Print apparatus
20 claims: 5 independent, 15 dependent
- 1両面プリントを行なうことが可能なプリント装置であって、 連続したシートを保持して供給するためのシート供給部と、 前記シート供給部からシートが供給される経路において、シートにプリントを行なうプリント部と、 前記経路において前記プリント部によるプリント位置よりも下流にて、前記プリント部の状態を認識するために前記プリント部によってシートに形成されたパターンまたは画像を読み取る第1読取部と、 前記経路において前記第1読取部による読取位置よりも下流にて、シートに形成されたカットマークを読み取る、前記第1読取部とは別に設けられた第2読取部と、 前記経路において前記第2読取部による読取位置よりも下流にて、シートを切断するカッタと、 前記カッタを通過したシートの表裏を反転させて再び前記プリント部に供給するための反転部と、 前記カッタを通過したシートを排出する排出部と、を有し、 前記両面プリントにおいては、前記シート供給部からシートが供給され、前記プリント部において第1面に複数の画像が順次プリントされ 、その後端が切断され たシートは前記反転部に導かれて表裏が反転されて再び前記プリント部に供給され、次いで、前記プリント部において前記第1面の背面側の第2面に複数の画像とともにカットマークが順次プリントされたシートは前記カッタで画像ごとに切断されて前記排出部に排出されるものであり、前記第2読取部による前記第2面の前記カットマークの読み取りに基づいて前記カッタでシートが切断されることを特徴とするプリント装置。
- 2前記反転部はシートを巻き取る巻取回転体を有し、前記両面プリントにおいては、前記第1面に複数の画像が順次プリントされたシートは前記巻取回転体に一時的に巻き取られ、その後、前記巻取回転体が逆回転して前記一時的に巻き取られたシートが再び前記プリント部に供給されて前記第2面に複数の画像が順次プリントされることを特徴とする、請求項1記載のプリント装置。
- 3前記両面プリントにおいて、 前記第1面にプリントの際には、前記プリント部により、複数の画像を順次プリントするとともに隣り合う画像の間の余白領域の少なくとも1つに前記パターンを形成し、 前記第2面へのプリントの際には、前記プリント部により、複数の画像を順次プリントするとともに、隣り合う画像の間の余白領域に前記カットマークを形成し且つ少なくとも1つの当該余白領域に前記パターンを形成することを特徴とする、請求項1または2に記載のプリント装置。
- 4前記両面プリントと片面プリントを選択的に行うことが可能であり、前記片面プリントの際には、前記プリント部により、シートが搬送される方向に沿ってシートに複数の画像を順次プリントするとともに、隣り合う画像の間の余白領域に前記カットマークを形成し且つ少なくとも1つの当該余白領域に前記パターンを形成することを特徴とする、請求項3記載のプリント装置。
- 5前記第1読取部での読み取りに基づいて前記プリント部が正常でないと判断された場合は、すでにプリント済みのシートを 前記カッタで切断して、切断されたシートの一方を 前記反転部に一時的に収容し、前記プリント部のメンテナンスが済んだ後、前記反転部から再びシートを供給してプリントを再開することを特徴とする、請求項1から4のいずれかに記載のプリント装置。
- 6前記第1読取部の読み取りにより前記プリント部が正常でないと判断された場合は、前記プリント部でカットマークを記録し、前記第2読取部で当該カットマークを読み取ってシートを切断してからプリント動作を停止することを特徴とする、請求項1から5のいずれかに記載のプリント装置。
- 7前記正常でないとの判断の後に切断したシートは前記シート供給部に送り戻し、前記プリント部のメンテナンスが済んだ後、前記シート供給部から再びシートを供給してプリントを再開することを特徴とする、請求項6記載のプリント装置。
- 8前記カッタによる切断位置の近傍でシートを搬送するためのカッタ搬送機構を有し、前記カッタ搬送機構は前記第1面へのプリントと前記第2面へのプリントとで制御方法が切り替えられることを特徴とする、請求項1から7のいずれか記載のプリント装置。
- 9前記カッタ搬送機構は、前記第1面に複数の画像を順次プリントする際には停止することなくシートを搬送し、前記第2面に複数の画像を順次プリントする際には、前記第2読取部による前記カットマークの読み取りタイミングに応じて停止を含む非一定速度でシートを搬送するように制御されることを特徴とする、請求項8記載のプリント装置。
- 10前記カッタは、シート上の第1切断位置でシートを切断するための第1カッタと、シート上の前記第1切断位置よりも下流の第2切断位置でシートを切断するための前記第1カッタよりも下流に設けられ第2カッタを備え、前記第2読取部による前記カットマークの読み取りに基づいて、先に前記第1カッタにより前記第1切断位置でシートが切断され、次いで前記第2カッタにより前記第2切断位置でシートが切断され、且つ、 前記第1切断位置は、前記カットマークおよび前記パターンの少なくとも一方が形成された余白領域の上流側の端部に対応して設定された位置であり、前記第2切断位置は前記余白領域の下流側の端部に対応して設定された位置であることを特徴とする、請求項1から9のいずれかに記載のプリント装置。
- 11前記第2読取部は、前記カットマークおよび前記パターンの少なくとも一方が形成された余白領域が前記第2読取部による読取位置を通過すると推定される検出期間に限定して前記カットマークを読み取ることを特徴とする、請求項1から10のいずれかに記載のプリント装置。
- 12前記検出期間は前記第1読取部によるシートの読み取りに基づいて設定されることを特徴とする、請求項11記載のプリント装置。
- 13同一のカットマークを前記第1読取部および前記第2読取部で検出することを特徴とする、請求項1から12のいずれかに記載のプリント装置。
- 14前記第1読取部および前記第2読取部の検出状態に基づいて、前記カットマークが検出不能となった場合の原因を判別することを特徴とする、請求項13記載のプリント装置。
- 15前記プリント部は、複数色に対応した複数のインクジェット方式のライン型プリントヘッドを備え、前記パターンは複数のプリントヘッドによって形成した不吐検出用のパターンであることを特徴とする、請求項1から14いずれかに記載のプリント装置。
- 16前記第1読取部は使用するシートの幅をカバーする範囲を読取可能であるライン型またはエリア型のイメージセンサを有し、前記第2読取部は前記イメージセンサよりも読取領域が狭いセンサを有することを特徴とする、請求項1から15のいずれかに記載のプリント装置。
- 17連続したシートが供給される経路においてシートにプリントを行なうプリント部と、 前記経路において前記プリント部によるプリント位置よりも下流にて、前記プリント部の状態を認識するために前記プリント部によってシートに形成されたパターンまたは画像を読み取る第1読取部と、 前記経路において前記第1読取部による読取位置よりも下流にて、シートに形成されたカットマークを読み取る、前記第1読取部とは別に設けられた第2読取部と、 前記経路において前記第2読取部による読取位置よりも下流にて、シート上の第1切断位置でシートを切断するための第1カッタと、 前記第1切断位置よりも下流の第2切断位置でシートを切断するための前記第1カッタよりも下流に設けられ た 第2カッタと、を有し、 前記プリント部によって、シートが搬送される方向に沿ってシートに複数の画像が順次プリントされるとともに、隣り合う画像の間の余白領域に前記カットマークが形成され且つ少なくとも1つの当該余白領域に前記パターンが形成されるものであり、 前記第1切断位置は前記余白領域の上流側の端部に対応して設定された位置であり、前記第2切断位置は前記余白領域の下流側の端部に対応して設定された位置であり、前記第2読取部による前記カットマークの読み取りに基づいて先に前記第1カッタにより前記第1切断位置でシートが切断され、次いで前記第2カッタにより前記第2切断位置でシートが切断されることを特徴とするプリント装置。
- 18前記第1読取部による前記パターンの読み取りに基づいて前記プリント部が正常でないと判断された場合は、前記プリント部で前記カットマークを記録し、前記第2読取部で当該カットマークを読み取ってシートを切断してからプリント動作を停止することを特徴とする、請求項16記載のプリント装置。
- 19連続したシートが供給される経路においてシートにプリントを行なうプリント部と、 前記経路において前記プリント部によるプリント位置よりも下流にて、前記プリント部の状態を認識するために前記プリント部によってシートに形成されたパターンまたは画像を読み取る第1読取部と、 前記経路において前記第1読取部による読取位置よりも下流にて、シートに形成されたカットマークを読み取る、前記第1読取部とは別に設けられた第2読取部と、 前記経路において前記第2読取部による読取位置よりも下流にて、シートを切断するためのカッタと、を有し、 前記プリント部によって、シートが搬送される方向に沿ってシートに複数の画像が順次プリントされるとともに、隣り合う画像の間の余白領域に前記カットマークが形成され且つ少なくとも1つの当該余白領域に前記パターンが形成されるものであり、 前記第2読取部は前記余白領域が前記第2読取部による読取位置を通過すると推定される検出期間に限定して前記カットマークを読み取り、前記第2読取部による前記カットマークの読み取りに基づいて前記カッタでシートが切断される ものであり、前記検出期間は前記第1読取部によるシートの読み取りに基づいて設定される ことを特徴とするプリント装置。
- 20連続したシートが供給される経路においてシートにプリントを行なうプリント部と、 前記経路において前記プリント部によるプリント位置よりも下流にて、前記プリント部の状態を認識するために前記プリント部によってシートに形成されたパターンまたは画像を読み取る第1読取部と、 前記経路において前記第1読取部による読取位置よりも下流にて、シートに形成されたカットマークを読み取る、前記第1読取部とは別に設けられた第2読取部と、 前記経路において前記第2読取部による読取位置よりも下流にて、シートを切断するためのカッタと、を有し、 前記プリント部によって、シートが搬送される方向に沿ってシートに複数の画像が順次プリントされるとともに、隣り合う画像の間の余白領域に前記カットマークが形成され且つ少なくとも1つの当該余白領域に前記パターンが形成されるものであり、 前記第2読取部は前記余白領域が前記第2読取部による読取位置を通過すると推定される検出期間に限定して前記カットマークを読み取り、前記第2読取部による前記カットマークの読み取りに基づいて前記カッタでシートが切断されるものであり、 前記第1読取部による前記パターンの読み取り に 基づいて前記プリント部の状態が認識され、前記プリント部が正常でないと判断された場合は、前記プリント部で前記カットマークを記録し、前記第2読取部で当該カットマークを読み取ってシートを切断してからプリント動作を停止することを特徴とす る プリント装置。
Independent claims20
63 paragraphs, as filed
The present invention relates to a printing apparatus using continuous sheets.
Patent Document 1 discloses a printing apparatus that sequentially prints a plurality of images on a continuous sheet. In this printing apparatus, a density sensor (35) for measuring the ink density of an image is provided downstream of the print head (H), a cut position sensor (41), and a cutter (40) are provided downstream thereof. A print head is used to record a cutter mark in a margin area between adjacent images together with a plurality of images, and a sheet is cut for each image based on the cut mark detection by the cut mark sensor. In this way, the final printed matter cut for each image is generated.
<p><patcit num="1"><text>Japanese Patent Application Laid-Open No. 2005-305712</text></patcit></p>
<p> In fields such as photo album binding, it is desired that a single printing device prints on both sides of a continuous sheet at high speed and with high quality. When bundling and binding a plurality of double-sided printed sheets, it is necessary that the sizes of the sheets are exactly the same. However, the apparatus described in Patent Document 1 only assumes printing on one side of a sheet. Therefore, the first object of the present invention is how to print on both sides at high speed and with high quality and cut each sheet with high position accuracy to produce a final printed matter.</p><p> Further, in the apparatus described in Patent Document 1, when cutting a sheet with a cutter, it is necessary to temporarily stop the transfer of the sheet at the cutting position. Then, a slight impact caused by stopping the sheet is transmitted to the upstream side of the sheet, causing the sheet to be slightly displaced, which may affect the reading accuracy of the density sensor and the printing accuracy of the print head. When a margin area is provided between adjacent images as in Patent Document 1, the margin area becomes unnecessary after the cut mark is detected, so the margin area is cut off with a cutter. In order to cut off the margin area, the sheet is stopped twice in succession because it is cut twice in succession at the front end and the rear end of the margin area. For this reason, the two impacts are transmitted to the upstream side of the sheet, which has a considerable effect on the reading accuracy of the density sensor and the printing accuracy of the print head. The second object of the present invention is how to reduce this influence.</p><p> Further, in the apparatus described in Patent Document 1, when the cut position sensor detects the cut mark sheet, the cut position sensor needs to distinguish between the original image and the cut mark and correctly detect only the cut mark. .. However, if a pattern similar to the cut mark is accidentally included in the original image, there is a fear that it will be mistaken for the cut mark and the sheet will be cut at the wrong position. The third object of the present invention is how to reduce such misunderstandings.</p>
<p> The printing apparatus of the present invention of the first aspect is a printing apparatus capable of performing double-sided printing, and is a sheet supply unit for holding and supplying continuous sheets, and a sheet is supplied from the sheet supply unit. In the path to be printed, a printed portion that prints on the sheet, and a pattern formed on the sheet by the printed portion in order to recognize the state of the printed portion downstream from the printing position by the printed portion in the route. A second reading unit provided separately from the first reading unit that reads an image and a cut mark formed on the sheet downstream of the reading position by the first reading unit in the path. A cutter for cutting the sheet and a reversing section for reversing the front and back of the sheet that has passed through the cutter and supplying the printed portion again downstream from the reading position by the second reading section in the path. A sheet is supplied from the sheet supply unit in the double-sided printing, and a plurality of images are sequentially printed on the first surface of the printing unit.<u style="single">, The trailing edge is cut off</u>The sheet is guided to the reversing part, the front and back sides are reversed, and the sheet is supplied to the printing part again. Then, the cut mark is sequentially printed together with a plurality of images on the second side on the back side of the first side in the printing part. The cut sheet is cut by the cutter for each image and discharged to the discharging unit, and the sheet is cut by the cutter based on the reading of the cut mark on the second surface by the second reading unit. It is characterized by that.</p><p> In the printing apparatus of the present invention of the second aspect, the state of the printing unit that prints on the sheet in the path where the continuous sheet is supplied and the state of the printing unit in the path downstream of the printing position by the printing unit. The first reading unit that reads the pattern or image formed on the sheet by the printing unit and the cut mark formed on the sheet downstream from the reading position by the first reading unit in the path are used. A second reading unit provided separately from the first reading unit for reading, and a second reading unit for cutting the sheet at the first cutting position on the sheet downstream of the reading position by the second reading unit in the path. It is provided downstream from the first cutter and the first cutter for cutting the sheet at the second cutting position downstream of the first cutting position.<u style="single">Ta</u>A second cutter is provided, and a plurality of images are sequentially printed on the sheet along the direction in which the sheet is conveyed by the printing portion, and the cut mark is formed in a margin area between adjacent images. Moreover, the pattern is formed in at least one of the margin regions, the first cutting position is a position set corresponding to the upstream end of the margin region, and the second cutting position is The position is set corresponding to the downstream end of the margin region, and the sheet is first cut at the first cutting position by the first cutter based on the reading of the cut mark by the second reading unit. Then, the sheet is cut at the second cutting position by the second cutter.</p><p> In the printing apparatus of the present invention of the third aspect, the state of the printed portion that prints on the sheet in the path where the continuous sheet is supplied and the state of the printed portion in the path downstream of the printing position by the printed portion. A first reading unit that reads a pattern or an image formed on the sheet by the printing unit and a cut mark formed on the sheet downstream of the reading position by the first reading unit in the path. It has a second reading unit provided separately from the first reading unit for reading, and a cutter for cutting the sheet downstream of the reading position by the second reading unit in the path. The printing unit sequentially prints a plurality of images on the sheet along the direction in which the sheet is conveyed, the cut mark is formed in the margin area between adjacent images, and the pattern is formed in at least one of the margin areas. Is formed, the second reading unit reads the cut mark only during the detection period in which the margin area is estimated to pass the reading position by the second reading unit, and the second reading unit reads the cut mark. The sheet is cut by the cutter based on the reading of the cut mark.<u style="single">The detection period is set based on the reading of the sheet by the first reading unit.</u>。 </p>
<p> According to the present invention of the first aspect, it is possible to print at high speed and high quality in double-sided printing and to cut a sheet one by one with high position accuracy to obtain a final printed matter.</p><p> According to the second aspect of the present invention, the impact on the upstream sheet due to the cutter cutting the sheet twice is only once, which gives the reading accuracy and the printing accuracy of the first reading unit. The impact can be mitigated. As a result, a printed matter having high print quality can be obtained.</p><p> According to the third aspect of the present invention, there is almost no possibility that the cut mark sensor mistakenly recognizes the original image as a cut mark, so that the situation where the sheet is cut at the wrong position can be avoided.</p>
<figref num="1">Schematic diagram showing the internal configuration of the printing apparatus</figref><figref num="2">Block diagram of the control unit</figref><figref num="3">Diagram for explaining operation in single-sided print mode and double-sided print mode</figref><figref num="4">The figure which shows the arrangement of a plurality of images which are sequentially printed on a sheet</figref><figref num="5">The figure which shows the state which the cut mark is detected</figref><figref num="6">The figure for demonstrating the operation which detects a cut mark and cuts a sheet.</figref><figref num="7">Flowchart showing the processing procedure of inspection pattern analysis</figref><figref num="8">Diagram for explaining the judgment of discharge / non-discharge</figref><figref num="9">Flowchart showing the processing sequence when an abnormality of the print head is detected</figref><figref num="10">Diagram to illustrate the rationality of the device layout</figref>
Hereinafter, embodiments of a printing apparatus using an inkjet method will be described. The printing device of this example uses a long continuous sheet (a continuous sheet longer than the length of a repeating printing unit (called one page or unit image) in the transport direction) for both single-sided printing and double-sided printing. It is a compatible high-speed line printer. For example, it is suitable for the field of printing a large number of sheets in a print lab or the like. In this specification, even if a plurality of small images, characters, and blanks are mixed in one print unit (one page) area, those contained in the area are collectively referred to as one unit image. .. That is, the unit image means one print unit (one page) when a plurality of pages are sequentially printed on consecutive sheets. In addition, it may be simply an image rather than a unit image. The length of the unit image varies depending on the image size to be printed. For example, in the L size photograph, the length in the sheet transport direction is 135 mm, and in the A4 size, the length in the sheet transport direction is 297 mm.
The present invention can be widely applied to printing devices such as printers, printer multifunction devices, copiers, facsimile machines, and manufacturing devices for various devices. The printing process may be an inkjet method, an electrophotographic method, a thermal transfer method, a dot impact method, a liquid development method, or the like. Further, the present invention is applicable not only to a printing process but also to a sheet processing apparatus that performs various processes (recording, processing, coating, irradiation, reading, inspection, etc.) on a roll sheet.
FIG. 1 is a schematic cross-sectional view showing the internal configuration of the printing apparatus. In the printing apparatus of this embodiment, it is possible to print on both sides of the first surface of the sheet and the second surface on the back side of the first surface by using the sheet wound in a roll shape. Inside the printing device, there are roughly 1 sheet supply section, 2 decal section, 3 skew correction section, 4 printing section, 5 inspection section, 6 cutter section, 7 information recording section, 8 drying section, 9 reversing section, and discharging. Each unit includes a transport unit 10, a sorter unit 11, a discharge unit 12, and a control unit 13. The sheet is transported by a transport mechanism consisting of a pair of rollers and a belt along the sheet transport path shown by the solid line in the figure, and is processed by each unit. At an arbitrary position on the sheet transport path, the side closer to the sheet supply unit 1 is referred to as "upstream", and the opposite side is referred to as "downstream".
The sheet supply unit 1 is a unit for holding and supplying a continuous sheet wound in a roll shape. The sheet supply unit 1 can store two rolls R1 and R2, and has a configuration in which the sheet is selectively pulled out and supplied. The number of rolls that can be stored is not limited to two, and one or three or more rolls may be stored. Further, if it is a continuous sheet, it is not limited to a roll-shaped sheet. For example, a continuous sheet to which perforations are added for each unit length may be folded and laminated for each perforation and stored in the sheet supply unit 1.
The decal unit 2 is a unit that reduces the curl (warp) of the sheet supplied from the sheet supply unit 1. In the decal portion 2, two pinch rollers are used for one drive roller, and the sheet is curved and passed so as to give the curl in the opposite direction, so that the decal force is applied to reduce the curl.
The skew correction unit 3 is a unit that corrects the skew (inclination with respect to the original traveling direction) of the sheet that has passed through the decal portion 2. By pressing the end of the seat on the reference side against the guide member, the skew of the seat is corrected.
The print unit 4 is a sheet processing unit that forms an image by performing a print process on the sheet to be conveyed by the print head 14 from above. That is, the print unit 4 is a processing unit that performs a predetermined process on the sheet. The print unit 4 also includes a plurality of transport rollers for transporting the sheet. The print head 14 has a line-type print head in which an inkjet nozzle row is formed within a range that covers the maximum width of a sheet that is expected to be used. In the print head 14, a plurality of print heads are arranged in parallel along the transport direction. This example has seven printheads that support seven colors: C (cyan), M (magenta), Y (yellow), LC (light cyan), LM (light magenta), G (gray), and K (black). .. The number of colors and the number of printheads are not limited to seven. As the inkjet method, a method using a heat generating element, a method using a piezo element, a method using an electrostatic element, a method using a MEMS element, or the like can be adopted. The ink of each color is supplied from the ink tank to the print head 14 via the ink tube.
The inspection unit 5 optically reads the inspection pattern or image printed on the sheet by the printing unit 4 with a scanner, inspects the nozzle state of the print head, the sheet transport state, the image position, etc., and prints the image correctly. It is a unit for judging whether or not it is. The scanner has a line-type or area-type image sensor (CCD image sensor or CMOS image sensor) that can read a range covering the width of the sheet to be used. The image sensor is sensitive to multiple colors used in the inspection pattern, that is, seven ink colors. The inspection unit 5 functions as a first reading unit that reads the inspection pattern formed on the sheet on the downstream side of the print position by the print head 14 in the transport path.
The cutter portion 6 is a unit having a cutter 20 that cuts a printed sheet to a predetermined length. The cutter 20 consists of two mechanical cutters 20a and 20b. The cutter 20a on the upstream side and the cutter 20b on the downstream side efficiently cut off the margin area between the images formed on the sheet, as will be described later. The cutter unit 6 also includes a cut mark sensor 19 that optically detects the cut mark recorded on the sheet, and a plurality of transfer rollers for feeding the sheet to the next process. The cut mark sensor 19 has a narrower reading area than the image sensor of the inspection unit 5. The optical sensor constituting the cut mark sensor 19 is at least sensitive to the color used for the cut mark. The cut mark sensor 19 functions as a second reading unit that reads the cut mark formed on the sheet on the downstream side of the reading position by the inspection unit 5 (first reading unit) in the transport path. A trash can 17 is provided in the vicinity of the cutter portion 6. The trash can 17 accommodates a small sheet piece whose margin area is cut off by the cutters 20a and 20b and discharged as garbage. The cutter portion 6 is provided with a sorting mechanism for discharging the cut sheet to the trash can 17 or shifting to the original transport path.
The information recording unit 7 is a unit that records print information (unique information) such as a print serial number and date in a non-print area of a cut sheet. Recording is performed by printing characters and codes by an inkjet method, a thermal transfer method, or the like. An edge sensor 21 for detecting the tip edge of the cut sheet is provided on the upstream side of the information recording unit 7 and the downstream side of the cutter unit 6. That is, the edge sensor 21 detects the edge of the sheet between the cutter unit 6 and the recording position by the information recording unit 7, and the timing of information recording by the information recording unit 7 is controlled based on the detection timing of the edge sensor 21. To.
The drying unit 8 is a unit for heating the sheet printed by the printing unit 4 to dry the applied ink in a short time. Inside the drying portion 8, hot air is applied to the passing sheet from at least the lower surface side to dry the ink-applied surface. The drying method is not limited to the method of applying hot air, and may be a method of irradiating the sheet surface with electromagnetic waves (ultraviolet rays, infrared rays, etc.).
The above sheet transport path from the sheet supply section 1 to the drying section 8 is referred to as a first path. The first path has a U-turn shape between the printed portion 4 and the drying portion 8, and the cutter portion 6 is located in the middle of the U-turn shape.
The reversing unit 9 is a unit for temporarily winding and accommodating a continuous sheet whose front surface printing has been completed when performing double-sided printing, and inverting the front and back sides. The reversing section 9 is a path (loop path) (referred to as a second path) from the drying section 8 to the printing section 4 via the decal section 2 for supplying the sheet that has passed through the drying section 8 to the printing section 4 again. It is provided on the way. The reversing portion 9 includes a rotating winding body (drum) for winding the sheet. The continuous sheet, whose surface has been printed and has not been cut, is accommodated by being temporarily wound by a winding body. When the winding is completed, the winding rotating body rotates in the reverse direction, and the wound sheet is sent out in the reverse order of the winding, supplied to the decal section 2, and sent to the printing section 4. Since this sheet is turned upside down, the printing unit 4 can print on the back side. A more specific operation of double-sided printing will be described later.
The discharge transport unit 10 is a unit for transporting a sheet cut by the cutter unit 6 and dried by the drying unit 8 and delivering the sheet to the sorter unit 11. The discharge transport unit 10 is provided in a route (referred to as a third route) different from the second route in which the reversing unit 9 is provided. In order to selectively guide the sheet conveyed on the first route to either the second route or the third route, a route switching mechanism having a movable flapper is provided at the branch position of the route.
The sorter portion 11 and the discharge portion 12 are provided on the side portion of the sheet supply portion 1 and at the end of the third path. The sorter unit 11 is a unit for sorting printed sheets into groups as needed. The sorted sheets are discharged to the discharge unit 12 composed of a plurality of trays. In this way, the third path passes below the sheet supply unit 1 and has a layout in which the sheet is discharged to the opposite side of the print unit 4 and the drying unit 8 with the sheet supply unit 1 in between.
As described above, the sheet supply section 1 to the drying section 8 are provided in order in the first path. The tip of the drying section 8 is branched into a second path and a third path, a reversing section 9 is provided in the middle of the second path, and the tip of the reversing section 9 joins the first path. A discharge section 12 is provided at the end of the third path.
The control unit 13 is a unit that controls each part of the entire printing apparatus. The control unit 13 includes a CPU, a storage device, a controller including various control units, an external interface, and an operation unit 15 for input / output by the user. The operation of the printing device is controlled based on a command from a host device 16 such as a host computer connected to the controller or the controller via an external interface.
A mark reader 18 is provided between the skew correction section 3 and the print section 4. The mark reader 18 is a reflective optical sensor that optically reads the reference mark recorded on the first surface of the sheet conveyed from the reversing portion 9 from the side opposite to the printing side. The mark reader 18 has a light source (for example, a white LED) that illuminates the sheet surface, and a receiver such as a photodiode or an image sensor that detects the light from the illuminated sheet surface for each RGB component. The mark can be read by changing the signal level of the receiver or by image analysis of the imaging data.
FIG. 2 is a block diagram showing the concept of the control unit 13. The controller (range surrounded by a broken line) included in the control unit 13 is composed of a CPU 201, a ROM 202, a RAM 203, an HDD 204, an image processing unit 207, an engine control unit 208, and an individual unit control unit 209. CPU201 (central arithmetic processing unit) controls the operation of each unit of the printing apparatus in an integrated manner. The ROM 202 stores fixed data necessary for various operations of the program and the printing device to be executed by the CPU 201. The RAM 203 is used as a work area of the CPU 201, is used as a temporary storage area for various received data, and stores various setting data. The HDD 204 (hard disk) can store and read programs for execution by the CPU 201, print data, and setting information necessary for various operations of the printing device. The operation unit 15 is an input / output interface with the user, and includes an input unit of a hard key or a touch panel, and an output unit such as a display or a voice generator that presents information.
A dedicated processing unit is provided for units that require high-speed data processing. The image processing unit 207 performs image processing of the print data handled by the printing apparatus. Converts the color space of the input image data (eg YCbCr) to a standard RGB color space (eg sRGB). In addition, various image processes such as resolution conversion, image analysis, and image correction are performed on the image data as needed. The print data obtained by these image processing is stored in RAM 203 or HDD 204. The engine control unit 208 controls the drive of the print head 14 of the print unit 4 according to the print data based on the control command received from the CPU 201 or the like. The engine control unit 208 also controls the transport mechanism of each part in the printing device. The individual unit control unit 209 includes a sheet supply unit 1, a decal unit 2, a skew correction unit 3, an inspection unit 5, a cutter unit 6, an information recording unit 7, a drying unit 8, a reversing unit 9, a discharge transport unit 10, and a sorter unit. 11. It is a sub controller for individually controlling each unit of the discharge unit 12. The operation of each unit is controlled by the individual unit control unit 209 based on the command from the CPU 201. The external interface 205 is an interface (I / F) for connecting the controller to the host device 16, and is a local I / F or a network I / F. The above components are connected by the system bus 210.
The host device 16 is a device that serves as a source of image data for causing the printing device to perform printing. The host device 16 may be a general-purpose or dedicated computer, or may be a dedicated image device such as an image capture, a digital camera, or a photo storage having an image reader unit. When the host device 16 is a computer, the OS, application software for generating image data, and a printer driver for the printing device are installed in the storage device included in the computer. It is not essential that all of the above processes are realized by software, and some or all of them may be realized by hardware.
Next, the basic operation at the time of printing will be described. Since the operation of printing differs between the single-sided printing mode and the double-sided printing mode, each of them will be described.
FIG. 3A is a diagram for explaining the operation in the single-sided print mode. The surface (first surface) of the sheet supplied from the sheet supply unit 1 and processed by the decal unit 2 and the skew correction unit 3 is printed on the print unit 4. Images (unit images) having a predetermined unit length in the transport direction are sequentially printed on a long continuous sheet to form a plurality of images side by side. Here, a margin area is provided between one image and the next image, and a cut mark is recorded in the margin area by the print unit 4. The printed sheet passes through the inspection unit 5 and is cut by the cutter 20 for each unit image based on the cut mark detection by the cut mark sensor 19 in the cutter unit 6. For the cut cut sheet, print information is recorded on the back surface of the sheet by the information recording unit 7 as needed. Then, the cut sheets are conveyed to the drying unit 8 one by one and dried. After that, it is sequentially discharged and loaded in the discharge section 12 of the sorter section 11 via the discharge transport section 10. On the other hand, the sheet left on the side of the print unit 4 by cutting the final unit image is sent back to the sheet supply unit 1, and the sheet is wound up on the roll R1 or R2.
As described above, in the single-sided printing, the sheet is processed through the first path and the third path, and does not pass through the second path. Summarizing the above, in the single-sided print mode, the following sequences (1) to (6) are executed under the control of the control unit 13. (1) The sheet is sent out from the sheet supply unit 1 and supplied to the print unit 4; (2) Repeat the printing of the unit image and the cut mark on the first side of the supplied sheet with the printing part 4; (3) Repeat cutting the sheet at the cutter part 6 for each unit image printed on the first side; (4) Pass the sheets cut for each unit image one by one through the drying section 8; (5) The sheets that have passed through the drying section 8 one by one are discharged to the discharging section 12 through the third path; (6) The last unit image is cut and the sheet left on the side of the print unit 4 is sent back to the sheet supply unit 1.
FIG. 3B is a diagram for explaining the operation in the double-sided print mode. In double-sided printing, the front side (first side) print sequence is followed by the back side (second side) print sequence. In the first surface printing sequence, the operation of each unit from the sheet supply unit 1 to the inspection unit 5 is the same as the operation of the single-sided printing described above. The cutter portion 6 does not perform a cutting operation, and is conveyed to the drying portion 8 as a continuous sheet. After the surface ink is dried in the drying section 8, the sheet is guided not to the path on the side of the discharge transport section 10 (third path) but to the path on the side of the reversing section 9 (second path). In the second path, the sheet is wound by the winding rotating body of the reversing portion 9 that rotates in the forward direction (counterclockwise in the drawing). When all the planned surface printing is completed in the print portion 4, the rear end of the print area of the continuous sheet is cut by the cutter portion 6. Based on the cutting position, the continuous sheet on the downstream side (printed side) in the transport direction is completely wound up to the rear end (cutting position) of the sheet by the reversing portion 9 through the drying portion 8. On the other hand, at the same time as this winding, the continuous sheet left on the upstream side in the transport direction (the side of the printed portion 4) from the cutting position has a sheet supply unit so that the sheet tip (cutting position) does not remain on the decal portion 2. Rewound to 1 and the sheet is wound onto rolls R1 or R2. This rewinding avoids collisions with the sheets that are resupplied in the backside print sequence below.
After the front side print sequence described above, the back side print sequence is switched to. The winding rotating body of the reversing part 9 rotates in the direction opposite to that at the time of winding (clockwise in the drawing). The end of the wound sheet (the rear end of the sheet at the time of winding becomes the tip of the sheet at the time of feeding) is fed to the decal portion 2 along the path of the broken line in the figure. In the decal portion 2, the curl given by the winding rotating body is corrected. That is, the decal section 2 is provided between the sheet supply section 1 and the print section 4 in the first path, and between the inversion section 9 and the print section 4 in the second path, and acts as a decal in any of the paths. It is a common unit. The sheet whose front and back sides are reversed is sent to the printing unit 4 via the skew correction unit 3, and the unit image and the cut mark are printed on the back surface of the sheet. The printed sheet passes through the inspection unit 5 and is cut into the cutter unit 6 at predetermined unit lengths set in advance. Since the cut sheet is printed on both sides, it is not recorded by the information recording unit 7. The cut sheets are conveyed to the drying section 8 one by one, and are sequentially discharged and loaded in the discharging section 12 of the sorter section 11 via the discharging transport section 10.
As described above, in double-sided printing, the sheet is processed by passing through the first path, the second path, the first path, and the third path in this order. Summarizing the above, in the double-sided print mode, the following sequences (1) to (11) are executed under the control of the control unit 13. (1) The sheet is sent out from the sheet supply unit 1 and supplied to the print unit 4; (2) Repeat the printing of the unit image on the first side of the supplied sheet with the print unit 4; (3) Pass the sheet printed on the first surface through the drying section 8; (4) The sheet that has passed through the drying portion 8 is guided to the second path and wound around the winding rotating body of the reversing portion 9; (5) After repeated printing on the first side, cut the sheet at the cutter part 6 behind the last printed unit image; (6) The cut sheet is wound around the winding rotating body until the end portion of the cut sheet passes through the drying portion 8 and reaches the winding rotating body. At the same time, the sheet cut and left on the side of the print section 4 is sent back to the sheet supply section 1; (7) When the winding is completed, the winding rotating body is rotated in the reverse direction, and the sheet is supplied to the printed portion 4 again from the second path; (8) Repeat the printing of the unit image and the cut mark on the second surface of the sheet supplied from the second path by the printing unit 4; (9) Repeat cutting the sheet at the cutter part 6 for each unit image printed on the second side; (10) Pass the sheets cut for each unit image one by one through the drying section 8; (11) The sheets that have passed through the drying section 8 one by one are discharged to the discharging section 12 through the third path.
As described above, in the back side printing in the single-sided printing mode and the double-sided printing mode, a cut mark is recorded together with the printing of the unit image, and the sheet is cut by the cutter portion 6 based on the detection of the cut mark.
FIG. 4 shows some examples of an array of a plurality of images (image 1, image 2, image 3, ...) Printed sequentially on a sheet. In FIG. 4 (a), the image area 100 (100-1, 100-2, 100-3, ...) And the non-image area margin area 101 (101-1, 101-2, 101-3, ...) ...) are lined up alternately. Cut marks 102 (102-1, 102-2, 102-3, ...) Are formed in each of the margin areas 101. FIG. 4B shows an example of an arrangement in which the inspection pattern 103 for printhead maintenance is assigned to the margin area 101 together with the cut mark 102. As will be described later, the inspection pattern 103 is a pattern for detecting ejection failure formed by a plurality of nozzles, and is read and analyzed by the inspection unit 5 in order to determine the state of the print head. Each margin area 101 (101-1, 101-2, 101-3, ...) Is the area where the cut mark 102 (102-1, 102-2, 102-3, ...) Is formed. , The region where the inspection pattern 103 is formed is combined. In this example, the size of the unit images (image 1, image 2, ...) In the transport direction is larger than that of FIG. 4 (a). FIG. 4 (c) shows an example of an arrangement in which the inspection pattern 103 for printhead maintenance is formed only in a part of the margin area. That is, the cut mark is formed more frequently in the margin region than the inspection pattern. The size of the margin area in the transport direction is different between the margin area (101-1, 101-2) including the inspection pattern 103 and the margin area (103-3) not including the inspection pattern 103.
FIG. 5 is a diagram showing a state in which the cut mark is detected by the cut mark sensor 19. The cut mark sensor 19 is a small optical sensor having a light source and a light receiving element. For example, the cut mark 102 is a rectangular mark of 2x2 [mm], and the spot diameter of the illumination light 110 illuminated on the cut mark 102 is φ1 [mm]. A small semiconductor light source (LED, OLED, semiconductor laser, etc.) is suitable as the light source. For example, the light source is a red LED, and the cut mark 102 is recorded with black ink having a good absorption distribution characteristic with respect to red. In the sheet transport direction, the margin region 101 has a width of a predetermined length M (4 mm). Also, in order to facilitate the distinction between the image area 100 and the cut mark 102, the length between the previous image area 100- (n-1) and the cut mark 102-n is half the length M. A blank (white area) of 2 [mm]) is formed. However, it is not essential to provide such a blank.
The graph at the bottom of FIG. 5 shows the change in the detection output of the light receiving element of the cut mark sensor 19. As the sheet moves, the margin region 101 passes through the spot of the illumination light (detection position) of the sensor. At this time, as shown in Graph 120, the signal level of the detection output suddenly changes from high (white part with high reflectance) to low (black part with low reflectance). The degree of change (slope of the graph) is determined by the spot diameter of the illumination light 110. The position corresponding to the timing when the changing signal level falls below a preset predetermined threshold value is detected as the mark position. Then, based on the detected mark position, the sheet cutting position (cutting position 1 and cutting position 2 on the sheet) by the cutter is set at two places before and after the mark position. In the sheet transport direction, the distance between the cutting position 1 and the cutting position 2 is equal to or slightly larger than the length M of the margin region 101.
The cut mark is detected by the cut mark sensor 19 not constantly during the printing operation, but a detection period in which the margin area of the sheet is estimated to pass the detection position of the cut mark sensor 19 is set. The cut mark sensor 19 reads the cut mark only during this detection period. The detection period can be obtained by calculating the estimation based on the sheet transport distance from the print head that records the cut mark to the cut mark sensor 19 and the layout of the image. As a result, since the cut mark sensor 19 does not read the original printed image, it is possible to prevent the printed image from being mistakenly recognized as a cut mark.
Here, if the position of the printed image is displaced, the position of the margin area (image layout) will be different from the original one. Further, when the print head 14 is replaced, the distance (sheet transport distance) from the print head 14 to the cut mark sensor 19 may change due to a mechanical mounting tolerance. Therefore, in order to reduce these effects and further improve the accuracy of estimation, the inspection unit 5 may detect the image or the margin area, and the detection period of the cut mark sensor 19 may be set based on the detection period. .. If the estimation accuracy is improved, the cut mark can be reliably captured by the cut mark sensor 19 even if the width of the margin area (sheet transport direction) is narrowed, so that the sheet piece in the margin area, that is, the amount of dust generated and the sheet Waste can be reduced.
FIG. 6 is a diagram for explaining an operation of detecting a cut mark by the cut mark sensor 19 and cutting the sheet. When the cut mark 102 is detected, the mark position is determined. The first cutting position (cutting position 1) and the second cutting position (cutting position 2) are set before and after (upstream and downstream) of this mark position. The first cutting position is set upstream of the second cutting position with respect to the direction in which the sheet is conveyed during printing (state in FIG. 7 (1)). That is, the first cutting position is a position set corresponding to the upstream end of the margin area, and the second cutting position is a position set corresponding to the downstream end of the margin area.
When the sheet is conveyed after the cut mark is detected, the first cutting position of the sheet first passes through the cutting position of the first cutter 20a, and then the cutting position of the second cutter 20b is passed through the second cutting position of the sheet. The distance relationship is such that the position passes through. The spot of the illumination light 110 is the detection position of the cut mark sensor 19. The cutting position of the first cutter 20a is on the downstream side by a distance C1 from this detection position, and the cutting position of the second cutter 20b is on the downstream side by a distance C2 (C2> C1) from the detection position. The above-mentioned distance relationship is that the distance between the cutting position 1 and the cutting position 2 (equal to the length M of the margin area 101 or slightly larger than the length M) is smaller than the difference between the distance C2 and the distance C1. To realize. While transporting the sheet, the first cutter 20a first cuts the first cutting position (state in FIG. 7 (2)). Next, the second cutting position is cut with the second cutter 20b (state in FIG. 7 (3)).
Here, the meaning of leading the cutting at the first cutting position on the upstream side to the cutting at the second cutting position on the downstream side will be described. When the sheet is cut with the cutter 20, the sheet is temporarily stopped due to the sheet cutting operation, so the impact is transmitted to the upstream side of the sheet and may affect the reading accuracy of the inspection unit 5 and the printing accuracy of the printing unit 4. There is sex. By cutting at the first cutting position (first cutter 20a) on the upstream side first, the effect is only once. This is because, when cutting at the subsequent second cutting position (second cutter 20b), the sheet to be cut is already separated from the sheet on the upstream side and no force is transmitted. If the second cutting position is cut in advance, the above effect will occur twice, and the effect on inspection and printing will be large. If one cutter 20 is used and the same cutter is used for two consecutive cuts, the upstream of the sheet will be affected twice. Therefore, it is necessary to provide two cutters in order to precede the upstream side by cutting the sheet twice.
Next, an analysis processing procedure for reading and inspecting the inspection pattern formed in the margin region as shown in FIG. 4 (b) or FIG. 4 (c) by the inspection unit 5 will be described. As for the inspection pattern, an inspection pattern is formed in the margin area shown in FIG. 4 (b) or FIG. 4 (c) with one color of ink per one margin area, or an inspection pattern is formed with multiple colors of ink in one margin area. To form. Ink is ejected from all nozzles of printheads of all colors to form an inspection pattern using a plurality of margin areas. The inspection unit 5 reads and analyzes this inspection pattern, and determines whether the state of the nozzle of the print head 14 is normal or not (abnormal). As described above, the image sensor of the inspection unit 5 is sensitive to a plurality of colors, that is, seven ink colors used in the inspection pattern.
FIG. 7 is a flowchart showing the processing procedure of the inspection pattern analysis. The following processing is performed by the processing unit built in the inspection unit 5 or by the control unit 13 of the printing apparatus. In step S11, the RGB layer corresponding to the print color is selected. In step S12, the alignment mark included in the inspection pattern is recognized. In step S13, the area to be inspected is cut out based on the recognized position of the alignment mark. In step S14, the density of the pattern in the inspection target area is analyzed. In step S15, the concentration acquired in step S14 is averaged in the X direction to obtain the maximum value, which is compared with the threshold value. In step S16, the ejection failure nozzle is determined according to the comparison result of step S15. As shown in FIG. 8, when the average concentration exceeds the threshold value, it is judged as discharge, and when it falls below the threshold value, it is judged as non-discharge (non-discharge nozzle). In step S17, it is determined whether the printhead condition is normal or abnormal. The number of ejection failure nozzles of each print head is counted, and it is continuously monitored whether or not a predetermined tolerance is exceeded. If the permissible value is not exceeded, the print head is judged to be normal, and if the permissible value is exceeded, the print head is judged to be abnormal (abnormal). The permissible value is determined based on the printing conditions such as the number of nozzles of the print head and the colorant. The causes of abnormalities in the print head are problems with the print head 14 (non-ejection due to nozzle clogging, failure of the head itself such as elements and disconnections), and ink supply to the print head 14 due to ink shortage or ink supply system trouble. There is a shortage.
FIG. 9 is a flowchart showing a processing sequence when an abnormality of the print head is detected in the analysis of the inspection pattern. The following processing is performed by the control unit 13 of the printing apparatus. Here, it is assumed that an abnormality is detected during printing on the first side in the single-sided print mode or while printing on the second side in the back side print in the double-sided print mode. As described above, in these modes, the inspection pattern is formed in all the margin areas as shown in FIG. 4 (b) or in a part of the margin areas as shown in FIG. 4 (c). The cut mark is formed in all the margin areas.
The sequence starts when a printhead error is detected. In step S21, the last (Mth) image currently being printed is specified. In step S22, the print data after M + 1 is cleared. In step S23, the Mth image that remains in the print buffer without being cleared in step S22 is printed. After that, a cut mark for cutting the sheet is recorded after the Mth image. The recording of this cut mark is the point of this sequence.
In step S24, the drive of the print head is stopped. In step S25, the seat transfer is continued even after the head drive is stopped. In step S26, cutting of the sheet is repeated every time a cut mark is detected. The cut mark recorded after the Mth image at the end is the last cut mark, and this cut is the last. In step S27, the sheet transfer is stopped after the sheet is cut at the final cut mark. In step S28, the continuous sheet cut by the cutter 20 and left on the upstream side is sent back to the sheet supply section 1 (in the case of single-sided printing mode) or the reversing section 9 (in the case of back-side printing in double-sided printing mode) and wound. take. At the same time, the cut sheets cut by the cutter 20 and left on the downstream side have been printed, so they are processed one by one by the information recording unit 7 and the drying unit 8 and discharged to the discharge unit 12. To go.
In this way, when an abnormality in the print head is detected, a cut mark is recorded after the image currently being printed, so that the sheet can be reliably cut at an appropriate position. As for the Mth image, an abnormality occurred during printing, so that the image quality in the latter half of the image may be poor. Therefore, the images up to the M-1st may be output as non-defective products, and the M-th image may be disposed of as a defective product. In this case, in step S22, all the print data including the print data of the Mth image is cleared, and in step S23, the print of the Mth image is not completed and is interrupted in the middle to record only the cut mark. Good. The Mth unfinished image part is cut off by the cutter part 6 and discharged to the trash can 17.
In step S29, a possible cause is displayed on the display of the operation unit 15, and the user is instructed to perform maintenance work to eliminate the abnormality of the print head. In response to this, the user executes maintenance work such as cleaning, spitting complementation processing, or printhead replacement to restore the printhead to a normal state.
In step S30, it is determined whether the maintenance is completed and the printhead is recovered. After recovery, move to step S31. In step S31, the rest of the prints are resumed. In the single-sided print mode, the sheet is sent out again from the sheet supply unit 1 and supplied to the print unit 4, and printing is restarted sequentially from the M + 1th (or Mth) image. In the case of backside printing in the double-sided print mode, the sheet is sent out again from the reversing section 9 and supplied to the printing section 4, and printing is restarted sequentially from the M + 1th (or Mth) image. End the sequence when all prints are complete.
On the other hand, when an abnormality is detected during printing on the first side in the front side printing in the double-sided printing mode, the processing sequence is as follows. In the surface print, the cut mark is not recorded for each margin area. Only inspection patterns are formed in all or part of the margin area. If an abnormality is detected in the print head during surface printing, the print is canceled and a cut mark is recorded for the M + 1st (or Mth) and subsequent images on the first surface. This cut mark is detected by the cut mark sensor 19 and cut by the cutter 20. Then, the continuous sheet printed on the first surface on the downstream side of the cutting position is wound around the reversing section 9, and the continuous sheet on the upstream side of the cutting position is sent back to the sheet supply section 1 and wound up. After this, when the user completes the maintenance, the remaining printing is restarted. The image on the second side corresponding to the image normally printed on the first side and wound up on the inversion portion 9 is specified, and the sequential printing of the second side is restarted from the specified image. End the sequence when all prints are complete.
The cut mark may be detected by using the inspection unit 5 instead of the cut mark sensor 19. Alternatively, the cut mark sensor 19 and the inspection unit 5 may be used in combination to detect the cut mark. In any form, the sensor for detecting the cut mark is provided downstream of the printing position and upstream of the cutting position by the cutter.
When detecting a cut mark, it may become undetectable, and the causes are as follows. (1) When the cut mark is not printed normally: For example, there are cases where the cut mark becomes poorly recorded due to ink shortage of the print head 14 or temporary clogging of the nozzle. In addition, there are cases where the cut mark is poorly recorded due to partial scratches or dirt on the sheet surface. (2) In case of trouble with the sensor itself: In some cases, the sensor receives electrical or optical noise or breaks, resulting in poor detection. In addition, there are cases where detection is poor due to aged deterioration of the light source and the light receiver.
The above (1) and (2) can be distinguished by using the cut mark sensor 19 and the inspection unit 5 together. The cut mark in the margin area is first read and detected by the inspection unit 5, and then the same cut mark is detected by the cut mark sensor 19. If it is detected by both the inspection unit 5 and the cut mark sensor 19, it is in a normal state. On the contrary, if the cut mark cannot be detected in any of the cases, it is determined that the cut mark is not printed normally. If it can be detected by the inspection unit 5 but not by the cut mark sensor 19, it is determined that there is a problem with the cut mark sensor 19. On the contrary, if the inspection unit 5 cannot detect the problem and the cut mark sensor 19 can detect the problem, it is determined that the inspection unit 5 has a problem. In this way, the same cut mark is detected by two sensors in time series, and the cause when the cut mark becomes undetectable is determined based on the detection states of these two sensors.
In the printing apparatus of this embodiment, the inspection unit 5 (first reading unit), the cut mark sensor 19 (second reading unit), and the cutter 20 are arranged in this order downstream of the printing unit 4. The rationality of having such a positional relationship will be described below.
FIG. 10 is an enlarged view of the positional relationship between the inspection unit 5, the cutter unit 6, and the sheet transport path between them. The sheet being conveyed passes through the inspection section 5 and is introduced into the cutter section 6 by changing the traveling direction in the space 30. In the space 30, the seat advances by a path like the state 31 by design. During the period when the cutter 20 of the cutter portion 6 cuts the sheet, all the transport rollers (rollers before and after the cutter 20) of the cutter portion 6 temporarily stop rotating. During that time, the transport roller of the inspection unit 5 continues to rotate, and the sheet continues to be fed from the upstream side. Therefore, in the space 30, the seat has a loop (swelling in the outward direction) as in the state 32. When the cutter 20 finishes cutting, the transport roller of the cutter portion 6 resumes rotation and feeds the sheet downstream at a speed faster than usual. Therefore, the loop of the seat in the space 30 is gradually eliminated. Then, the transfer roller of the cutter portion 6 returns to the normal speed at the timing when the loop is just eliminated. When the next sheet is cut, the sheet stops at the cutter portion 6 again, and the loop becomes large. That is, the size of the loop is constantly changing and not constant. Therefore, the length of the sheet in the transport direction between the inspection unit 5 and the cutter unit 6 is not constant but fluctuates. In this way, a loop is generated in the seat between the inspection unit 5 and the cutter unit 6 downstream of the inspection unit 5 (between the most downstream roller pair 5a of the inspection unit 5 and the most upstream roller pair 6a of the cutter unit 6). Space 30 is provided as a loop forming space that allows this (maximum size of the loop).
Here, the cut mark sensor 19 is provided downstream from the position where the loop is formed (the nip position of the most upstream roller vs. 6a). Therefore, the cut mark recorded on the sheet can be read without being affected by the increase or decrease of the loop. It can be accurately determined that the cutting position of the sheet has come to the cutting position of the cutter 20. Moreover, since the distance between the cut mark sensor 19 and the cutter 20 is very small, more accurate judgment is possible. Since the cut mark sensor can detect the cut mark from a simple change in the amount of light of the optical sensor, it does not take time to detect it, and the small distance between the cut mark sensor 19 and the cutter 20 does not matter.
On the other hand, the inspection process in the inspection unit 5 involves an image process and requires a large amount of calculation, so that a calculation time is required. Therefore, if the distance between the imaging position of the inspection unit 5 and the cutter 20 is small, the calculation may not be in time while the sheet passes. This problem becomes more pronounced as the sheet transport speed increases. Therefore, in the present embodiment, the distance of the transport path between the inspection unit 5 and the cutter 20 is set to an amount sufficient to obtain the time required for the calculation in the inspection unit 5. From the sheet transport speed and distance during this period, the transit time through which the sheet passes is calculated. Make sure that this transit time is not shorter than the calculation time required by the inspection unit 5. From a different point of view, by increasing the distance between the inspection unit 5 and the cutter 20, the sheet transfer speed, that is, the printing speed can be improved. By arranging the loop-forming space 30 and the cut mark sensor 19 in the space between the inspection unit 5 and the cutter 20 created here, the space can be effectively used to reduce the size of the printing device.
For the above rational reasons, the inspection unit 5 (first reading unit), the cut mark sensor 19 (second reading unit), and the cutter 20 are arranged in this order downstream of the print head 14. With this configuration, it is possible to print at high speed and with high quality and cut the sheet one by one with high position accuracy to obtain the final printed matter. In addition, the device can be miniaturized.
In double-sided printing, a loop occurs before the cutting position only when the back side is printed on the second side where the sheet is cut for each unit image. No loops are formed in the surface print on the first side because there is no sheet cutting for each image. Therefore, the rotation speed of the transfer roller of the cutter portion 6 (the transfer roller before and after the cutter 20) does not stop during continuous printing on the first surface and is a constant speed (including a case where the speed is substantially constant). Rotate with. On the other hand, during continuous printing on the second surface, the rotation speed of the transport roller of the cutter portion 6 (the cutter transport mechanism for transporting the sheet near the cutting position by the cutter 20) is set for each unit image. The speed is changed as described above each time the cutting is performed. That is, according to the timing of reading the cut mark by the cut mark sensor 19, the speed of the cutter portion 6 is reduced to zero before cutting to stop, and after cutting, the rotation is restarted to increase the speed more than usual and gradually loop. Eliminate. After that, the speed is returned to the normal speed when the loop is resolved. This is repeated every time the unit image is cut.
That is, the cutter transport mechanism (convey roller of the cutter portion 6) is controlled to transport the sheet at a constant speed without stopping when a plurality of images are sequentially printed on the first surface of the sheet. Subsequently, when a plurality of images are sequentially printed on the second surface of the sheet, the sheet is controlled to be conveyed at a non-constant speed including a stop according to the reading timing of the cut mark by the cut mark sensor 19. In this way, the control method of the cutter transport mechanism can be switched between front side printing and back side printing. In this way, in double-sided printing, high-speed and high-quality printing can be performed, and sheets can be cut one by one with high position accuracy to obtain a final printed matter.
4 Print section 5 Inspection Department 6 Cutter part 9 Inverted part 13 Control unit 14 printhead 19 Cut mark sensor 20 cutter
10 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8 Sheet 9 Sheet 10
Every citation, both ways
| Document | Relation | Office |
|---|---|---|
| JP2004338322A | Cites | Japan |
| JP2002059565A | Cites | Japan |
| JP11249346A | Cites | Japan |
| JP2008162170A | Cites | Japan |
| JP2009132163A | Cites | Japan |
| JP2003231313A | Cites | Japan |
| JP2011143628A | Cites | Japan |
| JP11334187A | Cites | Japan |
4 members in 2 offices
Priority claims2
| Document | Office | Kind | Date |
|---|---|---|---|
| 2010042338 | Japan | A | |
| JP20100042338 | – | – | – |
Members4
| Document | Office | Kind | |
|---|---|---|---|
| US2011211008A1 | United States of America | A1 | |
| JP2011177944A | Japan | A | |
| JP4979784B2This record | Japan | B2 | |
| US8955959B2 | United States of America | B2 |
9 legal events, as the office reported them to INPADOC
Over the term
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| Renewal fee payment (event date is renewal date of database)FPAY | FPAY | |
| Written notification of patent or utility model registrationJAPANESE INTERMEDIATE CODE: R151R151 | R151 | |
| First payment of annual fees (during grant procedure)JAPANESE INTERMEDIATE CODE: A61A61 | A61 | |
| Written decision to grant a patent or to grant a registration (utility model)JAPANESE INTERMEDIATE CODE: A01A01 | A01 | |
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Numbers
- Publication
- 4979784
- Publication, DOCDB
- 4979784
- Publication, EPODOC
- JP4979784B
- Application
- 42338
- Application, DOCDB
- 2010042338
- Application, EPODOC
- JP20100042338
Titles2
- Japanese
- プリント装置
- English
- Printing device
Classification
- CPC, 4
- B41J3/60
- B41J11/663
- B41J13/0045
- B41J29/393
- IPC, 6
- B41J29 38
- B41J11 42
- B41J11 70
- B41J29 40
- B41J29 46
- B65H35 04
