JPH04115704A - Reflector for parabolic antenna - Google Patents

Abstract

PURPOSE:To prevent deformation of a reflector parabolic face when the reflector is fixed to a mount device and to make the mount device compact by arranging a fixed part of the mount device at the rear side of the reflector to three points in a triangle shape. CONSTITUTION:A fixing boss 2 is arranged to three points in a triangle shape. The share of a wind pressure load per one fixed boss is equalized through the arrangement of the bosses 2 in this way. Furthermore, the boss at the upper one point is fitted tentatively to the mount device by using a bolt, then the hole position of the boss and the mount device at the lower two points is matched naturally by the self-weight of the reflector and the mount is facilitated. Moreover, the reference plane formed by the upper face of the bosses 2 at the three points is easily obtained and the mount device is made compact.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a reflector for a parabolic antenna that receives radio waves from a broadcasting satellite or a communication satellite. This relates to the fixing part of the mounting device.

[Conventional technology]

Currently, the mainstream reflector for parabolic antennas for satellite broadcasting reception is the 45 type (opening diameter 450 mm), which is fixed to the mounting device with four fixing bosses arranged in a rectangular shape on the back of the reflector. It is attached to a balcony or a special pole for parabolic antennas via the mounting device. In the future, as the performance of converters further improves, the output of satellites increases, and spot beams become available, reflectors will become smaller and the entire parabolic antenna will become more compact, making it easier to install on balconies, as well as for indoor equipment, vehicle-mounted devices, etc.
Applications are expected to expand to portable types, etc. Furthermore, if the reflector is made smaller, the wind pressure load will be reduced, making it possible to attach it to an existing terrestrial TV antenna support on the roof. Additionally, as the reception area of small antennas expands, it is thought that the use of penetrating rooftop supports will increase in southern regions where the angle of elevation is large. In conventional satellite broadcast receiving parabolic antennas, an offset type reflector is often used, and as shown in FIG. 6, four fixing bosses 100 are arranged on the back side of the reflector. In addition, the center position between the upper and lower fixing bosses can be adjusted with a reflector.
It is customary to place it below the center in the vertical direction. If you try to install a parabolic antenna using a reflector 101 having such four fixing bosses 100 through a support 102 for a terrestrial television antenna, especially in the southern region where the angle of elevation is large, the antenna shown in FIG. The mounting device 103 becomes large as shown in FIG. 8, and an extra part 104 is required as shown in FIG. 8, making it difficult.

[Problem to be solved]

In conventional reflectors with fixing bosses provided at four locations on the back, boss 4 was removed due to accuracy issues during reflector manufacturing.
One plane may not be precisely formed from the top surface of a point, and when the top surface of the boss is used as a reference, there is a lack of precision in measuring the surface accuracy of the reflector paraboloid, which causes problems in quality control of the reflector.

The coplanarity of the top surfaces of these four bosses is determined by the design of the mounting device.
This also has great significance in manufacturing, and due to the relative relationship between the shape of the reflector boss and the mounting device, when the mounting device is fixed with the boss, the reflector paraboloid may be distorted and the focus position may be deviated. In addition, for small reflectors of size 40 or smaller, a four-point boss is too strong in terms of wind pressure load, and there is a limit to how easily the mounting device can be assembled.

Further, when the boss is shifted downward and fixed to a frame mounting device disposed to be attached as a parabolic antenna to a terrestrial TV antenna support on a roof, it is difficult to make the mounting device compact. That is, as shown in FIG.
Particularly in southern regions where the angle of elevation is large, it is necessary to move the reflector away from the terrestrial television antenna support on the roof so that the upper end of the reflector does not hit the support, making it difficult to make the mounting device more compact.

Therefore, this invention provides fixing parts for the mounting device at three locations on the back of the reflector, thereby forming a strict l-plane consisting of the three fixing parts, and creating a reflector paraboloid when fixed to the mounting device. A parabolic antenna that prevents surface distortion, makes the mounting device more compact, and optimizes the positions of the three fixing points, making it possible to make the mounting device more compact even when installing it on an existing terrestrial TV antenna pole on the roof. The purpose is to provide a reflector for

[Failure to solve the problem]

In order to achieve the above object, the present invention provides a reflector.
Three fixing parts of the mounting device on the back are arranged in a triangular shape. Moreover, the center position between the upper and lower fixing parts of the fixing parts of the mounting device disposed at three points on the back surface of the reflector is arranged between approximately the vertical center of the reflector and the upper side.

[Effect]

In this invention, the fixing part of the mounting device has three triangular shapes.
By arranging the points, it is possible to strictly obtain one reference plane formed by the fixed parts at three points, and it is possible to measure the accuracy of a paraboloid based on the fixed parts, etc., by assuming the reflector is mounted as an antenna. quality control becomes easier, distortion of the reflector-paraboloid that occurs when it is fixed to a mounting device can be prevented, and predetermined reception performance can be ensured. In particular, for small reflectors with small wind pressure loads, sufficient mounting strength can be ensured with three fixing points, and the mounting device can be made more compact. In addition, by locating the center position between the upper and lower fixing parts of the fixing parts of the mounting device arranged at three points on the back of the reflector between the vertical center of the reflector and the upper side, it is possible to Even when it is attached to an existing terrestrial TV antenna support, it is possible to avoid increasing the size of the attachment device, and the overall size can be made more compact.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In this example, a boss with a built-in nut was used as the fixing part of the mounting device on the back, but the fixing part is not limited to this. (A simple boss, a boss with a bolt built in, a bolt hole, etc. can also be considered.) .

FIG. 1 shows the arrangement of fixing bosses (fixing parts) 2 on the back surface of an offset type reflector 1. In this embodiment, the fixing bosses (fixing parts) 2 are arranged at three points in a triangular shape, and the center position χ between the upper and lower fixing bosses is 50 to 60% from the bottom and 40% from the top of the long axis of the reflector 1. ~50% position, the vertical width between the bosses is 20 to 35% of the major axis, and the left and right width d between the bosses is 20% of the minor axis l of reflector-1.
~35%. Furthermore, three points are provided, one on the upper side and two on the lower side. By arranging the fixing boss (fixing portion) 2 in this manner, the wind pressure load per fixing boss can be equalized, in other words, an appropriate boss load can be achieved. Furthermore, if one point on the upper side is temporarily fixed with a bolt to the mounting device, the two points on the lower side will also naturally align with the hole positions of the boss and the mounting device, making installation easier.

Moreover, it becomes easier to obtain a reference plane formed by the upper surfaces of the three fixing bosses (fixing portions) 2, and the mounting device can be made more compact.

Next, Table 1 shows the relationship between the size of reflector 1, wind pressure load, and boss load.

Table 1 This reflects the reflector 1 as shown in the graph shown in Figure 3.
If the size is 40 or less, even if there are three fixing bosses (fixing parts) 2, the boss load can be almost the same as in the case of a 45-size boss with four points.

Table 2 below shows examples of the arrangement of fixing bosses for different reflector sizes according to the present invention.

Table 2 FIG. 4 shows a reflector 1 made of aluminum or iron, with a member 4 having three fixing parts 2 fixed to the back surface thereof by rivets or welding. Figure 5 shows members forming part of the mounting device 3 and the fixing part 2 on the reflector 1 made of aluminum or iron.
Indicates a product in which the product and the product are fixed together by rivets or welding.

〔effect〕

As explained above, according to the present invention, the reflector
By arranging the three fixing parts of the phrase device on the back in a triangular shape, a reference plane formed by the three fixing parts can be precisely obtained. Therefore, quality control of the reflector assuming its mounting state as an antenna, such as measuring the accuracy of the paraboloid based on the fixed part, becomes easier, and the distortion of the reflector-paraboloid that occurs when fixed to the mounting device is facilitated. prevent,
Predetermined reception performance can be ensured. The fact that a reference plane can be precisely obtained using the three fixing points is due to the design, manufacturing, and design of the mounting device.
This is also a great advantage in terms of quality control. Furthermore, it is clear that the mounting device can be made more compact with three fixing points than with four fixing parts, provided the fixed pitch is the same. moreover,
If the center position between the fixing parts of the upper and lower mounting devices is placed between approximately the vertical center of the reflector and the upper side, the mounting device will be more compact when it is installed on an existing terrestrial television antenna pole on the roof. It becomes possible to

[Brief explanation of the drawing]

Fig. 1 is a rear view of an offset type reflector showing a preferred embodiment of the present invention, Fig. 2 is a view showing a parabolic antenna using the reflector of the invention attached to a support for a terrestrial television antenna; Figure 3 is a graph showing the relationship between reflector size, wind pressure load, and boss load.
FIG. 6 is a rear view of a conventional reflector, and FIGS. 7 and 8 are diagrams showing a parabolic antenna using a conventional reflector attached to a terrestrial TV antenna support. 1...Reflector 2...Fixing boss (fixing part), 3...Mounting device.

Claims (1)

[Claims] 1. A reflector for a parabolic antenna that fixes a reflector mounting device using a fixing portion provided on the back surface, characterized in that the fixing portions of the mounting device are arranged at three points in a triangular shape. A reflector for a parabolic antenna. 2. A claim characterized in that the center position between the upper and lower fixing parts of the fixing parts of the mounting device disposed at three points on the back surface of the reflector is arranged between approximately the vertical center of the reflector and the upper side. 1. The reflector for the parabolic antenna described in 1.