Abstract: An image forming apparatus includes an image forming portion, a tray rotatably provided on a side surface of a main assembly and including a stacking surface, a feeding portion; and a blowing fan mounted on the tray and generating air blown to a side end of a sheet in a sheet widthwise direction perpendicular to a feeding direction of the sheet by the feeding portion. The blowing fan is disposed on an opposite side to a side where the sheet is stacked on the stacking surface so that a position of at least a part of the blowing fan with respect to the sheet widthwise direction is overlapped with a position of the stacking surface with respect to the sheet widthwise direction.

Abstract: An image formation apparatus to form an image on a sheet having a width direction includes a separation and feed roller pair having a feed roller, a conveyance roller pair having a driving roller, and a pair of conveyance guides having inner and outer guides. A part of the inner guide overhangs toward an outer guide side from an external common tangent of the feed roller and the driving roller. Points of intersection with the feed roller on the external common tangent are designated as first intersection points and points of intersection with the driving roller on the external common tangent are designated as second intersection points. When ends of the feed and driving rollers serve as vertexes, a guide surface of the inner guide is linearly continuous in the width direction in an inner region on the guide surface of the inner guide formed by connecting the vertexes.

Abstract: An image formation apparatus to form an image on a sheet having a width direction includes a separation and feed roller pair having a feed roller, a conveyance roller pair having a driving roller, and a pair of conveyance guides having inner and outer guides. A part of the inner guide overhangs toward an outer guide side from an external common tangent of the feed roller and the driving roller. Points of intersection with the feed roller on the external common tangent are designated as first intersection points and points of intersection with the driving roller on the external common tangent are designated as second intersection points. When ends of the feed and driving rollers serve as vertexes, a guide surface of the inner guide is linearly continuous in the width direction in an inner region on the guide surface of the inner guide formed by connecting the vertexes.

Abstract: A sheet conveyance apparatus includes a shaft portion, a roller member, and a guide member. The roller member includes a hole portion with an opening through which the shaft portion is fitted with the hole portion. At least a part of the guide member is located upstream of an end of the shaft portion in an attaching direction of the roller member. A distance between rotation axes of the roller member and the shaft portion is smaller than a difference between a radius of the opening and a radius of the end of the shaft portion in a state where an outer circumferential surface of the roller member is in contact with the guide member at a position upstream of the end of the shaft portion in the attaching direction.

Abstract: A sheet conveyance apparatus includes a shaft portion, a roller member, and a guide member. The roller member includes a hole portion with an opening through which the shaft portion is fitted with the hole portion. At least a part of the guide member is located upstream of an end of the shaft portion in an attaching direction of the roller member. The end of the shaft portion is located inside the opening of the hole portion when viewed in the attaching direction in a state where an outer circumferential surface of the roller member is in contact with the guide member at a position upstream of the end of the shaft portion in the attaching direction.

Abstract: An image forming apparatus includes an image forming unit to form an image on a sheet, first and second rollers, a motor, a phase determiner, a controller, a current detector, and a discriminator. The motor drives the first roller which conveys the sheet. The second roller is downstream from the first roller. The phase determiner determines a rotation phase of a rotor of the motor. The controller controls a drive current flowing through a motor winding to reduce a deviation between a command phase representing a rotor target phase and the determined rotation phase. The current detector detects the drive current flowing through the winding. The discriminator determines a type of the sheet conveyed by the first roller based on a value of the drive current detected in a state in which the sheet is deflected while being conveyed by the first roller and not conveyed by the second roller.

Abstract: A sheet conveying apparatus includes a pair of first conveying rollers, a pair of second conveying rollers provided at a downstream of the pair of first conveying rollers in a conveying direction of a sheet, a loop being formed in the sheet when a head of the sheet conveyed by the pair of first conveying rollers butts against the pair of second conveying rollers, and a controller which executes a first control mode in which the sheet is conveyed by the pair of first conveying rollers and the pair of second conveying rollers without dissolving the loop formed in the sheet, or a second control mode in which the loop formed in the sheet is dissolved, and the sheet nipped by the pair of first conveying rollers and the pair of second conveying rollers is conveyed.

Abstract: An image forming apparatus includes an image forming unit to form an image on a sheet, first and second rollers, a motor, a phase determiner, a controller, a current detector, and a discriminator. The motor drives the first roller which conveys the sheet. The second roller is downstream from the first roller. The phase determiner determines a rotation phase of a rotor of the motor. The controller controls a drive current flowing through a motor winding to reduce a deviation between a command phase representing a rotor target phase and the determined rotation phase. The current detector detects the drive current flowing through the winding. The discriminator determines a type of the sheet conveyed by the first roller based on a value of the drive current detected in a state in which the sheet is deflected while being conveyed by the first roller and not conveyed by the second roller.

Abstract: When a sheet fed by a feed rotating member passes through a detection area of a leading edge detecting portion, the feed rotating member is moved to a retract position based on the detection. When the fed sheet does not pass through the detection area, the feed rotating member is moved to the retract position after a predetermined time elapses since the sheet starts to be fed by the feed rotating member.

Abstract: A sheet conveying apparatus includes a pair of first conveying rollers, a pair of second conveying rollers provided at a downstream of the pair of first conveying rollers in a conveying direction of a sheet, a loop being formed in the sheet when a head of the sheet conveyed by the pair of first conveying rollers butts against the pair of second conveying rollers, and a controller which executes a first control mode in which the sheet is conveyed by the pair of first conveying rollers and the pair of second conveying rollers without dissolving the loop formed in the sheet, or a second control mode in which the loop formed in the sheet is dissolved, and the sheet nipped by the pair of first conveying rollers and the pair of second conveying rollers is conveyed.

Abstract: A sheet feeder includes a sheet feeding unit configured to feed a sheet from a sheet storage case in a sheet feeding direction orthogonal to a loading direction in which the sheet storage case is loaded into an apparatus main body, and a conveying guide configured to guide the sheet fed by the sheet feeding unit. The conveying guide includes a first guide segment included in the apparatus main body and a second guide segment included in the sheet storage unit. The sheet feeder further includes an edge guide member disposed at an end of the first guide segment. The edge guide member has a guide surface that allows reaction force including a directional force component acting upward and a directional force component acting in a direction opposite to the sheet feeding direction to be generated when the sheet partly projecting from the sheet storage case abuts the guide surface.

Abstract: When a sheet fed by a feed rotating member passes through a detection area of a leading edge detecting portion, the feed rotating member is moved to a retract position based on the detection. When the fed sheet does not pass through the detection area, the feed rotating member is moved to the retract position after a predetermined time elapses since the sheet starts to be fed by the feed rotating member.

Abstract: A sheet feeder includes a sheet feeding unit configured to feed a sheet from a sheet storage case in a sheet feeding direction orthogonal to a loading direction in which the sheet storage case is loaded into an apparatus main body, and a conveying guide configured to guide the sheet fed by the sheet feeding unit. The conveying guide includes a first guide segment included in the apparatus main body and a second guide segment included in the sheet storage unit. The sheet feeder further includes an edge guide member disposed at an end of the first guide segment. The edge guide member has a guide surface that allows reaction force including a directional force component acting upward and a directional force component acting in a direction opposite to the sheet feeding direction to be generated when the sheet partly projecting from the sheet storage case abuts the guide surface.

Abstract: A sheet feeding portion is provided with a pair of separation rollers that include a feed roller which conveys the sent sheet and a retard roller which applies a rotation force to return the sheet in a direction opposite to a sheet feeding direction through a torque limiter in a state of being pressed against the feed roller. The sheet feeding portion further includes a rotation transmitting mechanism that transmits a rotation of the retard roller, at the time of sending the sheet to the sheet feeding direction, to the pickup roller and a changing mechanism that switches a retard pressure, which allows the retard roller to be pressed against the feed roller, according to a reaction force that is transmitted to the retard roller from the pickup roller.

Abstract: A sheet feeding apparatus and an image forming apparatus which can reliably feed even sheets having a non-uniform thickness to prevent excessive stacking. An auxiliary tray 1 is swingably provided on the upper surface of a tray 2 which is provided in a cassette body 3a to be lifted and lowered and stacks sheets thereon. When the sheets are stacked, a swing regulating portion 12 regulates the swing of the auxiliary tray 1 when the tray 2 is in a sheet stacking position and releases the regulation of the swing of the auxiliary tray 1 when the tray 2 is lifted.

Abstract: A sheet feeding portion is provided with a pair of separation rollers that include a feed roller which conveys the sent sheet and a retard roller which applies a rotation force to return the sheet in a direction opposite to a sheet feeding direction through a torque limiter in a state of being pressed against the feed roller. The sheet feeding portion further includes a rotation transmitting mechanism that transmits a rotation of the retard roller, at the time of sending the sheet to the sheet feeding direction, to the pickup roller and a changing mechanism that switches a retard pressure, which allows the retard roller to be pressed against the feed roller, according to a reaction force that is transmitted to the retard roller from the pickup roller.

Abstract: A sheet feeding apparatus and an image forming apparatus which can reliably feed even sheets having a non-uniform thickness to prevent excessive stacking. An auxiliary tray 1 is swingably provided on the upper surface of a tray 2 which is provided in a cassette body 3a to be lifted and lowered and stacks sheets thereon. When the sheets are stacked, a swing regulating portion 12 regulates the swing of the auxiliary tray 1 when the tray 2 is in a sheet stacking position and releases the regulation of the swing of the auxiliary tray 1 when the tray 2 is lifted.

Abstract: An image forming apparatus has a vibration generating source, a holding member that holds the vibration generating source and a sealing member arranged between them. An elastic damping member is inserted in a through-hold formed in the holding member and is brought into pressure contact with the vibration generating source, the damping member having a retaining portion which is retained to a surface of the holding member on the side opposite to a holding surface of the vibration generating source and a main body portion that has a diameter smaller than a diameter of the through-hole so that it is inserted into the through-hole without contacting the through-hole and brought into pressure contact with the vibration generating source. There is also a fixing portion that integrally fixes the holding member and the vibration generating source through the damping member.

Abstract: A sheet conveyance device has a sheet conveyance path formed by a guide member having a curved surface which is curved in a sheet conveyance direction, and a flexible sheet scanner is provided along the curved surface of the guide member, the flexible sheet scanner has an optical sensor layer in which photoelectric conversion devices formed by combinations of organic transistors and organic photodiodes are continuously arranged in a matrix shape.

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).