JPH07125226A - Ink jet printer - Google Patents

Abstract

PURPOSE:To increase a printing speed by reducing unnecessary maintenance operation when a decimation mode is selected. CONSTITUTION:A mode control means 47 outputs the initial values of wiping and suction timings stored in a ROM 43 to a timing value memory means 44 at the time of a normal printing mode and outputs the values obtained by doubling the initial values to the timing value memory means 44 at the time of a thinning mode. The timing value memory means 44 stores the wiping and suction timing values outputted from the mode control means 47. When printing operation is started, a wiping instructing means 45 and a suction instructing means 16 read the wiping and suction timing values stored in the timing value memory means 44 and stop the printing operation when printing operation reaches the respective timings to perform wiping or suction operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer having a maintenance means for maintaining an ink jet head.

[0002]

2. Description of the Related Art Conventionally, there is known an ink jet printer provided with a maintenance means for performing maintenance of a head in order to prevent deterioration of print quality. As the maintenance means, specifically, a wiping member slides the nozzle surface of the head to wipe dust and drips, a suction means for sucking ink from the nozzle surface side of the head, or a forced ink from the head. There is a method in which dust and air bubbles in the head are discharged together with a small amount of ink by a forced discharge means that discharges the ink to In particular, in recent inkjet printers, in many cases, the above-mentioned wiping and either suction or forced ejection are used in combination in order to achieve higher printing quality.

In such an ink jet printer, the above maintenance operation is designed to be performed every time a predetermined amount (time, number of characters, number of dots, or number of pages) is printed. As one example thereof, Japanese Patent Laid-Open No. 2-
Japanese Patent No. 141248 and Japanese Unexamined Patent Publication No. 3-5154 disclose an example in which the timing of the wiping operation is changed every predetermined number of dots from the conventional predetermined time.

[0004]

However, in the above-mentioned prior art, since good print quality is always sought, the print speed is delayed to some extent no matter which timing the maintenance is performed. . For example, generally, a printer is used in a test print mode in which a document created by a host computer is printed for the time being,
There are two possible cases, such as a case of making a correct copy based on the result of the test print, and a clear print. However, the user's request these days is that the print quality may be slightly deteriorated in the case of the test print. Anyway, there are many things that I want you to print quickly. Incorporating such a demand, there is conventionally known an ink jet printer capable of selecting a normal print mode in which an image pattern to be printed is printed as it is and a thinning mode in which the pattern is thinned and printed. In the thinning-out mode, the printing quality is reduced, but there are advantages that the consumption amount of ink is reduced and the printing speed is improved.

However, when such an ink jet printer is provided with the above-mentioned maintenance function, the timing of maintenance is the same as that of normal printing even if the user selects the thinning mode for trial printing. Therefore, the printing speed could not be improved so much.

Further, in some conventional ink jet printers, a water repellent layer is provided on the nozzle surface to prevent unnecessary retention of ink, thereby improving the straightness of the ejected ink. In particular, in recent inkjet printers, in many cases, the above-mentioned wiping and water-repellent layer are used together in order to achieve higher printing quality. However, in such an inkjet printer, if the wiping is performed at the same timing as in the case of the trial printing, the water-repellent layer on the nozzle surface is gradually peeled off every time the wiping is repeated.
There has also been a problem of shortening the life of the print head.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an ink jet printer capable of improving the printing speed by reducing unnecessary maintenance operations. .

[0008]

In order to achieve this object, the present invention comprises a maintenance means for performing maintenance of the ink jet head and an actuation means for activating the maintenance means at a predetermined timing, and printing should be performed. In an inkjet printer capable of selecting a normal print mode for printing an image pattern as it is and a thinning mode for thinning and printing the pattern, when the normal print mode is selected, the operation timing of the operating means is set to And a timing changing means for setting the operation timing to a second predetermined value which is larger than the first predetermined value when the thinning mode is selected. There is.

[0009]

In the ink jet printer of the present invention having the above construction, the timing changing means sets the operation timing of the operating means to the first predetermined value when the normal print mode is selected. When the thinning mode is selected, the operation timing is set to a second predetermined value that is larger than the first predetermined value. Then, the operating means operates the maintenance means based on the changed operation timing.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

First, the configuration of this embodiment will be described with reference to FIG. In the housing 21 of the printer 1, the platen 16
2 is rotatably provided in the direction of arrow A in FIG. 2, and the guide shaft 4 is provided along the platen 16 thereof. A carriage 3 is slidably attached to the guide shaft 4, and a belt 7 is attached to the carriage 3. The belt 7 is wound around the idle pulley 8 and the drive pulley 6. The drive pulley 6 is rotated by the drive motor 5, and the rotation of the drive pulley 6 moves the carriage 3 along the guide shaft 4 via the belt 7 in the arrow B direction in FIG. A head 2 is mounted on the carriage 3 so as to face the platen 16, and ink for printing is stored in the head 2.

The printing paper 17 is inserted into the housing 21 in the direction of arrow C in FIG. 2 from the rear of the printer 1, is conveyed in the direction of arrow D along the platen 16, and is discharged from the housing 21 of the printer 1. The printing paper 17 is
When transported to the platen 16, the head 2 ejects ink as the carriage 3 moves, so that required data is printed.

A cap 9 is provided on the left side of the platen 16 in FIG. 2 (near the non-printing position of the head 2), and a cap rubber 10 is attached to the cap 9 so as to be in close contact with the head 2. Further, the cap 9 is attached to the head 2 so as to be movable in the direction of arrow E in FIG. 2, and the cap rubber 10 is appropriately brought into close contact with the head 2. A connecting tube 12 is attached to the cap 9 and is connected to the pump 11. A discharge tube 13 is connected to the pump 11, and the discharge tube 13 is a waste ink tank 1 in which an adsorbent 15 is stored.
Connected to four.

A flexible wiper blade 22 is provided between the platen 16 and the cap 9 at the non-printing position. The wiper blade 22 is attached so as to be movable in the direction of arrow F in FIG. The wiper blade 22 normally stands by at a retracted position where it does not come into contact with the head 2, and during wiping, it is moved to an advanced position where it can be slidably contacted with the head 2 by a motor (not shown).

A water repellent layer (not shown) is provided on the nozzle surface of the head 2. This water-repellent layer is composed of a uniform film of a fluoropolymer in this example, and the nozzle surface is coated with a polymer solution prepared by dissolving the fluoropolymer in a solvent by dipping. It is formed. The material and forming method of the water repellent layer are described in detail in International Publication No. WO92 / 13720, so refer to the description. The water-repellent layer thus formed has an action of forming an ink meniscus at a predetermined position and preventing unnecessary ink from staying on the nozzle surface. That is, when unnecessary ink stays in the vicinity of the nozzle, not only does the ink droplet that attempts to go straight bend the print result and disturbs the printing result, but it also causes clogging, resulting in missing dots. The problem of can be solved.

Next, the circuit configuration of the ink jet printer of this embodiment will be described with reference to the block diagram of FIG. However, the description of the circuit configuration of the mechanism not directly related to the present invention will be omitted.

The CPU 31 for controlling the operation of the ink jet printer of this embodiment has an operation panel 32 which allows the user to select each mode of the printer, a drive motor 5 for driving the carriage 3, and a pump 11 for suctioning. , And a ROM 33 that stores a control program of the printer and also stores an initial value of timing for performing wiping and suction. Note that, as the specifications of the maintenance timing of the present embodiment, the wiping is set to be performed every 30 lines and the suction is performed every page to be printed, and the user sets each timing to 1 / of the initial value. Double,
The setting can be changed to double or triple. Therefore, the ROM 33 stores data of 30 lines and 1 page as initial values of wiping and suction timings, and the operation panel 32 sets the wiping and suction timings to 1/2 times the initial values and 2 times. Double or three
Input means capable of changing settings twice are provided respectively. The CPU 31 is configured to operate as the following means by operating according to the control program.

The timing value storage means 34 is normally RO
If the initial values of the wiping and suction timings stored in M33 and the wiping timings or suction timings are changed by the operation panel 32, the changed values are set until the print end signal is input. Each is configured to store.

When the printing operation is started, the wiping instructing means 35 and the suction instructing means 36 read the values of the wiping and suction timings stored in the timing value storage means 34, and when the printing operation reaches each timing. The printing operation is interrupted, and the wiping or suction operation is performed.

Next, the operation of this embodiment will be described.
First, for example, if the user changes the setting of the wiping and suction timings to twice the initial value by the operation panel 32 in order to change the maintenance timing for reasons such as test printing, the timing value storage means 34 stores the initial value of 2 Doubled 60 rows and a value of 2 pages are stored. Next, when print data is input from a host computer (not shown), the printer starts the print operation based on the data, and the wiping instruction means 35 and the suction instruction means 36 detect the line feed signal transmitted from the host computer. The page break signal is counted and compared with the value stored in the timing value storage means 34.

When the number of printing lines reaches 60, the wiping instructing means 35 suspends the printing operation and
In order to perform wiping, the wiper blade 22 (FIG. 2) is moved by a motor (not shown) to a forward position where it can slidably contact the head 2, and a control signal is sent to the drive motor 5 so that the carriage 3 is not printed from the printing position. Wiping by moving to the position and sliding the nozzle surface. When the number of pages to be printed becomes two, the suction instructing means 36 sends a control signal to the drive motor 5 to move the carriage 3 from the printing position to the non-printing position.
In a state where the cap rubber 10 of the cap 9 shown in (1) is in close contact with the head 2, the pump 11 is operated to suck the head 2.

When a print end signal is sent from the host computer after further printing operation, the timing value storage means 34 re-stores the initial values of the wiping and suction timings stored in the ROM 33 and the operation ends. To do.

With the above-described structure and operation, in the ink jet printer of this embodiment, the head maintenance can be performed at the timing requested by the user. Therefore, when print quality such as test printing is not required, the user can perform maintenance. By setting the maintenance frequency to be low, it is possible to increase the printing speed and prevent the water-repellent film from peeling off. Further, in this embodiment, since the maintenance timing is initialized based on the print end signal, for example, the user changes the maintenance timing for reasons such as trial printing, and based on the timing at the end of printing. Even if you forget to return it, you can automatically print with normal print quality. In addition, in this embodiment,
Since the maintenance timing can be shortened, for example, when the print quality is deteriorated due to peeling of the water-repellent film or the like, it is possible to improve the print quality by frequently performing maintenance.

In the above embodiment, the maintenance timing was changed stepwise on the operation panel, but it is also possible to change the setting continuously, and in addition to the operation panel, the volume, etc. may be changed. May be provided and changed. Further, although the timings of wiping and suction can be changed separately, both timings may be changed at one time.

Further, in the above-described embodiment, wiping is performed in print line units and suction is performed in print page units, but other parameters such as time, the number of dots, and the number of characters may be used. Further, it is also applicable to an ink jet printer of a type in which forced ejection is performed instead of suction. Further, in the above embodiment, the timing of both wiping and suction can be changed, but only one of them may be changed.

Next, a second embodiment will be described with reference to FIG. The description of the same parts as those in the above embodiment will be omitted.

The ink jet printer of this embodiment has two printing modes: a normal printing mode in which an image pattern to be printed is printed as it is and a thinning mode in which the pattern is thinned and printed. Either can be selected according to the type. That is, when the user does not demand the print quality for reasons such as test printing, the thinning mode is selected to reduce the ink consumption and improve the printing speed. The mechanical structure of the ink jet printer of this embodiment is the same as that of the above embodiment shown in FIG.

Next, the circuit configuration of the ink jet printer of this embodiment will be described with reference to the block diagram of FIG. However, the description of the circuit configuration of the mechanism not directly related to the present invention will be omitted.

The CPU 41 for controlling the operation of the ink jet printer of this embodiment includes an operation panel 42 which allows the user to select each printer mode, a drive motor 5 for driving the carriage 3, and a pump 11 for suctioning. A ROM 43 for storing a control program of the printer and an initial value of timing for performing wiping and suction,
A head driver 49 for driving the head 2 is connected to each. In addition, as a specification of the maintenance timing of the present embodiment, the wiping is performed from any nozzle from 2
The initial setting is such that the suction is performed every 40,000 dot printing every time 10,000 dots are printed. Therefore, the ROM 43
Is the initial value of wiping and suction timing,
Data of 20,000 and 40,000 are stored. The operation panel 42 is also provided with an input means for designating a thinning mode. The CPU 41 is configured to operate as the following means by operating according to the control program.

The mode control means 47 normally prints the image pattern to be printed as it is, or when the thinning mode is designated by the operation panel 42, until the print end signal is input. The thinning-out mode is instructed to the thinning-out means 48 described later. Further, the mode control means 47 is obtained by doubling the initial values of the wiping and suction timings stored in the ROM 43 in the normal printing mode and doubling the initial values in the thinning mode. And 80,000 values are output to the timing value storage means 44.

Further, if the instruction from the mode control means 47 is a normal print mode, the thinning means 48 develops the print data from the host computer as it is into an image pattern and outputs it to the head driver 49, and in the thinning mode. For example, the developed image pattern is further thinned out vertically one by one and output to the head driver 49, and at the same time, a control signal is sent to the drive motor 5 in order to double the carriage movement speed.

Further, the timing value storage means 44 is configured to store the values of the wiping and suction timings output from the mode control means 47, respectively.
Further, the wiping instruction means 45 and the suction instruction means 46.
Is a timing value storage means 44 when the printing operation is started.
The values of the wiping and suction timings stored in are read, and when the printing operation reaches each timing, the printing operation is interrupted and the wiping or suction operation is performed.

Next, the operation of this embodiment will be described.
First, for example, when the user selects the thinning mode with the operation panel 42 for reasons such as test printing, the mode control unit 47 instructs the thinning mode to the thinning unit 48, and RO as the wiping and suction timing values.
The value in M43 is doubled and output to the timing value storage means 44. Therefore, the values of 40,000 and 80,000 are stored in the timing value storage means 44. Next, when print data is input from a host computer (not shown), the thinning means 48 develops the print data into an image pattern, further thins out each vertical column and outputs it to the head driver 49, and at the same time, the carriage moving speed. A control signal is sent to the drive motor 5 in order to double the. Therefore, thinning printing with an ink consumption amount of 1/2 and a printing speed of double is performed. Further, the CPU 41 counts the cumulative number of print dots for each nozzle during the printing operation, and outputs the maximum value to the wiping instruction means 45 and the suction instruction means 46. The wiping instruction means 45 and the suction instruction means 46 compare the number of dots output from the CPU 41 with the value stored in the timing value storage means 44.

Here, when the number of dots reaches 40,000, the wiping instructing means 45 performs the wiping operation, and when the number of dots reaches 80,000, the suction instructing means 46 performs the suction operation in the same manner as in the above embodiment.

When the print end signal is sent from the host computer after the printing operation is further performed, the mode control means 47 instructs the thinning means 48 to perform the normal print mode and the wiping and the wiping stored in the ROM 43. The initial value of the suction timing is output to the timing value storage means 44, and the operation ends.

With the above-described configuration and operation, in the ink jet printer of this embodiment, when the user selects the thinning printing in which the printing quality is not required, the maintenance frequency is automatically set to be low, so the printing speed is set. It is possible to accelerate and prevent peeling of the water-repellent film. Further, in this embodiment, since the print mode and the maintenance timing are initialized based on the print end signal, for example, it is possible that the user selects thinning printing and returns the mode at the end of the printing. Even if you forget, you can automatically print in the normal print mode and at the normal maintenance timing.

In the present embodiment, the maintenance timing is performed in dot number units.
Other parameters such as line, page and number of characters may be used. In this case, for example, when performing maintenance on a page-by-page basis, when the thinning mode is selected, the number of dots per page is half the normal number. Should not affect print quality. Then, in the case of carrying out by adding the idea of the above-mentioned embodiment, that is, the idea that the maintenance frequency is halved because of the thinning mode, (1/2) × (1/2)
Therefore, the frequency may be about 1/4, that is, the timing may be about 4 times. This also applies when time, line, and number of characters are used as parameters.

Further, the specification may be such that no maintenance is performed in the thinning mode. Further, it is also applicable to an ink jet printer of a type in which forced ejection is performed instead of suction. Further, in the above embodiment, the timings of both wiping and suction are changed, but only one of them may be changed.

[0039]

As is apparent from the above description, in the ink jet printer of the present invention, unnecessary maintenance operations are reduced when the thinning mode such as test printing, which does not require the printing quality, is selected.
This has the effect of improving the printing speed. Furthermore, when the present invention is applied to an inkjet printer of the type having a water repellent layer on the nozzle surface, peeling of the water repellent layer can be prevented, and the effect of improving the life of the head can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a main part of the inkjet printer.

FIG. 3 is a block diagram showing a circuit configuration of an inkjet printer according to a second embodiment of the present invention.

[Explanation of symbols]

 2 head 5 drive motor 9 cap 10 cap rubber 11 pump 22 wiper blade 31, 41 CPU 32, 42 operation panel 33, 43 ROM 34, 44 timing value storage means 35, 45 wiping instruction means 36, 46 suction instruction means 47 mode control Means 48 Thinning means

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B41J 2/175 B41J 3/04 102 Z

Claims (6)

[Claims] 1. A maintenance means for maintaining an inkjet head, and an actuation means for activating the maintenance means at a predetermined timing, and a normal printing mode for printing an image pattern to be printed as it is, In an inkjet printer capable of selecting a thinning mode for thinning and printing, when the normal printing mode is selected, the operation timing of the operating means is set to a first predetermined value,
The inkjet printer further comprising a timing changing unit that sets the operation timing to a second predetermined value that is larger than the first predetermined value when the thinning mode is selected. 2. The inkjet printer according to claim 1, wherein the maintenance unit is a wiping unit that cleans a nozzle surface of the inkjet head by sliding the nozzle surface. 3. The ink jet printer according to claim 1, wherein the maintenance unit is a suction unit that sucks ink from the nozzle surface side of the ink jet head. 4. The inkjet printer according to claim 1, wherein the maintenance unit is a forced ejection unit that forcibly ejects ink from the inkjet head. 5. A storage unit for storing an initial value of the operation timing, and when the thinning mode is selected, the thinning mode is set to the normal printing mode due to the end of the printing operation in the thinning mode. 2. The inkjet printer according to claim 1, further comprising: a control unit that changes the operation timing to the initial value stored in the storage unit. 6. The ink jet printer according to claim 1, wherein a water repellent layer is provided on the nozzle surface of the ink jet head.