JP4560460B2 - Electrical junction box - Google Patents

Description

  The present invention relates to an electrical junction box that houses an electronic unit that performs electrical control of a vehicle.

  In general, automobiles as moving bodies are equipped with a wide variety of electronic devices such as lamps such as head lamps and tail lamps, and motors such as motors for starter motors and air conditioners.

  In order to supply electric power to the various electronic devices described above, the automobile has arranged junction blocks at appropriate locations. The junction block is composed of various electric circuit units such as a large number of fuses and relays.

  Note that the junction block may include a fuse, a relay, a bus bar, and the like, and thus is also referred to as a fuse block, a relay box, or an electrical connection box. In the present specification, the above-described fuse block, relay box, and junction block are collectively referred to as an electric junction box (for example, refer to Patent Document 1).

  An electric connection box disclosed in Patent Document 1 includes a storage box that forms an outer shell, an ECU (Electronic Control Unit) as an electronic unit that is stored in the storage box, and a lower cover that is attached to the storage box. And.

  The storage box is formed in a cylindrical shape along the aforementioned outer shape of the ECU, and is provided with a mounting portion for fixing the ECU by storing the ECU. When the lower cover is attached to the storage box described above, the lower cover covers the ECU from the outside of the attachment portion. In addition, an outside air circulation path through which outside air flows is formed in the lower cover.

In the electrical junction box described in Patent Document 1 described above, outside air flows in the lower cover so that the outside air takes heat from the inside of the lower cover, that is, the ECU. Thus, the electric junction box shown in Patent Document 1 described above has cooled the ECU by flowing outside air into the lower cover.
JP 2001-203476 A

  However, since the above-described conventional electrical junction box accommodates only one ECU, it is difficult to cool the ECU when a plurality of ECUs are accommodated.

  Accordingly, an object of the present invention is to provide an electrical junction box that can reliably cool a plurality of electronic units.

In order to solve the above problems and achieve the object, an electrical junction box according to the present invention according to claim 1 includes a plurality of electronic units, a storage box having a plurality of attachment portions to which the electronic units are attached, a cover member attached to the housing box, in the electrical junction box wherein the attachment portion, respectively, comprise at least a portion parallel to and closely wall intimate contact with at least a portion of the outer surface of the outer surface of the electronic unit When the cover member is attached to the storage box, the cover member includes a relative wall provided at a distance from the close wall, and a ventilation path through which gas passes between the relative wall and the close wall. formed, and the relative wall is provided in a manner in spaced closely walls and spacing of all of the mounting portion, at least one of the closely walls close contact with at least a portion of the outer surface of the electronic unit Closely walls of, is characterized in that intimate contact with one surface entire flat of the outer surface of the electronic unit.

  According to a second aspect of the present invention, there is provided the electric junction box according to the first aspect, wherein the close wall is provided with a hole opened in the cover member.

  According to the electrical junction box of the present invention as set forth in claim 1, since the relative wall of the cover member is disposed at a distance from the close wall of all the mounting portions, the gas in the cover member is separated from the relative wall. It will flow between the close walls of all mounting parts.

  According to the electrical junction box of the present invention as set forth in claim 2, since the hole opened in the cover member is provided in the close wall, the electronic unit directly contacts the gas in the cover member through the hole.

  As described above, according to the first aspect of the present invention, since the gas in the cover member flows between the relative wall and the close wall of all the mounting portions, the gas in the cover member is completely attached. Take the heat of the electronic unit through the close wall of the part. Therefore, the electronic unit attached to all the attachment parts can be cooled.

  According to the second aspect of the present invention, since the electronic unit directly contacts the gas in the cover member through the hole, the gas in the cover member can directly cool the electronic unit.

  Hereinafter, an electrical junction box according to an embodiment of the present invention will be described with reference to FIGS. The electrical junction box 1 shown in FIG. 1 according to the present embodiment is mounted on an automobile as a moving body. As shown in FIGS. 1 to 3, the electrical connection box 1 includes a storage box 2, ECUs (Electronic Control Units) 3a and 3b as electronic units stored in the storage box 2, and a lower case 20 (see FIG. 1 only).

  The storage box 2 includes a lower cover 4 that is detachable from each other and an upper cover (not shown). Each of the lower cover 4 and the upper cover is made of an insulating synthetic resin, and is formed by a well-known injection molding. As shown in FIG. 1, the lower cover 4 includes a bottom wall 5 and a plurality of peripheral walls 6 erected from the outer edge of the bottom wall 5 and is formed in a box shape. The lower cover 4 is provided with an exhaust cylinder 21 that guides the gas in the lower case 20 to the outside. The exhaust cylinder 21 opens in the bottom wall 5 of the lower cover 4. The upper cover is formed in a box shape by a plurality of outer walls.

  When the lower cover 4 and the upper cover are attached to each other, they keep watertight between each other. That is, when the lower cover 4 and the upper cover are attached to each other, the storage box 2 prevents liquid such as external water from entering inside. Further, a connector attached to the end of the wire harness or the like is led from the outside into the inner box 2 of the lower cover 4 and the upper cover. The lower cover 4 is provided with a notch 7 through which the end of the wire harness described above is passed.

  In the illustrated example, a pair of ECUs 3a and 3b are provided. As shown in FIGS. 1 to 3, the ECUs 3 a and 3 b include a case 8 and a printed wiring board accommodated in the case 8. The case 8 is provided with a connector. The terminal of the connector is electrically connected to the wiring pattern of the printed wiring board. An electronic component such as a well-known CPU as a heating element is mounted on the printed wiring board. In the ECUs 3a and 3b, the connector of the wire harness that has entered the housing box 2 is fitted into the connector. ECU3a, 3b electrically connects the electric wire of a wire harness, and the electronic component mentioned above according to the predetermined pattern.

  Further, when the ECUs 3a and 3b are attached to the attachment portions 9a and 9b, a part of the case 8 is exposed outside the storage box 2 through holes 22a and 22b described later. This exposed portion is a waterproof portion that restricts the ingress of liquid from the outside without any joints or holes into the case 8.

  The lower cover 4 described above further includes a pair of attachment portions 9a and 9b. As shown in FIG. 1, the one attachment portion 9 a includes a bottom plate portion 10 having a rectangular planar shape and a square tube portion 11 erected from the outer edge of the bottom plate portion 10. The rectangular tube portion 11 passes through the bottom wall 5 of the lower cover 4. The bottom plate portion 10 closes an end portion of the rectangular tube portion 11 that is located outside the lower cover 4.

  For this reason, one attachment part 9a does not connect the inner side and the outer side of the lower cover 4. One mounting portion 9a is inserted by sliding the ECU 3a along its longitudinal direction. One attachment part 9a attaches this ECU3a by accommodating ECU3a. Thus, one attachment part 9a is formed in the cylinder shape, and slides ECU3a and attaches this ECU3a. As shown in FIG. 4, a close wall 11a that is in close contact with the ECU 3a attached to the attachment portion 9a is provided on the outer wall of the square tube portion 11 of one attachment portion 9a. The close wall 11a is parallel to a part of the outer surface of the case 8 of the ECU 3a and is in close contact with a part of the outer surface. One close wall 11b is provided with a hole 22a that communicates the inside and outside of the mounting portion 9a. For this reason, the hole 22 a opens into the lower case 20.

As shown in FIG. 1, the other attachment portion 9 b includes a cylindrical portion 12 erected from the bottom wall 5 toward the upper cover, and a ceiling plate portion 13 that closes an end portion of the cylindrical portion 12 near the upper cover. Are formed into a bottomed cylindrical shape. The cylindrical portion 12 communicates with the lower cover 4, that is, the outside of the electrical junction box 1. That is, the cylindrical portion 12 penetrates the lower cover 4. Further, since the ceiling plate portion 13 closes the end portion of the cylindrical portion 12 near the upper cover, the other attachment portion 9 b does not communicate the inner side and the outer side of the lower cover 4. The other attachment portion 9b attaches the ECU 3b by overlapping the ECU 3b on the surface of the ceiling plate portion 13 near the upper cover. For this reason, as shown in FIG. 5, the ceiling board part 13 is parallel to a part of the outer surface of the case 8 of the ECU 3b attached to the attaching part 9b, and is in close contact with a part of the outer surface. The ceiling board portion 13 forms a close wall. Further, the ceiling plate portion 13 is provided with a hole 22b that communicates the inside and outside of the attachment portion 9a. For this reason, the hole 22 b opens into the lower case 20.

  The lower case 20 is made of a synthetic resin. The lower case 20 is attached to the lower cover of the storage box 2. As shown in FIG. 1, the lower case 20 includes a first ventilation portion 23 formed along the outer shape of the attachment portion 9a, a second ventilation portion 24 formed along the outer shape of the attachment portion 9b, and a ventilation cylinder 25. And integrated. The lower case 20 is attached to the lower cover 4, the first ventilation part 23 covers the attachment part 9a, and the second ventilation part 24 enters the attachment part 9b.

  When the lower case 20 is attached to the lower cover 4, the outer wall constituting the first ventilation portion 23 faces the rectangular tube portion 11 and the bottom plate portion 10 of the attachment portion 9 a with a gap therebetween. For this reason, as shown in FIG. 4, the 1st ventilation part 23 is provided with the relative wall 23a which opposes the close contact wall 11a mentioned above at intervals. The relative wall 23a is parallel to the close wall 11a.

  When the lower case 20 is attached to the lower cover 4, the outer wall constituting the second ventilation portion 24 faces the cylindrical portion 12 and the ceiling plate portion 13 of the attachment portion 9 b with a space therebetween. For this reason, as shown in FIG. 5, the second ventilation portion 24 is provided with a relative wall 24 a that is opposed to the ceiling plate portion 13 as a close wall described above with a space therebetween. The relative wall 24a is parallel to the ceiling plate portion 13 as a close wall.

  In this way, the relative walls 23a and 24a of the lower case 20 are arranged at intervals from the close contact walls 11a and 13 of all the attachment portions 9a and 9b. In addition, since the relative walls 23a and 24a are spaced apart from the close walls 11a and 13, the lower case 20 has a ventilation path R () through which gas passes between the relative walls 23a and 24a and the close walls 11a and 13. 1, 4, and 5).

  The ventilation tube 25 is formed in a rectangular tube shape, and extends linearly along the sliding direction of the ECU 3a with respect to the mounting portion 9a. The ventilation tube 25 has one end opened to the outside of the electrical junction box 1 and the other end opened to a relative wall 24 a facing the ceiling plate part 13 with a gap. That is, the ventilation tube 25 is open to a space between the lower case 20 and the lower cover 4. The ventilating tube 25 having the above-described structure guides the gas outside the electrical junction box 1 between the lower case 20 and the lower cover 4 described above.

  External gas is introduced into the lower case 20, that is, between the lower case 20 and the lower cover 4 through the ventilation tube 21. Further, the gas in the lower case 20, that is, between the lower case 20 and the lower cover 4 is discharged to the outside through the exhaust pipe 24. In the lower case 20, the gas outside the storage box 2 flows from the ventilation tube 21 toward the exhaust hole 24.

  The gas in the lower case 20 from the ventilation tube 21, that is, between the lower case 20 and the lower cover 4, first branches into a first ventilation portion 23 and a second ventilation portion 24 as shown by an arrow K 1 in FIG. While flowing between the wall 23a and the close wall 11a, it flows between the relative wall 24a and the ceiling plate part 13 as the close wall. Then, as shown by an arrow K2 in FIG. 7, the gas between the lower case 20 and the lower cover 4 merges again and is discharged to the outside of the electrical junction box 1 through the exhaust tube 21.

  According to the present embodiment, since the relative walls 23a, 24a of the lower case 20 are arranged at intervals from the close-contact walls 11a, 13 of all the attachment portions 9a, 9b, the gas in the lower case 20 is relative to the relative wall 23a. , 24a and the close walls 11a, 13 of all the attachment portions 9a, 9b. Thereby, the gas in the lower case 20 takes the heat of all the ECUs 3a and 3b through the close walls 11a and 13 of all the attachment portions 9a and 9b. Therefore, ECU3a, 3b attached to all the attaching parts 9a, 9b can be cooled.

  Since the close-contact walls 11a and 13 are provided with holes 22a and 23a opened in the lower case 20, the ECUs 3a and 3b are in direct contact with the gas in the lower case 20 through the holes 22a and 23a. The ECUs 3a and 3b can be directly cooled.

  In the above-described embodiment, the ECUs 3a and 3b are shown as electronic units. In the present invention, not only the ECUs 3a and 3b, but other electronic devices such as so-called fuse blocks and junction blocks may be used as electronic units.

  In the above-described embodiment, there is no description of installing a fan, a blower, or the like in the vicinity of the exhaust tube 21 and the ventilation tube 25. However, in the present invention, of course, in order to improve the cooling efficiency of the ECUs 3a and 3b, a fan, a blower, or the like may be installed in the vicinity of the exhaust tube 21 and the ventilation tube 25. Furthermore, in the present invention, an external gas is provided between the lower case 20 and the lower cover 4 through the ventilation cylinder 25 by a natural gas flow without installing a fan or a blower in the vicinity of the exhaust cylinder 21 and the ventilation cylinder 25. You may lead.

  In the above-described embodiment, the close walls 11a and 13 are provided in parallel with part of the outer surface of the case 8 of the ECUs 3a and 3b. However, in the present invention, a close wall parallel to the entire outer surface of the case 8 of the ECUs 3a and 3b may be provided.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

It is a perspective view which shows the principal part of the electrical-connection box concerning one Embodiment of this invention in a cross section. FIG. 2 is a plan view of the electric junction box shown in FIG. 1. It is a perspective view which shows the storage box, ECU, etc. of the electrical junction box shown by FIG. It is sectional drawing which follows the IV-IV line in FIG. It is sectional drawing which follows the VV line in FIG. It is explanatory drawing explaining the state which the gas guide | induced from the ventilation cylinder of the electrical-connection box shown by FIG. 1 branches. It is explanatory drawing explaining the state which the gas shown by FIG. 6 merges again.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrical junction box 2 Storage box 3a, 3b ECU (electronic unit)
9a, 9b Mounting part 11a Close wall 13 Ceiling panel (close wall)
20 Lower case (cover member)
22a, 23a Hole 23a, 24a Relative wall R Ventilation path

Claims (2)

Multiple electronic units,
A storage box having a plurality of attachment parts to which the electronic unit is attached;
In an electrical junction box comprising a cover member attached to the storage box,
The attachment portion are each provided with at least a portion parallel to and closely wall intimate contact with at least a portion of the outer surface of the outer surface of the electronic unit,
When the cover member is attached to the storage box, the cover member includes a relative wall provided at a distance from the close wall, and forms a ventilation path through which gas passes between the relative wall and the close wall. and, and,
The relative wall is provided at a distance from the close wall of all mounting parts , and
An electrical junction box , wherein at least one of the close walls in close contact with at least a part of the outer surface of the electronic unit is in close contact with the entire flat surface of the outer surface of the electronic unit .   The electrical junction box according to claim 1, wherein a hole opened in the cover member is provided in the tight wall.

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