JP2004247915A

JP2004247915A - Antenna and its manufacturing method

Info

Publication number: JP2004247915A
Application number: JP2003034972A
Authority: JP
Inventors: Masashige Hiramatsu; 正成平松
Original assignee: Maspro Denkoh Corp
Current assignee: Maspro Denkoh Corp
Priority date: 2003-02-13
Filing date: 2003-02-13
Publication date: 2004-09-02
Anticipated expiration: 2023-02-13
Also published as: JP4064836B2

Abstract

<P>PROBLEM TO BE SOLVED: To press the tip side of a rib 3 against an antenna element for fixing the antenna element to a boom by providing the rib 3 inside a pipe of the boom, fixing the base portion side of the rib 3 to a pipe wall 4, setting the tip side 3b of the rib 3 to be a free end, and simply deforming the pipe wall of the boom. <P>SOLUTION: The hollow tubular antenna element is allowed to pass through the hollow boom. Recesses are formed at both sides on a circumferential face at a portion positioned in the boom pipe of the antenna element. In the pipe of the boom, ribs are provided at both sides of the antenna element. The base side of the each rib is fixed to the pipe wall of the boom. Free end sides of the rib face the recesses formed at both sides of the pipe wall of the antenna element. The pipe wall of the boom is deformed for allowing the free end side of the rib to come into contact with the recess. The antenna element is fixed to the boom while the antenna element is clamped from both the sides. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、例えばＵＨＦ、その他の通信信号の送受をする場合に、ブームの軸心方向に適当な間隔を隔てて複数個の貫通孔を備えさせ、その貫通孔に対して、パイプ状のアンテナ素子を貫通させた状態で固定して利用する形式のアンテナに関するものである。
【０００２】
【従来の技術】
従来より、ブームの軸心方向の適当な間隔を隔てた位置に、夫々ブームの軸心に対して直交する方向に向けた複数個の貫通孔を備えさせ、上記複数個の貫通孔の夫々にパイプ状のアンテナ素子を貫通させ、これらのアンテナ素子をブームに夫々固定させたアンテナ及びそのようなアンテナを製造する方法は広く知られている（例えば、特許文献１参照）。
上記従来の固定手段は、アンテナ素子の管内に可塑性材料で形成されている金属製の中空管を挿入し、それをブームの軸心を中心として位置させ、その中空管内に両側から棒状治具の先端を挿入し、両側から加圧することにより中空管の入口を半径方向に変形させて、その変形作用によりアンテナ素子におけるブーム内の管壁の全周を夫々径方向に拡張させてブームの貫通孔の内側の孔縁に圧接させることによりアンテナ素子をブームに固定させる手段を用いている。
【０００３】
【特許文献１】
特開昭５７−１１５００１号公報（図３，図６）
【特許文献２】
実開昭５７−２７０７号公報（図３）
【０００４】
【発明が解決しようとする課題】
この従来のアンテナの製造方法では、中空管における両端の管口の拡張の度合が、中空管における中央部における拡張の度合よりも大きくなり、必然、アンテナ素子におけるブーム内の管壁における孔縁近くの管壁が急激な角度でもって径方向に局部的に拡張される。このように管壁の一部が局部的に拡張されると経時使用によって、そこが繰返し曲げ荷重を集中的に受けて傷む等、耐久性に欠ける問題点があった。また一つのアンテナ素子に対して一つの中空管を消耗品として必要とする為部品コストが嵩み生産コストを高める問題点もあった。
そこで上記消耗品を節約する為に、アンテナ素子におけるブーム内の管壁における孔縁近くの管壁を消耗品を用いることなく機械的に膨出させる手段として図５に示されるものがある（例えば、特許文献２参照）。
【０００５】
このような公知の手段により製造されるアンテナは、製造時において、ブーム２の管内にアンテナ素子６を貫通させ、アンテナ素子６をブーム２に固着させる作業は、棒状治具１４，１４の夫々の先端における傾斜状態の対向面１５，１５を図５（Ａ）の準備状態に成し、次に、棒状治具１４，１４の夫々の先端における傾斜状態の対向面１５，１５を、図５（Ｂ）の位置にまで両側から前進させる。すると傾斜状態の対向面１５，１５の重なりが大きくなることにより、そこの対向面１５，１５の重なり部分の外周が大きくなり、アンテナ素子６の内径を図示のように膨らます。しかしかかる作業において対向面１５，１５の間にゴミ１６が介在した場合には、対向面１５，１５の重なり部分の外周が予定寸法よりも大きくなり、図示のようにブーム管壁４の孔縁４ｂ近くに形成予定の膨出部７ａの膨出量が、予定したよりも大きく突出し、ブームの管壁の孔縁４ｂ近くにおいてアンテナ素子６の管壁７を破損させる問題点があった。
また、傾斜状態の対向面１５，１５の重なりが予定よりも少ない場合には、アンテナ素子６の膨出部７ａがブーム２の管壁の孔縁４ｂ近くに突出せず、予定した場所よりもブーム２の管内の中間部寄りに膨出部７ａが突出する。すると膨出部７ａがブームの孔縁４ｂの内側に接しないで離れ、アンテナ素子は固着されず、軸芯方向にずれ、不良品発生率を高める問題点があった。
【０００６】
また、予定通りブーム２の管壁の孔縁４ｂ近くに膨出部７ａを突出させ、アンテナ素子６を固着したものであっても、アンテナが暴風雨に晒されて、ブーム２とアンテナ素子６が暴風雨による振動を受けたとき、ブーム２から突出するアンテナ素子はブームの管壁の孔縁４ｂ近くにおける上記膨出部７ａ近くを支点として振動する。
このことは、アンテナ素子が共振現象により、上記弱体化している膨出部７ａ近くを支点として繰返し曲げ荷重を受けることになり、アンテナ素子の管壁は、膨出部７ａ近くで金属疲労によって局部的に傷み、折損する問題点があった。
【０００７】
本件出願のアンテナは、上記従来技術の問題点を解決する為に提供するものである。
本件出願の目的は、中空のブームに対し、アンテナ素子を固定した状態においてその固定部分が外部からは見ることができず、外観的に美しい状態で固着されたアンテナを提供しようとするものである。
本件出願の他の目的は、アンテナが暴風雨に晒されてアンテナ素子が暴風雨により共振的な振動を受けたときでも、ブームから突出するアンテナ素子の元部の止付部分はあまり影響を受けないように、ブーム管内における上記ブームの管壁孔から離れた中間寄りの位置に設定し、アンテナ素子の受け止めは、ブームの管壁における孔縁でアンテナ素子の途中を受け止めるようにして止付部分に対する共振現象を柔らかなものにし、アンテナ素子におけるブームの管壁孔縁近くの損傷を防ぎ、アンテナ素子の寿命を高いものにすることのできるアンテナを提供しようとするものである。
【０００８】
本件出願の他の目的は、ブームにアンテナ素子を貫通させ、アンテナ素子をブームに固着させる作業のとき、従来品のように、固着場所がブームの内壁の孔縁近くに制限されるような恐れはなく、ブーム内におけるアンテナ素子の固着場所の選定幅が広くて、ラフな加工精度でもって両者の結合場所の選定が出来るようにしたものであり、もって加工能率が上がるように構成したアンテナを提供しようとするものである。
本件出願の他の目的は、ブームにアンテナ素子を貫通させ、アンテナ素子をブームに固着させる作業のとき、単純に上記ブームの管壁を変形させて、ブーム管内のリブの自由端を中空管状アンテナ素子の管壁に押し当てる操作でもって、中空管状のアンテナ素子の外周面に凹部を形成し、同時にリブの自由端を嵌合させることのできるようにしたアンテナを提供しようとするものである。
他の目的及び利点は図面及びそれに関連した以下の説明により容易に明らかになるであろう。
【０００９】
【課題を解決するための手段】
本願発明におけるアンテナは、中空のブームの管壁には、軸心方向に適当な間隔を隔てて、夫々中空管状のアンテナ素子をブームの軸心に直交する方向に貫通させる為の二個一対の管壁孔を複数備え、上記二個一対の管壁孔の夫々には中空管状のアンテナ素子を貫通させ、かつ、それらのアンテナ素子は夫々上記ブームに固着してあるアンテナにおいて、上記ブームに対するアンテナ素子の固着は、上記中空管状のアンテナ素子におけるブームの管内に位置する部分であって、上記ブームの管壁における管壁孔から離れた位置にある上記アンテナ素子の周面における両側に、夫々凹部を形成し、一方、ブームの管内においては、断面形状においてアンテナ素子を中間にしてそれの両側位置に夫々上記ブームの軸心方向に伸びるリブを備え、かつ、それらのリブの断面形状における元部側は、夫々ブームの管壁に一体的に固着してあり、リブにおける元部側から自由端側に向けての方向は、上記存置予定位置に置かれるアンテナ素子の軸線に対して交差する方向に設定して、夫々のリブの自由端側を、上記アンテナ素子の管壁における両側に形成された凹部の谷部に対して夫々アンテナ素子の軸線に対して交差する方向から加圧する状態で当接させ、上記アンテナ素子を両側から挟持する状態で、上記ブームにアンテナ素子を固着したものである。
【００１０】
また好ましくは、中空のブームの管壁には、軸心方向に適当な間隔を隔てて、夫々中空管状のアンテナ素子をブームの軸心に直交する方向に貫通させる為の二個一対の管壁孔を複数備え、上記二個一対の管壁孔の夫々には中空管状のアンテナ素子を貫通させ、かつ、それらのアンテナ素子は夫々上記ブームに固着してあるアンテナにおいて、上記ブームに対するアンテナ素子の固着は、上記中空管状のアンテナ素子におけるブームの管内に位置する部分であって、上記ブームの管壁における管壁孔から離れた位置にある上記アンテナ素子の周面における両側に、夫々凹部を相互に離間させた状態で複数カ所宛形成し、一方、
ブームの管内においては、断面形状においてアンテナ素子を中間にしてそれの両側位置に夫々上記ブームの軸心方向に伸びる各複数条のリブを夫々並列状態で備え、かつ、それらのリブの断面形状における元部側は、夫々管壁孔の側の管壁に一体的に固着してあり、夫々のリブにおける元部側から自由端側に向けての方向は、上記存置予定位置に置かれるアンテナ素子の軸線に対して交差する方向に設定して、夫々のリブの自由端側を、上記アンテナ素子の管壁における両側に形成された凹部の谷部に対して夫々アンテナ素子の軸線に対して交差する方向から加圧する状態で当接させ、上記アンテナ素子を両側の複数カ所から挟持する状態で、上記ブームにアンテナ素子を固着したものである。
【００１１】
また好ましくは、中空のブームには、その内側において、断面形状でアンテナ素子の存置予定位置の両側となる位置に、夫々上記ブームの軸心方向に伸びるリブを備えさせ、それらのリブの断面形状における元部側は、夫々ブームの管壁に一体的に固着し、夫々のリブの断面形状における先端側は自由端とし、リブにおける元部側から先端側に向けての方向は、上記存置予定位置に置かれるアンテナ素子の軸線に対して交差する方向に設定してあり、さらに上記ブームには、軸心方向に適当な間隔を隔てて、中空管状のアンテナ素子をブームの軸心に直交する方向に貫通させる為の二個一対の管壁孔が複数備えられており、次に上記二個一対の管壁孔に夫々中空管状のアンテナ素子を貫通させて上記存置予定位置にアンテナ素子を置き、次に、上記ブームの管壁を変形させて、ブーム管内のリブの自由端を上記中空管状アンテナ素子の管壁に押し当てて、中空管状のアンテナ素子の外周面を凹ませ、リブの自由端と中空管状のアンテナ素子の外周面における凹部との嵌合により、中空管状のアンテナ素子の回動と、アンテナ素子の長手方向への移動を阻止するようにしたものであればよい。
【００１２】
【発明の実施の形態】
以下本願発明の実施の形態を示す図面について説明する。図１乃至図３において、１はＶＨＦ〜ＵＨＦ波などの任意の通信信号（画像信号を含む）の送受に利用される周知のアンテナを示す。２は、周知のようにアルミニウム或は塑性変形可能な硬質材等によって形成された断面が丸（又は図４に示すような六角を含む多角形状）の中空のブームを示し、通常建造物の上に樹立させたマスト１ａの上方に装着され、通信の送受の方向に向けて配置される。
ブーム２の軸心方向においては、図１に示されるように導波器１０、放射器８、反射器９を高周波的に適当な間隔を隔てた位置に備えている。
導波器１０が設けられているブーム２にあっては、夫々ブーム２の軸心に対して直交する方向に向けて適当な間隔を隔てて、複数個の貫通孔４ａを備える。
この中空ブーム２の管壁４に設けた貫通孔４ａは、中空管状のアンテナ素子６をブームの軸心に直交する方向に貫通させる為の二個一対の管壁孔４ａとなっている。
【００１３】
図１、図２、図３、図４に示される中空のブーム２の内側には、図示されるように断面形状（図２（Ｂ）に現れるような横断面）においてアンテナ素子６を中間にしてそれの両側位置に夫々ブーム２の軸心方向（図２（Ａ）の縦断面における左右方向）に伸びるリブ３を備える。
それらのリブ３の断面形状における元部側３ｃは、夫々管壁４と一体材でもって一体的に成形して固着状態にしてある。
リブにおける元部側３ｃから自由端側３ｂに向けての方向は、図２（Ｂ）、図４に現れているように、上記存置予定位置に置かれるアンテナ素子６の軸線に対して交差する方向に設定してあり、進行先はアンテナ素子６の外周面７に向けられている。
夫々のリブ３の断面形状における先端側３ｂ、３ｂは、自由端に構成してある。従って、ブーム２の内部には、図２、図３、図４に示されるように、上下のリブ３、３の間にアンテナ素子６の一部分６ａが存在することになる。
【００１４】
次に、図２はブーム管壁変形前の状態を示すものであり、ブーム２の断面形状は、やや楕円形に形成してあり、長径Ｄ１に対して短径Ｄ２が僅かに小さくなっている。この状態においてリブ３の長さＳ１は、アンテナ素子６の外周面に達するに十分な長さに設定してある。
従って、相対向するリブ３、３の先端側３ｂ、３ｂの間の寸法Ｓ２は、アンテナ素子６の直径Ｄ５よりも小さくなっている。またこのような事情から、リブ３、３の先端側３ｂ、３ｂにおけるアンテナ素子６の外周面７と重合する部分においては、図２（Ａ）に示されるようにリブ３の先端側３ｂ、３ｂの一部がアンテナ素子６の外周面７に沿わせる状態で円弧状に除かれている。その削除の手段としては、例えば上記二個一対の管壁孔４ａ、４ａを穿孔形成するときに一緒にドリルでもって先端部分を穿孔すれば容易である。
なお、図２におけるブーム２の断面形状をやや楕円形に形成したが、これを真円に形成したものであっても良い。但し、仕上がった状態では、左右方向に長径側が位置する楕円形になる。また、リブ３の長さＳ１をやや短く形成してアンテナ素子６の外周面７に達するか、達しないか、の程度までに短く形成したものであっても実施は可能である。但し、仕上がった状態では、リブ３の先端側３ｂにおけるアンテナ素子６の外周面７に接する面が僅かに少なくなるが、実用面では問題は起こらない。
【００１５】
次にブーム２に装着するアンテナ素子６を固着する手段について説明する。
先ず、図２に示されるブーム２の管壁４に対して周知の手段を用いて上記二個一対の管壁孔４ａ、４ａ・・４ａを穿孔形成する。そのときには前述したようにリブ３の先端側３ｂ、３ｂのアンテナ素子６に対向させる一部分にアンテナ素子６の外周面７に対応する円弧状の凹部を一緒に形成するとよい。
次に夫々の二個一対の管壁孔４ａ、４ａ・・４ａには複数のアンテナ素子６を図１、２に示されているように貫通させる。
この場合、アンテナ素子６の両端閉塞等の必要な端面処理加工は、作業のし易い場所において、予め能率良く施しておくと、その後の加工が単純化される（複雑にならない）効果がある。
【００１６】
次に、図２（Ｂ）に示される断面形状のブーム２の外周面４に対して、上下方向から任意の手段で力を加え、ブーム２の管壁４の形状を、図３に現れているように変形させる。
この変形させる手段としては、例えば図２（Ｂ）に２点鎖線で示されているように、ブーム２を中間にして、互いに対向する状態で一対のプレス金型１１、１１を配置その金型の内側面に対して夫々ブーム２の仕上がり予定の外周形状（図３（Ｂ）のブームの仕上がり外周形状４）に対応する円弧状の凹部１２、１２を備える。
図２（Ｂ）の状態で上下二つのプレス金型１１、１１を近付けると、図２（Ｃ）の長径Ｄ１は図３（Ｃ）の長径Ｄ３のように圧縮されて縮み、短径Ｄ２は、図３（Ｃ）の短径Ｄ４のようにアンテナ素子６の軸線方向に広がる。その結果、ブーム２の管壁４の形状は、楕円形状から図３（Ｃ）のほぼ真円形状に変形する。
【００１７】
さらに、上記のように上下二つのプレス金型１１、１１を近付けると、四本のリブ３、３、３、３は、共にブーム２の管壁４の内部におけるアンテナ素子６の一部分６ａにおける管壁７に向かって押し進められる。このようにしてブーム２の管壁４における相互に対向する部分が、四本のリブ３、３、３、３と共に押し進められると、図３（Ｂ）、（Ｃ）に図示されているように、アンテナ素子の部分６ａの外周面７は、リブ３の先端側３ｂの対接部分の形状に対応した円弧の形状に凹まされる。これにより、アンテナ素子の断面形状は、図３（Ａ）に示されているように楕円形状となり、アンテナ素子の部分６ａの対応部分４箇所に谷部７ｄを備える凹部７ｂが構成される。
また各谷部７ｄには上記リブ３の先端３ｂが喰い込み状態で圧接し、アンテナ素子の部分６ａにおける断面形状が、凹部７ｂの位置では楕円形状になっているが為に、そこでは回り止め効果が発揮される。また凹部７ｂの前後の両傾斜面においては、アンテナ素子の部分６ａが図３（Ｂ）の左右方向へ移動することを防止する。このように、リブ３の先端３ｂと凹部７ｂとの嵌合により、中空管状のアンテナ素子６ａの回動と、アンテナ素子６の長手方向への移動は阻止され、上記ブーム２にアンテナ素子６は固着されることになる。
【００１８】
上記の図２（Ｂ）に示されている上下二つのプレス金型１１、１１の奥行き方向の長さは、ブーム２の長さに対応させた寸法であればプレス作業の能率は極めて良好となる。しかしそれよりも著しく短くても、ブーム２の長手方向に向けてのプレスを複数回繰返しても実施が可能になる。上下に作動する二つのプレス金型１１、１１に代えて、上下に加圧ローラーを配し、その間にブーム２を相対移動させることによっても、ブーム２を上下から加圧して変形させることが可能である。
【００１９】
なお一般的なブームとアンテナ素子の寸法関係は、図２に示される変形前の状態においては、ブーム（アルミ）２の外径は、Ｄ１：２３ｍｍ、Ｄ２：２１ｍｍ、ブーム２の肉厚寸法は：１．０ｍｍ、ブームの管壁の貫通孔の内径は：８．１ｍｍ、アンテナ素子（アルミ）の外径は：８ｍｍ、アンテナ素子の内径は：７ｍｍが妥当な寸法。
次にリブ３の寸法関係は、それらと、アンテナ素子の管壁の厚み状態との相関関係によって多少は異なるが、あえて例示すれば、図２（Ｂ）においてリブ３における管壁外周面から先端３ｂまでの突出寸法Ｓ１は：８ｍｍ、先端３ｂ、３ｂ相互間のＳ２は：７ｍｍ、リブ３における厚みは：１．０ｍｍ、リブ３、３の相互間の幅Ｌ１は：１１ｍｍに設定してある。
次に、図３に示される変形後の状態においては、ブーム（アルミ）２の外径は、Ｄ３：２２ｍｍ、Ｄ４：２２ｍｍに変化して真円に近い形状になる。
また、先端３ｂ、３ｂ相互間のＳ３は：６ｍｍに縮まり、先端３ｂ、３ｂはアンテナ素子の管壁に０．５ｍｍ位喰い込み、アンテナ素子の管壁を保持する。また前述したようアンテナ素子の部分６ａは横に張り出し、図３（Ａ）の如く楕円形状になって、回止め作用を発揮する。
しかし以上記載した寸法は、アンテナの用途が異なることによって、ブームの大きさ、アンテナ素子の寸法などが変更される為、それに伴い夫々の寸法は対応して変更しなければならない。
【００２０】
次に、図４の（Ａ）、（Ｂ）に示されるものは、図３のリブ３とは異なる状態を示すものである。
（Ａ）は、減径させたブーム２の内部において、アンテナ素子６に対して直交させた状態で中心位置に夫々一本のリブ３、３を配置した例を示す。（Ａ）に示されているブーム２と、アンテナ素子６と、リブ３に対する加圧の加工に伴う状態変化に係わる技術的事項は、前述した図１〜図３について説明したと同じような内容であるから重複する説明ば省略する。
また（Ｂ）に示されるものは、ブーム２の横断面形状を、図３（Ｃ）に示される丸形のものとは異なる多角形の例として示すものである。この形状のものも、図２，３の各（Ｂ）（Ｃ）及び図４の（Ａ）に示され場合と同様に、ブーム２の横断面形状を予めやや大きく（２点鎖線２ｄで示されている程度に大きく）形成しておき、アンテナ素子６を貫通させた後に、外部の両側から相対的に矢印１５方向に向けての圧縮力を加えて、リブ３の先端３ｂをアンテナ素子６の周壁に喰い込ませ、回り止めと、抜け止め効果が発揮できるようにしてある。
以上のように図４の（Ａ）、（Ｂ）に示されるものも、リブにおける元部側３ｃから自由端側３ｂに向けての方向は、上記存置予定位置に置かれるアンテナ素子６の軸線に対して交差する方向に設定してあり、リブ３、３は夫々アンテナ素子６の中央部６ａに向け、直交状態、又は少し傾斜させた状態で、互いに伸びており、中央部６ａにおいては上下からアンテナ素子６を押圧し、その押し圧によって中空管状のアンテナ素子における一部分６ａの外周面７を凹ませ、リブの自由端３ｂと中空管状のアンテナ素子の外周面７における凹部７ｂとを嵌合させる。この嵌合により、中空管状のアンテナ素子の回動と、アンテナ素子の長手方向への移動を阻止するようにしたものである。
なお、図４において前述の図２、３の場合と機能、性質又は特徴等が同一又は均等構成と考えられる部分には、前述の図２、３と同一の符号を付して重複する説明を省略する。
【００２１】
【発明の効果】
本願発明は、ブーム２の管内に位置するアンテナ素子の部分６ａにおいて、ブーム２の管壁４における管壁孔４ａから離れた位置に設けられている凹部７ｂ、７ｂに対して、元部側３ｃが夫々管壁４に一体的に固着してあるリブ３の自由端３ｂを夫々当接させて上記アンテナ素子の部分６ａを両側から挟持する状態で、上記ブーム２にアンテナ素子６を固着するものであるから、中空のブーム２に対し、アンテナ素子６を固定した状態においては、それの固定部分７ｂ、３ｂが外部からは見ることができず、外観的に美しい状態で固着されたアンテナを提供できる効果がある。
【００２２】
その上本願発明にあっては、上記のように構成したことによって、アンテナが暴風雨に晒されて、アンテナ素子６が暴風雨による振動を受けたとき、上記の固着部分７ｂ，３ｂは、ブーム２の管内の中央寄り位置にあって管壁４により守られており、ブーム２の二つの孔縁４ｂ、４ｂがアンテナ素子６の固着部分７ａ、３ｂの振れによる折損を防ぐ為の支柱の役割を果たす効果がある。
本件発明にあってはこのようにして、アンテナ素子６の全体の共振現象を柔らかなものにし、アンテナ素子６におけるブームの管壁の孔縁４ｂ、４ｂ近くの損傷を防いで、アンテナ素子６の寿命を高めることのできる効果がある。
【００２３】
更に本願発明にあっては、前述したようにブーム２の管内に位置するアンテナ素子部分６ａにおいて、ブーム２の管壁４における管壁孔４ａから離れた位置に設けられている凹部７ｂ、７ｂに対して、元部側が夫々管壁４に一体的に固着してあるリブ３の自由端３ｂを夫々当接させ、上記アンテナ素子の部分６ａを両側から挟持する状態で、上記ブーム２にアンテナ素子６を固着する構成であるから、固着部分７ｂ、３ｂの位置は、加工精度上、両側の管壁孔４ａ、４ａから適当な寸法だけ離れた任意の位置に自由に選定できる特徴がある。これにより、固着部分７ｂ、３ｂを構成する技術精度は安易なものでよく、手軽でかつ能率よく構成できる効果がある。
【００２４】
さらに本願発明にあっては、二個一対の管壁孔に夫々中空管状のアンテナ素子を貫通させた後、上記固着部分７ｂ、３ｂを構成するに当っては、予めリブ３の元部側は管壁４に一体的に固着しておき、リブ３の先端側３ｂは自由端に構成し、しかもリブ３における元部側３ｃから先端側３ｂに向けての方向は、上記存置予定位置に置かれるアンテナ素子６の軸線に対して交差する方向に設定したことにより、単純に上記ブームの管壁４を変形させて、ブーム管内の上記リブ３の自由端３ｂを上記中空管状アンテナ素子の管壁７に押し当てる操作でもって、中空管状のアンテナ素子の外周面７に凹部７ｂを形成し、同時にリブの自由端３ｂと嵌合させることができるという、単純加工を可能にする優れた特徴がある。
このことは、上記の中空管状アンテナ素子の管壁７に、ブーム管内の上記リブ３の先端側３ｂを当て付ける為に、ブーム管内において、特別の工具を用いてリブ３に曲げ加工施すなどの特別な配慮を要すること無くして、手軽に固着作業が行えるという、作業上誠に優れた効果がある。
【図面の簡単な説明】
【図１】アンテナの斜視図。
【図２】（Ａ）は、図１におけるブーム管壁変形前のＩＩ−ＩＩ線位置断面図、（Ｂ）は、（Ａ）図のＩＩＩ’−ＩＩＩ’線断面図、（Ｃ）は、（Ａ）図のＩＶ’ーＩＶ’線断面図。
【図３】（Ａ）は、図１におけるＩＩ−ＩＩ線断面図、（Ｂ）は、（Ａ）図のＩＩＩーＩＩＩ線断面図、（Ｃ）は、（Ａ）図のＩＶ−ＩＶ線断面図。
【図４】図３（Ｃ）に示されるリブとは異なる実施例を示す断面図。
【図５】従来において、ブームの内側に位置するアンテナ素子の一部を膨出させる為の手段の一例を示す為の図面であって、（Ａ）は、膨出加工寸前の状態を示す縦断面図。（Ｂ）はブームの管壁内面の間際を膨出させた状態を示す縦断面図。
【符号の説明】
１・・・アンテナ、２・・・ブーム（アーム）、３・・・リブ、４・・・ブームの管壁、４ａ・・・ブームの管壁孔、４ｂ・・・ブームの管壁の孔縁、６・・・アンテナ素子（導波素子）、７・・・アンテナ素子の管壁、７ａ・・・アンテナ素子の膨出部、７ｂ・・・アンテナ素子の凹部、８・・・放射器、９・・・反射器、１０・・・導波器、１１・・・金型、１２・・・金型の内面。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a plurality of through holes at appropriate intervals in the axial direction of the boom when transmitting and receiving UHF and other communication signals, for example. The present invention relates to an antenna of a type in which an element is fixed and used while penetrating an element.
[0002]
[Prior art]
Conventionally, a plurality of through holes oriented in a direction orthogonal to the axis of the boom are provided at positions at appropriate intervals in the axial direction of the boom, and each of the plurality of through holes is provided. An antenna in which a pipe-shaped antenna element is penetrated, and these antenna elements are fixed to a boom, respectively, and a method of manufacturing such an antenna are widely known (for example, see Patent Document 1).
The above-mentioned conventional fixing means inserts a metal hollow tube made of a plastic material into the tube of the antenna element, positions it around the axis of the boom, and places a rod-shaped jig from both sides in the hollow tube. By inserting the tip of the boom and applying pressure from both sides, the entrance of the hollow tube is deformed in the radial direction, and the entire circumference of the tube wall in the boom in the antenna element is expanded in the radial direction by the deformation action, so that the boom Means for fixing the antenna element to the boom by pressing against the inner edge of the through hole is used.
[0003]
[Patent Document 1]
JP-A-57-115001 (FIGS. 3 and 6)
[Patent Document 2]
Japanese Utility Model Publication No. 57-2707 (FIG. 3)
[0004]
[Problems to be solved by the invention]
In this conventional method of manufacturing an antenna, the degree of expansion of the ports at both ends of the hollow tube is greater than the degree of expansion at the center of the hollow tube, and inevitably, the hole in the tube wall in the boom of the antenna element. The tube wall near the edge is locally expanded radially at a sharp angle. When a part of the tube wall is locally expanded in this way, there is a problem that durability is lacked, for example, due to repeated use, the tube wall is repeatedly damaged by repeated use of the load and is damaged. In addition, since one hollow tube is required as a consumable for one antenna element, there is also a problem that the cost of parts is increased and the production cost is increased.
In order to save the above consumables, there is a means shown in FIG. 5 as a means for mechanically expanding a tube wall near a hole edge in a tube wall in a boom of an antenna element without using consumables (for example, FIG. 5). , Patent Document 2).
[0005]
In the antenna manufactured by such a known means, at the time of manufacturing, the operation of penetrating the antenna element 6 into the tube of the boom 2 and fixing the antenna element 6 to the boom 2 is performed by each of the rod-shaped jigs 14, 14. The opposed surfaces 15, 15 in the inclined state at the distal ends are in the preparation state of FIG. 5A, and the opposed surfaces 15, 15 in the inclined state at the respective distal ends of the rod-shaped jigs 14, 14 are shown in FIG. Advance from both sides to position B). Then, the overlap between the opposed surfaces 15 and 15 in the inclined state increases, so that the outer periphery of the overlapping portion of the opposed surfaces 15 and 15 increases, and the inner diameter of the antenna element 6 expands as illustrated. However, when dust 16 is interposed between the opposing surfaces 15, 15 in such work, the outer circumference of the overlapping portion of the opposing surfaces 15, 15 becomes larger than a predetermined dimension, and as shown in FIG. There is a problem that the bulging amount of the bulging portion 7a to be formed near 4b protrudes larger than expected and damages the tube wall 7 of the antenna element 6 near the hole edge 4b of the tube wall of the boom.
Further, when the overlapping of the opposed surfaces 15 and 15 in the inclined state is smaller than expected, the bulging portion 7a of the antenna element 6 does not protrude near the hole edge 4b of the tube wall of the boom 2 and is higher than the expected location. A bulging portion 7a protrudes toward an intermediate portion in the tube of the boom 2. Then, the bulging portion 7a is separated without contacting the inside of the hole edge 4b of the boom, and the antenna element is not fixed, is displaced in the axial direction, and has a problem of increasing the defective product occurrence rate.
[0006]
Moreover, even if the bulging portion 7a protrudes near the hole edge 4b of the tube wall of the boom 2 and the antenna element 6 is fixed, the antenna is exposed to storm and the boom 2 and the antenna element 6 are When receiving the vibration due to the storm, the antenna element projecting from the boom 2 vibrates around the bulging portion 7a near the hole edge 4b of the boom tube wall as a fulcrum.
This means that the antenna element is repeatedly subjected to a bending load with the fulcrum near the weakened bulging portion 7a due to the resonance phenomenon, and the tube wall of the antenna element is locally damaged by metal fatigue near the bulging portion 7a. There was a problem that it was damaged and broken.
[0007]
The antenna of the present application is provided to solve the above-mentioned problems of the related art.
An object of the present application is to provide an antenna in which a fixed portion cannot be seen from the outside in a state where an antenna element is fixed to a hollow boom, and the antenna element is fixed in a beautiful appearance. .
Another object of the present application is that even when the antenna is exposed to a storm and the antenna element is subjected to a resonant vibration due to the storm, the fixed portion at the base of the antenna element protruding from the boom is not significantly affected. In the boom tube, the boom tube is set at a position near the middle away from the tube wall hole. An object of the present invention is to provide an antenna capable of softening the phenomenon, preventing damage near the hole of the boom tube wall in the antenna element, and extending the life of the antenna element.
[0008]
Another object of the present application is to penetrate the antenna element into the boom and fix the antenna element to the boom, as in the related art, where the fixing place may be limited near the hole edge of the inner wall of the boom. The antenna has a wide selection range of the fixing position of the antenna element in the boom, and it is possible to select the coupling position of the two with rough processing accuracy. It is what we are going to offer.
Another object of the present application is to allow the antenna element to penetrate through the boom and fix the antenna element to the boom, by simply deforming the tube wall of the boom and setting the free end of the rib in the boom tube to a hollow tubular antenna. An object of the present invention is to provide an antenna in which a concave portion is formed on an outer peripheral surface of a hollow tubular antenna element by an operation of pressing against a tube wall of the element, and at the same time, a free end of a rib can be fitted.
Other objects and advantages will become more readily apparent from the drawings and the following description associated therewith.
[0009]
[Means for Solving the Problems]
The antenna according to the invention of the present application is a pair of two antennas for penetrating hollow tubular antenna elements in a direction perpendicular to the axis of the boom, respectively, at an appropriate distance in the axial direction on the tube wall of the hollow boom. An antenna having a plurality of tube wall holes, a hollow tubular antenna element penetrating each of the pair of tube wall holes, and the antenna elements are respectively fixed to the boom. The fixation of the element is a portion located in the boom tube of the hollow tubular antenna element, and a concave portion on each side of the peripheral surface of the antenna element at a position away from the tube wall hole in the tube wall of the boom. On the other hand, in the boom tube, on the other hand, ribs extending in the axial direction of the boom are provided on both sides of the antenna element in the cross-sectional shape with the antenna element in the middle, The base portions of the ribs in the cross-sectional shape are integrally fixed to the tube wall of the boom, respectively, and the direction of the ribs from the base portion toward the free end is set at the above-mentioned expected position. The free end side of each rib is set in a direction intersecting with the axis of the antenna element, and the free end side of each rib is positioned with respect to the axis of the antenna element with respect to the valleys of the concave portions formed on both sides of the tube wall of the antenna element. The antenna element is fixed to the boom in a state where the antenna element is abutted in a state where the antenna element is pressed from an intersecting direction and the antenna element is sandwiched from both sides.
[0010]
Preferably, the hollow boom tube wall is provided with a pair of two tube walls for allowing the hollow tubular antenna elements to pass through in a direction orthogonal to the boom axis at an appropriate distance in the axial direction. A plurality of holes, a hollow tubular antenna element penetrates each of the pair of tube wall holes, and the antenna elements are respectively fixed to the boom. The fixed portion is a portion of the hollow tubular antenna element that is located inside the boom tube, and a concave portion is formed on each side of the peripheral surface of the antenna element that is away from the tube wall hole in the tube wall of the boom. To multiple locations in a state where they are separated from each other,
In the tube of the boom, a plurality of ribs each extending in the axial direction of the boom are provided in parallel on both sides of the antenna element in the cross-sectional shape with the antenna element in the middle, and in the cross-sectional shape of those ribs. The base portion side is integrally fixed to the tube wall on the side of the tube wall hole, respectively, and the direction of the respective ribs from the base portion side to the free end side is the antenna element placed at the above-mentioned expected position. In the direction intersecting with the axis of the antenna element, the free end side of each rib intersects with the axis of the antenna element with respect to the valleys of the concave portions formed on both sides of the tube wall of the antenna element. The antenna element is fixed to the boom in a state where the antenna element is brought into contact with the boom while pressing the antenna element from a plurality of positions on both sides.
[0011]
Also preferably, the hollow boom is provided with ribs extending in the axial direction of the boom inside the hollow boom at positions on both sides of the expected position of the antenna element in a cross-sectional shape. Are fixed integrally to the tube wall of the boom, and the leading end side in the cross-sectional shape of each rib is a free end. It is set in a direction intersecting the axis of the antenna element placed at the position, and the boom has a hollow tubular antenna element orthogonal to the axis of the boom at an appropriate distance in the axial direction. A pair of two tube wall holes for penetrating in the direction are provided, and then the hollow tubular antenna element is penetrated through the pair of tube wall holes, and the antenna element is placed at the expected position. ,next By deforming the tube wall of the boom, the free end of the rib in the boom tube is pressed against the tube wall of the hollow tubular antenna element, and the outer peripheral surface of the hollow tubular antenna element is depressed. It is sufficient if the outer circumferential surface of the antenna element is fitted to the concave portion to prevent the rotation of the hollow tubular antenna element and the movement of the antenna element in the longitudinal direction.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, drawings illustrating embodiments of the present invention will be described. 1 to 3, reference numeral 1 denotes a well-known antenna used for transmitting and receiving arbitrary communication signals (including image signals) such as VHF to UHF waves. Reference numeral 2 denotes a hollow boom having a circular cross section (or a polygonal shape including a hexagon as shown in FIG. 4) formed of aluminum or a plastically deformable hard material, etc., as is well known. It is mounted above the mast 1a established in the above, and is arranged in the direction of transmission and reception of communication.
In the axial direction of the boom 2, as shown in FIG. 1, a director 10, a radiator 8, and a reflector 9 are provided at appropriate high-frequency intervals.
The boom 2 provided with the director 10 is provided with a plurality of through holes 4a at appropriate intervals in a direction orthogonal to the axis of the boom 2.
The through hole 4a formed in the tube wall 4 of the hollow boom 2 is a pair of two tube wall holes 4a for allowing the hollow tubular antenna element 6 to penetrate in a direction perpendicular to the axis of the boom.
[0013]
Inside the hollow boom 2 shown in FIG. 1, FIG. 2, FIG. 3, and FIG. 4, the antenna element 6 is placed in the middle in the sectional shape (cross section as shown in FIG. Ribs 3 extending in the axial direction of the boom 2 (the left-right direction in the vertical cross section of FIG. 2A) are provided on both sides of the lever.
The base portions 3c in the cross-sectional shape of the ribs 3 are integrally formed with the tube wall 4 by using an integral material, and are fixed.
The direction of the rib from the base side 3c to the free end side 3b intersects with the axis of the antenna element 6 placed at the expected position as shown in FIGS. The traveling direction is directed to the outer peripheral surface 7 of the antenna element 6.
The distal ends 3b, 3b in the cross-sectional shape of each rib 3 are formed at free ends. Therefore, inside the boom 2, there is a portion 6a of the antenna element 6 between the upper and lower ribs 3, 3, as shown in FIGS.
[0014]
Next, FIG. 2 shows a state before the boom tube wall deformation. The cross-sectional shape of the boom 2 is slightly elliptical, and the minor axis D2 is slightly smaller than the major axis D1. . In this state, the length S1 of the rib 3 is set to a length sufficient to reach the outer peripheral surface of the antenna element 6.
Therefore, the dimension S2 between the distal ends 3b, 3b of the opposing ribs 3, 3 is smaller than the diameter D5 of the antenna element 6. Also, from such circumstances, as shown in FIG. 2A, the portions of the distal ends 3b, 3b of the ribs 3, 3 that overlap with the outer peripheral surface 7 of the antenna element 6, as shown in FIG. Are partly removed along the outer peripheral surface 7 of the antenna element 6 in an arc shape. As a means for the deletion, for example, when the pair of two tube wall holes 4a, 4a are formed by drilling together, the distal end portion can be easily drilled.
Although the cross-sectional shape of the boom 2 in FIG. 2 is slightly elliptical, it may be formed as a perfect circle. However, in the finished state, it has an elliptical shape in which the longer diameter side is located in the left-right direction. Further, it is possible to implement even if the length S1 of the rib 3 is slightly shortened so as to reach or not reach the outer peripheral surface 7 of the antenna element 6. In the finished state, however, the surface in contact with the outer peripheral surface 7 of the antenna element 6 on the distal end side 3b of the rib 3 is slightly reduced, but no problem occurs in practical use.
[0015]
Next, means for fixing the antenna element 6 to be attached to the boom 2 will be described.
First, a pair of the two tube wall holes 4a, 4a,... 4a is formed by drilling the tube wall 4 of the boom 2 shown in FIG. At that time, as described above, it is preferable to form an arc-shaped concave portion corresponding to the outer peripheral surface 7 of the antenna element 6 at a part of the distal end side 3b, 3b of the rib 3 facing the antenna element 6.
Next, a plurality of antenna elements 6 are passed through the pair of two tube wall holes 4a, 4a,... 4a as shown in FIGS.
In this case, if the necessary end face processing such as the closing of both ends of the antenna element 6 is efficiently performed in advance in a place where the work is easy, the subsequent processing can be simplified (not complicated).
[0016]
Next, a force is applied to the outer peripheral surface 4 of the boom 2 having the cross-sectional shape shown in FIG. 2B from above and below by any means, and the shape of the tube wall 4 of the boom 2 appears in FIG. Deform as if it were.
As means for this deformation, for example, as shown by a two-dot chain line in FIG. 2 (B), a pair of press dies 11, 11 are arranged with the boom 2 in the middle and opposed to each other. And arcuate concave portions 12 corresponding to the outer peripheral shape of the boom 2 to be finished (finished outer peripheral shape 4 of the boom in FIG. 3B).
When the upper and lower press dies 11, 11 are brought close to each other in the state of FIG. 2B, the long diameter D1 of FIG. 2C is compressed and shrunk like the long diameter D3 of FIG. 3C, it spreads in the axial direction of the antenna element 6 like the short diameter D4. As a result, the shape of the tube wall 4 of the boom 2 changes from an elliptical shape to a substantially perfect circular shape shown in FIG.
[0017]
Furthermore, when the upper and lower press dies 11, 11 are brought closer to each other as described above, the four ribs 3, 3, 3, 3 are both connected to the tube 6a of the antenna element 6 inside the tube wall 4 of the boom 2. It is pushed towards the wall 7. When the mutually facing portions of the tube wall 4 of the boom 2 are pushed together with the four ribs 3, 3, 3, 3 in this manner, as shown in FIGS. 3B and 3C. The outer peripheral surface 7 of the portion 6a of the antenna element is recessed into an arc shape corresponding to the shape of the contact portion of the tip 3b of the rib 3. As a result, the cross-sectional shape of the antenna element becomes elliptical as shown in FIG. 3A, and a concave portion 7b having a valley 7d at four corresponding portions of the portion 6a of the antenna element is formed.
Further, the tip 3b of the rib 3 is pressed against each valley 7d in a biting state, and the cross-sectional shape of the portion 6a of the antenna element is elliptical at the position of the recess 7b. The effect is exhibited. Further, on both inclined surfaces before and after the concave portion 7b, the portion 6a of the antenna element is prevented from moving in the left-right direction in FIG. 3B. Thus, the fitting of the tip 3b of the rib 3 and the recess 7b prevents the rotation of the hollow tubular antenna element 6a and the movement of the antenna element 6 in the longitudinal direction. It will be fixed.
[0018]
If the length in the depth direction of the upper and lower two press dies 11, 11 shown in FIG. 2B is a dimension corresponding to the length of the boom 2, the efficiency of the press work is extremely good. Become. However, even if it is significantly shorter than that, it becomes possible to carry out the pressing operation in the longitudinal direction of the boom 2 a plurality of times. The boom 2 can be deformed by pressing the boom 2 from above and below by disposing a pressurizing roller above and below instead of the two press dies 11 and 11 operating vertically. It is.
[0019]
Note that the general relationship between the boom and the antenna element is as follows: in the state before deformation shown in FIG. 2, the outer diameter of the boom (aluminum) 2 is D1: 23 mm, D2: 21 mm, and the thickness of the boom 2 is : 1.0 mm, the inside diameter of the through hole in the tube wall of the boom is 8.1 mm, the outside diameter of the antenna element (aluminum) is 8 mm, and the inside diameter of the antenna element is 7 mm.
Next, the dimensional relationship of the ribs 3 is slightly different depending on the correlation between them and the thickness state of the tube wall of the antenna element. However, as an example, in FIG. The protruding dimension S1 up to 3b is set to: 8 mm, the S2 between the tips 3b and 3b is set to 7 mm, the thickness at the rib 3 is set to 1.0 mm, and the width L1 between the ribs 3 and 3 is set to 11 mm. .
Next, in the state after the deformation shown in FIG. 3, the outer diameter of the boom (aluminum) 2 changes to D3: 22 mm and D4: 22 mm, and becomes a shape close to a perfect circle.
Further, S3 between the tips 3b and 3b is reduced to 6 mm, and the tips 3b and 3b bite into the tube wall of the antenna element by about 0.5 mm to hold the tube wall of the antenna element. Further, as described above, the portion 6a of the antenna element projects laterally and becomes an elliptical shape as shown in FIG.
However, in the dimensions described above, the size of the boom, the dimensions of the antenna element, and the like are changed depending on the use of the antenna, and accordingly, each dimension must be changed accordingly.
[0020]
Next, FIGS. 4A and 4B show a state different from the rib 3 in FIG.
(A) shows an example in which one rib 3, 3 is arranged at the center position in a state of being orthogonal to the antenna element 6 inside the boom 2 whose diameter has been reduced. The technical items related to the state change accompanying the pressing of the boom 2, the antenna element 6, and the rib 3 shown in (A) are the same as those described with reference to FIGS. Therefore, repeated description will be omitted.
FIG. 3B shows the cross-sectional shape of the boom 2 as an example of a polygon different from the round shape shown in FIG. 3C. Also in this shape, the cross-sectional shape of the boom 2 is made slightly larger in advance (shown by a two-dot chain line 2d) as in the cases shown in FIGS. 2B and 3C and FIG. 4A. After the antenna element 6 is penetrated, a compressive force is applied relatively from both sides on the outside in the direction of the arrow 15 so that the tip 3 b of the rib 3 is moved to the antenna element 6. To prevent it from turning and to prevent it from slipping out.
4A and 4B, the direction of the rib from the base side 3c to the free end side 3b is the axis of the antenna element 6 placed at the above-mentioned expected position. And the ribs 3 extend toward the center 6a of the antenna element 6 in an orthogonal state or a slightly inclined state. , The outer peripheral surface 7 of the portion 6a of the hollow tubular antenna element is depressed by the pressing force, and the free end 3b of the rib is fitted to the concave portion 7b of the outer peripheral surface 7 of the hollow tubular antenna element. Let it. This fitting prevents rotation of the hollow tubular antenna element and movement of the antenna element in the longitudinal direction.
In FIG. 4, portions that are considered to have the same or equivalent functions, properties, or characteristics as those in FIGS. 2 and 3 described above are given the same reference numerals as in FIGS. Omitted.
[0021]
【The invention's effect】
According to the present invention, in the portion 6a of the antenna element located in the tube of the boom 2, the concave portion 7b, 7b provided at a position away from the tube wall hole 4a in the tube wall 4 of the boom 2 is located at the base portion side 3c. Affixing the antenna element 6 to the boom 2 in a state where the free ends 3b of the ribs 3 integrally fixed to the tube wall 4 are respectively brought into contact with each other and the antenna element portion 6a is sandwiched from both sides. Therefore, when the antenna element 6 is fixed to the hollow boom 2, the fixed portions 7b and 3b thereof cannot be seen from outside, and the antenna is fixed in a beautiful appearance. There is an effect that can be done.
[0022]
In addition, according to the present invention, when the antenna is exposed to the storm and the antenna element 6 is vibrated by the storm, the fixing portions 7b and 3b of the boom 2 are connected to the antenna. It is located near the center of the pipe and is protected by the pipe wall 4, and the two hole edges 4b and 4b of the boom 2 play a role as a support for preventing breakage due to deflection of the fixed portions 7a and 3b of the antenna element 6. effective.
Thus, in the present invention, the whole resonance phenomenon of the antenna element 6 is softened, damage of the antenna element 6 near the hole edges 4b, 4b of the boom tube wall is prevented, and the antenna element 6 is prevented from being damaged. This has the effect of extending the life.
[0023]
Further, in the present invention, as described above, in the antenna element portion 6a located in the tube of the boom 2, the concave portions 7b, 7b provided at positions away from the tube wall holes 4a in the tube wall 4 of the boom 2 are provided. On the other hand, the free ends 3b of the ribs 3 whose base portions are integrally fixed to the pipe wall 4 are respectively brought into contact with each other, and the antenna element 6 is held on both sides of the boom 2 while the antenna element portion 6a is sandwiched from both sides. 6, the position of the fixed portions 7b, 3b can be freely selected at an arbitrary distance from the tube wall holes 4a, 4a on both sides by an appropriate dimension in terms of processing accuracy. Thus, the technical accuracy for forming the fixing portions 7b and 3b may be simple, and there is an effect that the fixing portions 7b and 3b can be easily and efficiently configured.
[0024]
Further, in the present invention, after the hollow tubular antenna elements are respectively penetrated into the pair of tube wall holes, the base portions of the ribs 3 are previously The distal end 3b of the rib 3 is configured to be a free end, and the direction of the rib 3 from the base 3c to the distal end 3b is set at the above-mentioned expected position. By setting the direction perpendicular to the axis of the antenna element 6 to be cut, the tube wall 4 of the boom is simply deformed, and the free end 3b of the rib 3 in the boom tube is connected to the tube wall of the hollow tubular antenna element. The recess 7b is formed in the outer peripheral surface 7 of the hollow tubular antenna element by the operation of pressing against the rib 7 and can be fitted to the free end 3b of the rib at the same time. .
This means that the rib 3 is bent using a special tool in the boom tube so that the distal end 3b of the rib 3 in the boom tube is applied to the tube wall 7 of the hollow tubular antenna element. There is an excellent effect on work that the fixing work can be easily performed without requiring special consideration.
[Brief description of the drawings]
FIG. 1 is a perspective view of an antenna.
2 (A) is a sectional view taken along the line II-II of FIG. 1 before boom tube wall deformation, FIG. 2 (B) is a sectional view taken along the line III′-III ′ of FIG. 1 (A), and FIG. FIG. 4A is a sectional view taken along the line IV′-IV ′ in FIG.
3A is a sectional view taken along line II-II in FIG. 1, FIG. 3B is a sectional view taken along line III-III in FIG. 1A, and FIG. 3C is a sectional view taken along line IV-IV in FIG. Sectional view.
FIG. 4 is a sectional view showing an embodiment different from the rib shown in FIG. 3 (C).
FIG. 5 is a view showing an example of a conventional means for expanding a part of an antenna element located inside a boom, and FIG. 5 (A) is a longitudinal section showing a state immediately before the expansion processing. Area view. (B) is a longitudinal cross-sectional view showing a state in which the boom is bulged to a point near the inner surface of the tube wall.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 ... Boom (arm), 3 ... Rib, 4 ... Boom tube wall, 4a ... Boom tube wall hole, 4b ... Boom tube wall hole Edge, 6: antenna element (waveguide element), 7: tube wall of antenna element, 7a: bulge of antenna element, 7b: recess of antenna element, 8: radiator , 9: reflector, 10: director, 11: mold, 12: inner surface of mold.

Claims

The tube wall of the hollow boom is provided with a plurality of two pairs of tube wall holes for allowing hollow tubular antenna elements to penetrate in a direction perpendicular to the axis of the boom, respectively, at appropriate intervals in the axial direction. ,
In each of the pair of two tube wall holes, a hollow tubular antenna element is penetrated, and the antenna elements are respectively fixed to the boom.
The fixation of the antenna element to the boom,
In the hollow tubular antenna element, a portion located in a boom tube, and a concave portion is formed on both sides of a peripheral surface of the antenna element at a position apart from a tube wall hole in a tube wall of the boom, ,
In the tube of the boom, a rib extending in the axial direction of the boom is provided on each side position of the antenna element in the cross-sectional shape with the antenna element in the middle, and
The base portions in the cross-sectional shapes of the ribs are integrally fixed to the tube wall of the boom, respectively.
The direction from the base to the free end of the rib is set so as to intersect with the axis of the antenna element placed at the expected position.
The free end sides of the respective ribs are brought into contact with the valleys of the concave portions formed on both sides of the tube wall of the antenna element in a state where the ribs are pressed from a direction intersecting the axis of the antenna element. An antenna, wherein an antenna element is fixed to the boom while holding the element from both sides.

The tube wall of the hollow boom is provided with a plurality of two pairs of tube wall holes for allowing hollow tubular antenna elements to penetrate in a direction perpendicular to the axis of the boom, respectively, at appropriate intervals in the axial direction. ,
In each of the pair of two tube wall holes, a hollow tubular antenna element is penetrated, and the antenna elements are respectively fixed to the boom.
The fixation of the antenna element to the boom,
In the hollow tubular antenna element, a portion located inside the boom tube, and on both sides of the peripheral surface of the antenna element at a position distant from the tube wall hole in the tube wall of the boom, concave portions are respectively separated from each other. In the boom tube, on the other hand, a plurality of ribs extending in the axial direction of the boom are arranged in parallel on both sides of the antenna element in the cross-sectional shape with the antenna element in the middle. Prepared, and
The base portions in the cross-sectional shape of the ribs are integrally fixed to the tube wall on the tube wall hole side, respectively, and the direction from the base portion side to the free end side of each rib is the same as Set in a direction that intersects the axis of the antenna element placed at the scheduled position,
The free end sides of the respective ribs are brought into contact with the valleys of the concave portions formed on both sides of the tube wall of the antenna element in a state where the ribs are pressed from a direction intersecting the axis of the antenna element. An antenna, wherein an antenna element is fixed to the boom in a state where the element is sandwiched from a plurality of places on both sides.

The hollow boom is provided with ribs extending in the axial direction of the boom at positions inside the hollow boom on both sides of the expected position of the antenna element in a cross-sectional shape,
The bases of the ribs in the cross-sectional shape are integrally fixed to the tube wall of the boom, and the distal ends of the ribs in the cross-sectional shape are free ends, and the ribs extend from the base toward the distal end. The direction is set in a direction that intersects the axis of the antenna element placed at the expected location,
Further, the boom is provided with a plurality of two pairs of tube wall holes for allowing the hollow tubular antenna element to penetrate in a direction orthogonal to the axis of the boom, at an appropriate interval in the axial direction,
Next, the hollow tubular antenna elements are respectively pierced through the pair of two tube wall holes, and the antenna elements are placed at the expected positions, and
Next, the tube wall of the boom is deformed, the free end of the rib in the boom tube is pressed against the tube wall of the hollow tubular antenna element, the outer peripheral surface of the hollow tubular antenna element is dented, and the free end of the rib is removed. A method of manufacturing an antenna, characterized in that rotation of the hollow tubular antenna element and movement of the antenna element in the longitudinal direction are prevented by fitting of the hollow tubular antenna element with a concave portion on the outer peripheral surface of the hollow tubular antenna element.