Waterproof case

Abstract

To provide a waterproof case for which the waterproof of a hole through which a wire harness passes is improved.SOLUTION: A waterproof case disclosed in this specification includes a case body that houses an electric device, a foam sheet, and a waterproof grommet. The case body is provided with a hole through which a wire harness connected to the electric device passes. The foam sheet is arranged on an outer surface of the case body so as to surround the hole. The wire harness passes through the waterproof grommet, and the waterproof grommet fits into the hole while being in contact with the foam sheet. By sandwiching the foam sheet between an outer plate of the case body and the waterproof grommet, the waterproofness of the hole through which the wire harness passes is improved.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a waterproof case that houses an electrical device to which a wire harness is connected. [Background technology]

[0002] Patent Document 1 discloses a case that houses electrical equipment. The case houses a fuel cell stack and a voltage converter, and is mounted on the vehicle. A power cable (wire harness) is connected to the fuel cell stack and the converter, and the power cable passes through the case. A seal structure is used to seal the space between the power cable and the case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-254174 A Summary of the Invention [Problem to be solved by the invention]

[0004] A specific sealing structure is not disclosed in Patent Document 1. This specification provides a technique for improving the waterproofness of a hole in a waterproof case through which a wire harness passes. [Means for solving the problem]

[0005] The waterproof case disclosed in this specification is for housing an electrical device. Metal The case includes a case body, a foam sheet, and a waterproof grommet. The case body has a hole through which a wire harness connected to an electrical device passes. The foam sheet is attached to the outer surface of the case body so as to surround the hole. pasting The wire harness passes through the waterproof grommet, which is fitted into the hole while being in contact with the foam sheet. More specifically, a groove is provided on the outer periphery of the waterproof grommet, and the edge of the hole in the case body and the foam sheet fit into the groove. Furthermore, of the inner surfaces on both sides of the groove, lips are provided on the sides that come into contact with the foam sheet, protruding toward the foam sheet, and the lips are pressed against the foam sheet.

[0006] The waterproof case disclosed in this specification improves the waterproofness of the hole through which the wire harness passes by sandwiching a foam sheet between the outer surface of the case body and the waterproof grommet. Details and further improvements of the technology disclosed in this specification will be described in the "Description of Embodiments" below. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of the waterproof case according to the embodiment. [Diagram 2] This is a diagram of the case body with the grommets and foam sheet removed. [Diagram 3] 1 is a front view of an outer surface 11 of a case main body. [Figure 4] 4 is a cross-sectional view of the waterproof case taken along line IV-IV in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A waterproof case 2 according to an embodiment will be described with reference to the drawings. FIG. 1 shows a perspective view of the waterproof case 2. The waterproof case 2 has a case body 10 and a cover that covers the upper surface of the case body 10, but the cover is not shown in FIG. 1. FIG. 2 shows a perspective view of the case body 10 with the foam sheet 5 and waterproof grommet 20 removed. The cover is attached to a flange 14 provided around the upper opening of the case body 10. A gasket is sandwiched between the flange 14 and the cover to ensure waterproofing. In FIGS. 1 and 2 (and FIGS. 3 and 4 described below), the foam sheet 5 is hatched in gray to aid understanding.

[0009] A computer 3 is housed in the waterproof case 2. The waterproof case 2 is mounted on an electric vehicle. The computer 3 housed in the waterproof case 2 is an electric device that controls the motor of the electric vehicle and the like. A wire harness 4 that bundles together a communication cable, a power cable, and the like is connected to the computer 3. The communication cable and the power cable are connected to devices outside the waterproof case 2. For this reason, a hole 12 is provided on the outer surface 11 (side surface) of the case body 10, and the wire harness 4 extends from inside the case body 10 to the outside through the hole 12. In Figures 1 and 2, illustration of the device connected to the end of the wire harness 4 is omitted.

[0010] The waterproof structure of the gap between the hole 12 and the wire harness 4 will be described. A foam sheet 5 is attached to the outer surface 11 of the case body 10 so as to surround the hole 12. The foam sheet 5 is provided with a hole (sheet hole 5a) of the same size as the hole 12. A waterproof grommet 20 is fitted into the hole 12, and the wire harness 4 passes through a central hole of the waterproof grommet 20. In other words, the waterproof grommet 20 fills the gap between the hole 12 and the wire harness 4. The waterproof grommet 20 is fitted into the hole 12 while being in contact with the foam sheet 5.

[0011] FIG. 3 shows the case body 10 when the outer surface 11 is viewed from the front. The outer surface 11 is a horizontally long rectangle with a height HL shorter than a width WL. The hole 12 provided in the outer surface 11 is a horizontally long oval. As shown in FIG. 3, the foam sheet 5 is larger than the outline of the waterproof grommet 20.

[0012] Fig. 4 shows a cross section of the waterproof case 2 taken along line IV-IV in Fig. 3. Fig. 4 shows a cross section taken along a plane passing through the center of the waterproof grommet 20. The waterproof grommet 20 is made of rubber. The wire harness 4 passes through a central hole 21 of the waterproof grommet 20. A plurality of lips 24 are provided on the inner periphery of the central hole 21. The multiple lips 24 come into contact with the wire harness 4, improving the waterproofing of the central hole 21.

[0013] A groove 22 is provided on the outer periphery of the waterproof grommet 20. An enlarged view of the periphery of the groove 22 is shown in the upper right of Fig. 4. To facilitate understanding, the case body 10 and the foam sheet 5 are drawn by imaginary lines in the enlarged view.

[0014] The edge of hole 12 in outer surface 11 and the edge of sheet hole 5a in foamed sheet 5 fit into groove 22. Of the inner surfaces on both sides of groove 22, a lip 23 protruding toward foamed sheet 5 is provided on the side in contact with foamed sheet 5.

[0015] The lip 23 is pressed firmly against the foam sheet 5, thereby improving the waterproofing of the hole 12. In particular, since the foam sheet 5 is made of a material softer than the case body 10, when the lip 23 of the waterproof grommet 20 is pressed firmly against it, both the lip 23 and the foam sheet 5 are deformed, increasing the degree of adhesion and improving the waterproofing. It is desirable that the lip 23 and the foam sheet 5 have the same degree of softness.

[0016] The foam sheet 5 is made of porous rubber. The foam sheet 5 is of a closed cell type, and the multiple holes inside are independent of each other. Since the foam sheet 5 is of a closed cell type, moisture does not penetrate into the inside of the case body 10 through the foam sheet 5.

[0017] The waterproof case 2 has the following features and advantages. A hole 12 through which the wire harness 4 passes is provided on the outer surface 11 of the case body 10. A foam sheet 5 is arranged on the outer surface 11 so as to surround the hole 12. A waterproof grommet 20 is fitted into the hole 12 while contacting the foam sheet 5. The wire harness 4 passes through a central hole 21 of the waterproof grommet 20.

[0018] The case body 10 is made of metal such as aluminum. A foam sheet 5 is attached to the outer surface 11 of the aluminum, and a lip 23 of a waterproof grommet 20 is pressed against the surface of the foam sheet 5. By sandwiching the foam sheet 5 between the outer surface 11 and the waterproof grommet 20, the waterproofness between the hole 12 and the waterproof grommet 20 is improved compared to when the lip 23 is pressed directly against the metallic outer surface 11.

[0019] As shown in Fig. 3, the hole 12 provided in the case body 10 is elliptical. The waterproof grommet 20 is also elliptical to match the elliptical hole 12. In the long axis direction of the ellipse (Y direction of the coordinate system in the figure), a large volume can be allocated to the waterproof grommet 20, so the waterproofness of the hole 12 and the waterproof grommet 20 is high. On the other hand, in the short axis direction (Z axis direction of the coordinate system in the figure), since the height HL of the case body 10 is short, a large volume cannot be allocated to the waterproof grommet 20, so the waterproofness is inferior compared to the long axis direction. However, by disposing the foam sheet 5, the waterproofness in the short axis direction is also improved.

[0020] A method for attaching the foam sheet 5 will be briefly described. The foam sheet 5 is attached to the outer surface 11 of the case body 10 before attaching the waterproof grommet 20. The foam sheet 5 is attached to the periphery of the hole 12 with a stamp-shaped tool. The foam sheet 5 is attached to the outer surface 11 with an adhesive. It is sufficient that the adhesive is applied to the edge of the hole 12 on the outer surface 11, and it is not necessary to apply the adhesive near the outer peripheral edge of the foam sheet 5.

[0021] The foam sheet 5 is provided in advance with an elliptical hole (sheet hole 5a) of the same size as the hole 12 of the case body 10. A tab is provided on the edge in the short axis direction of the elliptical sheet hole 5a. The tab is provided on the edge on the side closer to the flange 14 of the case body 10. By pulling the tab before attaching the foam sheet 5 to the case body 10, interference between the foam sheet 5 and the flange 14 can be prevented. After the foam sheet 5 is attached to the case body 10, the tab is cut off.

[0022] The following points should be noted regarding the technology described in the embodiment. The shape of the waterproof case is not limited to a rectangular parallelepiped. The computer 3 in the embodiment corresponds to an example of an electrical device that can be accommodated in the waterproof case. The electrical device that can be accommodated in the waterproof case is not limited to a computer.

[0023] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0024] 2: Waterproof case 3: Computer 4: Wire harness 5: Foam sheet 10: Case body 11: Outer surface 12: Hole 14: Flange 20: Waterproof grommet 21: Center hole 22: Groove 23, 24: Lip

Claims

1. A waterproof case for accommodating an electrical device to which a wire harness is connected, a metal case body that houses the electrical device; a hole provided in the case body through which the wire harness passes; a foam sheet attached to an outer surface of the case body so as to surround the hole; a waterproof grommet through which the wire harness passes and which is fitted into the hole while being in contact with the foam sheet; Equipped with A groove is provided on the outer periphery of the waterproof grommet, and the edge of the hole of the case body and the foam sheet are fitted into the groove, A waterproof case in which a lip protruding toward the foam sheet is provided on the inner surface of both sides of the groove that contacts the foam sheet, and the lip is pressed against the foam sheet.

2. 2. The waterproof case according to claim 1, wherein the foam sheet is of a closed cell type.

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