Electrical equipment

Abstract

To prevent damage to the base and cover of electrical equipment at stress concentration points when the internal pressure of the electrical equipment increases. [Solution] The electrical device 1 has a base 2 that houses electrical components and a cover 3 that seals the base 2. A groove 21 is formed on the peripheral edge 20 of the base 2, which can be fitted with a protrusion 31 of the cover 3 via a sealing material 4. Of the inner wall portion 22 and outer wall portion 23 that form the groove 21, the height of the outer wall portion 23 from the bottom of the groove 21 is set lower than the height of the inner wall portion 22 from the bottom.

Description

[Technical Field]

[0001] The present invention relates to a sealing structure for electrical equipment, and particularly to a technique for preventing damage to a base and a cover of electrical equipment caused by a failure of an electrical component mounted on the base of the electrical equipment. [Background Art]

[0002] As a sealing structure that prevents damage to a housing of an electrical device when gas is generated from an electrical component inside the housing, there is the sealing structure for an electrical device disclosed in Patent Document 1. This sealing structure includes: a housing that accommodates an electrical component; a cover that seals the housing; a first attachment portion that fixes the cover; and a second attachment portion having lower attachment strength than the first attachment portion. When the internal pressure of the housing increases due to gas generated when an internal component is damaged, the caulking nut of the second attachment portion comes off, thereby releasing the sealing between the housing and the cover, discharging the gas, and preventing damage to the cover.

[0003] Further, Patent Documents 2 to 4 disclose a sealing structure for an electronic device in which, as illustrated in FIG. 4, a convex portion 31 of a cover 3 is fitted into a groove portion 21 in a peripheral edge portion 20 of a base 2 of an electrical device 1 via a sealing material 4 such as a gasket or packing. Furthermore, Patent Document 5 discloses a sealing structure in which the height of a convex portion of a cover that fits into a groove portion in a peripheral edge portion of a housing of an electronic circuit device differs between the inner peripheral side and the outer peripheral side of the convex portion. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Unexamined Patent Publication No. 2024-122673 [Patent Document 2] Japanese Unexamined Patent Publication No. 09-240717 (Heisei 09) [Patent Document 3] Japanese Patent No. 5983301 [Patent Document 4] Japanese Patent No. 6492983 [Patent Document 5] Japanese Patent No. 4983756 [Overview of the project] [Problems that the invention aims to solve]

[0005] When electrical equipment is installed in environments prone to vibration, such as vehicles, it is required to have high resistance to vibration and shock. Electrical equipment having a crimping structure as described in Patent Document 1 or a fitting structure as described in Patent Documents 2-4 tends to concentrate stress due to vibration and shock in the crimping structure or fitting structure when subjected to such environments.

[0006] Therefore, if an abnormality occurs in the electrical components of an electrical device in the aforementioned environment, causing the internal pressure of the electrical device to rise, it may not be possible to temporarily weaken the fastening force between the base and cover of the electrical device, which could lead to damage to the base and cover.

[0007] In view of the above circumstances, the present invention aims to prevent damage to the base and cover of electrical equipment at stress concentration points when the internal pressure of the electrical equipment rises. [Means for solving the problem]

[0008] One aspect of the present invention is an electrical device comprising a base for mounting electrical components and a cover that seals the base, wherein a groove is formed on the periphery of the base that can be fitted with a protrusion of the cover, and the height of the outer wall portion is set lower than the height of the inner wall portion of the groove portion.

[0009] In one aspect of the present invention, in the electrical equipment, the height of the outer wall portion is equal to or greater than the fitting height of the protrusion portion.

[0010] One aspect of the present invention is an electrical device in which the base comprises a metal material and the cover comprises a resin material.

[0011] One aspect of the present invention is that, in the electrical equipment, the height of the inner side of the outer wall portion is set lower than the height of the inner wall portion, and the height of the outer wall portion decreases from the outside toward the groove portion.

[0012] One aspect of the present invention provides the above electrical device, wherein the electrical component includes a component that generates gas. Effects of the Invention

[0013] According to the present invention described above, it is possible to prevent damage at stress concentration locations of the base and the cover of an electrical device when the internal pressure of the electrical device increases. Brief Description of the Drawings

[0014] [Figure 1] Fig. 1 is a schematic cross-sectional view of a sealing structure for an electrical device according to Embodiment 1 of the present invention. [Figure 2] Fig. 2 is a schematic perspective view of the electrical device according to Embodiment 1. [Figure 3] Fig. 3 is a schematic cross-sectional view of a sealing structure for an electrical device according to Embodiment 2 of the present invention. [Figure 4] Fig. 4 is a schematic cross-sectional view of a sealing structure for an electrical device according to a conventional technique. Mode for Carrying Out the Invention

[0015] Embodiments of the present invention will be described below with reference to the drawings.

[0016] [Embodiment 1] An electrical device 1 to which the sealing structure of Embodiment 1, which is one aspect of the present invention shown in Fig. 1, is applied includes a base 2 of the electrical device 1, and a cover 3 that seals the base 2.

[0017] The base 2 is assumed to have a structure that does not deform due to gas generated when damage occurs, contains a material made of metal (for example, aluminum die-cast), and accommodates electrical components (not shown) of the electrical device 1.

[0018] A groove portion 21 that can be fitted to a convex portion 31 of the cover 3 via a ring-shaped sealing material 4 made of a known elastic member is formed on a peripheral edge portion 20 of the base 2.

[0019] Among an inner wall portion 22 and an outer wall portion 23 that form the groove portion 21, the height of the outer wall portion 23 from the bottom of the groove portion 21 is set to be lower than the height of the inner wall portion 22 from the bottom, and is set to be equal to or greater than the fitting height of the protruding portion 31 of the cover 3.

[0020] The cover 3 is assumed to have a structure that is easily deformed by gas pressure when damage occurs, contains a resin material, and hermetically seals the base 2 accommodating the electrical component.

[0021] A protruding portion 31 that can be fitted into the groove portion 21 of the base 2 via a sealing material 4 is provided on the peripheral edge portion 20 of the cover 3.

[0022] According to the electrical device 1 described above, when the protruding portion 31 of the cover 3 is fitted into the groove portion 21 of the base 2 via the sealing material 4, the base 2 is hermetically sealed by the elastic deformation of the sealing material 4.

[0023] In the groove portion 21, since the height of the outer wall portion 23 from the bottom of the base 2 is lower than the height of the inner wall portion 22 from the bottom, the protruding portion 31 of the cover 3 is easily disengaged from the groove portion 21 by a force directed from the inside of the cover 3 to the outside. Further, since the base 2 is made of a metal material and the cover 3 is made of a resin material, even if gas is generated when the electrical component is damaged and the internal pressure of the base 2 increases, the base 2 does not deform, but the cover 3 can be easily deformed.

[0024] Therefore, when gas is generated from the electrical component that is an internal component of the electrical device 1 due to damage to the electrical component and the internal pressure of the base 2 increases, the protruding portion 31 of the cover 3 disengages from the outer wall portion 23 of the groove portion 21 by the elastic deformation force of the cover 3 toward the outside, enabling the discharge of the gas.

[0025] The height of the outer wall portion 23 from the bottom of the groove portion 21 is set based on the desired internal pressure of the base 2 that allows the gas inside the base 2 to be released. In particular, the height of the outer wall portion 23 from the bottom of the groove portion 21 is set to be greater than or equal to the fitting height of the protrusion 31 of the cover 3. This prevents the protrusion 31 of the cover 3 from unintentionally detaching from the groove portion 21 when it is desired to maintain the internal pressure at a desired value or when the cover 3 deforms due to some external factor and a force is applied to the cover 3 toward the outside of the cover 3.

[0026] As described above, in the electrical equipment 1 of Embodiment 1, the outer wall portion 23 is lower than the inner wall portion 22 in the groove portion 21 of the base 2 that fits with the protrusion 31 of the cover 3. Therefore, when gas is generated due to a malfunction of the electrical components inside the cover 3 and the internal pressure of the base 2 increases, the cover 3 deforms, the protrusion 31 of the cover 3 detaches from the groove portion 21 of the base 2, and the gas is released. Thus, damage to the base 2 and its cover 3 at stress concentration points when the internal pressure of the base 2 of the electrical equipment 1 rises can be prevented. In particular, major damage to the cover 3 can be prevented while maintaining the fastening force of the screws that fix the cover 3 to the base 2.

[0027] [Embodiment 2] As described above, in the sealing structure of Embodiment 1, the height of the outer wall portion 23 of the groove portion 21 is adjusted based on the desired internal pressure of the base 2 that releases the gas inside the base 2. If the outer wall portion 23 of the groove portion 21 is adjusted to be lower than the inner wall portion 22 as in this embodiment, the sealing material 4 may come off the groove portion 21 when it is installed in the groove portion 21. It is also conceivable that the protrusion 31 of the cover 3 may come off the groove portion 21 if the cover 3 is deformed due to external factors.

[0028] Therefore, in the electrical equipment 1 of Embodiment 2 shown in Figure 3, the height of the inner side of the outer wall portion 23 is set lower than the height of the inner wall portion 22 in the groove portion 21, and an inclined surface 231 is formed in which the height of the outer wall portion 23 decreases from the outside toward the groove portion 21. According to this embodiment, the sealant 4 is guided into the groove portion 21 by the inclined surface 231 during the process of attaching the sealant 4 to the groove portion 21, so the ease of attaching the sealant 4 to the groove portion 21 is improved. Furthermore, the unintended detachment of the protrusion 31 of the cover 3 from the groove portion 21 is prevented. Moreover, compared to Embodiment 1, it is easier to hold the cover 3 and adjust the exhaust from the cover 3 in the event of an abnormality in the electrical equipment 1 (when the electrical components are damaged).

[0029] In this embodiment, the outer wall portion 23 only needs to have an inner height lower than the inner wall portion 22. Therefore, the outer height may be set to be the same as or higher than the inner wall portion 22, or it may be formed in a curved, stepped, or other shape, without being limited to an inclined surface 231.

[0030] As described above, according to the sealed structure of the electrical equipment 1 of Embodiment 2, the height of the outer wall portion 23 that forms the groove portion 21 of the base 2 decreases from the outside toward the groove portion 21. Therefore, in addition to the effects of Embodiment 1, the ease of attaching the sealing material 4 is improved compared to Embodiment 1. Furthermore, it is possible to prevent the unintended detachment of the protrusion 31 of the cover 3 from the groove portion 21 of the base 2 due to deformation of the cover 3 caused by external factors. [Explanation of Symbols]

[0031] 1… Electrical equipment 2...base, 20...periphery, 21...groove, 22...inner wall, 23...outer wall, 231...inclined surface 3...cover, 30...periphery, 31...protrusion 4…Sealant

Claims

1. A base for mounting electrical components, A cover that seals the aforementioned base, It has, A groove is formed in the peripheral edge of the base that can be fitted into the protrusion of the cover. An electrical device in which, of the inner wall portion and outer wall portion that form the groove portion, the height of the outer wall portion is lower than the height of the inner wall portion.

2. The electrical equipment according to claim 1, wherein the height of the outer wall portion is greater than or equal to the fitting height of the protrusion portion.

3. The electrical device according to claim 1, wherein the base includes a metal material and the cover includes a resin material.

4. A base for mounting electrical components, A cover that seals the aforementioned base, It has, A groove is formed in the peripheral edge of the base that can be fitted into the protrusion of the cover. An electrical device in which, of the inner and outer wall portions forming the groove, the height of the inner side of the outer wall portion is set lower than the height of the inner wall portion, and the height of the outer wall portion decreases from the outside toward the groove portion.

5. The electrical equipment according to any one of claims 1 to 4, wherein the electrical component includes a component that generates gas.

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