Abstract: Methods and devices for moving media sheets through an image forming device. A sensor is positioned within an input area to determine a height of a media stack. When the media stack is full, a top-most sheet of the media stack is physically closer to the beginning point of the media path. When the media stack is depleted, the top-most sheet is positioned a further distance away from the beginning point. Movement of the media sheet is determined based on the height of the media stack. When the media stack is above a predetermined amount, the media sheet is moved according to a first algorithm. When the media stack is below the predetermined amount, the media sheet is moved according to a second algorithm.

Abstract: A stalled roll registration system and method includes a mechanism that allows for pivoting deskew action in a pre-registration nip in the form of a segmented pre-registration drive roll assembly mounted on a releasable low friction lateral translation carriage. Outer pre-registration idler nips are provided that open to allow a sheet to pivot and close for transport the sheet. The pre-registration idlers are engaged and the drive roll assembly remains locked in the lateral position for initial paper transport up to the stalled registration roll. After the sheet arrives at the stalled registration roll and starts to form a buckle for deskew, the outer pre-registration idlers and carriage are released. The body of the sheet is then free to pivot about the center drive nip and translate in the lateral direction to self align itself with the registration roll.

Abstract: A separation roller set comprises a shaft, a separation roller, a separation pad, an aligning roller, and an idle roller is provided in the present invention. The separation roller is fixed on the shaft with the separation pad leaning thereon. The separation roller is utilized to carry a sheet of paper moving through a gap between the separation roller and the separation pad. The aligning roller is located on the shaft with an idle roller leaning thereon. The leading edge of the sheet of paper leaving the gap is stopped and aligned by the aligning roller and the idle roller.

Abstract: An image forming apparatus includes a tray, a sheet conveying path through which sheets are conveyed, a sheet feeding unit including a sheet feed roller for feeding a first sheet to a sheet holding position, a sheet conveying unit having a conveyor roller that intermittently rotates and holds the sheets. The sheet conveying unit is upstream from a recording position, and downstream from the sheet feeding unit. The image forming apparatus also includes a recording unit, and a controller. The recording unit forms an image onto the first sheet while the conveyor roller is not rotating. The sheet feeding unit feeds a leading edge of a second sheet to the sheet conveying unit and maintains the leading edge of the second sheet colliding against the sheet conveying unit at the sheet holding position by rotating the sheet feed roller prior to completing image formation on the first sheet.

Abstract: A sheet handling apparatus includes a sheet stacker for stacking sheets; a separating device for separating and feeding the sheets stacked on the sheet stacker; and a register roller disposed adjacent to the separating device for correcting a skew of the sheet. An ultrasonic wave sensor composed of a wave sending sensor and a wave receiving sensor is arranged between the separating device and the register roller obliquely relative to a surface of the sheet. A judging device is electrically connected to the ultrasonic wave sensor for detecting a double feed of the sheets based upon an output signal from the wave receiving sensor at a predetermined time after the register roller starts rotating. A control device electrically connected to the judging device and the register roller controls the register roller to stop and rotate.

Abstract: An image forming apparatus is provided. The image forming apparatus is capable of suppressing occurrence of a problem caused by misalignment of the feeding speed at the time of delivery and receipt in the intermediate feeding roller with a simple configuration without increasing costs. The image forming apparatus includes a drive controller that controls the drive speed of an intermediate feeding roller that performs skew correction for the sheet, and a feeding speed information acquisition section that acquires information relating to the feeding speed of the sheet to be fed to the intermediate feeding roller. The drive controller drives the intermediate feeding roller at least three different speeds based on the information relating to the feeding speed acquired by the feeding speed information acquisition section.

Abstract: An improved apparatus and method for accumulating sheets having a horizontal transport deck. Inserts are fed from an insert feeder positioned above the deck. Driven accumulator nip rollers are positioned to receive accumulations of sheets transported on the horizontal deck, and they are also positioned close enough to the insert feeder to receive inserts fed from the insert feeder. A recessed accumulation deck is positioned immediately downstream of the accumulator nip rollers. When a first sheet rests in the recessed accumulation deck, a subsequent second sheet will be placed on top of the first sheet when it enters the recessed deck. The process is controlled whereby insert sheets are released by the insert feeder prior to arrival of an accumulation on the deck. The released insert is driven by the accumulator nip rollers onto the recessed accumulator deck. Then when the accumulation arrives, it is deposited on top of the insert resting there.

Abstract: A sheet feeding apparatus includes a sheet tray, a pickup roller, a feed roller, a driving motor to drive the feed roller via a feed clutch, and a reverse roller connected to a reverse shaft driven by the driving motor via a torque limiter. The feed clutch is turned OFF when a trailing edge of a sheet passes through a nip formed between the feed and reverse rollers so as to disconnect the driving motor in order to enable the feed roller to freely rotate. The rotation of the reverse shaft is transmitted to the reverse roller by the operation of the torque limiter so as to enable the reverse roller to rotate and return the next sheet nipped by the reverse and feed rollers in a counter sheet feeding direction.

Abstract: A sheet supplying device includes a stacker for placing sheets; a delivery device for separating and feeding the sheets on the stacker; a register device for temporarily holding a sheet; a sheet conveying guide for guiding the sheet from the register device to a processing position; a sheet sensor disposed between the delivery device and the register device for detecting the sheet; at least one driving device for driving the delivery device and the register device; a conveyance control device for controlling the driving device so that the delivery device and the register device form a loop of the sheet according to a signal from the sheet sensor and an overlap sensor disposed between the register device and the processing position for detecting overlapping of the sheet. An overlap determining device determines overlapping of the sheet according to signals from the sheet sensor and the overlap sensor.

Abstract: According to an embodiment, an idler roller has an insertion through-hole through which a rotation shaft is inserted. Collar-shaped stopper portions are formed on the rotation shaft and are located on both left and right sides of the idler roller when the rotation shaft is inserted and provided at a normal position. Coil springs are attached between the stopper portions and base surfaces of concave groove portions of the idler roller. The idler roller is held at the normal position by biasing force of both the coil springs when paper is not seized. When paper is seized, the idler roller is moved in a lateral direction by elastic restoring force caused by a torsion phenomenon occurring in the paper. The idler roller returns to the normal position due to biasing force of both the coil springs after the paper has passed through the idler roller.

Abstract: A guide member, which is constituted by an upper paper guide and a lower paper guide that form a paper transport path, is arranged between registration rollers and pre-registration rollers. At least one of the upper paper guide and the lower paper guide is supported swingably during printing operation.

Abstract: Positioning in the width direction of a sheet is performed by a skew correcting unit which is provided on a re-conveying path for reversing the sheet and conveying it again to an image forming unit and which has a reference surface that is come into contact with a side edge of the sheet and a plurality of diagonal feed units which obliquely convey the sheet so as to be come into contact with the reference surface. The pressures in nip portions of the other diagonal feed units excluding one of the plural diagonal feed units are reduced or cancelled by a reducing/cancelling unit according to a length in the sheet conveying direction of the sheet which is conveyed.

Abstract: A method for aligning print media on a feedpath includes the steps of: aligning a sheet of print media using a deskew mechanism; measuring the skew of the sheet after it has been aligned; and comparing the measured skew with a specified skew, and if the measured value is greater than the specified value, reversing the sheet through the deskew mechanism followed by repeating the aligning, measuring and comparing steps. An apparatus for implementing alignment of print media on a feedpath comprises a deskew mechanism and sensors positioned downstream on the feedpath from the deskew mechanism to provide data sufficient to calculate the skew of the sheet.

Abstract: A recording apparatus has a paper feeder wherein single sheets of paper can be set, a paper delivery device for transporting paper fed from the paper feeder to a recorder, and a control unit for controlling operation of the paper feeder and the paper delivery device. The control unit has a skew removal execution mode of only the first sheet of paper where the paper tip is bitten into a paper delivery roller forming a part of the paper delivery device and then the paper delivery roller is reversely rotated for ejecting the paper tip for the first sheet of paper at the start of recording and then forward rotating the paper delivery roller for delivering the sheet of paper whose skew is removed to the recorder and delivering the second and later sheets of paper to a record area without executing the skew removal.

Abstract: Sheet registration with improved sheet deskewing of print media sheets may be provided with an intermediately transversely pivotal baffle member overlying and engaging at least part of a buckled sheet being edge registered so that the effective buckle chamber size and sheet path length on one side of the sheet is automatically different from the other side of the sheet with said pivoting of said pivotal baffle member, to assist in the deskewing of the sheet as it is being partially buckled by the sheet registration system. The direction and amount of baffle pivoting may be self-pivoted by the extent of transverse buckle difference, or positively driven in response to a detected sheet skew.

Abstract: Systems and methods for deskewing a substrate with at least one of a first substrate supplying member and second substrate supplying member that supplies substrates to a chamber that receives the sheet supplied from both the first substrate supplying member and the second substrate supplying member.

Abstract: An image forming device capable of distinguishing the type of paper, and a driving controlling method thereof. The an image forming device includes a paper conveyance path disposed in a body of the image forming device, to guide an upside and an underside of the paper which is conveyed from a paper feeding apparatus to an image forming portion; a feeding roller disposed in the paper conveyance path, to convey the paper from the paper feeding apparatus to the image forming portion; and a paper type distinguishing sensor disposed in the paper conveyance path upstream with respect to the feeding roller, to distinguish the type of the paper and output a distinguishing signal. Accordingly, before the paper enters into the image forming portion, the distinguishing signal is output from the paper type distinguishing sensor as the feeding roller is rotated in a reverse direction to align a front end of the paper in parallel with the feeding roller.

Abstract: A sheet registration system in an arcuate sheet path of a compact printer with a sheet feeding system in which the lead edge of the sheet is partially arcuately buckled against a transversely extending registration gate in said sheet path (such as stalled or slower speed sheet feed roller nips, or retractable fingers) in which there is a transversely variable arcuate control baffle system in said sheet path upstream of the registration gate for accommodating skewed sheets in the sheet path and thereby providing improved alignment of the lead edge of the skewed sheets with the transversely extending registration gate. The illustrated transversely variable arcuate control baffle system is provided by a variably positionable split baffle system providing for a larger arcuate buckle for one side of a skewed sheet than the other side of the skewed sheet. This may be in proportion to a sensed initial skew of the sheet.

Abstract: A media conveying mechanism located in a media data recorder for conveying media mainly includes a driving motor to provide driving power needed. A first clutch to control the operation of a pickup roller. A second clutch to control rotation direction of an intermediate roller, a sensor to detect the conveying process of the media and control the operation of the second clutch. By deploying the two clutches, conveying quantity of the media in a unit time period can be effectively improved.

Abstract: A recording medium conveying device for an image forming apparatus of the present invention includes a conveying member for conveying a sheet or similar recording medium by nipping it. After the sheet being conveyed by the conveying member has abutted against a registering member, the registering member rotates in synchronism with the rotation of an image carrier carrying an image thereon for thereby conveying the recording medium toward an image transfer position. After the recording medium has slackened on abutting against the registering member, a nip canceling mechanism cancels the nip of the conveying member acting on the recording medium.

Abstract: A sheet feeding apparatus includes a stacking tray for stacking a sheet, a sheet feeding device for feeding the sheet, a register device for aligning a leading edge of the sheet fed by the sheet feeding device, a recognition device for recognizing a state that the sheets stacked on the stacking tray have different widths, and a setting device for setting a feeding distance according to a result of the recognition device. A control device controls the sheet feeding device to feed the sheet for the feeding distance.

Abstract: An image forming apparatus in that a sheet having an image formed on a first side thereof by an image forming portion is again transported to the image forming portion so that an image may be formed on an opposite or second side of the sheet, the image forming apparatus including a sheet feeding portion, a re-transport path, a pair of registration rollers provided upstream of the image forming portion, and a loop forming space provided upstream of the pair of registration rollers so as to form the loop, wherein an entrance to the loop forming space for the sheet having passed along the re-transport path is formed downstream of an entrance to the loop forming space for the sheet fed from the sheet feeding portion.

Abstract: A sheet supply apparatus includes a sheet storage device for stacking and storing sheets; a sheet pick-up device for drawing the sheets from the sheet storage means; a separating device having supply rollers for supplying the sheets drawn from the sheet pick-up means and separating members pressing the supply rollers; a pair of resister rollers for supplying the sheets to an aligning device after resister correction for aligning a transport direction of the sheets separated and transported by the separating device; and a frame for supporting each of the devices. The sheet supply apparatus is also provided with the first press separating device for the supply rollers and the separating members to be in a sheet nipping state or a sheet released state, and the second press separating device for the pair of the resister rollers to be in a sheet nipping state or a sheet released state.

Abstract: A method for aligning print media on a feedpath includes the steps of: aligning a sheet of print media using a deskew mechanism; measuring the skew of the sheet after it has been aligned; and comparing the measured skew with a specified skew, and if the measured value is greater than the specified value, reversing the sheet through the deskew mechanism followed by repeating the aligning, measuring and comparing steps. An apparatus for implementing alignment of print media on a feedpath comprises a deskew mechanism and sensors positioned downstream on the feedpath from the deskew mechanism to provide data sufficient to calculate the skew of the sheet.

Abstract: The invention is to provide a paper feeding apparatus and a driving method thereof for an office machine. The office machine includes a paper accommodating device and a paper processing apparatus. The paper accommodating device is for accommodating paper sheets to be processed by the paper processing apparatus. The paper feeding apparatus is for feeding the paper sheets accommodated by the paper accommodating device one by one to the paper processing apparatus. The paper feeding apparatus includes a pickup roller, a delivery roller, a pair of feeding rollers, a detection device, a transmission gear assembly, a drive motor and a controller. The detection device detects a leading edge and a trailing edge of the paper sheet delivered by the paper feeding apparatus. In particular, the paper feeding apparatus is a simple-configuration, light-weight and compact component and capable of feeding paper sheets accurately.

Abstract: The skew of a sheet of print media is precisely controlled by intentionally inducing print media deformation, so that cooperative mechanical and gravitational forces may be used to align the leading edge of the sheet. The sheet is driven into a nip region of deskew rollers in a manner that causes the print media to deform, lifting a movable member in a direction substantially perpendicular to the feedpath into the nip region. The movable member applies a return force that is generally equal along a widthwise surface region of the print media. As a result, there is a reduced likelihood that the print media will be skewed relative to the nip region. In some applications, the return force is adjustable.

Abstract: A sheet-position detection device has a stop unit for temporarily stopping a sheet conveyed along a sheet conveying path, and a sheet-position detector for detecting a position of the sheet in a direction transverse to a conveying direction of the sheet during the stop of the sheet. The stop unit includes a pair of rotating members for rotating in order to convey the sheet while grasping the sheet, and a sheet-position detector detects an edge of the sheet parallel to the sheet conveying direction.

Abstract: A paper sheet conveying apparatus and method for an image information processor in which a paper sheet with image information recorded thereon can be prevented from a skew carriage. The paper sheet conveying apparatus includes a driving motor which is controlled to be shifted from a forward revolution mode to a reverse revolution mode or vice versa. The paper conveying apparatus further includes a power cleaving means that selectively supplies the power to a first power transmitting system and to a second power transmitting system.

Abstract: A sheet conveyed by a conveying member is pressed against a registration roller pair in a stop state, thereby forming a loop in a loop formation space between the conveying member and the registration roller pair. A lower member which forms the lower surface of the loop formation space has a shape with which the sheet conveyed by the conveying member moves toward the registration roller pair along an upper member which forms the upper surface of the loop formation space in forming the loop. When the lower member is pressed by the sheet conveyed by the registration roller pair while attenuating the loop, the lower member moves downward.

Abstract: A sheet feeding apparatus includes a stacking tray for stacking a sheet, a sheet feeding device for feeding the sheet, a register device for aligning a leading edge of the sheet fed by the sheet feeding device, a recognition device for recognizing a state that the sheets stacked on the stacking tray have different widths, and a setting device for setting a feeding distance according to a result of the recognition device. A control device controls the sheet feeding device to feed the sheet for the feeding distance.

Abstract: A laser-beam printer includes a main unit and a plurality of tray units that can be stacked one upon the other under the main unit. Each of the tray units has a resist roller. The resist roller has a function of adjusting a deviation of a recording sheet fed from stacked sheets on a sheet supporting plate by a sheet feed roller and a function of feeding the recording sheet fed from a tray unit provided immediately below the main unit toward the main unit. A resist roller for adjusting a deviation of the recording medium is also provided upstream from an image forming unit in the main unit.

Abstract: A sheet conveying apparatus for an image information processor includes a driving apparatus having a sheet supply opening and a sheet discharge opening arranged above and below and in the same direction, and a registration roller, a delivery roller, a scan roller, and a delivery roller arranged in order along a sheet conveying path formed in an opening curve of a substantially C-shape. The driving apparatus drives the rollers in mutual operations with selective combinations according to a sheet conveying process, and includes a driving motor controlled to change driving modes in the forward and reverse directions, and a power switching device for selectively transferring a rotational force to first and second power transmission systems according to the driving modes of the driving motor, whereby changes in sheet conveying speeds are controlled to secure reliability in the skew-feed correction of a sheet when supplying a large capacity of sheets at a high speed, and to adjust image resolution by mode.

Abstract: A media feed mechanism includes a picking device, a first feedroller and a second feedroller. The picking device picks a sheet of media from a media source. The first feedroller moves the sheet of media along a feed media path. During a skew correction phase, the first feedroller rolls in a forward direction feeding the sheet of media forward and the second feedroller turns in a reverse direction preventing the sheet of media from progressing past a nip of the second feedroller. This results in skew correction. After skew correction is performed, the second feedroller turns in the forward direction advancing the sheet of media for printing.

Abstract: Apparatus for advancing media through a hardcopy device includes a cylindrical guide wheel having a first radius mounted on a shaft having an axis transverse to a media feed path axis. A guide surface is spaced apart from the guide wheel and defines a media feed path between the guide wheel and the guide surface. A drive wheel having an extended portion that is concentric with the guide wheel, and which has a greater radius than the first radius is fixed to the shaft. A pinch roller communicates with the media feed path.

Abstract: The present invention concerns a document processing and collating machine having a feeding path leading to at least one document conveying devices having one or more document accumulating bins for receiving a series of documents that are fed downstream in spaced apart collations with documents in shingled relationship. The document accumulator bins have an intermediate conveying and diverting apparatus which is momentarily engaged to cause a leading end of a shingled collation of documents to be diverted into a document accumulating bin where the documents are registered at their common leading end at a nip of a set of downstream conveying rollers that are stopped during the registration process.

Abstract: Before stopper members (25) of a skew correcting mechanism (10) are evacuated from a sheet conveyor path, sheet conveyor roller pairs (8) rotate a set angle in a direction opposite to the sheet feeding direction such that a sheet is separated from the stopper members (25). The sheet conveyor roller pairs (8) are arranged so that at least one of the rollers of each pair is independently pressed against the other with a force corresponding to the type of the sheet.

Abstract: A paper sheet conveying apparatus and method for an image information processor in which a paper sheet with image information recorded thereon can be prevented from a skew carriage. The paper sheet conveying apparatus includes a driving motor which is controlled to be shifted from a forward revolution mode to a reverse revolution mode or vice versa. The paper conveying apparatus further includes a power cleaving means that selectively supplies the power to a first power transmitting system and to a second power transmitting system.

Abstract: A recording medium conveying device for an image forming apparatus of the present invention includes a conveying member for conveying a sheet or similar recording medium by nipping it. After the sheet being conveyed by the conveying member has abutted against a registering member, the registering member rotates in synchronism with the rotation of an image carrier carrying an image thereon for thereby conveying the recording medium toward an image transfer position. After the recording medium has slackened on abutting against the registering member, a nip canceling mechanism cancels the nip of the conveying member acting on the recording medium.

Abstract: A sheet feeding apparatus has three sheet feeding units stacked vertically and is detachably mounted to an image forming apparatus. The upper most sheet feeding unit includes a tray for stacking and storing a sheet; a pick-up roller for feeding the sheet one at a time; a feed roller; a retard roller; a pair of register rollers; a curl forming portion for abutting against a leading edge of the sheet fed by these rollers in the sheet feeding direction to remove skew of the sheet by curling the sheet and for allowing the sheet to move further downstream; and a cylindrical cutter for punching a hole in the sheet. The sheet is transferred in a short distance and the sheet is fed one at a time.

Abstract: A recording-medium transport device includes a pair of pinch rollers arranged closer to a printing head than to a subordinate roller and pinching and transporting a belt and a sheet of paper toward the printing head. The pair of pinch rollers can pinch the sheet of paper together with the belt, while maintaining the belt flat. As such, an image of high quality can be formed, e.g., printed on the recording medium. Furthermore, the recording medium does not divert from a transporting path. Thus reliable image formation can be achieved.

Abstract: A sheet supply apparatus includes a sheet storage device for stacking and storing sheets; a sheet pick-up device for drawing the sheets from the sheet storage means; a separating device having supply rollers for supplying the sheets drawn from the sheet pick-up means and separating members pressing the supply rollers; a pair of resister rollers for supplying the sheets to an aligning device after resister correction for aligning a transport direction of the sheets separated and transported by the separating device; and a frame for supporting each of the devices. The sheet supply apparatus is also provided with the first press separating device for the supply rollers and the separating members to be in a sheet nipping state or a sheet released state, and the second press separating device for the pair of the resister rollers to be in a sheet nipping state or a sheet released state.

Abstract: A paper feed unit has a paper feed tray stacking sheets thereon, a primary paper feed roller and a secondary paper feed member, wherein an uppermost sheet among the sheets stacked on the paper feed tray is transferred toward the secondary paper feed member from the primary paper feed roller, a tip end of the sheet then contacts with the secondary paper feed member, and primary paper feed is then completed while the sheet is being bent. A counter rotation stop mechanism, which allows the primary paper feed roller to rotate in a paper feed direction but prevents the primary paper feed roller from rotating in a counter direction to the paper feed direction, and a rotation stop release mechanism, which releases a state in which the primary paper feed roller is prevented from rotating in the counter direction by the counter rotation stop mechanism, are also provided.

Abstract: The invention is to provide a paper feeding apparatus and a driving method thereof for an office machine. The office machine includes a paper accommodating device and a paper processing apparatus. The paper accommodating device is for accommodating paper sheets to be processed by the paper processing apparatus. The paper feeding apparatus is for feeding the paper sheets accommodated by the paper accommodating device one by one to the paper processing apparatus. The paper feeding apparatus includes a pickup roller, a delivery roller, a pair of feeding rollers, a detection device, a transmission gear assembly, a drive motor and a controller. The detection device detects a leading edge and a trailing edge of the paper sheet delivered by the paper feeding apparatus. In particular, the paper feeding apparatus is a simple-configuration, light-weight and compact component and capable of feeding paper sheets accurately.

Abstract: A registration roller 30 is preferably interposed between a first tangent line L1 passing through a handling portion between a first sheet feed roller 38 and a first handling member 42, and a second tangent line L2 passing through a handling portion between a second sheet feed roller 40 and a second handling member 44 (or the registration roller 30 may also be disposed so as to project out slightly from this range), and also the registration roller 30 may be preferably disposed downwardly of a horizontal line L3 passing through an upper end of the first sheet feed roller 38. In case where the first sheet feed roller 38, the second sheet feed roller 40 and the registration roller 30 are disposed so as to be as close as possible to one another, the height dimensions of a sheet feed apparatus 28 can be reduced to a minimum.

Abstract: A laser-beam printer includes a main unit and a plurality of tray units that can be stacked one upon the other under the main unit. Each of the tray units has a resist roller. The resist roller has a function of adjusting a deviation of a recording sheet fed from stacked sheets on a sheet supporting plate by a sheet feed roller and a function of feeding the recording sheet fed from a tray unit provided immediately below the main unit toward the main unit. A resist roller for adjusting a deviation of the recording medium is also provided upstream from an image forming unit in the main unit.

Abstract: The rotation of the second conveyance rollers located downstream from the first conveyance rollers, which are located downstream from the thermal fixing device of the image forming apparatus, is stopped for a prescribed period of time, or the speed of the second conveyance rollers is made slower than that of the first conveyance rollers. A loop is formed in the sheet through this difference in rotation speed, and the curling of the sheet caused through the thermal fixing is corrected. A torque limiter (or one-way clutch) is mounted at least in the drive path for either the first or second conveyance path. When a rigid sheet such as thick paper or low-moisture paper—for which curling is not likely—is conveyed, slipping occurs in the drive path due to the rigidity of the sheet itself, and the loop formation is automatically cancelled.

Abstract: An image forming apparatus includes: a sheet feeding member for feeding a recording material; an image recording member for recording an image on the recording material; a conveyance path connecting the sheet feeding member and the image recording member, along which the recording material is conveyed; a registration member which is provided in the conveyance path located at the upstream side of the image recording member in the conveyance direction for the recording material, and stops the leading edge of the recording material when being hit by the leading edge, and then, starts conveyance of the recording material; a loop forming member which is provided in the conveyance path located at the upstream side of the registration member in the conveyance direction for the recording material, and forms a loop on the recording material which is stopped by the registration member; a first driving source for driving the registration member; a second driving source for driving the loop forming member; and a drive co

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: A sheet feeding apparatus has a pair of feeding roller and separating roller an inter-shaft distance changing mechanism for the pair of rollers, and sheet detecting means, and a sheet fed is rammed against the surface on which the feeding roller and the separating roller overlap each other to thereby correct skew feeding, and the feeding roller and the separating roller are moved away from each other to thereby feed the sheet. When the passage of the fed sheet between the feeding roller and the separating roller is detected the feeding roller and the separating roller assume a state in which sheet feeding is impossible. By the above-described operation being performed for each sheet, the correction of skew feeding and the separation of a sheet are effected by the feeding roller and the separating roller.

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.