JPH08168119A - Dust-proof structure of closed power distribution panel - Google Patents

Abstract

PURPOSE: To prevent dust from entering from the outside of a box body through an electric wire through part of a closed power distribution panel and to facilitate assembly. CONSTITUTION: A hole part 2 for leading electric wire is formed at a box body 1 for housing electrical equipment and an electrical wire 4 passes through the hole part 2. A screening member is provided between the electric wire 4 and the hole part 2. The screening member is provided with a hollow member 7 consisting of rubber tube and is sandwiched by frame bodies 8 and 9. The hollow member 7 expands so that the electrical wire 4 is clamped after media such as air and water are injected inside the hollow member 7, thus screening the surrounding of the electrical wire 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dustproof structure for a closed switchboard which prevents dust from entering the inside of a box containing electrical equipment.

[0002]

2. Description of the Related Art Generally, a closed switchboard is constructed by accommodating an electric device such as a circuit breaker for a main circuit device, a transformer, or an auxiliary relay for a control circuit device, a meter, etc. inside a box. Depending on the location, dust may enter the inside of the box and cause malfunction of the electric device. For this reason, there is a device configured as shown in FIG. 4 in order to suppress the intrusion of dust. That is, the floor board 3 as a shielding member having the wire lead-in portion 3a is attached to the wire lead-in hole 2 formed in the bottom portion of the box 1 of the closed switchboard, and the wire 4 is attached to the wire lead-in portion 3a of the floor board 3. After pulling in, the electric wire 4 and the electric wire pull-in portion 3a
And a putty-like sealant 5 is applied between and.

[0003]

As described above, by applying the sealant 5 between the electric wire drawing portion 3a and the electric wire 4,
Although it is possible to prevent dust from entering from the outside of the box body 1 through the electric wire lead-in portion 3a, various electric wire lead-in portions 3a are provided on the floor plate 3 according to the number and thickness of the electric wires 4 passing through the floor board 3. It is necessary to form it. In this case, since the floor plate 3 is made of a steel material or a plastic material, it takes a lot of time to process it.

In assembly, the floor board 3 is once removed when the closed switchboard is installed, and the wire lead-in portion 3 is attached to the floor board 3.
After forming a, it was necessary to attach it to the box body 1 again, pull in the electric wire 4, and then apply the sealant 5, and it took much time to assemble.

The present invention has been made in view of the above circumstances, and its purpose is not only to prevent dust from entering from the outside of the box through the wire penetration portion of the closed switchboard, but also to provide a closed switchboard which is easy to assemble. To provide a dustproof structure.

[0006]

In order to achieve the above-mentioned object, the present invention allows an electric wire to pass through a hole formed in a box containing electric equipment, and the electric wire and the hole. In the structure in which the shielding member is provided between the two, a hollow body in which a medium is injected and expanded is used as the shielding member.

In this case, the hollow body may be provided with an openable / closable inlet for injecting the medium. Further, as the medium, a material that is solidified when it is in contact with air as a liquid when enclosed in a hollow body can be used. Further, the hollow body may be housed in the frame body, holes may be provided in the frame body and the hollow body, and the frame body may be attached to the hole portion of the box body.

[0008]

According to the first aspect of the present invention, since the expanded hollow body has the dustproof structure, it is not necessary to process the wire lead-in portion according to the number and thickness of the wires.
According to the second aspect of the invention, the medium can be injected and discharged through the openable / closable inlet, so that the electric wire can be easily drawn in and drawn out.

According to the third aspect of the present invention, since the medium enclosed in the hollow body is solidified when it comes into contact with air, even if the hollow body is broken, the medium is solidified and the dustproof structure is not damaged. According to the invention described in claim 4, the hollow body is housed in the frame body, so that the damage to the hollow body can be reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1 showing the bottom of the box of the closed switchboard, the box 1 has a circuit breaker, a transformer, and a main circuit device inside.
Alternatively, it accommodates an electric device such as an auxiliary relay of a control circuit device or a meter, and a hole 2 for drawing in an electric wire is formed at the bottom thereof. A shield member 6 is attached to the hole 2 for drawing in the electric wire. As shown in FIGS. 2 and 3, the shielding member 6 has a hollow body 7 made of a rubber tube, and the hollow body 7 is sandwiched between upper and lower sides of a lunch box-shaped frame body 8 and 9. . Electric wire through holes 7a, 8a, 9a are formed in the hollow body 7 and the frames 8, 9 respectively, and the electric wire 4 is drawn in through these through holes 7a, 8a, 9a. The hollow body 7 is provided therein with an injection port 7c for injecting a medium composed of a gas such as air or a liquid such as water, and the injection port 7c is drawn out through a hole 8b formed in the upper frame body 8. It can be opened and closed with the stopper 10. Frame 8,
9 is provided with mounting holes 8c and 9b, and the entire shielding member 6 is fixed to the floor of the box 1 by bolts 11 through the mounting holes 8c and 9b.

Next, the function and effect of the present invention will be described.
As shown in FIG. 1, when the closed switchboard is installed, the shielding member 6
Is fixed to the floor of the box 1 in advance with bolts. Then, the electric wire 4 is drawn into the box body 1 through the through hole of the shielding member 6. After that, a medium such as air is injected from the injection port of the hollow body 7, and the hollow body 7 is expanded so as to tighten the electric wire 4. Then, the plug 10 is attached and sealed so as to maintain the state.

As a result, the hollow body 7 shields the periphery of the electric wire 4 and prevents dust from entering through the electric wire drawing hole 2 provided in the box body 1. When pulling out the electric wire 4, if the plug 10 of the hollow body 7 is removed and the medium inside the hollow body 7 is discharged, the electric wire 4 can be pulled out easily.

By thus using the expandable and contractible hollow body 7 for the shielding member 6, a dustproof structure can be easily provided regardless of the number and thickness of the electric wires 4. Moreover, since the hollow body 7 is only expanded, it is not necessary to process the shielding member in correspondence with the number and thickness of the electric wires 4. Therefore, unlike the conventional case, when installing the closed switchboard, the floor plate is removed, the electric wire lead-in portion is processed, and then the floor plate is not attached again, which facilitates the assembly.

In the above-described embodiment, the shielding member 6 is formed by sandwiching the hollow body 7 between the frames 8 and 9. With this configuration, the assembly into the box 1 is facilitated and the damage to the hollow body 7 can be reduced. However, for example, the frames 8 and 9 can be eliminated and the hollow body 7 can be directly attached to the box 1. Even if it is attached, the dustproof structure can be easily assembled.

Further, as a medium to be injected into the hollow body 7, it is solidified by being in contact with air as a liquid in a state of being enclosed in the hollow body 7. For example, if a coating agent is used, the hollow body 7 should be used.
Even if it is broken, the coating agent is solidified, so that the dustproof structure is not damaged.

[0016]

As is clear from the above description, according to the present invention, the inside of the box is filled with a medium as a shielding member between the electric wire and the hole of the box containing the electric device. By using the expanded hollow body, it is not necessary to process the wire lead-in portion according to the number and thickness of the wires, and the assembly can be easily performed.

Further, by providing an openable / closable inlet for injecting the medium into the hollow body, the electric wire can be easily pulled in and out. Furthermore, by using a material that solidifies when it comes into contact with air as a liquid when enclosed in a hollow body as a medium,
Even if the hollow body is broken, the medium does not solidify and the dustproof structure is not damaged. Further, since the hollow body is housed in the frame body, damage to the hollow body is reduced and the assembly is easy.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of a dustproof structure for a closed switchboard according to the present invention.

FIG. 2 is a perspective view showing a shielding member used in FIG.

FIG. 3 is an exploded perspective view showing a shielding member used in FIG.

FIG. 4 is a perspective view showing a dustproof structure of a closed switchboard having a conventional configuration.

[Explanation of symbols]

1 is a box, 4 is a cable, 6 is a shielding member, 7 is a hollow body,
7a, 8a and 9a are through holes, 7c is an inlet, 8 and 9 are a frame, and 10 is a stopper.

Claims (4)

[Claims] 1. An electric wire is passed through a hole formed in a box containing electric equipment, and a shielding member is provided between the electric wire and the hole.
A dustproof structure for a closed switchboard, which is characterized by using a hollow body that is expanded by injecting a medium into it. 2. The dustproof structure for a closed switchboard according to claim 1, wherein the hollow body is provided with an openable / closable inlet for injecting a medium. 3. The dustproof structure for a closed switchboard according to claim 1 or 2, wherein a material that is liquid and solidifies when it comes into contact with air in a state of being enclosed in the hollow body is used as the medium. 4. A hollow body is housed in a frame body, holes are formed in the frame body and the hollow body for electric wires to pass through, and the frame body is attached to a hole portion of a box body. 4. The dustproof structure for a closed switchboard according to any one of 3 to 3.