Refrigerated trailer and method for same

Abstract

The present invention relates to a refrigerated trailer for storage and transport of refrigerated products such as perishable food. The refrigerated trailer comprises an insulated box with a side door; a refrigeration unit for cooling air inside the insulated box, the refrigeration unit including an engine for supplying mechanical power to the refrigeration unit, batteries, and a compressor operatively coupled to the engine; an inverter electrically coupled to the batteries for supplying AC power; and an air curtain unit located above the side door, the air curtain unit including fans operating on AC power from the inverter, wherein the fans blow internal air downwardly over the door opening to limit air exchange between the insulated box and the outdoors.

1 . A refrigerated trailer comprising:
 an insulated box having a door opening and a side door associated with the door opening;   a refrigeration unit for cooling air inside the insulated box, the refrigeration unit including an engine for supplying mechanical power to the refrigeration unit, batteries, and a compressor operatively coupled to the engine;   an inverter electrically coupled to the batteries for supplying AC power; and   an air curtain unit located above the side door, the air curtain unit including fans operating on AC power from the inverter;   wherein the fans blow internal air downwardly over the door opening to limit air exchange between the insulated box and the outdoors.   
   
   
       2 . The refrigerated trailer of  claim 1  further comprising a thermostat connected to a sensor that senses ambient temperature, wherein the fans of the air curtain unit are disabled if the ambient temperature is below a preset temperature. 
   
   
       3 . The refrigerated trailer of  claim 1  wherein the inverter is located outside the insulated box near the refrigeration unit. 
   
   
       4 . The refrigerated trailer of  claim 1  wherein the insulated box contains multiple compartments, each compartment separated from an adjacent compartment by an interior wall. 
   
   
       5 . The refrigerated trailer of  claim 4  wherein the interior wall is movable, whereby sizes of the compartments are adjustable. 
   
   
       6 . The refrigerated trailer of  claim 4  wherein the insulated box includes a freezer compartment and a cooler compartment, each one of the freezer compartments and cooler compartments having a side door. 
   
   
       7 . The refrigerated trailer of  claim 6  wherein the freezer compartment is at the front of the insulated box and the cooler compartment is rearward of the freezer compartment. 
   
   
       8 . The refrigerated trailer of  claim 7  wherein each compartment includes a thermostat connected to a sensor that senses ambient temperature and each compartment includes an air curtain unit whereby the fans of the air curtain unit are disabled if the ambient temperature is below a preset temperature. 
   
   
       9 . The refrigerated trailer of  claim 7  wherein one compartment includes a thermostat connected to a sensor that senses ambient temperature and one compartment includes an air curtain unit whereby the fans of the air curtain unit are disabled if the ambient temperature is below a preset temperature. 
   
   
       10 . The refrigerated trailer of  claim 6  wherein the insulated box includes a third compartment rearward of the cooler compartment, the third compartment having a side door. 
   
   
       11 . The refrigerated trailer of  claim 10  wherein the freezer compartment is at the front of the insulated box, the third compartment is at the back of the insulated box, and the cooler compartment is between the freezer compartment and the third compartment. 
   
   
       12 . The refrigerated trailer of  claim 1  wherein the refrigerated trailer contains three side doors on the left side of the insulated box and one side door on the right side of the insulated box. 
   
   
       13 . The refrigerated trailer of  claim 1  wherein the fans of the air curtain unit are disabled when the side door is closed. 
   
   
       14 . The refrigerated trailer of  claim 1  wherein the air curtain unit is located inside the insulated box. 
   
   
       15 . A method of maintaining temperature and humidity inside a refrigerated trailer, comprising the steps of:
 providing an insulated box having a door opening on a side of the insulated box and a side door;   refrigerating air inside the insulated box, including operating a refrigeration unit that includes an engine, batteries, and a compressor operatively coupled to the engine;   inverting DC current from the batteries to deliver AC power to fans of an air curtain unit located above the side door;   blowing internal air via the fans downwardly from above an opening in the side door to limit air exchange between the enclosure and the outdoors;   sensing an outdoor temperature; and   disabling the fans if the outdoor temperature is below a preset temperature.   
   
   
       16 . The method of  claim 15  further comprising disabling the fans of the air curtain unit when the side door is closed.