Vibration-resistant structure for electronic component and heat medium heating device comprising same

Abstract

[Problem] To provide a vibration-resistant structure for an electronic component, said vibration-resistant structure improving the vibration resistance and productivity of the electronic component. [Solution] A vibration-resistant structure for a capacitor 26 having a lead part 26A connected to a control board 21 is characterized in that the capacitor 26 having relatively low vibration resistance and a coil 27 having relatively higher vibration resistance than the capacitor 26 are adjacently mounted on the control board 21, and a joint member 54 for joining the coil 27 and a part of the capacitor 26 on the side opposite to the control board 21.

Description

Vibration-resistant structure for electronic components and heat transfer medium heating device equipped with the same

[0001] The present invention relates to a vibration-resistant structure for an electronic component having leads connected to a substrate, and a heat medium heating device including the same.

[0002] Conventionally, a heat medium heating device used for air conditioning the interior of a vehicle has a heat medium flow path formed in a housing, and a cylindrical electric heater called a cartridge heater is arranged in this heat medium flow path to heat the heat medium flowing through the heat medium flow path. In this case, a plurality of (e.g., two) heat medium flow paths are provided in the housing, one end of which is connected to the other end of the heat medium flow path by a communication path, and an electric heater is arranged in each heat medium flow path. The heat medium flowing in from a heat medium inlet port formed at the other end of one heat medium flow path is heated by each electric heater, and then the heat medium flows out from a heat medium outlet port formed at the other end of the other heat medium flow path (see, for example, Patent Document 1).

[0003] Special Publication No. 2016-536197 Publication Patent No. 6405897 Publication Patent No. 3654448

[0004] In recent years, this type of heat transfer medium heater has been required to be compatible with high voltages (e.g., 800 V), and there is a demand for heat transfer medium heaters that are designed for use in higher voltage ranges than before. In order to support such high voltages, the current and voltage applied to electronic components such as IGBTs, capacitors (smoothing capacitors made of film capacitors), and common mode coils for controlling the electric heaters increases, which means that the compatible electronic components become larger.

[0005] On the other hand, since the heat medium heating device is expected to be mounted on a vehicle, high vibration resistance is required. However, as the electronic components become larger as described above, the height of the electronic components from the control board to which the lead portions are connected increases, and the distance from the control board to the center of gravity of the electronic components increases, making them more susceptible to vibration, which poses an issue regarding the strength of the joint between the electronic components and the control board.

[0006] The common mode coil described above has at least four leads, making it relatively stable and vibration-free. However, because a capacitor has only two leads, it is prone to vibrating perpendicular to the line connecting the leads. To suppress vibration in electronic components, the electronic components have been placed in a case and embedded in resin (see, for example, Patent Documents 2 and 3). However, because this structure becomes complicated, a resin bonding material is typically applied to the gap between the control board and the capacitor. However, it is difficult to suppress vibration in the portion of the capacitor opposite the control board. In particular, in the case of a capacitor with a curved lead side, the bonding of the bonding material becomes unstable, increasing the risk of the lead being damaged by vibration.

[0007] Furthermore, when applying a bonding material between the capacitor and the control board, the shape of the bonding material is difficult to stabilize and it spreads on the control board, which creates the inconvenience of having to consider the pattern design.

[0008] The present invention has been made to solve the above-mentioned conventional technical problems, and aims to provide a vibration-resistant structure for electronic components that improves the vibration resistance and productivity of electronic components, and a heat transfer medium heating device equipped with the same.

[0009] The present invention is a vibration-resistant structure for electronic components having lead portions connected to a control board, characterized in that a first electronic component having a relatively low vibration resistance and a second electronic component having a relatively higher vibration resistance than the first electronic component are mounted adjacent to each other on the control board, and a joining member is provided to join the portion of the first electronic component opposite the control board to the second electronic component.

[0010] A vibration-resistant structure for electronic components according to a second aspect of the present invention is characterized in that in the above-mentioned invention, the bonding material is a two-component curing resin.

[0011] A vibration-resistant structure for an electronic component according to a third aspect of the present invention is characterized in that the first electronic component is a capacitor.

[0012] A vibration-resistant structure for electronic components according to a fourth aspect of the present invention is characterized in that the second electronic component is a coil.

[0013] The vibration-resistant structure of an electronic component of the fifth invention is characterized in that in the present invention, a protrusion that protrudes toward the first electronic component is formed on the second electronic component, and the joining member is provided between the protrusion and the first electronic component.

[0014] The vibration-resistant structure of an electronic component of the sixth invention is characterized in that in the above invention, the second electronic component has a plurality of protrusions formed thereon, and a joining member is provided between each of the protrusions and the first electronic component.

[0015] The vibration-resistant structure of an electronic component of the seventh invention is characterized in that in the above invention, the tips of the multiple protrusions are connected by a connecting portion facing the first electronic component, and the joining member is provided between the connecting portion and the first electronic component.

[0016] The vibration-resistant structure of an electronic component of the eighth invention is characterized in that, in the fifth invention, an enlarged portion is formed at the tip of the protrusion, and the joining member is provided between the enlarged portion and the first electronic component.

[0017] The heat transfer medium heating device of the ninth invention is characterized in that it is equipped with the vibration-resistant structure of the electronic components of each of the above inventions, and further comprises a heat transfer medium flow path configured within a housing, an electric heater for heating the heat transfer medium flowing through this heat transfer medium flow path, and a control board provided within the housing and on which the various electronic components are mounted, and is mounted on a vehicle.

[0018] According to the present invention, in a vibration-resistant structure for electronic components having leads connected to a control board, when a first electronic component having a relatively low vibration resistance and a second electronic component having a relatively higher vibration resistance than the first electronic component are mounted adjacent to each other on the control board, a joining member is provided to join the portion of the first electronic component opposite the control board to the second electronic component, thereby improving the vibration resistance of the first electronic component having a low vibration resistance. This prevents the leads of the electronic component joined to the control board from being damaged by vibration, making the structure extremely suitable for vehicle-mounted heat medium heating devices such as those of the ninth invention, which require high vibration resistance.

[0019] In particular, because the bonding material connects the portion of the first electronic component opposite the control board, where the amplitude of the vibration is large, to the second electronic component, it is possible to obtain high vibration resistance with a smaller amount of bonding material than when the control board and the first electronic component are bonded with a bonding material. Furthermore, because the first electronic component is fixed to the second electronic component with the bonding material at a position away from the control board, for example, even if the bonding material drips, it is less likely to adhere to the control board, and the inconvenience of restricting the pattern design of the control board can be eliminated.

[0020] In this case, as in the second aspect of the present invention, a two-component curing resin can be used as the bonding material. In particular, the use of a two-component curing resin makes it possible to easily bond the first electronic component and the second electronic component, and after the bonding material has hardened, the bonded portions of the electronic components are not susceptible to damage due to vibration, thereby improving assembly ease and vibration resistance. Furthermore, the use of a two-component curing resin shortens the holding time until hardening, thereby improving productivity.

[0021] Furthermore, a first electronic component having a relatively low vibration resistance is, for example, a capacitor as in the third invention, and a second electronic component having a relatively high vibration resistance is, for example, a coil as in the fourth invention.

[0022] Furthermore, as in the fifth aspect of the present invention, if a protrusion that protrudes toward the first electronic component is formed on the second electronic component and a joining member is provided between this protrusion and the first electronic component, the protrusion can be placed between the second electronic component, which has relatively high vibration resistance, and the first electronic component, which has low vibration resistance, and the two electronic components can be easily fixed together by the joining member.

[0023] In this case, as in the sixth aspect of the present invention, by forming a plurality of protrusions on the second electronic component and providing a joining member between each protrusion and the first electronic component, it becomes possible to stably provide the joining member and fix the two electronic components together.

[0024] Furthermore, as in the seventh invention, if the tips of the multiple protrusions are connected by a connecting portion that faces the first electronic component and a joining member is provided between this connecting portion and the first electronic component, it becomes relatively easy to manage the position where the joining member is provided, and the joining member can join the two electronic components with a line rather than a point, making it possible to stably fix the two electronic components with a smaller amount of joining member.

[0025] Furthermore, as in the eighth aspect of the present invention, by forming a widened portion at the tip of the protrusion and providing a joining member between this widened portion and the first electronic component, it becomes relatively easy to manage the position of the joining member, and the two electronic components can be joined by a line. In this case, a single or a small number of protrusions is sufficient, and the shape of the second electronic component does not need to be changed as much.

[0026] 1 is a perspective view showing the appearance of a heat medium heating device of an embodiment to which the present invention is applied. FIG. 1 is a schematic cross-sectional plan view illustrating a flow path of a heat medium in the heat medium heating device of FIG. 1. FIG. 2 is a plan view showing the interior of the heat medium heating device of FIG. 1 (with the control board seen through). FIG. 3 is a longitudinal side view of the heat medium heating device of FIG. 1. FIG. 4 is an enlarged schematic view illustrating an attachment structure of a power switching element of the heat medium heating device of FIG. 1. FIG. 5 is a schematic enlarged view illustrating a vibration-resistant structure of a capacitor of the heat medium heating device of FIG. 1. FIG. 6 is a view of FIG. 6 from the opposite side to the control board. FIG. 7 is a circuit block diagram of a control device of the heat medium heating device of FIG. 1. FIG. 8 is an enlarged view illustrating another vibration-resistant structure of a capacitor of the heat medium heating device of FIG. 1. FIG. 9 is a view of FIG. 9 from the opposite side to the control board. FIG. 11 is an enlarged view illustrating yet another vibration-resistant structure of a capacitor of the heat medium heating device of FIG. 1.

[0027]

[0023] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 is a perspective view showing the appearance of a heat medium heating device 1 according to an embodiment of the present invention, Fig. 2 is a schematic cross-sectional plan view illustrating the flow of heat medium within the heat medium heating device 1, Fig. 3 is a plan view showing the inside of the main body 3 of the housing 2 with the cover 4 of the heat medium heating device 1 of Fig. 1 removed and the control board 21 seen through, and Fig. 4 is a vertical cross-sectional side view of the heat medium heating device 1 with the cover 4 removed.

[0028] (1) Heat Medium Heating Device 1 The heat medium heating device 1 of the embodiment is used to air-condition the interior of a vehicle (not shown), and has a housing 2 composed of a main body 3 made of a metal having high thermal conductivity, such as iron or aluminum, and a cover 4 also made of metal attached to the main body 3. The main body 3 of the housing 2 is provided with a plurality of (two in the embodiment) flow path sections 6, 7 (also made of metal) spaced apart from each other at a gap 8, which form part of the main body 3, and within which heat medium flow paths 9, 11 are respectively formed. That is, the heat medium flow paths 9, 11 are arranged side by side within the housing 2, spaced apart from each other at the gap 8.

[0029] A communication section 13 having a communication flow path 12 formed therein is connected to one end of the flow path sections 6, 7, and constitutes part of the main body 3, and one end of each of the heat medium flow paths 9, 11 is connected to this communication flow path 12. Inlet / outlet sections 16, 17 for allowing the heat medium to flow in and out are configured to be connected to the other end of each of the heat medium flow paths 9, 11, respectively.

[0030] In the following embodiment, the heat medium flows into the inlet / outlet portion 16 of one heat medium flow path 9 and flows out from the inlet / outlet portion 17 of the other heat medium flow path 11. That is, in the embodiment, the heat medium flows into the heat medium flow path 9 from the inlet / outlet portion 16, enters the heat medium flow path 11 through the communication flow path 12, and flows out from the inlet / outlet portion 17. However, depending on the installation layout of the heat medium heating device 1 on the vehicle, the heat medium may flow into the inlet / outlet portion 17 of the other heat medium flow path 11 and flow out from the inlet / outlet portion 16 of one heat medium flow path 9.

[0031] In each figure, reference numerals 18 and 19 denote rod-shaped electric heaters (heat generating elements) constituted by cartridge heaters (cylindrical heaters) in this embodiment, and electric heater (electric heater 1) 18 is inserted into one heat medium flow path 9 with a gap between it and the inner surface of flow path portion 6, while electric heater (electric heater 2) 19 is inserted into the other heat medium flow path 11 with a gap between it and the inner surface of flow path portion 7. As a result, the electric heaters 18, 19 are arranged in series with respect to the flow of the heat medium, and the communicating flow path 12 in the communicating portion 13 is located between the electric heaters 18, 19.

[0032] In this embodiment, the connection terminal 18A of the electric heater 18 is drawn out from the flow path portion 6 at one end of the heat medium flow path 9, and the connection terminal 19A of the electric heater 19 is drawn out from the flow path portion 7 at one end of the heat medium flow path 11. Sockets 43, 44 (FIG. 1) are attached to the connection terminals 18A, 19A from the outside, respectively, and are electrically connected to a control board 21 (described later) via the sockets 43, 44.

[0033] A control board 21 is attached to the main body 3 at a position on the cover 4 side of each of the flow passage sections 6, 7 so as to cover the gap 8. Mounted on this control board 21 are a power switching element 22 (IGBT1) for controlling the supply of electricity to the electric heater 18, a power switching element 23 (IGBT2) for controlling the supply of electricity to the electric heater 19, and a power switching element 24 (IGBT3) for adjusting the overall power of each of the electric heaters 18, 19. In the embodiment, the plurality of power switching elements 22 to 24 are configured as IGBTs, but they may also be configured as SICs.

[0034] Also mounted on the control board 21 are a capacitor 26 (a smoothing capacitor made of a film capacitor) as a first electronic component with relatively low vibration resistance, and a coil 27 (common mode coil) as a second electronic component with relatively high vibration resistance that constitutes the noise filter 25. The capacitor 26 and the coil 27 are electronic components that are larger in size than the power switching elements 22 to 24. The power switching elements 22 to 24, the capacitor 26, the coil 27, etc. constitute a control device 31 (FIG. 8) for controlling the electric heaters 18, 19, etc. of the heat medium heating device 1.

[0035] (2) Mounting Structure of Power Switching Elements 22-24 Next, the mounting structure of each of the power switching elements 22-24 will be described with reference to Figures 3 to 5. In this embodiment, all of the power switching elements 22-24 are arranged within the gap 8 and are mounted in a heat exchange manner with the communicating part 13 via an insulating heat transfer sheet 46. As a result, each of the power switching elements 22-24 is arranged to be able to exchange heat with the heat medium flowing in the communicating flow path 12, i.e., the heat medium flowing between the electric heaters 18 and 19.

[0036] In this embodiment, each of the power switching elements 22 to 24 is pressed against the communication portion 13 via a heat transfer sheet 46 by a fixed leaf spring 47 that is screwed to the main body 3. Also, in this embodiment, as shown enlarged in Figure 5, heat dissipation properties are improved by providing heat dissipation grease 48 around the power switching elements 22 to 24 (not shown in Figure 3). However, this heat dissipation grease 48 does not have to be provided.

[0037] In particular, as will be described later, the currents flowing through power switching element 22 (IGBT1) and power switching element 23 (IGBT2) join together and flow, and power switching element 24 (IGBT3: at least a specific power switching element) which generates the greatest amount of heat is disposed in correspondence with the center of communication flow path 12. As a result, power switching element 24 is disposed at a location where the temperature of the heat medium flowing in from inlet / outlet portion 16 and flowing out from inlet / outlet portion 17 is at the median value.

[0038] In the embodiment, the other power switching elements 22, 23 are also arranged in parallel on both sides of the power switching element 24, but this is not limiting, and the power switching elements 22 and 23 may be arranged in a heat exchange relationship with the heat medium flowing through the heat medium flow paths 9, 11 in the flow path portion 6 and the flow path portion 7. The connection terminals of each power switching element 22 to 24 (the connection terminal of the power switching element 23 is indicated by 23A in FIG. 4 and the connection terminal of the power switching element 24 is indicated by 24A in FIG. 5) are located on the control board 21 side and are electrically connected to the control board 21.

[0039] (3) Vibration-Resistant Structure of Capacitor 26 Next, the vibration-resistant structure of the capacitor (first electronic component) 26 will be described with reference to Figures 3, 4, 6, and 7. The capacitor 26 and the coil 27 are mounted adjacent to each other on the surface of the control board 21 facing the flow path sections 6 and 7, and are inserted into the gap 8 between the flow path section 6 (heat medium flow path 9) and the flow path section 7 (heat medium flow path 11) (Figures 3 and 4).

[0040] In this embodiment, the coil 27 (second electronic component), which is a common mode coil, has four lead portions 27A, one for each end of the primary and secondary windings (shown as 49P and 49S in FIG. 7 ), and each lead portion 27A is connected to the control board 21, so that the vibration resistance is relatively high. On the other hand, the lead portion 26A of the capacitor 26 (first electronic component) is also connected to the control board 21, but since there are only two of them, the vibration resistance is relatively low. In particular, when the heat medium heating device 1 is mounted on a vehicle, vibrations are likely to be applied, and while the control board 21 side of the capacitor 26 has a small amplitude, the portion opposite the control board 21 has a large amplitude in the direction perpendicular to the line connecting the two lead portions 26A.

[0041] That is, the coil 27 has higher vibration resistance than the capacitor 26. Therefore, the capacitor 26 is first placed near the coil 27, and the coil 27 is placed in a direction in which the line connecting the two lead portions 26A of the capacitor 26 intersects at right angles. Meanwhile, the coil 27 typically includes a core (not shown) and a hard resin case 51 that houses the core, and the windings 49P and 49S are wound around the periphery of the case 51. In this embodiment, a plurality of (two in this embodiment) protrusions 52 and 53 are formed integrally with the case 51.

[0042] These protrusions 52, 53 protrude from the coil 27 towards the capacitor 26, and their tips abut against or are close to the capacitor 26. A joining member 54 is provided between each of these protrusions 52, 53 and the portion of the capacitor 26 opposite the control board 21, to join the capacitor 26 and the coil 27. In this embodiment, this joining member 54 is made of a two-component curing resin such as epoxy resin, and is applied between each of the protrusions 52, 53 and the capacitor 26.

[0043] (4) Control Device 31 Next, Fig. 8 shows a circuit block of the control device 31. The coil 27 that constitutes the noise filter 25 described above is connected to the vehicle battery (DC power source) (not shown), and the capacitor 26 is connected downstream of this coil 27. The power switching element 22 and the electric heater 18 are connected in series, and the power switching element 23 and the electric heater 19 are connected in series, with these two series circuits being connected in parallel. The power switching element 24 is connected in series to these parallel circuits, and a current sensor 32 is connected in series to the power switching element 24.

[0044] The power switching elements 22 and 23 are connected to the positive electrode side of the capacitor 26, and the current sensor 32 is connected to the negative electrode side. As a result, the currents that flow through the two power switching elements 22 and 23 join together and flow through the power switching element 24.

[0045] 8, reference numeral 36 denotes a control unit configured by a microcomputer, and drivers 37, 38, and 39 are connected to the output of this control unit 36. Driver 37 is connected to the gate of power switching element 22, and driver 38 is connected to the gate of power switching element 23. Driver 39 is connected to the gate of power switching element 24.

[0046] The control unit 36 ​​receives the output of the current sensor 32, as well as the outputs of the inlet temperature sensor 41 and the outlet temperature sensor 42. In this embodiment, the inlet temperature sensor 41 detects the temperature of the heat medium flowing into the heat medium flow path 9 from the inlet / outlet portion 16, and the outlet temperature sensor 42 detects the temperature of the heat medium flowing out from the inlet / outlet portion 17. In this application, the heat medium flowing in from the inlet / outlet portion 16 means the heat medium just before or just after entering the inlet / outlet portion 16, and the heat medium flowing out from the inlet / outlet portion 17 means the heat medium just before or just after exiting the inlet / outlet portion 17.

[0047] (5) Operation of Heat Medium Heating Device 1 With the above configuration, next we will explain the operation of the heat medium heating device 1. The inlet / outlet portion 16 is connected to a heat medium circuit (not shown), and a heat medium (water in this embodiment) flows into the heat medium flow path 9 from the inlet / outlet portion 16 by a pump (not shown). The heat medium that has flowed into the heat medium flow path 9 flows into the heat medium flow path 11 via the communication flow path 12, and then flows out of the inlet / outlet portion 17 into the heat medium circuit described above.

[0048] Meanwhile, the control unit 36 ​​of the control device 31 controls the switching of the power switching elements 22 to 24 using the drivers 37 to 39 based on the outputs of the inlet temperature sensor 41, the outlet temperature sensor 42, and the current sensor 32. As a result, the electric heaters 18, 19 are energized and generate heat, so that the heat medium that has flowed into the heat medium flow path 9 is heated as it passes around the electric heater 18, enters the heat medium flow path 11 via the communication flow path 12, and is further heated as it passes around the electric heater 19.

[0049] A heater core disposed in the HV unit of the vehicle is connected to the heat medium circuit, and the heat medium heated by the heat medium heating device 1 is circulated through this heater core. Air supplied to the vehicle cabin is passed through the heater core, thereby heating the cabin.

[0050] The control unit 36 ​​controls the switching of the power switching elements 22, 23 based on the temperature of the inflowing heat medium detected by the inlet temperature sensor 41 and the temperature of the outflowing heat medium detected by the outlet temperature sensor 42, and controls the supply of electricity to each of the electric heaters 18, 19. The currents flowing through these power switching elements 22, 23 (electric heaters 18, 19) join together and flow to a power switching element (specific power switching element) 24. The control unit 36 ​​controls the switching of the power switching element 24 based on the value of this joined current detected by the current sensor 32, and adjusts the overall power of each of the electric heaters 18, 19.

[0051] Here, the currents flowing through the power switching elements 22 and 23 are joined together and flow through the power switching element 24 (specific power switching element), so the power switching element 24 generates more heat than the power switching elements 22 and 23, and the amount of heat generated becomes the largest.

[0052] (6) Effects of Arrangement of Heat Medium Flow Paths 9, 11, Communication Flow Path 12, and Power Switching Elements 22-24 As described above, the plurality of power switching elements 22-24 are arranged between the plurality of electric heaters 18, 19. This allows the dead space between the electric heaters 18, 19 to be effectively utilized for arranging the plurality of power switching elements 22-24, thereby enabling the heat medium heating device 1 to be made smaller.

[0053] In particular, in this embodiment, the power switching elements 22 to 24 are arranged so as to be able to exchange heat with the heat medium flowing between the plurality of electric heaters 18, 19 arranged in series with respect to the flow of the heat medium, so that, unlike the above-described embodiment, even if the flow of the heat medium is reversed in the layout of the heat medium heating device 1 into the vehicle, such that the heat medium flows in from the inlet / outlet section 17 and flows out from the inlet / outlet section 16, the appropriate temperature can be maintained without changing the positions of the power switching elements 22 to 24. This improves the versatility of the layout of the heat medium heating device 1.

[0054] In this embodiment, among the plurality of power switching elements 22 to 24, a specific power switching element 24 that generates more heat than the others is arranged so that it can exchange heat with the heat medium flowing through the communication flow path 12 between the plurality of electric heaters 18, 19 that are arranged in series with the flow of the heat medium. Therefore, even if the flow of the heat medium is reversed, the power switching element 24 that generates more heat can be cooled efficiently and reliably.

[0055] This makes it possible to maintain all of the power switching elements 22 to 24 in an appropriate temperature range, and prevents breakdowns in the power switching elements 22 to 24.

[0056] Furthermore, in the embodiment, the connection terminals 18A, 19A of the electric heaters 18, 19 are drawn out from one end of the heat medium flow paths 9, 11, and the plurality of power switching elements 22 to 24 are arranged so as to be able to exchange heat with the heat medium flowing through the communication flow path 12, so that the electrical connection positions of the electric heaters 18, 19 and the plurality of power switching elements 22 to 24 are close to each other. This allows the connection terminals 18A, 19A of the electric heaters 18, 19 and the plurality of power switching elements 22 to 24 to be electrically connected to the control board 21 in close positions, improving the design freedom of the wiring pattern of the control board 21.

[0057] (7) Effect of the vibration-resistant structure of the capacitor 26 Furthermore, the capacitor 26 (first electronic component), which has a relatively low vibration resistance, and the coil 27 (second electronic component), which has a relatively higher vibration resistance than the capacitor 26, are mounted adjacent to each other on the control board 21, and a joining member 54 is provided to join the part of the capacitor 26 opposite the control board 21 to the coil 27, thereby making it possible to improve the vibration resistance of the capacitor 26, which has a low vibration resistance.

[0058] 6, it is possible to reduce the amplitude of the capacitor 26 at the portion opposite to the control board 21. This makes it possible to prevent the lead portion 26A of the capacitor 26, which is joined to the control board 21, from being damaged by vibration, making it extremely suitable for the vehicle-mounted heat medium heating device 1, which requires high vibration resistance.

[0059] In particular, because the portion of capacitor 26 opposite control board 21 where the amplitude of vibration is large is joined to coil 27 by joining member 54, it is possible to obtain high vibration resistance with a smaller amount of joining member 54 than when joining control board 21 and capacitor 26 with joining member 54. Furthermore, because capacitor 26 is fixed to coil 27 by joining member 54 at a position away from control board 21, even if joining member 54 made of two-component curing resin drips as in the embodiment, it is less likely to adhere to control board 21, and the inconvenience of restrictions on the pattern design of control board 21 can be eliminated.

[0060] In particular, in the embodiment, a two-component curing resin is used as the joining member 54, which makes it easy to join the capacitor 26 and the coil 27, and after the joining member 54 hardens, the joint between the capacitor 26 and the coil 27 will not be damaged by vibration, improving assembly ease and vibration resistance. Furthermore, the use of a two-component curing resin shortens the holding time until hardening, thereby improving productivity.

[0061] In addition, in the embodiment, multiple protrusions 52, 53 are formed on the coil 27 that protrude toward the capacitor 26, and a joining member 54 is provided between each of the protrusions 52, 53 and the capacitor 26.Therefore, the protrusions 52, 53 can be placed between the coil 27, which has relatively high vibration resistance, and the capacitor 26, which has low vibration resistance, and the capacitor 26 and the coil 27 can be easily and stably fixed together by the joining member 54.

[0062] (8) Another Example of the Vibration-Resistant Structure of the Capacitor 26 Next, another example of the vibration-resistant structure of the capacitor (first electronic component) 26 will be described with reference to Figures 9 and 10. In each figure, the same reference numerals as in Figures 6 and 7 denote the same or similar functions. In this example, the tips of the two protrusions 52, 53 in Figures 6 and 7 are connected by a connecting portion 56. This connecting portion 56 is then placed opposite (in contact with or close to) the capacitor 26, and a bonding material 54 is applied between this connecting portion 56 and the capacitor 26.

[0063] With this configuration, it becomes relatively easy to manage the application position of the joining member 54, and the joining member 54 can join the capacitor 26 and the coil 27 with a line rather than a point, making it possible to stably fix the capacitor 26 and the coil 27 with a smaller amount of joining member 54.

[0064] (9) Another Example of the Vibration-Resistant Structure of the Capacitor 26 Next, another example of the vibration-resistant structure of the capacitor 26 will be described with reference to Figures 11 and 12. In each figure, the same reference numerals as in Figures 6, 7, 9, and 10 denote the same or similar functions. In this example, one protrusion 57 protrudes from the case 51 of the coil 27 toward the capacitor 26.

[0065] 12, a widened portion 58 is formed at the tip of the protrusion 57. The widened portion 58 is also located close to or in contact with the capacitor 26 and faces the capacitor 26. A joining member 54 is provided between the widened portion 58 and the capacitor 26.

[0066] Even with this configuration, it is relatively easy to manage the application position of the joining material 54, and it is possible to join the capacitor 26 and the coil 27 with a wire by the joining material 54. In particular, in this case, a single protrusion 57 or a smaller number of protrusions than in the examples of Figures 6 and 9 is sufficient, so the shape of the case 51 of the coil 27 does not need to be changed as much.

[0067] In the embodiment, the capacitor 26 is used as the first electronic component having a relatively low vibration resistance, and the coil 27 is used as the second electronic component having a relatively high vibration resistance. However, the present invention is not limited to this, and other combinations of electronic components are also effective within the scope of the present invention.

[0068] In addition, in the embodiment, the inlet temperature sensor 41 and the outlet temperature sensor 42 are provided to control the power supply to the electric heaters 18, 19, but control may be performed using only the inlet temperature sensor 41, or only the outlet temperature sensor 42, or a temperature sensor that detects the temperature (median value) of the heat medium flowing through the communicating flow path 12.

[0069] Furthermore, in the embodiment, an example having two heat medium flow paths 9 and 11 has been described, but the present invention is also effective when more heat medium flow paths are configured and arranged at a distance from each other. Also, in the embodiment, the power switching elements 22 to 24 are configured as IGBTs, but they may also be configured as MOSFETs, SICs, etc.

[0070] Furthermore, in the embodiment, a heat medium heating device used for air conditioning of a vehicle has been taken up as an example for explanation, but the present invention is not limited to this and is effective for heat medium heating devices in various heating systems.

[0071] REFERENCE SIGNS LIST 1 Heat medium heating device 2 Housing 8 Spacing 9, 11 Heat medium flow path 12 Communication flow path 16, 17 Inlet / outlet portion 18, 19 Electric heater 21 Control board 22 to 24 Power switching element 26 Capacitor (first electronic component) 26A, 27A Lead portion 27 Coil (second electronic component) 31 Control device 32 Current sensor 36 Control unit 41 Inlet temperature sensor 42 Outlet temperature sensor 52, 53, 57 Protrusion 54 Joint member 56 Connecting portion 58 Widened portion

Claims

1. A vibration-resistant structure for electronic components having leads connected to a control board, wherein a first electronic component having a relatively low vibration resistance and a second electronic component having a relatively higher vibration resistance than the first electronic component are mounted adjacent to each other on the control board, and a joining member is provided to join the part of the first electronic component opposite the control board to the second electronic component.

2. The vibration-resistant structure for electronic components according to claim 1, wherein the bonding material is a two-component curing resin.

3. The vibration-resistant structure for electronic components according to claim 1, wherein the first electronic component is a capacitor.

4. The vibration-resistant structure for electronic components according to claim 1, wherein the second electronic component is a coil.

5. The vibration-resistant structure of an electronic component described in claim 1, characterized in that the second electronic component is formed with a protruding portion that protrudes toward the first electronic component, and the joining member is provided between the protruding portion and the first electronic component.

6. A vibration-resistant structure for electronic components as described in claim 5, characterized in that a plurality of protrusions are formed on the second electronic component, and the joining member is provided between each of the protrusions and the first electronic component.

7. A vibration-resistant structure for electronic components as described in claim 6, characterized in that the tips of the multiple protrusions are connected by a connecting portion that faces the first electronic component, and the joining member is provided between the connecting portion and the first electronic component.

8. A vibration-resistant structure for electronic components as described in claim 5, characterized in that an enlarged portion is formed at the tip of the protrusion, and the joining member is provided between the enlarged portion and the first electronic component.

9. A heat medium heating device having a vibration-resistant structure for electronic components according to any one of claims 1 to 8, characterized in that it comprises a heat medium flow path configured within a housing, an electric heater that heats the heat medium flowing through the heat medium flow path, and a control board that is provided within the housing and on which each of the electronic components is mounted, and is installed in a vehicle.

Images