JP2006313995A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that it is difficult to make an image reading device compact because of a space needed in a sub scanning direction of the apparatus to provide a document carrying unit and the apparatus becomes expensive because of higher costs resulting from more components since the image reading apparatus which has a plurality of line sensors aligned in a zigzag shape to read an image of a large-sized document is constituted by providing a driving roller and a driven roller pressing a document 5 against the driving roller to hold the document before and behind an image reading section in the sub scanning direction and a document pressing member pressing the document carried on the image read section against a contact glass. <P>SOLUTION: The image reading apparatus is constituted by providing the document carrying means operated to the document having an image to be read to carry it in the sub scanning direction on both main-scanning-directional end sides of the plurality of image sensors aligned in the zigzag shape so as to be prescribed weight so that read pixels in the main scanning direction overlap with each other as specified. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image reading apparatus, and more specifically, a plurality of line sensors in which reading pixels are arranged in a row are arranged in a staggered manner in the main scanning direction, and the reading is carried in a sub-scanning direction orthogonal to the line sensor. The present invention relates to an image reading apparatus that sequentially reads a large-size original on which a power image is formed by the line sensor.

FIG. 11 is a diagram showing the configuration of an original conveying scanner which is this type of image reading apparatus. In the figure, 1 is a scanner body, 2 is sequentially 0, 1, 2,... In the main scanning direction of the figure. , N−1, N and a contact type image sensor in which a plurality of read pixels composed of photoelectric conversion elements are arranged in a row, 3 is a document conveying unit, 4 is a document pressing unit, 5 is a document, and 7 is a control unit. .
A base 11 serving as a frame of the scanner main body is formed to have a U-shaped cross-sectional view extending in the main scanning direction, and a plurality of contact-type images for reading large-sized original images such as A0 and A1. Sensors S1, S2, S3,... Are arranged in two rows in a staggered manner so as to be separated by an interval l in the sub-scanning direction. A contact glass 12 made of a transparent glass member or the like is provided on the base 11, and the base 11, the contact type sensor 2, and the contact glass 12 constitute an image reading unit.
At the front and rear portions of the image reading unit in the sub-scanning direction, a driving roller 31 to which a rotational driving force is transmitted by a rotational driving mechanism (not shown), and a pinch roller that is a driven roller that presses against the driving roller 31 and sandwiches the document 5. A document conveying section 3 constituted by 32 is provided.
When reading an original image with this image reading apparatus, first, the original 5 is inserted between a driving roller 31 and a pinch roller 32 provided on the upstream side in the sub-scanning direction, and is sandwiched between them. The document 5 is conveyed in the sub-scanning direction by being driven to rotate in the direction of the arrow. In synchronization with the conveyance of the document 5, the document 2 is sequentially read by the sensor 2, stored in the line buffer 72 as data for each line in the main scanning direction, and the frame memory 73 read out from the line buffer 72. The image data of the entire document 5 is generated by combining the data for each line by shifting the separation distance (l) of each sensor in the sub-scanning direction.
The created image data of the document 5 is transmitted to a host device such as a computer via the interface circuit 74.

In the contact image sensor 2 used in this image reading apparatus, the light beam emitted from the light source 21 is reflected from the document 5 and is incident on the lens array 22 and forms an image on the line sensor 23. In order to perform good image reading, it is indispensable that the document 5 is conveyed in close contact with the contact glass 12. Therefore, in this type of document conveying type image reading apparatus, a document pressing unit 4 that presses the document 5 conveyed on the image reading unit against the contact glass 12 is provided, whereby the document 5 is directed in the direction of the contact glass 12. It is comprised so that it may urge and stick.
In this document pressing mechanism, a pressing member 40 made of a plate member having the same plane as the contact glass 12 is fixed in the main scanning and sub-scanning directions in order to bring the document 5 into close contact with the contact glass 12. This is made to act from directly above, and its own weight is used as a pressing force.
JP 2003-125159 A

In this type of image reading apparatus that reads a large document image by arranging a plurality of line sensors in a staggered pattern, the driving roller 31 and the document 5 are placed on the front and rear portions of the image reading unit in the sub-scanning direction as described above. A pinch roller 32, which is a driven roller that is pressed and clamped, is provided, and a document pressing member 4 that closely contacts the document 5 conveyed on the image reading unit to the contact glass 12 is provided. A space for providing a document transport mechanism in each direction is required, which makes it difficult to reduce the size of the apparatus, and increases the number of parts, which increases production costs and makes the apparatus expensive. Such a problem occurred.
On the other hand, the applicant of the present application, in Japanese Patent Application No. 2005-084844 filed earlier, has a staggered conveying means composed of a driving roller and a pinch roller that acts on the original and conveys it in the sub-scanning direction. An image reading apparatus has been proposed which is arranged in a staggered manner in a region having an opposite phase to the arrayed image sensors.
FIG. 12 is a view showing an image reading apparatus filed earlier, and a plurality of contact image sensors 2 are attached to a top cover member 6 that is rotatably attached to an image reading apparatus main body and is provided so as to open and close. Two rows are arranged in a staggered manner so as to be separated by an interval l in the sub-scanning direction, and the image reading apparatus main body 1 is extended in the main scanning direction corresponding to the close contact type image sensor 2 and is mutually sub-scanned. Two drive rollers 81 that are spaced apart from each other by a distance l in the scanning direction, and a staggered pattern so as to be in opposite phase to the contact type sensor 2 so that the top cover member 6 is in pressure contact with the drive roller 81 in a closed state. A document conveying mechanism 8 constituted by a plurality of driven rollers 82 arranged in the above is provided.
When the document is transported (document image reading operation), the top cover member 6 is closed, whereby the document is held between the driving roller 81 and the driven roller 82, and the two driving rollers 81 are rotationally driven in this state. Thus, the original is conveyed in the sub-scanning direction.
According to the image reading apparatus previously filed, the space for providing the document conveying mechanism in the front and rear portions of the image reading portion in the sub-scanning direction, which has been conventionally required, is no longer required, and the apparatus can be miniaturized.

In the document conveying section in the image reading apparatus previously filed, the driven roller provided in the staggered area of the image reading section composed of the image sensor arranged in a staggered pattern is opposite in phase to the image sensor. Since a plurality of roller members are arranged in parallel in the entire area, there is a problem that the number of parts increases as a whole, thereby increasing the manufacturing cost. In order to solve this problem, the driven roller provided in the staggered region having the opposite phase to that of the image sensor is composed of a single roller that covers the entire region, and the total number of parts is reduced. In this case, a gap extending in the main scanning direction is formed between the driven roller and the cover member. For example, when reading an image such as a thin original with a curl Therefore, there is a new problem that the original enters the gap between the driven roller and the cover member and causes a jam phenomenon during conveyance.
The present invention has been made to solve these problems.

  In the image reading apparatus of the present invention, the document conveying means that acts on the document to be read and conveys it in the sub-scanning direction is arranged in two rows in a staggered manner so that the read pixels overlap by a predetermined amount in the main scanning direction. Each of the plurality of image sensors is provided at both ends in the main scanning direction.

  According to the image reading apparatus of the present invention, it is possible to carry the document well, and to reduce the number of parts and to produce the apparatus at low cost.

  A plurality of document conveying means composed of a driving roller and a driven roller pressed against each other via a document on which an image to be read is formed are arranged in two rows in a staggered manner so that a predetermined number of read pixels overlap in the main scanning direction. Each image sensor is provided on both sides in the main scanning direction.

The image reading apparatus of the present invention will be described below with reference to the drawings.
1 to 3 are views showing an image reading apparatus according to the present invention. Components identical to those of the above-described conventional apparatus and the previously filed apparatus are given the same reference numerals.
In the figure, reference numeral 6 denotes a top cover member that is rotatably attached to the image reading apparatus main body 1 and is provided so as to open and close. In this embodiment as well, the top cover member 6 is the same as the apparatus of the previous application. A contact image sensor 2 is provided. This configuration has an effect that the operator can confirm the side on which the image to be read of the document 5 is formed during the image reading operation of the document 5. Similar to the conventional apparatus, the contact image sensor 2 may be provided on the image reading apparatus main body 1 side.
As shown in the figure, also in the image reading apparatus of the present invention, a plurality of contact image sensors 2 are arranged in two rows in a staggered manner with a distance l in the sub-scanning direction. Thus, the image can be read in the full width region in the main scanning direction.

The document conveying means 8 in the image reading apparatus of the present invention is composed of a driving roller 81 provided on the image reading apparatus main body 1 side and a driven roller 82 provided on the cover member 6 side. The driving rollers 81 are arranged in a staggered manner on the two rotating shafts 810 provided apart from each other in the sub-scanning direction by an interval l so as to correspond to the contact image sensor 2, and the driven roller 82. Are respectively provided at both ends of the contact image sensor 2 in the main scanning direction.
When the cover member 6 is closed, the driven rollers 82 provided at both ends in the main scanning direction of each image sensor come into contact with the driving roller 81 (upper view in FIG. 2). In this embodiment, the driven roller 82 is fixed and supported so as to be rotatable with respect to the top cover member 6, and the driving roller 81 provided on the image reading apparatus 1 side includes the image sensor 2 and the driven roller. It is configured to be urged in the direction of the image sensor 2 and the driven roller 82 at all times by a pressure unit 83 that is supported so as to be movable in the direction of 82, and that abuts against this.
As shown in FIG. 3, both end portions of the rotation shaft 810 of the driving roller 81 provided so as to extend in the main scanning direction are inserted into sliding grooves 131 formed in the side plate 13 provided in the scanner body 1. The drive roller 81 is supported along the sliding groove 131 so as to be movable in the Z-axis direction in the drawing, that is, in the direction toward the image sensor 2 and the driven roller 82. The pressure unit 83 that acts on the driving roller 81 includes an arm 832 that is rotatably attached to the scanner main body 1, a roller 831 that is rotatably attached to the arm 832, and an arm 832 that acts on the roller 832. A compression spring 833 that is brought into pressure contact with 81 is configured such that the driving roller 81 is constantly urged in the direction of the image sensor 2 and the driven roller 82 by the restoring force of the compression spring 833. When the driving roller 81 is rotationally driven by a rotational driving means including a motor and a transmission mechanism (not shown), the roller 831 pressed against the driving roller 81 is driven so that the pressure unit 83 is loaded with respect to the rotational driving of the driving roller 81. In other words, the driving roller 81 is biased in the direction of the image sensor 2 and the driven roller 82.

When the document 5 is conveyed (document image reading operation), as shown in FIG. 2, when the cover member 6 is closed, the document 5 is sandwiched between the driving roller 81 and the driven roller 82. In this state, the two drive rollers 81 are rotationally driven in synchronization by a drive motor (not shown) and its rotational driving force transmission mechanism, whereby the document 5 is conveyed in the sub-scanning direction.
According to the present embodiment, the document 5 is sandwiched between the driven roller 82 arranged on both ends of the image sensor 2 in the main scanning direction and the driving roller 81 pressed against (via the document 5) the driving roller 82. In the contact-type image sensor 2, the surface of the image sensor 2 (contact glass) and the document 5 is moved when the document 5 is sandwiched between the driving roller 81 and the driven roller 82. A predetermined gap, that is, a gap is formed between the two (FIG. 2 lower figure). That is, in the cover member 6, the position where the driven roller 82 is attached is positioned and fixed so that the height differs in a position closer to the driving roller 81 than the image sensor 2 (contact glass), in the vertical direction shown in the figure. Thus, the predetermined gap is formed. As a result, according to the present embodiment, for example, a sensor that can be used as the image sensor 2 that allows a certain depth in the depth of focus can be adopted as the characteristic of the sensor, and the sub-scanning direction can be used in the image reading unit. The document 5 is supported by the driven rollers 82 arranged in a zigzag pattern on two driving rollers 81, so that the document 5 can be pressed and supported in a substantially two-dimensional plane. The document 5 can be reliably conveyed between the allowable depth of focus, that is, a predetermined gap (gap) in the drawing, and good image reading can be performed.
Further, in this embodiment, means for urging the two driving rollers 81 provided on the upstream side and the downstream side of the conveyance path of the document 5 in the direction of the image sensor 2 and the driven roller 82 are provided independently. Accordingly, even if the original is not constant in the sub-scanning direction, such as a large drawing having a hanger, the relative distance between the image sensor 2 and the image reading surface of the original 5 is always constant, that is, close contact It is possible to position the image reading surface of the document 5 at the focal length of the mold sensor 2, thereby achieving an effect that good image reading can be performed.
As shown in FIG. 2, the document 5 is inserted into the image reading unit, brought into contact with the driving roller 81 and the driven roller 82 on the upstream side in the transport direction (sub-scanning direction), and the driving roller 81 is further driven by driving means (not shown). When driven to rotate, the document 5 is sandwiched between the driving roller 81 and the driven roller 82 (the figure in FIG. 2). At this time, the driven roller 82 is supported so as to be fixed to the cover member 6. The drive roller 81 rotates the arm 832 against the restoring force of the compression spring 833 of the pressure unit 83 in the direction of the arrow in the drawing, and the original so that the rotation drive shaft 810 of the drive roller slides in the slide groove 131. It is pushed down by the thickness of 5.
In this state, the driving roller 81 is rotated to convey the document 5 in the sub-scanning direction, and the document image is read by the image sensor 2 provided on the upstream side (on the conveyance path of the document 5).
When the document 5 is transported and the image sensor 2 reads the image sequentially, the leading end portion of the document 5 comes into contact with the driving roller 81 and the driven roller 82 on the downstream side in the sub-scanning direction, and is further transported. The driving roller 81 is pushed down against the restoring force of the compression spring 833 and is sandwiched between the driving roller 81 and the driven roller 82 on the downstream side of the conveyance path. (Figure 2 bottom)
At this time, the drive roller 81 on the upstream side of the conveyance path slides in the direction of the driven roller 82 and the image sensor 2 following the thickness of the document 5 (along the sliding groove 131). The distance between the image reading surface and the image sensor 2 is configured to be constant without depending on the change in the thickness of the document. Further, as shown in the lower diagram of FIG. 2, the driving rollers 81 provided on the upstream side and the downstream side of the document transport path are provided so as to be independently slidable, so that the thickness of the document 5 is not constant in the sub-scanning direction. Even in this case, the relative distance between the image sensor 2 and the image reading surface of the document 5 is configured to be always constant.
As described above in detail, in the image reading apparatus of the present invention, the driving roller and the driven roller that are pressed against each other via the document are provided on both ends in the main scanning direction of each image sensor arranged in two rows in a staggered manner. Since the document is sandwiched and conveyed, the number of use points of the roller member can be reduced, and the apparatus can be manufactured at low cost.

4 and 5 show the first embodiment of the present invention described above, in which the downstream driving roller 81 is located when the original 5 is sandwiched between the upstream driving roller 81 and the driven roller 82 in the original conveying direction. It is configured such that a gap is formed between the driven roller 82 and the driven roller 82 by pressing down a certain amount.
In the second embodiment, link mechanisms 84 that engage with the rotation shafts 810 of the respective drive rollers 81 upstream and downstream in the document transport direction are provided at both ends in the main scanning direction. The link mechanism 84 includes a plate 840 in which grooves 841 and 842 are formed, a rotary shaft 843 that rotatably supports the plate 840 on the side plate 13 of the scanner body 1, and a tension spring 844 that constantly biases the plate 840. It is comprised by.
As shown in FIGS. 4 and 5, the groove 841 formed in the plate 840 is formed so as to engage with the lower side of the rotation shaft 810 of the driving roller 81 provided on the upstream side of the conveyance path of the document 5. The plate 840 is formed so as to follow down when the document 5 is held down, and the groove 842 is formed so as to engage with the upper side of the rotation shaft 810 of the downstream drive roller 81. Has been. The tension spring 844 always urges the plate 840 upward about the rotation shaft 843, that is, the drive roller 81 on the upstream side of the document conveyance path (in the same manner as the pressure unit 83) in a direction in pressure contact with the image sensor 2 and the driven roller 82. It is provided as follows. (Upper figure of Figure 4)
In the image reading apparatus according to the second embodiment, when the document 5 is inserted into the image reading unit and sandwiched between the upstream driving roller 81 and the driven roller 82, the thickness of the document 5 is shown in FIG. Accordingly, when the upstream drive roller 81 is pushed down, the plate 840 engaged with the rotating shaft 810 is pushed down against the restoring force of the tension spring 844 and engaged with the groove 842 of the plate 840. The downstream drive roller 81 (rotation shaft 810) is also pushed down, thereby releasing the pressure contact between the downstream drive roller 81 and the driven roller 82, and forming a gap therebetween.
Further, when the document 5 is sequentially conveyed and the leading end reaches the downstream driving roller 81 and the driven roller 82, the document 5 is inserted into the formed gap, and the downstream driving roller 81 has the thickness of the document 5. In response, the plate 840 is disengaged and pushed down. (Figure 4 bottom)
By configuring as in the second embodiment, the impact when the document 5 is inserted between the driving roller 81 and the driven roller 82 on the downstream side can be reduced as compared with the case where they are pressed against each other. Therefore, it is possible to prevent a jamming phenomenon (a conveyance failure state in which the document is folded in a complicated manner) caused by the document colliding with the downstream driving roller 81 and the driven roller 82 that are pressed against each other and further transporting the document. It becomes possible.

In the above-described embodiment, the document guide 14 that guides the document 5 when the document 5 is conveyed is provided to be fixed to the image reading apparatus main body 1, but the drive roller 81 is displaced according to the thickness of the document 5. You may comprise so that it may track.
6 and 7 show the document guide 14 configured to follow the displacement of the drive roller 81 according to the displacement of the drive roller 81. The document guide main body 140 having a hole 141 formed so that the drive roller 81 protrudes from the document guide main body 140. The side plate 142 is provided at both ends in the main scanning direction and into which the rotational drive shaft 810 of the drive roller 81 is rotatably inserted.
As shown in FIG. 6, when the document 5 is inserted into the image reading unit and is sandwiched between the driving roller 81 and the driven roller 82 on the upstream side in the conveyance direction, the upstream driving roller 81 is pushed down according to the thickness of the document 5. At the same time, the document guide 14 is pushed down in synchronism with this (FIG. 6). When the document 5 is conveyed in the sub-scanning direction by driving the drive roller 81, the leading end reaches the drive roller 81 and the driven roller 82 on the downstream side, and further pushes down the drive roller 81, whereby the document 5 Is sandwiched between the driving roller 81 and the driven roller 82 (the lower diagram in FIG. 6).
Thus, by providing the document guide 14 together with the driving roller 81 so as to be displaced according to the thickness of the document 5, the document guide 14 is sandwiched only by the upstream driving roller 81 and the driven roller 82 shown in FIG. The leading edge portion of the document 5 is prevented from colliding with the document guide 14 (the main body 140) from when the document is held between the downstream driving roller 81 and the driven roller 82 shown in the lower diagram of FIG. Is possible. Thus, it is possible to prevent an image reading failure by the upstream sensor 2 that occurs when the leading end of the document 5 collides with the document guide 14 during conveyance.

In the embodiment described above, the driving rollers 81 are arranged in two rows in a staggered manner corresponding to the image sensors arranged in two rows in a staggered manner and the driven rollers 82 provided at both ends in the main scanning direction. Although configured as described above, as shown in FIG. 8, it may be configured by two rollers separated from each other by an interval l in the sub-scanning direction.
Further, in the above-described embodiment, the driven rollers 82 provided on both sides of each image sensor 2 are fixed and supported so as to be rotatable with respect to the cover member 6, and the driven roller 82 and the driving roller 81 (document 5 When the surface is pressed against the image sensor 2 (contact glass), a predetermined gap or gap is formed between the drive roller 81 (the surface of the document 5) and the drive roller. The gap between the image sensor 2 and the image sensor 2 is set to 0, and the document 5 is configured to be pressed against the image sensor 2 by the driving roller 81, thereby providing the document 5 to be brought into close contact with the contact glass of the image sensor 2. Also good.

FIG. 9 is a diagram showing the conveyance when the original 5 having the width of one image sensor 2 is read in the image reading apparatus of the present invention. In this case, the image sensors 2a, 2c, 2e on the upstream side in the original conveyance direction. Of these, the center image sensor 2c is used as a reference, that is, the center portion in the main scanning direction is set as a reference for document conveyance, and the operator sets the document 5 so that the center of the document 5 is aligned with the center of the image sensor 2c. (Upper figure in FIG. 9). At this time, when the document 5 is sandwiched between the pinch roller 82 and the driving roller 81 (not shown) on both sides of the image sensor 2c in the main scanning direction, and the driving roller 81 is rotationally driven by a rotational driving means (not shown), the document 5 is When it is conveyed in the sub-scanning direction and its leading end abuts on the driven roller 82 (and drive roller 81) disposed on one side of each of the image sensors 2b and 2d on the downstream side of the document conveyance path, and further conveyed, As shown in the figure in FIG. 9, the image sensor 2c is nipped by the drive roller 81 at a total of four locations, the driven roller 82 on both ends of the image sensor 2 and the driven roller 82 on one side of each of the image sensors 2b and 2d.
While being held between these four points, the document 5 is transported satisfactorily. However, the document 5 is sequentially transported so that the rear end in the sub-scanning direction of the document 5 holds the driven rollers 82 on both sides of the upstream image sensor 2c. If removed, as shown in the lower diagram of FIG. 9, the portion where the document 5 is sandwiched is consequently biased toward the center portion in the main scanning direction.
When the document 5 is conveyed, the document 5 is rotated in the rotation direction around this portion in the state where only the central portion in the main scanning direction is sandwiched between the driven rollers 82 on one side of each of the image sensors 2b and 2d. It becomes easy to do and will be in an unstable state. As a result, inconveniences such as a conveyance failure such as a jam phenomenon and a deterioration in the quality of a read image may occur.
In order to solve this problem, in the third embodiment of the present invention, with respect to the image sensors arranged in two rows in a staggered manner, the arrangement intervals of the image sensors in the main scanning direction between the upstream side and the downstream side in the document conveyance direction. Were provided differently.
FIG. 10 is a diagram showing a third embodiment of the present invention. In the first embodiment, the arrangement interval of the image sensors in the main scanning direction is constant, whereas in the third embodiment, FIG. Is characterized in that the arrangement interval D of the sensors on the downstream side is made larger than the arrangement interval C of the sensors on the upstream side in the document conveyance (sub-scanning) direction.
That is, in the third embodiment of the present invention, of the image sensors 2a, 2c and 2e on the upstream side in the document transport direction, the center image sensor 2c is used as a reference, that is, the center portion in the main scanning direction is transported. The region A overlapping with the read pixels of the image sensor 2c serving as the reference is reduced so that the image sensors 2b and 2d on the downstream side in the document conveyance (sub-scanning) direction are set apart as the reference and are separated in the both sides of the main scanning. Arrange. As a result, a region B where the read pixels of the image sensors 2a and 2b and 2d and 2e overlap is larger than the region A.
Thus, by making the arrangement interval D of the image sensors 2d and 2e downstream in the document transport direction larger than the arrangement interval C on the upstream side, the separation distance of the driven rollers 82 provided on both sides of each sensor 2 is also increased. Therefore, even when the document 5 having a small width is read, both end portions of the document 5 can be held between the driven roller 82 and the driving roller 81 on the downstream side in the document transport direction. Therefore, even if the document 5 is sequentially transported and the rear end portion in the sub-scanning direction is unpinched between the upstream driving roller 81 and the driven roller 82 (lower view in FIG. 10), the downstream driving roller 81 and the driven roller 82 are removed. Thus, since both end portions of the document 5 are sandwiched, there is an effect that the conveyance is not unstable and good image reading can be performed.
Therefore, according to the third embodiment, it is possible to satisfactorily convey a large original to a narrow original.
In the above embodiments, the document conveyance reference is the central sensor upstream in the document conveyance direction. However, the reference may be set to any sensor, and may be configured to be set to any of the upstream and downstream sides. .

1 is a perspective view illustrating a configuration of an image reading apparatus of the present invention. 1 is a cross-sectional view illustrating a configuration of an image reading apparatus of the present invention. It is a figure which shows the drive roller part of the image reading apparatus of this invention. It is sectional drawing which shows the structure of 2nd Example of this invention. It is a figure which shows the drive roller part of 2nd Example of this invention. FIG. 6 is a cross-sectional view showing another configuration of the document guide in the image reading apparatus of the present invention. It is a figure which shows another structure of the document guide in the image reading apparatus of this invention. It is a figure which shows another structure of the drive roller part in the image reading apparatus of this invention. FIG. 6 is a diagram illustrating a document conveyance state by the image reading apparatus of the present invention. It is a figure which shows 3rd Example of this invention. It is a figure which shows the structure of the conventional image reading apparatus. It is a figure which shows the image reading apparatus of a previous application.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Scanner main body 2 Close contact type image sensor 3 Document conveyance part 4 Document press part 5 Document 6 Top cover part 7 Control part 8 Document conveyance part

Claims (13)

A plurality of image sensors arranged in two rows in a staggered manner so that the read pixels overlap by a predetermined amount in the main scanning direction, and original conveying means that acts on the original and conveys it in the sub-scanning direction, In an image reading apparatus that creates image data of an entire document from image data obtained from an image sensor,
The image reading apparatus, wherein the document conveying means is provided at both ends of each image sensor in the main scanning direction. The image reading apparatus according to claim 1.
The image reading apparatus, wherein the document conveying means is configured so that a driving roller and a driven roller provided so as to come into pressure contact with each other via the document are arranged on both sides of the image sensor in the main scanning direction.   3. The document conveying means includes a driven roller arranged on both sides of the image sensor in the main scanning direction, and a driving roller provided so as to be in pressure contact with the driven roller via the document. The image reading apparatus described in 1. The image reading apparatus according to claim 3.
An image reading apparatus characterized in that a driving roller of the document conveying means is constituted by two rollers disposed in the main scanning direction so as to face the image sensor and the driven roller arranged in a staggered manner. The image reading apparatus according to claim 3.
The driving roller of the document conveying means is constituted by a plurality of rollers having two straight axes extending in the main scanning direction facing the image sensor and the driven roller arranged in a staggered manner as rotation axes. Reader.   6. A predetermined gap is formed between the original and the image sensor when the driven roller and the driving roller of the original conveying unit are pressed against each other via the original. Image reading device.   6. The image reading according to claim 3, wherein when the driven roller and the driving roller of the document conveying unit are pressed against each other via the document, the driving roller presses the document in the direction of the image sensor. apparatus.   3. The document conveying means includes a driving roller arranged on both sides of the image sensor in the main scanning direction, and a driven roller provided so as to come into pressure contact with the driving roller via the document. The image reading apparatus described. The image reading apparatus according to claim 1 or 2,
An image reading apparatus, comprising: a pressing unit that acts on a document conveyed in the sub-scanning direction by the document conveying unit and presses the document toward the image sensor.   When the driving roller and the driven roller on the upstream side of the document conveying path of the document conveying means are pressed against each other via the document, the pressure contact is released against the pressing force of the pressing means acting on the downstream driving roller and the driven roller. 10. The image reading apparatus according to claim 9, further comprising means for performing the operation.   A document conveying means that guides the conveyance of the document and that displaces against the pressing force of the pressing means according to the thickness of the document when the driving roller and the driven roller of the document conveying means are pressed against each other via the document; 11. The image reading apparatus according to claim 9, further comprising a document guide configured to be displaced in synchronization. The image reading apparatus according to claim 1 or 2,
An image reading apparatus, wherein an arrangement interval of each image sensor in the main scanning direction is provided to be different between an upstream side and a downstream side in a document conveying direction.   13. The image sensor according to claim 12, wherein two image sensors in which a reading pixel overlaps the image sensor are arranged so as to be separated from each other in both main scanning directions with respect to at least one image sensor on one side of the document conveyance direction. Image reading device.

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