Abstract: An image reading apparatus capable of changing a main reading unit at an appropriate time point such that a plurality of reading units can be equally used, and a method of controlling the same. The image reading apparatus includes an automatic document feeder, a first reading unit to read a first side of a document fed by the automatic document feeder and to function as a main reading unit, a second reading unit to read a second side of the document fed by the automatic document feeder; and a control unit to change the main reading unit from the first reading unit to the second reading unit if the number of times La of usage of the first reading unit reaches a reference value.

Abstract: When a cover portion covers a document table, a document transporting unit is positioned relative to a reinforcing member in the horizontal direction so that the document transporting unit is movable in the vertical direction, and a first vertical positioning member comes into contact with the document table of a reading unit or the periphery thereof to position the document transporting unit in the vertical direction based on the position of the document table. A document height regulating member is positioned relative to the reinforcing member in the horizontal direction so as to be movable in the vertical direction, and a second vertical positioning member comes into contact with the document table to position a regulating member in the vertical direction based on the position of the document table.

Abstract: A device which can be used to handle documents which can be written to and erased can include a scan head which can output a first light source for scanning a document and a second light source for erasing an image from a printed document. In one embodiment, the device can further include a third light source for writing or imaging a pattern onto a page.

Abstract: An image reading apparatus is disclosed that includes a contact glass on which a document is placed; an imaging device configured to image a document image based on light reflected from the document through the contact glass; plural line image sensors arranged along a main scanning direction at positions where the document image is imaged and configured so that end portions of the line image sensors adjacent to each other similarly read same image data imaged at an overlapping area; a transmitted light quantity reduction unit disposed in the overlapping area on the contact glass and configured to reduce transmitted light quantity of a light transmitted through the contact glass; and a signal correction device configured to correct the signal intensity of the image data similarly read by the line image sensors adjacent to each other.

Abstract: An image processor includes a reading unit that moves a scanning optical system toward a reference white sheet to read the reference white sheet from a direction along which the scanning optical system returns to the carried document reading glass before reading one sheet of a document mounted on a carried document reading glass by an automatic document feeding unit in a sheet document reading mode of forming an image of the document carried by the automatic document feeding unit by an image sensor through the scanning optical system facing the carried document reading glass.

Abstract: An original transport and reading apparatus is provided with an original transport portion that transports an original, an original reading portion that reads the original transported by the original transport portion through a reading region of a reading glass, and a control portion that controls the original transport portion. The control portion executes foreign matter removal at the reading region of the reading glass by controlling the original transport portion so as to cause the original to advance in a reverse direction to a transport direction of when the original is being read and causes the original to contact at least the reading region of the reading glass.

Abstract: The invention relates to a sheet-fed scanner (300) comprising: an illumination device for emitting a luminous flux covering several spectral bands which is intended to illuminate a sheet (204) to be scanned, a focussing device (150), and a detection module (360) comprising a sensor (164) which comprises a plurality of rows (166, 168, 170) of sensitive elements, each sensitive element being provided to deliver an electrical energy that is proportional to the intensity of the luminous flux received, and each row being provided to have its sensitivity peak for one of said spectral bands, the focussing device being provided to focus, onto each of the rows, part of the luminous flux reflected by said sheet, the sheet-fed scanner (300) being characterised in that the detection module (360) comprises a non-prismatic spectral shift device (305) for shifting each part of the luminous flux thus focussed, parallel to said rows (166, 168, 170), the shift being different for each row (166, 168, 170).

Abstract: Restriction information on a total colorant amount for a medium is obtained. Patches at grid points in a color space corresponding to a plurality of colorants at which the total colorant amount falls within a restriction represented by the restriction information, and a patch at a point surrounded by the patches are generated. Color values are obtained by measuring the colors of the patches printed on the medium. It is determined based on a color prediction value between the grid points whether the measured color values are appropriate, and if so, a color value at a grid point at which the total colorant amount exceeds the restriction is estimated based on the measured color values. A color separation table is created based on the measured color values and the estimated value.

Abstract: An image reading apparatus is provided that can prevent image streaks due to dirt, stain or the like from being produced in an image of an original that is read while being conveyed. The image reading apparatus (A) includes an ADF (40) having a scanner unit (59) incorporated therein and comprised of a cylinder (60) having an outer peripheral surface thereof on which a plurality of read pixels (61) are arranged in a matrix. In reading an original (D), the scanner unit is rotatably driven in an original conveying direction at a circumferential speed approximately equal to an original conveying speed, and reads image information on the original passing through an image reading position (P1).

Abstract: When a monochromatic copy mode is to be executed, a control section sets a read mode in a scanner section so as to enable the scanner section to read an image at high speed by means of only a line sensor K, sets in an image processing section an image process that can print monochromatic image information, which is sent from the scanner section, with a single black color in the printer section, and sets in the printer section a monochromatic print mode that can print a black image at high speed, thereby controlling a monochromatic copy operation.

Abstract: A gap indicator device is rotatably locked to an auto document feeder openably and closably installed to a scanner device of an image scanning apparatus, is rotated by being pressed by the scanner device, and includes a pointer or a scale to indicate a state of an image reading gap, as a gap between a platen guide and an image reading portion, through which an original document passes. The pointer or the scale is located at a position where it can be visually recognized from above when a cover of the auto document feeder is opened.

Abstract: There is disclosed an image capture apparatus that facilitates fast, easy and convenient image capture of the two apposing pages of hard to scan bound documents such as thick books. The image capture apparatus has special design features that conveniently and properly positions bound documents to enable capturing distortion-free images without damage to the binding. In one preferred embodiment the invention facilitates the use of a digital image capture module such as a digital camera or digital video camera in performing an equivalent function to a flatbed scanner in recording digital images. In another preferred embodiment the invention facilitates the use of a regular camera in recording photographic images of the bound document. In yet another preferred embodiment the invention facilitates the use of a flatbed scanner in recording digital images.

Abstract: An image reading apparatus reads an image of a document. An image reading section reads an image of a document. A scanning mechanism causes the image reading section to move relative to the document when the document is at rest. When the image reading section is at rest, a document feeding mechanism causes the document to move relative to the image reading section. A shutter moves to a first position where the shutter opens, allowing the image reading section to read the image of the document when the document moves relative to the image reading section at rest. The shutter moves to a second position where the shutter closes, allowing the image reading section to read the image of the document when the image reading section moves relative to the document at rest.

Abstract: A measuring apparatus for scanning moving, preferably sheet-like, printing materials in a printing material-processing machine, such as a press for processing sheet material. The apparatus has a measuring device which can be moved, at least in the transport direction of the printing materials. The measuring apparatus is set up in such a way that, during a measuring operation, the measuring device is moved over the moving printing material in the transport direction of the printing material with a differential speed relative to the transport speed of the printing material.

Abstract: An image reading device includes a reference member, a reading unit, a first reference value setting unit, a detecting unit, a second reference value setting unit, a determining unit, and a pixel value setting unit. The reading unit obtains image data and reference data. The first reference value setting unit sets a first reference value based on the reference data. The detecting unit detects a usage state of the reading unit. The second reference value setting unit sets a second reference value in accordance with the usage state. If the determining unit determines that the first reference value is in a predetermined condition, the pixel value setting unit sets a pixel value based on the image data and the first reference value; otherwise, the pixel value setting unit sets the pixel value based on the image data and the second reference value.

Abstract: An image reading device includes an image reading section, a frame, and an operating unit. The image reading section is configured to obtain image data by reading an image carried on a document. The frame supports the image reading section. The operating unit has an operating section including a plurality of input keys adapted to receive an input operation for controlling the image reading section, and an operating unit body supporting the operating section for displacement between a drawn-out position in which the input keys are exposed to outside and a housed position in which the input keys are housed inside. The operating unit is supported by the frame.

Abstract: A transfer member to transfer a document at different transfer speeds according to transfer sections of a document transfer path includes a first transfer roller and a second transfer roller, both of which are respectively mounted at upstream and downstream sides of the document transfer path, and a driving unit to drive the first and second transfer rollers such that the speed of the second transfer roller is higher than that of the first transfer roller under the control of a control unit is further included. The control unit reads an image pattern on a test document using a read device, acquires speed compensation information to compensate for a transfer speed of the transfer member, and controls an operation of the transfer member according to the speed compensation information at the time of transferring the document.

Abstract: An image reading apparatus reads a document on a line-by-line basis by using a reading unit. The image reading apparatus includes a modulation unit configured to modulate a clock signal at a predetermined period, a trigger signal generation unit configured to generate trigger signal for reading one line in the reading unit, a driving signal generation unit configured to generate a driving signal of the reading unit based on the clock signal output from the modulation unit and the trigger signal, and an output unit configured to change output timing of the driving signal within a range of the predetermined period each time the trigger signals are output predetermined times.

Abstract: An image scanning apparatus includes a reversal tray on which printable media are temporarily stacked, and a reverse roller installed inside a main body immediately before the reversal tray at a junction between the reversal tray and an end of a second moving path, which is driven in both clockwise and anti-clockwise directions by power transmitted via a discharge roller to guide one of the printable media towards and away from the reversal tray along a second moving path, wherein a feeder, a pick-up roller, a scanning unit, a discharge tray, and transport rollers are installed on a first moving path in order to scan images from one side of the printable medium, and the reversal tray and the reverse roller are installed on the second moving path in order to scan images from the other side of the printable medium.

Abstract: During a sheet-through operation, for a first original, a shading operation is performed to acquire white data and a light-quantity measuring operation is performed to acquire a reference value. For subsequent originals, only the light-quantity measuring operation is performed to acquire a subsequent light quantity. If the reference value and the subsequent light quantity differ greatly, the shading operation is performed at this time point to acquire new white data. The sheet-through operation is not stopped when the shading operation is not performed and the sheet-through operation is stopped when the shading operation is performed.

Abstract: A duplex document scanning apparatus and method thereof are described. The duplex document scanning apparatus includes a first image sensor, a second image sensor, a switch module, a data conversion unit, and a scanning control device. The first image sensor senses the first analog image signal and the second image sensor senses the second analog image signal. The switch module switches the first image sensor and the second image sensor to select the first analog image signal and the second analog image signal. The data conversion unit converts the first and second analog image signals to generate first and second digital image signals. The switch control module of scanning control device generates a switch signal to control the switch module. The scanning control device has a switch control unit and processes the first digital image signal and a second digital image signal.

Abstract: An image reading device according to one aspect of the invention comprises: a conveying unit configured to convey a recording medium; a first transmissive portion having a first surface that allows the recording medium to pass the first surface; a second transmissive portion having a second surface on which a recording medium is allowed to be placed; an image reading unit comprising a line sensor extending in a first direction and movable on a second path, the second path continuously extending below the first transmissive portion and the second transmissive portion; and a driver configured to move the image reading unit on the second path. A relative distance between the line sensor and the first surface changes in the second path below the first transmissive portion. The recording medium can be read at positions having the relative distances different one another.

Abstract: An image reading apparatus capable of continually conveying a plurality of originals in a stable manner while cleaning a contact glass of an image sensor and reducing streaks occurring in read images. An image sensor reads an original image via a contact member which the conveyed original may contact. A cleaning member, being provided on a turning member which is able to rotate or swing and disposed at a position opposing the image sensor, cleans the contact member's surface which the original may contact. The turning member is turned by a driving unit. A controlling unit controls the driving unit to turn the turning member so that cleaning of the contact member is performed by the cleaning member after the original has passed an image reading position of the image sensor and before a subsequent original reaches the image reading position.

Abstract: An image reading apparatus includes: (i) a capturing device for capturing an original image of a source document; (ii) a moving device for moving one of the capturing device and the source document relative to the other; (iii) a first region processor for causing the moving device to position the capturing device in a first capturing position, so as to obtain a first pixel-related data relating to pixels present in a first region of the source document; (iv) a background-color-basis correcting-value determiner for determining a background-color-basis correcting value, based on the first pixel-related data; and (v) a second region processor for causing the moving device to position the capturing device in a second capturing position, so as to obtain a second pixel-related data relating to pixels present in a second region of the source document.

Abstract: A method for providing a visible reference marker on a scanning unit for orienting an item to be scanned or copied includes the steps of emitting a light from a light source, guiding the light to a scanning unit having a contact glass scanning surface, and redirecting the light to define an illuminated reference marker substantially adjacent to the contact glass. A reference marker assembly for accomplishing that method is provided, including a light source, a waveguide for guiding light emitted from the light source to a scanning unit having a contact glass, and a redirector for redirecting the light to define an illuminated reference marker adjacent to the contact glass, for orienting an item to be copied or scanned. The light source may be a light emitting diode, and the redirector may be a light diffuser for redirecting the collected light to define an illuminated reference marker adjacent to the contact glass.

Abstract: It is a first aspect of the present invention to provide a scanning device that includes a first imaging device adapted to convert contents of a first surface of a medium to a digital representation of the contents of the first surface of the medium, a scanning path adapted to guide the medium adjacent to the first imaging device, a first output path for guiding the medium to a first output tray, the first output path connected to the scanning path, a second output path for guiding the medium to a second output tray, the second output path connected to the scanning path, and a diverter guide adapted to direct the medium from the scanning path to one of the first output path and the second output path.

Abstract: An image reading and recording apparatus has: a carriage for mounting a recording head; a reading unit which reads an original document; a conveying roller arranged on a conveying path which is used in common for recording paper and the original; and a platen arranged so as to face the recording head. The reading unit is movable between a reading position on an upper side of the conveying path and a retracting position on a lower side of the conveying path. The platen can relatively and independently move for the reading unit.

Abstract: An image reading apparatus including a first image reader for reading the front side of document, and a second image reader configured to read the reverse side of document. The apparatus also includes a storage device to store first image data read by the first image reader and second image data read by the second image reader, and a writing controller for writing the first image data and the second image data in parallel to the storage device. A reading controller then reads the first image data and the second image data sequentially from the storage device, and an image processor processes the first and second image data. An image converter then converts the format of the first image data and/or the second image data to be the same.

Abstract: An image reading technique is disclosed that involves acquiring document image data including more than one set of page image data, reading an image located at a predetermined page position from the acquired set of page image data, recognizing the read image of the predetermined page position and converting the recognized image into text data, and assigning page number order to the set of page image data according to value information represented by the converted text data.

Abstract: An image reader and an image forming apparatus are provided. The image reader includes a stationary document scanning device; a moving document scanning device; a scan window; a document cover covering the scan window and comprising an opening located at a position facing the scan window; a document feeding mechanism which is disposed at the document cover and feeds a document through the opening in the document cover and onto the scan window when the document is to be scanned by the moving document scanning device; an image pickup device configured to read an image from the scan window; and a controller which detects edges of the stationary document based on image data read by the image pickup device, and performs an image data defining operation to determine image data, which is included within the detected edges of the document, as exact image data.

Abstract: An image scanning device including: a conveyance path which conveys originals; a first scanning means and a second scanning means which are placed such that they sandwich the conveyance path; and a white reference member used for adjusting the white levels of the scanning means; wherein at least one of the first scanning means, the second scanning means and the white reference member is movable; the first scanning means and the second scanning means can scan the same surface of said white reference member since the first scanning means or the second scanning means is moved or the white reference member is moved.

Abstract: A document reading apparatus includes a conveying unit configured to continuously convey a document having a series of sheets along a conveyance path, a reading unit configured to obtain image data by reading a sheet at a predetermined reading position, a storage unit configured to store the image data obtained by the reading unit, and a transfer unit configured to transfer the stored image data to a transfer destination. The transfer satisfies a relationship X+Y?Z>X, wherein X represents a reading time required for the reading unit to read said sheet, Y represents an interval time between an end of reading said sheet and a beginning of reading a next sheet of the series, and Z represents a transfer time required for the transfer unit to transfer the image data stored in the storage unit to the transfer destination. A related method is also disclosed.

Abstract: In an image scanning apparatus, documents on a document tray are transferred one by one, and an upper surface height of the documents is lowered to turn off a height detection sensor. Different kinds of control modes are performed according to a document scanning mode. In an image-quality-priority scanning mode, a transfer unit suspends transfer of the document, the document tray is elevated until the upper surface height reaches a target height that is higher by a predetermined distance after the height detection sensor is turned on, and the transfer unit resumes the transfer of the document. In a speed-priority scanning mode, while the transfer of the document is continued by the transfer unit, the document tray is elevated until the document tray reaches the target height.

Abstract: A document feeding section, a CCD which reads one side of a document conveyed by the document feeding section, a CIS which reads the other side of the document, a reversing mechanism which reverses the document, a document discharging tray, a first document conveying passage which connects a document tray and the CCD, a reverse document conveying passage which connects the CCD and the reversing mechanism, a re-conveying document conveying passage which connects the reversing mechanism and the first document conveying passage, and a discharging document conveying passage which branches out from the reverse document conveying passage and is connected to the document sheet-discharging tray, are provided, and a CIS which reads the other side of the document is provided in the discharging document conveying passage.

Abstract: An image reading device to read an image carried on a document, including: an image reading section to read an image carried on a document; a polygonal member, mounted to face the image reading section, and spaced from the image reading section at a predetermined distance, the polygonal member includes a document feeding flat surface which faces the image reading section when the document is fed thereon, a white flat surface, and a black flat surface; a light source to emit light rays onto the image carried on the document, and onto the polygonal member when the document is not fed; and a control section to control an amount of the light rays emitted from the light source; wherein the control section corrects an amount of light rays concerning the white color and the black color, based on the amount of the light rays read by the image reading section.

Abstract: A document reader comprises line sensors that are staggeredly arranged and read a white reference plate to obtain a white reference read value A, and a white reference average value AA is determined from value A for each line sensor. The line sensors read another white reference plate placed on a document support plate to obtain a white reference read value B, and a white reference read average value BB is determined from value B for each line sensor. A sensitivity effect coefficient C for each line sensor is determined by dividing BB by AA. Using the line sensors, there are obtained a document read value E for each line sensor by reading an illuminated document on the document support plate, a white reference read value Aa by reading with the white reference plate before reading the document, and a black reference read value D by reading the white reference plate under a condition that an illumination is turned off before reading of the document.

Abstract: An imaging apparatus includes an image capturing system. A controller is communicatively coupled to the image capturing system. A scanner body has a scanner opening. The image capturing system is located adjacent the scanner opening. A document planar member is positioned across the scanner opening. The document planar member is communicatively coupled to the controller. The document planar member has a transparent state wherein the document planar member is clear and having a translucent state wherein the document planar member is translucent. The controller executes program instructions to control the document planar member to display scan operation related indicia formed by controlling a first portion of the document planar member to be in the transparent state and controlling a second portion of the document planar member to be in the translucent state.

Abstract: In an image reading apparatus, a retreat control device moves a conveyance target through a conveyance mechanism, when a stop operation is performed by a stop control device, in an opposite direction to an image reading direction to a position further from a restart reference position set by a position setting unit. A reading control device again moves the conveyance target, which has been moved by the retreat control device, at a constant speed in the image reading direction under a predetermined condition; inputs a line start signal to a reading unit when an offset time set by a time setting unit has elapsed from a time point when the conveyance target reaches the restart reference position; and periodically inputs a line start signal to thereby cause the reading unit to perform a reading operation from a point; where the reading unit is located when the offset time has elapsed.

Abstract: Depending on processing to be executed, the processing is prevented from being restricted even if a particular image is included in image data. There is provided an image processing apparatus comprising an authentication section 67 which distinguishes a user; a particular-image judgment section 63 which detects particular images from inputted image data and judges whether or not the number of the particular images exceeds a threshold; and a threshold determination section 66 which determines a threshold according to the user and processing to be executed; and a control section 7 which restricts the processing to be executed when the number of the particular images exceeds the threshold. Depending on the importance degree of the security of the processing to be executed, the threshold determination section 66 lowers the threshold as the importance degree is higher and raises the threshold as the importance degree is lower.

Abstract: The invention claimed is a novel front feed document imaging device input tray which accommodates varying types and widths of media by providing front feed capability in a single tray attachment, and which tray can pivot out of the way of the document path by virtue of torsion springs when the user wishes to alternate media types. The input tray may be locked into position depending upon the user's requirements.

Abstract: For an image-capturing unit having a light source and mirrors directing light reflected from a scanned document into a lens condensing the light onto a photoelectrically converting image sensor, a synthetic resin housing. The housing is composed of an open-ended upper frame having a top plate from which sidewalls extend, encompassing an internal space. A mounting surface for anchoring the light-source is formed on the upper side of the upper-frame top plate, and formed on the lower side of the upper-frame top plate is a pedestal on which the lens is supported. Mirror-support projections are formed on the lower side of the upper-frame top plate, or on the upper-frame sidewalls, to support the mirrors from below the lens. With this housing, the influence of heat from the light source on the optics is minimized, improving the mirrors' positional accuracy.

Abstract: An image reading and recording apparatus includes a trigger arm configured to start transmission of a drive to a paper feed unit in accordance with the position of a carriage. The trigger arm includes a first lever portion for feeding a recording sheet in a state in which a cap is separated from a recording head and a second lever portion for feeding a document in a state in which the cap is in contact with the recording head.

Abstract: A line image sensor reads an image of a reading position on a contact glass by a plurality of lines in a main-scanning direction. A replacing unit replaces, when there is a pixel whose read values of read data from a plurality of read lines in a same main scanning period are smaller than a predetermined black threshold and an adjacent pixel whose two arbitrary read values have a difference larger than a predetermined threshold near the pixel, and if the pixel remains at a same pixel position in a predetermined number of continuous main scanning periods, replaces read data of the adjacent pixel and a predetermined number of subsequent pixels with white pixel data.

Abstract: An apparatus and method for scanning documents such as ID cards and bank checks that includes hinged cover and base assemblies. The base includes motor driven drive rollers for conveying a document along a paper path defined between the cover and base. The cover includes a plurality of pinch rollers forming part of a floating deck that is carried by cover structure and which is spring biased towards the base assembly. Two side-by-side scanning regions are provided, one of which is configured to scan flexible documents, the other of which is configured to scan rigid media such ID cards. Sensors detect the position of the document. A solenoid driven, replaceable ink stamp imprints a document to indicate that it has been scanned. A weight biased diverter is deflected by rigid documents to enable exit through a slot. An entrance guide includes an offset guide wall to improve feeding.

Abstract: An image reading apparatus including an image reading portion reading an image of an original placed on an original stand; an original cover pressing the original on the original stand; a plurality of hinge portions pivotally supporting the original cover with respect to the image reading portion; a plurality of opening and closing drive portions arranged in the plurality of hinge portions, respectively to open-drive and close-drive the original cover; and a control portion open-driving and close-driving the plurality of opening and closing drive portions based on different drive profiles, respectively.

Abstract: Disclosed herein is a scanner device which scans a predetermined scan object and generates image data, the scanner device including: an image sensor which converts an optical image of the scan object into corresponding image data; a movement unit which moves a carriage having the image sensor in a sub-scan direction; a first control unit which controls the movement unit by a first control process; a second control unit which controls the movement unit by a second control process different from the first control process; and a selection unit which selects the first or the second control unit according to setting contents relating to a scan.

Abstract: An image scanner in which in scanning an image of a document placed on a scanner body, an image scanning device moves and scans the image of the document. In scanning an image of a document fed by a document feeder to the scanner body, the image scanning device moves to a predetermined scanning position and then scans the image of the document in the scanning position. When the image scanning device arrives at the scanning position, the image scanning device is pressed against a stopper that is positioned relative to the document feeder.

Abstract: An image-reading processing apparatus is connected to an image reading apparatus being capable of reading both surface images of a document, including a storage unit and a control unit, wherein the control unit includes a double-face reading control unit that controls the image reading apparatus to scan both the surfaces of the document, a coordinate acquiring unit that acquires a coordinate group of a position serving as an edge candidate of the document based on a grayscale value in image data of each of the surfaces read by the double-face reading control unit, a straight line detecting unit that detects a straight line group corresponding to an edge portion of the document based on the coordinate group acquired by the coordinate acquiring unit, a straight line inverting unit that inverts the straight line group detected by the straight line detecting unit, and a straight line selecting unit that determines the straight line group suitable for the edge portion from the document in the straight line group d

Abstract: The invention claimed is a scanner which allows for any type of media, including embossed credit cards, with a thickness in the range of 0.1 mm to 1.5 mm to be inserted into the media path and remain in constant contact with the CIS as a result of a spring loaded roller, gear, and cantilever system. The input process, called a “kick start” method, allows for momentary lowering of the roller, and return, as it spins to grasp the media and continue pulling the media through the scan path. This apparatus stores energy provided by the motor within its spring and gear system, thus requiring less energy from the motor, and reduces manufacturing costs.

Abstract: The present invention relates to an automatic sheet-feeding scanning apparatus having a movable guide rib device. The automatic sheet-feeding scanning apparatus includes a flatbed scanner and an automatic document feeder. The movable guide rib device is mounted in a housing of the flatbed scanner and includes a guide rib structure, at least one hollow portion, a plurality of elastic members and a fixing plate. The guide rib structure is movable upwardly or downwardly so as to avoid document damage even if the document is relatively large-sized.