JP2008022160A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that avoids edge detection operations at a fully closed white original document retainer to wasteful determination of an original size, in the case of reading the document so as to reduce a time until an image output. <P>SOLUTION: A user selects whether the edge detection is to be performed when the original document retainer is fully closed for the determination of the original size in the image forming apparatus. When reading of a white original document is known in advance, the edge detection at the fully closed retainer is not performed, and only the original document size determination is made by the edge detection at a half-closed retainer, so that the reading of the original document is more quickly started. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus having execution control of a document edge detection method performed when determining a document size.

  Conventionally, as a method of determining the paper size of a document in an image forming apparatus, the document table is scanned with an optical reading device while the document presser (platen cover) is closed (first scanning). ) After the document presser is fully closed, the document table is scanned again by the optical reading device (second scanning) to read the edge of the document (see Patent Documents 1 and 2).

  In this method, since the document presser is not closed in the first scanning, light is not reflected from a portion where the document is not present (background) and the image is black, so that contrast with the background can be obtained in the case of a white document. In the second scanning, the document holder is closed, and the background portion appears white due to the reflection of light from the white plate portion in contact with the document table of the document holder. In the case of a manuscript, contrast with the background can be obtained and edges can be detected.

  However, in this method, the second scanning for detecting the edge of the colored document is performed before the image reading of the image forming apparatus, and there is a problem that it takes time to start the image reading.

  Since most of the originals scanned in the image forming apparatus are white originals, in most cases, the time until the image reading start of the image forming apparatus is delayed by performing the second scan unnecessarily. It was.

JP-A-8-204912 Japanese Patent Laid-Open No. 11-122582

  The problem to be solved is that in the image forming apparatus, even when reading a white document, edge detection is performed when the document presser is fully closed, and unnecessary operations and time are consumed before the image forming apparatus reads the image. It is.

  An image forming apparatus according to the present invention includes a document table on which a document for reading a document is set, a document press attached to the document table so as to be openable and closable, an open / close detection unit for detecting an open / closed state of the document press, and the document An image information reading unit that scans a document set on a table and reads image information of the document; and an edge detection unit that detects an edge of the document set on the document table. In the image forming apparatus in which the edge detection unit detects the edge of the document when the half-closed time is detected and when the open / close detection unit detects the fully closed time of the document presser, the document presser is fully closed. The main feature is that a selection input unit is provided for the user to select and input whether or not to perform edge detection at the time.

  The image forming apparatus according to the present invention includes a document table on which a document for reading a document is set, a document press attached to the document table so as to be openable and closable, an open / close detection means for detecting an open / closed state of the document press, and the document An image information reading unit that scans a document set on a table and reads image information of the document; and an edge detection unit that detects an edge of the document set on the document table. In the image forming apparatus in which the edge detection unit detects the edge of the document when the half-closed time is detected and when the open / close detection unit detects the fully closed time of the document presser, the document presser is fully closed. The most important feature is that the user has a selection input unit for selecting and inputting whether or not edge detection is to be performed. No longer perform the document holder is fully closed edge detection operation for unnecessary document size determination in, it becomes possible to shorten the time until the image output of the image forming apparatus.

  In the image forming apparatus, when the white document is read, in order to prevent the edge detection operation when the document presser is fully closed for determining an unnecessary document size, the edge detection operation when the user fully closes is performed in advance. It was realized by selecting and inputting whether or not to perform.

  An image forming apparatus as one embodiment of the present invention will be described below.

[Function configuration]
FIG. 1 is a functional block diagram of the image forming apparatus 1 according to the first embodiment.

  The image forming apparatus 1 includes an image information reading optical unit 101 (image information reading unit), an operation panel unit 103 (selection input unit), a document pressing open / close detection unit 105 (open / close detection unit), a printing unit 107, a control unit 109, a FAX. It consists of a transmission / reception unit 111.

  The image information reading optical unit 101 includes an optical sensor and an optical system. The image information reading optical unit 101 reads image information on the document on the document table (image information reading unit) and also detects an edge of the document (edge detection unit).

  The operation panel unit 103 includes an input interface such as an output panel and a touch panel, and prompts the user for an operation or receives an input from the user.

  Also, it functions as a selection input unit for inputting selection as to whether or not to perform edge detection when fully closed.

  The document press opening / closing detection unit 105 includes a half-closed detection sensor and a full-closed detection sensor attached to the document press on the document table, and detects the open / closed state of the document press (open / close detection means).

  The printing unit 107 prints image data read by the image detection optical unit.

  The control unit 109 controls the entire image forming apparatus, and based on input signals from the image information reading optical unit 101, the operation panel unit 103, and the document pressing open / close detection unit 105, the image information reading optical unit 101. On the other hand, it controls whether or not to perform edge detection.

  The FAX transmission / reception unit 109 performs FAX transmission / reception.

[Constitution]
FIG. 2 shows a side view of the image forming apparatus 1.

  The image forming apparatus 1 includes a document table 5 for reading a document on the upper part of the device and a document holder 3 that covers the document table and serves to suppress the document on the document table.

  A half-closed detection sensor 11 and a full-closed detection sensor 13 for detecting the open / closed state of the document presser are attached to the base of the open / close portion of the document presser 3.

  The control unit 109 reads the signals of these sensors 11 and 13 and determines the open / close state of the document presser.

  FIG. 3 is a sectional view of the inside of the image forming apparatus, and the optical system will be described.

  The image forming apparatus 1 includes a CCD sensor 21, a condensing lens 23, an optical system mirror 25, and a document reading light source 27, and constitutes an image information reading optical unit 101. The document 7 placed on the document table 5 is illuminated by the document reading light source 27, reflected from the plurality of optical system mirrors 25, passes through the condenser lens 23, and forms an image on the CCD sensor 21.

  In this embodiment, when the optical system functions as an edge detection unit, the edge of the document 7 is detected by the CCD sensor 21, and when the optical system functions as an image information reading unit, the document reading light source 27 matches the reading accuracy. A low speed scan is performed to read the image.

[Flow of operation]
An operation flow of the image forming apparatus 1 according to the present embodiment will be described with reference to a flowchart of FIG.

  When the image forming apparatus 1 starts its operation, it is selected in step S201 whether or not to perform the edge detection operation at the fully closed time for determining the document size, based on an input from the operation panel unit 103.

  When the operation of closing the document presser is performed, the operation is detected by the half-closed detection sensor 11, and the operation shifts to the step of S203, and the edge detection when the document presser is half-closed by the optical system of the image information reading optical unit 101 is performed. I do.

  In step S205, the process branches according to the item selected in step S201.

  If it is selected in S201 that the edge detection operation when fully closed is not performed, the operation proceeds to S207, and the document size is determined by analyzing the image data obtained by the edge detection when half closed in S203.

  Next, according to the document size determined in the previous step S207, printing by the printing unit 107 or FAX transmission by the FAX transmitting / receiving unit 111 is performed (S213), and the operation is terminated.

  If it is selected in S201 that the edge detection operation when fully closed is performed, the operation panel unit 103 sends a signal for performing edge detection when fully closed to the control unit 109, and the operation shifts from S205 to S209. When the fully closed detection sensor 13 detects that the document presser is fully closed, a fully closed edge detection operation is performed.

  In step S211, the document size is determined based on the half-closed edge detection data measured in step S203 and the full-closed edge detection data measured in step S209. If the edge detection data in the half-closed state differs from the edge detection data in the fully-closed state at this time, the larger document size is adopted.

  For example, as shown in FIG. 5A, in the case of a document having a high density on the lower side of the B5 size in the scanning direction (vertical direction in the figure) of the A4 size document placed on the document table, FIG. As shown in the figure, the document size is detected as B5 in the half-closed document size detection operation, and is recognized as A4 size when fully closed. In that case, the document size is correctly determined by determining the larger A4 size.

  For example, as shown in FIG. 6A, in the case of a document having a higher density on the upper side than the A5 size in the scanning direction (vertical direction in the figure) of the A4 size document placed on the document table, FIG. ), It is recognized as A4 size in the document size detection operation when half-closed, and is recognized as A5 size when fully closed. In that case, the document size is correctly determined by determining the larger A4 size.

  Returning to the flowchart, next, image output is performed in the same manner as described above in S213 based on the document size determined in S211.

  The series of operations is thus completed.

[Effect of Example]
In the image forming apparatus according to the present embodiment, it is possible to specify whether or not to perform the full-closed edge detection operation based on an input from the user, so that the document size is accurately determined in advance by half-closed edge detection like a white document. When it is known that the edge detection operation is not performed when fully closed, it is possible to output an image earlier without performing the edge detection operation when fully closed.

  Also, in the case of a document with a colored edge such as a photo document, the edge size can be determined by detecting the fully closed edge.

  In this embodiment, since the CCD sensor used for the edge detection means and the CCD sensor used for the image information reading means are shared by the same one, the cost can be reduced.

[Others]
In this flowchart, only the flow of automatic document size determination of the image forming apparatus 1 has been described. However, the image forming apparatus 1 determines the document size in advance by the user determining the document size in advance by input from the operation panel unit 103. A method that does not perform the detection operation may be provided.

  In this embodiment, the optical sensor used for the edge detection means and the optical sensor used for the image information reading means are shared by the same one, but a dedicated sensor may be provided for each.

1 is a functional block diagram of an image forming apparatus (first embodiment). 1 is a schematic diagram of an image forming apparatus (Example 1). FIG. 1 is an optical system diagram of an image forming apparatus (Example 1). 1 is a flowchart of an image forming apparatus (first embodiment). Example in which the detection size when fully closed is larger than the detection size when half closed (Example 1). An example in which the detection size when half-closed is larger than the detection size when fully closed (Example 1)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 3 Original pressing 5 Original stand 7 Original 11 Half-closed detection sensor (open / close detection means)
13 Fully closed detection sensor (open / close detection means)
21 CCD sensor (image information reading means, edge detection means)
23 Condensing lens (image information reading means, edge detection means)
25 Optical mirror (image information reading means, edge detection means)
27 Document table reading light source (image information reading means, edge detection means)
101 Image information reading optical unit (image information reading means, edge detection means)
103 Operation panel section (selection input section)
105 Document holding open / close detection unit (open / close detection means)
109 Control unit

Claims (3)

A document table on which a document for reading a document is set, a document press attached to the document table so as to be openable and closable, an open / close detection means for detecting an open / closed state of the document press, and a document set on the document table are scanned. Image information reading means for reading the image information of the document and edge detection means for detecting the edge of the document set on the document table,
An image forming apparatus that detects an edge of a document by the edge detection unit when the open / close detection unit detects a half-closed time of the document presser and when the open / close detection unit detects a fully closed time of the document presser. In
An image forming apparatus, comprising: a selection input unit through which a user selects and inputs whether or not to perform edge detection when the document presser is fully closed. The image forming apparatus according to claim 1,
If each document size determined by the edge detection when the open / close detection means detects the half-closed state and the fully-closed state of the document presser is different, the larger one of the document sizes An image forming apparatus, wherein the size is selected as a detected document size. The image forming apparatus according to claim 1,
An image forming apparatus characterized in that the edge detection unit and the image information reading unit share an optical sensor.

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