JP2004354911A

JP2004354911A - Flat display device

Info

Publication number: JP2004354911A
Application number: JP2003155294A
Authority: JP
Inventors: Norio Yamamoto; 則夫山本; Seiji Morimoto; 誠治森本; Taiji Nakagawa; 泰二中川; Ichiro Yamane; 一郎山根; Mitsuto Kobayashi; 光人小林
Original assignee: Tokyo Sanyo Electric Co Ltd; Tottori Sanyo Electric Co Ltd; Sanyo Electric Co Ltd
Current assignee: Tokyo Sanyo Electric Co Ltd; Sanyo Electric Co Ltd
Priority date: 2003-05-30
Filing date: 2003-05-30
Publication date: 2004-12-16
Anticipated expiration: 2023-05-30
Also published as: JP4300879B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat display device which has its circuit board properly protected even when it is used without being put in a housing and which is free of the possibility that the temperature of the circuit board and display device itself rise. <P>SOLUTION: A choice can be made between a 1st state in which an inverter circuit board 6 is fixed directly to the reverse surface 1 of a liquid crystal display panel and a 2nd state in which the inverter circuit board is fixed across a specified gap by using a member 13 for fixation. In the 2nd state, the member 13 for fixation is provided slidably in the inserting direction of the inverter circuit board 6. After the inverter circuit board 6 is inserted into a clamp part 16 of the member 13 for fixation, a protecting member 24 is mounted to fix the inverter circuit board 6 to the reverse surface 1 of the liquid crystal panel in parallel across the specified gap. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、液晶表示素子等を用いた平面表示装置に関するものである。
【０００２】
【従来の技術】
大型テレビなどにＬＣＤを用いた平面表示装置が広く用いられ、４０インチの大型の表示装置も開発されている。ＬＣＤを用いた平面表示装置は、対向する一対の電極基板の間に液晶を封入した液晶表示素子及び液晶表示素子を裏面から照明するバックライト装置から成る液晶表示パネルと、液晶表示パネルの駆動に用いられる各種の回路基板から構成される。これらの平面表示装置は通常テレビやモニターなどの筐体に組み込まれて使用されるため、液晶表示パネルの裏面に配置される各種の回路基板周辺はユーザが直接触れるおそれはなく、従来インバータ回路基板は液晶表示パネルの裏面に直接固定され、ポリエチレンテレフタレート（ＰＥＴ）製のカバーにより表面が保護されていた。
【０００３】
近年、平面表示装置の薄型化、軽量化の要求が強くなり、液晶表示パネルの裏面にシステムボードなどを付設し、筐体に組み込まずに使用する平面表示装置が提案されている。この場合、液晶表示パネルが筐体に組み込まれていないため、従来のＰＥＴ製の保護カバーでは強度的に不十分であり、またユーザが裏面の基板等に手を触れることも考えられるが、インバータ回路基板は使用時に高温となるため危険である。
【０００４】
そこで、インバータ回路基板を金属製のカバーで保護することが考えられる。裏面にリアフレームを備えた平面表示装置において、インバータ回路基板をリアフレームの内側に直接固定し、平面表示装置の薄型化、軽量化、低コスト化を図る方法が開示されている（例えば、特許文献１参照）。
【０００５】
【特許文献１】
特開２００１−３３７６２１号公報
【０００６】
【発明が解決しようとする課題】
しかしながら、特許文献１に記載の方法では平面表示装置のリアフレームにインバータ回路基板を直接固定するため、使用時にリアフレームがインバータ回路基板の発熱により高温となり危険である。また、更なる薄型化、軽量化を実現するためリアフレームを用いない構成とすることも考えられるが、この場合にはインバータ回路基板の固定が困難となる。
【０００７】
本発明は、上記の問題点に鑑み、液晶表示パネルを筐体に組み込まずに使用する平面表示装置においてもインバータ回路基板が適切に保護され、且つ表示装置自体の温度上昇の心配もない平面表示装置を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記課題を達成するため、本発明は、平面状の表示手段と、前記表示手段の駆動に用いられる回路基板と、前記回路基板を保護する保護部材と、を備えた平面表示装置において、前記回路基板を前記表示手段の裏面に設けられた押さえ片を用いて前記裏面に直接取り付ける第１の状態と、前記表示手段の裏面に着脱可能な固定用部材を介して取り付ける第２の状態を選択自在であり、前記第２の状態では前記第１の状態に比べて前記回路基板と前記表示手段の裏面との間隔が広いことを特徴とする。
【０００９】
この構成によると、平面表示装置を筐体に組み込んで使用する場合にはユーザが回路基板周辺に触れるおそれがないため、回路基板を表示手段の裏面に直接取り付ける第１の状態を選択し、筐体に組み込まずに使用する場合には回路基板周辺の温度が上昇しないように、回路基板を表示手段の裏面に固定用部材を介して表示手段の裏面との間隔を広げて取り付ける第２の状態を選択することができる。また、固定用部材を着脱可能とすることにより、固定用部材を付属させておくだけで、回路基板の取り付け方法を用途に合わせて組み立て時に適宜選択可能となる。
【００１０】
また本発明は、上記構成の平面表示装置において、前記第２の状態においては、前記回路基板の対向する二辺のうち一方は前記表示手段の裏面に立設されたスペーサにビス固定され、他方は狭持部を有する細長状の固定用部材により狭持されることとした。
【００１１】
この構成によると、第２の状態において簡易な構造の固定用部材を用いて回路基板と表示手段の裏面との間隔を広くすることができる。
【００１２】
また本発明は、上記構成の平面表示装置において、前記狭持部は、前記回路基板を表裏両側から支持する支持部材から構成され、前記回路基板の裏側を支持する前記支持部材は表側を支持する前記支持部材よりも前記回路基板の挿入方向に長く形成されていることとした。
【００１３】
この構成によると、回路基板を簡易且つ確実に狭持することができ、さらに狭持部を構成する支持部材のうち回路基板の裏側を支持する前記支持部材を、表側を支持する前記支持部材よりも前記回路基板の挿入方向に長く形成したので、回路基板を固定用部材の上方向から容易に狭持させることができる。
【００１４】
また本発明は、上記構成の平面表示装置において、前記固定用部材は、前記保護部材の装着前は前記表示手段の裏面に沿って前記回路基板の挿入方向に摺動可能に保持されており、前記保護部材の装着により、前記保護部材の側面内側が前記固定用部材に当接して前記表示手段の裏面に固定されることとした。
【００１５】
この構成によると、回路基板の他端を固定した状態においても狭持部への回路基板の挿入が一層容易となり、組み立て工程における効率が良くなる。また、回路基板を保護する保護部材を取り付けることによって固定用部材を表示手段の裏面に固定するため、固定用部材の固定手段を別途必要とせず、パーツ数も減少するためコスト面でも有利となる。
【００１６】
また本発明は、上記構成の平面表示装置において、前記第２の状態においては、前記回路基板と前記表示手段の裏面との間隔が５ｍｍ以上であることとした。これにより、回路基板及び基板周辺の温度上昇を効果的に防止することができる。
【００１７】
また本発明は、上記構成の平面表示装置において、前記表示手段は、液晶表示素子と、前記液晶表示素子を照明する照明手段とを備えた液晶表示パネルであることとした。これにより、ＬＣＤを用いた平面表示装置において、筐体に組み込まずに使用する場合に更なる薄型化、軽量化を実現し、且つ安全面でも優れた平面表示装置を提供することができる。
【００１８】
また本発明は、前記回路基板は、前記照明手段に電流を供給するインバータ回路基板であることとした。これにより、筐体やリアフレームを用いない場合でもインバータ回路基板周辺部が高温となるのを防ぎ、強度面、安全面で優れたＬＣＤを用いた平面表示装置を提供することができる。
【００１９】
【発明の実施の形態】
以下に本発明の第１実施形態を図面を参照して説明する。図１は本発明の表示手段の裏面図であり、図２は第１の状態により回路基板を取り付ける様子を示した斜視図である。なお、ここでは表示手段として、液晶表示素子と、この液晶表示素子を裏面から照明する照明手段とからなる液晶表示パネルを用い、回路基板としてインバータ回路基板を用いた場合について説明する。
【００２０】
図１において、液晶表示パネルの裏面１には回路基板をビス止めするためのビス穴２が一列に３箇所設けられ、ビス穴２の周囲は裏面１からやや突出するように形成されている。３ａ〜３ｄは第１の状態においてインバータ回路基板を狭持する押さえ片である。押さえ片３ａ〜３ｄはビス穴２の列と平行に一列に４箇所設けられ、それぞれの先端部がビス穴２の方向に向くように形成されている。
【００２１】
４は制御基板の高さを調節する突部であり、押さえ片３ａ、３ｂの間、及び押さえ片３ｃ、３ｄの間の２箇所にビス穴２と同等の高さに設けられている。押さえ片３ａ〜３ｄの下面と突部４の上面の間隔はインバータ回路基板の厚さとほぼ等しくなるように設計されている。５は液晶表示パネルの照明手段であるバックライトランプ（図示せず）とインバータ回路との接続を行うランプコネクタであり、後述するインバータ回路の出力コネクタと接続する。
【００２２】
図２において、６はインバータ回路基板であり、上面には交流電圧を直流電圧に変換するトランス７が８個設けられている。８はバックライトとインバータ回路を接続する高圧側の出力コネクタであり、ランプコネクタ５と接続される。インバータ回路基板６上のトランス７及び出力コネクタ８と反対側の端部には電源ケーブルが接続される入力コネクタ９が２箇所設けられ、照明手段の輝度を調整する調光用コネクタ１０が入力コネクタ９に隣接して１箇所設けられている。さらに出力コネクタ８側の端部にはビス穴１１が液晶パネルの裏面１のビス穴２に対応する位置に３箇所設けられている。
【００２３】
１２は低圧側の出力コネクタであり、接続ケーブルによりバックライトランプ（図示せず）に接続される。なお、インバータ回路基板６上にはチョークコイル等の他の部品や回路も存在するが、ここでは説明の便宜のため記載を省略している。第１の状態においては、インバータ回路基板６は、入力コネクタ９及び調光用コネクタ１０側の一辺が押さえ片３ａ〜３ｄと突部４との間に狭持され、反対側の一辺の端部に設けられたビス穴１１にビス（図示せず）を貫通し、裏面１に設けられたビス穴２に螺入することにより表示手段の裏面１に固定される。このときインバータ回路基板６は、ビス穴２及び突部４により裏面１に密着せず、所定の隙間を保持している。
【００２４】
次にインバータ回路基板を第２の状態により取り付ける方法について説明する。図３は第２の状態において用いられる固定用部材の斜視図であり、図４は固定用部材の平面図であり、図５は固定用部材の側面図である。図３において、固定用部材１３は、インバータ回路基板６の長手方向とほぼ同じ長さに形成され、底面部１４の４箇所には矩形の係合孔１５ａ〜１５ｄが押さえ片３ａ〜３ｄと係合する位置に設けられている。係合孔１５ａと１５ｂの間、及び１５ｃと１５ｄの間にはインバータ回路基板６を狭持する狭持部１６が底面部１４より立設されている。
【００２５】
狭持部１６はインバータ回路基板６の裏側を支える支持部材１７ａと、インバータ回路基板６の表側を支える支持部材１７ｂから形成され、支持部材１７ａ、１７ｂの間にインバータ回路基板６を狭持する。インバータ回路基板６を確実に支持するため、狭持部１６の設けられていない係合孔１５ｂと１５ｃの間には支持台１７ｃが設けられ、支持台１７ｃはインバータ回路基板６を液晶パネルの裏面１に平行に支持するため、支持部材１７ａと等しい高さに設計されている。支持部材１７ａと１７ｂとの隙間はインバータ回路基板６の上下方向への移動を防止するため、インバータ回路基板６の厚さとほぼ等しく設計されている。
【００２６】
また、狭持部１６に存在する支持部材１７ａの中央部には係止部１８が設けられ、後述する保護部材の装着によってインバータ回路基板６の端部が係止部１８に当接することによりインバータ回路基板６が圧着固定される。狭持部１６の底面部１４からの立ち上がり部には、後述する保護部材の係止爪が係合する係合溝１９が設けられている。係合孔１５ａ〜１５ｄのインバータ回路基板６が挿入される方向の開口縁には突起２０が設けられ、各係合孔１５ａ〜１５ｄに押さえ片３ａ〜３ｄが係合したときの固定用部材１３の位置を規定する。なお、固定用部材１３の中央付近には狭持部１６が設けられておらず、左右の狭持部１６の幅が異なるのは、インバータ回路基板６上の入力コネクタ９及び調光用コネクタ１０へのケーブル差込スペースを確保するためである。
【００２７】
また、図４、図５に示すように、支持部材１７ａ及び支持台１７ｃは支持部材１７ｂに比べインバータ回路基板６が挿入される方向に長く形成されており、後述するようにインバータ回路基板６の固定用部材１３への挿入が容易となる。さらに係止部１８は支持部材１７ｂの端部より内側に支持部材１７ｂと同等以上の高さまで設けられており、インバータ回路基板６を確実に固定する。
【００２８】
図６は固定用部材を表示手段の裏面１に装着した状態を示す斜視図である。固定用部材１３の４箇所に設けられた係合孔１５ａ〜１５ｄは、それぞれ液晶表示パネルの裏面１に設けられた４箇所の押さえ片３ａ〜３ｄに係合する。係合孔１５ａ〜１５ｄの大きさは、固定用部材１３の長手方向においては押さえ片３ａ〜３ｄと同等に、長手方向に対し垂直方向、すなわちインバータ回路基板６が挿入される方向においては押さえ片３ａ〜３ｄに比べ大きく形成されている。これにより、固定用部材１３はインバータ回路基板６の挿入方向に摺動可能となっている。また、３箇所のビス穴２には支持部材１７ａ、支持台１７ｃと同等の高さのスペーサ２１が付設されており、第２の状態において固定用部材１３と共にインバータ回路基板６を液晶表示パネルの裏面１に平行に固定する。２２はインバータ回路基板６の低圧側の出力コネクタ１２に接続される接続ケーブルである。
【００２９】
次に第２の状態によりインバータ回路基板を取り付ける方法について説明する。図７は第２の状態によりインバータ回路基板を取り付けた状態を示す平面図であり、図８は第２の状態によりインバータ回路基板を取り付けた状態を示す正面図であり、図９は第２の状態によりインバータ回路基板を取り付けた状態を示す側面図であり、図１０は第２の状態によりインバータ回路基板を取り付けた状態を示す断面図（図７のＡ−Ａ断面図）である。図７において、インバータ回路基板６は長手方向のコネクタ側の一辺（図面下側）を固定用部材１３の支持部材１７ａ及び１７ｂからなる狭持部１６に狭持され、トランス７側の一辺（図面上側）をビス２３によりスペーサ２１（図示せず）に固定されている。
【００３０】
図８、図９に示すように、固定用部材１３及びスペーサ２１は等しい高さｄに設計されており、インバータ回路基板６は所定の間隔ｄを隔てて液晶表示パネルの裏面１上に平行に設置される。また、図１０に示すように、固定用部材１３の支持部材１７ａと１７ｂとの隙間はインバータ回路基板６の厚さと同等に設計されており、インバータ回路基板６の端部は、支持部材１７ａ及び１７ｂの隙間に狭持され、端縁が係止部１８に当接している。
【００３１】
インバータ回路基板６の狭持部１６への装着について、図１１により詳細に説明する。図４に示した状態より、インバータ回路基板６をスペーサ２１及び固定用部材１３の上に載せる。次にインバータ回路基板６の３箇所のビス穴１１にビス２３を挿入し、スペーサ２１に螺合する。このとき図１１（ａ）に示すように、固定用部材１３は係合孔１５ａ〜１５ｄの突起２０が押さえ片３ａ〜３ｄの屈折部内面に当接する位置、すなわちインバータ回路基板６から最も離れた位置に摺動させておく。支持部材１７ａは支持部材１７ｂに比べインバータ回路基板６が挿入される方向に長く設けられているため、インバータ回路基板６の端部は支持部材１７ｂの先端には届かず、支持部材１７ａの先端には届く位置となる。
【００３２】
さらに、図１１（ｂ）に示すように、後述する保護部材をインバータ回路基板６上に装着することなどにより、固定用部材１３がインバータ回路基板６側に押され、インバータ回路基板６の端部が支持部材１７ａ及び１７ｂの隙間に挿入される。これにより、インバータ回路基板６の片側をビス止めした後においても固定用部材１３の狭持部１６に容易に挿入が可能となり、組み立て時の作業効率が向上する。さらにインバータ回路基板６の端部が係止部１８に圧着されてインバータ回路基板６の固定が確実なものとなる。このとき固定用部材１３の係合孔１５ａ〜１５ｄから突出する突起２０の上端が押さえ片３ａ〜３ｄの下面に当接するため、固定用部材１３の上方向への移動も合わせて制限される。
【００３３】
図１２は本実施形態において用いられる保護部材を示す斜視図であり、図１３は保護部材の平面図である。２４はインバータ回路基板６上に装着される保護部材であり、側面２５において固定用部材１３と当接する。保護部材２４の上面及び側面にはインバータ回路基板６より発生する熱を逃がす空気穴２６が設けられている。側面２５の下部２箇所においては係止爪２７が内側に向かって突出し、保護部材２４がインバータ回路基板６上に装着される際、固定用部材１３の係合溝１９に係合する。また、側面２５及び左右両側の側面の下端には幅広部２８が設けられ、保護部材２４を液晶表示パネルの裏面１に安定に装着する。左右両側の側面に設けられた幅広部２８の側面２５と反対側の端部にはビス穴２９が設けられ、保護部材２４を液晶表示パネルの裏面１にビス固定する。さらに、側面２５の上部中央には入力コネクタ９及び調光用コネクタ１０に接続される配線ケーブルが通過するための窓部３０が設けられている。窓部３０の位置及び大きさはインバータ回路基板６上のコネクタ９、１０の配置により任意に設定可能である。また、蓋部３１は、インバータ回路基板６のメンテナンスや交換を容易とするため開閉可能に構成されている。
【００３４】
インバータ回路基板上に保護部材を装着した状態を図１４〜図１７に示す。図１４は本実施形態の保護部材を装着した状態を示す平面図であり、図１５は保護部材を装着した状態を示す正面図であり、図１６は保護部材を装着した状態を示す側面図であり、図１７は保護部材を装着した状態を示す断面図（図１４におけるＡ−Ａ断面）である。図１４において、保護部材２４は係止爪２７が固定用部材１３の係合溝１９に嵌合し、ビス穴２９にビス３２を螺入して液晶表示パネルの裏面１にビス固定することにより液晶表示パネルの裏面１に固定される。蓋部３１は通常ビス止め等の方法により閉じられており、インバータ回路基板６のメンテナンスや交換の際に開閉される。図１５に示すように窓部３０の位置には入力コネクタ９及び調光用コネクタ１０が配置され、蓋部３１を閉じた状態でケーブルの接続が可能となっている。
【００３５】
また、図１７に示すように、保護部材２４が装着されると、固定用部材１３の狭持部１６は保護部材２４の側面２５の内面によりインバータ回路基板６側に押されるため、インバータ回路基板６の端部は支持部材１７ａ、１７ｂにより狭持され、且つ係止部１８に圧着される。インバータ回路基板６の反対側の端部はビス２３によりスペーサ２１にビス止めされているため、インバータ回路基板６は固定用部材１３及びスペーサ２１を介して液晶表示パネルの裏面１に確実に固定されることとなる。なお、保護部材２４の材質は特に制限はないが、外部に筐体を設けない平面表示装置の場合、十分な強度をもつ材質とする必要があり、またインバータ回路基板６の熱による変形、変質等を考慮すれば、金属製とするのが好ましい。保護部材２４の形状についても、本発明の趣旨を逸脱しない範囲であれば任意の形状とすることができる。
【００３６】
次に第２の状態においてインバータ回路基板６と液晶表示パネルの裏面１との間隔と温度変化との関係について説明する。表１はインバータ回路基板と液晶表示パネルの裏面との間隔を変化させた場合におけるインバータ回路基板及び基板周辺の温度上昇測定結果を示したものである。測定は入力電圧を１４Ｖとし、平面表示装置は壁に立てかけた状態で２時間測定を行い、インバータ回路基板６と裏面１との間隔が２ｍｍの場合、すなわち固定用部材１３を使用しない第１の状態を基準として温度低減効果を調べた。なお、表中の温度上昇値は３〜６箇所の測定値を平均したものである。
【００３７】
【表１】

表に示したように、裏面１とインバータ回路基板６との間隔が５ｍｍの場合は、インバータ回路基板及び基板周辺の各部位における温度低下は第１の状態（２ｍｍ）と比べて０〜１．５℃程度であった。これに対し裏面１とインバータ回路基板６との間隔が７．５ｍｍの場合は、第１の状態と比べて３〜６℃の温度低下が見られ、更に間隔を１０ｍｍとした場合は、第１の状態と比べて４〜８℃の温度低下が見られた。
【００３８】
この結果より、裏面１とインバータ回路基板６との間隔を広げて設置した場合には、インバータ回路基板の周辺のみでなくインバータ回路基板自体の温度上昇も低減されることが確認された。これは、インバータ回路基板が周囲の空気により空冷されるためであると考えられる。また、温度低減効果を生じるためにはインバータ回路基板６を裏面１から５ｍｍ以上離して設置することが必要であると考えられるが、裏面からの距離が離れるほど温度低減には有利となる反面、平面表示装置の薄型化の観点からは好ましくない。したがって、液晶表示パネルの裏面とインバータ回路基板との間隔は５〜１５ｍｍ程度とするのが好ましい。
【００３９】
本実施形態においては、支持部材１７ａ及び支持台１７ｃは１７ｂに比べインバータ回路基板６が挿入される方向に長く形成されているが、支持部材１７ａ及び支持台１７ｃは１７ｂと同等の長さであっても良く、逆に支持部材１７ｂを支持部材１７ａ及び支持台１７ｃより長く形成しても良い。支持部材１７ｂを１７ａ及び支持台１７ｃより長く形成した場合は、係合孔１５ａ〜１５ｄを押さえ片３ａ〜３ｄに係合し、インバータ回路基板６の端部を支持部材１７ａと底面部１４の間に入れた状態で固定用部材１３をインバータ回路基板６から離れた位置に摺動した後、下から上にインバータ回路基板６を持ち上げ、さらに固定用部材１３をインバータ回路基板６に近い位置に摺動させて狭持部１６に狭持させることとなる。
【００４０】
また、固定用部材１３は液晶表示パネルの裏面１に沿って摺動可能な構成としたが、例えば固定用部材１３を裏面１に固定する構成としても良い。この場合はインバータ回路基板６の端部を狭持部１６に狭持した後に他端をスペーサ２１にビス止めする。また、固定用部材１３の形状は本実施形態に限定されるものではなく、本発明の趣旨を逸脱しない範囲で種々の形状のものを使用することができる。
【００４１】
本実施形態においては、表示手段として液晶表示パネルを用いた場合についてのみ説明したが、本発明は他の平面表示装置、例えば有機エレクトロルミネッセンスを用いた自発光型の表示装置にも適用できるのはもちろんである。また、回路基板としてはインバータ回路基板の固定についてのみ説明したが、表示手段の駆動に用いられる他の制御基板の固定にも適用でき、特に温度上昇に弱い制御基板の固定手段として有効である。
【００４２】
【発明の効果】
本発明によると、平面状の表示手段と、前記表示手段の駆動に用いられる回路基板と、前記回路基板を保護する保護部材と、を備えた平面表示装置において、前記回路基板を前記表示手段の裏面に設けられた押さえ片を用いて前記裏面に直接取り付ける第１の状態と、前記表示手段の裏面に着脱可能な固定用部材を介して取り付ける第２の状態とが選択自在であり、前記第２の状態では前記第１の状態に比べて前記回路基板と前記表示手段の裏面との間隔が広いこととしたため、平面表示装置を筐体に組み込んで使用する場合には回路基板を表示手段の裏面に直接取り付ける第１の状態を選択し、筐体に組み込まずに使用する場合には表示手段の裏面の温度が上昇しないように、回路基板を表示手段の裏面に固定用部材を介して間隔を広げて取り付ける第２の状態を適宜選択することができる。
【００４３】
また、第２の状態においては、回路基板の対向する二辺のうち一方は表示手段の裏面に立設されたスペーサにビス固定され、他方は狭持部を有する細長状の固定用部材により狭持されることとしたので、第２の状態において簡易な構造の固定用部材を用いて回路基板と表示手段の裏面との間隔を広くすることができる。
【００４４】
また、固定用部材の狭持部は回路基板を表裏両側から支持する支持部材から構成され、回路基板の裏側を支持する支持部材は表側を支持する支持部材よりも回路基板の挿入方向に長く形成されていることとしたので、回路基板を固定用部材の上方向から容易に狭持させることができる。
【００４５】
また、固定用部材は、保護部材の装着前は表示手段の裏面に沿って回路基板の挿入方向に摺動可能に保持されており、保護部材の装着により、保護部材の側面内側が固定用部材に当接して表示手段の裏面に固定されることとしたので、回路基板の他端を固定した状態においても狭持部への回路基板の挿入が一層容易となり、また、別途固定用部材の固定手段を必要とせずパーツ数も減少し、組み立て効率も向上するためコスト面でも有利となる。
【００４６】
また、第２の状態においては、回路基板と表示手段の裏面との間隔が５ｍｍ以上であることとしたので、回路基板及び基板周辺の温度上昇をより確実に防止する有用な平面表示装置を提供することができる。
【００４７】
また、表示手段が、液晶表示素子と、前記液晶表示素子を照明する照明手段とを備えた液晶表示パネルであることとしたので、ＬＣＤを用いた平面表示装置において、表示手段を筐体に組み込まずに使用する場合に更なる薄型化、軽量化を実現することができる。また、回路基板を照明手段に電流を供給するインバータ回路基板としたので、筐体やリアフレームを用いない場合でもインバータ回路基板及び周辺部が高温となるのを防ぎ、強度面、安全面で優れたＬＣＤを用いた平面表示装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の第１実施形態に用いられる表示手段の裏面図である。
【図２】本実施形態の第１の状態によりインバータ回路基板を取り付ける様子を示した斜視図である。
【図３】本実施形態の第２の状態において用いられる固定用部材を示す斜視図である。
【図４】本実施形態の固定用部材を示す平面図である。
【図５】本実施形態の固定用部材を示す側面図である。
【図６】本実施形態の固定用部材を表示手段の裏面に装着した状態を示す斜視図である。
【図７】本実施形態の第２の状態によりインバータ回路基板を取り付けた状態を示す平面図である。
【図８】第２の状態によりインバータ回路基板を取り付けた状態を示す正面図である。
【図９】第２の状態によりインバータ回路基板を取り付けた状態を示す側面図である。
【図１０】第２の状態によりインバータ回路基板を取り付けた状態を示す断面図である。
【図１１】第２の状態におけるインバータ回路基板の狭持部への装着状態を示す断面図である。
【図１２】本実施形態において用いられる保護部材を示す斜視図である。
【図１３】本実施形態において用いられる保護部材を示す平面図である。
【図１４】第２の状態において保護部材をインバータ回路基板上に装着した状態を示す平面図である。
【図１５】第２の状態において保護部材をインバータ回路基板上に装着した状態を示す正面図である。
【図１６】第２の状態において保護部材をインバータ回路基板上に装着した状態を示す側面図である。
【図１７】第２の状態において保護部材をインバータ回路基板上に装着した状態を示す断面図である。
【符号の説明】
１．裏面
２．ビス穴
３ａ〜３ｄ．押さえ片
４．突部
６．インバータ回路基板
１３．固定用部材
１５ａ〜１５ｄ．係合孔
１６．狭持部
１７ａ、１７ｂ．支持部材
１７ｃ．支持台
１８．係止部
２１．スペーサ
２４．保護部材
２７．係止爪
３０．窓部
３１．蓋部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flat display device using a liquid crystal display device or the like.
[0002]
[Prior art]
2. Description of the Related Art A flat display device using an LCD is widely used for a large-sized television or the like, and a large display device of 40 inches has been developed. 2. Description of the Related Art A flat display device using an LCD includes a liquid crystal display panel including a liquid crystal display element in which liquid crystal is sealed between a pair of opposing electrode substrates and a backlight device for illuminating the liquid crystal display element from the back, and a liquid crystal display panel for driving the liquid crystal display panel. It is composed of various circuit boards used. Since these flat display devices are usually used by being incorporated in a housing such as a television or a monitor, there is no fear that a user directly touches around various circuit boards disposed on the back surface of the liquid crystal display panel. Was directly fixed to the back surface of the liquid crystal display panel, and the surface was protected by a cover made of polyethylene terephthalate (PET).
[0003]
In recent years, the demand for thinner and lighter flat display devices has become stronger, and flat display devices that use a system board or the like attached to the back surface of a liquid crystal display panel without being incorporated in a housing have been proposed. In this case, since the liquid crystal display panel is not incorporated in the housing, the strength of the conventional PET protective cover is insufficient, and the user may touch the rear substrate or the like. The circuit board is dangerous because it becomes hot during use.
[0004]
Therefore, it is conceivable to protect the inverter circuit board with a metal cover. In a flat display device having a rear frame on the back surface, a method is disclosed in which an inverter circuit board is directly fixed to the inside of the rear frame to reduce the thickness, weight, and cost of the flat display device. Reference 1).
[0005]
[Patent Document 1]
JP 2001-337621 A
[0006]
[Problems to be solved by the invention]
However, in the method described in Patent Literature 1, since the inverter circuit board is directly fixed to the rear frame of the flat panel display, the temperature of the rear frame becomes high due to the heat generated by the inverter circuit board during use, which is dangerous. Further, in order to achieve further reduction in thickness and weight, it may be possible to adopt a configuration in which no rear frame is used, but in this case, it becomes difficult to fix the inverter circuit board.
[0007]
In view of the above problems, the present invention provides a flat display device in which an inverter circuit board is appropriately protected even in a flat display device in which a liquid crystal display panel is used without being incorporated in a housing, and there is no concern about temperature rise of the display device itself. It is intended to provide a device.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a flat display device comprising: a flat display unit; a circuit board used for driving the display unit; and a protection member for protecting the circuit board. A first state in which the substrate is directly attached to the back surface by using a holding piece provided on the back surface of the display means, and a second state in which the substrate is attached to the back surface of the display means via a detachable fixing member can be freely selected. In the second state, the distance between the circuit board and the back surface of the display means is wider than in the first state.
[0009]
According to this configuration, when the flat panel display device is used by being incorporated in a housing, the user does not have to touch the periphery of the circuit board. Therefore, the first state in which the circuit board is directly mounted on the back surface of the display means is selected. The second state in which the circuit board is mounted on the back surface of the display means with a wider space between the back face of the display means and the fixing means so that the temperature around the circuit board does not rise when used without being incorporated in the body. Can be selected. Further, by making the fixing member detachable, the method of attaching the circuit board can be appropriately selected at the time of assembling according to the application only by attaching the fixing member.
[0010]
Further, according to the present invention, in the flat display device having the above configuration, in the second state, one of two opposing sides of the circuit board is fixed to a spacer provided upright on a back surface of the display means, and the other is fixed. Is held by an elongated fixing member having a holding portion.
[0011]
According to this configuration, in the second state, the distance between the circuit board and the back surface of the display means can be increased by using a fixing member having a simple structure.
[0012]
Further, according to the present invention, in the flat display device having the above-described configuration, the holding portion includes a support member that supports the circuit board from both the front and back sides, and the support member that supports the back side of the circuit board supports the front side. It is formed to be longer in the insertion direction of the circuit board than the support member.
[0013]
According to this configuration, it is possible to easily and reliably hold the circuit board, and the support member that supports the back side of the circuit board among the support members that form the holding portion is more than the support member that supports the front side. Since the circuit board is formed long in the insertion direction of the circuit board, the circuit board can be easily held from above the fixing member.
[0014]
Further, in the flat display device having the above configuration, the fixing member is slidably held in a direction in which the circuit board is inserted along a back surface of the display unit before the protection member is attached, By mounting the protection member, the inner side surface of the protection member comes into contact with the fixing member and is fixed to the back surface of the display means.
[0015]
According to this configuration, even when the other end of the circuit board is fixed, the insertion of the circuit board into the holding portion is further facilitated, and the efficiency in the assembling process is improved. Further, since the fixing member is fixed to the back surface of the display means by attaching a protection member for protecting the circuit board, no separate fixing means is required for the fixing member, and the number of parts is reduced, which is advantageous in cost. .
[0016]
Further, according to the present invention, in the flat display device having the above configuration, in the second state, the distance between the circuit board and the back surface of the display unit is 5 mm or more. As a result, it is possible to effectively prevent a rise in the temperature of the circuit board and the periphery of the board.
[0017]
Further, according to the present invention, in the flat display device having the above configuration, the display means is a liquid crystal display panel including a liquid crystal display element and an illuminating means for illuminating the liquid crystal display element. Accordingly, in a flat display device using an LCD, when used without being incorporated in a housing, a further reduction in thickness and weight can be realized, and a flat display device excellent in safety can be provided.
[0018]
Further, according to the present invention, the circuit board is an inverter circuit board that supplies a current to the lighting unit. Thus, even when the housing and the rear frame are not used, the temperature around the inverter circuit board can be prevented from becoming high, and a flat display device using an LCD excellent in strength and safety can be provided.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a rear view of the display means of the present invention, and FIG. 2 is a perspective view showing a state in which a circuit board is mounted in a first state. Here, a case will be described in which a liquid crystal display panel including a liquid crystal display element and an illuminating means for illuminating the liquid crystal display element from the back is used as a display means, and an inverter circuit board is used as a circuit board.
[0020]
In FIG. 1, screw holes 2 for screwing a circuit board are provided in three places on the back surface 1 of the liquid crystal display panel, and the periphery of the screw holes 2 is formed so as to slightly project from the back surface 1. 3a to 3d are holding pieces for holding the inverter circuit board in the first state. The holding pieces 3a to 3d are provided at four places in a row in parallel with the row of the screw holes 2, and are formed so that the respective tips face the direction of the screw holes 2.
[0021]
Reference numeral 4 denotes a protrusion for adjusting the height of the control board, and is provided at two places between the holding

pieces

3a and 3b and between the holding pieces 3c and 3d at the same height as the screw hole 2. The distance between the lower surfaces of the holding pieces 3a to 3d and the upper surface of the protrusion 4 is designed to be substantially equal to the thickness of the inverter circuit board. Reference numeral 5 denotes a lamp connector for connecting a backlight lamp (not shown), which is illumination means of the liquid crystal display panel, to an inverter circuit, and is connected to an output connector of the inverter circuit described later.
[0022]
In FIG. 2, reference numeral 6 denotes an inverter circuit board, and eight transformers 7 for converting an AC voltage to a DC voltage are provided on the upper surface. Reference numeral 8 denotes a high-voltage output connector for connecting the backlight and the inverter circuit, and is connected to the lamp connector 5. At an end of the inverter circuit board 6 opposite to the transformer 7 and the output connector 8, two input connectors 9 to which a power cable is connected are provided, and a dimming connector 10 for adjusting the brightness of the illumination means is provided as an input connector. 9 is provided at one place. Further, three screw holes 11 are provided at the end of the output connector 8 side at positions corresponding to the screw holes 2 on the back surface 1 of the liquid crystal panel.
[0023]
Reference numeral 12 denotes a low-voltage output connector, which is connected to a backlight lamp (not shown) by a connection cable. Although other components and circuits such as a choke coil also exist on the inverter circuit board 6, their description is omitted here for convenience of explanation. In the first state, one side of the inverter circuit board 6 on the side of the input connector 9 and the dimming connector 10 is sandwiched between the holding pieces 3a to 3d and the protruding portion 4, and an end of one side of the opposite side. A screw (not shown) is passed through a screw hole 11 provided on the rear surface 1 and screwed into a screw hole 2 provided on the rear surface 1 to be fixed to the rear surface 1 of the display means. At this time, the inverter circuit board 6 does not come into close contact with the back surface 1 by the screw holes 2 and the projections 4 and holds a predetermined gap.
[0024]
Next, a method of attaching the inverter circuit board in the second state will be described. 3 is a perspective view of the fixing member used in the second state, FIG. 4 is a plan view of the fixing member, and FIG. 5 is a side view of the fixing member. In FIG. 3, the fixing member 13 is formed to have substantially the same length as the longitudinal direction of the inverter circuit board 6, and rectangular engaging holes 15a to 15d are engaged with the holding pieces 3a to 3d at four places on the bottom surface portion 14. It is provided in the position where it matches. Between the

engagement holes

15a and 15b and between 15c and 15d, a holding portion 16 for holding the inverter circuit board 6 is provided upright from the bottom portion 14.
[0025]
The holding portion 16 is formed of a support member 17a that supports the back side of the inverter circuit board 6 and a support member 17b that supports the front side of the inverter circuit board 6, and holds the inverter circuit board 6 between the

support members

17a and 17b. In order to securely support the inverter circuit board 6, a support 17c is provided between the engagement holes 15b and 15c where the holding portion 16 is not provided, and the support 17c connects the inverter circuit board 6 to the rear surface of the liquid crystal panel. In order to support it in parallel to 1, it is designed at the same height as the support member 17a. The gap between the supporting

members

17a and 17b is designed to be substantially equal to the thickness of the inverter circuit board 6 in order to prevent the inverter circuit board 6 from moving in the vertical direction.
[0026]
A locking portion 18 is provided at the center of the support member 17a existing in the holding portion 16, and the end of the inverter circuit board 6 is brought into contact with the locking portion 18 by attaching a protection member described later, so that the inverter is not driven. The circuit board 6 is fixed by crimping. An engagement groove 19 is provided at a rising portion of the holding portion 16 from the bottom surface portion 14 to be engaged with a locking claw of a protection member described later. A projection 20 is provided at an opening edge of the engagement holes 15a to 15d in a direction in which the inverter circuit board 6 is inserted, and the fixing member 13 when the holding pieces 3a to 3d are engaged with the engagement holes 15a to 15d. Specify the position of. Note that the holding portion 16 is not provided near the center of the fixing member 13, and the widths of the left and right holding portions 16 are different because the input connector 9 and the dimming connector 10 on the inverter circuit board 6 are different. This is to secure a space for cable insertion into the cable.
[0027]
As shown in FIGS. 4 and 5, the support member 17a and the support base 17c are formed longer in the direction in which the inverter circuit board 6 is inserted than the support member 17b. Insertion into the fixing member 13 becomes easy. Further, the locking portion 18 is provided inside the end of the support member 17b to a height equal to or higher than that of the support member 17b, and securely fixes the inverter circuit board 6.
[0028]
FIG. 6 is a perspective view showing a state where the fixing member is mounted on the back surface 1 of the display means. The engagement holes 15a to 15d provided at four places of the fixing member 13 engage with four holding pieces 3a to 3d provided at the back surface 1 of the liquid crystal display panel, respectively. The size of the engaging holes 15a to 15d is the same as that of the pressing pieces 3a to 3d in the longitudinal direction of the fixing member 13, and is perpendicular to the longitudinal direction, that is, the pressing piece in the direction in which the inverter circuit board 6 is inserted. It is formed larger than 3a to 3d. Thereby, the fixing member 13 is slidable in the insertion direction of the inverter circuit board 6. The three screw holes 2 are provided with spacers 21 having the same height as the support member 17a and the support base 17c. In the second state, together with the fixing member 13, the inverter circuit board 6 is connected to the liquid crystal display panel. It is fixed parallel to the back surface 1. A connection cable 22 is connected to the low-voltage output connector 12 of the inverter circuit board 6.
[0029]
Next, a method of attaching the inverter circuit board in the second state will be described. FIG. 7 is a plan view showing a state where the inverter circuit board is mounted in the second state, FIG. 8 is a front view showing a state where the inverter circuit board is mounted in the second state, and FIG. FIG. 10 is a side view showing a state where the inverter circuit board is attached according to the state, and FIG. 10 is a cross-sectional view (sectional view taken along the line AA of FIG. 7) showing a state where the inverter circuit board is attached according to the second state. In FIG. 7, the inverter circuit board 6 has one side (lower side in the drawing) of the connector side in the longitudinal direction held by the holding section 16 composed of the supporting

members

17a and 17b of the fixing member 13, and one side of the transformer 7 (in the drawing). The upper side) is fixed to a spacer 21 (not shown) by a screw 23.
[0030]
As shown in FIGS. 8 and 9, the fixing member 13 and the spacer 21 are designed to have the same height d, and the inverter circuit board 6 is arranged on the back surface 1 of the liquid crystal display panel in parallel with a predetermined distance d. Will be installed. As shown in FIG. 10, the gap between the

support members

17a and 17b of the fixing member 13 is designed to be equal to the thickness of the inverter circuit board 6, and the end of the inverter circuit board 6 is connected to the

support members

17a and 17a. The end is in contact with the locking portion 18 while being held between the gaps 17b.
[0031]
The attachment of the inverter circuit board 6 to the holding portion 16 will be described in detail with reference to FIG. The inverter circuit board 6 is placed on the spacer 21 and the fixing member 13 from the state shown in FIG. Next, screws 23 are inserted into the three screw holes 11 of the inverter circuit board 6 and screwed to the spacer 21. At this time, as shown in FIG. 11A, the fixing member 13 is located farthest from the inverter circuit board 6 at the position where the projections 20 of the engagement holes 15a to 15d abut on the inner surfaces of the bending portions of the holding pieces 3a to 3d. Slide to position. Since the support member 17a is provided to be longer in the direction in which the inverter circuit board 6 is inserted than the support member 17b, the end of the inverter circuit board 6 does not reach the tip of the support member 17b, and is located at the tip of the support member 17a. Is a reachable location.
[0032]
Further, as shown in FIG. 11B, the fixing member 13 is pushed toward the inverter circuit board 6 by mounting a protective member described later on the inverter circuit board 6 and the like. Is inserted into the gap between the

support members

17a and 17b. As a result, even after one side of the inverter circuit board 6 is screwed, it can be easily inserted into the holding portion 16 of the fixing member 13, and the work efficiency at the time of assembly is improved. Further, the end of the inverter circuit board 6 is crimped to the locking portion 18 so that the inverter circuit board 6 is securely fixed. At this time, since the upper ends of the projections 20 protruding from the engagement holes 15a to 15d of the fixing member 13 abut against the lower surfaces of the holding pieces 3a to 3d, the upward movement of the fixing member 13 is also restricted.
[0033]
FIG. 12 is a perspective view showing a protection member used in the present embodiment, and FIG. 13 is a plan view of the protection member. Reference numeral 24 denotes a protection member mounted on the inverter circuit board 6, and abuts against the fixing member 13 on the side surface 25. Air holes 26 for releasing heat generated from the inverter circuit board 6 are provided on the upper and side surfaces of the protection member 24. At two lower portions of the side surface 25, the locking claws 27 protrude inward, and when the protection member 24 is mounted on the inverter circuit board 6, it engages with the engagement groove 19 of the fixing member 13. A wide portion 28 is provided at the lower end of the side surface 25 and the left and right side surfaces, and the protection member 24 is stably mounted on the back surface 1 of the liquid crystal display panel. Screw holes 29 are provided at the end opposite to the side surface 25 of the wide portion 28 provided on the left and right side surfaces, and the protective member 24 is fixed to the back surface 1 of the liquid crystal display panel with screws. Further, a window 30 through which a wiring cable connected to the input connector 9 and the dimming connector 10 passes is provided at the upper center of the side surface 25. The position and size of the window 30 can be set arbitrarily by the arrangement of the

connectors

9 and 10 on the inverter circuit board 6. The lid 31 is configured to be openable and closable to facilitate maintenance and replacement of the inverter circuit board 6.
[0034]
FIGS. 14 to 17 show a state in which the protective member is mounted on the inverter circuit board. FIG. 14 is a plan view showing a state where the protection member of the present embodiment is mounted, FIG. 15 is a front view showing a state where the protection member is mounted, and FIG. 16 is a side view showing a state where the protection member is mounted. FIG. 17 is a cross-sectional view (cross-section AA in FIG. 14) showing a state where the protection member is mounted. In FIG. 14, the protection member 24 is formed by engaging the locking claw 27 in the engagement groove 19 of the fixing member 13, screwing the screw 32 into the screw hole 29, and fixing the screw to the rear surface 1 of the liquid crystal display panel. It is fixed to the back surface 1 of the liquid crystal display panel. The lid 31 is normally closed by a method such as screwing, and is opened and closed when the inverter circuit board 6 is maintained or replaced. As shown in FIG. 15, the input connector 9 and the dimming connector 10 are arranged at the position of the window 30, and a cable can be connected with the lid 31 closed.
[0035]
As shown in FIG. 17, when the protection member 24 is mounted, the holding portion 16 of the fixing member 13 is pushed toward the inverter circuit board 6 by the inner surface of the side surface 25 of the protection member 24. 6 is held by supporting

members

17a and 17b, and is pressed against the locking portion 18. Since the opposite end of the inverter circuit board 6 is screwed to the spacer 21 with the screw 23, the inverter circuit board 6 is securely fixed to the back surface 1 of the liquid crystal display panel via the fixing member 13 and the spacer 21. The Rukoto. The material of the protection member 24 is not particularly limited. However, in the case of a flat display device having no external housing, it is necessary to use a material having sufficient strength. Considering the above, it is preferable to use metal. The shape of the protection member 24 can be any shape as long as it does not depart from the gist of the present invention.
[0036]
Next, the relationship between the distance between the inverter circuit board 6 and the back surface 1 of the liquid crystal display panel and the temperature change in the second state will be described. Table 1 shows the measurement results of the temperature rise around the inverter circuit board and the substrate when the distance between the inverter circuit board and the rear surface of the liquid crystal display panel is changed. The measurement was performed with the input voltage set to 14 V and the flat panel display was measured for 2 hours while standing against the wall. When the distance between the inverter circuit board 6 and the back surface 1 was 2 mm, that is, the first without using the fixing member 13 was used. The temperature reduction effect was examined based on the state. In addition, the temperature rise value in a table | surface is an average of the measured value of 3-6 places.
[0037]
[Table 1]

As shown in the table, when the distance between the back surface 1 and the inverter circuit board 6 is 5 mm, the temperature drop in each part around the inverter circuit board and the board is 0 to 1 .0 in comparison with the first state (2 mm). It was about 5 ° C. On the other hand, when the distance between the back surface 1 and the inverter circuit board 6 is 7.5 mm, a temperature drop of 3 to 6 ° C. is observed as compared with the first state. A temperature decrease of 4 to 8 ° C. was observed as compared with the state of No.
[0038]
From this result, it was confirmed that when the space between the back surface 1 and the inverter circuit board 6 was increased, the temperature rise not only in the periphery of the inverter circuit board but also in the inverter circuit board itself was reduced. This is probably because the inverter circuit board is air-cooled by ambient air. It is considered that it is necessary to install the inverter circuit board 6 at a distance of 5 mm or more from the back surface 1 in order to produce a temperature reduction effect. It is not preferable from the viewpoint of reducing the thickness of the flat display device. Therefore, it is preferable that the distance between the back surface of the liquid crystal display panel and the inverter circuit board is about 5 to 15 mm.
[0039]
In the present embodiment, the support member 17a and the support base 17c are formed longer in the direction in which the inverter circuit board 6 is inserted than the support member 17b, but the support member 17a and the support base 17c have the same length as 17b. Alternatively, the support member 17b may be formed longer than the support member 17a and the support base 17c. When the support member 17b is formed longer than the support member 17a and the support base 17c, the engagement holes 15a to 15d are engaged with the holding pieces 3a to 3d, and the end of the inverter circuit board 6 is moved between the support member 17a and the bottom portion 14. After the fixing member 13 is slid to a position away from the inverter circuit board 6 in the state of being inserted, the inverter circuit board 6 is lifted up from below, and the fixing member 13 is further slid to a position close to the inverter circuit board 6. It is moved to be held by the holding section 16.
[0040]
Further, the fixing member 13 is configured to be slidable along the rear surface 1 of the liquid crystal display panel. However, for example, the fixing member 13 may be configured to be fixed to the rear surface 1. In this case, the end of the inverter circuit board 6 is held by the holding section 16 and the other end is screwed to the spacer 21. Further, the shape of the fixing member 13 is not limited to the present embodiment, and various shapes can be used without departing from the gist of the present invention.
[0041]
In the present embodiment, only the case where a liquid crystal display panel is used as the display means has been described. However, the present invention can be applied to other flat display devices, for example, self-luminous display devices using organic electroluminescence. Of course. Although only the fixing of the inverter circuit board has been described as the circuit board, the present invention can be applied to the fixing of another control board used for driving the display means, and is particularly effective as a means for fixing the control board which is susceptible to temperature rise.
[0042]
【The invention's effect】
According to the present invention, in a flat display device including a flat display means, a circuit board used for driving the display means, and a protection member for protecting the circuit board, the circuit board includes A first state of directly attaching to the back surface using a holding piece provided on the back surface and a second state of attaching to the back surface of the display means via a detachable fixing member are freely selectable. In the state 2, the distance between the circuit board and the back surface of the display means is larger than that in the first state. Therefore, when the flat display device is used by being incorporated in a housing, the circuit board is used as the display means. When the first state in which the circuit board is directly attached to the back surface is selected and the device is used without being incorporated in the housing, the circuit board is spaced from the back surface of the display means via a fixing member so that the temperature of the back surface of the display means does not rise. Spread out The second state can be appropriately selected to give Ri.
[0043]
In the second state, one of the two opposing sides of the circuit board is screw-fixed to a spacer provided on the back surface of the display means, and the other is narrowed by an elongated fixing member having a holding portion. As a result, the distance between the circuit board and the back surface of the display means can be increased in the second state by using a fixing member having a simple structure.
[0044]
In addition, the holding portion of the fixing member is formed of a support member that supports the circuit board from both sides, and the support member that supports the back side of the circuit board is formed longer in the insertion direction of the circuit board than the support member that supports the front side. Therefore, the circuit board can be easily held from above the fixing member.
[0045]
In addition, the fixing member is slidably held in the insertion direction of the circuit board along the back surface of the display means before the protection member is mounted, and the inside of the side surface of the protection member is fixed by the mounting of the protection member. , So that the circuit board can be more easily inserted into the holding portion even when the other end of the circuit board is fixed, and the fixing member is separately fixed. No means is required, the number of parts is reduced, and assembling efficiency is improved, which is advantageous in terms of cost.
[0046]
Further, in the second state, since the distance between the circuit board and the back surface of the display means is set to 5 mm or more, a useful flat display device that more reliably prevents a rise in temperature around the circuit board and the board is provided. can do.
[0047]
Further, since the display means is a liquid crystal display panel including a liquid crystal display element and an illuminating means for illuminating the liquid crystal display element, the display means is incorporated in a housing in a flat display device using an LCD. In the case where it is used without using, it is possible to further reduce the thickness and weight. In addition, since the circuit board is an inverter circuit board that supplies current to the lighting means, it prevents high temperatures in the inverter circuit board and its peripheral parts even when no housing or rear frame is used, and is excellent in strength and safety. A flat display device using an LCD can be provided.
[Brief description of the drawings]
FIG. 1 is a rear view of a display unit used in a first embodiment of the present invention.
FIG. 2 is a perspective view showing a state in which an inverter circuit board is mounted in a first state of the embodiment.
FIG. 3 is a perspective view showing a fixing member used in a second state of the embodiment.
FIG. 4 is a plan view showing a fixing member of the embodiment.
FIG. 5 is a side view showing a fixing member of the embodiment.
FIG. 6 is a perspective view showing a state where the fixing member of the present embodiment is mounted on the back surface of the display means.
FIG. 7 is a plan view showing a state in which an inverter circuit board is attached according to the second state of the present embodiment.
FIG. 8 is a front view showing a state in which the inverter circuit board is mounted in the second state.
FIG. 9 is a side view showing a state where the inverter circuit board is mounted in the second state.
FIG. 10 is a cross-sectional view showing a state where the inverter circuit board is mounted in the second state.
FIG. 11 is a cross-sectional view illustrating a state where the inverter circuit board is mounted on the holding portion in the second state.
FIG. 12 is a perspective view showing a protection member used in the present embodiment.
FIG. 13 is a plan view showing a protection member used in the present embodiment.
FIG. 14 is a plan view showing a state where the protection member is mounted on the inverter circuit board in the second state.
FIG. 15 is a front view showing a state where the protection member is mounted on the inverter circuit board in the second state.
FIG. 16 is a side view showing a state where the protection member is mounted on the inverter circuit board in the second state.
FIG. 17 is a cross-sectional view showing a state in which the protection member is mounted on the inverter circuit board in the second state.
[Explanation of symbols]
1. Back
2. Screw hole
3a to 3d. Holding piece
4. Protrusion
6. Inverter circuit board
13. Fixing member
15a to 15d. Engagement hole
16. Holding part
17a, 17b. Support member
17c. Support
18. Locking part
21. Spacer
24. Protective material
27. Locking claw
30. Window
31. Lid

Claims

A flat display device comprising: a flat display unit; a circuit board used for driving the display unit; and a protection member for protecting the circuit board.
A first state in which the circuit board is directly attached to the back surface using a holding piece provided on the back surface of the display means, and a second state in which the circuit board is attached to the back surface of the display means via a detachable fixing member. Wherein the distance between the circuit board and the back surface of the display means is wider in the second state than in the first state.

In the second state, one of the two opposing sides of the circuit board is screw-fixed to a spacer erected on the back surface of the display means, and the other is an elongated fixing member having a holding portion. The flat panel display according to claim 1, wherein the flat panel display is held.

The holding portion is configured by a support member that supports the circuit board from both sides, and the support member that supports the back side of the circuit board is more inserted in the circuit board insertion direction than the support member that supports the front side. The flat display device according to claim 2, wherein the flat display device is formed to be long.

The fixing member is slidably held in the insertion direction of the circuit board along the back surface of the display means before the protection member is mounted. The flat display device according to any one of claims 1 to 3, wherein a fixing member contacts the fixing member and is fixed to a back surface of the display means.

On the back surface of the display means, a plurality of pressing pieces for holding one side of the circuit board in the first state and fixing means for fixing the other opposite side are provided, and the fixing member is A plurality of engagement holes that engage with the holding pieces, an engagement groove that engages with a locking claw provided on the protection member, and a holding portion including a support member that supports the circuit board from both front and back sides. The support member that supports the back side of the circuit board is formed longer in the insertion direction of the circuit board than the support member that supports the front side, and in the first state, the support member faces the circuit board. Two sides are fixed by the pressing piece and the fixing means, and in the second state, the fixing member engages the engaging hole with the pressing piece to move along the back surface of the display means. Slide in the insertion direction of the circuit board The fixing member is slid to a position farthest from the circuit board, and one side of the circuit board is screw-fixed to a spacer provided on the fixing means. The fixing member is slid toward the circuit board side while only the back side of one side is supported by the support member to support the front and back sides of the circuit board, and the locking claw is engaged with the engagement groove. In this case, the inside of the side surface of the protection member is brought into contact with the fixing member, and the protection member is fixed to the back surface of the display unit together with the fixing member holding the circuit board. The flat panel display according to claim 1.

6. The flat display device according to claim 1, wherein in the second state, a distance between the circuit board and a back surface of the display unit is 5 mm or more. 7.

The flat display device according to any one of claims 1 to 6, wherein the display means is a liquid crystal display panel including a liquid crystal display element and illumination means for illuminating the liquid crystal display element.

The flat panel display according to claim 7, wherein the circuit board is an inverter circuit board that supplies power to the lighting unit.