Lubrication system for waste heat recovery gear box

• US 9,932,889 B2
• Filed: 10/02/2016
• Issued: 04/03/2018
• Est. Priority Date: 10/01/2015
• Status: Active Grant

• Current Assignee: Cummins Incorporated
• Original Assignee: Cummins Incorporated
• Inventors: Bagayatkar, Nimish
• Primary Examiner(s): NGUYEN, HOANG M
• Application Number:
  US15/546,082
• Publication Number:
  US 20180030885A1
• Time in Patent Office: 548 Days
• Field of Search: 60614, 60616, 60618
• CPC Class Codes: F01K 23/065 the combustion taking place in an internal combustion piston engine, e.g. a diesel engine
• CPC Class Codes: F01M 5/002 Cooling
• CPC Class Codes: F02B 39/085 the fluid drive using expansion of fluids other than exhaust gases, e.g. a Rankine cycle
• CPC Class Codes: F16H 57/0434 relating to lubrication supply, e.g. pumps arrangement of pumps F16H57/0441; Pressure control grooves with pumping effect for supplying lubricant F16H57/0428; generation and variation of line pressure for transmission control F16H61/0021
• CPC Class Codes: F16H 57/0436 Pumps
• CPC Class Codes: F16H 57/0441 Arrangements of pumps
• CPC Class Codes: F16H 57/0445 for supply of different gearbox casings or sections
• CPC Class Codes: F16N 13/10 with mechanical drive F16N13/18 takes precedence
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A lubrication system and method for an engine are provided. In some embodiments, the lubrication method comprises driving a lube pump with a gearbox in a power drive housing, the gearbox including an expander shaft of an expander of a waste heat recovery system; suctioning lubrication fluid, with the lube pump, from a lube sump in the power drive housing; lubricating, with the lubrication fluid, an expander shaft bearing supporting the expander; and after lubricating the expander shaft bearing, transferring the lubrication fluid to the lube sump.waste heat recovery power drive and lubrication system therefor.

Claims

1. A lubrication method comprising:

driving a lube pump with a gearbox, the gearbox including an expander shaft of an expander of a waste heat recovery system;

suctioning lubrication fluid, with the lube pump, from a lube sump in a power drive housing;

lubricating, with the lubrication fluid, an expander shaft bearing supporting the expander; and

after lubricating the expander shaft bearing, transferring the lubrication fluid to the lube sump.

2. A method as in claim 1, further comprising:

pumping a working fluid through a cooling circuit in the power drive housing; and

transferring heat from the lubrication fluid to the working fluid through the power drive housing to cool the lubrication fluid.

3. A method as in claim 2, wherein the lubrication fluid is miscible with the working fluid.

4. A method as in claim 1, further comprising driving a feed pump to circulate a working fluid through the power drive housing to cool the power drive housing.

5. A method as in claim 4, wherein driving a feed pump comprises driving a first gear train of the gearbox with the expander shaft of the expander.

6. A method as in claim 5, wherein the first gear train comprises a bull gear mounted on the output shaft, wherein the cooling pump is driven by the output shaft.

7. A method as in claim 5, further comprising driving a second gear train of the gearbox with the first gear train to transfer power to a crankshaft of an internal combustion engine.

8. A method as in claim 1, further comprising transferring power from the expander of the waste heat recovery system to a crankshaft of an internal combustion engine with the gearbox in the power drive housing.

9. A method as in claim 8, wherein transferring power comprises driving a second gear train of the gearbox with an output shaft driven by the expander shaft.

10. A method as in claim 1, wherein suctioning lubrication fluid comprises transferring the lubrication fluid from the lube sump through a lube suction rifle located on an enclosure cover of the power drive housing.

11. A method as in claim 10, further comprising transferring the lubrication fluid from the enclosure cover to the expander shaft bearing through a lube filter.

12. A method as in claim 1, wherein the lubricating fluid flows through a lubrication circuit that is independent of a lubrication circuit of an internal combustion system driving the waste heat recovery system.

13. A lubrication system comprising:

a power drive housing including an enclosure cover mounted on a power drive housing body;

a lube pump enclosed by the power drive housing;

a first gear train adapted to be driven by an expander of a waste heat recovery system having an expander shaft;

an output shaft supporting the lube pump and driven by the first gear train; and

a lube sump, wherein the lube pump is configured to suction a lubrication fluid from the lube sump to lubricate the first gear train.

14. The lubrication system of claim 13, further comprising an expander bearing supporting the expander shaft, and a lube discharge rifle and a lube return slot on the power drive housing, wherein the lube pump is configured to discharge the lubrication fluid through the lube discharge rifle to lubricate the expander bearing and return the lubrication fluid to the lube sump.

15. The lubrication system of claim 14, wherein the lube discharge rifle is positioned on the enclosure cover of the power drive housing.

16. The lubrication system of claim 13, wherein the lubricating fluid flows through a lubrication circuit that is independent of a lubrication circuit of an internal combustion system driving the waste heat recovery system.