Electric connection box

Abstract

To provide an electric connection box that can more reliably suppress the influence of heat generated by heat-generating components on low heat-resistant components.SOLUTION: An electric connection box 10 has a case 20 and a first circuit board 311 that is housed in a housing space S2 in the case 20 and on which heat-generating components 321 are mounted. The electric connection box 10 also has a second circuit board 312 that is housed in the housing space S2 and on which low heat-resistant components 322, which have lower heat resistance than the heat-generating components 321, are mounted. Furthermore, the electric connection box 10 has a thermal conduction suppression portion 80 that is interposed between the heat-generating component 321 and the low heat-resistant component 322 to suppress the transfer of heat generated by the heat-generating component 321 to the low heat-resistant component 322.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an electrical junction box. [Background technology]

[0002] A conventional electrical connection box of this type is disclosed in Patent Document 1. Patent Document 1 discloses an electrical connection box including a circuit board. The circuit board includes a first circuit board on which a load circuit section including a relay, a driving IC, and a conductor pattern is formed, and a second circuit board on which a control circuit section including a microcomputer, a connector section, and a conductor pattern is formed.

[0003] In this manner, in Patent Document 1, components with a relatively large current capacity, such as the load circuit section, are concentrated on the first circuit board, and components with a relatively small current capacity, such as the control circuit section, are concentrated on the second circuit board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-267596 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, since a relatively large current flows through the load circuit, a relatively large current also flows through the relay and other components that constitute a part of the load circuit, and therefore the relay and other components that constitute a part of the load circuit are heat-generating components that are prone to generating heat.

[0006] On the other hand, the microcomputer and the like constituting a part of the control circuit are generally formed using components that have lower heat resistance than heat-generating components such as relays, that is, low-heat-resistant components.

[0007] Therefore, in the electrical junction box shown in the above-mentioned prior art, heat-generating components and low heat-resistant components are mounted on the circuit board.

[0008] In this manner, when heat-generating components and low heat-resistant components are mounted on a circuit board, it is preferable to prevent the low heat-resistant components from being affected by the heat generated by the heat-generating components.

[0009] The present invention has been made in consideration of the problems inherent in the conventional technology, and an object of the present invention is to provide an electrical junction box capable of more reliably preventing low heat resistant components from being affected by heat generated by heat generating components. [Means for solving the problem]

[0010] An electrical junction box according to one embodiment of the present invention comprises a case, a first circuit board housed in an accommodation space within the case and carrying a heat-generating component, a second circuit board housed in the accommodation space and carrying a low heat-resistant component having a lower heat resistance than the heat-generating component, and a heat conduction suppression portion interposed between the heat-generating component and the low heat-resistant component and suppressing the transfer of heat generated by the heat-generating component to the low heat-resistant component. Effect of the Invention

[0011] According to the present invention, it is possible to provide an electric junction box that can more reliably prevent low heat resistant components from being affected by heat generated by heat generating components. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view showing a schematic example of a method of arranging the ECU-equipped electric junction box according to the first embodiment. [Diagram 2] 1 is a perspective view showing a schematic diagram of an ECU-equipped electric junction box according to a first embodiment; [Diagram 3] FIG. 2 is an exploded perspective view showing a schematic diagram of the ECU-equipped electric junction box according to the first embodiment; [Figure 4]FIG. 1 is a diagram showing an example of an electrical junction box according to a first embodiment, and is a perspective view of an assembled state of the electrical junction box as viewed from one direction. [Diagram 5] FIG. 4 is a diagram showing an example of the electrical junction box according to the first embodiment, being a perspective view seen from another direction with the fuse cover open. [Figure 6] FIG. 1 is a diagram showing an example of an electrical junction box according to a first embodiment, and is an exploded perspective view of the electrical junction box as viewed from one direction. [Figure 7] 1 is a cross-sectional view showing a schematic example of an electrical junction box according to a first embodiment. [Figure 8] 4 is a cross-sectional view illustrating a schematic diagram of another example of the electrical junction box according to the first embodiment. FIG. [Figure 9] FIG. 11 is a diagram showing an example of an electric junction box according to a second embodiment, and is a perspective view of an assembled state of the electric junction box as viewed from one direction. [Figure 10] FIG. 11 is a diagram showing an example of an electrical junction box according to a second embodiment, and is an exploded perspective view of the electrical junction box as viewed from one direction. [Figure 11] FIG. 6 is a cross-sectional view illustrating an example of an electrical junction box according to a second embodiment. [Figure 12] FIG. 11 is a cross-sectional view that illustrates a first modified example of the electrical junction box according to the second embodiment. [Figure 13] FIG. 13 is a diagram showing a second modified example of the electrical junction box according to the second embodiment, and is an exploded perspective view of the electrical junction box as viewed from one direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the electrical junction box according to the present embodiment will be described in detail with reference to the drawings. Note that the dimensional ratios in the drawings are exaggerated for the convenience of explanation and may differ from the actual ratios.

[0014] In the following, when describing each component of the electrical junction box, the up-down direction of the electrical junction box will be defined with the side on which the body ECU is arranged facing upward.

[0015] In addition, the following embodiments and their modified examples include similar components, and therefore, in the following, the similar components are given the same reference numerals and redundant explanations are omitted.

[0016] (First embodiment) The electrical connection box 10 in this embodiment is also called a junction block (J / B), and is a device for distributing and supplying current supplied from a battery or alternator mounted on a vehicle or the like to an ECU (Electrical Control Unit) 110 mounted on the vehicle or the like.

[0017] The electric junction box 10 can be installed, for example, in an instrument panel formed in a vehicle together with a plurality of ECUs 110 having various control functions. The plurality of ECUs 110 are formed with circuits for controlling various vehicle systems, such as air conditioner control and ABS (Anti-lock Brake System) control.

[0018] In recent years, the electrification and automation of vehicles has progressed, and as the electrification and automation of vehicles progresses, the number of ECUs 110 mounted in the vehicles etc. is also increasing. On the other hand, there is also a demand to ensure sufficient interior space in the vehicle, so it is becoming difficult to ensure sufficient installation space for the electric junction box 10 and the ECU 110 in the vehicle.

[0019] Therefore, there is a demand for making it possible to arrange more devices (electrical junction boxes 10 and ECUs 110) in a limited space.

[0020] Therefore, in this embodiment, an electrical junction box 1 with an ECU is formed by integrating the electrical junction box 10 and the body ECU 120, and this electrical junction box 1 with an ECU is installed on an instrument panel formed on the vehicle.

[0021] 1, for example, this ECU-equipped electric junction box 1 can be installed in an instrument panel hose 100 that reinforces an instrument panel together with a plurality of ECUs 110. In this way, by arranging a plurality of ECUs 110 and ECU-equipped electric junction boxes 1 in a closely packed line, it becomes possible to arrange more devices (electrical junction boxes 10 and ECUs 110) in the limited space inside the vehicle.

[0022] At this time, the ECU-equipped electrical junction box 1 is installed on the instrument panel hose 100 in a state in which a fuse cover 64, which will be described later, is positioned on the opposite side (the lower side in FIG. 1) from the instrument panel hose 100. This makes it possible to remove, open, and close the fuse cover 64 without removing the ECU-equipped electrical junction box 1 from the instrument panel hose 100.

[0023] The installation method of the ECU-equipped electrical junction box 1 is not limited to the method shown in FIG. 1, and the ECU-equipped electrical junction box 1 can be installed in various ways (various locations and various postures).

[0024] 2 and 3, the present embodiment illustrates an electric junction box 10 having an accommodating recess S1 to which the body ECU 120 can be detachably attached. The body ECU 120 is detachably fitted into the accommodating recess S1 formed in the electric junction box 10 to form the ECU-equipped electric junction box 1. The method of forming the ECU-equipped electric junction box 1 is not limited to the method shown in FIGS. 2 and 3, and various other methods are possible.

[0025] The body ECU 120 attached to the electrical junction box 10 may be, for example, a device having a circuit for controlling a system inside the vehicle, such as door lock control.

[0026] Next, a specific configuration of the electrical junction box 10 according to this embodiment will be described with reference to FIGS.

[0027] In this embodiment, the electrical junction box 10 includes a case 20, a circuit block 30, a body ECU connector 40, a wire harness connector 50, and a fuse block 60.

[0028] Specifically, the case 20 is a member that constitutes the outer shell of the electric junction box 10, and an accommodation space S2 is formed inside the case 20.

[0029] In addition, various circuits are formed in the circuit block 30, such as a circuit having the function of distributing current supplied from the battery and alternator, and a control circuit, and this circuit block 30 is housed within the housing space S2 of the case 20.

[0030] The body ECU connector 40 is configured to fit into a connector portion (not shown) of the body ECU 120 when the body ECU 120 is attached to the electric junction box 10. By fitting the body ECU connector 40 into the connector of the body ECU 120, a part of the circuits formed in the circuit block 30 is electrically connected to a control circuit formed in the body ECU 120. In this manner, the body ECU connector 40 is a member for electrically connecting the circuit block 30 to the control circuit of the body ECU 120. In this embodiment, the body ECU connector 40 is accommodated in the accommodation space S2 with a part of it exposed to the outside of the case 20.

[0031] The wire harness connector 50 is a member into which a connector portion of a wire harness (not shown) is fitted to electrically connect the wire harness to some of the circuits formed in the circuit block 30. In this embodiment, the wire harness connector 50 is also accommodated in the accommodation space S2 with a portion of the wire harness connector 50 exposed to the outside of the case 20.

[0032] The fuse block 60 is a component for cutting off current when an overcurrent flows through a circuit formed in the circuit block 30, and this fuse block 60 is also housed within the housing space S2 with a portion of it exposed to the outside of the case 20.

[0033] As shown in FIG. 6, the case 20 includes an upper case 21 and a lower case 22, and by assembling the upper case 21 to the lower case 22, the case 20 is formed with an accommodation space S2 formed therein.

[0034] Specifically, the upper case 21 includes a top wall 211 and a peripheral wall 212 that is connected to the peripheral portion of the top wall 211 so as to extend downward. The lower case 22 includes a bottom wall 221 and a peripheral wall 222 that is connected to the peripheral portion of the bottom wall 221 so as to extend upward. The upper case 21 is assembled to the lower case 22 in a state in which the lower end of the peripheral wall 212 is butted against the upper end of the peripheral wall 222, thereby forming a case 20 having an accommodation space S2 formed therein. In this embodiment, when the upper case 21 is assembled to the lower case 22, an engagement portion 2221 formed on the peripheral wall 222 of the lower case 22 is engaged with an engagement portion (not shown) formed on the peripheral wall 212 of the upper case 21.

[0035] A first insertion hole 211a and a second insertion hole 211b are formed in the top wall 211 of the upper case 21 so as to penetrate in the up-down direction. When the various components are assembled to form the electric junction box 10, the body ECU connector 40 is inserted into the first insertion hole 211a so that an upper portion of the body ECU connector 40 is exposed to the outside of the case 20. A fusible link 632, which will be described later, is removably inserted into the second insertion hole 211b.

[0036] Furthermore, three notches (notch 212a, notch 212b, notch 212c) are formed in the peripheral wall 212 of the upper case 21, so that a storage space S2 that is open in three directions is formed in a state in which the upper case 21 is assembled to the lower case 22. That is, the storage space S2 is a space in which a first opening S2a, a second opening S2b, and a third opening S2c are formed.

[0037] An input wire harness connector 51 of the wire harness connector 50, which will be described later, is accommodated in the accommodation space S2 with a portion thereof exposed from the first opening S2a. An output wire harness connector 52 of the wire harness connector 50, which will be described later, is accommodated in the accommodation space S2 with a portion thereof exposed from the second opening S2b. And a fuse block 60 is accommodated in the accommodation space S2 with a portion thereof exposed from the third opening S2c.

[0038] Furthermore, in this embodiment, the upper case 21 is formed with an extension wall 213 that is connected to and extends upward from the peripheral portion of the top wall 211, and this extension wall 213 defines an accommodating recess S1 into which the body ECU 120 is fitted.

[0039] Moreover, the circuit block 30 includes a circuit board 31 and mounted components 32 mounted on the circuit board 31. The mounted components 32 are mounted on the circuit board 31 and electrically connected to a conductor pattern formed on the circuit board 31, so that the mounted components 32 and the conductor pattern form a part of each circuit.

[0040] Here, in this embodiment, circuit block 30 has a circuit for current distribution and a circuit for control, and circuit board 31 includes first circuit board 311 and second circuit board 312. Then, the circuit for current distribution is mainly formed on first circuit board 311, and the circuit for control is mainly formed on second circuit board 312.

[0041] In this manner, in this embodiment, components with relatively large current capacities, such as current distribution circuits, are concentrated on the first circuit board 311, and components with relatively small current capacities, such as control circuits, are concentrated on the second circuit board 312.

[0042] The current distribution circuit is formed using mounted components 32 such as relays, and the control circuit is formed using mounted components 32 such as control chips. Since a relatively large current flows through the current distribution circuit, a relatively large current also flows through the relays and the like that constitute a part of the current distribution circuit. For this reason, the relays and the like that constitute a part of the current distribution circuit are heat-generating components 321 that are prone to generating heat.

[0043] On the other hand, since there is no need to pass a large current through the control circuit, the mounted components 32 constituting a part of the control circuit include low heat resistant components 322 that have lower heat resistance than heat generating components 321 such as relays. For example, a control chip is a component that is easily affected by heat, and is the low heat resistant component 322.

[0044] Therefore, in this embodiment, heat generating components 321 such as relays used in the current distribution circuit are mainly mounted on the first circuit board 311, and low heat resistant components 322 such as control chips used in the control circuit are mainly mounted on the second circuit board 312. In this manner, thermal interference between the heat generating components 321 mounted on the first circuit board 311 and the low heat resistant components 322 mounted on the second circuit board 312 is suppressed.

[0045] Furthermore, in this embodiment, the circuit block 30 is provided with a pin header 33, which enables the second circuit board 312 to be held at a predetermined distance from the first circuit board 311.

[0046] This pin header 33 includes a housing 331 and a plurality of connection pins 332 held by the housing 331. The housing 331 holds the first circuit board 311, while the plurality of connection pins 332 electrically connect a circuit on the first circuit board 311 side to a circuit on the second circuit board 312 side. The plurality of connection pins 332 are fixed to the first circuit board 311 using solder or the like.

[0047] The body ECU connector 40 also includes a housing 41 and a plurality of connection pins 42 held by the housing 41. The housing 41 is fixed to the first circuit board 311 by screws 70. The plurality of connection pins 42 are electrically connected to the circuit of the first circuit board 311. In this manner, the body ECU connector 40 is held in a state in which it is electrically connected to the first circuit board 311. The plurality of connection pins 42 are also fixed to the first circuit board 311 by using solder or the like.

[0048] The wire harness connector 50 also includes an input wire harness connector 51 to which a wire harness connected to a battery or an alternator is connected, and an output wire harness connector 52 to which a wire harness connected to a control circuit of each ECU 110 is connected.

[0049] The input side wire harness connector 51 and the output side wire harness connector 52 are held by the first circuit board 311, respectively.

[0050] Specifically, the input side wire harness connector 51 includes an input side housing 511 and a plurality of input side connection pins 512 held by the input side housing 511. The input side housing 511 is fixed to the first circuit board 311 by screws 70. Furthermore, the plurality of input side connection pins 512 are electrically connected to the circuit of the first circuit board 311. In this manner, the input side wire harness connector 51 is held in a state in which it is electrically connected to the first circuit board 311. The plurality of input side connection pins 512 are also fixed to the first circuit board 311 by using solder or the like.

[0051] Similarly, the output-side wire harness connector 52 includes an output-side housing 521 and a plurality of output-side connection pins 522 held by the output-side housing 521. The output-side housing 521 is fixed to the first circuit board 311 by screws 70. Furthermore, the plurality of output-side connection pins 522 are electrically connected to the circuit of the first circuit board 311. In this manner, the output-side wire harness connector 52 is held in a state in which it is electrically connected to the first circuit board 311. The plurality of output-side connection pins 522 are also fixed to the first circuit board 311 by using solder or the like.

[0052] The fuse block 60 also includes a housing 61 having a plurality of fuse accommodating spaces S3 formed therein, a fuse 63 that can be inserted and held in the fuse accommodating space S3, and a connection pin 62 that is electrically connected to the fuse 63.

[0053] The housing 61 is fixed to the first circuit board 311 by screws 70. Furthermore, the connection pins 62 are electrically connected to the circuit of the first circuit board 311. In this manner, the fuse block 60 is held in a state of being electrically connected to the first circuit board 311, and a circuit with a fuse function is formed on the first circuit board 311. The multiple connection pins 62 are also fixed to the first circuit board 311 using solder or the like.

[0054] Furthermore, in this embodiment, the fuse 63 includes a plurality of mechanical fuses 631 and a plurality of fusible links 632, and each mechanical fuse 631 is removably inserted into the corresponding fuse accommodating space S3. Meanwhile, the fusible link 632 is removably inserted into the second insertion hole 211b formed in the top wall 211 of the upper case 21, as described above.

[0055] Here, when the fuse block 60 is attached to the case 20, the mechanical fuse 631 inserted into the fuse accommodating space S3 is arranged with its surface exposed to the outside of the case 20. This makes it possible to individually remove and replace the mechanical fuses 631 from the housing 61 with the electrical junction box 10 installed.

[0056] In this embodiment, the fuse block 60 is provided with a fuse cover 64. During normal use of the electrical junction box 10 (when the mechanical fuse 631 is not removed, etc.), the exposed portion of the mechanical fuse 631 is covered by the fuse cover 64. This makes it possible to prevent the mechanical fuse 631 from coming off the housing 61 during normal use of the electrical junction box 10.

[0057] In this embodiment, the fuse cover 64 is attached to the housing 61 so as to be openable and closable, as shown in Fig. 5. Specifically, an engagement hole 6412 is provided in the cover body 641 of the fuse cover 64, and a hooking claw 611 provided on the housing 61 is inserted into the engagement hole 6412 to engage with it. This allows the cover body 641 to be rotated around the engagement hole 6412 side as an axis. In this embodiment, a claw portion 6411 for hanging a finger is formed at the end of the cover body 641 opposite to the side where the engagement hole 6412 is formed, and by hooking a finger on the claw portion 6411, the cover body 641 can be easily rotated in the opening direction.

[0058] 7, the current supplied to input side connection pin 512 is supplied to a circuit formed on second circuit board 312 through a circuit formed on first circuit board 311 and connection pin 332. The current supplied to the circuit formed on second circuit board 312 is supplied to each control circuit of ECU 110 through connection pin 332, a circuit formed on first circuit board 311, and output side connection pin 522.

[0059] Here, in this embodiment, it is possible to more reliably prevent thermal interference between heat-generating components 321 mounted on first circuit board 311 and low heat-resistant components 322 mounted on second circuit board 312.

[0060] Specifically, the electrical connection box 10 is provided with a heat conduction suppression section 80 that is interposed between a heat generating component (relay, etc.) 321 and a low heat resistant component (control chip, etc.) 322 and suppresses the transfer of heat generated in the heat generating component (relay, etc.) 321 to the low heat resistant component (control chip, etc.) 322.

[0061] In this manner, the heat conduction suppression section 80 prevents the heat generated by the heat-generating component 321 mounted on the first circuit board 311 from being transferred to the low heat-resistant component 322 mounted on the second circuit board 312.

[0062] This prevents the heat generated by the heat generating component 321 from being transferred to the low heat resistant component 322, that is, prevents thermal interference between the heat generating component 321 and the low heat resistant component 322. As a result, it is possible to more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat generating component 321.

[0063] Furthermore, if the thermal interference between the heat-generating component 321 and the low heat-resistant component 322 is suppressed by the heat conduction suppression section 80, it becomes possible to mount many components on the circuit board and pass a larger current than before, without changing the size of the electrical junction box 10. In other words, even if a higher-density circuit board (circuit block 30) is mounted while keeping the size of the electrical junction box 10 the same or smaller than before, it becomes possible to keep the temperature rise of the electrical junction box 10 low.

[0064] In this embodiment, the low heat resistant component 322 mounted on the second circuit board 312 is covered with a resin coating portion 81, and this resin coating portion 81 functions as a heat conduction suppressing portion 80. Such a resin coating portion 81 can be formed using a potting resin such as a urethane resin, an epoxy resin, or a silicone resin. Specifically, in a state where the mounted components 32 such as the low heat resistant component 322 are mounted on the second circuit board 312, the potting resin can be poured so as to cover at least the low heat resistant component 322 and then hardened, thereby forming the resin coating portion 81.

[0065] The process of forming resin coating portion 81 on second circuit board 312 is performed before second circuit board 312 is accommodated in case 20. Therefore, in this embodiment, electric junction box 10 is assembled by accommodating second circuit board 312 with resin coating portion 81 formed thereon in case 20.

[0066] Thus, in this embodiment, the electrical connection box 10 further includes a resin coating portion 81 that covers the low heat resistant component 322 mounted on the second circuit board 312, and this resin coating portion 81 constitutes at least a part of the heat conduction suppression portion 80.

[0067] In this embodiment, all of the mounted components 32 mounted on the second circuit board 312 are covered with the resin coating portion 81. This allows the accommodation space S2 to be partitioned into a first accommodation space S21 in which the heat-generating components 321 mounted on the first circuit board 311 are present, and a second accommodation space S22 in which the low heat-resistant components 322 mounted on the second circuit board 312 are present.

[0068] In this way, the first accommodation space S21, which accommodates the first circuit board 311 on which the heat-generating components 321 are mainly mounted, and the second accommodation space S22, which accommodates the second circuit board 312 on which the low heat-resistant components 322 are mainly mounted, are separated by the heat conduction suppression section 80. Therefore, the transfer of heat between the first accommodation space S21 and the second accommodation space S22 is suppressed by the heat conduction suppression section 80.

[0069] In this way, by being able to suppress the transfer of heat from the space housing first circuit board 311 to the space housing second circuit board 312, it becomes possible to more reliably suppress the low heat resistant component 322 from being affected by the heat generated by heat-generating component 321.

[0070] Furthermore, with the configuration shown in this embodiment, simply by forming the resin coating portion 81, it is possible to more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat generating component 321. Therefore, it is not necessary to separately provide the cover 23 or to change the shape of the case body 200 (case 20). As a result, it is possible to more easily and at low cost obtain the electric junction box 10 that can more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat generating component 321.

[0071] The electric junction box 10 may have a configuration as shown in FIG.

[0072] In the electric junction box 10 shown in FIG. 8, all of the mounted components 32 mounted on the second circuit board 312 are also covered with the resin coating portion 81.

[0073] Here, in the electrical connection box 10 shown in Figure 8, among the multiple input side connection pins 512 of the input side wire harness connector 51, the input side connection pin 512 for supplying current to the circuit formed on the second circuit board 312 is directly fixed to the second circuit board 312.

[0074] In addition, among the multiple output side connection pins 522 of the output side wire harness connector 52, the output side connection pin 522 for introducing current from the circuit formed on the second circuit board 312 is fixed directly to the second circuit board 312.

[0075] This allows current to flow through the circuit formed on second circuit board 312 without passing through first circuit board 311. This makes it possible to prevent current flowing through the circuit formed on second circuit board 312 from flowing through first circuit board 311. Therefore, generation of heat in first circuit board 311 due to current flowing through the circuit formed on second circuit board 312 is suppressed, and it becomes possible to suppress an increase in temperature of first circuit board 311.

[0076] Second embodiment The electric junction box 10 according to this embodiment has a configuration basically similar to that of the electric junction box 10 shown in the first embodiment. That is, the electric junction box 10 according to this embodiment also includes a case 20 and a first circuit board 311 that is accommodated in the accommodation space S2 in the case 20 and has a heat generating component (relay, etc.) 321 mounted thereon. The electric junction box 10 also includes a second circuit board 312 that is accommodated in the accommodation space S2 and has a low heat resistant component (control chip, etc.) 322 that has a lower heat resistance than the heat generating component (relay, etc.) 321 mounted thereon.

[0077] The electrical connection box 10 is provided with a heat conduction suppression section 80 that is interposed between a heat-generating component (relay, etc.) 321 and a low heat-resistant component (control chip, etc.) 322 and suppresses the transfer of heat generated in the heat-generating component (relay, etc.) 321 to the low heat-resistant component (control chip, etc.) 322.

[0078] Furthermore, in this embodiment, the storage space S2 is partitioned into a first storage space S21 in which a heat-generating component 321 mounted on the first circuit board 311 is present, and a second storage space S22 in which a low heat-resistant component 322 mounted on the second circuit board 312 is present.

[0079] In this embodiment, similarly to the electric junction box 10 shown in FIG. 8, the electric current flowing through the circuit formed on the second circuit board 312 is prevented from flowing through the first circuit board 311. In the embodiment shown in FIG.

[0080] Here, in this embodiment, the case 20 includes a case body 200 and a cover 23 attached to the outside of the case body 200. A first accommodation space S21 is formed inside the case body 200, and a second accommodation space S22 is formed between the case body 200 and the cover 23. In this manner, the case body 200 constitutes at least a part of the heat conduction suppressing unit 80.

[0081] 9 to 11, the case 20 includes an upper case 21 and a lower case 22, and the upper case 21 is assembled to the lower case 22 to form a case body 200 having a first storage space S21 therein. A recess that is recessed downward is formed in the top wall 211 of the upper case 21, and the opening of this recess is closed by the cover 23 to form a second storage space S22.

[0082] In this embodiment, a recess is formed in the top wall 211 of the upper case 21, the recess being defined by a rear wall 2111 and a peripheral wall 2112 that is connected to and extends upward from the peripheral edge of the rear wall 2111. The second circuit board 312 is inserted into this recess and fixed to the rear wall 2111 with screws 70, and the opening of the recess is closed with the cover 23, so that the second circuit board 312 is accommodated in the second accommodation space S22.

[0083] In this embodiment, as shown in Fig. 10 and Fig. 11, an insertion hole 2111a is formed in the back wall 2111 penetrating in the vertical direction. An input side connection pin 512 for supplying a current to a circuit formed on the second circuit board 312 and an output side connection pin 522 for introducing a current from the circuit formed on the second circuit board 312 are inserted into the insertion hole 2111a. If necessary, the pin header 33 is also inserted into the insertion hole 2111a. Fig. 11 illustrates an electric connection box 10 in which the input side connection pin 512, the output side connection pin 522, and the pin header 33 are inserted into the insertion hole 2111a.

[0084] In this manner, in this embodiment, the first circuit board 311 is disposed inside the case body 200 having the function of the thermal conduction suppression unit 80, and the second circuit board 312 is disposed outside the case body 200. In this manner, it is possible to more reliably suppress the low heat-resistant component 322 from being affected by the heat generated by the heat-generating component 321.

[0085] In this embodiment, the first housing space S21 and the second housing space S22 are separated by using the case body 200 in which the first circuit board 311 is housed. This makes it possible to reduce the influence of heat on the low heat resistant component 322 with an easier and simpler configuration.

[0086] Furthermore, in this embodiment, the cover 23 is made of a material with relatively good heat dissipation properties, such as aluminum, and the entire cover 23 functions as a heat dissipation section 91 that efficiently dissipates heat in the second accommodation space S22 to the outside. It is also possible to provide the heat dissipation section 91 in a portion of the cover 23.

[0087] This makes it possible to more reliably prevent heat from building up in the second housing space S22 in which the second circuit board 312 is housed, thereby further reducing the effects of heat on the low heat resistant component 322.

[0088] The electrical junction box 10 may have a configuration as shown in FIG.

[0089] 12, the case 20 includes a case body 200 and a cover 23 attached to the outside of the case body 200. A first accommodation space S21 is formed inside the case body 200, and a second accommodation space S22 is formed between the case body 200 and the cover 23. The case body 200 constitutes at least a part of the heat conduction suppression section 80.

[0090] 12, the first circuit board 311 is disposed inside the case body 200 that functions as the heat conduction suppression section 80, and the second circuit board 312 is disposed outside the case body 200. The case body 200 that houses the first circuit board 311 is used to separate the first housing space S21 and the second housing space S22. Furthermore, the entire cover 23 functions as a heat dissipation section 91 that efficiently dissipates heat in the second housing space S22 to the outside.

[0091] Here, in the electric connection box 10 shown in FIG. 12, a heat conductive portion 92 capable of transmitting heat in the second housing space S22 to the heat dissipation portion 91 is disposed in the second housing space S22. Specifically, in a state in which the first circuit board 311 is fixed to the rear wall 2111 by the screws 70, a potting resin is poured into a recess formed in the top wall 211 and hardened, thereby forming the heat conductive portion 92. In this manner, by pouring the potting resin and hardening it in a state in which the first circuit board 311 is fixed to the case body 200, the mounted components 32 can be covered with resin with less effort than the case in which the resin coating portion 81 is formed in advance as shown in the first embodiment. The heat conductive portion 92 can also be formed using a heat conductive sheet.

[0092] In this manner, by arranging the heat conductive portion 92 in the second storage space S22, the heat within the second storage space S22 can be more reliably discharged to the outside, and the effect of heat on the low heat resistant component 322 can be further reduced.

[0093] The electric junction box 10 may also be configured as shown in FIG.

[0094] 13, the case 20 includes a case body 200 and a cover 23 attached to the outside of the case body 200. A first accommodation space S21 is formed inside the case body 200, and a second accommodation space S22 is formed between the case body 200 and the cover 23. The case body 200 constitutes at least a part of the heat conduction suppression section 80.

[0095] 13, the first circuit board 311 is disposed inside the case body 200 having the function of the heat conduction suppression section 80, and the second circuit board 312 is disposed outside the case body 200. The case body 200 in which the first circuit board 311 is housed is used to separate the first housing space S21 and the second housing space S22. Furthermore, the entire cover 23 functions as a heat dissipation section 91 that efficiently dissipates heat in the second housing space S22 to the outside.

[0096] 13, a control circuit is also formed on first circuit board 311. That is, first circuit board 311 is mounted with not only heat generating components 321 such as relays, but also low heat resistant components 322 such as control chips that have lower heat resistance than heat generating components 321 such as relays.

[0097] In this manner, the first circuit board 311 is formed with a first region R1 in which heat-generating components (relays, etc.) 321 are mainly mounted, and a second region R2 in which low heat-resistant components (control chips, etc.) 322 are mainly mounted.

[0098] Furthermore, the electric junction box 10 shown in FIG. 13 includes a bus bar 34 that divides the current flowing through the first circuit board 311.

[0099] The bus bar 34 is mounted on the circuit board 31 with the thickness direction aligned with the surface 311a of the first circuit board 311, and has a partition wall portion 341 that separates the first region R1 and the second region R2. Note that the electrical junction box 10 shown in FIG. 13 illustrates an example in which the partition wall portion 341 is provided with a connection pin 3411 that is connected to the second circuit board 312.

[0100] 13, a heat generating component (relay, etc.) 321 and a low heat resistant component (control chip, etc.) 322 are mounted on a first circuit board (one circuit board) 311. A first region R1 and a second region R2 are formed on one circuit board 31. The first region R1 and the second region R2 are partitioned by a partition wall portion 341 mounted vertically on the circuit board 31. In this case, the upper end of the partition wall portion 341 may be in contact with the inner surface of the case 20, or a gap may be formed between the upper end of the partition wall portion 341 and the inner surface of the case 20.

[0101] By providing such partition wall portion 341, the transfer of heat generated in heat generating component 321 to low heat resistant component 322 is suppressed by partition wall portion 341 mounted in a vertical position on circuit board 31. That is, thermal interference between heat generating component 321 and low heat resistant component 322 mounted on first circuit board (single circuit board) 311 is suppressed.

[0102] In this way, even if heat-generating component 321 and low heat-resistant component 322 are mounted on first circuit board (single circuit board) 311, it is possible to prevent low heat-resistant component 322 from being affected by the heat generated by heat-generating component 321.

[0103] In this way, by using partition wall portion 341 of busbar 34 to prevent low heat resistant component 322 from being affected by heat generated by heat generating component 321, it becomes possible to arrange components at a high density on first circuit board (single circuit board) 311. As a result, it becomes possible to make the arrangement space for components on first circuit board (single circuit board) 311 more compact, and it becomes possible to reduce the size of circuit board 31.

[0104] Furthermore, if bus bar 34 has partition wall portion 341 mounted vertically on first circuit board 311, heat can be released from partition wall portion 341, thereby reducing the amount of heat transferred to first circuit board 311. As a result, it is possible to keep the temperature rise of first circuit board 311 low when a large current flows through first circuit board 311.

[0105] Furthermore, in the electric connection box 10 shown in FIG. 13, the second region R2 is formed in only one place on the first circuit board 311. That is, the areas where low heat-resistant components 322 such as a control chip are mainly mounted are concentrated in one place. This makes it easier to design the first circuit board 311 (e.g., measures against noise, etc.), and also simplifies the shape of the bus bar 34. In addition, it is possible to prevent dead space from being formed on the first circuit board 311, so that components can be arranged on the first circuit board (one circuit board) 311 with higher density. The second region R2 may be formed in multiple places on the first circuit board (one circuit board) 311.

[0106] Furthermore, in the electrical junction box 10 shown in FIG. 13, a partition wall portion 341 is disposed so as to surround the periphery of the second region R2.

[0107] This makes it possible to further improve the shielding effect of the second region R2 by the surrounding partition wall 341. By further improving the shielding effect of the second region R2 in this way, it becomes possible to more reliably prevent noise from being generated in electronic components arranged in the second region R2 due to, for example, a coil magnetic field generated by a relay.

[0108] Furthermore, if the bus bar 34 is arranged vertically with respect to the first circuit board 311, the bus bar 34 (partition wall portion 341) can also be arranged in the narrow space between the relays (heat generating components 321). For this reason, in the electrical connection box 10 shown in Fig. 13, the vertically arranged partition wall portion 341 of the bus bar 34 also partitions adjacent relays (heat generating components 321). In this way, the partition wall portion 341 can also function as a heat sink, so that the heat generated by the relays (heat generating components 321) can be dissipated more efficiently.

[0109] 13 uses bus bar 34 to suppress thermal interference between heat-generating component 321 and low heat-resistant component 322, suppress a temperature rise in first circuit board 311, dissipate heat from heat-generating component 321, and take measures against noise, etc. In this way, electric junction box 10 in which thermal interference between heat-generating component 321 and low heat-resistant component 322, temperature rise in first circuit board 311, heat dissipation from heat-generating component 321, and measures against noise, etc. are implemented can be obtained at a lower cost.

[0110] It is also possible to configure the heat generating components 321 and the low heat resistant components 322 on the second circuit board (one circuit board) 312. It is also possible to configure the heat generating components 321 and the low heat resistant components 322 on each of the first circuit board 311 and the second circuit board 312. In either configuration, it is preferable that the heat generating components 321 and the low heat resistant components 322 mounted on one circuit board are separated by the partition wall portion 341 of the bus bar 34.

[0111] [Actions and Effects] The characteristic configurations of the electrical junction boxes shown in the above embodiments and their modified examples and the effects obtained thereby will be described below.

[0112] The electric junction box 10 shown in each of the above embodiments and their modified examples includes a case 20 and a first circuit board 311 that is accommodated in the accommodation space S2 in the case 20 and has a heat generating component (relay, etc.) 321 mounted thereon. The electric junction box 10 also includes a second circuit board 312 that is accommodated in the accommodation space S2 and has a low heat resistant component (control chip, etc.) 322 that has a lower heat resistance than the heat generating component (relay, etc.) 321 mounted thereon.

[0113] The electrical connection box 10 is provided with a heat conduction suppression section 80 that is interposed between a heat-generating component (relay, etc.) 321 and a low heat-resistant component (control chip, etc.) 322 and suppresses the transfer of heat generated in the heat-generating component (relay, etc.) 321 to the low heat-resistant component (control chip, etc.) 322.

[0114] In this way, in the electrical connection box 10 shown in each of the above embodiments and their modified examples, the transfer of heat generated in the heat-generating component 321 to the low heat-resistant component 322 is suppressed by the heat conduction suppression section 80 interposed between the heat-generating component 321 and the low heat-resistant component 322.

[0115] This prevents the heat generated in the heat generating component 321 from being transferred to the low heat resistant component 322. That is, this prevents thermal interference between the heat generating component 321 and the low heat resistant component 322. As a result, this prevents the low heat resistant component 322 from being affected by the heat generated in the heat generating component 321.

[0116] In this way, by using the electrical connection box 10 shown in each of the above embodiments and their modified examples, it is possible to more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat-generating component 321.

[0117] Furthermore, if the thermal interference between the heat-generating component 321 and the low heat-resistant component 322 is suppressed by the heat conduction suppression section 80, it becomes possible to mount many components on the circuit board and pass a larger current than before, without changing the size of the electrical junction box 10. In other words, even if a higher-density circuit board (circuit block 30) is mounted while keeping the size of the electrical junction box 10 the same or smaller than before, it becomes possible to keep the temperature rise of the electrical junction box 10 low.

[0118] In addition, the storage space S2 may be divided by the heat conduction suppression section 80 into a first storage space S21 in which a heat-generating component 321 mounted on the first circuit board 311 is present, and a second storage space S22 in which a low heat-resistant component 322 mounted on the second circuit board 312 is present.

[0119] In this way, the first accommodation space S21, which accommodates the first circuit board 311 on which the heat-generating components 321 are mainly mounted, and the second accommodation space S22, which accommodates the second circuit board 312 on which the low heat-resistant components 322 are mainly mounted, are separated by the heat conduction suppression section 80. Therefore, the transfer of heat between the first accommodation space S21 and the second accommodation space S22 is suppressed by the heat conduction suppression section 80.

[0120] In this way, by being able to suppress the transfer of heat from the space housing first circuit board 311 to the space housing second circuit board 312, it becomes possible to more reliably suppress the low heat resistant component 322 from being affected by the heat generated by heat-generating component 321.

[0121] Moreover, the case 20 may include a case body 200 and a cover 23 attached to the outside of the case body 200. Moreover, a first accommodation space S21 may be formed inside the case body 200, and a second accommodation space S22 may be formed between the case body 200 and the cover 23. The case body 200 may constitute at least a part of the heat conduction suppression unit 80.

[0122] In this way, by using the case body 200 in which the first circuit board 311 is housed to separate the first storage space S21 and the second storage space S22, it is possible to reduce the effects of heat on the low heat resistant component 322 with an easier and simpler configuration.

[0123] Additionally, the cover 23 may have a heat dissipation portion 91 .

[0124] This prevents heat from building up in the second storage space S22 which houses the second circuit board 312 on which the low heat resistant components 322 are mounted, thereby making it possible to further reduce the effects of heat on the low heat resistant components 322.

[0125] Further, in the second accommodation space S22, a heat conduction section 92 that transfers heat in the second accommodation space S22 to the heat dissipation section 91 may be disposed.

[0126] This makes it possible to more reliably exhaust the heat within the second accommodation space S22 to the outside, so that the influence of heat on the low heat-resistant component 322 can be further reduced.

[0127] In addition, the electrical connection box 10 may further include a resin coating portion 81 that covers the low heat resistant component 322 mounted on the second circuit board 312, and this resin coating portion 81 may constitute at least a part of the thermal conduction suppression portion 80.

[0128] In this way, simply by forming the resin coating portion 81, it is possible to more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat generating component 321. Therefore, it is not necessary to separately provide the cover 23 or to change the shape of the case body 200 (case 20). As a result, it is possible to more easily and at low cost obtain the electric junction box 10 that can more reliably prevent the low heat resistant component 322 from being affected by the heat generated by the heat generating component 321.

[0129] [others] Although the present embodiment has been described above, the present embodiment is not limited to this, and various modifications are possible within the scope of the gist of the present embodiment.

[0130] For example, the configurations shown in the above embodiments and their modified examples can be combined as appropriate.

[0131] Furthermore, in each of the above embodiments and their modifications, the electrical junction box 10 to which the body ECU 120 is attached has been exemplified, but the present invention can also be applied to a simple electrical junction box to which the body ECU 120 is not attached.

[0132] In addition, the case, fuse block, and other detailed specifications (shape, size, layout, etc.) can be changed as appropriate. [Explanation of symbols]

[0133] 10 Electrical junction box 20 cases 200 Case body 311 First Circuit Board 312 Second Circuit Board 321 Heat generating parts 322 Low heat resistant parts 80 Heat conduction suppression section 81 Resin-coated part 91 Heat radiation part 92 Heat Conduction Section S2 Containment Space S21 First Storage Space S22 Second Storage Space

Claims

1. Case and a first circuit board that is accommodated in the accommodation space within the case and on which a heat generating component is mounted; a second circuit board that is accommodated in the accommodation space and has a low heat resistant component that has a lower heat resistance than the heat generating component mounted thereon; a heat conduction suppressing portion interposed between the heat generating component and the low heat resistant component and configured to suppress the conduction of heat generated by the heat generating component to the low heat resistant component; Equipped with Electrical junction box.

2. the accommodation space is partitioned by the heat conduction suppression portion into a first accommodation space in which the heat-generating component mounted on the first circuit board is present and a second accommodation space in which the low heat-resistant component mounted on the second circuit board is present.

2. The electrical junction box according to claim 1.

3. The case includes a case body and a cover attached to an exterior of the case body, The first storage space is formed in the case body, The second accommodation space is formed between the case body and the cover, The case body constitutes at least a part of the heat conduction suppressing portion.

3. The electrical junction box according to claim 2.

4. The cover has a heat dissipation portion.

4. The electrical junction box according to claim 3.

5. A heat conductive portion that transfers heat in the second accommodation space to the heat dissipation portion is disposed in the second accommodation space.

5. The electrical junction box according to claim 4.

6. a resin coating portion that coats the low heat resistant component mounted on the second circuit board; The resin coating portion constitutes at least a part of the heat conduction suppressing portion. The electrical junction box according to any one of claims 1 to 5.

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