Thermoelectric refrigerator with evaporating/condensing heat exchanger

A method for increasing the heat transfer efficiency of a thermoelectric refrigerator having thermoelectric heat transfer system including a thermoelectric device with a plurality of thermoelectric elements disposed between a first thermally conductive plate and a second thermally conductive plate with the thermoelectric elements electrically coupled in series with respect to each other and thermally coupled in parallel with respect to the first and second thermally conductive plates, comprising the steps of:

• thermally coupling the first thermally conductive plate with a heat sink;
• placing the heat sink within the thermoelectric refrigerator with the second chamber having a plurality of hollow tubes;
• forming a heat exchanger having a first chamber and a second chamber;
• forming a fluid flow path between the first chamber and the second chamber;
• forming a first evaporating surface as a part of the first chamber and forming a second condensing surface as a part of the second chamber;
• placing a working fluid within the heat exchanger and sealing the heat exchanger to prevent undesired escape of the working fluid;
• thermally coupling the first evaporating surface with the second thermally conductive plate;
• providing electrical power to the thermoelectric elements to transfer heat energy from the heat sink and the first thermally conductive plate to the second thermally conductive plate;
• transferring heat energy from the second thermally conductive plate to the first evaporating surface to convert the working fluid from its liquid phase to its vapor phase;
• communicating the working fluid in its vapor phase from the first chamber to the second chamber through the fluid flow path;
• condensing the working fluid in its vapor phase on the second condensing surface in the second chamber;
• and
• returning the condensed working fluid to the first chamber through the fluid flow path.

A thermoelectric refrigerator defined in part by an enclosed structure having five walls and an opening to an interior of the enclosed structure and a door assembly mounted on the opening for selectively controlling access to the interior of the enclosed structure and a thermoelectric heat transfer system comprising:

• a thermoelectric device with first and second thermally conductive flat plates lying in generally parallel planes;
• a heat exchanger with a first evaporating section and a second condensing section, the first evaporating section coupled to the second thermally conductive plate;
• the second condensing section disposed above and connected to the first evaporating section by a fluid flow path extending therebetween;
• the evaporating section further comprising a first portion and a second portion coupled together to form a fluid tight chamber;
• the first portion having a reduced fluid volume with respect to the second portion;
• the second portion coupled to and disposed above the first portion;
• the second portion having a fluid volume sized larger than the first portion to accommodate communication of working fluid in its vapor phase with the fluid flow path;
• and
• a heat sink coupled to the first thermally conductive plate of the thermoelectric device.

A thermoelectric refrigerator defined in part by an enclosed structure and a thermoelectric heat transfer system for controlling the temperature within the enclosed structure, comprising:

• the enclosed structure having three side walls, a top, a bottom and an opening to the interior of the enclosed structure;
• a door assembly mounted on the opening for controlling access to the interior of the enclosed structure;
• an air plenum disposed on the top of the enclosed structure;
• the thermoelectric heat transfer system mounted one of the side walls;
• the thermoelectric heat transfer system further comprising a condensing section disposed within the air plenum;
• a heat sink disposed within the interior of the enclosed structure;
• a first air circulation fan disposed adjacent to the heat sink to circulate air within the interior of the enclosed structure past the heat sink;
• the air plenum having an air intake louver and an air exhaust louver;
• an air intake fan located inside the air plenum;
• and
• an air diverter to create an airflow path from the air intake louver, through the air intake fan, across the condensing section, and out of the air plenum through the exhaust louver.