JPH034111Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] This invention relates to an airtight dust-proof device in wiring boxes, and is useful in clean rooms installed to clean the working environment in many industrial fields.
This invention relates to an airtight dustproof device that ensures airtightness and dustproofing of indoor electrical outlets, switches, sensors, and other wiring mechanisms.

[Technical background of the invention and its problems] Recently, with the development of industry and medicine, there has been an increase in the electronics industry, precision industry, pharmaceutical manufacturing industry, food industry, optical machinery industry, construction of laboratory animal housing, and many other industries. Cleanliness of the working environment is required across industrial fields, and clean rooms are being installed in each field. During this clean room installation work, we will ensure that the seal is completely sealed to ensure airtightness and no air leakage.
Strict conditions are imposed, including that there be no cracks and that the structure is designed to prevent contaminant particles from falling from walls and ceilings due to vibration. Particularly, in the case of an indoor outlet, switch, or sensor, since electric wires are drawn into the wiring box from the outside, the interior must be kept airtight. Therefore, conventionally,
After installing the wiring box to which the conduit is connected by the usual method behind the installation opening in the building frame,
The sealing material is inserted into the opening of the building frame, and the parts that communicate with the outside of the wiring box, such as the knock-out edges, small mounting holes, insulating bushings that connect electrical conduits, the area around the box cover, etc., are manually sealed. In this case, the wiring box may be made of hard vinyl resin without knockouts, or the conduit may be made of the same material. Next, the electric wire, which has been sealed at the insulating bushing part pulled out from the inside of the conduit, is connected to an electric mechanical component such as an outlet body, a switch body, or a sensor body attached to the mounting frame, and the installation opening is Rubber gaskets are placed around the periphery of the parts and fixed to the mounting frame with screws.

During such construction, the seal is checked several times to ensure a perfect seal, and when the equipment is installed, the seal condition is checked again and any defective parts are corrected. However, it was difficult to seal the inner surface of the wiring box and the insulating bushings, and there was a lot of air leakage.
They are often extremely incomplete, and since there are many sealing points and a large amount of sealing material is used, work efficiency is poor, construction costs are high, and it is difficult to inspect and confirm air leaks. In particular, when inserting and setting electrical mechanical parts into a wiring box, the wires tend to wobble, causing gaps at the insulating bushings, and it sometimes takes time for the sealant to adhere.

In order to solve this problem, the present applicant filed a patent application filed in 1983-
As No. 33775, we proposed an airtight dust-proof device installed inside the wiring box. Its structure forms a box body made of an airtight material that covers electrical mechanical parts such as the outlet main body and the switch main body, which are inserted and set into a wiring box that is supported and fixed on the back side of the installation opening opened in the building frame. An abutting flange that closely contacts the periphery of the installation opening is provided on the periphery of the opening of the box body, and an airtight wire extraction means into which an electric wire can be inserted is attached to the bottom wall of the box body.
However, since this entire device is made of a soft material with a high degree of hardness, when it is used and installed, the abutment flange that is in close contact with the periphery of the installation opening is strongly pressed by the mounting frame. When
The periphery is deformed, resembling waves,
There were times when it was difficult to ensure perfect airtightness. Also,
Even after installing the decorative plate, the deformation was severe.
It was found that only unreliable cosmetic treatments could be performed and could result in unsightly appearance.

[Purpose of the invention] This invention was created in view of the above-mentioned conventional circumstances and to eliminate these drawbacks, and it is possible to solve the problems of the inside of wiring boxes and insulating bushings, which were extremely troublesome to install in the past. Eliminate the need for sealing, improve work efficiency, reduce overall construction costs, limit locations where air leaks can occur, facilitate inspection, and improve the abutment flange area. The purpose of this is to prevent deformation in the air and further improve airtightness.

[Summary of the invention] In order to achieve the above-mentioned purpose, in this invention, an outlet main body, a switch main body or In an airtight dust-proof device, a box body made of an airtight material is formed to cover electrical mechanical parts such as the sensor body, and the bottom wall of the box body is equipped with an airtight wire extraction means that allows the insertion of electric wires. The present invention consists in that an abutment flange that is in close contact with the periphery is extended around the opening periphery of the box body, and a core plate made of a hard material is attached to the abutment flange in an embedded manner.

[Embodiments of the invention] Hereinafter, embodiments of the invention will be described with reference to the drawings.

The reference numeral B shown in the figure refers to a switch box that houses a conventional switch body, an outlet box that houses an outlet body, an outlet box that branches cables, etc., or various sensors such as heat detectors and gas detectors. This wiring box B is a wiring box that stores the main body, and this wiring box B connects a box cover C attached to the opening of this wiring box B to an installation opening H opened in a building frame W such as a wall or ceiling surface in a clean room. By positioning it, it is supported and fixed on the back side of the building frame W by a known fixing means (not shown). Further, an electric conduit P through which an electric wire G of a predetermined diameter is passed is connected to the wiring box B by a lock nut N and an insulating bushing I. In any case, the wiring box B and conduit P may be made of metal that has been commonly used.
There are no restrictions on materials, and there are no differences from conventional construction procedures.

Then, inside the wiring box B, an airtight box 1 made of an airtight material is charged and set, which seals and partitions the inside of the clean room and the outside of the clean room. This airtight box 1 has a box body 2 formed in a box shape so as to cover an electric mechanical part E such as an outlet main body, a switch main body, or a sensor main body located in the installation opening H. The bottom wall of the body 2 is provided with an airtight wire extraction means into which an electric wire can be inserted. box body 2
The material is, for example, made of butyl rubber (IIR), which has a very low permeability to water vapor and gas.
By doing so, it is possible to improve workability by utilizing the softness of the material itself.

Then, an abutment flange 3 that abuts the periphery of the installation opening H is extended to the periphery of the opening of the box body 2, and a hard material core plate 4 is embedded in the abutment flange 3. For example, if the surface of the abutment flange 3 with a wall thickness of 3 mm is a core plate 4 made of a galvanized iron plate and shaped like a flat donut with a wall thickness of 1.2 mm, the surface of the core plate 4 is used as the surface of the abutment flange 3. It is to be buried flush. Therefore, the core plate 4 can be attached to the abutment flange 3 at the same time as the airtight box 1 itself is vulcanized and molded, and can be easily integrated without using any special adhesive fixing method. is possible. In addition, 5 in the figure is a groove molded on the back surface of the abutment flange 3, which is disposed so as to surround the box body 2 over the entire area of the abutment flange 3, and is in a state where it is strongly pressed by the mounting frame F. facilitates elastic deformation that occurs in the material itself at the abutment flange 3 when it is clamped between the installation opening H and the abutting flange 3;
This improves adhesion.

The electric wire drawing means 6 has an inner diameter corresponding to the outer diameter of the electric wire G to be drawn out, and is preferably formed into a cylindrical shape that can be penetrated and is closed, and is disposed to protrude outward from the bottom wall. For example, a total of 6 protrusions, 3 on the upper tier and 3 on the lower tier, are provided to protrude in accordance with the number of lead wires so as to seal each electric wire G, and are integrated with or connectable to the box body 2. It is constructed separately from the same material as 2.

The wire drawing means 6 shown in the figure is formed separately from the box body 2, which is the main body of the airtight box 1, so that it can be used in combination to accommodate the different diameters of the wires G to be drawn in. The electric wire draw-out tube 10 is provided. That is, the first
As shown in FIGS. 3 and 3, a thick ring-shaped connecting annulus 9 is formed on the bottom wall of the box body 2 around a penetrable thin film-like closure seal 8 to form a drawer portion 7.
The electric wire pull-out tube 10 is connected to this pull-out part 7, and the specific structure of the electric wire pull-out tube 10 is as follows. Appropriate number of presser ribs 1
2 is raised, and a joint opening 13 is provided at the rear of the insertion cylinder 11 to be connected to the connecting ring 9 in an internal or external fitting manner.
Insertion openings 15 are formed in the front portion of the insertion cylinder 11, respectively, and are closed with penetrable thin film-like closing pieces 14. In addition, 16 is a guide tube formed to protrude in the shape of a flap toward the front of the insertion port 15 to ensure smooth insertion guidance of the electric wire G, and 17 is a joining flange provided in the shape of a flange on the outer periphery of the joint port 13. When bonded to the body 2, the bonding stability is improved by coming into close contact with the surface of the connecting ring 9. In addition, as shown in the figure, by opening the inner surface of the connecting ring 9 in a truss-like shape, it is possible to facilitate the joining operation and to achieve a reliable connection.

Therefore, there are several types of wire extraction tubes 10 having different inner diameters of the insertion cylinder 11, for example, 3.2φ, 3.6φ,
By preparing a 4φ one, you can select and use one that corresponds to the wire G diameter, and connect the joint port 1 with adhesive.
3 to the connecting ring strip 9. Then, the closing piece 14 and the closing seal 8 may be opened with a cutter or other cutting tool or directly with the electric wire G, and the electric wire G may be forcibly inserted therethrough. An adhesive or the like may be filled between the periphery of G and the inner circumferential surface of the insertion cylinder 11.
For this reason, the box body 2 and the wire outlet tube 10
Compared to the case where the wires are integrally formed, there is no need to prepare separate manufacturing molds for different diameters of the electric wire G, and the product yield during molding is improved and the product can be provided at low cost. In addition, when the number of electric wires G is small, the closed seal 8, which is not used and opened, ensures a sealed compartment inside and outside the airtight box 1, and the holding rib 12 of the insertion cylinder 11 is crimped to the outer periphery of the electric wire G. This effectively helps maintain airtightness.

When the airtight box 1 configured as described above is loaded and set so as to cover the electrical mechanical parts E, the back side of the abutting flange 3 is coated with double-sided adhesive tape and adhesive to form a clean room building frame W. The surface of the contact flange 3 is brought into contact with the back surface of the mounting frame F to which the electrical mechanical component E is attached. The mounting frame F itself is usually connected to the box cover C by screwing the mounting screws 18 into the box cover C so that the mounting screws 18 are inserted into the box cover C. A through-insertion part 19 is formed to be inserted. The penetrating portion 19 is located outside the box body 2 and protrudes in a cylindrical shape behind the abutting flange 3, and is closed with a thin film-like closing membrane 20 that can be penetrated through the tip opening. This is what I did. The occlusive membrane 20 is opened with a cutter or other cutting tool or directly with the mounting screw 18.

After that, the decorative cover D is screwed to the mounting frame F using a normal method.

Further, in FIG. 5, another embodiment is shown. That is, this is configured to be compatible with a constant temperature spot sensor having a circular shape, and a circular abutting flange 3 is provided extending from the opening edge of a box body 2 having a substantially rectangular parallelepiped shape. The rigidity of the abutting flange 3 is made by attaching the core plate 4 embedded in the abutting flange 3 in the same manner as described above.

Next, the construction procedure will be explained with reference to FIGS. 2 and 4. The back side of the installation opening H opened into the building frame W by combining the wiring box B, conduit P, and box cover C as in the conventional case. Support and fix it with , and pass the electric wire G through it. Next, the electric wire G is inserted from the outside of the electric wire drawing means 6 in the airtight box 1 (the fourth
(see figure), while connecting to the electrical mechanical component E mounted on the mounting frame F, the box body 2 in the airtight box 1 is placed over the electrical mechanical component E. After that, with the contact flange 3 in airtight contact with the periphery of the installation opening H of the building frame W, the mounting frame F is screwed to the box cover C, and the decorative cover D is screwed to the mounting frame F, respectively. (See Figure 2).

[Effects of the invention] This invention is configured as described above, and as a result, it is possible to
In the case of switches, sensors, and other wiring mechanism parts, the airtight box 1 reliably separates the inside and the outside, so there is no need for sealing with a sealing material, which was conventionally performed. Therefore, compared to the conventional method of sealing each location manually, which could only seal 5 to 6 locations per work day, the work can be performed several times more efficiently and construction costs can be reduced. Significant savings can be made. Furthermore, when inspecting and confirming after construction, there are only two places where air leakage can occur: the 6 parts of the wire pull-out means and the 3 parts of the contact flange in the airtight box 1, so inspection is extremely easy. It is also very easy to repair leaks once they are discovered.

In particular, in the wiring box B, the inside of the electrical conduit P connected to the wiring box B and the electrical mechanical component E that communicates with the clean room are completely separated by the airtight box 1 that covers the electrical mechanical component E. Since there is no air circulation between the two areas, it is possible to prevent dust and other particles present along the electric conduit P from entering the clean room, thereby maintaining the cleanliness of the room.
In addition, the airtight box 1 is made of an airtight material, and the wire pulling means 6 through which the electric wire G connected to the electric mechanical component E is inserted is sealed airtightly, so that air leakage is prevented at the portion where the electric wire G is inserted. Furthermore, since the abutting flange 3 on the periphery of the airtight box 1 is in close contact with the periphery of the installation opening H, there is no air leakage at all at the installation site.

Furthermore, since the abutment flange 3 has a hard material core plate 4 attached in an embedded manner, the attachment frame can be mounted with the abutment flange 3 in contact with the surface W of the building frame around the installation opening H. Even if F is attached and pressed like a hook with strong force, the abutment flange 3 itself will not be deformed in a wavy manner due to partial expansion and contraction as in the past, and the building frame W The entire area of the abutting flange 3 is brought into close contact with the entire surface in a uniform state.
Therefore, there is no leakage of air or intrusion of dust at the three abutment flanges, and the airtightness and dustproofing effects are further ensured.

Since the airtight box 1 is formed so as to cover the electrical mechanical component E, there is no need for separate sealing treatments using sealing materials on the inner surface of the wiring box B, the insulating bushing I part, etc., which is different from the conventional method. It does not require manual labor and is easy to install, which has excellent effects such as dramatically improving work efficiency.

[Brief explanation of the drawing]

The drawing shows one embodiment of this invention.
The figure is a partially cutaway exploded perspective view, Figure 2 is a sectional view in use, Figure 3 is an exploded sectional view of the main part, and Figure 4 is a sectional view with an electric wire inserted into the airtight box.
FIG. 5 is a partially cutaway exploded perspective view of another embodiment. B...Wiring box, C...Box cover,
D... Cosmetic cover, E... Electrical mechanism parts, F...
Mounting frame, G...Wire, H...Installation opening, I...
Insulating bushing, N...lock nut, P...conduit, W...building frame, 1...airtight box, 2
. . . Box body, 3 .
...Electric wire draw-out tube, 11...Insertion cylinder, 12
... Presser rib, 13 ... Joint port, 14 ... Closure piece, 15 ... Insertion port, 16 ... Guide tube, 17 ...
Joint flange, 18... Mounting screw, 19... Penetrating portion, 20... Occlusion membrane.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. Airtightness covering electrical mechanical parts such as an outlet main body, switch main body, or sensor main body inserted into a wiring box that is supported and fixed on the back side of an installation opening opened in a building frame. In an airtight dust-proof device that has a box body made of material and is equipped with an airtight wire extraction means that allows the insertion of electric wires into the bottom wall of the box body, the contact flange that is in close contact with the periphery of the installation opening is attached to the opening of the box body. An airtight dustproof device in a wiring box, which extends around the periphery and has a hard material core plate embedded in the abutting flange. 2. An airtight dust-proof device in a wiring box as set forth in claim 1 of the utility model registration claim, wherein the wire drawing means is integrally constructed with the box body. 3. An airtight dust-proof device in a wiring box according to claim 1, wherein the wire drawing means is configured separately from the same material as the box body so that it can be connected to the box body. 4. The wire drawing means is located on the bottom wall of the box body,
A thick ring-shaped connecting annulus is raised around the penetrable thin film-like closure seal to serve as a pull-out part, while a thick ring-shaped connecting annulus is formed along the circumferential surface of the insertion cylinder whose inner diameter corresponds to the outer diameter of the electric wire. The appropriate number of presser ribs are raised,
The electric wire draw-out tube has a joint opening to be connected to the connecting ring in the rear part of the insertion cylinder, and an insertion opening that is closed with a thin film-like closing piece that can be penetrated in the front part of the insertion cylinder. An airtight dustproof device in a wiring box according to claim 3, which is connected to a wiring box.