JPH03173653A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To maintain high quality and high speed printing operation even for long time printing or under high temperature by arranging caps or brushing mechanisms, delivering or sucking very small amount of ink from a head nozzle for printing operation longer than a predetermined time, at plural points in the moving zone of carriage. CONSTITUTION:Upon receiving of a print signal, a carriage 16 moves into a printing area thus keeping up printing operation. Upon elapse of predetermined time set in a timer, refresh operation takes place and printing operation is carried out untill the carriage 16 arrives the left end then a very small amount of ink is delivered toward the belt part of a cleaner 24 located at the left end. When the print signal is further provided and a predetermined time set in a capping timer elapses, printing operation is interrupted upon completion of a line of printing. Capping is performed through a right end suction cap 4' if the stop position of the carriage 16 is at or close to the right end, through a left end cap 4 if the stop position is at or close to the left end, and through a cap in the printing direction prevailing before stoppage of the carriage 16 if the stop position is in the central part. By such arrangement, moving time of carriage required for capping operation can be shortened.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an inkjet recording device.

[Conventional technology 1] In conventional inkjet recording devices, when bit image printing such as Kanji characters or fill-in is performed immediately after consecutive printing of characters such as ANK characters that require a large number of unused nozzles, the number of unused nozzles is The ink dries and missing dots occur.

For this reason, a refresh operation in which about 1 Odat of ink in the nozzle is periodically ejected within a time period during which the ink in the nozzle does not thicken due to evaporation of water, and a capping operation in which the ink in the nozzle is sucked at a certain time have been carried out. (Hereinafter, the discharge operation will be referred to as a refresh operation, and the suction operation will be referred to as a capping operation.) [Problem to be Solved by the Invention 1] However, in the refresh operation and capping operation of the prior art described above, as shown in FIG. 5(a), , when the suction cap 4 is attached to the left end of the printing area, when a signal is received when the carriage 16 carrying the inkjet head l is on the right side and one of the operations is selected, the time required for these operations is the suction cap 4. The movement of the carriage to the left side of a certain printing area is delayed by a time T;
The same applies when the suction cap 4 is located at the right end of the printing area. As shown in Fig. 5(c), when the time of each operation is managed by temperature, the frequency of refresh and capping operations is low at temperatures where evaporation is slow, but the frequency of these operations is high in high-temperature environments where evaporation is rapid, and printing is The time during which the carriage is not being performed (travel time TXn of the carriage (number of refresh operations and capping operations)) increases,
This makes it impossible to achieve the high-speed printing that is a feature of inksheet printers.

The present invention is intended to solve these problems, and its purpose is to provide inkjet recording with stable high print quality even under long-term printing and extremely dry high-temperature environmental conditions, and which does not affect printer speed. The goal is to provide equipment.

[Means for Solving the Problems 1] The ink jet recording apparatus of the present invention includes a carriage on which an ink jet head having an ink jet nozzle is mounted, and a cap mechanism for covering the nozzle portion within a movement range of the carriage or the above. Inkjet recording that has a brushing mechanism that selectively contacts the nozzle part, activates a timer from the start of printing, and automatically ejects or sucks a minute amount of ink from the nozzle of the head when printing continues for a certain period of time. The apparatus is characterized in that the cap mechanism or the brushing mechanism is provided at a plurality of locations within an area in which the carriage moves.

〔Example〕

FIG. 1 shows the brushing mechanism and cap mechanism of the present invention. As shown in FIG. 1(a), the cleaner 24 constituting the brushing mechanism according to the present invention has two blades 24b attached to a rubber belt 24v. This is a mechanism for removing dirt (such as dirt). In the periodic refresh operation of the present invention, a minute amount of ink is ejected from the head 1 onto the belt t-24v portion of the cleaner 24, as shown in FIG. 1(b). The ejected ink is collected by an ink collection mechanism 13 provided on the back side of the cleaner 24 in contact with the belt 24v portion of the cleaner 24, and is collected into the waste ink tank 6 through the tube 31.

The ink recovery mechanism 13 is preferably made of foamed absorbent material or polymeric absorbent material. Furthermore, by integrally molding the ink recovery section and the waste ink recovery section, it can be simplified. As shown in FIGS. 1(c) and 1(d), the cap mechanism consists of a rubber suction cap 4 and two tubes 30 and 30' connected to the cap. A minute amount of ink is ejected into the opening for a refresh operation. Two duplexes 30 connected to cap 4
．． 30', one tube 30 is in cleaning operation;
The other end 30' is connected to an ink pump 5 for a series of suction operations such as capping operations, and the other end 30' is connected to a damper 13. The ink discharged into the suction cap 4 accumulates in an ink reservoir k within the cap, and then enters the ink pump 5 from the ink reservoir k via the tube 30, and is collected from the ink pump 5 into a waste ink tank 6. Further, the ink can be collected into the waste ink tank 6 by driving the ink pump and sucking the ink together with the atmosphere. Here, Figure 1 (b
If the waste ink tanks 6 in ) and (c) are the same, the space can be used effectively.

FIG. 2 shows the configuration of an embodiment of the present invention. An inkjet head 1 having ejection nozzles is connected through an ink flow path 3 to an ink tank 2 containing recording ink. Further, a suction cap 4 that selectively comes into close contact with the nozzle surface is disposed on the entire surface of the nozzle, and an opening/closing mechanism 1O that selectively opens and closes is connected to the suction cap 4.

An ink pump 5 is connected to the suction cap 4 via an ink channel 30, and the pump 5 is connected to a waste liquid tank 6 via an ink channel 31.

The ink flow path 30 branches into ink flow paths 32 and 33 on the way to the pump 5, and the ink flow path 32 is provided with a suction cap 4' in addition to the cap 4, and the ink flow path 33 is provided with a suction cap 4'. An atmosphere release mechanism (valve) 12 is connected. Furthermore, a drive mechanism 9 for operating the ink pump 5
A cleaner 24 is connected to. The cleaner 2
4 is in contact with an ink recovery mechanism 13, and the ink recovery mechanism 13 is connected to the waste ink tank 6 via an ink flow path 31.

On the other hand, the control circuit 8 is wired to the drive mechanism 9 of the pump 5 and the opening/closing mechanism 10 of the suction cap 4. Further, the printer control circuit 11 including the control circuit 8 includes a timer circuit 7.
is provided. As shown in FIG. 2(b), a cleaning mechanism 14 consisting of a cleaner 24 and a suction cap 4 is located at the left end of the platen 23, and a suction cap 4' similar to the suction cap 4 included in the cleaning mechanism 14 is located at the right end. It is provided. The left suction cap 4 is used for normal printing standby, pause operation, cleaning operation, and the like. The suction cap 4' provided on the right side is mainly used for periodic capping operations as a countermeasure against printing defects that occur when characters with a small number of nozzles are printed over a long period of time.

As shown in FIG. 5(b), when a printing signal is input to a control circuit (not shown), the cap 4 is released and the carriage 16 moves to the printing area. If printing continues without interruption, printing will continue until the carriage 16 reaches the left end when the fixed time t1 (1 second to 3 minutes) set in the refresh operation timer is reached, and the belt of the cleaner 24 at the left end will start printing. A minute amount of ink is ejected toward the area, and a print signal continues for a certain period of time t2 (1 minute to 10 minutes) set in the capping timer.
When this happens, printing is interrupted when one line of printing is completed. At this time, as shown in FIGS. 2(c), 2(d), and 2(e), the tiger spear 16 may stop at or near either the left or right edge, or it may stop near the center. If the carriage 16 is stopped at the right end or close to the right end, the right end suction cap 4'
If the stop position of the carriage 1G is at the left end or close to the left end (as shown in FIG. 2nd ward (e)
As shown in , select the cap depending on the direction in which printing was performed before stopping. Therefore, the carriage movement time T2 in the time required for the capping operation can be reduced to less than half of the conventional time. In addition, if the structure shown in Fig. 2 is used, the refresh operation is performed on the belt of the cleaner 24 at the left end, and the capping operation is used at the right end to eject ink into the inside of the suction cap 4. Since it can be done on both ends, it can further reduce the time used for things other than printing. Furthermore, if the control shown in FIG. 5(b) is changed so that the suction cap 4' on the right end performs capping during printing standby, the moving time of the gear ridge 16 is shortened, so that the power can be turned off during movement. The frequency can be reduced and the reliability can be increased.

Another embodiment is shown in FIG. As shown in FIG. 3(a), a cleaning mechanism 14 including a cleaner 24 and a suction cap 4 is provided at the left end of the platen 13, and a cleaner 24' is provided at the right end. The left cleaning mechanism 14 includes a suction cap 4 and a cleaner 24 used for normal printing standby, pause operation, cleaning operation, and the like.

As shown in FIG. 5(b), when a print signal is input to a control circuit (not shown), the nozzle portion of the head is released from the suction cap 4 and the head moves to the print area. As soon as the nozzle part is released from the suction cap 4, a timer in the control circuit is activated.

The time tl that this timer has already recorded in memory
(for example, from 1 second to 3 minutes), the head 1 finishes printing all the data of the line currently being printed, and then moves to the cleaner 24 to eject 10 to 1000 dots of ink per nozzle. At this time, when the head 1 is printing from right to left as shown by arrow A in FIG. When printing is performed from left to right as shown by arrow B in FIG. 3(c), ink is ejected from the cleaner 24' at the right end after printing of that line is completed.

Furthermore, as shown in FIG. 5(b), another timer operates in the same manner as the above-mentioned timer and operates for a set time t2 (for example, 1 minute to 1 minute).
0 minutes) and a capping operation signal is input, no matter where in the printing area head 1 is, printing of the line currently being printed or the next line is completed and head 1 is turned off.
By setting the control so that the capping operation is not performed unless it is at the left end, the time used for purposes other than printing (carriage movement time in refresh operation Tl x number of refresh operations 01 + carriage movement time in capping operation T2 x number of capping operations) n2) can be shortened.

In addition, if the moving range of the carriage is narrowed for the purpose of downsizing the blinker, etc., as shown in FIG. Cap 4 can also be used instead. In this case, normal printing standby state, pause operation, cleaning operation and capping operation, printing area a
When a signal is received, the suction cap 4 at the left end performs a refresh operation, and the cleaner 24' at the right end removes dust, etc. from the front of the head nozzle, and when a signal is already received in the printing area, the cleaner 24' at the right end performs the refresh operation. Furthermore, if a cleaner is not particularly required, by replacing the cleaner 24' on the right end with a 1 2 gap 4' as shown in FIG. 3(e), a normal printing standby state, pause operation, and Cleaning operations, capping operations, and refresh operations can be performed, and time other than printing from the operation of the carriage 16 can be eliminated as much as possible.

In addition, in the arrangement of the brushing mechanism and capping mechanism shown in FIGS. 2 and 3, the structure of the brushing mechanism and capping mechanism is such that the nozzle 40 is The structure is not limited as long as it is larger than the width W of the formed nozzle surface. Furthermore, as for the material, it is possible to use not only rubber but also polymer absorbent material, sponge, etc.

[Effects of the Invention] As described above, according to the present invention, stable, high-quality printing can be obtained even in long-time printing or under high rM/fM conditions with severe drying, and printing that is an advantage of an inksheet printer can be achieved. This has the effect of maintaining high speed.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(d) are configuration diagrams showing embodiments of the present invention. FIGS. 2(a) to 2(e) are diagrams showing embodiments of the inkjet recording apparatus of the present invention. FIGS. 3(a) to 3(e) are diagrams showing embodiments of the present invention. FIGS. 4(a) and 4(b) are diagrams showing the width of the nozzle surface. FIGS. 5(a), 5(b), and 5(c) are diagrams showing conventional examples. ... Ink shet head suction cap cleaner, ink pump, timer circuit, control circuit and above 3 4 379 Ward E square (. Inokun is the best, tohe, 7L゛

Claims (4)

[Claims] (1) A carriage equipped with an inkjet head formed with an ink jet nozzle, and a cap mechanism that covers the nozzle part or a brushing mechanism that selectively abuts the nozzle part within the movement range of the carriage, and starts printing. The inkjet recording device operates a timer from time to time and automatically ejects or sucks a minute amount of ink from the nozzles of the head when printing continues for a certain period of time, the capping mechanism or the brushing mechanism being connected to the carriage. An inkjet recording device characterized in that it is provided at multiple locations within a moving area. (2) The inkjet recording apparatus according to claim 1, further comprising means for ejecting ink to the brushing mechanism. (3) The inkjet recording apparatus according to claim 1, wherein the cap mechanism is also provided with means for ejecting ink. (4) The inkjet recording apparatus according to claim 1, wherein the brushing mechanism is provided with an ink recovery mechanism for recovering ink.