JPS63252748A - Clogging prevention device of liquid injection recorder - Google Patents

Abstract

PURPOSE:To eliminate unnecessary ink consumption and thereby prevent clogging in each nozzle for recording liquid properly by providing a counter to count the number of discharged dots for each nozzle of a printing head and adjusting the number of unloaded discharges for prevention of clogging depending on the content of the counter without deterioration of recording efficiency. CONSTITUTION:A counter (a) is provided which counts the number of discharges per nozzle individually on the basis of a recording signal which drives a nozzle (e). A control means (d) causes the nozzle (e) to be moved to a position outside a recording area by driving a carriage (f) in accordance with the results of comparison by a comparison means (c). Then, a propery amount of recording droplets (ink droplets) is permitted to be discharged from only the nozzle whose number of discharges is below a predetermined value, thus preventing the liquid ink from solidifying and clogging in the nozzle. The afore-mentioned proper amount of the recording droplets is in inverse proportion to the number of discharges. The position outside the recording area is, for instance, the position of a capping device for preventing of clogging.

Description

Detailed Description of the Invention: [Industrial Application Field] The present invention is directed to a solution to clogging of a liquid jet recording device that records information on a recording medium by ejecting recording droplets from a nozzle in response to a recording signal. Regarding prevention devices.

[Prior art] Conventionally, flying liquid is ejected from multiple nozzles (multi-nozzles) provided on a spatula i~ mounted on a gear ridge that moves in the horizontal main scanning direction in response to a recording signal. , on-demand printers that feed paper in the vertical sub-scanning direction, bubble sheet serial dot printers, and Rix ink sheet printers are generally known.

Conventionally, this type of apparatus generally uses a cap-like head capping mechanism to prevent ink from sticking inside the nozzle during standby when no recording is being performed.

[Problems to be Solved by the Invention] However, in the conventional apparatus, during recording, due to the multi-nozzle configuration, depending on the printed content, some nozzles are rarely used or some nozzles are ejected infrequently. If the cap of the capping mechanism is removed and the nozzle is exposed to the atmosphere for a certain period of time without ejecting ink, or if the number of ejections is very small, the moisture in the ink inside the nozzle may evaporate and become ink. It is known that it can stick and cause clogging, causing non-discharge. Therefore, even if printing is in progress, the head must be returned to the double cap position (standby position) once at predetermined time intervals of 5 seconds to several minutes, and all nozzles are driven. It was necessary to prevent clogging by discarding the old ink in the nozzles into the cap and constantly filling all nozzles with new ink that does not have the possibility of sticking. However, if you perform idle ejection by driving all the nozzles at regular intervals, there are serious drawbacks such as the printer's printing throughput may drop and the amount of ink consumed increases, increasing running costs. there were.

Therefore, the present invention provides a liquid that can eliminate the above-mentioned conventional drawbacks, eliminate wasteful consumption of ink, and appropriately prevent clogging in each recording liquid nozzle without reducing recording efficiency. The purpose is to provide a clogging prevention device for a jet recording device.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a liquid jet recording apparatus that records information by ejecting recording droplets onto a recording medium from a plurality of nozzles in accordance with a recording signal. , a counter that individually counts the number of ejections for each nozzle based on the recording signal, a timer that measures the time from when the cap of the nozzle is released or from the end of ejection that is not used for recording, and a counter that counts the number of ejections for each nozzle based on the recording signal. a comparison means for comparing the number of ejections for each nozzle obtained from a counter with a predetermined value, and a nozzle is moved to a position outside the recording area according to the comparison result of the comparison means, The present invention is characterized by comprising a control means for ejecting an appropriate amount of recording droplets from the nozzle for the number of times of ejection.

[Function] The present invention provides a counter for counting the number of ejected dots for each nozzle of the head, and adjusts the number of times empty ejection is performed to prevent clogging (prevention of sticking) according to the contents of the counter. Therefore, it is possible to reduce the amount of ink that is unnecessarily ejected, and it is possible to reduce throughput and running costs.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the basic configuration of an embodiment of the present invention. In this figure, a is a counter that individually counts the number of ejections for each nozzle based on the recording signal that drives the nozzle e.

b is a timer that measures the time from the time when the cap of the nozzle e is released or from the end of ejection not used for recording. C is a comparison means that compares the number of ejections for each nozzle obtained from the counter a in response to the time-up of the timer b and a predetermined value (reference value). d is a control means, which drives the carriage ridge f to move the nozzle e to a position outside the recording area according to the comparison result of the comparison means C, and causes the nozzle e to eject a number of times less than the above-mentioned predetermined value. To discharge an appropriate amount of recording droplets (ink droplets) only from the nozzle, thereby preventing the ink liquid from sticking inside the nozzle and causing clogging.

Note that the appropriate amount mentioned above is inversely proportional to the number of times of ejection. Further, the position outside the recording area is, for example, the position of a capping device for preventing clogging.

FIG. 2 shows a circuit configuration of an embodiment of the present invention. In this figure, 1 is a microprocessor (hereinafter referred to as MPII) that controls the printer operation according to the control procedure shown in FIG. 4, which is stored in an internal memory (ROM).
It is. 2 is a 1-data detection circuit that generates a clock when the digital image data sent from a post system such as an external image reading device or character editing device (prosser) is 1'° in binary; is a discharge dot counter (hereinafter referred to as a counter) which counts up the number of discharges from each nozzle according to the clock of the detection circuit 2. 4 is a shift register that converts serial image data into parallel data, 5 is a RAM (random access memory) that temporarily stores parallel data for one line equal to the number of head nozzles in the vertical direction, and 6 is a shift register that converts the contents of RAM 5 to the vertical direction of the print head. Lateral aperture converter (hereinafter referred to as I) that converts data in the direction (vertical direction)
(referred to as an IV converter). 7 is a register that temporarily stores the data for the number of nozzles of the manually input head from the IIV converter 6 and sends the recorded data to the print head; 8 is a register 4 in the vertical direction;
Print head with 8 nozzles, 9 is printing spatula l-8
This is a timer (so-called time circuit) that measures the time during which the printer is exposed to the atmosphere (that is, the printing time).

FIG. 3 shows a schematic configuration example of the main parts of an ink sheet printer to which the present invention can be applied. In this figure, 30 is a head capping mechanism (hereinafter referred to as a cap) for preventing ink from sticking in the print head 8.

Next, an example of the operation of the embodiment of the present invention will be described with reference to flowchart 1 in FIG. In the above configuration, first, when one line of serial image data in the main scanning direction is transferred from the post system in response to a recording start instruction, the one data detection circuit 2 does not indicate ejection data in the image data. 1
Recognizing this, the counter 3 is incremented by one.

At the same time, the above-mentioned serial image data is converted into abet (bit) parallel data by the shift register 4 and temporarily stored in the RAM 5. In this way, when data transfer for one line is completed (step Sl),
The MP old reads the contents of the counter 3 and stores them in the internal memory (RAM) IB as the ejection dots of the first point (step S2).

Thereafter, the processing operation for image data for the number of head nozzles is repeated in the same way, and in this example, one line data for 48 nozzles is
AM5 and the number of ejected dots for each nozzle is stored in RAMIB (step S3). At this point, the cap 30 is removed from the print head 8 to enable printing, and the timer 9 starts timing operation (step S3). S4
). Next, the old MP moves the print head 8 mounted on the carriage in the horizontal main scanning direction by driving the carriage motor (step S5), and when it reaches the print start position (
Step S[il] The UV converter 6 converts the data arranged in the main scanning direction of the RAM 5 to the vertical spatula 1 to nozzle direction (vertical sub-scanning direction) and transfers it to the register 7 (Step S7) When the data transfer of the number of nozzles to the register 7 is completed (step S8), the nozzles of the print head 8 are driven according to the data contents to print one column of record data (steps 59 and 510).

The above operation is repeated up to the number of columns for one line in the horizontal main scanning direction, and when 48 lines have been printed, the timer 9 determines whether the preset specified time has not been exceeded. (Step 511) If the line has not been exceeded, the data of the next line is input again and the same operation as described above is repeated. However, at this time, the number of ejection data for each nozzle is added to the internal RAMIB (step 5
12). If the contents of timer 9 exceed the specified time, press R.
Determine whether or not the number of times of ejection data for each nozzle up to that point added in AMII'1 has all reached a certain number of times or more at which sticking cannot occur (step 513);
If all nozzles have reached that number, the printing operation continues, but the current ejection data count value in RAMIB is cleared, and the timer 9 is restarted (step S+<).

However, if there are at least one nozzle that does not reach a certain number according to the judgment for RAMIB, print head 8
is moved to the position of the cap 30 (step 515).
, the nozzles whose number has not yet reached a certain number are ejected to eject the necessary amount of ink calculated from the number of ejection data of the nozzles (step 816) into the cap 30 (step 517). At this time as well, the ejection data counter (RAM) 1B of each nozzle is cleared, the timer 9 is restarted (step 518), and manual input and printing of the next data is started.

In the above embodiment, the case where image data is sent serially in the main scanning direction is shown, but this is an example of the circuit configuration of the present invention when general data is input and printed by the printer's own font processing. is shown in Figure 5.

In this figure, jO is a character generator (hereinafter referred to as CG) that stores character and graphic image data ()] gutter pattern data) in a dot configuration.
, 1] is a RAM that temporarily stores 1-1 scan of the data developed by CGIO into the corresponding image (phone 1-pattern) through MPIII, and +2 prints the contents of RAMII. spatula)~
This register stores the number of nozzles (29). Also,
13 to 20 are 1'° data (hereinafter referred to as 1) indicating ink ejection when transferring data to MPIII or RAMII.
1 data detector that detects data (referred to as "data") and generates a clock; 21 to 28 are counters that count the number of words of ejection data corresponding to each nozzle of the print head 29 based on a human clock; 29 is a vertical direction (sub-scanning direction); ) is a print head equipped with 8 nozzles.

In the above configuration, the MP old refers to the CGIO and creates image data (21-int pattern data) according to the 2-1 data sent from the post system. At this time, image data bit strings are arranged in the CGIO in the vertical direction in the same direction as the head 29. In the old MP, one line of this image information is written in the RAM II, and at the same time, one data detector 13 to 20 corresponding to each filler 1 to 1 of the written image information should be ejected to each counter 21 to 28 for each head nozzle. (Tora) ~Write and add numbers. In the embodiment shown in Fig. 2, each nozzle does not have a counter, and the count result of the counter is stored and added to one line in MPIII or internal memory ltAMIB, but in the embodiment shown in Fig. 5, A heart-like counter is provided for each nozzle. Since the following ejection sequence (control procedure) for printing and preventing ink sticking is almost the same as that shown in FIG. 4, detailed explanation thereof will be omitted.

[Effects of the Invention] As explained above, according to the present invention, a counter is provided for each nozzle of the head to count the number of ejected dots, and depending on the contents of the counter, empty ejection is performed to prevent clogging (prevention of sticking). Since the number of times this is performed is adjusted, it is possible to reduce the amount of ink that is unnecessarily ejected, resulting in the effect of reducing throughput and running costs.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the basic configuration of an embodiment of the present invention, Fig. 2 is a block diagram showing the circuit configuration of an embodiment of the invention, and Fig. 3 is a main part showing the external appearance of an embodiment of the invention. FIG. 4 is a flowchart showing the control operation procedure of the embodiment of the present invention shown in FIG. 2, and FIG. 5 is a block diagram showing the circuit configuration of another embodiment of the invention. 1...MPLI. 2... Discharge data detection circuit (1 data detection circuit), 3... Discharge data counting counter, 8.29... Print head, 9... Timer, 10... Character generator, 13... 20... Discharge data detection circuit (1 data detection circuit), 21-28... Discharge data counting counter, 30...
Spatula 1 ~ Capping mechanism. Year Tough (U T Yachi I row/) times Figure 5 Table 0 Follow diagram

Claims (1)

[Scope of Claims] 1) a) A liquid jet recording apparatus that records information by ejecting recording droplets onto a recording medium from a plurality of nozzles in accordance with a recording signal, b) a method for recording information based on the recording signal. a counter that individually counts the number of ejections for each nozzle; c) a timer that measures the time from when the cap of the nozzle is released or from the end of ejection that is not used for recording; and d) when the timer times out. e) a comparison means for comparing the number of ejections for each nozzle obtained from the counter with a predetermined value, e) moving the nozzle to a position outside the recording area according to the comparison result of the comparison means; A clogging prevention device for a liquid jet recording apparatus, comprising: a control means for ejecting an appropriate amount of the recording droplets from a nozzle whose number of ejections is equal to or less than the predetermined value. 2) A clogging prevention device for a liquid jet recording apparatus according to claim 1, wherein the appropriate amount ejected by the control means is an ejection amount inversely proportional to the number of times of ejection. 3) A clogging prevention device for a liquid jet recording device according to claim 1 or 2, wherein the position outside the recording area is the position of a capping device for clogging prevention. .