Image forming device

Information

  • Patent Grant
  • 6652091
  • Patent Number
    6,652,091
  • Date Filed
    Tuesday, April 30, 2002
    24 years ago
  • Date Issued
    Tuesday, November 25, 2003
    22 years ago
Abstract
A recording device includes a guide protruding from and retracting toward a platen and a discharge support protruding from and retracting toward the guide. With this arrangement, the process for fabricating the parts of the device is not complicated, a large space for the discharge support is not needed, and a required flatness of the upper surface of the platen is easily obtained even when the device includes the discharge support.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a recording device having a transport mechanism for transporting a recording medium such as a sheet of paper on which a recording head performs recording.




2. Description of the Related Art




In general, ink-jet recording devices perform recording on a recording medium by allowing a recording head to discharge flying ink drops. Such recording devices have various advantages such as an easy reduction in the size of the recording head, performing accurate and high-speed recording, a low running cost, low noise due to non-impact features, and easy forming of a color image by using a variety of color inks.




In such an ink-jet recording device, a recording sheet on which the recording head has performed recording is held by a platen in a recording area and is discharged by a discharge section disposed downstream in the transport direction of the recording sheet.




With reference to

FIGS. 14

to


17


, a known ink-jet recording device will be described.

FIG. 14

is a perspective view illustrating the overall structure of a known ink-jet recording device


1


.

FIG. 15

is a sectional view illustrating the overall structure of the known ink-jet recording device


1


.

FIG. 16

is a perspective view schematically illustrating the positional relationship among a transport roller, a pinch roller, spurs, discharge rollers and so forth in the known ink-jet recording device


1


.

FIG. 17

is a sectional view schematically illustrating the positional relationship among the spurs, discharge rollers and so forth in the known ink-jet recording device


1


.




As shown in

FIG. 15

, recording sheets P, as recording media, are stacked on a feeding section


2


and are fed sheet by sheet from the top of the stack by a feeding roller


22


. The recording sheet P fed by the feeding roller


22


is supported by a transport roller


36


and a pinch roller


37


while being sandwiched therebetween and is transported to the start point of recording on a platen


34


by the transport roller


36


which is driven by a drive source (not shown).




A recording head


7


is detachably mounted on a carriage


50


. The carriage


50


is movably mounted on a shaft


81


in a direction orthogonal to the transport direction of the recording sheet P. In other words, the recording head


7


performs recording while moving in a direction orthogonal to the transport direction of the recording sheet P.




A discharge roller shaft


41


is driven by a drive force of the transport roller


36


via a transmission roller


40


. As shown in

FIG. 16

, the discharge roller shaft


41


has a plurality of discharge rollers


41




a


made from elastomer or gum mounted thereon for transporting the recording sheet P. Spurs


42


press-contacting the corresponding discharge rollers


41




a


have a sharp-edged periphery in order to minimize an amount of ink of a recorded image transferred to the spurs


42


, since the spurs


42


come in contact with the recorded surface of the recording sheet P.




The recording sheet P is transported by the transport roller


36


and pinch roller


37


until the front end thereof is supported by the discharge rollers


41




a


and the spurs


42


while being sandwiched therebetween. After the rear end of the recording sheet P passes over the pinch roller


37


, the recording sheet P is transported by the discharge rollers


41




a


and the spurs


42


, and then is discharged and stored in a discharge tray


100


.




The platen


34


has a plurality of projected ribs


34




a


formed on the upper surface thereof along the transport direction of the recording sheet P and supports the plurality of spurs


42


, each disposed downstream of a corresponding projected rib


34




a


. Since the projected ribs


34




a


on the platen


34


and the corresponding spurs


42


are arranged on the same lines parallel to the transport direction of the recording sheet P in order to suppress the raised height of any cockled recording sheet P, wherein the cockling of the recording sheet P can occur when ink is applied on the recording sheet P, cockling having a concave shape is formed at every portion of the recording sheet between the adjacent projected ribs


34




a


, thereby minimizing the raised height of the cockled sheet lying in the recording area.




Such cockling is likely to occur especially when a permeable dye-type color ink is applied on the wide area of the recording sheet P. In the ink-jet recording device, the affect of the cockling must be eliminated and the gap between the recording sheet P and the recording head


7


must be maintained with the above arrangement in order to perform effective recording.




In recent years, a pigmentary black ink is used to increase black image density in the ink-jet recording device. The pigmentary ink requires a substantial time period for drying and fixing after the ink is applied on the recording sheet P. With this requirement, such pigmentary ink may cause a smear phenomenon in that a wet image formed on the previously discharged sheet is smeared by the currently discharging sheet because the front portion of the discharging sheet rubs the upper surface of the previously discharged sheet.




As shown in

FIG. 15

, a discharge section


4


of the recording device


1


has a discharge support


47


for preventing such smearing. The discharge support


47


supports the recording sheet that has been recorded, and extends the time period, from the applying time of ink on the recording sheet P to the arrival time of the recording sheet P at the discharge tray


100


, for drying the ink applied on the previously discharged sheet.




In the known recording device


1


, the platen


34


has the discharge support


47


that can be retracted therein. As shown in

FIG. 15

, the discharge support


47


usually retracts into the platen


34


, and is pulled out and protrudes from the platen


34


at the time of recording. A plurality of the discharge supports


47


is disposed between the adjacent spurs


42


.




While protruding from the platen


34


, all the discharge supports


47


guide the recording sheet P upward higher than the surface of the recording sheet P lying in the recording area and support the discharging sheet P so that it bends downwardly at its central portion under its own weight. The known recording device


1


provided with the discharge supports


47


extends the time period from the recording time to the arrival time of the recording sheet P at the discharge tray


100


.




However, in the known recording device


1


provided with the foregoing discharge supports


47


, some of the discharge supports


47


raise the cockling in the recording area, thereby causing the recording sheet P to form a convex shape instead of a concave shape of the cockling between the adjacent spurs


42


, and resulting in the substantially raised portions of the recording sheet P in the recording area. This causes the surface of the recording sheet P to come in contact with the recording head


7


or the carriage


50


, giving rise to problems such that the surface of the recording sheet gets dirty or the recording head


7


is damaged.




SUMMARY OF THE INVENTION




The present invention can provide a recording device, provided with a discharge support, in which the parts of the device are easily fabricated, a large space for the discharge support is not needed, and a required flatness of the upper surface of the platen is easily obtained.




The present invention can also provide a recording device that comprises (a) a recording head for performing recording on a recording medium, (b) a support for supporting the recording medium downstream from the recording head in the transport direction of the recording medium, (c) a guide for supporting the support and (d) a holder for holding the guide. The guide protrudes from and retracts toward the holder substantially in the transport direction of the recording medium, and the support protrudes from and retracts toward the guide in a direction different from the protruding direction of the guide.




Further objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view illustrating the overall structure of a recording device according to a first embodiment of the present invention.





FIG. 2

is a sectional view illustrating the overall structure of the recording device according to the first embodiment of the present invention.





FIG. 3

is another perspective view illustrating the overall structure of the recording device according to the first embodiment of the present invention.





FIG. 4

is a perspective view schematically illustrating the positional relationship among a transport roller, a pinch roller, spurs, discharge rollers and so forth of the recording device according to the first embodiment of the present invention.





FIG. 5

is a sectional view schematically illustrating the positional relationship among the spurs, the discharge rollers and so forth of the recording device according to the first embodiment of the present invention.





FIG. 6

is a perspective view illustrating a discharge section of the recording device viewed from the bottom thereof according to the first embodiment of the present invention.





FIG. 7

is a partially enlarged view of FIG.


6


.





FIG. 8

is a partially enlarged view illustrating a driving section for driving discharge supports of the recording device according to the first embodiment of the present invention.





FIG. 9

is an illustration of a state in which one of the discharge supports protrudes from a platen and supports a recording sheet.





FIG. 10

is an illustration of another state in which a recording sheet support portion as a downstream part of the discharge support lies at the lowest position and a guide protrudes from or retracts toward the platen.





FIG. 11

is an illustration of yet another state in which the guide has retracted toward the platen.





FIG. 12

is a sectional view illustrating the overall structure of a recording device according to a second embodiment of the present invention.





FIG. 13

is a sectional view illustrating the overall structure of a recording device according to a third embodiment of the present invention.





FIG. 14

is a perspective view illustrating the overall structure of a known ink-jet recording device.





FIG. 15

is a sectional view illustrating the overall structure of the known ink-jet recording device.





FIG. 16

is a perspective view schematically illustrating the positional relationship among a transport roller, a pinch roller, spurs, discharge rollers and so forth in the known ink-jet recording device.





FIG. 17

is a sectional view schematically illustrating the positional relationship among the spurs, discharge rollers and so forth in the known ink-jet recording device.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




With reference to the accompanying drawings, preferred embodiments of the present invention will be described.




First Embodiment




Referring to

FIGS. 1 and 2

, a recording device


101


according to a first embodiment of the present invention will be described. All the same parts are identified by the same reference numerals throughout the drawings.




As shown in

FIGS. 1 and 2

, the recording device


101


has a feeding section


2


, a transport section


3


, a discharge section


4


, a carriage section


5


, and a cleaning section


6


. Referring to

FIGS. 1 and 2

, first the feeding section


2


, the transport section


3


, the carriage section


5


, and the cleaning section


6


will be described in that order, and then the discharge section


4


, which characterizes the recording device


101


of the first embodiment, will be described in detail.




(1) Feeding Section




The feeding section


2


has a base


20


, a pressure plate


21


for stacking recording sheets P, and a feeding roller


22


for feeding each recording sheet P, the latter two being attached to the base


20


. The pressure plate


21


has a movable side guide


23


mounted thereon for adjusting the stacking position of the recording sheets P. The pressure plate


21


is connected to the base


20


rotatably about a shaft


38


and is urged to the feeding roller


22


via a pressure spring


24


. The pressure plate


21


has a separation pad


25


mounted on a portion thereof that opposes the feeding roller


22


, wherein the pad


25


is made from a material such as artificial leather having a large frictional coefficient for preventing double feeding of the recording sheets P.




In addition, the base


20


has a separation claw


26


for individually separating the recording sheets P, a mound


27


integrally formed therewith for separating media such as a pasteboard and the like, which are not readily separated by the separation claw


26


, a switching lever


28


for allowing the separation claw


26


to work at a normal paper position and for preventing it from working at a pasteboard position, and a release cam


29


for releasing the abutment between the pressure plate


21


and the feeding roller


22


.




When the recording device


101


is in a stand-by mode, the release cam


29


pushes the pressure plate


21


down to a predetermined position so that the abutment between the pressure plate


21


and the feeding roller


22


is released. When a drive force of a transport roller


36


is transmitted to the feeding roller


22


and the release cam


29


by a gear and the like in this mode, the release cam


29


detaches from the pressure plate


21


, allowing the pressure plate


21


to be elevated, thereby allowing the feeding roller


22


to abut against the recording sheet P. Then, rotation of the feeding roller


22


causes the recording sheet P to be picked up, and the feeding operation of the recording sheet P starts.




The fed recording sheets P are separated individually by the separation claw


26


and are transported to the transport section


3


. The feeding roller


22


and the release cam


29


rotate so as to complete transportation of the recording sheet P to the transport section


3


, and the recording device


101


returns to the stand-by mode in which the abutment between the recording sheet P and the feeding roller


22


is released and the drive force of the transport roller


36


is removed.




(2) Transport Section




The transport section


3


has the transport roller


36


for transporting the recording sheet P and a paper end sensor (hereinafter, abbreviated as a PE sensor)


32


. The transport roller


36


has an idle pinch roller


37


which abuts thereagainst and which is rotatably held by a pinch roller guide


30


. The pinch roller guide


30


is urged by a pinch roller spring


31


so as to press-contact the pinch roller


37


to the transport roller


36


, thus producing a transport force for transporting the recording sheet P.




The transport section


3


has an upper guide


33


for guiding the recording sheet P and a platen


34


disposed at the entrance thereof to which the recording sheet P is transported. The upper guide


33


has a PE sensor lever


35


thereon for informing the PE sensor


32


of a detection of a front end and a rear end of the recording sheet P.




With the foregoing configuration, the recording sheet P transported to the transport section


3


is conveyed to a pair of rollers consisting of the transport roller


36


and the pinch roller


37


, while being supported by the platen


34


and being guided by the pinch roller guide


30


, and the upper guide


33


. In this stage, the PE sensor


32


detects the front end of the transported-recording sheet P on the basis of information from the PE sensor lever


35


. The recording device


101


determines the location of a recording area of the detected-recording sheet P with respect to the detected front end.




The recording sheet P is transported onto the platen


34


by rotation of the pair of rollers


36


and


37


driven by a line feed motor (hereinafter, abbreviated as an LF motor) (not shown). A recording head


7


has an ink tank detachably mounted thereon and can apply heat to ink supplied from the ink tank using a heater and the like as an electricity-energy converter. The heat causes film-boiling of the ink in the recording head


7


, and the film-boiling causes a bubble to grow or shrink. As a result of a pressure change generated by the growth or shrinkage of the bubble, an ink drop is discharged from a nozzle of the recording head


7


, thereby forming an image on the recording sheet P.




(3) Carriage Section




The carriage section


5


has a carriage


50


on which the recording head


7


is mounted. The carriage


50


is supported by a guide shaft


81


for allowing the recording head


7


to scan back and forth in a direction orthogonal to the transport direction of the recording sheet P, and a guide rail


82


for maintaining the clearance between the recording head


7


and the recording sheet P by holding the rear end of the carriage


50


. The guide shaft


81


and the guide rail


82


are mounted on a chassis


8


.




The carriage


50


is driven by a carriage motor


80


mounted on the chassis


8


via a timing belt


83


. The timing belt


83


is stretched and supported by an idle pulley


84


. The carriage


50


has a flexible circuit board (not shown) mounted thereon for transmitting a recording signal from an electrical circuit board (not shown) in the recording device


101


to the recording head


7


. Attachment and detachment of the recording head


7


to and from the carriage


50


and of the ink tank to and from the recording head


7


are performed at a given position to which the carriage


50


moves when an operation key (not shown) is pressed.




With this configuration, when an image is to be formed on the recording sheet P, the pair of rollers


36


and


37


transports the recording sheet P to a line position where the image is to be formed (a position on a line in the transport direction of the recording sheet P), and the carriage motor


80


drives the carriage


50


to move to a row position where the image is to be formed (a position on another line orthogonal to the transport direction of the recording sheet P) such that the recording head


7


faces a position where the image is to be formed. Then, the recording head


7


discharges ink drops toward the recording sheet P in response to a recording signal received from the electrical circuit board and thereby forms the image.




(4) Cleaning Section




The cleaning section


6


has a pump


60


for cleaning the recording head


7


, a cap


61


for preventing the recording head


7


from drying, and a drive switching arm


62


for switching a drive force of the transport roller


36


to either one of the feeding section


2


and the pump


60


.




Since the drive switching arm


62


has a planetary gear (not shown) which rotates about the axial center of the transport roller


36


that is fixed at a predetermined position thereof, the drive force of the transport roller


36


is not transmitted to the feeding section


2


and the pump


60


when operations other than feeding and cleaning are performed in the recording device


101


.




When the drive switching arm


62


is moved in the direction of arrow A indicated in

FIG. 1

by movement of the carriage


50


, the planetary gear becomes free and moves in response to the normal rotation or reverse rotation of the transport roller


36


. That is to say, the drive force is transmitted to the feeding section


2


or the pump


60


when the transport roller


36


rotates normally or reversely, respectively.




(5) Discharge Section




The discharge section


4


has first and second discharge rollers


41




a


and


41


-


1




a


, a first transmission roller


40


abutting against the first discharge rollers


41




a


, and a second transmission roller


40


-


1


abutting against the second discharge rollers


41


-


1




a


. The drive force of the transport roller


36


is transmitted to the first discharge rollers


41




a


via the first transmission roller


40


and is then transmitted to the second discharge rollers


41


-


1




a


via the second transmission roller


40


-


1


. The first discharge rollers


41




a


have first spurs


42


abutting thereagainst and the second discharge rollers


41


-


1




a


have second spurs


42


-


1


abutting thereagainst, each arranged for rotation driven by the first discharge rollers


41




a


and the second discharge rollers


41


-


1




a


, respectively. The first and second spurs


42


and


42


-


1


have a cleaning roller


44


rotatably abutted thereagainst.




With the foregoing configuration, the recording sheet P, having the image formed thereon at the carriage section


5


, is transported while being interposed between a pair of the discharge rollers


41




a


and


41


-


1




a


and another pair of the spurs


42


and


42


-


1


, and then is discharged to a discharge tray


100


.




In addition, the second discharge rollers


41


-


1




a


have discharge supports


104


, for supporting the discharged recording sheet P, disposed downstream therefrom. The discharge supports


104


are rotatably attached to a guide


102


. The guide


102


protrudes from and retracts toward the platen


34


. The discharge supports


104


rotate in accordance with the linear motion of the guide


102


. The recording device


101


according to the first embodiment has five discharge supports


104


arranged in the width direction of the recording sheet P.




Referring now to

FIGS. 3

to


11


, the structure and operations of the discharge section


4


of the recording device


101


according to the first embodiment will be described.

FIG. 3

is a perspective view illustrating the overall structure of the recording device


101


.

FIG. 4

is a perspective view schematically illustrating the positional relationship among the transport roller


36


, the pinch roller


37


, the spurs


42


, the discharge rollers


41




a


and so forth of the recording device


101


.

FIG. 5

is a sectional view schematically illustrating the positional relationship among the spurs


42


, the discharge rollers


41




a


and so forth of the recording device


101


.

FIG. 6

is a perspective view illustrating the discharge section


4


of the recording device


101


viewed from the bottom thereof.

FIG. 7

is a partially enlarged view of FIG.


6


.

FIG. 8

is a partially enlarged view illustrating a driving section for driving the discharge supports


104


of the recording device


101


.

FIGS. 9

to


11


are sectional views of the discharge section


4


illustrating operations of the discharge section


4


of the recording device


101


.




As shown in

FIG. 3

, the platen


34


has a plurality of projected ribs


34




a


formed on the upper surface thereof extending along the transport direction of the recording sheet P and having a predetermined pitch in the width direction of the recording sheet P. The platen


34


has the first and second discharge rollers


41




a


and


41


-


1




a


downstream thereof arranged along the transport direction of the recording sheet P and in the width direction of the recording sheet P, each roller


41




a


and each roller


41


-


1




a


being aligned on the same line of the corresponding projected rib


34




a


. The second discharge rollers


41


-


1




a


have the corresponding discharge supports


104


downstream therefrom.




With the foregoing configuration, in a recording area, the recording sheet P is properly positioned away from the recording head


7


by the transport roller


36


and the pinch roller


37


and also by the first discharge rollers


41




a


and the first spurs


42


. Thus, a combination of the first discharge rollers


41




a


and the first spurs


42


and another combination of the second discharge rollers


41


-


1




a


and the second spurs


42


-


1


support the recording sheet P by sandwiching it therebetween and then discharge it.




In the recording device


101


, aligning each of the projected ribs


34




a


on the platen


34


, the corresponding first spur


42


, second spur


42


-


1


, and discharge support


104


substantially on the same line along the transport direction of the recording sheet P and aligning like components in the width direction of the recording sheet P allows the recording sheet P to form concave cockling at the time of recording between the adjacent projected ribs


34




a


.

FIG. 5

illustrates a state in which the concave cockling occurs at the time of recording between the adjacent projected ribs


34




a


on the platen


34


.




Next, the structure of the discharge supports


104


of the recording device


101


according to the first is embodiment will be described. The discharge supports


104


are supported by the guide


102


and a guide


103


and protrude from and retract toward the platen


34


. Once the discharge supports


104


have protruded from the platen


34


, the discharge supports


104


guide and support the recording sheet P upward from the horizontal surface on which a part of the recording sheet P lying in the recording area is supported.




The recording sheet P of A-4 size is supported by the discharge supports


104


-


1


to


104


-


3


and the recording sheet P of A-3 size is supported by all the discharge supports


104


-


1


to


104


-


5


. The discharge supports


104


support the recording sheet P so that the central portion of the recording sheet P warps downward under its own weight. In the recording device


101


, the discharge supports


104


-


1


and


104


-


5


have the same shape, and the discharge supports


104


-


2


and


104


-


4


have the other same shape, taking the A-3 size width as a basic structure.




In a state in which the discharge supports


104


protrude from the platen


34


, the downstream highest portions, i.e., the recording sheet support portions, of the discharge supports


104


-


1


and


104


-


5


are higher than those of the discharge supports


104


-


2


and


104


-


4


. Also, the recording sheet P of A-4 size is supported by the discharge supports


104


-


1


to


104


-


3


as described above, and the downstream highest portion of the discharge support


104


-


3


is slightly higher than that of the discharge support


104


-


2


.




In the recording device


101


, when moderate density recording is performed on the recording sheet P of A-3 size, the recording sheet P is supported by the discharge supports


104


-


1


,


104


-


3


, and


104


-


5


. When high print density recording is performed on the above recording sheet P, the recording sheet P is also supported by the discharge supports


104


-


2


and


104


-


4


so as to prevent it from becoming buckled and thereby jackknifed between the discharge supports


104


-


1


and


104


-


5


. In this embodiment, the downstream highest portion of the discharge support


104


-


3


is set to be higher than those of the discharge supports


104


-


2


and


104


-


4


; however, it may be as high as or lower than those of the discharge supports


104


-


2


and


104


-


4


.




As shown in

FIG. 9

, the discharge supports


104


-


1


and


104


-


2


are supported by the guide


102


in a rotatable manner about a shaft


102




c


of the guide


102


. Likewise, the discharge supports


104


-


3


to


104


-


5


are supported by the guide


103


in a rotatable manner about a shaft (not shown) of the guide


103


.




The recording sheet support portions


104




b


of the discharge supports


104


have a gradual upward-canted shape toward their downstream ends. After the front end of the recording sheet P that has been recorded abuts against the recording sheet support portions


104




b


, the recording sheet P is supported by the recording sheet support portions


104




b


and thus is transported smoothly. Also, each of the discharge supports


104


has a cam crest


104




a


at its upstream end for determining a vertical position of the recording sheet support portion


104




b


at its downstream end by abutting against cam rails


341


to


344


of the platen


34


that will be described later. Furthermore, each of the discharge supports


104


has a boss


104




c


at the underside of its upstream end. As shown in

FIGS. 10 and 11

, each of the discharge supports


104


and the guide


102


have a spring


114


inserted therebetween so that the cam crest


104




a


abuts against the cam rails


341


to


344


all the time.




As shown in

FIG. 8

, the guide


103


has guide rails


103




c


on both sides thereof abutting against guide grooves


34




c


disposed on the platen


34


. The guide


103


protrudes from and retracts toward the platen


34


by its guide rails


103




c


slideably and linearly moving along the guide grooves


34




c


of the platen


34


. Likewise, the guide


102


protrudes from and retracts toward the platen


34


by slideably and linearly moving along guide rail


102




b


and the guide grove


34




c


of the platen


34


(FIG.


6


). As shown in

FIGS. 6 and 7

, the guide


103


has two projected guide rails


103




c


thereon, engaging with the respective guide grooves


34




c


of the platen


34


.




Also, the guide


102


has a rack


102




a


at the bottom thereof and the guide


103


has two racks


103




a


and


103




b


at the bottom thereof. The platen


34


has a drive shaft


109


rotatably supported by a bearing


34




b


disposed on the platen


34


. Engaging pinion gears


109




a


,


109




b


, and


109




c


provided on the drive shaft


109


with the racks


102




a


,


103




a


, and


103




b


, respectively, of the guides


102


and


103


allows the guides


102


and


103


to move.




With the foregoing configuration, the guides


102


and


103


move linearly so as to protrude from and retract toward the platen


34


by a rotation of the drive shaft


109


. The guides


102


and


103


are positioned in desired positions (not shown) when protruding from the platen


34


.




The drive shaft


109


has a gear


109




d


disposed at one end thereof. Transmission gears


110


and


111


are rotatably supported by a bearing


34




d


(

FIG. 7

) disposed on the platen


34


. The transmission gear


111


is coaxially arranged with the transmission gear


110


and engages with a motor gear


113


of a motor


112


. The transmission gears


110


and


111


have a torque limiter (not shown) therebetween urged by a spring (not shown). This arrangement avoids cog slip between the pinion gears


109




a


,


109




b


, and


109




c


and the respectively corresponding racks


102




a


,


103




a


, and


103




b


, when the guides


102


and


103


are driven by the motor


112


and then stop upon bumping into predetermined points of the platen


34


.




Operations of the discharge supports


104


will now be described. In the recording device


101


, the discharge supports


104


are controlled so as to extrude prior to the start of recording by the recording head and retract upon a discharging operation of the recording sheet P after completion of recording.




In the recording device


101


according to the first embodiment, the motor


112


drives the motor gear


113


for rotation, allowing the drive force thereof to be transmitted to the transmission gear


111


and then to the drive shaft


109


via the transmission gear


110


and the gear


109




d


for rotation of the drive shaft


109


. The guides


102


and


103


move linearly by engagement of the pinion gears


109




a


to


109




c


provided on the drive shaft


109


with the corresponding racks


102




a


,


103




a


, and


103




b


, respectively. The discharge supports


104


protrude from and retract toward the guides


102


and


103


in response to the movements of the guides


102


and


103


.





FIG. 9

illustrates a state in which the discharge support


104


protrudes from the platen


34


and supports the recording sheet P.

FIG. 10

illustrates a state in which the recording sheet support portion


104




b


at the downstream end of the discharge support


104


lies at its lowest point and the guide


102


is protruding from or retracting toward or into the platen


34


.

FIG. 11

illustrates a state in which the guide


102


has retracted into the platen


34


.




As shown in

FIG. 11

, when the guide


102


retracts toward the platen


34


, the discharge support


104


has retracted to the guide


102


. In this stage, the cam crest


104




a


has abutted against the cam rail


344


of the platen


34


urged by the spring


114


.




As shown in

FIG. 10

, rotation of the pinion gear


109




a


of the drive shaft


109


allows the rack


102




a


engaging with the pinion gear


109




a


to move and thereby the guide


102


to start protruding. The cam crest


104




a


of the discharge support


104


slides along the cam rails


344


and


343


of the platen


34


against the force of the spring


114


.




When the recording sheet support portion


104




b


of the discharge support


104


passes the second discharge roller


41


-


1




a


and the cam crest


104




a


abuts against a sloped cam rail


342


, the cam crest


104




a


is lowered and the recording sheet support portion


104




b


of the discharge support


104


is gradually raised. Then, as shown in

FIG. 9

, the recording sheet support portion


104




b


reaches its highest position while the cam crest


104




a


abuts against the lowest surface of the cam rail


341


. The guide


102


bumps into a predetermined point of the platen


34


and stops, allowing the recording sheet support portion


104




b


of the discharge supports


104


to be held at a predetermined point. After the front end of the recording sheet P passes the second spur


42


-


1


, the recording sheet P abuts against the slope of the discharge support


104


, is transported along the slope, and is supported by the downstream lowest point of the discharge support


104


.




Timing for protrusion and retraction of the discharge supports


104


and the guides


102


and


103


is controlled by control means (not shown) on the basis of sizes of the recording sheets P, timing for recording in the recording area, and so forth.




Although the recording device


101


according to the first embodiment initiates protrusion of the discharge supports


104


before the recording head


7


starts recording, the recording device


101


may initiate protrusion of the discharge supports


104


during recording as long as the protrusion does not affect the recorded image.




When a thick special sheet such as a pasteboard, on which high quality recording is required and which has little potential for cockling, is used as a recording medium, high stiffness of the sheet itself has a negative effect on the angle of the sheet around the recording area thereof because of the slope of the discharge supports


104


. Therefore, in this case, the recording device


101


may control recording and discharging of the recording sheet P without the discharge supports


104


protruding from the platen


34


.




Also, though the recording device


101


according to the first embodiment has the guides


102


and


103


facing the recording head


7


so as to protrude from and retract toward the platen


34


for supporting the recording sheet P, the recording device


101


may be provided with a special holder (not shown) downstream thereof, in addition to the platen


34


, for holding the guides


102


and


103


, and may be configured such that the guides


102


and


103


protrude from and retract toward the holder.




According to the first embodiment, since each of the projected ribs


34




a


on the platen


34


, the corresponding first spur


42


and first discharge roller


41




a


are aligned on the same line along the transport direction of the recording sheet P and like components are aligned in the width direction of the recording sheet P, the shape of any generated cockling is not affected by the discharge supports


104


. Also, the guides are provided so as to protrude from and retract toward the platen, and the discharge supports are provided so as to protrude from and retract toward the guides, thereby providing discharge supports without employing a complicated mechanism.




Second Embodiment




A recording device according to a second embodiment of the present invention will be described.

FIG. 12

is a sectional view illustrating the configuration of a recording device


1101


according to the second embodiment. As shown in

FIG. 12

, the discharge roller and the spur are disposed in a row, making the device of the second embodiment different from that of the first embodiment.




In the recording device


1101


, a drive force of the transport roller


36


is transmitted to the discharge roller


41




a


via the transmission roller


40


at the discharge section


4


. The discharge support


104


is disposed on the same line with the spur


42


along the transport direction of the recording sheet P and two or more discharge supports are disposed across the width direction of the recording sheet P. Operations of the recording device


1101


are the same as those of the recording device


101


.




According to the second embodiment, the recording device


1101


having a set of the discharge roller


41




a


and the spur


42


which are disposed in a row requires a further smaller space for the discharge support


104


than that of the recording device


101


according to the first embodiment.




Third Embodiment




A recording device according to a third embodiment of the present invention will be described.

FIG. 13

is a sectional view illustrating the configuration of a recording device


2101


according to the third embodiment. As shown in

FIG. 13

, the recording device


2101


has a roller


120


rotatably mounted at a downstream portion of the discharge support


104


. Supporting the recording sheet P by the roller


120


leads to reduction in the friction caused by transporting the recording sheet P. Operations of the recording device


2101


are the same as those of the recording device


101


.




According to the third embodiment, the recording device


2101


having a roller


120


at a downstream portion of the discharge support


104


accurately transports the recording sheet P, thereby providing a high-quality recorded image.




The foregoing discharge support mechanism is applicable to a recording device provided with a recording head employing an electrothermal converter or a piezo-electric element. One skilled in the art will appreciate that the discharge mechanism is also applicable to a recording device provided with a recording head other than an ink-jet type.




In the recording device according to the third embodiment, the guide protrudes from and retracts toward the platen and the discharge support protrudes from and retracts toward the guide, providing the discharge support without employing a complicated mechanism. This configuration allows the discharge support to move in a smaller working area when the discharge support is aligned substantially on the same line with the discharge roller or the spur along the transport direction of the recording sheet, with two or more discharge supports disposed across the width direction of the recording sheet.




The smaller working area of the discharge support increases the strength of the platen, making it easy to achieve a required flatness of each rib formed on the upper surface of the platen, thereby leading to maintaining a certain amount of gap between the recording head and the recording sheet P.




While the present invention has been described with reference to what are presently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.



Claims
  • 1. A recording apparatus for recording on a recording medium with a recording head, said recording apparatus comprising:a platen for supporting the recording medium at a position facing the recording head; a guide capable of protruding from and retracting toward said platen in the transport direction of the recording medium; and a discharge support capable of protruding from and retracting toward said guide in a different direction from a protruding direction of said guide, wherein said discharge support supports the recording medium when the recording medium recorded by the recording head is discharged outside of said recording apparatus.
  • 2. The recording apparatus according to claim 1, wherein said discharge support is rotatable relative to said guide and protrudes from and retracts toward said guide in accordance with movement of said guide protruding from and retracting toward said platen.
  • 3. The recording apparatus according to claim 1,wherein said discharge support comprises a recording medium support portion, and wherein said recording medium support portion is disposed closer to said recording head than a support surface of the recording medium, the support surface being supported in the recording region, when said discharge support is in a protruded position, and said support surface is disposed farther from the recording head than the support surface when said discharge support is in a retracted position.
  • 4. The recording apparatus according to claim 1, further comprising control means for controlling said guide and said discharge support, wherein said control means controls said guide and said discharge support in response to a transport location of the recording medium.
  • 5. The recording apparatus according to claim 4, wherein said control means controls said guide and said discharge support to protrude before said recording head starts recording on the recording medium or while said recording head is performing recording on the recording medium, and said control means controls said guide and said discharge support to retract after said recording head completes recording on the recording medium or while said recording head is not performing recording on the recording medium.
  • 6. The recording apparatus according to claim 1, wherein said discharge support comprises a plurality of discharge support units arranged in a width direction of the recording medium so as to support both sides of at least one standard recording medium.
  • 7. The recording apparatus according to claim 6, wherein when protruded, said discharge support supports an outer portion of the recording medium at a position higher than the central portion of the recording medium.
  • 8. The recording apparatus according to claim 1, further comprising a discharge roller for transporting the recording medium, wherein said discharge support is aligned substantially on the same line as said discharge roller along the transport direction of the recording medium.
  • 9. The recording apparatus according to claim 1, wherein the recording head is an ink-jet recording head for discharging ink.
  • 10. The recording apparatus according to claim 9, wherein said ink-jet recording head comprises an electrothermal converter for generating heat to be applied to the ink to eject the ink.
  • 11. The recording apparatus according to claim 1, wherein said guide is driven by a rack and gear mechanism.
  • 12. The recording apparatus according to claim 1, wherein said discharge support is driven by a cam and follower mechanism.
  • 13. The recording apparatus according to claim 1, wherein movement of said discharge support is interrelated with movement of said guide.
  • 14. A recording device comprising:recording means for performing recording on a recording medium; support means for supporting the recording medium downstream from said recording means in the transport direction of the recording medium; guide means for supporting said support means; and holding means for holding said guide means, wherein said guide means protrudes from and retracts toward said holding means substantially in the transport direction of the recording medium, and said support means protrudes from and retracts toward said guide means in a direction different from the protruding direction of said guide means.
  • 15. The recording device according to claim 14, wherein said support means supports the recording medium that is discharged from a recording region.
  • 16. The recording device according to claim 14, further comprising control means for controlling said guide means and said support means, wherein said control means controls said guide means and said support means in response to a transport location of the recording medium.
  • 17. The recording device according to claim 16, wherein said control means controls said guide means and said support means to protrude before said recording means starts recording on the recording medium or while said recording means is performing recording on the recording medium, and said control means controls said guide means and said discharge support means to retract after said recording means completes recording on the recording medium or while said recording means is not performing recording on the recording medium.
  • 18. The recording device according to claim 14, wherein said support means supports an outer portion of the recording medium in a position higher than the central portion of the recording medium.
Priority Claims (1)
Number Date Country Kind
2001-139895 May 2001 JP
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