JPH0712300Y2 - Box waterproof structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a waterproof structure of a metal box for housing an operating mechanism and a control device used outdoors of a power switch, for example.

“Prior Art” FIG. 4 is an external view showing a state where the box body 1 and the lid 2 are fixed with bolts 3. An example of a conventional structure for waterproofing the box body 1 having such a combination will be described with reference to FIGS. 8 and 9.

In FIG. 8, the bolt 3 penetrates the inside of the box body 1 and
The nut member 4 is fixed to the inside by welding. A seal member 5 is interposed between the box body 1 and the lid 2, and the bolt 3 is tightened from the outside of the lid 2 via the seal member 6 so that the mating surface (a) of the box body 1 and the lid 2, the lid 2 Bolt 3 hole (b) on the top surface and bolt 3 neck (c)
It is configured to prevent inundation from the route of.

FIG. 9 is a structural example used for the purpose of further improving waterproofness as compared with FIG. 8, in which the nut member 14 is welded to the outer periphery of the box body 11 and the bolt 3 is penetrated into the box body 11. Instead, it is located on the outer periphery of the box body 1 to eliminate the inundation paths (b) and (c) shown in FIG.
The box 11 is constructed by welding so that 11 forms the U-shaped groove 7, and it is intended that rainwater or the like does not directly contact the sealing member 5 of the lid 12 joint.

"Problems to be solved by the invention" In the case of the structure shown in FIG. 8, there are many water infiltration paths, and when the lid 2 is removed or tightened, the seal member 6 at the neck portion of the bolt 3 is twisted and worn. Not only may it be damaged by scratches and impair the waterproofness, but rainwater or the like may directly touch the seal member 5 at the joint portion of the lid 2 from the path of (a), and
There was a case where the box body 1 was flooded due to the suction action accompanying the decrease in the internal pressure.

The structure shown in FIG. 9 has greatly improved this drawback, but it has drawbacks that it is difficult to obtain dimensional accuracy and the cost is high due to the large amount of welding used in the manufacturing method.

Further, in the structure shown in FIGS. 8 and 9, there is no means for controlling the compression margin of the seal member 5, so that not only the sealing performance is unstable but also the seal member 5 may be damaged by overtightening the bolt 3. there were.

"Means and Actions for Solving Problems" The present invention is intended to obtain a highly reliable waterproof structure of a box body at a low cost. A bolt tightening part is pressed from one plate by pressing. By molding and forming a box body corresponding to a conventional structure with minimum welding, and combining with a nut member, the compression margin of the seal member is regulated.

"Embodiment" Next, an embodiment of the present invention will be described with reference to FIGS.

The box body 21 is formed by pressing from a single plate to have a cross-sectional shape similar to that shown in FIG. 9, a U-shaped groove is provided at the front circumference of the opening of the box body, and an attachment for fixing the nut member 28 is provided. Hole 29
On the outer circumference of the box.

Only the portion shown by the thick line in FIG. 2 is welded.

The nut member 28 is provided with a bolt 23 and a female screw into which a bolt 30 for fixing the nut member 8 to the box body 21 is threadedly penetrated along the central axis of a cylindrical or quadrangular prism member.

The order of assembling is that the nut member 28 is fixed to the box body 21 by the bolt 30, and then the lid 22 is fixed by the bolt 23 through the seal member 5.
Install by.

As a result, similar to FIG. 9, high waterproof performance can be obtained, but since only the four corners shown by thick lines in FIG. 2 are welded and the others are obtained by press molding, the dimensional accuracy is high and the cost is low.

FIG. 5 is another embodiment showing the mounting state of the nut member,
The thickness of the plate forming the box body 21 is represented by t. The box body 21 is provided with a mounting hole 39 for the nut member 38.
Has a quadrangular shape with chamfered four corners as shown in FIG. As shown in FIG. 7, the nut member 38 fitted therein has a length l corresponding to the plate thickness t at the lower end of the square member shown in the figure.
The corners are processed to eliminate the corners, and when the mounting bolt 30 is turned as shown in FIG.

The overlapping portion 24 in FIG. 1 is in close contact with each other, and it has been confirmed by a salt spray test or the like that no corrosion occurs for a long time only by coating.

"Effect of Invention" According to the present invention, there are the following effects.

A box similar to the structure of FIG. 9 can be obtained from one plate, and the number of parts can be reduced. Further, since there are almost no welded portions, dimensional accuracy is easy to obtain and it is inexpensive. Further, since the compression allowance of the seal member 5 is constantly regulated by the nut member, there is no risk of damaging the seal member due to overtightening of the bolt 3, and conversely it is possible to check the insufficient tightening, so that the tightening torque and the like can be easily managed. Therefore, the reliability of waterproofing is improved, and the workability of tightening the lid is improved.

[Brief description of drawings]

1 is a view for explaining an embodiment of the present invention, FIG. 2 is a view showing a welded portion of a box body of the present invention, and FIG. 3 is a perspective view of a nut member to be assembled with the box body of the present invention, FIG. 4 is an external view of the entire structure including the box of the present invention. 5 to 7 are views for explaining another embodiment of the present invention, and FIGS. 8 and 9 are views showing a conventional structure example. In the figure, 21 is a box body 23 is a bolt 28, 38 is a nut member 29, 39 is a mounting hole.

Claims (2)

[Scope of utility model registration request] 1. A box body having an outer shape of a substantially rectangular parallelepiped or a cube, at least one of six faces of which is open, and a lid fixed to the open face by a seal member with a bolt, wherein the opening is formed. The front end of the box body on the surface side is bent inward, bent toward the opening surface, further folded back, and bent outward to form a U-shaped groove on the outside of the box body. The seal member is attached to the folded portion of the box body, and a mounting hole is provided on an upper side of the side of the box body forming the U-shaped groove, and an upper surface of the upper side. A nut member to which a bolt for fixing the lid is screwed is attached by a bolt penetrating the attachment hole in the U-shaped groove, and the lid covers the nut member and the upper side. Is formed, the length of the nut member, a bolt for fixing is screwed to the lid, when the lid is attached to the box body,
A waterproof structure for a box body, wherein the seal member is set so as to be regulated by an appropriate compression allowance. 2. The utility model registration claim, wherein the outer shape of the nut member and the mounting hole are formed in a square shape, and the tip end portion of the nut member is inserted into the mounting hole. The waterproof structure of the box described in 1).