JP2013071617A - Heat medium heating device and vehicle air conditioner equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat medium heating device which secures heat radiating performance and electrical insulating performance of a control board having a thermogenic electric component mounted thereon, which has stabilized quality, which is reduced in thickness, and which has a reduced size and improved performance, and a vehicle air conditioner equipped with the same.SOLUTION: The heat medium heating device includes: a PTC heater laminated between a plurality of flat heat exchange tubes; a heat exchange pressing member 15 for pressing and fixing the flat heat exchange tubes and the PTC heater to the inner face of a casing; and the control board 17 disposed on the heat exchange pressing member 15 via an insulating sheet 16 and having a control circuit 21 including the thermogenic electric component 20 for controlling the PTC heater mounted on the surface thereof. A heat conductive liquid gap filling material and a heat conductive insulator such as a low hardness insulating heat conductive sheet are interposed between the insulating sheet 16 and/or the heat exchange pressing member 15 and a heat penetration part of the heat medium heating device capable of transmitting generated heat of the thermogenic electric component 20 to the heat exchange pressing member 15 via the heat penetration part and cooling the thermogenic electric component 20.

Description

  The present invention relates to a heat medium heating device that heats a heat medium using a PTC heater, and a vehicle air conditioner including the heat medium heating device.

  In a vehicle air conditioner applied to an electric vehicle, a hybrid vehicle, or the like, a positive temperature coefficient thermistor element (hereinafter referred to as “Positive Temperature Coefficient”) is used as one of heat medium heating devices that heat a medium to be heated as a heat source for heating. A device using a PTC heater having a heat generating element as a PTC element) is known. In such a heat medium heating device, Patent Document 1 provides a plurality of partition walls that divide the inside of the housing having the heat medium inlet and outlet into a heating chamber and a heat medium circulation chamber, and is partitioned by the partition walls. In addition, a PTC element is inserted and installed on the heating chamber side so as to be in contact with the partition wall, and the PTC element sandwiches the partition wall and heats the heat medium flowing through the circulation chamber side.

  In Patent Document 2, a PTC heater is configured by providing an electrode plate, an insulating layer, and a heat transfer layer on both sides of a PTC element, and an inlet and an outlet for a heat medium are provided on both sides of the PTC heater. A heat medium heating device having a laminated structure in which a pair of heat medium flow boxes communicated with each other and a substrate housing box for housing a control board and a lid are provided on the outer surface side of the heat medium circulation box is disclosed. .

  However, in the thing of patent document 1, it is difficult to insert and install a PTC element in close contact between the partition walls serving as a heat transfer surface, and the contact thermal resistance between the partition walls and the PTC element increases, resulting in a decrease in heat transfer efficiency. was there. Moreover, in the thing of patent document 2, although the adhesiveness of a PTC heater and a heat carrier distribution box can be improved and contact thermal resistance can be reduced, since it is difficult to arrange | position a multilayer PTC heater, a plane area becomes large. At the same time, a heat medium distribution box and a dedicated substrate storage box are required, and there are limits to the reduction in size and weight and cost.

  Therefore, a heat medium heating device has been developed that uses a heat exchanger tube with a flat structure and forms a heat exchange element by alternately laminating flat heat exchanger tubes and PTC heaters in multiple layers and incorporating them into the casing. Has been. In the thing using the heat exchange element of such a laminated structure, in patent document 3, by applying a compressive load from the thickness direction with respect to the laminated flat heat exchanger tube, between flat heat exchanger tubes There is disclosed a structure in which a component to be cooled and a flat heat exchanger tube that are stacked on each other are brought into close contact with each other.

JP 2008-7106 A JP 2008-56044 A Japanese Patent No. 4100368

  As described above, in the heat medium heating device having a configuration in which PTC heaters are alternately stacked between a plurality of flat heat exchanger tubes, power is supplied to the electrode plate of the PTC heater via the control board. The control board is disposed on a heat exchange pressing member for pressing and incorporating the heat exchange element on the inner surface of the casing. However, since a control circuit including a power transistor (heat generating electrical component) such as an FET or IGBT for performing energization control on the PTC heater is surface-mounted on the control board, the control board and the heat exchange pressing member The problem is how to ensure the cooling performance for the heat-generating electrical components such as the power transistor while ensuring the insulation between the two.

  The present invention has been made in view of such circumstances, and ensures heat dissipation and electrical insulation of a control board on which a heat-generating electrical component such as a power transistor is mounted, and stabilizes quality. , Heat medium heating device with small size and high performance, improved heat transfer efficiency by reducing contact thermal resistance between flat heat exchanger tube and PTC heater, and vehicle equipped with the same The purpose is to provide an air conditioner for a vehicle.

In order to solve the above-described problems, the heat medium heating device of the present invention and the vehicle air conditioner including the same employ the following means.
That is, the heat medium heating device according to the present invention includes a plurality of flat heat exchange tubes that are flown out of the outlet header portion after the heat medium flowing in from the inlet header portion flows through the flat tube portion, and a plurality of the heat exchanger tubes stacked on each other. The PTC heater incorporated between the flat tube portions of the flat heat exchanger tubes, and the alternately stacked flat heat exchanger tubes and the PTC heater are pressed against the inner surface of the casing from one surface side of the flat heat exchanger tubes. And a control board on which a control circuit including an exothermic electrical component that controls the PTC heater is mounted on the top surface of the heat exchanger pressing member via an insulating sheet. And the heat-generating electrical component includes a heat-penetrating member provided in correspondence with a mounting position on the control board, and the heat-intersecting member as a heat sink. A heat medium heating device capable of being cooled via a sheet, wherein a thermally conductive liquid gap is filled between the heat penetration portion on the control board side and the insulating sheet and / or the heat exchanger pressing member. A heat conductive insulator such as a material and a low hardness insulating heat conductive sheet is interposed.

  A plurality of flat heat exchanger tubes and PTC heaters are alternately stacked on the inner surface of the casing by being pressed by a heat exchanger pressing member, and a control board for controlling the PTC heater is provided on the heat exchanger pressing member with an insulating sheet. The heat-generating electric component disposed on the control board and mounted on the surface of the control board can be cooled by the heat exchanger pressing member as a heat sink, and can be cooled via the heat penetration part of the control board and the insulating sheet. In that case, variations in heat dissipation and electrical insulation due to variations in the amount of retraction and pop-out of the heat penetration part from the back side of the control board may cause quality deterioration, but the control board side heat penetration part and insulation sheet In addition, a heat conductive insulator such as a heat conductive liquid gap filler, a low hardness insulating heat conductive sheet or the like is interposed between the heat exchanger pressing member and The product is surface-mounted on the control board, and the control board is directly placed on the top surface of the heat exchanger pressing member via an insulating sheet, so that the heat generation of the heat-generating electrical components is reduced even when the dimension in the thickness direction is reduced. Regardless of manufacturing variations in the heat penetration part, the heat penetration part, the heat conductive liquid gap filler, and the heat conduction insulator such as a low hardness insulating heat conduction sheet can be securely attached to the back side of the control board. The heat exchanger pressing member can be cooled as a heat sink. Therefore, the heat dissipation and electrical insulation of the control board on which the heat-generating electrical components are surface-mounted can be ensured, and the quality of the heat medium heating device can be stabilized and improved. In addition, the flat heat exchange tubes and the PTC heaters are alternately laminated and pressed by the heat exchange pressing member so as to be in close contact with each other. The medium heating device can be reduced in size and performance, and the control board on which heat-generating electrical components are surface-mounted is placed directly on the heat exchanger pressing member via an insulating sheet. (Direction), the size can be reduced, and the heating medium heating device can be made compact.

  Furthermore, the heat medium heating device of the present invention is characterized in that, in the heat medium heating device, the insulating sheet is a sheet having high hardness and heat conductivity.

  According to the present invention, since the insulating sheet is a sheet having high hardness thermal conductivity, it is possible to sufficiently ensure electrical insulation between the control board and the heat exchanger pressing member, Heat generated by heat-generating electrical components transmitted through a heat-conductive insulator such as a heat-conductive liquid gap filler and a low-hardness insulating heat-conductive sheet is radiated to the heat-holding member, and the heat-holding member is used as a heat sink. Can cool steadily. Therefore, it is possible to ensure heat dissipation and electrical insulation of the control board on which the heat generating electrical components are surface-mounted. For example, a high hardness silicone sheet can be used as the insulating sheet having high thermal conductivity.

  Furthermore, in the heat medium heating device according to the present invention, in the heat medium heating device, the insulating sheet is provided with an opening corresponding to a portion where the heat conductive liquid gap filler is interposed. It is characterized by that.

  According to the present invention, since the opening is provided corresponding to the portion where the heat conductive liquid gap filler is interposed in the insulating sheet, the heat conductive liquid gap filler is filled or arranged in the opening. By assembling the control board, the heat penetration part on the control board side and the thermally conductive liquid gap filling material are made to correspond to each other, and heat is generated from the heat-generating electrical parts regardless of the amount of retraction or protrusion of the heat penetration part. It is possible to radiate heat directly to the heat exchanger pressing member through the penetrating portion and the heat conductive liquid gap filler. Moreover, even if it uses what is hardened | cured from a liquid instead of a solid thing as a heat conductive liquid gap filler, it can be filled and hold | maintained in an opening part. Therefore, it is possible to reliably form a heat dissipation path from the heat-generating electrical component and ensure its cooling performance. In this case, the insulating sheet can be used as a sheet of high-hardness dedicated for insulation, for example, a sheet of polyimide film or the like. Well, cost can be reduced.

  Furthermore, the heat medium heating device of the present invention is characterized in that, in the heat medium heating device, an area of the opening is larger than an area of the heat penetration portion.

  According to the present invention, since the area of the opening is larger than the area of the heat penetration part, even if the heat exchanger pressing member, the insulating sheet, the control board, etc. are misaligned with each other due to accumulation of dimensional tolerances, A penetration part and a heat conductive liquid gap filler can be made to correspond reliably. Therefore, it is possible to reliably form a heat radiation path from the heat-generating electrical component and to ensure its cooling performance.

  Furthermore, in the heat medium heating device of the present invention, in any one of the above-described heat medium heating devices, the insulating sheet is divided into at least two parts and is installed corresponding to a portion where the heat penetration portion is provided. The sheet is an insulating sheet having high thermal conductivity, and the insulating sheet installed corresponding to other portions is a sheet dedicated to high-hardness insulation.

  According to the present invention, the insulating sheet is divided into at least two parts, and the insulating sheet installed corresponding to the portion provided with the heat penetration part is an insulating sheet having high hardness thermal conductivity. Since the insulation sheet installed corresponding to the part is a sheet dedicated to high-hardness insulation, the insulation sheet installed in the part where it is necessary to ensure both electrical insulation and thermal conductivity functions. Uses a high-hardness silicone sheet or the like having both functions, while a sheet such as an inexpensive polyimide film can be used as a sheet to be installed in a portion that only needs to ensure electrical insulation. . Therefore, it is possible to reduce the cost while sufficiently securing both functions of electrical insulation and heat dissipation required for the insulating sheet.

  Furthermore, in the heat medium heating device of the present invention, in any one of the heat medium heating devices described above, a plurality of protrusions are provided on the surface of the heat exchanger pressing member, and the insulating sheet and / or the control board are provided. The insulating sheet and / or the control board can be positioned by fitting a hole provided in the protrusion.

  According to the present invention, a plurality of protrusions are provided on the surface of the heat exchanger pressing member, and a hole provided in the insulating sheet and / or the control board is fitted into the protrusion, whereby the insulating sheet and / or control is performed. Since the substrate can be positioned, when the insulating sheet and / or the control board is disposed on the heat exchanger pressing member, the hole on the insulating sheet and / or control board side is formed with respect to the protrusion on the heat exchanger pressing member side. By fitting, each can be reliably positioned and assembled. Therefore, the position of the heat penetration part on the control board side and the heat conductive insulator such as the heat dissipation gap filler and the low-hardness heat conductive sheet can be reliably matched, and the assembling accuracy and assembling workability can be improved. Can do.

  Furthermore, the heat medium heating device of the present invention is characterized in that, in any one of the heat medium heating devices described above, the heat exchanger pressing member is a plate made of an aluminum alloy.

  According to the present invention, since the heat exchanger pressing member is a plate made of aluminum alloy, heat generated from the heat-generating electrical component mounted on the control board is transferred to the heat penetration portion, the insulating sheet, and / or the heat conduction. Heat is transferred to the heat exchanger presser member, which is made of a lightweight aluminum alloy plate with good thermal conductivity, through a heat conductive insulator such as a conductive liquid gap filler and a low hardness insulating heat conductive sheet. The heat-generating electrical component can be cooled by radiating heat to the heat exchanger pressing member that uses the exchange tube as a cooling source. Therefore, it is possible to improve the cooling performance of the heat-generating electrical components that are surface-mounted on the control board by using the heat exchanger pressing member as a heat sink, improve heat reliability, and maintain weight reduction. it can.

  Furthermore, the vehicle air conditioner according to the present invention is configured such that the heat medium heated by the heat medium heating device can be circulated with respect to the radiator disposed in the air flow path. The heat medium heating device is any one of the above-described heat medium heating devices.

  According to the present invention, since the heat medium heated by any one of the above-described heat medium heating devices can be circulated with respect to the radiator disposed in the air flow path, The heating medium supplied to the radiator disposed in the road can be heated and supplied by the above-described heating medium heating device that is high quality, high reliability, small size, and high performance. it can. Therefore, the reliability of the vehicle air conditioner and the air conditioning performance thereof, particularly the heating performance can be improved, and the mountability of the air conditioner on the vehicle can be improved.

  According to the heating medium heating apparatus of the present invention, the heat generating electrical component is surface-mounted on the control board, and the control board is directly disposed on the upper surface of the heat exchanger pressing member via the insulating sheet, thereby reducing the thickness direction dimension. Even when it is reduced, the heat conduction of the heat-generating electrical component is not limited by the manufacturing variation of the heat-penetrating part, and the heat conduction of the heat-penetrating part, the heat-conductive liquid gap filler, the low-hardness insulating heat-conducting sheet, etc. Heat can be reliably transferred to the back side of the control board via an insulator, and the heat exchanger foot can be cooled as a heat sink, ensuring heat dissipation and electrical insulation of the control board with heat-generating electrical components mounted on the surface. In addition, the quality of the heat medium heating device can be stabilized and improved. In addition, the flat heat exchange tubes and the PTC heaters are alternately laminated and pressed by the heat exchange pressing member so as to be in close contact with each other. The medium heating device can be reduced in size and performance, and the control board on which the heat-generating electrical parts are surface-mounted is placed directly on the heat exchanger pressing member via an insulating sheet. The thickness direction) can be reduced, and the heat medium heating device can be made compact.

  Further, according to the vehicle air conditioner of the present invention, the heat medium supplied to the radiator disposed in the air flow path is high quality, high reliability, small size and high performance. Since it can be heated and supplied by the above-described heat medium heating device, the reliability of the vehicle air conditioner and its air conditioning performance, particularly the heating performance can be improved, and the mountability of the air conditioner to the vehicle can be improved. Can be improved.

It is a schematic block diagram of the vehicle air conditioner provided with the heat-medium heating device which concerns on 1st Embodiment of this invention. It is a disassembled perspective view of the heat carrier heating apparatus shown in FIG. It is a top view of the state which removed the upper case of the heat carrier heating apparatus shown in FIG. It is an AA cross-section equivalent figure in FIG. It is a disassembled perspective view of the heat exchanger pressing member and control board of the heat carrier heating apparatus shown in FIG. It is a top view of the heat exchanger pressing member and control board shown in FIG. It is a BB cross-section equivalent figure in FIG. It is CC sectional equivalent drawing in FIG. It is a disassembled perspective view of the heat exchanger pressing member and control board of the heat carrier heating apparatus which concerns on 2nd Embodiment of this invention. It is a top view of the heat exchanger pressing member and control board shown in FIG. It is the DD sectional view equivalent figure in FIG.

Embodiments according to the present invention will be described below with reference to the drawings.
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic configuration diagram of a vehicle air conditioner including a heat medium heating device according to the first embodiment of the present invention. The vehicle air conditioner 1 is provided with a casing 3 that forms an air flow passage 2 for taking outside air or vehicle interior air and adjusting the temperature thereof, and then guiding it to the vehicle interior.

  Inside the casing 3, the air or the passenger compartment air is sequentially sucked from the upstream side to the downstream side of the air flow passage 2 to increase the pressure, and the blower 4 pumps it to the downstream side. The flow rate ratio of the cooler 5 that cools the air, the radiator 6 that heats the air that has passed through the cooler 5, and the amount of air that passes through the radiator 6 and the amount of air that bypasses the radiator 6 An air mix damper 7 that adjusts the temperature of the temperature-controlled air by adjusting and air-mixing on the downstream side thereof is installed.

The downstream side of the casing 3 is connected to a plurality of outlets that blow out the temperature-controlled air into the vehicle compartment via an outlet mode switching damper and a duct (not shown).
The cooler 5 constitutes a refrigerant circuit together with a compressor, a condenser, an expansion valve, etc., not shown, and cools the air passing therethrough by evaporating the refrigerant adiabatically expanded by the expansion valve. . The radiator 6 constitutes a heat medium circulation circuit 10 </ b> A together with the tank 8, the pump 9, and the heat medium heating device 10, and a high-temperature heat medium (for example, antifreeze liquid) heated by the heat medium heating device 10 is pump 9. The air passing therethrough is heated by being circulated through the.

2 is an exploded perspective view of the heat medium heating device 10 shown in FIG. 1, FIG. 3 is a plan view of the heat medium heating device 10 with the upper case removed, and FIG. FIG. 3 is a cross-sectional view corresponding to AA in FIG.
As shown in FIG. 2, the heat medium heating device 10 is a box-shaped casing 11 (however, only the lower case 11A constituting the casing 11 is shown, and the upper case constituting the upper half thereof is not shown. A heat exchange module 14 in which a plurality of (for example, three) flat heat exchange tubes 12 and a plurality of sets of PTC heaters 13 are alternately stacked, and the heat exchange module 14 is a lower case of the casing 11. A heat exchanger pressing member 15 for pressing and fixing to the inner bottom surface of 11A, and a PTC heater 13 disposed on the upper surface of the heat exchanger pressing member 15 via an insulating sheet 16 (see FIG. 5) to be described later are controlled. And the control board 17 to be configured.

  The casing 11 has a box-shaped configuration that is divided into an upper half and a lower half, and an upper case (not shown) located in the upper half with respect to the lower case 11A located in the lower half. ) Are screwed and fixed to be integrated. The heat exchange module 14 including the flat heat exchange tube 12 and the PTC heater 13, the heat exchange pressing member 15, the insulating sheet 16, the control board 17, and the like are accommodated and installed in the internal space of the casing 11. ing.

  On the lower surface of the lower case 11A, a heat medium inlet channel 11B for guiding the heat medium introduced into the three laminated flat heat exchanger tubes 12 and a heat medium flowing through the flat heat exchanger tubes 12 are derived. The heat medium outlet passage 11C is integrally formed so as to protrude downward, and the boss portions 11D (four locations) for fastening and fixing the heat exchanger pressing member 15 are integrally formed so as to protrude upward. Has been. The lower case 11A is formed of a resin material, such as PPS (polyphenylene sulfide), whose linear expansion coefficient is close to that of the aluminum alloy material forming the flat heat exchanger tube 12 accommodated and installed in the inner space. Note that the upper case is also preferably formed of the same resin material as the lower case 11A.

  Further, a power harness hole and an LV harness hole (both not shown) are formed in the lower surface of the lower case 11A so as to penetrate through the distal end portions of the power harness 18 and the LV harness 19. The power harness 18 is for supplying power to the PTC heater 13 via the control board 17, and has two power harness terminal blocks provided on the control board 17 with the tip portion branched in a bifurcated shape. It can be screwed to 17A via a screw or the like. Further, the LV harness 19 is for transmitting a control signal to the control board 17, and a tip end portion thereof is connectable to the control board 17.

  The control board 17 performs energization control for a plurality of sets of PTC heaters 13 based on a command from the host control unit (ECU), and includes a plurality of power transistors (heat-generating electrical components) 20 made of FETs, IGBTs, or the like. The control circuit 21 including the surface is mounted on the surface, and the energization state of the plurality of sets of PTC heaters 13 can be switched via the control circuit 21. The control board 17 shown in FIGS. 2 and 3 and the control board 17 shown in FIGS. 5 and 6 are illustrated with different arrangements of the heat-generating electrical component 20 and the control circuit 21, but are functionally the same. It is. The control board 17 has a heat penetration made of a highly thermally conductive material such as copper or aluminum so as to penetrate through both sides of the board corresponding to a portion where a plurality of power transistors 20 which are heat-generating electrical components are mounted. The portion 22 (see FIG. 7) is provided.

  Then, a plurality of flat heat exchanger tubes 12 are laminated so as to sandwich the plurality of sets of PTC heaters 13 from both sides thereof, and a heat exchange module 14 is configured. The flat heat exchanger tube 12 is configured by superposing tube materials obtained by press-molding aluminum alloy thin plates. As shown in FIGS. 2 and 4, for example, three flat heat exchanger tubes 12 are stacked in parallel to each other, and PTC heaters 13 are stacked between the flat heat exchanger tubes 12 to constitute a heat exchange module 14.

  Each flat heat exchanger tube 12 includes a flat tube portion 12A having a flat cross-sectional shape with a thickness of about several millimeters, an inlet header portion 12B into which a heat medium is formed at both ends thereof, and an outlet through which the heat medium flows out. It is configured to include a header portion 12C, and corrugated inner fins (not shown) are inserted into the flat tube portion 12A so that a plurality of heat medium flow passages are formed in the tube. It has become. Such a flat heat exchanger tube 12 is not a special thing but is a well-known thing.

  The three flat heat exchanger tubes 12 are sequentially laminated in the order of the lower, middle, and upper stages, and the inlet header portion 12B and the outlet header portion 12C at both ends thereof are in close contact with each other via a sealing material such as an O-ring. Communication holes (not shown) provided in the portion 12B and the outlet header portion 12C are communicated with each other. The three flat heat exchanger tubes 12 are assembled in a laminated state or sequentially laminated into the inner bottom surface of the lower case 11A and, as will be described later, heat exchange that is fastened and fixed to the boss portions 11D (four locations) of the lower case 11A. It is configured to be pressed and fixed toward the inner bottom surface of the lower case 11 </ b> A via the pressing member 15.

  Also, a plurality of sets (for example, two sets) of PTC heaters 13 constituting the heat exchange module 14 by being sandwiched between the three flat heat exchanger tubes 12, as is well known, are PTC elements (Positive Temperature). The electrode plates 24 are disposed in contact with the upper and lower surfaces of the (Coefficient) 23, and are laminated between the three flat heat exchanger tubes 12 with an insulating sheet or the like interposed therebetween. The PTC heater 13 is incorporated into the inner bottom surface of the lower case 11A while being laminated together with the three flat heat exchanger tubes 12 or sequentially laminated, and the inner bottom surface of the lower case 11A via the heat exchanger pressing member 15 as described above. It is designed to be pressed and fixed.

  The electrode plate 24 is for supplying electric power to the PTC element 23, and is made of an aluminum alloy plate material having a rectangular shape in plan view. This electrode plate 24 is disposed on both sides of the PTC element 23 so as to be in contact with the upper surface of the PTC element 23 and one sheet so as to be in contact with the lower surface of the PTC element 23. The PTC element 23 is sandwiched between the upper and lower surfaces by the electrode plate 24.

  Furthermore, the electrode plate 24 disposed on the upper surface side of the PTC element 23 is disposed such that the upper surface thereof is in contact with the lower surface of the flat heat exchanger tube 12, and the electrode plate 24 disposed on the lower surface side of the PTC element 23 is The lower surface is arranged so as to be in contact with the upper surface of the flat heat exchanger tube 12. In the present embodiment, the electrode plate 24 is provided between the lower flat heat exchanger tube 12 and the middle flat heat exchanger tube 12, and between the middle flat heat exchanger tube 12 and the upper flat heat exchanger tube 12. Two sheets, a total of four sheets, are arranged.

  These four electrode plates 24 have substantially the same shape as the flat tube portion 12A of each flat heat exchanger tube 12, and one terminal 24A is integrally provided on each long side. The terminals 24A are arranged along the long side direction of the electrode plates 24 so that they do not overlap when the electrode plates 24 are stacked. That is, the terminals 24A provided on each electrode plate 24 are provided so that the positions are slightly shifted along the long side direction, and are arranged in series when the electrode plates 24 are stacked. It has been. Each terminal 24A is bent and formed in an L shape so as to protrude upward, and a plurality of sets (four sets) of terminal blocks 17B arranged in parallel on one side of the front surface of the control board 17 via screws or the like. To be connected.

  The three flat heat exchanger tubes 12 and the two sets of PTC heaters 13 are assembled on the inner bottom surface of the lower case 11A while being laminated or sequentially laminated as described above, and the upper surface of the uppermost flat heat exchanger tube 12 Are pressed in the direction of the inner bottom surface of the lower case 11A via the heat exchanger pressing members 15 that are fastened and fixed to the boss portions 11D (four locations) of the lower case 11A by four screws 25, thereby each flat heat exchanger tube. The upper and lower surfaces of the 12 inlet header portions 12B and the outlet header portion 12C and the flat tube portions 12A of the flat heat exchanger tubes 12 and the upper and lower surfaces of the PTC heater 13 are brought into close contact with each other.

  As a result, the heat exchange module 14 is incorporated into the casing 11, and the heat medium introduced from the heat medium inlet passage 11 </ b> B of the lower case 11 </ b> A flows from the inlet header portion 12 </ b> B of each flat heat exchanger tube 12 into the flat tube portion 12 </ b> A. In the process of being guided and flowing through the flat tube portion 12A, the temperature is raised by the PTC heater 13 and flows out to each outlet header portion 12C, from there through the heat medium outlet passage 11C of the lower case 11A, the heat medium heating device 10 It will be derived to the outside. The heat medium derived from the heat medium heating device 10 is supplied to the radiator 6 via the heat medium circulation circuit 10A (see FIG. 1).

  The heat exchanger pressing member 15 has a function as a heat sink for cooling a plurality of heat-generating electrical components 20 mounted on the surface of the control board 17 through a heat penetration portion 22 made of a highly heat conductive material such as copper or aluminum. It is made of an aluminum alloy plate. The heat exchanger pressing member 15 is sized to cover the upper surface of the flat heat exchanger tube 12, and presses the heat exchange module 14 including the flat heat exchanger tube 12 and the PTC heater 13 against the inner bottom surface of the lower case 11A. When fixing, in order to ensure the sealing performance around the inlet header portion 12B and the outlet header portion 12C, it is configured to be fastened and fixed to the boss portion 11D of the casing 11 by a screw 25 at a position passing through the center line. .

  A control board 17 on which a control circuit 21 including a heat-generating electrical component 20 that controls the PTC heater 13 is mounted is screwed together with a plurality of screws 26 via an insulating sheet 16 on the upper surface of the heat exchanger pressing member 15. It is supposed to be fixed. The insulating sheet 16 and the control board 17 have a plurality of holes 16A and 17C provided in the insulating sheet 16 and the control board 17 respectively with respect to the protrusions 15A provided in a plurality of positions on the upper surface of the heat exchanger pressing member 15. By fitting, it is configured to be positioned and assembled (see FIG. 8).

  The heat penetration part 22 provided corresponding to the heat-generating electrical component 20 by assembling the control board 17 is in contact with the heat exchanger pressing member 15 that penetrates the insulating sheet 16 or functions as a heat sink via the insulating sheet 16. Configured as follows. However, the amount of retraction and protrusion from the back surface of the control board 17 of the heat penetration part 22 varies due to manufacturing, so that the heat penetration part 22 is attached to the heat exchanger pressing member 15 and the insulating sheet 16 by the above assembly. There is no guarantee that the contact is normal, and heat dissipation and electrical insulation of the control board 17 are not ensured.

  Therefore, in the present embodiment, a plurality of openings 16B are provided in a portion corresponding to the heat penetration part 22 of the insulating sheet 16, and the insulating heat conduction is provided to the openings 16B as shown in FIG. By interposing a thermally conductive liquid gap filler (thermal conductive insulator) 27 made of a material, variations in manufacturing of the thermal penetration part 22 are absorbed, and the thermal penetration part 22 and the heat exchanger pressing member 15 are It is configured to be surely thermally connected while maintaining electrical insulation. In addition, as the thermally conductive liquid gap filler 27 having an insulating property, for example, a thermally conductive silicone elastomer, using silicone as a base resin, a core material, fiberglass, alumina, or the like as a filler, Solid materials, those cured from a liquid, and the like are known, and function as a shape following elastic body after being cured from a liquid or in a solid state.

  Further, in the present embodiment, on the premise that the thermally conductive liquid gap filler 27 that is cured from a liquid is used, the insulating sheet 16 is provided with an opening 16B, and the area of the opening 16B is set to the area of the thermal through-hole 22. Even if the heat exchanger pressing member 15, the insulating sheet 16, the control board 17, etc. are relatively displaced due to the accumulation of dimensional tolerances, the heat conductive liquid gap interposed in the opening 16B is filled. The material 27 and the heat penetration part 22 are made to correspond reliably. In the case of this embodiment, the insulating sheet 16 does not need to have thermal conductivity, and a sheet of high hardness dedicated to insulation having electrical insulation, for example, a sheet such as a polyimide film can be used.

  The control board 17 assembled on the heat exchanger pressing member 15 as described above is connected to the power harness 18 branched in a bifurcated manner with respect to the terminal block 17A, and the LV harness 19 is connected to the connector. Further, a terminal 24A extended from the electrode plate 24 of the PTC heater 13 is directly connected to the terminal block 17B via a screw or the like, whereby the electrical system is connected, thereby the control board. 17 is incorporated on the heat exchanger pressing member 15 and is configured to be housed and installed in the casing 11.

  The heat medium heating device 10 described above includes three flat heat exchanger tubes 12 and two sets of PTC heaters 13 on the inner bottom surface of the lower case 11A of the casing 11, and both sides of the PTC heaters 13 with insulating sheets (not shown). ), And stacking them one by one in order, and when the heat exchange module 14 is installed, press the upper surface with the heat exchanger pressing member 15 and fasten it to the lower case 11A. After the heat exchange module 14 is sub-assembled, it is assembled in the lower case 11A, and its upper surface is pressed and fixed by the heat exchanger pressing member 15, thereby bringing the flat heat exchanger tubes 12 and the PTC heaters 13 into close contact with each other. It can be assembled in the state.

  Subsequently, the insulating sheet 16 is positioned and stacked on the upper surface of the heat exchanger pressing member 15 by fitting the holes 16A into the protrusions 15A, and the thermally conductive liquid gap filler is further formed in the opening 16B of the insulating sheet 16. 27 is filled. On the insulating sheet 16, the control board 17 is positioned and laminated by fitting the holes 17 </ b> C into the protrusions 15 </ b> A, and the control board 17 is fixed to the heat exchanger pressing member 15 with screws 26. Thereafter, the heating medium heating device 10 can be assembled by connecting the electrical system and screwing and fixing the upper case (not shown) to the lower case 11A so as to cover the upper part.

  The heat medium heating device 10 manufactured in this way is incorporated in the heat medium circulation circuit 10A of the vehicle air conditioner 1, and a plurality of flat heat exchangers convert the heat medium flowing into the inlet header portion 12B through the heat medium inlet passage 11B. After being circulated through the tube 12 and heated by the PTC heater 13, it is supplied from the outlet header portion 12C through the heat medium outlet passage 11C to heat the heat medium circulated in the heat medium circulation circuit 10A. It has become so.

Thus, according to the heat medium heating device 10 and the vehicle air conditioner 1 of the present embodiment, the following operational effects can be obtained.
A plurality of flat heat exchanger tubes 12 are laminated, and each flat heat exchanger tube 12 and the PTC heater 13 are attached to the lower case 11A by the heat exchanger pressing member 15 in a state where the PTC heater 13 is sandwiched between the flat tube portions 12A. On the other hand, it is configured to be pressed and fixed. Thereby, a plurality of flat heat exchanger tubes 12 and a plurality of sets of PTC heaters 13 can be assembled in close contact with each other.

  For this reason, the contact heat resistance between the flat heat exchanger tube 12 and the PTC heater 13 can be reduced to improve the heat transfer efficiency, and the heat medium heating device 10 can be improved in performance. By adopting a configuration in which the PTC heaters 13 are alternately laminated in multiple layers, the plane area can be reduced, and the heat exchange module 14 and, consequently, the heat medium heating device 10 can be made compact.

  In addition, a control board 17 on which a control circuit 21 including a heat-generating electrical component 20 such as a power transistor that controls the PTC heater 13 with an insulating sheet 16 interposed therebetween is mounted on the upper surface of the heat exchanger pressing member 15. At the same time, the control board 17 is provided with heat penetration portions 22 that are penetrated on both sides corresponding to the mounting position of the exothermic electrical component 20, and the exothermic electrical component 20 is used as a heat sink with the heat exchanger pressing member 15 as a heat sink. Cooling is possible via the part 22. For this reason, the heat-generating electrical component 20 that is surface-mounted on the control board 17 can be efficiently cooled by using the heat exchanger pressing member 15 as a heat sink through the heat penetration part 22. The heat medium heating device 10 can be ensured and the reliability to heat can be ensured, the dedicated board storage box and the like can be omitted, and the heat transfer pressing member 15 and the control board 17 can be reduced in the stacking direction dimension (thickness direction dimension). Can be reduced in size, weight and cost.

  Further, when the heat-generating electrical component 20 that is surface-mounted on the control board 17 is cooled via the heat penetration part 22, there is a manufacturing variation in the amount of retraction or protrusion from the back surface of the control board 17 of the heat penetration part 22. Even so, the insulating sheet 16 is provided with an opening 16B between the heat penetrating portion 22 and the heat exchanger pressing member 15, and a thermally conductive liquid gap filler (thermal conductive insulator) 27 having insulation is interposed. Therefore, the heat conductive liquid gap filling material 27 absorbs the manufacturing variation of the heat penetration portion 22, and the heat penetration portion 22 and the heat conductivity of the heat generating electrical component can be generated regardless of the variation. Heat can be reliably transferred to the back surface side of the control substrate 17 via the liquid gap filler 27, and the heat exchanger pressing member 15 can be cooled as a heat sink. Therefore, heat dissipation and electrical insulation of the control board 17 on which the heat generating electrical component 20 is surface-mounted can be secured, and the quality of the heat medium heating device 10 can be stabilized and improved.

  In particular, since the area of the opening 16B opened in the insulating sheet 16 is larger than the area of the heat penetration part 22, the heat exchanger pressing member 15, the insulating sheet 16, the control board 17 and the like are accumulated due to accumulation of dimensional tolerances. Even if they are misaligned with each other, the heat penetration portion 22 and the heat conductive liquid gap filler 27 can be reliably associated with each other. Therefore, a heat radiation path from the heat-generating electrical component 20 can be reliably formed and its cooling performance can be ensured.

  In the present embodiment, a plurality of protrusions 15A are provided on the surface of the heat exchanger pressing member 15, and holes 16A and 17C provided in the insulating sheet 16 and the control board 17 are fitted into the protrusions 15A. Since the insulating sheet 16 and the control board 17 can be positioned, when the insulating sheet 16 and the control board 17 are disposed on the heat exchanger pressing member 15, the insulating sheet 16 and the protrusion 15A on the heat exchanger pressing member 15 side are arranged. By fitting the holes 16A and 17C on the control board 17 side, each can be surely positioned and assembled. Therefore, the position of the heat penetration part 22 on the control board 17 side and the heat conductive liquid gap filling material (heat conductive insulator) 27 can be made to correspond reliably, and the assembling accuracy and assembling workability can be improved. Can do.

  Furthermore, in this embodiment, since the heat exchanger pressing member 15 is a plate made of aluminum alloy, the heat from the heat generating electrical component 20 on the control board 17 is transferred to the heat penetration portion 22 and the heat conductive liquid. Heat is transferred to the heat exchanger pressing member 15, which is made of a lightweight aluminum alloy plate having good thermal conductivity, through the gap filler (thermal conductive insulator) 27, and heat using the flat heat exchanger tube 12 as a cooling source. The heat generating electrical component 20 can be cooled by dissipating heat to the presser member 15. Therefore, it is possible to improve the cooling performance of the heat-generating electrical component 20 that is surface-mounted on the control board 17 by using the heat exchanger pressing member 15 as a heat sink, and it is possible to improve heat reliability and maintain weight reduction. can do.

  Further, as described above, the heat medium heated by the heat medium heating device 10 having high quality, high reliability, small size and high performance is supplied to the radiator 6 disposed in the air flow path 2. Since it can supply, while improving the reliability of the air conditioner 1 for vehicles and its air-conditioning performance, especially heating performance, the mounting property of the air-conditioner 1 with respect to a vehicle can be improved.

  In the above embodiment, the insulating sheet 16 is provided with the opening 16B, filled with a thermally conductive liquid gap filler 27 of a type that is hardened from a liquid state, and the heat penetrating part 22 and the heat penetration part on the control board 17 side. Although the thermally conductive liquid gap filler 27 is interposed between the member 15 and the insulating sheet 16, the opening 16 </ b> B is not provided and the upper surface of the insulating sheet 16 is solid so as to correspond to the heat penetration part 22. A heat conductive liquid gap filling material 27 of a type may be disposed, and a control substrate 17 may be laminated thereon. In this case, for example, a high-hardness silicone sheet having thermal conductivity is used as the insulating sheet 16. By using it, it is possible to obtain substantially the same effect as in the above embodiment.

  That is, in this embodiment, heat generated from the heat-generating electrical component 20 is transferred to the heat exchanger pressing member 15 through the heat penetration part 22, the heat conductive liquid gap filler 27, and the insulating sheet 16 having heat conductivity. The heat dissipation path can dissipate heat to the heat exchanger pressing member 15 that is a heat sink to ensure its cooling performance. In this case, instead of the heat conductive liquid gap filler 27, a heat conductive insulator interposed between the heat penetration portion 22 on the control board 17 side and the insulating sheet 16 having heat conductivity will be described later. A low-hardness insulating heat conductive sheet 38 (for example, a low-hardness silicone sheet) used in the second embodiment may be used. Note that the low-hardness insulating sheet 38 has low electrical insulation, and it is difficult to ensure insulation by itself, so it is necessary to use it together with the high-hardness insulating sheet 16.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS.
This embodiment is different from the first embodiment described above in that the insulating sheet is divided into two sheets. Since other points are substantially the same as those in the first embodiment, description thereof is omitted. Although the shapes of the heat exchanger pressing member 15 and the control board 17 and the arrangement configuration of the control circuit 21 are slightly different, there is no functional difference, and the same reference numerals are given and description thereof is omitted.
In the present embodiment, the electrical insulating sheet interposed between the heat exchanger pressing member 15 and the control board 17 is divided into an insulating sheet 36 and an insulating sheet 37.

  The insulating sheet 36 is an insulating material having high thermal conductivity that is disposed corresponding to a portion of the control board 17 where the heat-generating electrical component 20 is disposed, that is, a portion where the heat penetration portion 22 is disposed. For example, a high hardness silicone sheet or the like is used. On the other hand, the insulating sheet 37 is a high-hardness dedicated sheet for insulation that is disposed corresponding to a portion that only needs to ensure electrical insulation other than the portion provided with the heat penetration portion 22, for example, a polyimide film Such a sheet can be used. The insulating sheets 36 and 37 are provided with positioning holes 36A and 37A that are fitted into positioning protrusions 15A provided on the heat exchanger pressing member 15 side.

  The control board 17 is provided on the control board 17 side when the control board 17 is installed on the upper surface of the heat-holding member 15 with a heat-insulating high-hardness insulating sheet 36 and an insulating-use high-hardness insulating sheet 37 interposed therebetween. In order to ensure the thermal conductivity corresponding to the manufacturing variation of the thermal penetration part 22, the part corresponding to the thermal penetration part 22 between the insulating sheet 36 and the control board 17 as shown in FIG. In addition, an insulating heat conductive sheet (heat conductive insulator) 38 having a low hardness is interposed so as to absorb the manufacturing variation and transfer heat. As this low-hardness insulating heat conductive sheet (heat conductive insulator) 38, a soft low-hardness silicone sheet that can be deformed in accordance with the above-described variation can be used.

  As described above, the insulating sheet is divided into the insulating sheet 36 and the insulating sheet 37, and the insulating sheet 36 installed corresponding to the portion where the heat penetration portion 22 is provided is an insulating material having high hardness thermal conductivity. The insulating sheet 37, which is a sheet and is installed corresponding to the other portions, is a high-hardness insulating sheet. For this reason, for the insulating sheet 36 installed in a portion where it is necessary to ensure the functions of both electrical insulation and thermal conductivity, for example, a high hardness silicone sheet or the like having both functions is used. As the insulating sheet 37 that is installed in a portion that only needs to be secured, for example, an inexpensive sheet such as a polyimide film can be used, and thereby, electrical insulation and heat dissipation required for the insulating sheets 36 and 37 can be used. The cost can be reduced while sufficiently securing both functions.

  On the other hand, it is difficult to absorb the variation of the heat penetration part 22 by using the highly heat conductive insulating sheet 36, but the part corresponding to the heat penetration part 22 between the insulation sheet 36 and the control board 17. In addition, by interposing a low-hardness insulating heat conductive sheet (heat conductive insulator) 38 made of a low-hardness silicone sheet or the like, heat generated from the heat-generating electrical component 20 is transferred to the heat penetration portion 22 and low-hardness A heat radiation path for transferring heat to the heat exchanger pressing member 15 through the insulating heat conductive sheet (heat conductive insulator) 38 and the high hardness insulating sheet 36 having thermal conductivity is formed, and the heat exchanger pressing member 15 as a heat sink is formed. Cooling performance can be secured by dissipating heat. Therefore, according to this embodiment, the heat dissipation and electrical insulation of the control board 11 on which the heat generating electrical component 20 is surface-mounted can be secured, and the quality of the heat medium heating device 10 can be stabilized and improved.

  In addition, this invention is not limited to the invention concerning the said embodiment, In the range which does not deviate from the summary, it can change suitably. For example, in the above-described embodiment, the flat heat exchanger tubes 12 are laminated in three layers, and the PTC heater 13 is incorporated between them. However, the present invention is not limited to this, and the flat heat exchanger tubes 12 and the PTC heaters 13 Of course, the number of stacked layers may be increased or decreased. Moreover, in the said embodiment, although the casing 11 is made from resin material, it cannot be overemphasized that this invention is not limited to this.

  Further, in the above-described embodiment, an example has been described in which the flat heat exchanger tube 12 uses the flat heat exchanger tube 12 having a double-end header structure in which the inlet / outlet header portions 12B and 12C are formed at both ends of the flat tube portion 12A. Alternatively, a flat heat exchanger tube having a one-end header structure in which the inlet / outlet header portions 12B and 12C are arranged in parallel on one end side of the flat tube portion 12A and a U-turn flow path is formed in the flat tube portion 12A may be used.

DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 6 Radiator 10 Heat medium heating device 10A Heat medium circulation circuit 11 Casing 12 Flat heat exchanger tube 12A Flat tube portion 12B Inlet header portion 12C Outlet header portion 13 PTC heater 15 Heat exchanger pressing member 15A Protrusion 16 Insulating sheet 16A hole 16B opening 17 control board 17C hole 20 exothermic electrical component (power transistor)
21 Control circuit 22 Thermal penetration part 27 Thermal conductive liquid gap filler (thermal conductive insulator)
36 Insulation sheet (insulation sheet with high thermal conductivity)
36A Hole 37 Insulation sheet (High hardness insulation sheet)
37A Hole 38 Low hardness insulating heat conductive sheet (heat conductive insulator)

Claims (8)

A plurality of flat heat exchanger tubes that flow out from the outlet header part after the heat medium flowing in from the inlet header part flows through the flat tube part,
A PTC heater incorporated between the flat tube portions of the plurality of flat heat exchanger tubes stacked on each other;
A heat exchanger presser member that presses the flat heat exchanger tubes and the PTC heaters stacked alternately on one side of the flat heat exchanger tube against the inner surface of the casing;
A control board disposed on an upper surface of the heat exchanger pressing member via an insulating sheet and on which a control circuit including a heat-generating electrical component for controlling the PTC heater is mounted.
The heat-generating electric component has a heat sink as the heat exchanger pressing member, and is capable of cooling through a heat penetration portion provided corresponding to a mounting position on the control board and the insulating sheet. A device,
Between the heat penetration part on the control board side and the insulating sheet and / or the heat exchanger pressing member, a heat conductive insulator such as a heat conductive liquid gap filler or a low hardness insulating heat conductive sheet is interposed. A heating medium heating device characterized by being mounted.   The heating medium heating device according to claim 1, wherein the insulating sheet is a sheet having high hardness and thermal conductivity.   The heating medium heating device according to claim 1, wherein the insulating sheet is provided with an opening corresponding to a portion where the thermally conductive liquid gap filler is interposed.   The heat medium heating device according to claim 3, wherein an area of the opening is larger than an area of the heat penetration part.   The insulating sheet is divided into at least two parts, and the insulating sheet installed corresponding to the portion where the heat penetration portion is provided is an insulating sheet having high thermal conductivity, and corresponds to other portions. The heat-medium heating device according to claim 1, wherein the insulating sheet installed in this way is a sheet dedicated to high-hardness insulation.   A plurality of protrusions are provided on the surface of the heat exchanger pressing member, and by fitting holes provided in the insulating sheet and / or the control board into the protrusions, the insulating sheet and / or the The heat medium heating device according to claim 1, wherein the control board can be positioned.   The heat medium heating device according to claim 1, wherein the heat exchanger pressing member is a plate made of an aluminum alloy. In the vehicle air conditioner configured to circulate the heat medium heated by the heat medium heating device with respect to the radiator disposed in the air flow path,
The vehicle air conditioner, wherein the heat medium heating device is the heat medium heating device according to any one of claims 1 to 7.

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