JP2789072B2 - Nut for fusible link connection box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut for a fusible link connection box, and more particularly, to a versatility applicable to at least two types of fusible links having different external dimensions used for protection of a power supply circuit in a vehicle or the like. The present invention relates to a connection box nut having the same.

[0002]

2. Description of the Related Art Conventionally, there are fusible links used for vehicles such as automobiles, which have various external dimensions according to the rated current. In particular, fusible links for protecting electric circuits in automobiles are known. A plurality of types of rated currents are used for each unit, and their dimensions are different from each other. Therefore, at least two types of fusible link connection boxes to which lead wires for connecting the battery power supply and each electric device are attached are required.

As a conventional fusible link connection box, FIG. 5 shows a small connection box, and FIG. 7 shows a large connection box. The fusible links Ca and Cb are each formed of a substantially rectangular parallelepiped synthetic resin housing 110 containing a U-shaped fuse, and two mutually parallel conductive members connected to each end of the fuse and drooping from the housing 110, respectively. It comprises a leg 122 made of material and having a rib e bent inward at a right angle at the side edge, and a transparent cover 112 mounted on the housing 110. In the small fusible link Ca shown in FIG.
Is provided with an inverted U-shaped notch 123, and the connection box 103a
After engaging with the power supply or the electric device, the terminal A of the lead wire connected to the power supply or the electric device is superimposed thereon. Screw D secures and is electrically connected to central wall I.

As shown in FIG. 6 which is a longitudinal sectional view of FIG. 5, the connection box 103a is usually formed integrally with a top plate H and a central wall I hanging down the center of the back surface of the top plate. In addition, two recesses are defined on the upper surface of the top plate H by the peripheral wall F and the partition plate G so that two housings 110a of the fusible links Ca having the same outer dimensions are fitted, and the bottom surface thereof, that is, On the upper surface of the top plate H, two mutually parallel through holes E are formed symmetrically with respect to the center wall on both sides of the center wall I, and the two legs 122a can be inserted therethrough.

In the leg of the large fusible link Cb shown in FIG. 7, a round hole f corresponding to the boss b is formed in place of the notch 123 shown in FIG. Further, a rib e having both ends in the width direction bent inward at a right angle is formed on the leg 122b, and the height of the rib e is smaller than the width of the through hole E.

Next, a comparison is made between the small fusible link Ca and the large fusible link Cb having different capacities.
The distances Z ₁ and Z ₂ of the legs 122 of the book are the same width,
The space between two opposing through holes E of the connection box 103 is also the same width. The small fusible link Ca is connected to the connection box 10.
From the center of the boss portion b when mounted on 3a, the distance (effective leg length) P ₁ to the lower end of the housing 110a is effective leg length P ₂ is smaller than the large fusible link Cb. Further, the length X ₁ and width Y ₁ of the peripheral wall F junction box 103a for small fusible link Ca is less than the length X ₂ and width Y ₂ of the large fusible link Cb. That is,
The small fusible link Ca and the large fusible link Cb have dimensional differences such as P ₁ <P ₂ , X ₁ <X ₂ , and Y ₁ <Y ₂ .

In the conventional connection box 103 as described above,
The dimensional difference due to the difference in capacity of the fusible link to be fitted, that is, the peripheral wall dimension X, which matches the effective leg length P of the fusible link and the size of the housing 110,
Those having Y were used in each case. Therefore,
When installing multiple junction boxes in a narrow place on the vehicle body, a large installation space is required, and when installing a fusible link, the work may take time due to the difference in dimensions, and the insertion part may be damaged. In addition, there are various problems in terms of manufacturing costs due to mold molding.

In view of the above, the present applicant has proposed a fusible link junction box improved in view of the above problems. As shown in FIG. 8, two types of fusible links C having different rated currents are provided on the bottom 4 of the box 2.
A pair of common through-holes 5 for inserting the connection plates 122 of a and Cb are provided, and a lower surface of the bottom portion 4 has a central wall I located in the middle of the common through-holes 5 and both sides along the side surface 6 of the box body portion 2. Wall 3,
9 and a screw hole 9b and a pedestal 9a at the center between the side walls 3, 3 and the center wall I as shown in FIGS.
The connection box 1 is formed by inserting a terminal nut 9 made of

Further, the fusible link connecting plate 12 is connected to the terminal nut 9 having a fixed mounting position.
Effective leg P 2 is effective leg length P ₂ of large fusible link Cb is greater than the effective leg length P ₁ of small fusible link Ca as described above, to produce a difference h between them,
It is necessary to raise the bottom 4 of the large fusible link Cb by the difference h. Therefore, a step portion 14 is formed at a position higher by h from the bottom portion 4 of the inner inner peripheral wall 12 of the box portion 2 accommodating the housing 110a of the small fusible link Ca, and the housing of the large fusible link Cb is formed on the step portion 14. By mounting the lower end of the connection plate 110b and housing the housing 110b in the outer inner peripheral wall 13, the connection plate 12
The screw tightening position 2b matches the terminal nut 9.

The common through hole 5 has ribs e at both ends of a wide connecting plate 122b of the large fusible link Cb.
Holes 7 and 7 and small holes 8 and 8 for the rib e of the connection plate 122a having a narrow width of the fusible link Ca are formed. The through holes 7, 8 for the rib e of the connection plate 122 inserted through the common through hole 5 are provided on the side surfaces 10 of the side walls 3, 3 in which the terminal nut 9 is fitted by the pedestal 9a.
Are provided with two guide grooves 11a and 11b for guiding the rib e, and by tightening the inserted connection plate 122 into the screw hole 9b of the terminal nut 9 with the screw D via the terminal A of the lead wire, The electrical connection is completed.

[0011]

However, the improved junction box 1 has a structure in which a small fusible link Ca having a small rated current and a large fusible ring Cb having a large rated current can be shared. However, the terminal nut 9 is usually a small-diameter M6 nut (a screw name in JIS standard). Therefore, when the large fusible link Cb is used, a thick electric wire is used as the connection electric wire, and a large current flows, so that the fastening screw is loosened due to the heat generated at the connection portion, and the connection state is incomplete. Therefore, when using the large fusible link Cb, a tightening torque more than that required when tightening the small fusible link Ca is required, and a large-diameter M8 nut (JIS standard) is required to securely connect and prevent loosening. Nominal screw thread) must be used. In other words, the terminal nut 9 needs to be replaced each time according to the type of fusible link to be used, and despite the versatility of the connection box 1, a remarkable result in terms of work efficiency in assembly. Could not get.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above-mentioned conventional problems, and has as its object to improve the working efficiency by using a terminal nut which can be used for fastening different types of fusible links. .

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to form a pair of shared through holes for inserting at least two types of fusible links having different rated currents into a connecting plate having ribs at both end edges in the width direction of the box. At the bottom, a central wall located between the pair of shared through holes and both side walls along the side of the box body portion are vertically provided on the bottom lower surface, and a terminal is provided between the both side walls and the central wall. A nut for a fusible link connection box comprising a nut, wherein a small size is provided on the terminal nut according to different rib intervals of the connection plate of the fusible link.
Recess that can be fitted with ribs on the connecting plate of the fusible link
It is achieved by the fusible link connection box nut, characterized in that is provided. Further, the above object of the present invention is achieved by the fact that the recess is a slit.

[0014]

In the nut for the fusible link connection box of the present invention, when the connection plate having the ribs of the small fusible link is inserted from the common through hole, the ribs of the connection plate of the fusible link are placed on the terminal nut. Since the terminal nut is inserted into the provided slit, it is not necessary to replace the terminal nut, and furthermore, it is possible to securely connect and prevent loosening of the screw due to heat generation at the connection portion.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a fusible link connection box nut according to the present invention will be described below with reference to FIGS. 1 is a perspective view of a connection box for a fusible link according to the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, FIG. 3 is a plan view of a nut for a connection box according to the present invention, and FIG. It is BB sectional drawing. Since the connection box except for the fusible link and the terminal nut is the same as the conventional example, the same reference numerals as those in the conventional example are given, and the overlapping detailed description will be omitted.

As shown in FIGS. 1 and 2, the terminal nut 15 is provided with a small-diameter female screw hole 15a that penetrates and a large-diameter female screw hole 15b that does not penetrate, and a pair of parallel slits 15c. Is provided.
The pedestal 15 d of the terminal nut 15 has a predetermined thickness d and is formed between the above-described central wall I formed on the connection box 1 and the nut mounting rib 3 a provided inside the side wall 3. The terminal nut 15 is attached to the connection box by being press-fitted from the lower end. This terminal nut 15
Is fixed to a fixed position by the terminal nut 15 abutting on the locking portion 1a of the connection box 1.

As described above, the effective leg length P ₂ of the connection plate 122b of the large fusible link Cb (see FIG. 7).
Is the effective leg length P ₁ of the small fusible link Ca (FIG. 5)
See) longer, by the difference h is to place the lower end of the housing 110b on the stepped portion 14, the connection plate 122b
The upper round hole f is positioned at a position where the terminal nut 15 is mounted. Therefore, the fastening positions of the connection plates of both fusible links also match the upper end surface of the terminal nut 15.

When the small fusible link Ca is inserted, the connection plate 122a of the small fusible link Ca is inserted into the through hole 8 of the connection box 1 from above until the lower end of the housing 110a comes into contact with the bottom 4 so that the connection is established. The side end rib e (see FIG. 5) of the plate 122a is inserted into the slit 15c of the terminal nut 15 from the guide groove 11a and positioned. Then, the small fusible link Ca can be tightened and fixed together with the connection terminal by placing the connection terminal on the connection plate 122a and then screwing the M6 screw into the female screw hole 15a.

When the large fusible link Cb is inserted, the connection plate 12 of the large fusible link Cb is used.
2b (see FIG. 7) is inserted through the through-hole 7, the connection plate 12
The side end rib 2b of the housing 2b is inserted into the guide groove 11b.
The round hole f on 2b is the female screw hole 15 of the terminal nut 15.
It is positioned at a position matching b. And the connection plate 1
You can tightened to fix the large-fusible link Cb together with the connection terminal by screwing after held against the connecting terminal on the 22b to M8 screw into the female screw hole 15b.

As shown in FIGS. 3 and 4, the terminal nut 15 according to the present invention is formed as a double nut in which a small-diameter female screw hole 15a and a large-diameter female screw hole 15b are provided concentrically. The terminal nut 15 has a rib e of the connection plate 122a of the small fusible link Ca (see FIG. 5).
Is provided, and the connection plate 122a can be brought into contact with the upper end surface of the terminal nut 15. The rib e (see FIG. 7) of the connection plate 122b of the large fusible link Cb is provided in the guide groove 11b (see FIG. 1 ) located outside the terminal nut 15 .
)) . In this embodiment, when fixing the small fusible link Ca for small capacity to the connection box 1,
The M6 screw is tightened to the small-diameter female screw hole 15a with a predetermined torque via the connection plate 122a and the connection terminal. When fixing the large-sized fusible link Cb for large capacity, the M8 screw is tightened to the large-diameter female screw hole 15b with a predetermined torque via the connection plate 122b and the connection terminal.

[0021]

As described above, according to the present invention, according to the different rib intervals of the connecting plate of the fusible link,
The required small fusible link is placed on the terminal nut.
Providing a concave part in which the ribs of the connection plate can be inserted makes it necessary to select and install a dedicated terminal nut when installing one of at least two types of fusible links with different rated currents into the connection box. And efficient assembly work is possible. In addition, even if you replace the other types of fusible link, rather than need to replace the terminal nut, yet equipped with a small fusible link
The connection and prevent the screws from loosening.
I can . Therefore, the workability can be greatly improved because one terminal nut can be used in common, and the cost can be reduced by halving the parts management.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fusible link connection box showing an embodiment according to the present invention.

FIG. 2 is an AA vertical cross-sectional view when a fusible link is mounted on the connection box of FIG. 1;

FIG. 3 is a plan view of a terminal nut according to an embodiment of the present invention.

FIG. 4 is a sectional view taken along line BB in FIG. 3;

FIG. 5 is a perspective view of a conventional small-capacity fusible link connection box.

FIG. 6 is a sectional view taken along line NN in FIG. 5;

FIG. 7 is a perspective view of a conventional large-capacity fusible link connection box.

FIG. 8 is a perspective view of a fusible link connection box in a second conventional example.

FIG. 9 is a plan view of a conventional terminal nut.

FIG. 10 is a sectional view of FIG. 9;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Connection box 1a Locking part 2 Box body part 3 Side wall 3a Rib 4 Bottom part 5 Common through hole 6 Box body part side surface 7 Rib through hole 8 Rib through hole 11a Groove 11b Groove 12 Inner inner peripheral wall 13 Outer inner peripheral wall 14 step Part 15 Terminal nut 15a Small diameter screw hole 15b Large diameter screw hole 15c Slit (recess) 15d Base Ca Small capacity fusible link for small capacity Cb Large fusible link for large capacity h Step I Central wall P ₁ Small fusible link connection plate valid leg 122 connecting plate of the active leg P ₂ large fusible link connection plate

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01H 85/56

Claims (2)

(57) [Claims] 1. A pair of common through holes for inserting connection plates having ribs at both ends in the width direction of at least two types of fusible links having different rated currents are provided at the bottom of the box body portion, and at the bottom surface of the bottom portion. A fusible link connection comprising a central wall located in the middle of the pair of shared through-holes and side walls along the side of the box body, and a terminal nut between the side walls and the central wall. In the box nut, a small fusible ring is provided on the terminal nut according to different rib intervals of the connecting plate of the fusible link.
A fusible link connection box nut provided with a concave portion into which a rib of a connection plate of the hook can be inserted . 2. The nut for a fusible link connection box according to claim 1, wherein the recess is a slit.