JPH09267481A - Ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the consumption amount of ink for the number of printing data and securely prevent cloggings. SOLUTION: A printing head 44 for supplying ink from nozzles to a recording medium and printing is provided in a device, and the flashing operation for jetting ink from all the nozzles of the printing head 44 is carried out periodically. The device is also provided with a cap component for capping the printing head 44 so as to prevent the drying of the nozzles, a passed time measuring means such as a timer 45 or the like for measuring the time having passed based on the last flashing operation and setting the capping time for capping the printing head 44 by the cap component shorter than the actual time, a printer controller 17 for performing the flashing operation when the total of the measured values measured by the passed time measuring means becomes a given value and a head driving section 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for printing by ejecting ink onto a sheet.

[0002]

2. Description of the Related Art In an ink jet recording apparatus, a print head having a large number of nozzles and a paper are arranged so as to face each other, and ink is ejected from nozzles corresponding to output data to the paper while main scanning the print head. According to this, characters and figures are printed on paper. Therefore,
An ink jet recording apparatus that prints by such an operation requires quick drying of the ink so that the ink sprayed on the paper does not contaminate the area other than the sprayed portion, while achieving high-definition print output. Since the nozzle is required to have a small diameter, the nozzle is apt to be clogged due to the coagulation of ink.

Therefore, in the conventional ink jet recording apparatus, when printing is stopped, the print head is capped with a cap member to shut off from the atmosphere so as to prevent clogging due to drying of ink in the nozzle section, and the surrounding area of the nozzle. The atmosphere is kept high humidity. Further, even during printing, if there is a nozzle that is not used for printing for a certain period of time or more, the ink in this nozzle portion dries and becomes clogged. Therefore,
Conventionally, a predetermined time is set within a range that does not cause clogging, the entire time is measured regardless of the presence or absence of capping, and ink is ejected from all nozzles at every predetermined time. A maintenance operation such as a purging operation for sucking and discharging the is carried out, and when a predetermined time has passed during the capping, the maintenance operation is carried out immediately after the capping is released.

[0004]

However, when the entire time is measured regardless of the presence or absence of capping as in the above-mentioned conventional technique, the maintenance operation is performed frequently, so that the amount of ink consumption with respect to the number of print data is increased. There is a problem that Therefore, in order to obtain a desired number of print data, it is possible to store a large amount of ink,
It is necessary to incorporate a large ink cartridge in the recording device, which results in an increase in the size of the recording device.

Therefore, as disclosed in JP-A-3-234639, the time during the capping is excluded from the measurement of the predetermined time, and only the time during which the capping is released is used for the measurement of the predetermined time. Therefore, it is possible to reduce the frequency of maintenance operations. However, the print head is slightly dried even by capping, so that clogging may easily occur due to capping for a long time. Therefore, if the time during capping is completely excluded from the measurement of the predetermined time as described above, there is a problem that clogging may occur between the time when the capping is released and the maintenance operation is performed.

Therefore, the present invention is intended to provide an ink jet recording apparatus capable of reducing the amount of ink consumption with respect to the number of print data and surely preventing clogging.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 is provided with a print head for ejecting ink from a nozzle onto a recording medium to perform printing, and to control the ejection environment of the print head. In an inkjet recording apparatus that regularly performs a proper maintenance operation, a cap member that caps the print head so as to prevent the ink from drying at the nozzles, and the elapsed time from the previous maintenance operation is measured, In addition, the cap time at which the print head is capped by the cap member is a predetermined value that is the sum of the elapsed time measuring means for measuring so as to be a time shorter than the actual time and the measured value by the elapsed time measuring means. And a maintenance means for performing the maintenance operation. Thus, by measuring the cap time in which the nozzle is prevented from drying to be shorter than the actual time, it is possible to extend the maintenance operation interval by judging the measured value by the elapsed time measuring means and the predetermined value. become. Therefore, since the interval of the maintenance operation is expanded in consideration of the drying of the nozzle during capping, it is possible to reduce the amount of ink consumed with respect to the number of print data and surely prevent clogging.

The invention according to claim 2 is the ink jet recording apparatus according to claim 1, wherein the maintenance means comprises:
It is characterized in that it is a flushing means for periodically performing a flushing operation for forcibly ejecting ink from all nozzles of the print head. As a result, it is possible to prevent the ink from drying in the nozzle portion and to recover the meniscus by the flushing operation, so that it is possible to prevent defects such as clogging of the nozzle and dispersion of ejected ink droplets.

The invention of claim 3 is the ink jet recording apparatus according to claim 1, wherein the maintenance means is
It is characterized in that it is a purging means for periodically carrying out a purging operation for sucking and discharging ink from all nozzles of the print head. As a result, much more ink is used as compared to the frassing operation, so that it is possible to recover nozzles that have clogged up, discharge air that has entered the head, etc. Can be prevented.

The invention according to claim 4 is the ink jet recording apparatus according to claim 1, wherein the elapsed time measuring means is
The cap time is measured so that the drying rate of the ink in the nozzle at the time of capping and the drying rate of the nozzle when not exposed to the atmosphere without being capped are the same as the shortening rate. As a result, the cap time is measured so that the drying rate when capping and the drying rate when capping is released match, so it is possible to measure the cap time with the largest reduction rate that does not cause clogging during capping. Therefore, it becomes possible to further extend the interval of the maintenance operation.

According to a fifth aspect of the present invention, there is provided the ink jet recording apparatus according to the first aspect, wherein the ink jet recording apparatus is replaceably mountable with a plurality of types of print heads, and the elapsed time measuring means is mounted. The present invention is characterized by comprising means for discriminating the type of the printed print head, and means for setting a shortening rate according to the ejection performance of the print head and measuring the cap time based on the shortening rate. As a result, the degree to which the clogging is resolved differs depending on the jetting performance of the print head.Therefore, by measuring the cap time at a shortening rate according to the jetting performance and setting the maintenance operation interval, the clogging is more reliable. Can be prevented.

The invention according to claim 6 is the ink jet recording apparatus according to claim 1, wherein the elapsed time measuring means is
It is characterized in that the cap time is measured so that the shortening rate is in accordance with the physical properties of the ink used. As a result, since the drying ratio varies depending on the physical properties of the ink, clogging can be prevented more reliably by measuring the shortening rate according to the physical properties of the ink and setting the interval of the maintenance operation.

According to a seventh aspect of the present invention, in the ink jet recording apparatus according to the sixth aspect, the print head is a head for performing color printing, and the elapsed time measuring means shortens differently for each color of ink. It is characterized in that the cap time is measured at a rate, and the maintenance means performs a maintenance operation for each head of each color according to the measurement value of the elapsed time measurement means. As a result, the optimum maintenance operation interval is set for each print head, and the ink consumption can be reduced under the optimum conditions for each print head.

The invention according to claim 8 is the ink jet recording apparatus according to any one of claims 1 to 7, wherein the elapsed time measuring means divides the real time during which the print head is capped by a predetermined value. This is characterized by measuring the cap time. Thus, the cap time can be measured by software using the arithmetic means that the elapsed time measuring means generally has, so that the shortening rate can be easily changed.

The invention of claim 9 is the ink jet recording apparatus according to any one of claims 1 to 7, wherein the elapsed time measuring means measures the cap time by counting in a predetermined time period. It is characterized by being. Thus, the means for counting the predetermined time period can be easily configured by a logic circuit as hardware, so that the load of software at the time of measuring the cap time can be reduced.

According to a tenth aspect of the present invention, an ink jet recording apparatus is provided with a print head that ejects ink from a nozzle onto a recording medium to perform printing, and periodically performs a maintenance operation for optimizing an ejection environment of the print head. In, a cap member for capping the print head so as to prevent the ink from drying at the nozzle, and a cap time for measuring the elapsed time from the previous recording and capping the print head by the cap member. Is an elapsed time measuring means for measuring the time to be shorter than the actual time, and a maintenance means for performing the maintenance operation when the sum of the measured values by the elapsed time measuring means reaches a predetermined value. It is characterized by having. With this, by measuring the cap time in which the nozzle is prevented from being dried so as to be shorter than the actual time, it is possible to extend the maintenance operation interval by judging the measured value by the elapsed time measuring means and the predetermined value. become. Therefore, since the interval of the maintenance operation is expanded in consideration of the drying of the nozzle at the time of capping, it is possible to reduce the amount of ink consumption with respect to the number of print data and to reliably prevent clogging.

An eleventh aspect of the present invention is the ink jet recording apparatus according to the tenth aspect, wherein the maintenance means is a flushing means for periodically performing a flushing operation for forcibly ejecting ink from all nozzles of the print head. It is characterized by being. This prevents the ink from drying in the nozzle section by the flushing operation,
Since it becomes possible to recover the meniscus and the like, it is possible to prevent defects such as clogging of nozzles and dispersion of ejected ink droplets.

According to a twelfth aspect of the invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the maintenance means is a purging means for periodically performing a purging operation for sucking and discharging ink from all nozzles of the print head. It is characterized by being. As a result, much more ink is used as compared to the frassing operation, so that it is possible to recover nozzles that have clogged up, discharge air that has entered the head, etc. Can be prevented.

According to a thirteenth aspect of the invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the elapsed time measuring means is a nozzle drying rate at the time of capping and a nozzle when the capping is not performed and the atmosphere is opened. So that the shortening rate matches the ink drying rate in
It is characterized by measuring the cap time. As a result, the cap time is measured so that the drying rate when capping and the drying rate when capping is released match, so it is possible to measure the cap time with the largest reduction rate that does not cause clogging during capping. Therefore, it becomes possible to further extend the interval of the maintenance operation.

According to a fourteenth aspect of the present invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the ink jet recording apparatus is replaceably mountable with a plurality of types of print heads, and the elapsed time measuring means is mounted. The present invention is characterized by comprising means for discriminating the type of the printed print head, and means for setting a shortening rate according to the ejection performance of the print head and measuring the cap time based on the shortening rate. As a result, the degree to which the clogging is resolved differs depending on the jetting performance of the print head.Therefore, by measuring the cap time at a shortening rate according to the jetting performance and setting the maintenance operation interval, the clogging is more reliable. Can be prevented.

According to a fifteenth aspect of the present invention, in the ink jet recording apparatus according to the tenth aspect, the elapsed time measuring means measures the cap time so as to obtain a shortening rate according to the physical properties of the ink used. Is characterized by. As a result, since the drying ratio varies depending on the physical properties of the ink, clogging can be prevented more reliably by measuring the shortening rate according to the physical properties of the ink and setting the interval of the maintenance operation.

According to a sixteenth aspect of the present invention, in the ink jet recording apparatus according to the fifteenth aspect, the print head is a head for performing color printing, and the elapsed time measuring means shortens differently for each ink color. It is characterized in that the cap time is measured at a rate, and the maintenance means performs a maintenance operation for each head of each color according to the measurement value of the elapsed time measurement means. This allows
Since the optimum maintenance operation interval is set for each print head, the ink consumption can be reduced under the optimum conditions for each print head.

The invention of claim 17 is based on claims 10 to 1.
7. The inkjet recording apparatus according to any one of 6 above, wherein the elapsed time measuring means measures the cap time by dividing the actual time during which the print head is capped by a predetermined value. . Thus, the cap time can be measured by software using the arithmetic means that the elapsed time measuring means generally has, so that the shortening rate can be easily changed.

[0024] The invention of claim 18 relates to claims 10 to 1.
7. The inkjet recording apparatus according to any one of 6 above, wherein the elapsed time measuring means measures the cap time by counting in a predetermined time period. Thus, the means for counting the predetermined time period can be easily configured by a logic circuit as hardware, so that the load of software at the time of measuring the cap time can be reduced.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 2, the inkjet recording apparatus according to this embodiment is connected to an information processing apparatus 1 such as a personal computer.
The information processing device 1 is used for inputting and instructing data, a processing device main body 2 having a built-in auxiliary storage device such as a magnetic disk device and a central processing unit, a CRT (cathode-ray tube) 3 for displaying data and the like on a screen. It has a keyboard 4 and a mouse 5 and is connected to a printer 7 which is an ink jet recording apparatus via a printer cable 6 of Centronics specification, for example.

As shown in FIG. 1, the processing apparatus main body 2 includes, for example, a window system 8 as an operating system (OS). The window system 8 includes an application 9 such as a document creation program, a font driver 10 for managing fonts, a CRT driver 11 for managing the CRT 3, a keyboard driver 12 for managing the keyboard 4, and a mouse driver 13 for managing the mouse 5. , One or a plurality of applications 9 can be simultaneously executed in cooperation with various functional groups such as the printer driver 14 that manages the printer 7.

The printer driver 14 is capable of forming dot image data when the "print execution" menu is specified for the data displayed on the screen of the CRT 3, for example. Dot data (pixel data arranged in a dot matrix in the horizontal and vertical directions) is formed based on the font data of the text to be displayed, and these dot image data are set in the horizontal direction (raster direction) for each raster. )
Further, the interface (I / F) unit 15 sequentially outputs the print data in units of 8 bits.

The print data output in the raster scan format as described above is input to the I / F (interface) section 16 of the printer 7, which is an ink jet recording apparatus. The printer 7 includes a printer controller 17 (elapsed time measuring means, flushing means), a RAM 18 and a ROM 36 accessible by the printer controller 17, and a head drive unit 1.
9 (flushing means), the CR motor drive unit 20,
It has an LF motor drive unit 33, a timer 45 (elapsed time measuring means) for outputting time data, and an operation panel 46 for instructing various processing operations.

In the RAM 18, various data areas such as a print buffer area for storing print data, a cap time area for storing the cap time Tc, and a cap release time area for storing the cap release time Th are formed. There is. Various processing programs such as a print routine are stored in the ROM 36, and the print routine executes the cap time Tc and the cap release time T described above.
The printing process is performed while determining the interval of the flushing operation using h. The CR motor drive unit 20 and the LF motor drive unit 33 are the CR motor 22 used for main scanning and the LF motor 3 used for sub scanning.
4 and each of these motors 22
-The rotation direction and speed of 34 are controlled.

Further, the head drive section 19 includes the print head 4
4 is connected. Nozzles for ejecting ink by displacement of the piezoelectric elements are arranged in the sub-scanning direction for, for example, 64 channels in the print head 44, and the head drive unit 19 is arranged so that the piezoelectric elements of each channel are displaced. The drive voltage from each is applied. The print head 44 is included in the print head mechanism 21 as shown in FIG.
Has a cartridge holding member 31, an ink supply member 37 provided in the cartridge holding member 31, and an ink cartridge 30 detachably provided in the cartridge holding member 31. Then, the ink supply member 37
The print head 44 described above is replaceably provided in the front part of the printer, and the print head 44 and the ink cartridge 30 are detachable via the cartridge holding member 31.

Inside the ink cartridge 30, the foam 35 having open cells to contain ink is formed.
Is loaded. An ink supply port 30a is formed in the lower part of the front wall (left side wall in the figure) of the ink cartridge 30, and the above-described ink supply member 37 is connected to the ink supply port 30a via a seal member 39. It is fitted tightly. The ink supply member 37 is formed with an ink guide path 37a for communicating the print head 44 with the inside of the ink cartridge 30, and the ink guide path 37a transfers the ink of the ink supply member 37 to the entire print head 44. It is designed to feed channels.

The print head mechanism 2 configured as described above
As shown in FIG. 3, the nozzles 1 are arranged in the main scanning direction X, and are fixed to the carriage 23 so that the ink ejection direction with respect to the paper 25 forms a predetermined angle. Carriage 23
Is movably supported by a guide shaft 24 provided laterally in the main scanning direction X, and is connected to a scanning belt 26 driven by a CR motor 22, and the CR motor 22 driving the scanning belt 26 is By moving the carriage 23 back and forth in the main scanning direction X along the guide shaft 24, the print head mechanism 21 performs main scanning while maintaining a constant distance from the paper 25.

The sheet 25 facing the print head mechanism 21 is supported by a platen roller 28.
The platen roller 28 is provided parallel to the guide shaft 24, and both ends thereof are rotatably supported. A roller gear 29 is fixed to one end of the platen roller 28. A motor gear of the LF motor 34 is meshed with the roller gear 29 via an intermediate gear 40,
The LF motor 34 includes an intermediate gear 40 and a roller gear 29.
The sheet 25 is moved in the sub-scanning direction Y by rotating the platen roller 28 via the above. The movement of the paper 25 in the sub-scanning direction Y is repeated each time the print head mechanism 21 is main-scanned to print one band.

The platen roller 28 sets a printing operation area for printing on the paper 25. Also,
A retracted position of the print head mechanism 21 when printing is stopped is set on one side of the platen roller 28, and a capping mechanism 51 is provided at this retracted position. The capping mechanism 51 includes a cap member 52 having a fitting portion 52a for fitting the print head 44, and a fitting member for moving and fitting the cap member 52 to the print head 44 when the carriage 23 is moved to the retracted position. The capping member 52 caps the print head 44 at the retracted position to prevent the print head 44 from drying. Further, on one side or the other side of the platen roller 28, in order not to overlap with the printing operation area and the retracted position,
A flushing position is set, and at this flushing position, a flushing operation of ejecting ink from all nozzles is performed.

Further, on the lower surface of the carriage 23 on which the print head mechanism 21 is mounted, an encoder element (not shown) composed of a non-contact type sensor such as an optical type or a magnetic type is provided. A timing slit 43 having a large number of slits at equal intervals is provided in parallel with the guide shaft 24 in the detection direction of the encoder element. When the encoder element moves in the main scanning direction together with the carriage 23, The timing slit 43 is detected and output as an encoder signal. And
As shown in FIG. 1, the encoder signal is input to the printer controller 17, and the printer controller 17 stores the print data in the print buffer area based on the encoder signal and performs the writing process and the print process. A read process of reading the print data stored in the buffer area at a predetermined timing and outputting the read print data to the head drive unit 19 is executed.

The operation of the ink jet recording apparatus having the above structure will be described based on the printing routine of FIG.
First, when the printer 7 is turned on, the print routine is executed by the printer controller 17. As a result, the printer controller 17 confirms whether the print head mechanism 21 is in the retracted position as shown in FIG. 3, and if not, moves the print head mechanism 21 to the retracted position. Move and print head 4
4 is capped by the cap member 52 (S1).

Thereafter, the cap time Tc measurement process (T / a) is started at a predetermined reduction rate based on the time data T (real time) from the timer 45 and the correction value a shown in FIG. The measurement process of the release time Th is stopped. That is, the time data T is divided by a correction value a such as “6” to obtain the cap time Tc in the cap time region of the RAM 18.
Only the division value (T / a) is updated, while the cap release time Th before the stop is maintained for the cap release area (S2).

The reason why the cap time Tc shorter than the actual time is obtained by using the value (T / a) obtained by dividing the time data T by the correction value a is that the print head 44 and the atmosphere are capped by capping. This is because the print head 44 is in a state where it is difficult to dry when it is blocked, so that the dry rate at the time of capping becomes a value smaller than the dry rate at the time of releasing the capping and clogging does not occur.

After that, it is determined whether or not the print data from the information processing device 1 is received (S3), and if not received (S3, NO), the process waits while repeating the determination of S3. At this time, in the information processing apparatus 1, when "print execution" is designated by the keyboard 4 or the mouse 5 in FIG.
As shown in FIG. 1, the window system 8 operates the printer driver 14 to output the dot image data created in the raster scan format in the raster order as print data in 8-bit units. When the print data output from the information processing device 1 is received by the printer controller 17 via the I / F unit 16 of the printer 7 (S3, YES), the print data is stored in the print buffer area of the RAM 18. (S4).

When the print data is stored in the print buffer area for n bands (64 rasters × n), the printer controller 17 determines the cap time Tc and the cap release time Th from the cap time area and the cap release time area of the RAM 18. Are read out, and both are added to calculate the flushing interval Tf (S5).

After calculating the flushing interval Tf, the printer controller 17 compares the flushing interval Tf with the set time Ts (for example, 20 seconds) (S6). If the flushing interval Tf is equal to or longer than the set time Ts (S
6, YES), the print head mechanism 21 at the flushing position
Is moved to eject ink from all nozzles of the print head 44 to perform a flushing operation (S7). Then, after the cap time Tc and the cap release time Th are cleared (S8), S9 is executed.

On the other hand, the flushing interval Tf is set to the set time T.
When it is not s or more (S6, NO), S9 is directly executed to start the process of measuring the cap release time Th based on the time data T (real time) from the timer 45 in FIG. The measurement process of the cap time Tc is stopped. As a result, in the subsequent operations, the cap release time T
Only h is updated with the time data T, and the cap time Tc is maintained at the value before the stop (S9).

Next, when the print head mechanism 21 is moved to remove the capping and reaches a predetermined position in the print area, the print data is read from the print buffer area of the RAM 18 and output to the head drive section 19 to output one band. The minute print data is printed (S10). Thereafter, it is determined whether or not the printed band is the read data of the final band, which is the nth band (S11). If the print data of the final band is not read (S11, NO). ), Above S5
And try again. Thus, the flushing interval Tf is calculated and compared with the set time Ts, and if the set time Ts or more, the flushing is performed, while if it is less than the set time Ts, the print data of the next band is read and printed. (S5 to S10). On the other hand, if the print data of the last band has been read (S11, YES), S1
From the cap release time Th while the cap time Tc measurement process is started again after capping is performed.
The measurement process of 1 is stopped, and the reception of print data from the information processing device 1 is awaited (S1 to S3).

In the present embodiment, the cap time Tc and the cap release time Th are cleared immediately after the flushing operation, and the cap release time Th measurement process is started, but one band is printed. The measurement processing may be started immediately after clearing. As a result, it becomes possible to further increase the interval of the flushing operation without causing clogging.

Further, in the present embodiment, the desired shortening rate is obtained by dividing the time data T (real time) by the correction value a and measuring the cap time Tc, but this is not the only option. Alternatively, the shortening rate may be obtained by measuring the cap time Tc with the time data T (real time) and then dividing by the correction value a, or counting in a predetermined time cycle. Then cap time T
The shortening rate may be obtained by measuring c.

Further, the correction value a for determining the above shortening rate
Is preferably determined to be a shortening rate that matches the drying rate of the nozzle at the time of capping and the drying rate at the time of opening to the atmosphere by releasing the capping. Further, the correction value a may be set so as to be a shortening rate according to the ejection performance of the various print heads 44, which is discriminated by a discriminating unit such as a head discriminating sensor or an input switch. It may be set so as to have a shortening rate according to the above.

Further, in the present embodiment, printing is performed by one print head 44, but it is also possible to perform monochrome printing and color printing by a plurality of print heads. It is desirable that the shortening rate be individually determined according to the ejection conditions of each print head and the ink type.

In the above embodiment, the ink jet recording apparatus for regularly performing the flushing operation has been exemplified, but the same can be applied to the ink jet recording apparatus for periodically performing other maintenance operations. For example, it can be applied to an ink jet recording apparatus in which a negative pressure pump is communicated with the capping mechanism 51 and the generated negative pressure is used to periodically perform a purging operation for sucking and discharging the ink in the print head mechanism 21 from all the nozzles.

[0049]

According to the first aspect of the present invention, an ink jet is provided which has a print head for ejecting ink from a nozzle onto a recording medium to perform printing, and which regularly carries out a maintenance operation for optimizing the ejection environment of the print head. In the recording apparatus, a cap member that caps the print head so as to prevent the ink from drying at the nozzle, and a time elapsed from the last maintenance operation are measured, and the print head is capped by the cap member. When the total of the elapsed time measuring means for measuring the cap time that is shorter than the actual time and the measured value by the elapsed time measuring means reaches a predetermined value, the maintenance operation is performed. And a maintenance means. With this, by measuring the cap time in which the nozzle is prevented from being dried so as to be shorter than the actual time, it is possible to extend the maintenance operation interval by judging the measured value by the elapsed time measuring means and the predetermined value. become. Therefore, since the interval of the maintenance operation is expanded in consideration of the nozzle drying during capping, it is possible to reduce the amount of ink consumption with respect to the number of print data and to reliably prevent clogging. Produce an effect.

According to a second aspect of the invention, there is provided the ink jet recording apparatus according to the first aspect, wherein the maintenance means comprises:
It is a configuration that is a flushing unit that periodically performs a flushing operation for forcibly ejecting ink from all nozzles of the print head. As a result, it is possible to prevent the ink from drying in the nozzle portion and to recover the meniscus by the flushing operation, so that it is possible to prevent defects such as clogging of the nozzle and dispersion of ejected ink droplets. Produce an effect.

The invention of claim 3 is the ink jet recording apparatus according to claim 1, wherein the maintenance means is
The purging unit periodically performs a purging operation for sucking and discharging ink from all nozzles of the print head. As a result, much more ink is used as compared to the frassing operation, so that it is possible to recover nozzles that have clogged up, discharge air that has entered the head, etc. It is possible to prevent the non-ejection of the ink.

The invention of claim 4 is the ink jet recording apparatus according to claim 1, wherein the elapsed time measuring means is
The cap time is measured so that the ink drying rate at the nozzle during capping and the nozzle drying rate at the time when the nozzle is not exposed to the atmosphere and exposed to the atmosphere become a shortening rate. As a result, the cap time is measured so that the drying rate when capping and the drying rate when capping is released are matched.
The cap time can be measured at the maximum reduction rate that does not cause clogging during capping, and the maintenance operation interval can be further expanded.

According to a fifth aspect of the present invention, there is provided the ink jet recording apparatus according to the first aspect, wherein the ink jet recording apparatus can replaceably mount a plurality of types of print heads, and the elapsed time measuring means can be installed. And a means for determining the cap time based on the shortening rate, which sets a shortening rate according to the ejection performance of the print head. As a result, the degree of eliminating clogging varies depending on the ejection performance of the print head, so by measuring the cap time at a shortening rate according to the ejection performance and setting the maintenance operation interval,
It is possible to more reliably prevent clogging.

The invention of claim 6 is the ink jet recording apparatus according to claim 1, wherein the elapsed time measuring means is
The cap time is measured so that the shortening rate corresponds to the physical properties of the ink used. As a result, since the drying ratio varies depending on the physical properties of the ink, it is possible to more reliably prevent clogging by measuring the shortening rate according to the physical properties of the ink and setting the interval of the maintenance operation. .

According to a seventh aspect of the invention, there is provided the ink jet recording apparatus according to the sixth aspect, wherein the print head is a head for performing color printing, and the elapsed time measuring means shortens differently for each color of ink. The cap time is measured at a rate, and the maintenance means performs a maintenance operation for each head of each color according to the measurement value of the elapsed time measurement means. As a result, the optimum maintenance operation interval is set for each print head, and thus it is possible to reduce the ink consumption amount under the optimum conditions for each print head.

An eighth aspect of the present invention is the ink jet recording apparatus according to any one of the first to seventh aspects, wherein the elapsed time measuring means divides the real time during which the print head is capped by a predetermined value. By doing so, the cap time is measured. Accordingly, the cap time can be measured by software using the arithmetic means that the elapsed time measuring means generally has, and therefore, there is an effect that the shortening rate can be easily changed.

The ninth aspect of the present invention is the ink jet recording apparatus according to any one of the first to seventh aspects, wherein the elapsed time measuring means measures the cap time by counting in a predetermined time period. It has a structure. As a result, the means for counting the predetermined time period can be easily configured by a logic circuit in hardware, so that it is possible to reduce the load on the software when measuring the cap time.

According to a tenth aspect of the present invention, an ink jet recording apparatus is provided which has a print head for ejecting ink from a nozzle to a recording medium to perform printing, and which regularly carries out a maintenance operation for optimizing an ejection environment of the print head. In, a cap member that caps the print head so as to prevent the ink from drying at the nozzle, and a cap time at which the print head is capped by the cap member by measuring an elapsed time from the previous recording. Is an elapsed time measuring means for measuring the time to be shorter than the actual time, and a maintenance means for performing the maintenance operation when the sum of the measured values by the elapsed time measuring means reaches a predetermined value. It is a structure having. With this, by measuring the cap time in which the nozzle is prevented from being dried so as to be shorter than the actual time, it is possible to extend the maintenance operation interval by judging the measured value by the elapsed time measuring means and the predetermined value. become. Therefore, since the interval of the maintenance operation is expanded in consideration of the drying of the nozzle during capping, it is possible to reduce the ink consumption amount with respect to the number of print data and to reliably prevent clogging. Produce an effect.

According to an eleventh aspect of the invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the maintenance means is a flushing means for periodically performing a flushing operation for forcibly ejecting ink from all nozzles of the print head. It is a certain structure. As a result, it is possible to prevent the ink from drying in the nozzle portion and to recover the meniscus by the flushing operation, so that it is possible to prevent defects such as clogging of the nozzle and dispersion of ejected ink droplets. Produce an effect.

According to a twelfth aspect of the present invention, in the ink jet recording apparatus according to the tenth aspect, the maintenance means is a purging means for periodically performing a purging operation for sucking and discharging ink from all nozzles of the print head. It is a certain structure. As a result, much more ink is used as compared to the frassing operation, so that it is possible to recover nozzles that have clogged up, discharge air that has entered the head, etc. It is possible to prevent the non-ejection of the ink.

According to a thirteenth aspect of the invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the elapsed time measuring means is a nozzle drying rate at the time of capping and a nozzle at the time when the cap is not exposed to the atmosphere. So that the shortening rate matches the ink drying rate in
This is a configuration for measuring the cap time. As a result, the cap time is measured so that the drying rate when capping and the drying rate when capping is released match, so it is possible to measure the cap time with the largest reduction rate that does not cause clogging during capping. become,
It is possible to further increase the maintenance operation interval.

According to a fourteenth aspect of the invention, there is provided the ink jet recording apparatus according to the tenth aspect, wherein the ink jet recording apparatus is replaceably mountable with a plurality of types of print heads, and the elapsed time measuring means is mounted. And a means for determining the cap time based on the shortening rate, which sets a shortening rate according to the ejection performance of the print head. As a result, the degree to which the clogging is resolved differs depending on the jetting performance of the print head.Therefore, by measuring the cap time at a shortening rate according to the jetting performance and setting the maintenance operation interval, the clogging is more reliable. There is an effect that can be prevented.

According to a fifteenth aspect of the present invention, in the ink jet recording apparatus according to the tenth aspect, the elapsed time measuring means measures the cap time so as to obtain a shortening rate according to the physical properties of the ink used. Is. As a result, since the drying ratio varies depending on the physical properties of the ink, it is possible to more reliably prevent clogging by measuring the shortening rate according to the physical properties of the ink and setting the interval of the maintenance operation. .

According to a sixteenth aspect of the present invention, in the ink jet recording apparatus according to the fifteenth aspect, the print head is a head for performing color printing, and the elapsed time measuring means shortens differently for each color of ink. The cap time is measured at a rate, and the maintenance means performs a maintenance operation for each head of each color according to the measurement value of the elapsed time measurement means. As a result, the optimum maintenance operation interval is set for each print head, and thus it is possible to reduce the ink consumption amount under the optimum conditions for each print head.

The seventeenth aspect of the present invention includes the tenth to first aspects.
7. The inkjet recording apparatus according to any one of 6 above, wherein the elapsed time measuring unit measures the cap time by dividing the actual time during which the print head is capped by a predetermined value. As a result, the cap time can be measured by software using the arithmetic means generally possessed by the elapsed time measuring means,
This has an effect that the shortening rate can be easily changed.

The invention of claim 18 relates to claims 10 to 1.
7. The inkjet recording apparatus according to any one of 6 above, wherein the elapsed time measuring means measures the cap time by counting in a predetermined time cycle.
As a result, the means for counting the predetermined time period can be easily configured by a logic circuit in hardware, so that it is possible to reduce the load on the software when measuring the cap time.

[Brief description of drawings]

FIG. 1 is a block diagram of a control system of an inkjet recording apparatus.

FIG. 2 is a perspective view of an inkjet recording apparatus to which an information processing apparatus is connected.

FIG. 3 is a perspective view of a main part of the inkjet recording apparatus.

FIG. 4 is an explanatory diagram showing a state in which the ink cartridge is mounted on the cartridge holding member.

FIG. 5 is a flowchart of a print routine.

[Explanation of symbols]

 1 Information Processing Device 7 Printer 17 Printer Controller 18 RAM 19 Head Drive Unit 20 CR Motor Drive Unit 21 Print Head Mechanism 22 CR Motor 23 Carriage 24 Guide Shaft 30 Ink Cartridge 31 Cartridge Holding Member 33 LF Motor Drive Unit 34 LF Motor 36 ROM 37 Ink Supply Member 38 Actuator Member 44 Print Head 45 Timer 46 Operation Panel 51 Capping Mechanism 52 Cap Member 53 Fitting Mechanism

Claims (18)

[Claims] 1. An ink jet recording apparatus, comprising: a print head for ejecting ink from a nozzle onto a recording medium for printing; and periodically performing a maintenance operation for optimizing an ejection environment of the print head. The cap member that caps the print head to prevent the ink from drying and the elapsed time since the last maintenance operation are measured, and the cap time when the print head is capped by the cap member is the real time. And a maintenance means for performing the maintenance operation when the total of the measured values by the elapsed time measuring means reaches a predetermined value. Characteristic inkjet recording device. 2. The ink jet recording apparatus according to claim 1, wherein the maintenance unit is a flushing unit that regularly performs a flushing operation for forcibly ejecting ink from all nozzles of the print head. 3. The ink jet recording apparatus according to claim 1, wherein the maintenance unit is a purging unit that periodically performs a purging operation for sucking and discharging ink from all nozzles of the print head. 4. The elapsed time measuring means has a shortening rate that matches the drying rate of the ink in the nozzle during capping with the drying rate of the nozzle when the cap is not exposed and is exposed to the atmosphere. The ink jet recording apparatus according to claim 1, wherein the cap time is measured. 5. The ink jet recording apparatus can replaceably mount a plurality of types of print heads, and the elapsed time measuring means determines a type of the mounted print head, and ejects the print head. The inkjet recording apparatus according to claim 1, further comprising: a unit that sets a shortening rate according to performance and measures the cap time based on the shortening rate. 6. The ink jet recording apparatus according to claim 1, wherein the elapsed time measuring unit measures the cap time so as to obtain a shortening rate according to the physical properties of the ink used. 7. The print head is a head for performing color printing, the elapsed time measuring means measures the cap time with a different shortening rate for each ink color, and the maintenance means measures the elapsed time. The inkjet recording apparatus according to claim 6, wherein the maintenance operation is performed for each head of each color according to the measurement value of the measuring unit. 8. The elapsed time measuring means measures the cap time by dividing the real time during which the print head is capped by a predetermined value. The inkjet recording device described. 9. The ink jet recording apparatus according to claim 1, wherein the elapsed time measuring unit measures the cap time by counting in a predetermined time cycle. 10. An ink jet recording apparatus comprising a print head for ejecting ink from a nozzle onto a recording medium to perform printing and periodically performing a maintenance operation for optimizing an ejection environment of the print head, The cap member that caps the print head so as to prevent the ink from drying and the time elapsed from the previous recording are measured, and the cap time when the print head is capped by the cap member is longer than the real time. And a maintenance means for performing the maintenance operation when the total of the measured values by the elapsed time measuring means reaches a predetermined value. Inkjet recording device. 11. The inkjet recording apparatus according to claim 10, wherein the maintenance unit is a flushing unit that regularly performs a flushing operation for forcibly ejecting ink from all nozzles of the print head. 12. The ink jet recording apparatus according to claim 10, wherein the maintenance unit is a purging unit that periodically performs a purging operation for sucking and discharging ink from all nozzles of the print head. 13. The elapsed time measuring means has a shortening rate that matches the drying rate of the nozzle at the time of capping and the drying rate of ink at the nozzle when the nozzle is not exposed to the atmosphere and exposed to the atmosphere. The ink jet recording apparatus according to claim 10, wherein the cap time is measured. 14. The ink jet recording apparatus can replaceably mount a plurality of types of print heads, and the elapsed time measuring means determines a type of the mounted print head, and ejects the print head. 11. The inkjet recording apparatus according to claim 10, further comprising: a unit that sets a shortening rate according to performance and measures the cap time based on the shortening rate. 15. The ink jet recording apparatus according to claim 10, wherein the elapsed time measuring unit measures the cap time so as to obtain a shortening rate according to the physical properties of the ink used. 16. The print head is a head for performing color printing, the elapsed time measuring means measures the cap time with a different shortening rate for each ink color, and the maintenance means uses the elapsed time. The ink jet recording apparatus according to claim 15, wherein the maintenance operation is performed for each head of each color according to the measurement value of the measuring unit. 17. The cap time is measured by dividing the elapsed time measuring means by dividing a real time during which the print head is capped by a predetermined value. The inkjet recording device described. 18. The ink jet recording apparatus according to claim 10, wherein the elapsed time measuring unit measures the cap time by counting in a predetermined time period.