JP2005304064A - Original reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an original reader wherein damage and breakdown to an original are prevented while making the throughput of a reading operation of the original quick, and the miniaturization of a device size is enabled. <P>SOLUTION: One side of the original is read by a first side reading means while the original is conveyed by an original conveyance means so that a curve showing a conveyance path of the original becomes a curve of an almost reverse U shape. The other side surface of the original is read by a second side reading means which is arranged so as to face the first side reading means interposing the curve. As a result, both surfaces of the original are read. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a document reading apparatus that reads both sides of a document and is applied to a scanner, a facsimile machine, a copying machine, and the like.

Conventionally, in order to read both sides of a document, a large number of documents placed on a document placing table are separated and conveyed one by one, and the image surface of the document is read by a reading unit that reads the image surface of the document. There is known a document feeding device (hereinafter referred to as ARDF) with an automatic reversing function for reversing the top and bottom surfaces of the document as a document reversing means for reversing the top and bottom surfaces with respect to the document transport direction. Also known is one that has two optical systems and simultaneously reads both sides of a document that is in close contact with a transparent member (see, for example, Patent Document 1).
JP-A-4-234258

  In the ARDF described above, a large number of documents stacked on the document placement table are separated one by one and conveyed to a predetermined reading position where the image surface is read. Inverted, transported to the reading position again, and after the back side of the image surface is read, the image is discharged onto a discharge document table. For this reason, there has been a problem that the throughput of the document reading operation cannot be increased. Furthermore, since the document transport path is complicated, there is a high possibility that the document is likely to be damaged or broken. Further, in the above-described Japanese Patent Application Laid-Open No. 4-234258, when a document placed with the image surface facing vertically upward is conveyed and both sides of the document are read simultaneously, the back side of the image surface is read. There is a problem in that it is difficult to reduce the size of the apparatus because it is necessary to install the image reading means inside the portion where the document is fed.

  SUMMARY OF THE INVENTION An object of the present invention is to increase the throughput of a document reading operation and to prevent the document from being damaged or broken, thereby reducing the size of the apparatus.

  In order to achieve the above object, the invention described in claim 1 is characterized in that an original conveying means for conveying the original so that the curve indicating the original conveying path becomes a substantially inverted U-shaped curve, and one of the originals A first one-side reading unit that reads a surface; and a second one-side reading unit that is provided so as to face the first one-side reading unit across the curve and reads the other surface of the document; The first single-side reading means reads one side of the original while the original is conveyed so that the curve becomes a substantially inverted U-shaped curve, and the second single-side reading means causes the second single-side reading means to read the original. By reading the other side, both sides of the original are read.

  According to a second aspect of the present invention, in order to achieve the above object, in the first aspect of the present invention, the document conveying means increases the document conveying speed as the document advances along the conveying path. It is characterized by comprising a conveyance speed tilting means for conveying the document.

  In order to achieve the above object, the invention according to claim 3 is characterized in that, in the invention according to claim 1 or 2, the first single-sided reading means is detachably provided to the apparatus main body. To do.

  According to the present invention, the first single-side reading unit reads one side of the original, and the first single-side reading unit is provided so as to face the first side of the original with a curve indicating a conveyance path of the original. By causing the two-sided reading means to read the other side of the document, both sides of the document are read, so that it is not necessary to transport the document twice to a predetermined reading position in order to read both sides of the document. The throughput of the original reading operation can be increased, and the original conveyance path can be prevented from becoming complicated. For this reason, it is possible to prevent the original from being damaged or broken. Further, since the document is conveyed such that the curve indicating the document conveyance path is a substantially inverted U-shaped curve, the length of the document reading device in the document conveyance direction is set to the length of the actual document conveyance path. The size of the original reading apparatus can be reduced.

  In addition, since the document conveying means includes the conveyance speed tilting means for conveying the document so that the document conveyance speed increases as the document travels along the conveyance path, The original is conveyed with the leading edge of the original being pulled with respect to the end, and the original can be conveyed without causing local elongation, and a good image without shrinkage can be obtained.

  In addition, since the first single-sided reading unit is detachably provided to the apparatus main body, maintenance and jam processing of the apparatus main body can be easily performed.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of a document reading apparatus according to the present invention. 2 and 3 are views showing a part of the document reading apparatus according to the embodiment.

  First, the configuration will be described.

  FIG. 1 is a schematic overall configuration diagram of an embodiment of a document reading apparatus according to the present invention. In the document reading apparatus shown in FIG. 1, reference numeral 1 denotes a document reading apparatus. The document reading apparatus 1 includes a sheet document automatic feeding unit 2 and a main body scanner unit 3.

  The sheet document automatic feeding unit 2 includes a sheet feeding unit 4, a document conveying unit 5 that conveys the document so that a curve indicating a document conveyance path is a substantially inverted U-shaped curve, and one of the documents. A first single-sided reading unit 6 for reading a surface, a paper discharge tray 7 for stacking originals conveyed by the original conveying unit 5 and read on both sides by the first single-sided reading unit 6 and the main body scanner unit 3, A document sensor 9 that detects the presence or absence of a document in the document tray 8 that is a component, a feed roller 10 that is a component of the sheet feeding unit 4 and the document conveying means 5 when the document is fed and separated. A paper feed sensor 12 that turns off the driving of the rollers 11, a reading sensor 13 that detects the reading timing of the conveyed document, a paper discharge sensor 14 that detects discharge of the conveyed document to the paper discharge tray 7, It has.

  The paper feed unit 4 includes a document tray 8 and a bottom plate 15 having a top surface on which a sheet-like document is placed, a paper feed spring 16 that pushes up the bottom plate 15 to apply a paper feed pressure to the document, and a top surface of the bottom plate 15. The pickup roller 17 is configured to convey a large number of placed originals in order from the uppermost original.

  The document conveying means 5 includes a feed roller 10, a separation roller 11, and conveyance rollers 18 to 27. The first single-sided reading means 6 is composed of an equal magnification sensor, and is provided in a conveyance reversing unit 30 composed of guide plates 28 and 29. As shown in FIG. 1, a reading back plate 31 is provided via a spring 32 at a position symmetrical to the first single-sided reading means 6 with respect to the curve indicating the document conveyance path. The spring 32 elastically presses the reading back plate 31 toward the first single side reading means 6 so that a predetermined gap is secured between the reading back plate 31 and the first single side reading means 6.

  The main body scanner unit 3 includes a second single-sided reading unit 33 that is provided so as to face the first single-sided reading unit 6 across the curve indicating the document conveyance path and reads the other side of the document. The reading means 33 includes a first traveling body 36 composed of an illumination 34 and a first mirror 35, a second traveling body 39 composed of a second mirror 37 and a third mirror 38, a lens 40, and a photoelectric sensor. Conversion means 41 and contact glass 42 having an upper surface on which the conveyed document is placed are provided. The photoelectric conversion means 41 is composed of a CCD (Charge Coupled Device). The first traveling body 36 and the second traveling body 39 are moved at a speed of 2: 1 by a motor (not shown) via a wire or a timing belt (not shown), respectively, and a document placed on the upper surface of the contact glass 42 is moved. Scan. The image of the original is formed on the photoelectric conversion means 41, converted into an electric signal, and subjected to image processing on the control board 43.

  As shown in FIG. 1, a reading back plate 44 is provided via a spring 45 at a position symmetrical to the second single-sided reading means 33 with respect to a curve indicating the document conveyance path. The spring 45 elastically presses the reading back plate 44 toward the second single side reading means 33 so that a predetermined gap is secured between the reading back plate 44 and the second single side reading means 33.

  FIG. 2 is a partial schematic configuration diagram of a document reading apparatus according to an embodiment. In the document reading apparatus shown in FIG. 2, reference numeral 51 denotes a document reading apparatus, and the document reading apparatus 51 includes a sheet document automatic feeding unit 52 and a main body scanner unit (not shown). The sheet document automatic feeding unit 52 is configured in the same manner as that shown in FIG. The document conveying means is composed of a conveying speed tilting means 55 for conveying the document so that the document conveying speed increases as the document advances along the conveying path.

  In the document reading apparatus 51 shown in FIG. 2, the conveyance rollers 68 to 77 constituting the conveyance speed tilting unit 55 are those 68 to 71 on the upstream side of the document conveyance path of the first single-sided reading unit 56, and the first single-sided reading. The ones on the downstream side of the document transport path are the ones 72 and 73 provided between the means 56 and the second single-sided reading means (not shown) and the ones 74 to 77 on the downstream side of the document transport path of the second single-sided reading means. It is provided so that the outer diameter gradually increases.

  FIG. 3 is a partial schematic configuration diagram of a document reading apparatus according to an embodiment. In the document reading apparatus shown in FIG. 3, reference numeral 101 denotes a document reading apparatus. The document reading apparatus 101 includes a sheet document automatic feeding unit 102 and a main body scanner unit (not shown). The sheet document automatic feeding unit 102 is configured in the same manner as that shown in FIG. A first single-sided reading means 106 is detachably provided on the document reading apparatus 101 main body.

  Next, the operation will be described.

  In the document reading apparatus 1 shown in FIG. 1, the documents fed by the sheet feeding unit 4 are separated one by one by the feed roller 10 and the separation roller 11, and the document reversing unit 30 is illustrated by the document conveying unit 5. 1 is conveyed while drawing a substantially U-shaped conveyance path as shown in FIG. 1, one surface being conveyed is read by the first single-sided reading means 6, and the original conveying means toward the main body scanner unit 3. 5, the other surface is read by the second single-side reading means 33, and then discharged to the paper discharge tray 7.

  In the document reading apparatus 1, since the first single-sided reading means 6 is provided in the conveyance reversing unit 30, the main body of the document reading apparatus 1 can be miniaturized. In particular, the conventional scanner for single-sided documents in the longitudinal direction. Can be equivalent.

  In the case shown in FIG. 1, the original is conveyed to the first single-sided reading means 6 while the original is conveyed so that the original conveying means 5 has a substantially inverted U-shaped curve. The document being transported is read by the second single-sided reading means 33 provided to read one side of the document inside and to face the first single-sided reading means 6 across a curve indicating the document transport path. By reading the other side of the document, both sides of the document are read, so that it is not necessary to transport the document twice to a predetermined reading position in order to read both sides of the document, thereby reducing the throughput of the document reading operation. It is possible to increase the speed and to prevent the original transport path from becoming complicated. For this reason, it is possible to prevent the original from being damaged or broken. Further, since the document is conveyed so that the curve indicating the document conveyance path is a substantially inverted U-shaped curve, the length of the document reading apparatus 1 in the document conveyance direction is set to the length of the actual document conveyance path. Therefore, the size of the document reading apparatus 1 can be reduced.

  In the document reading device 51 shown in FIG. 2, the conveyance rollers 68 to 77 are provided such that the outer diameter is gradually increased toward the downstream side of the document conveyance path, and each conveyance roller has a predetermined same rotational speed. Since it is rotated, the reading line speed of the second single-sided reading means (not shown) is slightly higher than the reading line speed of the first single-sided reading means 56. For this reason, the original, which is paper, is always pulled toward the downstream side in the original conveyance direction, and the original can be read with the paper tightly stretched, and local elongation occurs in the original. Therefore, a good image without shrinkage can be obtained, and a good original can be read.

  In the document reading apparatus 101 shown in FIG. 3, the guide plate 128 is provided so as to be rotatable about a fulcrum C. Since the first single-sided reading means 106 can be exposed in the rotated state as shown in FIG. 3, the first single-sided reading means 106 can be easily detached from the main body of the original reading apparatus 101 by loosening a fixing screw or the like. be able to. Therefore, maintenance and jam processing of the document reading apparatus 101 main body can be easily performed.

  In addition, in one embodiment of the document reading apparatus according to the present invention, the second single-side reading means is configured to be detachable from the apparatus main body in the same configuration as that shown in FIG. 1 having the same configuration as that shown in FIG. 1, in which the first single-sided reading means and the second single-sided reading means are provided detachably with respect to the apparatus main body, the same as that shown in FIG. 2 in which the outer diameter of the conveying roller constituting the original conveying means is made constant and the conveying roller on the downstream side in the original conveying direction is rotated at a larger rotational speed, the same configuration as that shown in FIG. In this case, the outer diameter of the conveying roller constituting the document conveying unit and the rotation speed applied to the conveying roller are appropriately controlled so that the reading linear velocity of the second single-sided reading unit becomes the reading linear velocity of the first single-sided reading unit. Something that makes it faster, 2, the outer diameter of the conveying roller constituting the document conveying means and the number of rotations applied to the conveying roller are appropriately controlled, and the document is moved closer to the downstream in the document conveying direction. In the case where the document is conveyed so as to increase the conveyance speed, or in the same configuration as that shown in FIG. 1, the document conveying means removes the document from the document tray at the first reading position A (see FIG. 1) or second. A sheet conveyed to a reading position B (see FIG. 1), a sheet document placed with the front side facing up, separated one by one, reversed while being fed, moved to a predetermined position on the contact glass, and first read A sheet mode for reading an image of an original by means, and a book mode for reading an original while placing a thick original such as a book original on a contact glass and moving the first reading means along the original In the sheet mode of the document reading apparatus provided so as to be selectable, the second reading means for reading the opposite surface of the document is arranged in the conveyance reversal portion of the document, similar to that shown in FIG. In this configuration, the sheet originals placed with the image surface facing up are separated one by one, reversed while being fed, moved to a predetermined position on the contact glass, and the original image is obtained by the first reading means. A sheet mode for reading and a book mode for reading a document while placing a thick document such as a book document on the contact glass and moving the first reading means along the document are selectable. In the case where a paper discharge tray which is a discharge destination also functions as the book mode pressure plate, and which is configured in the same manner as that shown in FIG. A part of the document conveying means for separating the sheets one by one is composed of FRR (Feed & Reverse Roller), and the same structure as that shown in FIG. Reduction of illumination, a plurality of mirrors, lenses, and photoelectric conversion means as one unit in a part of the document conveying means to be separated is composed of a friction pad, or is constructed similarly to that shown in FIG. 1. An optical system that scans a document placed on a contact glass, a device that is configured in the same manner as that shown in FIG. There is one that is conveyed linearly without passing through the position twice, and the other side of the original is read after one side of the original is read, and is not limited to the above.

1 is a schematic overall configuration diagram of an embodiment of a document reading apparatus according to the present invention. 1 is a partial schematic configuration diagram of a document reading apparatus according to an embodiment 1 is a partial schematic configuration diagram of a document reading apparatus according to an embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Document reading apparatus 5 Document conveying means 6 1st single-sided reading means 33 2nd single-sided reading means 51 Original reading apparatus 55 Conveying speed inclination means 56 1st single-sided reading means 101 Original reading apparatus 105 Original conveying means 106 1st single-sided reading means

Claims (3)

Document conveying means for conveying the document such that a curve indicating the document conveyance path is a substantially inverted U-shaped curve;
A first one-side reading means for reading one side of the document;
A second single-sided reading unit that is provided to face the first single-sided reading unit across the curve, and reads the other side of the document;
With
The first single-side reading unit reads one side of the original and the second single-side reading unit while the original conveying unit conveys the original so that the curve becomes a substantially inverted U-shaped curve. A document reading apparatus that reads both sides of the document by causing the other side of the document to be read.   2. The original document according to claim 1, wherein the original document conveying means comprises conveyance speed tilting means for conveying the original document so that the original document conveyance speed increases as the original document advances along the conveyance path. Reader.   3. The document reading apparatus according to claim 1, wherein the first single-side reading unit is detachably attached to the apparatus main body.