A conveyance device includes a conveyor that conveys a sheet. A ventilator sends air to the sheet conveyed by the conveyor in a predetermined region. A controller controls the ventilator to change an air capacity of the air at a time when a leading end of the sheet in a sheet conveyance direction is in the predetermined region and at a time when the leading end of the sheet is past the predetermined region.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is based on and claims priority pursuant to 35 U.S.C. § 119(a) to Japanese Patent Application No. 2921-034377, filed on Mar. 4, 2021, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.

BACKGROUND

Technical Field

Exemplary aspects of the present disclosure relate to a conveyance device, a liquid discharge apparatus, and a post-processing apparatus, and more particularly, to a conveyance device, a liquid discharge apparatus incorporating the conveyance device, and a post-processing apparatus incorporating the conveyance device.

Discussion of the Background Art

Related-art image forming apparatuses, such as copiers, facsimile machines, printers, and multifunction peripherals (MCP) having two or more of copying, printing, scanning, facsimile, plotter, and other functions, typically form an image on a recording medium according to image data.

Such image forming apparatuses include an inkjet image forming apparatus that discharges liquid such as ink onto a sheet serving as a recording medium to form an image on the sheet.

SUMMARY

This specification describes below an improved conveyance device. In one embodiment, the conveyance device includes a conveyor that conveys a sheet. A ventilator sends air to the sheet conveyed by the conveyor in a predetermined region. A controller controls the ventilator to change an air capacity of the air at a time when a leading end of the sheet in a sheet conveyance direction is in the predetermined region and at a time when the leading end of the sheet is past the predetermined region.

This specification further describes an improved liquid discharge apparatus. In one embodiment, the liquid discharge apparatus includes a liquid discharger that discharges liquid onto a sheet and the conveyance device described above that conveys the sheet.

This specification further describes an improved post-processing apparatus. In one embodiment, the post-processing apparatus includes the conveyance device described above and a post-processing device that performs post-processing on the sheet conveyed from the conveyance device.

DETAILED DESCRIPTION

Referring to the attached drawings, the following describes embodiments of the present disclosure.

In the drawings for explaining the embodiments of the present disclosure, identical reference numerals are assigned to elements such as members and parts that have an identical function or an identical shape as long as differentiation is possible and a description of those elements is omitted once the description is provided.

FIG.1is a schematic cross-sectional view of an image forming apparatus100according to an embodiment of the present disclosure.

As illustrated inFIG.1, the image forming apparatus100according to this embodiment, also serving as a liquid discharge apparatus, includes an original conveyance device1, a scanner2, an image forming device3, a sheet supply4, a cartridge holder5, a dryer6(e.g., a heating portion), and a sheet ejection portion7. A post-processing apparatus200(e.g., a finisher) is disposed beside the image forming apparatus100.

The original conveyance device1separates an original from other originals placed on an original tray11and conveys the original to an exposure glass13of the scanner2. The original conveyance device1includes a plurality of conveyance rollers serving as original conveyors that convey the original.

The scanner2reads an image on an original placed on the exposure glass13by a user or an image on the original that is conveyed from the original conveyance device1and passes over the exposure glass13. The scanner2includes an optical scanning unit12serving as an image reading portion that reads the image on the original. The optical scanning unit12includes a light source and a charge-coupled device (CCD). The light source irradiates the original on the exposure glass13with light. The CCD serves as an image reader that reads the image on the original with reflected light reflected by the original. Alternatively, a contact image sensor (CIS) or the like may be used as the image reader.

The image forming device3includes a plurality of liquid discharge heads14serving as liquid dischargers that discharge liquid, for example, ink, onto a sheet P. The liquid discharge heads14may employ a serial type system in which the liquid discharge heads14discharge ink while the liquid discharge heads14move in a main scanning direction (e.g., a width direction of the sheet P). Alternatively, the liquid discharge heads14may employ a line type system in which the plurality of liquid discharge heads14stationarily arranged in the main scanning direction discharges ink.

The cartridge holder5is removably mounted with a plurality of ink cartridges15Y,15M,15C, and15Bk. The ink cartridges15Y,15M,15C, and15Bk are replenished with ink in different colors, for example, yellow, magenta, cyan, and black, respectively. Liquid feed pumps supply ink to the liquid discharge heads14from the ink cartridges15Y,15M,15C, and15Bk, respectively.

The sheet supply4includes a plurality of sheet trays16serving as sheet storages, respectively. Each of the sheet trays16loads, as a sheet P onto which an image is to be formed, cut paper cut into a sheet having a predetermined size in a sheet conveyance direction such as an A4 size and a B4 size in advance. Each of the sheet trays16is mounted with a feed roller17serving as a sheet feeder that feeds the sheet P and a separation pad18serving as a sheet separator that separates the sheet P from other sheets P.

The dryer6serves as a heating portion that heats the sheet P. The dryer6facilitates drying of ink on the sheet P under heat. The dryer6also serves as a conveyance device that includes a pair of rotators. As the pair of rotators rotates while sandwiching the sheet P, the pair of rotators conveys the sheet P.

The post-processing apparatus200performs post-processing such as alignment on the sheets P sent from the image forming apparatus100. The post-processing apparatus200includes, as a post-processing portion, a sheet aligner that aligns and ejects the plurality of sheets P. Alternatively, the post-processing portion may be a punch that cuts holes in the sheet P, a stapler that staples the plurality of sheets P, a folder that folds the sheet P in half or in three, or the like.

Referring toFIG.1, a description is provided of basic operations of the image forming apparatus100according to this embodiment.

When the image forming apparatus100receives an instruction to start a print job, a sheet P is fed from one of the plurality of sheet trays16. For example, as the feed roller17rotates, the feed roller17and the separation pad18separate an uppermost sheet P from other sheets P (e.g., a sheaf of sheets P) placed in the sheet tray16and feed the uppermost sheet P.

When the sheet P is conveyed to a conveyance path20extended horizontally inFIG.1and disposed opposite the image forming device3, the image forming device3forms an image on the sheet P. For example, as the liquid discharge heads14are controlled to discharge ink according to image data created by the scanner2that reads an image on an original or print data instructed by a terminal, the liquid discharge heads14discharge ink onto an image bearing face (e.g., an upper face) of the sheet P, thus forming an image on the sheet P. The image formed on the sheet P may be a meaningful image such as characters and drawings or a meaningless image such as patterns.

If the print job instructs duplex printing, the sheet P is conveyed in an opposite direction at a downstream position disposed downstream from the image forming device3in the sheet conveyance direction. Thus, the sheet P is guided to a reverse conveyance path21. For example, after a trailing end of the sheet P passes a first path switch31disposed downstream from the image forming device3in the sheet conveyance direction, the first path switch31switches a conveyance path to the reverse conveyance path21through which the sheet P is conveyed in the opposite direction, Thus, the first path switch31guides the sheet P to the reverse conveyance path21. The sheet P passes through the reverse conveyance path21and is conveyed to the image forming device3again in a state in which the sheet P is reversed. The image forming device3performs image formation as described above, forming an image on a back side of the sheet P.

A second path switch32is disposed downstream from the first path switch31in the sheet conveyance direction. The second path switch32selectively guides the sheet P bearing the image to a conveyance path22provided with the dryer6or a conveyance path23not provided with the dryer6. If the second path switch32guides the sheet P to the conveyance path22provided with the dryer6, the dryer6facilitates drying of ink on the sheet P. Conversely, if the second path switch32guides the sheet P to the conveyance path23not provided with the dryer6, a third path switch33selectively guides the sheet P to a conveyance path24directed to the sheet ejection portion7or a conveyance path25directed to the post-processing apparatus200. A fourth path switch34selectively guides the sheet P that is past the dryer6to a conveyance path26directed to the sheet ejection portion7or a conveyance path27directed to the post-processing apparatus200.

If the sheet P is guided to the conveyance path24or26directed to the sheet ejection portion7, the sheet P is ejected onto the sheet ejection portion7. Conversely, if the sheet P is guided to the conveyance path25or27directed to the post-processing apparatus200, the sheet P is conveyed to the post-processing apparatus200where the sheet P is treated with predetermined post-processing and ejected. Thus, a series of printing processes is completed. The image forming apparatus100according to this embodiment employs a face-down manner ejection system in which the sheet P is ejected onto the sheet ejection portion7or sent to the post-processing apparatus200in a state in which the image bearing face of the sheet P faces down. The image bearing face is adhered with ink when an image is formed on one side (e.g., a front side) of the sheet R Alternatively, the image forming apparatus100may employ a face-up manner ejection system in which the sheet P is ejected onto the sheet ejection portion7or sent to the post-processing apparatus200in a state in which the image bearing face of the sheet P faces up.

The image forming apparatus100according to this embodiment includes a conveyance device40including a plurality of conveyance roller pairs that conveys the sheet P supplied from the sheet supply4.

FIG.2is a diagram of the conveyance device40, illustrating a construction thereof. The conveyance device40is disposed upstream from the image forming device3in a sheet conveyance direction Y in which the sheet P is conveyed.

Referring toFIG.2, the following describes the construction of the conveyance device40according to a first embodiment of the present disclosure.

As illustrated inFIG.2, the conveyance device40according to this embodiment includes a plurality of conveyance roller pairs41serving as conveyors that convey the sheet P. Each of the conveyance roller pairs41includes two conveyance rollers42that contact each other. As the conveyance rollers42rotate, the conveyance rollers42convey the sheet P in the sheet conveyance direction Y. Among the conveyance roller pairs41, a conveyance roller pair41A is disposed immediately upstream from the image forming device3in the sheet conveyance direction Y. The conveyance roller pair41A serves as a correction roller pair that corrects skew of the sheet P. For example, as the sheet P comes into contact with a nip formed between the two conveyance rollers42of the conveyance roller pair41A serving as the correction roller pair while the conveyance roller pair41A does not rotate and is still, the conveyance roller pair41A halts the sheet P temporarily and corrects skew of the sheet P. Thereafter, the conveyance roller pair41A serving as the correction roller pair resumes rotation and conveys the sheet P to the image forming device3. A guide that guides the sheet P is interposed between the conveyance roller pairs41. However, the guide is omitted inFIG.2for simplification.

As illustrated inFIG.2, the conveyance device40according to this embodiment includes a ventilation device50disposed upstream from the conveyance roller pair41A serving as the correction roller pair in the sheet conveyance direction Y The ventilation device50includes a ventilator51and a heater54serving as a heat source. For example, the ventilator51includes a fan52serving as an airflow generator and a duct53serving as an air channel former. The duct53is disposed opposite the sheet P such that the duct53blows air against the sheet P in a direction perpendicular to or substantially perpendicular to the sheet P. The heater54is a sheathed heater (e.g., a nichrome wire heater), a ceramic heater, a halogen heater, a graphite heater, a carbon heater, or the like. According to this embodiment, the heater54is disposed upstream from the fan52in an airflow direction. Alternatively, the heater54may be disposed downstream from the fan52in the airflow direction. The heater54may be combined with the fan52.

In the ventilation device50according to this embodiment, when the heater54starts generating heat and the fan52starts rotating, the heater54warms air into warm air that blows out from the duct53through a vent53a(e.g., an outlet). When the sheet P enters a predetermined region, that is, a blow region A, disposed opposite the vent53a, the warm air blows against the sheet P. Thus, the warm air warms the sheet P before an image is formed on the sheet P. Thereafter, as the sheet P reaches the image forming device3, the image forming device3discharges ink onto the sheet P, thus forming an image on the sheet P. The sheet P warmed by the ventilation device50facilitates drying of ink on the sheet P under heat, thus suppressing smearing of ink or degradation of the image on the sheet P. If volatile ink is used, since the sheet P is warmed in advance, the volatile ink volatilizes and dries quickly.

When the sheet P enters the blow region A of the ventilation device50, as the ventilation device50sends air (e.g., warm air) to the sheet P, the air blown against the sheet P may turn up a leading end of the sheet P in the sheet conveyance direction Y or may flutter the sheet P. Accordingly, the sheet P may not enter the nip formed between the two conveyance rollers42of the conveyance roller pair41A serving as the correction roller pair and may be jammed. Even if the sheet P is not jammed, the sheet P may not be conveyed smoothly, causing conveyance failure.

A description is provided of a construction of a comparative inkjet image forming apparatus.

The comparative inkjet image forming apparatus includes a blower that blows warm air against a sheet or ink on the sheet. While a table placed with the sheet moves, the blower blows the warm air against the sheet or the ink on the sheet, facilitating drying of the ink on the sheet.

However, with a configuration described above in which the blower blows the warm air against the sheet while the table placed with the sheet moves, the warm air blown against the sheet may turn up a leading end of the sheet in a moving direction of the table or may flutter the sheet, causing faulty conveyance of the sheet.

In order to suppress faulty conveyance of the sheet P caused by warm air blown against the sheet P, the conveyance device40according to this embodiment controls blowing by the ventilation device50.

Referring toFIGS.3and4, the following describes blowing by the ventilation device50according to the first embodiment of the present disclosure.

FIG.3is a timing chart of blowing by the ventilation device50according to the first embodiment of the present disclosure.FIG.4is a flowchart of blowing by the ventilation device50according to the first embodiment.

According to this embodiment, when the image forming apparatus100depicted inFIG.1receives an image formation request, the feed roller17feeds a sheet P from the sheet tray16. Accordingly, as illustrated inFIG.4, the ventilation device50starts sending air at a predetermined time in step S101. Thereafter, a sheet sensor43illustrated inFIG.2detects the sheet P. The sheet sensor43serves as a sheet detector that is disposed upstream from the ventilation device50in the sheet conveyance direction Y.

As illustrated inFIG.3, a time T1denotes a time when the sheet sensor43detects the leading end of the sheet P When a predetermined time t elapses from the time T1when the sheet sensor43detects the leading end of the sheet P, the leading end of the sheet P reaches the blow region A. In order to prevent the leading end of the sheet P from being affected by air sent from the ventilation device50, according to this embodiment, when the predetermined time t elapses from the time T1when the sheet sensor43detects the leading end of the sheet P, that is, at a time T2when a controller60depicted inFIG.2determines that the leading end of the sheet P reaches the blow region A (YES in step S102inFIG.4), the controller60controls the ventilation device50to interrupt sending air temporarily in step S103inFIG.4.

While the leading end of the sheet P passes through the blow region A (e.g., during a time period from the time T2to a time T3inFIG.3), the controller60controls the ventilation device50to continue interruption of blowing. Thereafter, at the time T3when the controller60determines that the leading end of the sheet P has passed the blow region A (YES in step S104inFIG.4), the controller60controls the ventilation device50to resume sending air in step S105inFIG.4. The controller60determines the time T3when the leading end of the sheet P has passed the blow region A based on a conveyance time or the like of the sheet P, that elapses from the time T1when the sheet sensor43detects the leading end of the sheet P.

After the ventilation device50resumes sending air, the controller60controls the ventilation device50to continue sending air until a time T8when a leading end of a subsequent sheet P reaches the blow region A. For example, if the controller60determines that the subsequent sheet P is to be conveyed (YES in step S106inFIG.4), at the time T8when the controller60determines that the leading end of the subsequent sheet P reaches the blow region A, the controller60controls the ventilation device50to interrupt sending air temporarily. Until the controller60determines that no subsequent sheet P is to be conveyed, the controller60repeats control processes described above (e.g., steps S102to S105). If the controller60determines that no subsequent sheet P is to be conveyed (NO in step S106inFIG.4), the controller60controls the ventilation device50to stop sending air in step S107inFIG.4, finishing image formation.

As illustrated inFIG.3, a time T4denotes a time when the sheet sensor43detects the trailing end of the sheet P in the sheet conveyance direction Y A time T5denotes a time when the trailing end of the sheet P reaches the blow region A. A time T6denotes a time when the trailing end of the sheet P has passed the blow region A. A time T7denotes a time when the sheet sensor43detects the leading end of the subsequent sheet P. A time T9denotes a time when the leading end of the subsequent sheet P has passed the blow region A.

As described above, according to this embodiment, after the leading end of the sheet P reaches the blow region A and before the leading end of the sheet P is past the blow region A, the ventilation device50interrupts sending air to the sheet P temporarily, preventing the air from turning up the leading end of the sheet P and fluttering the sheet P. Hence, according to this embodiment, the sheet P enters the nip formed between the conveyance rollers42of the conveyance roller pair41A serving as the correction roller pair readily, improving conveyance of the sheet P.

After the leading end of the sheet P is past the blow region A, until the leading end of the subsequent sheet P reaches the blow region A, that is, during a time period from the time T3to the time T8depicted inFIG.3, the ventilation device50continues sending air. Accordingly, warm air blown out from the ventilation device50warms the sheet P effectively. For example, according to this embodiment, also after the trailing end of the sheet P passes the blow region A (e.g., after the time T6depicted inFIG.3), the ventilation device50continues sending air. Accordingly, warm air blown out from the ventilation device50warms the conveyance path20depicted inFIG.1and a periphery thereof, warming the subsequent sheet P effectively and facilitating drying of ink on the subsequent sheet P.

A description is provided of embodiments that are different from the first embodiment described above.

Hereinafter, the embodiments are described mainly of configurations that are different from those of the first embodiment described above. A description of other configurations that are basically common to the first embodiment described above is omitted properly,

FIG.5is a timing chart of blowing by the ventilation device50according to a second embodiment of the present disclosure.FIG.6is a flowchart of blowing by the ventilation device50according to the second embodiment.

As illustrated inFIG.5, according to the second embodiment of the present disclosure, during a time period after the image forming apparatus100depicted inFIG.1receives an image formation request until the time T3when a leading end of a previous sheet P (e.g., a first sheet P) is past the blow region A, and during a time period after the time T6when a trailing end of the previous sheet P is past the blow region A until the time T9when a leading end of a subsequent sheet P (e.g., a second sheet P) is past the blow region A, the controller60controls the ventilation device50to interrupt sending air. For example, according to this embodiment, solely during a time period from the time T3when the leading end of the sheet P reaches the blow region A until the time T6when the trailing end of the sheet P is past the blow region A, the controller60controls the ventilation device50to send air in steps S201to S204inFIG.6.

For example, in step S201, the controller60determines whether or not the leading end of the previous sheet P reaches the blow region A. If the controller60determines that the leading end of the previous sheet P reaches the blow region A (YES in step S201), the controller60controls the ventilation device50to start sending air in step S202. In step S203, the controller60determines whether or not the trailing end of the previous sheet P has passed the blow region A. If the controller60determines that the trailing end of the previous sheet P has passed the blow region A (YES in step S203), the controller60controls the ventilation device50to interrupt sending air in step S204. In step S205, the controller60determines whether or not the subsequent sheet P is to be conveyed. If the controller60determines that the subsequent sheet P is to be conveyed (YES in step S205), the controller60controls the ventilation device50to blow air similarly.

As described above, according to this embodiment, solely while the sheet P passes through the blow region A, the controller60controls the ventilation device50to send air, reducing power consumption for sending air. While the controller60controls the ventilation device50to interrupt sending air, the controller60may control the heater54to interrupt heat generation. In this case, the conveyance device40reduces power consumption further.

FIG.7is a timing chart of blowing by the ventilation device50according to a third embodiment of the present disclosure.FIG.8is a flowchart of blowing by the ventilation device50according to the third embodiment.

As illustrated inFIG.7, according to the third embodiment of the present disclosure, during a time period from the time T1when the sheet sensor43detects the leading end of the sheet P until the time T3when the leading end of the sheet P is past the blow region A, the controller60controls the ventilation device50to send air with a decreased air capacity (e.g., a weak wind force or a slow wind velocity) that is small enough to prevent the leading end of the sheet P from turning up in steps S301and S302inFIG.8. For example, in step S301, the controller60determines whether or not the sheet sensor43detects the leading end of the sheet P. If the controller60determines that the sheet sensor43detects the leading end of the sheet P (YES in step S301), the controller60controls the ventilation device50to start sending air with the decreased air capacity in step S302. In step S303, the controller60determines whether or not the leading end of the sheet P has passed the blow region A at the time T3. If the controller60determines that the leading end of the sheet P has passed the blow region A at the time T3(YES in step S303), the controller60increases the air capacity of the ventilation device50in step S304. For example, the controller60increases the wind force or the wind velocity of the ventilation device50. In step S305, the controller60determines whether or not the trailing end of the sheet P has passed the blow region A at the time T6. If the controller60determines that the trailing end of the sheet P has passed the blow region A at the time T6(YES in step S305), the controller60controls the ventilation device50to interrupt sending air in step S306. In step S307, the controller60determines whether or not the subsequent sheet P is to be conveyed. If the controller60determines that the subsequent sheet P is to be conveyed (YES in step S307), the controller60repeats steps S301to S306similarly.

According to this embodiment, the controller60controls the ventilation device50to decrease the wind capacity while the leading end of the sheet P passes through the blow region A, thus preventing air from turning up or fluttering the sheet P. The controller60changes the wind force of the ventilation device50by changing the rotation speed of the fan52, the outlet area of the vent53aof the duct53, or the like. According to this embodiment, the ventilation device50starts sending air at the time T1depicted inFIG.7when the sheet sensor43detects the leading end of the sheet P. Alternatively, the ventilation device50may start sending air at the time T2when the controller60determines that the leading end of the sheet P reaches the blow region A.

FIG.9is a diagram of a conveyance device40A according to a fourth embodiment of the present disclosure, illustrating a construction of the conveyance device40A.

As illustrated inFIG.9, the conveyance device40A according to the fourth embodiment of the present disclosure includes a ventilation device50A including a ventilator51A. The ventilator51A includes a duct53A that is bent such that a vent53aA (e.g., an outlet) is extended diagonally with respect to the sheet P. Thus, the vent53aA discharges air in an airflow direction that is diagonal to the sheet P and is directed upstream in the sheet conveyance direction Y The vent53aA discharges warm air in the airflow direction that separates from the image forming device3, preventing the warm air from increasing the temperature of the image forming device3. According to this embodiment, the image forming device3does not suffer from temperature increase, suppressing increase in viscosity of ink, faulty discharging of ink, and the like. Thus, the image forming device3retains proper performance.

The duct53A including the vent53aA according to this embodiment is preferably installed in a conveyance device40AM configured as illustrated inFIG.10. In the conveyance device40AM configured as illustrated inFIG.10, the ventilation device50A is interposed between the image forming device3and the conveyance roller pair41A serving as the correction roller pair. For example, the conversance roller pair41A serving as the correction roller pair is not interposed between the ventilation device50A and the image forming device3. Hence, an airflow flown from the ventilation device50A tends to move to the image forming device3. Accordingly, if the ventilation device50A sends air in an airflow direction that is perpendicular to or substantially perpendicular to the sheet P, the air (e.g., warm air) sent from the ventilation device50A may move to the image forming device3and may adversely affect an ink discharge direction in which the liquid discharge heads14discharge ink. To address this circumstance, the ventilation device50A according to this embodiment sends air in the airflow direction directed upstream in the sheet conveyance direction Y, preventing the air from moving to or entering the liquid discharge heads14. Accordingly, the airflow from the ventilation device50A does not adversely affect the ink discharge direction in which the liquid discharge heads14discharge ink, preventing degradation in quality of an image formed on the sheet P.

The controller60controls blowing according to any one of the embodiments described above. As the controller60employs any one of the embodiments described above, the controller60also controls the ventilation device50A according to the fourth embodiment, preventing air sent from the ventilation device50A from turning up or fluttering the sheet P. The controller60employs any one of the embodiments described above similarly also with embodiments described below.

FIG.11is a diagram of a conveyance device40B according to a fifth embodiment of the present disclosure, illustrating a construction of the conveyance device40B.

As illustrated inFIG.11, the conveyance device40B according to the fifth embodiment of the present disclosure includes the duct53that sends air in the airflow direction that is not diagonal to the sheet conveyance direction Y or the sheet P but is perpendicular to or substantially perpendicular to the sheet conveyance direction Y or the sheet P, like the duct53according to the first embodiment described above with reference toFIG.2. Accordingly, a part of warm air blown against the sheet, P may be reflected by the sheet P and moved toward the image forming device3. To address this circumstance, according to this embodiment, as illustrated inFIG.11, a thermal insulator55is interposed between the ventilation device50and the image forming device3. For example, the thermal insulator55is disposed at a downstream position disposed downstream from the ventilator51in the sheet conveyance direction Y. The thermal insulator55is made of a thermal insulation material such as silicone sponge and urethane foam.

As described above, according to this embodiment, the thermal insulator55is interposed between the ventilation device50and the image forming device3, preventing warm air blown out from the ventilation device50from increasing the temperature of the image forming device3. Thus, according to this embodiment, the image forming device3does not suffer from temperature increase, suppressing increase in viscosity of ink, faulty discharging of ink, and the like. Thus, the image forming device3retains proper performance. The construction of the conveyance device40B according to this embodiment may also be applied to other embodiments of the present disclosure.

FIG.12is a diagram of a conveyance device40C according to a sixth embodiment of the present disclosure, illustrating a construction of the conveyance device40C.

As illustrated inFIG.12, the conveyance device40C according to the sixth embodiment of the present disclosure includes a thermal insulator55C interposed between the ventilation device50and the cartridge holder5. The cartridge holder5is disposed upstream from the ventilation device50in the sheet conveyance direction Y For example, the thermal insulator55C is disposed at an upstream position disposed upstream from the ventilator51in the sheet conveyance direction Y The thermal insulator55C is made of the thermal insulation material described above.

As described above, according to this embodiment, the thermal insulator55C is interposed between the ventilation device50and the cartridge holder5, preventing warm air blown out from the ventilation device50from increasing the temperature of the cartridge holder5. Accordingly, the ink cartridges15Y,15M,15C, and15Bk mounted on the cartridge holder5do not suffer from temperature increase, suppressing increase in viscosity of ink, clogging of ink, and the like. The construction of the conveyance device40C according to this embodiment may also be applied to other embodiments of the present disclosure.

FIG.13is a diagram of a conveyance device40D according to a seventh embodiment of the present disclosure, illustrating a construction of the conveyance device401).

As illustrated inFIG.13, the conveyance device40D according to the seventh embodiment of the present disclosure includes a wall56interposed between the ventilation device50and the image forming device3. The wall56prevents air (e.g., warm air) blown out from the ventilation device50from moving toward the image forming device3. The wall56is a soft, thin sheet such as Mylar®.

As illustrated inFIG.13, the wall56extends continuously throughout an entire span of a conveyance belt44in an axial direction thereof or a width direction X of the sheet P, which is perpendicular to the sheet conveyance direction Y. The wall56contacts a conveyance face44aof the conveyance belt44serving as a conveyor that is disposed opposite the liquid discharge heads14. The conveyance belt44bears the sheet P on the conveyance face44aand conveys the sheet P. The wall56separates an ink discharge clearance interposed between the liquid discharge heads14and the conveyance belt44from a ventilation chamber where the ventilation device50is situated.

According to this embodiment, even if air (e.g., warm air) blown out from the ventilation device50flows to the image forming device3, the wall56prevents the air from entering the ink discharge clearance. Accordingly, the wall56reduces adverse effects caused by an airflow from the ventilation device50and inflicted on the ink discharge direction in which the liquid discharge heads14discharge ink.

According to this embodiment, as the sheet P enters a nip formed between the conveyance belt44that rotates and the wall56, the conveyance belt44conveys the sheet P. Since the conveyance belt44rotates, the conveyance face44aof the conveyance belt44slides over the wall56. To address this circumstance, as illustrated inFIG.14, the wall56includes a contact portion that contacts the conveyance face44aof the conveyance belt44and includes a tip56a. The contact portion of the wall56is oriented in the sheet conveyance direction Y, that is, a rotation direction of the conveyance belt44. Accordingly, even if the conveyance belt44rotates, the tip56aof the wall56is not turned up. Additionally, according to this embodiment, the wall56includes a slope56hthat defines a gap G between the wall56and the conveyance face44aof the conveyance belt44. The gap G increases gradually from a contact position where the wall56contacts the conveyance face44aof the conveyance belt44to an upstream position on the wall56, which is disposed upstream from the contact position in the sheet conveyance direction Y. Hence, as the conveyance roller pair41conveys the sheet P to the conveyance belt44, the wall56guides the leading end of the sheet P along the slope56b. Thus, the sheet P enters the nip formed between the wall56and the conveyance face44aof the conveyance belt44smoothly.

FIGS.13and14illustrate the wall56that contacts the conveyance belt44. Alternatively, as illustrated inFIG.15, a conveyance device44E may include a guide45that contacts the wall56. The guide45includes a guide face45athat contacts and guides the sheet P. The wall56contacts the guide face45athroughout an entire span of the guide45in the width direction X of the sheet P. Thus, the wall56prevents air blown out from the ventilation device50from entering an ink discharge clearance between the liquid discharge heads14and the guide45. A shape and a material of the wall56depicted inFIG.15are equivalent to a shape and a material of the wall56depicted inFIGS.13and14.

FIG.16is a diagram of a conveyance device40F according to an eighth embodiment of the present disclosure, illustrating a construction of the conveyance device40F.

As illustrated inFIG.16, the conveyance device40F according to the eighth embodiment of the present disclosure includes a roller57interposed between a wall56F and the conveyance belt44. The roller57serves as a rotator and is cylindrical. The wall56F includes a bent portion56cdisposed at a lower end of the wall56F inFIG.16. The lower end is bent into the bent portion56cthat extends horizontally inFIG.16. A lower face of the bent portion56ccontacts an outer circumferential surface of the roller57. The roller57extends in the width direction X of the sheet P. The roller57contacts both the bent portion56cof the wall56F and the conveyance face44aof the conveyance belt44continuously throughout the entire span of the conveyance belt44in the width direction X of the sheet P.

As described above, according to this embodiment, the roller57and the wall56F separate the ink discharge clearance interposed between the liquid discharge heads14and the conveyance belt44from the ventilation chamber where the ventilation device50is situated. Hence, according to this embodiment also, the roller57and the wall56F prevent air (e.g., warm air) blown out from the ventilation device50from entering the ink discharge clearance, reducing adverse effects caused by an airflow from the ventilation device50and inflicted on the ink discharge direction in which the liquid discharge heads14discharge ink.

The sheet P conveyed from an upstream position upstream from the roller57in the sheet conveyance direction Y enters a nip formed between the conveyance belt44and the roller57. The sheet P is conveyed by the conveyance belt44that rotates and the roller57that rotates in accordance with rotation of the conveyance belt44. Thus, according to this embodiment, the sheet P does not rub the wall56F. Accordingly, the roller57prevents generation of sliding friction with respect to the sheet P and conveys the sheet P smoothly.

Like the wall56described above with reference toFIG.13, the wall56F is a soft, thin sheet such as Mylar®. A material and a shape of the roller57are not limited unless the material and the shape disturb conveyance of the sheet P and are selected properly. For example, the roller57is made of foam rubber such as silicone sponge or other thermal insulation material, suppressing temperature decrease of the sheet P when the sheet P contacts the roller57. For example, the roller57made of a thermal insulation material suppresses drawing of heat from the sheet P when the sheet P contacts the roller57. Accordingly, the roller57conveys the sheet P to the image forming device3in a state in which the sheet P stores heat properly. Thereafter, ink on the sheet P dries effectively.

In order to suppress temperature decrease of the sheet P when the sheet P contacts the roller57or when the sheet P contacts the wall56depicted inFIGS.13to15, the ventilation device50may send warm air to warm up the roller57or the wall56in advance. For example, while the image forming apparatus100is warmed up immediately after the image forming apparatus100is powered on, the roller57or the wall56does not store heat. Hence, after the image forming apparatus100is powered on, before conveyance of a first sheet P starts after the image forming apparatus100receives an image formation request, the ventilation device50may start sending air. Alternatively, after a previous image formation finishes, the image forming apparatus100may receive a subsequent image formation request after an interval. In this case also, the ventilation device50may continue sending air for a predetermined time period to warm up the roller57or the wall56. Accordingly, the roller57or the wall56suppresses temperature decrease of the sheet P when the sheet P contacts the roller57or the wall56. Thereafter, ink on the sheet P dries effectively.

FIG.17is a diagram of a conveyance device40G according to a ninth embodiment of the present disclosure, illustrating a construction of the conveyance device40G.

As illustrated inFIG.17, the conveyance device40G according to the ninth embodiment of the present disclosure includes a ventilation device50G including a valve58that opens and closes an air channel inside the duct53. The valve58is pivotable about a shaft58adisposed inside the duct53. As the valve58pivots, the valve58opens and closes the air channel inside the duct53. For example, when the valve58is disposed at an open position indicated with a solid line inFIG.17, the air channel opens. When the valve58is disposed at a closed position indicated with an alternate long and two short dashes line inFIG.17, the air channel closes.

FIG.18illustrates the controller60that controls the valve58to open and close the air channel. In addition to the valve58that opens and closes the air channel, the controller60also controls (e.g., drives and rotates) the fan52to send air and controls (e.g., drives and rotates) the conveyance rollers42to convey the sheet P. Additionally, the controller60receives a detection signal from the sheet sensor43and controls the valve58, the fan52, and the conveyance rollers42based on the received detection signal.

As described above, according to this embodiment, as the valve58opens and closes the air channel inside the duct53, the ventilation device50G interrupts and resumes sending air. Hence, according to this embodiment, as the controller60controls the valve58to open and close the air channel based on the detection signal sent from the sheet sensor43, the ventilation device50G interrupts sending air while the leading end of the sheet P passes through the blow region A, thus preventing air from turning up or fluttering the sheet P. Alternatively, the valve58may slide and move in a horizontal direction or the like inFIG.17to open and close the air channel.

FIG.19is a diagram of an image forming apparatus100I-1according to a tenth embodiment of the present disclosure, also serving as a liquid discharge apparatus, illustrating a construction of the image forming apparatus100H.FIG.19is a cross-sectional view of the image forming apparatus100H, illustrating a ventilation device50H seen from an upstream position disposed upstream from the ventilation device50H in the sheet conveyance direction Y. A left side inFIG.19is a front face (e.g., a from) of the image forming apparatus100H. A right side inFIG.19is a rear face (e.g., a rear) of the image forming apparatus100H.

As illustrated inFIG.19, according to the tenth embodiment of the present disclosure, the ventilation device50H does not incorporate the heater54depicted inFIG.2. The ventilation device50H uses heat generated by a driver36, a power supply37, and an electrical component38disposed inside the image forming apparatus100H. The driver36drives the image forming device3, the conveyance rollers42, and the like. The power supply37supplies power to various elements inside the image forming apparatus100H. The power supply37supplies power to electronic components of the electrical component38that controls operations of various elements inside the image forming apparatus100H. Accordingly, the driver36, the power supply37, and the electrical component38generate heat. The fan52supplies air (e.g., warm air) warmed by heat generated by the driver36, the power supply37, and the electrical component38into the duct53. The warm air is sent to a sheet P not formed with an image yet through the vent53aof the duct53. InFIG.19, the fan52is disposed at an upstream end of the duct53in an airflow direction. Alternatively, the fan52may be disposed in a partway of the air channel inside the duct53. Yet alternatively, the fan52may be disposed at a downstream portion of the duct53in the airflow direction at a position in proximity to the vent53a.

As described above, according to this embodiment, in order to warm the sheet P before an image is formed on the sheet P, instead of heat generated by a heat source such as a heater, the ventilation device50H uses heat generated by the driver36, the power supply37, and the electrical component38, reducing power consumption for warming the sheet P. For example, heat generated by heat radiators such as the driver36, the power supply37, and the electrical component38that radiate heat regardless of primary objectives and functions thereof is used effectively as heat (e.g., warm air) that warms the sheet P, thus reducing power consumption for supplying heat and costs. Additionally, like this embodiment, if the ventilation device50H does not use an exclusive heater for drying the sheet P, the ventilation device50H reduces manufacturing costs of the image forming apparatus100H and simplifies the construction of the image forming apparatus100H, improving reliability of the image forming apparatus100H.

The image forming apparatus100H according to this embodiment further includes a rear chamber10accommodating the driver36, the power supply37, and the electrical component38and a front chamber9accommodating the image forming device3and the like. Since the rear chamber10is separated from the front chamber9, dry air (e.g., warm air) inside the rear chamber10is sent to the sheet P. For example, according to this embodiment, the image forming apparatus100H accommodates a front frame101and a rear frame102serving as supports that support the image forming device3, the duct53, and the like. The image forming device3, the sheet supply4, the duct53, and the like are disposed in the front chamber9disposed frontward from the rear frame102. The driver36, the power supply37, and the electrical component38are disposed in the rear chamber10disposed rearward from the rear frame102.

In the rear chamber10configured as described above, no ink is discharged and no sheet P adhered with ink is conveyed. Hence, the rear chamber10contains less moisture that generates as ink on the sheet P evaporates than the front chamber9. Accordingly, the rear chamber10supplies air (e.g., warm air) containing less moisture to the sheet P. Thus, the warm air reduces moisture on the sheet P while warming the sheet P, facilitating drying of ink adhered to the sheet P effectively.

FIG.20is a diagram of an image forming apparatus100I according to an eleventh embodiment of the present disclosure, illustrating a construction of the image forming apparatus100I.

As illustrated inFIG.20, the image forming apparatus100I according to the eleventh embodiment of the present disclosure, also serving as a liquid discharge apparatus, includes a ventilation device50I that uses heat generated by the dryer6(e.g., a heating portion). Hence, the ventilation device50I according to this embodiment also does not incorporate an exclusive heater (e.g., the heater54).

Referring toFIG.21, a description is provided of one example of a construction of the dryer6.

As illustrated inFIG.21, the dryer6includes a heating belt90, a pressure roller91, heaters92, a nip formation pad93, a stay94, a reflector95, and belt holders96.

The heating belt90is an endless belt or film serving as a heating rotator heated by the heaters92. The heating belt90includes a base layer90aand a release layer90b. The base layer90ais an endless layer having flexibility. The release layer90bis mounted on an outer circumferential surface of the base layer90a.

The pressure roller91is an elastic roller serving as a pressure rotator pressed against the heating belt90. The pressure roller91includes a base layer91a, an elastic layer91b, and a release layer91c. The base layer91a(e.g., a core metal) is tubular or cylindrical. The elastic layer91bis mounted on an outer circumferential surface of the base layer91a. The release layer91cis mounted on an outer circumferential surface of the elastic layer91b.

The heater92is a halogen heater serving as a heat source that heats the heating belt90. Alternatively, instead of the halogen heater, a heater of various types, for example, a heater that radiates heat, such as a carbon heater and a ceramic heater, or a heater that employs an electromagnetic induction heating system, may be used as the heat source.

The nip formation pad93is disposed within a loop formed by the heating belt90. The nip formation pad93and the pressure roller91sandwich the heating belt90and define a nip N between the pressure roller91and the heating belt90. The nip formation pad93and the pressure roller91are biased and approached each other relatively. Accordingly, the nip formation pad93and the pressure roller91are pressed against each other via the heating belt90, forming the nip N between the pressure roller91and the heating belt90.

The stay94serves as a support that supports the nip formation pad93, preventing the nip formation pad93from being bent by pressure from the pressure roller91, The stay94contacts an opposite face of the nip formation pad93, which is opposite a pressure roller side face of the nip formation pad93, which is disposed opposite the pressure roller91. Thus, the stay94supports the nip formation pad93.

The reflector95reflects light (e.g., infrared light) emitted from the heaters92or heat radiated from the heaters92toward the heating belt90. Since the reflector95is disposed within the loop formed by the heating belt90, the reflector95reflects light emitted from the heaters92to an inner circumferential surface of the heating belt90.

The belt holders96are disposed at both lateral ends of the heating belt90in a longitudinal direction thereof, respectively, thus serving as a holder pair that supports the heating belt90. Each of the belt holders96is C-shaped or cylindrical. The belt holders96are inserted into the loop formed by the heating belt90at both lateral ends of the heating belt90in the longitudinal direction thereof, respectively. Thus, the belt holders96rotatably support the heating belt90. While the heating belt90rests and does not rotate, the belt holders96basically support the heating belt90in a state in which the heating belt90is not applied with tension in a circumferential direction thereof by a free belt system.

As illustrated inFIG.21, as a driver disposed inside a body of the image forming apparatus100I drives and rotates the pressure roller91, a driving force is transmitted from the pressure roller91to the heating belt90through the nip N, rotating the heating belt90in accordance with rotation of the pressure roller91. As each of the heaters92generates heat, each of the heaters92disposed opposite the inner circumferential surface of the heating belt90heats the heating belt90. In a state in which the temperature of the heating belt90reaches a predetermined temperature (e.g., a drying temperature), as the sheet P bearing an image enters the nip N formed between the heating belt90and the pressure roller91, the image bearing face (e.g., a face adhered with ink I) of the sheet P is brought into contact with the heating belt90and heated by the heating belt90, thus facilitating drying of the ink T on the sheet P. Thereafter, the heating belt90and the pressure roller91, which rotate, eject the sheet P from the dryer6and convey the sheet P to the sheet ejection portion7or the post-processing apparatus200depicted inFIG.1.

As described above, as the heaters92heat the heating belt90in the dryer6, a part of heat dissipates from the heating belt90into circumambient air and blows as warm air. If the warm air is left unused, the warm air is discharged to an outside of the image forming apparatus100I and is not used effectively. To address this circumstance, according to this embodiment, the warm air that blows in a periphery of the dryer6is used to warm the sheet P before an image is formed on the sheet P.

For example, as illustrated inFIG.20, a suction fan59sucks the warm air generated in the periphery of the dryer6through inlets61aof a first duct61. The first duct61extends throughout an entire span of the heating belt90of the dryer6in the longitudinal direction of the heating belt90or the width direction of the sheet P, The dust duct61includes the plurality of inlets61athat is disposed opposite the heating belt90. The first duct61guides the warm air sucked through the inlets61ato a second duct62disposed in the rear chamber10. A fan64guides the warm air to a third duct63. The third duct63is disposed opposite a conveyance path through which the sheet P not formed with an image yet is conveyed. The third duct63sends the warm air to the sheet P not formed with the image yet through a plurality of vents63a(e.g., outlets) of the third duct63.

As described above, according to this embodiment, the plurality of ducts serving as air channel formers, that is, the first duct61, the second duct62, and the third duct63, sends the warm air in the periphery of the dryer6to the sheet P. Thus, heat generated by the heaters92of the dryer6is used effectively as heat that warms the sheet P before the image is formed on the sheet P. Hence, the image forming apparatus100I according to this embodiment reduces power consumption compared to a configuration in which both the dryer6and the ventilation device50I incorporate heaters, respectively. For example, the dryer6and the ventilation device50I share the heaters92as common heaters, reducing power consumption and manufacturing costs.

FIG.22illustrates an image forming apparatus100I according to a twelfth embodiment of the present disclosure. The image forming apparatus100J, also serving as a liquid discharge apparatus, includes a ventilation device50J. The ventilation device50J includes an inlet62athat sucks heat generated by the heat radiators such as the driver36and the power supply37disposed in the rear chamber10. Thus, the ventilation device50J uses the heat generated by the heat radiators in addition to heat generated by the dryer6, thus reducing power consumption further.

FIG.23is a diagram of a conveyance device40K according to a thirteenth embodiment of the present disclosure, illustrating a construction of the conveyance device40K.

As illustrated inFIG.23, the conveyance device40K according to the thirteenth embodiment of the present disclosure includes a ventilation device50K that sends air to the sheet P after an image is formed on the sheet P, in addition to sending air before the image is formed on the sheet P, unlike the embodiments described above. For example, as illustrated inFIG.23, the ventilation device50K includes a ventilator51K including an upstream ventilating portion51AK and a downstream ventilating portion51BK. The upstream ventilating portion51AK is disposed upstream from the liquid discharge heads14in the sheet conveyance direction Y and sends air to the sheet P. The downstream ventilating portion51BK is disposed downstream from the liquid discharge heads14in the sheet conveyance direction Y and sends air to the sheet P.

The ventilator51K according to this embodiment includes a single duct53K serving as an air channel former and two fans, that is, a first fan52A and a second fan52B, serving as airflow generators, respectively. The duct53K extends continuously from the upstream ventilating portion51AK to the downstream ventilating portion51BK. The upstream ventilating portion51AK and the downstream ventilating portion51BK include vents53aK and53bK (e.g., outlets), respectively. One of the two fans, that is, the first fan52A, is disposed in the upstream ventilating portion51AK inside the duct53K. The first fan52A generates an airflow toward the vent53aK of the upstream ventilating portion51AK. Conversely, another one of the two fans, that is, the second fan52B, is disposed in the downstream ventilating portion51BK inside the duct53K. The second fan52B generates an airflow toward the vent53bK of the downstream ventilating portion51BK. A heater54K serving as a heat source is disposed in the downstream ventilating portion51BK inside the duct53K.

In the conveyance device40K according to this embodiment having the construction described above, the heater54K generates heat that warms air into warm air. The first fan52A blows the warm air out through the vent53aK of the upstream ventilating portion51AK against the sheet P before an image is formed on the sheet P. Thereafter, the image forming device3forms the image on the sheet P, When the sheet P reaches the downstream ventilating portion51BK, the second fan52B blows the warm air out through the vent53bK of the downstream ventilating portion51BK against the sheet P after the image is formed on the sheet P.

As described above, according to this embodiment, the warm air blows against the sheet P before and after the image is formed on the sheet P, drying ink on the sheet P more effectively. According to this embodiment, a heating portion (e.g., the downstream ventilating portion51BK) disposed downstream from the liquid discharge heads14in the sheet conveyance direction Y heats the sheet P. The duct53K guides the warm air generated inside the downstream ventilating portion51BK to the upstream ventilating portion51AK. Thus, the downstream ventilating portion51BK and the upstream ventilating portion51AK share heat generated by the heater54K. Accordingly, the conveyance device40K does not incorporate a plurality of heaters, attaining reduction of manufacturing costs and downsizing of the conveyance device40K.

As illustrated inFIG.24, the conveyance device40K may further include ducts65that collect the warm air sent from the downstream ventilating portion51BK. The ducts65sandwich a guide66in the width direction of the sheet P. The guide66defines a conveyance path through which the sheet P is conveyed. Inlets65asuck and collect the warm air blown out toward the guide66or the sheet P. The ducts65are coupled with the upstream ventilating portion51AK and guide the collected warm air to the upstream ventilating portion51AK. Thus, the ducts65guide the warm air sent from the downstream ventilating portion51BK to the upstream ventilating portion51AK.

According to this embodiment also, as illustrated inFIG.23, while the leading end of the sheet P passes through blow regions A1and A2defined by the upstream ventilating portion51AK and the downstream ventilating portion51BK, respectively, like in the embodiments described above, the controller60controls the ventilation device50K to interrupt sending air from each of the upstream ventilating portion51AK and the downstream ventilating portion51BK or decrease the air capacity of each of the upstream ventilating portion51AK and the downstream ventilating portion51BK. Accordingly, the conveyance device40K prevents air from turning up or fluttering the sheet P, improving conveyance of the sheet P.

The above describes the embodiments of the present disclosure. However, the technology of the present disclosure is not limited to the embodiments described above and is modified within the scope of the present disclosure.

An image forming apparatus applied with any one of the embodiments of the present disclosure is not limited to the image forming apparatus100depicted inFIG.1. For example, each of the embodiments of the present disclosure is also applicable to image forming apparatuses100L and100M illustrated inFIGS.25and26, respectively.

The following describes constructions of the image forming apparatuses100L and100M to which any one of the embodiments of the present disclosure is applicable. The constructions of the image forming apparatuses100L and100M, respectively, are described mainly for a part that is not shared by the image forming apparatus100depicted inFIG.1. A description of other part that is shared by the image forming apparatus100and therefore is described above is omitted.

As illustrated inFIG.25, the image forming apparatus100L also serving as a liquid discharge apparatus, like the image forming apparatus100depicted inFIG.1and described above in the embodiments, includes the original conveyance device1, the scanner2, the image forming device3, the sheet supply4, the cartridge holder5, the dryer6, and the sheet ejection portion7. The image firming apparatus100L further includes a bypass sheet supply8, Unlike the image forming device3depicted inFIG.1, the image forming device3depicted inFIG.25is disposed opposite a conveyance path80inclined with respect to a horizontal direction inFIG.25such that a sheet P is conveyed obliquely with respect to the horizontal direction through the conveyance path80.

The bypass sheet supply8includes a bypass tray68and a feed roller69. The bypass tray68serves as a table where a sheet P is placed. The feed roller69serves as a feeder that feeds the sheet P from the bypass tray68. The bypass tray68is attached to a body of the image forming apparatus100L. As the bypass tray68pivots, the bypass tray68is opened and closed with respect to the body of the image forming apparatus100L. As a user opens the bypass tray68as illustrated inFIG.25, the user places the sheet P on the bypass tray68so that the feed roller69feeds the sheet P.

When the image forming apparatus100L depicted inFIG.25receives an instruction to start a print job, the sheet supply4or the bypass sheet supply8supplies a sheet P that is conveyed to the image forming device3. When the sheet P reaches the image forming device3, the liquid discharge heads14discharge ink onto the sheet P, forming an image on the sheet P.

If the print job instructs duplex printing, after the sheet P passes the image forming device3, the sheet P is conveyed in an opposite direction. A first path switch71guides the sheet P to a reverse conveyance path81. The sheet P passes through the reverse conveyance path81and is conveyed to the image forming device3again in a state in which the sheet P is reversed. The image forming device3forms an image on the back side of the sheet P.

The sheet P bearing the image on one side (e.g., the front side) or both sides (e.g., the front side and the back side) thereof is conveyed to the dryer6that dries ink on the sheet P. A second path switch72selectively guides the sheet P that has passed the dryer6to a conveyance path82directed to an upper stage of the sheet ejection portion7or a conveyance path83directed to a lower stage of the sheet ejection portion7. If the sheet P is guided to the conveyance path82directed to the upper stage of the sheet ejection portion7, the sheet P is ejected onto the upper stage of the sheet ejection portion7. Conversely, if the sheet P is guided to the conveyance path83directed to the lower stage of the sheet ejection portion7, a third path switch73selectively guides the sheet P to a conveyance path84directed to the lower stage of the sheet ejection portion7or a conveyance path85directed to the post-processing apparatus200.

If the sheet P is guided to the conveyance path84directed to the lower stage of the sheet ejection portion7, the sheet P is ejected onto the lower stage of the sheet ejection portion7. Conversely, if the sheet P is guided to the conveyance path85directed to the post-processing apparatus200, the sheet P is conveyed to the post-processing apparatus200where the sheet P is treated with post-processing.

Like the image forming apparatus100L depicted inFIG.25, the image forming apparatus100I illustrated inFIG.26, also serving as a liquid discharge apparatus, includes the original conveyance device1, the scanner2, the image forming device3, the sheet supply4, the cartridge holder5, the dryer6, the sheet ejection portion7, and the bypass sheet supply8. Like the image forming device3depicted inFIG.1, the image forming device3depicted inFIG.26is disposed opposite a conveyance path86extended in a horizontal direction inFIG.26such that a sheet P is conveyed in the horizontal direction through the conveyance path86.

When the image forming apparatus100M depicted inFIG.26receives an instruction to start a print job, the sheet supply4or the bypass sheet supply8supplies a sheet P that is conveyed to the image forming device3. When the sheet P reaches the image forming device3, the liquid discharge heads14discharge ink onto the sheet P, forming an image on the sheet P.

If the print job instructs duplex printing, after the sheet P passes the image forming device3, the sheet P is conveyed in an opposite direction. A first path switch74guides the sheet P to a reverse conveyance path87. The sheet P passes through the reverse conveyance path87and is conveyed to the image forming device3again in a state in which the sheet P is reversed. The image forming device3forms an image on the back side of the sheet P.

A second path switch75selectively guides the sheet P bearing the image on one side (e.g., the front side) or both sides (e.g., the front side and the back side) thereof to a conveyance path88directed to the dryer6or a conveyance path89directed to the post-processing apparatus200. If the sheet P is guided to the conveyance path88directed to the dryer6, the dryer6dries ink on the sheet P. The sheet P that has passed the dryer6is ejected onto the sheet ejection portion7. Conversely, if the sheet P is guided to the conveyance path89directed to the post-processing apparatus200, the sheet P is conveyed to the post-processing apparatus200where the sheet P is treated with post-processing.

Each of the image forming apparatus100L depicted inFIG.25and the image forming apparatus100I\4depicted inFIG.26is also applied with any one of the embodiments of the present disclosure, attaining advantages similar to the advantages described above. For example, a conveyance device (e.g., the conveyance devices40,40A,40AM,40B,40C,40D,40E,40F, and40G) installed in each of the image forming apparatuses100L and100M includes a ventilation device (e.g., the ventilation devices50,50A,50G,50H,50I,50J, and50K) that sends air to the sheet P. When the leading end of the sheet P passes through a blow region (e.g., the blow regions A, A1, and A2), the controller60controls the ventilation device to interrupt sending air or decrease the air capacity, preventing the air sent from the ventilation device from turning up or fluttering the sheet P.

The conveyance device according to any one of the embodiments of the present disclosure is installed in a body of an image forming apparatus (e.g., the image forming apparatuses100,100H,100I100J,100L, and100M). Alternatively, the conveyance device according to any one of the embodiments of the present disclosure may be applied to a conveyance device (e.g., a conveyance unit) that is removably attached to the body of the image forming apparatus.FIG.27illustrates an image forming apparatus100N, also serving as a liquid discharge apparatus, that includes a conveyance unit300to which any one of the embodiments of the present disclosure is applicable.

As illustrated inFIG.27, the conveyance unit300includes conveyance paths88and98that convey a sheet P bearing an image to the post-processing apparatus200(e.g., a sheet aligner). The conveyance unit300is removably installed in a body of the image forming apparatus100N, In the conveyance unit300also, if the conveyance unit300includes a ventilation device (e.g., the ventilation devices50,50A,50G,50H,50I,50J, and50K) that sends air to the sheet P, like in the embodiments described above, when the leading end of the sheet P passes through a blow region (e.g., the blow regions A, A1, and A2), the controller60controls the ventilation device to interrupt sending air from the ventilation device or decrease the air capacity, preventing the air sent from the ventilation device from turning up or fluttering the sheet P.

The conveyance device according to any one of the embodiments of the present disclosure is installed in an image forming apparatus (e.g., the image forming apparatuses100,100H,100I,100J,100L,100M, and100N), also serving as a liquid discharge apparatus, that forms an image on a sheet. Alternatively, the conveyance device according to any one of the embodiments of the present disclosure may be applied to a liquid discharge apparatus that discharges process liquid or the like not forming an image on a sheet.FIG.28illustrates a liquid discharge apparatus500to which any one of the embodiments of the present disclosure is applicable.

As illustrated inFIG.28, the liquid discharge apparatus500includes a process liquid discharger70serving as a liquid discharger that discharges process liquid that improves a surface of a sheet P before an image is formed on the sheet P. After the process liquid discharger70discharges the process liquid onto the sheet P, the sheet P is conveyed to an image forming apparatus100P. After the image forming device3of the image forming apparatus100P, also serving as a liquid discharge apparatus, discharges ink onto the sheet P, the sheet P is conveyed to the dryer6that dries the ink on the sheet P.

In a conveyance device (e.g., the conveyance devices40,40A,40AM,40B,40C,40D,40E,40F, and40G) installed in the liquid discharge apparatus500also, if the conveyance device includes a ventilation device (e.g., the ventilation devices50,50A,50G,50H,50I,50J, and50K) that sends air to the sheet P, like in the embodiments described above, when the leading end of the sheet P passes through a blow region (e.g., the blow regions A, A1, and A2), the controller60preferably controls the ventilation device to interrupt sending air from the ventilation device or decrease the air capacity, thus preventing the air from turning up or fluttering the sheet P.

Each of the embodiments of the present disclosure is also applicable to a post-processing apparatus that performs post-processing on a sheet bearing an image.FIG.29illustrates a post-processing apparatus400(e.g., a finisher) as an example of the post-processing apparatus to which any one of the embodiments of the present disclosure is applicable.

As illustrated inFIG.29, the post-processing apparatus400includes a post-processing device401that performs post-processing such as stapling and punching on a sheet P. When the sheet P is conveyed from the image forming apparatus100to the post-processing apparatus400depicted inFIG.29, a conveyance roller pair and the like convey the sheet P. Thereafter, the sheet P is placed on a mounting tray403of the post-processing device401. If the post-processing apparatus400employs a face-up manner system in which the sheets P are placed on the mounting tray403such that the image bearing face of each of the sheets P faces up, the sheets P are formed with images in an image formation order in which an image is formed on a last page of the sheets P first so that the last page of the sheets P is placed on the mounting tray403first. A conveyance roller402of the post-processing device401rotates forward to convey the sheet P placed on the mounting tray403backward. Accordingly, the trailing end of the sheet P strikes a trailing end restrictor403aof the mounting tray403. Thus, the trailing end restrictor403aaligns the trailing ends of the sheets P. In order to prevent the conveyance roller402from disturbing ejection of the sheets P onto the mounting tray403, the conveyance roller402moves from a contact position where the conveyance roller402contacts the sheet P to a retracted position where the conveyance roller402does not contact the sheet P. In a state in which the trailing ends of the sheets P are aligned, the post-processing device401performs post-processing such as stapling and punching on the sheets P. Thereafter, the conveyance roller402rotates backward to eject the sheets P placed on the mounting tray403to an outside of the post-processing apparatus400.

In a conveyance device (e.g., the conveyance devices40,40A,40AM,40B,40C,40D,40E,40F, and40G) installed in the post-processing apparatus400also, if the conveyance device includes a ventilation device (e.g., the ventilation devices50,50A,50G,50H,50I,50J, and50K) that sends air to the sheet P, like in the embodiments described above, when the leading end of the sheet P passes through a blow region (e.g., the blow regions A, A1, and A2), the controller60controls the ventilation device to interrupt sending air from the ventilation device or decrease the air capacity, preventing the air sent from the ventilation device from turning up or fluttering the sheet P.

According to the embodiments of the present disclosure, the sheets P include, in addition to plain paper, thick paper, thin paper, coated paper, a label sheet, and an envelope. The sheet P conveyed by the conveyance device according to any one of the embodiments of the present disclosure is not limited to a sheet made of paper. Alternatively, the sheet P may be a sheet made of resin, such as an overhead projector (OHP) transparency.

A description is provided of advantages of a conveyance device (e.g., the conveyance devices40,40A,40AM,40B,40C,40D,40E,40F, and40G).

As illustrated inFIG.2, the conveyance device includes a conveyor (e.g., the conveyance roller42and the conveyance belt44), a ventilator (e.g., the ventilators51,51A, and51K), and a controller (e.g., the controller60). The conveyor conveys a sheet (e.g., the sheet P). The ventilator sends air to the sheet conveyed by the conveyor in a predetermined region (e.g., the blow regions A, A1, and A2). At a time when a leading end of the sheet in a sheet conveyance direction (e.g., the sheet conveyance direction Y) is in the predetermined region and at a time when the leading end of the sheet in the sheet conveyance direction is past the predetermined region, the controller controls the ventilator to change an air capacity of the air sent from the ventilator.

Accordingly, the conveyance device prevents the air sent from the ventilator from turning up or fluttering the sheet, improving conveyance of the sheet.

According to the embodiments described above, the image forming apparatus100is a copier. Alternatively, the image forming apparatus100may be a printer, a facsimile machine, a multifunction peripheral (MFP) having at least two of printing, copying, facsimile, scanning, and plotter functions, an inkjet recording apparatus, or the like.