Electrical connection box and wire harness

An electrical connection box includes a case including a frame that holds electronic components and a cover that blocks an opening portion of the frame, a power supply connection portion provided inside the case, an external power supply being connected to the power supply connection portion, and a cover portion that covers the power supply connection portion from above, in which the cover portion has a hole portion that communicates a space portion on a side of the power supply connection portion with respect to the cover portion with a space portion above the cover portion inside the case, and is configured to detachably hold a component.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2015-171084 filed in Japan on Aug. 31, 2015.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electrical connection box and a wire harness.

2. Description of the Related Art

There has been an electrical connection box having a power supply connection portion to which an external power supply is connected. For example, Japanese Patent Application Laid-open No. 2013-17295 discloses a technology of an electrical connection box having a fuse block provided with a power supply input terminal electrically connected to a power supply.

When a power supply connection portion is exposed inside an electrical connection box, there is a possibility that a finger or a tool will touch a metal portion. It is effective to cover the power supply connection portion to inhibit the power supply connection portion from being unintentionally touched. However, when the power supply connection portion is merely covered, heat generated in the power supply connection portion is accumulated, which causes a temperature rise of the power supply connection portion.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an electrical connection box and a wire harness which allow compatibility between inhibiting the power supply connection portion from being unintentionally touched and suppressing a temperature rise of the power supply connection portion.

In order to achieve the above mentioned object, an electrical connection box according to one aspect of the present invention includes a case including a frame that holds an electronic component and a cover that blocks an opening portion of the frame; a power supply connection portion provided inside the case, an external power supply being connected to the power supply connection portion; and a cover portion that covers the power supply connection portion from above, wherein the cover portion has a hole portion that communicates a space portion on a side of the power supply connection portion with respect to the cover portion with a space portion above the cover portion inside the case, and is configured to detachably hold a component.

According to another aspect of the present invention, in the electrical connection box, it is preferable that the component detachably held by the hole portion is a fuse.

According to still another aspect of the present invention, in the electrical connection box, it is preferable that the cover portion includes a pair of wall portions extending in an up-down direction and facing each other with the power supply connection portion interposed therebetween, and covers the power supply connection portion from both sides by the pair of wall portions.

According to still another aspect of the present invention, a wire harness includes a case including a frame that holds an electronic component and a cover that blocks an opening portion of the frame; a power supply connection portion provided inside the case, an external power supply being connected to the power supply connection portion; a cover portion that covers the power supply connection portion from above; and an electric wire connected to the electronic component, wherein the cover portion has a hole portion that communicates a space portion on a side of the power supply connection portion with respect to the cover portion with a space portion above the cover portion inside the case, and is configured to detachably holds a component.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a detailed description will be given of an electrical connection box and a wire harness according to an embodiment of the present invention with reference to drawings. It should be noted that the invention is not restricted by the embodiment. In addition, a component in the embodiment below includes a component that can be easily assumed by those skilled in the art or substantially the same component.

Embodiment

An embodiment will be described with reference toFIG. 1toFIG. 11. The present embodiment relates to an electrical connection box and a wire harness.FIG. 1is a perspective view of the electrical connection box and the wire harness according to the embodiment of the present invention,FIG. 2is a perspective view of a frame according to the embodiment,FIG. 3is a perspective view of a lower cover according to the embodiment,FIG. 4is a perspective view illustrating an inside of the electrical connection box according to the embodiment,FIG. 5is a perspective view illustrating a power supply connection portion according to the embodiment,FIG. 6is a perspective view illustrating the power supply connection portion and a holding member according to the embodiment,FIG. 7is a plan view illustrating the inside of the electrical connection box according to the embodiment,FIG. 8is a cross-sectional view related to the power supply connection portion and a cover portion according to the embodiment,FIG. 9is a longitudinal sectional view related to the power supply connection portion and the cover portion according to the embodiment, andFIG. 10is a rear view illustrating a fixed state of an electric wire according to the embodiment.

An electrical connection box1illustrated inFIG. 1is included in a wire harness WH together with an electric wire W. The wire harness WH is installed in a vehicle such as an automobile to connect respective devices installed in the vehicle to each other. The wire harness WH includes a plurality of electric wires W used for power supply or signal communication. One end of each of the electric wires W is connected to an electronic component stored inside the electrical connection box1. The other end of each of the electric wires W is connected to each device (external equipment) such as an electrical component or a battery through a connector and the like.

The electrical connection box1is referred to as a junction box, a fuse box, a relay box, or the like in some cases. However, in the present embodiment, the “electrical connection box” is used as a general term. The electrical connection box1includes a case2as a housing that accommodates the electronic component. The case2includes a frame21, an upper cover22, and a lower cover23. The frame21, the upper cover22, and the lower cover23of the present embodiment are formed using synthetic resin. As illustrated inFIG. 2, an external wall24of the frame21has a shape of a square tube, and both ends of a cylindrical shape in an axial direction are opened. In other words, the external wall24of the frame21has a cross-sectional shape substantially corresponding to a polygon, and is a tubular portion, both ends of which in the axial direction are opened. The electrical connection box1of the present embodiment is installed in the vehicle such that one opening portion of the frame21(hereinafter referred to as an “upper opening portion”)24afaces upward, and the other opening portion (hereinafter referred to as a “lower opening portion”)24bfaces downward. In description below, a direction such as an “up-down direction” indicates a direction in a state in which the electrical connection box1is installed in the vehicle. The upper opening portion24ais blocked by the upper cover22, and the lower opening portion24bis blocked by the lower cover23.

The frame21includes a partition wall25that partitions an inside of the external wall24. The partition wall25is molded integrally with the external wall24. The partition wall25partitions an internal space of the external wall24into a plurality of accommodation space portions26. Each of the accommodation space portions26is opened toward at least one of an upper side and a lower side. The electronic component is inserted into the accommodation space portions26from opening portions of the accommodation space portions26. A lock mechanism such as engaged hook portions24cand25ais provided on an internal wall surface of the external wall24and the partition wall25. The electronic component (including a block corresponding to an assembly of electronic components) accommodated in the accommodation space portions26inside the frame21is locked by the lock mechanism.

The frame21includes a first upper tubular portion24dand a second upper tubular portion24e. The upper tubular portions24dand24eare half cylindrical components protruding from the external wall24. The upper tubular portions24dand24eare formed to surround the opening portions provided in the external wall24. As illustrated inFIG. 3, the lower cover23includes a first lower tubular portion23band a second lower tubular portion23ccorresponding to the upper tubular portions24dand24e. A main body portion23aof the lower cover23is fit to the lower opening portion24bof the frame21to block the lower opening portion24b. The lower tubular portions23band23claterally protrude from the main body portion23a. Each of the lower tubular portions23band23cis a half cylindrical component. The first lower tubular portion23bforms an insertion hole having a circular cross-section together with the first upper tubular portion24d. The second lower tubular portion23cforms an insertion hole having a circular cross-section together with the second upper tubular portion24e. These insertion holes allow an internal space and an external space of the case2to communicate with each other. The electric wires W are inserted into these insertion holes.

As illustrated inFIG. 4, various electronic components are held inside the frame21. The electrical connection box1of the present embodiment accommodates a plurality of relays3and fuses4therein. In addition, as illustrated inFIG. 5, a power supply connection portion5to which a terminal10is fixed is provided inside the frame21. The power supply connection portion5includes a bus bar6, a screw7, and a nut8. The bus bar6is a plate-shaped member formed using conductive metal. The bus bar6is fixed to the frame21through a resin holding member9(seeFIG. 4). The relays3and the fuses4are electrically connected to the bus bar6. The terminal10is fixed to one end of the bus bar6in a longitudinal direction. The terminal10is a terminal for connection with an external power supply. The terminal10is connected to the external power supply such as a battery through the electric wire W. A through-hole into which a male screw portion of the screw7can be inserted is formed in the bus bar6and the terminal10. The male screw portion of the screw7is inserted into the through-hole of the terminal10and the through-hole of the bus bar6and screwed with the nut8. In other words, the nut8is fastened to the screw7with the terminal10and the bus bar6interposed between the nut8and a head portion7aof the screw7. Power from an external power supply is supplied to an electronic component inside the case2through the electric wires W, the terminal10, and the bus bar6.

The holding member9illustrated inFIG. 6and other FIGS. has a function of covering the bus bar6and a function of holding the bus bar6. The holding member9covers the bus bar6from both surface sides and holds the bus bar6. In addition, the holding member9is detachably fixed to the frame21by the lock mechanism. As illustrated inFIG. 6, the holding member9includes a pair of wall portions9aand9bthat covers the power supply connection portion5. Herein, in the present specification, a direction along a central axis line of the screw7and orthogonal to the up-down direction is referred to as a “longitudinal direction”, and a direction orthogonal to each of the longitudinal direction and the up-down direction is referred to a “cross direction”. The pair of wall portions9aand9bface each other in the cross direction with the power supply connection portion5and the terminal10interposed therebetween. The first wall portion9acovers the power supply connection portion5and the terminal10from one side in the cross direction, and the second wall portion9bcovers the power supply connection portion5and the terminal10from the other side in the cross direction.

Herein, when a metal portion of the terminal10or the power supply connection portion5is exposed inside the case2, there is a possibility that a tool or a finger of an operator will touch the metal portion during operation. It is desirable to inhibit the metal portion from being carelessly touched in advance. As described below with reference toFIG. 2,FIG. 7, and other FIGS. the electrical connection box1of the present embodiment includes a cover portion30that covers the power supply connection portion5from above. The cover portion30has an electrical insulating property. The cover portion30covers the power supply connection portion5and the terminal10integrally, and protects the terminal10and the power supply connection portion5from being touched by the finger of the operator or the tool. Further, the cover portion30includes a hole portion33that releases heat generated in the power supply connection portion5. The hole portion33releases heat inside the cover portion30upward to suppress a temperature rise of the terminal10and the power supply connection portion5. Therefore, the cover portion30of the present embodiment may inhibit the power supply connection portion5from being unintentionally touched by the tool or the like while suppressing a temperature rise of the power supply connection portion5.

As illustrated inFIG. 2, the cover portion30of the present embodiment is a portion of the frame21, and is molded integrally with the external wall24and the partition wall25. As illustrated inFIG. 2andFIG. 7, the cover portion30includes an external wall portion31and a plurality of partition portions32(a first partition portion32a, a second partition portion32b, a third partition portion32c, a fourth partition portion32d, and a fifth partition portion32e).

The external wall portion31is a hollow tubular portion, a cross-sectional shape of which is a rectangular shape, and extends in the up-down direction. As illustrated inFIG. 7, the external wall portion31includes a front wall portion31a, a rear wall portion31b, a first side wall portion31c, and a second side wall portion31d. The front wall portion31aand the rear wall portion31bface each other in the longitudinal direction. As illustrated inFIG. 9, the front wall portion31ais a wall portion facing the bus bar6with the terminal10interposed therebetween, that is, a wall portion facing the head portion7aof the screw7in the longitudinal direction. The rear wall portion31bis a wall portion facing the front wall portion31awith the terminal10and the power supply connection portion5interposed therebetween. The first side wall portion31cand the second side wall portion31dface each other in the cross direction. The first side wall portion31cconnects one-side ends of the front wall portion31aand the rear wall portion31bin the longitudinal direction, and the second side wall portion31dconnects the other-side ends of the front wall portion31aand the rear wall portion31bin the longitudinal direction.

As illustrated inFIG. 7andFIG. 9, the internal space surrounded by the external wall portion31is partitioned into a plurality of hole portions33(a first hole portion33a, a second hole portion33b, a third hole portion33c, and a fourth hole portion33d) by the partition portions32. In addition, a front communication hole portion36ais provided between the first partition portion32aand the front wall portion31a, and a rear communication hole portion36bis provided between the fifth partition portion32eand the rear wall portion31b. The partition portions32are partition walls perpendicular to the longitudinal direction. The first hole portion33ato the third hole portion33cdetachably hold an auxiliary fuse4. The fourth hole portion33ddetachably holds a temporarily detached fuse4during inspection or operation or while carrying the vehicle. The hole portions33a,33b,33c,33d,36a, and36ballow communication between a space portion38positioned on the power supply connection portion5side with respect to the cover portion30and a space portion39above the cover portion30inside the case2. The hole portions33a,33b,33c,33d,36a, and36bare through-holes penetrating the cover portion30in the up-down direction. A pair of engaged portions34(a first engaged portion34aand a second engaged portion34b) and a support35are provided in each of the hole portions33a,33b,33c, and33d.

As illustrated inFIG. 8, the engaged portion34is integrally formed with the external wall portion31. The engaged portion34includes a flexible main body341and a hook portion342provided at a distal end of the main body341. A base end of the main body341is connected to internal wall surfaces of the side wall portions31cand31d. The main body341extends upward from the base end. The hook portion342protrudes in the cross direction from the distal end of the main body341. Specifically, the hook portion342of the first engaged portion34aprotrudes toward the second engaged portion34bside, and the hook portion342of the second engaged portion34bprotrudes toward the first engaged portion34a. A gap is provided between the main body341and the side wall portions31cand31d. Therefore, the main body341is bent and deformed when the fuse4is inserted into the hole portion33, and allows the fuse4to pass between two hook portions342. As illustrated inFIG. 8, the hook portion342is engaged with a shoulder portion of the fuse4inserted into the hole portion33to hold the fuse4together with the support35.

The support35supports the fuse4from below. The support35is provided in a middle portion between the first engaged portion34aand the second engaged portion34b. The support35extends in the longitudinal direction, and connects adjacent partition portions32to each other. For example, as illustrated inFIG. 9, the support35of the third hole portion33cis connected to the third partition portion32cand the fourth partition portion32d.

As illustrated inFIG. 8andFIG. 9, the cover portion30covers the terminal10and the power supply connection portion5from above. As illustrated inFIG. 8, the second side wall portion31dof the cover portion30covers the terminal10and the power supply connection portion5from one side in the cross direction. As described in the foregoing, the wall portions9aand9bof the holding member9covers the terminal10and the power supply connection portion5from both sides in the cross direction. The second side wall portion31dcovers the wall portion9bfrom outside. As illustrated inFIG. 9, the front wall portion31aof the cover portion30covers the terminal10and the power supply connection portion5from a front side (a side of the head portion7aof the screw7). Meanwhile, the rear wall portion31bof the cover portion30covers the terminal10and the power supply connection portion5from a rear side (a side of the nut8).

As described above, the electrical connection box1and the wire harness WH of the present embodiment include the cover portion30that covers the power supply connection portion5from above. Therefore, the electrical connection box1and the wire harness WH of the present embodiment may inhibit the finger of the operator or the tool from unintentionally touching the terminal10and the power supply connection portion5. The cover portion30has the hole portion33that allows communication between the space portion38positioned on the power supply connection portion5side with respect to the cover portion30and the space portion39above the cover portion30inside the case2. Therefore, the electrical connection box1and the wire harness WH of the present embodiment may accelerate radiation of heat from the power supply connection portion5and the terminal10to suppress a temperature rise. Further, the hole portion33detachably holds the component (the fuse4in the present embodiment). Therefore, the electrical connection box1and the wire harness WH of the present embodiment achieve miniaturization by effectively utilizing a space above the power supply connection portion5to hold the component.

The cover portion30which has a heat radiation structure using a die cutting structure that fixes the auxiliary fuse4is provided in the electrical connection box1of the present embodiment. As the cover portion30is integrally formed with the frame21, a protection structure of the power supply connection portion5is achieved without causing increase of the number of components.

In addition, the cover portion30of the present embodiment includes a pair of wall portions (the front wall portion31aand the rear wall portion31b) which extend in the up-down direction and face each other with the power supply connection portion5interposed therebetween, and covers the power supply connection portion5from both sides using the pair of wall portions31aand31b. In other words, the cover portion30not only merely covers an upper part of the power supply connection portion5, but also covers the both sides at sides. Therefore, the cover portion30may appropriately inhibit the tool or the like from unintentionally touching the power supply connection portion5.

In addition, the cover portion30of the present embodiment protects the held fuse4from impact. As illustrated inFIG. 8, upper ends of the first side wall portion31cand the second side wall portion31dof the cover portion30protrudes up to an upper side than the fuse4accommodated in the hole portion33. Further, the cover portion30protects the fuse4using a dual structure provided between the side wall portions31cand31dand the engaged portions34aand34b. In addition, as illustrated inFIG. 9, the front wall portion31aand the rear wall portion31bprotrude up to an upper side than the fuse4accommodated in the hole portion33. Therefore, the cover portion30may protect the fuse4from an object that falls from above, or protect the fuse4when the cover portion30touches another object. In addition, as illustrated inFIG. 8, ribs37are provided on outer surfaces of the first side wall portion31cand the second side wall portion31d. The ribs37protect the fuse4by reinforcing the side wall portions31cand31d.

In addition, in the electrical connection box1of the present embodiment, the electric wires W are fixed to the frame21at two places as described with reference toFIG. 10. In this way, a shift in electric wires W is suppressed, and an improvement in fixing force is achieved. As illustrated inFIG. 10, the plurality of electric wires W connected to the electronic component inside the frame21is bound and allowed pass through the first upper tubular portion24d. The electric wires W are fixed to the first upper tubular portion24dby a binding band11. In the electrical connection box1of the present embodiment, the electric wires W are fixed by the binding band11at a plurality of places along the axial direction of the first upper tubular portion24d. In this way, a shift in the electric wires W is suppressed when an external force in a direction perpendicular to axes indicated by arrows Y1and Y2inFIG. 10acts on the electric wires W.

FIG. 11is a diagram illustrating a fixed state of electric wires according to a comparative example. In a case in which one fixed place by a binding band11is present as in the comparative example illustrated inFIG. 11, when an external force perpendicular to an axis acts on the electric wires W, the electric wires W are easily shifted by being inclined using the fixed place as a fulcrum. On the other hand, in the electrical connection box1of the present embodiment, the electric wires W are fixed by the binding band11at two places separated from each other in the axial direction. Therefore, a shift in the electric wires W using a fixed place as a fulcrum is suppressed. In addition, fixing power with respect to the electric wires W is improved by performing fixing by the binding band11at a plurality of places when compared to the comparative example in which one fixed place is present. Therefore, a shift in the electric wires W is suppressed even in the case of an external force in a different direction from a direction perpendicular to the axis, for example, an external force along the axial direction.

Modified Example of Embodiment

A modified example of the embodiment will be described. In the above embodiment, the cover portion30is formed integrally with the frame21. However, the cover portion30and the frame21may be different bodies. In this case, the cover portion30may be attached to and detached from the frame21, and may be attached to and detached from the holding member9. The cover portion30preferably has higher thermal conductivity than thermal conductivity of the frame21. The cover portion30may have a heat radiating fin. The ribs37may serve as the heat radiating fin.

An aspect of connection between the external power supply and the power supply connection portion5is not restricted to an example in the above embodiment. For example, a fixing means for fixing the terminal10is not restricted to the screw7and the nut8. For example, the electric wires W connected to the external power supply may be connected to the power supply connection portion5without the terminal10interposed therebetween.

Content disclosed in the above embodiment and the modified example may be appropriately combined and implemented.

An electrical connection box and a wire harness according to the present embodiment include a cover portion that covers a power supply connection portion from above. The cover portion has a hole portion that communicates a space portion on a side of the power supply connection portion with respect to the cover portion with a space portion above the cover portion inside the case, and detachably holds a component. The electrical connection box and the wire harness according to the present embodiment may allow compatibility between inhibiting the power supply connection portion from being unintentionally touched and suppressing a temperature rise of the power supply connection portion.