JP2005159802A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus for carrying out collation that sets and selects a collation range so as to be able to select a collation time thereby attaining free setting of reliability and productivity resulting in reducing the cost. <P>SOLUTION: The image forming apparatus has two collation methods or more and includes: a means for setting and selecting the collation method; and a means for predicting and displaying a collation time depending on the setting and the selection. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus such as a printer, a copying machine, a facsimile machine, and a multifunction machine. In particular, the present invention relates to an image forming apparatus that performs collation.

In an image forming apparatus, the possibility that an abnormality will occur in an image-formed sheet is not zero. For example, there are image abnormalities such as image smudges and image omissions, and sheet abnormalities such as sheet skew, folding and scratches. Conventionally, in order to guarantee this, a sheet on which an image has been formed is read and checked for any abnormality. In the case of collation, a collation time such as a reading time and a collation processing time is required, and as a result, productivity may be reduced. The reading unit scans the sheet at a constant cycle, and reads the image on the sheet and the shape / posture of the sheet such as skew, folds, and scratches of the sheet. The resolution to be read is determined by the sheet conveyance speed and the scanning period of the reading unit. If the transport speed Vps (m / s) and the scanning period Tr (s) of the reading means are used, the resolution is Vps / Tr. To scan at a higher resolution than that, it is necessary to reduce the sheet conveyance speed. As a result, the number of output sheets per unit time, that is, productivity is lowered. In addition, the data read by the reading unit is collated with the image data of the collation source for any abnormality. The more time required for verification, the more time is required. In order to keep up with the processing of the next sheet, it is necessary to make the time between sheets longer than the processing time. As a result, productivity decreases. Therefore, in order to shorten the collation time and avoid a decrease in productivity, a high-performance reading means with a short reading time and a high-performance collating means with a short collation processing time were used. there were. In order to reduce the data by using a normal reading means and collating means at low cost and shortening the collating time, it is possible to partially collate or patternize and collate to reduce data. A collation method is used. Conventionally, collation for guaranteeing an image-formed sheet is mainly collation when printing a large amount of banknotes or specific images, and the collation method is one method. Or, even if there are a plurality of methods, the setting and selection of the collation method are fixed. Alternatively, only image abnormalities are collated. (For example, refer to Patent Document 1.)
Japanese Patent Publication No. 04-020231

  However, in recent years, it has been considered to collate in order to guarantee a sheet on which an image is formed even when printing a small lot. As a result, various requests are generated and it is impossible to respond to this. For example, it is sufficient to collate only a part of image abnormalities and to output an image in a short time. Alternatively, there may be a case where, for a skewed sheet, a folded sheet, a scratch, and the like, only an abnormality that causes a conveyance failure is detected, and an image abnormality is not desired to be detected. In these cases, it is necessary to change the setting of the collation method and to select which method to use. In other words, it is necessary not to match all the abnormalities and satisfy all the guarantees of the sheet on which the image is formed, but to set and select the checking range as desired and select the checking time. It is also necessary to prioritize which abnormality is to be checked. Alternatively, in order to collate only the sheet abnormality, it is necessary to collate only the end portion of the sheet and shorten the collation time.

  (1) In an image forming apparatus that forms an image of image data on a sheet, a reading unit that reads an image or a shape / posture of an image-formed sheet, and a checking unit that checks the image data and read data read by the reading unit It has two or more collation methods of collation means, and has setting / selection means for setting and selecting collation methods.

  (2) As a collation method in (1), partial collation for collating part of image data and read data, pattern collation for pattern matching of image data and read data, and full collation for collating all of image data and read data And

  (3) In (1) to (2), the priority of the collation method is set.

  (4) The data part to be collated in (1) is set in advance as the sheet edge, and only that part is collated.

  (5) In (1), the prediction calculation means for calculating other values based on the prediction time and the predicted time, and the predicted time and the calculation result are displayed by setting and selecting the verification method. Has display means.

  (6) In (5), the number of output sheets per minute is calculated and displayed.

  (7) In (5), the number of output sheets per minute is changed according to the calculation result.

  According to the present invention, it is possible to select a collation time by setting / selecting a collation range as desired, thereby improving operability. As a result, it is possible to freely select productivity reduction and collation guarantee by collation, and it is possible to realize an image forming apparatus that is easy to use and can handle image guarantee. In addition, it is possible to perform collation of sheet abnormalities that cause sheet conveyance abnormalities such as skewing and folding that lead to reduced productivity, reducing the verification time, and reliability that minimizes productivity degradation. Can be provided at low cost.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a digital composite copying machine as an example of an image forming apparatus according to an embodiment of the present invention. FIG. 2 shows an external view. 2001 is an operation unit to be input when setting / selecting. 2002 is a display unit for displaying the contents. Reference numeral 1 denotes a digital composite copying machine main body, and an original platen 2 made of a transparent glass plate fixedly provided is provided on the upper part of the main body 1. Reference numeral 3 denotes a document feeding device that conveys a sheet-like document to a predetermined position on the document table 2. The document conveyed to the document table 2 by the document feeding device 3 is read by the reading unit 4 and read. The data is processed by the image processing unit, converted into an electrical signal, and transmitted to the writing laser unit 5.

  Here, the digital composite copying machine body 1 functions as a copying machine when data from the reading unit 4 is input to the writing laser unit 5, and functions as a printer when an output signal of a personal computer is input. Further, if a transmission signal from the facsimile machine of another machine is input and a signal from the reading unit 4 is transmitted to the facsimile machine of the other machine, it functions as a facsimile machine. Based on these input data, the writing laser unit 5 emits laser light and scans the photosensitive drum 12.

  1A is a sheet feeding unit. This sheet feeding unit 1A is an image forming unit configured to store sheets S stored in decks 30 and 31 and sheet cassettes 32 and 33, which are sheet storage units built in the digital multifunction copying machine body 1. Multi-feed unit 210, which is a manual feed device with deck feed units 34 and 35 and cassette feed unit 36.37 for feeding 1B, and a sheet feed tray 74 and sheet feed unit 210A, which are sheet stacking units, is provided. It has been.

  The image forming unit 1B includes an electrophotographic photosensitive drum 12, a charger 13, a developing device 14, a transfer charger 19 and the like. Then, a laser beam corresponding to the image information emitted from the writing laser unit 5 is scanned on the surface of the photosensitive drum 12 uniformly charged by the charger 13 to form a latent image. A toner image is formed by the toner image 14, and the toner image is transferred onto the upper surface of the sheet S by the transfer charger 19 on the sheet S conveyed in synchronization with the rotation of the photosensitive drum 12. Further, a separation charger 20 for separating the transferred sheet and a cleaner 26 for removing the toner remaining on the drum 12 are also provided.

  Further, downstream of the image forming unit 1B, a conveyance unit 21 that conveys the sheet S on which the toner image is transferred, and a fixing device 22 that fixes the image on the sheet S conveyed by the conveyance unit 21 are provided. ing. Further, a discharge roller 24 that discharges the sheet from the main body 1 is provided on the downstream side of the fixing device 22. The sheet S on which the toner image is formed is conveyed to the fixing device 22 and heated and pressed to fix the toner image on the surface of the sheet S. After the fixing, the sheet S is discharged by a discharge roller 24 to a discharge tray 25 or a post-processing device 26 (not shown). On the downstream side of the discharge roller 24, reading means 1001 and 1002 are provided for reading the image of the image-formed sheet or the shape / posture. The reading means 1001 and 1002 are contact image sensors (CIS) incorporating an image sensor and a light source for illumination. The sheet is discharged by the discharge roller 24 in the following three patterns. (1) The image surface is discharged at the top. (2) The image surface is discharged below. (3) The image surface is discharged on both upper and lower sides. In the case of (2), the sheet is reversed and discharged by the double-sided reversing / double-sided conveyance path 121, the reverse large roller 115, and the like. In the case of (3), the sheet is reversed by the double-sided reversing / double-sided conveying path 121, the reverse large roller 115, the conveying rollers 112 to 114, and re-conveyed to the image forming unit 1B, and the second surface is recorded. , Fixed and discharged. By providing the reading means 1001 and 1002 on the upper and lower sides, it is possible to read the image or the shape / posture of the sheet discharged in these three patterns.

  The reading units 1001 and 1002 scan the sheet discharged by the discharge roller 24 at a constant cycle, and read the image on the sheet and the shape / posture of the sheet such as skew, bending, and scratches. Further, the data read by the reading means 1001 and 1002 is collated with the image data of the collation source for any abnormality.

  FIG. 3 shows a flowchart for setting / selecting the collation between the data read by the reading means 1001 and 1002 and the image data of the collation source. S1 is a step of setting / selecting a range of read data. In S1, when data on the entire surface of the sheet is read, a part of data is read, or a part of the data is read, it is set / selected whether data is thinned out or only an area on the sheet is read. All abnormalities can be detected by reading the entire data. When reading with thinning out, the resolution decreases, so the abnormality detection level decreases. When only a certain area is read, only some abnormalities are detected. For example, when detecting an image abnormality (scattering, unevenness, missing image, dirt, etc.) at the tip, only the tip is read. When detecting paper breaks, read the four corners of the paper. When detecting skew, the leading end position of the paper and the leading end position of the image are read. If the amount of data is small, the verification time is shortened.

  S2 is a step of setting / selecting a data processing method. In S2, set / select whether to pattern. The collation accuracy and the collation time change between the case of processing as it is and the case of collation by pattern. Numerous methods have been proposed for this method, and the present invention is not limited. Setting and selecting a method having a different collation time is the main point of the present invention.

  S3 is a step for setting / selecting collation contents. In S3, it is a step of collating image abnormality, collating sheet abnormality, or setting / selecting the content. An image abnormality is that the image is different from the original data. For example, the toner scatters and the image becomes thick or crushed, the toner is not transferred, a part of the image is lost, or the position of the image is shifted. A sheet abnormality is a skew, fold, or scratch of the sheet.

  S4 is a step of performing a prediction calculation. In S4, the collation time is calculated from the data amount and the collation contents when set and selected in S1 to S3. The more time required for verification, the more time is required. If the processing does not end in the normal sheet-to-sheet time due to the processing time (the collation time is greater than a certain value), the sheet-to-sheet time is changed. In this case, the number of output sheets per minute is calculated based on the time between sheets. Further, in order to easily understand how much the productivity decreases, the ratio between the maximum number of sheets and the number of output sheets per minute when set and selected in S1 to S3 is calculated. For example, when the maximum number of sheets is 105 / min and the number of output sheets set and selected in S1 to S3 is 98 / min, the ratio is 98/105 = 0.933 ... = 93.3 ...% It becomes.

  S5 is a step of displaying. In S5, the ratio between the setting / selection contents in S1 to S3 and the number of output sheets per minute and the maximum number calculated in S4 is displayed. For example, “Verification: Part, pattern A, fold and tip blur, number of output sheets = 98 sheets / min, ratio of 93.3% to the maximum” (FIG. 4). The display contents / method in this case is not particularly limited, and any setting / selection contents and productivity (collation time) resulting therefrom can be used.

  S6 is a step of confirming the setting / selection. Check if the displayed contents in S5 are acceptable. If OK, go to S7. If NG, return to S1 and select the setting again. S7 is a step of setting a paper interval time. The paper interval time in the previous setting / selection is set and the operation proceeds to the next operation.

  In FIG. 3, the order is S1 to S3, but the setting / selection order of each item is not limited.

  Further, the following three types of image data can be considered as the collation source image data.

  (1) When the original is a collation source: data from the reading unit 4, (2) When the electronic data is a collation source: data such as an output signal of a personal computer, a transmission signal from a facsimile machine of another machine, ( 3) When a part of the output paper is used as an inquiry source: Data obtained by reading the part of the output sheet by the reading means 1001 and 1002. When the sheet is pre-printed paper or tab paper, the image (1) or (2) verification always results in an image abnormality or sheet abnormality. This is to prevent this. Further, the image data collation source and the abnormality detection level can be set and selected according to the mode and conditions. Thereby, false detection can be prevented and reliability can be improved.

  Further, upstream of the reading means 1001 and 1002, means 105, 106, 116, 117, 118, 119, 120 and the like for detecting sheets are provided in each part. When these sensors detect unusual events or perform different actions (long paper interval, short, paper re-feed operation with paper feed, paper feed stage switched) Change the verification method. When the situation changes, it is considered that an abnormality is likely to occur, and in that case, the range of collation is changed to improve the abnormality detection accuracy. Thereby, the reliability is improved.

  In the embodiment of the present invention, it is not necessary that the operation unit 2001 for inputting when setting / selecting and the display unit 2002 for displaying contents are integrated with the main body 1. For example, it may be displayed on a computer connected via a network. Also, setting / selection items are not particularly limited. Further, two reading units 1001 and 1002 are arranged, but they may be arranged on the downstream side of the fixing device 22 and upstream of the double-sided reversing / double-sided conveyance path 121 to be one. Further, although the electrophotographic image forming apparatus is used, it is not particularly limited, and it is needless to say that an ink jet system, a thermal transfer system, or the like may be used.

1 is a schematic configuration diagram of a digital composite copying machine (image forming apparatus) according to an embodiment of the present invention. External view. The flowchart of 1st Embodiment. Display screen when setting / selecting.

Claims (7)

In an image forming apparatus that forms image data on a sheet,
Reading means for reading the image or shape / posture of the image-formed sheet;
A collation unit for collating the image data and the read data read by the reading unit;
Have two or more collation methods,
An image forming apparatus having setting / selection means for setting and selecting a collation method. In claim 1,
As a verification method,
Partial verification to verify part of image data and scanned data,
Pattern matching for patterning image data and scanned data
All verifications that verify all image data and scanned data,
Collation without collation that does not collate image data with scanned data,
An image forming apparatus. In claim 1,
An image forming apparatus, wherein a priority of collation methods is set. In claim 1,
Set the data part to be collated in advance as the sheet edge,
An image forming apparatus characterized by collating only that portion. In claim 1,
It is characterized by having prediction calculation means for calculating other values based on prediction time and predicted time by setting and selecting the verification method, and display means for displaying the predicted time and calculation result. Image forming apparatus.   6. The image forming apparatus according to claim 5, wherein the number of output sheets per minute is calculated and displayed. 6. The image forming apparatus according to claim 5, wherein the number of output sheets per minute is changed according to a calculation result.

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