The present invention relates to a liquid ejection apparatus for ejecting liquid toward a target and a method of ejecting liquid using such a liquid ejection apparatus.
An ink jet recording apparatus as an exemplary liquid ejection apparatus is equipped with an ink jet recording head. The ink jet recording head is provided with a large number of nozzles for ejecting ink toward a recording sheet or the like.
Since each nozzle has an aperture, ink is exposed to the air and its solvent such as water evaporates gradually. If that part of the ink which is in the vicinity of the meniscus which is a free surface of the ink in the nozzle is increased in viscosity because of the evaporation of the ink solvent, an ejected ink droplet may fly in an erroneous direction because of a drag by the viscosity-increased ink or a nozzle may clog up.
To prevent various kinds of trouble due to such increase in ink viscosity, what is called flushing operations are performed in which ink is ejected from each nozzle at prescribed intervals (refer to Patent document 1, for example).
For example, as shown in FIG. 1 of Japanese Patent Publication No. 2002-166575A, an ink absorbing member is disposed at a position far from a region where a recording sheet is disposed (referred as a recording region) and a flushing region is established there. A flushing operation is performed in such a manner that the ink jet recording head is moved to the flushing region and ink is ejected there.
However, where the flushing region is provided at a position far from the recording region, the ink jet recording head is moved from the recording region to the flushing region every time a flushing operation is performed.
This means a problem that time is taken for the ink jet recording head to make such a movement to increase a time period required for recording, that is, the use of time is inefficient. The efficiency of use of time in connection with recording is particularly low when recording is performed on a narrow sheet such as a postcard, because a long distance exists between the flushing region and the region where a postcard or the like is disposed.
It is therefore an object of the invention to provide a liquid ejection apparatus which enables an efficient flushing operation, and a method of ejecting liquid using such a liquid ejection apparatus.
In order to achieve the above object, according to the invention, there is provided a liquid ejection apparatus, comprising:
a first region, on which a target medium is placed;
a second region, adjacent to the first region;
a liquid absorbing member, placed in at least the second region; and
a liquid ejection head, being movable above the first region and the second region, and provided with a plurality of liquid ejecting sections from which liquid droplets are ejected, wherein:
each of the liquid ejecting sections is configured so as to eject at least one liquid droplet toward the target medium when it is placed above the first region, and to flush a prescribed amount of liquid toward the liquid absorbing member when it is placed above the second region; and
the liquid ejecting sections are arranged such that at least one of the liquid ejecting sections can be placed above the first region when another one of the liquid ejecting sections is placed above the second region.
Preferably, each of the liquid ejecting sections includes an array of nozzle orifices from which liquid droplets are ejected.
Preferably, a signal for causing each of the liquid ejecting sections to eject at least one liquid droplet with respect to a unit area on the target medium is repetitively applied to the liquid ejection head to flush the prescribed amount of liquid.
Preferably, the liquid ejection head is configured such that liquid droplets are ejected from one of the liquid ejecting sections while the prescribed amount of liquid is flushed from another one of the liquid ejecting sections.
Preferably, the prescribed amount of liquid from at least one of the liquid ejecting sections while the liquid ejection head is moved.
Preferably, a timer counts time, and each of the liquid ejecting sections flushes the prescribed amount of liquid every time when the timer counts a prescribed time period.
Preferably, a timer which counts time, and the prescribed amount of liquid is increased in accordance with an increase of the time counted.
The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:
Embodiments of the present invention will be hereinafter described in detail with reference to the accompanying drawings.
As shown in
The carriage 110 is movable in an X direction indicated by an arrow along a guide shaft 120. Therefore, the recording head 100 that is mounted on the carriage 110 is likewise moved in the arrowed X direction.
The recording apparatus 10 is equipped with a platen 130 on which a target such as a recording sheet P is to be placed. The recording apparatus 10 is also equipped with a sheet feeding roller 140 for moving a recording sheet P in, for example, a Y direction indicated by an arrow.
A recording sheet P to be fed in the arrowed Y direction by the sheet feeding roller 140 is placed on the platen 130. Printing or the like is performed on the recording sheet P in such a manner that the recording head 100 on the carriage 110 ejects ink while the carriage 110 is moved in the arrowed X direction with respect to the thus-placed recording sheet P.
The platen 130 is provided with an absorbing member 131 for absorbing ink that is ejected from the recording head 100. The absorbing member 131 is a porous material such as a sponge. That is, the absorbing member 131 absorbs ink that is ejected so as to reach the outside of a recording sheet P when the recording apparatus 10 performs recording on a peripheral portion of the recording sheet P (what is called marginless recording).
The marginless recording will be hereinafter described with reference to
First, as shown in
Then, marginless recording is performed on a left end portion P2 and a right end portion P3 of the recording sheet P. More specifically, as shown in
Marginless recording on the right end portion P3 in the same manner as on the left end portion P2. Ink that is ejected so as to reach the outside of the right end portion P3 is absorbed by the absorbing member 131 of the platen 130.
Then, marginless recording is performed on a bottom end portion P4 of the recording sheet P. More specifically, the bottom end portion P4 of the recording sheet P is placed on the platen 130 as shown in
The marginless recording on the recording sheet P is performed in the above-described manner. Since ink that is ejected so as to reach the outside of the edges of the recording sheet P is absorbed by the absorbing member 131, and will not be landed and adhered on the platen 130. This prevents staining or the like of a recording sheet P that is supplied by the sheet feeding roller 140 shown in
As shown in
That is, contraction and expansion of a piezoelectric vibrator 103 that are caused by a voltage applied thereto cause the ink in the associated pressure chamber 102 to be ejected from the associated nozzle 104.
As shown in
In each of the nozzles 104 shown in
To prevent such trouble, what is called flushing operations are performed in which the recording head 100 ejects ink from the nozzles 104 at prescribed intervals. In this embodiment, flushing operations are performed such that ink droplets are ejected toward the absorbing member 131 of the platen 130 shown in
As shown in
The controller 13 is connected to not only a timer 15 but also the recording head 100, the carriage 110, the sheet feeding roller 140, etc.
The printer driver 14 incorporates software to be used for sending, to the individual components of the recording apparatus 10, commands for performance of recording, a flash operation, etc. According to the software in the printer driver 14, the controller 13 controls recording and a flushing operation of the recording head 100 and controls operation of the carriage 110, a sheet feeding roller 140, etc.
As shown in
As shown in
The first image data 150 corresponding to a single primary scanning of the recording head 100 is used in the normal recording operation. However, since the nozzles 104 are exposed to the air during the recording to cause drying or the like of the ink in the nozzles 104, a flushing operation needs to be performed every prescribed time.
Therefore, when a lapse of a prescribed time has been detected by the timer 15, flushing data 153 is appended to the right-side marginless recording data 152. The flushing data 153 is for flushing operation to be performed in the flushing region 132 that is adjacent to the left-side marginless recording region 133 shown in
Since flushing data 153 are appended to the first image data 150 to generate the second image data 150a when a flushing operation is to be performed, the recording head 100 can perform a flushing operation immediately after performance of a marginless recording in the left-side marginless recording region 133 shown in
Therefore, it is not necessary to move the recording head 100 to a conventional flushing region that is far from the recording region 134, which solves the problem that this movement requires an extra recording time. The efficiency of use of time in connection with recording can thus be increased.
In the conventional recording apparatus, flushing operations repetitively are executed at a fixed interval during recording operation. That is, every time when a prescribed time period elapses, the recording head is moved to the flushing region which is far from the recording region to flush a prescribed amount of ink. For example, the fixed interval is set to 10 seconds and the prescribed amount of ink (total amount of ink flushed by a single flushing operation) is set to 1170 ng (nanograms).
As described the above, when the timer 15 detects that the prescribed time period elapses, the flushing data 153 is appended to the first image data 150 to generate the second image data 150a. In this embodiment, as a drive signal for causing the recording head 100 to flush the above prescribed amount of ink, the drive signal for causing the recording head 100 to perform recording operation is used.
Specifically, as shown in
Similarly, in the normal mode, a drive signal for causing the recording head 100 to eject 26 ng of ink is repetitively applied for 45 times (45 seg), thereby flushing 1170 ng of total amount of ink. In the draft mode, a drive signal for causing the recording head 100 to eject 39 ng of ink is repetitively applied for 30 times (30 seg), thereby flushing 1170 ng of total amount of ink.
In the conventional configuration, upon the execution of the flushing operation, not only the recording head is moved to the flushing region which is far from the recording region but also it is necessary to supply a drive signal for causing the recording head to perform the flushing operation which is different from a drive signal for causing the recording head to perform the recording operation. However, in this embodiment, not only the flushing region 132 at which the recording head 100 (more specifically, the nozzle array subjected to the flushing operation) is placed to perform the flushing operation is situated adjacent to the recording regions 133, 134 but also the drive signal for the recording operation can be utilized as the drive signal for the flushing operation. Accordingly, the whole of the recording operation can be efficiently and speedily executed.
The ink amount ejected per 1 seg shown in
With the above configuration, even if the recording operation is performed in any one of the operation modes shown in
As shown in
Also in this case, the flushing data 153 can be generated by merely designating the repetitive number of the application of the drive signal for causing the recording head 100 to record a large dot. Specifically, in a case where the flushing operation is executed every 5 seconds, the repetitive number is set to 45 times. Namely, even in a case where the way of executing the flushing operations is changed while the same operation mode is unchanged, it is not necessary to provide a large change with respect to the data format and the driving method for the recording head 100. Accordingly, the whole of the recording operation can be efficiently and speedily executed. The above explanations are applicable to the normal mode and the draft mode.
As shown in
At this time, a recording sheet P and the nozzle arrays 106 to 108 of the recording head 100 are arranged as shown in
Then, as shown in
Then, time information is acquired from the timer 15 and it is judged whether a prescribed time has elapsed (step ST3). That is, it is judged whether an ink ejection failure or the like will possibly occur due to drying or the like of ink in the nozzles 104 that is caused by exposure of the meniscuses of the ink to the air.
If the prescribed time has elapsed, the recording head 100 is subjected to a flushing operation to prevent an ink ejection failure or the like. That is, second image data 150a is generated by appending flushing data 153 to the first image data 150 (step ST4).
Then, recording for a single primary scanning is performed with the second image data 150a (step ST5). More specifically, as shown in
At the same time, since the similar image data 150a are also set with respect to the nozzle arrays 107 and 108 with time differences, the nozzle array 107 performs marginless recording in the left-side marginless recording region 133, and the nozzle array 108 performs recording in the recording region 134. That is, the nozzle arrays 106, 107, and 108 are configured to eject different amounts of ink. The nozzle array 106, which has already completed a recording operation, performs a flushing operation while the nozzle array 107 and the nozzle array 108 are performing recording or the like on a recording sheet P.
In other words, the flushing operation and the recording operations can be performed simultaneously, because the nozzle array 107 is still located in the marginless recording region 133 while the nozzle array 106 is located in the flushing region 132. Since the flushing region 132 is adjacent to the marginless recording region 133, a flushing operation can be performed efficiently. The efficiency of use of time by the entire recording apparatus 10 in connection with recording can be increased by performing a flushing operation efficiently in terms of time in the above-described manner.
As shown in
Then, whether the recording has completed is judged (step ST6). That is, the recording is finished by referring to the data in the printer driver 14.
In this embodiment, the flushing region 132 is located on the right side of the right-side marginless recording region 133. That is, a flushing operation is performed first in a recording operation for a single primary scanning.
More specifically, as shown in
An ink ejection failure or the like due to drying or the like of the nozzles 104 becomes more likely to occur as the time elapses. In view of this, in this embodiment, unlike in the first embodiment, the ink ejection amount is increased as the time elapses. In the first embodiment, a flushing operation is performed using the same ink amount every time the constant time elapses. On the other hand, in this embodiment, the ink amount is changed as the time elapses, whereby flushing operations are performed more effectively.
More specifically, flushing data 253a is generated on the basis of the measured elapsed time T (step ST14). Then, as shown in
Therefore, the recording head 100 can perform, in the flushing region 132 shown in
This embodiment is different from the first embodiment in that no marginless recording is performed. Therefore, unlike in the image data of the first embodiment shown in
In this embodiment, as the nozzle array 106 is moved outward from the recording region 134, ink ejection is halted during the passage of a blank region provided in place of the left-side marginless recording region 133 shown in
Due to the time differences between image data set for the respective nozzle arrays 106 to 108, while the nozzle array 106 is performing the flushing operation in the flushing region 132, the nozzle array 107 stops ejecting ink droplets in accordance with the non-recording data 155 and the nozzle array 108 performs a recording operation with the recording data 151 at the recording region 134.
Since the flushing region 132 is not far from a recording sheet P as in the case of the first embodiment, the recording head 100 can perform a flushing operation quickly.
In addition, the flushing operation can be performed simultaneously with the recording operation. This makes it possible to perform a flushing operation efficiently.
In this embodiment, second image data 450 is generated by appending flushing data 153 at both of leading and trailing ends of the recoding data 151 while inserting non-recording data 155 between recording data 151 and the respective flushing data 153.
This arrangement of data also makes it possible to perform a flushing operation efficiently.
The invention is not limited to the above embodiments that are directed to the ink jet recording apparatus and various changes are possible without departing from the scope of the invention. And the above embodiments can be combined with each other.
Further, the invention is not limited to ink jet recording apparatus but can also be applied to, for example, liquid ejection apparatus using liquid ejection heads that include recording heads used for image recording apparatus such as printers, colorant ejection heads used for manufacture of color filters of liquid crystal displays etc., electrode material ejection heads used for formation of electrodes of organic EL displays, FEDs (field emission displays), etc., and bioorganic material ejection heads used for manufacture of biochips, and sample ejection apparatus as micropipettes.
Number | Date | Country | Kind |
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2004-104322 | Mar 2004 | JP | national |
2005-094754 | Mar 2005 | JP | national |
This is a divisional of application Ser. No. 11/094,515 filed Mar. 31, 2005. The entire disclosure of the prior application, application Ser. No. 11/094,515 is considered part of the disclosure of the accompanying divisional application and is hereby incorporated by reference.
Number | Date | Country | |
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Parent | 11094515 | Mar 2005 | US |
Child | 12818257 | US |