JPH08330777A - Panel protecting structure - Google Patents

Abstract

PURPOSE: To protect a panel against electromagnetic interference meeting the requirements prescribed by IP 54 by a method wherein a second soft protective member is provided between a case and a closing member surrounding the periphery of an opening outside a first protective member for hermetically sealing the case. CONSTITUTION: Door packings are provided to the inner side of a door 12 as a second protective member for a board. An upper door packing 18a and a lower door packing 18b are provided along the upper and lower edge of the door 12. Side door packings 18c and 18d are provided along the crosswise vertical edges of the door 12. Conductive overhangs of sheet metal member are provided as first protective members to an upper flange 14a, a lower flange 14b, and side walls 20b and 20c respectively. The door packings 18a, 18b, 18c, and 18d are brought into contact with bearing faces 14c, 14d, 20d, and 20e, whereby a cavity is flexibly deformed to hermetically seal up the opening of the case.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective structure for a control panel or a switchboard for accommodating electric machines and electronic equipment.

[0002]

2. Description of the Related Art Conventionally, in order to prevent an electromagnetic interference (EMI), a control panel or a switchboard (hereinafter, simply referred to as a panel) for accommodating electric machines and electronic devices is closed at the opening of the panel. An electromagnetic wave shielding member or EMI packing is provided so that it can come into contact with the door. The EMI packing is formed by coating or impregnating the surface of a rubber sponge with a conductive material such as silver. For this reason, the EMI packing can block electromagnetic waves that cause noise, but the member itself lacks flexibility and elasticity and is waterproof.
Since the dustproof property is also inferior, a gap is liable to be formed between the EMI packing and the door, and it is impossible to prevent intrusion of solid foreign matter such as dust or dust or oil or water.

On the other hand, for the purpose of protecting the board from solid foreign substances other than electromagnetic waves, water, and gas, the Japanese Electrical Manufacturers' Association standards refer to a protection structure (hereinafter referred to as a protection structure) by an outer cover of the board. , "Type of protective structure of switchboard / control panel" (hereinafter referred to as JEM-1267). In JEM-1267, protection of a board against intrusion of solid foreign matter is classified into protection type 1, and protection against intrusion of water is classified into protection type 2.

FIG. 5 shows an example of a conventional protective structure for a solid foreign matter and water intrusion of a board. In the protection structure of FIG. 5, one end of the side wall 30 of the board is bent inward by sheet metal working to form a flange portion with which the door 32 abuts. The door 32 is a substantially rectangular sheet metal member, and is provided with waterproof and dustproof packing 34 along the edge thereof. The packing 34 is a rubber-made hollow packing, and when contacted with the flange portion, the contact portion is flexibly deformed to enhance the sealing effect. The protective structure of FIG. 5 can provide a dustproof and waterproof effect of about IP34 (the first symbol of the standard is 3 and the second symbol is 4). In other words, regarding the entry of solid foreign matter, "a tool whose diameter or thickness exceeds 2.5 mm,
The tips of solid objects such as wires do not enter inside. With regard to water invasion, "it is not adversely affected by water splashing from any direction." However, if a degree of protection of IP54 is required, ie "1.0 mm diameter or thickness"
The tip of a solid object such as a wire or steel strip that does not reach the inside does not enter inside. 5 and “Prevent dust from entering inside. Even if a little dust enters, it does not impede normal operation.”
It is not possible to cope with the protection structure of. That is, packing 3
No. 4 can prevent dust from entering, for example, wire 36
The wire 36 between the packing 34 and the board.
Pushes the packing 34 away, and the arrow A
It is possible to enter the board in the direction of.

[0005]

The object of the present invention is to solve the problems of the prior art.
It is an object of the present invention to provide a board protection structure capable of achieving the degree of protection of IP54 while protecting the board from damage due to electromagnetic waves.

[0006]

According to the present invention, there is provided a housing having an opening for accommodating an electric machine and an electronic device therein, a closing member for closing the opening of the housing, the housing and the closure. An electromagnetic wave shielding member provided so as to surround the peripheral portion of the opening between the member and the member, so that when the opening is closed by the closing member, contact is possible over the entire length of the surface of the electromagnetic wave shielding member. A conductive first protection member provided, and a housing provided between the housing and the closing member so as to surround a peripheral portion of the opening on the outside of the first protection member. A board comprising a flexible second protective member for sealing between a cover and a closing member.

[0007]

When the opening of the housing is closed by the closing member, the conductive first protection member comes into contact with the housing over the entire length of the surface of the electromagnetic wave shielding member that surrounds the opening of the housing. Electromagnetic waves are prevented from leaking into the board from the opening passing through between the body and the closing member.

When the opening of the housing is closed by the closing member, the second protective member surrounding the opening of the housing flexibly deforms to seal the opening and prevent intrusion of solid foreign matter and water. To do. More specifically, with respect to the intrusion of a solid object, "the tip of a solid object such as a wire or a steel strip having a diameter or a thickness exceeding 1.0 mm does not intrude into the inside." Prevents invasion into the interior. Even if there is a slight amount of dust intrusion, normal operation is not hindered. ”Is achieved, and in response to water intrusion,“ water is splashed from any direction. , Not adversely affected. "Can be achieved. That is, JEM-126
A classification of 7 gives a degree of protection of IP34.

Further, the first protection member provided inside the second protection member comes into contact with the tip of a solid object such as a wire which has pushed into the board by pushing the second protection member, and further Since the entry of solid objects is prevented, "the tip of solid objects such as wires and steel strips having a diameter or thickness exceeding 1.0 mm does not enter the inside" against the entry of solid objects, and IP54 protection is achieved. Can be obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to FIGS. The board 10 according to the present invention includes a housing 14 having an opening that opens forward and a door 12 as a closing member that closes the opening of the housing 14. The housing 14 is formed by processing a thin plate into a substantially rectangular parallelepiped shape. The door 12 is attached rotatably around one vertical side of the opening of the housing 14. More specifically, the door 12 includes an upper rotation support portion 12a provided on a top plate 20a attached to the upper frame 14a,
Bracket 14d attached to lower frame 14b
The lower rotation support portion 12b provided on the
Is rotatably attached to one side of the vertical direction, and the opening can be opened by rotating the door 12 forward.

In the present embodiment, the board 10 is provided with a door packing, which will be described below, as a second protective member on the inner surface of the door 12. Upper and lower door packings 18a, 1 along the upper edge and the lower edge of the inner surface of the door 12
8b is extended. Upper and lower door packing 1
8a and 18b project inward from the inner surface of the door 12, and are provided so as to contact the outer contact surfaces 14c and 14d of the upper and lower frames 14a and 14b when the door 12 is closed. Similarly, the side door packings 18c and 18d are provided along both vertical edges of the inner surface of the door 12.
Has been extended. Side door packing 18c, 18d
When the door 12 is closed, the side walls 20b, 20c
Is provided so as to contact the contact surfaces 20d and 20e formed by bending inward. The door packing 18
a, 18b, 18c and 18d are known packings having a cavity inside, as described with reference to FIG.
When it comes into contact with the contact surface, it is deformed flexibly to seal the peripheral edge portion of the opening portion and provide a dustproof and waterproof effect of about IP34.

Further, the inner surface of the door 12 is provided with an electromagnetic wave interference preventing packing (hereinafter referred to as EMI packing) as an electromagnetic wave shielding member. Specifically, the upper EMI packing 16a is horizontally extended above the inner surface of the door 12 inside the upper door packing 18a, and the lower EMI packing 16b is horizontally below the inner surface of the door 12 inside the lower door packing 18b. Is extended in the direction. Further, inside the side door packings 18c and 18d, side EMI packings 16c and 16d are provided vertically on both sides of the inner surface of the door 12. The EMI packing is a known packing for preventing electromagnetic interference, and is formed on the outer surface of a long rubber sponge member having a substantially rectangular cross section.
A conductive material such as silver is coated or impregnated.

The board 10 of this embodiment, as will be described below, has upper and lower flanges 14 as a first protective member.
a, 14b and side walls 20b, 20c are provided with overhanging portions made of a conductive sheet metal member. The upper and lower overhang portions 22a and 22b are attached to the upper frame 14.
a and contact surfaces 14c of the lower frame 14b, 1
4d projecting outwardly, and the upper and lower overhang portions 22a and 22b are horizontally extended so as to contact the entire length of the upper and lower EMI packings when the door 12 is closed. ing. Similarly, on the side walls 20b and 20c of the board 10, the side EMI packing 16c,
Side projections 22c and 22d are arranged at positions facing 16d. The side protrusions 22c and 22d are also the door 1
Side EMI packings 16c, 16 when 2 is closed
It is extended in the vertical direction so as to make contact over the entire length of d. The overhanging portion is electrically conductive so that the EMI packing can be grounded when the door 12 is closed and comes into contact with the surface of the EMI packing. For this reason, in particular, it is necessary to prevent the tip of the overhanging portion from being covered with a coating material having no conductivity.

Next, the operation of the embodiment shown in FIGS. 1 to 3 will be described. When the door 12 is rotated outward about the rotation support portions 12a and 12b, the opening of the housing 14 is opened. At this time, the door packings 18a, 18b, 18c,
18d and EMI packings 16a, 16c, 16d,
16d rotates with the door 12 around the rotation supporting portions 12a and 12b. As a result, the door packing 18
a, 18b, 18c and 18d are contact surfaces 14c and 14d,
Separated from 20d and 20e, EMI packing 16a, 1
6c, 16d and 16d are the projecting portions 22a, 22b and 22.
Separated from c and 22d. When the door 12 is closed as shown, the door packings 18a, 18b, 18c, 18d
Contacts the contact surfaces 14c, 14d, 20d, 20e, and the overhanging portions 22a, 22b, 22c, 22d are EMI at the tips.
It contacts the surfaces of the packings 16a, 16c, 16d, 16d.

Door packings 18a, 18b, 18c, 1
By contacting the contact surfaces 14c, 14d, 20d, and 20e, 8d flexibly deforms the hollow portion to seal the opening of the housing 14 and effectively prevent intrusion of solid objects and water. More specifically, with respect to the intrusion of a solid object, "the tip of a solid object such as a wire or a steel strip having a diameter or a thickness exceeding 1.0 mm does not intrude into the inside." Prevents invasion into the interior. Even if there is a slight amount of dust intrusion, normal operation is not hindered. ”Is achieved, and in response to water intrusion,“ water is splashed from any direction. , Not harmed. ”Is achieved. That is, according to the classification of JEM-1267, the degree of protection of IP34 can be obtained.

Further, as shown in FIG. 5 by way of example, solid objects that push the door packing and enter from between the door packing and the abutting surface are overhanging portions 22a, 22b.
22c and 22d are abutted to prevent further intrusion, so that the invasion of a solid object may be reduced by "diameter or thickness 1.
The tips of solid objects such as wires and steel strips exceeding 0 mm do not enter inside. Is achieved and a degree of protection of IP54 can be obtained. And the door packing 18
a, 18b, 18c, 18d and contact surfaces 14c, 14d,
Electromagnetic waves leaking from between 20d and 20e are overhanging part 2
The tips of the 2a, 22b, 22c and 22d are prevented from being in contact with the surfaces of the EMI packings 16a, 16c, 16d and 16d.

Although the preferred embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above-mentioned embodiments,
It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. For example, in FIGS. 1 and 2, the EMI packing is simply the door 1
Although attached to the inner surface of No. 2, as shown in FIG. 4, a reinforcing member 28 formed in a U-shape is attached to the inner surface of the door 12, and the EMI packing 16 is attached to the inner surface of the reinforcing member 28.
You may attach a, 16c, 16d, 16d.

In the illustrated embodiment, the door packing and the EMI packing are mounted on the inner surface of the door 12, but they may be mounted on the housing 14 side. In short, the door packing and the EMI packing are, when the door 12 is closed,
The door 12 and the housing 14 surround the opening of the housing 14.
It may be provided between.

[0019]

As is apparent from the above description, according to the board protection structure of the present invention, it is possible to achieve the degree of protection of the IP 54 while protecting the board from damages caused by electromagnetic waves.

[Brief description of drawings]

1 is a partial cross-sectional view of a preferred embodiment of the present invention,
It is sectional drawing which follows the arrow line I-I of FIG.

2 is a partial cross-sectional view of the preferred embodiment of the present invention, FIG.
It is sectional drawing which follows the arrow line II-II of FIG.

FIG. 3 is a schematic perspective view of a board to which the present invention is applied.

FIG. 4 is a cross-sectional view for explaining a method of attaching the EMI packing.

FIG. 5 is a cross-sectional view of a protection structure against solid foreign matter and water intrusion according to the prior art.

[Explanation of symbols]

 10 ... Board 12 ... Door 14 ... Housing 16a ... EMI Packing 16b ... EMI Packing 16c ... EMI Packing 16d ... EMI Packing 18a ... Door Packing 18b ... Door Packing 18c ... Door Packing 18d ... Door Packing 22a ... Overhang 22b ... Overhang 22c ... Overhang 22d ... Overhang

Claims (1)

[Claims] 1. A housing having an opening therein for accommodating an electric machine and an electronic device, a closing member for closing the opening of the housing, and the opening between the housing and the closing member. An electromagnetic wave shielding member provided so as to surround a peripheral edge of the electromagnetic wave shielding member, and a conductive first member provided so as to be contactable over the entire length of the surface of the electromagnetic wave shielding member when the opening is closed by the closing member. And a sealing member provided between the housing and the closing member so as to surround a peripheral portion of the opening on the outer side of the first protecting member and between the housing and the closing member. And a flexible second protection member.