JP2014035169A - Intermediate heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate heat exchanger allowing an engine room of a vehicle to be effectively utilized.SOLUTION: An intermediate heat exchanger 20 includes: a flat hollow casing 21 provided with a first refrigerant flowing passage 22 inside, and further provided with in its peripheral wall, a refrigerant inlet 23 and a refrigerant outlet 24 which are communicated with the first refrigerant flowing passage 22; and a refrigerant flowing pipe 25 which is disposed in the first refrigerant flowing passage 22 in the casing 21, the inside of which is used as a second refrigerant flowing passage, and which is communicated with the outside of the casing 21 at its both ends. The first refrigerant flowing passage 22 in the casing 21 is a low-pressure refrigerant flowing passage, the second refrigerant flowing passage 26 inside the refrigerant flowing pipe 25 is a high-pressure refrigerant flowing passage. The refrigerant inlet 23 of the casing 21 allows the low-pressure refrigerant to flow into the first refrigerant flowing passage 22, and the refrigerant outlet 24 allows the low-pressure refrigerant to flow out from the first refrigerant flowing passage 22. One end portion of the refrigerant flowing pipe 25 is used as an inlet-side end portion 28 allowing the high-pressure refrigerant to flow into the second refrigerant flowing passage 26, and the other end portion is used as an outlet-side end portion 29 allowing the high-pressure refrigerant to flow out.

Description

  The present invention relates to an intermediate heat exchanger, and more particularly to an intermediate heat exchanger for exchanging heat between a low-pressure refrigerant flowing out of an evaporator and a high-pressure refrigerant flowing out of a condenser in a refrigeration cycle used in a vehicle air conditioner.

  In this specification, the term “capacitor” includes a subcool condenser having a condensing part and a supercooling part in addition to a normal condenser.

  Conventionally, as a refrigeration cycle used in a vehicle air conditioner, a compressor, a condenser having a condensing part and a supercooling part, an evaporator, an expansion valve as a decompressor, a gas-liquid separator, and disposed between the condenser and the evaporator In addition, an apparatus including an intermediate heat exchanger for exchanging heat between the high-temperature refrigerant coming out of the supercooling section of the condenser and the low-temperature refrigerant coming out of the evaporator has been proposed (see Patent Document 1). In the refrigeration cycle described in Patent Document 1, the refrigerant supercooled in the condenser supercooling section is further cooled by the low-temperature and low-pressure refrigerant that has come out of the evaporator in the intermediate heat exchanger, whereby the cooling performance of the evaporator is improved. It can be improved.

  The intermediate heat exchanger used in the refrigeration cycle described in Patent Document 1 includes an outer tube and an inner tube arranged at intervals in the outer tube, and the gap between the outer tube and the inner tube is high. The inner pipe is a low-pressure side refrigerant flow path, and a plurality of internal fins projecting radially inward and extending in the length direction are circumferentially spaced on the inner peripheral surface of the inner pipe. A plurality of ridges projecting radially outward and extending in the length direction are provided on the outer peripheral surface of the inner tube at intervals in the circumferential direction, and the fin height of the inner fin is the ridge. It consists of a double-pipe heat exchanger that is higher than the protruding height.

  However, in the case of the intermediate heat exchanger composed of the double-pipe heat exchanger described in Patent Document 1, in order to further improve the heat exchange performance between the low-pressure refrigerant flowing out of the evaporator and the high-pressure refrigerant flowing out of the condenser, It is necessary to increase the heat transfer area between the low-pressure refrigerant and the high-pressure refrigerant by increasing the length of the outer tube and the inner tube of the tubular heat exchanger.

  In order to increase the heat transfer area between the low-pressure refrigerant and the high-pressure refrigerant by increasing the lengths of the outer tube and the inner tube of the double-tube heat exchanger described in Patent Document 1, a double-tube heat exchanger It is considered that it is common to bend it three-dimensionally and arrange it in the engine room. However, in this case, an extra space is required in the engine room, and the space in the engine room cannot be effectively used. There's a problem.

JP 2009-162395 A

  An object of the present invention is to provide an intermediate heat exchanger that solves the above-described problems and can effectively utilize the inside of an engine room of a vehicle.

  In order to achieve the above object, the present invention comprises the following aspects.

1) An intermediate heat exchanger having two refrigerant flow passages for exchanging heat between the low-pressure refrigerant flowing out of the evaporator and the high-pressure refrigerant flowing out of the condenser,
A flat, hollow casing having a refrigerant inlet and a refrigerant outlet communicating with the first refrigerant flow passage in the peripheral wall and a first refrigerant flow passage in the casing and provided in the first refrigerant flow passage. Is a second refrigerant flow passage, and an intermediate heat exchanger provided with a refrigerant flow pipe whose both ends communicate with the outside of the casing.

  2) The first refrigerant flow passage in the casing is a low-pressure refrigerant flow passage, the refrigerant inlet of the casing allows the low-pressure refrigerant flowing out of the evaporator to flow into the first refrigerant flow passage, and the refrigerant outlet is the first refrigerant flow The low-pressure refrigerant is caused to flow out of the passage, the second refrigerant flow passage inside the refrigerant flow pipe is a high-pressure refrigerant flow path, and one end portion of the refrigerant flow pipe passes the second high-pressure refrigerant flowing out of the capacitor. The intermediate heat exchanger according to 1), wherein the intermediate heat exchanger is an inlet-side end portion that flows into the refrigerant flow passage, and the other end portion is an outlet-side end portion that flows out the high-pressure refrigerant to the expansion valve side.

3) The inlet side end and the outlet side end to the second refrigerant flow passage in the refrigerant flow pipe are respectively projected outside the casing,
An expansion valve connecting member that has a refrigerant inflow passage that communicates with the refrigerant inlet and through which the low-pressure refrigerant flows and is fixed to the outlet side end of the refrigerant circulation pipe is provided outside the casing, and the first refrigerant is connected to the expansion valve connecting member. An expansion valve having a flow path and a second refrigerant flow path is connected, and low-pressure refrigerant that flows out of the evaporator and passes through the first refrigerant flow path of the expansion valve flows into the refrigerant inflow path of the expansion valve connecting member. The intermediate heat exchanger according to 2) above, wherein the high-pressure refrigerant flowing out from the outlet side end of the refrigerant flow pipe flows through the second refrigerant flow path of the expansion valve and is depressurized.

  4) A pipe joint member having a refrigerant outflow passage that communicates with the refrigerant outlet and having an inlet side end fixed to the refrigerant flow pipe is fixed outside the casing. A pipe that sends the low-pressure refrigerant that flows out from the refrigerant flow path and passes through the refrigerant flow path of the pipe joint member to the compressor, and a pipe that sends the high-pressure refrigerant that flows out from the condenser to the second refrigerant flow path of the refrigerant flow pipe are connected. The intermediate heat exchanger as described in 3) above.

  5) The intermediate heat exchanger according to any one of 2) to 4), wherein an outer side of the casing is covered with a heat insulating material.

  6) The intermediate according to any one of 1) to 5) above, wherein the first refrigerant flow passage in the casing and the refrigerant flow pipe arranged in the first refrigerant flow passage in the casing are each meandering. Heat exchanger.

  According to the above intermediate heat exchangers 1) to 6), a flat hollow casing having a first refrigerant flow passage therein and having a refrigerant inlet and a refrigerant outlet communicating with the first refrigerant flow passage on a peripheral wall. And a refrigerant flow pipe that is disposed in the first refrigerant flow passage in the casing and has a second refrigerant flow passage in the casing and both ends communicating with the outside of the casing. Increasing the heat transfer area between the refrigerant flowing in the first refrigerant flow passage and the refrigerant flowing in the second refrigerant flow passage by increasing the length of the second refrigerant flow passage and the length of the refrigerant flow pipe. Is possible. And even if it is a case where a casing is enlarged, since a casing is a flat hollow shape, it becomes possible to arrange | position along the wall etc. which are provided between a vehicle interior and an engine room, and patent document 1 description. Compared to the case of bending an intermediate heat exchanger composed of a double-pipe heat exchanger, the required space in the engine room is reduced, and the space in the engine room can be used effectively.

  Moreover, regardless of whether the vehicle is a right steering wheel or a left steering wheel, it is possible to respond without requiring extra space, and versatility is enhanced.

  According to the intermediate heat exchanger of 2) above, the first refrigerant flow passage in the casing is a low-pressure refrigerant flow passage, and the refrigerant inlet of the casing causes the low-pressure refrigerant flowing out of the evaporator to flow into the first refrigerant flow passage. At the same time, the refrigerant outlet allows low-pressure refrigerant to flow out of the first refrigerant flow passage, the second refrigerant flow passage inside the refrigerant flow tube is a high-pressure refrigerant flow passage, and the second refrigerant in the refrigerant flow tube. One end portion of the flow passage serves as an inlet-side end portion for allowing the high-pressure refrigerant flowing out from the condenser to flow into the second refrigerant flow passage, and the other end portion thereof includes an outlet-side end portion for allowing the high-pressure refrigerant to flow out to the expansion valve side. Therefore, the pressure resistance against the internal pressure of the flat hollow casing will not be insufficient.

  According to the intermediate heat exchanger of 3) above, the expansion valve can be connected relatively easily.

  According to the intermediate heat exchanger of the above 4), the high-pressure refrigerant flowing out of the first refrigerant flow passage of the casing and the low-pressure refrigerant that has passed through the refrigerant outflow passage of the pipe joint member to the compressor and the high-pressure refrigerant flowing out of the condenser The piping sent to the second refrigerant flow passage of the refrigerant distribution pipe can be connected relatively easily.

  According to the intermediate heat exchanger of the above 5), the relatively low-temperature low-pressure refrigerant flowing through the first refrigerant flow passage in the casing, which is the low-pressure refrigerant flow passage, is heated by the atmospheric temperature in the engine room of the vehicle. It is suppressed. Therefore, the relatively high-temperature high-pressure refrigerant flowing in the high-pressure refrigerant flow passage can be efficiently cooled.

  According to the intermediate heat exchanger of 6), the heat transfer area between the refrigerant flowing in the first refrigerant flow passage and the refrigerant flowing in the second refrigerant flow passage can be effectively increased.

It is a top view which shows the specific structure of the vehicle air conditioner provided with the intermediate heat exchanger by this invention. It is a figure which shows schematic structure of the vehicle air conditioner provided with the intermediate heat exchanger by this invention. 1 is a partially cutaway perspective view showing an overall configuration of an intermediate heat exchanger according to the present invention. It is the top view which abbreviate | omitted the heat insulating material which covers the outer side of the casing of the intermediate heat exchanger of FIG. It is the sectional view on the AA line of FIG. It is the disassembled perspective view which abbreviate | omitted the heat insulating material which covers the outer side of the casing of the intermediate heat exchanger of FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the intermediate heat exchanger of the present invention is applied to a vehicle air conditioner mounted on a vehicle.

  In the following description, the front side of the vehicle, that is, the lower side of FIGS. 1 and 4 is referred to as the front side, and the opposite side is referred to as the rear side. It is assumed to be up and down and left and right.

  In the following description, the term “aluminum” includes aluminum alloys in addition to pure aluminum.

  1 and 2 show the configuration of a vehicle air conditioner using an intermediate heat exchanger according to the present invention, and FIGS. 3 to 6 show the intermediate heat exchanger according to the present invention.

  1 and 2, the vehicle air conditioner has a compressor (1), a condenser (3), a liquid receiver (4) as a gas-liquid separator, and a supercooling part (5) and is compressed. A condenser (2) for cooling the refrigerant compressed by the machine (1), a first refrigerant flow path (7) and a second refrigerant flow path (8), which are cooled by the condenser (2) and excessive. An expansion valve (6) for depressurizing the cooled high-pressure refrigerant, an evaporator (9) for evaporating the depressurized refrigerant, a high-pressure refrigerant flowing out of the condenser (2) and before being depressurized by the expansion valve (6) An intermediate heat exchanger (20) for exchanging heat with the low-pressure refrigerant flowing out of the evaporator (9), and the compressor (1), condenser (2) and intermediate heat exchanger (20) are connected to the engine room (10 ) And an expansion valve (6) and an evaporator (9) are arranged in the passenger compartment (11).

  As shown in FIGS. 3 to 6, the intermediate heat exchanger (20) has a first refrigerant flow passage (22) provided therein, and a refrigerant inlet communicating with the first refrigerant flow passage (22) in the peripheral wall. (23) and an aluminum flat hollow casing (21) having a refrigerant outlet (24), a first refrigerant flow passage (22) in the casing (21), and the inside being a second refrigerant flow passage (26) And an aluminum refrigerant circulation pipe (25) having both ends communicating with the outside of the casing (21).

  The casing (21) has a flat, vertically long rectangular parallelepiped shape with a reduced thickness in the front-rear direction, and a meandering first refrigerant flow passage (22) is provided therein. The first refrigerant flow passage (22) extends in the vertical direction and communicates with a plurality of straight portions (22a) arranged side by side in the left-right direction and adjacent straight portions (22a) alternately in the upper part and the lower part. (22b), which is provided by partitioning the inside of the casing (21) with a partition wall (27), and both ends of the first refrigerant flow passage (22) are on the upper side. The refrigerant inlet (23) is provided at the upper end of the right side wall (21a) of the casing (21), and the refrigerant outlet (24) is provided at the upper end of the left side wall (21b) of the casing (21). The casing (21) is formed by brazing the front and rear constituent members (21A).

  The refrigerant flow pipe (25) extends in the vertical direction and alternately connects a plurality of straight pipe portions (25a) arranged side by side in the left-right direction and the adjacent straight pipe portions (25a) at the upper end portion and the lower end portion. It consists of a bent pipe part (25b), and is disposed in the meandering first refrigerant flow passage (22) of the casing (21). One end of the refrigerant flow pipe (25), in this case, the upper end of the left straight pipe section (25a) protrudes upward through the upper wall (21c) of the casing (21), and the length direction of the protrusion The intermediate portion is bent to the left, and the one end portion is an inlet side end portion (28) through which the refrigerant flows into the second refrigerant flow passage (26). In addition, the other end of the refrigerant flow pipe (25), here the upper end of the rightmost straight pipe part protrudes upward through the upper wall (21c) of the casing (21), and the length direction of the protrusion The intermediate portion is bent rearward, and the other end portion is an outlet side end portion (29) through which the refrigerant flows out of the second refrigerant flow passage (26).

  Here, the first refrigerant flow passage (22) in the casing (21) is a low-pressure refrigerant flow passage, and the refrigerant inlet (23) of the casing (21) converts the low-pressure refrigerant flowing out of the evaporator (9) into the first refrigerant. While flowing into the flow passage (22), the refrigerant outlet (24) allows low-pressure refrigerant to flow out of the first refrigerant flow passage (22). The second refrigerant flow passage (26) inside the refrigerant flow pipe (25) is a high-pressure refrigerant flow passage, and the inlet side end (28) of the second refrigerant flow passage (26) of the refrigerant flow pipe (25). However, the high-pressure refrigerant that has flowed out of the condenser (2) flows into the second refrigerant flow passage (26), and the outlet side end (29) causes the high-pressure refrigerant to flow out to the expansion valve (6) side.

  Outside of the casing (21), it is made of aluminum having a refrigerant inflow passage (32) that communicates with the refrigerant inlet (23) and through which the low-pressure refrigerant flows, and the outlet side end (29) of the refrigerant flow pipe (25) is fixed. An expansion valve connecting member (31) is provided. An expansion valve (6) having a first refrigerant channel (7) and a second refrigerant channel (8) is connected to the expansion valve connecting member (31), and the refrigerant inflow passage of the expansion valve connecting member (31) (32), the low-pressure refrigerant flowing out of the evaporator (9) and passing through the first refrigerant flow path (7) of the expansion valve (6) flows, from the outlet side end (29) of the refrigerant flow pipe (25). The high-pressure refrigerant that has flowed out flows through the second refrigerant flow path (8) of the expansion valve (6) and is depressurized. The expansion valve (6) is attached to the side of the wall (12) provided between the engine room (10) and the vehicle compartment (11) facing the inside of the vehicle compartment (11) (see FIG. 1). .

  In addition, an aluminum pipe joint member having a refrigerant outflow passage (34) communicating with the refrigerant outlet (24) and the inlet side end (28) of the refrigerant flow pipe (25) fixed to the outside of the casing (21) ( 33) and the pipe joint member (33) is used to flow out from the first refrigerant flow path (22) of the casing (21) and to connect the refrigerant outflow path (34) of the pipe joint member (33). A pipe for sending the low-pressure refrigerant that has passed to the compressor (1) and a pipe for sending the high-pressure refrigerant that has flowed out of the condenser (2) to the second refrigerant flow passage (26) of the refrigerant flow pipe (25) are connected. ing.

  Except for the outlet side end (29) of the refrigerant flow pipe (25), the expansion valve connecting member (31), the inlet side end (28) of the refrigerant flow pipe (25), and the pipe joint member (33). The entire outside of the casing (21) is covered with a heat insulating material (35).

  In the vehicle air conditioner provided with the intermediate heat exchanger (20) described above, when the compressor (1) is operated, the high-temperature and high-pressure gas-liquid mixed phase refrigerant compressed by the compressor (1) is the condenser (2). After being cooled and condensed by the condensing part (3), it flows into the receiver (4) and is separated into two phases, and then flows into the supercooling part (5) to be supercooled. . The supercooled liquid phase refrigerant passes through the second refrigerant flow path (26) from the inlet side end (28) of the refrigerant flow pipe (25) fixed to the pipe joint member (33) of the intermediate heat exchanger (20). After entering the second refrigerant flow passage (26), the expansion valve (6) is connected to the expansion valve (6) from the outlet side end (29) of the refrigerant flow pipe (25) fixed to the expansion valve connecting member (31). 2 Enters the refrigerant flow path (8), is decompressed here, flows into the evaporator (9), and cools the air flowing through the ventilation gap while flowing through the evaporator (9) to become a gas phase.

  The relatively low-temperature and low-pressure refrigerant that has passed through the evaporator (9) passes through the first refrigerant passage (7) of the expansion valve (6), the refrigerant inflow passage (32) of the expansion valve connecting member (31), and the intermediate heat exchanger. After passing through the refrigerant inlet (23) of the casing (21) of (20) and entering the first refrigerant passage (22) of the intermediate heat exchanger (20) and flowing through the first refrigerant passage (22), the pipe The refrigerant is sent to the compressor (1) through the refrigerant discharge path (34) and the pipe of the joint member (33).

  Here, the high-temperature and high-pressure refrigerant sent from the condenser (2) and entering the second refrigerant flow passage (26) of the refrigerant flow pipe (25) of the intermediate heat exchanger (20) is transferred to the second refrigerant flow passage ( 26) While flowing through the inside, the refrigerant is cooled by the low-temperature and low-pressure refrigerant flowing through the first refrigerant flow passage (22) of the intermediate heat exchanger (20).

  The intermediate heat exchanger according to the present invention includes a compressor, a condenser having a condensing unit, a supercooling unit, and a liquid receiver, an evaporator, and an expansion valve serving as a decompressor. It is suitably used as an exchanger.

(2): Capacitor
(6): Expansion valve
(7): First refrigerant flow path
(8): Second refrigerant flow path
(9): Evaporator
(20): Intermediate heat exchanger
(21): Casing
(22): First refrigerant flow path
(23): Refrigerant inlet
(24): Refrigerant outlet
(25): Refrigerant distribution pipe
(26): Second refrigerant flow path
(28): Inlet end
(29): Exit side end
(31): Expansion valve connecting member
(32): Refrigerant inflow path
(33): Pipe connection member
(34): Refrigerant outflow path
(35): Insulation

Claims (6)

An intermediate heat exchanger having two refrigerant flow passages for exchanging heat between the low-pressure refrigerant flowing out of the evaporator and the high-pressure refrigerant flowing out of the condenser,
A flat, hollow casing having a refrigerant inlet and a refrigerant outlet communicating with the first refrigerant flow passage in the peripheral wall and a first refrigerant flow passage in the casing and provided in the first refrigerant flow passage. Is a second refrigerant flow passage, and an intermediate heat exchanger provided with a refrigerant flow pipe whose both ends communicate with the outside of the casing. The first refrigerant flow passage in the casing is a low-pressure refrigerant flow passage, the refrigerant inlet of the casing allows low-pressure refrigerant that has flowed out of the evaporator to flow into the first refrigerant flow passage, and the refrigerant outlet is in the first refrigerant flow passage. The second refrigerant flow passage inside the refrigerant flow pipe is a high pressure refrigerant flow passage, and one end portion of the refrigerant flow pipe passes the high pressure refrigerant flowing out from the condenser to the second refrigerant flow. 2. The intermediate heat exchanger according to claim 1, wherein the intermediate heat exchanger is an inlet side end portion that flows into the passage, and the other end portion is an outlet side end portion that allows the high-pressure refrigerant to flow out toward the expansion valve. The inlet side end and the outlet side end to the second refrigerant flow passage in the refrigerant flow pipe are respectively projected to the outside of the casing,
An expansion valve connecting member that has a refrigerant inflow passage that communicates with the refrigerant inlet and through which the low-pressure refrigerant flows and is fixed to the outlet side end of the refrigerant circulation pipe is provided outside the casing, and the first refrigerant is connected to the expansion valve connecting member. An expansion valve having a flow path and a second refrigerant flow path is connected, and low-pressure refrigerant that flows out of the evaporator and passes through the first refrigerant flow path of the expansion valve flows into the refrigerant inflow path of the expansion valve connecting member. The intermediate heat exchanger according to claim 2, wherein the high-pressure refrigerant that has flowed out from the outlet side end of the refrigerant flow pipe flows through the second refrigerant flow path of the expansion valve and is depressurized. A pipe joint member having a refrigerant outflow passage communicating with the refrigerant outlet and fixed at the inlet end of the refrigerant flow pipe is provided outside the casing, and the first refrigerant flow of the casing is utilized using the pipe joint member. A pipe that sends out the low-pressure refrigerant that has flowed out of the passage and passed through the refrigerant outlet passage of the pipe joint member to the compressor, and a pipe that sends the high-pressure refrigerant that has flowed out of the condenser to the second refrigerant flow passage of the refrigerant flow pipe are connected. The intermediate heat exchanger according to claim 3. The intermediate heat exchanger according to any one of claims 2 to 4, wherein an outer side of the casing is covered with a heat insulating material. The intermediate heat exchanger according to any one of claims 1 to 5, wherein each of the first refrigerant flow passage in the casing and the refrigerant flow pipe disposed in the first refrigerant flow passage in the casing has a meandering shape. .

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