JP4055450B2 - Recording medium discharging apparatus, discharging method, conveying apparatus, and ink jet recording apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording medium discharging apparatus, a discharging method, a conveying apparatus, and an ink jet recording apparatus including the discharging apparatus or conveying apparatus.
[0002]
[Prior art]
FIG. 10 is a side view showing an internal configuration example of an ink jet printer which is one of general ink jet recording apparatuses. This ink jet printer includes a paper feed roller 1 and a hopper 2 as automatic continuous paper feeding means (automatic sheet feeder), and a paper feed roller 3, a driven roller 4, a transport stage 5, a paper discharge roller 6 and a toothed tooth as transport means. It includes a roller (paper discharge serration) 7 and a carriage 8 and a recording head 9 as recording means.
[0003]
The ink jet printer having such a configuration supplies, for example, paper as a recording medium by the automatic continuous paper feeding means, and ejects ink droplets onto the paper by the recording means while transporting the paper by the transport means. Is to be printed. In other words, the control unit of the ink jet printer rotates the paper feed roller 1 to raise the hopper 2, thereby pressing a plurality of sheets P stacked on the hopper 2 against the paper feed roller 1, and the uppermost paper P Are separated from the lower sheet P and fed. Then, the paper P is sandwiched between the paper feed roller 3 and the driven roller 4, and the paper feed roller 3 is rotated and sent out onto the transport stage 5.
[0004]
Subsequently, for example, each color ink is supplied from a total of four color ink cartridges of yellow, magenta, cyan, and black to the pressure generation chamber of the recording head 9 mounted on the carriage 8, and the ink in the pressure generation chamber is pressurized to open the nozzles. Ink droplets are ejected from the paper toward the paper P. At this time, the ejection timing of each color ink and the driving of the carriage 8 and the paper feed roller 3 are controlled to execute highly accurate ink dot control, halftone processing, and the like. Then, the paper P is sandwiched between the paper discharge roller 6 and the paper discharge jaw 7, and the paper discharge roller 6 is rotated and sent out onto a paper discharge stacker (not shown) for discharge.
[0005]
[Problems to be solved by the invention]
In the above-described ink jet printer, the discharge roller 6 disposed on the discharge side of the paper P is formed of rubber, and the discharge jaw 7 is formed in a saw blade shape at the peripheral edge. The paper P is fed out by friction and the paper discharge serration 7 biting into the paper P. For this reason, it is possible to prevent the paper P from being swelled when the paper P is sent out and to smoothly discharge the paper P. However, when the paper P has traces of the paper discharge serrations 7 or printing rubbing occurs. There is.
[0006]
The present invention has been made in view of the various problems as described above, and an object of the present invention is to provide a recording medium discharging apparatus, a discharging method, a conveying apparatus, and a discharging apparatus capable of discharging the recording medium in a good state. Another object of the present invention is to provide an ink jet recording apparatus including a transport device.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the recording medium transport apparatus according to the claims of the present invention, an operation of sucking a recording medium to be fed and an operation of reciprocating in the feeding direction of the recording medium are possible. A recording medium conveying apparatus having a stage that conveys the recording medium by performing an appropriate combination and a suction unit that sucks air to suck the recording medium, and the recording on the stage moved to a medium discharge position An exhaust port that blows out an airflow for discharging the medium is disposed below the stage, and a communication port that communicates the stage and the suction unit is disposed, and the communication port is moved by the movement of the stage. The exposure is characterized in that the flow rate of the discharged airflow at the medium discharge position is increased.
[0008]
As a result, the recording medium discharge roller or the like can be dispensed with, so that the recording medium can be discharged in a good state without scars or ink rubbing.
[0009]
Further, when the stage is moved to the recording medium discharge position, the communication port is opened so that the flow path load can be reduced, so that the amount of air exhausted by reducing the suction force that adsorbs the recording medium. The recording medium can be reliably discharged.
[0010]
In the recording medium conveying apparatus according to the present invention, the air flow for discharging the recording medium uses air discharged from the suction means when the recording medium is sucked by the stage. It is said.
[0011]
In the recording medium transport apparatus according to the claims of the present invention, when the recording medium is discharged, an air flow having a larger flow rate than that during recording is generated.
[0012]
In order to achieve the above object, the invention according to the claims of the present invention is characterized in that an ink jet recording apparatus for recording by ejecting ink onto a transported recording medium is provided with each of the recording medium transport apparatuses. .
[0013]
Thereby, an ink jet recording apparatus that exhibits the above-described effects can be provided.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
FIG. 1 is a side view showing an internal configuration example of an ink jet printer which is one of ink jet recording apparatuses according to an embodiment of the present invention. This ink jet printer includes a sheet feeding roller 11 and a hopper 12 as automatic continuous sheet feeding means (auto sheet feeder), and includes a paper feed roller 13, a driven roller 14, a conveying stage 50, and a main body 60 as conveying means, and recording. A carriage 18 and a recording head 19 are provided as means.
[0016]
The ink jet printer supplies a recording medium such as paper P by an automatic continuous paper feeding means, and prints characters, images, etc. by ejecting ink droplets onto the paper P by the recording means while transporting the paper P by the transport means. It is supposed to be. Hereinafter, the conveyance direction of the paper P indicated by the illustrated arrow is referred to as F direction, and the scanning direction of the recording head 19 is referred to as S direction.
[0017]
FIG. 2 is a perspective view showing a detailed example of the transfer stage 50 and the main body 60, and FIG. 3 is a plan view thereof. Hereinafter, the conveyance stage 50 and the main body 60 will be described with reference to FIGS. The conveyance stage 50 formed in the shape of a rectangular flat plate is engaged with guide shafts 55 that are attached so that the engaging portions 51 formed at both ends in the S direction extend in the F direction at both ends in the S direction of the main body 60. Further, it is engaged with a toothed belt 56a constituting a belt drive mechanism 56 disposed on both sides of the main body 60 in the S direction. The transport stage 50 moves in the F direction along the guide shaft 55 on the upper surface of the main body 60 by the rotation of the toothed pulley 56b and the toothed belt 56a constituting the belt driving mechanism 56.
[0018]
On the upper surface of the transport stage 50, suction portions 52a and 52b that suck air to suck the paper P, and an ink receiving portion that receives ink to be discarded from the nozzles of the recording head 19 when printing without a margin at the upper end of the paper P. 53 is formed. A plurality of suction portions 52a and 52b are formed side by side in the S direction as quadrangular pyramid-shaped recesses. The ink receiving portion 53 is formed as a triangular prism-shaped concave portion so as to extend one in the S direction.
[0019]
Through holes 52aa, 52ba, and 53a are perforated at the bottoms of the suction portions 52a and 52b and the ink receiving portion 53. Thereby, even when an ink absorbing material is installed in the ink receiving portion 53, the air passes through the through hole 53a, so that the ink absorbing material can be dried in a short time. Further, in this example, two rows of suction portions 52a are formed from the downstream side in the F direction toward the upstream side in the F direction, the ink receiving portion 53 is subsequently formed, and the suction portion 52b is further formed. Yes. The suction part 52b on the most upstream side is formed especially for adsorbing the upper and lower ends of the paper P.
[0020]
A plurality of support portions 54 that support the lower end of the paper P are disposed at a rear portion of the transport stage 50 at a predetermined interval. The support portion 54 is configured by a lever 54a whose one end is rotatably locked in a groove provided in the rear portion of the transfer stage 50, and a torsion coil spring (not shown) that urges the lever 54a in the rotation direction. Has been. The lever 54a of the support part 54 protrudes from the rear part of the transport stage 50 by the restoring force of the torsion coil spring when the rear part of the transport stage 50 is separated from the stopper 61 attached to the rear part of the upper surface of the main body part 60. ing.
[0021]
When the rear part of the transfer stage 50 approaches the stopper 61 attached to the upper surface of the rear part of the main body part 60, it is pushed into the groove at the rear part of the transfer stage 50 and stored against the restoring force of the torsion coil spring. It is like that. In this example, the lever 54a of the support portion 54 is attached so as to be rotatable. However, the lever 54a may be attached so as to be linearly movable using, for example, a compression coil spring.
[0022]
The main body 60 is formed with two layers of hollow portions in the vertical direction. A communication port 63 that communicates with the upper layer hollow portion is perforated on the upper surface of the main body portion 60, and a communication port 64 that communicates the upper layer hollow portion with the lower layer hollow portion at the boundary surface between the two hollow portions of the main body portion 60. And an exhaust port 65 communicating with the lower hollow portion is formed in the front surface of the main body 60. The communication port 63 is formed in a rectangular shape at a position that is opened when the transport stage 50 moves to the discharge position of the paper P on the front side of the main body 60. The communication port 64 is formed in a circular shape at a position almost directly below the communication port 63. The exhaust port 65 has a rectangular shape having at least the width of the paper P, and is formed so that the flow passage area from the lower hollow portion to the exhaust port 65 gradually decreases, and the exhaust is directed obliquely upward.
[0023]
An intake fan 66 is disposed in the lower hollow portion of the main body 60. Thus, the upper hollow portion of the main body 60 serves as a decompression chamber 67 that applies a negative pressure to the suction portions 52a and 52b and the ink receiving portion 53 through the through holes 52aa, 52ba, and 53a formed in the transport stage 50. Function. The lower hollow portion of the main body 60 functions as an exhaust chamber 68 that exhausts air that has been sucked from the through holes 52aa, 52ba, and 53a formed in the transfer stage 50 through the upper hollow portion from the exhaust port 65.
[0024]
Furthermore, an ink receiving portion 69 that receives ink that is discarded from the nozzles of the recording head 19 when the lower end margin printing of the paper P is performed is formed on the upper surface of the main body portion 60. The ink receiving portion 69 is located upstream of the communication port 63 in the F direction, and is exposed as a quadrangular columnar concave portion in the S direction at a position exposed when the transport stage 50 moves to the front side of the main body portion 60. It is formed to extend. Note that an ink absorbing material may be disposed inside the ink receiving portion 69.
[0025]
In such a configuration, an example of the operation will be described with reference to the flowchart of FIG. 4 and the operation diagrams of FIGS. The control unit of the ink jet printer rotates the paper feed roller 11 to raise the hopper 12, thereby pressing a plurality of sheets P stacked on the hopper 12 against the paper feed roller 11 and lowering the uppermost paper P to the lower order. The paper P is separated and fed.
[0026]
Subsequently, the paper P is sandwiched between the paper feed roller 13 and the driven roller 14, and the paper feed roller 13 is rotated and sent out onto the transport stage 50. At this time, as shown in FIG. 5A, the transport stage 50 is positioned at the home position where the lever 54 a of the support portion 54 contacts the stopper 61 of the main body portion 60 and is stored. This home position is a predetermined distance after the transfer stage 50 is moved to the rear side of the main body 60 and the flag passes through a stage detector that detects the front side of the transfer stage 50, for example, 120 inches of 180/180. The moved position.
[0027]
Then, cueing of the paper P is performed. Specifically, the upper end of the paper P used for printing in the first pass shown in FIG. 5B, that is, the position before the first raster position when the upper end of the paper P is printed at the normal paper feed amount. The paper P is transported so as to be located at a distance d away from the first raster nozzle #n, which is a nozzle, toward the rear side of the transport stage 50 (step S1).
[0028]
At the same time, the conveyance stage 50 is set at the print start position. Specifically, the transport stage 50 is moved so that the top of the ink receiving portion 53 that is a V-shaped groove formed in the transport stage 50 is located at a position facing the first raster nozzle #n (step S2). At this time, the upper end of the paper P is attracted to the suction portion 52b and flattened, so that a stable paper gap can be secured to improve the printing image quality, and the recording of the paper P with reduced floating. Contamination due to rubbing with the head 19 can be prevented.
[0029]
Next, printing without an upper margin is started. That is, the paper feed roller 13 is rotated so that the normal paper feed amount is obtained, and the top portion of the ink receiving portion 53 is always opposed to the first raster nozzle #n so as to be removed from the upper end of the paper P and discarded. The transport stage 50 is moved to the front side of the main body 60 in synchronism with the rotation of the paper feed roller 13 so that the ink receiver 53 can reliably receive the droplets (step S3). At this time, the ink received by the ink receiving portion 53 is not accumulated inside but is discharged to the outside from the through hole 53a, so that the contamination of the paper P by the ink is reduced as compared with the case where the ink is simply absorbed by the ink absorbing material. In addition, the number of maintenance steps such as replacement of the ink absorbing material can be reduced.
[0030]
For example, as shown in FIG. 9, this top marginless printing is performed when the nozzle interval of the recording head 19 is 4, the number of nozzles is 11, and the feed amount is 11, and the nozzles # 8 to # 11 are used in the first pass. Printing without upper margin is performed by the ejected ink droplets, and the ink droplets ejected from the nozzles # 1 to # 7 are discarded by the ink receiving portion 53, and ejected from the nozzles # 5 to # 11 in the second pass. The upper end margin printing is performed by the ink droplets, and the ink droplets ejected from the nozzles # 1 to # 4 are discarded by the ink receiving portion 53. Further, in the third pass, printing without upper margin is performed by the ink droplets ejected from the nozzles # 3 to # 11, and the ink droplet ejected from the nozzles # 1 to # 2 is discarded by the ink receiving portion 53. In the fourth and subsequent passes, printing without upper margin is performed by ink droplets ejected from all nozzles.
[0031]
Then, as shown in FIGS. 6A and 6B, when the flag of the transport stage 50 passes through the stage detector that detects the rear side of the side surface of the transport stage 50 (step S4), the paper feed roller 13 is moved to the normal paper. The printing operation is continued as it is by rotating it to the feed amount, and as shown in FIG. 7A, only the transport stage 50 is moved to the rear side of the main body 60 to return to the home position (step S5). . Accordingly, since the upper end to the lower end of the paper P can be supported on the transport stage 50, a stable paper gap can be secured over the entire surface of the paper P, and the print image quality can be improved.
[0032]
Next, when the paper detector 15 detects the lower end of the paper P while the printing operation continues (steps S6 and S7), printing without a lower end margin is started. That is, when the paper detector 15 detects the lower end of the paper P, the transport stage 50 starts to move to the front side of the main body 60 with the same movement amount as the normal paper feed amount by the paper feed roller 13 (step S8). ). Accordingly, since the transfer from the transport of the paper P by the paper feed roller 13 to the transport of the paper P by the transport stage 50 can be performed smoothly, the print image quality of the entire surface of the paper P can be improved. At this time, the synchronization of the feeding speed of the paper P by the transport stage 50 and the feeding speed of the paper P by the paper feeding roller 13 is absorbed by the slip of the paper P, and therefore it is not necessary to take it.
[0033]
Then, as shown in FIG. 7B, when the lower end of the paper P is detached from the paper feed roller 13, the paper P is sucked and held on the transport stage 50 and transported. At this time, the lower end of the paper P on the transport stage 50 is attracted and flattened by the suction portion 52b, and the lower end of the paper P protruding from the rear end of the transport stage 50 is supported by the support portion 54. Since it does not drop even if it is pulled downward due to the suction air flow that adsorbs the paper P, it can improve the print image quality by securing a stable paper gap and reduce the floating of the paper P Contamination due to rubbing with the recording head 19 can be prevented. When the transport stage 50 moves, the ink receiving portion 69 of the main body 60 is exposed, so that the ink receiving portion 69 receives ink droplets that are removed from the lower end of the paper P and discarded.
[0034]
When the print data is completed (step S9), the paper P is discharged. That is, when the print data is completed, as shown in FIG. 8, the transport stage 50 is continuously driven and moved to the paper discharge position (step S10). This discharge position is a predetermined distance, for example, 28/180, after the flag passes the stage detector that detects the rear side of the side surface of the transport stage 50 when the transport stage 50 is moved to the front side of the main body 60. The position moved by inches.
[0035]
When the transport stage 50 moves to the paper discharge position, a part of the communication port 63 is opened and the suction force of the suction parts 52a and 52b is reduced, and at the same time, the exhaust amount of the paper discharge port 65 is increased. For this reason, the paper P that has been adsorbed on the transport stage 50 is pushed out onto a paper discharge stacker (not shown) by the air blown from the paper discharge port 65 (step S11). This eliminates the need for a discharge roller or the like for the paper P, so that the paper P can be discharged in a good state without scars or ink rubbing. Thereafter, the transport stage 50 is moved to the rear side of the main body 60 to return to the home position (step S12), and the printing process is terminated.
[0036]
As described above, since the conveyance stage 50 is connected to the belt driving mechanism 62 and has the suction portions 52a and 52b, the upper end and the lower end of the paper P are attracted onto the conveyance stage 50 to convey the paper P. It can be transported by moving the stage 50. In addition, since the ink receiving portion 69 for printing without a lower margin is formed in the main body portion 60, only one ink receiving portion 53 for printing without a margin at the upper end may be provided on the transport stage 50.
[0037]
Therefore, it is not necessary to provide the ribs, which have been conventionally required for securing the paper gap and reducing the conveyance resistance, on the conveyance stage 50, so that the problems described in the related art can be solved. For this reason, printing without upper and lower margins can be performed at a normal printing speed using all nozzles in the same way as normal printing, so that the printing work time can be shortened and the printing portion without upper and lower margins can be reduced. It is possible to improve the print image quality on the entire surface of the paper by eliminating the boundary with the print portion.
[0038]
In the above-described embodiment, the planar shape of the ink receiving portion 53 formed on the transport stage 50 is a rectangular shape. However, when the transport stage 50 returns to the home position, the end portion of the paper P becomes the ink receiving portion 53. The planar shape of the ink receiving portion 53 may be trapezoidal with a rake angle in the paper width direction so as not to be caught. Further, a honeycomb trap for trapping the ink mist sucked in the decompression chamber 67 of the main body 60 may be provided.
[0039]
Further, when the flag of the transfer stage 50 passes through the stage detector that detects the rear side of the transfer stage 50, only the transfer stage 50 is moved to the rear side of the main body 60 and controlled to return to the home position. When the upper end of the paper P passes through the nozzle #N, it may be controlled so that only the transport stage 50 is moved to the rear side of the main body 60 and returned to the home position.
[0040]
Further, the transport stage 50 is moved to the paper discharge position, and a part of the communication port 62 is opened to reduce the suction force of the suction parts 52a and 52b. A flap that can be opened and closed is provided on the upper surface. When the transport stage 50 moves to the paper discharge position, the flap is opened, the inside of the transport stage 50 is made positive pressure, air is blown out from the suction portions 52a and 52b, and the paper P is floated before the paper P may be discharged.
[0041]
Further, in order to discharge the sheet P straight without rotating, the sheet P may be discharged while preventing the rotation by pressing the right side surface of the sheet P against the right edge guide as viewed from the front of the transport stage 50. For this purpose, for example, a separation plate extending in the F direction is provided inside the transfer stage 50 to divide the room into rooms, and the right chamber as viewed from the front of the transfer stage 50 generates negative pressure to suck the paper P and the left side. In this room, positive pressure is generated to cause the paper P to float, and the right side surface of the paper P is pressed against the edge guide to prevent rotation. Also, rubber or the like is attached to the right conveyance surface as viewed from the front of the conveyance stage 50 so that the friction resistance of the right conveyance surface is higher than the friction resistance of the left conveyance surface. To prevent rotation. In addition, the shape of the discharge port 65 is not a simple rectangular shape, but is formed so that the right side is wider than the left side when viewed from the front of the main body 60, and the flow rate of the right air is higher than the flow rate of the left air. In order to prevent the rotation, the right side surface of the paper P is pressed against the edge guide.
[0042]
In each of the above-described embodiments, a printer has been described as an example of an ink jet recording apparatus. However, the present invention is not limited to this, and any recording apparatus having a recording medium conveying apparatus may be used, for example, a facsimile apparatus or a copying apparatus. Even if it exists, it is applicable. Although the present invention has been described with reference to various embodiments, the present invention is not limited to the above embodiments, and may be applied to other embodiments within the scope of the invention described in the claims. Of course.
[0043]
【The invention's effect】
As described above, according to the present invention, a recording medium discharge roller or the like can be dispensed with, so that the recording medium can be discharged in a good state without scars or ink rubbing. Further, when the stage is moved to the recording medium discharge position, the communication port is opened so that the flow path load can be reduced, so that the amount of air exhausted by reducing the suction force that adsorbs the recording medium. The recording medium can be reliably discharged.
[Brief description of the drawings]
FIG. 1 is a side view showing an internal configuration example of an ink jet printer which is one of ink jet recording apparatuses according to an embodiment of the present invention.
2 is a perspective view showing a detailed example of a conveyance stage and a main body of the ink jet printer shown in FIG. 1. FIG.
FIG. 3 is a plan view of FIG. 2;
4 is a flowchart showing an operation example of the ink jet printer shown in FIG. 1;
5 is a first operation diagram and a second operation diagram of the ink jet printer of FIG. 1; FIG.
6 is a third and fourth operation diagram of the ink jet printer of FIG. 1; FIG.
7 is a fifth operation diagram of the ink jet printer of FIG. 1; FIG.
FIG. 8 is a seventh operation diagram of the ink jet printer shown in FIG. 1;
FIG. 9 is a diagram showing nozzles used in the recording head when performing printing without a margin at the upper end with the ink jet printer of FIG. 1;
FIG. 10 is a side view showing an internal configuration of a conventional ink jet printer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Paper feed roller 12 Hopper 13 Paper feed roller 14 Driven roller 18 Carriage 19 Recording head 50 Conveying stage 52a Suction part 52aa Through hole 52b Suction part 52ba Through hole 53 Ink receiving part 53a Through hole 54 Support part 54a Lever 55 Guide shaft 56 Belt Drive mechanism 60 Body 61 Stopper 63 Communication port 64 Communication port 65 Exhaust port 66 Intake fan 67 Decompression chamber 68 Exhaust chamber 69 Ink receiving portion

Claims (4)

An operation for sucking the fed recording medium and an operation for reciprocating in the feeding direction of the recording medium are possible, and a stage for conveying the recording medium by appropriately combining the operations,
A recording medium transport device having suction means for sucking in order to suck the recording medium,
An exhaust port for blowing out an airflow for discharging the recording medium on the stage moved to the medium discharge position is disposed below the stage ,
A communication port for communicating the stage and the suction means is provided,
The recording medium conveying apparatus , wherein the communication port is exposed by the movement of the stage to increase the flow rate of the discharged airflow at the medium discharge position . The air flow for discharging the recording medium, the recording medium conveying apparatus according to claim 1, characterized in that using the exhaust air of the suction means at the time of sucking the recording medium in the stage. Wherein upon discharge of the recording medium, the recording medium conveying apparatus according to claim 2 or 3, characterized in that to generate the airflow greater flow than during recording. In an ink jet recording apparatus that records by ejecting ink onto a transported recording medium ,
An ink jet recording apparatus comprising the recording medium conveying apparatus according to claim 1 .

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