Abstract: Provided is a pressurizing member including a substrate, an elastic layer on the substrate, and a surface layer on the elastic layer, the surface layer containing a fluorine resin, wherein the surface layer has a surface resistivity of 1×1011[?/?] or less at a temperature of 25° C. when applying a DC voltage of 500 V, and a thermal conductivity ? in a thickness direction of the surface layer is 0.093 [W/(m·K)] or less.

Abstract: A backlight source packaging device is provided in the present disclosure, which belongs to the technical field of displays. The backlight source packaging device includes a bracket, a feeding mechanism, a cleaning mechanism, a cutting mechanism and a rotating mechanism, where the feeding mechanism is fixed to the bracket, which is configured to arrange a winding film; the cleaning mechanism is fixed to the bracket, which is configured to clean the winding film; the cutting mechanism is fixed to the bracket, which is configured to cut the winding film; the rotating mechanism is fixed to the bracket, which is configured to drive the backlight source to rotate so that the winding film winds around the backlight source, where the winding film can reach the rotating mechanism from the feeding mechanism successively through the cleaning mechanism and the cutting mechanism.

Abstract: A printer includes an apparatus body having a recording head for performing recording onto a sheet of paper. The printer also includes a unit body that is accommodated inside the apparatus body and has a path-forming surface formed at least on a portion of the periphery of the unit body. The path-forming surface forms a medium transport path. The unit body includes a plurality of openings that are in communication with a sound absorber disposed inside the unit body. The plurality of the openings are provided at least on a portion of the path-forming surface.

Abstract: According to embodiments, an image processing apparatus includes an erasing unit configured to perform an image erasing process on each of a plurality of conveyed recording media, and a control unit configured to control the image erasing process performed by the erasing unit. The control unit stops the image erasing process with respect to at least one of the recording media when a conveyance error occurs in the recording medium, determines a situation of the at least one of the recording media causing the conveyance error, restarts the image erasing process after the conveyance error is cleared, counts a number of the recording media conveyed to the erasing unit in accordance with a counting method according to the determined situation of the recording media, and continues the restarted image erasing process performed until the counted number of the recording media reaches a target number.

Abstract: A control unit first drives a photosensitive drum at a normal speed that is faster than a low speed, and the control unit subsequently changes the drive speed of the photosensitive drum from the normal speed to the low speed after a transfer belt is brought into contact with the photosensitive drum that is driven at the normal speed.

Abstract: A conveyor includes: a supporting member which supports the first and second roller units to allow the first and second rollers to take one of a first conveyance position and a first retracted position; a movable member which is movable between a first position where the first roller and the second roller take the first conveyance position and a second position where the rollers take the first retracted position; a cover member which is switchable between a closed state where the cover member is a part of the conveyance passage and an open state where a part of the conveyance passage is open; and an interlocking mechanism which is configured to move the movable member to the second position when the cover member is in the open state and moves the movable member to the first position when the cover member is in the closed state.

Abstract: An image recording apparatus includes: a housing including a frame and a conveyance path; a recording device which records an image on a sheet conveyed along the conveyance path; a first roller located upstream of the recording device; a second roller opposed to the first roller; a guide member pivotable between a first position for partly defining the conveyance path and a second position where the conveyance path is open; a roller holder coupled to the guide member and supporting the second roller; an urging portion which urges the second roller toward the first roller; and an engaging portion supported by the roller holder and configured to, when the guide member is located at the first position, be engaged with the frame to position the roller holder to a third position where the second roller contacts the first roller by an urging force of the urging portion.

Abstract: A supply device for a liquid developer includes plural supply members, and a control section, wherein each of the supply member has a cylindrical shape with recesses disposed on an outer peripheral surface, faces a developing member developing while rotating, draws up the liquid developer accommodated in an accommodation section while rotating, supplies the liquid developer to the outer peripheral surface of the developing member, and is arranged along a rotation direction of the developing member, and wherein the control section controls a rotation starting time for the plural supply members so that a position of a peak of a thickness of the liquid developer supplied to the outer peripheral surface of the developing member by a first supply member is different from a position of a peak of a thickness of the liquid developer supplied to the outer peripheral surface of the developing member by a second supply member.

Abstract: An apparatus for reducing registration errors in a media handling device. The apparatus including an image-bearing member having sheets individually pass across the image-bearing member. Each sheet pass corresponds to one of a series of iterations between the image-bearing member and the sheets. The image-bearing member is operatively coupled to a controller for regulation motion of the image-bearing member. The controller receives input signals representing at least one measured disturbance. Each disturbance being defined by a pattern of image-bearing member movement away from and substantially returning to a reference state of motion. A repetition of the pattern being coincident with at least one of the iterations, wherein based on the measured disturbance, the reference state and an indication associated with when the pattern will repeat, a modified signal is generated for the actuator to adjust the image-bearing member motion in coordination with the indication.

Abstract: A system to combine the transfer and fixing xerographic steps of a xerographic printer into one, as well as to eliminate the need for an electrical field for transfer. The image is transfixed directly from a photoconductor to the paper or other suitable substrate. Appropriate pressure is applied during this step to cold-pressure fix the toner on the paper, taking into account the type of substrate and type of toner. The cold pressure transfix can be done either directly from a photoreceptor, without an intermediate transfer belt (ITB), eliminating all electrostatic transfer subsystems and a fusing operation. Alternatively, for engines with an intermediate transfer belt (ITB), the cold pressure transfix could replace a needed second transfer and fuser system.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image, a movable endless transfer belt for transferring the toner image from the image bearing member onto a transfer material, and a transfer device for transferring the toner image from the image bearing member toward the transfer belt. The transfer device includes a transfer member for sliding on an inner surface of the transfer belt in contact with the inner surface, a supporting member for supporting the transfer member, and an urging member for urging the supporting member toward the transfer belt, wherein the transfer member contacts the inner surface of the transfer belt at a contact surface thereof without rotation relative to the supporting member during movement of the transfer belt. The supporting member is rotatable about a center axis during movement of the transfer belt, and the contact surface is convex with predetermined curvature toward the transfer belt.

Abstract: An electrophotographic (EP) printer for transferring a toner image to a receiver sheet has a tensioned rotatable transport web with a Young's modulus of at least 1 GPa. The transport web is wrapped around a compliant image-bearing member. A compressible, rotatable nip-forming member that is relatively less stiff than the image-bearing member is adjacent to the transport web on the opposite side thereof from the image-bearing member. A mount holds the nip-forming member against the image-bearing member, and permits the axis of rotation of the nip-forming member to move closer to or farther from the transport web. When the leading edge of the receiver on the web engages with the image-bearing member, the nip-forming member compresses. The axis of rotation of the nip-forming member translates by an amount less than the thickness of the receiver sheet minus the compression of the compliant coating of the image-bearing member.

Abstract: An image forming apparatus includes toner image forming units that are arranged in a line at two end portions and at an intermediate portion of the line, each of the toner image forming units forming a toner image; an image transfer body to which the toner images formed by the toner image forming units are transferred; pressing members that are linearly arranged so that each of the pressing members faces a corresponding one of the toner image forming units with the image transfer body therebetween, each of the pressing members applying a pressing force to the image transfer body; and a fixing unit that fixes the toner images on a recording member. The pressing forces applied by the pressing members that are disposed at the two end portions are smaller than the pressing force applied by the pressing member that is disposed in the intermediate portion.

Abstract: A transfer station is described for an EP printer that transfers a toner image to a receiver sheet carried on a rotatable transport web. The web is wrapped around a rotatable image-bearing member to define a transfer region. A nip-forming ski adjacent to the transport web on the opposite side thereof from the image-bearing member extends upstream of the transfer region. A ski mount causes the ski to press the transport web towards the image-bearing member. Therefore, as the receiver sheet moves with the transport web, the receiver sheet engages the image-bearing member upstream of the transfer region, causing the transport web to push against the ski to provide a selected nip-spacing between the image-bearing member and the transport web in the transfer region.

Abstract: The image forming method comprising: forming a toner image on an image carrier; transferring the toner image formed on the image carrier onto a recording medium; and transforming the toner image on the image carrier into a semi-film by applying a pressure. And the image forming apparatus comprising: an image carrier; a toner image forming unit configured to form a toner image on the image carrier; a transfer unit configured to transfer the toner image formed on the image carrier onto a recording medium; and a toner image transforming unit configured to transfer the toner image on the image carrier into a semi-film by applying a pressure to the toner image.

Abstract: A printing apparatus and method include a charging device positioned adjacent a photoreceptor that places a latent image charge on the photoreceptor. A donor device is adjacent the photoreceptor, and transfers marking material to regions of the photoreceptor that have received the latent image charge. In addition, a media path that is adjacent the photoreceptor causes at least one sheet of media to be placed on the photoreceptor and the marking material. A transfer assist blade that is also adjacent the photoreceptor, presses the sheet of media against the photoreceptor to cause the marking material to be transferred to the sheet of media. The apparatus also includes a controller that is operatively connected to the transfer assist blade. The controller causes the transfer assist blade to apply more pressure to leading and trailing portions of the sheet of media relative to the middle portion of the sheet of media.

Abstract: This is a baffle used in a transfer station of an electrophotographic marking system. The baffle has a series of air passages that, when these passages are opened, they apply pressure to a sheet of paper and push it upward against a belt or drum surface of a photoreceptor or photoconductor. The toner imaged photoreceptor then transfers the image to the paper that is in contact with it. From the transfer station, the paper with the transferred image is then moved to the fuser station where the image is fused to the paper. The baffle with air passages does not scratch the photoconductor surface as do the prior art systems. Also, the baffle has a much longer useful life than the more costly lift finger transfer blades previously used. A controller senses when a sheet enters the transfer station, senses the paper size, then activates a number of air passages to match the paper size.

Abstract: A transfer device includes: a transfer roll that transfers a toner image formed on an image holding body to a transfer subject medium; a first holding member that holds the transfer roll rotatably; a pressure contact member that brings, via the first holding member, the transfer roll into pressure contact with the image holding body; a second holding member that holds the first holding member swingably and movably; and a pressing member that produces a pressing force for bringing the pressure contact member into pressure contact with the first holding member and the second holding member in a state that the first holding member is inclined from the second holding member.

Abstract: Deflection recessed in a bow shape at the axial central portion in the longitudinal direction of the transfer member is avoided to prevent failure in image caused by the transfer nip being improperly forming at the central portion. The pressing force of the transfer member against an image bearing member resulting in failure in transfer is made uniform in the longitudinal direction. The transfer member forming the transfer nip are pressed toward the photosensitive drum at the central portion in the longitudinal direction or in the positions which are spaced apart toward the center from the ends to avoid the deflection of the transfer member.

Abstract: Disclosed is an image transfer roller (ITR) utilizing an elastomer crown, imaging devices and imaging apparatus using the disclosed ITR. According to one exemplary embodiment, an ITR includes a cylindrically shaped conductive shaft and an elastomer material covering all or a portion of the conductive shaft. The profile of the outer surface of the elastomer material includes a substantially quadratic crown profile.

Abstract: Deflection recessed in a bow shape at the axial central portion in the longitudinal direction of the transfer member is avoided to prevent failure in image caused by the transfer nip being improperly forming at the central portion. The pressing force of the transfer member against an image bearing member resulting in failure in transfer is made uniform in the longitudinal direction. The transfer member forming the transfer nip are pressed toward the photosensitive drum at the central portion in the longitudinal direction or in the positions which are spaced apart toward the center from the ends to avoid the deflection of the transfer member.

Abstract: Deflection recessed in a bow shape at the axial central portion in the longitudinal direction of the transfer member is avoided to prevent failure in image caused by the transfer nip being improperly forming at the central portion. The pressing force of the transfer member against an image bearing member resulting in failure in transfer is made uniform in the longitudinal direction. The transfer member forming the transfer nip are pressed toward the photosensitive drum at the central portion in the longitudinal direction or in the positions which are spaced apart toward the center from the ends to avoid the deflection of the transfer member.

Abstract: An image-forming device includes an image carrier belt, a roller, a transfer material transporting member, and a transfer roller. The image carrier belt carries an image. The transfer material transporting member transports a transfer material. The transfer roller transfers the image to the transfer material at a nip. The transfer roller includes a concaved portion formed on a peripheral surface thereof and a transfer material gripping portion that grips the transfer material in the concaved portion. The transfer roller is in contact with the roller via the image carrier belt. A first interaxial distance between a rotation axis of the transfer roller and a rotation axis of the roller as the transfer material is gripped is larger than a second interaxial distance between the rotation axis of the transfer roller and the rotation axis of the roller as the image is being transferred onto the transfer material at the nip.

Abstract: An image forming apparatus includes a latent image carrier on which a latent image is formed, a developer carrier being in contact with the latent image carrier and configured to develop the latent image by using a liquid developer that contains toner and a carrier liquid, an image carrier belt being in contact with the latent image carrier, where the latent image carrier is configured to transfer the latent image onto an area of the image carrier belt, a transfer roller including a concave section on a circumferential surface thereof and a sheet member being configured on a part of the circumferential surface other than where the concave section is wherein the transfer roller is configured to transfer the latent image onto a transfer material, and a control unit being configured to control the area of the image carrier belt being in contact with the sheet member via the transfer material.

Abstract: System and methods providing a plurality of fusers, and one or more radius profiled media handling transports for transporting media in a radius, in an image forming device. The system includes one or more of a plurality of fusers, and radius profiled media handling transport devices arranged in a fashion allowing for improved throughput of media while reducing operating costs. The plurality of fusers allows for the use of individual low capacity fusers that are equal to or less than the overall capacity of the image forming device. Media transport devices transport media on stretch belts across a radius of rollers with a means for providing an adhering force for stabilizing the media to the belt. The rollers are arranged along one side of the frame, along which the media is transported, and a frame may contain an air plenum so as to allow for the drawing of a vacuum through the rollers. The media transport device allows for optimizing a configuration of the image forming device.

Abstract: A transfer unit transfers a toner image formed on an image carrier onto a recording medium. A fixing unit includes a fixing roller and a pressure roller for fixing the toner image onto the recording medium by applying heat and pressure to the recording medium. At least one driving unit drives the fixing roller and the pressure roller. When stopping the fixing roller, a control unit controls the driving unit to stop the fixing roller such that the fixing roller and the pressure roller make a contact with each other at a contact position different from a previous contact position.

Abstract: An embodiment may be an image forming method, which comprises forming a latent image on an image carrier; developing the latent image with a toner to form a toner image on the image carrier; transferring the toner image; and applying ultrasonic vibration at one of the developing step and the transferring step. The toner comprises a resin particle and a release agent particle having a melting point in a range of 40 to 75° C. and the toner has Dp50 of 3.0 to 5.0 ?m.

Abstract: A transfer device is provided for an image forming apparatus designed such that toner images formed on a plurality of image bearing members are transferred one over another on a transfer body disposed in contact with each of the image bearing members with predetermined pressure and thus a toner image in two or more colors is formed on the transfer body. The transfer device includes a pressure varying mechanism which is capable of separating the transfer body from at least some of the image bearing members, and capable of varying transfer pressure between the image bearing members and the transfer body in contact with said image bearing members.

Abstract: In an image transferring apparatus of the invention, a transfer roller which comes in press contact with a sheet sent through a sheet conveyance path and transfers a toner image formed by an image forming section onto the sheet is constructed to be capable of being pulled out from a main body frame, and after pulling from the main body frame, when it is again mounted to the main body frame, it can be easily mounted to the main body frame without receiving a reaction force caused by a pressing force to bring the transfer roller into press contact with the sheet.

Abstract: A sheet transportation control method and an image forming apparatus are provided with which it is possible to prevent, by changing a set time, frequent detection of abnormal transportation. In an image forming apparatus 10 in which a paper jam (abnormal transportation) is detected based on the timing of detection of a sheet on which an image will be formed by each one of sheet sensors disposed along a transportation path along which said sheet is transported and based on a jam detection time (set time) stored in advance within a flash memory (storage part) 26 and paper transportation and image formation is stopped upon detection of a paper jam, when it is determined to change the jam detection time, a post-change jam detection time is determined and the jam detection time stored in the flash memory 26 is changed to thus determined jam detection time.

Abstract: Rollers including a tension roller are arranged in parallel. A pair of supporting members supports both ends of the rollers. A transfer belt is supported by the rollers. A biasing member applies a tension to the transfer belt by biasing the tension roller in a predetermined direction. The tension roller is movably supported in a straight-line direction. The biasing member is arranged in an area surrounded by the supporting members and the transfer belt in a direction of traversing from one supporting member to other supporting member.

Abstract: Deflection recessed in a bow shape at the axial central portion in the longitudinal direction of the transfer member is avoided to prevent failure in image caused by the transfer nip being improperly forming at the central portion. The pressing force of the transfer member against an image bearing member resulting in failure in transfer is made uniform in the longitudinal direction. The transfer member forming the transfer nip are pressed toward the photosensitive drum at the central portion in the longitudinal direction or in the positions which are spaced apart toward the center from the ends to avoid the deflection of the transfer member.

Abstract: There is provided an image forming apparatus comprising a developing device containing a toner having an average particle diameter of 2 to 5 ?m and a spherical degree of 1 to 1.2, and a transfer member which is pressed against the image carrier by a pressing force having a total load of 150 g to 1500 g and a surface load of 10 to 150 g/cm2 at the time of transfer.

Abstract: A moving unit is made to perform a contacting operation at least two times. The contacting operation includes relatively moving an endless belt and an image carrier so that the endless belt and the image carrier to come in contact with each other.

Abstract: An electrophotographic printing system having an apparatus for improving image fidelity is disclosed. The electrophotographic printing system includes a photosensitive drum, a first and second retractors and a paper presser. The first and second retractors position a sheet of printing paper within a first and second predetermined distances, respectively, from the photosensitive drum. The paper presser, which is operatively secured to the second retractor, presses the printing paper firmly against the photosensitive drum when developed toner images on said photosensitive drum are being transferred onto the printing paper.

Abstract: A transfer device includes a transfer roller that is rotatably provided facing an image carrying member, an urging device that urges the transfer roller in a direction that the transfer roller presses the image carrying member, and a regulating roller that is provided to a shaft commonly used with the transfer roller and presses the image carrying member to regulate a pressing force of the transfer roller that presses the image carrying member. The regulating roller is made of an elastic material.

Abstract: The present invention relates to a sheet feed device comprising a door for supporting one of the rollers of a feed roller pair for feeding a sheet, mounted on the apparatus main body so as to be opened or closed on the one end part side in the roller pair axis direction such that the one roller is pressured against the other roller of the feed roller pair provided in the apparatus main body at the time the door is closed, comprising: an outer door supported rotatably on the apparatus main body on the one side end part side in the feed roller pair axis direction; an inner door for supporting one of the rollers of the feed roller pair, supported rotatably with respect to the outer door on the one side end part side in the one roller axis direction.

Abstract: In a toner image forming apparatus, a contact member for pressing a work piece at a pressing position against a toner image on a movable transfer member so that the toner image is transferred from the transfer member onto the work piece is pressed against the transfer member while a test pattern toner image which is prevented from being transferred onto the work piece moves from a transfer position at which the toner image and the test pattern toner image are transferred onto the transfer member and a detecting position at which the test pattern toner image is detected to obtain a difference between the test pattern toner image on the transfer member and a desired test pattern image.

Abstract: An image forming apparatus includes a transfer roller pressed against an image carrier for transferring an image from the image carrier to a recording medium being conveyed via a nip between the transfer roller and the image carrier. The transfer roller is positioned in an angular range of less than ±90° from the top of said image carrier in the direction of rotation of the image carrier. In addition, the transfer roller has a greater diameter at its opposite end portions than at its center portion in the axial direction thereof.

Abstract: A device for transferring a pattern, especially micro- or nanostructures, from a stamp (1) to an object (2) comprises a first contacting means (11) with a receiving surface (13) for the stamp (1) and a second contacting means (20) with a receiving surface (23) for the object (2). A pressing means (10) is adapted to operate at least one of the contacting means (11, 20) for contacting the stamp (1) with the object (2). One contacting means (11, 20) comprises a base (21) and a holder (22). The holder (22) has a first end which defines one of the receiving surfaces (23) and a second opposite end which is pivotally connected to the base (21) in such a manner that the stamp (1) and the object (2) are automatically placed in a mutually parallel position when contacting each other.

Abstract: It is an exemplified object of the present invention to provide an image-forming device that can form a high-quality multicolor image at relatively low cost. To achieve the above object, the inventive image-forming device includes an endless belt that conveys a recordable medium; plural image-forming units that form a toner layer on the recordable medium via the endless belt; and a fixer that fixes the toner layer on the recordable medium, and a first pressing force applicable to the recordable medium by a last image-forming unit at a downstream side along a direction in which the recordable medium is conveyed among the plural image-forming units is greater than a second pressing force applicable to the recordable medium by another image-forming unit adjacent to the last image-forming unit at the downstream side among the plural image-forming units.

Abstract: An image forming apparatus of this invention includes an exposure unit for forming an electrostatic latent image on a photosensitive drum, a developing device for developing the electrostatic latent image on the photosensitive drum with a developing solution obtained by dispersing developer particles in a solvent, thereby forming a visible image, an intermediate transfer medium abutted against the photosensitive drum to transfer the visible image on the photosensitive drum thereto, a transfer unit having a backup member abutted against the intermediate transfer medium, the backup member urging a sheet against the intermediate transfer medium, thereby transferring a toner image on the intermediate transfer medium to the sheet, a detection unit for determining a type of the sheet to which the toner image is to be transferred by the transfer unit, and a control device for variably controlling a pressing force applied by the backup member to the sheet in accordance with the type of the sheet determined by the det

Abstract: An ablation image forming material is disclosed. In the image forming material the colorant particles are metal particles which are magnetized upon application of to magnetic force, a production method of the same, and an image forming apparatus.

Abstract: An electrophotographic machine including an image forming device configured to form a latent electrostatic image on a latent image carrier, a developing unit configured to develop a visible image from the latent electrostatic image on the latent image carrier with a liquid developer, and a pressure roller configured to apply pressure to an intermediate transfer medium disposed between the latent image carrier and the pressure roller. Further, a contact pressure between the intermediate transfer medium and the pressure roller is larger than a contact pressure between the intermediate transfer medium and the latent image carrier.

Abstract: A transfer device includes a transfer member that forms a nip part between a rotary image carrier carrying an image and the transfer member and that transfers the image on the image carrier to a transfer material passing through the nip part. The transfer member has on the transfer surface thereof notches slanting relative to a direction perpendicular to the transfer surface. The transfer device further includes a pushing member to push the transfer member to the image carrier so as to oppose to a pushing force from the transfer material to the transfer member, and a driving force transmission device that transmits a driving force to the transfer member such that the transfer surface of the transfer member moves at a circumferential speed different from that of the image carrier.

Abstract: An apparatus which cleans particles from a tracking region on a photoconductive drum. A spacer maintains the spacing between the photoconductive drum and a developer roller substantially constant. The spacer contacts the photoconductive drum in the tracking region. The cleaning member, mounted on a transfer roller, removes particles adhering to the tracking region so as to ensure that there is no build up of particles in the tracking region changing the spacing between the photoconductive drum and the developer roller.

Abstract: An image forming apparatus comprises an image bearing member for bearing an image, and a movable member which is abutted against the image bearing member and onto which the image on the image bearing member is transferred. The movable member includes a substrate, a sheet-like member, and an elastic layer disposed between the substrate and the sheet-like member and compressed to a predetermined thickness before the movable member is abutted against the image bearing member.

Abstract: A color image forming apparatus having a plurality of image forming units, a first attraction unit and a second attraction unit for attracting a recording sheet to a transport belt, and a controller for operating the first attraction unit when a first mode is set for forming a color image using all of the plurality of image forming units, and for operating the second attraction unit when a second mode is set for forming a single-color image using only one of the image forming units. In another embodiment, a controller sets a transfer pressure at a first pressure for each of the plurality of image forming units when the first mode is set and at a second pressure, which is higher than the first pressure, for the image forming units not being used to form the single-color image when the second mode is set.

Abstract: There are provided an image transfer apparatus and an image forming apparatus which can form an image of excellent quality by controlling speed variations of an image carrier and an intermediate transfer body generated by an external force. When the front end of a recording medium enters the nip area provided between the intermediate transfer body and a bias transfer roll and the rear end of the recording medium leaves the nip area, an impact force is applied to the intermediate transfer body and the bias transfer roll. The bias transfer roll swings, due to such impact force, in the direction parallel to the traveling direction of the recording medium to enter the nip area. As a result, a transitional load variation to be applied to the intermediate transfer body with such impact force is absorbed by springs to prevent rotating variation of the intermediate transfer body and the image carrier.

Abstract: A paper pressing force controller of a printer includes a pressing roller that contacts a transfer roller for receiving a paper sheet therebetween. Guide rollers supply the paper sheet between the transfer roller and the pressing roller and a pressure sensing unit senses the pressure variations according to the thickness variations of the paper sheet supplied between the guide rollers. A pressure changing unit controls a pressing force of the pressing roller against the paper sheet by moving the pressing roller vertically with respect to the transfer roller.