Large current fuse for direct power supply

Abstract

To prevent an appearance of a body and a cover from being impaired when a fusible body is melted by an overcurrent.SOLUTION: A large current fuse for direct power supply, includes: a fuse body 3 having a first fusible body 9; a body 4 made of synthetic resin and having a fusible body accommodating part 27 for accommodating the first fusible body 9; and a cover 5 made of synthetic resin for closing the fusible body accommodating portion 27. The fusible body accommodating portion 27 includes: a base wall part 28; a pair of side wall parts 29 and 30 extending orthogonally to the base wall part 28; and a reinforcing wall part 31 connecting both end parts of the side wall parts 29 and 30 on the opposite side to the base wall part 28. The base wall part 28, the pair of side wall parts 29 and 30, and the reinforcing wall part 31 surround the first fusible body 9 from four sides.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a large current fuse for direct connection to a power source, which is directly connected to a battery. [Background technology]

[0002] BACKGROUND ART As an example of a large current fuse for direct connection to a power source that is used in an automobile, for example, the large current fuse for direct connection to a power source described in Patent Document 1 is known.

[0003] As shown in Fig. 12, the large-current fuse 60 for direct connection to a power source in Patent Document 1 includes a fuse main body 61 electrically connected to a battery post of a battery (not shown), and a synthetic resin body 62 integrally molded with the fuse main body 61. The fuse main body 61 has a fusible element 63 that melts when an overcurrent occurs. The body 62 has a rectangular tubular fusible element housing portion 64 that houses most of the fusible element 63. The fusible element housing portion 64 has a short-side wall portion 64a located on the outside. This short-side wall portion 64a is molded integrally with a part of the fusible element 63, thereby holding the fusible element 63.

[0004] Another example of a large current fuse for direct connection to a power source that is used in automobiles is the large current fuse for direct connection to a power source described in Patent Document 2, for example.

[0005] As shown in FIG. 13, a high-current fuse 65 for direct power supply described in Patent Document 2 includes a fuse body 67 having a fusible body 66, a synthetic resin body 69 having a fusible body accommodating portion 68 for accommodating the fusible body 66, and a synthetic resin cover 70 that is inserted into a stepped portion 68a of the fusible body accommodating portion 68 to close the fusible body accommodating portion 68. The fusible body accommodating portion 68 has a short-side wall portion 68b located on the outside. This short-side wall portion 68b holds the fusible body 66 by being integrally formed with a part of the fusible body 66. Further, a body-side locking portion 71 is formed on the short-side wall portion 68b. The cover 70 has a base wall 72 orthogonal to the fuse body 67, and the base wall 72 has a cover-side locking portion 73 that protrudes in the insertion direction Y of the cover 70 from the inner surface of the base wall 72. This cover-side locking portion 73 locks to the body-side locking portion 71.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] In Patent Document 1, when the fusible body 63 is blown by an overcurrent, there is a risk that the appearance of the body 62 including the fusible body accommodating portion 68 may be damaged because the short-side wall portion 64a in close contact with a part of the fusible body 63 melts.

[0008] Further, in Patent Document 2, when the fusible body 66 is blown by an overcurrent, the short-side wall portion 68b in close contact with a part of the fusible body 66 melts, and in some cases, the cover 70 adjacent to the short-side wall portion 68b melts, so there is a risk that the appearance of the body 69 or the cover 70 may be damaged.

[0009] The present invention has been devised in view of the conventional situation, and one of its objects is to provide a high-current fuse for direct power supply that can suppress the body and cover from melting and damaging the appearance when the fusible element is blown by overcurrent.

Means for Solving the Problems

[0010] The present invention relates to a high-current fuse for direct power supply. The high-current fuse for direct power supply includes a fuse body that is electrically connected to a battery post of a battery via a power terminal and has a fusible element that melts due to overcurrent, and a synthetic resin body that is integrally formed with the fuse body and has a fusible element accommodating portion that surrounds the fusible element in a U shape from three sides and accommodates it, and a synthetic resin cover that is inserted into the fusible element accommodating portion and closes the fusible element accommodating portion and forms a U shape. The cover further has side walls extending from the side edges of the cover so as to cover the openings on the sides of the cover. The side walls of the cover have cover-side locking portions that extend in a direction not coinciding with the insertion direction of the cover. The cover-side locking portions are locked to body-side locking portions provided on the outer surface of the fusible element accommodating portion.

Effects of the Invention

[0011] According to the present invention, the fusible element of the fuse body is surrounded in a U shape from three sides by the fusible element accommodating portion of the body, and further, in a state where the fusible element accommodating portion is closed by the U-shaped cover, the fusible element does not contact the body and the cover. Therefore, it is possible to suppress the appearance of the body and the cover from being damaged when the fusible element is blown by overcurrent.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the high-current fuse for direct power supply of the present invention will be described with reference to the drawings. [First Embodiment] As shown in FIGS. 1, 3, and 4, a high-current fuse for direct power supply (hereinafter referred to as "high-current fuse") includes a fuse body 3 electrically connected to a battery post 1a of a battery 1 via a power supply terminal 2, a synthetic resin body 4 integrally formed with the fuse body 3, and a pair of synthetic resin covers 5 that respectively close a pair of soluble body accommodating portions 27 described later formed in the body 4.

[0014] Here, for convenience of explanation, three directions are defined in FIGS. 2 to 4. First, the direction along the left-right direction in FIGS. 2 to 4 is defined as the "width direction X of the fuse body 3". And the direction orthogonal to the width direction X of the fuse body 3 and from the front side to the back side in FIGS. 2 to 4 is defined as the "insertion direction Y of the cover 5". Further, the direction orthogonal to the width direction X of the fuse body 3 and the insertion direction Y of the cover 5 is defined as the "thickness direction Z of the fuse body 3".

[0015] As shown in FIG. 2, the fuse body 3 includes a power supply terminal plate 6 having a generally rectangular plate shape, a first connection terminal plate 7 and a second connection terminal plate 8 having a generally rectangular plate shape smaller than the power supply terminal plate 6, and a first soluble body 9 and a second soluble body 10 (corresponding to the "pair of soluble bodies" in the claims) having the same L-shaped.

[0016] A circular connection hole 11 is formed at one end 6a side of the power supply terminal plate 6 in the insertion direction Y of the cover 5.

[0017] As shown in FIG. 1, the power supply terminal 2 has a caulking hole 2a for inserting the battery post 1a, an adjustment screw 2b for adjusting the diameter of the caulking hole 2a, and a stud bolt 2c inserted into the connection hole 1l. This stud bolt 2c is screwed into a nut 12, and by this screwing, the power supply terminal plate 6 is electrically connected to the stud bolt 2c.

[0018] As shown in FIG. 2, the first connection terminal board 7 is disposed with a gap S1 therebetween from one side portion 6c of the power supply terminal board 6 on the other end 6b side of the power supply terminal board 6 in the insertion direction Y of the cover 5. A circular first bolt hole 13 is formed at a position near the other end 7b of the first connection terminal board 7. A stat bolt 14 is inserted into the first bolt hole 13 from the lower side in the thickness direction Z of the fuse body 3. As shown in FIGS. 1, 3, and 4, in a state where the stat bolt 14 is inserted into the first bolt hole 13, the shaft portion 14a of the stat bolt 14 protrudes above the first connection terminal board 7. The shaft portion 14a of the stat bolt 14 is inserted into a circular first hole 16a provided in the first terminal 16 of the alternator connection wire 15 and then screwed into a nut 17. By this screwing, the first connection terminal board 7 is electrically connected to an alternator (not shown) via the alternator connection wire 15 and the first terminal 16.

[0019] As shown in FIG. 2, the second connection terminal board 8 is disposed at a position symmetric to the first connection terminal board 7 in the width direction X of the fuse body 3. That is, the second connection terminal board 8 is disposed with a gap S2 therebetween from the other side portion 6d of the power supply terminal board 6 on the other end 6b side of the power supply terminal board 6 in the insertion direction Y of the cover 5. The gap S2 has the same width (width along the width direction X of the fuse body 3) as the gap S1. A circular second bolt hole 18 is formed at a position near the other end 8b of the second connection terminal board 8. A stat bolt 19 is inserted into the second bolt hole 18 from the lower side in the thickness direction Z of the fuse body 3. As shown in FIGS. 1, 3, and 4, in a state where the stat bolt 19 is inserted into the second bolt hole 18, the shaft portion 19a of the stat bolt 19 protrudes above the second connection terminal board 8. The shaft portion 19a of the stat bolt 19 is inserted into a circular second hole 21a provided in the second terminal 21 of the load connection wire 20 and then screwed into a nut 22. By this screwing, the second connection terminal board 8 is electrically connected to a load, such as electric equipment or a relay-fuse box, via the load connection wire 20 and the second terminal 21.

[0020] The first fusible element 9 (corresponding to the "fusible element" in the claims) melts due to self-heating when an overcurrent flows through the high-current fuse. As shown in FIG. 2, the first fusible element 9 has a thin, continuous elongated portion 9a extending along the insertion direction Y of the cover 5, and a short portion 9b that is perpendicular to the elongated portion 9a and shorter than the elongated portion 9a. The elongated portion 9a is connected to one end 7a of the first connection terminal board 7. Meanwhile, the short portion 9b is connected to the power supply terminal board 6. The elongated portion 9a has a crimping piece 23 and a wide piece 24 that is wider than the crimping piece 23. A metal tip 25, such as a tin or lead alloy tip, is crimped to the crimping piece 23.

[0021] The second fusible element 10 (corresponding to the "fusible element" in the claims), like the first fusible element 9, melts due to self-heating when an overcurrent flows through the high-current fuse. The second fusible element 10 is configured by replacing the wide piece 24 of the first fusible element 9 with a crimping piece 23 and a metal tip 25. Therefore, the second fusible element 10 has the same elongated portion 9a, short portion 9b, and pair of crimping pieces 23 as the first fusible element 9. The reason for replacing the crimping piece 23 and metal tip 25 is that the second fusible element 10 side is the discharge side of the charging current from the battery 1 and has a smaller capacity than the first fusible element 9 side, which contributes to charging, so there is no need to provide the wide piece 24. The second fusible element 10 is arranged symmetrically with the first fusible element 9 in the width direction X of the fuse body 3, with the connection hole 11 in between. The elongated portion 9a of the second fusible element 10 is connected to one end 8a of the second connection terminal plate 8. On the other hand, the short portion 9b of the second fusible element 10 is connected to the power supply terminal plate 6.

[0022] As shown in FIGS. 3 and 4, the body 4 is integrally formed with the fuse body 3 over both surfaces of the body 4 in a region excluding the periphery of the connection hole 11 of the power supply terminal board 6, the periphery of the first bolt hole 13 of the first connection terminal board 7, and the periphery of the second bolt hole 18 of the second connection terminal board 8. Heat dissipation fins 26 are formed at portions of the upper side (the upper side in FIGS. 3 and 4) of the body 4 that are located between the stator bolts 14 and 19 and at portions adjacent to this portion. The heat dissipation fins 26 have a plurality of thin heat dissipation plates 26a aligned in the width direction X of the fuse body 3. Since the plurality of heat dissipation plates 26a increase the surface area of the body 4, the heat dissipation effect against the heat generated in the power supply terminal board 6 can be improved.

[0023] Also, as shown in FIGS. 3 and 4, the body 4 has a pair of fusible body accommodating portions 27 disposed on both sides of the connection hole 11 in the width direction X of the fuse body 3. The pair of fusible body accommodating portions 27 have the same shape and accommodate the first fusible body 9 and the second fusible body 10, respectively. Since the pair of fusible body accommodating portions 27 have the same shape, the pair of covers 5 that close the pair of fusible body accommodating portions 27 also have the same shape.

[0024] As shown in FIG. 3, the fusible body accommodating portion 27 has a rectangular cylindrical shape (square cylindrical shape) that surrounds and accommodates the first fusible body 9 and the second fusible body 10 from all sides, and the long side is parallel to the insertion direction Y of the cover 5. The fusible body accommodating portion 27 has a base wall portion 28 facing the insertion direction Y of the cover 5, and a pair of outer and inner side wall portions 29 and 30 extending from both ends of the base wall portion 28 in a direction opposite to the insertion direction Y of the cover 5 so as to be orthogonal to the base wall portion 28, and a reinforcing wall portion 31 that connects the ends of the side wall portions 29 and 30 on the side opposite to the base wall portion 28 to reinforce the fusible body accommodating portion 27.

[0025] The base wall portion 28 is generally in the shape of a rectangular plate. Also, the pair of side wall portions 29, 30 are generally in the shape of rectangular plates with their long sides extending along the insertion direction Y of the cover 5. The length of the base wall portion 28 along the thickness direction Z of the fuse body 3 is the same as the length of the pair of side wall portions 29, 30 along the thickness direction Z of the fuse body 3. As shown in FIG. 3, at the upper end portion 32 and the lower end portion 33 where the base wall portion 28 and the pair of side wall portions 29, 30 are continuously U-shaped in the thickness direction Z of the fuse body 3, a pair of stepped portions 34 that are recessed stepwise from the upper end portion 32 and the lower end portion 33 toward the inside of the base wall portion 28 and the pair of side wall portions 29, 30 are formed. The pair of stepped portions 34 are continuously U-shaped so as to open toward the cover 5 side, and the upper wall 38 and the lower wall 39 of the cover 5 are inserted into the pair of stepped portions 34 along the insertion direction Y of the cover 5.

[0026] Also, as shown in FIGS. 3 and 4, on the outer surface of the outer side wall portion 29, a protrusion 35 that protrudes outward along the width direction X of the fuse body 3 from this outer surface is formed. That is, on the outer surface of the outer side wall portion 29, a protrusion 35 that protrudes outward along a direction orthogonal to the insertion direction Y of the cover 5 and the thickness direction Z of the fuse body 3 is formed. More specifically, instead of providing a protrusion midway in the direction from the base wall 37 of the cover 5 toward the insertion direction Y of the cover 5, by providing the protrusion 35 that protrudes in the width direction X of the fuse body 3, which is a direction that does not coincide with the insertion direction Y of the cover 5, a synthetic resin portion is not provided in the vicinity of the first fusible body 9 and the second fusible body 10.

[0027] The protrusion 35 generally has a rectangular parallelepiped shape and forms a trapezoid when viewed from the thickness direction Z of the fuse body 3. The protrusion 35 is located on the base wall portion 28 side in the insertion direction Y of the cover 5 and has a body-side locking portion 35a which is a surface orthogonal to the side wall portion 29. A cover-side locking portion 41a, which will be described later, provided on the side wall 40 of the cover 5 is locked to the body-side locking portion 35a. Further, the protrusion 35 has an inclined surface 35b located on the reinforcing wall portion 31 side in the insertion direction Y of the cover 5. The inclined surface 35b is inclined such that the width along the width direction X of the fuse body 3 increases as the cover 5 advances in the insertion direction Y. When the cover 5 is inserted in the insertion direction Y of the cover 5, the tip portion 40a of the side wall 40 of the cover 5 rides on the inclined surface 35b.

[0028] Further, a stopper portion 36 for restricting the insertion of the cover 5 is formed at a position on the outer surface of the outer side wall portion 29 closer to the stud bolts 14 and 19 than the protrusion 35 by abutting against the tip portion 40a of the side wall 40 of the cover 5. The stopper portion 36 is generally formed in a prismatic shape and extends in the thickness direction Z of the fuse body 3.

[0029] Also, as shown in FIG. 3, the inner side wall portion 30 extends from the base wall portion 28 beyond the outer surface of the reinforcing wall portion 31 in the direction opposite to the insertion direction Y of the cover 5. On the other hand, the outer side wall portion 29 extends from the base wall portion 28 to a position flush with the outer surface of the reinforcing wall portion 31 in the direction opposite to the insertion direction Y of the cover 5.

[0030] The reinforcing wall portion 31 maintains the rigidity of the fusible body accommodating portion 27 during the molding of the synthetic resin body 4 and prevents warping of the pair of side wall portions 29, 30. The reinforcing wall portion 31 has a rectangular plate shape. The length of the reinforcing wall portion 31 along the thickness direction Z of the fuse body 3 is the same as the length along the thickness direction Z of the fuse body 3 of the portion excluding the pair of stepped portions 34 among the base wall portion 28 and the pair of side wall portions 29, 30. Note that the length of the reinforcing wall portion 31 along the thickness direction Z of the fuse body 3 can be shortened as long as it is possible to ensure the rigidity of the fusible body accommodating portion 27 and prevent warping of the pair of side wall portions 29, 30. Also, when the rigidity of the fusible body accommodating portion 27 can be sufficiently ensured during the molding of the body 4, the reinforcing wall portion 31 can be omitted. In this case, the base wall portion 28 and the pair of side wall portions 29, 30 of the fusible body accommodating portion 27 will surround and accommodate the first fusible body 9 in a U shape from three sides.

[0031] The cover 5 has a base wall 37 parallel to the thickness direction Z of the fuse body 3, an upper wall 38 extending orthogonally from the upper edge portion 37a of the base wall 37 in the thickness direction Z of the fuse body 3, and a lower wall 39 extending parallel to the upper wall 38 from the lower edge portion 37b of the base wall 37 in the thickness direction Z of the fuse body 3.

[0032] The base wall 37 has a rectangular plate shape with the long side extending along the width direction X of the fuse body 3. When the reinforcing wall portion 31 of the fusible body accommodating portion 27 is omitted as described above, the base wall 37 closes a part of the opening of the fusible body accommodating portion 27.

[0033] The upper wall 38 has a rectangular plate shape with the long side extending along the insertion direction Y of the cover 5.

[0034] The lower wall 39 has the same shape as the upper wall 38 and has a rectangular plate shape with the long side extending along the insertion direction Y of the cover 5.

[0035] The base wall 37, the upper wall 38, and the lower wall 39 configured in this way form a U shape, which is the basic part of the cover 5.

[0036] As shown in FIG. 3, the side edge 37c of the base wall 37 is located outside the outer end faces 38a and 39a of the upper wall 38 and the lower wall 39. The cover 5 further has a side wall 40 extending orthogonally from the side edge 37c of the base wall 37 so as to cover a part of the opening on the outer side of the cover 5. Also, the side wall 40 is spaced apart from the upper wall 38 and the lower wall 39 with a predetermined gap therebetween and is orthogonal to both the upper wall 38 and the lower wall 39. The side wall 40 is formed in a rectangular plate shape smaller than the upper wall 38 and the lower wall 39. The length of the side wall 40 along the insertion direction Y of the cover 5 is shorter than the lengths of the upper wall 38 and the lower wall 39 along the insertion direction Y of the cover 5. Further, as shown in FIGS. 6(a) to 6(c), an inclined portion 40b is formed inside the tip portion 40a of the side wall 40. This inclined portion 40b is inclined such that the width along the width direction X of the fuse body 3 decreases as it goes in the insertion direction Y of the cover 5.

[0037] An elongated rectangular slot 41 is formed at the central portion of the side wall 40 in the thickness direction Z of the fuse body 3, and the slot 41 extends from the side edge 37c of the base wall 37 to the vicinity of the tip portion 40a of the side wall 40. The slot 41 has a cover-side locking portion 41a which is an end face orthogonal to the insertion direction Y of the cover 5. That is, the slot 41 has a cover-side locking portion 41a parallel to the base wall 37. The cover-side locking portion 41a locks to the body-side locking portion 35a of the protrusion 35 provided on the side wall portion 29 outside the body 4. Also, the side wall 40 is a part of the synthetic resin cover 5 and is formed to be elastically deformable in the direction approaching the upper wall 38 and the lower wall 39 and in the direction away from the upper wall 38 and the lower wall 39.

[0038] Also, as shown in FIG. 5, the height H of the stepped portion 34 along the thickness direction Z of the fuse body 3 is larger than the thicknesses T1 and T2 of the upper wall 38 and the lower wall 39 along the thickness direction Z of the fuse body 3. The thicknesses T1 and T2 have the same thickness. Since the height H of the stepped portion 34 is larger than the thicknesses T1 and T2 of the upper wall 38 and the lower wall 39 in this way, the upper wall 38 and the lower wall 39 are suppressed from detaching from the body 4 beyond the stepped portion 34.

[0039] Also, as shown in FIG. 5, when the upper wall 38 and the lower wall 39 of the cover 5 are inserted into the pair of upper and lower stepped portions 34 of the soluble body accommodating portion 27, the lower surface 38b of the upper wall 38 and the upper surface 39b of the lower wall 39 are in contact with the bottom surface 34a of each stepped portion 34. By this contact, the cover 5 is fixed to the body 4.

[0040] Next, with reference to FIGS. 4 and 6, the insertion process of the cover 5 into the soluble body accommodating portion 27 of the body 4 will be described.

[0041] First, as shown in FIG. 6(a), the cover 5 is inserted along the insertion direction Y of the cover 5. Then, after the inclined portion 40b of the tip portion 40a of the side wall 40 is lifted along the inclined surface 35b of the protrusion 35, as shown in FIG. 6(b), the tip portion 40a of the side wall 40 rides on the protrusion 35. Due to this riding on the protrusion 35, the side wall 40 elastically deforms in a direction away from the upper wall 38. Then, when the cover 5 is further inserted along the insertion direction Y of the cover 5, as shown in FIG. 6(c), the side wall 40 approaches the upper wall 38 and returns to the position before elastic deformation. At this time, as shown in FIG. 4, the protrusion 35 of the body 4 is located within the slot 41 of the side wall 40, and the cover-side locking portion 41a is locked to the body-side locking portion 35a.

[0042] As described above, in the first embodiment, the body 4 made of synthetic resin has a soluble body accommodating portion 27 that can accommodate the first soluble body 9 and the second soluble body 10 in a U shape from three sides. Further, the cover 5 made of synthetic resin has a U shape that closes the soluble body accommodating portion 27. In a state where the U-shaped soluble body accommodating portion 27 is closed by the U-shaped cover 5, the first soluble body 9 and the second soluble body 10 do not contact the base wall portion 28, the pair of side wall portions 29, 30 of the soluble body accommodating portion 27, the base wall 37, the upper wall 38, and the lower wall 39 of the cover 5. Therefore, even when the first soluble body 9 or the second soluble body 10 is melted by an overcurrent, it is possible to suppress the body 4 including the soluble body accommodating portion 27 and the cover 5 from melting and damaging the appearance of the body 4 and the cover 5.

[0043] Furthermore, the cover 5 further has side walls 40 extending from the side edges 37c of the base wall 37 of the cover 5 so as to cover the openings on the sides of the cover 5, and these side walls 40 have cover-side locking portions 41a extending in a direction not coinciding with the insertion direction Y of the cover 5. The cover-side locking portions 41a are not provided in the insertion direction Y of the cover 5 as viewed from the base wall 37. And the cover-side locking portions 41a are locked to the body-side locking portions 35a provided on the outer surface of the soluble body accommodating portion 27. Since the cover-side locking portions 41a are locked to the body-side locking portions 35a outside the soluble body accommodating portion 27 in this way, the body-side locking portions 35a and the cover-side locking portions 41a do not interfere with the first soluble body 9 and the second soluble body 10. Therefore, even if the first soluble body 9 and the second soluble body 10 are melted by overcurrent, it is possible to suppress the body-side locking portions 35a and the cover-side locking portions 41a from melting and damaging the appearance of the body 4 and the cover 5.

[0044] Also, in the first embodiment, the soluble body accommodating portion 27 has a base wall portion 28 surrounding the first soluble body 9 and the second soluble body 10 in a rectangular shape from four sides, a pair of side wall portions 29, 30, and a reinforcing wall portion 31. And even when the first soluble body 9 and the second soluble body 10 are surrounded from four sides, the first soluble body 9 and the second soluble body 10 do not contact the base wall portion 28, the pair of side wall portions 29, 30, and the reinforcing wall portion 31. Also, even when the soluble body accommodating portion 27 having such a base wall portion 28 etc. is closed by the cover 5, the first soluble body 9 and the second soluble body 10 do not contact the base wall portion 28, the pair of side wall portions 29, 30, the reinforcing wall portion 31 of the soluble body accommodating portion 27 in the body 4, and the upper wall 38 and the lower wall 39 of the cover 5. Therefore, even if the first soluble body 9 and the second soluble body 10 are melted by overcurrent, it is possible to suppress the appearance of the body 4 and the cover 5 from being damaged.

[0045] Furthermore, in the first embodiment, the first soluble body 9 and the second soluble body 10 have substantially the same L-shaped configuration, and are arranged symmetrically with respect to each other with the connection hole 11 therebetween. Also, the pair of soluble body accommodating portions 27 have the same shape, and are arranged symmetrically so as to accommodate the first soluble body 9 and the second soluble body 10 respectively. Furthermore, the cover 5 has the same shape, and closes the pair of soluble body accommodating portions 27 respectively. Therefore, even if one cover 5 is turned upside down to close the opposite soluble body accommodating portion 27, incorrect assembly of the cover 5 can be prevented. Also, since the pair of covers 5 are formed as common components, the types of components of the high-current fuse can be reduced, and the manufacturing cost of the high-current fuse can be reduced.

[0046] Also, in the first embodiment, the height H of the stepped portion 34 along the thickness direction Z of the fuse body 3 is greater than the thicknesses T1 and T2 of the upper wall 38 and the lower wall 39 along the thickness direction Z of the fuse body 3. For this reason, it is possible to suppress the upper wall 38 and the lower wall 39 from getting over the stepped portion 34 and shifting and detaching in the width direction X of the fuse body 3.

[0047] Also, in the first embodiment, when the upper wall 38 and the lower wall 39 of the cover 5 are inserted into the pair of upper and lower stepped portions 34 of the soluble body accommodating portion 27, the lower surface 38b of the upper wall 38 and the upper surface 39b of the lower wall 39 are in contact with the bottom surface 34a of each stepped portion 34. By this contact, the cover 5 can be fixed to the body 4. 〔Second Embodiment〕 In the second embodiment, the direction along the left-right direction in FIGS. 7 and 8 is defined as the "insertion direction Y of the cover 42". And the direction orthogonal to the insertion direction Y of the cover 42 and from the front side to the back side in FIGS. 7 and 8 is defined as the "longitudinal direction P of the elongated portion 9a (see FIG. 2)". Furthermore, the direction orthogonal to the insertion direction Y of the cover 42 and the longitudinal direction P of the elongated portion 9a is defined as the "thickness direction Z of the fuse body 3". Note that, in the present embodiment, the insertion direction Y of the cover 42 (the left cover 42 in FIGS. 7 and 8) for the soluble body accommodating portion 43 in which the first soluble body 9 is accommodated is illustrated, but the insertion direction of the other cover 42 is the opposite side to the insertion direction Y.

[0048] Also, as described above, in the first embodiment, the wall of the soluble body accommodating portion 27 facing the insertion direction Y of the cover 5 is defined as the "base wall portion 28", but in the second embodiment, the wall of the soluble body accommodating portion 43 facing the insertion direction Y of the cover 42 is defined as the "base wall portion 44".

[0049] As shown in FIG. 7, the soluble body accommodating portion 43 has a rectangular cylindrical shape surrounding the first soluble body 9 from all sides, and the long side is parallel to the longitudinal direction P of the elongated portion 9a. The soluble body accommodating portion 43 includes a base wall portion 44 facing the insertion direction Y of the cover 42, and a pair of outer and inner side wall portions 45, 46 extending from both ends of the base wall portion 44 in a direction opposite to the insertion direction Y of the cover 42 so as to be orthogonal to the base wall portion 44, and a reinforcing wall portion 47 that connects the ends of the side wall portions 45, 46 on the side opposite to the base wall portion 44 to reinforce the soluble body accommodating portion 43.

[0050] The base wall portion 44 has a generally rectangular plate shape with the long side extending along the longitudinal direction P of the elongated portion 9a. Also, the pair of side wall portions 45, 46 have a generally rectangular plate shape. The length of the base wall portion 44 along the thickness direction Z of the fuse body 3 is the same as the length of the pair of side wall portions 45, 46 along the thickness direction Z of the fuse body 3. As shown in FIG. 7, at the upper end portion 48 and the lower end portion 49 where the base wall portion 44 and the pair of side wall portions 45, 46 are continuously U-shaped in the thickness direction Z of the fuse body 3, a pair of stepped portions 50 are formed that are recessed stepwise from the upper end portion 48 and the lower end portion 49 to the inside of the base wall portion 44 and the pair of side wall portions 45, 46. The upper wall 55 and the lower wall 56 of the cover 42 are inserted along the insertion direction Y of the cover 42 into the pair of stepped portions 50.

[0051] Also, at a position on the side of the reinforcing wall portion 47 among the portions corresponding to the inner side wall portion 46 of each stepped portion 50, a stepped portion side locking portion 51 is formed, and the stepped portion side locking portion 51 is a concave portion in which the inner surface 50b of each stepped portion 50 is recessed rectangularly outward.

[0052] Further, on the outer surface of the outer side wall portion 45, a protrusion 52 is formed that protrudes outward along the longitudinal direction P of the elongated portion 9a from this outer surface. That is, on the outer surface of the outer side wall portion 45, a protrusion 52 is formed that protrudes outward along a direction orthogonal to the thickness direction Z of the fuse body 3 and the insertion direction Y of the cover 42.

[0053] The protrusion 52 generally has a rectangular parallelepiped shape and forms a trapezoid when viewed from the thickness direction Z of the fuse body 3. The protrusion 52 is located on the base wall portion 44 side in the insertion direction Y of the cover 42 and has a body-side locking portion 52a that is a surface orthogonal to the side wall portion 45. A cover-side locking portion 58a, which will be described later, provided on the side wall 57 of the cover 42 locks to this body-side locking portion 52a. Further, the protrusion 52 has an inclined surface 52b located on the reinforcing wall portion 47 side in the insertion direction Y of the cover 5. The inclined surface 52b is inclined such that the width along the longitudinal direction P of the elongated portion 9a increases as the cover 42 advances in the insertion direction Y of the cover 42. When the cover 42 is inserted in the insertion direction Y of the cover 42, the tip portion 57a of the side wall 57 of the cover 42 rides up on the inclined surface 52b.

[0054] Furthermore, at a position on the outer surface of the outer side wall portion 45 closer to the connection hole 11 than the protrusion 52, a stopper portion 53 is formed that restricts the insertion of the cover 42 by the tip portion 57a of the side wall 57 of the cover 42 abutting thereon. The stopper portion 53 is generally formed in a prismatic shape and extends in the thickness direction Z of the fuse body 3.

[0055] The reinforcing wall portion 47 has a rectangular plate shape with its long side extending along the longitudinal direction P of the elongated portion 9a. The length of the reinforcing wall portion 47 along the thickness direction Z of the fuse body 3 is the same as the length of the fuse body 3 along the thickness direction Z of the portion excluding the pair of stepped portions 50 of the base wall portion 44 and the pair of side wall portions 45, 46. Similar to the first embodiment, the length of the reinforcing wall portion 47 along the thickness direction Z of the fuse body 3 can be shortened and, when not required, can also be omitted.

[0056] The cover 42 has a base wall 54 facing the insertion direction Y of the cover 42, an upper wall 55 extending orthogonally from the upper edge of the base wall 54 on the upper side in the thickness direction Z of the fuse body 3, and a lower wall 56 extending parallel to the upper wall 55 from the lower edge of the base wall 54 on the lower side in the thickness direction Z of the fuse body 3.

[0057] The base wall 54 is in the shape of a rectangular plate with its long side extending along the longitudinal direction P of the elongated portion 9a. When the reinforcing wall portion 47 of the fusible body accommodating portion 43 is omitted as described above, the base wall 54 closes a part of the opening of the fusible body accommodating portion 43.

[0058] The upper wall 55 is in the shape of a rectangular plate with its long side extending along the longitudinal direction P of the elongated portion 9a.

[0059] The lower wall 56 has the same shape as the upper wall 55 and is in the shape of a rectangular plate with its long side extending along the longitudinal direction P of the elongated portion 9a.

[0060] The base wall 54, the upper wall 55, and the lower wall 56 configured as described above form a U-shaped basic part of the cover 42.

[0061] As shown in FIG. 7, the side edge 54c of the base wall 54 is located outside the outer end faces 55a and 56a of the upper wall 55 and the lower wall 56. The cover 42 has side walls 57 extending orthogonally from the side edge 54c of the base wall 54 so as to cover the outer opening of the cover 42. Further, the side walls 57 are spaced apart from the upper wall 55 and the lower wall 56 via a predetermined gap and are orthogonal to both the upper wall 55 and the lower wall 56. The side walls 57 are formed in the shape of rectangular plates. The length of the side walls 57 along the insertion direction Y of the cover 42 is the same as the lengths of the upper wall 55 and the lower wall 56 along the insertion direction Y of the cover 42. Also, as shown in FIGS. 10(a) to 10(c), an inclined portion 57b is formed inside the tip portion 57a of the side walls 57. This inclined portion 57b is inclined such that the width along the longitudinal direction P of the elongated portion 9a decreases as it goes in the insertion direction Y of the cover 5.

[0062] In the central portion of the side wall 57 in the thickness direction Z of the fuse body 3, an elongated rectangular slot 58 is formed, and this slot 58 extends from the side edge 54c of the base wall 54 to the vicinity of the tip 57a of the side wall 57. The slot 58 has a cover-side locking portion 58a which is an end face orthogonal to the insertion direction Y of the cover 42. That is, the slot 58 has a cover-side locking portion 58a parallel to the base wall 54. The cover-side locking portion 58a locks to the body-side locking portion 52a of the protrusion 52 provided on the side wall portion 45 outside the body 4. Further, the side wall 57 is a part of the synthetic resin cover 42 and is formed so as to be elastically deformable in the direction approaching the upper wall 55 and the lower wall 56 and in the direction separating from the upper wall 55 and the lower wall 56.

[0063] Also, a cover-side locking hook portion 59 is formed at the corner portion 55c located on the side opposite to the side wall 57 among the two corner portions 55b and 55c on the tip 55f side of the upper wall 55. The cover-side locking hook portion 59 has a rod-shaped portion 59a and a claw portion 59b provided at the tip of the rod-shaped portion 59a. The rod-shaped portion 59a extends from the corner portion 55c in the direction opposite to the insertion direction Y of the cover 42 and is spaced apart from the inner portion 55d of the upper wall 55 through a predetermined gap. The rod-shaped portion 59a is formed so as to be elastically deformable in the direction approaching the inner portion 55d of the upper wall 55 and also in the direction separating from the inner portion 55d of the upper wall 55. As shown in FIG. 8, the claw portion 59b is inclined outward from the tip of the rod-shaped portion 59a, and the tip has a shape corresponding to the outer corner portion 51a of the step portion side locking portion 51. As shown in FIGS. 11(a) to 11(c), the outer surface of the claw portion 59b is composed of an inclined outer surface 59c and an outer end face 59d parallel to the insertion direction Y of the cover 42. The inclined outer surface 59c is inclined so as to enter inward as it goes in the insertion direction Y of the cover 42. The inclined outer surface 59c is pushed by the open end face 51b outside the step portion side locking portion 51 formed on the step portion 50 when the cover 42 is inserted. Also, a hook corner portion 59e larger than 90 degrees and smaller than 180 degrees is provided between the inclined outer surface 59c and the outer end face 59d.

[0064] Similarly, as shown in FIG. 7, a cover-side locking hook portion 59 similar to that of the upper wall 55 is also formed at a corner portion 56c located on the side opposite to the side wall 57 among the corner portions 56b and 56c on the tip 56e side of the lower wall 56.

[0065] Also, as shown in FIG. 9, the height H of the stepped portion 50 along the thickness direction Z of the fuse body 3 is larger than the thicknesses T3 and T4 of the upper wall 55 and the lower wall 56 along the thickness direction Z of the fuse body 3. The thicknesses T3 and T4 have the same thickness. By making the height H of the stepped portion 50 larger than the thicknesses T3 and T4 of the upper wall 55 and the lower wall 56, the upper wall 55 and the lower wall 56 are prevented from detaching from the body 4 beyond the stepped portion 50.

[0066] Also, as shown in FIG. 9, in a state where the upper wall 55 and the lower wall 56 of the cover 42 are inserted into the pair of upper and lower stepped portions 50 of the fusant accommodating portion 43, the lower surface 55e of the upper wall 55 and the upper surface 56d of the lower wall 56 are in contact with the bottom surface 50a of each stepped portion 50. By this contact, the cover 42 is fixed to the body 4.

[0067] Next, with reference to FIGS. 8, 10, and 11, the insertion process of the cover 42 into the fusant accommodating portion 43 of the body 4 will be described.

[0068] First, the state on the side wall 57 side when the cover 42 is inserted will be described.

[0069] As shown in FIG. 10(a), the cover 42 is inserted along the insertion direction Y of the cover 42. Then, after the inclined portion 57b of the tip portion 57a of the side wall 57 is lifted along the inclined surface 52b of the protrusion 52, as shown in FIG. 10(b), it rides on the protrusion 52 of the tip portion 57a of the side wall 57. By riding on this protrusion 52, the side wall 57 elastically deforms in a direction away from the upper wall 55. Then, when the cover 42 is further inserted along the insertion direction Y of the cover 42, as shown in FIG. 10(c), the side wall 57 approaches the upper wall 55 and returns to the position before elastic deformation. At this time, as shown in FIG. 8, the protrusion 52 of the body 4 is located within the slot 58 of the side wall 57, and the cover-side locking portion 58a is locked to the body-side locking portion 52a.

[0070] Next, the state of the cover-side locking hook portion 59 when the cover 42 is inserted will be described.

[0071] As shown in FIG. 11(a), the cover 42 is inserted along the insertion direction Y of the cover 42. Then, as the cover 42 is further inserted, the opening end face 51b of the stepped portion-side locking portion 51 presses the inclined outer surface 59c inward, and after the cover-side locking hook portion 59 is elastically deformed so as to approach the upper wall 55, as shown in FIG. 11(b), the hook corner portion 59e rides on the opening end face 51b of the stepped portion-side locking portion 51. Then, as the cover 42 is further inserted, the cover-side locking hook portion 59 is locked to the stepped portion-side locking portion 51 with the portion including the inclined outer surface 59c and the outer end face 59d of the cover-side locking hook portion 59 disposed within the stepped portion-side locking portion 51.

[0072] In the second embodiment, the base wall portion 28, the pair of side wall portions 29, 30, and the reinforcing wall portion 31 of the soluble body accommodating portion 27 of the first embodiment are replaced with the base wall portion 44, the pair of side wall portions 45, 46, and the reinforcing wall portion 47 of the soluble body accommodating portion 43, and the insertion direction Y of the cover 42 is changed. Therefore, the basic configuration is the same as that of the first embodiment. Accordingly, the second embodiment has the effects of suppressing damage to the appearance of the body 4 and the cover 42 when the first soluble body 9 and the second soluble body |10| are melted, preventing incorrect assembly of the cover 42, reducing the types of parts of the high-current fuse, reducing the manufacturing cost of the high-current fuse, and fixing the cover 42 to the body 4.

[0073] Also, in the second embodiment, a cover-side locking hook portion 59 is formed at a corner portion 55c located on the side opposite to the side wall 57 among the two corner portions 55b and 55c on the tip 55a side of the upper wall 55. Further, a step-side locking portion 51 is formed at a position on the reinforcing wall portion 47 side among the portions corresponding to the inner side wall portion 46 of the step portion 50, and the step-side locking portion 51 is a concave portion in which the inner surface 50b of the step portion 50 is recessed outwardly in a rectangular shape. Then, the claw portion 59b of the cover-side locking hook portion 59 is locked to the step-side locking portion 51. By this locking, the cover 42 is fixed not only on the outer side wall portion 45 side but also on the inner side wall portion 46 side. Therefore, the detachment of the cover 42 from the soluble body accommodating portion 43 can be further suppressed.

Explanation of Signs

[0074] 3···Fuse body 4···Body 5···Cover 9···First soluble body 9a···Elongated portion 10···Second soluble body 27···Soluble body accommodating portion 28···Base wall portion 29···Side wall portion 30···Side wall portion 31···Reinforcing wall portion 34···Step portion 37···Base wall 38···Upper wall 39···Lower wall 40···Side wall 41a···Cover-side locking portion 42···Cover 43···Soluble body accommodating portion 44···Base wall portion 45···Side wall portion 46···Side wall portion 47···Reinforcing wall portion 54···Base wall 55···Upper wall 56···Lower wall 57···Side wall 58a···Cover-side locking portion 59···Cover-side locking hook portion

Claims

1. A fuse body electrically connected to a battery post of a battery via a power terminal and having a fusible element that melts due to overcurrent; A synthetic resin body integrally formed with the fuse body and having a fusible element accommodating portion that surrounds and accommodates the fusible element in a U-shape from three sides; A U-shaped synthetic resin cover inserted into the fusible element accommodating portion and closing the fusible element accommodating portion, and comprising: The cover further has side walls extending from side edges of the cover so as to cover an opening on a side of the cover; The side wall of the cover has a cover-side locking portion extending in a direction not coinciding with the insertion direction of the cover; The cover-side locking portion locks to a body-side locking portion provided on an outer surface of the fusible element accommodating portion. A high-current fuse for direct power supply, characterized by the above.

2. The fusible element accommodating portion is formed in a rectangular tube shape that surrounds and accommodates the fusible element in a rectangular shape from four sides, and has a base wall portion facing the insertion direction of the cover, a pair of side wall portions extending orthogonally to the base wall portion from both end portions of the base wall portion, and a reinforcing wall portion that connects the end portions on the side opposite to the base wall portion of the pair of side wall portions and reinforces the fusible element accommodating portion. The high-current fuse for direct power supply according to claim 1, characterized by the above.

3. The fuse body has a connection hole through which a stud bolt provided on the power terminal is inserted; The fusible element has a similar L shape and a pair of fusible elements arranged symmetrically with respect to the connection hole; The fusible element accommodating portion has a similar shape and a pair of fusible element accommodating portions arranged symmetrically to accommodate the pair of fusible elements respectively; The cover has a similar shape and closes the pair of fusible element accommodating portions respectively. The high-current fuse for direct power supply according to claim 1, characterized by the above.

4. The cover has a base wall parallel to the thickness direction of the fuse body, an upper wall extending orthogonally to the base wall from an upper edge portion of the base wall, a lower wall extending parallel to the upper wall from a lower edge portion of the base wall, and the side wall extending orthogonally to the base wall from a side edge of the base wall; At both end portions of the base wall portion and the pair of side wall portions in the thickness direction of the fuse body, a pair of stepped portions that are U-shaped and recessed stepwise from inner edges of the both end portions are formed, and the upper wall and the lower wall of the cover are respectively inserted into the pair of stepped portions. The depth of each of the pair of stepped portions along the thickness direction of the fuse body is greater than the thickness of the upper wall and the lower wall of the cover along the thickness direction of the fuse body. The high-current fuse for direct power supply according to claim 2, characterized in that.

5. The side wall of the cover has a rectangular slot extending from the side edge of the base wall to the vicinity of the tip of the side wall along the insertion direction of the cover, and the end face of the slot opposite to the side edge of the base wall becomes the cover-side locking portion orthogonal to the insertion direction of the cover. The fusible body accommodating portion has a protrusion protruding outward along a direction orthogonal to the insertion direction of the cover and the thickness direction of the fuse body from the outer surface of the fusible body accommodating portion, and the protrusion has a body-side locking portion to which the cover-side locking portion is locked. The high-current fuse for direct power supply according to claim 4, characterized in that.

6. The fusible body has an L shape including an elongated and continuous elongated portion extending in a direction orthogonal to the insertion direction of the cover and the thickness direction of the fuse body. The side wall of the cover has a rectangular slot extending from the side edge of the base wall to the vicinity of the tip of the side portion along the insertion direction of the cover, and the longitudinal end face of the slot opposite to the side edge of the base wall becomes the cover-side locking portion orthogonal to the insertion direction of the cover and the thickness direction of the fuse body. The fusible body accommodating portion has a protrusion protruding in the longitudinal direction of the elongated portion from the outer surface of the fusible body accommodating portion, and the protrusion has a body-side locking portion to which the cover-side locking portion is locked. The high-current fuse for direct power supply according to claim 4, characterized in that.

7. At a portion adjacent to the inner side wall portion of the pair of side wall portions in each of the pair of stepped portions, a stepped portion-side locking portion, which is a recess opening toward the fusible body accommodating portion, is formed. Cover-side locking hook portions that lock to the stepped portion-side locking portions are respectively formed at the corners located on the side opposite to the side wall among the two corner portions on the tip side of the upper wall and the lower wall. The high-current fuse for direct power supply according to claim 6, characterized in that.

8. The cover is fixed to the body by the lower surface of the upper wall portion of the body and the upper surface of the lower wall portion abutting against the upper surface of the upper stepped portion and the lower surface of the lower stepped portion among the pair of stepped portions. The high-current fuse for direct power supply according to claim 4, characterized in that.

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