JP2018157569A - Image reading device and copying machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading device and a copying machine, which allow a transfer mode suitable for size of a document to be selected.SOLUTION: An image reading device has a long-size mode for reading a long document having length in a transfer direction exceeding predetermined length. Depending on whether the device is in the long size mode or not, document transfer is permitted when the device is in the long size mode and in a state of "corner guide" where the long document placed on a side of a guide wall lateral to the document tray is transferred by being guided by the guide wall, and document transfer is permitted when the device is not in the long size mode and in a state of "center guide" where the document placed on the document tray at a place near the center in a width direction of the document tray by a pair of guide members is transferred by being guided by the pair of guide members.SELECTED DRAWING: Figure 12

Description

  The present invention relates to an image reading apparatus and a copying machine.

  Patent Document 1 discloses a document reading apparatus that selects whether correction of document inclination is executed according to image quality settings.

  Further, Patent Document 2 discloses an image reading apparatus that includes a document length measuring unit and determines whether or not to perform document inclination correction based on the document length measured by the document length measuring unit. ing.

JP 2010-021832 A JP 2010-206696 A

  An object of the present invention is to provide an image reading apparatus and a copying machine in which a conveyance mode suitable for the size of a document is selected.

Claim 1
A table on which a document on which an image is formed is placed;
A guide wall that stands up along one side edge in the width direction intersecting the conveyance direction of the document placed on the placement table and guides the conveyance of the document in contact with the side edge of the document; and A pair of guides that are movable in opposite directions in the width direction and that sandwich the document placed on the mounting table from both sides in the width direction and bring the document toward the center in the width direction of the mounting table. A document placing portion having a member;
A document transport unit that sequentially transports the documents placed on the mounting table one by one and passes the reading position;
An original reading unit that reads an image on an original passing through the reading position;
A long mode for reading a long document whose length in the transport direction exceeds a predetermined length; and
In the case of the long mode, the long original is placed at a position close to the guide wall on the mounting table according to whether the long mode is set or not. The document is allowed to be conveyed when in the first conveyance mode in which it is conveyed while being guided, and when not in the long mode, the document is moved to the center in the width direction on the table by the pair of guide members. An image reading apparatus comprising a document conveyance permission / rejection unit that permits document conveyance when in a second conveyance mode in which the document is conveyed while being guided by the pair of guide members. is there.

Claim 2
A first inclination correction unit that is disposed upstream of the reading position of the original transported by the original transport unit and corrects the inclination of the original in response to abutment of the leading end of the transported original;
A correction mode switching unit that switches between a first correction mode that operates the first inclination correction unit and a second inclination correction unit that does not operate the first inclination correction unit;
The document conveyance permission / rejection unit is not limited to the first conveyance mode and the second conveyance mode when the correction mode switching unit is switched to the first correction mode even in the long mode. The image reading apparatus according to claim 1, wherein the image reading apparatus is allowed to convey a document when the document is in any of the above.

Claim 3
A tilt amount of an image represented by the image signal is calculated based on the image signal generated by the document reading unit, and a new image signal representing an image whose tilt is corrected is generated based on the calculated tilt amount. A second inclination correction unit;
3. The image reading according to claim 2, wherein the correction mode switching unit selectively switches between tilt correction by the first tilt correction unit and tilt correction by the second tilt correction unit. Device.

Claim 4
The guide wall includes a storage unit that stores the first guide member and enables the guide wall to guide the document;
The pair of guide members store the first guide member in the storage portion, and move only the second guide member of the pair of guide members excluding the first guide member in the width direction. The first movement mode and the second movement mode in which the first guide member and the second guide member are moved in opposite directions in the width direction of the mounting table are switchable members. The image reading apparatus according to claim 1, wherein the image reading apparatus is an image reading apparatus.

Claim 5
4. The first guide member according to any one of claims 1 to 3, wherein the first guide member is detachable from the mounting table at a position where the first guide member is brought close to the guide wall. An image reading apparatus.

Claim 6
An image reading apparatus according to any one of claims 1 to 5,
An image forming apparatus that forms an image on a sheet based on an image signal generated by the image reading apparatus.

  According to the image reading apparatus of the first aspect and the copying machine of the sixth aspect, the transport mode suitable for each is selected depending on whether or not the document is a long document.

  According to the image reading apparatus of the second aspect, the restriction on a long document is relaxed.

  According to the image reading apparatus of the third aspect, the inclination correction is always performed.

  According to the image reading apparatus of the fourth aspect, the transfer mode can be easily switched.

  According to the image reading apparatus of the fifth aspect, it can be clearly seen which transport mode is in effect.

1 is a block diagram of a multifunction machine including an image reading apparatus and a copier as an embodiment of the present invention. FIG. 2 is a schematic diagram mainly showing a mechanical configuration of the multifunction machine shown in the block diagram of FIG. 1. FIG. 3 is a perspective view showing an upper part of the outer appearance of the multifunction machine shown in FIG. 2. FIG. 3 is an operation explanatory diagram of the image reading apparatus shown in FIGS. 1 and 2. It is explanatory drawing of the processing content of an image inclination correction process. FIG. 2 is a perspective view showing an upper part of the image forming apparatus. FIG. 3 is a view showing an inside of an image reading apparatus when an opening / closing cover is opened. It is the figure which showed the 1st example of the switching structure which implement | achieves switching with a center guide and a corner guide. It is the figure which showed the 2nd example of the switching structure which implement | achieves switching with a center guide and a corner guide. It is the figure which showed the correction | amendment switching setting screen. It is a diagram showing a long document setting button. FIG. 4 is a flowchart illustrating a first example of an operation sequence of the image reading apparatus included in the multifunction peripheral according to the present embodiment when a start button illustrated in FIG. 3 is pressed. 4 is a flowchart showing a second example of an operation sequence of the image reading apparatus when a start button shown in FIG. 3 is pressed.

  Embodiments of the present invention will be described below.

  FIG. 1 is a block diagram of a multifunction machine including an image reading apparatus and a copying machine as an embodiment of the present invention.

  The multifunction machine 1 includes an image reading device 10 and an image forming device 20.

  In the image reading apparatus 10, an image on a document is read to generate an image signal, and the image signal is input to a signal processing unit 30 described later and subjected to various signal processing. In the image reading apparatus 10, an original on which an image to be read is recorded is conveyed on a conveyance path that passes through a reading position, and an image on the original is read when the original passes through the reading position. The image reading device 10 corresponds to an example of the image reading device according to the present invention. Details will be described later.

  In the image forming apparatus 20, an image based on the image signal is formed on a sheet, and the sheet P on which the image is formed is discharged from the image forming apparatus 20. Here, a so-called electrophotographic image forming apparatus is taken into consideration, but the image forming apparatus 20 does not have to be an electrophotographic system, and may be an ink jet type or other type of image forming apparatus. .

  The image formed on the paper P by the image forming apparatus 20 does not necessarily need to be an image signal obtained by reading an image on a document by the image reading apparatus 10, as will be described below. It may be an image signal input from the outside.

  The multifunction machine 1 includes a signal processing unit 30. In the signal processing unit 30, various signal processes corresponding to the mode are performed on the image signal obtained by the image reading apparatus 10 and the image signal input from the outside.

  Further, the multifunction device 1 is provided with an I / O interface 40 and a FAX interface 50.

  The I / O interface 40 is responsible for communication between the multifunction device 1 and an image editing apparatus (not shown) typically constituted by a computer. The I / O interface 40 receives the image signal obtained by the image reading device 10 via the signal processing unit 30 and transmits it to the image editing device. In this case, the multifunction device 1 has a function as a scanner. The I / O interface 40 receives an image signal transmitted from the image editing apparatus. The image signal received by the I / O interface 40 is sent to the image forming apparatus 20 via the signal processing unit 30. The image forming apparatus 20 forms an image on a sheet based on the sent image signal. In this case, the multifunction device 1 has a function as a printer.

  The FAX interface 50 is a module that is connected to a telephone line and performs a facsimile function. That is, in the FAX transmission mode, a document on which an image for facsimile transmission is recorded is read by the image reading apparatus 10 to generate an image signal, and the generated image signal passes through the signal processing unit 30 and the FAX interface 50. Then, it is sent to the telephone line toward the receiver. In the FAX reception mode, an image signal transmitted through a telephone line is received by the FAX interface 50 and input to the image forming apparatus 20 via the signal processing unit 30. In the image forming apparatus 20, an image based on the input image signal is printed out on paper.

  Further, the multifunction device 1 has a copy function. In the copy mode, an image signal obtained by reading an original with the image reading apparatus 10 is input to the image forming apparatus 20 via the signal processing unit 30, and the image forming apparatus 20 performs an image based on the input image signal. Is printed on paper. This copy function corresponds to an example of a copying machine according to the present invention.

  Further, the multifunction device 1 includes a control unit 60. The control unit 60 includes a user interface 61. The control unit 60 is responsible for, for example, the above-described various functions and mode switching control in response to a user instruction from the user interface 61, and all other control necessary for the multifunction machine 1.

  Here, the signal processing unit 30, the I / O interface 40, the FAX interface 50, and the control unit 60 may be provided in the casing of the image reading apparatus 10 or in the casing of the image forming apparatus 20. Alternatively, the image reading apparatus 10 and the image forming apparatus 20 may be separately provided in the housing. As shown in FIG. 2, the multifunction device 1 described here is provided in a housing of the image forming apparatus 20. However, the user interface 61 is provided on the upper surface of the casing of the image forming apparatus 20 as shown in FIG.

  FIG. 2 is a schematic diagram mainly showing a mechanical configuration of the multifunction peripheral shown in the block diagram of FIG.

  FIG. 2 shows the structures of the image reading device 10 and the image forming device 20 in the multifunction machine 1 shown in FIG. The other elements shown in FIG. 1 (the signal processing unit 30, the I / O interface 40, the FAX interface 50, and the control unit 60) are a circuit unit 70 and are collectively shown as one block. However, the user interface 61 will be described separately with reference to FIG.

  The image reading apparatus 10 has a conveyance reading mode and a stationary reading mode as reading modes for reading an image on a document.

  In the transport reading mode, the document M placed on the document tray 11 is transported one by one in the direction of arrow S on the transport path indicated by the broken line, triggered by a user operation (pressing the start button 611 shown in FIG. 3). Pass through position SP. The image recorded on the document M is illuminated by the lamp 131 when passing through the reading position SP, and the reflected light passes through the reflecting mirrors 132, 133, 134 and the lens 135 constituting the reading optical system. Then, the image is guided to the reading sensor 136, and the image on the original M is read by the reading sensor 136 to generate an image signal. In the present embodiment, the light receiving device 13 is configured by the reading optical system including the reflecting mirrors 132, 133, 134 and the lens 135 and the reading sensor 136. The document M that has passed the reading position SP is discharged onto the document discharge tray 12. Details of the transport unit that transports the document M will be described later.

  The image reading apparatus 10 is provided with a transparent glass plate 14 on which one document is placed. In addition, the image reading apparatus 10 is provided with a hinge extending left and right on the back side in a direction perpendicular to the paper surface of FIG. 2, and has a structure in which the front side is lifted so that the upper part of the transparent glass plate 14 is opened.

  In the stationary reading mode, the document is lifted and the document M is placed on the transparent glass plate 14 downward, and the document is sandwiched between the transparent glass plate 14 and the lower surface of the document discharge tray 12. When reading is started by the user operation in this way, the lamp 131 and the mirrors 132 to 134 move in the direction of arrow D along the lower surface of the transparent glass plate 14, and the image on the original is read by the reading sensor 136. An image signal is generated.

  Next, an outline of the image forming apparatus 20 will be described.

  The image forming apparatus 20 is a type of apparatus that forms an image on a sheet P by a so-called electrophotographic system.

  The image forming apparatus 20 includes image forming units 21K, 21C, 21M, and 21Y that form toner images using toners of black (K), cyan (C), magenta (M), and yellow (Y). Is provided.

  Hereinafter, when it is not necessary to distinguish between the colors, the subscripts K, C, M, and Y representing the colors are omitted, and the description will be made with reference to numerals only.

  Each image forming unit 21 includes an electrophotographic photosensitive member 22 that rotates in the direction of arrow B. Each photoconductor 22 is charged by a charger (not shown), and an electrostatic latent image is formed on each photoconductor 22 upon exposure to exposure light from the exposure unit 23. Further, the electrostatic latent image is developed with toner by a developing device (not shown), and a toner image of each color is formed on each photoconductor 22.

  Under each image forming unit 21, an intermediate transfer belt 24 that is arranged along the arrangement of the photoreceptors 22, is stretched around a roll 241, and circulates in the direction of arrow A is provided. Further, each primary transfer roll 25 is disposed at a position facing each photoconductor 22 across the intermediate transfer belt 24.

  The toner images of the respective colors formed on the respective photoreceptors 22 are transferred so as to sequentially overlap on the intermediate transfer belt 24 by the action of the respective primary transfer rolls 25.

  Each image forming unit 21 is provided with a cleaner (not shown) for cleaning a region after transfer of the photosensitive member 22, and the surface of each photosensitive member 22 is cleaned by the cleaner.

  Further, the image forming apparatus 20 is provided with a secondary transfer roll 26, and the toner image transferred onto the intermediate transfer belt 24 is transferred onto the paper P conveyed to this position.

  Under the image forming apparatus 20, two paper trays 27A and 27B for storing paper are provided. In transferring the toner image onto the sheet P, one sheet P is taken out from either of the sheet trays 27A and 27B and is conveyed in the direction of arrow C by the conveying roll 271 and the position of the secondary transfer roll 26 is changed. Upon passing, the toner image on the intermediate transfer belt 24 is transferred. The paper P that has received the transfer of the toner image is further transported from the transport belt 272 and passes through the fixing device 28. The fixing device 28 includes a heating roll 281 and a pressure roll 282. The sheet P on which the unfixed toner image that has been conveyed is placed between the heating roll 281 and the pressure roll 282 is heated and heated. As a result, the unfixed toner image on the paper P is fixed on the paper P. The paper P on which the image composed of the fixing toner image is printed is discharged onto the paper discharge tray 29 by the discharge roll 273.

  The surface of the intermediate transfer belt 24 is cleaned by the cleaner 242 after the toner image on the intermediate transfer belt 24 is transferred onto the paper P by the action of the secondary transfer roll 26.

  FIG. 3 is a perspective view showing an upper part of the outer appearance of the multifunction machine shown in FIG.

  Here, the external appearance of the upper part of the image reading apparatus 10 and the image forming apparatus 20 is shown.

  The image reading apparatus 10 shown in FIG. 3 shows a document tray 11 and a document discharge tray 12 which are also shown in FIG. Also shown here is a guide member 117 that guides a document to be conveyed while regulating the position in the width direction of the document placed on the document tray 11. The document placed on the document tray 11 is restricted in position in the width direction by the guide member 117, and when a later-described start button 611 is pressed, the document is introduced from the document inlet 118 while being guided by the guide member 117. It is carried in one by one sequentially. An upper portion of the document carry-in port 118 is covered with an opening / closing cover 119 that is opened when the document is jammed.

  As described above, the image reading apparatus 10 has a structure in which the upper part of the line n shown in FIG. 3 is lifted up with the back side as a hinge, and in the lifted state, the transparent glass plate below it 14 (see FIG. 2), the original is placed face down, the raised upper part is closed again as shown in FIG. 3, and the start button 611 is pressed. Then, the image reading apparatus 10 reads an image on the document in the above-described still reading mode.

  Further, a user interface 61 (see also FIG. 1) is shown at the top of the image forming apparatus 20 shown in FIG.

  The user interface 61 shown in FIG. 3 includes the start button 611, a plurality of setting buttons 612 including a numeric keypad, and a touch panel 613 that also serves as a display.

  When the start button 611 is pressed, reading of a document in the image reading apparatus 10 is started. A setting button 612 is used to set the number of copies, the FAX number of the recipient at the time of FAX transmission, and the like. Furthermore, on the touch panel 613, various settings are performed according to the screen displayed there.

  FIG. 4 is a diagram for explaining the operation of the image reading apparatus shown in FIGS.

  The originals M placed on the original tray 11 are conveyed one by one on the conveyance path passing through the reading position SP in the direction of arrow S and discharged onto the original discharge tray 12.

  FIG. 5 shows a first roll 111, a second roll 112, a third roll 113, a fourth roll 114, a fifth roll 115, and a sixth roll 116 as conveyance members that carry the original M. Yes. As sensors for detecting the presence or absence of a document being conveyed on the conveyance path, a first sensor 121, a second sensor 122, a third sensor 123, a fourth sensor 124, a fifth sensor 125, and a sixth sensor 126 are provided. It is shown.

  This conveyance path has a function of correcting the inclination of the document M. However, when this document skew correction function is used, a louder sound is generated than when the document skew correction function is not used. Therefore, in this image reading apparatus 10, whether this document skew correction function is used or not is properly used. Here, the mode using the document skew correction state is referred to as a first correction mode, and the mode not using the document skew correction function is referred to as a second correction mode. Here, the document skew correction function will be described as being in the first correction mode using the document skew correction function.

  The first roll 111 is a roll that plays a role of feeding one of a plurality of documents M placed on the document tray 11 onto the conveyance path. The original M sent by the first roll 111 is stopped without rotating at the time when the leading end of the original M reaches the second roll 112. Therefore, the supplied original M is When the document is fed in a state of being tilted to the left and right, the tilt is corrected. Thereafter, the second roll 112 is also rotated, and the original M is further conveyed. The original M is further abutted against the third roll 113 and bent again, whereby the inclination of the original is corrected again. Thereafter, the document M is further fed by the third roll 113. However, the document M is conveyed with some curvature left between the second roll 112 and the third roll 113 so that the original M is not pulled due to the speed difference between the second roll 112 and the third roll 113. The The document conveyed by the third roll 113 is further conveyed by the fourth roll 114 and passes the reading position SP. At this reading position SP, the document M is conveyed in contact with the upper surface of the transparent glass plate 141. The document M that has passed the reading position SP is further conveyed by the fifth roll 115 and discharged onto the document discharge tray 12 by the sixth roll 116.

  The first sensor 121 to the sixth sensor 126 detect the passage of the document M that has been sent to the positions where these sensors are arranged, and thereby the timing of the start of rotation of the roll and the start of reading by the reading sensor 136. Etc. are adjusted. Regarding the timing of the reading start by the reading sensor 136, when the image inclination correction process (described later with reference to FIG. 6) on the image signal is performed, the timing adjustment of the reading start is particularly strict. However, precise timing adjustment is performed as compared to the case where the document inclination correction process described above is executed and the image inclination process is not performed on the image signal.

  Here, a reflecting member 137 is provided on the back side of the document M passing through the reading position SP, that is, at a position where the document M at the reading position SP is sandwiched between the lamp 131 and the document M.

  When the document M passes the reading position SP, the light emitted from the lamp 131 irradiates the document M, and the reflected light enters the light receiving device 13 and is read by the reading sensor 136 to generate an image signal. . The light receiving device 13 in this embodiment includes mirrors 132 to 134, a lens 135, and a reading sensor 136.

  The lamp 131 and the first mirror 132 are incorporated in the first carriage 13A, and the second mirror 133 and the third mirror 134 are incorporated in the second carriage 13B.

  Here, in the transport reading mode, that is, in the mode in which the document M is placed on the document tray 11, and the document M is transported by the first roll 111 and is read at the reading position SP, the first carriage 13 </ b> A and the second carriage 13. Reference numeral 13 </ b> B indicates that the document M conveyed to the reading position SP is irradiated with the lamp 131 while being stationary at the stationary position shown in FIG. 5, and the reflected light is read by the reading sensor 136. On the other hand, in the stationary reading mode, the document is placed downward on the transparent glass plate 14, and the first carriage 13A and the second carriage 13B are moved in the sub-scanning direction, that is, in the direction of the arrow D. Move along the bottom surface. At this time, the second carriage 13B moves at a speed that is half the moving speed of the first carriage 13A. As a result, the optical path length of the reflected light reflected from the original placed on the transparent glass plate 14 to the lens 135 is kept constant, and the image on the original is correctly formed on the reading sensor 136.

  Next, the second correction mode in this embodiment will be described.

  In the present embodiment, image tilt correction processing is performed in the second correction mode. In this image inclination correction process, the amount of inclination of the image represented by the image signal is calculated based on the image signal obtained by reading the document, and the image whose inclination is corrected based on the calculated amount of inclination is obtained. This is a process for generating a new image signal to be represented.

  In addition to the image recorded on the document, the image signal obtained by reading the document with the image reading device 10 includes a boundary line between the document itself and the background (reflecting member 137) that is out of the document, that is, the edge of the document. Contains information. Here, first, the leading edge of the document in the conveyance direction is detected based on the information on the edge of the document included in the input image signal. When the edge of the leading edge of the original is detected, the amount of inclination of the original is calculated next. Further, when the inclination amount of the original is calculated, the inclination of the image represented by the image signal is corrected next, and a new image signal representing the image whose inclination is corrected is generated.

  FIG. 5 is an explanatory diagram of the processing content of the image tilt correction processing.

  Here, first, the straight line representing the edge of the leading edge of the document and the inclination angle of the straight line are calculated by the Hough transform. Next, by the rotation process included in the affine transformation, the image on the document is rotated by an amount corresponding to the amount of inclination on the image signal, and a new image signal representing an image without inclination is generated.

  The Hough transform and the affine transform are widely known calculation methods, and only an outline thereof will be described here.

  6A to 6C of FIG. 6 are explanatory diagrams of the Hough transform.

  As described above, the document is transported on the transport path passing through the reading position, and an image on the document is read while passing through the reading position to generate an image signal. This image signal includes information on the edge of the document itself.

  In FIG. 6A, the horizontal axis x represents the position in the document width direction, and the vertical axis y represents the document conveyance direction.

  A straight line L shown in FIG. 6A is a straight line representing the edge of the leading edge of the document obtained as an image signal. However, this straight line is still unknown at this point, and here, it is assumed that points a to f which are supposed to be on the edge of the leading edge of the document are extracted from the obtained image signal. Among these points a to f, there are a large number of points on the straight line L (here, points a to e) representing the edge of the leading edge of the document, but they are represented by error points (here, point f). ) Is also present.

The straight line is defined by the length of the perpendicular line drawn from the origin O to the straight line as r and the inclination as θ.
r = x cos θ + ysin θ (1)
As shown in FIG. 9 (A),
r = r0, θ = θ0 (2)
Is determined, the straight line L shown in FIG. 6A is uniquely determined.

  The Hough transform is a calculation method for obtaining (r, θ) = (r0, θ0).

  FIG. 6B shows only a single point b in FIG. 9A and shows various straight lines passing through the point b (represented here by five straight lines L1 to L5). It is.

  Each perpendicular line from the origin O to each straight line L1 to L5 is dropped, the length of the perpendicular line is ri, and the angle is θi (i = 1,..., 5). FIG. 6B shows the lengths r3 and r4 and the angles θ3 and θ4 for the two straight lines L3 and L4.

  FIG. 6C is a diagram showing a Hough space composed of a perpendicular length r (horizontal axis) and an angle θ (vertical axis).

  When plotting the length r and the angle θ of the perpendicular lines for a large number of straight lines passing through the point b shown in FIG. 6B, a sinusoidal curve shown by the graph b in FIG. 9C is obtained. The curve of the graph b represents a group of straight lines passing through the point b.

  When not only the point b shown in FIG. 6A but also all the points a to f, a graph composed of the length r of the perpendicular and the angle θ is obtained in the same manner, the graph a to FIG. 6C shown in FIG. f.

  Here, the points (here, points a to e) that are correctly on the edge of the leading edge of the document pass through a certain point (r0, θ0) on the Hough space shown in FIG. A graph f representing a group of straight lines passing through the error point (here, point f) is a curve that does not pass through the point (r0, θ0).

  In this way, a large number of points on the edge of the document on the edge of the document are extracted, and a large number of graphs such as those shown in FIG. 6C are calculated. By finding it, it is possible to obtain (r0, θ0) that identifies the straight line L shown in FIG.

  Here, the straight line L representing the edge of the leading edge of the document is recognized by the Hough transform based on the image signal.

  FIG. 6D also shows a straight line L representing the edge of the leading edge of the document.

  At this stage, the straight line L has already been uniquely determined by the Hough transform described with reference to FIGS. That is, the angle θ0 is fixed.

Here, using this angle θ0,
τ0 = 90 ° −θ0 (3)
The inclination angle τ0 of the straight line L, that is, the inclination amount of the original is calculated by

  Further, the straight line L is rotated to calculate a straight line L ′ having no inclination.

That is, when the coordinates of a point on the straight line L (represented by the point b here) are (x, y), the new coordinates (x ′, y ′) obtained by rotating the point b by the angle τ0 are:
x ′ = x cos τ0−ysin τ0
y ′ = xsinτ0 + ycosτ0 (4)
It becomes.

  Here, the coordinates of all the pixels constituting the image represented by the image signal are converted according to the above equation (4). By doing this, the image signal representing the tilted image obtained by reading the document while the document is tilted is converted into a new image signal representing the image when the document is read without tilting. Is done.

  In the present embodiment, the image inclination correction process described above and the document inclination correction process described with reference to FIG. 5 are alternatively executed according to the operation mode.

  FIG. 6 is a perspective view showing an upper portion of the image forming apparatus.

  As described with reference to FIG. 3, the image reading apparatus 10 includes a document tray 11 and a document discharge tray 12. The document placed on the document tray 11 is carried in from the document carry-in entrance 118, and the image on the document is read and discharged onto the document discharge tray 12 as described above.

  Further, the document tray 11 is provided with a pair of guide members 117. The pair of guide members 117 are movable in opposite directions in the width direction, and draws the document placed on the document tray 11 from the both sides in the width direction to the center in the width direction. In conveying the original, the original is supported from both sides to guide the conveyance of the original. The pair of guide members 117 will be described in detail later.

  An opening / closing cover 119 that is opened when a document is jammed is provided above the document carry-in entrance 118. The opening / closing cover 119 is provided with a handle 119a. The opening / closing cover can be opened by placing a finger on the handle 119a and pulling it up.

  Further, the image reading apparatus 10 is provided with a guide wall 130 erected along the inner side edge of the document tray 11. A recess 131 is formed in the guide wall 130. When the pair of guide members 117 is opened to the maximum in the width direction, the first guide member 117a on the back side of the pair of guide members 117 enters the recess. The first guide member 117a and the second guide member 117b on the front side slide together so that when one of them is slid by hand, the other is positioned at an equal distance from the center in the width direction of the document tray 11. And has the effect of bringing the document to the center in the width direction. Here, this is referred to as a “center guide”. However, if the first guide member 117a on the back side is slid until it enters the recess 131 of the guide wall 130, the second guide member on the near side remains in the state where the first guide member 117a is inserted into the recess. Only 117b can be slid. At this time, the document on the document tray 11 is sandwiched between the back guide wall 130 and the second guide member 117b on the near side, and is brought close to the back side of the document tray 11. Here, this is referred to as a “corner guide”.

  FIG. 7 is a view showing the inside of the image reading apparatus when the opening / closing cover is opened.

  A first roll 111 and a first sensor 121 are provided immediately behind the document entrance 118 (see also FIG. 4). The first roll 111 is a roll that first feeds documents placed on the document tray 11 one by one. The first sensor 121 is a sensor that is pushed by the leading edge of the original fed by the first roll 111 and falls down, and detects the fall. The first sensor 121 detects that a document has been sent by the first roll 111.

  A second roll 112 is provided on the back side of the first roll 111 and the first sensor 121, and a second sensor 122 is provided on the back side. As described with reference to FIG. 4, the second roll 112 has a role of correcting the inclination of the original fed by the first roll 111 and feeding the original further. Similarly to the first sensor 121, the second sensor 122 is pushed by the leading edge of the document and falls down, and a plurality of second sensors 122 are arranged in the width direction of the document. These second sensors 122 detect that the document has been conveyed through the second roll 112, and depending on which second sensor of the plurality of second sensors 122 detects the original, This is a sensor that detects which width of the original has been conveyed.

  FIG. 8 is a diagram illustrating a first example of a switching structure that realizes switching between a center guide and a corner guide.

The first slide arm 701a from the first guide member 117a on the back side (left side in FIG. 8) of the pair of guide members 117 toward the second guide member 117b on the near side (right side in FIG. 8). Is extended. The first slide arm 701a is provided with a first rack gear 702a. The first slide arm 701a is a member that assists the sliding of the first guide member 117a, and slides integrally with the first guide member 117a.
Similarly, the second slide arm 701b extends from the second guide member 117b toward the first guide member 117a. This second slide arm 701b is also provided with a second rack gear 702b. The second slide arm 701b is a member for guiding the slide of the second guide member 117b, is fixed to the second guide member 117b, and slides integrally with the second guide member 117b. A pinion gear 710 is provided between the first slide arm 701a and the second slide arm 701b. The pinion gear 710 has a structure in which both the first rack gear 702a and the second rack gear 702b provided on each of the first slide arm 701a and the second slide arm 701b are engaged with each other. However, the first rack gear 702a is shorter than the second rack gear 702b, and the interval between the first guide member 117a and the second guide member 117b is set so that the first guide member 117a is in the recess 131 of the guide wall 130. When it is widened to the maximum, the first rack gear 702a is disengaged from the pinion gear 710 while the second rack gear 702b is kept engaged with the pinion gear 710, as shown in FIG. When the first rack gear 702a is disengaged from the pinion gear 710, that is, when the first guide member 117a enters the recess 131 of the guide wall 130, only the second guide member 117b can be slid. In a state in which the first guide member 117a is inserted into the recess 131 of the guide wall 130, the second guide member 117b is expanded so as to be located at the maximum front side (right side in FIG. 8), and then the first guide When the member 117a is slid so as to be pushed out from the recess 131, the first rack gear 701a is engaged with the pinion gear 730, and the first guide member 117a and the second guide member 117b move in a direction in which they are brought into contact with and separated from each other.

  Here, the first limit sensor 703a for detecting that the first guide member 117a is in the recess 131 of the guide wall 130 and the second guide member 117b are located on the side as far as possible. A limit sensor 703b for detecting this is provided. The first limit sensor 703a is in an ON state indicating that the first guide member 117a has entered the recess 131, and the second limit sensor 703b is in a position where the second guide member 117b is at the most front side. If the image reading apparatus 10 is in the off state indicating that there is not, the image reading apparatus 10 recognizes that it is in the “corner guide” state described above. On the other hand, when both the first guide member 117a and the second limit sensor 703b are in the off state, it is recognized that the state is the above-described “center guide”.

  Even when the second guide member 117b is not at the position where the second guide member 117b has moved to the maximum front side (the second limit switch 703b is in an on state), when the first guide member 117a is pushed out of the recess 131, The rack gear 702a on the first guide member 117a side meshes with the pinion gear 710. When this state occurs, the document is restricted to a halfway position that is neither a “corner guide” nor a “center guide”. In the first example shown in FIG. 8, in order to prevent this, when the second limit switch 703b is in an off state, a warning is issued if the first limit switch 703a changes to off, and the second limit switch 703b is turned off. The user is prompted to start over from the state where 703b is on (the second guide member 117b is fully opened).

  FIG. 9 is a diagram illustrating a second example of a switching structure that realizes switching between a center guide and a corner guide.

  In the second example, the first guide member 117a is detachable from the first slide arm 701a. FIGS. 9A to 9D are schematic diagrams sequentially illustrating the operation of the attachment / detachment mechanism from the attached state (FIG. 9A) to the removed state (FIG. 9D).

  The first slide arm 701a is provided with a fixing portion 705a for fixing the first guide member 117a. The fixing portion 705a has a fixing hole 704a into which the insertion portion 127a of the first guide member 701a is inserted. As shown in FIG. 9A, when the insertion portion 127a of the first guide member 117a is inserted into the fixing hole 704a, the first guide member 117a is fixed to the first slide arm 701a. The first guide member 117a is provided with a flange portion 137a. The flange portion 137a is hooked on the engagement protrusion 706a provided on the first slide arm 701a in the fixed state shown in FIG. 9A, and this prevents the first guide member 117a from coming off. Yes.

  Further, a protruding portion 132 protruding toward the collar portion 137a is formed on a portion of the guide wall 130 (see FIGS. 6 and 7) that forms a part of the housing of the image reading device and extends below the document tray 11. Is provided.

  Here, in a state where the first guide member 117a is fixed to the first slide arm 701a as shown in FIG. 9A, the first guide member 117a is placed on the guide wall 130 side (see also FIG. 6). Slide in the direction of arrow y toward. Then, as shown in FIG. 9B, the collar portion 137a hits the projection portion 132, and further, as shown in FIG. 9C, the collar portion 137a is pushed by the projection portion 132 and bent to engage the collar portion 137a. It will come off the mating protrusion 706a. In this state, when the first guide member 117a is lifted upward, the first guide member 117a is removed from the first slide arm 701a as shown in FIG. 9D.

  In order to mount the first guide member 117a on the first slide arm 701a, the first slide arm 701a is moved to a position where there is no interference with the protrusion 132 of the guide wall 130, and FIG. ), The first guide member 117a is lowered. Then, the insertion portion 127a of the first guide b member 117a enters the fixing hole 704a of the first slide arm 701a, and the flange portion 137a gets over the engagement projection 706a while interfering with the engagement projection 706a and bending. It is mounted in the state shown in FIG.

  As in the second example, the “center guide” and the “corner guide” can also be switched by providing a mechanism for attaching and detaching the first guide member 117a.

  The first guide member 117a is attached to and detached from the first slide arm 701a, that is, switching between the “center guide” and the “corner guide” is performed by a switch (not shown) that detects the attachment and detachment of the image reading apparatus 10. To be told.

  Here, a difference in advantages between the “center guide” and the “corner guide” will be described.

  In the “center guide”, a document placed on the document tray 11 is placed at a position close to the center in the width direction of the document tray 11 by a pair of guide members 117 (see FIGS. 3 and 6). It is conveyed and read while being guided by 117. The guide member 117 is shorter in the conveyance direction than the guide wall 130 (see FIG. 6) and is movable in the width direction. It is easy to tilt. If the sheet is conveyed while being inclined, there is a risk that it will protrude from the document reading width by the reading sensor 136 (see FIG. 4). In that case, a part of the image is not read and a part of the image is missing. On the other hand, in the case of the “side guide”, the posture of the document is easily stabilized, and there is little possibility that the document is conveyed while being inclined obliquely. However, in the case of the “side guide”, one side edge of the document keeps sliding with the member not only between the guide wall 130 but also during conveyance, and the document is stressed and a lot of paper dust is generated. Paper dust tends to accumulate inside the apparatus, and image defects due to paper dust are likely to occur due to influence on reading.

  Therefore, in the present embodiment, the “center guide” is basically used for a document of a normal size. In the case of a long document, if the inclination is small, the leading edge and the trailing edge are greatly shifted to the side even if the inclination is small. The “center guide” and “corner guide” in the present embodiment correspond to examples of the “first transport mode” and the “second transport mode” according to the present invention, respectively.

  Next, an image reading operation in this embodiment will be described.

  FIG. 10 is a diagram showing a correction switching setting screen. The correction switching setting screen 80 is a screen displayed on the touch panel 613 (see FIG. 3) during an initial setting operation by the user.

  On the correction switching setting screen 80, “Auto”, “Original correction”, and “Image correction” push buttons are arranged. In addition, a “set” button and a “cancel” button are also displayed. Here, “auto” will be deferred, and “original correction” and “image correction” will be described first. “Original correction” is a push button that is set in the first correction mode described with reference to FIG. 4 to correct the inclination of the conveyed document. “Image correction” is a push button that is set in the second correction mode described with reference to FIG. 5 and that corrects the inclination of the image based on the image signal obtained in reading the original. “Auto” is a push button for setting to automatically switch between the first correction mode and the second correction mode in accordance with conditions described later.

  When a push button of “Auto”, “Document correction” or “Image correction” is pressed on the correction switching setting screen 80 shown in FIG. 10 and the “Setting” button is further pressed, the push button is selected. Then, any one of “Auto”, “Original correction”, and “Image correction” is set, and the correction switching setting screen 80 disappears from the touch panel 613. When the “Cancel” button is pressed, the correction switching setting screen 80 disappears from the touch panel 613 without performing new settings. However, “setting” here means “storage” in a storage unit (not shown) provided in the circuit unit 70 shown in FIG. Preparation for actual operation based on the stored contents is performed separately. Details will be described later.

  Here, the setting on the correction switching setting screen 80 shown in FIG. 10 is an initial setting, and once set, it is valid until the next setting is repeated no matter how many times the job is repeated.

  FIG. 11 is a diagram showing a long document setting button.

  In the present embodiment, when a document having a length in the transport direction of a predetermined length (440 mm as an example) is placed on the document tray 11 and the document is to be read, the long mode setting is performed. Done. This long mode setting is performed by pressing a long document setting button 91 shown on the touch panel 613 shown in FIG. Unlike the correction switching setting shown in FIG. 10, the setting of the long mode is performed prior to the reading for each job of reading. When the reading of the original of the job is completed, the setting of the long mode is canceled, and the mode returns to the mode of reading a normal size original shorter than the long original.

  Here, it has been described that the setting of the long mode is to press the long document setting button 91 shown in FIG. 11 displayed on the touch panel 613, but the setting button 612 on the user interface 61 shown in FIG. One of them may be provided with a long document setting button. Alternatively, a sensor for detecting that a long document is placed on the document tray 11 may be provided, and the setting work by the user may be saved.

  FIG. 12 is a flowchart showing a first example of an operation sequence of the image reading apparatus constituting the multi-function peripheral of this embodiment when the start button shown in FIG. 3 is pressed.

  Here, one or a plurality of documents are first placed on the document tray 11. When the placed document is a long document, a long document setting button 91 shown in FIG. 11 is pressed. Thereafter, when the start button 611 shown in FIG. 3 is pressed, an operation according to the operation sequence shown in FIG. 12 is executed.

  Here, as an initial setting, any one of “Auto”, “Document correction”, and “Image correction” has already been set on the correction switching screen 80 shown in FIG.

  When execution of the operation according to the operation sequence shown in FIG. 12 is started, it is first determined whether or not the current job is a long document (see FIG. 11) (step S11).

  If it is determined that the document is not a long document, the process proceeds to step S12 to determine whether correction switching (see FIG. 10) is set to “auto”, “document correction”, or “image correction” (step S12). S12). Here, “setting” on the correction switching setting screen 80 means that the setting by the user operation is stored therein as described above. When “original correction” is set (stored), the “original correction” operation is set in accordance with the first correction mode for correcting the inclination of the original described with reference to FIG. 4 (step S13). On the other hand, when it is determined in step S12 that “image correction” is set, the second correction for correcting the inclination of the image based on the read image signal described with reference to FIG. The “image correction” operation according to the mode is set (step S14). If it is determined in step S12 that it is “auto”, since it is not a long document here (step S11), “image correction” is set. Note that the setting of “original correction” in step S13 or the setting of “image correction” in step S14 means specific preparation for an actual correction operation.

  When “original correction” is set in step S13 or “image correction” is set in step S03, the process proceeds to step S15, and whether or not the guide member 117a (see FIGS. 3 and 6) is in the “center guide” state. Is determined (step S15). If it is not “center guide”, a message is issued on the touch panel 613 (see FIG. 3) to change to “center guide” (step S16), and this operation sequence is terminated.

  In the present embodiment, when the document is not a long document, “center guide” is selected in both of “document correction” and “image correction”.

  If it is determined in step S15 that the state is the “center guide” state, the process proceeds to step S17, and the set “original correction” or “image correction” is executed until the end of the current job (step S18). However, the conveyance and reading of the document are repeated one by one.

  If it is determined in step S11 that the current job is a long document, the process proceeds to step S21. Here, the correction switching (see FIG. 10) is any of “auto”, “document correction”, and “image correction”. It is determined whether it is set to. When “original correction” is set (stored), the operation of “original correction” according to the first correction mode for correcting the inclination of the original described with reference to FIG. S22). On the other hand, when it is determined in step S21 that “image correction” is set (stored), “image correction according to the second correction mode for correcting the inclination of the image based on the image signal described with reference to FIG. The “correction” operation is set. Here, since the document is a long document, in the case of “auto”, the process proceeds to “document correction” (step S22). Here, the setting of “original correction” in step S22 or the setting of “image correction” in step S23 refers to specific preparation for the actual correction operation as in steps SS13 and S14.

  When “original correction” is set in step S22 or “image correction” is set in step S23, the process proceeds to step S24, and whether or not the guide member 117 (see FIGS. 3 and 6) is in the “corner guide” state. Is determined (step S24). In this embodiment, for a long document, “corner guide” is selected for both “document correction” and “image correction”. When not in the “corner guide” state, a message is issued on the touch panel 613 (see FIG. 3) to change to “corner guide” (step S25), and this operation sequence is terminated. If it is determined in step S24 that the state is the “corner guide” state, the process proceeds to step S17, and the set “original correction” or “image correction” is executed until the end of the current job (step S18). However, the conveyance and reading of the document are repeated one by one.

  FIG. 13 is a flowchart showing a second example of the operation sequence of the image reading apparatus when the start button shown in FIG. 3 is pressed. Here, differences from the first example shown in FIG. 12 will be described.

  Here, the correction switching setting (see FIG. 10) is performed as an initial setting, and whether or not the current job is a long document (see FIG. 11) is set. Thereafter, when the start button 611 is pressed, the operation sequence shown in FIG. 13 is executed instead of the operation sequence shown in FIG.

  The operation sequence of the second example shown in FIG. 13 is different from the operation sequence of the first example shown in FIG. 12 only in the following one point. That is, in the case of the operation sequence of the first example shown in FIG. 12, in the case of a long document (step S11), even when “document correction” is set (step S22), “image correction” is set. As in the case of being done, it is required to be a corner guide (step S24). On the other hand, in the operation sequence of the second example shown in FIG. 13, even if the document is a long document (step S11), if “document correction” is set (step S22), it is “corner guide”. Regardless of whether it is a “center guide” or not, the document is conveyed and read (steps S17 and S18). In other words, in this second example, since the posture of the original is corrected by “original correction” even for a long original, the original is conveyed and read even for the “center guide”.

  Here, the operation sequence of the image reading apparatus 10 has been described, but this operation sequence does not ask the destination of the image signal obtained by reading by the image reading apparatus 10, and sends the image signal to the image forming apparatus 20. You may use for formation of a copy image. Alternatively, the image signal may be transmitted by facsimile via the FAX interface 50 (see FIG. 1) or transmitted to a personal computer or the like via the I / O interface 40.

  Although an example of the image reading apparatus of the present invention and a multifunction peripheral including an example of the copying machine of the present invention have been described here, the present invention can also be applied to a single-function image reading apparatus or copying machine.

DESCRIPTION OF SYMBOLS 1 Multifunction device 10 Image reading device 11 Document tray 12 Document discharge tray 20 Image forming device 30 Signal processing unit 40 I / O interface 50 FAX interface 60 Control unit 61 User interface 70 Circuit unit 80 Correction switching setting screen 91 Long document setting button 117, 117a, 117b Guide member 118 Document entrance 119 Open / close cover 136 Reading sensor 611 Start button 612 Setting button 613 Touch panel 701a, 702b Slide arm 702a, 702b Rack gear 710 Pinion gear

An object of the present invention is to provide an image reading apparatus and a copying machine in which correction processing is performed in accordance with whether a document is long .

Claim 1
A document placement section on which a document is placed;
A document conveying section that conveys the document and passes the reading position;
A document reading unit that reads an image of the document at the reading position;
When the document is a long document whose length in the transport direction exceeds a predetermined length, a first correction process for performing a tilt correction process of the transported document is performed,
When the original is not a long original, the image reading apparatus performs a second correction process for correcting the inclination of the read image .

Claim 2
A reception unit for accepting that the document is a long document,
2. The image reading apparatus according to claim 1 , wherein when the document is a long document, the document is a long document .

Claim 3
The document placing unit further includes a detection unit for detecting that a long document is placed,
When it is detected that the long document is placed, an image reading apparatus according to claim 1, characterized in that said document with long documents.

Claim 4
4. The apparatus according to claim 1, wherein the first correction process corrects an inclination of the document on an upstream side of the reading position of the document transport by the document transport unit. 5. It is an image reading apparatus of description.

Claim 5
The second correction processing, any of the claims 1-3, characterized in that the inclination on the basis of the image signal generated by said original reading unit generates a new image signal representing the corrected image The image reading apparatus according to claim 1.

Claim 6
An image reading apparatus according to any one of claims 1 to 5,
An image forming apparatus that forms an image on a sheet based on an image signal generated by the image reading apparatus .

According to the image reading apparatus of the first aspect and the copying machine of the sixth aspect, the correction process is performed according to whether or not the document is long .

According to the image reading apparatus of the second aspect, the user can specify that correction processing suitable for a long document is performed .

According to the image reading apparatus of the third aspect, forgetting to set the long document is prevented .

According to the image reading apparatus of the fourth aspect, it is possible to reduce the inclination of the document before the reading of the long document at the reading position is started .

According to the image reading apparatus of the fifth aspect, the generation of sound can be reduced as compared with the case where the present configuration is not adopted.

Claims (4)

A document placement section on which a document is placed;
A document conveying section that conveys the document and passes the reading position;
A document reading unit that reads an image of the document at the reading position;
When the original is a long original whose length in the conveyance direction exceeds a predetermined length, a first process for performing an inclination correction process of the conveyed original is performed,
An image reading apparatus that performs a second process of correcting the inclination of the read image when the original is not a long original. A reception unit for accepting that the manuscript is long,
2. The image reading apparatus according to claim 1, wherein when the document is a long document, the document is a long document. The document placing unit further includes a detection unit for detecting that a long document is placed,
2. The image reading apparatus according to claim 1, wherein when it is detected that a long document is placed, the document is a long document. An image reading apparatus according to any one of claims 1 to 3,
An image forming apparatus for forming an image on a sheet based on an image signal generated by the image reading apparatus.

Images