Refrigeration device for container

Patent metadata

Field	Value
Publication number	US-2016377338-A1
Application number	US-201515125745-A
Country	US
Kind code	A1
Filing date	Feb 27, 2015
Priority date	Mar 31, 2014
Publication date	Dec 29, 2016
Grant date	—

Abstract

Disclosed herein is a container refrigeration apparatus ( 10 ) for cooling air in a container ( 11 ). The container refrigeration apparatus ( 10 ) includes: a gas supply device ( 30 ) which produces nitrogen-enriched air having a higher nitrogen concentration than outside air and supplies the nitrogen-enriched air into the container ( 11 ) via a supply passage ( 44 ); an oxygen concentration sensor ( 51 ) which measures an oxygen concentration of the air in the container ( 11 ); and a controller which controls the operation of the gas supply device ( 30 ) so that the oxygen concentration measured by the oxygen concentration sensor ( 51 ) reaches a target concentration. The container refrigeration apparatus ( 10 ) is provided with a measurement passage ( 88 ) which guides part of the nitrogen-enriched air passing through the supply passage ( 44 ) to the oxygen concentration sensor ( 51 ), and an on-off valve ( 82 ) is provided for the measurement passage ( 88 ).

First claim

1 . A container refrigeration apparatus provided in a container, having a refrigerant circuit where a refrigerant circulates to perform a refrigeration cycle, and allowing heat exchange in an evaporator connected to the refrigerant circuit between air in the container and the refrigerant to cool the air, the container refrigeration apparatus comprising:
a gas supply device which produces nitrogen-enriched air having a higher nitrogen concentration than outside air and supplies the nitrogen-enriched air to the interior of the container via a supply passage; an oxygen concentration sensor which measures an oxygen concentration of the air in the container; a controller which controls the operation of the gas supply device so that the oxygen concentration measured by the oxygen concentration sensor reaches a target concentration; a measurement passage which guides part of the nitrogen-enriched air passing through the supply passage to the oxygen concentration sensor so that the oxygen concentration sensor measures the oxygen concentration of the nitrogen-enriched air; and an on-off valve provided for the measurement passage.

2 . The container refrigeration apparatus of claim 1 , wherein
the container houses a fan producing an air flow that passes the evaporator and circulates in the container, and an air passage having one end opened on a blowout side of the fan and the other end opened on a suction side of the fan so that the air in the container flows from the one end to the other end of the air passage as the fan rotates, the oxygen concentration sensor is provided for the air passage to measure the oxygen concentration of the air passing through the air passage, the measurement passage is comprised of a branch pipe which connects the supply passage and the air passage, the branch pipe diverging, and guiding to the air passage, part of the nitrogen-enriched air passing through the supply passage, and the controller is configured to perform, while the gas supply device is in operation and a rotation of the fan is stopped, a supply air measurement operation in which the on-off valve is opened and the oxygen concentration sensor is allowed to measure the oxygen concentration of the nitrogen-enriched air.

3 . The container refrigeration apparatus of claim 1 , wherein
a calibration gas introduction mechanism which introduces a calibration gas for use in calibration of the oxygen concentration sensor into the measurement passage is provided for the measurement passage to be closer to the oxygen concentration sensor than the on-off valve.

4 . The container refrigeration apparatus of claim 2 , wherein
the evaporator is provided on the blowout side of the fan, the container refrigeration apparatus further comprises a unit controller which performs a cooling operation in which the fan is rotated and the refrigerant is circulated in the refrigerant circuit so that the air in the container is cooled in the evaporator through heat exchange with the refrigerant, and a defrosting operation in which the evaporator is defrosted by heating the evaporator with the rotation of the fan stopped, and the controller is configured to perform, while the unit controller is performing the defrosting operation, the supply air measurement operation in which the on-off valve is opened and the oxygen concentration sensor is allowed to measure the oxygen concentration of the nitrogen-enriched air.

5 . The container refrigeration apparatus of claim 2 , wherein
a calibration gas introduction mechanism which introduces a calibration gas for use in calibration of the oxygen concentration sensor into the measurement passage is provided for the measurement passage to be closer to the oxygen concentration sensor than the on-off valve.

Assignees

• Daikin Ind Ltd

Inventors

• Tanaka Naohiro
• Kamei Noritaka

Classifications

• A23B2/708

  in a controlled atmosphere, e.g. partial vacuum, comprising only CO2, N2, O2 or H2O · CPC title

• A23B2/80

  Freezing; Subsequent thawing; Cooling · CPC title

• A23B2/001

  Details of apparatus, e.g. pressure feed valves or for transport, or loading or unloading manipulation · CPC title

• F25D11/003

  Transport containers · CPC title

• A23L3/36

  Human Necessities · mapped topic