Electric connection box

The electrical connection box uses a bus bar with a partition wall to separate heat-generating and low heat-resistant components, addressing thermal interference and space constraints, ensuring reliable operation and compactness.

JP2025005737APending Publication Date: 2025-01-17YAZAKI CORP
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Patent Information

Application Number
JP2023106048
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2023-06-28
Publication Date
2025-01-17

AI Technical Summary

Technical Problem

Conventional electrical connection boxes face issues where low heat-resistant components, such as microcomputers, are affected by heat generated from high heat-generating components like relays due to their close proximity on a circuit board, leading to potential damage and space constraints in vehicles.

Method used

The electrical connection box incorporates a bus bar with a partition wall that separates heat-generating components (like relays) and low heat-resistant components (like control chips) on the circuit board, preventing thermal interference and allowing for compact arrangement by directing heat away from sensitive components.

Benefits of technology

This design effectively prevents low heat-resistant components from being affected by heat, allows for higher component density, reduces temperature rise, and enhances noise shielding, all while maintaining a compact design at a lower cost.

✦ Generated by Eureka AI based on patent content.

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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 circuit board 31 that is housed in a housing space S2 in the case 20. The electric connection box 10 has a heat-generating component 321 mounted on the circuit board 31, a low heat-resistant component 322 mounted on the circuit board 31 and having lower heat resistance than the heat-generating component 321, and a bus bar 34 that diverts current to the circuit board 31. Here, the circuit board 31 has a first region R1 where the heat-generating components 321 are mainly mounted and a second region R2 where the low heat-resistant components 322 are mainly mounted. The bus bar 34 is mounted on the circuit board 31 with its thickness direction along the surface 31a of the circuit board 31, and has a partition wall 341 that divides the first region R1 and the second region R2.SELECTED DRAWING: Figure 7
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Description

[Technical field]

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

[0002] A conventional electrical junction box of this type is disclosed in Patent Document 1. Patent Document 1 discloses an electrical junction box equipped with a circuit board. On this circuit board, a load circuit section including a relay, a driving IC, and a conductor pattern, and a control circuit section including a microcomputer, a connector section, and a conductor pattern are formed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-267596 A Summary of the Invention [Problem to be solved by the invention]

[0004] 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.

[0005] 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.

[0006] 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.

[0007] 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.

[0008] 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]

[0009] An electrical junction box according to one embodiment of the present invention comprises a case, a circuit board accommodated in an accommodation space within the case, a heat-generating component mounted on the circuit board, a low heat-resistant component mounted on the circuit board and having a lower heat resistance than the heat-generating component, and a bus bar that shunts current flowing through the circuit board, wherein the circuit board is formed with a first region in which the heat-generating component is mainly mounted and a second region in which the low heat-resistant component is mainly mounted, and the bus bar is mounted on the circuit board with its thickness direction aligned with the surface of the circuit board and has a partition wall portion that separates the first region from the second region. Effect of the Invention

[0010] 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]

[0011] [Figure 1] 1 is a perspective view showing a schematic example of a method of arranging an ECU-equipped electrical junction box according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing a schematic diagram of an ECU-equipped electrical junction box according to an embodiment of the present invention; [Diagram 3] FIG. 2 is an exploded perspective view showing a schematic diagram of an ECU-equipped electrical junction box according to one embodiment; [Figure 4] FIG. 2 is a perspective view showing an example of an electrical junction box according to an embodiment, in which the electrical junction box is seen in an assembled state from one direction. [Diagram 5]FIG. 13 is a perspective view showing an example of an electrical junction box according to an embodiment, with a fuse cover open, as viewed from another direction. [Figure 6] FIG. 2 is an exploded perspective view showing an example of an electrical junction box according to an embodiment, as viewed from one direction. FIG. [Figure 7] 2 is a perspective view of an example of a circuit block included in an electrical junction box according to an embodiment, seen from one direction. FIG. [Figure 8] FIG. 13 is an exploded perspective view showing another example of the electrical junction box according to the embodiment, as viewed from one direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] Therefore, there is a demand for making it possible to arrange more devices (electrical junction boxes 10 and ECUs 110) in a limited space.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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).

[0023] 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.

[0024] 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.

[0025] Next, a specific configuration of the electrical junction box 10 according to this embodiment will be described with reference to FIGS.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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. Furthermore, the circuit block 30 includes a bus bar 34 that divides the current flowing through the circuit board 31.

[0039] In this embodiment, the circuit block 30 has a circuit for current distribution and a circuit for control. The circuit for current distribution and the circuit for control are formed on one circuit board 31.

[0040] 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.

[0041] 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.

[0042] Therefore, one circuit board 31 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.

[0043] The body ECU connector 40 includes a housing 41 and a plurality of connection pins 42 held by the housing 41. The housing 41 is fixed to the circuit board 31 by screws 70. The plurality of connection pins 42 are electrically connected to the circuit of the circuit board 31. In this manner, the body ECU connector 40 is held in a state in which it is electrically connected to the circuit board 31. The plurality of connection pins 42 are fixed to the circuit board 31 by using solder or the like.

[0044] 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.

[0045] The input wire harness connector 51 and the output wire harness connector 52 are each held by the circuit board 31 .

[0046] 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 circuit board 31 by screws 70. Furthermore, the plurality of input side connection pins 512 are electrically connected to the circuit of the circuit board 31. In this manner, the input side wire harness connector 51 is held in a state in which it is electrically connected to the circuit board 31. The plurality of input side connection pins 512 are also fixed to the circuit board 31 by using solder or the like.

[0047] 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 circuit board 31 by screws 70. Furthermore, the plurality of output-side connection pins 522 are electrically connected to the circuit of the circuit board 31. In this manner, the output-side wire harness connector 52 is held in a state in which it is electrically connected to the circuit board 31. The plurality of output-side connection pins 522 are also fixed to the circuit board 31 by using solder or the like.

[0048] 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.

[0049] The housing 61 is fixed to the circuit board 31 by screws 70. Furthermore, the connection pins 62 are electrically connected to the circuit of the circuit board 31. In this manner, the fuse block 60 is held in a state of being electrically connected to the circuit board 31, and a circuit with a fuse function is formed on the circuit board 31. The multiple connection pins 62 are also fixed to the circuit board 31 by soldering or the like.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] Here, in this embodiment, thermal interference between the heat generating component 321 and the low heat resistant component 322 mounted on one circuit board 31 can be more reliably prevented.

[0055] Specifically, the electric junction box 10 is provided with a bus bar 34 that divides the current flowing through the circuit board 31 .

[0056] This bus bar 34 is mounted on the circuit board 31 with its thickness direction aligned with the surface 31a of the circuit board 31, so as to have a partition wall portion 341 that separates the first region R1 and the second region R2.

[0057] In this manner, in this embodiment, heat generating components (relays, etc.) 321 and low heat resistant components (control chips, etc.) 322 are mounted on one circuit board 31. 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. At this time, 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.

[0058] By providing such a partition wall portion 341, the transfer of heat generated in the heat-generating component 321 to the low heat-resistant component 322 is suppressed by the partition wall portion 341 mounted in a vertical position on the circuit board 31. In other words, thermal interference between the heat-generating component 321 and the low heat-resistant component 322 mounted on one circuit board 31 is suppressed.

[0059] In this way, even if a heat-generating component 321 and a low heat-resistant component 322 are mounted on a single circuit board 31, it is possible to prevent the low heat-resistant component 322 from being affected by the heat generated by the heat-generating component 321.

[0060] In this way, by using partition wall portion 341 of bus bar 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 one circuit board 31. As a result, it becomes possible to make the arrangement space for components on one circuit board 31 more compact, and it becomes possible to reduce the size of circuit board 31.

[0061] Furthermore, if bus bar 34 has partition wall portion 341 mounted vertically on circuit board 31, heat can be released from partition wall portion 341, thereby reducing the amount of heat transferred to circuit board 31. As a result, it is possible to keep the temperature rise of circuit board 31 low when a large current flows through circuit board 31.

[0062] Furthermore, in this embodiment, the second region R2 is formed in only one place on the circuit board 31. That is, the regions 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 circuit board 31 (e.g., measures against noise, etc.), and also makes it possible to simplify the shape of the bus bar 34. In addition, it becomes possible to prevent dead space from being formed on the circuit board 31, so that components can be arranged on one circuit board 31 with higher density. The second region R2 may be formed in multiple places on one circuit board 31.

[0063] Furthermore, in this embodiment, a partition wall portion 341 is disposed so as to surround the periphery of the second region R2.

[0064] 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.

[0065] Furthermore, if the bus bar 34 is arranged vertically on the circuit board 31, 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 this embodiment, 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 in the relays (heat generating components 321) can be dissipated more efficiently.

[0066] As described above, in this embodiment, the bus bar 34 is used to suppress thermal interference between the heat-generating component 321 and the low heat-resistant component 322, suppress a temperature rise in the circuit board 31, dissipate heat from the heat-generating component 321, and take measures against noise, etc. In this way, it is possible to obtain, at a lower cost, the electric junction box 10 in which the thermal interference between the heat-generating component 321 and the low heat-resistant component 322, the temperature rise in the circuit board 31, the heat dissipation of the heat-generating component 321, and measures against noise are implemented.

[0067] The electric junction box 10 may have a configuration as shown in FIG.

[0068] The electrical junction box 10 shown in Fig. 8 also includes a case 20 and a circuit board 31 accommodated in an accommodation space S2 inside the case 20. The electrical junction box 10 shown in Fig. 8 also includes a heat-generating component (relay, etc.) 321 mounted on the circuit board 31, and a low heat-resistant component (control chip, etc.) 322 mounted on the circuit board 31 and having lower heat resistance than the heat-generating component (relay, etc.) 321. The electrical junction box 10 shown in Fig. 8 also includes a bus bar 34 that shunts the current flowing through the circuit board 31.

[0069] 8, 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. 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.

[0070] That is, heat generating components 321 such as relays used in a current distribution circuit are mainly mounted on the first circuit board 311, and low heat resistant components 322 such as control chips used in a control circuit are mainly mounted on the second circuit board 312. In this manner, thermal interference between heat generating components 321 mounted on the first circuit board 311 and low heat resistant components 322 mounted on the second circuit board 312 is suppressed.

[0071] 8, a control circuit is also formed on the first circuit board 311. That is, 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 are mounted on the first circuit board 311. Therefore, in the electric junction box 10 shown in FIG. 8, the first circuit board 311 corresponds to one circuit board 31 shown in the first embodiment.

[0072] In addition, in the electrical connection box 10 shown in FIG. 8, the circuit block 30 is provided with a pin header 33, which holds the second circuit board 312 at a predetermined distance from the first circuit board 311.

[0073] 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.

[0074] 8, the current supplied to input side connection pin 512 is supplied to the circuit formed on second circuit board 312 through the 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, the circuit formed on first circuit board 311, and output side connection pin 522.

[0075] It is also possible to allow a current to flow through a circuit formed on second circuit board 312 without passing through first circuit board 311.

[0076] Specifically, 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 a circuit formed on the second circuit board 312 is directly fixed to the second circuit board 312. And, 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 directly fixed to the second circuit board 312.

[0077] This makes it possible to prevent the current flowing through the circuit formed on second circuit board 312 from flowing through first circuit board 311, thereby suppressing the generation of heat in first circuit board 311 due to the current flowing through the circuit formed on second circuit board 312. As a result, it becomes possible to suppress the temperature of first circuit board 311 from increasing.

[0078] 8, 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. 8 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.

[0079] 8, 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] Furthermore, in the electric connection box 10 shown in FIG. 8, 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.

[0085] Furthermore, in the electrical junction box 10 shown in FIG. 8, a partition wall portion 341 is disposed so as to surround the periphery of the second region R2.

[0086] 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.

[0087] 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 junction box 10 shown in Fig. 8, 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.

[0088] 8 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.

[0089] 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.

[0090] [Actions and Effects] The characteristic configurations of the electrical junction boxes shown in the above embodiment and the modified examples thereof and the effects obtained thereby will be described below.

[0091] The electrical junction box 10 shown in the above embodiment and its modified examples includes a case 20 and a circuit board 31 accommodated in an accommodation space S2 inside the case 20. The electrical junction box 10 also includes a heat-generating component (relay, etc.) 321 mounted on the circuit board 31, and a low heat-resistant component (control chip, etc.) 322 mounted on the circuit board 31 and having lower heat resistance than the heat-generating component (relay, etc.) 321. The electrical junction box 10 also includes a bus bar 34 that shunts the current flowing through the circuit board 31.

[0092] Here, the circuit board 31 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.

[0093] Bus bar 34 is mounted on circuit board 31 with its thickness direction aligned with surface 31a of circuit board 31, and has a partition wall portion 341 that separates first region R1 and second region R2.

[0094] In this manner, in the electric connection box 10 shown in the above embodiment and its modified example, a heat generating component (relay, etc.) 321 and a low heat resistant component (control chip, etc.) 322 are mounted on one circuit board 31. 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 separated by a partition wall portion 341 mounted on the circuit board 31 in a vertically oriented state.

[0095] In this way, the transfer of heat generated in the heat generating component 321 to the low heat resistant component 322 is suppressed by the partition wall 341 mounted in an upright position on the circuit board 31. That is, thermal interference between the heat generating component 321 and the low heat resistant component 322 is suppressed. As a result, the low heat resistant component 322 is prevented from being affected by the heat generated by the heat generating component 321.

[0096] In this way, with the electrical junction box 10 shown in the above embodiment and its modified example, 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.

[0097] Furthermore, by using partition wall portion 341 of bus bar 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 one circuit board 31. In this way, it becomes possible to make the arrangement space for components on one circuit board 31 more compact, and it becomes possible to reduce the size of circuit board 31.

[0098] Furthermore, if bus bar 34 has partition wall portion 341 mounted vertically on circuit board 31, heat can be released from partition wall portion 341, thereby reducing the amount of heat transferred to circuit board 31. As a result, it is possible to keep the temperature rise of circuit board 31 low when a large current flows through circuit board 31.

[0099] Moreover, the second region R2 may be formed in only one place on the circuit board 31.

[0100] In this way, by gathering the areas where low heat resistant components (control chips, etc.) 322 are mainly mounted in one place, it becomes easier to design the circuit board 31 (for example, measures against noise, etc.), and it becomes possible to simplify the shape of the bus bar 34. In addition, it becomes possible to prevent dead space from being formed on the circuit board 31, so that it becomes possible to arrange components on one circuit board 31 with higher density.

[0101] Moreover, a partition wall portion 341 may be disposed so as to surround the periphery of the second region R2.

[0102] In this way, the shielding effect of the second region R2 is improved by the surrounding partition wall portion 341, so that it is possible to more reliably prevent noise from being generated in electronic components placed in the second region R2 due to, for example, a coil magnetic field generated by a relay.

[0103] In this way, in the above embodiment and its modified examples, the bus bar 34 is used to suppress thermal interference between the heat-generating component 321 and the low heat-resistant component 322, suppress a temperature rise in the circuit board 31, dissipate heat from the heat-generating component 321, and take measures against noise, etc. In this way, it is possible to obtain, at a lower cost, the electrical junction box 10 in which thermal interference between the heat-generating component 321 and the low heat-resistant component 322, temperature rise in the circuit board 31, heat dissipation from the heat-generating component 321, and measures against noise are implemented.

[0104] [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.

[0105] For example, the configurations shown in the above-described embodiments and their modifications can be combined as appropriate.

[0106] Furthermore, in the above embodiment and its modified example, 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.

[0107] In addition, the case, fuse block, and other detailed specifications (shape, size, layout, etc.) can be changed as appropriate. [Explanation of symbols]

[0108] 10 Electrical junction box 20 cases 200 Case body 31 Circuit Board 31a surface 321 Heat generating parts 322 Low heat resistant parts 34 Busbar 341 Partition wall R1 First Region R2 Second Region S2 Containment Space

Claims

1. Case and a circuit board accommodated in an accommodation space within the case; a heat generating component mounted on the circuit board; a low heat resistant component mounted on the circuit board and having a lower heat resistance than the heat generating component; A bus bar that divides a current flowing through the circuit board; Equipped with the circuit board is formed with a first region in which the heat generating components are mainly mounted and a second region in which the low heat resistant components are mainly mounted, the bus bar is mounted on the circuit board with a plate thickness direction aligned along a surface of the circuit board, and has a partition wall portion that separates the first region and the second region. Electrical junction box.

2. The second region is formed in only one place on the circuit board.

2. The electrical junction box according to claim 1.

3. The partition wall portion is disposed so as to surround the periphery of the second region.

3. The electrical junction box according to claim 1 or 2.

Citation Information

Patent Citations

  • Electrical connection box

    JP2007267596A