JP2002225311A - Printing up to end of printing paper without staining platen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress buildup of a solidified ink in a groove of a platen when printing is to be carried out up to an end of a printing paper. SOLUTION: The groove set to the platen for receiving ink discharged other than on a printing medium is provided with an ink suction mechanism for sucking the ink. Buildup of the solidified ink to an ink absorber can be suppressed accordingly. A coagulation of the built up ink is prevented from staining a printing head and the printing paper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for forming dots on a recording medium using a print head, and more particularly to a technique for printing up to the end of a printing sheet without soiling a platen.

[0002]

2. Description of the Related Art In recent years, as an output device of a computer,
2. Description of the Related Art Printers that eject ink from nozzles of a print head have become widespread, and printers that can print an image up to the edge of printing paper have been realized. As one of the methods for realizing such printing, there has been proposed a method in which ink discharged outside the edge of the printing paper is absorbed by an ink absorbing material. The ink absorbing material is provided in a groove of a platen that supports the printing paper at the time of printing, and prevents the platen from being stained by ink ejected outside the edge of the printing paper.

[0003]

However, there are cases where the absorbing material cannot sufficiently absorb the ink discharged outside the edge of the printing paper. In this case, the ink may solidify and deposit on the ink absorbing material provided in the groove of the platen. The accumulated ink comes into contact with the print paper passing over the print head and the platen, and causes stain on the print paper.
In particular, a pigment ink using a pigment as a coloring material has a problem that such deposition easily occurs.

The present invention has been made to solve the above-mentioned problems in the prior art, and is a technique for suppressing the accumulation of solidified ink on an ink absorbing material when printing is performed up to the edge of a printing sheet. The purpose is to provide.

[0005]

In order to solve at least a part of the above-mentioned problems, a printing apparatus according to the present invention uses a print head provided with a plurality of nozzles for ejecting ink droplets. A printing apparatus that discharges ink onto a print medium, wherein a head driving unit that drives at least a part of the plurality of nozzles to discharge ink is provided, and the print medium faces the plurality of nozzles. And a platen for supporting the ink, wherein the platen has a groove for receiving ink ejected outside the end of the print medium, and the printing apparatus further comprises: a nozzle for sucking ink from the groove. And an ink suction mechanism.

In the present invention, an ink suction mechanism for sucking ink is provided in a groove provided on the platen for receiving ink ejected other than on the print medium. Deposition can be suppressed. As a result, it is possible to prevent the accumulated solidified ink from staining the print head and the printing paper.

In the above-mentioned printing control apparatus, a main scanning drive section for performing main scanning by driving at least one of the print head and the printing medium, and intersects the printing medium with the main scanning direction between the main scanning. And a sub-scanning drive unit that performs sub-scanning by driving in the direction, wherein the groove has a pair of side grooves provided at both ends of the print medium in the main scanning direction. good.

[0008] In this case, it is possible to suppress the accumulation of the ink that has fallen from the both sides of the print medium and has fallen into the groove.

In the above printing control apparatus, the platen may further include an upstream groove provided at a position facing at least an upstream end of the plurality of nozzles in the sub-scanning direction; And a downstream groove provided at a position facing at least a nozzle located at a downstream end in the sub-scanning direction of the nozzles, wherein the ink suction mechanism includes the upstream groove and the downstream groove. It is preferable that the ink can be sucked from the ink.

In this case, it is possible to suppress the accumulation of ink falling off the leading edge or the trailing edge of the printing paper and falling into the groove.

In the above-mentioned printing control device, the upstream groove, the downstream groove, and the side groove are divided so that the ink suction mechanism can suction each ink separately. Preferably, at least one of the upstream groove, the downstream groove, and the side groove is selected so as to be able to suck ink.

In this case, for example, there is an advantage that the suction force can be increased by narrowing the suction area at a time.

In the above printing control apparatus, it is further determined in real time which of the upstream groove, the downstream groove and the side groove is to be ejected with ink, and It is preferable to provide an ink suction controller for controlling the ink suction mechanism in order to suck ink from the groove formed.

This has the advantage that the ink can be sucked only when there is a possibility that the ink lands in each groove.

The present invention is embodied in a carrier including a printing apparatus, a computer program for causing a computer to realize the method or the function of the apparatus, a recording medium storing the computer program, and the computer program. It can be realized in various forms such as a data signal.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in the following order based on embodiments. A. Overview of Embodiment: Configuration of printing device: Sequence of ink suction: D. Modification:

A. Outline of Embodiment: FIG. 1 is a schematic diagram of an ink suction mechanism provided in a groove of a platen. Above the print medium P, a print head (not shown) for discharging ink onto the print medium P is arranged. On the lower side of the print medium P, a platen 2 supporting the print medium P is located at a position where a plurality of nozzles of the print head face each other.
6 are arranged. The printing medium is also called a printing paper.

The platen 26 is provided with a groove 126 for receiving ink droplets discharged around the printing medium P. An ink absorbing material 127 for absorbing ink that has landed in the groove 126 is embedded in the groove 126. A space is provided between the lower surface (not shown) of the ink absorbing material 127 and the bottom of the groove 126. This space is a sealed space by bonding between the periphery of the ink absorbing material 127 and the groove 126. At the bottom of the groove 126, a hole (not shown) penetrating toward the back side of the platen 26 (the side opposite to the print medium P) is provided. In this hole, the hose 220 of the ink suction mechanism 200
Are combined.

The ink suction mechanism 200 includes a hose 220
And a pump roller 230. The pump roller 230 has two small rollers 232 and 232 near its periphery.
234. These two small rollers 232,
Hose 220 is wound around 234. When driven by a paper feed motor (described later) and the pump roller 230 rotates in the direction of arrow A, the small rollers 232,
The air in the hose 220 is pushed by the 234. As a result, the air in the closed space formed by the lower surface of the ink absorbing material 127 and the bottom of the groove 126 is exhausted. As a result, the ink discharged above the ink absorbing material 127 is sucked. This ink is discharged to a waste ink discharge unit (not shown) via the hose 220.

In the embodiment of the present invention, the ink absorbing material 127 is used.
Since the ink ejected above is suctioned using the ink suction mechanism, the accumulation of solidified ink on the ink absorbing material 127 provided in the groove 126 of the platen 26 can be suppressed. As a result, it is possible to prevent the ink accumulated on the ink absorbing material 127 from coming into contact with the print medium P and becoming dirty. Further, it is possible to prevent the deposited ink from adhering to the print head 28 and soiling the print medium P.

In the claims, "outside the end of the print medium" means near the end of the print medium,
In addition, it means outside the area of the print medium. In addition, when the print medium has a hole, it includes not only the outside of the outer periphery of the print medium but also the inside of the circumference of the hole.

B. Configuration of Printing Apparatus: FIG. 2 is a schematic configuration diagram of the color printer 20. The color printer 20
A sub-scanning drive unit that conveys the printing paper P in the sub-scanning direction by the paper feed motor 22, a main scanning drive unit that reciprocates the carriage 30 in the axial direction (main scanning direction) of the paper feed roller 25 by the carriage motor 24, A head drive mechanism that drives a print head unit 60 (also referred to as a “print head assembly”) mounted on the carriage 30 to control ink ejection and dot formation, and a paper feed motor 22, a carriage motor 24, Head unit 60
And a control circuit 40 for exchanging signals with the operation panel 32. The control circuit 40 includes a connector 56
Is connected to the computer 90 via the. Note that the control circuit 40 also has a function as a head driving unit in the claims.

The sub-scanning drive unit for transporting the printing paper P includes a gear train (not shown) for transmitting the rotation of the paper feed motor 22 to the paper feed roller 25 and the pump roller 230. The gear train that transmits the rotation of the paper feed motor 22 to the pump roller 230 includes a clutch that turns on and off the transmission. Further, a main scanning drive unit for reciprocating the carriage 30 includes a sliding shaft 34 erected in parallel with the axis of the paper feed roller 25 and slidably holding the carriage 30.
A pulley 38 for extending an endless drive belt 36 between the carriage motor 24 and a position sensor 39 for detecting the origin position of the carriage 30 are provided.

FIG. 3 is an explanatory diagram showing the arrangement of the ink jet nozzles Nz in the print head 28. These nozzles are arranged such that ink is ejected for each color of black (K), cyan (C), light cyan (LC), magenta (M), light magenta (LM), and yellow (Y).
The nozzles are composed of a set of nozzle arrays, each of which has 48 nozzles arranged in a line at a constant nozzle pitch k.
The “nozzle pitch” is a value indicating how many rasters (that is, how many pixels) the intervals in the sub-scanning direction of the nozzles arranged on the print head are. For example, the pitch k of the nozzles arranged at intervals of three rasters is 4
It is.

FIG. 4 is an exploded perspective view of the platen 26 in the embodiment of the present invention. Platen 2 shown in FIG.
As shown in FIGS. 4B to 4D, 6 mainly includes a platen frame 125 having a groove 126, an ink absorbing material 127, and an ink absorbing material supporting portion 128. The ink absorbing material 127 is formed of a porous sponge material for absorbing ink. Note that the ink absorbent support portion 128 is shown upside down for easy understanding.

The platen frame 125 has a groove 1 for receiving ink droplets not ejected onto the print medium P.
26. At the bottom of the groove 126, at least one hole (not shown) penetrating the back side of the platen frame 125 is provided. Ink absorber support 12
8 is fitted into the groove 126 with the upside down from the state shown in FIG. The ink absorbing material 127 is fitted on the upper part of the fitted ink absorbing material supporting portion 128. Further, the periphery of the ink absorbing member 127 is adhered to the platen frame 125 in order to secure the confidentiality under the ink absorbing member 127. In this way, a closed portion is formed below the ink absorbing material 127. This sealing part is divided into four parts together with the groove part. The details will be described later.

FIG. 5 is a sectional view of the platen 26 showing the principle of suction of ink. Since the ink absorbing material 127 is supported by the ink absorbing material supporting portion 128, a closed area is formed below the ink absorbing material 127. This sealed area has a low pressure because the air inside is sucked out by the ink suction mechanism 200. As a result, the pressure inside the ink absorbing material 127, which is a porous sponge material, is also low.

Ink Drop I Discharged from Print Head 28
p adheres to the upper part of the ink absorbing material 127 which is a porous sponge material. Since the pressure inside the ink absorbing material 127 is low, the attached ink droplet Ip is sucked into the ink absorbing material 127 and falls to the bottom 126b of the groove 126. Then, the ink is sucked by the hose 220 of the ink suction mechanism 200 and discharged to a waste ink discharge unit (not shown). As described above, the platen 26 has a structure capable of discharging the ink discharged outside the printing paper.

C. Ink Suction Sequence: FIG. 6 is an explanatory diagram showing the details of the division of the platen 26 and the ink suction mechanism 200 in the embodiment of the present invention. As aforementioned,
The groove 126 includes an upstream groove 126 f and the downstream groove 12.
6r and two side grooves 126s.
Each of the divided grooves has an ink suction mechanism 2
00 hose 220 is connected. Each of the hoses 220 has a valve V1 controlled by the control circuit 40.
To V3, the ink suction mechanism 200
Can suction ink by selecting at least one of the divided grooves.

FIG. 7 is a flowchart showing a sequence of ink suction. In step S101, the user sets a borderless print mode on a print mode setting screen (not shown) on the monitor of the computer 90 (FIG. 2). The borderless print mode is a print mode in which printing is performed up to the edge of the print medium P. In this print mode,
The ink droplet that has left the end of the print medium P is ejected to the groove 126 of the platen 26. When the user sets borderless printing, the clutch that transmits the rotation of the paper feed motor 22 to the pump roller 230 is turned on. This allows
The drive shaft of the paper feed motor 22 (FIG. 2) is the ink suction mechanism 2
00 is connected. At this time, since the valve V0 (FIG. 6) is opened, the hose 220 is open to the atmosphere.

As described above, in this embodiment, when borderless printing is set in the setting of the print mode, the ink suction mechanism 200 becomes operable. However, the operation setting method is not limited to such a method. For example, the ink suction mechanism 200 may be set to always operate, or may be set to operate only when a pigment ink with a large amount of ink accumulation is used. Although the paper feed motor 22 is used to drive the ink suction mechanism 200 in this example, a dedicated motor for the ink suction mechanism 200 may be provided.

In step S102, the paper feed motor 22
Starts driving, and the sub-scan feed of the print medium P starts.
At this time, the pump roller 230 connected to the paper feed motor 22 also rotates, and the ink suction mechanism 200 operates.
At this time, air is sucked through the valve V0. As described above, when the ink is not ejected into the groove 126, the load on the paper feed motor 22 is reduced by opening the hose 220 connected to the ink suction mechanism 200 to the atmosphere. When a certain period of time has elapsed after the start of paper feeding of the printing medium P, the leading end of the printing medium P is
6r is reached (step S103).

FIG. 8 is an explanatory view showing the state of feeding of the printing paper P. In FIG. 8A, the printing paper P is held and fed by the upstream paper feed rollers 25a and 25b (sub-scan feed), and the leading end Pf of the print paper P is set to the upstream groove 12.
6f, and reaches the opening of the downstream groove 126r. At this time, the ink droplet Ip has already been ejected from the print head 28 to print the leading end Pf of the printing paper P. As described above, since the ejection of the ink is started when the leading end Pf of the printing paper P is on the upstream side of the nozzle # 1, a margin is formed at the front end Pf of the printing paper P even if there is some paper feeding error. An image can be printed to the edge without the need. The ink droplets that did not land on the printing paper P
The ink landing material 127r on the downstream side lands.

In step S104, the downstream groove 126
The suction of the ink is started from r. This is the control circuit 4
0 closes valve V0 (FIG. 6) and closes valve V1.
It is done by opening. The timing of opening and closing these valves may be determined, for example, according to the sub-scan feed amount of the print medium P, or according to the area of the print image (for example, the timing of printing the leading edge Pf of the print paper P). You may decide. At this time, a sequence may be adopted in which the valve V2 (FIG. 6) is simultaneously opened. In this case, the ink discharged to the side groove 126s can also be sucked. However, the suction force of the downstream groove 126r is reduced. As described above, the control circuit 40 also functions as an “ink suction control unit” in the claims.

When the paper is further fed, the leading end Pf of the print medium P passes over the opening of the downstream groove 126r (S105). The front end Pf of the print medium P is
After passing over the opening of 6r, the ejection of ink droplets to the downstream groove 126r is stopped. This is because all the ink discharged onto the opening of the downstream-side groove 126r lands on the printing paper P.

In step S106, the downstream groove 126
The suction from r is stopped, and the suction from side groove 126s is started. This is performed by the control circuit 40 opening the valve V2 and closing the valve V1. At this time, as shown in FIG. 8B, ink droplets that have come off from both sides of the print medium P are received by the side grooves 126s.

When the paper is further fed, the rear end Pr of the print medium P reaches the opening of the upstream groove 126f (S107). The rear end Pr of the print medium P is the upstream groove 12.
When the ink reaches the opening 6f, ejection of ink droplets to the upstream groove 126f starts.

In step S106, the side groove 126s
Is stopped, and suction from the upstream groove 126f is started. This is performed by the control circuit 40 opening the valve V3 and closing the valve V2. At this time, as shown in FIG.
The ink droplet which has come off from the rear end Pr is received by the upstream groove 126f and is sucked.

When the paper is further fed, the rear end Pr of the printing paper P passes over the opening of the upstream groove 126f (S109). The rear end of the printing paper P is the upstream groove 126.
After passing over the opening of f, the ejection of the ink droplet to the upstream groove 126f is stopped. This is because, since the printing on the rear end Pr of the printing paper P has been completed, the ejection of the ink by the nozzles on the opening of the upstream groove 126f is stopped.

In step S110, the upstream groove 126
The suction from f is stopped, and the suction of the ink ends. This is performed by the control circuit 40 opening the valve V0 to open the atmosphere and closing the valve V3. Thereafter, when the sub-scan feed of the print medium P is stopped, the pump of the ink suction mechanism 200 is also stopped. After the suction from the upstream groove 126f is stopped, the side groove 126s
May be performed.

As described above, in this embodiment, since the ink droplets can be sucked only from the one into which the ink droplets are ejected, the ink can be efficiently sucked. However, the sequence of ink suction is not limited to this method. For example, the ink suction operation may be performed for each page or for each job. Further, the groove 126 need not necessarily be divided.

D. Modifications: The present invention is not limited to the above-described examples and embodiments, and can be carried out in various modes without departing from the gist thereof. For example, the following modifications are also possible. is there.

In the above embodiment, the groove provided on the platen has a rectangular shape, but the shape of the groove is not limited to a rectangle. The groove has only to have a shape capable of receiving ink ejected from the end of the printing paper, and may be, for example, a single linear groove extending in the main scanning direction.

Further, the suction of the ink does not necessarily have to be performed from the entire groove portion. For example, the suction may be performed only from the groove portion where the ink discharge amount is large.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an ink suction mechanism provided in a groove of a platen.

FIG. 2 is an explanatory diagram illustrating a configuration of a printer.

FIG. 3 is an explanatory diagram showing an arrangement of inkjet nozzles Nz in a print head 28.

FIG. 4 is an exploded perspective view showing an outline of a platen 26 in the embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating an outline of a platen 26 illustrating a principle of suction of ink.

FIG. 6 is an explanatory diagram showing the details of the division of the platen 26 and the ink suction mechanism in the embodiment of the present invention.

FIG. 7 is a flowchart showing a sequence of ink suction.

FIG. 8 is an explanatory diagram showing a state of paper feeding of the print medium P.

[Explanation of symbols]

 Reference Signs List 20 color printer 22 paper feed motor 24 carriage motor 25 paper feed roller 25a, 25b upstream paper feed roller 26 platen 28 print head 30 carriage 32 operation panel 34 sliding shaft 36 drive belt Reference Signs List 38 pulley 39 position sensor 40 control circuit 56 connector 60 print head unit 90 computer 125 platen frame 126f upstream groove 126r downstream groove 126s side groove 127 ink absorbing material 128 ink absorption Material support portion 200: ink suction mechanism 220: hose 230: pump roller 232, 234: small roller

Claims (8)

[Claims] 1. A printing apparatus for ejecting ink onto a print medium using a print head provided with a plurality of nozzles for ejecting ink droplets, wherein at least a part of the plurality of nozzles is driven. A head drive unit for discharging ink; and a platen for supporting the print medium so as to face the plurality of nozzles, wherein the platen receives the ink discharged to the outside of the end of the print medium. The printing apparatus further comprising: an ink suction mechanism for sucking ink from the groove. 2. The printing apparatus according to claim 1, further comprising: a main scanning drive unit that performs main scanning by driving at least one of the print head and the printing medium; A sub-scanning drive unit that performs sub-scanning by driving the medium in a direction that intersects the main scanning direction, and the groove portion includes a pair of A printing device having a side groove. 3. The printing apparatus according to claim 2, wherein the platen is further provided at a position facing a nozzle located at least at an upstream end in the sub-scanning direction among the plurality of nozzles. An upstream groove, and a downstream groove provided at a position facing at least a nozzle located at a downstream end in the sub-scanning direction among the plurality of nozzles; A printing device capable of sucking ink from a side groove and the downstream groove. 4. The printing apparatus according to claim 3, wherein the upstream groove, the downstream groove, and the side groove are separated so that the ink suction mechanism can suction each ink separately. The printing apparatus, wherein the ink suction mechanism can select at least one of the upstream groove, the downstream groove, and the side groove to suction ink. 5. The printing apparatus according to claim 4, further comprising: determining in real time which of the upstream groove, the downstream groove, and the side groove the ink is ejected. A printing apparatus comprising: an ink suction control unit that controls the ink suction mechanism so as to suction ink from the determined groove portion. 6. A printing method for ejecting ink onto a print medium using a print head provided with a plurality of nozzles for ejecting ink droplets, wherein the ink is ejected outside a groove of the print medium. Preparing a platen having a groove for supporting the print medium, driving at least a part of the plurality of nozzles to eject ink, and sucking ink from the groove. And a printing method. 7. A computer program for controlling a printing apparatus that discharges ink onto a print medium by using a print head provided with a plurality of nozzles that discharge ink droplets, wherein the printing apparatus includes the plurality of nozzles. A head driving unit that drives at least a part of the nozzles to discharge ink, and supports the print medium so as to face the plurality of nozzles, and discharges the print medium to the outside of the end of the print medium. A platen having a plurality of divided grooves for receiving the divided ink, and an ink suction mechanism capable of sucking ink from each of the plurality of divided grooves, wherein the computer program comprises: A function of determining in real time which of the divided grooves the ink is ejected, and the determined groove The ink suction mechanism and controlling functions, a computer program for realizing the printing device for aspirating ink from. 8. A computer-readable recording medium on which the computer program according to claim 7 is recorded.