JPH09270612A - Antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a loss of an input signal due to snow in advance by arranging a snow melt member made of a thermally good conductor on an upper face of antenna along its upper face, connecting a root of the snow melt member to a support and part of the snow melt member to a tip of a support member arranged near an electric heater in a thermal conduction enable way so as to melt snow depositted around a radio wave reception section. SOLUTION: An electric heater 30 is provided to a support 7 that supports an antenna 9, while a snow melt member 34 is arranged along an upper face 90 of the antenna 9. The snow melt member 34 is made of a thermally good conductor, its root is connected in a thermal conduction enable way to the support 7 and part of it is connected to a tip of a support member arranged near the electric heater 30 to be heated. A gap G1 between an upper face 9a of the antenna 9 and the snow melt member 34 is selected smaller at a range not causing affect on the mount of the snow melt member 34. The size of the snow melt member 34 is preferably selected to sufficiently cover the upper face 9a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna that receives an incoming radio wave in a radio wave receiving section for reception.

[0002]

2. Description of the Related Art In an antenna of this type, when snow is deposited on the antenna due to snowfall and is further accumulated, and the accumulated snow comes to cover the radio wave receiving portion of the antenna, the radio waves received by the radio wave receiving portion will be affected. There is a problem that a phase shift occurs, an input loss occurs, and reception failure occurs.

Therefore, in order to remove the reception obstacle due to the adhesion of snow, a snow melting tool equipped with an electric heater is fitted around the antenna, and the electric heater is energized to heat the snow melting tool to the antenna. There is a device in which snow falling toward the antenna is thawed to prevent snow from landing on the antenna (see, for example, Japanese Utility Model Publication No. 2-24242).

[0004]

SUMMARY OF THE INVENTION In the above prior art,
Since the snow melting tool is supported by the antenna, the fitting of the snow melting tool to the antenna may be loose due to the shape of the antenna or a slight tolerance of its size.If it is loose, the snow melting from the antenna will occur due to vibration during use. There was a problem that an accident that a tool falls out easily occurs. or,
Since the snow melting tool is equipped with an electric heater, during use, the connection terminals of the electric heater provided in the snow melting tool are easily corroded, and the lead wires connected thereto are easily damaged by rain wind or sunlight, There was a problem that there were many opportunities for failure. Further, in the above-mentioned conventional one, since the electric heating heater is built in the snow melting tool provided in the place around the antenna where there are many restrictions on the shape or size,
There are many restrictions on the mounting structure or waterproofing, and there is a problem that it is very difficult to design, manufacture, and assemble a snow melting tool in consideration of these restrictions.

The antenna of the present application is provided to solve the above-mentioned problems of the prior art. The purpose is to melt the snow adhering around the radio wave receiving part of the antenna and prevent the loss of the input signal due to the snow in advance. Another object is to enable the snow melting member to be fixedly arranged near the upper surface of the antenna regardless of the shape, size and structure of the periphery of the antenna. Another object is to allow the snow melting member disposed near the antenna to be directly supported by a solid support for supporting the antenna. Another purpose is to provide the snow melting member arranged on the antenna with a good heat conductor from the electric heater provided on the support without providing an electric heater requiring a lead wire around the antenna. By supplying heat energy for snow melting using a holding member, the problems in the prior art in the presence of the heater with a lead wire around the antenna are solved, and as a long-life product over a long period of time. To make it available. Another purpose is to install the electric heater on a solid support so that the electric heater can be installed in a place where there is extremely freedom of installation, unlike the case where the electric heater is installed in a place where there is a restriction around the antenna as in the conventional product. It is possible to increase the degree of freedom in selecting structures such as design, assembly, and water resistance. Other objects and advantages will be more readily apparent from the drawings and the following description associated therewith.

[0006]

In order to achieve the above object, the antenna according to the present invention is an antenna supported by a support, and the support is provided with an electric heater while being formed of a good thermal conductor. A snow-melting member is arranged along the upper surface of the antenna, and the snow-melting member is made of a good heat conductor and has a base connected to the support and a part of the snow-melting member heated near the electric heater. It is connected to the tip of the holding member that is arranged so as to be able to transfer heat.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The drawings showing the embodiments of the present invention will be described below. In FIG. 1 showing the installation state of the parabolic antenna, 1 is a part of the building, and 2 is a pole support attached to the side wall thereof. Reference numeral 3 denotes a pole, which is illustrated as one of supports for supporting an antenna for snow melting, which will be described later, and has a lower end attached to the support 2. In the present specification, the term "support for supporting the snow melting target antenna" refers to a member for fixedly supporting the snow melting target antenna from a fixed object such as the ground or a building. Next, 4 is a parabolic antenna, which is an antenna for receiving radio waves for reception using a parabolic reflector, for example, radio waves of a frequency higher than the SHF band, and for receiving radio waves of satellite broadcasting or radio waves from communication satellites The offset parabolic antenna which carried out is illustrated. The structure of the antenna 4 is the structure known in the above-mentioned known offset parabolic antenna, 5 is a supporting device, 6 is a reflecting mirror, and 7 is a supporting arm exemplified as another supporting member for supporting the antenna of the snow melting target. Is.
Reference numeral 9 denotes a horn-type primary radiator, which is an example of an antenna for snow melting supported by a support, and a support arm 7
It is fixed by being sandwiched between the receiving member 7a and the pressing member 7b provided on the tip of the. In the present specification, the above-mentioned snow melting target antenna refers to an antenna including a radio wave receiving unit for reception. For example, as shown in FIG. 2, it refers to an antenna that is provided with a horn 10 as a radio wave receiving unit and receives radio waves in the horn 10 through its opening 11. Such an antenna may be an independent horn antenna other than the horn-type primary radiator used in the parabolic antenna. Alternatively, the helical antenna shown in FIG. 8 or the microstrip antenna shown in FIG. 9 may be used. Reference numeral 12 denotes a transmitting portion for transmitting a radio wave inside the horn 10, and a tapered transmitting portion 13
And a straight transmission part 14 at the back. 15 is a dustproof and waterproof cap. Reference numeral 16 is a converter, 17 is an output terminal thereof, and 18 is a feeder line for transmitting a received signal. The parabolic antenna 4 may be a parabolic antenna that receives radio waves of the above frequency transmitted from a transmitting antenna on the ground.

Next, 20 is a snow melting device for preventing the reception trouble of the antenna 9 due to snow. The snow-melting device 20 supplies a snow-melting tool 21 for an arm for preventing snow accumulation on the support arm 7, a snow-melting tool 22 for an antenna for preventing adhesion of snow to the antenna 9, and a power for snow-melting to them. And a power supply device 23 for Incidentally, 24 is a power supply cord for receiving commercial power, and 25 is a cord for sending electric power for snow melting to the snow melting tools 21, 22. The snow melting tool 21 is known, for example, in the above-mentioned publication, and is constructed by providing an electrothermal heater on the inner surface of a frame body 26 formed of a good heat conductor such as aluminum in a shape as shown in FIG. Incidentally, FIG. 6, FIG. 7 and FIG.
Reference numerals 26a, 26b, and 26c for attaching the frame body 26 to the support arm 7 are as follows: 26a is a through hole, 26b is a screw hole, and 26c is an attaching screw. The power supply device 23 is a snow melting tool 21, 22.
It is provided to supply power at a safe voltage to
For example, it receives a commercial power of 100 V and converts it into a safe low voltage of 30 V, for example, and supplies it.

Next, the snow melting tool 22 will be described with reference to FIGS. The snow melting tool 22 comprises a heat source portion 27 and a heat radiating portion 28 which receives heat from the heat source portion 27 and radiates the heat to melt the snow. First, the heat source
Explain 27. Reference numeral 29 denotes an attachment frame for attaching the electric heater to the support arm 7, which is fixed to the support arm 7. For example, the lower end portion 29a is integrally formed with the frame body 26, and the frame body 26 is fixed to the support arm 7 so that the attachment frame 29 is fixed to the support arm 7. 29b
Is an attachment piece arranged along the side surface of the support arm 7 in order to increase the stability of the mounting frame 29. 30 is the above antenna 9
The electric heater is designed to generate heat to prevent snow from adhering to the reception obstacle, and is exemplified as the support in order to achieve a stable arrangement state regardless of its shape and structure. The supporting arm 7 is equipped with the same. As the electric heater 30, a heater having excellent electrical insulation property in which the outer circumference of the resistance heating wire is completely covered with an insulating coating is used. What is called a ceramic heater may be used as the electric heater 30. The heat transfer heater 30 is connected to the cord 25. As an example of means for providing the electrothermal heater 30 on a support, the heat transfer heater 30 is arranged along the inner surface of the mounting frame 29 and is fixed thereto by a heat transfer member 31 described below. The heat transfer member 31 is for efficiently transmitting the heat of the electric heater 30 to the mounting frame 29, and is a foil (thickness of about 0.3 mm) of a metal material having a high thermal conductivity such as aluminum (or copper).
And is adhered to the inner surface of the mounting frame 29. 32
Is a heat insulating member for preventing the heat of the electric heater 30 from radiating to an unnecessary side (the side of the support arm 7) by radiation, and is, for example, urethane resin.

Next, the heat radiating portion 28 is formed in a ring shape surrounding the antenna 9 as shown in FIG. 3, and can be loosened and tightened so that it can be adjusted according to the shape, position or mounting angle of the antenna 9. Mounting frame 29 using fasteners such as screws 33
It is attached to. The mounting frame 29 may be integrally formed or welded. The heat radiating portion 28 is made of a material having high thermal conductivity, such as aluminum (iron, brass, etc.), in order to enhance heat transfer and snow melting efficiency.
It is formed by.

The snow melting tool 22 will be further described. Reference numeral 34 is a snow melting member for preventing snow from adhering to or accumulating on the upper surface 9a of the antenna 9, and is arranged along the upper surface 9a of the antenna 9. The upper surface 9a of the antenna is the radio wave receiving portion of the antenna 9, for example, the opening portion of the horn 10, when the snow falling on the outer surface of the antenna 9 adheres to or is further accumulated there.
11 refers to a surface that may be in a state of partially or entirely covering up, such as the opening 11 in the horn 10.
It is a surface facing upward or sideward of the nearby outer peripheral surface. The snow melting member 34 is arranged along the upper surface 9a so that the snow melting member 34 can be fixedly arranged near the upper surface 9a of the antenna 9 regardless of the shape, size, and structure of the outer circumference of the antenna 9. And in the arrangement state, the upper surface
This is to prevent snow from adhering to or accumulating on 9a. For example, the gap G1 between the upper surface 9a of the antenna 9 and the snow melting member 34 is set small in the present embodiment within a range that does not hinder the attachment of the snow melting member 34 in the state as shown in FIG. It is preferable that the size of the snow melting member 34 is large enough to cover the upper surface 9a in order to complete the prevention of snow adhesion to the upper surface 9a. The snow melting member 34 in this example is a part of the heat radiating portion 28 and serves as the snow melting member up to the point indicated by the reference numeral 34a in FIGS. 3 and 4 (the upper surface 9a where the snow is likely to adhere to the antenna 9). The portion facing) functions as the snow melting member 34. The snow melting member 34,
It is made of a good thermal conductor so that snow can be melted by the heat transmitted from other things. This snow melting member
The good thermal conductor forming 34 refers to a material that can transmit heat to the extent that the snow falling on the snow melting member 34 can be melted one after another by the heat transmitted through the snow melting member 34 by conduction. Any general metal material can be used, but aluminum is exemplified here. It may be iron or brass. The thickness is, for example, about 1 mm.

Next, numeral 35 indicates a holding member for holding the snow melting member 34. The holding member 35 enables adjustment of the positional relationship of the snow melting member 34 with respect to the antenna 9,
In this example, the base element 36 and the variable element 37 are included. The base element 36 uses, for example, the mounting frame 29, and the variable element 37 uses the lower portion of the heat radiating portion 28 (the portion below the portion indicated by reference numeral 34a). Base element 36
The joint surface 35a of the variable element 37 and the variable element 37 are polymerized so that heat transfer can be performed with low resistance. The holding member 35 is formed of a good heat conductor in order to transfer the heat of the electric heater 30 to the snow melting member 34 by heat conduction. The good thermal conductor forming the holding member 35 refers to a material having thermal conductivity capable of sufficiently transmitting the heat required for melting snow in the snow melting member 34 from the electric heater 30 to the snow melting member 34. . For example, the base element 36 is made of aluminum having a thickness of about 2 mm, and the variable element 37 is made of aluminum having a thickness of about 1 mm. The holding member
In order to hold the snow-melting member 34 stably, the base 35 is connected to the support. For example, it is fixed to the support arm 7 by using the mounting frame 29 as the base element 36. A part of the holding member 35 is arranged in the vicinity of the electric heater 30 so as to be heated so as to receive the heat generated by the electric heater 30. For example, by mounting the electric heater 30 on the mounting frame 29 as described above, the mounting frame 29 as the base element 36 is heated by the electric heater 30. The snow melting member 34 is connected to the tip of the holding member 35 as described above so as to be able to transfer heat. For example, by integrally forming the snow melting member 34 and the variable element 37, heat transfer from the variable element 37 to the snow melting member 34 can be performed with a small thermal resistance.

In the above structure, the snow melting tool 22 is attached to the antenna 9 by covering the antenna 9 from the state shown in FIG. 7 as indicated by the arrow 38, and as shown by reference numeral 39, the through hole 26a and the screw hole 26.
The frame 26 is fixed to the support arm 7 by means of the screw 26c in a state where the frame b is polymerized. By this fixing, the snow melting tool 21 is attached to the support arm 7. The heat transfer heater 30 in the snow melting tool 22 is provided on the support arm 7, and the holding member 35 is connected to the support arm 7. The support arm 7
The fixing of the frame body 26 to the rivets may be performed by rivets, or a pair of recesses and protrusions that fit with each other may be provided and the recesses and protrusions may be fitted together. .

When the parabolic antenna to which the snow melting tools 21 and 22 are attached is used, the radio waves coming from the transmitting equipment, for example, the broadcasting satellite as shown by the arrow 40 are reflected by the reflecting mirror 6 and shown by the arrow 41. Antenna 9 while converging
Head for. The radio wave is received by the antenna 9, the received signal is frequency-converted into an intermediate frequency by the converter 16, and is transmitted to the television receiver in the room, for example, via the power supply line 18.

In the above-mentioned use state, when the outside air temperature falls below a predetermined temperature, power is supplied from the power supply device 23 to the snow melting tools 21, 22 and their electric heaters generate heat. Therefore, even if there is snowfall, the snow is thawed by the snow melting tools 21 and 22, and is prevented from being accumulated on the arm 7 or the antenna 9. Therefore, the reception can be stably performed even during snowfall.

The operation of the snow melting tool 22 is as follows. The electric heater 30 generates heat when energized. The heat is transferred to the base element 36 both directly and through the heat transfer member 31. Further, the heat is transmitted through the base element 36 as shown by the arrow 43 in FIGS. The heat then heats the base element 36 as indicated by arrow 44.
Is transmitted from the variable element 37 to the variable element 37 through the joint surface 35a of the both, and is transmitted to the variable element 37 as indicated by an arrow 45. Then, as indicated by an arrow 46, the variable element 37 is transmitted to the snow melting member 34. The snow melting member 34 is heated by such heat conduction. As a result, even if snow falls on the antenna 9, the snow touches the snow melting member 34 before reaching the upper surface 9a of the antenna 9 and is melted there. As a result, the antenna 9
The upper surface 9a of the antenna 9 is prevented from being covered with snow, and the radio wave receiving portion of the antenna 9 is prevented from being covered with snow to cause a reception failure.

Next, FIGS. 8 and 9 show different examples of the snow melting target antenna. FIG. 8 shows a helical antenna.
Denote microstrip antennas, respectively. The helical antenna shown in FIG. 8 is supported by a support arm 7. That is, 61 is the base of the antenna, which is fixed to the support arm 7 by being sandwiched between the receiving member 7a and the pressing member 7b. 62 is an antenna element exemplified as a radio wave receiving part, which is known as a helical antenna element, and is an insulator.
It is attached to the base 61 via 63. Reference numeral 64 is a cap for preventing dust and rainwater from adhering to the antenna element 62 and mechanically protecting the antenna element 62. The microstrip antenna shown in FIG. 9 is supported by a support arm 7 as in the helical antenna as shown in the figure.
Reference numeral 71 indicates the base of the antenna. Reference numeral 72 denotes a receiving element exemplified as a radio wave receiving unit, which is known as a microstrip element or patch, and is an insulator for supporting the element.
It is attached to the base 71 via 73. 74 indicates a cap for the same purpose as above. Note that, in FIGS. 8 and 9, parts that are functionally the same as or equivalent to those in the previous figure and are considered to be redundant in description will be given the same reference numerals as those in the previous figure, and redundant description will be omitted.

[0018]

As described above, according to the present invention, it is possible to prevent snow accumulating on the antenna 9 by melting the snow falling toward the antenna 9 and prevent the input loss of the radio wave signal in advance. Moreover, since the snow melting member 34 for snow melting is directly attached to the solid support 7 through the holding member 35,
Irrespective of the outer peripheral structure and shape of the antenna 9, there is an effect that it can be placed above the antenna 9 and utilized for snow melting for a long period of time. Further, the snow melting member 34 receives heat for snow melting from the heater 30 provided in the support 7 through the holding member 35 of a good thermal conductor,
It is not necessary to provide a heater on its own, so there is no need to provide a terminal that is susceptible to corrosion as in conventional products in a snow melting member, or to connect a lead wire with poor weather resistance to that terminal. It has the feature of not worrying about breakdowns and has the effect of being usable over a long period of time (long life). Further, since the heater 30 is provided on the support 7 that is firmly formed to support the antenna 9, the heater 30 is installed when the structure is waterproof or rainproof, or when the type of the heater 30 is selected. There is a high degree of freedom in the selection of the structure, designing, manufacturing, and assembling are extremely easy, and there is also a manufacturing effect that the cost of a robust and long-life product can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing an installed state of a parabolic antenna.

FIG. 2 is a partially cutaway side view showing an antenna for snow melting and a snow melting tool for the antenna.

FIG. 3 is a front view showing an antenna for snow melting and a snow melting tool for the antenna.

FIG. 4 is a sectional view taken along line IV-IV in FIG. 2;

FIG. 5 is a sectional view taken along line VV in FIG. 2;

FIG. 6 is a perspective view of a snow melting tool.

FIG. 7 is a side view for explaining attachment of the snow melting tool to the antenna.

FIG. 8 is a partially cutaway side view showing a different example of an antenna for snow melting.

FIG. 9 is a partially cutaway side view showing still another example of an antenna for snow melting.

[Explanation of symbols]

 7 Support 9 Antenna for snow melting 30 Electric heater 34 Snow melting member 35 Holding member

Claims (1)

[Claims] 1. An antenna supported by a support, wherein the support is provided with an electrothermal heater, and a snow melting member formed of a good thermal conductor is arranged along the upper surface of the antenna, and the snow melting member is provided. Is made of a good heat conductor and has a base portion connected to the support and a part of which is capable of transferring heat to a front portion of a holding member which is arranged near the electric heater and is capable of being heated. An antenna characterized by being connected.