Conveyance apparatus

A conveyance apparatus according to the disclosure includes a conveyance unit that conveys a sheet, a flapper movable between a first position and a second position, a flapper moving unit that moves the flapper to the first position when power is supplied, a door to open a predetermined conveyance path and a second conveyance path, a detection unit that detects an occurrence of an abnormal state relating to the conveyance apparatus, and a control unit that, in a case where the detection unit detects the occurrence of the abnormal state while a sheet is conveyed to the first conveyance path by the conveyance unit and the flapper is in the first position, stops a sheet conveyance operation of the conveyance unit and inhibits the flapper from moving to the second position by continuing to supply power to the flapper moving unit.

BACKGROUND OF THE INVENTION

Field of the Invention

The disclosure relates to control for switching a flapper in a conveyance apparatus that conveys sheets.

Description of the Related Art

A conveyance apparatus that sorts sheets to a plurality of sheet discharge bins is known as an example of a sheet discharge option apparatus which is used by being connected to an image forming apparatus. Such a conveyance apparatus has a flapper in a place where a conveyance path branches into a plurality of paths. The conveyance apparatus changes a conveyance destination of a sheet by switching a position of the flapper.

Japanese Patent Application Laid-Open No. 2011-241043 discusses a configuration in which a conveyance destination of a sheet received from an image forming apparatus is switched by a flapper, and a sheet discharge option apparatus that folds the conveyed sheets in half and book-binds them. The sheet discharge option apparatus is provided with a press unit that folds a sheet. The press unit is a pair of rollers that moves while nipping a folded sheet and applying pressure to it. The press unit moves along the width direction (direction perpendicular to the conveyance direction of sheets) of sheets.

According to Japanese Patent Application Laid-Open No. 2011-241043, in a case where a sheet jam (paper clogging) occurs during bookbinding processing, the press unit is moved to its home position. Then, the sheet jam is notified. The home position is a position outside the conveyance path in the width direction of sheets. The press unit in the home position does not hinder removal of jammed paper when a user removes the jammed paper remaining inside the apparatus. This reduces burden of the user when a sheet jam is cleared.

Many of the conventional conveyance apparatuses switch a position of a flapper by operating a solenoid. The flapper moves to a first position when the solenoid is turned on and moves to a second position due to influence of an elastic member, such as a spring, when the solenoid is turned off. When the flapper is in the first position, a sheet is conveyed to a first conveyance path and discharged to a first sheet discharge bin. When the flapper is in the second position, a sheet is conveyed to a second conveyance path and discharged to a second sheet discharge bin. The flapper moved to the second position closes the first conveyance path to prevent a sheet from being conveyed to the first conveyance path.

The conventional conveyance apparatuses are configured such that power supply to the solenoid is stopped when a sheet jam occurs while a sheet is conveyed to the first sheet discharge bin, to save power consumption. When the solenoid is turned off, the flapper moves from the first position to the second position. This movement may cause the flapper to trap a sheet against the first conveyance path. In such a case, the flapper becomes an obstacle when jammed paper is removed.

The above-described issue also arises in a configuration in which the position of the flapper is switched by an actuator other than the solenoid, for example, a stepping motor. This is because if power supply to the stepping motor is stopped, the force retaining the flapper in the first position is lost and the flapper may move to the second position where the flapper traps a sheet under the influence of gravity or the like. A similar issue also arises when, in addition to the case of occurrence of a sheet jam, a sheet conveyance operation is forcibly stopped after a failure of the conveyance apparatus, such as door opening of the apparatus occurs.

In the Japanese Patent Application Laid-Open No. 2011-241043, the flapper is utilized for the configuration of switching the conveyance destination of sheets and the press unit is discussed for reducing burden of the user when a sheet jam is cleared. However, the flapper is not discussed for reducing burden of the user when a sheet jam is cleared.

SUMMARY OF THE INVENTION

The disclosure is directed to a conveyance apparatus in which a flapper that switches a conveyance direction of a sheet is inhibited from becoming an obstacle to a user to improve user usability when a sheet remaining inside the apparatus is removed.

According to an aspect of the disclosure, a conveyance apparatus includes a conveyance unit configured to convey a sheet along a predetermined conveyance path, a flapper configured to be movable between a first position and a second position, the flapper in the first position guiding a sheet conveyed by the conveyance unit from the predetermined conveyance path to a first conveyance path branched from the predetermined conveyance path, the flapper in the second position guiding a sheet conveyed by the conveyance unit from the predetermined conveyance path to a second conveyance path branched from the predetermined conveyance path, a flapper moving unit configured to move the flapper to the first position when power is supplied to the flapper moving unit, wherein when power supply to the flapper moving unit is stopped, the flapper moves to the second position, a door configured to open the predetermined conveyance path and the second conveyance path, a detection unit configured to detect an occurrence of an abnormal state relating to the conveyance apparatus, and a control unit configured to, in a case where the detection unit detects the occurrence of the abnormal state while a sheet is conveyed to the first conveyance path by the conveyance unit and the flapper is in the first position, stop a sheet conveyance operation of the conveyance unit and inhibit the flapper from moving to the second position by continuing to supply power to the flapper moving unit.

Further features and aspects of the disclosure will become apparent from the following description of various example embodiments with reference to the attached drawings.

DESCRIPTION OF THE EMBODIMENTS

FIG. 1is a view illustrating a schematic structure of a conveyance apparatus according to a first example embodiment of the disclosure. As an example of the conveyance apparatus according to the present example embodiment, the schematic structure includes a sheet discharge option apparatus which is used by being connected to an image forming apparatus. The schematic structure also includes a laser beam printer as an example of the image forming apparatus.

InFIG. 1, a laser beam printer100(hereinafter referred to as the printer100) includes an image forming unit101, a sheet feeding unit102that feeds a sheet S to the image forming unit101, a fixing unit103that fixes an image formed on the sheet S, and a sheet discharge unit104. The sheet S is recording paper (recording material) on which an image is formed. The printer100is provided with a sheet discharge option apparatus200that performs post-processing when needed on the sheet S on which an image has been formed. The sheet discharge option apparatus200is detachably attached on the upper side of the printer100.

The image forming unit101includes a photosensitive drum111that rotates clockwise inFIG. 1, a charging roller112that charges the surface of the photosensitive drum111, and an exposure apparatus113that forms an electrostatic latent image by irradiating the photosensitive drum111with light L. The image forming unit101further includes a developing roller114that forms a toner image by putting toner on an electrostatic latent image formed on the photosensitive drum111and a transfer roller115that transfers a toner image formed on the photosensitive drum111to the sheet S fed by the sheet feeding unit102. The image forming unit101forms a toner image on the sheet S by image forming processing as described above. The fixing unit103includes a fixing roller116, a pressure roller117in contact with the fixing roller116from below, and a fixing/discharge roller118. The fixing roller116and the pressure roller117nip the sheet S to fix a toner image transferred to the sheet S on the sheet S by heat and pressure.

The sheet feeding unit102includes a cassette105on which a plurality of sheets S is stacked and a pickup roller106that feeds the sheet S stacked on the cassette105. The sheet feeding unit102further includes a sheet feeding roller107that feeds the sheet S fed by the pickup roller106to a conveyance path109. Furthermore, the sheet feeding unit102includes a top sensor129that detects the sheet S having passed through the conveyance path109and a registration roller110that conveys the sheet S to the image forming unit101. According to the timing when the sheet S is detected by the top sensor129, the formation of a toner image on the photosensitive drum111is started. Then, the sheet S is conveyed by the registration roller110to a transfer nip portion formed by the photosensitive drum111and the transfer roller115so that the sheet S and the toner image on the photosensitive drum111are synchronized with each other.

The sheet discharge unit104includes a flapper120, a conveyance roller119, a sheet discharge roller123, a sheet discharge tray124, and a full-state detection lever125. The flapper120guides the sheet S to which an image has been fixed by the fixing unit103to the sheet discharge tray124or the sheet discharge option apparatus200. The flapper120moves to a position indicated by a solid line inFIG. 1to guide the sheet S to the sheet discharge tray124, i.e., to a conveyance path128. The flapper120moves to a position indicated by a broken line inFIG. 1to guide the sheet S to the sheet discharge option apparatus200, i.e., to a conveyance path122. The flapper120is configured to be movable by an actuator (not illustrated). The sheet discharge tray124is provided on the top surface of the printer100and the sheet S conveyed by the conveyance roller119and the sheet discharge roller123is stacked thereon. When the full-state detection lever125detects a full state of the discharged sheets S, the printer100does not discharge the sheet S to the sheet discharge tray124until the sheets S on the sheet discharge tray124are removed.

Next, the configuration of the sheet discharge option apparatus200will be described with reference toFIG. 1. The sheet discharge option apparatus200according to the present example embodiment can sort and allocate the sheets S received from the printer100to a plurality of sheet discharge bins. The sheet discharge option apparatus200according to the present example embodiment can perform various types of post-processing, such as an alignment process and a staple process, on the sheet S.

The sheet S from the printer100is received and conveyed by an inlet roller pair201. The presence or absence of the sheet S is detected by an inlet sensor216(sheet detection unit) on a conveyance path219(predetermined conveyance path). The conveyance path219is connected to the conveyance path122of the printer100. A flapper202is provided in a place where the conveyance path219branches to a conveyance path212(first conveyance path) and a conveyance path204(second conveyance path) and guides the sheet S conveyed by the inlet roller pair201to the conveyance path212or the conveyance path204. The flapper202moves to the position (first position) indicated by the solid line illustrated inFIG. 1to guide the sheet S to the conveyance path212. The flapper202moves to the position (second position) indicated by the broken line inFIG. 1to guide the sheet S tot the conveyance path204.

The operation of the flapper202will be described in detail with reference toFIG. 2. In the present example embodiment, the position of the flapper202is switched by operating a solenoid220.FIG. 2Aillustrates a state in which the solenoid220is on. The solenoid220turns on by power supply and operates, and then, moves the flapper202to the position illustrated inFIG. 2Aagainst an elastic force of a spring221(elastic member).FIG. 2Billustrates a state in which the solenoid220is off. When power supply to the solenoid220is stopped, the flapper202moves to the position illustrated inFIG. 2Bdue to the elastic force of the spring221. The solenoid220and the spring221are together defined as a flapper moving unit.

The configuration of the sheet discharge option apparatus200will be described with reference toFIG. 1. When the sheet S is guided in a direction of the conveyance path204, the sheet S is conveyed by a conveyance roller203and a conveyance roller205. The presence or absence of the sheet S is detected by a conveyance sensor217(sheet detection unit) on the conveyance path204. In the downstream of the conveyance roller205in a conveyance direction of the sheet S, the sheet discharge option apparatus200includes an intermediate stack tray209that temporarily stores the sheet S. In the further downstream, the sheet discharge option apparatus200includes a jogger208that supports both ends in the width direction of the sheet S and aligns the position of the sheet S. The width direction of the sheet S is a direction parallel to the stacking face of the intermediate stack tray209and perpendicular to the conveyance direction of the sheet S. The jogger208includes, as illustrated in a perspective view ofFIG. 3, a first aligning member208aand a second aligning member208band is reciprocally moved by an aligning motor225in the width direction indicated by an arrow illustrated inFIG. 3to align the position of the sheet S in the width direction. The sheet S conveyed by the conveyance roller205is stacked in a manner extending over the jogger208and the intermediate stack tray209.

Above the intermediate stack tray209, an aligning paddle206and a sheet discharge roller207are provided. The sheet discharge roller207is rotated by an actuator (not illustrated) and is able to come into contact with or separate from the sheet S stacked on the intermediate stack tray209. A stapler210binds the ends of the sheets S stacked on the intermediate stack tray209and aligned by the jogger208. Below the jogger208in the vertical direction, a sheet discharge tray211is provided. When the sheet discharge roller207comes into contact with the sheet S stacked on the intermediate stack tray209and rotates, and then the jogger208moves to a retreating position (details thereof will be described below), the sheet S stacked on the intermediate stack tray209is discharged to the sheet discharge tray211.

A staple process of the sheet discharge option apparatus200will be described in detail below. When the staple process is performed, the flapper202moves to the position indicated by the broken line illustrated inFIG. 1to guide the sheet S to the conveyance path204. The sheet S guided to the conveyance path204is conveyed to the intermediate stack tray209by the conveyance roller205. In this process, the sheet discharge roller207is in a position separated from the sheet S which is to be stacked on the intermediate stack tray209. Before the sheet S is conveyed to the intermediate stack tray209by the conveyance roller205, the jogger208moves to a position where the jogger208can receive the sheet S. This state is illustrated inFIG. 4A.FIG. 4Ais a diagram illustrating the jogger208viewed from above in the vertical direction. The position where the jogger208can receive the sheet S is a state in which an interval between the first aligning member208aand the second aligning member208bis A. The interval A can be any interval which is longer than the length in the width direction of the sheet S and also is sufficient for the tip of the sheet S not to collide against the first and second aligning members208aand208bwhen the sheet S is conveyed by the conveyance roller205. The first aligning member208aand the second aligning member208bare operated by the aligning motor225in a linked manner.

The sheet S stacked in a manner extending over the intermediate stack tray209and the jogger208is supported on both ends of the sheet S in the width direction by the jogger208. More specifically, the first aligning member208acomes into contact with one end in the width direction of the sheet S and the second aligning member208bcomes into contact with the other end in the width direction of the sheet S. Then, the jogger208moves along the width direction of the sheet S to align the position of the sheet S in the width direction. This state is illustrated inFIG. 4B. The position where the sheet S is aligned by the jogger208is a state in which the interval between the first aligning member208aand the second aligning member208bis B. The interval B is an interval shorter than the interval A. The interval B has a length same as the length in the width direction of the sheet S or a length longer than the length in the width direction of the sheet S by some margin.

In the present example embodiment, the second aligning member208bis stopped at a reference position of alignment by a mechanical stopper (not illustrated) and only the first aligning member208amoves in the width direction. In other words, the sheet S is aligned by being bumped against the second aligning member208b.

After completion of the position alignment of the sheet S in the width direction by the jogger208, the position in the conveyance direction is aligned by the aligning paddle206. The aligning paddle206moves the sheet S stacked on the intermediate stack tray209to the side on which the stapler210is arranged and aligns the sheet S by bumping an edge of the sheet S against the stapler210. This completes the alignment process when a sheet S is conveyed to the intermediate stack tray209. If the job includes two sheets S or more on which the staple process is performed, the conveyance roller205conveys a subsequent sheet S to the intermediate stack tray209. Then, the above alignment process is repeated.

When a plurality of sheets S on which a staple process is performed is stacked on the intermediate stack tray209and the alignment process is performed by the jogger208and the aligning paddle206, the stapler210performs the staple process on the plurality of sheets S. Then, the sheet discharge roller207moves to a position where the sheet discharge roller207is in contact with the sheet S stacked on the intermediate stack tray209and discharges a bundle of sheets S on which the staple process has been performed to the sheet discharge tray211. In this process, the jogger208moves to the retreating position. This state is illustrated inFIG. 4C. The retreating position of the jogger208is a state in which the interval between the first aligning member208aand the second aligning member208bis C. The interval C is wider than the interval A. The interval C can be any interval at which the first and second aligning members208aand208bdo not come into contact with the sheet S. The target on which a staple process is performed may be a single sheet S.

The configuration of the sheet discharge option apparatus200will be further described with reference toFIG. 1. When the sheet S is guided in the direction of the conveyance path212, the sheet S is discharged to a sheet discharge tray215by a sheet discharge roller213. The presence or absence of the sheet S is detected by a conveyance sensor218(sheet detection unit) on the conveyance path212. When a full state of the sheets S discharged to the sheet discharge tray215is detected by a full-state detection lever214, the sheet discharge option apparatus200does not discharge the sheet S to the sheet discharge tray215until the sheets S on the sheet discharge tray215are removed. As described above, the sheet discharge option apparatus200includes a plurality of sheet discharge bins, i.e., the sheet discharge tray211and the sheet discharge tray215, and can sort and allocate sheets S to different trays.

The sheet discharge option apparatus200is also provided with a door222to release the inside of the apparatus. The user can open the door222and remove a sheet S remaining inside the sheet discharge option apparatus200.

FIG. 5is a control block diagram of the printer100and the sheet discharge option apparatus200in the present example embodiment. The printer100includes a controller300and the sheet discharge option apparatus200includes a control unit301(central processing unit (CPU)). The controller300and the control unit301are connected via a communication line. The control unit301of the sheet discharge option apparatus200includes a failure detection unit302and a sheet position determination unit303.

The controller300receives information about a print job by performing communication with external devices (not illustrated), such as computers, and sends the received information to the control unit301. The information about a print job is information indicating a conveyance destination of a sheet S, i.e., whether to send a sheet S to the sheet discharge tray211or the sheet discharge tray215. Based on the information, the control unit301controls the solenoid220to switch the position of the flapper202.

The inlet sensor216, the conveyance sensor217, and the conveyance sensor218are connected to the control unit301. The failure detection unit302of the control unit301is notified of detection results by these sensors. Further, a door open sensor223(door detection unit) that detects opening of the door222is connected to the control unit301. Based on detection results by these sensors, the failure detection unit302detects an occurrence of an abnormal state regarding the sheet discharge option apparatus200. The abnormal state regarding the sheet discharge option apparatus200is, for example, a state in which a sheet S is jammed (paper clogging) or a state in which the door222is open when the door222should be closed.

The failure detection unit302can detect a state in which a sheet S is jammed, based on various sensors, such as the inlet sensor216, the conveyance sensor217, and the conveyance sensor218. More specifically, if the various sensors do not detect a sheet even after a first predetermined time passes, the failure detection unit302determines that a delay jam of a sheet S has occurred somewhere before the sheet S reaches the various sensors. If a sheet S is detected by a sensor and the detection state of the sensor does not change even after a second predetermined time passes, the failure detection unit302determines that a retaining jam of a sheet S has occurred on the sensor. If the door open sensor223detects opening of the door222when the door222should be in a closed state while the sheet discharge option apparatus200conveys a sheet S, the failure detection unit302can detect an abnormally open state of the door222. Then, in response to the detection of the occurrence of abnormal state by the failure detection unit302, the control unit301turns off a conveying motor224to stop a conveyance operation of the sheet S by the inlet roller pair201.

The sheet position determination unit303determines a position of a sheets S remaining inside the sheet discharge option apparatus200using the various sensors, i.e., the inlet sensor216, the conveyance sensor217, and the conveyance sensor218. Then, when the position of the remaining sheet S is determined to be near a branch point of the conveyance path219by the sheet position determination unit303, the control unit301controls the solenoid220to prevent the flapper202from being an obstacle to removal of the remaining sheet. The branch point of the conveyance path219is a branch point where the conveyance path219branches to the conveyance path212and the conveyance path204. The details will be described below with reference to a flowchart.

In the configuration described above, the operation of the sheet discharge option apparatus200in the present example embodiment will be described based on a flowchart illustrated inFIG. 6. The control based on the procedure of the flowchart illustrated inFIG. 6is executed by the control unit301according to a program stored in a read-only memory (ROM) or the like.

The procedure of the flowchart is performed in the following case. The solenoid220receives power supply and the flapper202is in the position illustrated inFIG. 2A, and also, the failure detection unit302detects an occurrence of abnormal state while the conveyance path212conveys a sheet S. In response to the detection of the occurrence of abnormal state, actuators (such as the conveying motor224) other than the solenoid220are turned off and the conveyance operation of the sheet S is stopped.

In step S400, the sheet position determination unit303checks detection results of the inlet sensor216installed on the conveyance path219and the conveyance sensor218installed on the conveyance path212. In a case where both the inlet sensor216and the conveyance sensor218detect the sheet S (YES in step S400), the sheet position determination unit303determines that the sheet S stops at a position where the sheet S extends over the conveyance path219and the conveyance path212(near the branch point of the conveyance path219). In this case, if the solenoid220is turned off, the flapper202traps the sheet S. Thus, in step S401, the control unit301continues to supply power to the solenoid220to maintain the solenoid220in an on state. The flapper202is thus controlled not to move to the position illustrated inFIG. 2B. Consequently, the flapper202does not trap the sheet S. In a case where the door222is opened, the control unit301also continues to supply power to the solenoid220to maintain the solenoid220in an on state. In step S402, the control unit301waits until the sheet S remaining inside the apparatus is removed. In response to a state in which neither the inlet sensor216nor the conveyance sensor218detects the sheet S, the control unit301determines that the remaining sheet S has been removed. In a case where the control unit301determines that the remaining sheet S has been removed (YES in step S402), the processing proceeds to step S403. In step S403, the control unit301stops the power supply to the solenoid220to turn off the solenoid220, to save power consumption. Meanwhile, in step S400, one of the inlet sensor216and the conveyance sensor218does not detect the sheet S (NO in step S400), the control unit301determines that the sheet S does not stop at the position where the sheet S extends over the conveyance path219and the conveyance path212. In this case, the processing proceeds to step S403. In step S403, the control unit301immediately turns off the solenoid220. This completes the control of the flowchart.

As described above, according to the present example embodiment, a conveyance apparatus that improves usability by inhibiting the flapper202that switches a conveyance direction of a sheet S from becoming an obstacle to the user when a sheet S remaining inside the apparatus is removed can be provided.

In the first example embodiment, in a case where both of the inlet sensor216and the conveyance sensor218detect the sheet S, the sheet position determination unit303determines that the sheet S is in the position where the sheet S extends over the conveyance path219and the conveyance path212. In a second example embodiment, the sheet position determination unit303can make a determination correctly in comparison with the first example embodiment by using more criteria for determining the position of the remaining sheet S than those of the first example embodiment. The description of the main portion is similar to that in the first example embodiment, and only a portion different from the first example embodiment will be described.

FIG. 8is a control block diagram of the printer100and the sheet discharge option apparatus200in the present example embodiment. The control block diagram illustrated inFIG. 8is different from that ofFIG. 5in that the control unit301of the sheet discharge option apparatus200includes a timer304. In the present example embodiment, the timer304starts to count when the inlet sensor216detects a tip of a sheet S and resets the count value and restarts to count when the conveyance sensor218detects the tip of the sheet S. Then, the timer304finishes counting when the conveyance operation of the sheet S is stopped after the failure detection unit302detects an occurrence of abnormal state. The sheet position determination unit303determines the position of the remaining sheet S using the count value of the timer304, in addition to detection results by the various sensors, i.e., the inlet sensor216, the conveyance sensor217, and the conveyance sensor218.

In the configuration described above, the operation of the sheet discharge option apparatus200in the present example embodiment will be described with reference to a flowchart illustrated inFIG. 9. The control based on the procedure of the flowchart inFIG. 9is executed by the control unit301according to a program stored in ROM or the like. The condition for performing the procedure of the flowchart are similar to those in the first example embodiment.

In step S500, the sheet position determination unit303checks detection results of the inlet sensor216and the conveyance sensor218. In a case where at least one of the two sensors detects a sheet S (YES in step S500), the processing proceeds to step S501. In step S501, the sheet position determination unit303acquires a count value from the timer304. In step S502, the sheet position determination unit303determines how far the sheet S has been conveyed and where the sheet S is stopped, based on the count value from the timer304and the conveyance speed of the sheet S. In a case where, for example, the inlet sensor216detects the sheet S and the conveyance sensor218does not detect the sheet S, the sheet S may be in a state illustrated inFIG. 10A. The state illustrated inFIG. 10Ais a state in which the tip of the sheet S has not yet reached the conveyance sensor218, and a portion of the sheet S is positioned near the branch point of the conveyance path219. Also, in a case where the inlet sensor216does not detect the sheet S and the conveyance sensor218detects the sheet S, the sheet S may be in a state illustrated inFIG. 10B. The state illustrated inFIG. 10Bis a state in which the rear end of the sheet S has passed through the inlet sensor216, and a portion of the sheet S is positioned near the branch point of the conveyance path219.

In a case where the sheet position determination unit303determines that, as illustrated inFIGS. 10A and 10B, the sheet S is stopped at the position where the sheet S extends over the conveyance path219and the conveyance path212(YES in step S502), the processing proceeds to step S503. In step S503, the control unit301continues to supply power to the solenoid220to maintain the solenoid220in an on state. In step S504, the control unit301waits until the sheet S remaining inside the apparatus is removed by the user. In response to a state in which the sensor which is either the inlet sensor216or the conveyance sensor218having detected the sheet S no longer detects the sheet S, the control unit301determines that the remaining sheet S has been removed. In a case where the control unit301determines that the remaining sheet S has been removed (YES in step S504), the processing proceeds to step S505. In step S505, the control unit301turns off the solenoid220to save power consumption. Meanwhile, in step S500, neither the inlet sensor216nor the conveyance sensor218detects the sheet S (NO in step S500), the control unit301determines that the sheet S is not stopped at the position where the sheet S extends over the conveyance path219and the conveyance path212. In this case, the processing proceeds to step S505. In step S505, the control unit301immediately turns off the solenoid220. In step S502, in a case where the sheet position determination unit303determines that the sheet S is not stopped at the position where the sheet S extends over the conveyance path219and the conveyance path212(NO in step S502), the processing also proceeds to step S505. In step S505, the control unit301stops the power supply to the solenoid220to turn off the solenoid220. This completes the control of the flowchart.

As described above, according to the present example embodiment, the position where the sheet S is stopped can be determined accurately in comparison with the first example embodiment. A conveyance apparatus that improves usability by inhibiting the flapper202that switches the conveyance direction of the sheet S from becoming an obstacle to the user when the sheet S remaining inside the apparatus is removed can be provided.

In the first and second example embodiments described above, the control unit301determines whether to maintain the solenoid220in an on state based on detection results of the inlet sensor216and the conveyance sensor218. However, the first and second example embodiments are not limited to such a configuration. The control unit301may maintain the solenoid220in an on state only based on information indicating that the sheet S is being conveyed toward the sheet discharge tray215, regardless of detection results of the various sensors.

The stopped position of the sheet S may be determined without using the various sensors that detect a sheet S. For example, a timer that starts a measuring operation from a start of driving of the registration roller110to count the time in which a sheet S is conveyed may be provided and a position where a sheet S is stopped may be determined based on the measured value of the timer.

In the first and second example embodiments described above, the position of the flapper202is switched by operating the solenoid220, but the first and second example embodiments are not limited to such a configuration. A stepping motor may be adopted to switch the position of the flapper202. When the power supply to the stepping motor is stopped and the stepping motor is turned off, the force retaining the flapper202in the position illustrated inFIG. 2Ais lost. In such a case, the flapper202may move, under the influence of gravity or the like, to the position illustrated inFIG. 2Bwhere the flapper202traps the sheet S. Thus, in a case where the sheet position determination unit303determines that the sheet S is stopped at the position where the sheet S extends over the conveyance path219and the conveyance path212, the control unit301continues the power supply to the stepping motor to maintain the stepping motor in an on state. Maintaining the stepping motor in an on state is such a control that power supply for a specific phase is continuously performed to maintain a position of a rotor at the current position and is different from such a control that the rotor is rotated by switching a phase for which power is supplied.

Also, in the configuration using a stepping motor, the flapper202may be configured to be able to move to three positions or more. For example, the flapper202moves to the position illustrated inFIG. 2A, the position illustrated inFIG. 2B, and further, a retreating position where the flapper202does not come into contact with a sheet S. The retreating position is a position where the flapper202does not become an obstacle to the user when removing a sheet S in the following both cases: a case where the sheet S is stopped at a position where the sheet S extends over the conveyance path219and the conveyance path204and a case where the sheet S is stopped at the position where the sheet S extends over the conveyance path219and the conveyance path212.

In the first and second example embodiments described above, when a sheet jam occurs inside the sheet discharge option apparatus200and the door222of the sheet discharge option apparatus200is open, the failure detection unit302determines that an abnormal state has occurred. However, the determination is not limited to the case where an abnormal state occurs in the sheet discharge option apparatus200. The failure detection unit302may also determine that an abnormal state has occurred when a sheet jam occurs inside the printer100and a door of the printer100is open.

In the first and second example embodiments, the configuration is described using the sheet discharge option apparatus200removably mounted on the printer100. However, the first and second example embodiments are not limited to such a configuration. The flapper control may be adopted in a sheet conveyance mechanism in which the sheet discharge option apparatus200is fixed to and integrated with the printer100.

In the first and second example embodiments, the above-described control is executed by the control unit301provided in the sheet discharge option apparatus200. Alternatively, the sheet discharge option apparatus200may be configured to be controlled by a control unit provided in the printer100.

In the first and second example embodiments described above, the sheet discharge option apparatus200is used as an example of a conveyance apparatus that conveys the sheet S. The conveyance apparatus may also be a reversing path or a two-sided path of an image forming apparatus or a document conveyance path of a document reading apparatus.

According to the example embodiments of the disclosure, as described above, a conveyance apparatus that improves usability by inhibiting the flapper202that switches a conveyance direction of a sheet S from becoming an obstacle to the user when the sheet S remaining inside the apparatus is removed can be provided.

As an alternative to the above-described configuration, the following configuration can be also considered: the curvature of the conveyance path is set as small as possible and the force with which the flapper202traps the sheet S is made small, so that the flapper202does not become an obstacle to the user when the remaining sheet S is removed. However, the sheet discharge option apparatus200increases in size in such a configuration. In contrast, the present example embodiments eliminate the need to make the curvature of the conveyance path small. Therefore, the sheet discharge option apparatus200can be downsized according to the present example embodiments.

This application claims the benefit of Japanese Patent Application No. 2016-150424, filed Jul. 29, 2016, which is hereby incorporated by reference herein in its entirety.