JP2004306442A

JP2004306442A - Printing plate cylinder and stencil printing apparatus

Info

Publication number: JP2004306442A
Application number: JP2003103555A
Authority: JP
Inventors: Mitsuo Sato; 光雄佐藤
Original assignee: Tohoku Ricoh Co Ltd
Current assignee: Tohoku Ricoh Co Ltd
Priority date: 2003-04-08
Filing date: 2003-04-08
Publication date: 2004-11-04
Anticipated expiration: 2023-04-08
Also published as: JP4859010B2

Abstract

<P>PROBLEM TO BE SOLVED: To decrease a noise caused by printing pressure and to reduce the outer diameter dimension of a printing plate cylinder drum by taking a fundamental countermeasure to reduce the thickness of a mechanism for hooking the apex of an original paper sheet to the utmost. <P>SOLUTION: By providing a printing plate cylinder 4 provided with a hooking mechanism 46 for the apex of the original paper sheet which has a pressure-sensitive adhesive layer 45 for freely removably hooking the apex part of the original paper sheet 10a of a stencil plate having been already made into a printing plate, on the surface, it becomes unnecessary to provide a pair of plate materials such as a combination of a clamp plate and a clamp base, so that the mechanism can be constituted into an extremely thin structure. Therefore, even when a swinging contacting and separating action of a pressing body is received for providing a strong printing pressure, as a distance of change in its swinging is extremely small, the noise at collision can be remarkably decreased. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、製版済み孔版原紙が巻き付けられて孔版印刷に供される版胴及びこの版胴を備える孔版印刷装置に関する。
【０００２】
【従来の技術】
原稿画像を光学的に読み取ってデジタル画像信号に変換するスキャナ装置と、そのデジタル画像信号に基づいて感熱孔版原紙にデジタル穿孔製版することが可能な製版装置と、製版済み孔版原紙をその外周面に巻き付けて内部にはインキ供給装置を有する印刷ドラム（版胴）と、印刷用紙を１枚ずつに分離して印刷部へ向けて順次搬送する用紙給紙装置と、搬送された印刷用紙を印刷ドラムに押し当てて印刷画像を形成する印圧装置と、印刷された用紙を印刷ドラムから剥離して排紙トレイに排出積載する排紙装置とを有する孔版印刷装置は既によく知られている。
【０００３】
このような印刷ドラム（版胴）においては、その外周面に製版済み孔版原紙を巻き付け装着されて回転駆動されるが、孔版原紙の先端部を正確かつ確実かつ強固に印刷ドラム外周面の一部に係止するための手段として「原紙先端クランプ装置」が広く採用されている。
【０００４】
従来から採用されている原紙先端クランプ装置は、その殆どの場合が、ドラム軸線方向に平行な軸線回りに開閉回動自在な金属薄板からなるクランプ板と、その金属薄板と磁力で密着しあうように設けられた磁性材料によるクランプベースとの組合せとして構成されている。そして、これらのクランプ板とクランプベースとの間に孔版原紙の先端部を導いて挟み付け、磁力による吸引力と摩擦力とを利用してクランプするようにしている（例えば、特許文献１，２参照）。
【０００５】
その概要について図１１を参照して説明する。従来の印刷ドラム構造は、図１１に示すように、円筒ドラム形状の版胴１００の内周面にインキを供給するインキ供給ローラ１０１が固定的に設けられているため、原紙先端クランプ装置１０２は必然的に版胴１００の外周面側に設けざるを得ないものとなっている。ところが、クランプ板１０３とクランプベース１０４とからなる従来の原紙先端クランプ装置１０２は、その構造上、必要な厚さ寸法が８〜１０ｍｍも要するものとなっている。これは、強力なクランプのためにマグネット板の厚さが必要だったりして、マグネット及びマグネット装着基板の厚さやクランプ板１０３の厚さが加算されて、結果的に、これ程の厚さとなっているものである。
【０００６】
そして、印刷用紙１０５を版胴１００の外周面（製版済み孔版原紙１０６）に押し付けるために設けられている印圧手段としての加圧ローラ１０７は、版胴１００の回転に同期して印圧オン・オフ動作をするように接離制御される。即ち、前述の如く８〜１０ｍｍ厚さの原紙先端クランプ装置１０２を乗り越えるような揺動接離動作を、版胴１００の１回転毎に行うようにしているものである。
【０００７】
ここに、高速回転する版胴１００に対して加圧ローラ１０７が強力な印圧を付与すべく揺動接離動作をするので、加圧ローラ１０７が版胴１００の外周面に衝突する時の“ドンドン”といった大きな騒音が発生してしまうことが以前より問題となっている。
【０００８】
このような問題に対する対応策として、
（１）加圧ローラを軽量化して版胴に対する衝突エネルギーを小さくする方法
（２）加圧ローラの接離揺動動作を滑らかにして（カム曲線をなだらかにする）、版胴に対する衝突エネルギーを小さくする方法
（３）版胴の１回転に１回転してその凹部をクランプ部に対応させるようにした凹部を有する印圧胴を用いる方法
等が提案されている。
【０００９】
【特許文献１】
特開昭５９−９６９８３号公報
【特許文献２】
実開昭６１−３１８３０号公報
【００１０】
【発明が解決しようとする課題】
ところが、（１）の方法では、ゴムの弾性を確保するために必要な厚さがあり、また、強力な印圧で変形しにくい強度が求められること、等から、軽量化にも限度がある。また、少しぐらい軽くしても騒音低下の効果が小さいという本質的な問題もある。
【００１１】
（２）の方法では、加圧ローラの接離揺動動作を滑らかにすれば、必然的に原紙先端クランプ位置から印圧オン位置までの距離が長くなってしまい、必要な印刷画像長さを確保するために版胴のドラム外径が大きくなったり、原紙先端部の余白長さが長くなったりしてしまい、原紙に無駄遣いが生じてしまう等の問題がある。図１２は版胴１００の外周面を水平に展開してこの様子を模式的に示す説明図であり、加圧ローラ１０７の通常の接離揺動動作を示す曲線（ａ）に対して曲線（ｂ）は接離揺動動作を滑らかにした場合の様子を示しており、原紙先端余白長さが通常の寸法ＬａからＬｂに長くなっているのが判る（図１２中、１０８は版胴１００の外周面上に接着されたメッシュスクリーン、１０９は版胴１００において実際に印刷に利用される開孔部分を示している）。
【００１２】
（３）の方法によれば、原紙先端クランプ装置の厚さに関係なく、印圧胴の接離揺動距離をぎりぎりまで小さくすることが可能となり、結果として、印圧騒音低減の効果は大きいといえる。しかし、版胴と同径の印圧胴を用いる必要があり、孔版印刷装置自体が大型化してしまい、印圧胴のコストに加えて、その駆動系のコストも必要となり、全体としてかなり高価になってしまう不具合がある。
【００１３】
結局、従来にあっては、原紙先端を係止するための機構そのものを薄くすることで印圧騒音を低減させるという根本的な提案例はないものである。
【００１４】
本発明の目的は、原紙先端を係止するための機構そのものを極力薄くできる根本的な対応策により、印圧騒音の低減化、版胴ドラム外径寸法の小型化等を図れるようにすることである。
【００１５】
本発明の目的は、加えて、簡単かつ低コストにて上記目的を実現することである。
【００１６】
本発明の目的は、加えて、孔版原紙の先端部の係止処理を確実に行えるようにすることである。
【００１７】
本発明の目的は、加えて、先端部が係止された孔版原紙の剥離時の破損や、剥離後の係止能力の低下を防止できるようにすることである。
【００１８】
本発明の目的は、加えて、孔版原紙の係止性能の確保と剥離排版処理の容易化とを両立できるようにすることである。
【００１９】
本発明の目的は、加えて、係止能力を長期に亘って維持できるようにすることである。
【００２０】
【課題を解決するための手段】
請求項１記載の発明の版胴は、ドラム外周の一部に、製版済み孔版原紙の先端部を係脱自在に係止する粘着剤層を表面に有する原紙先端係止機構を備える。
【００２１】
従って、製版済み孔版原紙の先端部を係脱自在に係止する粘着剤層を表面に有する原紙先端係止機構を備えることにより、クランプ板とクランプベースとの組合せのように対となる板材を設けることなく表面の粘着剤層に製版済み孔版原紙を係止させるだけでよいので、極めて薄型に構成することができ、強力な印圧を付与するために印胴等の押圧体の揺動接離動作を受けてもその揺動変化の距離が非常に小さくて済むため、衝突時の騒音を大幅に低減させることができる。同時に、原紙先端係止機構の前後に設ける印圧を付与できない無駄な寸法部分も小さくできるので、当該版胴のドラム外径寸法を小さくすることもでき、孔版印刷装置の小型化に効果的となる。
【００２２】
請求項２記載の発明は、請求項１記載の版胴において、前記原紙先端係止機構は、ドラム外周面上にそのドラム軸線方向に沿って配設された金属薄板と、この金属薄板の表面上に設けられた前記粘着剤層と、よりなる。
【００２３】
従って、表面に粘着剤層を設けた金属薄板をドラム外周面上にそのドラム軸線方向に沿って配設するだけで、請求項１記載の発明を容易に実現できる。
【００２４】
請求項３記載の発明は、請求項１記載の版胴において、前記原紙先端係止機構は、多孔質円筒状ドラムの非開孔部の外周面上でドラム軸線方向に沿って設けられた前記粘着剤層よりなる。
【００２５】
従って、多孔質円筒状ドラムの非開孔部の外周面上でドラム軸線方向に沿って粘着剤層を直接設けるだけで、請求項１記載の発明を容易に実現できる上に、原紙先端係止機構のより一層の薄型化を図ることができる。
【００２６】
請求項４記載の発明は、請求項１ないし３の何れか一記載の版胴において、前記粘着剤層は、基材を有する両面粘着テープよりなる。
【００２７】
従って、粘着剤層として基材を有する両面粘着テープを利用することにより、金属薄板や版胴外周面上に貼り付ければよく、極めて簡単かつ低コストな構造により請求項１ないし３の何れか一記載の発明を実現できる。
【００２８】
請求項５記載の発明は、請求項１ないし４の何れか一記載の版胴において、前記粘着剤層が係止する前記孔版原紙は、多孔質支持体に合成樹脂繊維１００％の和紙ベースを用いてなり、その多孔質支持体側を前記粘着剤層に貼り付けることにより係止される。
【００２９】
従って、孔版原紙としてその多孔質支持体に合成樹脂繊維１００％の和紙ベースを用い、その多孔質支持体側を粘着剤層に貼り付けるようにしたので、熱可塑性樹脂フィルム部が当該孔版原紙の剥離時に簡単に破れて粘着剤層側に残ってしまう、という問題の発生を防止することができる。また、和紙ベースを構成する主として天然繊維の微小繊維の一部が表面の粘着剤層側に残ってしまい、粘着剤層の粘着力が低下し原紙先端係止機構としての係止性能が低下してしまう不具合も回避することができる。
【００３０】
請求項６記載の発明は、請求項２，４又は５記載の版胴において、前記金属薄板をドラム軸線に平行な軸線回りに開閉回動自在かつ当該ドラム円周方向に往復移動自在に支持する変位支持機構を有する。
【００３１】
従って、金属薄板と粘着剤層との組合せによる原紙先端係止機構に関して、金属薄板を変位支持機構によりドラム軸線に平行な軸線回りに開閉回動自在かつ当該ドラム円周方向に往復移動自在に支持することにより、金属薄板の開閉回動動作及びドラム円周方向の往復移動動作により、係止した孔版原紙の先端部を原紙先端係止機構の粘着剤層から剥離させることができ、よって、剥離排版工程に際して版胴を逆回転させることなく孔版原紙の先端部側から剥離させることができる。
【００３２】
請求項７記載の発明の孔版印刷装置は、請求項１ないし６の何れか一記載の版胴と、製版済み孔版原紙の供給を受けて当該製版済み孔版原紙の先端部を前記版胴上の原紙先端係止機構における粘着剤層上に押し当てる揺動自在な原紙先端押し当て部材と、この原紙先端押し当て部材を押し当て方向に駆動する駆動源と、前記版胴のドラム外周面に巻き付けられた製版済み孔版原紙を印刷用紙に押し付ける押圧体と、前記版胴内に設けられて当該版胴の内周面にインキを供給するインキ供給機構と、を備える。
【００３３】
従って、製版済み孔版原紙の供給を受けて当該製版済み孔版原紙の先端部を版胴上の原紙先端係止機構における粘着剤層上に押し当てる揺動自在な原紙先端押し当て部材を備えるので、当該製版済み孔版原紙の先端部を粘着剤層に確実に係止させることができる。
【００３４】
請求項８記載の発明の孔版印刷装置は、請求項１ないし５の何れか一記載の版胴と、製版済み孔版原紙の供給を受けて当該製版済み孔版原紙の先端部を前記版胴上の原紙先端係止機構における粘着剤層上に押し当てる揺動自在な原紙先端押し当て部材と、この原紙先端押し当て部材を押し当て方向に駆動する駆動源と、前記版胴のドラム外周面に巻き付けられた製版済み孔版原紙を印刷用紙に押し付ける押圧体と、前記版胴内に設けられて当該版胴の内周面にインキを供給するインキ供給機構と、前記版胴のドラム外周面に巻き付けられた製版済み孔版原紙を排版時には当該版胴の回転方向後端部側から順に剥離し当該製版済み孔版原紙の先端部を前記粘着剤層表面から引き剥がす方向に剥離する剥離排版装置と、を備える。
【００３５】
従って、版胴のドラム外周面に巻き付けられた製版済み孔版原紙を排版時には当該版胴の回転方向後端部側から順に剥離し当該製版済み孔版原紙の先端部を粘着剤層表面から引き剥がす方向に剥離する剥離排版装置を備えるので、製版済み孔版原紙を排版時には当該版胴の回転方向後端部側から順に剥離し最終的に製版済み孔版原紙の先端部を粘着剤層表面から引き剥がす方向に剥離させることで、強力な層方向粘着力を確保しつつ簡単な機構で小さい力で排版時の剥離動作を行わせることができる。
【００３６】
請求項９記載の発明の孔版印刷装置は、請求項６記載の版胴と、製版済み孔版原紙の供給を受けて当該製版済み孔版原紙の先端部を前記版胴上の原紙先端係止機構における粘着剤層上に押し当てる揺動自在な原紙先端押し当て部材と、この原紙先端押し当て部材を押し当て方向に駆動する駆動源と、前記版胴のドラム外周面に巻き付けられた製版済み孔版原紙を印刷用紙に押し付ける押圧体と、前記版胴内に設けられて当該版胴の内周面にインキを供給するインキ供給機構と、前記版胴のドラム外周面に巻き付けられた製版済み孔版原紙を排版時には前記変位支持機構により前記金属薄板をドラム外周面から開放回動させるとともに前記版胴の回転に伴いドラム円周方向に移動変位させて当該版胴の回転方向先端部側から順に剥離する剥離排版装置と、を備える。
【００３７】
従って、版胴として請求項６記載の版胴を用いているので、金属薄板の開閉回動動作及びドラム円周方向の往復移動動作により、係止した孔版原紙の先端部を原紙先端係止機構の粘着剤層から剥離させることができ、よって、剥離排版工程に際して版胴を逆回転させることなく孔版原紙の先端部側から剥離させることができる。
【００３８】
請求項１０記載の発明は、請求項８又は９記載の孔版印刷装置において、製版済み孔版原紙の剥離排版処理を、その直後に次の新規な製版済み孔版原紙の給版処理が行われることを条件に実行させる剥離排版処理制御手段を備える。
【００３９】
従って、製版済み孔版原紙の剥離排版処理を、その直後に次の新規な製版済み孔版原紙の給版処理が行われることを条件に実行させることにより、表面に位置する粘着剤層を常に孔版原紙の先端部によって覆うことができ、よって、粘着剤層が露出することにより装置内の紙粉や空気中のほこり等が付着して粘着力が低下してしまう不具合を回避し、係止性能を長期に亘って維持させることができる。
【００４０】
【発明の実施の形態】
本発明の第一の実施の形態を図１ないし図８に基づいて説明する。本実施の形態は、デジタル感熱式の孔版印刷装置への適用例を示す。
【００４１】
図１は、当該孔版印刷装置の全体の内部構造を概略的に示す縦断正面図である。当該孔版印刷装置は、デジタル複写機機能を併有する構成とされており、原稿画像を読み取るスキャナ１を備えている。このスキャナ１は上面に開閉自在な圧板２を備えるとともに、複数枚の原稿を１枚ずつ順次自動的に給紙搬送するためのＡＤＦ３を備えている。もっとも、パソコン等から送信される画像データに基づいて製版する場合には、スキャナ１は必須ではなく、当該孔版印刷装置を印刷機機能のみ有する構成としてもよい。
【００４２】
当該孔版印刷装置の本体内においては、時計方向に回転駆動される版胴４が設けられている。必要な印刷画像長さが確保された版胴４の周囲には、製版装置５、給紙装置６、印圧装置７、剥離排版装置８が設けられている。また、版胴４の内部にはインキ供給機構９が設けられている。
【００４３】
製版装置５は、スキャナ１で読み取った画像データ又は外部から入力される画像データに応じて孔版原紙１０を加熱溶融穿孔することによりマスタを製版する装置であり、ロール状に巻回された孔版原紙１０を保持する保持軸１１、多数の発熱素子を備えて孔版原紙１０を加熱溶融穿孔するサーマルヘッド１２、ステッピングモータ等により回転駆動されて孔版原紙１０をサーマルヘッド１２に押し付けるプラテンローラ１３、サーマルヘッド１２により加熱溶融穿孔された孔版原紙１０を所定長さに切断するカッタ１４等により構成されている。サーマルヘッド１２により加熱溶融穿孔された孔版原紙１０をカッタ１４により所定長さに切断することにより、製版済み孔版原紙１０ａが作成され（製版終了）、この製版済み孔版原紙１０ａは後述するように版胴４の外周面上に巻き付けられる。
【００４４】
給紙装置６は、給紙台１５上に積載された印刷用紙１６をその最上位紙から１枚ずつ順に給紙する給紙コロ１７、搬送ローラ１８、印刷部への印刷タイミングを取るレジストローラ１９等により構成されている。なお、２０は用紙サイズ検知センサである。
【００４５】
印圧装置７は、版胴４の外周面（より詳しくは、版胴４の外周面に巻き付けられた製版済み孔版原紙１０ａ）に接離自在で、印刷用紙１６を製版済み孔版原紙１０ａに押し付ける押圧体としてのプレスローラ２１と、このプレスローラ２１の接離動作を行うための変位機構２２とにより構成されている。
【００４６】
剥離排版装置８は、版胴４の近傍に配設された一対のローラ２３，２４と、排版ボックス２５とよりなる。ここに、一方のローラ２３は版胴４に接離自在であり、剥離排版時には当該版胴４の外周面に接してその接触面で逆方向となる向きに回転されることにより版胴４上の製版済み孔版原紙１０ａの剥離動作を行うように構成されている。
【００４７】
また、印圧装置７よも搬送方向下流側には、印刷済みの印刷用紙１６を排紙台２６上に搬送排紙する搬送装置２７が設けられている。２８はサイドフェンス、２９はエンドフェンスである。
【００４８】
インキ供給機構９は、版胴４を回転自在に保持する保持軸を兼ねたインキパイプ３０、版胴４の内周面との間に微小間隔をもって配置されるとともに版胴４と同じ方向に回転駆動されるインキローラ３１、インキローラ３１との間に微小間隔をもって配置されたドクターローラ３２、これらのローラ３１，３２間に挟まれて形成された断面形状が略楔形状のインキ溜り部３３等により構成されている。これにより、インキポンプ（図示せず）の駆動によりインキパイプ３０内を通ってインキが供給され、そのインキがインキパイプ３０に形成されている複数個のインキ孔３０ａから流出してインキ溜り部３３内に溜り、インキ溜り部３３内にたまったインキがインキローラ３１の回転により版胴４の内周面に供給され、そのインキが製版済み孔版原紙１０ａの穿孔部分から滲み出して印刷用紙１６に転移することにより印刷が行われる。
【００４９】
次いで、版胴４の構造例について説明する。図２は版胴４の一部を拡大して示す縦断正面図、図３はその一部をさらに拡大して示す縦断正面図である。基本的に多数の開孔４１を有して多孔質金属製の円筒ドラム状に形成された版胴４は、その外周面上に端部を接着部４２で接着させたメッシュスクリーン４３が設けられ、版胴開孔エリアを覆っている。このような版胴４において、当該多孔質円筒ドラムの非開孔部４４表面上に位置させて、そのドラム軸心方向に沿って粘着剤層４５が直接外部に露出する形で設けられて原紙先端係止機構４６が構成されている。
【００５０】
ここで、粘着剤層４５には、図３に示すような両面粘着テープが利用されている。即ち、基材としてのＰＥＴフィルム４７に対してその表面側粘着剤４８と裏面側粘着剤４９とを有するテープ構造であり、裏面側粘着剤４９を非開孔部４４上に貼り付けることにより固定されている。一方、このような粘着剤層４５により先端部が係止される孔版原紙１０は、図３に示すように、熱可塑性樹脂フィルム５０と多孔質の和紙ベース５１とを接着貼り合せた構造のものであり、和紙ベース５１側が表面側粘着剤４８に貼り付けられるように設定されている。
【００５１】
また、このような表面側粘着剤４８を有する版胴４に対して、製版装置５との間には、図４に示すように、製版済み孔版原紙１０ａの供給を受けて当該製版済み孔版原紙１０ａの先端部を版胴４上の粘着剤層４５上に押し当てる支軸５２を中心に揺動自在な原紙先端押し当て部材としての押し付けアーム５３と、この押し付けアーム５３の一部に連結されて当該押し付けアーム５３を押し当て方向に駆動する駆動源としてのソレノイド５４と、この押し付けアーム５３の一部に連結されて当該押し付けアーム５３を押し当て方向から離反する方向に付勢するばね５５と、が設けられている。押し付けアーム５３の押し付け部分には密着性を確実にするための発泡ゴム等による弾性体５６が設けられている。５７，５８は製版装置５の出口部に配置されたローラである。また、粘着剤層４５（版胴４）と押し付けアーム５３との間に向けて搬送される製版済み孔版原紙１０ａの先端側を押し付けアーム５３に向けて案内するような気流を吹き込む送風ファン５９が設けられている。
【００５２】
このような構成において、製版装置５で製版された製版済み孔版原紙１０ａは版胴４上の粘着剤層４５の位置と同期をとるようにして、図４に示す如く、版胴４・押し付けアーム５３間に給紙搬送される。この時、送風ファン５９による吹き付け気流が製版済み孔版原紙１０ａの先端部に対して吹き付けられているので、当該製版済み孔版原紙１０ａの先端部は粘着剤層４５に貼り付くことなく所定量送り出されて停止する。そして、所定タイミングでソレノイド５４をオンさせることにより、押し付けアーム５３が支軸５２を中心に揺動し、製版済み孔版原紙１０ａの先端部を粘着剤層４５上に押し付け密着させる。これにより、製版済み孔版原紙１０ａの先端部は粘着剤層４５に貼り付いて係止されることとなる。この際、押し付け部分には弾性体５６が介在されているので、製版済み孔版原紙１０ａの先端部の粘着剤層４５に対する密着性はより確実なものとなる。その後、版胴４が時計方向に若干回動した後、ソレノイド５４をオフさせ、押し付けアーム５３をばね５５による付勢力で版胴４から離反解除させ、版胴４の回動を継続させることにより、先端部以降の製版済み孔版原紙１０ａは版胴４の外周面上に存在するインキによってメッシュスクリーン４３上に巻き付け密着されることとなる。
【００５３】
このようにして、製版済み孔版原紙１０ａの先端部は図２に示すように版胴４の外周面上に対して粘着剤層４５によって係脱自在に係止されることとなる。この場合、原紙先端係止機構４６は単に粘着剤層４５により構成されているので、従来のクランプ板とクランプベースとの組合せのように対となる板材を設ける必要がなく、極めて薄型に構成することができる。よって、強力な印圧を付与するためにプレスローラ２１の揺動接離動作を受けてもその揺動変化の距離が非常に小さくて済むため、衝突時の騒音を大幅に低減させることができる。同時に、原紙先端係止機構４６の前後に設ける印圧を付与できない無駄な寸法部分も小さくできるので、当該版胴４のドラム外径寸法を小さくすることもでき、孔版印刷装置の小型化に効果的となる。
【００５４】
ところで、粘着剤層４５による製版済み孔版原紙１０ａの先端部の係止状態について考察する。本実施の形態では、前述したように、熱可塑性樹脂フィルム５０と多孔質の和紙ベース５１とを接着貼り合せた構造の製版済み孔版原紙１０ａを、和紙ベース５１側が粘着剤層４５に貼り付けられるように設定されている。ここに、裏面側粘着剤４９側は一度貼り付ければ剥がすことはまれであるが、表面側粘着剤４８側は繰返し新しい製版済み孔版原紙１０ａが貼り付けられては剥がされるという処理が行われる。ここに、万一、熱可塑性樹脂フィルム５０側を粘着剤層４５に貼り付ける構造とした場合、当該熱可塑性樹脂フィルム５０は厚さが１〜２μｍ程度と非常に薄いため、剥離時に簡単に破れてしまう問題がある。この点、本実施の形態では、上述のように和紙ベース５１側を粘着剤層４５に貼り付けるようにしているので、このような不具合を解消できる。
【００５５】
また、孔版原紙１０の多孔質の和紙ベースとしては、通常、その材質として天然和紙に合成繊維を若干混抄したものが用いられる。しかし、このような材質の場合、剥離排版過程で表面側粘着剤４８側から孔版原紙１０ａを剥離した場合、多孔質の和紙ベースを構成する主として天然繊維の微小繊維の一部が表面側粘着剤４８側に残ってしまう、という不具合が発生する。このような現象が何度も繰り返され蓄積されていくと、表面側粘着剤４８の粘着力が低下し原紙先端係止機構４６としての係止性能が低下してしまう。
【００５６】
この点、本実施の形態では、孔版原紙１０の多孔質の和紙ベース５１に関しても、合成繊維１００％で天然繊維を含まないものを用いているので、微小繊維の一部が表面側粘着剤４８側に残ってしまう、という不具合は発生しにくくなる。これは、合成繊維の場合、その太さが均一で局部的な分離が起こりにくいためである。
【００５７】
ところで、本実施の形態のような粘着剤層４５を利用した原紙先端係止機構４６によれば、図５に示すように、粘着剤層４５の表面に対して製版済み孔版原紙１０をその層方向（平面方向）であれば非常に強い力Ｐ１で引いても強い粘着力によって強力な保持能力を発揮できる一方、粘着剤層４５の表面に対してほぼ垂直方向に引いた場合には、比較的弱い力Ｐ２であっても簡単に剥離してしまう、という特徴を有する。
【００５８】
具体例として、例えば、粘着剤層４５（両面粘着テープ）として幅１５ｍｍ、長さ３００ｍｍの住友３Ｍ社のスコッチ両面粘着テープＳＴ４１６を用い、孔版原紙１０としてプリポートマスターｍ−８０を用いた簡単な実験結果では、水平方向の引っ張り力Ｐ１は１０ｋｇｆ以上（孔版原紙１０自身が破れてしまいそうな力）であるが、垂直方向の引っ張り力Ｐ２はせいぜい２００ｇｆ程度であることが判明したものである。
【００５９】
よって、本実施の形態の場合、このような特徴を利用することにより、剥離排版処理工程も簡単に実現できる。このような特徴を活かした剥離排版処理について図６を参照して説明する。版胴４の外周面上にインキによって粘着巻き付けされている孔版原紙１０ａは、その先端部係止側とは反対の後端部にはインキが付着していない余白部分１０ｂを有するので、版胴４を逆方向（反時計方向）に回転させるとともに図６（ａ）に示すように版胴４に接してその接触部分で逆方向となる向きにローラ２３を回転駆動させることにより、孔版原紙１０ａは後端部１０ｂ側から順に剥離され、かつ、版胴４の反時計方向の回転及びローラ２３，２４の回転によりその剥離・搬送が進む。そして、最終的に粘着剤層４５部分まで至ると、図６（ｂ）に示すように、粘着剤層４５に対して垂直方向に孔版原紙１０ａを引き剥がそうとする剥離動作となり、弱い力で先端部の剥離を行うことができる。
【００６０】
ところで、本実施の形態の孔版印刷装置の制御系の概略構成例を図７に示す。この制御系は、ＣＰＵ、ＲＯＭ及びＲＡＭを備えるコンピュータ構成の制御部６１を主要な構成要素として備え、この制御部６１に製版装置５、給紙装置６、版胴４やプレスローラ２１等による印刷部６２、剥離排版装置８、操作パネル６３等が接続されている。
【００６１】
このような制御部６１により実行される本実施の形態の剥離排版処理の制御例を図８に示す概略フローチャートを参照して説明する。まず、操作パネル６３等を通じてスタートキーが押下されると（Ｓ１のＹ）、前回の印刷処理において版胴４の外周面上に巻き付けられている孔版原紙１０ａの剥離排版処理が実行される（Ｓ２）。次いで、画像データに基づき孔版原紙１０に対する製版処理が実行され（Ｓ３）、製版された製版済み孔版原紙１０ａを版胴４の外周面上に巻き付ける給版巻き付け処理を実行する（Ｓ４）。即ち、先端部を粘着剤層４５上に押し付けて係止させるとともに版胴４の回転に伴い先端部以降を外周面上に巻き付ける。そして、版胴４及びプレスローラ２１を回転させながら印刷用紙１６を給紙させるとともにインキを供給し、印刷用紙１６上に印刷を行う（Ｓ５）。所定枚数の印刷が終了すると（Ｓ６のＹ）、今回の印刷動作は終了となるが、次の印刷のためのスタートキーが押下されるまで（Ｓ１のＹ）、待機する状態となる。つまり、今回版胴４の外周面上に巻き付けられた孔版原紙１０ａは次回の印刷のための給版処理が行われるまで、巻き付けられた状態のまま放置されることとなる。このようなステップＳ１〜Ｓ６の一連の処理が剥離排版処理制御手段の機能として実行される。
【００６２】
このように、本実施の形態によれば、製版済み孔版原紙１０ａの剥離排版処理を、その直後に次の新規な製版済み孔版原紙の給版処理が行われることを条件に実行させることにより、表面に位置する粘着剤層４５を常に孔版原紙１０ａの先端部によって覆うことができ、よって、粘着剤層４５が露出することにより装置内の紙粉や空気中のほこり等が付着して粘着力が低下してしまう不具合を回避し、係止性能を長期に亘って維持させることができる。
【００６３】
本発明の第二の実施の形態を図９に基づいて説明する。第一の実施の形態で示した部分と同一部分は同一符号を用いて示し、説明も省略する（以降の実施の形態でも同様とする）。
【００６４】
前述の実施の形態では、版胴４自身の非開孔部４４上に直接両面粘着テープ等の粘着剤層４５を設けることにより原紙先端係止機構４６を構成するようにしたが、本実施の形態では、版胴４の非開孔部４４領域に設けられる金属薄板７１とこの金属薄板７１の表面上に貼り付けられた粘着剤層４５とにより原紙先端係止機構７２を構成したものである。ここに、金属薄板７１はドラム軸線と平行に細長く設けられたもので、その両端は、版胴４のフランジ７３に対してねじ７４により固定されている。粘着剤層４５自身は第一の実施の形態の場合と同様である。
【００６５】
本実施の形態によれば、予め表面に粘着剤層４５が貼り付けられた金属薄板７１を版胴４の非開孔部４４に位置づけて固定すればよく、別部材を要するものの、粘着剤層４５の貼り付け作業を金属薄板７１上で行うことができ、簡単に実現できる。
【００６６】
本発明の第三の実施の形態を図１０に基づいて説明する。本実施の形態では、前述の第二の実施の形態の場合と同様に、金属薄板７１と粘着剤層４５とよりなる原紙先端係止機構７２を構成するが、金属薄板７１をフランジ７３に対して固定的に設けず、変位支持機構７５によりドラム軸線に平行な軸線回りに開閉回動自在かつ当該ドラム円周方向に往復移動自在に支持して設けたものである。即ち、版胴４の両端のフランジ７３外にはドラム中心軸７６回りに矢印Ａ方向に回動変位自在で版胴半径程度の長さを有する支持アーム７７が設けられ、この支持アーム７７の先端寄りに設けられた支軸７８を中心として回動自在なクランパアーム７９により金属薄板７１の両端が支持されている。ここに、支軸７８は孔版原紙１０ａの先端部側から見た場合、金属薄板７１の後端側に位置しており、この支軸７８により金属薄板７１はドラム軸線に平行な軸線回りに開閉回動自在とされている。また、ドラム中心軸７６回りに回動変位自在な支持アーム７７により当該ドラム円周方向に往復移動自在とされている。ここに、支持アーム７７上には図示しない駆動伝達機構により軸８０を中心に回転駆動される歯車８１が設けられ、クランパアーム７９の支軸７８周りにはこの歯車８１に噛み合う部分的な歯車部８２が形成されている。さらに、支持アーム７７を時計方向に付勢するばね８３が設けられているとともに、時計方向の支持アーム７７の移動量を規制するストッパ片８４がフランジ７３上に設けられている。
【００６７】
このような構成において、剥離動作時以外は、金属薄板７１は図１０（ａ）に示すように版胴４の非開孔部４４の外周面上に倒れた閉状態にある。そして、前述したような巻き付け処理により、金属薄板７１上の粘着剤層４５に先端部が貼り付け係止される形で製版済み孔版原紙１０ａが版胴４の外周面に巻きつけられ、印刷動作に供される。
【００６８】
その後、当該製版済み孔版原紙１０ａの剥離排版処理時になると、当該孔版印刷装置における駆動機構（図示せず）によって、軸８０を固定的に保持しながら歯車８１に矢印Ｂ方向（反時計方向）の回転駆動力が与えられる。これにより、クランパアーム７９が図１０（ａ）（ｂ）に示す矢印Ｃ方向（時計方向）に回動変位し、このクランパアーム７９に支持された金属薄板７１も版胴４の外周面から離れて立つような状態に開放変位動作を行う。最終的には、図１０（ｂ）に示すように外周面に対してほぼ直交する状態まで起こされる。この時、孔版原紙１０ａの先端部は金属薄板７１の粘着剤層４５上に貼り付き係止されたままの状態である。
【００６９】
このようにクランパアーム７９が開状態のまま、版胴４が図１０（ｂ）（ｃ）に示すように矢印Ｄ方向（時計方向）に回転駆動される。すると、支持アーム７７に対してストッパ片８３が離れていき、同時に、版胴４の外周面上にインキで密着している孔版原紙１０ａも徐々に離れていくので、最終的には、図１０（ｃ）に示すように、粘着剤層４５部分においても孔版原紙１０ａの先端部が徐々に引き剥がされる形で剥離されていくこととなる。このようにして、金属薄板７１が版胴４の外周面上において開き動作と移動動作とを行うことにより、孔版原紙１０ａの先端部側を容易かつ小さな力で粘着剤層４５から剥離してフリー状態にすることができる。この結果、剥離排版装置８による孔版原紙１０ａの剥離・排版処理を孔版原紙１０ａの後端部側からでなく、先端部側から行うことができる。
【００７０】
【発明の効果】
請求項１記載の発明によれば、製版済み孔版原紙の先端部を係脱自在に係止する粘着剤層を表面に有する原紙先端係止機構を備えるので、クランプ板とクランプベースとの組合せのように対となる板材を設けることなく表面の粘着剤層に製版済み孔版原紙を係止させるだけでよく、極めて薄型に構成することができ、強力な印圧を付与するために印胴等の押圧体の揺動接離動作を受けてもその揺動変化の距離が非常に小さくて済むため、衝突時の騒音を大幅に低減させることができ、同時に、原紙先端係止機構の前後に設ける印圧を付与できない無駄な寸法部分も小さくできるので、当該版胴のドラム外径寸法を小さくすることもでき、孔版印刷装置の小型化に効果的となる。
【００７１】
請求項２記載の発明によれば、原紙先端係止機構はドラム外周面上にそのドラム軸線方向に沿って配設された金属薄板とこの金属薄板の表面上に設けられた粘着剤層とよりなるので、表面に粘着剤層を設けた金属薄板をドラム外周面上にそのドラム軸線方向に沿って配設するだけで、請求項１記載の発明を容易に実現することができる。
【００７２】
請求項３記載の発明によれば、原紙先端係止機構は多孔質円筒状ドラムの非開孔部の外周面上でドラム軸線方向に沿って設けられた粘着剤層よりなるので、多孔質円筒状ドラムの非開孔部の外周面上でドラム軸線方向に沿って粘着剤層を直接設けるだけで、請求項１記載の発明を容易に実現することができる上に、原紙先端係止機構のより一層の薄型化を図ることができる。
【００７３】
請求項４記載の発明によれば、粘着剤層として基材を有する両面粘着テープを利用するようにしたので、金属薄板や版胴外周面上に貼り付ければよく、極めて簡単かつ低コストな構造により請求項１ないし３の何れか一記載の発明を実現することができる。
【００７４】
請求項５記載の発明によれば、請求項１ないし４の何れか一記載の版胴において、孔版原紙としてその多孔質支持体に合成樹脂繊維１００％の和紙ベースを用い、その多孔質支持体側を粘着剤層に貼り付けるようにしたので、熱可塑性樹脂フィルム部が当該孔版原紙の剥離時に簡単に破れて粘着剤層側に残ってしまう、という問題の発生を防止することができ、また、和紙ベースを構成する主として天然繊維の微小繊維の一部が表面の粘着剤層側に残ってしまい、粘着剤層の粘着力が低下し原紙先端係止機構としての係止性能が低下してしまう不具合も回避することができる。
【００７５】
請求項６記載の発明によれば、請求項２，４又は５記載の版胴において、金属薄板と粘着剤層との組合せによる原紙先端係止機構に関して、金属薄板を変位支持機構によりドラム軸線に平行な軸線回りに開閉回動自在かつ当該ドラム円周方向に往復移動自在に支持するようにしたので、金属薄板の開閉回動動作及びドラム円周方向の往復移動動作により、係止した孔版原紙の先端部を原紙先端係止機構の粘着剤層から剥離させることができ、よって、剥離排版工程に際して版胴を逆回転させることなく孔版原紙の先端部側から剥離させることができる。
【００７６】
請求項７記載の発明の孔版印刷装置によれば、製版済み孔版原紙の供給を受けて当該製版済み孔版原紙の先端部を版胴上の原紙先端係止機構における粘着剤層上に押し当てる揺動自在な原紙先端押し当て部材を備えるので、当該製版済み孔版原紙の先端部を粘着剤層に確実に係止させることができる。
【００７７】
請求項８記載の発明の孔版印刷装置によれば、版胴のドラム外周面に巻き付けられた製版済み孔版原紙を排版時には当該版胴の回転方向後端部側から順に剥離し当該製版済み孔版原紙の先端部を粘着剤層表面から引き剥がす方向に剥離する剥離排版装置を備えるので、製版済み孔版原紙を排版時には当該版胴の回転方向後端部側から順に剥離し最終的に製版済み孔版原紙の先端部を粘着剤層表面から引き剥がす方向に剥離させることで、強力な層方向粘着力を確保しつつ簡単な機構で小さい力で排版時の剥離動作を行わせることができる。
【００７８】
請求項９記載の発明の孔版印刷装置によれば、版胴として請求項６記載の版胴を用いているので、金属薄板の開閉回動動作及びドラム円周方向の往復移動動作により、係止した孔版原紙の先端部を原紙先端係止機構の粘着剤層から剥離させることができ、よって、剥離排版工程に際して版胴を逆回転させることなく孔版原紙の先端部側から剥離させることができる。
【００７９】
請求項１０記載の発明によれば、請求項８又は９記載の孔版印刷装置において、製版済み孔版原紙の剥離排版処理を、その直後に次の新規な製版済み孔版原紙の給版処理が行われることを条件に実行させることにより、表面に位置する粘着剤層を常に孔版原紙の先端部によって覆うことができ、よって、粘着剤層が露出することにより装置内の紙粉や空気中のほこり等が付着して粘着力が低下してしまう不具合を回避し、係止性能を長期に亘って維持させることができる。
【図面の簡単な説明】
【図１】本発明の第一の実施の形態の孔版印刷装置の全体の内部構造を概略的に示す縦断正面図である。
【図２】版胴の一部を拡大して示す縦断正面図である。
【図３】その一部をさらに拡大して示す縦断正面図である。
【図４】原紙先端の巻き付け動作を説明するための縦断正面図である。
【図５】粘着剤層の特徴を説明するための縦断正面図である。
【図６】剥離動作を示す縦断正面図である。
【図７】孔版印刷装置の制御系の概略構成例を示すブロック図である。
【図８】剥離排版処理の制御例を示す概略フローチャートである。
【図９】本発明の第二の実施の形態の版胴を示す縦断正面図である。
【図１０】本発明の第三の実施の形態の剥離動作を工程順に示す縦断正面図である。
【図１１】従来の孔版印刷装置の構成例を示す概略正面図である。
【図１２】従来の（２）の方法による欠点を説明するための縦断正面図である。
【符号の説明】
４版胴
８剥離排版装置
９インキ供給機構
１０孔版原紙
１０ａ製版済み孔版原紙
１６印刷用紙
２１押圧体
４４非開孔部
４５粘着剤層
４６原紙先端係止機構
４７基材
５０多孔質支持体
５１和紙ベース
５３押し当て部材
５４駆動源
７１金属薄板
７２原紙先端係止機構
７５変位支持機構[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stencil printing machine provided with a stencil sheet, on which a stencil sheet is wound and provided for stencil printing.
[0002]
[Prior art]
A scanner device that optically reads a document image and converts it into a digital image signal, a plate making device that can make digital perforation on a heat-sensitive stencil based on the digital image signal, A printing drum (plate cylinder) that is wound and has an ink supply device inside, a paper feeding device that separates printing paper one by one and sequentially conveys it to a printing unit, and a printing drum that conveys the printing paper conveyed A stencil printing apparatus having a printing pressure device for forming a print image by pressing the printing paper onto a printing paper and a discharge device for discharging printed paper from a print drum and stacking the discharged paper on a discharge tray are already well known.
[0003]
In such a printing drum (plate cylinder), a perforated stencil sheet is wrapped around the outer peripheral surface thereof and is driven to rotate. However, the leading end of the stencil sheet is accurately, reliably and firmly fixed to a part of the outer peripheral surface of the printing drum. As a means for locking the sheet, a "base paper tip clamping device" is widely used.
[0004]
In most cases, the base paper leading edge clamping device that has been conventionally used is such that the metal plate is magnetically adhered to a clamp plate made of a thin metal plate that can be freely opened and closed about an axis parallel to the drum axis direction. Is configured as a combination with a clamp base made of a magnetic material provided in the above. The leading end of the stencil sheet is guided and sandwiched between the clamp plate and the clamp base, and is clamped by using a suction force and a friction force by a magnetic force (for example, Patent Documents 1 and 2). reference).
[0005]
The outline will be described with reference to FIG. In the conventional printing drum structure, as shown in FIG. 11, an ink supply roller 101 for supplying ink is fixedly provided on the inner peripheral surface of a cylindrical drum-shaped plate cylinder 100. This is inevitably provided on the outer peripheral surface side of the plate cylinder 100. However, the conventional base paper tip clamping apparatus 102 including the clamp plate 103 and the clamp base 104 requires a required thickness dimension of 8 to 10 mm due to its structure. This is because the thickness of the magnet plate is required for strong clamping, and the thickness of the magnet and the magnet mounting board and the thickness of the clamp plate 103 are added, and as a result, the thickness becomes so large. Is what it is.
[0006]
Then, a pressure roller 107 as a printing pressure means provided for pressing the printing paper 105 against the outer peripheral surface of the plate cylinder 100 (plate making stencil sheet 106) turns on the printing pressure in synchronization with the rotation of the plate cylinder 100. -The contact / separation is controlled to perform the off operation. That is, as described above, the swinging contacting / separating operation is performed for each rotation of the plate cylinder 100 so as to get over the stencil sheet leading end clamping device 102 having a thickness of 8 to 10 mm.
[0007]
Here, the pressure roller 107 swings and separates to apply a strong printing pressure to the high-speed rotating plate cylinder 100. Therefore, when the pressure roller 107 collides with the outer peripheral surface of the plate cylinder 100, The generation of loud noises such as "don-don" has become a problem.
[0008]
To address these issues,
(1) A method for reducing the impact energy on the plate cylinder by reducing the weight of the pressure roller
(2) Method of smoothing the contact / separation swing operation of the pressure roller (smoothing the cam curve) to reduce the collision energy with respect to the plate cylinder
(3) A method using a printing pressure cylinder having a concave portion in which the concave portion corresponds to the clamp portion by making one rotation per rotation of the plate cylinder.
Etc. have been proposed.
[0009]
[Patent Document 1]
JP-A-59-96983
[Patent Document 2]
Japanese Utility Model Publication No. 61-31830
[0010]
[Problems to be solved by the invention]
However, in the method (1), there is a thickness necessary to secure the elasticity of the rubber, and a strength that is not easily deformed by a strong printing pressure is required. . There is also an essential problem that the effect of noise reduction is small even if it is slightly lighter.
[0011]
In the method (2), if the pressing and separating operation of the pressing roller is made smooth, the distance from the base paper tip clamping position to the printing pressure ON position is inevitably increased. In order to ensure the above, there is a problem that the outer diameter of the drum of the plate cylinder becomes large, the margin of the leading end of the base paper becomes long, and waste of the base paper occurs. FIG. 12 is an explanatory view schematically showing this state in which the outer peripheral surface of the plate cylinder 100 is developed horizontally, and is a curve (a) showing a normal contact / separation swinging operation of the pressure roller 107. FIG. 12B shows a state in which the contact / separation swinging operation is smoothed, and it can be seen that the length of the margin of the base end of the base paper is increased from the normal dimension La to Lb (in FIG. 12, reference numeral 108 denotes the plate cylinder 100). , A mesh screen adhered on the outer peripheral surface of the plate cylinder 109 indicates an opening portion actually used for printing in the plate cylinder 100).
[0012]
According to the method (3), the contact / separation swing distance of the printing pressure cylinder can be reduced to a minimum irrespective of the thickness of the base paper tip clamping device, and as a result, the effect of reducing the printing pressure noise is large. It can be said that. However, it is necessary to use a printing cylinder having the same diameter as the printing cylinder, which increases the size of the stencil printing machine itself. There is a problem that it becomes.
[0013]
As a result, there has been no fundamental proposal for reducing the printing pressure noise by thinning the mechanism itself for locking the leading end of the base paper.
[0014]
SUMMARY OF THE INVENTION It is an object of the present invention to reduce the printing pressure noise and to reduce the outer diameter of the plate drum, etc. by a fundamental countermeasure capable of making the mechanism for locking the leading end of the base paper as thin as possible. It is.
[0015]
It is an additional object of the present invention to achieve the above objects simply and at low cost.
[0016]
Another object of the present invention is to ensure that the leading end of the stencil sheet can be locked.
[0017]
Another object of the present invention is to prevent breakage of the stencil sheet whose leading end portion is locked when the stencil sheet is peeled off and decrease in the locking ability after peeling.
[0018]
Another object of the present invention is to make it possible to ensure both the locking performance of the stencil sheet and the ease of the peeling and discharging process.
[0019]
It is an additional object of the invention to enable the locking capability to be maintained over a long period of time.
[0020]
[Means for Solving the Problems]
The plate cylinder according to the first aspect of the present invention is provided with a stencil tip locking mechanism having a pressure-sensitive adhesive layer on the surface of a part of the outer periphery of the drum, the stencil stencil being releasably locked.
[0021]
Therefore, by providing a stencil tip locking mechanism having a pressure-sensitive adhesive layer on its surface for releasably locking the leading end of the stencil sheet, a pair of plate materials such as a combination of a clamp plate and a clamp base can be provided. Since it is only necessary to lock the stencil sheet made on the surface of the pressure-sensitive adhesive layer without providing it, it can be made extremely thin, and the pressing body such as a printing cylinder can be rocked to apply a strong printing pressure. Even if a separating operation is performed, the swing change distance can be very small, so that the noise at the time of collision can be significantly reduced. At the same time, it is possible to reduce unnecessary dimension portions provided before and after the stencil leading edge locking mechanism where printing pressure cannot be applied, so that the outer diameter of the drum of the plate cylinder can be reduced, which is effective for downsizing the stencil printing apparatus. Become.
[0022]
According to a second aspect of the present invention, in the plate cylinder according to the first aspect, the base paper leading end locking mechanism includes a metal sheet disposed on an outer peripheral surface of the drum along a drum axis direction, and a surface of the metal sheet. And the pressure-sensitive adhesive layer provided thereon.
[0023]
Therefore, the invention according to claim 1 can be easily realized only by disposing the metal sheet provided with the pressure-sensitive adhesive layer on the outer surface of the drum along the drum axial direction.
[0024]
According to a third aspect of the present invention, in the plate cylinder of the first aspect, the base paper leading end locking mechanism is provided along a drum axis direction on an outer peripheral surface of a non-opening portion of the porous cylindrical drum. It consists of an adhesive layer.
[0025]
Therefore, the invention according to claim 1 can be easily realized by simply providing the pressure-sensitive adhesive layer directly along the drum axial direction on the outer peripheral surface of the non-opening portion of the porous cylindrical drum. The mechanism can be further reduced in thickness.
[0026]
According to a fourth aspect of the present invention, in the plate cylinder according to any one of the first to third aspects, the pressure-sensitive adhesive layer is formed of a double-sided pressure-sensitive adhesive tape having a substrate.
[0027]
Therefore, by using a double-sided pressure-sensitive adhesive tape having a base material as a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer can be attached to a metal thin plate or an outer peripheral surface of a plate cylinder, and has an extremely simple and low-cost structure. The described invention can be realized.
[0028]
According to a fifth aspect of the present invention, in the plate cylinder according to any one of the first to fourth aspects, the stencil paper to which the pressure-sensitive adhesive layer is locked is a porous support made of a Japanese paper base made of 100% synthetic resin fibers. It is locked by attaching the porous support side to the pressure-sensitive adhesive layer.
[0029]
Therefore, as the stencil paper, a Japanese paper base made of 100% synthetic resin fibers is used for the porous support, and the porous support side is adhered to the pressure-sensitive adhesive layer. It is possible to prevent the problem that the film is sometimes easily torn and remains on the pressure-sensitive adhesive layer side. Further, a part of the fine fibers of the natural fibers, which mainly constitute the Japanese paper base, remain on the adhesive layer side of the surface, the adhesive strength of the adhesive layer is reduced, and the locking performance as a base paper leading edge locking mechanism is reduced. It is also possible to avoid such a problem.
[0030]
According to a sixth aspect of the present invention, in the plate cylinder according to the second, fourth or fifth aspect, the thin metal plate is supported so as to be openable and closable about an axis parallel to the drum axis and reciprocally movable in the circumferential direction of the drum. It has a displacement support mechanism.
[0031]
Accordingly, with respect to the base paper leading end locking mechanism by the combination of the metal sheet and the adhesive layer, the metal sheet is supported by the displacement support mechanism so as to be able to open and close freely around an axis parallel to the drum axis and reciprocate in the circumferential direction of the drum. By this, the leading end of the stencil sheet that has been locked can be peeled from the adhesive layer of the stencil leading edge locking mechanism by the opening and closing pivoting operation of the metal sheet and the reciprocating movement in the drum circumferential direction. The stencil sheet can be peeled off from the leading end side of the stencil sheet without rotating the plate cylinder in the plate discharging step.
[0032]
A stencil printing apparatus according to a seventh aspect of the present invention is a stencil printing machine according to any one of the first to sixth aspects, and receives a stencil sheet having been made stencil and supplies the leading end of the stencil sheet having been made stencil on the plate cylinder. A swingable base paper tip pressing member pressed against the adhesive layer in the base paper tip locking mechanism, a driving source for driving the base paper tip pressing member in the pressing direction, and winding around the drum outer peripheral surface of the plate cylinder A presser for pressing the produced stencil sheet on the printing paper; and an ink supply mechanism provided in the plate cylinder for supplying ink to the inner peripheral surface of the plate cylinder.
[0033]
Accordingly, since the stencil sheet is provided with a swingable stencil tip pressing member that receives the stencil stencil sheet and presses the leading end of the stencil sheet on the adhesive layer in the stencil tip locking mechanism on the plate cylinder, The leading end of the perforated stencil sheet can be securely locked to the pressure-sensitive adhesive layer.
[0034]
The stencil printing apparatus according to the invention of claim 8 is a stencil printing machine according to any one of claims 1 to 5, and receives the stencil sheet having been made stencil, and feeds the leading end of the stencil sheet having made stencil onto the plate cylinder. A swingable base paper tip pressing member pressed against the adhesive layer in the base paper tip locking mechanism, a driving source for driving the base paper tip pressing member in the pressing direction, and winding around the drum outer peripheral surface of the plate cylinder A press body for pressing the stencil sheet having been made into the printing paper, an ink supply mechanism provided in the plate cylinder to supply ink to an inner peripheral surface of the plate cylinder, and a wrapper wound around the drum outer peripheral surface of the plate cylinder. And a peeling and discharging device that peels off the stencil stencil sheet in the direction of peeling the leading end of the stencil sheet from the surface of the pressure-sensitive adhesive layer in order to remove the stencil sheet from the rear side in the rotation direction of the plate cylinder during plate discharging. .
[0035]
Therefore, the direction in which the stencil sheet with the stencil wrapped around the drum outer peripheral surface of the plate cylinder is peeled off from the rear end side in the rotation direction of the plate cylinder at the time of plate discharging, and the leading end of the stencil sheet with the stencil made is peeled off from the surface of the adhesive layer. The plate-making stencil sheet is peeled off from the surface of the pressure-sensitive adhesive layer, and the stencil sheet is peeled off from the rear end side in the rotation direction of the plate cylinder at the time of plate discharging. In this way, it is possible to perform a peeling operation at the time of plate discharge with a small force by a simple mechanism while securing a strong layer direction adhesive force.
[0036]
A stencil printing apparatus according to a ninth aspect of the present invention is the stencil printing machine according to the sixth aspect, wherein the stencil sheet is supplied with the stencil sheet, and the leading end of the stencil sheet is held by the stencil locking mechanism on the plate cylinder. A swingable stencil tip pressing member pressed against the adhesive layer, a drive source for driving the stencil tip pressing member in the pressing direction, and a perforated stencil wound around the drum outer peripheral surface of the plate cylinder A press body that presses the printing paper against the printing paper, an ink supply mechanism that is provided inside the plate cylinder and supplies ink to the inner peripheral surface of the plate cylinder, and a stencil sheet that has been stencil wound around the drum outer peripheral surface of the plate cylinder. At the time of plate discharging, the metal sheet is released from the outer peripheral surface of the drum by the displacement support mechanism and is moved and displaced in the drum circumferential direction along with the rotation of the plate cylinder, and is sequentially peeled from the leading end side in the rotation direction of the plate cylinder. Exhaustion Comprising apparatus and, a.
[0037]
Therefore, since the plate cylinder described in claim 6 is used as the plate cylinder, the leading end of the stencil sheet locked by the opening / closing pivoting operation of the thin metal plate and the reciprocating movement in the circumferential direction of the drum is used to lock the leading end of the stencil sheet. Therefore, it is possible to peel from the leading end side of the stencil sheet without reversely rotating the plate cylinder in the peeling plate discharging step.
[0038]
According to a tenth aspect of the present invention, in the stencil printing machine according to the eighth or ninth aspect, the separation and discharge processing of the stencil sheet with the stencil pre-printed is performed immediately after the stencil processing of the new stencil sheet with the new stencil. The image forming apparatus is provided with a stripping / discharge processing control unit to be executed according to conditions.
[0039]
Therefore, by performing the peeling and discharging process of the stencil sheet after the stencil is performed on the condition that the plate feeding processing of the new stencil sheet is performed immediately thereafter, the adhesive layer located on the surface is always stencil sheet. Can prevent the problem that the adhesive layer is exposed, and the adhesive force is reduced due to the adhesion of paper dust and dust in the air due to the exposure of the adhesive layer, and the locking performance is reduced. It can be maintained for a long time.
[0040]
BEST MODE FOR CARRYING OUT THE INVENTION
A first embodiment of the present invention will be described with reference to FIGS. This embodiment shows an example of application to a digital thermosensitive stencil printing apparatus.
[0041]
FIG. 1 is a longitudinal sectional front view schematically showing the entire internal structure of the stencil printing apparatus. The stencil printing apparatus has a digital copier function and includes a scanner 1 for reading a document image. The scanner 1 includes an openable and closable pressure plate 2 on an upper surface, and an ADF 3 for automatically and sequentially feeding and conveying a plurality of originals one by one. However, when making a stencil based on image data transmitted from a personal computer or the like, the scanner 1 is not essential, and the stencil printing apparatus may be configured to have only a printing machine function.
[0042]
In the main body of the stencil printing apparatus, a plate cylinder 4 that is driven to rotate clockwise is provided. Around the plate cylinder 4 where a required print image length is secured, a plate making device 5, a sheet feeding device 6, a printing pressure device 7, and a peeling plate discharging device 8 are provided. An ink supply mechanism 9 is provided inside the plate cylinder 4.
[0043]
The stencil making device 5 is a device for making a master by making a stencil sheet 10 by heating and melting in accordance with image data read by the scanner 1 or image data inputted from outside, and is a stencil sheet wound in a roll shape. A holding shaft 11 for holding the stencil 10, a thermal head 12 having a large number of heating elements for heating and perforating the stencil sheet 10, a platen roller 13 rotated by a stepping motor or the like to press the stencil sheet 10 against the thermal head 12, a thermal head The stencil 10 is formed by a cutter 14 for cutting the stencil sheet 10 having been heated and melt-punched by the cutter 12 into a predetermined length. The stencil sheet 10 that has been heated and melt-punched by the thermal head 12 is cut into a predetermined length by a cutter 14 to produce a stencil sheet 10a having a stencil shape (end of stencil making). It is wound on the outer peripheral surface of the body 4.
[0044]
The paper feeding device 6 includes a paper feeding roller 17 that sequentially feeds the printing paper 16 stacked on the paper feeding table 15 one by one from the topmost paper, a transport roller 18, and a registration roller that takes timing of printing on a printing unit. 19 and the like. Reference numeral 20 denotes a paper size detection sensor.
[0045]
The printing pressure device 7 can freely contact and separate from an outer peripheral surface of the plate cylinder 4 (more specifically, a stencil sheet 10a having a stencil wound around the outer peripheral surface of the plate cylinder 4) and press the printing paper 16 against the stencil sheet 10a having a stencil. The press roller 21 includes a press roller 21 as a pressing body, and a displacement mechanism 22 for performing a contact / separation operation of the press roller 21.
[0046]
The peeling plate discharging device 8 includes a pair of rollers 23 and 24 arranged near the plate cylinder 4 and a plate discharging box 25. Here, one of the rollers 23 is freely movable toward and away from the plate cylinder 4, and comes into contact with the outer peripheral surface of the plate cylinder 4 at the time of peeling and discharging, and is rotated in a direction opposite to the contact surface by the contact surface. Of the stencil sheet 10a having the stencil made as described above.
[0047]
Further, a transport device 27 that transports and discharges the printed printing paper 16 onto a paper discharge table 26 is provided downstream of the printing pressure device 7 in the transport direction. 28 is a side fence and 29 is an end fence.
[0048]
The ink supply mechanism 9 is disposed at a small interval between the ink pipe 30 which also serves as a holding shaft for rotatably holding the plate cylinder 4 and the inner peripheral surface of the plate cylinder 4, and rotates in the same direction as the plate cylinder 4. Ink roller 31 to be driven, doctor roller 32 disposed at a small interval between ink roller 31, ink reservoir 33 having a substantially wedge-shaped cross section formed between rollers 31 and 32, and the like. It consists of. As a result, ink is supplied through the ink pipe 30 by the driving of an ink pump (not shown), and the ink flows out of the plurality of ink holes 30 a formed in the ink pipe 30 and flows into the ink reservoir 33. The ink accumulated in the ink reservoir 33 is supplied to the inner peripheral surface of the plate cylinder 4 by the rotation of the ink roller 31, and the ink oozes out from the perforated portion of the perforated stencil sheet 10 a and is printed on the printing paper 16. Printing is performed by the transfer.
[0049]
Next, an example of the structure of the plate cylinder 4 will be described. FIG. 2 is a longitudinal sectional front view showing a part of the plate cylinder 4 in an enlarged manner, and FIG. 3 is a longitudinal sectional front view showing a part of the plate cylinder 4 in a further enlarged manner. The plate cylinder 4 basically formed in a cylindrical drum shape made of a porous metal having a large number of openings 41 is provided with a mesh screen 43 having an end bonded to the outer peripheral surface thereof with a bonding portion 42. , Covers the plate cylinder opening area. In such a plate cylinder 4, the pressure-sensitive adhesive layer 45 is provided on the surface of the non-opening portion 44 of the porous cylindrical drum so as to be directly exposed to the outside along the axial direction of the drum. A tip locking mechanism 46 is configured.
[0050]
Here, a double-sided adhesive tape as shown in FIG. 3 is used for the adhesive layer 45. That is, the tape structure has a front side adhesive 48 and a back side adhesive 49 on a PET film 47 as a base material, and is fixed by attaching the back side adhesive 49 on the non-opening portion 44. Have been. On the other hand, the stencil paper 10 whose leading end is locked by the adhesive layer 45 has a structure in which a thermoplastic resin film 50 and a porous Japanese paper base 51 are bonded together as shown in FIG. The setting is such that the side of the Japanese paper base 51 is attached to the front surface side adhesive 48.
[0051]
In addition, as shown in FIG. 4, the stencil sheet 10a is supplied between the plate cylinder 4 having the surface-side pressure-sensitive adhesive 48 and the plate making device 5 to receive the stencil sheet 10a. A pressing arm 53 as a base paper tip pressing member that is swingable about a spindle 52 that presses the tip of 10a onto the adhesive layer 45 on the plate cylinder 4, and is connected to a part of the pressing arm 53. A solenoid 54 as a drive source for driving the pressing arm 53 in the pressing direction, a spring 55 connected to a part of the pressing arm 53 and biasing the pressing arm 53 in a direction away from the pressing direction. , Are provided. An elastic body 56 made of foamed rubber or the like is provided on the pressing portion of the pressing arm 53 to ensure adhesion. Reference numerals 57 and 58 denote rollers arranged at the outlet of the plate making apparatus 5. In addition, a blower fan 59 that blows airflow that guides the leading end side of the stencil sheet 10 a, which is conveyed between the adhesive layer 45 (the plate cylinder 4) and the pressing arm 53, toward the pressing arm 53, is provided. Is provided.
[0052]
In such a configuration, the perforated stencil sheet 10a produced by the perforating apparatus 5 is synchronized with the position of the pressure-sensitive adhesive layer 45 on the plate cylinder 4, as shown in FIG. The paper is conveyed between 53. At this time, since the blowing airflow from the blower fan 59 is blown against the leading end of the stencil sheet 10a, the leading end of the stencil sheet 10a is sent out by a predetermined amount without sticking to the adhesive layer 45. And stop. Then, when the solenoid 54 is turned on at a predetermined timing, the pressing arm 53 swings around the support shaft 52, and the leading end of the stencil sheet 10 a is pressed and adhered onto the adhesive layer 45. As a result, the leading end portion of the stencil sheet 10 a having been made is stuck to the adhesive layer 45 and locked. At this time, since the elastic body 56 is interposed in the pressed portion, the adhesion of the leading end of the perforated stencil sheet 10a to the adhesive layer 45 becomes more reliable. Then, after the plate cylinder 4 is slightly rotated clockwise, the solenoid 54 is turned off, the pressing arm 53 is released from the plate cylinder 4 by the biasing force of the spring 55, and the rotation of the plate cylinder 4 is continued. The perforated stencil sheet 10a after the leading end is wound and adhered onto the mesh screen 43 by the ink present on the outer peripheral surface of the plate cylinder 4.
[0053]
In this manner, the leading end portion of the stencil sheet 10a having been made into a stencil sheet is detachably locked to the outer peripheral surface of the plate cylinder 4 by the adhesive layer 45 as shown in FIG. In this case, since the base paper leading end locking mechanism 46 is simply constituted by the adhesive layer 45, there is no need to provide a pair of plate members unlike a conventional combination of a clamp plate and a clamp base, and the structure is extremely thin. be able to. Therefore, even if the press roller 21 is subjected to the swinging contact / separation operation to apply a strong printing pressure, the swing change distance can be very small, and the noise at the time of collision can be greatly reduced. . At the same time, the useless dimension portions provided before and after the stencil leading edge locking mechanism 46 to which the printing pressure cannot be applied can be reduced. Become a target.
[0054]
The state of engagement of the leading end of the stencil sheet 10a with the pressure-sensitive adhesive layer 45 will be considered. In the present embodiment, as described above, a stencil sheet 10a having a structure in which the thermoplastic resin film 50 and the porous Japanese paper base 51 are bonded to each other, and the Japanese paper base 51 side is bonded to the adhesive layer 45. It is set as follows. Here, the back side adhesive 49 side is rarely peeled off once applied, but the front side adhesive 48 side is subjected to a process in which a new perforated stencil sheet 10a is repeatedly attached and peeled off. Here, in the case where the thermoplastic resin film 50 is bonded to the pressure-sensitive adhesive layer 45 on the side of the thermoplastic resin film 50, the thickness of the thermoplastic resin film 50 is very thin, about 1 to 2 μm. There is a problem. In this regard, in the present embodiment, since the side of the Japanese paper base 51 is attached to the adhesive layer 45 as described above, such a problem can be solved.
[0055]
The porous stencil base of the stencil paper 10 is usually made of natural Japanese paper mixed with some synthetic fibers. However, in the case of such a material, when the stencil sheet 10a is peeled off from the surface-side pressure-sensitive adhesive 48 side in the peeling and discharging process, a part of the fine fibers mainly composed of the natural fibers constituting the porous Japanese paper base is reduced to the surface-side pressure-sensitive adhesive. There is a problem that it remains on the 48 side. If such a phenomenon is repeated and accumulated many times, the adhesive force of the surface-side adhesive 48 decreases, and the locking performance of the base paper leading edge locking mechanism 46 decreases.
[0056]
In this regard, in the present embodiment, the porous Japanese paper base 51 of the stencil sheet 10 is also made of 100% synthetic fibers and does not contain natural fibers. The problem of remaining on the side is less likely to occur. This is because in the case of a synthetic fiber, its thickness is uniform and local separation hardly occurs.
[0057]
By the way, according to the base paper leading end locking mechanism 46 using the adhesive layer 45 as in the present embodiment, as shown in FIG. In the direction (planar direction), a strong holding force can be exerted by a strong adhesive force even when pulled with a very strong force P1. On the other hand, when pulled in a direction substantially perpendicular to the surface of the pressure-sensitive adhesive layer 45, a comparison is made. It has a feature that it is easily peeled off even with a weak force P2.
[0058]
As a specific example, for example, a simple 15-mm wide and 300-mm-long Scotch double-sided adhesive tape ST416 of 15 mm width and 300 mm length is used as the pressure-sensitive adhesive layer 45 (double-sided pressure-sensitive adhesive tape), and a report master m-80 is used as the stencil sheet 10. From the experimental results, it was found that the horizontal tensile force P1 was 10 kgf or more (a force that would cause the stencil sheet 10 itself to break), but the vertical tensile force P2 was at most about 200 gf.
[0059]
Therefore, in the case of the present embodiment, the peeling plate discharging process can be easily realized by utilizing such features. With reference to FIGS. 6A and 6B, a description will be given of a separation plate discharging process utilizing such features. The stencil sheet 10a adhesively wound around the outer peripheral surface of the plate cylinder 4 with ink has a blank portion 10b where no ink is attached at the rear end opposite to the front end locking side. By rotating the roller 23 in the opposite direction (counterclockwise) and rotating the roller 23 in a direction in which the roller 23 comes into contact with the plate cylinder 4 in the opposite direction as shown in FIG. Are peeled in order from the rear end portion 10b side, and the peeling / conveying proceeds by the rotation of the plate cylinder 4 in the counterclockwise direction and the rotation of the rollers 23 and 24. Then, when finally reaching the pressure-sensitive adhesive layer 45, as shown in FIG. 6B, a peeling operation is performed to peel off the stencil sheet 10a in a direction perpendicular to the pressure-sensitive adhesive layer 45, and with a weak force. Peeling of the tip can be performed.
[0060]
FIG. 7 shows a schematic configuration example of a control system of the stencil printing apparatus according to the present embodiment. This control system includes, as a main component, a control unit 61 having a computer configuration including a CPU, a ROM, and a RAM. The control unit 61 includes a printing machine 5, a sheet feeding device 6, a printing drum 4, a press roller 21, and the like. The section 62, the peeling plate discharging device 8, the operation panel 63 and the like are connected.
[0061]
A control example of the stripping and discharging process of the present embodiment executed by the control unit 61 will be described with reference to a schematic flowchart shown in FIG. First, when the start key is pressed through the operation panel 63 or the like (Y in S1), the stencil sheet 10a wound around the outer peripheral surface of the plate cylinder 4 in the previous printing process is subjected to the stripping and discharging process (S2). ). Next, a stencil making process is performed on the stencil 10 based on the image data (S3), and a stencil feeding process of winding the stencil made stencil 10a around the outer peripheral surface of the plate cylinder 4 is executed (S4). That is, the front end portion is pressed onto the adhesive layer 45 to be locked, and the front end portion and the subsequent portions are wound around the outer peripheral surface as the plate cylinder 4 rotates. Then, the printing paper 16 is fed while rotating the plate cylinder 4 and the press roller 21, and ink is supplied to perform printing on the printing paper 16 (S5). When printing of a predetermined number of sheets is completed (Y in S6), the current printing operation is terminated, but the apparatus is in a standby state until the start key for the next printing is pressed (Y in S1). In other words, the stencil sheet 10a wound on the outer peripheral surface of the plate cylinder 4 this time is left as it is wound until plate feeding processing for the next printing is performed. Such a series of processing of steps S1 to S6 is executed as a function of the separation and plate discharge processing control means.
[0062]
As described above, according to the present embodiment, the separation and discharge process of the plate-making stencil 10a is executed on the condition that the plate-feeding process of the next new plate-making stencil is performed immediately thereafter. The pressure-sensitive adhesive layer 45 located on the surface can always be covered by the leading end of the stencil sheet 10a. Therefore, when the pressure-sensitive adhesive layer 45 is exposed, paper dust in the apparatus and dust in the air adhere to the pressure-sensitive adhesive layer, and the adhesive strength is reduced. Can be avoided, and the locking performance can be maintained for a long period of time.
[0063]
A second embodiment of the present invention will be described with reference to FIG. The same parts as those described in the first embodiment are denoted by the same reference numerals, and description thereof is omitted (the same applies to the following embodiments).
[0064]
In the above-described embodiment, the base paper leading end locking mechanism 46 is configured by directly providing the adhesive layer 45 such as a double-sided adhesive tape on the non-opening portion 44 of the plate cylinder 4 itself. In the embodiment, the metal sheet 71 provided in the region of the non-opening portion 44 of the plate cylinder 4 and the adhesive layer 45 stuck on the surface of the metal sheet 71 constitute the base paper leading end locking mechanism 72. . Here, the thin metal plate 71 is provided to be elongated in parallel with the drum axis, and both ends thereof are fixed to the flange 73 of the plate cylinder 4 by screws 74. The pressure-sensitive adhesive layer 45 itself is the same as in the first embodiment.
[0065]
According to the present embodiment, the metal sheet 71 having the adhesive layer 45 adhered to the surface thereof in advance may be positioned and fixed to the non-opening portion 44 of the plate cylinder 4, and requires a separate member. The work of attaching 45 can be performed on the thin metal plate 71 and can be easily realized.
[0066]
A third embodiment of the present invention will be described with reference to FIG. In this embodiment, as in the case of the above-described second embodiment, a base paper leading end locking mechanism 72 including a metal thin plate 71 and an adhesive layer 45 is configured. And is supported by a displacement support mechanism 75 so as to be openable and closable about an axis parallel to the drum axis and reciprocally movable in the circumferential direction of the drum. That is, outside the flanges 73 at both ends of the plate cylinder 4, there are provided support arms 77, which are rotatable and displaceable in the direction of arrow A around the drum central axis 76 and have a length about the plate cylinder radius. Both ends of the thin metal plate 71 are supported by a clamper arm 79 that is rotatable about a support shaft 78 provided near the center. Here, the support shaft 78 is located on the rear end side of the thin metal plate 71 when viewed from the leading end side of the stencil sheet 10a, and the support shaft 78 allows the metal thin plate 71 to open and close around an axis parallel to the drum axis. It is rotatable. In addition, a support arm 77 that is rotatable and displaceable about a drum central axis 76 is reciprocally movable in the circumferential direction of the drum. Here, a gear 81 is provided on the support arm 77 and is driven to rotate about a shaft 80 by a drive transmission mechanism (not shown). A partial gear portion meshing with the gear 81 is provided around a support shaft 78 of the clamper arm 79. 82 are formed. Further, a spring 83 for urging the support arm 77 in the clockwise direction is provided, and a stopper piece 84 for restricting the movement amount of the support arm 77 in the clockwise direction is provided on the flange 73.
[0067]
In such a configuration, except during the peeling operation, the metal thin plate 71 is closed on the outer peripheral surface of the non-opening portion 44 of the plate cylinder 4 as shown in FIG. Then, by the above-described winding process, the perforated stencil sheet 10a is wound around the outer peripheral surface of the plate cylinder 4 in such a manner that the leading end thereof is stuck to the adhesive layer 45 on the thin metal plate 71 and locked. Offered to
[0068]
Thereafter, at the time of the peeling and discharging process of the stencil sheet 10a, the driving mechanism (not shown) of the stencil printing apparatus causes the gear 81 to move in the arrow B direction (counterclockwise) while the shaft 80 is fixedly held. A rotational driving force is provided. As a result, the clamper arm 79 is rotated and displaced in the direction of the arrow C (clockwise) shown in FIGS. 10A and 10B, and the metal sheet 71 supported by the clamper arm 79 is also separated from the outer peripheral surface of the plate cylinder 4. An open displacement operation is performed in such a state as to stand up. Finally, as shown in FIG. 10B, it is raised to a state substantially perpendicular to the outer peripheral surface. At this time, the leading end of the stencil sheet 10a is still attached and locked on the adhesive layer 45 of the metal thin plate 71.
[0069]
In this way, the plate cylinder 4 is driven to rotate in the direction of arrow D (clockwise) as shown in FIGS. 10B and 10C with the clamper arm 79 kept open. Then, the stopper piece 83 moves away from the support arm 77, and at the same time, the stencil sheet 10a closely contacted with the ink on the outer peripheral surface of the plate cylinder 4 also gradually moves away. As shown in (c), the leading end of the stencil sheet 10a is also peeled off at the pressure-sensitive adhesive layer 45 in such a manner that it is gradually peeled off. In this manner, the opening and moving operations of the metal thin plate 71 on the outer peripheral surface of the plate cylinder 4 allow the leading end side of the stencil sheet 10a to be easily separated from the adhesive layer 45 with a small force and free. State. As a result, the peeling / discharge processing of the stencil sheet 10a by the peeling plate discharging device 8 can be performed not from the rear end side but from the front end side of the stencil sheet 10a.
[0070]
【The invention's effect】
According to the first aspect of the present invention, since there is provided a stencil tip locking mechanism having a pressure-sensitive adhesive layer on its surface for releasably locking the leading end of the stencil sheet, the combination of the clamp plate and the clamp base is provided. It is only necessary to lock the perforated stencil sheet on the pressure-sensitive adhesive layer on the surface without providing a pair of plate members as in the above, it can be made extremely thin, and it is necessary to apply a strong printing pressure to the printing cylinder etc. Even if the pressing body is subjected to the swinging contact / separation operation, the swinging change distance can be very small, so that the noise at the time of collision can be significantly reduced, and at the same time, provided before and after the base paper leading end locking mechanism. Since a useless dimension portion to which the printing pressure cannot be applied can be reduced, the outer diameter of the drum of the plate cylinder can also be reduced, which is effective in reducing the size of the stencil printing apparatus.
[0071]
According to the second aspect of the present invention, the base paper leading end locking mechanism includes a metal thin plate disposed on the outer peripheral surface of the drum along the axial direction of the drum and an adhesive layer provided on the surface of the metal thin plate. Therefore, the invention according to claim 1 can be easily realized only by disposing the metal sheet having the adhesive layer on the surface thereof along the drum axial direction on the outer peripheral surface of the drum.
[0072]
According to the third aspect of the present invention, since the base paper leading end locking mechanism is formed of the adhesive layer provided along the drum axis direction on the outer peripheral surface of the non-opening portion of the porous cylindrical drum, The invention according to claim 1 can be easily realized only by directly providing an adhesive layer along the axial direction of the drum on the outer peripheral surface of the non-opening portion of the cylindrical drum. It is possible to further reduce the thickness.
[0073]
According to the fourth aspect of the present invention, since the double-sided pressure-sensitive adhesive tape having the base material is used as the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer may be stuck on a metal thin plate or an outer peripheral surface of a plate cylinder, and is a very simple and low-cost structure Thus, the invention according to any one of claims 1 to 3 can be realized.
[0074]
According to the fifth aspect of the present invention, in the plate cylinder according to any one of the first to fourth aspects, a stencil paper is made of a Japanese paper base made of 100% synthetic resin fibers as the porous support, and the porous support side is used. Is attached to the pressure-sensitive adhesive layer, so that the thermoplastic resin film portion is easily torn when the stencil sheet is peeled off and remains on the pressure-sensitive adhesive layer side, thereby preventing the occurrence of a problem. Part of the fine fibers of natural fibers, which mainly constitute the Japanese paper base, remain on the pressure-sensitive adhesive layer side of the surface, and the adhesive force of the pressure-sensitive adhesive layer is reduced, and the locking performance as a base paper tip locking mechanism is reduced. Problems can also be avoided.
[0075]
According to the sixth aspect of the present invention, in the plate cylinder according to the second, fourth or fifth aspect, the metal sheet is fixed to the drum axis by the displacement support mechanism with respect to the base paper leading end locking mechanism by the combination of the metal sheet and the adhesive layer. The stencil sheet is locked by opening and closing rotation of the metal sheet and reciprocating movement of the drum in the circumferential direction because the metal plate is supported so as to be openable and closable about a parallel axis and reciprocally movable in the circumferential direction of the drum. Of the stencil sheet can be peeled from the pressure-sensitive adhesive layer of the stencil leading edge locking mechanism, so that the stencil sheet can be peeled from the leading edge side of the stencil sheet without rotating the plate cylinder in the peeling and discharging step.
[0076]
According to the stencil printing apparatus of the present invention, the stencil sheet is supplied with the stencil sheet, and the leading end of the stencil sheet is pressed against the pressure-sensitive adhesive layer of the stencil locking mechanism on the plate cylinder. Since the movable stencil tip pressing member is provided, the leading end of the stencil sheet having the stencil made can be securely locked to the adhesive layer.
[0077]
According to the stencil printing apparatus of the invention, the stencil sheet with the stencil wrapped around the drum of the plate cylinder is peeled off from the rear end side in the rotation direction of the plate cylinder at the time of discharging the stencil sheet. Is provided in the direction of peeling off the leading end of the stencil sheet from the surface of the pressure-sensitive adhesive layer. Is peeled in the direction in which it is peeled off from the surface of the pressure-sensitive adhesive layer, whereby a peeling operation at the time of plate discharging can be performed with a small force by a simple mechanism while securing strong layer-direction adhesive force.
[0078]
According to the stencil printing apparatus of the ninth aspect, since the plate cylinder of the sixth aspect is used as the plate cylinder, the stencil printing apparatus is locked by the opening / closing rotation operation of the metal sheet and the reciprocating movement in the drum circumferential direction. The leading end of the stencil sheet thus peeled can be peeled from the adhesive layer of the stencil leading edge locking mechanism, and thus can be peeled from the leading end side of the stencil sheet without rotating the plate cylinder in the peeling and discharging step.
[0079]
According to the tenth aspect of the present invention, in the stencil printing apparatus according to the eighth or ninth aspect, the plate-making stencil sheet is peeled and discharged, and immediately thereafter, the next new stencil sheet is supplied. By performing the above conditions, the pressure-sensitive adhesive layer located on the surface can always be covered by the leading end of the stencil sheet. Therefore, the exposure of the pressure-sensitive adhesive layer causes paper dust in the apparatus and dust in the air. It is possible to avoid the problem that the adhesive force is reduced due to the adhesion of the adhesive, and the locking performance can be maintained for a long time.
[Brief description of the drawings]
FIG. 1 is a vertical sectional front view schematically showing the entire internal structure of a stencil printing apparatus according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional front view showing a part of a plate cylinder in an enlarged manner.
FIG. 3 is a longitudinal sectional front view showing a part of the enlarged view.
FIG. 4 is a longitudinal sectional front view for explaining the winding operation of the leading end of the base paper.
FIG. 5 is a vertical sectional front view for explaining features of the pressure-sensitive adhesive layer.
FIG. 6 is a vertical sectional front view showing a peeling operation.
FIG. 7 is a block diagram illustrating a schematic configuration example of a control system of the stencil printing apparatus.
FIG. 8 is a schematic flowchart illustrating a control example of a peeling plate discharging process.
FIG. 9 is a longitudinal sectional front view showing a plate cylinder according to a second embodiment of the present invention.
FIG. 10 is a longitudinal sectional front view showing a peeling operation according to a third embodiment of the present invention in the order of steps.
FIG. 11 is a schematic front view showing a configuration example of a conventional stencil printing apparatus.
FIG. 12 is a vertical sectional front view for explaining a defect caused by the conventional method (2).
[Explanation of symbols]
4 plate cylinder
8 Stripping plate discharging device
9 Ink supply mechanism
10 stencil paper
10a Pre-printed stencil paper
16 Printing paper
21 Pressing body
44 Non-opening part
45 Adhesive layer
46 Base paper tip locking mechanism
47 substrate
50 porous support
51 Japanese paper base
53 Pressing member
54 Drive source
71 Metal sheet
72 Base paper tip locking mechanism
75 Displacement support mechanism

Claims

A plate cylinder having a stencil tip locking mechanism having a pressure-sensitive adhesive layer on a surface of a part of the outer periphery of a drum, the adhesive layer for releasably locking the leading end of a stencil sheet.

The base paper tip locking mechanism includes:
A metal sheet disposed on the drum outer peripheral surface along the drum axis direction;
The pressure-sensitive adhesive layer provided on the surface of the metal sheet,
The plate cylinder according to claim 1, further comprising:

The base paper tip locking mechanism includes:
2. The plate cylinder according to claim 1, comprising the pressure-sensitive adhesive layer provided on the outer peripheral surface of the non-opening portion of the porous cylindrical drum along the drum axis direction.

The plate cylinder according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer is formed of a double-sided pressure-sensitive adhesive tape having a substrate.

The stencil paper to which the pressure-sensitive adhesive layer is locked is formed by using a Japanese paper base made of 100% synthetic resin fibers for a porous support, and locked by attaching the porous support side to the pressure-sensitive adhesive layer. A plate cylinder according to any one of claims 1 to 4.

6. The plate cylinder according to claim 2, further comprising a displacement support mechanism for supporting the thin metal plate so as to be freely opened and closed and rotatable around an axis parallel to the drum axis and reciprocally movable in the circumferential direction of the drum.

A plate cylinder according to any one of claims 1 to 6,
A swingable stencil tip pressing member for receiving the stencil stencil sheet and pressing the leading end of the stencil sheet on the adhesive layer in the stencil tip locking mechanism on the plate cylinder;
A drive source for driving the base paper tip pressing member in the pressing direction,
A pressing body that presses the prepressed stencil wrapped around the drum outer peripheral surface of the plate cylinder against printing paper;
An ink supply mechanism provided in the plate cylinder to supply ink to an inner peripheral surface of the plate cylinder;
A stencil printing apparatus comprising:

A plate cylinder according to any one of claims 1 to 5,
A swingable stencil tip pressing member for receiving the stencil stencil sheet and pressing the leading end of the stencil sheet on the adhesive layer in the stencil tip locking mechanism on the plate cylinder;
A drive source for driving the base paper tip pressing member in the pressing direction,
A pressing body that presses the prepressed stencil wrapped around the drum outer peripheral surface of the plate cylinder against printing paper;
An ink supply mechanism provided in the plate cylinder to supply ink to an inner peripheral surface of the plate cylinder;
The direction in which the prepressed stencil sheet wound around the drum outer peripheral surface of the plate cylinder is sequentially peeled from the rear end side in the rotation direction of the plate cylinder during plate discharging, and the leading end of the prepressed stencil sheet is peeled off from the surface of the adhesive layer. A plate removing device for peeling off
A stencil printing apparatus comprising:

A plate cylinder according to claim 6,
A swingable stencil tip pressing member for receiving the stencil stencil sheet and pressing the leading end of the stencil sheet on the adhesive layer in the stencil tip locking mechanism on the plate cylinder;
A drive source for driving the base paper tip pressing member in the pressing direction,
A pressing body that presses the prepressed stencil wrapped around the drum outer peripheral surface of the plate cylinder against printing paper;
An ink supply mechanism provided in the plate cylinder to supply ink to an inner peripheral surface of the plate cylinder;
When the stencil sheet with the stencil wound around the drum outer peripheral surface of the plate cylinder is discharged, the metal thin plate is released from the outer peripheral surface of the drum by the displacement support mechanism when the stencil sheet is discharged, and is displaced in the drum circumferential direction with the rotation of the plate cylinder. A separation plate discharging device that separates the plate cylinder in order from the rotation direction front end side,
A stencil printing apparatus comprising:

The stencil printing according to claim 8 or 9, further comprising a separation / discharge processing control means for executing the separation / discharge processing of the plate-making stencil sheet immediately after the next new plate-making stencil sheet is supplied. apparatus.