Detection of CO 2 leakage in a container

• US 8,610,588 B2
• Filed: 01/17/2008
• Issued: 12/17/2013
• Est. Priority Date: 01/17/2008
• Status: Active Grant

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Carrier Corporation (Carrier Global Corporation)
• Inventors: Asprovski, Zvonko, Duraisamy, Suresh
• Primary Examiner(s): Bugg, George
• Assistant Examiner(s): Labbees, Edny
• Application Number:
  US12/745,757
• Publication Number:
  US 20100271221A1
• Time in Patent Office: 2,161 Days
• Field of Search: 340/632, 73/232, 73/351.4, 73/351.7, 623/71, 624/40, 622/46, 624/52, 621/65, 621/32, 621/26, 621/25, 621/29
• US Class Current: 340/632
• CPC Class Codes: F25B 2309/061 with cycle highest pressure above the supercritical pressure
• CPC Class Codes: F25B 49/005 of safety devices F25B49/02 and F25B49/04 take precedence
• CPC Class Codes: G01M 3/228 for radiators

Abstract

A refrigerated container having a refrigeration system using CO₂ as the refrigerant, includes a sensing and warning system for sensing the CO₂ concentration in the container and responsively displaying the sensed condition in a display module so that an operator will be aware of excess levels of concentration which might present a hazardous condition and therefore should not enter the container until the condition is alleviated.

Claims

1. A refrigerated container system comprising:

a refrigeration system including a refrigeration circuit having in serial flow relationship a compressor for compressing CO₂ vapor as a refrigerant, a heat rejecting heat exchanger, an expansion device and a heat absorbing heat exchanger;

a refrigerated cargo container having said heat absorbing heat exchanger disposed in heat exchange relationship with a flow of return air from said refrigerated cargo container;

a CO₂ sensor located within said flow of return air for sensing when a level of CO₂ concentration therein reaches a predetermined higher level and for generating a signal representative thereof said CO₂ sensor being in a position to sample the flow of return air entering the refrigeration system to the CO₂ concentration therein;

and a control for receiving said representative signal and responsively generating a visual display of the sensed condition.

2. The refrigerated container system as set forth in claim 1 wherein said CO₂ sensor is disposed within said refrigerant system.

9. The refrigerated container system as set forth in claim 1 wherein said refrigerated cargo container comprises a truck-trailer.

10. The refrigerated container system as set forth in claim 1 wherein said refrigerated cargo container comprises a container for land and sea service.

3. A method of reducing the risk of an operator entering a cargo container which may contain CO₂ leakage from an associated vapor compression refrigeration system for cooling the cargo container comprising the steps of:

sensing the concentration of CO₂ in a flow of return air entering the refrigeration system from the cargo container and generating a representative signal thereof;

providing a controller for receiving said representative signal and for providing an appropriate display signal in response thereto; and

providing a display console for receiving said display signal and generating an appropriate visual display thereof.

4. The method as set forth in claim 3 wherein said display indicates that either a hazardous condition is present in the container or that no hazardous condition is present in the cargo container.

5. The method as set forth in claim 3 and including the step of comparing said representative signal with a predetermined threshold, and with the display providing an indication of whether that threshold has been exceeded.

6. The method as set forth in claim 5 wherein said predetermined threshold is in the range of 1% and 8%.

7. The method as set forth in claim 6 wherein said threshold is about 3%.

8. The method as set forth in claim 3 wherein said display console generates a visual display to alert a person outside the cargo container of a potential hazardous atmosphere inside the cargo container.