JP2004039080A - Magnetic recording and reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems such as power reduction, drop-outs in the reproduction output of a magnetic recording and reproducing device which performs magnetic recording and/or reproduction due to the dust sloughing off or moving from another part (which is called a slough powder). <P>SOLUTION: The device is provided with a cleaning mechanism 2 which scrapes the sticking powder on a magnetic recording medium. The cleaning mechanism 2 consists of a cleaning roller Rc which is brought into contact with a magnetic head and is separated from the head and a scraping blade B, and the blade B is constituted so that the ridgeline of the edge of the blade is extended in the axial direction of the roller Rc and the edge can slide along the periphery of the roller by the rotation of the roller. Thus, the slough powder on the magnetic layer of the magnetic recording medium which is moved from the magnetic head and stuck to the roller is scraped off by the blade and the power is prevented from moving from the cleaning roller and sticking to the magnetic head again. <P>COPYRIGHT: (C)2004,JPO

Description

【００２９】
これによれば、仰角θを３０°〜６０°とした実施例１〜実施例３については、すべて２０巻のテープのパスで出力減衰を３ｄＢ以下にとどめることができた。
これに対し対比例１については、実施例１〜３に比し耐久性が劣る。そして、参照例１および２については、３ｄＢ以下の出力減衰にとどめることができたのは、８巻、３巻についてのパスでしか達成することができなかった。
【００３０】
一方、長時間シャトル耐久性における上述した１００回パスによるテープ巻数と、出力減衰量の測定結果を、図５に示す。図５中、曲線５１、５２、５３は、上述した実施例１、２、３による場合、曲線５４は、上述した対比例１による場合、曲線５５および５６は、上述した参照例１および２の場合である。
【００３１】
表１および図５から明らかなように、本発明装置、特に仰角θを３０°〜６０°とした実施例１〜３の仰角θによれば、出力減衰量が顕著に改善されていて、摺接粉が、磁気ヘッドから長期に渡って良好にクリーニングされていることが分かる。
【００３２】
〔第２の実施の形態〕
この実施の形態においては、図６にその一例の概略配置図を示すように、走行する磁気記録媒体Ｍに対して、摺接粉を排除するクリーニング機構１２０を具備する磁気記録再生装置とした場合である。
この例においても、ＶＴＲを例示したものであり、磁気ヘッド１が、回転磁気ヘッド装置１１として構成されているものであり、図６において、図１と対応する部分には同一符号を付して重複説明を省略する。
【００３３】
この実施の形態においては、図６に示すように、そのクリーニング機構１２０が、回転磁気ヘッド装置１１に対する磁気記録媒体Ｍの移行途上の、記録または／および再生時の順方向移行方向に関する磁気ヘッド装置１１より手前側と後方側とに、それぞれ例えばサファイヤブレードより成る爬掻ブレードＢを有する第１の爬掻ブレード部１２１と第２の爬掻ブレード部１２２とが配置された構成とされる。
【００３４】
これら第１および第２の爬掻ブレード部１２１および１２２は、図７にその背面図を示すように、それぞれブレード支持部２３に、爬掻ブレードＢが支持された構成を有する。
図８は、第１および第２の爬掻ブレード部１２１および１２２の各ブレードＢの、磁気記録媒体Ｍに対する位置関係を示す模式的平面図で、磁気記録媒体Ｍの一方の主面ｆｍ　が、磁性層を有する側の面であり、他方の主面ｆｂ　が背面側の面を示す。この図８において、磁気記録媒体Ｍは、右方向への移行を、再生および記録時の移行、すなわち順方向移行（ＦＷＤ）とし、これとは反対の左方向への巻き戻し移行を、逆方向（ＢＷＤ）とする。
【００３５】
第１および第２の爬掻ブレード部１２１および１２２の各ブレード支持部２３は、爬掻ブレードＢを、可動支持例えば回動支持する構成とする。この回動によって、各爬掻ブレードＢを、磁気記録媒体Ｍの磁性層側の面ｆｍ　と背面側ｆｂ　に対して、それぞれ実線および鎖線で示すように、摺接、離間するようになされる。
すなわち、磁気記録媒体Ｍが順方向移行ＦＷＤの状態にあるとき、支持部２３の回動によって、図８において実線図示のように、第１の爬掻ブレード部１２１の爬掻ブレードＢは、磁気記録媒体Ｍの磁性層側の面ｆｍ　に摺接するようになされ、第２の爬掻ブレード部１２２の爬掻ブレードＢは、磁気記録媒体Ｍの背面側の面ｆｂ　から離間するようになされる。
逆に、磁気記録媒体Ｍが逆方向移行ＢＷＤの状態にあるとき、支持部２３の例えば逆回転によって図８において鎖線図示のように、第１の爬掻ブレード部１２１の爬掻ブレードＢは、磁気記録媒体Ｍの磁性層側の面ｆｍ　から離間するようになされ、第２の爬掻ブレード部１２２は、磁気記録媒体Ｍの背面側の面ｆｂ　に摺接するようになされる。
【００３６】
そして、これら第１および第２の爬掻ブレード部１２１および１２２の、各爬掻ブレードＢの幅は、磁気記録媒体Ｍの全幅に渡って摺接することができるように磁気記録媒体、すなわち磁気テープの幅より大に選定される。
また、これら爬掻ブレードＢの、磁気記録媒体Ｍの各面ｆｍ　およびｆｂ　に対する仰角θは、１５°〜７５°の範囲に選定することが望ましいものである。
【００３７】
この実施形態による磁気記録再生装置によれば、磁気記録媒体に対してその磁性層側の面ｆｍ　のみならず、背面側の面ｆｂ　についても、摺接粉の爬掻すなわちスキージングがなされることによって、移動性の信号欠落、すなわちドロップアウトの原因となる欠陥部が有効に除去される。
すなわち、磁気記録媒体Ｍにおいて、何らかの原因、例えば他との摺接、あるいはリール上への磁気記録媒体Ｍの巻き込みによって、摺接粉が背面側に移着された場合においても、第２の爬掻ブレード部１２２によってこの背面側の摺接粉が排除されることによって、この摺接粉によって、磁気ヘッドが汚損されたり、磁気記録媒体が汚損されて、信号のドロップアウトの発生を有効に回避することができるものである。
【００３８】
この場合においても、クリーニング機構１２０によるクリーニング効果を示す１つの目安としては、２０００時間の連続稼働において異質破綻を来すドロップアウトの増加が認められない場合は、磁気記録再生装置として良好な装置とすることができる。
【００３９】
この本発明による実施形態における実施例、対比例と、本発明によらない参照例を挙げ、それぞれについてクリーニング効果の確認を行った。その方法は、図９にその作業のフローを示すように、クリーニングテープを一切使用することなく、１時間に相当する長さの第１巻の試験磁気テープを、１回目走行としての全長記録を行い、続いて２回目走行としてその全長に渡るドロップアウト測定（以下ＤＯ測定という）を行った。その後９７回の連続繰り返し再生を行って後、つまり、９８回目の走行を行って後、９９回目の走行において、全長に渡るＤＯ測定を行った。次に、第２巻の同様の試験磁気テープについて、同様の作業を行い、全２０巻の磁気テープに関して同様の作業を行い、実質２０００時間連続走行による試験（以下、この方法を、長時間シャトルＤＯ測定と呼称する）を行った。
【００４０】
図１０は、このＤＯ測定のシステムの構成図を示す。　　　　　　　　　　　ここで、ＶＴＲ１１１として民生用６．３５ｍｍ幅デジタルビデオレコーダであるソニー製ＤＨＲ−１０００を用い、これに第１および第２の爬掻ブレード部１２１および１２２を設け、且つこれらの爬掻ブレードＢの仰角θを変更できるようにした。
また、磁気テープは、市販品のソニー製カセットテープを用いた。そしてＶＴＲのシャトル走行には、市販のソニー製リモコンＲＭ−９５を改造し、パーソナルコンピュータ１１２と接続することで、ＶＴＲ１１１の制御を行った。また、ＶＴＲ１１１のＲＦ（高周波）再生信号波形、およびスイッチングバルス波形信号を、オシロスコープ１１３に導入し、更に市販のＤＯカウンター１１４（シバソク：ＶＨ０６ＡＺ）に取り込み再生信号のＤＯ量を測定し、記録計１１５例えばプリンターを通じて出力アウトすることで求めた。尚、ここで、ＤＯ計測サイズは、画質破綻に関する−６ｄＢ５０μｓを基準とし、最大１分当たり５個以下であることを判定基準とした。
【００４１】
〔実施例４〕〜〔実施例６〕
各実施例は、図６で示すように、第１および第２の爬掻ブレード部１２１および１２２を有するクリーニング機構２を設けた場合で、表２に示すように、第１の爬掻ブレード部１２１のブレードＢの仰角θを７５°に設定し、第２の爬掻ブレード部１２２のブレードＢの仰角θをそれぞれ１５°、４５°、７５°に設定した。
【００４２】
【表２】

【００４３】
〔対比例２〕
実施例４〜６におけると同様に、第１および第２の爬掻ブレード部１２１および１２２を設けるものの、その第２の爬掻ブレード部１２２のブレードＢの仰角θを９０°とした。
【００４４】
〔参照例３〕
この例においては、第２の爬掻ブレード部１２２の設置を省略した場合である。
〔参照例４〕
この例においては、第１の爬掻ブレード部１２１の設置を省略した場合である。
【００４５】
図１１ＡおよびＢは、実施例４、５および実施例６、対比例２に対するそれぞれの前述したＤＯ測定に基く、ＤＯ最大測定値の測定結果と走行時間との関係を示したものであり、図１２は、参照例３および４に対する同様の関係を示したものである。
【００４６】
図１１と図１２とを比較して明らかなように、磁気記録媒体の両面に対して第１および第２の爬掻ブレード部１２１および１２２を配置した本発明構成によれば、いづいれか一方のみを設けた場合に比し、格段的に走行時間に対するＤＯの改善が図られる。
【００４７】
特に、本発明による実施例４〜６によれば、長時間シャトル試験で２０００時間走行を行っても６ｄＢ５０μｓのＤＯが、最大１分当たり５個以下という以下という結果が得られた。
これに対し、仰角を大きくした対比例２は、実施例４〜６に比しては劣り、殊に、第１および第２の爬掻ブレード部１２１および１２２のいずれか一方のみが設けられた参照例３および４は、６ｄＢ５０μｓのＤＯが、最大１分当たり５個にとどめ得る走行時間は、１０００時間にも満たない。
すなわち、これら結果によれば、仰角θが１５°〜７５°においてクリーニング効果を長時間維持することができることが分かる。
【００４８】
上述したように、磁気記録媒体Ｍの両面に対してそれぞれクリーニング用の爬掻ブレード部１２１および１２２を配置した構成とし、更に望ましくは、その仰角θを１５°〜７５°とするときは、クリーニング効果を高め、かつその効果の長時間維持を可能にするものである。
【００４９】
次に、第３の実施の形態について説明する。
上述した第２の実施の形態においては、第１および第２の爬掻ブレード部１２１および１２２を配置するものの、磁気記録媒体Ｍの順方向および逆方向に対し、一方のみを動作させる構成としたものである。
これに対し、第３の実施の形態においては、第１および第２の爬掻ブレード部１２１および１２２において、磁気記録媒体Ｍの順方向および逆方向の双方に関してそれぞれ同時に各ブレードＢが磁気記録媒体Ｍの磁性層側の面ｆｍ　と背面側の面ｆｂ　とに対して、摺接して良好に摺接粉の取り除きを行うことができる構成とする。
【００５０】
〔第３の実施の形態〕
この実施の形態においては、図１３にその一例の概略配置を示すように、この実施の形態においても走行する磁気記録媒体Ｍに対して、摺接粉を排除するクリーニング機構１２０を具備する磁気記録再生装置とした場合である。
この例においても、ＶＴＲを例示したものであり、磁気ヘッド１が、回転磁気ヘッド装置１１として構成されているものであり、図１３において、図１および図６と対応する部分には同一符号を付して重複説明を省略する。
【００５１】
また、この実施の形態においても、図１３に示すように、そのクリーニング機構１２０が、回転磁気ヘッド装置１１に対する磁気記録媒体Ｍの移行途上の、記録または／および再生時の順方向移行方向に関する磁気ヘッド装置１１より手前側と後方側とに、それぞれ例えばサファイアブレードより成る爬掻ブレードＢを有する第１の爬掻ブレード部１２１と第２の爬掻ブレード部１２２とが配置された構成とされる。
【００５２】
しかしながら、この実施の形態においては、これら第１および第２の爬掻ブレード部１２１および１２２が、共にそれぞれ複数の爬掻ブレードＢ、図１３の例では、それぞれ第１および第２の２個の爬掻ブレードＢ１ａおよびＢ１ｂ　，Ｂ２ａおよびＢ２ｂが設けられて成る。
第１のブレード部１２１において、第１と第２の爬掻ブレードＢ１ａとＢ１ｂとが、共通の可動ブレード支持部、例えば回転軸６１で回動するブレード支持部３３１に支持され、また第２のブレード部１２２において、第１と第２の爬掻ブレードＢ２ａとＢ２ｂとが、共通の可動ブレード支持部例えば回転軸６２で回動するブレード支持部３３２に支持される。
【００５３】
そして、各ブレード支持部３３１および３３２の回動位置の選定によって図１４Ａに示すように、順方向ＦＷＤ方向に進行する磁気記録媒体Ｍの磁性層側の面ｆｍ　と背面側の面ｆｂ　とに対して、両第１および第２の爬掻ブレード部１２１および１２２の各一方の爬掻ブレードＢ１ａとＢ２ａとが、それぞれ第２の実施の形態において説明したと同様の所要の仰角θ、望ましくは前述した１５°〜７５°の角度をもって摺接させる。すなわち、この実施の形態においては、第１および第２の爬掻ブレード部１２１および１２２を、磁気記録媒体Ｍの両移行方向に対してブレードを摺接させる構成（以下両方摺接可動構成という）とする。
【００５４】
また、各ブレード支持部３３１および３３２の他の回動位置によって図１４Ｂに示すように、逆方向ＢＷＤ方向に進行する磁気記録媒体Ｍの磁性側面ｆｍ　と背面側の面ｆｂ　とに対して、各他方の爬掻ブレードＢ１ｂおよびＢ２ｂが、同様に、それぞれ第２の実施の形態において説明したと同様の所要の仰角θ、望ましくは前述した１５°〜７５°の角度をもって摺接させる。
【００５５】
この第３の実施の形態では、磁気記録媒体Ｍの順方向ＦＷＤおよび逆方向ＢＷＤの両方向に関して磁性層側ｆｍ　と背面側ｆｂ　とに、それぞれ所要の仰角θをもって爬掻ブレードＢが摺接するものであるので、摺接粉の排除をより確実に行うことができ、より信号のドロップアウトの発生を有効に回避することができるものである。
【００５６】
この場合においても、この本発明による実施形態における実施例、対比例と、本発明によらない参照例を挙げ、それぞれについてクリーニング効果の確認を行った。その方法は、図９にその作業のフローによる長時間シャトルＤＯ測定を、図１０で説明したと同様のシステムのよって行った。
【００５７】
〔実施例７〕
この実施例は、図１３で示した両方向摺接可動構成としたクリーニング機構１２０において、第１および第２の爬掻ブレード部１２１および１２２を、磁気記録媒体ＭのＦＷＤおよびＢＷＤの両方向に対してそれぞれのブレードが摺接するようにした場合で、第１の爬掻ブレード部１２１については、θ＝７５°とし、第２のブレード部１２２についてはθ＝１５°とした場合である。
【００５８】
〔実施例８〕
この実施例は、図１３で示した両方向摺接可動構成としたクリーニング機構１２０において、第１および第２の爬掻ブレード部１２１および１２２を、磁気記録媒体ＭのＦＷＤおよびＢＷＤの両方向に対してそれぞれのブレードが摺接するようにした場合で、第１の爬掻ブレード部１２１については、θ＝１５°とし、第２のブレード部１２２についてはθ＝７５°とした場合である。
【００５９】
次に、第４の実施の形態を挙げて説明する。
この例においても、ＶＴＲを例示したものであり、磁気ヘッド１が、回転磁気ヘッド装置１１として構成されているものである。
この実施の形態においては、図１５にその概略構成を示すように、この実施の形態においても、走行する磁気記録媒体Ｍに対して、摺接粉を排除するクリーニング機構１２０を具備する磁気記録再生装置とした場合であるが、この実施の形態においては、そのクリーニング機構１２０が、回転磁気ヘッド装置１１に対する磁気記録媒体Ｍの移行途上の、記録または／および再生時の順方向移行方向に関する磁気ヘッド装置１１より手前側において、磁気記録媒体Ｍの磁性層側に対する摺接粉の除去を行う構成とした場合である。
【００６０】
すなわち、この例においては、いわば、図１３における第２の爬掻ブレード部１２２が省略され、第１の爬掻ブレード部１２１による構成を有して成る。
この実施の形態においても、図１５に示すように、そのブレード部１２１が、それぞれ例えばサファイアブレードより成る第１および第２の２個の爬掻ブレードＢ１ａおよびＢ１ｂが設けられて成る。
これら爬掻ブレードＢ１ａとＢ１ｂは、共通の可動ブレード支持部、例えば回動するブレード支持部３３１に支持される。
図１５において、図１３と対応する部分には同一符号を付して重複説明を省略する。
【００６１】
そして、各ブレード支持部３３１の回動位置の選定によって図１６Ａに示すように、順方向ＦＷＤ方向に進行する磁気記録媒体Ｍの磁性層側の面ｆｍ　に対して、一方の爬掻ブレードＢ１ａが、前述した所要の仰角θ、望ましくは前述した１５°〜７５°の角度をもって摺接させる。
【００６２】
また、ブレード支持部３３１の他の回動位置の選定によって図１６Ｂに示すように、逆方向ＢＷＤ方向に進行する磁気記録媒体Ｍにおいては、その同様の磁性側面ｆｍ　に対して、他方の爬掻ブレードＢ１ｂが、同様に、前述したと同様の所要の仰角θ、望ましくは前述した１５°〜７５°の角度をもって摺接させる。
【００６３】
この第４の実施の形態においては、磁気記録媒体Ｍの順方向および逆方向の両方向の移行において、磁性層側の面ｆｍ　に対して爬掻ブレードＢ１ａ，Ｂ１ｂの一方が所要の仰角で摺接する構成としたことによって摺接粉の除去が効果的になされ、ドロップアウトが良好に改善される。
【００６４】
この第４の実施の形態の実施例を挙げる。
〔実施例９〕
この実施例は、図１５で示した両方向摺接可動構成としたクリーニング機構１２１において、爬掻ブレード部１２１の爬掻ブレードＢ１ａをＢ１ｂを、上述した仰角θが７５°となる角度をもって図１６ＡおよびＢに示すように、磁気記録媒体Ｍの両方向ＦＷＤとＢＷＤにおいて、摺接させた。
【００６５】
更に、参照例５〜７を用意した。
〔参照例５〕
図１５の本発明装置に対応する構成とするものの、そのクリーニング機構１２０を単一のブレードのみによって仰角θ＝７５°の固定構造とし、磁気記録媒体Ｍの順方向ＦＷＤ方向すなわち片側方向においてのみ磁性層側ｆｍ　にのみ摺接するようにした。
【００６６】
〔参照例６〕
図１５において、クリーニング機構１２０を用いない構造とした。
【００６７】
〔参照例７〕
図１３におけるように、回転磁気ヘッド装置１１に対する磁気記録媒体Ｍの移行途上の、記録または／および再生時の順方向移行方向に関する磁気ヘッド装置１１より手前側と後方側とに、それぞれ同様のサファイアブレードより成る爬掻ブレードＢを有する第１の爬掻ブレード部と第２の爬掻ブレード部とを配置する構成とするのの、これら爬掻ブレード部を、それぞれ片側方向にのみ摺接する可動構成とした場合である。
【００６８】
表３に、実施例７〜９と、参照例５〜６の構成を比較して示す。そして、これら例について、図１７Ａに実施例８および９を、図１７Ｂに実施例７を、図１８に参照例５〜７を、それぞれ、前述したと同様の方法によって測定したＤＯ測定の、走行時間との関係の測定結果を示す。これによれば、第４の実施の形態による実施例７〜９においても、２０００時間に及ぶ走行時間に関して良好に、ＤＯの改善が図られることが分かる。
【００６９】
【表３】

【００７０】
尚、本発明装置は、上述したような例に限定されるのではなく、本発明の要旨を逸脱することなく種々の構成を採り得る。
【００７１】
【発明の効果】
上述したように、本発明装置によれば、磁気記録媒体の磁気ヘッドや、ガイド、キャプスタン、ピンチローラ等との接触ないしは磁性粉の剥脱物や、この摺動等によって付着した不安定な塵埃等の摺接粉を、効果的に排除することができることから、正常な信号の書き込みや再生出力信号の取出しの阻害を回避でき、例えばＶＴＲにおいて、良好な音質と、画質を保持することができる。
また、本発明装置によれば、安定して、多頻度、多数回に渡って、磁気記録媒体の繰り返し使用を可能にすると共に、磁気ヘッドの耐用寿命の長期化を図ることができるものである。
【００７２】
上述したように、本発明装置によれば、クリーニング効果の向上および長時間維持により、記録再生に関する特性保証が向上し、信頼性の向上が図られる。
したがって、本発明装置にほれば、塗布型磁気記録媒体に比し、すぐれた電磁変換特性を生かした金属薄膜型磁気記録媒体の小型、高密度化のフォーマットの実現を、技術的により容易にするのみならず、異なるフォーマットへも応用が可能となるものである。
【００７３】
【図面の簡単な説明】
【図１】本発明による磁気記録再生装置の一例の概略配置図である。
【図２】本発明による磁気記録再生装置の一例の磁気ヘッドのクリーニング機構の一例の概略側面図である。
【図３】本発明による磁気記録再生装置の一例の磁気ヘッドのクリーニング機構の一例のクリーニング状態における概略配置図である。
【図４】出力減衰量の測定のシステムの構成図である。
【図５】長時間シャトル耐久性におけるテープ巻数と、出力減衰量の測定結果を示す図である。
【図６】本発明による磁気記録再生装置の他の一例の概略配置図である。
【図７】本発明装置のクリーニング機構の一例の要部を示す図である。
【図８】本発明装置のクリーニング機構の一例の磁気記録媒体に対する摺接・離間の関係を示す図である。
【図９】本発明装置のクリーニング機構の評価のためのドロップアウト測定のフロー図である。
【図１０】ドロップアウト測定のシステムの構成図である。
【図１１】Ａは、本発明の実施例のドロップアウト測定と走行時間との関係を示す図である。Ｂは、本発明の実施例および対比例のドロップアウト測定と走行時間との関係を示す図である。
【図１２】参考例のドロップアウト測定と走行時間との関係を示す図である。
【図１３】本発明による磁気記録再生装置の他の一例の概略配置図である。
【図１４】ＡおよびＢは、それぞれ本発明装置のクリーニング機構の一例の各動作状態の説明図である。
【図１５】本発明による磁気記録再生装置の他の一例の概略配置図である。
【図１６】ＡおよびＢは、それぞれ本発明による磁気記録再生装置の更に他の一例のクリーニング機構の各動作状態の説明図である。
【図１７】ＡおよびＢは、本発明の実施例のドロップアウト測定と走行時間との関係を示す図である。
【図１８】参考例のドロップアウト測定と走行時間との関係を示す図である。
【図１９】本発明の説明に供する磁気ヘッドに対するクリーニングローラとブレードとの関係の説明図である。
【図２０】本発明の説明に供する磁気記録媒体と爬掻ブレードとの関係の説明図である。
【符号の説明】
１・・・磁気ヘッド、２，１２０・・・クリーニング機構、３・・・固定ドラム、４・・・回転ドラム、５・・・クリーニングローラ部、６・・・爬掻ブレード部、７・・・引っ張りばね、、８・・・クリーニングローラ支持部、９・・・軸、１０・・・１０・・・飛散防止板、１１・・・回転磁気ヘッド装置、Ｒｃ・・・爬掻ブレード、１３・・・ブレード支持部、１４・・・テープカセット、１５・・・供給リール、１６・・・巻取りリール、１７・・・回転ガイド、１８・・・固定ガイド、１９・・・キャプスタン、２０・・・ピンチローラ、６１，６２・・・回転軸、１１１・・・ＶＴＲ、１１２・・・制御用コンピュータ、１１３・・・オシロスコープ、１１４・・・ＤＯカウンタ、１１５・・・記録計、１２１・・・第１の爬掻ブレード部、１２２・・・第２の爬掻ブレード部、２０１・・・ＶＴＲ、２０２・・・制御用コンピュータ、２０３・・・検波回路、２０４・・・記録計、３３１，３３２ブレード支持部、Ｂ・・・爬掻ブレード、Ｂｆ・・・前方刃面、Ｂｂ・・・後方刃面、Ｍ・・・磁気記録媒体、ｆｍ　・・・磁性層側の面、ｆｂ　・・・背面側の面、Ｂ１ａおよびＢ１ｂ　，Ｂ２ａおよびＢ２ｂ・・・ブレード[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is directed to, for example, contamination of a magnetic head, a magnetic recording medium, and the like with dust (hereinafter referred to as sliding contact powder) generated or adhered by sliding contact with various parts of a magnetic recording medium or the like in the present specification. The present invention relates to a magnetic recording / reproducing apparatus (hereinafter, simply referred to as a magnetic recording / reproducing apparatus) for performing magnetic recording and / or reproducing in which the occurrence of a dropout of a reproduction output, an error, and the like due to the above are improved.
[0002]
[Prior art]
In a magnetic recording / reproducing apparatus such as a video tape recorder (VTR), high-density recording is more strongly required in order to achieve high image quality and long-time recording.
When a magnetic recording medium is used as a recording medium, a so-called metal magnetic thin film type magnetic recording medium is suitable for high-density recording.
[0003]
This metal magnetic thin film type magnetic recording medium has not only excellent coercive force, squareness ratio and electromagnetic conversion characteristics in a short wavelength region than a so-called coating type magnetic recording medium obtained by coating a magnetic material, but also has a thin magnetic layer. Magnetic demagnetization and extremely small thickness loss during reproduction, and the fact that there is no need to mix a non-magnetic material binder into the magnetic layer as in a coating type. It has many advantages such as a higher packing density of the material.
[0004]
Further, the magnetic recording medium has various shapes such as a disk shape and a tape shape depending on the recording / reproducing device used. In these cases, the quality of the apparatus is determined by the fact that the recording / reproducing magnetic head always traces the track pattern recorded on the magnetic layer accurately and can record and reproduce the recording signal accurately. That is, for example, in the case of a configuration in which recording and / or reproduction is performed by a rotary head, an important point in maintaining a stable state of the contact state between the rotary head and the magnetic recording medium without being affected by disturbance or the like. become.
[0005]
In particular, in the metal thin film type configuration, the electromagnetic conversion characteristics are superior to the coating type configuration. Therefore, by performing short-wavelength recording, it is possible to easily achieve a smaller size and a higher density. For example, the track pitch in the recording pattern is reduced. However, the use of short-wavelength recording is more susceptible to disturbances and the like.
Therefore, when the magnetic recording medium, for example, a magnetic tape runs, sliding contact powder due to sliding between the magnetic recording medium and each part is transferred to the magnetic head, and the sliding contact powder is transferred between the magnetic tape and the magnetic head. In this case, there is a problem that spacing loss occurs, attenuation of reproduction output, so-called dropout occurs, and it becomes difficult to maintain stable normal recording and reproduction.
The transfer of the sliding contact powder to the magnetic head has a greater effect on the characteristics when a magnetoresistive magnetic head is applied.
[0006]
In order to eliminate such sliding powder transferred to the magnetic head, for example, in a VTR, a magnetic tape is guided and run on a rotating drum equipped with a magnetic head as in a tape guide running system for the magnetic tape. A cleaning roller is provided at a position opposite to the side, that is, at a position where the magnetic tape does not contact the magnetic head. In some cases, the sliding contact powder attached to the magnetic head is transferred and removed.
However, also in this case, the sliding contact powder transferred to the cleaning roller due to frequent use for a long time not only reduces the elimination effect from the magnetic head but also conversely causes the sliding contact powder adhered to the cleaning roller. Is transferred to the magnetic head again.
[0007]
Also, sliding contact powder remaining on the surface of a magnetic recording medium, for example, a magnetic tape, is transferred to a guide roller or the like, and is again transferred to a magnetic head when recording, reproducing, or rewinding. Therefore, it is necessary to remove the sliding powder on the surface of the magnetic tape.
To cope with this problem, a blade that slides on the surface of the magnetic tape on the magnetic layer side to scrape off the sliding contact powder, that is, a scraping blade is provided.
However, even when the magnetic layer side is scraped with respect to the sliding contact powder in this manner, for example, in a state in which the magnetic tape is wound on the supply reel or the take-up reel, the magnetic layer side and the back side opposite to the magnetic layer side are separated. Since it is in a contact state, the sliding contact powder on the magnetic layer side is transferred to the back side, or the sliding contact powder transferred on the back side is further transferred to the magnetic layer side. Improvement of the problem is not always enough.
[0008]
[Problems to be solved by the invention]
In the present invention, it is possible to effectively eliminate the above-described problems such as a decrease in reproduction output and dropout caused by dust caused by sliding contact powder, for example, separation from a magnetic recording medium or transfer from another part. An object of the present invention is to provide a magnetic recording / reproducing apparatus for performing magnetic recording and / or reproduction.
[0009]
[Means for Solving the Problems]
The present invention includes a cleaning mechanism for scraping off the sliding contact powder of the magnetic recording medium.
In the magnetic recording / reproducing apparatus according to the present invention, the cleaning mechanism includes a cleaning roller that comes into contact with and separates from the magnetic head, and a scraping blade, and the scraping blade has a cutting edge along the axial direction of the cleaning roller. The ridge extends, and the blade is slidable along the peripheral surface of the cleaning roller by the rotation of the cleaning roller.
In this way, the sliding powder such as the magnetic layer of the magnetic recording medium transferred from the magnetic head to the cleaning roller is scraped off by the scraping blade, and the sliding powder is transferred from the cleaning roller to the magnetic head again. Avoid being worn.
[0010]
When the scraping blade in this configuration is in sliding contact with the cleaning roller, as shown in FIG. 19, the blade surface Bf on the front side of the scraping blade B in the rotation direction indicated by the arrow a of the cleaning roller Rc (hereinafter, this front side) Is referred to as a front blade surface, and a blade surface Bb on the opposite side is referred to as a rear blade surface) with respect to a tangent line b at a sliding contact portion with respect to a peripheral surface of the cleaning roller Rc (hereinafter, this angle is an elevation angle). Is preferably selected in the range of 30 ° to 60 °.
[0011]
Further, in the magnetic recording / reproducing apparatus according to the present invention, the cleaning mechanism may be arranged such that, during the transition of the magnetic recording medium with respect to the magnetic head, the cleaning mechanism is disposed on the front side and the rear side with respect to the magnetic head in the forward transition direction during recording or / and reproduction, respectively. The first and second scraping blade portions are arranged and each have a scraping blade.
[0012]
In the first and second repelling blade portions, at least in the forward direction transition, the blade of the first repelling blade portion is slid in contact with the magnetic layer side, and at least in the reverse direction transition, The blade is configured to slide on the back side of the magnetic recording medium.
Alternatively, the first and second scraping blade portions change the inclinations of the blades that are in sliding contact with the magnetic layer side and the back side of the magnetic recording medium, respectively, in the forward transition and the backward transition, and respectively change the respective inclinations. Is selected to have an inclination suitable for the scraping of the sliding powder.
Further, or alternatively, the first and second scraping blade portions have a configuration having a plurality of blades, and slide the selected blade toward the magnetic layer side and the rear surface side when the magnetic recording medium moves forward and backward, respectively. By contacting the magnetic layer and the blade that slides on the back surface, the transition direction of the blade is selected to be suitable for the scraping of the sliding powder.
[0013]
As shown in FIG. 20A, the inclination suitable for the scraping of the sliding contact powder means that the front blade surface Bf on the front side in the moving direction of the magnetic recording medium with respect to the scraping blade is closer to the sliding contact position with the magnetic recording medium. The inclination of the rear magnetic recording medium with respect to the medium surface, that is, the elevation angle θ is an acute angle. That is, as shown in FIG. 20B, when the elevation angle θ is an obtuse angle, the sliding powder is taken in between the blade and the magnetic recording medium, and the sliding powder is re-attached to the magnetic recording medium. It does not have a tilt suitable for scraping of powder.
The elevation angle θ is desirably 15 ° to 75 °.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the device of the present invention will be described by way of example, but the present invention is not limited to this example.
[First Embodiment]
In this embodiment, as shown in FIG. 1, a cleaning mechanism 2 for cleaning a sliding contact powder transferred to a magnetic head 1 by a magnetic recording medium slidingly contacting the magnetic head 1 is shown in FIG. This is a case where the present invention is applied to a magnetic recording / reproducing apparatus provided.
In the example of FIG. 1, a VTR (Video Tape Recorder) is exemplified, and the magnetic head 1 is configured as a rotating magnetic head device 11.
As shown in a schematic side view of an example in FIG. 2, the rotary magnetic head 11 device has a fixed drum 3 and a rotary drum 4 arranged concentrically, and the magnetic head 1 is disposed on the rotary drum 4. It is the configuration which was done.
[0015]
The cleaning mechanism 2 includes a cleaning roller unit 5 and a scraping blade unit 6.
The cleaning roller unit 5 is configured such that a cleaning roller Rc whose peripheral surface is formed of, for example, a polyurethane foam resin is supported on the cleaning roller support unit 8. The support portion 8 has an arm that is movable, for example, as shown in FIG. 1, and is rotatably supported about a shaft 9. For example, a cleaning roller Rc is rotatably supported at its free end. You.
The scraping blade section 6 has a scraping blade B. The scraping blade B is formed of, for example, a sapphire blade, and this is supported by the blade support portion 13 and fixed at a predetermined position, for example.
[0016]
On the other hand, a magnetic tape, that is, a magnetic recording medium M is fed out from a supply reel 15 in the tape cassette 14 and guided by a rotating guide 17, a fixed guide 18 and the like, respectively. The transfer is made obliquely around the peripheral surface, and is sandwiched by the drive mechanism, that is, the capstan 19 and the pinch roller 20, and is controlled at a predetermined transfer speed to be taken up by the take-up reel 16 in the tape cassette 14. Is made.
Thus, in the rotating magnetic head device 11, the magnetic head 1 slides on the magnetic tape to perform recording or reproduction.
[0017]
The cleaning roller Rc is brought into contact with or separated from the magnetic head 1 by the rotation of the support portion 8 at a position of the rotating magnetic head device 11 where the magnetic head 1 is not in contact with the magnetic recording medium M.
On the other hand, the cleaning roller Rc is separated from the scraping blade B at the contact position with the magnetic head 1. Further, at a position separated from the magnetic head 1, as shown in a schematic plan view of a main part in FIG.
For example, a tension spring 7 is engaged with the support portion 8 of the cleaning roller Rc so that the cleaning roller Rc contacts the scraping blade B with a required contact pressure.
[0018]
In this configuration, the cleaning roller Rc is brought into contact with the rotating magnetic head device 11, that is, the magnetic head 1 for about several seconds at the time of switching the running mode such as the rewinding state of the magnetic recording medium M after recording or reproduction, for example. Due to this contact, deposits on the magnetic head 1 are removed by the cleaning roller Rc. At this time, since the magnetic head 1 is rotating at a high speed, the cleaning roller Rc is rotated at a high speed accordingly.
From this state, the cleaning roller Rc is separated from the rotating magnetic head device 11 by the support portion 8. At this time, the cleaning roller Rc is rotated by inertia and comes into contact with the fixed scraping blade B, and the scraping blade B removes the deposit on the cleaning roller Rc.
[0019]
In front of the contact portion of the scraping blade B with the cleaning roller Rc, a scattering prevention plate 10 for preventing scattering of the scraped sliding contact powder is disposed.
[0020]
As shown in FIG. 3, the contact between the cleaning roller Rc and the scraping blade B increases the elevation angle θ of the blade surface on the front side of the blade B in the rotation direction indicated by the arrow a of the cleaning roller Rc, that is, the front blade surface Bf by 30 °. Select within the range of ６０60 °.
[0021]
With the above configuration, the sliding contact powder adhering to the magnetic head 1 due to the contact of the rotating magnetic head device 11 with the magnetic head 1 is transferred to the cleaning roller Rc, and the magnetic head 1 is cleaned.
Then, in the apparatus of the present invention, since the sliding powder transferred to the cleaning roller Rc is scraped off by the scraping blade B, the cleaning operation for the magnetic head 1 by the same cleaning roller Rc is frequently performed. Even if the cleaning is performed for a long time, the cleaning roller Rc itself is contaminated by the sliding contact powder from the magnetic head, and the cleaning effect on the magnetic head 1 is reduced or lost. This eliminates the risk of transfer to the device.
[0022]
One guideline of the head cleaning effect of the cleaning roller in the cleaning mechanism is that the reproduction output attenuation is within 3 dB during continuous operation for 2000 hours.
[0023]
The cleaning effect was confirmed for each of the examples, comparative examples, and reference examples not according to the present invention. In this method, a first-time test magnetic tape having a length corresponding to one hour is passed once through the magnetic head without using any cleaning tape used for cleaning the magnetic head. A shuttle test was performed in which a total of 100 passes were made by repeating the recording on the magnetic tape 99 times, and after this test, a similar shuttle test was performed on the new second test magnetic tape. A test is performed, and the same test is repeated for a total of 20 magnetic tapes. In this way, a test corresponding to continuous running for substantially 2000 hours (hereinafter, this method is referred to as a long-time shuttle durability test) was performed on the magnetic head. The output attenuation was determined for the magnetic heads subjected to this test.
[0024]
FIG. 4 shows a configuration diagram of a system for measuring the output attenuation. In this case, a DCR-VX1000 manufactured by Sony, which is a 6.35 mm wide digital video recorder for consumer use, is used as the VTR 201, and a cleaning mechanism 2 provided with a scraping blade B capable of changing the elevation angle θ with respect to the cleaning roller Rc is arranged on the DCR-VX1000. did.
As the magnetic tape, a commercially available Sony cassette tape was used.
Control of one-pass recording and 99-pass continuous reproduction in the VTR 201 was performed by modifying a commercially available remote control RM-95 made by Sony and connecting a personal computer 202.
From the RF reproduction signal obtained by the VTR 201, an envelope signal, which is an AC / DC (DC / AC) conversion, was obtained by a detection circuit 203, and this was recorded on a recorder 204, and an output attenuation from an initial output was obtained. Reference numeral 205 denotes a power supply unit such as a detection circuit.
[0025]
[Example 1] to [Example 3]
In each embodiment, the elevation angle θ of the scraping blade B in the cleaning mechanism 2 shown in FIG. 1 was selected to be 30 °, 45 °, and 60 °.
[0026]
[Comparative 1]
In the above-described cleaning mechanism 2, the elevation angle θ of the scraping blade B was set to 90 °.
[Reference Example 1]
In the cleaning mechanism 2, the cleaning roller Rc was provided without providing the scraping blade portion 6.
[Reference Example 2]
No cleaning mechanism was provided. That is, the cleaning roller and the scraping blade were not provided.
[0027]
For these Examples 1 to 3, Comparative Example 1, and Reference Examples 1 and 2, the output attenuation was measured by the above-described measurement method based on the long-term shuttle durability described above. Table 1 shows the measurement results.
[0028]
[Table 1]

[0029]
According to this, in Examples 1 to 3 in which the elevation angle θ was 30 ° to 60 °, the output attenuation was able to be kept to 3 dB or less in all 20 tape passes.
In contrast, the durability of Comparative Example 1 is inferior to those of Examples 1 to 3. In Reference Examples 1 and 2, the output attenuation of 3 dB or less could be achieved only by the pass of eight or three turns.
[0030]
On the other hand, FIG. 5 shows the measurement results of the number of tape windings and the output attenuation in the above-described 100 passes in the long-term shuttle durability. In FIG. 5, curves 51, 52, and 53 are curves according to the first, second, and third embodiments, curve 54 is a curve according to the first comparative example, and curves 55 and 56 are curves of the first and second reference examples. Is the case.
[0031]
As is clear from Table 1 and FIG. 5, according to the device of the present invention, particularly the elevation angles θ of Examples 1 to 3 in which the elevation angle θ is 30 ° to 60 °, the output attenuation is significantly improved, It can be seen that the powder contact has been satisfactorily cleaned from the magnetic head over a long period of time.
[0032]
[Second embodiment]
In this embodiment, as shown in a schematic layout diagram of one example in FIG. 6, a magnetic recording / reproducing apparatus having a cleaning mechanism 120 for removing sliding contact powder from a running magnetic recording medium M is provided. It is.
Also in this example, a VTR is illustrated, and the magnetic head 1 is configured as a rotary magnetic head device 11, and in FIG. 6, portions corresponding to those in FIG. A duplicate description will be omitted.
[0033]
In this embodiment, as shown in FIG. 6, the cleaning mechanism 120 is provided with a magnetic head device in the direction of the forward transition during recording or / and reproduction during the transition of the magnetic recording medium M to the rotary magnetic head device 11. A first scraping blade portion 121 and a second scraping blade portion 122 each having a scraping blade B made of, for example, a sapphire blade are arranged on the front side and the rear side of 11.
[0034]
Each of the first and second scraping blade portions 121 and 122 has a configuration in which a scraping blade B is supported by a blade support portion 23 as shown in a rear view of FIG.
FIG. 8 is a schematic plan view showing the positional relationship between the blades B of the first and second scraping blade portions 121 and 122 with respect to the magnetic recording medium M. One main surface fm of the magnetic recording medium M is This is the surface on the side having the magnetic layer, and the other main surface fb is the surface on the back side. 8, in the magnetic recording medium M, the rightward transition is a transition during reproduction and recording, that is, a forward transition (FWD), and the reverse rewind transition in the opposite direction is a forward transition (FWD). (BWD).
[0035]
Each of the blade supporting portions 23 of the first and second scraping blade portions 121 and 122 supports the scraping blade B in a movable manner, for example, in a rotating manner. By this rotation, each scraping blade B slides and separates from the surface fm on the magnetic layer side and the back surface fb of the magnetic recording medium M as indicated by solid lines and chain lines, respectively.
In other words, when the magnetic recording medium M is in the forward transition FWD state, the rotation of the support portion 23 causes the scraping blade B of the first scraping blade portion 121 to move as shown by the solid line in FIG. The scraping blade B of the second scraping blade portion 122 is slidably in contact with the surface fm on the magnetic layer side of the recording medium M, and is separated from the back surface fb of the magnetic recording medium M.
Conversely, when the magnetic recording medium M is in the state of backward transition BWD, the scraping blade B of the first scraping blade section 121, as shown by a chain line in FIG. The second scraping blade portion 122 is separated from the magnetic layer side surface fm of the magnetic recording medium M, and slides on the rear surface side fb of the magnetic recording medium M.
[0036]
The width of each of the scraping blades B of the first and second scraping blade portions 121 and 122 is a magnetic recording medium, that is, a magnetic tape such that the width of each of the scraping blades B can slide over the entire width of the magnetic recording medium M. Is selected to be larger than the width of
The elevation angle θ of these scraping blades B with respect to the respective surfaces fm and fb of the magnetic recording medium M is desirably selected in the range of 15 ° to 75 °.
[0037]
According to the magnetic recording / reproducing apparatus of this embodiment, scraping of the sliding contact powder, that is, squeezing is performed not only on the surface fm on the magnetic layer side but also on the back surface fb of the magnetic recording medium. As a result, a defect that causes a loss of mobility signal, that is, a dropout, is effectively removed.
In other words, even if the sliding contact powder is transferred to the back side of the magnetic recording medium M for any cause, for example, sliding contact with another, or entrainment of the magnetic recording medium M on the reel, the second repeller may be used. The scraping powder on the back side is removed by the scraping blade portion 122, thereby effectively preventing the magnetic head from being stained or the magnetic recording medium from being stained by the sliding contact powder, thereby effectively preventing signal dropout. Is what you can do.
[0038]
Also in this case, as one measure of the cleaning effect by the cleaning mechanism 120, if an increase in dropout that causes heterogeneous failure during continuous operation for 2000 hours is not observed, a good apparatus as a magnetic recording / reproducing apparatus is considered. can do.
[0039]
The cleaning effect was confirmed for each of the examples, comparative examples, and reference examples not according to the present invention. As shown in the flow of the operation in FIG. 9, the method is to record a full-length record of the first run of the test magnetic tape having a length corresponding to one hour without using any cleaning tape. Then, dropout measurement (hereinafter referred to as DO measurement) over the entire length was performed as a second run. After performing 97 times of continuous repetitive reproduction, that is, after performing the 98th run, in the 99th run, DO measurement was performed over the entire length. Next, the same operation was performed for the same test magnetic tape of the second volume, and the same operation was performed for the magnetic tapes of all 20 volumes. DO measurement).
[0040]
FIG. 10 shows a configuration diagram of this DO measurement system. Here, Sony's DHR-1000 which is a 6.35 mm wide digital video recorder for consumer use is used as the VTR 111, and first and second scraping blade portions 121 and 122 are provided in the DTR-1000. The elevation angle θ can be changed.
The magnetic tape used was a commercially available Sony cassette tape. For the shuttle running of the VTR, a commercially available Sony remote control RM-95 was modified and connected to the personal computer 112 to control the VTR 111. Further, the RF (high frequency) reproduced signal waveform and the switching pulse waveform signal of the VTR 111 are introduced into the oscilloscope 113, and furthermore, are taken into a commercially available DO counter 114 (Shibasoku: VH06AZ), and the DO amount of the reproduced signal is measured. For example, we asked for output through a printer. Here, the DO measurement size is based on -6 dB50 μs related to image quality failure, and the maximum is 5 or less per minute.
[0041]
[Example 4] to [Example 6]
In each embodiment, as shown in FIG. 6, a cleaning mechanism 2 having first and second scraping blade portions 121 and 122 is provided. As shown in Table 2, the first scraping blade portion is provided. The elevation angle θ of the blade B of the second scraping blade portion 122 was set to 15 °, 45 °, and 75 °, respectively.
[0042]
[Table 2]

[0043]
[Comparative 2]
As in the case of the fourth to sixth embodiments, the first and second scraping blade portions 121 and 122 are provided, but the elevation angle θ of the blade B of the second scraping blade portion 122 is set to 90 °.
[0044]
[Reference Example 3]
In this example, the installation of the second scraping blade section 122 is omitted.
[Reference Example 4]
In this example, the installation of the first scraping blade section 121 is omitted.
[0045]
11A and 11B show the relationship between the measurement result of the maximum DO measurement value and the travel time based on the above-described DO measurement for Examples 4, 5, and 6, and Comparative Example 2, respectively. Reference numeral 12 indicates a similar relationship to Reference Examples 3 and 4.
[0046]
As is apparent from a comparison between FIGS. 11 and 12, according to the configuration of the present invention in which the first and second scraping blade portions 121 and 122 are arranged on both surfaces of the magnetic recording medium, Compared with the case where only the vehicle is provided, the DO is significantly improved with respect to the traveling time.
[0047]
In particular, according to Examples 4 to 6 according to the present invention, even after running for 2,000 hours in the long-time shuttle test, the following results were obtained: the DO of 6 dB50 μs was 5 or less per minute at maximum.
On the other hand, Comparative Example 2 in which the elevation angle was increased was inferior to Examples 4 to 6, and in particular, only one of the first and second scraping blade portions 121 and 122 was provided. In Reference Examples 3 and 4, the travel time in which a 6 dB 50 μs DO can be reduced to a maximum of 5 DOs per minute is less than 1000 hours.
That is, according to these results, it is understood that the cleaning effect can be maintained for a long time when the elevation angle θ is 15 ° to 75 °.
[0048]
As described above, the cleaning blades 121 and 122 are disposed on both sides of the magnetic recording medium M. More preferably, when the elevation angle θ is 15 ° to 75 °, the cleaning is performed. The effect is enhanced, and the effect can be maintained for a long time.
[0049]
Next, a third embodiment will be described.
In the above-described second embodiment, the first and second scraping blades 121 and 122 are arranged, but only one of them is operated in the forward and reverse directions of the magnetic recording medium M. Things.
On the other hand, in the third embodiment, in the first and second scraping blade portions 121 and 122, each blade B is simultaneously moved in both the forward direction and the reverse direction of the magnetic recording medium M. The structure is such that the surface fm on the magnetic layer side and the surface fb on the back side of M are in sliding contact with each other so that the sliding contact powder can be satisfactorily removed.
[0050]
[Third Embodiment]
In this embodiment, as shown in FIG. 13, a schematic arrangement of an example is shown. In this embodiment, the magnetic recording medium M having the cleaning mechanism 120 for removing the sliding contact powder is also applied to the running magnetic recording medium M. This is a case where the playback device is used.
Also in this example, a VTR is illustrated, and the magnetic head 1 is configured as a rotating magnetic head device 11. In FIG. 13, portions corresponding to FIG. 1 and FIG. The description is omitted here.
[0051]
Also in this embodiment, as shown in FIG. 13, the cleaning mechanism 120 moves the magnetic recording medium M with respect to the rotary magnetic head device 11 while the magnetic recording medium M moves in the forward direction during recording or / and reproduction. On the front side and the rear side of the head device 11, a first repelling blade portion 121 and a second repelling blade portion 122 each having a repelling blade B made of, for example, a sapphire blade are arranged. .
[0052]
However, in this embodiment, both the first and second scraping blade portions 121 and 122 are each composed of a plurality of scraping blades B, and in the example of FIG. It is provided with scraping blades B1a and B1b, B2a and B2b.
In the first blade portion 121, the first and second scraping blades B1a and B1b are supported by a common movable blade support portion, for example, a blade support portion 331 that rotates about the rotation shaft 61, and the second In the blade unit 122, the first and second scraping blades B2a and B2b are supported by a common movable blade support unit, for example, a blade support unit 332 that rotates around the rotation shaft 62.
[0053]
By selecting the rotational position of each blade support 331 and 332, as shown in FIG. 14A, the surface fm on the magnetic layer side and the surface fb on the back side of the magnetic recording medium M traveling in the forward direction FWD direction. Each of the first and second scraping blade portions 121 and 122 has one of the scraping blades B1a and B2a, respectively, having the same required elevation angle θ as described in the second embodiment, and The sliding contact is made at an angle of 15 ° to 75 °. That is, in this embodiment, the first and second scraping blade portions 121 and 122 are configured so that the blades are slid in both transition directions of the magnetic recording medium M (hereinafter, both are slidably movable). And
[0054]
Further, as shown in FIG. 14B, with respect to the magnetic side surface fm and the back side surface fb of the magnetic recording medium M advancing in the reverse BWD direction by other rotation positions of the blade support portions 331 and 332, respectively. Similarly, the other scraping blades B1b and B2b are brought into sliding contact with each other at the required elevation angle θ similar to that described in the second embodiment, preferably at the above-mentioned angle of 15 ° to 75 °.
[0055]
In the third embodiment, the scraping blade B slides on the magnetic layer side fm and the back side fb with a required elevation angle θ in both the forward direction FWD and the reverse direction BWD of the magnetic recording medium M. As a result, the sliding contact powder can be more reliably eliminated, and the occurrence of signal dropout can be more effectively avoided.
[0056]
Also in this case, the cleaning effect was confirmed for each of the examples, comparative examples, and reference examples not according to the present invention. In this method, the long-time shuttle DO measurement according to the work flow in FIG. 9 was performed by the same system as described in FIG.
[0057]
[Example 7]
In this embodiment, in the cleaning mechanism 120 having the bidirectional sliding contact movable structure shown in FIG. 13, the first and second scraping blade portions 121 and 122 are moved in both directions of the FWD and the BWD of the magnetic recording medium M. In this case, the respective blades are in sliding contact with each other. In this case, θ = 75 ° for the first scraping blade portion 121 and θ = 15 ° for the second blade portion 122.
[0058]
Example 8
In this embodiment, in the cleaning mechanism 120 having the bidirectional sliding contact movable structure shown in FIG. 13, the first and second scraping blade portions 121 and 122 are moved in both directions of the FWD and the BWD of the magnetic recording medium M. In this case, the respective blades are in sliding contact with each other. In this case, θ = 15 ° for the first scraping blade portion 121 and θ = 75 ° for the second blade portion 122.
[0059]
Next, a fourth embodiment will be described.
Also in this example, a VTR is illustrated, and the magnetic head 1 is configured as a rotating magnetic head device 11.
In this embodiment, as schematically shown in FIG. 15, also in this embodiment, a magnetic recording / reproducing system provided with a cleaning mechanism 120 for removing sliding contact powder on a running magnetic recording medium M. In this embodiment, the cleaning mechanism 120 is provided with a magnetic head in the forward transition direction during recording or / and reproduction during the transition of the magnetic recording medium M to the rotary magnetic head device 11 in this embodiment. This is a case where the sliding powder is removed from the magnetic layer side of the magnetic recording medium M on the front side of the apparatus 11.
[0060]
That is, in this example, so-called, the second scraping blade portion 122 in FIG. 13 is omitted, and the first scraping blade portion 121 has a configuration.
Also in this embodiment, as shown in FIG. 15, the blade portion 121 is provided with first and second two scraping blades B1a and B1b each made of, for example, a sapphire blade.
These scraping blades B1a and B1b are supported by a common movable blade support, for example, a rotating blade support 331.
15, portions corresponding to those in FIG. 13 are denoted by the same reference numerals, and redundant description will be omitted.
[0061]
Then, as shown in FIG. 16A, one of the scraping blades B1a is moved relative to the surface fm on the magnetic layer side of the magnetic recording medium M advancing in the forward FWD direction by selecting the rotation position of each blade support portion 331. The sliding contact is made at the above-mentioned required elevation angle θ, preferably at the above-mentioned angle of 15 ° to 75 °.
[0062]
Further, as shown in FIG. 16B, by selecting another rotation position of the blade support portion 331, in the magnetic recording medium M that advances in the reverse BWD direction, the other magnetic side surface fm is opposed to the other magnetic side surface fm. Similarly, the blade B1b is slid in contact with the same required elevation angle θ as described above, preferably at the above-described angle of 15 ° to 75 °.
[0063]
In the fourth embodiment, one of the scraping blades B1a and B1b slides on the magnetic layer side surface fm at a required elevation angle in both the forward and reverse directions of the magnetic recording medium M. With this configuration, the sliding contact powder is effectively removed, and the dropout is improved satisfactorily.
[0064]
An example of the fourth embodiment will be described.
[Example 9]
In this embodiment, in the cleaning mechanism 121 having the two-way sliding contact movable structure shown in FIG. 15, the scraping blade B1a of the scraping blade portion 121 is set to B1b with the above-described elevation angle θ of 75 °. As shown in B, the magnetic recording medium M was slid in both directions FWD and BWD.
[0065]
Further, Reference Examples 5 to 7 were prepared.
[Reference Example 5]
Although the cleaning mechanism 120 has a configuration corresponding to the apparatus of the present invention shown in FIG. 15, the cleaning mechanism 120 has a fixed structure with an elevation angle θ = 75 ° using only a single blade, and the magnetic mechanism is magnetic only in the forward FWD direction of the magnetic recording medium M, that is, in one side direction. Sliding contact was made only with the layer side fm.
[0066]
[Reference Example 6]
In FIG. 15, the cleaning mechanism 120 is not used.
[0067]
[Reference Example 7]
As shown in FIG. 13, while the magnetic recording medium M is being transferred to the rotary magnetic head device 11, the same sapphire is provided on the front side and the back side of the magnetic head device 11 in the forward direction of the recording or / and reproduction, respectively. Although the first and second repelling blades having the repelling blade B composed of blades are arranged, a movable configuration in which the repelling blades are slidably contacted only in one direction respectively. Is the case.
[0068]
Table 3 shows a comparison between the configurations of Examples 7 to 9 and Reference Examples 5 and 6. 17A, FIG. 17B shows Example 7, FIG. 18 shows Reference Examples 5 to 7, and FIG. 17 shows Reference Examples 5 to 7, respectively. The measurement result of the relationship with time is shown. According to this, in Examples 7 to 9 according to the fourth embodiment, it is understood that DO can be improved satisfactorily with respect to a running time of 2000 hours.
[0069]
[Table 3]

[0070]
It should be noted that the device of the present invention is not limited to the example described above, but can adopt various configurations without departing from the gist of the present invention.
[0071]
【The invention's effect】
As described above, according to the apparatus of the present invention, contact with the magnetic head of the magnetic recording medium, the guide, the capstan, the pinch roller, or the like, or exfoliation of the magnetic powder, or unstable dust adhered by the sliding or the like And the like, can be effectively eliminated, so that it is possible to avoid obstruction of normal signal writing and reproduction output signal extraction. For example, in a VTR, good sound quality and image quality can be maintained. .
Further, according to the apparatus of the present invention, the magnetic recording medium can be used repeatedly stably, frequently and many times, and the useful life of the magnetic head can be extended. .
[0072]
As described above, according to the device of the present invention, by improving the cleaning effect and maintaining the device for a long time, characteristics assurance regarding recording and reproduction are improved, and reliability is improved.
Therefore, according to the apparatus of the present invention, it is possible to technically facilitate the realization of a small-sized, high-density format of a metal thin-film magnetic recording medium utilizing excellent electromagnetic conversion characteristics as compared with a coating-type magnetic recording medium. Not only that, it can be applied to different formats.
[0073]
[Brief description of the drawings]
FIG. 1 is a schematic layout diagram of an example of a magnetic recording / reproducing apparatus according to the present invention.
FIG. 2 is a schematic side view of an example of a magnetic head cleaning mechanism of an example of a magnetic recording / reproducing apparatus according to the present invention.
FIG. 3 is a schematic layout diagram showing an example of a magnetic head cleaning mechanism in a cleaning state of an example of a magnetic recording / reproducing apparatus according to the present invention.
FIG. 4 is a configuration diagram of a system for measuring output attenuation.
FIG. 5 is a diagram showing measurement results of the number of tape windings and output attenuation in long-time shuttle durability.
FIG. 6 is a schematic layout diagram of another example of the magnetic recording / reproducing apparatus according to the present invention.
FIG. 7 is a diagram illustrating a main part of an example of a cleaning mechanism of the apparatus of the present invention.
FIG. 8 is a diagram showing a relationship between sliding contact and separation from a magnetic recording medium as an example of a cleaning mechanism of the apparatus of the present invention.
FIG. 9 is a flowchart of a dropout measurement for evaluating a cleaning mechanism of the apparatus of the present invention.
FIG. 10 is a configuration diagram of a system for dropout measurement.
FIG. 11A is a diagram showing a relationship between a dropout measurement and a traveling time according to the embodiment of the present invention. B is a diagram showing the relationship between the embodiment of the present invention and the comparative dropout measurement and traveling time.
FIG. 12 is a diagram illustrating a relationship between a dropout measurement and a traveling time according to a reference example.
FIG. 13 is a schematic layout diagram of another example of the magnetic recording / reproducing apparatus according to the present invention.
FIGS. 14A and 14B are explanatory views of respective operation states of an example of the cleaning mechanism of the apparatus of the present invention.
FIG. 15 is a schematic layout view of another example of the magnetic recording / reproducing apparatus according to the present invention.
FIGS. 16A and 16B are explanatory views of respective operating states of a cleaning mechanism of still another example of the magnetic recording / reproducing apparatus according to the present invention.
FIGS. 17A and 17B are diagrams showing the relationship between the dropout measurement and the traveling time according to the embodiment of the present invention.
FIG. 18 is a diagram illustrating a relationship between a dropout measurement and a traveling time according to a reference example.
FIG. 19 is an explanatory diagram of a relationship between a cleaning roller and a blade for a magnetic head used for describing the present invention.
FIG. 20 is an explanatory diagram of a relationship between a magnetic recording medium and a scraping blade for explaining the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Magnetic head, 2,120 ... Cleaning mechanism, 3 ... Fixed drum, 4 ... Rotary drum, 5 ... Cleaning roller part, 6 ... Scratching blade part, 7 ... · Tension spring · · · · · · · · · · 8 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ... Blade support part, 14 ... Tape cassette, 15 ... Supply reel, 16 ... Take-up reel, 17 ... Rotating guide, 18 ... Fixed guide, 19 ... Capstan, Reference numeral 20: pinch roller, 61, 62: rotary shaft, 111: VTR, 112: control computer, 113: oscilloscope, 114: DO counter, 115: recorder 121... First scratch Blade unit, 122: second scraping blade unit, 201: VTR, 202: control computer, 203: detection circuit, 204: recorder, 331, 332 blade support unit, B: Scratching blade, Bf: Front blade surface, Bb: Rear blade surface, M: Magnetic recording medium, fm: Surface on magnetic layer side, fb: Back surface , B1a and B1b, B2a and B2b ... blade

Claims (9)

Equipped with a sliding powder cleaning mechanism,
The cleaning mechanism has a cleaning roller that comes into contact with and separates from the magnetic head, and a scraping blade portion,
In the scraping blade portion, a ridgeline of a blade edge extends along an axial direction of the cleaning roller peripheral surface, and the blade edge can slide along the peripheral surface of the cleaning roller by rotation of the cleaning roller. A magnetic recording / reproducing apparatus comprising a scraping blade. The scraping blade is in a state of sliding contact with the cleaning roller, and a front side of the scraping blade with respect to a tangent of the cleaning roller peripheral surface in a sliding contact portion of the tip of the scraping blade with respect to a rotation direction of the cleaning roller. The magnetic recording / reproducing apparatus according to claim 1, wherein an elevation angle of the blade surface is selected in a range of 30 ° to 60 °. Equipped with a sliding powder cleaning mechanism,
The cleaning mechanism includes first repelling blades each having a repelling blade on the front side and the rear side of the magnetic head with respect to the forward transition direction during recording or / and reproduction during the transition of the magnetic recording medium to the magnetic head. A blade portion and a second scraping blade portion are arranged,
The first scraping blade portion has a blade that is in sliding contact with the magnetic layer side of the magnetic recording medium at least in a forward transition of the magnetic recording medium,
The magnetic recording / reproducing apparatus according to claim 2, wherein the second scraping blade section includes a blade that slides on a back side of the magnetic recording medium at least in a reverse direction of the magnetic recording medium. 4. The structure according to claim 3, wherein each of the scraping blades is rotatably supported, and the blades of the blades slide and separate from the magnetic recording medium by the rotation thereof. Magnetic recording and reproducing device. Each of the scraping blade portions is rotatably supported, and the rotation of each of the scraping blade portions causes the tilt of the magnetic recording medium with respect to the surface on the magnetic layer side and the surface on the back surface side according to the transition direction of the magnetic recording medium. 4. The magnetic recording / reproducing apparatus according to claim 3, wherein: is changed. The first and second scraping blade portions are rotatably supported and include a plurality of blades, and the plurality of blades are alternately rotated by the rotation of each of the scraping blade portions to the surface on the magnetic layer side and the back surface side. 4. The magnetic recording / reproducing apparatus according to claim 3, wherein the inclination with respect to the surface is changed. In each of the scraping blades, in a state of sliding contact with the magnetic recording medium, the elevation angle of the front blade surface with respect to the magnetic recording medium surface in the transition direction of the magnetic recording medium is in a range of 15 ° to 75 °. 7. The magnetic recording / reproducing apparatus according to claim 3, which is selected. Equipped with a sliding powder cleaning mechanism,
The cleaning mechanism further includes a scraping blade portion disposed in front of the magnetic head with respect to a forward transition direction at the time of recording or / and reproduction during the transition of the magnetic recording medium to the magnetic head,
The repelling blade portion includes a plurality of repelling blades supported by a movable blade supporting portion, and is selected by selecting a movable position of the blade supporting portion in each of a forward transition and a reverse transition of the magnetic recording medium. Wherein the scraping blade slides on the magnetic layer side of the magnetic recording medium at a required elevation angle. In each of the scraping blades, in a state of sliding contact with the magnetic recording medium, the elevation angle of the front blade surface with respect to the magnetic recording medium surface in the transition direction of the magnetic recording medium is in a range of 15 ° to 75 °. 9. The magnetic recording / reproducing apparatus according to claim 8, wherein the apparatus is selected.

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