JP2015023223A - Housing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform anticorrosion treatment of a housing by a simpler configuration.SOLUTION: The housing houses an electronic component in the internal space. The housing includes a first member composed of a metal having a passive state film formed on one side, a second member arranged in contact with the one side, and a gel member having self re-adhesion not losing the adhesion even if adhesion is lost once and liquidity. The gel member is arranged to cover at least a part of the outside edge arranged in the outer space, out of the edge of the contact surface in the second member with the first member.

Description

  The present invention relates to a housing that houses electronic components in an internal space.

  Conventionally, in order to suppress corrosion of a metal, it is generally performed to perform an anticorrosion treatment on the surface of the metal by plating. As the anticorrosion treatment by plating, a chromate treatment containing hexavalent chromium or trivalent chromium, a treatment for forming an anticorrosion thin film using zirconium phosphate, so-called zirconium treatment is known.

  Although these treatments have an effect on anticorrosion, the load on the environment is large. In addition, processes and facilities are complicated, and tend to be expensive for management and maintenance. Furthermore, depending on the treatment method, the adhesion of the treated metal surface to the adhesive may be reduced.

  On the other hand, in Patent Document 1, by heating the aluminum alloy vehicle lamp component including at least silicon cast using the die casting method, the silicon on the surface layer of the aluminum alloy vehicle lamp component is oxidized and oxidized. A rust-proofing method for forming a silicon layer has been proposed. Silicon oxide has an antirust effect. This method does not require a large-scale facility as compared with the chromate treatment and the zirconium treatment, and therefore can be reduced in cost. In addition, there is an advantage in that it does not include a material with a large environmental load.

JP 2008-274348 A

  However, even if the method of forming silicon oxide is adopted, it is necessary to contain silicon over the entire portion to be protected from corrosion, and because it requires equipment for heating the silicon, it is compared with the plating process. And dramatic cost reductions cannot be achieved.

  The present invention has been made in view of the above problems, and an object thereof is to perform anticorrosion treatment with a simpler configuration.

  The invention disclosed herein employs the following technical means to achieve the above object. Note that the reference numerals in parentheses described in the claims and in this section indicate a corresponding relationship with specific means described in the embodiments described later as one aspect, and limit the technical scope of the invention. Not what you want.

  In order to achieve the above object, the first member (10) is a housing that houses the electronic component (200) in the internal space (S), and is made of a metal having a passive film (60) formed on one surface thereof. A second member (30) disposed in contact with one surface, and a gel-like member (50) having self-re-adhesion and fluidity that does not lose its adhesion even if the adhesion is once released. A member is arrange | positioned so that at least one part of the outer edge part (40b) arrange | positioned in external space may be covered among the edge parts (40) of a contact surface with the 1st member in a 2nd member. Yes.

  By the way, the corrosion of the metal having a passive film tends to proceed at the edge of the contact surface of another member in contact with the metal. This is because in the pitting corrosion generated near the contact surface between the metal and the member that contacts the metal, the oxygen concentration in the pitting corrosion is lower than the oxygen concentration in the external space. Since the oxygen concentration is low in the pitting corrosion, it becomes difficult to form a passive film again. Further, due to the difference in oxygen concentration between the pitting corrosion and the external space, the vicinity of the pitting corrosion in the metal and the peripheral portion thereof are in a state in which a gas-difference battery is produced, and the corrosion proceeds.

  According to the present invention, when pitting corrosion occurs in the first member, the gel-like member having self-re-adhesiveness enters the generated pitting corrosion. Thereby, the pitting corrosion inner surface of the first member is protected by the gel-like member. Therefore, it can suppress that corrosion progresses to the contact surface with the 2nd member in a 1st member.

It is sectional drawing which shows schematic structure of the housing | casing which concerns on 1st Embodiment. It is an expanded sectional view of the area | region II shown in FIG. FIG. 3 is an enlarged view of a region III shown in FIG. 2 and a cross-sectional view showing the occurrence of pitting corrosion. It is sectional drawing which shows the anticorrosion effect of a gel-like member. It is sectional drawing which shows schematic structure of the housing | casing which concerns on 2nd Embodiment. FIG. 6 is an enlarged sectional view of a region VI shown in FIG. 5.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same reference numerals are given to the same or equivalent parts.

(First embodiment)
Initially, with reference to FIG. 1 and FIG. 2, schematic structure of the housing | casing which concerns on this embodiment is demonstrated.

  As shown in FIG. 1, the housing 100 according to the present embodiment fixes a case 10 having an opening, a cover 20 that covers the opening of the case 10 to form an internal space S, and the case 10 and the cover 20 are fixed. And an adhesive 30 as a fixing member. Furthermore, the housing 100 has a gel-like member 50 so as to cover the edge 40 of the contact surface between the case 10 and the adhesive 30. An electronic component 200 is disposed in the internal space S of the housing 100, and the electronic component 200 is electrically connected to the outside via a connector or the like (not shown).

  This will be described in more detail with reference to FIG. FIG. 2 is an enlarged cross-sectional view of region II shown in FIG.

  The case 10 includes a base portion 12 on which the electronic component 200 is placed, a first wall portion 14 formed integrally with the base portion 12 so as to surround the electronic component 200, and a second wall portion surrounding the first wall portion 14. 16. Thereby, as shown in FIG. 2, a region surrounded by the base portion 12, the first wall portion 14, and the second wall portion 16 constitutes a groove portion 18. In addition, case 10 in this embodiment is a product made from aluminum, for example, can be shape | molded using the die-casting method.

  The cover 20 includes an upper surface portion 22 that faces the base portion 12 of the case 10 and a side surface portion 24 that protrudes perpendicularly from the upper surface portion 22. The cover 20 is disposed so that the side surface portion 24 fits into the groove portion 18 in the case 10. And the internal space S is formed when the upper surface part 22 and the 1st wall part 14 in the cover 10 contact | abut. The cover 20 can also be formed of aluminum.

  The adhesive 30 is, for example, a silicon adhesive and fills the groove 18. More specifically, the adhesive material 30 is filled in the groove 18 to such a depth that the side surface 24 can be sealed from the base 12. As shown in FIG. 2, a part of the side surface 24 in the cover 20 is buried in the adhesive 30 when fitting with the groove 18. As a result, the case 10 and the cover 20 are fixed, and dust and moisture do not enter the internal space S from the outside.

  The adhesive 30 is in contact with the case 10 in the groove 18. The edge 40 on the contact surface between the adhesive 30 and the case 10 has an inner edge 40 a on the inner space side of the housing 10 with respect to the adhesive 30 and an outer edge 40 b on the outer side of the housing 10.

  The gel-like member 50 is, for example, a silicone gel, and is arranged so as to cover the outer edge 40b. Silicone gel is a material having self-re-adhesion and fluidity that does not lose its adhesion even once the adhesion is released. In other words, the silicone gel is a material that can be adsorbed again once it is detached from the case 10 and has fluidity. In the present embodiment, the gel-like member 50 fills a portion surrounded by the second wall portion 16 of the case 10, the side surface portion 24 of the cover 20, and the adhesive 30, thereby covering the outer edge portion 40 b.

  In the above-described embodiment, the first member and the second member described in the claims correspond to the case 10 and the adhesive 30, respectively.

  Next, with reference to FIG. 3 and FIG. 4, the effect of the housing | casing 10 which concerns on this embodiment, mainly the gel-like member 50 is demonstrated.

  FIG. 3 is an enlarged cross-sectional view of region III shown in FIG. As described above, the case 10 is made of aluminum. Aluminum is one of valve metals, and as shown in FIG. 3, a passive film 60 is formed on the surface of the case 10. For this reason, the surface of the case 10 is in a state where it is difficult to corrode.

However, when the passive film 60 is broken by halogen ions or the like outside the housing 10 and aluminum is exposed, pitting corrosion 70 is generated by oxygen dissolved in the surrounding moisture. The chemical reaction formula at this time is
Al + 3 / 4O ₂ + 3 / 2H ₂ O → Al ³⁺ + 3OH ⁻ → Al (OH) ₃
It is. By this reaction, oxygen is deficient in the vicinity of the pitting corrosion 70. For this reason, in the case 10, a ventilation battery is induced between the vicinity of the pitting corrosion 70 and a position away from the pitting corrosion 70. That is, at a position away from the pitting corrosion 70,
Cathode reaction: O ₂ + 2H ₂ O + 4e ⁻ → 4OH ⁻
Happens. At the same time, in the vicinity of pitting corrosion 70,
Anode reaction: Al → Al ³⁺ + 3e ⁻
Happens.

Furthermore, hydrolysis reaction is caused by the generated aluminum ions and moisture: Al ³⁺ + 3H ₂ O → Al (OH) ₃ + 3H ⁺
Happens. By this hydrolysis reaction, the hydrogen ion concentration in the vicinity of the pitting corrosion 70 increases, and the pH decreases. Aluminum is less prone to passivation and is susceptible to corrosion in an acidic environment with a pH of less than 4. For this reason, the corrosion proceeds with the occurrence of the pitting corrosion 70. In particular, corrosion tends to proceed directly under the adhesive 30 where the oxygen concentration tends to be low.

  On the other hand, the housing 100 according to the present embodiment includes a gel-like member 50 having self-re-adhesiveness and fluidity as shown in FIGS. 3 and 4. For this reason, even if the pitting corrosion 70 occurs in the case 10, as shown in FIG. 4, the gel-like member 50 flows and enters the pitting corrosion 70, and comes into close contact with the surface of the case 10. Thereby, the progress of the various reactions described above can be suppressed on the aluminum surface. Therefore, the progress of corrosion can be suppressed.

  Note that, as described above, when the pH is lowered by the hydrolysis reaction, since it is difficult for aluminum to form the passive film 60, corrosion tends to proceed. Therefore, in order to suppress acidification in the vicinity of the pitting corrosion 70, the gel-like member 50 is preferably made alkaline. Specifically, sodium hydroxide or potassium hydroxide is mixed with silicone gel to make it alkaline. Aluminum is susceptible to corrosion in an environment having a pH of less than 4 or greater than 9. For this reason, as content of sodium hydroxide or potassium hydroxide, it is good to adjust so that pH inside pitting 70 may become 4 or more and 9 or less by the penetration of gel-like member 50.

  Moreover, the manufacturing method of the housing | casing 100 which concerns on this embodiment is a simple thing which apply | coats the gel-like member 50, after attaching the cover 20 to the case 10 conventionally. For this reason, the cost reduction can be realized not only in comparison with chromate treatment and zirconium treatment, but also in comparison with rust prevention by silicon oxide.

(First modification)
In the above-described embodiment, the example in which the first member and the second member described in the claims correspond to the case 10 and the adhesive material 30, respectively, has been described. That is, the example which paid attention to the corrosion in the edge part 40 vicinity of the contact surface of case 10 and the adhesive material 30 was shown.

  On the other hand, even if the first member and the second member described in the claims correspond to the cover 20 and the adhesive 30, respectively, the same effects can be obtained. In the above embodiment, the cover 20 is also made of aluminum, and corrosion can occur near the outer edge 40c of the contact surface between the cover 20 and the adhesive 30 as shown in FIG. On the other hand, the gel-like member 50 is arrange | positioned so that the applicable outer edge part 40c may be covered. Therefore, with the same configuration as that of the first embodiment, it is possible to achieve an effect on the corrosion of the cover 20.

(Second Embodiment)
In 1st Embodiment, the case 10 and the cover 20 showed the example fixed without the contact in the groove part 18 with the adhesive material 30 as a fixing member. In contrast, in the present embodiment, as shown in FIG. 5, an example will be described in which the cover 20 is fixed in contact with the case 10 by a screw 80 as a fixing member.

  As shown in FIG. 5, the case 10 and the cover 20 are arranged such that the peripheral edge portions of the opposing surfaces are in contact with each other and the contact surfaces surround the electronic component 200. And in the peripheral part which the case 10 and the cover 20 contacted, each other is being fixed with the screw 80. FIG. A central portion surrounded by the peripheral edge portion forms an internal space S.

  When the first member described in the claims is regarded as the case 10 and the second member is regarded as the cover 20, the gel-like member 50 covers the outer edges 42 of the contact surfaces as shown in FIG. Are arranged as follows. Thereby, when pitting corrosion occurs in the vicinity of the outer edge 42 in the case 10, the gel-like member 50 enters the pitting corrosion, and further progress of corrosion can be suppressed. FIG. 6 is an enlarged cross-sectional view of the region VI shown in FIG.

  Further, even when the first member described in the claims is regarded as the cover 20 and the second member is regarded as the case 10, the same effect can be obtained. That is, when pitting corrosion occurs in the vicinity of the outer edge portion 42 of the cover 20, the gel-like member 50 enters the pitting corrosion, and further progress of corrosion can be suppressed.

  Furthermore, when the gel-like member 50 regards the first member described in the claims as the cover 20 and the second member as the screw 80, as shown in FIG. It is arranged to cover. Thereby, when pitting corrosion arises in the outer edge part 44 vicinity in the cover 20, the gel-like member 50 approachs into this pitting corrosion, and the progress of the further corrosion can be suppressed.

  The same applies to the case where the first member described in the claims is regarded as the screw 80 and the second member is regarded as the cover 20. In the case where pitting corrosion occurs in the vicinity of the outer edge 44 of the screw 80. The gel-like member 50 enters the pitting corrosion, and the progress of further corrosion can be suppressed.

(Other embodiments)
The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In 2nd Embodiment, the case 10 and the cover 20 showed the example fixed using the screw 80 as a fixing member, However, It is not limited to this example. For example, the present invention can be applied even when the case 10 and the cover 20 are fixed by snap fitting. That is, in the case where pitting corrosion occurs in the case 10 or the cover 20 by arranging the gel-like member 50 so as to cover the outer edge portion of the contact surface between the case 10 and the cover 20, the same as in the second embodiment. , The progress of corrosion can be suppressed.

  Moreover, in each above-mentioned embodiment, although aluminum which the passive film 60 produced was mentioned as an example as a 1st member, if it is valve metals, such as chromium and titanium, this invention is applicable.

DESCRIPTION OF SYMBOLS 100 ... Case 10 ... Case 20 ... Cover 30 ... Adhesive 40 ... Edge part, 40b, 40c, 42, 44 ... Outer edge part 50 ... Gel-like member 60 ... Passive film 70 ... Pitting corrosion 80 ... Screw

Claims (12)

A housing that houses the electronic component (200) in the internal space (S),
A first member (10) made of metal having a passive film (60) formed on one surface;
A second member (30) disposed in contact with the one surface;
A gel-like member (50) having self-re-adhesion and fluidity that does not lose its adhesion even if the adhesion is once released,
The gel-like member is arranged so as to cover at least a part of the outer edge (40b) arranged in the external space among the edge (40) of the contact surface of the second member with the first member. A housing characterized by that. A case (10) having an opening;
A cover (20) as the first member fixed to the case and covering the opening so as to form the internal space;
The housing according to claim 1, further comprising: a fixing member (30) as the second member that fixes the case and the cover to each other. A case as the first member having an opening;
A cover fixed to the case and covering the opening so as to form the internal space;
The housing according to claim 1, further comprising: a fixing member as the second member that fixes the case and the cover to each other. A case as the second member having an opening;
A cover as the first member fixed to the case and covering the opening so as to form the internal space;
The housing according to claim 1, further comprising a fixing member that fixes the case and the cover to each other. A case as the first member having an opening;
A cover as the second member fixed to the case and covering the opening so as to form the internal space;
The housing according to claim 1, further comprising a fixing member that fixes the case and the cover to each other. A case having an opening;
A cover as the second member fixed to the case and covering the opening so as to form the internal space;
The casing according to claim 1, further comprising a fixing member as the first member that fixes the case and the cover to each other.   The case according to claim 2, wherein the fixing member is an adhesive, and is interposed between the case and the cover.   The case according to claim 1, wherein the first member is made of an aluminum-based material.   The casing according to claim 1, wherein the gel-like member is a silicone gel.   The casing according to claim 1, wherein the gel-like member is alkaline.   The casing according to claim 10, wherein the gel-like member contains potassium hydroxide or sodium hydroxide. The first member is mainly composed of aluminum;
The alkalinity of the gel-like member is adjusted so that the pH of the portion where the first member and moisture contact to cause a hydrolysis reaction is 4 or more and 9 or less by contacting the gel-like member. The housing according to claim 10 or 11, characterized in that

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