JP2005212433A - Printing apparatus and recording head cleaning method - Google Patents

Abstract

The present invention provides a printing apparatus capable of performing an optimal cleaning process according to the state of an ink jet printing apparatus and removing clogging without wasting ink wastefully.
When a cleaning switch is pressed, a PC value, which is the number of print passes since the previous cleaning, is compared with a threshold value of 400 passes, and if the PC value is equal to or greater than 400 passes, cleaning is performed. When the cleaning process of level CL1 is performed and the value of the PC is less than 400 passes, the cleaning process of cleaning level CL2, which is stronger than the cleaning level CL1, that is, consumes a large amount of ink, is performed.
[Selection] Figure 4

Description

  The present invention relates to an ink jet printing apparatus and a recording head cleaning method.

  2. Description of the Related Art Conventionally, ink jet printing apparatuses that perform printing by discharging ink from a recording head have been developed. This type of printing apparatus requires regular maintenance processing in order to maintain the reliability of the recording head. For example, a mechanism for periodically cleaning the nozzle is prepared in order to prevent the ink from drying up in the nozzles of the recording head and increasing the viscosity to cause a printing failure such as clogging of the nozzles (for example, Patent Documents). 1).

Japanese Unexamined Patent Publication No. 2000-141686 (page 9, FIG. 11)

  By the way, in the conventional ink jet printing apparatus, the cleaning of the nozzles of the recording head not only cleans the nozzle outlets (wiping or rubbing), but also increases the viscosity of the ink in the nozzles and from the ink tank to the nozzles. It is also intended to discharge bubbles and the like in the ink path. Therefore, since ink is sucked from the recording head, a large amount of ink is consumed during cleaning, and a substantial cartridge can be used. There is a problem that the amount of ink decreases, the replacement frequency increases, and costs increase. In addition, the number of used ink cartridges (waste) increases, which is not preferable in terms of resource saving and environmental protection.

  In particular, the cleaning method disclosed in Patent Document 1 has a large amount of ink consumption by providing timer cleaning for repeatedly cleaning the recording head every predetermined time and manual cleaning performed when receiving an instruction from the operator. At the time of manual cleaning, only manual cleaning is not performed when the remaining amount of ink falls below an allowable value, and the amount of ink consumed by cleaning is not reduced. That is, only the ink consumption is different between the timer cleaning and the manual cleaning. In any state, the ink consumption can be reduced by performing a cleaning process at a processing level suitable for the state of the printing apparatus. I'm not trying to keep it low.

  The present invention has been made in view of such circumstances, and a printing apparatus capable of performing an optimal cleaning process in accordance with the state of an ink jet printing apparatus and removing clogging without wasting ink wastefully, and It is an object to provide a recording head cleaning method.

The above object can be achieved by the following method, configuration or program.
(1) A recording head cleaning method for cleaning the recording head by sucking ink from the inside of the recording head that ejects ink, and when a cleaning start instruction is issued, The method includes a step of selecting an optimum cleaning process from a plurality of cleaning processes having different ink consumption amounts in accordance with a difference in the number of scans of the recording head, and cleaning the recording head by the selected cleaning process. .

(2) A recording head cleaning method for cleaning the recording head by sucking ink from the inside of the recording head that ejects ink, and when a cleaning start instruction is issued, If the difference in the number of scans of the recording head is less than a predetermined threshold, the step of performing strong cleaning by sucking more ink than the amount of ink suction in normal cleaning performed when the difference in the number of scans is greater than or equal to the threshold. It is characterized by having.

(3) A printing apparatus including a recording head for ejecting ink, the cleaning instruction means for instructing the start of cleaning, the scan number counting means for counting the number of scans of the recording head, and the cleaning instruction means In response to the difference in the number of scans of the recording head from the previous cleaning start instruction, the most appropriate cleaning process with different ink consumption is selected and selected. Cleaning means for cleaning the recording head in a cleaning process.

(4) In the printing apparatus according to (3), when the cleaning instruction unit instructs the cleaning start, the cleaning unit calculates a difference in the number of scans of the recording head from the previous cleaning start instruction. When the difference in the number of scans of the recording head is equal to or greater than the threshold value compared to a predetermined threshold, normal cleaning is performed by sucking a normal level amount of ink from the inside of the recording head, and the difference in the number of scans of the recording head is If it is less than the threshold value, strong cleaning is performed to suck a larger amount of ink than in the normal cleaning.

(5) A recording head cleaning program used in a printing apparatus having a recording head for ejecting ink, and when a cleaning start instruction is issued, according to a difference in the number of scans of the recording head from the previous cleaning execution Including a procedure for selecting an optimum cleaning process from among a plurality of cleaning processes having different ink consumptions, and cleaning the recording head by the selected cleaning process, and causing the computer to execute the procedure.

(6) A recording head cleaning program for use in a printing apparatus having a recording head for ejecting ink, the number of scans recording procedure for recording the number of scans of the recording head, and the previous cleaning when a cleaning start instruction is issued The number of scans of the recording head from the time is read, and the cleaning condition management table including data obtained by dividing the number of scans of the recording head by a predetermined threshold is referred to, and the time since the previous cleaning start instruction was issued Comparing the difference in the number of scans of the recording head with the threshold, and if the difference in the number of scans of the recording head is equal to or greater than the threshold, performing normal cleaning for sucking a normal level amount of ink from the inside of the recording head, If the difference in the number of scans of the print head is less than the threshold, the normal clear is performed. It includes a cleaning procedure for performing powerful cleaning for sucking the larger amount of ink than during training, and is characterized in that to the the computer execute each step.

  In the recording head cleaning method described in (1) and (2) above, an optimum level of cleaning processing is performed based on the difference in the number of scans of the recording head since the previous cleaning when a cleaning start instruction was issued. Therefore, clogging can be removed without wasting ink. Furthermore, since the ink consumption can be kept low, the frequency of cartridge replacement due to ink consumption is reduced, which can save resources and contribute to environmental protection.

  In the printing apparatus according to the above (3) and (4), when the cleaning start instruction is output, the difference between the number of scans of the recording head at the time of the previous cleaning and the number of scans of the recording head at the start of the current cleaning Based on this, since the optimum level of the cleaning process is selected, clogging can be removed without wasting ink wastefully. Furthermore, since the ink consumption can be kept low, the frequency of cartridge replacement due to ink consumption is reduced, which can save resources and contribute to environmental protection.

  In the recording head cleaning program described in (5) and (6) above, when a cleaning start instruction is issued, the number of scans of the recording head from the previous cleaning is obtained, and the cleaning is performed based on the obtained number of scans. Since a suitable level of cleaning process is selected with reference to the condition management table, clogging can be removed without wastefully consuming ink. Furthermore, since the ink consumption can be kept low, the frequency of cartridge replacement due to ink consumption is reduced, which can save resources and contribute to environmental protection.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments for carrying out the invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing an overview of a printing apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the configuration of the printing apparatus. In the present embodiment, a printer device is taken as an example of a printing device.
The printing apparatus 1 according to this embodiment performs printing based on print data transmitted from the host computer 50 (see FIG. 2), as in a general printer apparatus. The printed recording paper 40 is discharged from the paper discharge port 3 while being placed on the tray 2.

  An operation panel unit 4 is disposed on the front side of the printing apparatus 1, and an LCD (liquid crystal display) 5, a power switch 6, and a cleaning switch 7 are disposed on the operation panel unit 4 as display means. The LCD 5 displays the menu function, operation content, operation status, error content, and the like of the printing apparatus 1. The power switch 6 is pressed when the printer 1 is turned on, and the cleaning switch 7 is pressed when a cleaning process described later is executed manually.

  2, the printing apparatus 1 includes a printer unit 10 that performs printing on a recording paper 40 (see FIG. 1), and a control unit 11 that controls the printer unit 10. The control unit 11 includes a CPU 12, a ROM 13, a RAM 14, an interface unit (I / F unit) 15, and a counter 16, and the interface unit 15 is connected to the CPU 12 through a bus 18. A host computer 50 is connected to the interface unit 15 via a cable (not shown). The CPU 12 controls the printer unit 10 according to a control program stored in the ROM 13. At the time of printing, the CPU 12 drives the printer unit 10 based on print data input from the host computer 50 via the interface unit 15 to execute printing on the recording paper 40.

  The counter 16 is a counter that counts the number of print passes corresponding to the number of scans of a recording head 22 (to be described later) of the printer unit 10 and is counted up each time the recording head 22 scans. Hereinafter, the counter 16 is referred to as a printing pass number counting counter. Further, the count value of the print pass number counter 16 is assumed to be PC. The printer unit 10 includes a carriage 21 that reciprocates in the main scanning direction (a direction orthogonal to the direction in which the recording paper 40 is fed) by the carriage motor 20. The carriage 21 is provided with a recording head 22 at the lower portion thereof, and ink cartridges 23 and 24 (two types for black and color) for supplying ink to the recording head 22 are detachable at the upper portion thereof. It is attached.

  A cap 26 that can seal the nozzle hole 25 of the recording head 22 is disposed at an end portion (home position) of the carriage 21 in the moving direction. A suction pump 27 is connected to the cap 26 via a pump tube 28 for making the internal space of the cap 26 negative pressure when the nozzle hole 25 is sealed by the cap 26. The suction pump 27 is driven by a motor 29, and the ink sucked by the suction pump 27 is absorbed by the waste liquid absorbent 31 inside the waste liquid tray 30.

  Normally, the printing apparatus 1 executes a cleaning process as a work mode in order to eliminate the deterioration in print quality. This cleaning process is performed by forcibly sucking and discharging the ink in the nozzle hole 25 by applying a negative pressure to the inner space of the cap 26 by the suction pump 27 when the nozzle hole 25 is sealed. This is a process of wiping the nozzle plate 22a with a wiping member. By this cleaning process, clogging of the nozzle holes 25 of the recording head 22 and the mixing of bubbles into the ink flow path communicating with the nozzle holes 25 are eliminated.

  The cleaning process is automatically performed when printing is resumed after the printer 1 is stopped for a long time, that is, when a predetermined set time (for example, 2 to 3 days) has passed since the last cleaning process when the power is turned on. In addition, it is performed when the cleaning switch 7 is manually operated or when a cleaning execution button is selected on the screen 51 of the host computer 50. That is, when the CPU 12 determines that the cleaning process is necessary by operating the cleaning switch 7, the power switch 6, the host computer 50, or the like, the CPU 12 drives the motors 20 and 29 to execute the cleaning process. A plurality of types of cleaning processes are set according to the status of the printing apparatus 1. That is, two types of CL1, which is a standard cleaning process, and CL2, which is a cleaning process stronger than CL1, are set.

  The printing apparatus 1 realizes cleaning using two processing levels with different ink consumptions, that is, CL1 and CL2. The amount of ink consumed during these cleanings is CL1 <CL2. In each of the CL1 and CL2 cleaning processes, a process of sucking ink from the nozzle mainly for the purpose of discharging the thickened ink and bubbles in the ink path, and a so-called wiping process of cleaning the head surface with a rubber spatula, If necessary, a so-called rubbing process is performed in which the head surface is removed using a sponge.

  Returning to FIG. 2, the ROM 13 stores a cleaning condition management table 13 </ b> A obtained by converting the above-described cleaning condition table into data. In the cleaning condition management table 13A, data indicating the relationship between the number of printing passes since the previous cleaning and the type of cleaning is recorded. The CPU 12 performs the cleaning process by referring to the cleaning condition management table 13A based on the number of print passes when the cleaning switch 7 is pressed.

  That is, the CPU 12 manages the operation of the switch such as the cleaning switch 7 and the power switch 6 and the number of print passes from the previous cleaning process, and determines the type of cleaning process to be performed when the cleaning condition is satisfied. Identify. After the specification, the CPU 12 refers to the cleaning condition management table 13A in the ROM 13 and selects a cleaning process to be executed. That is, when the cleaning switch 7 is pressed and the number of printing passes since the previous cleaning process is 400 or more, the cleaning process of the cleaning level CL1 is selected, and when the number of printing passes is less than 400, the cleaning level CL2 is selected. Select a cleaning process. Note that when the cleaning switch 7 is first pressed, the number of print passes accumulated since the use of the printing apparatus 1 is started is used.

  Here, FIG. 3 is a functional block diagram of the cleaning process realized by the CPU 12 of the printing apparatus 1. The CPU 12 implements a cleaning switch detection unit 1201, a print pass count unit 1202, a cleaning type selection unit 1203, and a cleaning process execution unit 1204. The cleaning switch detection unit 1201 detects the operation of the cleaning switch 7.

  The printing pass number counting unit 1202 counts the number of scans of the recording head 22 from when the power is first turned on after acquiring the printing apparatus 1, and counts until then when the cleaning switch 7 is pressed. The number of scans performed is output, and once reset, the number of scans is counted again. The cleaning type selection unit 1203 selects a cleaning type based on the number of printing passes (the number of scans) when the cleaning switch 7 is pressed. The cleaning process execution unit 1204 performs the cleaning process of the recording head 22 with the cleaning type selected by the cleaning type selection unit 1203.

  Next, the cleaning processing operation in the printing apparatus 1 will be described with reference to the flowchart shown in FIG. However, as a condition, it is assumed that the cleaning switch 7 has never been operated in the past.

  First, it is determined whether or not the cleaning switch 7 has been pressed (step ST1). If the cleaning switch 7 has not been pressed, another process is executed (step ST2). On the other hand, if the cleaning switch 7 is pressed, the number of printing passes (count value PC of the pass number counting counter 16) from the previous cleaning is obtained (step ST3). As described above, when the cleaning switch 7 is first pressed, the number of print passes accumulated since the use of the printing apparatus 1 is started is used.

  Then, after obtaining the PC value from the previous cleaning process, it is determined whether the PC value is less than 400 passes (step ST4). In this determination, if the value of the PC is equal to or greater than the number of 400 passes, that is, “No”, a cleaning process of the cleaning level CL1 is performed (step ST5). That is, if the cleaning switch 7 is operated after a certain period of time after the previous cleaning process (that is, the clogging is sufficiently eliminated by the previous cleaning process), the cleaning process is performed at the cleaning level CL1. After performing this cleaning process, the PC value obtained this time is cleared (step ST6), and the process returns to step ST1. When the cleaning switch 7 is pressed for the first time, the number of print passes accumulated since the start of use of the printing apparatus 1 is compared with the number of 400 passes. Process.

  On the other hand, if it is determined in step ST4 that the PC value from the previous cleaning process is less than 400 passes, that is, “Yes”, the cleaning process of the cleaning level CL2 is performed (step ST7). That is, if the cleaning switch 7 is pressed again in a short period after the previous cleaning process (that is, the clogging is not sufficiently eliminated by the previous cleaning process), the cleaning is stronger than the previous time, that is, the ink consumption is higher. Process. After performing this cleaning process, the PC value obtained this time is cleared (step ST6), and the process returns to step ST1. When the cleaning switch 7 is pressed for the first time, the number of print passes accumulated since the start of use of the printing apparatus 1 is compared with the number of 400 passes. Process.

  As described above, according to the printing apparatus 1 of the present embodiment, when the cleaning switch 7 is pressed, the number of printing passes (PC value) from the previous cleaning is compared with the number of 400 passes, and the value of the PC is determined. Is equal to or greater than 400 passes, the cleaning process at the cleaning level CL1 is performed. If the PC value is less than 400 passes, the cleaning level CL2 is stronger than the cleaning level CL1 (that is, the ink consumption is higher). Process.

  Accordingly, the optimum one is selected from the two cleaning processes CL1 and CL2 having different ink consumption according to the state of the printing apparatus 1, and the recording head 22 is cleaned by the selected cleaning process, so that the ink is wasted. It is possible to remove the clogging without consuming it. Furthermore, since the ink consumption can be kept low, the frequency of cartridge replacement due to ink consumption is reduced, which can save resources and contribute to environmental protection.

  In the above-described embodiment, two types of cleaning levels CL1 and CL2 are set. However, the cleaning levels are not limited to these and may be further divided. For example, after flushing, the head surface may be cleaned, the head may be capped, the ink may be sucked, and YCL, which is a cleaning process that does not consume ink, may be set.

  In the above-described embodiment, the threshold value used as a criterion for the case of cleaning processing is set to “400”. However, the threshold value is not limited to this value and is arbitrary. That is, the value may be determined according to the state of the printing apparatus 1. Further, a means for arbitrarily setting this value may be added. Of course, when three or more cleaning levels are set, one threshold is insufficient. For example, when three cleaning levels are set, two thresholds are required.

  Further, in the present embodiment, the printing apparatus 1 is a printer apparatus. However, as long as inkjet printing is performed, there is no limitation on the model to be applied.

  The present invention can be applied to a printer or a facsimile machine that performs ink jet printing.

1 is a perspective view showing an overview of a printing apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration of the printing apparatus in FIG. 1. FIG. 2 is a block diagram illustrating a cleaning processing function of the printing apparatus of FIG. 1. 3 is a flowchart illustrating a cleaning process of the printing apparatus in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printing apparatus 4 Operation panel 6 Power switch 7 Cleaning switch 10 Printer part 11 Control part 12 CPU
13 ROM
13A Cleaning condition management table 14 RAM
16 Print Pass Count Counter 20 Carriage Motor 21 Carriage 22 Recording Head 22a Nozzle Plate 23, 24 Ink Cartridge 25 Nozzle Hole 26 Cap 27 Suction Pump 28 Pump Tube 29 Motor 30 Waste Tray 31 Waste Liquid Absorbing Material

Claims (6)

A recording head cleaning method for cleaning the recording head by sucking ink from the inside of the recording head for discharging ink,
When a cleaning start instruction is issued, the optimum cleaning process is selected from a plurality of cleaning processes with different ink consumption amounts according to the difference in the number of scans of the recording head since the previous cleaning. And a step of cleaning the recording head. A recording head cleaning method for cleaning the recording head by sucking ink from the inside of the recording head for discharging ink,
When the cleaning start instruction is issued, if the difference in the number of scans of the recording head from the previous cleaning is less than a predetermined threshold, the ink for normal cleaning performed when the difference in the number of scans is equal to or greater than the threshold A recording head cleaning method comprising a step of performing strong cleaning by sucking ink more than a suction amount. A printing apparatus having a recording head for discharging ink,
Cleaning instruction means for instructing the start of cleaning;
A scan number counting means for counting the number of scans of the recording head;
When a cleaning start is instructed by the cleaning instruction means, an optimum one of a plurality of cleaning processes with different ink consumption amounts is selected according to a difference in the number of scans of the recording head from the previous cleaning start instruction. Cleaning means for selecting and cleaning the recording head in the selected cleaning process;
A printing apparatus comprising:   The cleaning unit compares a difference in the number of scans of the recording head from a previous cleaning start instruction when a cleaning start is instructed by the cleaning instruction unit, and compares the number of scans of the recording head with a predetermined threshold. Is equal to or greater than the threshold, normal cleaning is performed by sucking a normal amount of ink from the inside of the recording head, and if the difference in the number of scans of the recording head is less than the threshold, the cleaning is greater than during normal cleaning. The printing apparatus according to claim 3, wherein powerful cleaning is performed to suck an amount of ink. A recording head cleaning program used in a printing apparatus including a recording head for discharging ink,
When a cleaning start instruction is issued, the optimum cleaning process is selected from a plurality of cleaning processes with different ink consumption amounts according to the difference in the number of scans of the recording head since the previous cleaning. A recording head cleaning program, comprising: a step of cleaning the recording head; and causing a computer to execute the procedure. A recording head cleaning program used in a printing apparatus including a recording head for discharging ink,
A scan count recording procedure for recording the scan count of the recording head;
Read the number of scans of the recording head from the previous cleaning when a cleaning start instruction is issued, and refer to a cleaning condition management table that includes data in which the number of scans of the recording head is divided according to a predetermined threshold, The difference in the number of scans of the recording head from when the cleaning start instruction was issued last time is compared with the threshold, and if the difference in the number of scans of the recording head is equal to or greater than the threshold, the amount of the normal level from the inside of the recording head And a cleaning procedure for performing strong cleaning for sucking a larger amount of ink than that during the normal cleaning if the normal cleaning for sucking the ink is performed and the difference in the number of scans of the recording head is less than the threshold. The above-mentioned steps are executed by the recording head cleaning Program.

Images