JP3022767B2 - Lightning resistant waveguide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the prevention of lightning strikes in radio communication devices, and more particularly to a connection waveguide for connecting an antenna and a radio communication device.

[0002]

2. Description of the Related Art A conventional lightning strike prevention measure for a wireless communication device is to provide a ground wire from a part of a connecting waveguide section connecting an antenna and the wireless communication device to the ground and to release a lightning surge to the ground. Had been.

[0003]

In the above conventional countermeasures against lightning strikes, all of the lightning surges are not grounded, and some of the lightning surges enter the device from the waveguide to the wireless communication device and give a fault to the device. There was a problem.

[0004] It is an object of the present invention to provide a lightning-resistant waveguide capable of preventing the destruction of device parts due to a lightning surge transmitted from a connection waveguide portion connecting a transmitting / receiving antenna and a wireless communication device and entering the wireless communication device during a lightning strike. Is to provide a tube.

[0005]

According to the present invention, between a first waveguide and a second waveguide each having a flange portion, insulation is provided against lightning surge, A sheet plate having transparency with respect to a desired radio wave is sandwiched, and the first
In order to couple the second waveguide, a substantially U-shaped fixed cover made of an insulator and an approximately U -shaped concave portion of the fixed cover are provided at upper and lower portions of the two flange portions. comprising a fitted, fixed bars made of metal, respectively a pair of the fixed cover member, fixedly joined to said first and said second waveguide, fixing the pair through the pair of the fixed cover From one side of the bar to the other, the flanges
The lightning-resistant waveguide is obtained by tightening bolts / nuts in a region outside the cross-sectional region of the portion .

Further, according to the present invention, in order to position the two flange portions, there are provided concave portions having shapes corresponding to upper and lower outer peripheral shapes of the both flange portions, respectively.
A first positioning plate and a second positioning plate made of an insulator are provided, and concave portions of the first and second positioning plates are respectively brought into contact with upper and lower outer peripheral surfaces of the flange portions. Thus, a lightning-resistant waveguide is obtained in which the joint surface between the first and second waveguides is positioned.

Further, according to the present invention, the first position
Left and right ends at the decision plate and the second positioning plate respectively
A recess for fixing is formed near the first positioning plate.
Of the second positioning plate is fixed to the second positioning plate, respectively.
1 from the recesses near the left and right ends of the positioning plate.
2 over the dents near the left and right ends of the positioning plate.
It is performed by tightening the nut / nut
A lightning waveguide is obtained.

Further, according to the present invention, the two flanges are provided.
Of the two waveguides of at least one of the flanges
Choke grooves along the outer circumference on the side surface on the joint surface side
For lightning proof characterized by having at least one formed
A waveguide is obtained.

Further, according to the present invention, the first and the front are provided.
The front surface of the sheet plate is provided between the two opening surfaces between the second waveguides.
While in contact with the surface, the reflected wave generated in both waveguides is
Eye with window to eliminate and adjust radio wave transmission characteristics
A lightning proof waveguide characterized by being provided with a squirrel is obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIG. FIG. 1A is a front view of a lightning-resistant waveguide according to the present invention, which is partially broken. FIG. 1B is a side view of FIG. 1A, and FIG. 1C is a plan view of FIG. 1A.

The built-in structure of the lightning-resistant waveguide according to the present embodiment is such that a lightning surge is applied between the first waveguide 1 and the second waveguide 2 to each of which the flange portion 12 is attached and fixed. A sheet plate 3 having an insulating property and a transmitting property for a desired electric wave is sandwiched. This sheet plate 3
Thus, the lightning surge transmitted to the waveguide can be completely cut off.

The first waveguide 1, the second waveguide 2, and the sheet plate 3 are joined and fixed by the first waveguide 1 and the second waveguide 2.
A substantially U-shaped fixed cover 5 made of a pair of insulators and a fixed bar 6 made of metal fitted into a fitting portion of the fixed cover 5 are provided at upper and lower portions of both flange portions 12 of the waveguide 2 respectively. A fixed cover body is provided. The first waveguide 1 and the second waveguide 2 are joined and fixed by the two flange portions 12.
A pair of fixed covers 5 are brought into contact with the upper and lower portions of the pair of fixed bars 5 so as to sandwich both flange portions 12, and a bolt 7 a and a nut 7 b are applied from one side to the other of the pair of fixed bars 6 fitted into the fitting portion of the fixed cover 5. It is carried out by tightening the bolt 7a.

A first positioning plate having a two-part structure for positioning the outer peripheral surfaces of both flange portions 12, that is, for positioning the joint surface between the first waveguide 1 and the second waveguide 2. 8a and a second positioning plate 8b are provided. Specifically, each of the first positioning plate 8a and the second positioning plate 8b has a concave portion having a shape corresponding to the outer peripheral shape on the upper and lower sides of both flange portions 12, respectively. First and second
The concave portions of the positioning plates 8a and 8b are respectively brought into contact with the upper and lower outer peripheral surfaces of both flange portions 12 to position the joint surface between the first waveguide 1 and the second waveguide 2. I have.

The first positioning plate 8a and the second positioning plate 8b are formed with fixing recesses 11 near the left and right ends, respectively, and the second positioning plate 8a of the first positioning plate 8a is formed.
The fixing of the first positioning plate 8a to the right and left ends of the second positioning plate 8b is performed so as to cover the outer peripheral portions of both flange portions. 11 is performed by tightening the bolt 7a using the bolt 7a and the nut 7b. In the present embodiment, the first waveguide 1 and the second waveguide 2 are joined and fixed, and the first positioning plate 8a is fixed to the second positioning plate 8b by bolts. Although a nut is used, a bolt may be passed from one side and a male screw (male groove) formed at the tip of the bolt may be screwed into a female screw (female groove) cut into the other.

As a result, it is possible to prevent the occurrence of a junction step between the inner walls of the junction between the first waveguide 1 and the second waveguide 2 and to smoothly transmit the radio wave in the waveguide. Become. Here, as a material used for the fixed cover 5 and the positioning plate 8, a material having an insulating property against a lightning surge, for example, a resin or the like is used to prevent the lightning surge from entering the waveguide main body. The material used for the fixing bar 6 is a metal such as aluminum in consideration of the mounting strength.
The material used for the sheet plate 3 is, for example, Teflon or the like having insulation and radio wave transmission.

On the other hand, the sheet plate 3 transmits the radio wave in the waveguide, but blocks the inside of the waveguide.
Is provided, the propagation path of the radio wave is disturbed, and a reflected wave and a leaky wave that adversely affect communication are generated. In order to eliminate the reflected wave and adjust the transmission characteristics of the radio wave, the contact between the first waveguide 1 and the second waveguide 2 was made between the opening surfaces and the surface of the sheet plate 3. In this state, an iris 10 having an adjustment window is provided. Further, in order to eliminate (absorb) the leakage wave, the choke groove 4 is formed on the side surface of at least one of the flange portions 12 on the joint surface side of the two waveguides 1 and 2 along the outer periphery thereof.
Are formed. The shape of the choke groove 4 is determined so as not to leak when a desired frequency band passes. In the present embodiment, the flange portion 1 on the first waveguide 1 side is used.
2. In this case, the number of the choke grooves 4 may be one or more. Further, it may be provided on the flange portion 12 on the second waveguide 2 side, or may be provided on both flange portions 12.

From this embodiment, it can be easily guessed that a fixing method for fixing the joint portion of the two waveguides with an insulating resin is used.

[0018]

As described above, according to the present invention, a waveguide structure having insulation properties against lightning surge is provided.
The incorporation of the lightning proof waveguide of the present invention into a part of the connection waveguide that connects the transmission / reception antenna to the wireless communication device can completely prevent the lightning surge from entering the wireless communication device. A communication system that enables stable communication can be constructed.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first waveguide 2 second waveguide 3 sheet plate 4 choke groove 5 fixing cover 6 fixing bar 7a bolt 7b nut 8a first positioning plate 8b second positioning plate 10 iris 11 recess 12 flange portion

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Manabu Kinoshita 5-7-1 Shiba, Minato-ku, Tokyo Within NEC Corporation (72) Inventor Takashi Koshio 3- 50-1 Kamiishihara, Chofu-shi, Tokyo Inside Anten Co., Ltd. (72) Inventor Hajime Takakura 3-50-50 Kamiishihara, Chofu City, Tokyo Inside Anten Co., Ltd. (72) Inventor Yoshiaki Kobayashi 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electric Power Company (72) Inventor Tadao Watanabe 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Tokyo Electric Power Company (56) References JP-A-55-75302 (JP, A) JP-A-57-69901 (JP, A) JP-A-52-130266 (JP, A) JP-A-53-56741 (JP, U) JP-A-2-53601 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01P 1/04

Claims (5)

(57) [Claims] 1. Between a first waveguide and a second waveguide each having a flange portion, it has an insulating property against a lightning surge, and has a transmitting property against a desired radio wave. A substantially U-shaped fixed cover made of an insulator on the upper and lower portions of the two flange portions so as to sandwich the sheet plate and to couple the first and second waveguides; The abbreviation of
A pair of fixed cover bodies each comprising a metal fixed bar fitted in a U-shaped concave portion are provided , and the first and second waveguides are joined and fixed by the pair of fixed covers. From one side of the pair of fixing bars to the other, in a region outside the cross-sectional region of the two flange portions,
A lightning proof waveguide characterized by being tightened with bolts / nuts. 2. In order to position the flange portions, have a respective recess having a shape corresponding to the outer peripheral shape of the upper and lower side of the flange portions, the first positioning plate made of an insulating material and the 2 positioning plates, and the concave portions of the first and second positioning plates are respectively brought into contact with the upper and lower outer peripheral surfaces of the two flange portions, respectively. 2. The lightning proof waveguide according to claim 1, wherein the joint surface is positioned. 3. The first positioning plate and the second positioning plate are each provided with a fixing recess near both left and right end portions, and the first positioning plate is attached to the second positioning plate. 3. The fixing device according to claim 2, wherein the fixing is performed by tightening bolts / nuts from the recesses near the left and right ends of the first positioning plate to the recesses near the left and right ends of the second positioning plate. A lightning-resistant waveguide as described. 4. A choke groove is formed on a side surface of at least one of the two flange portions on the joint surface side of the two waveguides along an outer periphery thereof. The lightning-resistant waveguide according to claim 1. 5. A reflected wave generated in the two waveguides between the first and second waveguides in a state of being in contact with the surface of the sheet plate in a state of being in contact with the surface of the sheet plate. 5. The lightning proof waveguide according to claim 1, further comprising an iris having a window for adjusting transmission characteristics.