Accumulator for charge management

Patent metadata

Field	Value
Publication number	US-10619900-B2
Application number	US-201715644211-A
Country	US
Kind code	B2
Filing date	Jul 7, 2017
Priority date	Jul 7, 2016
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

Embodiments of an accumulator for charge management are described. A fluid compression system, comprising an accumulator fluidly connected to an evaporator via a spillover port. The spillover port directs working fluid received from the evaporator to be collected and stored in the accumulator, where the stored working fluid is stored and released from the accumulator in response to an operating condition of the evaporator.

First claim

The invention claimed is:

1. A fluid compression system, comprising:
a compressor;
a condenser, an expansion device, and an evaporator fluidly connected to the compressor;
an accumulator fluidly connected to the evaporator via a spillover port, the spillover port directs working fluid received from the evaporator to be collected and stored in the accumulator;
a first conduit fluidly connected to the accumulator and the compressor, the first conduit configured to direct lubricant from the accumulator to the compressor;
a fill and drain valve fluidly connected to the accumulator; and
a second conduit fluidly connected to the accumulator and at a location disposed fluidly between an outlet of the condenser and an inlet of the expansion device, the fill and drain valve disposed in the second conduit, the fill and drain valve configured to release working fluid stored in the accumulator to the second conduit, wherein actuation of the fill and drain valve is in response to a start-up operating condition relative to the evaporator,
wherein the working fluid is stored and released from the accumulator in response to an operating condition of the evaporator.

2. The system of claim 1 , wherein the operating condition is among a plurality of operating conditions, and each operating condition among the plurality of operating conditions is relative to the evaporator and corresponds to a working fluid level in the accumulator.

3. The system of claim 2 , wherein the plurality of operating conditions include:
a full load operating condition that corresponds to a full load working fluid level in the accumulator;
a partial load operating condition that corresponds to a partial working fluid level in the accumulator;
a shut-down operating condition that corresponds to a working fluid loss level in the accumulator; and
a start-up operating condition that corresponds to a start-up working fluid level in the accumulator.

4. The system of claim 1 , further comprising an indicator, the indicator configured to:
detect a working fluid level in the accumulator, wherein the detected working fluid level in the accumulator corresponds to an amount of charge and particular operating condition associated with the evaporator; and
identify, via the detected level of working fluid the accumulator, a partial load operating condition at which the fluid compression system operates.

5. The system of claim 1 , further comprising a controller to initiate a shut-down operating condition when an indicator detects a working fluid loss level stored in the accumulator for a predetermined period of time.

6. The system of claim 1 , further comprising an indicator located at least partially within the accumulator, wherein the indicator is configured to:
detect a working fluid level in the accumulator, the working fluid level corresponds to a stored charge amount and the operating condition relevant to the evaporator; and
provide an indication to a controller of the fluid compression system of a detected working fluid loss level that corresponds to a charge loss operating condition relative to the evaporator.

7. The system of claim 1 , wherein the operating condition of the evaporator is a transition operating condition, and
the transition operating condition corresponds to a transition working fluid level of the accumulator, and wherein the transition operating condition does not initiate a shut-down operating condition.

8. The system of claim 7 , wherein the transition operating condition indicates a partial working fluid level in the evaporator for a predetermined time to prevent a false charge loss indication.

9. The system of claim 1 , wherein the accumulator is external to the evaporator, and a working fluid spill-over rate from the evaporator to the accumulator is directly correlated.

10. A cooling system, comprising:
a compressor;
a condenser fluidly connected to the compressor;
an evaporator fluidly connected to the compressor;
an expansion device fluidly connected to the evaporator and the condenser;
an accumulator fluidly connected to the evaporator;
a fill and drain valve fluidly connected to the accumulator, the fill and drain valve arranged to release working fluid stored in the accumulator to pass from the accumulator to the expansion device and evaporator based on an operating condition of the evaporator;
a first conduit fluidly connected to the accumulator and the compressor, the first conduit configured to direct lubricant from the accumulator to the compressor;
a second conduit fluidly connected to the accumulator and at a location between an outlet of the condenser and an inlet of the expansion device, the fill and drain valve disposed in the second conduit.

11. The cooling system of claim 10 , wherein working fluid is released from the accumulator via the fill and drain valve in response to a start-up operating condition relative to the evaporator.

12. The cooling system of claim 10 , wherein the fill and drain valve is opened and an expansion valve of the expansion device is closed in response to a shut-down operating condition to isolate a vaporization of the working fluid in the evaporator.

13. The cooling system of claim 12 , wherein the fill and drain valve is opened and the expansion valve is opened in response to a start-up operating condition relative to the evaporator, wherein the accumulator provides stored working fluid to the evaporator.

14. The cooling system of claim 10 , further comprising an indicator located at least partially within the accumulator, wherein the indicator is a level sensor.

15. The cooling system of claim 14 , wherein the indicator detects a working fluid level within the accumulator, the working fluid level correlates to the operating condition of the evaporator.

16. The cooling system of claim 14 , wherein the indicator is configured to provide an indication of a working fluid loss charge level to a controller that correlates to a shut-down operating condition in the evaporator.

17. A method of controlling a fluid compression system, comprising:
detecting, via an indicator, a working fluid level stored in an accumulator;
correlating the working fluid level to an operating condition among a plurality of operating conditions relative to an evaporator;
storing, in the accumulator, an amount of charge provided from the evaporator in response to the operating condition, wherein the working fluid level increases or decreases depending upon the operating condition; and
actuating a fill and drain valve fluidly connected to the accumulator, the fill and drain valve fluidly disposed at a location between an outlet of a condenser and an inlet of an expansion device based on the operating condition of the evaporator.

18. The method of claim 17 , further comprising initiating, via a controller, a shut-down operating condition relative to the evaporator in response to the working fluid level being less than a working fluid threshold level, wherein charge from the evaporator at least substantially fills the accumulator.

Assignees

• Trane Int Inc

Inventors

• Sibik Lee L

Classifications

• F25B45/00 Primary

  Arrangements for charging or discharging refrigerant · CPC title

• F25B2700/04

  Refrigerant level · CPC title

• F25B49/02

  for compression type machines, plants or systems · CPC title

• F25B2345/003

  Control issues for charging or collecting refrigerant to or from a cycle · CPC title

• F25D1/00

  Devices using naturally cold air or cold water · CPC title