JP2002103694A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer in which the service life of printing parts in a print head can be equalized and cleaning operation can be carried out optimally. SOLUTION: The printer having a plurality of printing parts arranged in parallel and operated in parallel comprises means for counting the number of times of using each printing part, and a control means for comparing the number of times of using respective printing parts and distributing print data preferentially to printing parts having a smaller number of using times.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus for arranging / operating a plurality of printing units in parallel, and more particularly to equalizing the life of a printing unit such as a print head and performing an optimum cleaning operation. To a printing device that can be used.

[0002]

2. Description of the Related Art In the case of producing a large amount of printed materials, a printing apparatus that realizes high-speed printing by arranging a plurality of printing units in parallel and distributing print jobs and operating these printing units in parallel. For example, Japanese Patent Application Laid-Open No. 11-3
No. 48385, etc. According to this,
By operating a plurality of printing units in parallel, printing can be performed at a higher speed as compared with a printing apparatus using only one printing unit having the same performance.

[0003]

In such a printing apparatus, since a plurality of printing sections are arranged, the printing section is likely to vary in usage depending on the printing sections. For example, when printing a small number of prints, or when printing a printed material in which print data to be sorted out is smaller than the arranged print sections, the print section that is always used and, conversely, the print section that is hardly used But it tends to stand out. Such a situation is likely to occur even in a printed matter in which the data amount is uneven for each page.

In such a case, for example, when attention is paid to the life of the print head, there is a problem that the more frequently used specific print head is worn out, the shorter the life becomes.

In the case of an ink jet type print head, clogging or the like is likely to occur due to drying of nozzles if the print head is not used for a long time. There is also a problem that troubles such as serious clogging are likely to occur.

In order to prevent such clogging, there is a method of periodically performing a cleaning process of the print head. However, too frequent cleaning leads to waste of ink and a printing process that does not require cleaning. Unnecessarily cleaning is performed on the head. Furthermore, if cleaning is performed on all print heads at the same time, printing cannot be performed until the cleaning is completed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described situation, and is intended to prevent the frequency of use of a printing unit from being biased toward a specific printing unit and to level the life of each printing unit. It is an object of the present invention to provide a printing device that can perform the printing.

It is a second object of the present invention to provide a printing apparatus capable of eliminating variations in the length of unused time of a printing section and preventing the printing section from being left unused for a long time. With the goal.

A third object of the present invention is to provide a printing apparatus capable of cleaning a printing section at a required timing to prevent waste of ink and the like.

[0010]

In order to solve the above problems, a first feature of a printing apparatus according to the present invention is a printing apparatus in which a plurality of printing units are arranged in parallel and operated in parallel. A use frequency measuring unit that measures the number of uses for each printing unit, a control unit that compares the number of times of use of each of the printing units, and preferentially distributes print data to a printing unit with a small number of times of use of each of the printing units; It is characterized by having.

A second feature of the printing apparatus according to the present invention is that in a printing apparatus in which a plurality of printing sections are arranged in parallel and operated in parallel, an unused time for measuring an unused time for each of the printing sections is provided. It is characterized by having a time measuring means and a control means for comparing the unused time of each printing section and preferentially distributing print data to a printing section having a long unused time among the printing sections.

More preferably, when the difference between the number of times of use of the printing section having the largest number of uses and the number of times of use of the printing section having the least number of uses is less than a predetermined threshold value, the control means preferably comprises: The print data is preferentially allocated to the printing section having a long unused time, and if the difference in the number of uses is equal to or more than a predetermined threshold value, the print data is preferentially given to the printing section having a small number of uses among the printing sections. It is characterized by sorting.

A third feature of the printing apparatus according to the present invention is that in a printing apparatus in which a plurality of printing sections are arranged in parallel and operated in parallel, an unused time for measuring an unused time for each of the printing sections is provided. It is characterized by having a time measuring means and a control unit for performing a cleaning process of the printing unit for the printing unit whose unused time exceeds a predetermined time.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 4 is a configuration diagram mainly showing a configuration example of a mechanical portion of a printing apparatus according to the present invention. FIG. 3 is a diagram showing a control system of the printing apparatus shown in FIG. It is a block diagram which shows the example of a structure typically.

This printing apparatus forms an image on a print sheet P based on print data transmitted from an external device (for example, a personal computer or the like), and stacks printed sheets 18 on a discharge tray 17 in a predetermined order. This is a printing apparatus having a collator function for discharging paper.

In this printing apparatus, as shown in FIG. 4, printing units (201 to 206) including printing units (221 to 226) for forming images on printing paper P can operate in parallel. As shown in FIG.
(Stage) are arranged in parallel. In this way, by arranging a plurality of printing units (201 to 206) related to printing in parallel, for example, when a large amount of printed matter is created, a print job is distributed to each printing unit (201 to 206). Can be operated in parallel,
High-speed printing can be realized.

Below the lowermost printing unit 226, a sheet tray 15 on which the printing sheets P are stacked, or the printing sheets P are taken out one by one from the sheet tray 15 and fed to the sheet feeding path 21 at a predetermined timing. A paper feed unit including paper means 16 and the like, a paper discharge unit that receives printed printed materials 18 from a paper discharge conveyance path 29 and stacks them on a paper discharge tray 17, and a control unit 11 that controls the entire printing apparatus are provided. I have.

The control unit 11 includes an optimum head selecting unit 1
And a storage device 14 for storing data such as print data, various control programs, and the like.
21 to 226).

When the printing process is started, the printing paper P is sucked by the paper feeding / conveying section 21 by air and conveyed by a belt.
Each of the printing units (221 to 226) is provided with a paper feed switching unit, and is provided with a target printing unit (221 to 226).
26), the printing paper P is distributed to the printing units (221 to 226) of each stage by switching the corresponding paper feed switching unit in the direction of the printing unit. Done. Printed matter 18
Is subjected to a predetermined collation process or the like, and is discharged to the discharge tray 17 through the discharge conveyance path 29.

Each of the printing units (221 to 226) includes communication means (271 to 271) for communicating with the print heads (231 to 236), the control unit 11, and other printing units.
276), unused time measuring means (251 to 256), print head counting means (261 to 266), and memories (241 to 241) for storing measured data, measurement programs, and the like.
246).

Print head counting means (261 to 26)
6) measures the number of times the print head of each printing unit is used, and can be performed by software using a measurement program, or can be performed by hardware using a counting circuit or the like. When the print head is replaced with a new head, the number of times of use which has been measured so far is reset, and measurement is started again.

The number of times the print heads (231 to 236) are used is measured, for example, by using each print head (231 to 23).
6) a method of measuring the ejection amount of the ink ejected from
A method of measuring the number of movements of the carriage in the main scanning direction,
It can be realized by a method of measuring the number of prints for each printing unit (221 to 226) or the like. When the power of the printing apparatus is turned off, the measured values are stored in a nonvolatile memory (241 to 246) or a storage device having a built-in power supply.

Unused time measuring means (251 to 256)
Is to measure the elapsed time since the print head of each printing unit was not used, and it can be done by software using a measurement program,
It can also be performed by hardware using a counting circuit or the like. When printing is performed by the print head or when the cleaning operation of the print head is performed, the elapsed time measured so far is reset, and measurement is started again. It is preferable that the elapsed time measurement process be performed by a storage device having a built-in power supply so that the elapsed time measurement can be continued even when the power of the printing apparatus main body is turned off.

In the present invention, each printing unit (20
1 to 206) of the print heads (231 to 23).
By controlling the use status of 6) and controlling the print unit to which the print head with low use frequency belongs to preferentially printing, the variation in use frequency is suppressed, and the life of the specific print head is shortened. To prevent Thereby, not only is the variation in the degree of wear of the print heads (231 to 236) suppressed, but also the variation in the degree of wear of the motors and belts for driving the print heads (231 to 236) is suppressed. Can be.

As described above, each print head (23
By suppressing the variation in the use frequency of the print heads (1 to 236), there should be no print head whose use frequency is extremely low, but not all print heads are used every time. Accordingly, printing is performed by managing the unused time of the print heads (231 to 236) and controlling the print unit to which the print head having a long unused state belongs to perform printing preferentially. There is no longer any print head that is left unattended for a long period of time, and obstructions such as clogging can be prevented without frequent head cleaning processing.

The processing control for managing the use state of the print head and the processing control for managing the unused time of the print head can achieve their intended purposes even if they are independently controlled. However, it is more effective to use them in combination.

FIG. 1 shows a case where the optimum head selecting means 12 in the control unit 11 performs a process control for managing the use status of the print head in combination with a process control for managing the unused time of the print head. 9 is a flowchart illustrating an example of a processing procedure to be performed.

When printing, each printing unit (201 to 201)
In order to distribute the print job (print page) to the print head (206), first, the variation in the frequency of use of the print heads (231 to 236) for each print unit (201 to 206) is examined. Specifically, the print head counting means (261 to 261)
266) measured by each printing unit (201 to 206)
From the number of times the print heads (231 to 236) were used, the number of times the print head was used the most (ma)
x) and the number of uses (m
in), and compares the difference between the number of times of use of the print head with the largest number of uses (max) and the number of times of use of the print head with the least number of uses (min) with a predetermined threshold value (X) (Step 01). ).

If the difference between the number of times of use (max) of the print head with the highest number of uses and the number of times of use (min) of the print head with the lowest number of uses is smaller than a predetermined threshold (X), It is determined that the variation in the frequency of use of the print heads (231 to 236) for each unit (201 to 206) is small, and the print head having the largest unused time (T) measured by the unused time measuring means (251 to 256). Is selected (Step 02).

Conversely, when the difference between the number of times of use (max) of the most frequently used print head and the number of times of use (min) of the least frequently used print head is equal to or greater than a predetermined threshold value (X). It is determined that the variation in the frequency of use of the print heads (231 to 236) for each print unit (201 to 206) is large, and the print unit to which the print head with the least number of uses (min) belongs is selected (Step 06).

Next, the print pages are sorted to the selected printing unit, the printing process is performed (Step 03), and the unused time (T) of the used print head is reset (Step 04).

If there is a subsequent print page, Step 01
Then, if there is not, the process ends (Step 05).

As described above, each printing unit (2
01 to 206), the variation in the frequency of use of the print heads (231 to 236) is checked. If the variation is small, a print head with a long unused time is selected, and the print head is left unused for a long time. It is controlled to eliminate the print head. Conversely, when the variation is large, the print head that is used less frequently is selected and controlled so as to suppress the variation, so that very effective processing control can be performed.

In Step 02 to Step 03, when allocating print pages to the selected print head, depending on the document data amount, pages having a large data amount are preferentially allocated to the print heads that are used less (min). In addition, the amount of data can be weighted. Also, the number of pages can be weighted, such as three pages for one print head, two pages for another print head, and one page for the remaining print heads.

(Second Embodiment) Unused time measuring means (2
By managing the unused time of the print heads (231 to 236) by the print heads (231 to 236),
When the unused time of (236) reaches a predetermined time, it is possible to control to perform the cleaning operation individually for each print head (231 to 236), so that the cleaning operation can be performed at an optimal timing. It is possible to prevent waste of ink due to useless cleaning operation.

FIG. 2 is a flowchart showing an example of a processing procedure to be performed by the control unit 11 when the power of the printing apparatus is turned on, for example.

First, a printing unit having a unit number (N = 1) is selected (Step 11).

The unused time (T) of the selected printing unit (N) is determined (Step 12) and compared with a predetermined threshold value (Y) (Step 13).

When the unused time (T) of the selected printing unit (N) is larger than the predetermined threshold value (Y), the printing unit of the printing unit (N) is subjected to nozzle suction or wiping. The cleaning operation is performed (Step 15), and the unused time (T) of the printing unit is reset (Step 1).
6).

If the unit number (N) has reached the number of printing units, the process is terminated.
4), add 1 to the unit number (N) and return to Step 12 (Step 17).

Note that the above-described processing is not limited to the time when the power of the printing apparatus is turned on, but may be performed, for example, using the time during which printing is on standby.

Further, it goes without saying that the control of the cleaning operation described in the second embodiment can be performed in combination with the print job distribution control described in the first embodiment.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the embodiments, and various improvements and modifications may be made without departing from the gist of the present invention. .

Accordingly, the present invention must be limited only by the matters specifying the invention according to the claims that are reasonable from this disclosure.

[0046]

According to the present invention, the use status of each print head of each print unit is managed, and the print unit to which the print head with a low frequency of use belongs is controlled so as to perform printing preferentially. Reduce the variation in frequency,
Prevent the life of a particular printhead from being shortened. As a result, not only variations in the degree of wear of the print heads are suppressed, but also variations in the degrees of wear of the motors and belts for driving the respective print heads can be suppressed.

Further, the unused time of the print head is managed,
By controlling the printing unit to which the print head that has been unused for a long period of time preferentially to perform printing, there is no print head that is left unused for a long time without printing, and the head cleaning process is performed frequently. Even without performing, the obstacle such as clogging can be prevented.

By managing the unused time of the print head by the unused time measuring means, when the unused time of each print head reaches a predetermined time, the cleaning operation is performed individually for each print head. In addition, the cleaning operation can be performed at an optimum timing, and the waste of the ink due to the useless cleaning operation can be prevented.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an example of a processing procedure of a control unit according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating an example of a processing procedure of a control unit according to a second embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration example of a printing apparatus according to the first and second embodiments of the present invention.

FIG. 4 is a configuration diagram illustrating a configuration example of a printing apparatus according to the first and second embodiments of the present invention.

[Explanation of symbols]

 11. Control unit 12. Optimal head selection means 13. Communication means 14. Storage device 15. Paper feed tray 16. Paper supply means 17. . Output tray 18. Printed material 21. Feeding transport path 29. Output discharging path 201 to 206. Printing units 221 to 226. Printing section 231 to 236. ... Print heads 241-246 ... Memory 251-256 ... Unused time measuring means 261-266 ... Print head counting means 271-276 ... Communication means P ... Printing paper

Claims (5)

[Claims] 1. A printing apparatus in which a plurality of printing units are arranged in parallel and operated in parallel, wherein a usage count measuring unit for measuring the usage count of each printing unit is compared with the usage count of each printing unit. And a control unit for preferentially distributing print data to a printing unit that is used less frequently among the printing units. 2. The printing apparatus further includes an unused time measuring unit for measuring an unused time for each of the printing units, and the control unit includes a printing unit having the largest number of times of use and a printing unit having the least number of times of use. If the difference in the number of uses with a small number of printing units is less than a predetermined threshold, print data is preferentially distributed to the printing unit with a long unused time among the printing units, and the difference in the number of uses is predetermined. 2. The printing apparatus according to claim 1, wherein, when the threshold value is equal to or greater than the threshold value, the print data is preferentially sorted to a print unit having a smaller number of uses among the print units. 3. The printing apparatus according to claim 2, wherein the control unit performs a cleaning process on the printing unit for an unused time exceeding a predetermined time. 4. A printing apparatus in which a plurality of printing units are arranged in parallel and operated in parallel, an unused time measuring means for measuring an unused time for each printing unit, and an unused time of each printing unit. And a control unit that preferentially distributes print data to a printing unit having a long unused time among the printing units. 5. A printing apparatus for arranging a plurality of printing units in parallel and operating them in parallel, comprising: an unused time measuring unit for measuring an unused time for each printing unit; For the printing section that exceeded
A printing unit, comprising: a control unit that performs a cleaning process on the printing unit.