Abstract: A sheet transport device is provided with a sheet inverting mechanism for retracting a sheet transported along a main transport route into a switchback route to invert the sheet transport direction and returning the sheet into the main transport route to turn the side of the sheet. The sheet transport device has a pair of sheet guides adapted in contact with respective opposite ends of the sheet set on a sheet setting portion to prevent a skew transport of the sheet. The sheet temporarily brought onto the sheet setting portion during a switchback operation from the switchback route is guided between of the sheet guides on the sheet setting portion. During the temporal appearance on the sheet setting portion, the opposite ends of the sheet are aligned by the respective sheet guides. Thereby, securely prevented is an occurrence of a skew transport state of the sheet during the switchback operation.

Abstract: In a paper transport device, a first roller serving as a separation roller is situated underneath a second roller serving as a document feed roller, together forming a roller pair. A rotary shaft of the separation roller is biased upward toward the document feed roller by means of an elastic element. One end of the rotary shaft is connected to a drive shaft via a coupler while a connecting bar is joined to the other end of the rotary shaft obliquely from above. An extreme end of the connecting bar opposite to the rotary shaft is attached to a support plate fixed to a main body of the paper transport device in such a way that the connecting bar can swing about pivot pin fixed to the support plate. In the paper transport device thus constructed, one end of the rotary shaft fitted to the coupler acts as a point of support, allowing the other end of the rotary shaft to move downward overwhelming an upward-lifting force of the elastic element when forced downward by the connecting bar.

Abstract: A document separating mechanism for an automatic document feeder for separating and feeding the bottommost document of documents laid on document bearing means. A separating roller mechanism has a plurality of rollers provided at spaced locations in an axial direction, and a separating belt mechanism is disposed opposite and above the separating roller mechanism. The separating belt mechanism is composed of a driving roller and a driven roller disposed in parallel at spaced locations, a wide separating belt looped over the driving roller and the driven roller and pressed against the separating roller, and a tension imparting mechanism for exerting tension on the separating belt.

Abstract: A sheet transport device is provided with a sheet inverting mechanism for performing a switchback operation in which a sheet transported along a main transport route enters a switchback route, and the sheet transport direction is inverted in the switchback route to return the sheet to the main transport route so as to turn the side of the sheet. A registration roller pair is disposed near the junction between the main transport route and the switchback route. The sheet inverting mechanism is operated in such a manner that the sheet transport is temporarily suspended until a skew correctable portion that enables correction of a skew transport state of the sheet is formed at a lead end of the sheet in the exiting direction from the switchback route after the lead end of the sheet comes into contact with the registration roller pair. Thus, the skew transport state of the sheet which is liable to occur during the switchback operation is corrected.

Abstract: A conveying belt mechanism for an automatic document feeder, for conveying a document placed on a document bearing plate to a document exposure position on a transparent platen. The conveying belt mechanism includes a driving roller and a driven roller disposed above the transparent platen, with a predetermined spacing provided between the two rollers in a document feeding direction, an endless conveying belt looped over the driving roller and the driven roller, pressing rollers disposed between the driving roller and the driven roller for pressing the endless conveying belt against the transparent platen, and belt guides mounted at both ends of the driven roller.

Abstract: An automatic document feeder for sending a document from a document setting position on a document bearing plate to a document feeding path and returning the document onto the document bearing plate after feeding of the document along the document feeding path. A document mover includes a moving plate for moving the document that has been returned to the document bearing plate to the document setting position. A document presser presses the document that has been moved by the document mover to the document setting position. A controller controls the operation of the document presser and the document mover. The controller operates the moving plate of the document mover to move the document that has been returned to the document bearing plate to the document setting position, then operates the document presser to press the document that has been moved to the document setting position, and causes the moving plate of the document mover to recede, while maintaining the document in a pressed state.

Abstract: An automatic document feeder includes first and second registration rollers for abutting the leading end of an original conveyed along a conveying path against their contact positions. The first registration roller is included in a plurality of reversing rollers arranged apart from each other along an axis of a supporting shaft of each of the reversing rollers. The reversing roller turn over the original along a reversing path that bypasses a part of the conveying path. There is provided a reversal guiding member arranged so as to cover a region between the adjacent reversing rollers. The reversal guiding member has guide surfaces curved along the peripheral surfaces of the reversing rollers as viewed along the axis of the supporting shaft. The reversal of the original is guided along the reversing path by the guide surfaces.

Abstract: An automatic document feeder of a type having a document inverting mechanism beside a document sending-in path is disclosed which, when a document located at a document exposure position is to be inverted, operates a conveying belt mechanism in a predetermined direction to convey the document by a predetermined amount in a direction away from a document positioning member, then brings a document positioning member to a retreat position, and then operates the conveying belt mechanism in a direction opposite to the predetermined direction to convey the document to the document inverting mechanism.

Abstract: An automatic document feeder conveys an original along a conveying path to an original reading section in an image processor. First and second registration rollers for abutting the conveyed original against their contact portions, and a guide plate for guiding the conveyance of the original to the registration rollers are arranged in the conveying path. The first registration roller includes a plurality of reversing rollers made of rubber for reversing the original along a reversing path, and the reversing rollers are arranged a predetermined distance away from each other along an axis of their supporting shaft. A side edge in the direction of conveyance of the guide plate is in such a comb shape that projections and non-projections are alternatively formed. Each of the projections is opposite to a region between the adjacent reversing rollers, and extends toward the downstream side of the contact portions in the direction of conveyance.

Abstract: A document fed from a document tray to a first transport path is guided to a document inverting unit to invert a transport direction of the document. Subsequently, the document is transported to an image reader unit along a second transport path for image data reading on the opposite side of the document opposite to a side facing upward when set on the document tray. Then, the document is guided to the document inverting unit again via a fourth transport path intersecting a third transport path at a first intersecting point to invert the transport direction of the document again. Thereafter, the document is transported to the image reading unit again via the second transport path for image data reading on the one side of the document. The document is discharged onto a discharge tray via the third transport path with the one side facing downward.

Abstract: A recycle document feeder according to the present invention includes a pair of document width regulating guides (9a, 9b) for guiding opposite edges of document originals (D) fed back onto a document placing plate (8) for alignment thereof with respect to the width thereof. With this construction, if the document width regulating guides (9a, 9b) each had a small length (A) as measured along a document transportation direction, the document originals (D) fed back onto the document placing plate (8) could not properly be aligned by the document width regulating guides (9a, 9b) thereby to be randomly stacked on the skew with respect to the document transportation direction.

Abstract: A document feeder which includes a separator mechanism having a first separator member and a second separator member for separating and feeding document originals one by one into a document transportation path. The first separator member is provided in a main body, and the second separator member is provided in a cover which covers a portion of the main body and is adapted to be pivotally opened. With the cover being closed, the second separator member is positioned with respect to the first separator member by a positioning mechanism.

Abstract: A document feeder which has a document transportation path curved with a curvature radius such that a document original is reversed and fed therethrough to a document setting surface. The document feeder further includes a pair of rollers respectively disposed inside and outside of the curvature of the document transportation path in an opposed relation and adapted to hold the document original therebetween for guiding the document original to the document setting surface. The rollers abut against each other in a position upstream of the vertex of the curvature of the document transportation path with respect to a document transportation direction.

Abstract: A recycle document feeder according to the present invention includes a cover (251) covering a document discharge portion (30). The cover (251) is openably supported by a pivot shaft (256) between a pair of frames (255). A feed-back path (32) for guiding a document original onto a document placing plate is defined by a pair of guide members (257, 258) provided in an opposed relation. The upper guide member (258) is attached to the interior face of the cover (251). A switch claw (253) for switching the document traveling direction is attached to the pivot shaft (256) which supports the cover (251). Thus, there is no need for additionally providing a shaft for supporting the switch claw (253), thereby simplifying the construction of the document discharge portion (30).

Abstract: This invention relates to a document transport device for use in an image forming apparatus. The document transport device has a first belt roller disposed above a document positioning member. A second belt roller is disposed away from the first belt roller in the document transport direction. An endless belt is wound around the first and second belt rollers. Plural presser rollers are arranged on a specified position between the first and second belt rollers to press the belt against a contact glass. The document transport device has a tension roller between the first belt roller and the presser roller closest thereto to apply a tension force to the belt so as to set the belt at the lowermost position of the tension roller below a common tangential line to the circumferences of the first belt roller and the presser roller and apart from the contact glass.

Abstract: A recycle document feeder includes a partitioning unit (17) and action plates (19, 20). The partitioning unit (17) includes a partitioning bar (18). When the partitioning bar (18) is lowered, the leading edges of discharged document originals are stopped by the partitioning bar (18). The action plates (19, 20) guide the discharged document originals toward an upper side of the trailing edges of document originals yet to be fed, and push the trailing edges of the discharged document originals to transport the document originals for re-feeding thereof. The partitioning unit (17) and the action plates (19, 20) are driven by a common motor (47). Further, a partitioning unit driving mechanism (110) and an action plate driving mechanism (111) are provided for driving the partitioning unit (17) and the action plates (19, 20), respectively.

Abstract: A document feeder having a cover covering a portion of a main body and adapted to be pivotally opened, and a pair of document transportation rollers provided in an abutting relation in the midst of a document transportation path for transportation of a document original. A document guiding member for guiding the document original to an abutment position of the pair of rollers is attached to the cover.

Abstract: In an automatic document feeder, an original tray has an original platen on its upper surface. Originals put on the original platen are fed along a conveying path by conveying rollers and conveyance auxiliary rollers. The originals fed are separated one at a time by separating belts and separating rollers which are arranged above and below a conveying path. When a conveyance guide plate constituting a part of the original platen is removed upward, the separating rollers, the conveying rollers, and the conveyance auxiliary rollers and a portion for supporting the rollers are exposed upward, so that maintenance such as replacement of components such as the separating rollers, the conveying rollers and the conveyance auxiliary rollers can be performed.

Abstract: An image forming apparatus transfers a toner image formed on a photoconductive member onto transfer paper by passing the photoconductive member consecutively beside a main charger, exposure unit, developer unit, pre-transfer charger, transfer charger, and charge remover. During image formation under conditions with temperature or humidity lower than a predetermined level, the pre-transfer charger is deactivated.