JPH0742169Y2 - Closed switchboard box - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) [0001] The present invention relates to a switchboard, and more particularly to a box body of a closed switchboard in which an exhaust port is provided at an intermediate portion of a ceiling.

(Prior Art) In FIG. 3 showing a perspective view of an example of a box body of a conventional closed switchboard and FIG. 4 showing an enlarged view of the AA cross section thereof, on the left side of the box body 1, there is an intake port 3a at the bottom. The front door 3 provided with is attached. Four reinforcing plates 41 having an L-shaped cross section are fixed by welding to the lower surface around a substantially square opening 40 formed in the center of the ceiling plate 2 in the upper part of the box body 1. A net plate 42 having an L-shaped cross section, which is provided with four drip-proof frames on the upper surface, is attached to the.

Above the net plate 42, a drip-proof plate 44 having an inverted U-shaped cross section is attached to the outside of the drip-proof frame 43 by a leg portion 44a vertically provided on the lower side of the center of each side. . Between the drip-proof plate 44 and the lower drip-proof frame 43 is an exhaust port 44b for discharging a space warmed by the heat of a circuit breaker (not shown) housed inside the box 1.

(Problems to be solved by the invention) However, in the box body of the closed switchboard configured as described above, the weight of the net plate 42 and the drip-proof plate 44 and the ceiling plate 2 at the time of maintenance and inspection are used.
The ceiling plate 2 is bent downward as shown by the broken line in FIG. 5 due to the weight of the maintenance personnel who went up to the upper part of the box, and as a result, as shown in FIG. Therefore, the flow of air discharged to the outside through the exhaust port 44b becomes poor.

Therefore, an object of the present invention is to obtain a box body of a closed switchboard which can be easily manufactured and can improve the flow of air exhausted from the ceiling of the box body.

(Means and Actions for Solving the Problem) The present invention is directed to a pair of first ceiling plates, which are rectangular and whose opposite sides are bent in an L shape on one side and the other side of a ceiling portion of a box having an open upper surface. A pair of second ceiling plates, each of which has a rectangular shape with three sides bent in an L shape, are symmetrically attached, and the periphery is bent into an L shape between the second ceiling plate and the first ceiling plate. By attaching a rectangular net plate and fixing these bent portions to each other, the bending of the ceiling plate is prevented, and the box body of the closed switchboard is easy to manufacture and allows smooth air discharge.

(Embodiment) An embodiment of a box body of a closed switchboard according to the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 1 is an exploded perspective view showing a box body of a closed switchboard of the present invention, and FIG. 2 is an exploded enlarged perspective view showing only the ceiling plate of FIG.

In FIGS. 1 and 2, on the upper side of the box body 11, one side of the long side of the rectangular mild steel plate is bent into an L-shape and a fastening portion is formed.
Left ceiling plate 22A and right ceiling plate 22B having the same shape and forming 22a and 22b.
Are installed facing each other with a space in between. Between these, the three sides are bent into an L shape and the fastening parts 21a, 21b, 21c
Similarly, a front ceiling plate 21A and a rear ceiling plate 21B, which have the same shape and in which the fastening portions 21d, 21e, and 21f are formed, are attached to face each other with a gap. The fastening portions 21a, 21c, 21d, 22f of the front ceiling plate 21A and the rear ceiling plate 21B are respectively overlapped with the fastening portions 22a, 22b and fastened with bolts.

Also, these left ceiling plate 22A, right ceiling plate 22B, front ceiling plate 21A,
In the substantially square opening formed between the rear ceiling plate 21B,
A net plate 23 having a substantially square shape in which four sides are bent downward to form a fastening portion is fixed to each fastening portion 21b, 21e, 22a, 22b with a bolt inserted into a screw hole formed in the fastening portion on each side. In the box body of the closed switchboard configured as described above, the left ceiling plate 22A and the right ceiling plate 22B are compatible with the front ceiling plate 21A and the rear ceiling plate 21B, and the net plate 23 is included. Since the number of types of parts is reduced to three quarters as compared with the conventional ceiling board, the production is easy due to the effect of mass production.

In addition, since there is no protrusion on the lower surface of the ceiling plate that obstructs the flow of air, the flow of air warmed inside the box to the opening is improved and the cooling effect is improved.

Further, the five ceiling plates are overlapped and fastened by the L-shaped fastening portions on the opposite sides, and in particular, since the fastening portions 22a and 22b extend to the front and rear ends of the box body 11, the rigidity is increased and each ceiling plate is tightened. It is possible to prevent the deflection due to the weight of the weight and the weight of the upper drip-proof plate.

(Effect of the Invention) As described above, according to the box body of the closed switchboard of the present invention, one side is bent to one side and the other side of the upper surface of the ceiling part of the box body provided with the intake port at the lower portion of the outer wall. The fastening portions of the plates are attached so as to face each other, and between the first ceiling plate, a pair of second ceiling plates of the same shape with three sides bent are symmetrically attached, and the first ceiling plate and the second ceiling plate are attached. A mesh plate with four sides bent was attached to the central opening formed by the plate, and these fastening parts were tightened, so that the ceiling part is prevented from bending, and it is easy to manufacture and the internal warm air discharge effect is improved. It is possible to obtain a box body of a closed switchboard.

[Brief description of drawings]

FIG. 1 is a partially exploded perspective view showing an embodiment of a box body of a closed switchboard according to the present invention, FIG. 2 is an exploded perspective view of a ceiling portion shown in FIG. 1, and FIG. FIG. 4 is a perspective view showing a box body of the switchboard, FIG. 4 is an enlarged cross-sectional view taken along the line AA of FIG. 3, and FIG.
FIG. 6 is an explanatory view showing the operation of a conventional closed switchboard box. 3 ... Door, 3a ... Intake port, 11 ... Box, 21A ... Front ceiling plate, 21B ... Rear ceiling plate, 22A ... Left ceiling plate, 22B ... Right ceiling plate, 23 ... Mesh plate .

Claims (1)

[Scope of utility model registration request] 1. A box body of a closed switchboard in which an intake port is provided at a lower portion of an outer wall, an electric power device is housed inside, and a ceiling plate is provided at an upper end of the box body. On the upper surface of the box body so as to face each other between the first pair of ceiling plates that are provided to face each other and have L-shaped fastening portions provided upright on the opposite sides. The second ceiling plate is provided between the second pair of ceiling plates, the second pair of ceiling plates having L-shaped fastening portions provided upright on the opposite side between the first ceiling plate and the opposite side. A box body for a closed switchboard, comprising an inverted L-shaped fastening portion formed on a side and configured by a third ceiling plate for discharging air in the box body.