JP2008218946A - Sealing structure of box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve sealability, while reducing the cost and weight using a simple structure, relating to the sealing structure of a box. <P>SOLUTION: A box 9, which has a housing 1 whose an upper surface is opened and a cover 2 which closes the upper surface of the housing 1, is the sealing structure of the box with which the interior is made airtight by sealing a clearance between the housing 1 and the cover 2. The box 9 includes a first guard, which is formed so as to extend in the direction of exterior of a housing 1 from a lower part of an open end in an exterior side 1b of the housing 1, and is provided in an annular shape along the open end; an edge part 4 which is formed so as to extend toward lower place, from an edge end of the cover 2 and toward the center direction of the cover 2, and is provided in an annular shape along the edge end, while being adjacent to the upper surface of the first guard part 5, when the cover 2 is closed; a fastening member 6 which fastens and fixes the cover 2 and the housing 1; and a sealing member 7 which is sandwiched between the open end of the housing 1 and the cover 2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a box seal structure in which an opening on an upper surface of a housing is closed with a lid.

  Conventionally, an electric vehicle that drives a wheel with an electric motor and a hybrid vehicle that uses an engine and an electric motor together to drive a wheel are equipped with an MCU (motor control unit) as an electronic control unit for controlling the operation of the electric motor. ing. Further, even in an automobile not equipped with an electric motor, an ECU (Engine Control Unit) is equipped as an electronic control device that controls fuel injection and ignition timing. Generally, when these electronic control devices are arranged outside the passenger compartment, they are provided inside a sealed box to ensure dustproof and waterproof properties.

  For example, Patent Document 1 discloses a box-shaped structure that houses electronic components such as integrated circuits and power transistors. This box-shaped structure includes a rectangular parallelepiped outer box body having a rectangular opening and an outer box lid for closing the opening, and a ridge on the periphery of the opening of the outer box body. And a concave groove into which a sealing material is fitted is formed in the outer box lid. With these configurations, the protrusions and the concave grooves are fitted together so that the inside of the box-shaped structure can be sealed. The wiring (harness) for the electronic component is connected to the electronic component via a grommet inserted into the notch of the outer box body.

A box having a structure as shown in FIG. 5 has also been developed. The box body 10 is fastened with bolts 14 with a gasket (seal material) 13 sandwiched between the outer box body 11 and the upper lid 12. With such a simple configuration, the gasket 13 can be brought into close contact with the outer box body 11 and the upper lid 12 to improve the dust resistance and waterproofness. It is also known that an O-ring or a liquid sealing material is used instead of the gasket 13 in the box 10 of FIG.
JP 2003-163472 A

  As described above, in the box body 10 in which the sealing material such as the gasket 13 is interposed in the gap between the upper lid 12 and the outer box main body 11, the sealing performance can be improved by increasing the adhesion of the sealing material. However, if the size and the number of the bolts 14 are increased in order to increase the surface pressure acting on the sealing material, the cost and the weight of the entire box 10 also increase. Further, in order to increase the surface pressure while suppressing the increase in the number of bolts 14, it is one idea to increase the plate thickness of the upper lid 12 to increase the rigidity, but an increase in the weight of the entire box 10 is inevitable.

Moreover, if it is going to take the width | variety of a sealing material large, the contact area of the upper cover 12 and the outer case main body 11 must be enlarged. That is, it is necessary to increase the thickness of the outer box body 11 to increase the size or to reduce the internal volume, thereby increasing the cost and the weight of the entire box 10.
The present invention has been devised in view of such a problem, and an object of the present invention is to provide a box sealing structure that can improve sealing performance while reducing cost and weight with a simple configuration. And

  In order to achieve the above object, a box seal structure according to the present invention (Claim 1) includes a casing having a casing having an upper surface opened and a lid for closing the upper surface of the casing. A sealing structure of a box that seals a gap with the lid and seals the inside thereof, and is formed to extend from the lower side of the opening end on the outer side surface of the casing toward the outside of the casing. A first flange portion provided annularly along the end, and extending downward from the edge of the lid toward the center of the lid, and provided annularly along the edge, An edge that contacts the upper surface of the first collar when the lid is closed, a fastening member that fastens and fixes the lid and the housing, and the opening end of the housing and the lid And a sealing member sandwiched between the two.

In addition to the structure of claim 1, the box seal structure of the present invention (Claim 2) is formed to extend outward from the opening end of the housing, and is formed around the opening end. In addition to being provided in a ring shape, a second collar portion that abuts against the back surface of the lid body when the upper surface is closed by the lid body is provided.
In this case, it is preferable that the fastening member fastens the lid and the second flange portion of the casing.

  According to the box seal structure of the present invention (Claim 1), when the lid and the casing are fastened and fixed, the first sealing is performed by the seal member between the opening end of the casing and the lid. A structure can be formed. In addition, the second sealing structure can be formed at the contact portion between the first flange portion and the edge portion, and the sealing performance can be improved. For example, even in a situation where water pressure acts, the second sealing structure prevents water from entering, so that the seal member (first sealing structure) between the opening end of the housing and the lid body is large. Water pressure can be prevented. In addition, since the second sealing structure is positioned below the first sealing structure, even if water enters into the second sealing structure, the second sealing structure gradually Thus, the sealing performance of the first sealing structure can be maintained.

According to the box seal structure of the present invention (Claim 2), the width of the seal member between the open end of the housing and the lid can be increased, and the sealing performance can be further improved. .
Moreover, according to the seal structure of the box of the present invention (Claim 3), the internal volume of the housing can be secured by fastening at the position of the second flange portion. Further, the contact surface pressure between the seal portion and the first flange portion and the edge portion can be easily increased, and the sealing performance can be further improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show a seal structure of a box as one embodiment of the present invention, and FIG. 1 is a longitudinal section showing a configuration of a main part at the time of fastening of a fastening member in a box to which the structure is applied. FIG. 2 is a longitudinal sectional view showing a main part configuration when the fastening member of the book box is not fastened, and FIG. 3 is a perspective view showing the entire structure of the book box. 4A and 4B are longitudinal sectional views for explaining a box seal structure as a modification.

[Constitution]
The box seal structure according to the present invention is applied to a case (box) 9 of an MCU (motor control unit) equipped in an electric vehicle. The MCU is an electronic control device for controlling the behavior of an electric motor mounted on the electric vehicle.
As shown in FIG. 3, the case 9 is a metal box configured with a housing 1 and a lid 2. The housing 1 is formed in a rectangular parallelepiped shape whose upper surface is open, and a predetermined internal volume is ensured therein. An inverter and a controller (not shown) constituting the MCU are accommodated in the housing 1. Hereinafter, the opening formed in the upper surface of the housing 1 is denoted by reference numeral 1a, and the four side surfaces are denoted by reference numeral 1b.

  The opening 1a on the upper surface of the housing 1 and the vicinity of the upper end of the side surface 1b adjacent thereto are closed by a rectangular lid 2 that is slightly larger than the upper surface of the housing 1, and the housing 1 and the lid 2 The gap is sealed (sealed). The lid 2 is composed of a lid body (hereinafter simply referred to as a lid) 2a and an end cover 2b. The lid 2a has a shape that covers the opening 1a and its three sides, and the end cover 2b has a shape that covers the other side along with the overlap with the lid 2a.

FIG. 1 is a longitudinal sectional view of a contact portion between the housing 1 and the lid 2a. On the outer surface 1 b of the housing 1, an upper collar part (second collar part) 5 that extends horizontally from the end of the opening 1 a to the outside and an upper collar part 5 below the upper collar part 5. And a lower collar part (first collar part) 3 extending in parallel with the first and second collar parts.
The upper collar portion 5 is a portion formed by bending the upper end portion of the outer side surface 1b outward, and is formed over the entire circumference around the opening portion 1a. The lower flange 3 is fixed to the side surface 1b of the housing 1 by welding, and is formed over the entire periphery of the opening 1a in the same manner as the upper flange 5. That is, both the upper collar part 5 and the lower collar part 3 are formed in an annular shape along the end of the opening 1a.

On the other hand, an edge portion 4 is formed at the edge of the three sides of the lid 2a. As shown in FIG. 1, the edge part 4 is extended toward the center direction of the lid | cover 2a from the lower end of the 1st edge part 4a extended and formed downward from the edge part of the lid | cover 2a, and the 1st edge part 4a. The second edge portion 4b is formed.
As shown in FIG. 3, a gasket (seal member) 7 is sandwiched between the lid 2 a and the upper collar part 5. A plurality of bolt holes 7a, 5a, and 2c that are arranged in the same manner in a top view are formed in the gasket 7, the upper flange portion 5, and the lid 2a. In FIG. 3, in order to illustrate the bolt hole 5a formed in the upper collar portion 5, a part of the gasket 7 is shown broken away.

  The bolt hole 5a of the upper collar part 5 has a female screw formed on the inner peripheral surface thereof. On the other hand, the inner peripheral surface of the bolt hole 7a of the gasket 7 and the bolt hole 2c of the lid 2a has a cylindrical shape that is not grooved. Thereby, the upper collar part 5, the gasket 7, and the lid | cover 2a can be fastened and fixed using the fastening member 6 which has the external thread screwed together with the internal thread of the bolt hole 5a.

For example, as shown in FIG. 1, a male screw 6a inserted through a bolt hole 2c of the lid 2a and a bolt hole 7a of the gasket 7 is screwed into a bolt hole 5a of the upper collar 5, and a nut 6b is formed from above the lid 2a. The lid 2a and the upper collar part 5 are fastened and fixed.
The shape of the edge 4 is formed so that the lower collar 3 and the second edge 4b come into contact when the upper collar 5 and the lid 2a are fastened and fixed using the fastening member 6 as described above. ing. Further, if the fastening is loosened, as shown in FIG. 2, the lower collar portion 3 and the second edge portion 4b are separated from each other, and a gap d is generated. That is, the gap between the lower collar part 3 and the second edge part 4 b is sealed by fastening the fastening member 6, and the sealing is released by loosening the fastening of the fastening member 6.

  In addition, as shown in FIG. 3, the edge part 4 and the bolt hole 2c are formed also in the edge part cover 2b. The edge 4 of the end cover 2b has substantially the same shape as the edge 4 of the lid 2a, but the thickness of the first edge 4a of the end cover 2b is larger than that of the first edge 4a of the lid 2a. It is formed longer by the minute.

[Action / Effect]
Since the seal structure of the main box is configured as described above, the lid 2 is attached to the housing 1 as follows.

  First, the gasket 7 is mounted on the upper surface of the upper collar portion 5 of the housing 1 while aligning the positions of the bolt holes 5a and 7a. Subsequently, the second edge 4b of the lid 2a is inserted into the groove between the upper collar 5 and the lower collar 3, and the lid 2a is slid in the direction of arrow A shown in FIG. At this time, since a gap of at least d is formed between the lower collar portion 3 and the second edge portion 4b, the lid 2a can be easily moved horizontally.

  Next, the bolt hole 7a of the gasket 7 and the bolt hole 2c of the lid 2a are aligned, and then the end cover 2b is attached so as to cover the end of the lid 2a closest to the arrow A. At this time, the positions of the bolt holes 2c of the end cover 2b and the bolt holes 2c of the lid 2a are matched. Then, the male screw 6a is inserted into the bolt hole 2c and screwed into the bolt hole 5a. As shown in FIG. 2, the lower collar part 3 and the second edge part 4b are not yet in contact at this time, and the gasket 7 is sandwiched between the lid 2a and the upper collar part 5 so that the first sealing is performed. A stop structure is formed.

  Further, the nut 6b is screwed to the male screw 6a and fastened. As a result, as shown in FIG. 1, the gasket 7 is plastically deformed or elastically deformed and is in close contact with the lid 2 a and the upper collar 5. That is, the sealing performance in the first sealing structure is improved. Moreover, the 2nd edge part 4b and the lower collar part 3 contact at this time, and a 2nd sealing structure is formed. That is, the inside of the housing 1 is double-sealed by the first sealing structure and the second sealing structure, and the first sealing structure is protected by the second sealing structure. Will be.

Thereby, for example, even in a situation where water pressure acts from the outside of the housing 1 (when the car is washed, etc.), the second edge 4b and the lower collar 3 prevent water from entering, so that the gasket 7 A large water pressure can be prevented.
In addition, since the second sealing structure is located below the first sealing structure, even if water enters into the second sealing structure, the water gradually becomes the second sealing structure. It is discharged from the sealing structure. Therefore, the sealing performance of the first sealing structure is maintained.

Thus, according to this seal structure, a double sealing structure can be formed with a simple configuration, and the sealing performance can be improved. Further, the number of fastening members 6 can be reduced by the amount of improvement in sealing performance, and the weight and cost of the entire box 10 can be reduced. Alternatively, the width (seal width) of the gasket 7 can be reduced.
In addition, since the double sealing structure does not apply a large water pressure to the first sealing structure, the sealing performance of the first sealing structure can be set lower than in the past at the time of design. Therefore, for example, the plate thickness of the lid 2 can be reduced to reduce the surface pressure acting on the gasket 7. Further, by providing the edge 4 on the lid 2a, the rigidity of the lid 2a itself can be increased, and the surface pressure acting on the gasket 7 can be said to be more advantageous than the conventional structure.

  Moreover, since the arrangement | positioning position of the fastening member 6 is the upper collar part 5 in the housing | casing 1, the thickness of a housing | casing can be made thinner than the conventional box 10 as shown, for example in FIG. . That is, the internal volume can be increased without increasing the size of the housing 1.

[Others]
Although one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the configuration of the above-described embodiment, the upper collar portion 5 formed on the outer surface 1b of the housing 1 is not an essential component. For example, as shown to Fig.4 (a), the bolt hole of the gasket 7 and the fastening member 6 is provided in the upper end surface of the side surface 1b, and the structure which abbreviate | omitted the upper collar part 5 can be considered. That is, the sealing structure is formed on the upper end surface of the side surface 1 b of the housing 1. Even in such a configuration, the second sealing structure can be formed between the second edge portion 4b and the lower flange portion 3, and the same effect as in the above-described embodiment can be obtained.

  Moreover, although the edge part 4 is provided with the 1st edge part 4a and the 2nd edge part 4b in the above-mentioned embodiment, regarding the specific shape of the edge part 4, it is not limited to this. For example, as shown in FIG. 4B, it only has to be formed so as to extend downward from the edge of the lid 2 a and toward the center of the lid 2. In the example of this figure, the edge portion 4 can be easily elastically pressed against the lower collar portion 3, and the sealing performance of the second sealing structure can be further enhanced.

Moreover, in the above-mentioned embodiment, although the external thread 6a and the nut 6b are used as the fastening member 6, you may use the general volt | bolt which has a head and a shaft part instead of this.
In addition, this seal structure can be applied not only as an MCU case of an electric vehicle but also as a seal structure of a case of an ECU or any other electric parts or electronic parts.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view which shows the seal structure of the box as one Embodiment of this invention, and shows the principal part structure at the time of the fastening member in the box to which this structure was applied. It is a longitudinal cross-sectional view which shows the principal part structure at the time of the non-fastening of the fastening member in the box body to which this structure was applied. It is a perspective view which shows the whole structure of the box body to which this structure was applied. It is a longitudinal cross-sectional view for demonstrating the seal structure of the box as a modification, (a) is a structural example without an upper collar part, (b) shows the modification of the shape of an edge part. It is a disassembled perspective view which shows the seal structure of the conventional box.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Lid 3 Lower collar part (1st collar part)
4 Edge 5 Upper collar (second collar)
6 Fastening member 7 Gasket (seal member)
9 box

Claims (3)

In a box having a housing having an upper surface opened and a lid that closes the upper surface of the housing, the box has a sealing structure in which a gap between the housing and the lid is sealed to seal the inside. And
A first brim extending from the lower side of the opening end on the outer surface of the casing toward the outside of the casing and provided in an annular shape along the opening end;
The lid is formed so as to extend downward from the edge of the lid and toward the center of the lid, and is provided in an annular shape along the edge, and contacts the upper surface of the first flange when the lid is closed. Borders that touch,
A fastening member for fastening and fixing the lid and the housing;
A box seal structure, comprising: a seal member sandwiched between the opening end of the casing and the lid. A second flange that is formed to extend outward from the opening end of the housing, is provided in an annular shape around the opening end, and contacts the back surface of the lid when the upper surface is closed by the lid. The box sealing structure according to claim 1, further comprising: The box sealing structure according to claim 2, wherein the fastening member fastens the lid and the second flange portion of the housing.

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