JP6197746B2 - Heat exchanger - Google Patents

Description

  The present invention relates to a heat exchanger.

  A heat exchanger used as a part of a heat pump system exchanges heat between refrigerant and air by flowing a refrigerant inside a plurality of tubes and flowing air outside. During the heating operation, the heat exchanger functions as an evaporator for recovering heat from the air. At this time, the temperature of the refrigerant flowing inside the tube is lower than the temperature of the air (outside temperature).

  When the surface temperature of the tube is equal to or lower than the dew point of the air, if the air touches the surface of the tube, the water in the air condenses and becomes frost as it is and adheres to the surface of the tube. In addition, fins for efficiently exchanging heat with air are often disposed between the tubes, but frost also adheres to the surfaces of the fins.

  Such a phenomenon (frost formation) is particularly likely to occur in a portion where the air first comes into contact with the tubes and fins, that is, a portion on the upstream side along the air flow direction. For this reason, the tubes and fins arranged in a row may be entirely covered with plate-like frost from the upstream side of the air. In such a state, the passage of air is hindered by frost, and heat exchange with air cannot be performed.

  In order to prevent such a phenomenon, in the heat exchanger described in Patent Document 1 below, the first tube through which the low temperature first fluid flows and the second tube through which the high temperature second fluid flows are alternately arranged. It has a configuration. The first tubes to which frost is likely to adhere are arranged apart from each other, and the second tube to which frost is unlikely to adhere is disposed between them, so that the entire flow path through which air passes is blocked. It is suppressed that frost grows until it becomes.

JP 2012-225638 A

  However, the heat exchanger described in Patent Document 1 includes a flow path through which the first fluid and a flow path through which the second fluid flows in a tank to which both the first tube and the second tube are connected. Since it is necessary to form separately, the structure is very complicated. For this reason, the assembling work of the heat exchanger becomes complicated, and the number of processes increases due to an increase in the number of brazing points.

  This invention is made | formed in view of such a subject, The objective is providing the heat exchanger which can suppress with the simple structure that the distribution | circulation of air is prevented by frost formation. It is in.

In order to solve the above-described problem, a heat exchanger according to the present invention is a heat exchanger that functions as an evaporator through which a refrigerant having a temperature lower than the outside air temperature passes, and the inside of which is the first fluid that is the refrigerant. Are arranged in the flow of air to constitute a heat exchanging portion, and tubes (130, 140 having ends (132, 142, 142F) which are upstream ends in the first direction in which the air flows). , 140E, 140F) and the upstream side in the first direction with respect to the tube, the temperature is higher than that of the tube, and at least a part of the end portion (142, 142F) And a blockage suppression unit (230, 230C, 230D, 240) provided with a receiving unit (241) for entering.

  In the present invention, a clogging suppression portion having a temperature higher than that of the end portion is disposed in the vicinity of the end portion, which is the portion where the frost is most likely to adhere to the tube. For this reason, frost adhesion and growth can be further suppressed. In addition, since the blockage suppressing portion is provided with a receiving portion into which at least a part of the end portion enters, the temperature between the end portions can be increased, and frost generated at one end portion and other The adhesion and growth of frost that connects frost generated at the end of the frost can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the heat exchanger which can suppress that the distribution | circulation of air is prevented by frost formation with a simple structure.

It is a figure which shows the whole structure of the heat pump system and cooling system containing the heat exchanger which concern on 1st Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger shown in FIG. It is a figure for demonstrating the flow of the fluid in the heat exchanger shown in FIG. It is a perspective view which shows the shape of a corrugated fin among the heat exchangers shown in FIG. It is a figure which shows the AA cross section in FIG. It is a figure which shows the BB cross section in FIG. It is a schematic diagram for demonstrating the frost produced in a heat exchanger. It is a schematic diagram for demonstrating the frost produced in a heat exchanger. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 2nd Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 3rd Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 4th Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 5th Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 6th Embodiment of this invention. It is a figure which shows CC cross section in FIG. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 7th Embodiment of this invention. It is a perspective view which shows typically the structure of the heat exchanger which concerns on 8th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  As shown in FIG. 1, the heat exchanger 10 according to the first embodiment of the present invention is a part of a heat pump system 20 configured as an air conditioner for a vehicle, and includes a cooling system 60 for the vehicle. It is also part. The heat pump system 20 includes a heat exchanger 10, an indoor condenser 201, and an indoor evaporator 211, and constitutes a heat pump cycle. The heat pump system 20 absorbs heat from the air outside the vehicle to the refrigerant, compresses the refrigerant by the compressor 43, and further raises the temperature of the refrigerant, thereby heating the vehicle interior and heating the vehicle interior. And the cooling operation in which the refrigerant absorbs heat and releases the heat to the outside of the vehicle.

  The indoor condenser 201 and the indoor evaporator 211 are arranged in the casing 31 of the air conditioning unit 30. A refrigerant (first fluid) is circulated between the indoor condenser 201 and the indoor evaporator 211 and the heat exchanger 10. As will be described in detail later, during the heating operation, the refrigerant circulates between the heat exchanger 10 and the indoor condenser 201, and the heat recovered from the outside air in the heat exchanger 10 and the compression operation of the compressor 43. Heat from the refrigerant whose temperature has risen is released from the indoor condenser 201 and air into the casing 31. Further, during the cooling operation, the refrigerant circulates between the heat exchanger 10 and the indoor evaporator 211, and the heat of the air in the casing 31 collected in the indoor evaporator 211 is transferred from the heat exchanger 10 to the outside air. Released.

  The casing 31 is a duct for supplying air heated or cooled by heat exchange into the vehicle interior. A blower 32 and an inside / outside air switching device 33 are arranged in an upstream portion of the casing 31. The blower 32 is a fan for sending the air in the casing 31 toward the vehicle interior. The inside / outside air switching device 33 is a switching valve for switching between an outside air circulation state where air outside the vehicle is supplied into the casing 31 and an inside air circulation state where air inside the vehicle interior is supplied again into the casing 31. The rotation of the blower 32 and the operation of the inside / outside air switching device 33 are controlled by the control device 100.

  An indoor evaporator 211 is arranged on the upstream side and an indoor condenser 201 is arranged on the downstream side along the air flow direction in the casing 31. An air mix door 34 is disposed between the indoor evaporator 211 and the indoor condenser 201. The air mix door 34 is a flow rate adjustment valve for adjusting the amount of air that passes through the indoor condenser 201 out of the air flowing in the casing 31, that is, the amount of air that is heated and travels toward the vehicle interior. When the opening degree of the air mix door 34 is changed by the control device 100, the temperature of the air supplied into the vehicle interior is adjusted.

  The heating operation will be described. During the heating operation, the refrigerant passes through the pipe connecting the heat exchanger 10, the three-way valve 41, the accumulator 42, the compressor 43, the indoor condenser 201, and the fixed throttle 44 in order to return to the heat exchanger 10. Circulate. Such refrigerant circulation is performed by the compressor 43 serving as a pump sending out the refrigerant toward the indoor condenser 201.

  The fixed throttle 44 is an orifice for decompressing and expanding the passing refrigerant. The refrigerant sent out by the compressor 43 is compressed between the compressor 43 and the fixed throttle 44 and changes (condenses) from the gas phase to the liquid phase in the indoor condenser 201. At this time, the air that passes through the indoor condenser 201 in the casing 31 is heated by the high temperature of the compressed refrigerant.

  The refrigerant that has passed through the fixed throttle 44 reaches the heat exchanger 10 in a state where its temperature is reduced to a temperature lower than the outside air temperature by expanding under reduced pressure. Air from the outside of the vehicle (outside air) is supplied to the heat exchanger 10 by the blower fan 50. In the heat exchanger 10, heat exchange is performed between the supplied air and the refrigerant, and the heat of the air is recovered by the refrigerant. The refrigerant increases its enthalpy by heat exchange with air, and changes from the liquid phase to the gas phase inside the heat exchanger 10. That is, during the heating operation, the heat exchanger 10 functions as an evaporator. The specific structure of the heat exchanger 10 will be described in detail later.

  The refrigerant that has passed through the heat exchanger 10 returns to the compressor 43 through the accumulator 42 and is sent out from the compressor 43 toward the indoor condenser 201 again. The accumulator 42 collects the refrigerant (liquid) when a part of the refrigerant passing through is in a liquid phase. By passing such an accumulator 42, so-called liquid compression is prevented from occurring in the compressor 43.

  Subsequently, the cooling operation will be described. During the cooling operation, the refrigerant passes through the heat exchanger 10, the three-way valve 41, the fixed throttle 45, the indoor evaporator 211, the accumulator 42, the compressor 43, the indoor condenser 201, and the bypass channel 46 in order. It circulates in the pipe which connects these so that it may return. In other words, the state of the three-way valve 41 and the state of the on-off valve 47 provided in the bypass flow path are switched by the control device 100 so that the refrigerant circulates in such a path. Similar to the heating operation, the refrigerant is circulated by the compressor 43 serving as a pump sending the refrigerant toward the indoor condenser 201.

  The bypass channel 46 is a channel that bypasses the fixed throttle 44. During the cooling operation, the on-off valve 47 is opened, and most of the refrigerant reaches the heat exchanger 10 through the bypass channel 46. For this reason, the refrigerant is not decompressed and expanded at the fixed throttle 44 during the cooling operation.

  The fixed throttle 45 is an orifice having the same configuration as the fixed throttle 44 and is disposed between the three-way valve 41 and the indoor evaporator 211. The refrigerant sent out by the compressor 43 is compressed between the compressor 43 and the fixed throttle 45 and changes (condenses) from the gas phase to the liquid phase in or near the heat exchanger 10. When the compressed refrigerant reaches a high temperature, air from outside the vehicle passing through the heat exchanger 10 is heated. Moreover, the heat exchanger 10 performs heat dissipation from the refrigerant to the air, so that the temperature of the refrigerant passing through the heat exchanger 10 is lowered.

  The refrigerant that has passed through the fixed throttle 45 reaches the indoor evaporator 211 in a state where its temperature is reduced by expanding under reduced pressure. Air is supplied to the indoor evaporator 211 by the blower 32. In the indoor evaporator 211, heat exchange is performed between the air and the refrigerant, and the air passing through the indoor evaporator 211 is cooled. On the other hand, the refrigerant passing through the indoor evaporator 211 increases its enthalpy and changes from the liquid phase to the gas phase inside the indoor evaporator 211.

  The refrigerant that has passed through the indoor evaporator 211 returns to the compressor 43 through the accumulator 42 and is sent out from the compressor 43 toward the indoor condenser 201 again. The function of the accumulator 42 at this time is the same as the function during the heating operation already described.

  As described above, the heat exchanger 10 is a part of the heat pump system 20, but is also a part of the vehicle cooling system 60 in the present embodiment. The cooling system 60 includes a cooling target 61 made of an engine or the like that becomes high temperature, a pump 62, a water temperature sensor 63, a bypass flow path 64, and a three-way valve 65. The heat exchanger 10 is disposed in a path of cooling water (second fluid) that circulates these.

  As the pump 62 operates, the cooling water circulates between the object to be cooled 61 and the heat exchanger 10. The heat exchanger 10 is supplied with cooling water that has passed the cooling target 61 and has reached a high temperature. In the heat exchanger 10, heat exchange between the air from the outside of the vehicle supplied by the blower fan 50 and the high-temperature cooling water is performed, and the temperature of the passing cooling water decreases. That is, the heat exchanger 10 is a composite heat exchanger that also functions as a radiator for cooling the object 61 to be cooled.

  When the water temperature sensor 63 detects that the temperature of the circulating cooling water has decreased, the control device 100 switches the flow path using the three-way valve 65 so that the cooling water bypasses the heat exchanger 10 and passes through the bypass flow path 64. Let it flow. Since the cooling water is not cooled by the heat exchanger 10, the temperature gradually increases. When the temperature of the cooling water exceeds a predetermined threshold, the control device 100 switches the flow path again by the three-way valve 65 so that the cooling water flows through the heat exchanger 10. By such switching of the flow path, the temperature of the cooling water circulating in the cooling system 60 is kept within a certain range.

  A specific configuration of the heat exchanger 10 will be described with reference to FIGS. 2, 3, 5, and 6. The heat exchanger 10 includes a pair of tanks 110 and 120 (not shown in FIG. 2, not shown in FIG. 5), and a plurality of first tubes 130 and second tubes 140 disposed therebetween. . Each of the tanks 110 and 120 is a cylindrical tank that stores therein the refrigerant circulating in the heat pump system 20, and the tanks 110 and 120 are arranged so as to be parallel to each other with the longitudinal direction thereof being along the vertical direction. Yes. 2 and 3, the flow direction of air supplied to the heat exchanger 10 by the blower fan 50 (hereinafter also referred to as “first direction”) is indicated by an arrow AR1. In the present embodiment, the air flow direction is a horizontal direction and a direction perpendicular to both the longitudinal direction of the first tube 130 and the longitudinal direction of the second tube 140.

  The first tube 130 is a tube having a flat cross section and having a plurality of flow paths 131 along the longitudinal direction formed therein. Both the upper surface and the lower surface of the first tube 130 are parallel to the horizontal plane. That is, it is a surface along the first direction. The 1st tube 130 is arrange | positioned so that the tank 110 and the tank 120 may be connected in the state which followed the horizontal direction in the longitudinal direction. As shown in FIG. 6, the inside of the tank 110 and the inside of the tank 120 are communicated by a flow path 131 in the first tube 130. For this reason, the refrigerant can flow from the tank 110 to the tank 120 (or in the opposite direction) through the first tube 130. The 1st tube 130 functions as a heat exchange part by which heat exchange with the refrigerant | coolant and air which flow through an inside is arrange | positioned in the flow of the air along a 1st direction.

  The overall shape of the heat exchanger 10 is substantially symmetrical with a plane (symmetric plane) passing through the central portion of the first tube 130 in the longitudinal direction and perpendicular to the longitudinal direction. For this reason, in FIG. 2, only the portion closer to the tank 110 than the symmetry plane is depicted, and the portion closer to the tank 120 is not shown.

  Similar to the first tube 130, the second tube 140 has a flat cross section, and a plurality of flow paths 141 along the longitudinal direction are formed inside. The upper surface and the lower surface of the second tube 140 are both parallel to the horizontal plane. That is, it is a surface along the first direction. The 2nd tube 140 is arrange | positioned so that the tank 110 and the tank 120 may be connected in the state which followed the horizontal direction in the longitudinal direction. As shown in FIG. 5, the inside of the tank 110 and the inside of the tank 120 are also communicated by a flow path 141 in the second tube 140. The 2nd tube 140 functions as a heat exchange part by which heat exchange with the refrigerant | coolant and air which flow through an inside is arrange | positioned in the flow of the air along a 1st direction.

  The dimension of the second tube 140 in the width direction (the horizontal direction and the direction perpendicular to the longitudinal direction of the second tube 140) is longer than the dimension of the first tube 130 in the width direction. A second end 142 that is an upstream end in the first direction of the second tube 140 is further upstream than a first end 132 that is an upstream end in the first direction of the first tube 130 ( (y direction side) is arranged.

  In FIG. 2, the x axis is set with the horizontal direction and the direction from the tank 120 toward the tank 110 as the x direction. Further, the y axis is set with the direction opposite to the first direction indicated by the arrow AR1 as the y direction. Further, the z-axis is set with the direction going vertically upward as the z direction. In the subsequent drawings, the x axis, the y axis, and the z axis are similarly set.

  As shown in FIG. 2, a plurality of first tubes 130 and a plurality of second tubes 140 are provided, and these tubes are alternately arranged along the z direction (direction intersecting the first direction). . Further, corrugated fins 150 are disposed along the x direction between the first tube 130 and the second tube. As shown in FIG. 4, the corrugated fin 150 connects the plurality of flat plate portions 151 parallel to each other, the bent portion 152 connecting the upper end portions of the adjacent flat plate portions 151, and the lower end portions of the adjacent flat plate portions 151. A metal plate formed to have a bent portion 153. The flat plate portion 151 is provided such that the normal direction is along the x direction. The upper end of the bent portion 152 and the lower end of the bent portion 153 are fixed to the surface of the first tube 130 or the second tube 140 in the vicinity by brazing. For this reason, the heat from the first tube 130 and the like is not only directly transmitted to the air passing through the heat exchanger 10 but also transmitted to the air via the corrugated fins 150. That is, the corrugated fin 150 increases the contact area with air, and heat exchange between the refrigerant and air is performed efficiently.

  As shown in FIG. 3, one space is formed inside the tank 110, while two spaces are formed inside the tank 120. Specifically, a partition plate 121, which is a horizontal flat plate, is disposed at the center portion in the z direction of the tank 120, and the partition plate 121 allows the space inside the tank 120 to be separated from the upstream space 122 and the downstream side. It is divided into a space 123.

  The upstream space 122 is a space below the partition plate 121 and has an inlet portion 124 that is an inlet for the refrigerant. A pipe on the downstream side of the fixed throttle 44 and the bypass passage 46 shown in FIG. 1 is connected to the inlet 124 (not shown in FIG. 3).

  The downstream space 123 is a space above the partition plate 121 and has an outlet 125 that is an outlet for the refrigerant. A pipe extending to the three-way valve 41 shown in FIG. 1 is connected to the outlet 125 (not shown in FIG. 3).

  The refrigerant that has flowed from the fixed throttle 44 or the bypass channel 46 toward the heat exchanger 10 flows into the upstream space 122 from the inlet portion 124 as indicated by arrows in FIG. Thereafter, the refrigerant passes through the flow path 131 of the first tube 130 and the flow path 141 of the second tube 140 and flows into the tank 110. Further, the refrigerant flows upward in the tank 110, and then flows into the downstream space 123 through the flow path 131 of the first tube 130 and the flow path 141 of the second tube 140, and the outlet portion 125. Is discharged to the three-way valve 41. The refrigerant absorbs or dissipates heat by exchanging heat with the air passing between the corrugated fins 150 while flowing in the heat exchanger 10 as described above.

  The description will be continued with reference to FIG. The heat exchanger 10 further includes a pair of tanks 210 and 220 (not shown in FIG. 2, not shown in FIG. 5), a plurality of water flow tubes 230 disposed therebetween, and a plurality of plate fins 240. I have. Both of the tanks 210 and 220 are cylindrical tanks that store therein cooling water circulating through the cooling system 60, and are arranged so as to be parallel to each other with the longitudinal direction thereof being along the vertical direction. ing.

  The water flow tube 230 is disposed so as to connect the tank 210 and the tank 220 substantially along the x direction. As shown in FIG. 6, the inside of the tank 210 and the inside of the tank 220 are communicated with each other by a water flow tube 230. For this reason, the cooling water can pass from the tank 210 to the tank 220 (or in the opposite direction) through the water flow tube 230.

  As shown in FIG. 2, a plurality of water flow tubes 230 are provided and are arranged along the z direction in parallel with each other. Moreover, the flow path cross section of each water flow tube 230 is elliptical, and the major axis direction of the elliptical shape is the direction along the y-axis.

  The plate fins 240 are rectangular plates made of metal, and the thickness direction thereof is arranged along the x direction, and the longitudinal direction thereof is arranged along the z direction. Each plate fin 240 has the same shape, and a plurality of plate fins 240 are arranged along the x direction. As a result of the arrangement of the plate fins 240, the plate fins 240 are close to both the first tube 130 and the second tube 140.

  Each of the water flow tubes 230 passes through all the plate fins 240 along the x direction, and is fixed to the plate fins 240 by brazing at the through portions. As shown in FIG. 2, the position where the water passage tube 230 passes through the plate fin 240 is a position that is substantially the center of the plate fin 240 in the y direction and is the same height as the first tube 130. It is. When cooling water flows through the water flow tube 230, each plate fin 240 is heated or cooled by the cooling water.

  As shown in FIG. 3, one space is formed inside the tank 210, while two spaces are formed inside the tank 220. Specifically, a partition plate 221, which is a horizontal flat plate, is disposed at the center in the z direction of the tank 220, and the partition plate 221 divides the internal space between the upstream space 222 and the downstream space 223. It is divided into.

  The upstream space 222 is a space below the partition plate 221 and has an inlet 224 that is an inlet of cooling water. A pipe on the downstream side of the cooling target 61 shown in FIG. 1 is connected to the inlet 224.

  The downstream space 223 is a space above the partition plate 221 and has an outlet 225 that is an outlet of the cooling water. A pipe extending to the three-way valve 65 shown in FIG. 1 is connected to the outlet portion 225.

  As indicated by arrows in FIG. 3, the cooling water that has flowed from the object to be cooled 61 toward the heat exchanger 10 flows into the upstream space 222 from the inlet portion 224. Thereafter, the cooling water flows into the tank 210 through the water flow tube 230. Further, the cooling water flows upward in the tank 210, then flows into the downstream space 223 through the water flow tube 230, is discharged from the outlet portion 225, and goes to the three-way valve 65. The cooling water heats or cools each plate fin 240 while flowing inside the heat exchanger 10 as described above. As a result, heat exchange between the air passing between the plurality of plate fins 240 and the cooling water is performed.

  As described above, in the present embodiment, the direction in which the refrigerant flows in the heat exchanger 10 and the direction in which the cooling water flows are substantially the same when viewed along the first direction. As a result, the temperature of the flowing refrigerant is highest during the cooling operation (the portion of the first tube 130 and the second tube 140 that is close to the inlet 124) and the temperature of the flowing cooling water is highest during the cooling operation. The portions (portions close to the inlet portion 224 of the water flow tube 230) overlap each other when viewed along the first direction. Further, a portion where the temperature of the flowing refrigerant is the lowest during the cooling operation (a portion of the first tube 130 and the second tube 140 close to the outlet 125) and a portion where the temperature of the flowing cooling water is the lowest during the cooling operation. (Portion close to the outlet portion 225 in the water flow tube 230) overlap each other when viewed along the first direction.

  With such a configuration, during the cooling operation, the air passes through the hot plate fin 240 and is heated by the first tube 130 no matter where the air passes through the heat exchanger 10. Etc., and it is heated further. That is, after the air passes through the hot plate fins 240 and is heated, the air does not pass through the first tube 130 and the like, so that the subcooled state is reliably taken in the refrigerant circulation path. It is easy to configure.

  The specific shape of the plate fin 240 will be further described with reference to FIG. A rectangular recess 241 (receiving portion) is formed in the plate fin 240 at a position having the same height as the second tube 140 so as to recede in the y direction from the second tube 140 side. The second end 142 of the second tube 140 is accommodated inside the recess 241, and the plate fin 240 and the second tube 140 partially overlap each other when viewed from above. Since it is such a structure, even if the 2nd end part 142 is arrange | positioned rather than the 1st end part 132 at the y direction side, the dimension in the y direction of the heat exchanger 10 will not enlarge by this. .

  In the present embodiment, in order to facilitate the understanding of the configuration, FIG. 2 and the like are drawn assuming that the range in which the plurality of plate fins 240 are arranged along the x direction is relatively narrow. However, in view of the heat exchange efficiency when the heat exchanger 10 functions as a radiator in the cooling system 60, it is desirable that the range in which the plate fins 240 are actually arranged be as wide as possible. Ideally, when viewed from the upstream side in the air flow direction (y direction side), the plate fins 240 are arranged so as to cover substantially the entire range in which the corrugated fins 150 are arranged, that is, the range through which air passes. It is desirable to have a configuration. The same applies to other embodiments (FIGS. 9 to 16) described later.

  The effect of arranging the second end portion 142 at a position closer to the y direction than the first end portion 132 and accommodating the second end portion 142 in the concave portion 241 of the plate fin 240 will be described. As already explained, during the heating operation of the heat pump system 20, the heat exchanger 10 functions as an evaporator. At this time, the temperature of the refrigerant passing through the heat exchanger 10 is lower than the outside air temperature and 0 ° C. or less. For this reason, when the air supplied by the blower fan 50 passes through the heat exchanger 10, the air comes into contact with the surface of the first tube 130 or the like that has become low temperature and is cooled, and moisture in the air is condensed. As a result, it becomes frost and adheres to the surfaces of the first tube 130, the second tube 140, and the corrugated fin 150.

  FIG. 7 shows that the first tube 130 and the second tube 140 of the heat exchanger 10 have the same shape, and the y coordinate of the first end 132 and the y coordinate of the second end 142 are the same. It is the figure which showed the heat exchanger 10X arrange | positioned so that it may be, Comprising: It is the figure which showed typically the state which the phenomenon (frost formation) which frost adheres as mentioned above produced. The heat exchanger 10X includes a first tube 130X, a second tube 140X, and a corrugated fin 150X. The y-coordinate of the first end 132X of the first tube 130X and the y-coordinate of the second end 142 of the second tube 140 are arranged to be substantially the same, and the plate fin 240X is arranged upstream of them. Has been. The frost formation is a portion where moisture containing air is first cooled, that is, a portion of the first tube 130X, the second tube 140X, and the corrugated fin 150X that is first touched by the air passing through each of them (air flow). It is particularly likely to occur on the upstream side in the direction and in the vicinity of the thick line BL1 in FIG.

  In FIG. 7, the first end portion 132X of the first tube 130X, the second end portion 142X of the second tube 140X, and the y-direction side end portion of the corrugated fin 150X are arranged substantially linearly along the z direction. . That is, the portions where frost formation is likely to occur (thick line BL1) are arranged almost linearly along the z-axis. For this reason, the range to which frost adheres during heating operation is like the area FA1 indicated by the oblique lines in FIG. 7, and the frost adheres so that the whole becomes a substantially flat plate shape. .

  FIG. 8 schematically shows a state in which frost formation has occurred in the actual heat exchanger 10. In the actual heat exchanger 10, among the first tube 130, the second tube 140, and the corrugated fins 150, the first contact with the air passing through each of them (in the vicinity of the thick line BL2 in FIG. 8), that is, frost formation occurs. The parts that are likely to occur are not arranged in a straight line. That is, since the second end 142 of the second tube 140 is disposed on the upstream side (y direction side) of the air flow with respect to the first end 132 of the first tube 130, the second end 142 and the first end The distance from the end 132 is separated compared to the case of FIG.

  For this reason, the range where frost begins to adhere during heating operation tends to be divided into a plurality of regions that are not connected to each other, such as a region FA2 indicated by hatching in FIG. Even if the first end 132 and the second end 142 are exposed to air and frost is generated on the first end 132 and the second end 142, they are not easily connected to each other. Therefore, in order to be in a state where the whole flow path through which air flows is covered with frost, it is necessary to generate frost that connects the first end portion 132 and the second end portion 142 that are separated from each other, and water (steam) required for the generation. The amount of increases.

  In this way, even in the heat exchanger 10X as shown in FIG. 7, even if the amount of frost that hinders the flow of air is generated in the heat exchanger 10 according to the present embodiment shown in FIG. The state where the entire flow path through which the air flows is blocked by frost (a state in which the area FA2 is connected to one) is unlikely, and the possibility that heat exchange with the air can be continued is increasing.

  Moreover, in this embodiment, the 1st tube 130 and the 2nd tube 140 are arrange | positioned in the state which was located in a line by turns along the z direction. For this reason, the area FA2 where frost begins to adhere during heating operation is easily divided into more areas, and the possibility that the entire flow path through which the air flows is blocked by frost is even lower. It has become a thing.

  The plate fins 240 are portions that dissipate into the air that passes through the heat of the cooling target 61 made of a high-temperature engine or the like. For this reason, the temperature of the cooling water flowing inside the plate fin 240 is higher than the temperature of the refrigerant flowing through the flow path 131 of the first tube 130 and the flow path 141 of the second tube 140 during the heating operation. Further, the temperature of the plate fin 240 is also higher than that of the first tube 130 or the like.

  In the heat exchanger 10, the end of the plate fin 240 on the −y direction side is close to the end of the first tube 130 on the y direction side. In addition, the plate fin 240 and the second tube 140 are close to each other on the entire surface that defines the recess 241. That is, the portions where frost is likely to be generated in the heat exchanger 10 (portions along the thick line BL2 in FIG. 8) are all close to the high-temperature plate fins 240.

  Further, as shown in FIG. 8, as a result of the concave portion 241 into which the second end portion 142 is inserted in the plate fin 240, a part of the plate fin 240 is interposed between the first end portion 132 and the second end portion 142. Since it is in a state of entering, the space between the first end portion 132 and the second end portion 142 is also heated by the plate fins 240. Thereby, it is possible to further suppress the adhesion and growth of frost that connects the frost generated at the first end portion 132 and the frost generated at the second end portion 142. As described above, the plate fin 240 has a function of suppressing the entire flow path through which air passes through the heat exchanger 10 from being blocked by frost formation, and corresponds to the blockage suppressing portion in the present invention. is there.

  In the heat exchanger 10, the plate fins 240 are not arranged side by side between the first tube 130 and the second tube 140, but are upstream of the first tube 130 and the second tube 240 in the first direction ( (y direction side). For this reason, it is not necessary to flow both the refrigerant and the cooling water into the tanks 110 and 120, and the refrigerant flow path and the cooling water flow path can be made independent. Furthermore, the 1st tube 130 and the 2nd tube 140 both flow the same refrigerant | coolant through the inside. For this reason, only one type of refrigerant needs to flow through the tanks 110 and 120 to which the first tube 130 and the second tube 140 are connected, and a flow path through which two or more types of fluids flow is formed inside the tanks 110 and 120. There is no need to provide it. As a result, the structure of the heat exchanger 10 is relatively simple and can be manufactured with a relatively small number of man-hours.

  Immediately after the heat pump system 20 is switched from the heating operation to the cooling operation, the temperature of the refrigerant becomes high, so that the attached frost becomes liquid (water) and the first tube 130 and the second tube 140 respectively. It is conceivable that it accumulates on the upper surface. However, in the heat exchanger 10, the plate fins 240 that are arranged so that the longitudinal direction is along the vertical direction are arranged close to both the first tube 130 and the second tube 140. For this reason, water easily flows downward along the plate fins 240. Thus, since the heat exchanger 10 has good drainage, the accumulated water is prevented from interfering with the air flow. In the present embodiment, the entire plate fin 240 corresponds to the “longitudinal portion” of the present invention.

  In this embodiment, the plate fin 240 which is a member for heating both the first tube 130 and the second tube 140 also functions as a member for improving drainage as described above. Thus, the member for heating and the member for improving drainage are made common, and it is not necessary to provide both as separate members. As a result, the number of parts of the heat exchanger 10 is reduced, and the structure is further simplified.

  In addition, as a structure for making drainage favorable, it is not restricted to the above. For example, the plate fin 240 has a shape having one or a plurality of longitudinal portions, and after the longitudinal portions are brought close to both the first tube 130 and the second tube 140, the extending direction of the longitudinal portions is What is necessary is just to arrange | position so that it may go to the downward from upper direction. In other words, the target in which one longitudinal portion is close may not be all the first tubes 130 and the second tubes 140 included in the heat exchanger 10. Further, the extending direction of the longitudinal portion may be a direction inclined with respect to the vertical direction.

  In the present embodiment, a plurality of flow paths 131 are formed inside the first tube 130. However, the embodiment of the present invention is not limited to such an aspect. For example, a welded tube formed by bending a single plate and welding the ends may be used as the first tube 130. That is, a tube in which a single flow path is formed may be used as the first tube 130. The same applies to the second tube 140.

  Moreover, the water flow tube 230 can use not only piping having an elliptical cross section but also piping having a circular cross section. Also, the same pipe (flat multi-hole pipe) as the first tube 130 can be used.

  In the present embodiment, the first tube 130 and the second tube 140 are arranged in a state of being alternately arranged along the z direction. The arrangement of the first tube 130 and the second tube 140 is not necessarily limited to this. That is, the arrangement may be such that the second tube 140 is arranged next to the first tube 130 in at least a part of the arrangement order. For example, the arrangement may be such that two first tubes 130 and one second tube 140 are alternately arranged along the z direction.

  In the present embodiment, the plate fin 240 functioning as a heating unit is heated to high temperature by cooling water (fluid having a temperature higher than that of the refrigerant) flowing through the water flow tube 230 and heats the first tube 130 and the second tube 140. Instead of such a mode, the plate fin 240 may be configured to be heated by another heat source. For example, an electric heater may be embedded in the plate fin 240, and the plate fin 240 may be heated by heat generated by the electric heater.

  The fluid flowing through the water flow tube 230 is not limited to cooling water, and may be a refrigerant circulating in the heat pump system 20. For example, the refrigerant between the indoor condenser 201 and the fixed throttle 44 or the refrigerant on the downstream side of the fixed throttle 44 may be first circulated through the water flow tube 230 and then circulated through the first tube 130 and the second tube 140. . In such a configuration, the refrigerant temperature in the water flow tube 230 becomes higher than the refrigerant temperatures in the first tube 130 and the second tube 140 due to internal pressure loss. Furthermore, the refrigerant on the downstream side of the water flow tube 230 may be circulated through the first tube 130 and the second tube 140 after being depressurized by pressure loss applying means such as a fixed throttle. In this case, the refrigerant temperature in the water flow tube 230 is further higher than the refrigerant temperatures in the first tube 130 and the second tube 140.

  Incidentally, as described with reference to FIG. 1, the heat exchanger 10 is a part of the heat pump system 20 configured as an air conditioner for vehicles, but the air that has passed through the heat exchanger 10. Is not directly supplied to the passenger compartment. That is, the heat exchanger 10 in this embodiment functions as an outdoor unit of an air conditioner. However, the heat exchanger 10 can be configured to be used as an indoor unit of an air conditioner.

  For example, as in the case of the cooling operation in the heat pump system 20, if a refrigerant having a temperature higher than the outside temperature is allowed to pass through the inside by using the heat exchanger 10 as a condenser, the air passes through the heat exchanger 10. It will be heated at the time. In addition, since the temperature of the cooling water is higher than that of air, the air is also heated when passing through the plate fins 240 that function as a radiator of the radiator. Therefore, the configuration may be such that the air heated through the heat exchanger 10 is directly supplied to the vehicle interior. In such a configuration, the heat exchanger 10 shown in FIG. 2 functions as an indoor unit of the vehicle air conditioner.

  In this case, only when the temperature of the cooling water and the plate fin 240 is low, for example, immediately after the engine is started, a high-temperature refrigerant is passed through the first tube 130 and the second tube 240 and used as an auxiliary heat source. May be. Further, for example, in the case where the heat generation amount of the engine is small and the temperature of the plate fin 240 is constantly low as in a hybrid vehicle, a configuration in which a high-temperature refrigerant is always passed through the first tube 130 or the like may be employed. That is, when heating the vehicle interior, the air supplied to the vehicle interior may be always heated by both the refrigerant (first fluid) and the cooling water (second fluid).

  Subsequently, a heat exchanger 10A according to a second embodiment of the present invention will be described with reference to FIG. The heat exchanger 10A is different from the heat exchanger 10 in terms of the shape of the tank 110A and the arrangement of the tank 210, but is otherwise substantially the same as the heat exchanger 10 in other configurations.

  In the present embodiment, the tank 210 is disposed at a position on the x direction side of the tank 110A. A recess 111A is formed in the surface on the y direction side of the tank 110A at a position having the same height as each of the water flow tubes 230A so as to recede from the water flow tube 230A side in the -y direction. A part of each water flow tube 230A is accommodated in the recess 111A.

  In such a configuration, the water flow tube 230A can be brought closer to the tank 110A side (the −y direction side), and therefore the size of the heat exchanger 10A along the y direction can be reduced. Further, since the tank 210 is disposed on the x direction side of the tank 110A, more plate fins 240 can be disposed on the upstream side (y direction side) of the corrugated fins 150.

  Subsequently, a heat exchanger 10B according to a third embodiment of the present invention will be described with reference to FIG. The heat exchanger 10B is different from the heat exchanger 10 in terms of the shape of the tank 210B, but is otherwise substantially the same as the heat exchanger 10 in other configurations.

  In the present embodiment, the concave portion 211 </ b> B is set so as to recede in the y direction from the second tube 140 side to a position having the same height as the second tube 140 on the −y direction side surface of the tank 210 </ b> B. Is formed. A part of each second end 142 is accommodated in the recess 211B.

  In such a configuration, since the tank 210B can be brought closer to the second tube 140 side (−y direction side), the size of the heat exchanger 10B along the y direction can be reduced.

  Next, a heat exchanger 10C according to the fourth embodiment of the present invention will be described with reference to FIG. The heat exchanger 10C is different from the heat exchanger 10 with respect to the shape of the water flow tube 230C and the arrangement of the tank 210, but the other configurations are generally the same as the heat exchanger 10.

  In the present embodiment, the tank 210 is disposed at a position on the x direction side of the tank 110. The tank 210 is connected to an end of a water flow tube 230 </ b> C that penetrates the plate fin 240. In the present embodiment, the cross-sectional shape of the water flow tube 230 </ b> C is not an elliptical shape, and is a flat shape similar to that of the first tube 130. A plurality of flow paths 231C are formed inside the water flow tube 230C.

  The water flow tube 230C penetrates each plate fin 240 in a state where the longitudinal direction of the flat cross-sectional shape is along the y direction. Further, between the plate fin 240 and the tank 210 arranged on the most x-direction side (portion denoted by reference sign P in FIG. 11), the water flow tube 230C is twisted by 90 degrees. As a result, in the portion of the water flow tube 230C on the tank 210 side (the portion facing the first tank 110 along the y direction), the longitudinal direction in the flat cross-sectional shape is in a state along the z direction. ing.

  In such a configuration, the tank 210 can be brought closer to the tank 110 side (−y direction side) while the cross-sectional shape of the water flow tube 230C is flattened, so the dimension of the heat exchanger 10C along the y direction is There will be no increase in size. Further, since the tank 210 is disposed at the position on the x direction side of the tank 110, more plate fins 240 can be disposed on the upstream side (y direction side) of the corrugated fins 150.

  Subsequently, a heat exchanger 10D according to a fifth embodiment of the present invention will be described with reference to FIG. The heat exchanger 10D is different from the heat exchanger 10 in that it does not have one tank 210 and in the shape of the water flow tube 230D, but the other configuration is generally the same as the heat exchanger 10.

  In the present embodiment, the tank 210 is not disposed further on the x direction side than the plate fin 240 disposed on the most x direction side, and only the tank 220 (not shown in FIG. 12, refer to FIG. 5). Has been placed. Since the cooling water discharged from the tank 220 is configured so as to return to the tank 220 again, each of the water flow tubes 230D has two water flow tubes 230Da arranged in the horizontal direction along the horizontal direction. The ends of each other are connected by a U-shaped pipe 230Db. That is, it is folded in a U shape at the end on the tank 110 side. As indicated by the arrows in FIG. 12, the cooling water flows in the water passage tube 230Da in the x direction, and then is folded back by the pipe 230Db and flows in the water passage tube 230Da in the −x direction.

  In such a configuration, the tank for supplying the cooling water to the water flow tube 230D does not exist on the y direction side of the corrugated fin 150 at least on the tank 110 side, and therefore, the y direction of the heat exchanger 10D is aligned. The dimensions will not increase. Further, in this portion, since the tank does not hinder the flow of air passing through the corrugated fins 150, heat exchange with air can be performed more efficiently.

  Subsequently, a heat exchanger 10E according to a sixth embodiment of the present invention will be described with reference to FIGS. The heat exchanger 10E is different from the heat exchanger 10 with respect to the shape of the second tube 140E, but the other configurations are generally the same as the heat exchanger 10.

  In the present embodiment, a portion of the second end 142E of the second tube 140E that faces the tank 210 along the y direction has a shape that locally hangs downward. In such a configuration, since the tank 210 can be brought closer to the second tube 140E side (−y direction side), the dimension along the y direction of the heat exchanger 10E can be reduced.

  Subsequently, a heat exchanger 10F according to a seventh embodiment of the present invention will be described with reference to FIG. The heat exchanger 10F is different from the heat exchanger 10 in terms of the shape and arrangement of the second tube 140F, but is otherwise substantially the same as the heat exchanger 10 in other configurations.

  In the present embodiment, the cross-sectional shape when the second tube 140F is cut along a plane perpendicular to the longitudinal direction is the cross-sectional shape when the first tube 130 is cut along a plane perpendicular to the longitudinal direction. It is the same. However, the position of each second tube 140F is on the y-direction side with respect to the position of the first tube 130. For this reason, the second end portion 142F of the second tube 140F is disposed at a position on the y direction side with respect to the first end portion 132 of the first tube 130, and inside the concave portion 241 formed in the plate fin 240. The second end 142F is accommodated. In such a configuration, since it is not necessary to use two types of tubes (the first tube 130 and the second tube 140) having different shapes, it is possible to suppress the cost of parts for manufacturing the heat exchanger 10F. .

  Subsequently, a heat exchanger 10G according to an eighth embodiment of the present invention will be described with reference to FIG. The heat exchanger 10G is different from the heat exchanger 10 in that it does not have the first tube 130 and in the number of water flow tubes 230, but the other configurations are generally the same as the heat exchanger 10.

  In the present embodiment, the first tube 130 in the heat exchanger 10 is not provided, and all the tubes through which the refrigerant flows are the second tubes 140. That is, each of the tubes (second tubes 140) has the same cross-sectional shape when cut along a plane perpendicular to the longitudinal direction. Further, the second end portions 142 of all the tubes (second tubes 140) are accommodated in the concave portions 241 of the plate fins 240. Since the second tube 140 is added as an alternative to the first tube 130, the number of the second tubes 140 is larger than that of the heat exchanger 10, and the number of the recesses 241 is also increased accordingly. .

  In addition, one water passage tube 230 penetrating the plate fin 240 is always arranged at a position between two adjacent recesses 241. As a result, the number of water flow tubes 230 in the present embodiment is greater than the number of water flow tubes 230 in the heat exchanger 10. As described above, in implementing the present invention, it is also desirable to appropriately change the number of the water passage tubes 230 in consideration of the size of the plate fins 240 and the number of the second tubes 140 to obtain appropriate heat dissipation performance.

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. In other words, those specific examples that have been appropriately modified by those skilled in the art are also included in the scope of the present invention as long as they have the characteristics of the present invention. For example, the elements included in each of the specific examples described above and their arrangement, materials, conditions, shapes, sizes, and the like are not limited to those illustrated, but can be changed as appropriate. Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

20: Heat pump system 30: Air conditioning unit 10, 10A, 10B, 10C, 10D, 10E, 10F, 10G: Heat exchanger 110, 110A, 120, 210, 210B, 220: Tank 130: First tube 132: First end Portions 140, 140E, 140F: second tubes 142, 142E, 142F: second end portions 230, 230C, 230D: water flow tubes 240: plate fins 241: recesses

Claims (13)

A heat exchanger that functions as an evaporator through which a refrigerant having a temperature lower than the outside temperature passes,
The first fluid, which is the refrigerant, flows through the inside and is arranged in the air flow to constitute a heat exchanging portion, and end portions (132, 142, 142E, 142F) and tubes (130, 140, 140E, 140F),
A receiving portion (241) that is disposed close to the tube in the upstream in the first direction, has a higher temperature than the tube, and into which at least a part (140, 142E, 142F) of the end portion enters. And a blockage suppression unit (230, 230C, 230D, 240) provided with a heat exchanger. The tube has a first tube (13 0 ) and a second tube (14 0 , 14 0 E, 14 0 F),
The first tube has a first end (132) that is an upstream end in the first direction;
The second tube has a second end portion (142, 142E, 142F) that is an upstream end portion in the first direction, and the second end portion is more in the first direction than the first end portion. The heat exchanger according to claim 1, wherein the heat exchanger is arranged on the upstream side.   Each of the plurality of first tubes and the second tubes are arranged side by side along a second direction intersecting with the first direction, and at least in a part of the arrangement order, the first tube is next to the first tube. The heat exchanger according to claim 2, wherein the second tube is disposed.   The occlusion suppression part (240) is provided with a longitudinal portion so as to be close to both the first tube and the second tube, and is arranged so that the extending direction of the longitudinal portion is directed downward from above. The heat exchanger according to claim 3.   The clogging suppression part (230, 230C, 230D) is at a temperature higher than that of the first tube and the second tube by flowing a second fluid having a temperature higher than that of the first fluid. Item 5. The heat exchanger according to Item 4.   The heat exchanger according to any one of claims 1 to 5, wherein the temperature of the first fluid and the temperature of the blockage suppression unit are set higher than the temperature of air in the heat exchange unit. A first tank (110A) for supplying the first fluid to the tube;
7. The recess portion (111 </ b> A) in which a part of the blockage suppressing portion (230 </ b> A) is accommodated is formed on the upstream surface of the first tank in the first direction. The heat exchanger according to item. A second tank (210B) for supplying the second fluid to the blockage suppressing portion;
The heat exchanger according to claim 5, wherein a concave portion (211B) in which a part of the end portion is accommodated is formed on a downstream surface of the second tank in the first direction. A first tank (110) for supplying the first fluid to the tube;
The blockage suppressing portion is a pipe having a flat cross section, and further includes a horizontal pipe (230C) penetrating the longitudinal portion in the horizontal direction,
6. The heat exchanger according to claim 5, wherein at least a portion of the horizontal pipe facing the first tank has a longitudinal direction of the flat shape extending in a vertical direction. The blockage suppressing portion further includes a plurality of horizontal pipes (230 Da) penetrating the longitudinal portion in the horizontal direction,
The heat exchanger according to claim 5, wherein ends of the horizontal pipes adjacent to each other are connected by a U-shaped pipe (230Db). A second tank (210) for supplying the second fluid to the blockage suppressing portion;
The heat exchanger according to claim 5, wherein a portion of the second end portion (142E) facing the second tank is locally hanging downward.   A cross-sectional shape when the first tube is cut along a plane perpendicular to the longitudinal direction, and a cross-sectional shape when the second tube (142F) is cut along a plane perpendicular to the longitudinal direction. The heat exchanger according to claim 2 which is mutually the same.   The heat exchanger according to claim 1, wherein a cross-sectional shape of the tube cut along a plane perpendicular to the longitudinal direction thereof is the same for all the tubes.

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