Refrigerant evaporator

A refrigerant evaporator that exchanges heat between fluid flowing outside to be cooled and refrigerant, comprising

• a first evaporation unit and a second evaporation unit disposed in series in a flow direction of the fluid, wherein:
• each of the first evaporation unit and the second evaporation unit has
• a heat-exchanging core portion in which a plurality of tubes are stacked, the refrigerant flowing through the plurality of tubes, and
• a pair of tank portions connected to both ends of the plurality of tubes to collect or distribute the refrigerant flowing inside the plurality of tubes;
• the heat-exchanging core portion of the first evaporation unit has a first core portion defined by a part of the plurality of tubes and a second core portion defined by a rest of the plurality of tubes;
• the heat-exchanging core portion of the second evaporation unit has a third core portion defined by a part of the plurality of tubes opposing at least a part of the first core portion in the flow direction of the fluid and a forth core portion defined by a part of the plurality of tubes opposing at least a part of the second core portion in the flow direction of the fluid;
• of the pair of tank portions of the first evaporation unit, one tank portion includes a first refrigerant collection portion to collect the refrigerant from the first core portion and a second refrigerant collection portion to collect the refrigerant from the second core portion;
• of the pair of tank portions of the second evaporation unit, one tank portion includes a first refrigerant distribution portion to distribute the refrigerant to the third core portion and a second refrigerant distribution portion to distribute the refrigerant to the fourth core portion;
• the first evaporation unit and the second evaporation unit are coupled via a refrigerant interchanging portion having a first communication portion that introduces refrigerant from the first refrigerant collection portion to the second refrigerant distribution portion and a second communication portion that introduces refrigerant from the second refrigerant collection portion to the first refrigerant distribution portion;
• of the pair of tank portions of the first evaporation unit, the other tank portion includes a first partition member that divides a tank internal space of the other tank portion to a first tank internal space and a second tank internal space in a longitudinal direction of the tube;
• the first partition member has a first communication hole to let the first tank internal space and the second tank internal space communicate with each other;
• of the pair of tank portions of the second evaporation unit, the other tank portion includes a second partition member that divides a tank internal space of the other tank portion to a third tank internal space and a fourth tank internal space in a longitudinal direction of the tube;
• and
• the second partition member has a second communication hole to let the third tank internal space and the fourth tank internal space communicate with each other.

A refrigerant evaporator that exchanges heat between fluid flowing outside to be cooled and refrigerant, comprising

• a first evaporation unit and a second evaporation unit disposed in series in a flow direction of the fluid, wherein:
• each of the first evaporation unit- and the second evaporation unit has
• a heat-exchanging core portion in which a plurality of tubes are stacked, the refrigerant flowing through the plurality of tubes, and
• a pair of tank portions connected to both ends of the plurality of tubes to collect or distribute the refrigerant flowing inside the plurality of tubes;
• the heat-exchanging core portion of the first evaporation unit has a first core portion defined by a part of the plurality of tubes and a second core portion defined by a rest of the plurality of tubes;
• the heat-exchanging core portion of the second evaporation unit has a third core portion defined by a part of the plurality of tubes opposing at least a part of the first core portion in the flow direction of the fluid and a forth core portion defined by a part of the plurality of tubes opposing at least a part of the second core portion in the flow direction of the fluid;
• of the pair of tank portions of the first evaporation unit, one tank portion includes a first refrigerant collection portion to collect the refrigerant from the first core portion and a second refrigerant collection portion to collect the refrigerant from the second core portion;
• of the pair of tank portions of the second evaporation unit, one tank portion includes a first refrigerant distribution portion to distribute the refrigerant to the third core portion and a second refrigerant distribution portion to distribute the refrigerant to the fourth core portion;
• the first evaporation unit and the second evaporation unit are coupled via a refrigerant interchanging portion having a first communication portion that introduces refrigerant from the first refrigerant collection portion to the second refrigerant distribution portion and a second communication portion that introduces refrigerant from the second refrigerant collection portion the first refrigerant distribution portion;
• the first evaporation unit has a refrigerant inlet portion through which refrigerant is introduced into the other tank portion of the first evaporation unit an end of the other tank portion in a stacking direction of the tubes;
• the other tank portion of the first evaporation unit includes a dam portion to stop a flow of liquid phase refrigerant that has flowed into the other tank portion from the refrigerant inlet portion;
• and
• the dam portion is located at a position so as to overlap a boundary between the third core portion and the fourth core portion of the second evaporation unit when viewed in the flow direction of the fluid.