Abstract: A sheet conveying device is provided in a sheet discharge portion of an image forming apparatus. A curved path and a reverse conveyance path are formed within the sheet conveying device. An outer guide rib and an inner guide rib are provided to a conveyance guide forming a lower-side guide surface of the curved path. The inner guide rib is lower than a reference straight line connecting a pressure contact point of a discharge roller pair to a rotary roller, and the outer guide rib is higher than the reference straight line.

Abstract: A sheet feed apparatus has sheet tray, sheet conveyance path, sheet feed roller, lift plate, and guide wall. Sheet feed roller is disposed, downstream of sheet tray in sheet conveyance direction, above central portion of sheet tray in sheet width direction perpendicular to sheet conveyance direction, so as to face central portion. Lift plate is movable upward and downward to allow sheet to contact with sheet feed roller. Guide wall is disposed downstream of lift plate in sheet conveyance direction and spaced from lift plate with predetermined gap, to guide the conveyed sheet in diagonally upward direction intersecting placing surface of sheet tray. Both end portions in sheet width direction in front edge portion, of lift plate, facing guide wall are provided with end guide surfaces, respectively, which are inclined upward relative to central portion in sheet width direction.

Abstract: An image forming apparatus includes a main body, a developing device, a support frame, a developer case, and an intermediate hopper. The support frame selectively positions the developing device to a detachment position and a developing position. The intermediate hopper includes a first hopper, a second hopper, and a third hopper. The first hopper receives developer from the developer case through a developer inlet port. The second hopper has a developer outlet port, through which the developer is supplied to the developing device. The upper and lower end portions of the third hopper are respectively connected to the first and second hoppers. Parts where the first to third hoppers are connected one another are rotatable in directions that allow the support frame to move.

Abstract: A sheet feeding apparatus includes a sheet tray, a sheet feeding roller and a pair of link members. The sheet tray constitutes a loading surface. The sheet tray includes a tray main body and a lifting plate. The tray main body is openable and closable with respect to the wall portion. The lifting plate has a pair of first fulcrum portions disposed upstream of the sheet feeding roller. The downstream side of the lifting plate is rotationally movable up and down around the first fulcrum portions. The tray main body has a pair of second fulcrum portions . The second fulcrum portions are configured to be a pivot point for the opening and closing operation of the tray main body. Each of the pair of link members is coupled to the first fulcrum portion and to the wall portion.

Abstract: A sheet feed apparatus has sheet tray, sheet conveyance path, sheet feed roller, lift plate, and guide wall. Sheet feed roller is disposed, downstream of sheet tray in sheet conveyance direction, above central portion of sheet tray in sheet width direction perpendicular to sheet conveyance direction, so as to face central portion. Lift plate is movable upward and downward to allow sheet to contact with sheet feed roller. Guide wall is disposed downstream of lift plate in sheet conveyance direction and spaced from lift plate with predetermined gap, to guide the conveyed sheet in diagonally upward direction intersecting placing surface of sheet tray. Both end portions in sheet width direction in front edge portion, of lift plate, facing guide wall are provided with end guide surfaces, respectively, which are inclined upward relative to central portion in sheet width direction.

Abstract: A sheet tray includes a tray section. A rear end portion of the tray section capable of supporting an upstream side of a sheet in a direction of conveyance of the sheet extends in a width direction of the sheet transversely of the direction of conveyance of the sheet. Both ends of the rear end portion of the tray section in the width direction of the sheet are raised upward perpendicularly to a placement surface relative to the middle of the rear end portion in the width direction of the sheet.

Abstract: A drive mechanism of the present invention includes: a housing part composed of a first resin cover and a second resin cover; a first sheet metal member housed in the housing part; a first rotation transmission wheel group disposed on the first sheet metal member on a side directed to the first resin cover; a second rotation transmission wheel group disposed on the first sheet metal member on a side directed to the second resin cover; a positioning part rotatably supporting a first rotation transmission wheel of the first rotation transmission wheel group; and a pin member positioned by inserting into the positioning part via the first resin cover.

Abstract: A drive mechanism of the present invention includes: a housing part composed of a first resin cover and a second resin cover; a first sheet metal member housed in the housing part; a first rotation transmission wheel group disposed on the first sheet metal member on a side directed to the first resin cover; a second rotation transmission wheel group disposed on the first sheet metal member on a side directed to the second resin cover; a positioning part rotatably supporting a first rotation transmission wheel of the first rotation transmission wheel group; and a pin member positioned by inserting into the positioning part via the first resin cover.

Abstract: A color printer 1 has a rotary type developing device 30 which rotated by an input gear 46 that receives power from a motor, and a plurality of developing units 13 supported on a frame 28. The plurality of developing units 13 accommodates toner of different colors therein. The frame 28 a first annular gear 29 being configured to be rotated by the input gear 46 and a second ring-shaped annular member 32 having a larger external diameter than the first annular gear 29. The second ring-shaped annular member 32 is disposed adjacent to and on the outer side of the first annular gear and on the same rotational axis.

Abstract: An image forming apparatus includes a first sheet conveying passage that conveys a sheet through an image forming section. A sheet-discharging roller is on an outlet side of the first sheet conveying passage and can rotate in opposite directions. A second sheet conveying passage has an inlet connected to the first sheet conveying passage downstream from the image forming section and an outlet connected to the first sheet conveying passage upstream from the image forming section. A controller controls double-sided printing by causing the sheet-discharging roller to rotate forward to advance the sheet outside the sheet-discharging roller, and then to rotate in reverse to execute a switchback for transporting the sheet to the inlet side of the second sheet conveying passage and then to return the sheet to the upstream of the image forming section. An assisting mechanism adjusts a posture of the sheet to assist the switchback.

Abstract: A rotary developing device 30 is provided in an image forming device that is rotated by an input gear 46. The rotary developing device 30 has a plurality of developing units 13, a frame 28, and a rotation stop mechanism 50. Each of the plurality of developing units 13 house toner of one of the colors, and develops at a predetermined developing position. The frame 28 includes a support portion 36 that supports the plurality of developing units 13 and has a rotation shaft, and a ring shaped gear 29 that is rotated by the input gear 46. The rotation stop mechanism 50 stops the rotation of the frame 28 at the developing position. Also, the number of gear teeth in the ring shaped gear 29 is the number of gear teeth in the input gear 46 multiplied by the number of developers.

Abstract: An image forming device includes an image forming device body having an image forming unit in the interior thereof, and at least one paper tray attached to the image forming device on which paper is to be mounted. The paper tray includes a paper mounting unit having a paper mounting surface on which paper is to be mounted, and at least one movable auxiliary mounting unit. The auxiliary mounting unit is supported by the paper mounting unit, and includes an auxiliary mounting surface that is deployed from the paper mounting unit and which serves to extend the mounting surface. The brightnesses of the mounting surface and the auxiliary mounting surface of the paper tray are lower than the brightness of the paper to be mounted on each mounting surface, and the brightness of at least a portion of the auxiliary mounting surface is higher than the brightness of the mounting surface.

Abstract: The image forming unit 100 includes a photosensitive drum 11, a rotary developing device 30, and a rotation speed control device 70. Electrostatic latent images are formed on the surface of the photosensitive drum 11. The rotary developing device 30 includes a plurality of developing apparatuses 13 having a developing roller 14 disposed in opposition to the photosensitive drum 11, and a distance regulating collar 73 that regulates the distance between the photosensitive drum 11 and the developing roller 14. The rotation speed control device 70 includes a rotation speed control device 71 that controls the rotation speed of the rotary developing device 30 so that for a predetermined period of time until the developing apparatus 13 reaches the developing position the rotation speed of the photosensitive drum 11 and the movement speed in the circumferential direction of the distance regulating collar 73 are equal.

Abstract: An image forming apparatus includes a first sheet conveying passage that conveys a sheet through an image forming section. A sheet-discharging roller is on an outlet side of the first sheet conveying passage and can rotate in opposite directions. A second sheet conveying passage has an inlet connected to the first sheet conveying passage downstream from the image forming section and an outlet connected to the first sheet conveying passage upstream from the image forming section. A controller controls double-sided printing by causing the sheet-discharging roller to rotate forward to advance the sheet outside the sheet-discharging roller, and then to rotate in reverse to execute a switchback for transporting the sheet to the inlet side of the second sheet conveying passage and then to return the sheet to the upstream of the image forming section. An assisting mechanism adjusts a posture of the sheet to assist the switchback.

Abstract: An image forming device includes an image forming device body having an image forming unit in the interior thereof, and at least one paper tray attached to the image forming device on which paper is to be mounted. The paper tray includes a paper mounting unit having a paper mounting surface on which paper is to be mounted, and at least one movable auxiliary mounting unit. The auxiliary mounting unit is supported by the paper mounting unit, and includes an auxiliary mounting surface that is deployed from the paper mounting unit and which serves to extend the mounting surface. The brightnesses of the mounting surface and the auxiliary mounting surface of the paper tray are lower than the brightness of the paper to be mounted on each mounting surface, and the brightness of at least a portion of the auxiliary mounting surface is higher than the brightness of the mounting surface.

Abstract: An image forming device includes an image forming device body having an image forming unit in the interior thereof, and at least one paper tray attached to the image forming device on which paper is to be mounted. The paper tray includes a paper mounting unit having a paper mounting surface on which paper is to be mounted, and at least one movable auxiliary mounting unit. The auxiliary mounting unit is supported by the paper mounting unit, and includes an auxiliary mounting surface that is deployed from the paper mounting unit and which serves to extend the mounting surface. The brightnesses of the mounting surface and the auxiliary mounting surface of the paper tray are lower than the brightness of the paper to be mounted on each mounting surface, and the brightness of at least a portion of the auxiliary mounting surface is higher than the brightness of the mounting surface.

Abstract: The image forming unit 100 includes a photosensitive drum 11, a rotary developing device 30, and a rotation speed control device 70. Electrostatic latent images are formed on the surface of the photosensitive drum 11. The rotary developing device 30 includes a plurality of developing apparatuses 13 having a developing roller 14 disposed in opposition to the photosensitive drum 11, and a distance regulating collar 73 that regulates the distance between the photosensitive drum 11 and the developing roller 14. The rotation speed control device 70 includes a rotation speed control device 71 that controls the rotation speed of the rotary developing device 30 so that for a predetermined period of time until the developing apparatus 13 reaches the developing position the rotation speed of the photosensitive drum 11 and the movement speed in the circumferential direction of the distance regulating collar 73 are equal.

Abstract: A rotary developing device 30 is provided in an image forming device that is rotated by an input gear 46. The rotary developing device 30 has a plurality of developing units 13, a frame 28, and a rotation stop mechanism 50. Each of the plurality of developing units 13 house toner of one of the colors, and develops at a predetermined developing position. The frame 28 includes a support portion 36 that supports the plurality of developing units 13 and has a rotation shaft, and a ring shaped gear 29 that is rotated by the input gear 46. The rotation stop mechanism 50 stops the rotation of the frame 28 at the developing position. Also, the number of gear teeth in the ring shaped gear 29 is the number of gear teeth in the input gear 46 multiplied by the number of developers.

Abstract: A color printer 1 has a rotary type developing device 30 which rotated by an input gear 46 that receives power from a motor, and a plurality of developing units 13 supported on a frame 28. The plurality of developing units 13 accommodates toner of different colors therein. The frame 28 a first annular gear 29 being configured to be rotated by the input gear 46, and a second ring-shaped annular member 32 having a larger external diameter than the first annular gear 29. The second ring-shaped annular member 32 is disposed adjacent to and on the outer side of said first annular gear and on the same rotational axis.

Abstract: Through a coupling member 30, a drive-feed shaft 41a is fitted and, at the other end of the drive-feed shaft 41a, a drive-transmission gear 40a is fixed. By a compression spring 44, the coupling member 30 is loaded with a force that tends to move it in the direction indicated by arrow D, and is in a first position where the coupling member 30 coupling member 30 couples the drive-feed shaft 41a with a rotated member. When an arm member 33 is pulled up in the direction indicated by arrow E, a first rib 30a rides on a second rib 34 along a slanted surface 34a, and the coupling member 30 moves in the direction indicated by arrow D? against the force exerted by the compression spring 44, and is retracted into a second position where the coupling member 30 decouples the rotated member from the drive-feed shaft 41a.