Passive oil level limiter

Patent metadata

Field	Value
Publication number	US-9541312-B2
Application number	US-99128808-A
Country	US
Kind code	B2
Filing date	May 7, 2008
Priority date	May 7, 2008
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A vapor expansion/compression system having an oil sump for lubrication of the turbine/compressor bearings includes an oil and/or vapor vent line leading from a strategic location in the oil sump to the condenser such that the oil level in the sump is limited to the predetermined level, and any excess oil is pumped from the sump to thereby prevent the oil level from reaching a level at which bearings failure could be caused due to a high oil level.

First claim

We claim:

1. A method of preventing the lubricant level in a turbine/compressor sump of a vapor expansion/compressor system from reaching a high level sufficient to cause a mechanical failure in the turbine/compressor rotating equipment including bearings, comprising the steps of:
providing a pumped path out of the sump so that the lubricant can be removed from the oil sump at a pre-determined threshold level
providing a passive or active response that causes oil removal through this path when the lubricant level reaches the pre-determined level in the sump
determining when the level of lubricant in the sump reaches a predetermined threshold level which is above a minimum required level and below the high level;
responsively causing lubricant to be pumped out of the sump so that the lubricant level does not substantially exceed said predetermined threshold level; and
said lubricant is pumped out of the sump and into a condenser.

2. The method as set forth in claim 1 wherein said vapor expansion/compression system includes an oil vent tube extending from said sump to said condenser, with said oil vent extending into said sump with an open end disposed at said acceptable level, and with the pressure in said sump being greater than in said condenser such that when the oil level in the sump is above the oil vent open end, it will be caused to flow through the oil vent to the condenser.

3. The method as set forth in claim 1 wherein said vapor expansion/compression system includes a pump and a level sensor with said pump being in fluid communication between said sump and said condenser, and said level sensor being operative to sense the lubricant level in said sump and further wherein said level sensor responsively causes said pump to cause the oil to be pumped out of the sump.

4. The method as set forth in claim 1 wherein said vapor expansion/compression system includes an educator and a dip tube, with said educator being fluidly interconnected between said oil sump and said condenser and said dip tube being disposed in said oil sump at said acceptable level, such that when the oil level is above said dip tube, said educator causes the oil to be pumped out of the sump.

5. The method as set forth in claim 1 wherein said oil/vapor vent line has an open end disposed at said predetermined level within the sump and further wherein the pressure in the sump is greater than the pressure in the condenser so as to cause the flow of oil and/or working fluid from the sump to the condenser.

6. A closed loop vapor compression or expansion system of the type having an oil separator, a condenser and a compressor or turbine with bearings to be lubricated from an oil sump located below the bearings, comprising:
a pump for causing oil to flow from the oil separator to the oil sump;
an oil/vapor vent line fluidly communicating between the sump and the condenser; and
a fluid flow causing system for causing oil to flow from the sump to the condenser by way of said oil/vapor vent line when a level of oil in the sump is above a predetermined level.

7. The closed loop vapor compression or expansion system as set forth in claim 6 , wherein said oil/vapor vent line has an open end disposed at said predetermined level within the sump and further wherein the pressure in the sump is greater than the pressure in the condenser so as to cause the flow of oil from the sump to the condenser.

8. The closed loop vapor compression or expansion system as set forth in claim 6 and including a sensor for determining the level of oil in the sump and a pump for responsively pumping oil from the sump to the condenser when the oil level is above said predetermined level.

9. The closed loop vapor compression or expansion system as set forth in claim 6 wherein said fluid flow causing means comprises an educator.

Assignees

• Woolley Lance D
• Matteson Peter S
• United Technologies Corp

Inventors

• Woolley Lance D
• Matteson Peter S

Classifications

• F01D25/20

  using lubrication pumps · CPC title

• F25B31/004 Primary

  oil recirculating arrangements · CPC title

• F25B2700/03

  Oil level · CPC title