Heat exchangers

A heat exchanger comprising:

• a refrigerant inlet header having a refrigerant inlet and positioned in a downstream side of a direction of air flow;
• a refrigerant outlet header positioned in an upstream side of the direction of air flow and having a refrigerant outlet;
• and
• a refrigerant circulating passage for causing the inlet header to communicate with the outlet header therethrough, the circulating passage comprising at least two intermediate headers and a plurality of heat exchange tubes for causing the inlet header and the outlet header to communicate with all the intermediate headers therethrough, the intermediate headers including a refrigerant inflow intermediate header and a refrigerant outflow intermediate header juxtaposed in an upstream-downstream direction of air flow, the inflow intermediate header and the outflow intermediate header being held in communication at one end of the inflow intermediate header,
• wherein a heat exchange core comprises tube groups in a plurality of rows arranged in the upstream-downstream direction, each of the tube groups comprising the plurality of heat exchange tubes arranged at a spacing, the refrigerant inlet header positioned toward one end of each of the heat exchange tubes and having joined thereto the heat exchange tubes of one tube group of at least one row, the refrigerant outlet header positioned toward said one end of each heat exchange tube and having joined thereto the heat exchange tubes of the other tube group, the refrigerant inflow intermediate header positioned toward the other end of each heat exchange tube and having jointed thereto the heat exchange tubes joined to the inlet header, and the refrigerant outflow intermediate header positioned toward said other end of each heat exchange tube and in the upstream side and having joined thereto the heat exchange tubes joined to the outlet header,
• wherein the outflow intermediate header is provided in interior thereof with first flow dividing control means for causing a refrigerant to dividedly flow into the heat exchange tubes joined to the outflow intermediate header uniformly, the first flow dividing control means comprises a first flow dividing control wall having a plurality of refrigerant passing holes for dividing the interior of the outflow intermediate header into first and second spaces arranged one above the other, the inflow intermediate header and the first space of the outflow intermediate header being held in communication at one end of the inflow intermediate header header, and the heat exchange tubes joined to the outflow intermediate header communicate with the second space,
• wherein the inflow intermediate header and the outflow intermediate header are provided by dividing a refrigerant turn tank into a front and a rear portion by separating means, and the turn tank is provided at one end thereof with a communication member for holding the inflow intermediate header and the outflow intermediate header in communication therethrough.

A heat exchanger comprising:

• a refrigerant inlet header having a refrigerant inlet and positioned in a downstream side of a direction of air flow;
• a refrigerant outlet header positioned in an upstream side of the direction of air flow and having a refrigerant outlet;
• and
• a refrigerant circulating passage for causing the inlet header to communicate with the outlet header therethrough, the circulating passage comprising at least two intermediate headers and a plurality of heat exchange tubes for causing the inlet header and the outlet header to communicate with all the intermediate headers therethrough, the intermediate headers including a refrigerant inflow intermediate header and a refrigerant outflow intermediate header juxtaposed in an upstream-downstream direction of air flow, the inflow intermediate header and the outflow intermediate header being held in communication at one end of the inflow intermediate header,
• wherein a heat exchange core comprises tube groups in a plurality of rows arranged in the upstream-downstream direction, each of the tube groups comprising the plurality of heat exchange tubes arranged at a spacing, the refrigerant inlet header positioned toward one end of each of the heat exchange tubes and having joined thereto the heat exchange tubes of one tube group of at least one row, the refrigerant outlet header positioned toward said one end of each heat exchange tube and having joined thereto the heat exchange tubes of the other tube group, the refrigerant inflow intermediate header positioned toward the other end of each heat exchange tube and having jointed thereto the heat exchange tubes joined to the inlet header, and the refrigerant outflow intermediate header positioned toward said other end of each heat exchange tube and in the upstream side and having joined thereto the heat exchange tubes joined to the outlet header,
• wherein the outflow intermediate header is provided in interior thereof with first flow dividing control means for causing a refrigerant to dividedly flow into the heat exchange tubes joined to the outflow intermediate header uniformly, the first flow dividing control means comprises a first flow dividing control wall having a plurality of refrigerant passing holes for dividing the interior of the outflow intermediate header into first and second spaces arranged one above the other, the inflow intermediate header and the first space of the outflow intermediate header being held in communication at one end of the inflow intermediate header header, and the heat exchange tubes joined to the outflow intermediate header communicate with the second space,
• wherein the inflow intermediate header and the outflow intermediate header are provided by dividing a refrigerant turn tank into a front and a rear portion by separating means, and the turn tank comprises a first member having the heat exchange tubes joined thereto, a second member brazed to the first member at a portion thereof opposite to the heat exchange tubes, and two closing members brazed to respective opposite ends of the first and second members, the second member being integrally provided with the separating means and the first flow dividing control wall,
• wherein one of the closing members has two through holes for respectively causing the inflow intermediate header and the first space of the outflow intermediate header in communication with the inflow intermediate header to communicate with outside therethrough, and is provided with a communication member brazed to an outer side thereof for holding the two through holes in communication therethrough.

A heat exchanger comprising:

• a refrigerant inlet header having a refrigerant inlet and positioned in a downstream side of a direction of air flow;
• a refrigerant outlet header positioned in an upstream side of the direction of air flow and having a refrigerant outlet;
• and
• a refrigerant circulating passage for causing the inlet header to communicate with the outlet header therethrough, the circulating passage comprising at least two intermediate headers and a plurality of heat exchange tubes for causing the inlet header and the outlet header to communicate with all the intermediate headers therethrough, the intermediate headers including a refrigerant inflow intermediate header and a refrigerant outflow intermediate header juxtaposed in an upstream-downstream direction of air flow, the inflow intermediate header and the outflow intermediate header being held in communication at one end of the inflow intermediate header,
• wherein a heat exchange core comprises tube groups in a plurality of rows arranged in the upstream-downstream direction, each of the tube groups comprising the plurality of heat exchange tubes arranged at a spacing, the refrigerant inlet header positioned toward one end of each of the heat exchange tubes and having joined thereto the heat exchange tubes of one tube group of at least one row, the refrigerant outlet header positioned toward said one end of each heat exchange tube and having joined thereto the heat exchange tubes of the other tube group, the refrigerant inflow intermediate header positioned toward the other end of each heat exchange tube and having jointed thereto the heat exchange tubes joined to the inlet header, and the refrigerant outflow intermediate header positioned toward said other end of each heat exchange tube and in the upstream side and having joined thereto the heat exchange tubes joined to the outlet header,
• wherein the outflow intermediate header is provided in interior thereof with first flow dividing control means for causing a refrigerant to dividedly flow into the heat exchange tubes joined to the outflow intermediate header uniformly,
• wherein the inlet header is provided in interior thereof with second flow dividing control means for causing the refrigerant to dividedly flow into the heat exchange tubes joined to the inlet header uniformly,
• wherein the second flow dividing control means comprises a second flow dividing control wall having a plurality of refrigerant passing holes for dividing the interior of the inlet header into first and second two spaces arranged one above the other, the refrigerant inlet being in communication with the first space, and the heat exchange tubes joined to the inlet header communicate with the second space,
• wherein the refrigerant passing holes formed in the second flow dividing control wall are arranged at a spacing longitudinally thereof and are smaller than the refrigerant passing holes in the first flow dividing control means.