JP4402526B2 - Electrical equipment housing - Google Patents

Description

  The present invention relates to the structure of a casing of an electric device, for example, by properly blocking the inside and the outside of the casing of various electric devices such as a wired communication device, a wireless communication device, or a power transmission device. By ensuring the internal airtightness, it is useful for effectively preventing corrosion (rust) inside the casing.

  As a structure of a casing of a wired communication device arranged mainly outdoors, for example, a structure described in Patent Document 1 below is known. In the cases of these conventional wired communication devices, the inside and the outside are going to be shut off in a waterproof manner by using resin packing or the like.

FIG. 6 is a cross-sectional view of a contact portion between a case body and a lid of a case of a conventional wired communication device. The right side of the drawing is the outside of the housing, and the left side is the inside of the housing. The lid is configured to be openable and closable with respect to the case body, and the reference surface Σ of the contact portion is formed in a substantially flat shape. The packing p made of resin is formed in a ring shape, and its cross section is shown in this drawing. The case body and the lid are in surface contact at least around the point Q ₁ and the point Q ₂ on the reference plane Σ.

That is, the casings of these conventional wired communication devices have a contact surface between the case body and the lid on the outside (outside of the packing) of the packing.
JP2001-284847

  However, since a minute gap is generated in the surface contact portion between the case main body and the lid on the contact surface located outside the circumference of the packing as described above, it causes gap corrosion of the part, which is not desirable. In general, crevice corrosion of metal occurs from the difference in aeration caused by the action of a difference-difference battery based on the difference in oxygen concentration between the gap and the open part, and further corrosion occurs when chlorine ions enter the gap. To accelerate. Such corrosion usually tends to occur when there are gaps on the order of 1 μm to 10 μm.

Therefore, it is difficult to ignore these corrosions in securing the service life of the electric equipment and its casing. This is because when the crevice corrosion as described above expands, the corrosion reaches the periphery of the packing, which may reduce the sealing function of the packing and cause oxidation and corrosion of the metal surface inside the housing. Because. Furthermore, the airtightness is hindered by these oxidation and corrosion, moisture and the like enter the inside of the housing, and a predetermined electric circuit inside the housing causes a short circuit failure.
These problems need to be noted, for example, in salt-affected areas along the sea, since crevice corrosion progresses rapidly because there are many chlorine ions in the environment, and a particularly serious situation is likely to occur.

  The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a long-term connection between the inside and the outside of a housing of an electric device such as a wired communication device that is mainly arranged outdoors. And providing a means for effectively blocking, thereby ensuring the reliability and stability of the electrical circuit.

In order to solve the above problems, the following means are effective.
That is, the first means of the present invention includes a metal case body having a first flange formed around the opening, and a second case formed around the opening and contacting the first flange. An openable / closable electric device housing having a metal lid having a flange and an annular packing interposed between the first flange and the second flange. The flange is in surface contact with the packing on the inner space side of the housing, and a reference surface is formed by the contact surface. The first flange and the second flange are arranged in a region outside the packing. It is a surface parallel to the terrace and the reference surface of the case body, which is held in a non-contact manner in a certain edge region, is formed over the outer periphery of the edge region, opens to the outer periphery of the edge region, and is parallel to the reference surface. It consists of a minute gap between the lid and the ceiling surface. Between the lath and the reference surface, a communicating portion comprising a minute gap that connects a slit having a step difference in a position perpendicular to the reference surface and a storage groove for storing the slit and the packing. A first passage portion formed integrally with the first flange around the outer periphery of the first flange, and formed integrally with the second flange around the outer periphery of the second flange. A second fastening portion that is in surface contact with the first fastening portion, and the reference surface and the contact surface between the first fastening portion and the second fastening portion are perpendicular to the reference surface with respect to the reference surface. It has a step having different positions in the direction.

However, the flange does not necessarily have to protrude outwardly in a collar shape. The first flange corresponds to a cuff-like edge portion of the case body, and the second flange corresponds to a cuff-like edge portion of the lid.
In addition, of course, the above-described electric device includes a wired communication device and the like exemplified in the embodiments described later, but may be any other electric device. For example, a power transmission device used for power transmission or a wireless communication device may be used.
In addition, it is desirable to use a resin having a low wetting property for the packing.

  Further, the second means of the present invention is the above first means, wherein the shortest distance between the first flange and the second flange in the edge region is set to 0.1 mm or more and 1 mm or less. It is.

Further, according to the third means of the present invention, in the first or second means described above, the metal surface of the case body that touches the outside air even when the lid is closed, and the outside air even when the lid is closed. Both the metal surface of the lid to be touched and the metal surface of the contact portion that contacts the packing when the lid is closed are painted. Of course, it is desirable to perform coating with a high corrosion prevention effect on these metal surfaces.

In addition, a fourth means of the present invention is that in any one of the first to third means described above, at least a part of the metal surface inside the casing sealed by the packing is subjected to a chemical conversion film treatment.
Examples of the metal surface to be subjected to the chemical conversion film treatment inside the housing include a contact surface between metals or a contact surface between metal and packing. In addition, it is needless to say that when the coating is performed, it is better to perform the chemical conversion film treatment as a base treatment on the portion to be painted before the coating is performed. More preferably, the entire surface of the case main body and the lid may be subjected to a chemical conversion film treatment.

However, the chemical conversion film herein is generally called a chemical film, and refers to a protective film formed on the surface of aluminum or an aluminum alloy by a chemical reaction.
By the above means of the present invention, the above-mentioned problem can be effectively or rationally solved.

The effects obtained by the above-described means of the present invention are as follows.
That is, according to the first means of the present invention, there is no gap formed between the packing and the flange so as to cause differential airflow corrosion. Since the first flange and the second flange are not in contact with each other on the outer side of the packing, a gap having a minute interval is not formed so as to form a differential ventilation corrosion. For this reason, there is no difference in ventilation corrosion. For this reason, the sealing function of the packing is maintained better than before and for a longer period than before. Further, even if the contact surface between the case main body and the lid is formed inside the packing, there is no possibility that crevice corrosion will occur as long as the sealing function of the packing is maintained well.
Such an action / effect can be obtained more reliably by the synergistic effect of using a resin having low wettability as a material for the packing.
As described above, according to the first means of the present invention, the inside and the outside of the casing of the electrical equipment mainly disposed outdoors can be shut off over time, thereby The reliability and stability of the circuit can be ensured.

  It is even more desirable that the minimum distance between the case main body and the lid is 0.1 mm or more and 1 mm or less (second means of the present invention). That is, according to the second means of the present invention, it is difficult for water droplets to enter or remain, and the above-mentioned action and effect can be obtained more reliably, and at the same time, the durability of the packing is adversely affected. The ultraviolet rays of the sunlight that exerts the resistance to the packing are difficult to penetrate.

  Since the fastening part and the hinge part as described above are at least partially formed integrally with the case main body or the lid, the metal case main body and the metal lid are also formed in these parts (fastening part and hinge part). A contact surface is formed. Therefore, crevice corrosion is likely to occur even on such a contact surface.

However, according to this onset bright, and the height of the contact surface of the case body and the lid at these sites (fastening portion and the hinge portion), between the height of the slit, the above step is provided, which Thus, a long distance can be taken between the contact surface and the packing even in a limited narrow region where the flange is formed.
Therefore, according to this onset bright, corrosion sites based on crevice corrosion generated from the contact surface of the case body and the lid in the fastening portion and the hinge portion is significantly earn that the expanding time to the edge region Can do. Further, the intrusion of the ultraviolet rays of sunlight that adversely affects the durability of the coating and packing can be effectively prevented by the steps as described above.

For this reason, the sealing function of the packing can be maintained over a longer period than before. Therefore, according to this onset bright, the useful life of the casing and or the communication circuitry of the electrical device can be conventionally greatly expanded.
In addition, in order to earn the above-mentioned time longer or to prevent the above-mentioned ultraviolet light from entering more effectively, it is desirable that the above-mentioned step is larger.

In addition , since the distance is provided between the position of the contact surface between the case main body and the lid at the fastening portion or the hinge portion and the slit, the contact surface between the case main body and the lid at the fastening portion or the hinge portion. Thus, it is possible to greatly earn time for the corrosion site based on the crevice corrosion generated from the above to expand into the edge region. For this reason, the sealing function of the packing can be maintained over a longer period than before. Therefore, according to this onset bright, the useful life of the casing and or the communication circuitry of the electrical device can be conventionally greatly expanded.
In order to earn the above time longer, it is desirable that the above distance is longer.

In addition, according to the third means of the present invention, each metal surface is painted and the metal surface is smoothed, so that the case body and the packing, and the lid and the packing are between. The gaps are almost completely eliminated. In addition, since a battery is prevented from being formed on these parts (metal surface) by the non-conductive paint, these parts are well protected from the outside air and the like. Therefore, these synergistic effects further suppress the corrosion of the metal in the vicinity of the packing.

Moreover, according to the 4th means of this invention, corrosion of a metal surface is prevented favorably also by these chemical conversion film processes. In addition, when the above-described coating is performed, the surface treatment is very effective because it brings about an effect that the coating is easy to become familiar with. Therefore, it is more desirable to implement the fourth means in combination with the third means. In that case, the synergistic effect of the third means is further increased.

  The case body and the lid are preferably formed from the same kind of material as possible in order to avoid contact corrosion of dissimilar metals, but even if they are formed using different materials, they are based on the means of the present invention. Thus, it is possible to obtain the functions and effects of the present invention. Usually, an aluminum alloy such as ADCj (j is a natural number) indicated by a JIS symbol is often used as a metal material of a casing of an electric device. For example, ADC1C which is an aluminum alloy containing Al, Cu, Si, Mg, Zn, Fe, Mn, Ni, Sn, Pb, and Ti is an example.

  Of course, the present invention exhibits an excellent function and effect when manufacturing the case body and the lid using any of these aluminum alloys, but the effective scope of the present invention is aluminum. However, the present invention is not limited to the case where the casing (case body or lid) of the electric device is formed of an alloy. For example, even in the case of manufacturing a case using various stainless alloys or any alloy having iron or zinc as a main component as a material, the functions and effects of the present invention are based on the means of the present invention. Can be obtained.

Hereinafter, the present invention will be described based on specific examples.
However, the embodiments of the present invention are not limited to the following examples.

1A and 1B are a plan view (top view) and a side view, respectively, of the casing 100 of the first embodiment. In the first embodiment, to facilitate understanding, the xyz coordinate system is fixedly displayed in the fixed direction shown in FIG. As shown in the figure, this coordinate system is a right-handed three-dimensional orthogonal coordinate system. Further, this coordinate system has nothing to do with the installation form of the housing 100 at the installation site.
The case main body 10 and the lid 20 constituting the casing 100 are both made of an aluminum alloy indicated by JIS symbol “ADC1”. That is, the metal material constituting the casing 100 is mainly composed of aluminum (Al), 11 to 13% silicon (Si), 1.3% or less iron (Fe), and 1% or less copper (Cu). ) And less than 1% zinc (Zn), nickel (Ni), magnesium (Mg), manganese (Mn), and tin (Sn).

  Reference numeral e denotes a ground line, and the case body 10 is grounded by the ground line e. On the other hand, the lid 20 is grounded by making electrical contact with the case body 10. In order to ensure this electrical contact continuously over a long period of time, almost the entire surface of the case body 10 and the lid 20 is subjected to a chemical conversion film treatment. Further, a part of the approaching portion between the case main body 10 and the lid 20 and a portion of the housing 100 that comes into contact with the outside air are provided with a known coating having excellent corrosion resistance. This coating also contributes to ensuring the surface flatness of a part of the contact portion. Moreover, said chemical conversion film process is also contributing to ensuring the durability of this coating.

  In FIG. 2, the front view of the housing | casing 100 of the present Example 1 is shown. The symbol h indicates the slit referred to in claim 3. The slit h is formed over the entire circumference (edge) of the housing 100 in the horizontal direction.

FIG. 3 is a cross-sectional view of a contact portion between the case main body 10 and the lid 20 in the cross section α of the housing 100 illustrated in FIGS. 1A and 2. The first flange 11 included in the case body 10 and the second flange 22 included in the lid 20 are in contact with each other at _two contact surfaces q ₁ and q ₂ on the reference surface σ ₁ . The case body 10 and the lid 20 are kept at the same potential by the general connection. The chemical conversion film treatment described above is for maintaining good electrical connection continuously over a long period of time.

The packing P made of silicon resin is formed in a ring shape, and FIG. 3 shows a cross section thereof. When the lid 20 is opened, the cross-sectional shape of the packing P returns to a substantially isosceles trapezoid shown in the lower right. The storage groove 22a for storing the packing P is provided on the second flange 22 of the lid 20 so as to be concave with respect to the reference plane σ ₁ . Edge) is formed over the entire circumference.

  The above-described coating is applied to the portion of the case main body 10 and the lid 20 that comes into contact with the outside air and the contact portion 12 of the first flange 11 with which the packing P contacts. As a result, the packing pressing surface 12 and the packing P can be adhered sufficiently densely. The width of the air passage S leading from the storage groove 22a to the outside of the housing 100 is secured to about 1 mm at the maximum. The air passage S is bent at an obtuse angle as shown. However, the bent portion may be a right angle. A step described later is formed by this bending.

  The slit h located at the outer front end of the air passage S is formed by a gap between the terrace 11a provided by the first flange 11 and the ceiling surface 21a provided by the ultraviolet reflecting portion 21. The width of the gap between the slits h (the height in the z-axis direction) is secured about 0.5 mm. If this width is too narrow, it is not desirable because water or the like easily enters the air passage S or water stops, and the housing 100 is easily corroded. On the other hand, if the width is too wide, the packing P is likely to be exposed to ultraviolet rays in the environment, and thus the durability of the packing P is impaired.

The step between the terrace 11a and the reference plane σ ₁ is set to about 3 mm. Even with such a level difference setting, it is difficult for the packing P to be exposed to ultraviolet rays, so that the durability of the packing P is improved.
The heights in the z-axis direction of the reference plane σ ₁ , the terrace 11 a, and the ceiling surface 21 a are set to be constant over the entire circumference (edge) of the housing 100 as can be seen from FIGS. ing.

  4A and 4B are a plan view (top view) and a cross-sectional view of the cross section β of the casing 100 of the first embodiment, respectively. This cross section β cuts a fastening portion between the case body 10 and the lid 20 around the bolt 30. An enlarged view of part A of FIG. 4-B is shown in FIG. The vicinity of the packing P has the same structure as that shown in FIG. 3, but this fastening portion centered on the bolt 30 is a fastening mainly formed integrally with the case body 10 (first flange 11). It is comprised from the fastening part 23 formed integrally with the part 13 and the lid | cover 20 (2nd flange 22).

At the contact surface σ ₂ between the fastening portion 13 and the fastening portion 23, the case body 10 and the lid 20 are in surface contact with each other, so that crevice corrosion may occur. However, the contact surface σ ₂ has a step of about 3 mm with respect to the aforementioned reference surface σ ₁ , and is sufficiently away from the packing P, the air passage S, etc. However, it takes a long time to expand widely until the sealing function of the packing P is impaired. Therefore, the sealing function of the packing P can be maintained well over a long period even if crevice corrosion occurs on the contact surface between the fastening portion 13 and the fastening portion 23.

  In addition, when the lid 20 of the casing 100 is opened, dust and dust may adhere to the contact surface between the packing P and the packing pressing surface 12. It is more desirable to take operational considerations such as wiping off. Due to these considerations, the adhesion between the packing P and the packing pressing surface 12 can be maintained higher.

[Other variations]
The embodiment of the present invention is not limited to the above-described embodiment, and other modifications as exemplified below may be made. Even with such modifications and applications, the effects of the present invention can be obtained based on the functions of the present invention.
(Modification 1)
For example, in the above embodiment, the bolt material used for opening / closing and fixing is not particularly mentioned, but at least the surface of the bolt may be formed of the same metal material as the case body or the lid. desirable. Also, it is desirable to carry out chemical conversion film treatment for these bolts and the like.

(Modification 2)
Moreover, between the contact surfaces of the case main body and the lid at the fastening portion or the hinge portion, for example, a thin plate-like ring-shaped resin or rubber having a bolt through hole is provided, and these are sufficiently attached to the case main body and the lid. The gaps between the components may be eliminated as much as possible. Also by such means, the gap formed on the metal surface can be reduced, so that the useful life of the housing can be increased.

(Modification 3)
Further, in the above embodiment, the packing has a substantially trapezoidal cross-sectional shape, but the packing cross-sectional shape is preferably a substantially rectangular shape or a substantially trapezoidal shape with each apex angle of 60 ° or more. If a packing with a substantially circular or elliptical cross-section is used, a gap is easily formed between the packing and the metal surface of the housing (case body or lid). However, the cross-sectional shape of the packing is approximately rectangular or substantially trapezoidal. By doing so, the gaps formed on the metal surface can be reduced, so that the service life of the housing can be increased also by such means.

(Modification 4)
Further, in the above-described embodiment, the shape of the horizontal cross section (cross section perpendicular to the z-axis) of the housing is a substantially rectangular shape, but the shape of such a housing may be arbitrary. This also applies to a cross section in an arbitrary direction. That is, the present invention has arbitraryness with respect to the three-dimensional shape of the entire casing, and the three-dimensional shape is not necessarily limited to a substantially rectangular parallelepiped.

  The present invention is very useful as a means for blocking the inside and the outside of the casing of an electrical apparatus mainly disposed outdoors over time. The effect is particularly great in salt-affected areas along the sea. However, even if the casing of the electrical device of the present invention is placed indoors having a special environment, there are cases in which the operation and effect of the present invention can be greatly entrusted. For example, the present invention can be used by using the case of the present invention indoors or outdoors in a factory that handles chemical substances such as chemicals, in tunnels with a lot of exhaust gas, or indoors with relatively high humidity such as condensation. There are cases in which the actions and effects of can be greatly entrusted.

  In addition, the above-described first embodiment has been devised on the premise that the casing of the wired communication device is exclusively improved. However, if substantially the same application is carried out, the power transmission device and the wireless device arranged outdoors are used. With respect to equipment and the like, it is possible to effectively extend the useful life of the housing or the electrical equipment in a similar manner.

Plan view (top view) of the housing 100 of the first embodiment. Side view of the housing 100 of the first embodiment. The front view of the housing | casing 100 of Example 1. FIG. Sectional drawing of the contact part of case main body 10 and lid 20 in section alpha of case 100 Plan view (top view) of the housing 100 of the first embodiment. Sectional drawing in the cross section (beta) of the housing | casing 100 of Example 1. FIG. Partial enlarged view of FIG. 4-B (: sectional view in section β) Sectional drawing of the contact part of the case main body and cover of the housing | casing of the conventional communication apparatus

DESCRIPTION OF SYMBOLS 100: Case of wired communication apparatus 10: Case main body 11: 1st flange 11a: Terrace 12: Packing contact surface 13: Fastening part (case main body side)
20: Lid 21: Ultraviolet reflecting part 21a: Ceiling surface 22: Second flange 22a: Storage groove 23: Fastening part (lid side)
P: Packing S: ventilation path h: slit sigma _1: reference plane q ₁ in the abutment: the contact surface q ₂ in the reference plane sigma _1: contact surface e of the reference plane sigma _1: ground line

Claims (4)

A metal case body having a first flange formed around the opening, a metal lid having a second flange formed around the opening and contacting the first flange; In a casing of an electric device that can be opened and closed, having an annular packing interposed between a first flange and the second flange,
The first flange and the second flange are in surface contact with the packing on the inner space side of the housing, and a reference surface is configured by the contact surface,
The first flange and the second flange are held in a non-contact manner in an edge region that is an outer region with respect to the packing, and formed around the outer periphery of the edge region. Is formed by a minute gap between a terrace of the case body that is a plane parallel to the reference plane and a ceiling surface of the lid that is a plane parallel to the reference plane, and the terrace and the reference plane Between the slit having a step difference in position in a direction perpendicular to the reference plane, and a communicating portion consisting of a minute interval connecting the slit and a storage groove for storing the packing to constitute the step, An airway consisting of
A first fastening portion integrally formed with the first flange around the outer periphery of the first flange; and a first fastening portion integrally formed with the second flange around the outer periphery of the second flange. A second fastening portion in surface contact with
Have
The reference surface and the contact surface between the first fastening portion and the second fastening portion have a step difference in position in a direction perpendicular to the reference surface with respect to the reference surface. Enclosure of electrical equipment to be used. 2. The electrical equipment casing according to claim 1, wherein a shortest distance between the first flange and the second flange in the edge region is set to 0.1 mm or more and 1 mm or less. A metal surface of the case body that touches the outside air even when the lid is closed;
A metal surface of the lid that touches the outside air even when the lid is closed;
The casing of the electric device according to claim 1 or 2 , wherein both the metal surface of the contact portion that contacts the packing when the lid is closed are painted. The electrical equipment casing according to any one of claims 1 to 3, wherein at least a part of a metal surface inside the casing sealed by the packing is subjected to a chemical conversion film treatment. .

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