JP2005083741A - Air conditioner having heat exchanger and refrigerant switching means - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase an enthalpy difference between an inlet and an outlet of an evaporator in an air conditioner to enhance a refrigerant flow rate. <P>SOLUTION: In this cooling and heating unit formed of an interior heat exchanger, an exterior heat exchanger, a fourway valve and a compressor for compressing a refrigerant, a double tube heat exchanger 103 is arranged in front of an inlet of the compressor 101, a refrigerant flow switching device 106 is arranged between the interior heat exchanger 104 and the exterior heat-exchanger 102, so as to conduct effective heat exchange in cooling and heating operations, and a refrigerant flow directions in an inlet and an outlet of the double tube heat-exchanger 103 are maintained fixedly even in the switching between the cooling and heating operations. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an apparatus capable of heat exchange and cooling / heating of a refrigerant, comprising a double pipe heat exchanger on the compressor inlet side, an outdoor heat exchanger having a condenser, and an indoor heat exchanger having an evaporator. By constructing a refrigerant flow switching device between the two, the refrigerant is condensed by effectively exchanging heat between the medium-temperature and high-pressure liquid refrigerant on the condenser outlet side and the low-temperature and low-pressure superheated refrigerant on the evaporator outlet side during cooling operation. Increases the superheat degree of the liquid refrigerant on the outlet side of the machine to improve the refrigerant flow characteristics of the expansion device, reduces the enthalpy on the inlet side of the evaporator, and increases the enthalpy difference between the inlet and outlet of the evaporator, so that the cooling capacity Relates to a device that increases.

  In addition, the heat exchanger has a double-pipe structure, and the heat exchanger tube that performs heat exchange in a counter flow or parallel flow and the core are in line contact or surface contact so that the core and the core are in contact over a certain area. It is related with the structure which can improve heat-transfer performance.

  Generally, when an apparatus that provides at least one of cooling and heating, such as an air conditioner or a heat pump, is used indoors, it serves to maintain the room temperature at a desired appropriate temperature regardless of the outside air temperature.

  If the room temperature is kept constant at a desired temperature, the user feels comfortable.

  FIG. 1 shows a general refrigeration cycle.

  As shown in the drawings, a compressor 1 that changes a low-temperature and low-pressure gaseous refrigerant to a high-temperature and high-pressure gaseous refrigerant, and a high-temperature and high-pressure gaseous refrigerant that is changed by the compressor 1 is changed to a medium-temperature and high-pressure liquid. A condenser 2 that releases heat to the outside while being changed to a refrigerant in a state; an expansion mechanism 3 that changes a medium-temperature and high-pressure liquid refrigerant changed by the condenser 2 to a low-temperature and low-pressure refrigerant; and the expansion mechanism 3 The evaporator 4 absorbs external heat while converting the low-temperature and low-pressure refrigerant changed in the above into a gaseous state, and each component is connected by a refrigerant pipe.

  The refrigeration cycle apparatus can store food freshly by using the evaporator to absorb heat from the outside and use the condenser to release the heat to the outside. Used for refrigerators and air conditioners.

  FIG. 2 is a state diagram showing a cooling cycle of a general air conditioner.

  As shown in the drawing, the low-temperature and low-pressure gas-phase (gas) refrigerant flowing into the compressor 1 from the indoor heat exchanger 4 is pressurized to a high-temperature and high-pressure gas-phase state through the pressurizing action of the compressor 1. At the same time, the refrigerant discharged to the outdoor heat exchanger 2 through the four-way valve 5 switched so as to form a cooling cycle, and the refrigerant discharged to the outdoor heat exchanger 2 flows inside the outdoor heat exchanger 2. While flowing, the outdoor fan 7 is driven to exchange heat with the external air sucked into the outdoor heat exchanger, thereby causing a phase change to a liquid phase state of medium temperature and high pressure.

  The refrigerant thus phase-changed is discharged to the expansion valve 3 and at the same time, the refrigerant is reduced to a low-temperature and low-pressure liquid state so that the evaporation operation can be easily performed while flowing in the expansion valve 3. After the refrigerant discharged to the indoor heat exchanger 4 and the refrigerant discharged to the indoor heat exchanger 4 exchanges heat with the ambient air of the indoor heat exchanger 4 to cause a phase change to a low-temperature and low-pressure gas phase state, It flows into the compressor 1 again through the four-way valve 5.

  Thus, the ambient air heat-exchanged with the refrigerant decompressed via the expansion valve 3 in the indoor heat exchanger 4 is deprived of heat by the refrigerant and changes into cold cold air, and the cold air passes through the indoor fan 6. It is discharged into the room and the cooling process of the air conditioner is completed.

  FIG. 3 is a state diagram showing a heating cycle of a general air conditioner.

  As can be seen in the drawing, by forming a cycle opposite to the above-described cooling stroke, the low-temperature and low-pressure gas-phase refrigerant flowing into the compressor 1 from the outdoor heat exchanger 2 is passed through the pressurizing action of the compressor 1. At the same time as being pressurized to a high-temperature and high-pressure gas phase, it is discharged to the indoor heat exchanger 4 through the four-way valve 5 switched so as to form a heating cycle, and with the ambient air of the indoor heat exchanger 4 When the ambient air that has been discharged into the expansion valve 3 and undergoes heat exchange with the high-temperature and high-pressure gas-phase refrigerant at this time is changed into hot air by the heat of the refrigerant, after undergoing a phase change to a liquid phase state of medium and high pressure through heat exchange. At the same time, it is discharged into the room through the indoor fan 6 to raise the room temperature.

  In addition, the refrigerant discharged to the expansion valve 3 is decompressed to a low-temperature and low-pressure liquid phase so that the evaporating action is smoothly performed in the outdoor heat exchanger 2 and then discharged to the outdoor heat exchanger 2 to perform the outdoor heat exchange. The refrigerant discharged to the vessel 2 undergoes a phase change to a low-temperature and low-pressure gas phase state through heat exchange with the external air flowing into the outdoor heat exchanger, and then returns to the compressor 1 via the four-way valve 5 again. Inflow.

  FIG. 4 is a configuration diagram schematically showing a general air-conditioning apparatus.

  As shown in the drawing, when the cooling / heating apparatus is in cooling operation, the refrigerant gas discharged from the compressor 1 is separated from the oil by the oil separator 8, and the separated refrigerant gas passes through the four-way valve 5. After flowing into the outdoor heat exchanger 2, the refrigerant changes to a low-temperature and low-pressure refrigerant state through the expansion valve and flows into the indoor heat exchanger 4.

  The refrigerant gas evaporated in the indoor heat exchanger 4 is exchanged with indoor air, and then flows into the accumulator 9 through the four-way valve 5. The refrigerant gas that has flowed into the accumulator 9 is sucked into the compressor 1. While circulating continuously.

  On the other hand, during the heating operation, the refrigerant gas discharged from the compressor 1 is separated from the oil while passing through the oil separator 8, and this refrigerant gas passes through the indoor heat exchanger 4 via the four-way valve 5. The refrigerant is condensed and heat exchanged with the room air. Next, the refrigerant changes into a low-temperature and low-pressure refrigerant state while passing through the expansion valve, and evaporates while passing through the outdoor heat exchanger 2.

  The evaporated refrigerant gas flows into the accumulator 9 via the four-way valve 5 and then circulates while being sucked into the compressor 1.

  FIG. 5 is a configuration diagram showing that a double pipe heat exchanger is applied to a general air conditioner.

  As can be seen from the drawings, a double-tube heat exchanger 10 is mounted between the condenser 1 that is an outdoor heat exchanger and the expansion device.

  The refrigerant compressed by the compressor 1 flows into the outdoor heat exchanger 2, and the outdoor heat exchanger exchanges heat with the outside air outside to exchange heat with the double pipe heat exchanger 10 described above. After performing, it flows into the evaporator 4 which is an indoor heat exchanger via the expansion apparatus 3. FIG.

  At this time, while exchanging heat with the indoor air, the indoor temperature is maintained at a preset low temperature, and then the heat is exchanged via the double pipe heat exchanger 10 to the compressor 1. Inflow and recirculate.

  In such a heat exchanger, the refrigerant flow rate of the expansion device varies depending on how the degree of subcooling of the outdoor heat exchanger is increased, and the refrigerant flow rate characteristic due to the change in the enthalpy difference between the inlet and outlet of the evaporator is affected. As a result, the overall efficiency of the system, such as the cooling performance coefficient COP, will be affected, and it will affect the liquid compression prevention depending on how the superheat degree of the compressor inlet is increased. It affects the temperature rise on the inlet side of the aircraft and greatly affects the performance during high-speed operation.

  Hereinafter, related technologies for the above-described heat exchanger will be described.

  FIG. 6 is a view showing an example of a general liquid / gas heat exchanger.

  Referring to FIG. 6, in the liquid / gas heat exchanger 2, an inner first tube 11 and an outer second tube 12 are coupled in a double tube form, and one side of the first tube 11 is an evaporator side 13. The other side is connected to the inlet P2 of the compressor side 14 and is connected to the inlet P2 of the compressor side 14 so that a low-temperature and low-pressure gas flows in, exchanges heat with the fluid flowing in the second tube 12, and transfers to the compressor.

  That is, the first tube 11 is a pipe through which a low-temperature and low-pressure gas flows connected to the evaporator-side outlet P1 and the compressor-side inlet P2, and the second tube 12 is connected to the outlet P3 on the condenser side 15 and the expansion valve side 16. A medium-temperature high-pressure liquid flows as a counter flow (or a parallel flow) with the refrigerant flowing through the first tube 11 connected to the inlet P4, so that the gas flowing through the first tube 11 is brought to an intermediate temperature by heat transfer.

  7 and 8 show an embodiment of a general liquid / gas heat exchanger 2.

  As shown in FIGS. 7 and 8, radially formed cores 17 are inserted into the internal space 11 a of the first tube 11 in order to exchange heat with the refrigerant flowing through the internal first tube 11.

  The core 17 inserted into the first tube 11 has a radial shape, that is, a plurality of pins protrude perpendicularly with a certain angle from the center.

  However, since the pins of the core 17 are only in line contact with the inner peripheral surface of the first tube 11, the heat transfer performance is low and it is difficult to manufacture the core.

  Further, a medium-temperature and high-pressure liquid flows in the internal space 12 a of the second tube 12.

  FIG. 9 is a view showing another embodiment of a general liquid / gas heat exchanger 2.

  As shown in FIG. 9, the tube shape between the first tube 71 and the second tube 12 is processed into a wave shape “˜” 18, and the fluid flowing through the second tube 12 and the refrigerant flowing through the first tube 11 The efficiency of heat exchange is further improved. The other reference numbers in FIG. 9 correspond to the reference numbers in FIG.

  However, the method as shown in FIG. 9 also has a problem of low heat transfer performance.

  An object of the present invention is to arrange a double pipe heat exchanger in front of the compressor inlet, arrange a refrigerant flow switching device between the indoor heat exchanger and the outdoor heat exchanger, and reduce the degree of subcooling of the outdoor heat exchanger. To increase the refrigerant flow rate of the expansion device by increasing the flow rate, and to provide a structure capable of improving the refrigerant flow rate by increasing the enthalpy difference between the inlet and outlet of the evaporator.

  Another object of the present invention is to increase the degree of superheat at the compressor inlet, which is advantageous for preventing liquid compression and preventing temperature rise on the compressor inlet side.

  Another object of the present invention is to provide a liquid / gas heat exchanger in which a core having a surface contact structure with the inner peripheral surface of the tube is coupled to the inner or outer tube of the liquid / gas heat exchanger. Is to provide.

  Another object of the present invention is to make a tube a double tube and to flow a fluid as a counter flow or a parallel flow, and at the same time to transfer heat from the fluid flowing in the outer or inner tube to the gas refrigerant flowing in the inner or outer tube. It is another object of the present invention to provide a liquid / gas heat exchanger in which heat transfer performance can be improved by a radial or fan-shaped core inserted into the inner or outer tube.

  Another object of the present invention is to improve the heat transfer performance by expanding the fan shape with the expansion tube at the center of the fan-shaped core so that the surface contact is brought into close contact with the tube. It is to provide a liquid / gas heat exchanger that is made possible.

  Another object of the present invention is to provide a liquid / gas heat exchanger in which an inner or outer tube is divided into at least one region in the longitudinal direction and a fan-shaped core is joined in each region in a zigzag manner. Is to provide.

  Another object of the present invention is to attach a spiral inner core having a folding surface in the first tube, and to create an outer space of the inner core by a vortex generated by the folding surface of the inner core in the first tube. An object of the present invention is to provide a heat exchanger with improved heat transfer performance so that heat exchange can easily occur with the inner peripheral surface of the first tube.

  An air conditioner having a heat exchanger and a refrigerant switching device according to the present invention includes a condenser, an evaporator, a compressor, and an air conditioner having switching means for switching a refrigerant path output from the compressor. A tube heat exchanger is placed in front of the compressor.

  Further, according to the present invention, in the air conditioner having a condenser, an evaporator, a compressor, switching means for switching a refrigerant path, and a heat exchanger disposed in front of the compressor, the refrigerant discharged from the condenser or the evaporator A check valve or a four-way valve is further arranged as a refrigerant path changing means for changing the path of the refrigerant and passing through the heat exchanger.

  According to the present invention, in the air conditioner having a condenser, an evaporator, a compressor, and a heat exchanger disposed in front of the compressor, two or more refrigerant paths are formed in the heat exchanger, and the refrigerant Means for heat transfer between the refrigerant flowing through the path form a surface contact of a certain area.

  In one embodiment of the present invention, the first tube through which the first refrigerant flows, the second tube through which the second refrigerant outside the first tube flows, and the first tube or A fan-shaped core that is in surface contact with the second tube at a constant area is provided.

  In one embodiment of the present invention, an expansion tube for increasing surface contact between the first tube or the second tube and the fan-shaped core is coupled to the central portion of the core in the longitudinal direction.

  In one embodiment of the present invention, a first tube through which the first refrigerant flows, a second tube through which the second refrigerant outside the first tube flows, and the first or second tube coupled to the first or second tube. A spiral inner core that forms a line contact or a surface contact that contacts the inner peripheral surface of the two tubes at a certain area or more is provided.

  According to the present invention, the refrigerant flow rate of the expansion device is increased by increasing the degree of supercooling of the outdoor heat exchanger, and the refrigerant flow rate characteristic is improved by increasing the enthalpy difference between the inlet and outlet of the evaporator. Not only is the overall efficiency improved, it is advantageous for preventing liquid compression by increasing the degree of superheat at the compressor inlet, and it has the effect of exhibiting outstanding performance for high speed operation by preventing temperature rise on the compressor inlet side. .

  The heat exchanger according to the present invention has a heat transfer performance of a refrigerant that flows as a liquid / gas through surface contact with the tube surface by coupling a fan-shaped core that is easy to manufacture inside the tube through which the gas refrigerant flows. There is an effect that can be improved.

  In addition, the present invention expands the core by inserting and connecting an expansion tube to the core center so that the core can be brought into close contact with the tube surface, and also improves the heat transfer performance by the expansion tube There is.

  Further, the present invention has an effect of promoting heat transfer by promoting the generation of vortex using the inner core having the folding surface so that the working fluid itself frequently hits the tube wall.

  Hereinafter, preferred embodiments of an air conditioner having a heat exchanger and refrigerant switching means according to the present invention will be described with reference to the accompanying drawings.

  FIG. 10 is a block diagram showing a main configuration when a heat exchanger according to the present invention and a check valve as a refrigerant switching device are used. FIG. 11 is a four-way valve instead of a check valve for refrigerant switching in FIG. FIG. 12 is a configuration diagram showing a configuration of a heat exchange device in which the check valve and the four-way valve are not arranged in FIGS. 10 and 11.

  Referring to these drawings, in a cooling / heating device formed by an indoor heat exchanger, an outdoor heat exchanger, a four-way valve, and a compressor for compressing refrigerant, a double-tube heat exchanger 103 is provided before the inlet of the compressor 101. In addition, the refrigerant flow switching devices 106 and 107 are arranged between the indoor heat exchanger 104 and the outdoor heat exchanger 102 to perform effective heat exchange during the cooling and heating operation, and even during the cooling and heating operation switching, The refrigerant flow direction at the inlet and outlet of the double-pipe heat exchanger 103 is kept constant.

  The air conditioning apparatus of FIG. 10 is characterized in that a check valve 106 including a plurality of valves is arranged as a refrigerant flow switching device, and in another embodiment according to FIG. The valve 107 is characteristic.

  The operation of the air conditioning apparatus including the double pipe heat exchanger 103 and the refrigerant flow switching device will be described.

  During cooling, heat exchange between the medium-temperature and high-pressure liquid refrigerant on the condenser outlet side and the low-temperature and low-pressure superheated refrigerant on the evaporator outlet side increases the degree of supercooling of the liquid refrigerant on the condenser outlet side. The refrigerant flow rate characteristics are improved.

  That is, as the degree of supercooling increases, the refrigerant flow rate increases, the enthalpy on the evaporator inlet side decreases, the enthalpy difference between the inlet and outlet of the evaporator increases, and the cooling capacity increases.

  Also, during heating, heat exchange occurs between the medium-temperature and high-pressure liquid refrigerant on the condenser outlet side and the low-temperature and low-pressure superheated refrigerant on the evaporator outlet side, thereby increasing the degree of superheat on the compressor inlet side and generating liquid compression. As the possibility decreases, the operational reliability of the compressor is improved.

  That is, the heat at the evaporator inlet side and the superheated refrigerant at the evaporator outlet side are heat-exchanged to reduce the degree of superheat at the compressor inlet, that is, the evaporator outlet temperature, thereby improving the compression characteristics of the compressor. However, the compressor outlet temperature is prevented from being overheated by reducing the degree of superheat of the compressor at the time of high frequency (Hz) operation.

  FIG. 12 is a configuration diagram showing a configuration in which no check valve or four-way valve is arranged in FIGS. 10 and 11.

  As can be seen in the drawing, by installing a double-pipe heat exchanger between the four-way valve and the compressor inlet side, the medium-temperature high-pressure liquid refrigerant on the condenser outlet side and the low-temperature low-pressure superheat on the evaporator outlet side By exchanging heat with the refrigerant in the state, the degree of supercooling of the liquid refrigerant on the outlet side of the condenser is increased, and the refrigerant flow characteristic of the expansion device is improved.

  That is, as the degree of supercooling increases, the refrigerant flow rate increases, the enthalpy on the evaporator inlet side decreases, and the cooling capacity that is the enthalpy difference between the inlet and outlet of the evaporator increases.

  However, the structure of FIG. 12 is simple, but unlike the cooling mode, there is almost no heat exchange effect in the heating mode.

  13 is a perspective view of a liquid / gas heat exchanger according to an embodiment of the present invention, FIG. 14 is an exploded view of the liquid / gas heat exchanger according to an embodiment of the present invention, and FIG. FIG. 16 is a drawing in the middle of assembly of the heat exchanger in one embodiment of the invention, FIG. 16 is a cross-sectional view of the liquid / gas heat exchanger in one embodiment of the present invention, and FIGS. It is drawing which showed the liquid and gas heat exchanger in other embodiment of invention, respectively.

  Referring to FIGS. 13 to 16, a first tube 108 having inlets and outlets 111 and 110 through which a low-temperature and low-pressure gas refrigerant flows, and an outer side of the first tube 108 having inlets and outlets 113 and 112. A second tube 109 in which a medium-temperature and high-pressure liquid refrigerant flows in an opposing manner for heat transfer between the gas refrigerant flowing through the first tube 108 and the fan-shaped core housed in the first tube 108 130 and an expansion tube 114 inserted into the center of the core 130 so that the outer end of the core 130 is in close contact with the inner peripheral surface of the first tube 108.

  Here, the extension tube 114 is integrally coupled with the core 130 by processing the jaws 119 at both ends.

  The liquid / gas heat exchanger configured as described above according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  First, referring to FIGS. 13, 14 and 15, the first tube 108 which is an inner tube and the second tube 109 which is an outer tube are coupled in the longitudinal direction in a double tube form, and the first tube 108 is evaporated. The low-temperature and low-pressure gas refrigerant that is connected to the outlet P1 on the compressor side 110 and is discharged from the evaporator is subjected to heat exchange and then sent to the inlet P2 on the connected compressor side 111.

  At this time, the gaseous refrigerant is transferred from the medium-temperature and high-pressure fluid flowing in the second tube 109 in a counterflow or a parallel flow through the core formed in the first tube 108, and the gas temperature inside the first tube 108 is increased. To increase the pressure.

  In order to improve the heat transfer performance of the first tube 108, heat transfer means partially contacts the inner space 110 of the first tube 108 in the longitudinal direction. In the embodiment, the fan-shaped core 130 is configured.

  As shown in FIGS. 14, 15 and 16, the core 130 has a fan shape, and the vertical sides and the long horizontal sides 118 and 117 are connected to each other in an inverted triangular structure to form a fan shape.

  That is, the core 130 has an integrated structure in which the upper horizontal side 117 and the lower horizontal short side 116 are continuously connected to the vertical side 118 in a zigzag manner to connect the adjacent vertical sides 118. The lateral long side 117 at the end spreads in a fan shape with reference to the lateral short side 116.

  At this time, the horizontal long side 117 at the end of the core can be in surface contact with the inner peripheral surface of the first tube 108 to improve the heat transfer performance of the gaseous refrigerant.

  In addition, since the end 130 of the core 130 is in close contact with the inner peripheral surface of the first tube 108, the expansion tube 114 that penetrates the inside of the side short side 116 at the center of the core 130 is coupled in the longitudinal direction. .

  As shown in FIGS. 14 to 16, the expansion tube 114 is inserted and coupled in the longitudinal direction to the central portion of the fan-shaped core 130 coupled to the internal space 110 of the first tube 108.

  When the expansion tube is inserted into the core, the center portion of the core is expanded by the insertion of the expansion tube, so that the entire core is pressed toward the outside of the first tube 108 and the lateral long side 117 is in close contact with the inner surface of the tube. It comes in surface contact in the state.

  Such an expansion tube 114 is preferably open inside, and its radius is preferably larger than the radius formed by the lateral short side 116 at the center of the core.

  Therefore, in the first tube 108, the expansion tube 114, the fan-shaped core 130, and the inner surface of the first tube 108 are in close contact with each other.

  In this embodiment, the expansion tube 114 may have a tubular shape in the longitudinal direction, or may have another structure in which the core can be expanded in the outward direction by opening the inside.

  As shown in FIG. 16, both ends of the expansion tube 114 are processed so that a jaw portion 119 protrudes outward. The jaw portion 119 is hooked on both ends of the lateral short side 116 of the core 130. The core 130 and the expansion tube 114 are fixed together.

  Here, the cores are coupled in a structure in which the jaw portions 119 at both ends of the expansion tube 114 are projected.

  In another embodiment, a plurality of expansion tubes having a screw in the center can be coupled to the jaw, and the jaws at both ends are formed with a hammer or the like after the expansion tube is coupled, or between the jaw and the lateral short side. It is also possible to form the jaws in a spaced shape so as to be inserted into the groove.

  FIG. 17 shows a liquid / gas heat exchanger 200 according to another embodiment of the present invention.

  Referring to FIG. 17, the first tube 109 is divided into three regions d1, d2, and d3, and fan-shaped cores 130, 120, and 121 are fitted into the regions so as to fit the size of each region.

  This is efficient when it is difficult to insert a single core in the longitudinal direction.

  At this time, the three cores 130, 120, and 121 are alternately coupled in a zigzag manner in the direction in which the refrigerant flows, thereby increasing the contact area with the refrigerant, that is, the resistance, by the core vertical sides.

  One or more expansion tubes 114 are coupled to the center of the three cores 130, 120, and 121 according to the above-described method, and the fan-shaped cores 130, 120, and 121 are expanded to the outside. The surface contact is made in close contact with the inner peripheral surface of one tube 108.

  In one embodiment, the first core 121, the second core 120, and the third core 130 are coupled in a zigzag manner within the first tube 108, and a single expansion tube 114 is inserted therein.

  As a result, the gaseous refrigerant passing through the first tube 121 is heated by the fluid in the second tube 120, the first core 130, the second core 120, the third core 121, and the expansion tube 114, thereby increasing the pressure.

  In another embodiment, the present invention may have various shapes so that at least one fan-shaped core can be coupled to the first tube with at least one tube or without a tube. Structural changes are possible.

  FIG. 18 is a diagram showing a wave-shaped radial configuration as a modification of the radial core shown in FIG.

  As shown in the drawing, the low-temperature and low-pressure fluid flowing through the first tube is increased in resistance by the corrugated core to form a vortex and the heat conduction efficiency with the high-temperature and high-pressure fluid in the second tube is increased. To do.

  FIG. 19 is a view illustrating that the core 130 disposed in the first tube for heat transfer illustrated in FIG. 14 is disposed as the core 123 in the second tube. The present invention can also be applied to a core disposed on a tube.

  20 is a cross-sectional side view schematically showing a configuration of a liquid / gas heat exchanger according to another embodiment of the present invention. FIGS. 21 and 22 are exploded perspective views of the liquid / gas heat exchanger of FIG. FIG.

  As shown in the drawing, the liquid / gas heat exchanger 102 has an inner first tube 108 and an outer second tube 109 coupled in a double tube form, and the first tube 108 in the second tube 109 is one side. One side is connected to the evaporator outlet 110, and the other side is connected to the compressor inlet 111. The low-temperature and low-pressure gas is sucked and exchanged with the fluid flowing in the second tube 109 and transferred to the compressor.

  Here, the first tube 108 is connected to the evaporator outlet and the compressor inlet, and the low-temperature and low-pressure gas flows. The second tube 109 outside the first tube 108 is the condenser outlet and the inlet of the expansion valve. The gas flowing through the first tube 108 is brought to an intermediate temperature by heat conduction by allowing the second tube to flow a medium-temperature and high-pressure liquid in a flow opposite to or parallel to the refrigerant flowing through the first tube 108. . At this time, the spiral inner core 124 having a plurality of folding surfaces which are in line contact or surface contact with the inner peripheral surface of the first tube 108 with a certain area or more promotes the generation of eddy currents. The fluid itself frequently hits the tube wall to promote heat transfer, and heat exchange becomes more active.

  This operation will be described with reference to FIGS.

  A core 124 is formed by bending or bending so that a rectangular plate material is formed in a spiral shape having a plurality of folding surfaces, and the core 124 is in contact with the inner peripheral surface of the first tube 108 over a certain area. Install in line contact or surface contact. When a low-temperature refrigerant passes through the first tube 108, the refrigerant flowing between the inner peripheral surface of the first tube 108 and the outside of the spiral core 124 is the medium-temperature refrigerant in the second tube 109. Although the heat exchange results in an intermediate temperature, the refrigerant having the intermediate temperature collides with a plurality of folding surfaces formed on the spiral core 124 to form an eddy current, and the vortex current causes the first tube. It becomes easy to mix with the low-temperature refrigerant in 108.

  Therefore, the refrigerant in the first tube 108 also changes to a medium temperature refrigerant in a short time.

  FIG. 23 shows a ph diagram according to the present invention.

  As can be seen in the drawing, by performing a compression refrigeration cycle, the enthalpy on the compressor side B increases and the enthalpy on the expansion valve side A and evaporator side A decreases. It can be seen that the overall heat transfer performance is greatly improved.

  As described above, in order to efficiently perform heat exchange and cooling / heating, the present invention comprises a double pipe heat exchanger on the compressor inlet side, and includes an outdoor heat exchanger including a condenser and an indoor space including an evaporator. By disposing the refrigerant flow switching device between the heat exchanger, the medium-temperature and high-pressure liquid refrigerant on the condenser outlet side and the low-temperature and low-pressure superheated refrigerant on the evaporator outlet side are effectively exchanged heat during cooling operation. By increasing the superheat degree of the liquid refrigerant on the condenser outlet side, the refrigerant flow characteristics of the expansion device are improved, the enthalpy on the inlet side of the evaporator is reduced, and the enthalpy difference between the inlet and outlet of the evaporator is increased. And an air conditioner that increases cooling capacity.

  The heat exchanger described above has a double-pipe structure and performs line contact or surface contact so that the tube and the core of the heat exchanger that perform heat exchange in a counter flow or parallel flow are in contact with each other over a certain area. It is a structure that can enhance heat transfer performance.

  Although the preferred embodiments of the present invention have been described, the present invention can be used with various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same way even if the above-described embodiment is appropriately modified.

  Accordingly, the scope of the present invention is not limited by the limitations of the claims.

  The present invention is applicable to an air conditioner and a device in which a refrigeration cycle is operated.

It is drawing which showed the general refrigerating cycle. It is the state figure which showed the cooling cycle of the general air conditioner. It is the state figure which showed the heating cycle of the general air conditioner. It is the block diagram which showed the general air conditioning apparatus roughly. It is a block diagram which shows the case where a double pipe heat exchanger is applied to a general air conditioner. It is an illustration figure of a general liquid and gas heat exchanger. 1 is a liquid / gas heat exchanger according to one general embodiment. A liquid / gas heat exchanger according to a general embodiment 2 is a liquid / gas heat exchanger according to another general embodiment. It is a block diagram which shows the main structures using the heat exchanger by this invention, and a check valve as a refrigerant | coolant switching apparatus. It is a block diagram which shows the structure which applied the four-way valve instead of the check valve for refrigerant | coolant switching in FIG. It is a block diagram which shows the structure of the heat exchange apparatus in which the check valve and the four-way valve are not arrange | positioned in FIG.10 and FIG.11. 1 is a perspective view of a liquid / gas heat exchanger according to an embodiment of the present invention. 1 is an exploded view of a liquid / gas heat exchanger according to an embodiment of the present invention. It is a figure which shows the middle of the assembly of the heat exchanger by embodiment of this invention. 1 is a cross-sectional view of a liquid / gas heat exchanger according to an embodiment of the present invention. 4 is a view showing a liquid / gas heat exchanger according to another embodiment of the present invention. 4 is a view showing a liquid / gas heat exchanger according to another embodiment of the present invention. 4 is a view showing a liquid / gas heat exchanger according to another embodiment of the present invention. 4 is a view showing a liquid / gas heat exchanger according to another embodiment of the present invention. FIG. 21 is an exploded perspective view of the liquid / gas heat exchanger of FIG. 20. FIG. 21 is an exploded perspective view of the liquid / gas heat exchanger of FIG. 20. FIG. 3 is a ph diagram according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Compressor 102 Outdoor heat exchanger 103 Double pipe heat exchanger 104 Indoor heat exchanger 105 Four-way valve 106 Check valve 107 Four-way valve

Claims (22)

In an air conditioner having a condenser, an evaporator, a compressor, and switching means for switching a path of refrigerant discharged from the compressor,
An air conditioner characterized in that heat exchange means for performing heat exchange is arranged in front of the compressor.   The air conditioner according to claim 1, wherein the heat exchange means is a double pipe heat exchanger. In an air conditioner having a condenser, an evaporator, a compressor, switching means for switching a refrigerant path, and a heat exchanger disposed in front of the compressor,
An air conditioner comprising another refrigerant path changing means for changing a path of the refrigerant discharged from the condenser or the evaporator and passing through the heat exchanger.   The air conditioner according to claim 3, wherein the refrigerant path changing means is a check valve.   The air conditioner according to claim 4, wherein the check valve is composed of four combined valves.   The air conditioner according to claim 3, wherein the refrigerant path changing means is a four-way valve. In an air conditioner having a condenser, an evaporator, a compressor and a heat exchanger arranged in front of the compressor,
The air conditioner is characterized in that two or more refrigerant paths are formed in the heat exchanger, and means for heat transfer between the refrigerants flowing through the refrigerant path forms a surface contact of a certain area.   The two or more refrigerant paths are connected to the first tube or the first tube through which the first refrigerant flows, the second tube through which the second refrigerant outside the first tube flows, and the first or second tube. The air conditioner according to claim 7, further comprising means for contacting the two tubes with a constant area.   Means for making partial surface contact with the first tube or the second tube with a certain area is coupled to the first tube or the second tube in a longitudinal direction, and an inner peripheral surface of the first tube or the second tube. The air conditioner according to claim 8, further comprising a fan-shaped core that is partially in surface contact.   The air conditioner according to claim 8, wherein the fan-shaped cores have a vertical shape and a horizontal long side that are connected to each other in an inverted triangular structure to form a fan shape.   The core has an integrated structure in which the upper horizontal side and the lower horizontal short side are continuously connected to the vertical side in a zigzag manner in order to connect the adjacent vertical sides, with the horizontal short side at the center as a reference. The air conditioner according to claim 10, wherein the lateral long side of the terminal extends in a fan shape.   The air conditioner according to claim 9, wherein the first or second tube in which the fan-shaped core is arranged is divided into one or more and the fan-shaped cores are respectively installed.   The means for contacting the first tube or the second tube with a certain area is coupled in the longitudinal direction in the first or second tube and partially in surface contact with the inner peripheral surface of the first tube or the second tube. The air conditioner according to claim 8, further comprising a corrugated core.   14. The air conditioner according to claim 13, wherein the wave-shaped core forms a resistance force and a vortex in the refrigerant flow to increase heat conduction efficiency.   The expansion tube for increasing the surface contact between the first tube or the second tube and the fan-shaped core is coupled to the central portion of the core in the longitudinal direction. The air conditioner described in 1.   The air conditioner according to claim 15, wherein jaws that are hung on both ends of the core protrude from both ends of the expansion pipe.   The air conditioner according to claim 9, wherein two or more of the cores are disposed in the first tube or the second tube.   The air conditioner according to claim 17, wherein the two or more cores are coupled in a zigzag manner inside the first tube or the second tube.   The means for contacting the first tube or the second tube with a certain area is coupled to the first tube or the second tube in a longitudinal direction so that the inner surface of the first tube or the second tube is larger than the certain area. The air conditioner according to claim 8, further comprising a spiral inner core that makes line contact or surface contact.   The air conditioner according to claim 19, wherein the inner core includes a plurality of folding surfaces.   The air conditioner according to claim 20, wherein the plurality of folding surfaces are integrally formed by bending or bending.   21. The air conditioner according to claim 20, wherein a resistance force and a vortex flow are formed in the flow of the refrigerant by the core including the plurality of folding surfaces to increase heat conduction efficiency.

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