JP3636953B2

JP3636953B2 - Crease member, crease template, crease device and cardboard sheet

Info

Publication number: JP3636953B2
Application number: JP32560599A
Authority: JP
Inventors: 孝之竹内
Original assignee: Nippon Die Steel Co Ltd
Current assignee: Nippon Die Steel Co Ltd
Priority date: 1999-02-02
Filing date: 1999-11-16
Publication date: 2005-04-06
Anticipated expiration: 2019-11-16
Also published as: JP2000289124A

Description

【０００１】
【発明の属する技術分野】
この発明は、段ボールシートに折曲げ用の罫線を罫入れする押罫部材、その押罫部材が取付けられた型板および罫入れ装置並びに段ボールシートに関するものである。
【０００２】
【従来の技術】
一般に、段ボールシートの打抜きによって、例えば図１０に示すような段ボール箱形成用のブランクＡ₁を形成する場合、ボードから成る型板にブランクＡ₁の外径を打抜く外形打抜き刃を取付けると共に、その外形打抜き刃の内側に、上記ブランクＡ₁の縦罫線Ｌ₁および横罫線Ｌ₂を罫入れする罫入れ用の押罫部材を取付けるようにしている。
【０００３】
ここで、縦罫線Ｌ₁は、段ボールシートＡの波状に成形された中芯Ｓ₂の段目にほぼ平行し、一方、横罫線Ｌ₂は上記中芯の段目と直交する方向に延びている。
【０００４】
上記縦罫線Ｌ₁および横罫線Ｌ₂を罫入れする押罫部材として、図１１（Ｉ）に示す金属製帯状板から成るものと、図１１（II）に示すように、合成樹脂の成形品から成るものが従来から知られている。
【０００５】
図１１（Ｉ）に示す押罫部材６０は、幅が２０数ｍｍ程度で、厚みが０．７ｍｍ乃至３．０ｍｍ程度の帯状板６１の一側縁部を罫入れ部６２とし、その罫入れ部６２により段ボールシートを押し込んで溝状の縦罫線Ｌ₁および横罫線Ｌ₂を罫入れするようにしている。
【０００６】
一方、図１１（II）に示す合成樹脂の成形品から成る押罫部材６３は、帯状基板６４の表面に凸円弧状のシート押圧面６５と、そのシート押圧面６５の幅方向中央部に帯状基板６４の両端方向に延びる突条６６を形成し、前記シート押圧面６５により段ボールシートを押し潰し、その押し潰し部の幅方向中央を突条６６で押し込んで溝状の縦罫線Ｌ₁および横罫線Ｌ₂を罫入れするようにしている。
【０００７】
【発明が解決しようとする課題】
ところで、図１１（Ｉ）に示す押罫部材６０においては、段ボールシートに罫入れを施す罫入れ部６２の表面が全長にわたって滑らかであり、その罫入れ部６２で厚み方向に弾性を有する段ボールシートを押し込んで罫線を罫入れするため、鮮明な罫線を入れることができず、鮮明度の高い罫線を入れようとして押し込み量を多くすると、段ボールシートのライナが局部に引き伸ばされ、図１２に示すように、段ボールシートＡのライナＳ₁に割れを生じる場合がある。
【０００８】
一方、図１１（II）に示す押罫部材６３において、シート押圧面６５によって段ボールシートを押し潰し、その押し潰し部の幅方向中央部を突条６６により押し潰して罫線を罫入れするため、段ボールシートＡのライナＳ₁が局部的に大きく引き伸ばされることがなく、前記ライナＳ₁に割れを生じさせることなく罫線を罫入れすることができるという特徴を有する。
【０００９】
しかし、罫入れを施す突条６６は表面が全長にわたって凹凸のない均一な面であるため、罫入れ時、突条６６は全長にわたって段ボールシートＡをほぼ均一に押圧することになり、鮮明な形状の折曲げ性の良好な罫線を罫入れすることができない。
【００１０】
ここで、図１０に示すブランクＡ₁の形成装置として、ロータリ式の罫入れ打抜き装置が知られている。この罫入れ打抜き装置においては、アンビルロールに対設したダイロールの外周に型板を取付け、両ロール間に送り込まれる段ボールシートを型板に取付けられた打抜き刃によって打抜き、同時に、押罫部材によって罫入れを行うようにしている。
【００１１】
ところで、型板に取付けられた押罫部材が、図１１（Ｉ）および（II）に示すような押罫部材６０、６３の場合、罫入れ部６２および罫入れ用突条６６は全長にわたって表面が滑らかであるため、段ボールシートＡに対する摩擦係合力が弱く、罫入れ部６２および罫入れ用突条６６と段ボールシートの相互間で滑りを生じる場合がある。特に、段ボールシートＡの走行速度が高速になると、罫入れ部６２および突条６６と段ボールシートＡの相互間で滑りが生じ易く、寸法精度の高い打抜きを行なうことができない問題がある。
【００１２】
また、段ボールシートに対して罫線を入れる装置として、上記のような型板を用いずに、機械的に罫線を入れるようにしたものが知られている。例えば、相対的に逆方向に回転される一対の回転軸の一方に罫入れロールを取付け、他方に受けロールを取付け、その罫入れロールと受けロール間に送り込まれる段ボールシートを罫入れロールの外周に設けられた突条により押圧して段ボールシートの移送方向に罫線を罫入れするようにした罫入れ装置が存在する。
【００１３】
ところで、上記罫入れ装置においても、罫入れロールの外周に設けられた罫入れ用の突条の表面が円周方向の全体にわたって滑らかであるため、図１１（Ｉ）、（II）に示す押罫部材６０、６３と同様に、段ボールシートＡに対して折曲げ性の優れた罫線を罫入れすることができない。
【００１４】
この発明の課題は、段ボールシートに対して折曲げ性に優れた罫線を罫入れすることができるようにした押罫部材、型板、罫入れ装置並びに折曲げ性が良好な段ボールシートを提供することである。
【００１５】
【課題を解決するための手段】
上記の課題を解決するために、この発明に係る押罫部材においては、段ボールシートに、波状中芯の段目にほぼ平行な罫線を罫入れする帯状板から成る押罫部材において、段ボールシートを押し込む罫入れ部の厚みを０．７〜３．０ｍｍ程度とし、そのシート押圧面の断面形状を円弧状又は両側縁に丸みを有する平面状とし、その罫入れ部の全長にわたって長さ方向に多数の切欠部を等ピッチで形成し、その切欠部の深さを段ボールシートの厚みより小さくし、シート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成可能にした構成を採用している。
【００１６】
【００１７】
【００１８】
【００１９】
上記の構成から成る押罫部材の罫入れ部を段ボールシートに押し付けることにより、切欠部間に形成された突起部において段ボールシートは強く押し込まれ、切欠部での位置では押し込み量が少ないため、深溝部と浅溝部とが交互に並ぶ罫線を形成することができる。
【００２０】
【００２１】
【００２２】
ここで、押罫部材の罫入れ部に設けられた切欠部の形状は任意であり、角形、台形、円弧状、Ｖ形等の任意の形状を採ることができる。また、切欠部の形成ピッチ、深さおよび長さは、段ボールシートの厚み、ライナの紙質に応じて適宜に決定する。切欠部の深さについては、その深さが段ボールシートの厚みを超えると、浅溝部を形成することができないため、段ボールシートの厚みより小さくする。
【００２３】
この発明に係る型板においては、段ボールシートに、波状中芯の段目にほぼ平行な罫線を罫入れする押罫部材が取付けられた罫入れ用型板において、前記押罫部材の段ボールシートに罫入れする罫入れ部の厚みを０．７〜３．０ｍｍ程度とし、そのシート押圧面の断面形状を円弧状又は両側縁に丸みを有する平面状とし、その罫入れ部の全長にわたって長さ方向に多数の切欠部を等ピッチで形成し、その切欠部の深さを段ボールシートの厚みより小さくし、シート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成可能にした構成を採用している。
【００２４】
また、この発明に係る罫入れ装置においては、受板に対して進退自在に設けられた型板に押罫部材を取付け、前記型板の前進時に押罫部材により受板で支持された段ボールシートを押圧して波状中芯の段目にほぼ平行に罫線を罫入れする罫入れ装置において、前記押罫部材の段ボールシートを押圧する罫入れ部の厚みを０．７〜３．０ｍｍ程度とし、そのシート押圧面の断面形状を円弧状又は両側縁に丸みを有する平面状とし、その罫入れ部の全長にわたって長さ方向に多数の切欠部を等ピッチで形成し、その切欠部の深さを段ボールシートの厚みより小さくし、シート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成可能にした構成を採用している。
また、この発明に係る段ボールシートにおいては、前記発明の押罫部材、型板の押罫部材並びに罫入れ装置の押罫部材の押し込みによってシート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成した構成を採用したのである。
さらに、この発明に係る罫入れ装置においては、アンビルロールに対設されたダイロールの外周に型板を取付け、その型板に取付けられた押罫部材によって両ロール間に送り込まれる段ボールシートに波状中芯の段目にほぼ平行な罫線を罫入れする罫入れ装置において、前記押罫部材の段ボールシートに罫入れする罫入れ部の厚みを０．７〜３．０ｍｍ程度とし、そのシート押圧面の断面形状を円弧状又は両側縁に丸みを有する平面状とし、その罫入れ部の全長にわたって長さ方向に多数の切欠部を等ピッチで形成し、その切欠部の深さを段ボールシートの厚みより小さくし、シート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成可能にした構成を採用したのである。
【００２５】
また、この発明に係る罫入れ装置においては、受けロールと罫入れロールとを相対的に逆方向に回転し、罫入れロールの外周に設けられた罫入れ用突条によって前記両ロール間に送り込まれる段ボールシートに波状中芯の段目にほぼ平行に罫線を形成する罫入れ装置において、前記罫入れ用突条の厚みを０．７〜３．０ｍｍ程度とし、その段ボールシートを押し込む外周面の断面形状を円弧状又は両側縁に丸みを有する平面状とし、その突条の外周に全長にわたって長さ方向に多数の切欠部を等ピッチで形成し、その切欠部の深さを段ボールシートの厚みより小さくし、シート表面からの深さが深い深溝部と深さが浅い浅溝部が交互に並ぶ溝状の折曲げ用の罫線を形成可能にした構成を採用したのである。
【００２６】
【発明の実施の形態】
以下、この発明の実施の形態を図１乃至図９に基づいて説明する。図１に示すように、段ボールシートＡは、表裏のライナＳ₁間に波状中芯Ｓ₂を設けている。この段ボールシートＡには、折曲げ時に内側となる面からの押し潰しによって波状中芯Ｓ₂の段目にほぼ平行な折曲げ用の罫線ａが形成されている。
【００２７】
罫線ａは、深溝部ａ₁と浅溝部ａ₂とが交互に並ぶ直線状の溝から成っている。
【００２８】
上記のように、深溝部ａ₁と浅溝部ａ₂を交互に連続させることにより、深溝部ａ₁におけるライナＳ₁は浅溝部ａ₂におけるライナＳ₁より深く押し潰されるため、深溝部ａ₁と浅溝部ａ₂との相互間に段差が形成され、前記深溝部ａ₁はミシン目模様に現れて、比較的鮮明な罫線ａを得ることができる。
【００２９】
このため、段ボールシートＡを罫線ａに沿ってきわめて精度よく折曲げることができる。
【００３０】
図２は、この発明に係る段ボールシートＡの他の例を示す。この例では、段ボールシートＡに波状中芯Ｓ₂の段目にほぼ平行する押し潰し部ｂを形成し、その押し潰し部ｂの幅方向中央部に深溝部ａ₁と浅溝部ａ₂とが直線状に交互に並ぶ溝状の罫線ａを形成している。
【００３１】
ここで、押し潰し部ｂは、幅方向の中央部で深く、両側に至るに従って深さが次第に浅くなっている。
【００３２】
上記のように、押し潰し部ｂを形成し、その押し潰し部ｂの幅方向中央部に罫線ａを形成することにより、罫線ａの罫入れ部におけるライナＳ₁の伸びは少なくなり、深さの深い折曲げ性の良好な罫線ａをライナＳ₁に割れを生じさせることなく形成することができる。
【００３３】
図３は、段ボールシートに罫入れを施す罫入れ装置を示す。この罫入れ装置は、段ボールシートＡを支持する受板１と、この受板１に対して進退自在の型板２とを有し、型板１にはレーザ加工等によって罫取付け溝３が形成され、その罫取付け溝３に押罫部材１０が圧入により取付けられている。
【００３４】
図４（Ｉ）、（II）に示すように、押罫部材１０は、幅が２０数ｍｍ程度で厚みが０．７〜３．０ｍｍ程度の金属製の帯状板１１から成り、その帯状板１１の一側縁部は罫入れ部１２とされている。この罫入れ部１２の断面形状はＲ形とされ、その罫入れ部１２の長さ方向に多数の切欠部１３が等ピッチで形成されている。
【００３５】
なお、罫入れ部１２の断面形状は円弧形に限定されるものではない。例えば、図６（Ｉ）に示すようなＶ形、図６（II）に示すような角形、図６（III ）に示すように、厚みの中央部に帯状板の長さ方向に延びる溝を形成した溝形、図６（IV）に示すように、厚みの中央部に帯状板の長さ方向に延びる突条を形成した突形であってもよい。
【００３６】
図４（II）は上記罫入れ部１２の一部を拡大して示し、その罫入れ部１２に形成された切欠部１３は図示のような円弧状の他、図５（Ｉ）に示す台形状や図５（II）に示すＶ形、あるいは図５（III ）に示すような角形等の形状を採用してもよい。
【００３７】
上記切欠部１３の深さｈ、長さＬ及びピッチＰは、段ボールシートのライナの紙質や厚み、強度、押罫を形成する帯状板１１の厚み、罫入れ部１２の断面形状に応じて適宜に決定する。
【００３８】
実施の形態では、深さｈ、長さＬおよびピッチＰを、ｈ＝０．２ｍｍ、Ｌ＝２．５ｍｍ、Ｐ＝４ｍｍとしている。
【００３９】
ここで、切欠部１３の両端は、円弧面１４を介して罫入れ部１２の表面に滑らかに連続している。
【００４０】
いま、型板２の下方に設けられた受板１で段ボールシートＡを支持し、その受板１に対して型板２を下降させると、段ボールシートＡに対する押罫部材１０の罫入れ部１２の押し込みによって、段ボールシートＡに罫線ａが入れられる。
【００４１】
このとき、罫入れ部１２は、切欠部１３間に形成された突起部１５が段ボールシートＡを最初に押し込むと共に、切欠部１３の内周が段ボールシートＡを引き続いて押し込むことになり、突起部１５の押し込み量は切欠部１３の位置での押し込み量より大きいため、段ボールシートＡに、図１に示すように、深溝部ａ₁と浅溝部ａ₂とが交互に並ぶ直線状の罫線ａを形成することができる。
【００４２】
ここで、段ボールシートＡは、突起部１５と対応する位置で強く押し込まれるため、輪郭が比較的鮮明な深溝部ａ₁を形成することができると共に、浅溝部ａ₂でのライナＳ₁の伸び量は小さく、上記深溝部ａ₁の周縁部ではその浅溝部ａ₂との段差分が相当する量だけ多く伸ばされるだけであるため、ライナＳ₁に割れを発生させることはない。
【００４３】
図７は罫入れ打抜き装置を示す。この装置は、アンビルロール２０に対設したダイロール２１の外周に円弧状の型板２２を取付け、そのアンビルロール２０とダイロール２１間に送り込まれる段ボールシートＡを型板２２に取付けられた打抜き刃２３によって所定の形状に打抜くと共に、型板２２に取付けられた押罫部材３０によって段ボールシートＡに罫入れを施すようにしている。
【００４４】
ここで、段ボールシートＡの移送方向に罫線を形成する押罫部材３０は、図７（II）に示すように、円弧状の金属製帯状板３１の外径側を罫入れ部３２とし、その罫入れ部３２の外周に図４（II）および図５（Ｉ）、（II）、（III ）で示した切欠部１３を等間隔に形成している。
【００４５】
上記押罫部材３０によって段ボールシートＡに罫入れを施すことにより、深溝部ａ₁と浅溝部ａ₂とが交互に連続する図１に示す罫線ａを罫入れすることができる。
【００４６】
また、上記押罫部材３０を用いることにより、罫入れを施す罫入れ部３２は切欠部１３の形成によって凹凸が連続しているため、段ボールシートＡに対する係合力が強く、押罫部材３０と段ボールシートＡの相互間で滑りが生じるのを防止することができ、寸法精度の高い打抜きを行うことができる。
【００４７】
図８（Ｉ）、（II）は押罫部材の他の例を示す。この押罫部材４０は帯状基板４１の裏面に形成された平坦な取付面４２の幅方向中央部に浅い溝部４３を設けている。また、帯状基板４１の表面には、その帯状基板４１の幅方向中央部を厚肉とし、両側に至るに従って厚みを次第に薄くするシート押圧面４４を形成し、このシート押圧面４４の幅方向中央部に帯状基板４１の両端方向に長く延びる罫入れ用の突条４５を設け、その突条４５の全長にわたって切欠部４６を等間隔に形成している。
【００４８】
上記の構成から成る押罫部材４０を図３に示す罫入れ打抜き装置の型板２あるいは図７に示す罫入れ打抜き装置の型板２２に釘止めあるいは接着による手段を介して取付けて段ボールシートＡに罫入れを施すことにより、段ボールシートＡはシート押圧面４４で押し込まれて、図８（II）に示すように、幅方向中央部で深く、両側に至るに従って次第に浅くなる押し潰し部ｂが形成される。また、押し潰し部ｂの幅方向中央部が突条４５により押し込まれて罫線ａが形成される。
【００４９】
このとき、突条４５には切欠部４６が等間隔に形成されているため、切欠部４６間に形成された突起部４７は段ボールシートＡを強く押し込むことになり、突起部４７と対応する位置に深溝部ａ₁が形成される。
【００５０】
ここで、突条４５に形成された切欠部４６がシート押圧面４４に達する深さであると、切欠部４６の位置では段ボールシートＡを押圧することはないが、突起部４７が段ボールシートＡのライナＳ₁を押し込む深溝部ａ₁の形成時に、突起部４７間のライナＳ₁は深溝部ａ₁の方向に引き込まれるため、深溝部ａ₁間にきわめて浅い浅溝部ａ₂が形成され、図１に示すように、深溝部ａ₁と浅溝部ａ₂とが交互に連続する罫線ａが形成される。
【００５１】
上記のように、シート押圧面４４で段ボールシートＡを押し潰し、その押し潰し部ｂに罫線ａを罫入れすることにより、突起部４７と対応する位置でのライナＳ₁の伸びは比較的少なく、ライナＳ₁に割れを生じさせることなく罫入れを施すことができる。
【００５２】
図９（Ｉ）、（II）は罫入れ装置の他の例を示す。この例では、段ボールシートＡを図９（II）の矢印方向に送る上下一対の送りローラ５０の下流側に一対の回転軸５１、５２を上下に設け、上側回転軸５１に罫入れロール５３を取付け、下側回転軸５２に受けロール５４を取付けている。
【００５３】
また、罫入れロール５３の外周に罫入れ用の突条５５を設け、その突条５５の外周に図４（II）あるいは図５（Ｉ）、（II）、（III ）に示す切欠部１３の１つを等間隔に形成している。
【００５４】
いま、一対の送りローラ５０によって図９（Ｉ）の矢印方向に回転する罫入れロール５３と受けロール５４間に段ボールシートＡを送り込むと、罫入れロール５３の突条５５が段ボールシートＡを押し込むため、段ボールシートＡに罫線ａを形成することができる。
【００５５】
このとき、突条５５には切欠部１３が等間隔に形成されているため、段ボールシートＡには、図１に示すように、深溝部ａ₁と浅溝部ａ₂が交互に並ぶ溝状の罫線ａが形成される。
【００５６】
なお、図９（II）に示す例では突条５５の断面形状をＲ形としたが、図６（Ｉ）乃至（IV）に示す断面形状としてもよい。
【００５７】
【発明の効果】
以上のように、この発明においては、段ボールシートに深溝部と浅溝部とが交互に並ぶ溝状の罫線を押し潰しにより形成したことにより、深溝部と浅溝部での押し潰し量の相違によって両溝部間に段差が形成され、折曲げ性の良好な鮮明な罫線を得ることができ、段ボールシートを上記罫線に沿ってきわめて精度よく折曲げることができる。
【００５８】
また、段ボールシートに幅方向の中央部で深く、両側に至るに従って次第に浅くなる押し潰し部を形成し、その押し潰し部の幅方向中央部に深溝部と浅溝部が交互に連続する罫線を形成したことにより、罫線の罫入れ時に段ボールシートのライナに割れが生じるのを防止することができ、深さの深い折曲げ性の良好な罫線を形成することができる。
【００５９】
また、帯状板から成る押罫部材の罫入れ部に沿って多数の切欠部を間隔をおいて形成したことにより、その罫入れ部を段ボールシートに押し付けることによって、切欠部間に形成された突起部が段ボールシートを強く押し込み、切欠部の位置では押し込み力が弱いため、深溝部と浅溝部とが交互に並ぶ溝状の罫線を罫入れすることができる。
【００６０】
また、帯状基板の表面に形成されたシート押圧面に突条を形成し、その突条の長さ方向に多数の切欠部を間隔をおいて形成した罫入部材で段ボールシートを押し込むことにより、段ボールシートはシート押圧面で押し潰され、その押し潰し部の幅方向中央部に深溝部と浅溝部とが交互に連続する罫線を罫入れすることができ、段ボールシートのライナに割れを生じさせることなく罫線を罫入れすることができる。
【図面の簡単な説明】
【図１】（Ｉ）はこの発明に係る段ボールシートの一部分を示す斜視図、（II）は縦断正面図、（III ）は縦断側面図
【図２】（Ｉ）はこの発明に係る段ボールシートの他の例を示す一部分の斜視図、（II）は縦断側面図
【図３】（Ｉ）はこの発明に係る罫入れ装置の縦断正面図、（II）は罫入れ時の状態を示す縦断正面図
【図４】（Ｉ）は図３の罫入れ装置に用いられた押罫部材の斜視図、（II）は一部を拡大して示す正面図
【図５】（Ｉ）乃至（III ）は押罫部材に形成された切欠部の他の例を示す正面図
【図６】（Ｉ）乃至（IV）は押罫部材に形成された罫入れ部の他の例を示す断面図
【図７】（Ｉ）は罫入れ装置の他の例を示す正面図、（II）は罫入部材の一部分を示す斜視図
【図８】（Ｉ）はこの発明に係る押罫部材の他の例を示す斜視図、（II）はその断面図
【図９】（Ｉ）はこの発明に係る罫入れ装置の他の例を示す正面図、（II）は側面図
【図１０】段ボール箱のブランクを示す一部切欠正面図
【図１１】（Ｉ）、（II）は従来の押罫部材を示す斜視図
【図１２】段ボールシートのライナに割れが生じた断面図
【符号の説明】
Ａ段ボールシート
Ｓ₂波状中芯
ａ罫線
ａ₁深溝部
ａ₂浅溝部
ｂ押し潰し部
１受板
２型板
１０押罫部材
１１帯状板
１２罫入れ部
１３切欠部
２０アンビルロール
２１ダイロール
３０押罫部材
３２罫入れ部
４０押罫部材
４１帯状基板
４４シート押圧面
４５突条
４６切欠部
５３罫入れロール
５４受けロール
５５突条[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ruled member for marking a folding ruled line on a cardboard sheet, a template having the ruled member attached thereto, a ruler, and a cardboard sheet .
[0002]
[Prior art]
In general, when a blank A ₁ for forming a corrugated cardboard box as shown in FIG. 10 is formed by punching a corrugated cardboard sheet, for example, an outer punching blade for punching the outer diameter of the blank A ₁ is attached to a template made of a board, Inside the outer shape punching blade, a ruled member for crease for crease the vertical ruled line L ₁ and the horizontal ruled line L ₂ of the blank A ₁ is attached.
[0003]
Here, the vertical ruled line L ₁ is substantially parallel to the step of the corrugated core S ₂ of the corrugated cardboard sheet A, while the horizontal ruled line L ₂ extends in a direction perpendicular to the core step. Yes.
[0004]
As the ruled line member for crease the vertical ruled line L ₁ and the horizontal ruled line L ₂ , a metal strip-like plate shown in FIG. 11 (I) and a synthetic resin molded product as shown in FIG. 11 (II) What consists of is conventionally known.
[0005]
A ruled member 60 shown in FIG. 11 (I) has a width of about 20 mm and a side edge of a strip 61 having a thickness of about 0.7 mm to 3.0 mm as a crease 62, and the crease. The cardboard sheet is pushed in by the part 62 so as to rule the groove-like vertical ruled line L ₁ and horizontal ruled line L ₂ .
[0006]
On the other hand, a ruled member 63 made of a synthetic resin molded product shown in FIG. 11 (II) has a convex arcuate sheet pressing surface 65 on the surface of the band-shaped substrate 64 and a band-shaped central portion in the width direction of the sheet pressing surface 65. forming a ridge 66 extending across the direction of the substrate 64, the sheet pressing surface crushed cardboard sheet by 65, a groove-like vertical line L ₁ and the horizontal push the width direction center of the crushed portion in protrusion 66 borders L ₂ are so as to put ruffled.
[0007]
[Problems to be solved by the invention]
By the way, in the ruled member 60 shown in FIG. 11 (I), the surface of the crease portion 62 for making a crease on the cardboard sheet is smooth over the entire length, and the crease portion 62 has elasticity in the thickness direction. Since the ruled line is creased by pressing, a clear ruled line cannot be entered, and if the amount of pushing is increased to insert a ruled line with high definition, the liner of the cardboard sheet is stretched locally, as shown in FIG. In addition, the liner S ₁ of the cardboard sheet A may be cracked.
[0008]
On the other hand, in the ruled member 63 shown in FIG. 11 (II), the cardboard sheet is crushed by the sheet pressing surface 65, and the center part in the width direction of the crushed part is crushed by the ridge 66 to rule the ruled line. The liner S ₁ of the cardboard sheet A is not greatly stretched locally, and the ruled line can be creased without causing the liner S ₁ to crack.
[0009]
However, since the ridge 66 to be creased has a uniform surface with no unevenness over the entire length, the ridge 66 presses the corrugated cardboard sheet A substantially uniformly over the entire length when creased, resulting in a sharp shape. It is not possible to crease a ruled line with good bendability.
[0010]
Here, as a forming apparatus for the blank A ₁ shown in FIG. 10, a rotary ruled punching apparatus is known. In this crease punching device, a die plate is attached to the outer periphery of a die roll provided on an anvil roll, and a corrugated cardboard sheet fed between both rolls is punched by a punching blade attached to the die plate, and at the same time, a ruled member is used to make a crease. I try to put it in.
[0011]
By the way, when the ruled members attached to the template are ruled members 60 and 63 as shown in FIGS. 11 (I) and (II), the ruled part 62 and the ruled protrusion 66 are on the entire surface. Therefore, the frictional engagement force with respect to the corrugated cardboard sheet A is weak, and the crease 62 and the crease ridge 66 may slip between the corrugated cardboard sheet. In particular, when the traveling speed of the corrugated cardboard sheet A becomes high, there is a problem that slippage between the ruled portion 62 and the ridge 66 and the corrugated cardboard sheet A is likely to occur, and punching with high dimensional accuracy cannot be performed.
[0012]
Further, as a device for putting a ruled line on a corrugated cardboard sheet, a device that can put a ruled line mechanically without using the above template is known. For example, a crease roll is attached to one of a pair of rotating shafts that are rotated in the opposite directions, a receiving roll is attached to the other, and the corrugated cardboard sheet fed between the crease roll and the receiving roll is attached to the outer periphery of the crease roll. There is a crease device which is creased in the direction of the corrugated cardboard sheet by pressing it with a ridge provided on the cardboard.
[0013]
By the way, also in the above crease device, since the surface of the ridge for crease provided on the outer periphery of the crease roll is smooth throughout the circumferential direction, the press shown in FIGS. 11 (I) and (II). Like the ruled members 60 and 63, a ruled line having excellent bendability cannot be ruled on the corrugated cardboard sheet A.
[0014]
An object of the present invention is to provide a crease member, a template, a crease device , and a corrugated cardboard sheet having a good bendability , which can crease a ruled line having excellent bendability with respect to the corrugated cardboard sheet . It is to be.
[0015]
[Means for Solving the Problems]
In order to solve the above problems, in the ruled member according to the present invention, in the ruled member formed of a belt-like plate for marking a ruled line substantially parallel to the corrugated core step on the cardboard sheet, The thickness of the crease portion to be pushed in is about 0.7 to 3.0 mm, and the cross-sectional shape of the sheet pressing surface is an arc shape or a planar shape having rounded edges on both sides, and many in the length direction over the entire length of the crease portion. The notch is formed at an equal pitch, the depth of the notch is smaller than the thickness of the corrugated cardboard sheet, and the groove-like folds in which the deep groove part having a deep depth from the sheet surface and the shallow groove part having a shallow depth are alternately arranged. A configuration that enables the formation of a ruled line for bending is employed.
[0016]
[0017]
[0018]
[0019]
By pressing the crease part of the ruled member having the above structure against the corrugated sheet, the corrugated sheet is strongly pushed in the projection formed between the notches, and the amount of pushing is small at the position of the notch. A ruled line in which the portions and the shallow groove portions are alternately arranged can be formed.
[0020]
[0021]
[0022]
Here, the shape of the notch provided in the ruled part of the ruled member is arbitrary, and any shape such as a square, trapezoid, arc, or V shape can be adopted. Further, the formation pitch, depth and length of the notches are appropriately determined according to the thickness of the cardboard sheet and the paper quality of the liner. About the depth of a notch part, when the depth exceeds the thickness of a cardboard sheet, since a shallow groove part cannot be formed, it makes it smaller than the thickness of a cardboard sheet.
[0023]
In the template according to the present invention, in the crease template in which a crease member for crease a ruled line substantially parallel to the corrugated core step is attached to the corrugated cardboard sheet, The thickness of the crease portion to be creased is about 0.7 to 3.0 mm, the cross-sectional shape of the sheet pressing surface is an arc shape or a planar shape with rounded edges on both sides, and the length direction is over the entire length of the crease portion A groove shape in which a large number of notches are formed at an equal pitch, the depth of the notches is smaller than the thickness of the corrugated cardboard sheet, and deep grooves with shallow depth from the sheet surface and shallow grooves with shallow depth are alternately arranged. The configuration that enables the formation of a folding ruled line is adopted.
[0024]
Further, in the crease device according to the present invention, a corrugated member is attached to a template provided so as to be movable forward and backward with respect to the receiving plate, and the corrugated cardboard sheet is supported by the receiving plate by the ruled member when the template moves forward. In the crease device that creases the ruled line almost parallel to the corrugated core step by pressing the thickness of the crease part that presses the cardboard sheet of the crease member is about 0.7 to 3.0 mm, The cross-sectional shape of the sheet pressing surface is an arc shape or a flat shape with rounded edges on both sides, and a number of notches are formed at equal pitches in the length direction over the entire length of the ruled portion, and the depth of the notches is set. A configuration is adopted in which the thickness is smaller than the thickness of the corrugated cardboard sheet, and a groove-shaped ruled line for bending in which a deep groove portion having a deep depth from the sheet surface and a shallow groove portion having a shallow depth are alternately arranged can be formed.
Further, in the corrugated cardboard sheet according to the present invention, the deep groove portion having a deep depth from the sheet surface and the shallow depth due to the pressing of the ruled member of the invention, the ruled member of the template, and the ruled member of the crease forming device. A configuration in which groove-shaped folding ruled lines in which shallow groove portions are alternately arranged is employed.
Furthermore, in the crease device according to the present invention, a template is attached to the outer periphery of a die roll provided on the anvil roll, and the corrugated cardboard sheet fed between the two rolls by a ruled member attached to the template is being corrugated. In a crease device that creases a ruled line substantially parallel to the core step, the thickness of the crease portion to be creased on the corrugated cardboard sheet of the crease member is about 0.7 to 3.0 mm, and the sheet pressing surface The cross-sectional shape is an arc shape or a flat shape with rounded edges on both sides, and a number of notches are formed at equal pitches in the length direction over the entire length of the crease, and the depth of the notches is determined by the thickness of the cardboard sheet. The structure is made smaller and can form a groove-like folding ruled line in which deep groove portions having a deep depth from the sheet surface and shallow groove portions having a shallow depth are alternately arranged.
[0025]
Further, in the crease device according to the present invention, the receiving roll and the crease roll are rotated relatively in opposite directions, and are fed between the two rolls by the crease protrusion provided on the outer periphery of the crease roll. In the crease forming apparatus for forming a ruled line substantially parallel to the corrugated core step on the corrugated cardboard sheet, the ridge for the crease has a thickness of about 0.7 to 3.0 mm, and the outer peripheral surface into which the cardboard sheet is pushed The cross-sectional shape is an arc shape or a flat shape with rounded edges on both sides, and a number of notches are formed at equal pitches along the entire length of the outer circumference of the ridge, and the depth of the notches is the thickness of the cardboard sheet. A configuration is adopted in which a groove-like crease ruled line in which a deep groove portion having a deep depth from the sheet surface and a shallow groove portion having a shallow depth are alternately arranged can be formed.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the corrugated cardboard sheet A is provided with a corrugated core S ₂ between the front and back liners S ₁ . The cardboard sheet A, borders a for generally parallel folding to the stage of the corrugated medium S ₂ is formed by a crush from surface to be the inner during folding.
[0027]
The ruled line a is composed of linear grooves in which deep groove portions a ₁ and shallow groove portions a ₂ are alternately arranged.
[0028]
As described above, by continuous deep groove portion a ₁ and shallow groove a ₂ alternately, for liner S ₁ in the deep groove portion a ₁ is crushed deeper liner S ₁ in shallow groove a _2, deep groove portion a ₁ And a shallow groove part a ₂ , a step is formed, and the deep groove part a ₁ appears in a perforated pattern, and a relatively clear ruled line a can be obtained.
[0029]
For this reason, the cardboard sheet A can be bent along the ruled line a with extremely high accuracy.
[0030]
FIG. 2 shows another example of the corrugated cardboard sheet A according to the present invention. In this example, a crushed portion b that is substantially parallel to the step of the corrugated core S ₂ is formed on the corrugated cardboard sheet A, and a deep groove portion a ₁ and a shallow groove portion a ₂ are formed at the center in the width direction of the crushed portion b. Groove-shaped ruled lines a arranged alternately in a straight line are formed.
[0031]
Here, the crushing portion b is deep at the center in the width direction, and the depth gradually decreases as it reaches both sides.
[0032]
As described above, to form a crushed portion b, by forming a ruled line a in the width direction central portion of the crushed portion b, the elongation of the liner S ₁ in the ruling insertion portion of the ruled line a is reduced, the depth the deep bending of good borders a can be formed without causing cracks in the liner S _1.
[0033]
FIG. 3 shows a scoring device for scoring cardboard sheets. This crease forming apparatus has a receiving plate 1 for supporting the corrugated cardboard sheet A and a mold plate 2 that can be moved forward and backward with respect to the receiving plate 1, and a ruled mounting groove 3 is formed in the mold plate 1 by laser processing or the like. The crease member 10 is attached to the crease attachment groove 3 by press fitting.
[0034]
As shown in FIGS. 4 (I) and (II), the ruled member 10 is composed of a metal strip 11 having a width of about 20 mm and a thickness of about 0.7 to 3.0 mm. One side edge portion 11 is a ruled portion 12. The cross-sectional shape of the ruled portion 12 is R-shaped, and a large number of notches 13 are formed at equal pitches in the length direction of the ruled portion 12.
[0035]
Note that the cross-sectional shape of the ruled portion 12 is not limited to an arc shape. For example, a V shape as shown in FIG. 6 (I), a square shape as shown in FIG. 6 (II), and a groove extending in the length direction of the strip plate at the center of the thickness as shown in FIG. 6 (III). As shown in FIG. 6 (IV), the groove shape formed may be a protrusion shape in which a protrusion extending in the length direction of the belt-like plate is formed at the center of the thickness.
[0036]
FIG. 4 (II) shows a part of the crease part 12 in an enlarged manner, and the notch part 13 formed in the crease part 12 has a circular arc shape as shown in the figure, as well as the base shown in FIG. 5 (I). A shape such as a V shape shown in FIG. 5 (II) or a square shape shown in FIG. 5 (III) may be adopted.
[0037]
The depth h, length L, and pitch P of the notch 13 are appropriately determined according to the paper quality, thickness, and strength of the liner of the corrugated cardboard sheet, the thickness of the strip plate 11 that forms the ruled line, and the cross-sectional shape of the ruled part 12. To decide.
[0038]
In the embodiment, the depth h, the length L, and the pitch P are set to h = 0.2 mm, L = 2.5 mm, and P = 4 mm.
[0039]
Here, both ends of the notch 13 are smoothly connected to the surface of the ruled part 12 via the arcuate surface 14.
[0040]
Now, when the corrugated sheet A is supported by the receiving plate 1 provided below the template 2 and the template 2 is lowered with respect to the receiving plate 1, the crease 12 of the ruled member 10 with respect to the corrugated cardboard A is provided. Is pushed into the cardboard sheet A.
[0041]
At this time, the crease portion 12 has the projection 15 formed between the notches 13 that first pushes the cardboard sheet A, and the inner periphery of the notch 13 continues to push the cardboard sheet A. 15 is larger than the amount of pushing at the position of the notch 13, so that a straight ruled line a in which deep grooves a ₁ and shallow grooves a ₂ are alternately arranged is formed on the corrugated cardboard sheet A as shown in FIG. Can be formed.
[0042]
Here, since the corrugated cardboard sheet A is strongly pushed in at a position corresponding to the protrusion 15, it is possible to form the deep groove a ₁ having a relatively clear outline, and to extend the liner S ₁ in the shallow groove a _2. The amount is small, and the peripheral portion of the deep groove portion a ₁ is merely extended by a corresponding amount from the shallow groove portion a ₂ , so that the liner S ₁ is not cracked.
[0043]
FIG. 7 shows a ruled punching device. In this apparatus, an arc-shaped template 22 is attached to the outer periphery of a die roll 21 facing the anvil roll 20, and a corrugated cardboard sheet A fed between the anvil roll 20 and the die roll 21 is attached to the template 22. The cardboard sheet A is creased by the stamping member 30 attached to the template 22.
[0044]
Here, the ruled member 30 for forming a ruled line in the transport direction of the corrugated cardboard sheet A, as shown in FIG. 7 (II), the outer diameter side of the arc-shaped metal strip 31 is a ruled part 32, Notches 13 shown in FIG. 4 (II) and FIGS. 5 (I), (II), and (III) are formed at equal intervals on the outer periphery of the ruled portion 32.
[0045]
By scoring the corrugated cardboard sheet A with the scoring member 30, the ruled line a shown in FIG. 1 in which the deep groove portions a ₁ and the shallow groove portions a ₂ continue alternately can be made.
[0046]
Further, by using the ruled member 30, the crease part 32 to be creased is continuously uneven due to the formation of the notch part 13, so that the engaging force with the cardboard sheet A is strong, and the ruler member 30 and the cardboard Slip between the sheets A can be prevented and punching with high dimensional accuracy can be performed.
[0047]
8 (I) and (II) show other examples of the ruled member. The ruled member 40 is provided with a shallow groove 43 at the center in the width direction of a flat mounting surface 42 formed on the back surface of the belt-like substrate 41. Further, a sheet pressing surface 44 is formed on the surface of the band-shaped substrate 41 so that the central portion in the width direction of the band-shaped substrate 41 is thick, and the thickness is gradually reduced toward both sides. A ridge 45 for ruled lines extending long in the both end directions of the belt-like substrate 41 is provided at the portion, and the notches 46 are formed at equal intervals over the entire length of the ridge 45.
[0048]
The corrugated member 40 having the above structure is attached to the template 2 of the ruled punching apparatus shown in FIG. 3 or the template 22 of the ruled punching apparatus shown in FIG. As shown in FIG. 8 (II), the corrugated sheet A is pushed in by the sheet pressing surface 44. As shown in FIG. 8 (II), there is a crushing portion b that is deep at the center in the width direction and gradually becomes shallower as it reaches both sides. It is formed. Further, the center portion in the width direction of the crushed portion b is pushed by the protrusion 45 to form a ruled line a.
[0049]
At this time, since the notches 46 are formed at equal intervals in the protrusion 45, the protrusions 47 formed between the notches 46 strongly push the cardboard sheet A, and the positions corresponding to the protrusions 47. A deep groove a ₁ is formed in
[0050]
Here, if the notch 46 formed in the protrusion 45 has a depth that reaches the sheet pressing surface 44, the corrugated sheet A is not pressed at the position of the notch 46, but the protrusion 47 is not corrugated. during the formation of the liner S ₁ deep groove portion a ₁ is pushed to the liner S ₁ between the projections 47 because they are drawn in the direction of the deep groove portion a _1, very shallow shallow groove a ₂ between the deep groove portion a ₁ is formed, As shown in FIG. 1, a ruled line a in which deep groove portions a ₁ and shallow groove portions a ₂ continue alternately is formed.
[0051]
As described above, crushed cardboard sheet A by the sheet pressing surface 44, by putting ruffled borders a in its crushed portion b, the elongation of the liner S ₁ at a position corresponding to the projecting portion 47 is relatively small It is possible to make a ruled line without causing the liner S ₁ to crack.
[0052]
9 (I) and 9 (II) show another example of a ruler. In this example, a pair of rotary shafts 51 and 52 are provided on the downstream side of the pair of upper and lower feed rollers 50 for feeding the cardboard sheet A in the direction of the arrow in FIG. A receiving roll 54 is attached to the lower rotating shaft 52.
[0053]
Further, a ridge 55 for crease is provided on the outer periphery of the crease roll 53, and the notch 13 shown in FIG. 4 (II) or FIGS. 5 (I), (II), (III) is provided on the outer periphery of the ridge 55. Are formed at equal intervals.
[0054]
When the corrugated sheet A is fed between the ruler roll 53 and the receiving roll 54 that rotate in the direction of the arrow in FIG. 9 (I) by the pair of feed rollers 50, the protrusion 55 of the ruler roll 53 pushes the cardboard sheet A into it. Therefore, the ruled line a can be formed on the cardboard sheet A.
[0055]
At this time, since the notches 13 are formed at equal intervals in the protrusion 55, the corrugated cardboard sheet A has a groove shape in which the deep groove portions a ₁ and the shallow groove portions a ₂ are alternately arranged as shown in FIG. A ruled line a is formed.
[0056]
In the example shown in FIG. 9 (II), the cross-sectional shape of the protrusion 55 is R-shaped, but the cross-sectional shape shown in FIGS. 6 (I) to (IV) may be used.
[0057]
【The invention's effect】
As described above, according to the present invention, the groove-like ruled lines in which the deep groove portions and the shallow groove portions are alternately arranged on the corrugated cardboard sheet are formed by crushing. A step is formed between the groove portions, a clear ruled line with good bendability can be obtained, and the cardboard sheet can be folded along the ruled line with extremely high accuracy.
[0058]
In addition, a crushed portion is formed in the corrugated cardboard sheet deeper in the center in the width direction and gradually shallower as it reaches both sides, and a ruled line in which the deep groove portion and the shallow groove portion are alternately continuous is formed in the center portion in the width direction of the crushed portion. As a result, it is possible to prevent cracks in the liner of the corrugated cardboard sheet at the time of ruled ruled lines, and it is possible to form ruled lines having a deep depth and good bendability.
[0059]
In addition , by forming a large number of notches at intervals along the ruled portion of the ruled member made of a belt-like plate, the protrusions formed between the notched portions by pressing the ruled portion against the cardboard sheet Since the portion strongly pushes the corrugated cardboard sheet and the pushing force is weak at the position of the notch portion, it is possible to rule a groove-like ruled line in which deep groove portions and shallow groove portions are alternately arranged.
[0060]
In addition, by forming ridges on the sheet pressing surface formed on the surface of the belt-like substrate, by pressing the cardboard sheet with a crease member formed with a large number of notches in the length direction of the ridges, The cardboard sheet is crushed by the sheet pressing surface, and a ruled line in which deep groove portions and shallow groove portions are alternately continuous can be creased at the center in the width direction of the crushed portion, causing a crack in the liner of the cardboard sheet. The ruled line can be ruled without any trouble.
[Brief description of the drawings]
FIG. 1 (I) is a perspective view showing a part of a cardboard sheet according to the present invention, (II) is a longitudinal front view, (III) is a longitudinal side view. FIG. 2 (I) is a corrugated cardboard sheet according to the present invention. The perspective view of the part which shows the other example, (II) is a vertical side view. [FIG. 3] (I) is the vertical front view of the crease forming apparatus according to the present invention. Front view [FIG. 4] (I) is a perspective view of a ruled member used in the crease forming apparatus of FIG. 3, (II) is a partially enlarged front view [FIG. 5] (I) to (III) ) Is a front view showing another example of the notch formed in the ruled member. FIG. 6 is a sectional view showing another example of the ruled part formed in the ruled member. 7A is a front view showing another example of the crease forming apparatus, FIG. 8II is a perspective view showing a part of the crease member, and FIG. 8I is another view of the crease member according to the present invention. Perspective view , (II) is a cross-sectional view thereof. FIG. 9 (I) is a front view showing another example of a crease forming apparatus according to the present invention, and (II) is a side view. FIG. 10 is a partial view showing a blank of a cardboard box. Cutaway front view [Fig. 11] (I) and (II) are perspective views showing a conventional ruled member. [Fig. 12] Cross-sectional view in which a liner of a cardboard sheet is cracked. [Explanation of symbols]
A Corrugated sheet S ₂ Corrugated core a Ruled line a ₁ Deep groove part a ₂ Shallow groove part b Crushing part 1 Receiving plate 2 Mold plate 10 Ruled member 11 Strip plate 12 Ruled part 13 Notch part 20 Anvil roll 21 Die roll 30 Ruled line Member 32 Ruled part 40 Ruled member 41 Strip substrate 44 Sheet pressing surface 45 Projection line 46 Cutout part 53 Ruled line roll 54 Receiving roll 55 Projection line

Claims

In a ruled member made of a belt-like plate that creases a ruled line almost parallel to a corrugated core step on a corrugated cardboard sheet, the thickness of the ruled part into which the cardboard sheet is pushed is about 0.7 to 3.0 mm. The cross-sectional shape of the pressing surface is an arc shape or a flat shape with rounded edges on both sides, and a number of notches are formed at equal pitches in the length direction over the entire length of the crease, and the depth of the notches is a corrugated cardboard sheet. A ruled line member having a groove-like folding ruled line in which a deep groove portion having a deep depth from a sheet surface and a shallow groove portion having a shallow depth are alternately arranged.

In a crease template in which a crease member that creases a ruled line that is substantially parallel to the corrugated core step is attached to the corrugated sheet, the thickness of the crease part to be creased on the corrugated sheet of the crease member The cross-sectional shape of the sheet pressing surface is an arc shape or a planar shape with rounded edges on both sides, and a large number of notches are arranged at equal pitches in the length direction over the entire length of the ruled portion. The depth of the notch can be made smaller than the thickness of the corrugated cardboard sheet, and a groove-like crease ruled line can be formed in which deep grooves with a deep depth from the sheet surface and shallow grooves with a shallow depth are alternately arranged. A crease template characterized by the fact that

A ruled member is attached to a template provided so as to be able to move forward and backward with respect to the receiving plate, and the cardboard sheet supported by the receiving plate is pressed by the ruled member when the template moves forward, so that the corrugated core is almost leveled. In a crease device that creases crease lines in parallel, the thickness of the crease portion for pressing the corrugated cardboard sheet of the crease member is about 0.7 to 3.0 mm, and the cross-sectional shape of the sheet pressing surface is an arc shape or both sides It has a flat shape with rounded edges, and a large number of notches are formed at equal pitches in the length direction over the entire length of the crease, and the depth of the notches is made smaller than the thickness of the corrugated cardboard sheet. A crease forming apparatus characterized in that a groove-like crease line can be formed in which a deep groove portion having a deep depth and a shallow groove portion having a shallow depth are alternately arranged.

The depth from the sheet surface is increased by pressing the ruled member according to claim 1, the ruled member of the crease template according to claim 2, or the ruled member of the crease device according to claim 3. A corrugated cardboard sheet having a groove-like folding ruled line in which deep grooves and shallow grooves having a shallow depth are alternately arranged.

A template is attached to the outer periphery of the die roll facing the anvil roll, and a ruled line that is almost parallel to the corrugated core step is engraved on the corrugated cardboard sheet fed between the two rolls by the ruled member attached to the template. In the crease device, the thickness of the crease portion to be creased on the corrugated cardboard sheet of the crease member is about 0.7 to 3.0 mm, and the cross-sectional shape of the sheet pressing surface is arcuate or rounded on both side edges A deep groove that is flat and has a large number of notches in the length direction over the entire length of the crease at equal pitches, the depth of the notches is smaller than the thickness of the cardboard sheet, and the depth from the sheet surface is deep. A crease forming apparatus characterized in that a groove-like crease ruled line can be formed by alternately arranging a shallow groove portion and a shallow groove portion.

The receiving roll and the crease roll are rotated relatively in opposite directions, and the corrugated cardboard sheet fed between the two rolls by the ridges for crease provided on the outer periphery of the crease roll is almost at the corrugated core step. In the crease forming apparatus for forming crease lines in parallel, the ridge for the crease has a thickness of about 0.7 to 3.0 mm, and the cross-sectional shape of the outer peripheral surface into which the corrugated cardboard sheet is pushed is circular or rounded on both side edges. It is flat, and a large number of notches are formed at equal pitches along the entire length of the outer periphery of the ridge, and the depth of the notches is made smaller than the thickness of the corrugated sheet, and the depth from the sheet surface is deep. A crease forming apparatus capable of forming a groove-like crease ruled line in which a deep groove portion and a shallow groove portion having a shallow depth are alternately arranged.