Image processing apparatus

An image processing apparatus includes a document table, an image reading portion, a cover portion, a presser sheet, and a sheet winding portion. The presser sheet is provided on the cover portion, and contacts the document on the document table when the cover portion is positioned at the closing position. The sheet winding portion allows a first portion of the presser sheet to extend along the document table while holding a second portion of the presser sheet in a wound state. The sheet winding portion can feed the second portion when an external force is applied to the first portion. In the cover portion, a retreat space is formed so that the first portion of the presser sheet and a portion of the second portion fed from the sheet winding portion can retreat into the retreat space.

INCORPORATION BY REFERENCE

This application is based upon and claims the benefit of priority from the corresponding Japanese Patent Application No. 2016-065674 filed on Mar. 29, 2016, the entire contents of which are incorporated herein by reference.

BACKGROUND

The present disclosure relates to an image processing apparatus.

In general, an image processing apparatus such as a scanner or a copier having a function to read an image from a document, includes a document table (platen glass) on which the document is placed, and a cover portion that covers the document table. The cover portion is pivotably supported so as to pivot between a closing position to cover the document table and an opening position to open a space on the document table.

In addition, a document conveying portion called ADF (Auto Document Feeder) is often provided in the cover portion. The document conveying portion conveys sheets of documents one by one from a supply tray formed on the cover portion to a discharge tray via a document conveyance path. In this case, an image reading portion can read an image from a document in a placement mode and a conveyance mode.

In the placement mode, an image is read from a document placed on the document table, and in the conveyance mode, an image is read from a document while the document is conveyed along the document conveyance path.

There is known an image processing apparatus including slide rails that can lift up and down a hinge portion of the cover portion. With this configuration, when a book document with a large thickness is placed on the document table, the cover portion, while extending horizontally, can hold the book document.

SUMMARY

An image processing apparatus according to an aspect of the present disclosure includes a document table, an image reading portion, a cover portion, a presser sheet, and a sheet winding portion. On the document table, a document is placed. The image reading portion reads an image from the document placed on the document table. The cover portion is supported in such a way as to pivot between a closing position to cover the document table and an opening position to open a space on the document table. The presser sheet has a belt-like shape, is provided on the cover portion, and contacts the document on the document table when the cover portion is positioned at the closing position. The sheet winding portion is provided on the cover portion, allowing a first portion to extend along the document table while holding a second portion in a wound state, and can feed the second portion when an external force is applied to the first portion, the first portion being a part of the presser sheet, the second portion being another part of the presser sheet including an end of the presser sheet. In the cover portion, a retreat space is formed so that the first portion of the presser sheet and a portion of the second portion fed from the sheet winding portion can retreat into the retreat space.

An image processing apparatus according to another aspect of the present disclosure includes the document table, the image reading portion, the cover portion, and a document pressing portion. The document pressing portion is provided on the cover portion and includes at least one panel portion that presses the document on the document table. The panel portion is supported by the cover portion to be at a reference position along the document table so that the panel portion can be displaced into a retreat space formed in the cover portion from the reference position when an external force is applied from the document table side.

DETAILED DESCRIPTION

The following describes embodiments of the present disclosure with reference to the accompanying drawings. It should be noted that the following embodiments are examples of specific embodiments of the present disclosure and should not limit the technical scope of the present disclosure.

As shown inFIG. 1andFIG. 2, an image processing apparatus10according to the first embodiment includes an image reading device1, an image forming device2, a control portion8, and an operation/display portion80. For example, the image processing apparatus10is a copier, a facsimile, or a multifunction peripheral.

The image reading device1includes an image reading portion11, a transparent platen glass15, a transparent contact glass14, and a platen cover12. An ADF (Auto Document Feeder)13is embedded in the platen cover12.

The image processing apparatus10performs image processing of an image of a document9placed on the platen glass15. The platen glass15is a document table on which the document9is placed, and is an upper surface of a main body portion100of the image reading portion11.

The image processing includes an image reading process to read an image from the document9, and further includes a process for processing or transporting data of the image read from the document9, and a process for forming the image read from the document9, onto a sheet90.

As shown inFIG. 2, the platen cover12is pivotably supported by a hinge124provided on the main body portion100of the image reading device1. The platen cover12can pivot between a closing position to cover the platen glass15from above, and an opening position to open a space on the platen glass15. It is noted that the platen cover12is an example of the cover portion.

The platen cover12includes a supply tray121, a document conveyance path122, and a discharge tray123. The ADF13conveys each document9from the supply tray121to the discharge tray123via the document conveyance path122.

The ADF13includes a feed roller131, a conveyance roller132, and a discharge roller133, wherein the feed roller131feeds the document9from the supply tray121, the conveyance roller132conveys the document9along the document conveyance path122, and the discharge roller133discharges the document9from an outlet122aof the document conveyance path122onto the discharge tray123. It is noted that the ADF13is an example of the document conveying portion.

The image reading portion11includes a plurality of mirrors113, a moving unit111, a movement mechanism110, and an image sensor115, wherein the moving unit111includes a light source112and a part of the plurality of mirrors113.

The movement mechanism110causes the moving unit111to move along a sub scanning direction D2perpendicular to a main scanning direction D1. The movement mechanism110causes the moving unit111to move along the platen glass15.

Alternatively, the movement mechanism110can position the moving unit111at a position facing a reading position P0on the contact glass14that is disposed on the extension line of the platen glass15. The reading position P0is included in the document conveyance path122.

The light source112emits light from below the platen glass15to irradiate a line region extending on the platen glass15or the contact glass14along the main scanning direction D1. InFIG. 1, the main scanning direction D1is a direction perpendicular to the plane of the figure.

Light is emitted from the light source112to the platen glass15or the contact glass14, and reflection light from the document9placed on the platen glass15is guided by the mirrors113and a lens114to a light receiving portion of the image sensor115.

The image sensor115is a sensor for detecting, for each pixel, a light amount of the reflection light reflected from the document9. The image sensor115outputs the data of the detected light amount for each pixel, as image data D0.

The image sensor115shown inFIG. 1is a CCD (Charge Coupled Device). It is noted that a contact image sensor (CIS) in which the light source112, the lens114and the image sensor115are integrally formed, may be adopted. In this case, the moving unit111includes the CIS.

The image reading portion11can read a document image in a placement mode and in a conveyance mode, wherein in the placement mode, an image is read from a document9placed on the platen glass15, and in the conveyance mode, an image is read from a document9conveyed along the document conveyance path122. It is noted that the document image is an image formed on the document9.

During the image reading process in the placement mode, the image reading portion11scans a light beam along the platen glass15, receives reflection light, and outputs the image data D0that corresponds to the light amount of the reflection light. The image data D0is data of the document image.

In addition, during the image reading process in the conveyance mode, the ADF13conveys a document9, and the image reading portion11irradiates light on the document9while the document9passes the reading position P0, receives reflection light, and outputs the image data D0that corresponds to the light amount of the reflection light. With the image reading process, the image reading portion11reads the document image.

Furthermore, the image reading device1of the image processing apparatus10includes a cover sensor801and a document sensor802.

The cover sensor801detects whether or not the platen cover12is present at the closing position (seeFIG. 2). The document sensor802detects whether or not a document9is present on the supply tray121. For example, each of the cover sensor801and the document sensor802may be a contact-type limit switch or a noncontact-type proximity switch.

The image forming device2can perform a copy process in which to form an image corresponding to the image data D0obtained in the image reading process, on a sheet90supplied from a sheet supply portion3. In addition, the image forming device2can execute a print job that is received from an external apparatus via a communication portion (not shown). The sheet90is a sheet-like image formation medium such as a sheet of paper or an envelope.

The image forming device2shown inFIG. 1forms a toner image on the sheet90by the electrophotographic system. It is noted that the image forming device2may form an image on the sheet90by another system such as the inkjet system.

The operation/display portion80is a user interface device including: an operation portion that receives an operation for input of information; and a display portion that display information. The control portion8controls the operation/display portion80and other electric devices included in the image processing apparatus10.

In the following description, a relatively thick document9such as a book or a pamphlet having a lot of pages, is referred to as a book document9a(seeFIG. 4,FIG. 5,FIG. 10).

Meanwhile, in a case where a thick document9such as the book document9ais placed on the platen glass15, in conventional image processing apparatuses, the platen cover12cannot be closed up to a position proximate to the platen glass15. In the state where the platen cover12is away from the platen glass15, the document conveyance path122of the platen cover12is away from the reading position P0of the contact glass14. In this case, the image reading portion11cannot execute the image reading process in the conveyance mode correctly.

As a result, in a case where the image reading process needs to be executed in the conveyance mode and the placement mode in series, the user has to do a troublesome work of performing individually an operation to execute the conveyance mode and an operation to execute the placement mode with an operation to remove the book document9afrom the platen glass15between the operations.

Furthermore, in a case where the copy process that includes the image reading process performed in the two modes in series, needs to be executed, it is necessary to do a more troublesome work of inserting sheets of copies obtained in the placement mode into sheets of copies obtained in the conveyance mode at target pages.

In addition, when a large gap is generated between the platen cover12and the platen glass15, strong external light enters the image reading portion11from the gap. This may cause a noise to be generated in the image data D0obtained by the image reading portion11due to the external light.

The image processing apparatus10has a configuration to prevent the platen cover12from lifting from the platen glass15when a thick document9such as the book document9ais placed on the platen glass15. The following describes the configuration.

As shown inFIG. 3toFIG. 5, the image reading device1of the image processing apparatus10includes a document pressing portion16that includes a presser sheet161and a sheet winding portion163that are both provided in the platen cover12.

The presser sheet161is a belt-like sheet configured to contact the document9placed on the platen glass15when the platen cover12is positioned at the closing position. A first end161a, which is one of opposite ends of the presser sheet161in its longitudinal direction, is supported at a constant position by a support portion162of the platen cover12.

The sheet winding portion163allows a first portion161c, which is a part of the presser sheet161, to extend along the platen glass15while holding a second portion161d, which is another part of the presser sheet161, in a wound state. The first portion161cis a portion of the presser sheet161on the first end161aside, and the second portion161dis an end portion of the presser sheet161including a second end161b. The second end161bis an end of the presser sheet161opposite to the first end161a.

The platen cover12rotatably supports a pair of tension rollers164at two positions along the platen glass15. The pair of tension rollers164position the first portion161cof the presser sheet161along the platen glass15by contacting opposite ends of the first portion161cof the presser sheet161in its longitudinal direction.

The sheet winding portion163includes, for example, a well-known winding mechanism of a spiral spring type that is adopted in the winding measure or the like. In the sheet winding portion163, the spiral spring applies an elastic force in a direction of winding the presser sheet161, to a core member that winds the presser sheet161.

The sheet winding portion163uses the elastic force of the spiral spring to allow the first portion161cof the presser sheet161to extend along the platen glass15while keeping the second portion161dof the presser sheet161to be wound by the core member that is not shown.

The sheet winding portion163is configured to feed the second portion161dof the presser sheet161when an external force is applied to the first portion161cof the presser sheet161. The external force applied to the first portion161cis a force in a direction of drawing out the second portion161dof the presser sheet161from the sheet winding portion163, namely, a force against the elastic force of the spiral spring.

In the platen cover12, a retreat space120is formed so that the first portion161cof the presser sheet161and the second portion161dfed from the sheet winding portion163can retreat into the retreat space120.

When the platen cover12is closed in a state where the book document9ais placed on the platen glass15, the first portion161cof the presser sheet161contacts the book document9a, receives a force from the book document9a, and is pressed by the force that is greater than the elastic force in the direction of winding the spiral spring. This causes the sheet winding portion163to feed a part of the second portion161dof the presser sheet161, and the first portion161cand the fed part of the second portion161dare displaced to the retreat space120along the upper surface of the book document9a.

In addition, the book document9ais pressed against the platen glass15by the tensile force of the presser sheet161. It is noted that in a case where an extremely thin document9is placed on the platen glass15, the presser sheet161extends and presses the document9against the platen glass15while being in a flat state.

With the above-described configuration, at least one end portion of the presser sheet161is held by the sheet winding portion163. This makes it possible to close the platen cover12completely even when the book document9ais placed on the platen glass15. That is, the configuration makes it possible to prevent a lift of the platen cover12.

According to a conventional technique, when the image reading process is executed in the conveyance mode and the placement mode in series, the user has to do a troublesome work of executing individually the process of the conveyance mode and the process of the placement mode, and removing the book document9afrom the platen glass15before returning to the process of the conveyance mode. However, the above-described configuration eliminates the troublesome work of the user.

As shown inFIG. 3toFIG. 5, the discharge tray123is formed at a position to face the presser sheet161via the retreat space120. The discharge tray123is supported in such a way as to be displaced to a side opposite to the retreat space120when pressed by the presser sheet161that has retreated into the retreat space120.

In the present embodiment, the discharge tray123has a link mechanism wherein two document receiving portions123aare coupled with each other by a coupling shaft123d. One document receiving portion123aincludes a support shaft123cthat is rotatably supported by a bearing portion17aat an end opposite to the coupling shaft123d, and the document receiving portion123acan pivot around the support shaft123c.

The other document receiving portion123aincludes a movable shaft123ethat is slidably supported by a slide support portion17bat an end opposite to the coupling shaft123dso as to be slidable along a document discharge direction.

Furthermore, the discharge tray123includes movable side wall portions123bconnected to opposite side edges of each document receiving portion123a. In addition, fixed side wall portions17care formed at positions on the platen cover12that overlap the movable side wall portions123b. The movable side wall portions123bpivot in conjunction with the document receiving portions123a. On the other hand, the fixed side wall portions17cform walls that surround the retreat space120at constant positions on the platen cover12.

In the platen cover12, the entire peripheral of the retreat space120is surrounded by the presser sheet161, the discharge tray123, and partition wall portions including the fixed side wall portions17c.

When the presser sheet161is displaced upward over the retreat space120along the upper surface of the thick book document9a, the presser sheet161pushes the discharge tray123from the retreat space120side toward the opposite side, namely, from below to above.

Upon being pushed by the presser sheet161that has retreated into the retreat space120, the discharge tray123is displaced to a side opposite to the retreat space120. Specifically, the movable shaft123eslides to be displaced, and the two document receiving portions123aare displaced in a state of being bent at the coupling shaft123d(seeFIG. 5).

In the image processing apparatus10, a gap through which external light enters the image reading portion11, is not formed as far as the presser sheet161is displaced within the retreat space120. As a result, it is possible to prevent a noise due to the external light from being generated in the image data D0obtained by the image reading portion11.

In addition, even in a case where the presser sheet161is displaced to such an extent as to push up the discharge tray123, a gap through which external light enters, is minimized due to the action of the fixed side wall portions17cthat overlap the movable side wall portions123b.

Since the discharge tray123is displaced in a direction of expanding the retreat space120, even in a case where the thick book document9ais placed on the platen glass15, it is possible to prevent the platen cover12from lifting.

In addition, the image reading device1includes a feed sensor803configured to detect that the presser sheet161has been fed from the sheet winding portion163. Hereinafter, a state where the feed sensor803has detected that the presser sheet161was fed from the sheet winding portion163, is referred to as a feed detected state.

When the platen cover12is closed in a state where the book document9ais placed on the platen glass15, a part of the second portion161dof the presser sheet161is fed from the sheet winding portion163. Accordingly, it is also possible to say that the feed sensor803can detect whether or not the book document9ais placed on the platen glass15.

For example, the feed sensor803may be a photosensor that emits light to a reflection portion161estuck or applied to the presser sheet161, and detects the reflection light. It is noted that the feed sensor803is an example of the feed detecting portion.

It is noted that the feed sensor803may be, for example, a photosensor that emits light to a hole formed in the presser sheet161, and detects the reflection light. Use of the feed sensor803is described below.

As shown inFIG. 6, the control portion8includes a UI (User Interface) control portion81, a state determining portion82, a reading control portion83, an image processing portion84, a print control portion85, and a non-transitory computer-readable storage portion86.

For example, components of the control portion8other than the storage portion86may be composed of a processor such as a MPU (Micro Processor Unit) or a DSP (Digital Signal Processor), or a circuit such as an ASIC (Application Specific Integrated Circuit).

The storage portion86stores various types of data and programs that are referenced by the UI control portion81, the state determining portion82, the reading control portion83, the image processing portion84, and the print control portion85. The MPU and the DSP include a RAM (Random Access Memory) that can temporarily store programs that perform data processing and data as the target of the data processing.

The UI control portion81controls the operation/display portion80. The state determining portion82determines the state of the image reading device1based on the detection results of the cover sensor801, the document sensor802, and the feed sensor803.

For example, the UI control portion81executes an ordinal position specification process by controlling the operation/display portion80. The ordinal position specification process is executed to specify an ordinal position of the image reading process in the placement mode, in a case where the image reading process is executed in the conveyance mode and the placement mode in series.

In the ordinal position specification process, the UI control portion81sets an ordinal position of the image reading process in the placement mode, in accordance with a specification operation performed by the user on the operation/display portion80. In the following description, a numeral that is specified in the ordinal position specification process as the ordinal position of the image reading process in the placement mode, is referred to as a specification number. It is noted that the UI control portion81is an example of the ordinal position specifying portion.

The ordinal position specification process is executed in accordance with an operation of the user before the image reading process is executed in a state where documents9are placed on both the supply tray121and the platen glass15. When the specification number is specified, the image reading portion11executes the image reading process in an insertion mode.

The image reading process in the insertion mode includes the image reading process in the conveyance mode and the image reading process in the placement mode. More specifically, during the image reading process in the insertion mode, the image reading portion11executes in succession: a process of reading an image from a sheet of document in the conveyance mode at each ordinal position other than the ordinal position specified by the specification number; and a process of reading an image from a document in the placement mode at the ordinal position specified by the specification number.

For example, suppose that 3 (three) is specified as the specification number in a state where five sheets of documents9are placed on the supply tray121and the book document9ais placed on the platen glass15. In this case, the image reading portion11executes the image reading process in the conveyance mode with respect to the first and second sheets of document9on the supply tray121, and then executes the image reading process in the placement mode with respect to the book document9a, and then executes the image reading process in the conveyance mode with respect to the remaining sheets of documents9on the supply tray121. This is an example of the image reading process in the insertion mode.

The reading control portion83controls the image reading portion11, and the image processing portion84executes a process of calculating the image data D0obtained from the image sensor115, namely, executes the image processing. The print control portion85controls the image forming device2.

Next, an example of the procedures of a scan control executed by the control portion8is described with reference to the flowchart shown inFIG. 7. In the following description, S101, S102, . . . are identification signs representing the steps executed by the control portion8.

In the scan control, first the UI control portion81determines whether or not a predetermined reading start event has occurred, and waits until the reading start event occurs.

For example, the reading start event may be an operation of a start button80aprovided on the operation/display portion80(seeFIG. 2).

When the UI control portion81determines that the reading start event has occurred, the state determining portion82executes a cover closure determination, a conveyance document presence/absence determination, and an ordinal position specification determination, as the processes for determining the state of the image reading device1.

The cover closure determination is a process to determine whether or not the platen cover12is present at the closing position, based on the detection result of the cover sensor801. The conveyance document presence/absence determination is a process to determine whether or not the document9is present on the supply tray121, based on the detection result of the document sensor802. The ordinal position specification determination is a process to determine whether or not the specification number has been specified in advance in the ordinal position specification process.

Upon determining that the platen cover12is not present at the closing position, the state determining portion82moves the process to step S103. In addition, upon determining that the platen cover12is present at the closing position and the document9is not present on the supply tray121, the state determining portion82moves the process to step S104.

In addition, upon determining that the platen cover12is present at the closing position, that the document9is present on the supply tray121, and that the specification number has not been specified in advance, the state determining portion82moves the process to step S105.

In addition, upon determining that the platen cover12is present at the closing position, that the document9is present on the supply tray121, and that the specification number has been specified in advance, the state determining portion82moves the process to step S107.

In step S103, the UI control portion81determines whether or not a confirmation input operation has been performed on the operation/display portion80to permit the image reading process to be executed in the present state.

The UI control portion81then repeats the processes of steps S102and S103until it is determined that the platen cover12is present at the closing position, or it is determined that the confirmation input operation has been performed.

Upon determining that the platen cover12is not present at the closing position, and that the confirmation input operation has been performed, the UI control portion81moves the process to step S104.

In step S104, the image reading portion11executes the image reading process in the placement mode under the control of the reading control portion83. In addition, in a case where the copy mode has been selected in advance, the print control portion85, in step S104, causes the image forming device2to execute a print process to form, on a sheet90, an image represented by the image data D0obtained in the image reading process in the placement mode. After the execution of the process of step S104, the processes from step S101are repeated.

As described above, the process of step S104is executed when any of the following two types of detection results is obtained. One of the detection results is that the platen cover12is not present at the closing position and the confirmation input operation has been performed. The other detection result is that the platen cover12is present at the closing position and a document9is not present on the supply tray121.

In step S105, the status determining portion82determines whether or not the feed sensor803is in the feed detected state, namely, whether or not the book document9ais present on the platen glass15.

Upon determining that the feed sensor803is in the feed detected state, the status determining portion82moves the process to step S106, and otherwise, moves the process to step S108.

As described above, the process of step S105is executed when it is determined that the platen cover12is present at the closing position, that the document9is present on the supply tray121, and that the specification number has not been specified in advance.

In step S106, the UI control portion81executes the ordinal position specification process by controlling the operation/display portion80. For example, when the user has forgotten to specify the specification number in advance, the UI control portion81urges the user to specify the specification number. After step S106, the UI control portion81moves the process to step S107.

In step S107, the image reading portion11executes the image reading process in the insertion mode in accordance with a control performed by the reading control portion83. In addition, when the copy mode has been selected in advance, in step S107, the print control portion85causes the image forming device2to execute a print process to form, on a sheet90, an image represented by the image data D0obtained in the image reading process in the insertion mode.

With execution of the process of step S107in the copy mode, sheets of copies of the documents9placed on the supply tray121and the platen glass15are obtained, and sheets of copies of the document9placed on the platen glass15are automatically inserted at a position (page) specified by the specification number. After execution of the process of step S107, the processes from step S101are repeated.

It is noted that in the ordinal position specification process, the head page (position) or the last page (position) may be specified as the specification number.

As described above, the process of step S107is executed when the specification number has been specified in the ordinal position specification process before the reading start event occurs, or in the ordinal position specification process in step S106.

According to the image processing apparatus10, even when the book document9ais placed on the platen glass15, the platen cover12can pivot to the closing position. As a result, the user does not need to remove the book document9afrom the platen cover12during execution of the image reading process in the insertion mode. Accordingly, the user's operation becomes easy when the image reading process is executed in the conveyance mode and the placement mode in series.

In step S108, the image reading portion11executes the image reading process in the conveyance mode under the control of the reading control portion83. In addition, when the copy mode has been selected in advance, in step S108, the print control portion85causes the image forming device2to execute a print process to form, on a sheet90, an image represented by the image data D0obtained in the image reading process in the conveyance mode. After the process of step S108, the processes from step S101are repeated.

As described above, the process of step S108is executed when it is determined that the platen cover12is present at the closing position, that the specification number has not been specified in advance, and that the feed sensor803is not in the feed detected state.

In addition, the image processing portion84performs a book document processing control during the image reading process executed in step S104, and during the image reading process in the placement mode that is executed as a part of the image reading process in the insertion mode in step S107.

The book document processing control is performed to determine whether or not to execute, on the image data D0, a special book document processing for the book document9a, depending on whether or not the image data D0obtained from the document9on the platen glass15was obtained when the feed sensor803was in the feed detected state. A concrete example of the book document processing is described below.

In the following, an example of the procedures of the book document processing control executed by the image processing portion84is described with reference to the flowchart shown inFIG. 8. In the following description, S201, S202, . . . are identification signs representing the steps executed by the image processing portion84.

When the image reading portion11obtains the image data D0from the document9on the platen glass15, the image processing portion84executes predetermined common image processing on the image data D0.

The common image processing is image processing that is commonly executed on the image data D0regardless of the type of the document9.

Furthermore, the image processing portion84determines whether or not the image data D0obtained from the document9on the platen glass15was obtained when the feed sensor803is in the feed detected state. It is noted that the image data D0obtained from the document9on the platen glass15was obtained in the image reading process in the placement mode in step S104or S107.

Upon determining that the image data D0obtained from the document9on the platen glass15was obtained when the feed sensor803is in the feed detected state, the image processing portion84executes the book document processing in step S203, and otherwise, ends the book document processing control.

In step S203, the image processing portion84executes the book document processing on the image data D0obtained from the document9on the platen glass15. Thereafter, the image processing portion84ends the book document processing control.

In the book document processing, the image processing portion84executes a predetermined process on data of a central area in a coordinate axis direction (x-axis direction or y-axis direction) in the image data D0, the predetermined process being different from a process executed on data of the other areas.

The central area corresponds to a boundary portion between two pages of the center spread in the book document9a. For example, the image processing portion84determines whether the center spread of the book document9aextends in the x-axis direction or in the y-axis direction by comparing a candidate for the central area in the x-axis direction and a candidate for the central area in the y-axis direction with regard to a ratio of an area occupied by a shadow image to the entire area.

The shadow image is a gray image that is approximate to a black image in a predetermined range. In general, the central area in the image data D0obtained from the book document9ahas a high ratio of the shadow image.

For example, in the book document processing, the image processing portion84replaces the shadow image data in the central area with base image data that is detected from the other areas.

In addition, in the book document processing, when the central area includes character images, the image processing portion84may execute a distortion correcting process to correct a distortion of the character images.

In general, the character image in the central area of the image data D0obtained from the book document9ais distorted. Specifically, the closer to the boundary line, between two pages of the center spread, the character image is, the narrower the width of the character image is in a direction perpendicular to the boundary line. In the distortion correcting process, a portion of the character image close to the boundary line is stretched in the direction perpendicular to the boundary line.

As described above, the image processing portion84executes the book document processing in a case where the image data D0of the document9on the platen glass15has been obtained by the image reading portion11in a state where the feed sensor803detected that the presser sheet161had been fed from the sheet winding portion163.

In other words, the image processing portion84selects whether to execute the book document processing on the image data D0, depending on whether the image data D0read from the document9on the platen glass15was obtained when the feed sensor803was in the feed detected state.

With the book document processing control, the book document processing suitable for the book document9ais automatically executed based on the detection result of the feed sensor803.

Next, a description is given of an image processing apparatus10xaccording to the second embodiment with reference toFIG. 9andFIG. 10. InFIG. 9andFIG. 10, the same components as those shown inFIG. 1toFIG. 8are assigned the same reference signs. The following describes the difference of the image processing apparatus10xfrom the image processing apparatus10.

Compared to the image processing apparatus10shown inFIG. 1toFIG. 8, the image processing apparatus10xincludes, in place of the document pressing portion16and the discharge tray123, a document pressing portion18and a discharge tray123xthat have different structures from the document pressing portion16and the discharge tray123, respectively.

The document pressing portion18is, as is the case with the document pressing portion16, provided in the platen cover12. The document pressing portion18includes a plurality of panel portions181and182that press the document9on the platen glass15. In the present embodiment, the document pressing portion18includes one fixed panel portion181and two movable panel portions182.

The fixed panel portion181is supported by the platen cover12at a constant position along the platen glass15. The two movable panel portions182are supported by the platen cover12to be at a reference position along the platen glass15such that they are displaced from the reference position into the retreat space120formed in the platen cover12when an external force is applied from the platen glass15side.

FIG. 9shows a state where the two movable panel portions182are positioned at the reference position.FIG. 10shows a state where the two movable panel portions182have been displaced from the reference position into the retreat space120.

The fixed panel portion181and the two movable panel portions182positioned at the reference position are flush with each other along the platen glass15. At least a part of the fixed panel portion181is closer to the ADF13than to the discharge tray123x. On the other hand, the two movable panel portions182are disposed to face the discharge tray123x. The retreat space120is a space that is present between the two movable panel portions182and the discharge tray123x.

The two movable panel portions182includes, respectively, support shafts123cthat are rotatably supported by bearing portions17dat opposite ends respectively, and the two movable panel portions182can pivot around the support shafts123c, respectively.

As shown inFIG. 10, upon contacting the book document9aplaced on the platen glass15, the two movable panel portions182receive pressures from the book document9a, and are pivoted and displaced into the retreat space120.

In the image processing apparatus10x, the two movable panel portions182play the same role as the presser sheet161in the image processing apparatus10. As a result, as is the case with the image processing apparatus10, the image processing apparatus10xprevents the platen cover12from lifting when the book document9ais placed on the platen glass15.

In addition, in the present embodiment, the document pressing portion18includes a spring184which is an elastic member whose opposite ends are coupled with the two movable panel portions182, respectively. The spring184applies an elastic force that holds the two movable panel portions182at the reference position.

The two movable panel portions182press the document9against the platen glass15by a pressure that is greater due to the elastic force of the spring184, than a load applied by the two movable panel portions182. In addition, the spring184applies to the two movable panel portions182a force that allows the document9that is easy to lift from the platen glass15, such as a folded sheet(s) of document9or the book document9a, to be in close contact with the platen glass15.

In addition, when the two movable panel portions182contact a thick book document9aand are displaced upward over the retreat space120, they push the discharge tray123xfrom the retreat space120side toward the opposite side, namely, from below to above.

The discharge tray123xincludes a document receiving portion123aand movable side wall portions123b. The document receiving portion123aincludes a support shaft123cthat is rotatably supported by a bearing portion17aformed in the platen cover12, and the document receiving portion123acan pivot around the support shaft123c.

In addition, the movable side wall portions123bthat are disposed on the opposite sides of the document receiving portions123a, pivot integrally with the document receiving portions123a. The fixed side wall portions17cformed on the platen cover12overlap the movable side wall portions123band form walls that surround the retreat space120.

In the platen cover12of the image processing apparatus10x, the retreat space120is a space whose entire peripheral is surrounded by the two movable panel portions182, the discharge tray123x, and partition wall portions including the fixed side wall portions17c.

Upon receiving a force greater than the load from the retreat space120side, the discharge tray123xpivots to a side opposite to the retreat space120, namely, pivots upward.

As a result, when a thick book document9ais placed, the discharge tray123xis pushed by the two movable panel portions182that have retreated into the retreat space120, and is displaced to a side opposite to the retreat space120(seeFIG. 10).

Since the discharge tray123xcan be displaced in a direction of expanding the retreat space120, even in a case where the thick book document9ais placed on the platen glass15, it is possible to prevent the platen cover12from lifting.

In addition, even in a case where the two movable panel portions182are displaced to such an extent as to push up the discharge tray123x, a gap through which external light enters is minimized due to the action of the fixed side wall portions17cthat overlap the movable side wall portions123b.

The image reading portion11of the image processing apparatus10x, as is the case with the image reading portion11of the image processing apparatus10, can read the document image in the placement mode, the conveyance mode, and the insertion mode. It is noted that the image reading process in the insertion mode is executed when the specification number is specified.

In addition, the image reading device1includes a displacement sensor803xthat detects a displacement of the two movable panel portions182from the reference position into the retreat space120. In the following description, a state where a displacement of the two movable panel portions182into the retreat space120has been detected by the displacement sensor803xis referred to as a displacement detected state. It is noted that the displacement sensor803xis an example of the displacement detecting portion.

When the platen cover12is closed in a state where the book document9ais placed on the platen glass15, the two movable panel portions182are pushed by the book document9aand displaced into the retreat space120. Accordingly, it is also possible to say that the displacement sensor803xis a sensor configured to detect whether or not the book document9ais placed on the platen glass15.

For example, the displacement sensor803xmay be a photosensor that can detect whether or not a light blocking portion182aformed on one of the two movable panel portions182blocks light. The light blocking portion182a, in conjunction with the displacement of the panel portion182, is displaced between: a position where it blocks the light emitted from the photosensor; and a position where it does not block the light. In the image processing apparatus10x, the displacement sensor803xplays the same role as the feed sensor803of the image processing apparatus10.

The image processing portion84of the image processing apparatus10x, as is the case with the image processing portion84of the image processing apparatus10, executes the book document processing when the image data D0of the document9on the platen glass15has been obtained by the image reading portion11in a state where the displacement sensor803xhas detected that the two movable panel portions182were displaced into the retreat space120.

As understood from the above description, the image processing apparatus10xproduces substantially the same effect as the image processing apparatus10.

In the image processing apparatus10shown inFIG. 3toFIG. 5, the discharge tray123xof the image processing apparatus10xshown inFIG. 8andFIG. 9may be adopted. In addition, in the image processing apparatus10xshown inFIG. 8andFIG. 9, the discharge tray123of the image processing apparatus10shown inFIG. 3toFIG. 5may be adopted.

In the image processing apparatus10x, the two movable panel portions182may have the same link mechanism as the two document receiving portions123aof the discharge tray123in the image processing apparatus10. In this case, too, the two movable panel portions182can be displaced into the retreat space120.

In the document pressing portion18of the image processing apparatus10x, one of the two movable panel portions182may be omitted, and a movable panel portion182having the same length as the two movable panel portions182may be pivotably supported.

It is noted that the image processing apparatus of the present disclosure may be configured by freely combining, within the scope of claims, the above-described embodiments and application examples, or by modifying the embodiments and application examples or omitting a part thereof.