Laminated Heat Exchanger

Abstract

An evaporator implemented by a laminated heat exchanger includes a refrigerant inlet header section, a refrigerant outlet header section, and plural inter mediate header sections. A sixth intermediate header section includes a refrigerant channel allowing refrigerant flow in the longitudinal direction thereof and whose downstream end with respect to the refrigerant flow direction is closed, and causes refrigerant to dividedly flow into a plurality of refrigerant flow tube portions. Refrigerant that has flown into the refrigerant inlet header section from a refrigerant inlet flows into the refrigerant outlet header section through the refrigerant flow tube portions and through the intermediate header sections and flows out from a refrigerant outlet. A resistive plate portion within the sixth intermediate header section blocks the refrigerant channel thereof extending in the longitudinal direction thereof. A resistive hole in the resistive plate portion imparts resistance to refrigerant that flows through the refrigerant channel.

1 : A laminated heat exchanger comprising a plurality of flat, hollow members, each of the flat, hollow members comprising two vertically elongated metal plates having perimetric edge portions joined together, a bulging refrigerant flow tube portion being formed between the two metal plates, a bulging header formation portion being connected to each of opposite ends of the refrigerant flow tube portion, the header formation portions of adjacent flat, hollow members arranged in a laminated condition being joined together, clearances between the refrigerant flow tube portions of adjacent flat, hollow members serving as air-passing clearances, the header formation portions of the flat, hollow members forming a refrigerant inlet header section having a refrigerant inlet, a refrigerant outlet header section having a refrigerant outlet, and a plurality of intermediate header sections, at least one of all the header sections serving as a refrigerant-flow-dividing header section which has a refrigerant channel allowing flow of refrigerant in the longitudinal direction thereof and having a downstream end with respect to the refrigerant flow direction closed and which causes refrigerant to dividedly flow into a plurality of refrigerant flow tube portions, refrigerant flowing into the refrigerant inlet header section from the refrigerant inlet, flowing through the refrigerant flow tube portions and through the intermediate header sections, flowing into the refrigerant outlet header section, and flowing out from the refrigerant outlet, wherein a resistive portion is provided in at least one of the refrigerant-flow-dividing header sections so as to impart resistance to refrigerant that flows through the refrigerant channel extending in a longitudinal direction of the refrigerant-flow-dividing header section.  
     
     
         2 : A laminated heat exchanger according to  claim 1 , wherein the resistive portion comprises a resistive hole formed in a resistive plate portion that is provided within the refrigerant-flow-dividing header section in a manner to block the refrigerant channel thereof.  
     
     
         3 : A laminated heat exchanger according to  claim 2 , wherein the resistive plate portion is a portion of a flat plate of metal sandwiched between and joined to two metal plates used to form the flat, hollow member the portion of the flat plate being present within the refrigerant-flow-dividing header section, and a portion of the flat plate that is present in another header section having the refrigerant channel has a refrigerant passage hole formed therein and having a cross-sectional area equal to that of the refrigerant channel.  
     
     
         4 : A laminated heat exchanger according to  claim 2 , wherein a plurality of resistive plate portions are provided within at least one refrigerant-flow-dividing header section, and the resistive hole is formed in each of the resistive plate portions.  
     
     
         5 : A laminated heat exchanger according to  claim 4 , wherein the resistive holes of different sizes are mixedly present.  
     
     
         6 : A laminated heat exchanger according to  claim 4 , wherein the resistive holes of different vertical positions within the corresponding refrigerant channels are mixedly present.  
     
     
         7 : A laminated heat exchanger according to  claim 2 , wherein at least one resistive plate portion is provided within each of a plurality of refrigerant-flow-dividing header sections, and the resistive hole is formed in the resistive plate portion.  
     
     
         8 : A laminated heat exchanger according to  claim 7 , wherein the resistive holes of different sizes are mixedly present.  
     
     
         9 : A laminated heat exchanger according to  claim 7 , wherein the resistive holes of different vertical positions within the corresponding refrigerant channels are mixedly present.  
     
     
         10 : A laminated heat exchanger according to  claim 2 , wherein the size of the resistive hole is 1/60 to 1/10 the cross-sectional area of the refrigerant channel of the refrigerant-flow-dividing header section.  
     
     
         11 : A laminated heat exchanger according to  claim 2 , wherein a guide portion is provided on a downstream-side surface of the resistive plate portion with respect to the refrigerant flow direction so as to guide refrigerant having passed through the resistive hole, toward the refrigerant flow tube portion near the resistive plate portion.  
     
     
         12 : A laminated heat exchanger according to  claim 1 , wherein the flat, hollow member comprises the two vertically extending refrigerant flow tube portions spaced apart from each other in an air flow direction and the two header formation portions provided at each of the upper and lower end portions of the fiat, hollow member, the two header formation portions being connected to corresponding upper ends of the two refrigerant flow tube portions and spaced apart from each other in the air flow direction, and the other two header formation portions being connected to corresponding lower ends of the two refrigerant flow tube portions and spaced apart from each other in the air flow direction.  
     
     
         13 : A laminated heat exchanger according to  claim 12  comprising a refrigerant inlet header section, a refrigerant outlet header section arranged upstream of the refrigerant inlet header section with respect to the air flow direction, a first intermediate header section arranged under the refrigerant inlet header section, a second intermediate header section arranged in tandem alignment with the first intermediate header section, a third intermediate header section arranged above the second intermediate header section and in tandem alignment with the refrigerant inlet header section, a fourth intermediate header section arranged upstream of the third intermediate header section with respect to the air flow direction and in tandem alignment with the refrigerant outlet header section, a fifth intermediate header section arranged under the fourth intermediate header section, and a sixth intermediate header section arranged under the refrigerant outlet header section and in tandem alignment with the fifth intermediate header section, wherein each of the refrigerant inlet header section, the first intermediate header section, the second intermediate header section, and the third intermediate header section comprises the header formation portions of the flat, hollow members located toward a downstream side with respect to the air flow direction; each of the refrigerant outlet header section, the fourth intermediate header section, the fifth intermediate header section, and the sixth intermediate header section comprises the header formation portions of the flat, hollow members located toward an upstream side with respect to the air flow direction; the refrigerant flow tube portions of the flat, hollow members establish communication between the refrigerant inlet header section and the first intermediate header section, communication between the second intermediate header section and the third intermediate header section, communication between the fourth intermediate header section and the fifth intermediate header section, and communication between the sixth intermediate header section and the refrigerant outlet header section; the third intermediate header section and the fourth intermediate header section communicate with each other via communication channels formed in the flat, hollow members; each of the refrigerant inlet header section, the second intermediate header section, and the sixth intermediate header section serves as a refrigerant-flow-dividing header section which has a refrigerant channel allowing flow of refrigerant in the longitudinal direction thereof and having a downstream end with respect to the refrigerant flow direction closed and which causes refrigerant to dividedly flow into a plurality of refrigerant flow tube portions; each of the refrigerant outlet header section, the first intermediate header section, and the fifth intermediate header section serves as a refrigerant-flow-joining header section which has a refrigerant channel allowing flow of refrigerant in the longitudinal direction thereof and having a downstream end with respect to the refrigerant flow direction open and which causes refrigerant flowing out from a plurality of refrigerant flow tube portions to join together; the refrigerant channel of the refrigerant inlet header section communicates with the refrigerant inlet; the refrigerant channel of the refrigerant outlet header section communicates with the refrigerant outlet; the refrigerant channel of the first intermediate header section communicates with that of the second intermediate header section; and the refrigerant channel of the fifth intermediate header section communicates with that of the sixth intermediate header section.  
     
     
         14 : A laminated heat exchanger according to  claim 1 , wherein the flat, hollow member comprises a hairpin refrigerant flow tube portion, which comprises two vertically extending, bulging linear portions spaced apart from each other in the air flow direction and a bulging communication portion for establishing communication between the two bulging linear portions at upper ends thereof, and two header formation portions provided at the lower end portion of the flat, hollow member, the two header formation portions being connected to corresponding opposite ends of the refrigerant flow tube portion and spaced apart from each other in the air flow direction.  
     
     
         15 : A laminated heat exchanger according to  claim 14  comprising a refrigerant inlet header section, a refrigerant outlet header section arranged in tandem alignment with the refrigerant inlet header section, a first intermediate header section arranged downstream of the refrigerant inlet header section with respect to the air flow direction, and a second intermediate header section arranged downstream of the refrigerant outlet header section with respect to the air flow direction and in tandem alignment with the first intermediate header section, wherein each of the refrigerant inlet header section and the refrigerant outlet header section comprises the header formation portions of the flat, hollow members located toward an upstream side with respect to the air flow direction; each of the first intermediate header section and the second intermediate header section comprises the header formation portions of the flat, hollow members located toward a downstream side with respect to the air flow direction; the refrigerant flow tube portions of the flat, hollow members establish communication between the refrigerant inlet header section and the first intermediate header section and communication between the second intermediate header section and the refrigerant outlet header section; each of the refrigerant inlet header section and the second intermediate header section serves as a refrigerant-flow-dividing header section which has a refrigerant channel allowing flow of refrigerant in the longitudinal direction thereof and having a downstream end with respect to the refrigerant flow direction closed and which causes refrigerant to dividedly flow into a plurality of refrigerant flow tube portions; each of the refrigerant outlet header section and the first intermediate header section serves as a refrigerant-flow-joining header section which has a refrigerant channel allowing flow of refrigerant in the longitudinal direction thereof and having a downstream end with respect to the refrigerant flow direction open and which causes refrigerant flowing out from a plurality of refrigerant flow tube portions to join together; the refrigerant channel of the refrigerant inlet header section communicates with the refrigerant inlet; the refrigerant channel of the refrigerant outlet header section communicates with the refrigerant outlet; and the refrigerant channel of the first intermediate header section communicates with that of the second intermediate header section.  
     
     
         16 : A refrigeration cycle comprising a compressor, a condenser, and an evaporator, the evaporator comprising a laminated heat exchanger according to  claim 1 .  
     
     
         17 : A vehicle having installed therein a refrigeration cycle according to  claim 16  as a vehicle air conditioner.