

17. The pumping unit of claim 16 wherein the plurality of roller bearing elements comprise a first tapered roller bearing and a second tapered roller bearing positioned back-to-back within the bearing cavity.

18. The pumping unit of claim 16 wherein the retainer clamp spacer is formed integral with the retainer.

19. The pumping unit of claim 16 wherein the retainer clamp spacer and the shaft spacer each have a length tailored such that the ambient temperature preload condition at the start of the apparatus operation can be controlled during normal operation.

20. The pumping unit of claim 16 wherein the retainer clamp spacer and the shaft spacer are each comprised of a material having a coefficient of thermal expansion (CTE) such that the ambient temperature preload condition at the start of the apparatus operation can be controlled during normal operation.