JP4334265B2 - Electric wave leakage prevention structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure in which an opening of a housing is hermetically sealed by a lid so as not to leak radio waves, and is used, for example, in a satellite broadcast / satellite communication reception converter (LNB).
[0002]
[Prior art]
In a conventional satellite broadcast / satellite communication receiving converter (LNB), as shown in FIG. 4, a casing d having a groove c having an inner piece a and an outer piece b at the upper peripheral edge, A lid f on which a rib e that can be inserted into the groove c is erected. The rib e of the lid f is inserted into the groove c of the housing d so that the upper surface opening of the housing f is the lid. In addition to being blocked by f, a sealing agent g was provided in the groove c, and the rib e was sealed in the groove c.
[0003]
Conventionally, the space between the rib e and the groove c is hermetically sealed by the sealing agent g filled in the groove c, and the space closed by the housing d and the lid f is kept airtight.
[0004]
[Problems to be solved by the invention]
However, in the structure in which the sealing agent g is kept airtight as in the conventional case, since there are few portions where the casing d and the lid f are in close contact with each other, radio waves pass through the layer of the sealing agent g and radio wave leakage occurs. There was an inconvenience that the amount became large.
[0005]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a radio wave leakage prevention structure that can maintain airtightness and can prevent radio wave leakage.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the radio wave leakage prevention structure of the present invention includes a casing in which a groove portion having an inner piece and an outer piece is formed at the upper peripheral edge, and a lid provided with a rib that can be inserted into the groove portion. And the rib portion of the lid is inserted into the groove portion of the housing, and the upper surface opening of the housing is closed by the lid body, and a sealing agent is provided in the groove portion so that the rib is sealed in the groove portion. In this structure, an intermediate groove portion is formed in the groove portion, and the tip end portion of the rib of the lid is fitted and adhered to the intermediate groove portion . Since the degree of close contact between the lid and the housing is increased by this fitting and close contact, it is difficult for radio waves to leak directly into the sealant layer.
[0007]
Moreover, the inner lid | cover which closely_contact | adheres to this inner side piece and a cover body may be provided between the inner piece and lid body of the upper-end peripheral part of a housing | casing . In this case, the gap between the inner piece of the casing and the lid is sealed by the inner lid, and the degree of adhesion between the lid and the casing is increased due to the close contact between the middle groove and the tip of the rib. As a result, radio waves are more difficult to leak.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 shows a reference example of a radio wave leakage prevention structure of a satellite broadcast / satellite communication reception converter (LNB).
[0011]
This radio wave leakage prevention structure is a structure in which the housing 1 and the lid 2 are sealed with a sealing agent 3, and the inner piece between the inner piece 11 and the lid 2 at the upper peripheral edge of the housing 1. An inner lid 4 that is in close contact with the lid 11 and the lid 2 is provided.
[0012]
The housing 1 is configured to accommodate the substrate unit 10 therein. A groove 13 having an inner piece 11 and an outer piece 12 is formed at the upper peripheral edge of the housing 1. The inner piece 11 is formed higher than the outer piece 12.
[0013]
The lid 2 is provided with ribs 21 standing on the outer peripheral edge thereof, and the ribs 21 are formed to have a height and thickness to be inserted into the groove 13 of the housing 1.
[0014]
The sealing agent 3 is provided in the groove 13 of the housing 1. As this sealing agent 3, what was made to harden | cure to the state which has elasticity is used after passing curing time after providing in the groove part 13. FIG. After the sealing agent 3 is provided in the groove 13 of the housing 1, the portion of the rib 21 of the lid 2 is inserted into the groove 13 of the housing 1, so that the airtightness between the groove 13 and the rib 21 is increased. The casing 1 and the lid body 2 can be combined in a sealed state.
[0015]
The inner lid 4 is formed in a sheet shape having elasticity that fits inside a rib 21 erected on the periphery of the lid body 2. The inner lid 4 is formed by inserting the rib 21 portion of the lid body 2 into the groove 13 of the housing 1 and sealing the housing 1 and the lid body 2 together with the inner piece 11 and the lid body 2 of the housing. Those formed to a thickness capable of filling the gaps are used.
[0016]
According to the radio wave leakage prevention structure using the inner lid 4, the gap between the housing 1 and the lid body 2 is filled by the inner lid 4, so that it is difficult for radio waves to leak directly into the layer of the sealing agent 3.
[0017]
Figure 2 shows an implementation in the form of a radio wave leakage preventing structure of the present invention.
[0018]
In this radio wave leakage prevention structure, an intermediate groove portion 14 is formed in the groove portion 13 of the housing 1, and the end portions 21 a of the ribs 21 of the lid body 2 are fitted and adhered to the intermediate groove portion 14.
[0019]
The middle groove portion 14 is formed on the bottom surface of the groove portion 13, and the tip portion 21 a of the rib 21 must be fitted and adhered. In this case, if the middle groove portion 14 is formed deeply, the tip portion 21a of the rib 21 can be deeply fitted and brought into close contact, but the casing 1 is required to have a thickness and processing accuracy sufficient to form the middle groove portion 14 deeply. The Moreover, when the middle groove part 14 is formed shallowly, there is a concern that the fitting contact of the tip part 21a of the rib 21 becomes insufficient. Accordingly, the depth of the middle groove portion 14 is determined to a depth that allows the rib 21 to be securely fitted and adhered within a range where it is not as deep as possible. The depth of the middle groove portion 14 is appropriately changed depending on the material and size of the housing 1 and the lid body 2 and cannot be described. However, in the present embodiment, the overall height of the rib 21 is not described. About 1/4 of the tip 21a is formed so as to be fitted and adhered to the middle groove 14. The front end 21a of the rib 21 of the lid 2 is fitted and brought into close contact with the middle groove portion 14 of the casing 1, thereby increasing the degree of adhesion between the casing 1 and the lid 2, so that radio waves are directly applied to the layer of the sealing agent 3. It becomes difficult to leak.
[0020]
It should be noted that at least one of the rib 21 and the middle groove portion 14 may be tapered so that the tip 21a of the rib 21 and the middle groove portion 14 can be easily fitted and adhered.
[0021]
Moreover, the inner lid 4 shown in FIG. 1 may be used in combination with the radio wave leakage prevention structure shown in FIG. In this case, the end portion 21a of the rib 21 and the middle groove portion 14 are fitted and brought into close contact with each other, so that the degree of close contact between the housing 1 and the lid 2 is increased, and the housing 1 and the lid are also connected through the inner lid 4. Since the degree of close contact with the body 2 is increased, it is possible to further prevent radio waves from leaking.
[0022]
FIG. 3 shows still another reference example of the radio wave leakage prevention structure of the present invention.
[0023]
This radio wave leakage prevention structure is formed as an abutting portion 21b having an L-shaped cross section in which the tip end portion of the rib 21 of the lid body 2 is bent in a direction perpendicular to the standing direction of the rib 21, and this abutting portion 21b. Is in contact with and in close contact with the bottom surface in the groove 13 of the housing 1.
[0024]
The contact portion 21b is bent in a direction orthogonal to the direction in which the rib 21 is erected, so that the rib 21 has an L-shaped cross section, and the contact portion 21b is formed on the bottom surface of the groove portion 13 of the housing 1. 21b must be in close contact. Therefore, the contact portion 21 b is formed so as to be within the range of the groove width of the groove portion 13. When the contact portion 21b is in close contact with the bottom surface of the groove portion 13, the degree of close contact between the housing 1 and the lid body 2 is increased, and radio waves are less likely to leak directly into the layer of the sealant 3.
[0025]
Further, the inner lid 4 shown in FIG. 1 may be used in combination with the radio wave leakage prevention structure shown in FIG. In this case, the contact portion 21b of the rib 21 and the bottom surface of the groove portion 13 are fitted and brought into close contact with each other, so that the degree of close contact between the housing 1 and the lid body 2 is increased, and the housing 1 is also provided through the inner lid 4. Since the adhesion between the lid 2 and the lid 2 is increased, it is possible to further prevent radio waves from leaking.
[0026]
2 and 3, the same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.
[0027]
【The invention's effect】
As described above, according to the present invention, since the portion where the housing and the lid are in close contact with each other is increased, the airtightness is increased, and it is possible to further prevent radio wave leakage.
[Brief description of the drawings]
FIG. 1A is a front view of a housing portion of a satellite broadcasting / sanitary communication receiving converter which is a reference example of a radio wave leakage preventing structure according to the present invention, and FIG. 1B is a sectional view taken along line II of FIG. Line sectional drawing, (c) is the principal part enlarged view of the figure (b).
FIG. 2 is an enlarged view of a main part showing another embodiment of a housing portion of a satellite broadcasting / sanitary communication receiving converter which is an example of a radio wave leakage preventing structure according to the present invention.
3 is a further enlarged view showing the casing portion of satellite and sanitation communication reception converter which is another reference example of a radio wave leakage prevention structure according to the present invention.
4A is a plan view showing a housing portion of a conventional satellite broadcasting / satellite communication receiving converter, FIG. 4B is a sectional view taken along line IV-IV in FIG. 4A, and FIG. It is a principal part enlarged view of (b).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing | casing 11 Inner piece 12 Outer piece 13 Groove part 14 Middle groove part 2 Lid body 21 Rib 21a Tip part 21b Contact part 3 Sealing agent 4 Middle cover

Claims (2)

A housing in which a groove portion having an inner piece and an outer piece is formed at the upper peripheral edge portion, and a lid body in which a rib that can be inserted into the groove portion is erected,
The structure is such that the rib portion of the lid is inserted into the groove portion of the housing so that the upper surface opening of the housing is closed by the lid, and the sealing portion is provided in the groove and the rib is sealed in the groove. And
A radio wave leakage prevention structure characterized in that a middle groove portion is formed in the groove portion, and a leading end portion of a rib of a lid is fitted and adhered to the middle groove portion . The radio wave leakage prevention structure according to claim 1, wherein an inner lid that is in close contact with the inner piece and the lid is provided between the inner piece and the lid at the upper peripheral edge of the casing .

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