JP2013070561A - Electric connection box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric connection box having a new structure including a spare fuse housing part which stably houses and holds both a low height fuse and a mini fuse.SOLUTION: In a spare fuse housing part 14, retractable support parts 42 which contact with insertion side tip surfaces 60, 66 of fuse bodies 56, 64 in fuses 50, 52 and expand and retract in the fuse insertion direction and an engagement part 22 engaging with insertion side rear end surfaces 68, 70 of the fuse bodies 56, 64 are provided.

Description

  The present invention relates to an electrical junction box, and more particularly to an electrical junction box provided with a spare fuse accommodating portion for accommodating a spare fuse.

  As is well known, an electrical junction box such as a junction box provided in an automobile has a large number of fuses. When an overcurrent is passed through the electric circuit, the fuse is blown to cut off the overcurrent, thereby protecting the electric circuit.

  By the way, it is necessary to replace the blown fuse with a new fuse. In order to facilitate this replacement, some of the electrical connection boxes are provided with a spare fuse accommodating portion for inserting and accommodating a spare fuse for replacement in advance in the upper case or the box body.

  However, at present, two types of fuses are widely used. One is a so-called low profile fuse having a small height dimension in which a pair of connection terminals are exposed from notches on both the left and right sides of the fuse body. A spare fuse accommodating portion for such a low profile fuse is disclosed in Japanese Patent Laid-Open No. 2007-28763 (Patent Document 1). The other is a so-called mini fuse having a large height, in which a pair of connection terminals protrudes from the fuse body. Japanese Patent Application Laid-Open No. 9-245611 (Patent Document 2) discloses a spare fuse housing portion for such a mini fuse.

  Since these low-profile fuses and mini-fuses have different shapes, the spare fuse accommodating portions have different shapes. Therefore, when both a low-profile fuse and a mini-fuse are used in a single electrical junction box, a spare fuse housing corresponding to each of the low-profile fuse and mini-fuse must be provided separately. There were problems that the space efficiency in the junction box was reduced and the manufacturing cost was increased.

JP 2007-28763 A Japanese Patent Laid-Open No. 9-245611

  The present invention has been made in the background of the above-mentioned circumstances, and the problem to be solved is that it can be used in common for so-called low-profile fuses and mini-fuses. It is an object of the present invention to provide an electrical junction box having a novel structure provided with a spare fuse accommodating portion that can be stably accommodated and held.

  According to a first aspect of the present invention, in the electrical junction box including a spare fuse housing portion for inserting and housing a spare fuse, the spare fuse housing portion is in contact with the insertion-side front end surface of the fuse body in the fuse. Thus, there is provided a telescopic support portion that can be expanded and contracted in the fuse insertion direction, and a locking portion that locks the rear end surface on the insertion side of the fuse body.

  According to the electrical junction box having the structure according to the present invention, the main body portion of the fuse inserted into the spare fuse accommodating portion can be held between the telescopic support portion and the locking portion. The spare fuse housing is provided with a telescopic support that can be shrunk in the fuse insertion direction, and in the case of a low profile fuse with a relatively small height in the fuse insertion direction, The universal support portion hardly contracts and can be stably held with the main body portion of the low-profile fuse sandwiched between the spacer and the locking portion. On the other hand, in the case of a mini fuse having a relatively large height in the main body part in the fuse insertion direction, the telescopic support part contracts in the fuse insertion direction, so that the mini A housing space corresponding to the size of the fuse body of the fuse can be formed, and the body portion of the mini-fuse can be stably held between the extendable support portion and the locking portion. That is, the retractable support portion contracts according to the size of the main body portion of the fuse to be inserted (height in the fuse insertion direction), so that the accommodation space between the extendable support portion and the locking portion is large. The size can be automatically adjusted to a size corresponding to the size of the main body portion of the fuse to be inserted. As a result, both the low profile fuse and the mini fuse can be inserted into the spare fuse accommodating section, and both the low profile fuse and the mini fuse can be stably accommodated and held. As a result, even when both a low-profile fuse and a mini-fuse are used, it is not necessary to form a spare fuse housing for each fuse, so that better space efficiency can be obtained and the manufacturing cost can be reduced. Can be planned. Further, since it is not necessary for the operator to distinguish between the low-profile fuse and the mini-fuse and accommodate them in the spare fuse accommodating portion, it is possible to improve the efficiency of the assembly work.

  The telescopic support portion may be any member that contracts due to the pressing force in the fuse insertion direction and becomes smaller in the fuse insertion direction, but elastically returns to the original size when the pressing force is released. . Therefore, the extendable support portion may be a thin wall that can be tilted in the fuse insertion direction by a resin material, such as a rubber elastic body or a spring member, and may be compressed and deformed to reduce the dimension in the fuse insertion direction. It is also possible to provide a plate portion or the like of which the size is reduced in the fuse insertion direction by tilting the plate portion. Further, the telescopic support portion may be in direct contact with the fuse body, or may be in indirect contact with another member or the like. In addition, the retractable support part shrunk by the insertion of the fuse is restored by the elastic restoring force, so that the fuse body is urged toward the locking part side so that the fuse body is more stable with the locking part. Can be held.

  According to a second aspect of the present invention, there is provided the first aspect according to the first aspect, wherein the stretchable support portion is formed into a plate shape that can be bent and deformed in a fuse insertion direction, and is integrally molded with the preliminary fuse housing portion. It is what has been.

  According to this aspect, it is possible to manufacture cost-effectively by integrally molding the telescopic support portion into the preliminary fuse housing portion by resin molding. In particular, since the stretchable support portion is capable of being bent and deformed in the fuse insertion direction, some bending deformation is allowed even in the fuse removal direction, which is the mold release direction of the mold during resin molding. Even when the molding cavity of the stretchable support portion is configured by the molding die, the so-called forcing can be removed without being caught by the stretchable support portion by bending and deforming the stretchable support portion at the time of die cutting. As a result, the divided structure of the mold can be simplified, and the manufacturing cost can be further reduced.

  A third aspect of the present invention is the one described in the second aspect, wherein the telescopic support portion has a curved plate shape extending in an arc shape in the fuse insertion direction.

  According to this aspect, local stress concentration in the extendable support portion is avoided, and the possibility of damage to the extendable support portion is reduced, and the fuse body is more stably biased toward the locking portion side. I can do it. In addition, since the local stress concentration in the stretchable support portion is avoided when the spare fuse accommodating portion is molded during resin molding, the possibility of damage to the stretchable support portion during the so-called forced removal is reduced. You can also

  In the present invention, the auxiliary fuse accommodating portion is brought into contact with the front end surface of the fuse body on the insertion side so as to be extendable in the fuse insertion direction, and the latch for locking the insertion side rear end surface of the fuse body. And set up part. As a result, the telescopic support portion contracts in accordance with the size of the fuse body to be inserted, so that the fuse body has a relatively small size and a so-called low profile fuse and the fuse body has a relatively large size. Any of the so-called mini fuses can be inserted, and the fuse body can be stably held between the extendable support portion and the locking portion. As a result, the spare fuse accommodating portion can be used in common for both the low-profile fuse and the mini-fuse, so that more excellent space efficiency can be obtained and the manufacturing cost can be reduced.

The perspective view of the upper case which comprises the electrical junction box as one Embodiment of this invention. The perspective view of a reserve fuse accommodating part. FIG. 3 is a plan view of a spare fuse accommodating portion shown in FIG. 2. IV-IV sectional drawing in FIG. VV sectional drawing in FIG. The principal part enlarged view in FIG. Cross-sectional explanatory drawing for demonstrating the manufacturing method of a telescopic support part. The front view of a low profile fuse. The front view of a mini fuse. Sectional drawing corresponding to FIG. 4 which shows the accommodation state of a low profile fuse. Sectional drawing corresponding to FIG. 4 which shows the accommodation state of a mini fuse.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, FIG. 1 shows an upper case 10 constituting an electrical junction box as one embodiment of the present invention. The upper case 10 is an integrally molded product made of a synthetic resin, and is assembled by being put on an upper portion of a box body (not shown) to which electrical parts such as a fuse and a relay are connected, as is conventionally known.

  A spare fuse accommodating portion 14 is integrally formed on the inner surface 12 of the upper case 10. The spare fuse accommodating portion 14 is formed in a region where the height of the electrical component to be mounted on the box body in the upper case 10 is low, so that the spare fuse accommodating portion 14 does not interfere with the electrical component. As shown in FIGS. 2 to 5, in this embodiment, three spare fuse accommodating portions 14 are formed in parallel.

  The spare fuse accommodating portions 14 have substantially the same shape. As is apparent from FIG. 3, the spare fuse accommodating portion 14 has a pair of U-shaped side walls 16a and 16b projecting from the inner surface 12 with a predetermined gap therebetween. A tapered surface 20 that is inclined toward the inner surface 12 is formed at the upper end (the upper end in FIG. 4) of the central long side portion 18 in each of the side walls 16a and 16b. A protrusion-like locking portion 22 that slightly protrudes in the opposing direction of 16a and 16b is formed. Further, reinforcing ribs 24 having a substantially triangular cross-section are formed at the lower ends (lower ends in FIG. 4) of the long side portions 18 of the side walls 16a and 16b so as to protrude outward in the opposing direction of the side walls 16a and 16b and to be connected to the inner surface 12. Has been. In the present embodiment, since the three spare fuse accommodating portions 14 are formed in parallel, the three sidewalls 16a and 16b of each spare fuse accommodating portion 14 are connected and formed integrally. Yes.

  As shown in FIG. 5, a pair of side walls 16a and 16b has a pair of left and right ends 26a and 26b at the front ends facing inward (left and right directions in FIG. 5) in the opposite direction of the left and right ends 26a and 26b, respectively. The sandwiching pieces 28, 28 protrude, and a slit 30 extending in the fuse insertion direction (vertical direction in FIG. 5) is formed between the sandwiching pieces 28, 28. Further, a tapered surface 32 that is inclined toward the inner surface 12 is formed at the upper end (the upper end in FIG. 5) of the sandwiching piece 28 that forms the inner surface of the slit 30, and connection terminals 54 of fuses 50 and 52 described later. 62 are easily inserted. Note that, between the adjacent pair of spare fuse accommodating portions 14, 14, a sandwiching piece 28 at the right end portion 26 a of one spare fuse accommodating portion 14 and a sandwiching piece 28 at the left end portion 26 b of the other spare fuse accommodating portion 14 are Connected and formed integrally.

  Further, a stopper portion 34 protruding from the inner surface 12 is formed at the center of the opposing side walls 16a, 16b. As apparent from FIG. 3, the stopper portion 34 has a pair of end wall portions 36, 36 that face each other in the facing direction of the side walls 16 a, 16 b, and are connected by a central wall portion 38 that extends in the facing direction of the side walls 16 a, 16 b. In a plan view (see FIG. 3), it has a substantially H shape and is formed to protrude from the inner surface 12 in the same direction as the side walls 16a and 16b (upward in FIG. 5).

  As shown in FIG. 6, a pair of telescopic support portions 42 and 42 are integrally formed on the upper surface 40 of the stopper portion 34. The telescopic support portions 42 and 42 have a plate shape protruding upward (upward in FIG. 6) from the end portion on the central wall 38 side of the upper surface 40 of the both end wall portions 36 and 36. In the present embodiment, the telescopic support portions 42 and 42 have arcuate shapes that curve so as to spread on both outer sides (left and right sides in FIG. 6) in the opposing direction of the end wall portions 36 and 36 (left and right directions in FIG. 6). It is made into the plate shape which protrudes and extends upwards. Accordingly, the telescopic support portions 42 and 42 can be deformed downward (downward in FIG. 6) when the fuses 50 and 52 are inserted and pressed by the fuse bodies 56 and 64 as will be described later. In the vertical direction (vertical direction in FIG. 6), which is the fuse insertion direction, the protruding height dimension HL from the upper surface 40 can be shrunk to HL ′. The telescopic support portions 42 and 42 are leaf springs that can be restored to their original shape by elastic restoring force when the downward pressing force is released. As shown in FIG. 6, tapered surfaces 43 and 43 that are inclined toward the inner surface 12 are formed on the outer surfaces of the stopper portions 40 on the upper surfaces 40 of the end wall portions 36 and 36, respectively. The connection terminals 62 and 62 of the fuse 52 can be easily inserted.

  As shown in FIG. 7, the stretchable support portions 42 and 42 in the present embodiment can be resin-molded with a single mold 44 that forms the stopper portion 34. Molding cavities 46 and 46 corresponding to the shape of the telescopic support portions 42 and 42 are formed in the molding die 44. The stretchable support portions 42 and 42 are integrally formed with the stopper portion 34 by injecting a resin material into the molding cavities 46 and 46 and curing the resin material. Then, as shown by an arrow in FIG. 7, the mold 44 is die-cut upward in the drawing, which is a direction in which fuses 50 and 52 described later are removed. As described above, since the telescopic support portions 42 and 42 can be bent and deformed, they extend in a direction (left and right direction in FIG. 7) orthogonal to the die cutting direction (upward in FIG. 7). Even in the shape, as shown in FIG. 7, the mold 44 can be forcibly removed by bending and deforming the stretchable support portions 42, 42. Accordingly, the stretchable support portions 42 and 42 can be formed by the single mold 44, and the divided structure of the mold can be simplified and formed at low cost.

  In the spare fuse accommodating portion 14 having such a structure, the low profile fuse 50 shown in FIG. 8 and the mini fuse 52 shown in FIG. 9 can be accommodated in common. As shown in FIG. 8, the low-profile fuse 50 has a structure in which a fuse element provided with a not-shown fusing part between a pair of connection terminals 54, 54 is embedded in a resin fuse body 56. Has been. Notches 58 and 58 are formed on both the left and right sides of the fuse body 56 (left and right in FIG. 8), and the connection terminals 54 and 54 are exposed from the notches 58 and 58. Is a substantially rectangular block shape. Accordingly, the connection terminals 54 and 54 slightly protrude from the lower end 60 of the fuse body 56 in the low profile fuse 50.

  On the other hand, as shown in FIG. 9, the mini fuse 52 has a structure in which a fuse element provided with a not-shown fusing part is embedded in a resin fuse main body 64 between a pair of connection terminals 62 and 62. It is said that. The fuse body 64 has a substantially rectangular block shape, and the connection terminals 62 and 62 protrude from the lower end 66 of the fuse body 64, whereby the mini fuse 52 has a substantially gate shape when viewed from the front (see FIG. 9). ing.

  These low-profile fuse 50 and mini-fuse 52 have substantially the same lateral dimensions W1 and W2. On the other hand, the height dimension from the upper end 68 to the lower end 60 of the fuse body 56 in the low-profile fuse 50 is higher than the height dimension H1 from the upper end 70 to the lower end 66 of the fuse body 64 in the mini fuse 52. Has been increased. Further, the projecting dimension of the connection terminals 62 and 62 of the mini fuse 52 from the lower end 66 of the fuse body 64 is smaller than the projecting amount D1 of the connection terminals 54 and 54 of the low profile fuse 50 from the lower end 60 of the fuse body 56. : D2 is larger. That is, the height dimension of the mini fuse 52: H2 + D2 is made larger than the height dimension of the low-profile fuse 50: H1 + D1.

  Such a low-profile fuse 50 and a mini-fuse 52 can be accommodated by being inserted into the spare fuse accommodating portion 14. The low-profile fuse 50 and the mini-fuse 52 are inserted into the spare fuse accommodating portion 14 with the connection terminals 54, 54 or 62, 62 inserted through the slits 30, 30 of the spare fuse accommodating portion 14, respectively.

  As shown in FIG. 4, in the natural state where no pressing force or the like is applied to the telescopic support portions 42, 42, the fuse insertion direction between the telescopic support portions 42, 42 and the locking portions 22, 22 ( In FIG. 4, the separation distance (Hn in the vertical direction) is set to be substantially equal to or slightly smaller than the height dimension H1 of the fuse body 56 of the low-profile fuse 50. It is set small. Thus, as shown in FIG. 10, when the low-profile fuse 50 is inserted into the spare fuse accommodating portion 14, the lower end 60 of the fuse body 56 serving as the insertion-side front end surface contacts the telescopic support portions 42, 42. Then, the telescopic support portions 42 and 42 are slightly pressed and bent in the fuse insertion direction (downward in FIG. 10). Then, the lower end 60 is telescopically supported while the fuse body 56 of the low-profile fuse 50 is exerted with a slight biasing force on the locking portions 22 and 22 side by the elastic restoring force of the telescopic support portions 42 and 42. The upper end 68 that is supported by the portions 42 and 42 and is the rear end surface of the insertion side is locked by the locking portions 22 and 22, and is held between the telescopic support portions 42 and 42 and the locking portions 22 and 22. The

  On the other hand, as shown in FIG. 11, when the mini fuse 52 is inserted into the spare fuse accommodating portion 14, the height dimension H2 of the fuse body 64 of the mini fuse 52 is the height dimension of the fuse body 56 of the low profile fuse 50. When the height dimension: H1 is larger than H1, the lower end 66 of the fuse body 64 serving as the distal end surface on the insertion side comes into contact with the extendable support portions 42, 42, and the extendable support portions 42, 42 are the low-profile fuse 50. It is pushed and deflected to a greater extent in the fuse insertion direction (downward in FIG. 11). As a result, a space that can accommodate the fuse body 64 of the mini-fuse 52 is formed between the telescopic support portions 42 and 42 and the locking portions 22 and 22, and the fuse body 64 is accommodated. The lower end 66 is supported by the telescopic support portions 42 and 42 in a state where the biasing force is exerted on the locking portion 22 side by the elastic restoring force of the telescopic support portions 42 and 42. At the same time, the upper end 70 serving as the insertion-side rear end surface is locked to the locking portions 22, 22 and is held between the telescopic support portions 42, 42 and the locking portions 22, 22.

  As described above, in the upper case 10 having the structure according to the present embodiment, the spare fuse accommodating portion 14 can be expanded and contracted in the insertion direction of the fuses 50 and 52 (downward in FIGS. 10 and 11). Support portions 42 are formed. As a result, regardless of whether the low-profile fuse 50 or the mini-fuse 52 is inserted into the spare fuse accommodating portion 14, the telescopic support portions 42, 42 are connected to the fuse body 56 of the low-profile fuse 50 and the fuse body 64 of the mini-fuse 52. Height dimension: By bending and deforming in the fuse insertion direction by an amount corresponding to H1 and H2, the distance between the telescopic support portions 42 and 42 and the locking portions 22 and 22 is set to the height of the fuse bodies 56 and 64. The fuse body 56 of the low-profile fuse 50 and the fuse body 64 of the mini-fuse 52 can be accommodated in the spare fuse accommodating portion 14, and the telescopic support portions 42, 42 It can be stably held between the locking portions 22 and 22.

  When the telescopic support portions 42 and 42 are plate springs, when the fuse body 64 of the mini fuse 52 is inserted and the telescopic support portions 42 and 42 are bent and deformed in the fuse insertion direction, The fuse body 64 can be urged toward the locking portions 22 and 22 by the elastic restoring force. Thereby, the fuse main body 64 can be clamped between the telescopic support portions 42 and 42 and the locking portions 22 and 22 without any gap, and the mini fuse 52 can be held more reliably and stably. In particular, in the present embodiment, since the telescopic support portions 42 and 42 are slightly bent and deformed in the fuse insertion direction even when the low-profile fuse 50 is inserted, the fuse body of the low-profile fuse 50. 56 can be held more reliably and stably in a state of being biased toward the locking portions 22 and 22.

  Further, the telescopic support portions 42 and 42 are integrally formed with the upper case 10. Therefore, the spare fuse accommodating portion 14 that can be shared by the low profile fuse 50 and the mini fuse 52 can be formed at low cost without causing an increase in the number of components. Further, since the telescopic support portions 42 and 42 have an arc shape, it is possible to exert a stable elastic restoring force, and even when the fuses 50 and 52 are inserted and bent and deformed, Local stress concentration can be avoided, and the possibility of damage to the stretchable support portions 42 and 42 can be reduced.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, in the above-described embodiment, the two leaf spring-shaped stretchable support portions 42 and 42 are formed. However, the stretchable support portion may be formed with a single leaf spring shape, or the stretchable support portion may be stretched. The support portion may have a substantially flat plate spring shape that linearly protrudes obliquely from the upper surface 40 of the stopper portion 34. Further, the telescopic support portion is not necessarily formed integrally with the upper case 10. For example, a rubber elastic body separate from the upper case 10, a metal coil spring, or the like is provided on the upper surface 40 of the stopper portion 34. The retractable support portion may be formed so as to be contractible in the fuse insertion direction and exhibit an elastic restoring force while being compressed when the fuses 50 and 52 are inserted.

  In the above embodiment, the fuse bodies 56 and 64 are biased toward the locking portions 22 and 22 by the elastic restoring force of the telescopic support portions 42 and 42 in both cases of the low-profile fuse 50 and the mini-fuse 52. However, it is not limited to this. For example, when the low-profile fuse 50 with a small height is inserted, the telescopic support portions 42 and 42 are not contracted, and the lower end 60 of the fuse body 56 of the low-profile fuse 50 is simply the telescopic support portion. Of course, the present invention also includes a configuration in which the abutment is supported by 42 and 42.

  In addition, the stretchable support portion is not necessarily limited to the one that is directly in contact with the fuse bodies 56 and 64, and is, for example, stretchable support at an intermediate portion between the upper surface 40 and the inner surface 12 in the stopper portion 34. A portion may be provided, and the upper and lower surfaces 40 may be brought into contact with the fuse bodies 56 and 64 so that the telescopic support portion is in contact with the fuse bodies 56 and 64 indirectly.

  In the above embodiment, the locking portions 22 and 22 for locking the upper ends 68 and 70 of the fuse bodies 56 and 64 are formed integrally with the upper case 10, but for example, the upper case 10 is covered as the locking portion. The protrusions projecting from the box body side to the upper case 10 side are provided, and the upper ends 68 and 70 of the fuse bodies 56 and 64 are locked by the protrusions to hold the fuse bodies 56 and 64 between the telescopic support portions. You may make it do. Furthermore, it is of course possible to form the spare fuse accommodating part on the box body side.

10: Upper case (electric connection box), 14: Spare fuse accommodating part, 16a, b: Side wall, 22: Locking part, 34: Stopper part, 40: Upper surface, 42: Telescopic support part, 44: Mold, 50: Low profile fuse, 52: Mini fuse, 54, 62: Connection terminal, 56, 64: Fuse body, 60, 66: Lower end (insertion side front end surface), 68, 70: Upper end (insertion side rear end surface)

Claims (3)

In the electrical junction box provided with a spare fuse accommodating portion for inserting and accommodating a spare fuse,
In the spare fuse housing part,
An expandable support portion that is in contact with the insertion-side end surface of the fuse body in the fuse and is extendable in the fuse insertion direction;
An electrical connection box provided with a locking portion for locking the rear end surface on the insertion side of the fuse body. The electrical junction box according to claim 1, wherein the extendable support portion is formed into a plate shape that can be bent and deformed in a fuse insertion direction and is integrally molded with the spare fuse accommodating portion.   The electrical junction box according to claim 2, wherein the stretchable support portion has a curved plate shape extending in an arc shape in the fuse insertion direction.

Images