JPH0635530Y2 - Planar antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a planar antenna for receiving satellite broadcasting.

[Prior Art] Conventionally, various systems such as a multi-layer system, a patch system, and a crank system have been proposed as a planar antenna of this type for receiving satellite broadcasts. A thin plate cover with good radio wave transmission called a radome is provided on the front side of the, and a back panel (molded product) with a reinforcing plate attached or a reinforcing rib is provided on the back side to withstand wind pressure. Has been.

FIG. 4 shows a multi-layer system in which the ground conductor 10 is also used as the back panel 3 and the feeding circuit board 11 having the feeding circuit pattern formed thereon and the radiation circuit board 12 having the radiation circuit pattern formed thereon are laminated at appropriate intervals. A flat antenna X is shown. The radome 2 is attached to the front side of the flat antenna main body 1, and a waterproof packing 15 is arranged around the joint between the back panel 3 made of the ground conductor 10 and the radome 2 to form a decorative frame 16. It is designed to be pressed down to realize a waterproof mechanism.

FIG. 5 shows another embodiment, in which a patch type planar antenna X is formed by the grounding conductor 10 and the patch circuit board 17, and the radome 2 is covered on the front side of the planar antenna body 1 and molded on the back side. The radome 2 is equipped with a back panel 3 made of products.
After the flanges 2a and 3a provided around the back panel 3 and the back panel 3 are brought into contact with each other and temporarily held by the mounting bracket 18 having a U-shaped cross-section, the waterproof tape 19 is wound around the joint and the outer side is decorated. The bushing 20 is fitted and the appearance is adjusted.

FIG. 6 shows still another conventional example, showing a crank type planar antenna X in which a crank type strip line is formed on the surface of a dielectric substrate 21 having a ground conductor 10a formed on the back surface. The radome 2 is covered on the front side of the antenna body 1, and the back panel 3 made of a molded product is provided on the back side, and the radome 2 and the back panel 3 are sandwiched from the side with a decorative frame 22 having a waterproof function. 22 is fixed by a mounting screw 23 screwed from the side.

[Problems to be Solved by the Invention] However, in the above-described conventional example, since the mechanism for smoothly absorbing the expansion and contraction of the radome 2 does not exist, the radome is caused by temperature rise due to direct sunlight during fine weather. 2 may bulge and adversely affect the reception characteristics, and the radome 2 and the back panel 3
There is a problem that rainwater enters from the abutting part of the peripheral part of the device due to the capillary phenomenon and the reception characteristics are deteriorated. Further, there is a problem that the structure of the joint portion between the radome 2 and the back panel 3 is complicated and the cost becomes high.

The present invention has been made in view of the above points, and an object of the present invention is to prevent the swelling of the radome and the deterioration of the reception characteristic due to the intrusion of rainwater, and the structure is simple and the cost is low. Is to provide a cheap planar antenna.

[Means for Solving the Problems] In the planar antenna of the present invention, a box-shaped radome with an open back surface is attached to the front side of the planar antenna body, and a back panel for reinforcement is provided on the back side of the planar antenna body. Then, a flange having a ridge projecting to the front side over the entire circumference at the center of the radome is provided at the periphery of the opening of the radome, and the flange of the radome is brought into contact with the peripheral portion of the back panel and the contact portion is wrapped. A decorative frame having a C-shaped cross section is fitted and a gap for expansion and contraction is provided between the end of the decorative frame and the peripheral edge of the opening of the radome.

[Operation] The present invention is configured as described above, and has a ridge formed by projecting the central portion over the entire circumference on the front side of the opening edge of the box-shaped radome covered on the front side of the planar antenna body. A flange having is provided, the flange is brought into contact with the peripheral portion of the back panel, and a decorative frame having a C-shaped cross section is fitted so as to wrap around the contact portion, and the end of the decorative frame and the opening peripheral edge of the radome are attached. There is a gap for expansion and contraction between the radome, and because the radome expansion and contraction absorption mechanism is formed by the protrusion provided on the radome flange and the expansion and contraction absorption gap, It is possible to prevent the deterioration of the reception characteristic, and since the projection provided on the flange can prevent the rainwater from entering due to the capillary phenomenon, it is possible to prevent the deterioration of the reception characteristic due to the penetration of the water. Moreover, the configuration Is easy and can be cheaper.

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention.
The front side of the planar antenna body 1 is covered with a box-shaped radome 2 having an open back surface, and a back panel 3 for reinforcement is arranged on the back side of the planar antenna body 1 so that the center portion is entirely covered at the opening periphery of the radome 2. A flange 6 having a ridge portion 5 projecting to the front side over the circumference is provided, and the flange 6 of the radome 2 is brought into contact with the peripheral portion of the back panel 3 and has a C-shaped cross section that encloses the contact portion. The decorative frame 7 is fitted and the above decorative frame 7 is attached.
A gap G for absorbing expansion and contraction is provided between the end of the and the edge of the opening of the radome 2. In the embodiment, the water flip portion 8 is formed by bending the tip of the flange 6 to the back side.
In addition, a reinforcing rib 9 also serving as a waterproof bank is provided on the periphery of the back panel 3, and the rising angle θ of the outer wall 9a of the reinforcing rib 9 is the maximum elevation angle (the maximum elevation angle when receiving in Japan). It is set to be larger than. In the embodiment, the multi-layer type is used as the planar antenna body 1 and the back panel 3 is also used as the ground conductor 10. However, the planar antenna body 1 having another configuration may be used. Needless to say.

The operation of the embodiment will be described below. Now, in the embodiment, the flange 6 having the ridge portion 5 projecting the central portion to the front side over the entire circumference at the opening peripheral edge of the box-shaped radome 2 that is covered on the front side of the planar antenna body 1. Is provided, and the flange 6 is brought into contact with the peripheral portion of the back panel 3, and a decorative frame 7 having a C-shaped cross section is fitted so as to wrap around the contact portion, and the end of the decorative frame 7 and the radome 2 are attached. A gap G for expansion and contraction is provided between the periphery of the opening and the radome 2.
The elasticity of the ridge 5 provided on the flange 6 and the gap G for absorbing expansion and contraction form the expansion and contraction absorbing mechanism of the radome 2.
Even if the temperature of the radome 2 rises due to direct sunlight on a sunny day, the radome 2 does not swell and it is possible to prevent deterioration of the reception characteristics due to swelling of the radome 2. ing. Further, since the projections 5 provided on the flange 6 can prevent rainwater from entering due to a capillary phenomenon, it is possible to prevent deterioration of reception characteristics due to water entering. Further, the joint portion having the waterproof mechanism can be configured only by forming the ridge portion 5 on the flange 6 and fitting the C-shaped decorative frame 7 thereon, and the configuration is simple and the cost can be reduced.

Further, as shown in FIG. 2, the planar antenna X is arranged with an appropriate elevation angle θ ′ so that the receiving surface faces the broadcasting satellite. In the embodiment, the rising angle of the outer wall 9a of the reinforcing rib 9 is set. Since θ is set to the maximum elevation angle or more for the planar antenna X, even if rainwater enters the planar antenna X due to an obstacle in the waterproof structure, the invaded water will not penetrate the outer wall 9a of the reinforcing rib 9. The flat antenna body 1 does not reach the central portion where it is housed and arranged, and does not adversely affect the reception characteristics.

FIG. 3 shows another embodiment in which the peripheral edge of the flange 6 of the radome 2 is folded back to form a water return portion 8a to realize a more reliable waterproofing mechanism.

[Advantages of the Invention] The present invention is configured as described above, and a ridge having a box-shaped radome that is covered on the front side of the planar antenna main body and has a central portion that protrudes to the front side over the entire circumference at the opening peripheral edge. A flange having a portion is provided, the flange is brought into contact with the peripheral portion of the back panel, and a decorative frame having a C-shaped cross section is fitted so as to wrap around the contact portion, and the end of the decorative frame and the opening of the radome. A gap for expansion and contraction is provided between the periphery and the radome expansion and contraction absorption mechanism is formed by the protrusion on the flange of the radome and the expansion and contraction absorption gap. It is possible to prevent the deterioration of reception characteristics due to rising, and since the projections provided on the flange can prevent rainwater from entering due to the capillary phenomenon, it is possible to prevent deterioration of reception characteristics due to water intrusion. You can The effect is that the configuration is simple and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention, FIG. 2 is a sectional view of the same arrangement as above, and FIG. 3 is a sectional view of an essential part of another embodiment,
FIG. 4 is a sectional view of a main part of a conventional example, FIG. 5 is a sectional view of a main part of another conventional example, and FIG. 6 is a sectional view of yet another conventional example. 1 is a planar antenna body, 2 is a radome, 3 is a back panel,
Reference numeral 5 is a protruding portion, 6 is a flange, 7 is a decorative frame, 8 and 8a are water repellent portions, and 9 is a reinforcing rib.

Claims (1)

[Scope of utility model registration request] 1. A planar radome having a box-shaped open rear surface is attached to the front side of the planar antenna main body, a back panel for reinforcement is disposed on the rear side of the planar antenna main body, and a central portion is entirely provided around the opening of the radome. A flange having a ridge protruding to the front side along the circumference is provided, the flange of the radome is brought into contact with the circumference of the back panel, and a decorative frame having a C-shaped cross section that wraps around the contact portion is fitted. A planar antenna having a gap for expansion and contraction between the end of the decorative frame and the peripheral edge of the opening of the radome.