JP2009000911A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet printer in which ink staying in a print head can be discarded into portions other than a maintenance mechanism and the maintenance mechanism can be detached during printing. <P>SOLUTION: The printer includes a platen roller 22, the print head 12 for discharging ink from a nozzle hole toward a printing medium held on the platen roller 22, the maintenance mechanism 13 for cleaning the print head 12, and a discharged ink receiving section 18 for absorbing and retaining ink discharged and discarded by spitting operation from the print head 12. The discharged ink receiving section 18 is placed opposite the maintenance mechanism 13 with the platen roller 22 between them. The discharged ink receiving section 18 includes a replaceably installed absorption pad. When printing is suspended, the print head 12 moves to a position facing the discharged ink receiving section 18 and performs spitting operation to discharge and discard ink in the nozzle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printer, and more particularly to an industrial inkjet printer.

An industrial inkjet printer uses a print head having a width including the print area width of the print medium so that printing can be performed at high speed, and enables printing without moving the print head in the feed direction of the print medium. There is something. However, in order to prevent cleaning of the print head and coagulation of ink in the print head, the print head can be moved in the same direction as the print medium feeding direction so that the maintenance position and the print position can be moved. That is, in an ink jet printer, if ink staying in the print head is left unattended, the ink solidifies and closes the nozzle holes. Therefore, the maintenance mechanism provided at the maintenance position attaches a cap to the print head to prevent the ink from solidifying, and at the end of printing or at the start of printing, sucks out the ink in the nozzle holes by bleeding the air inside the cap. Ink jet printers that clean the print head, such as discharging, have been proposed (for example, Patent Document 1).
JP 2007-90612 A

  For example, in an inkjet printer that is installed in a production line and prints a production date or the like on a product, printing of the inkjet printer may be temporarily interrupted due to the convenience of the line. For example, if the printing stop is continued for 30 seconds or more, the ink staying in the print head may solidify and the nozzle holes may be clogged.

  For this reason, when printing stops for a certain period of time or longer, the print head is transferred to the cap unit in the maintenance mechanism, and the ink staying in the print head is periodically discharged into the cap. This type of operation is called idle discharge operation or spit operation.

  Since it is not known when printing stops due to the convenience of the line, it is avoided to remove the maintenance mechanism (at least the cap unit) during printing. If there is a spit operation while the maintenance mechanism is removed, there is no cap unit that catches the ink ejected by the spit operation, so the ink is ejected inside the printer, which may contaminate the inside of the printer or in some cases the print medium. Because there is. For this reason, it was not possible to remove the maintenance mechanism during printing and perform cleaning or repair. In addition, some printers are provided with a sensor for detecting the position of the maintenance mechanism so that the maintenance mechanism cannot be removed during printing. However, such a printer has an extra cost for the mechanism.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a printer that does not stain the inside of the printer or the print medium even if the maintenance mechanism is removed during printing.

The printer according to the present invention is
A platen that holds the print medium;
A print head having nozzle holes, capable of ejecting ink from the nozzle holes toward a print medium held on the platen, and movable in the same direction as the feed direction of the print medium;
A maintenance mechanism for cleaning the print head;
An ejection ink container that is arranged to be aligned with the maintenance mechanism in the feeding direction and receives and holds ink ejected from the print head by an idle ejection operation;
It is characterized by providing.

  The ejected ink storage unit is constituted by, for example, a pad that absorbs and holds ink ejected from the print head by the idle ejection operation. The pad is preferably replaceable.

  For example, it may further include a control unit that transports the print head to a position facing the ejection ink storage unit at a predetermined periodic timing and ejects the ink.

  For example, the printing head performs a printing operation by ejecting ink toward a printing medium held on the platen, and performs an idle ejection operation for the ink staying in the printing head toward the ejection ink storage unit. It may further comprise a transfer means for transferring between the empty discharge position to be performed and a maintenance position facing the maintenance mechanism.

  The platen is disposed between the maintenance mechanism and the ejected ink storage unit. Alternatively, the ejection ink storage unit may be disposed between the maintenance unit and the platen.

  According to the present invention, in addition to the maintenance mechanism for cleaning the print head, the ejection ink storage portion is provided, so that the ink remaining in the print head during the stop of printing can be discharged without depending on the maintenance means. For this reason, even if the maintenance mechanism is removed during printing, there is no possibility of contaminating the inside of the printer or the printed matter.

  Hereinafter, an industrial inkjet printer according to the best mode for carrying out the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the inkjet printer 1 according to the present embodiment includes a printing unit 10, a transport unit 20, a heating unit 30, and a control unit 40.

  The printing unit 10 stores the print head 12 inside the housing 11 and performs printing by ejecting ink from the print head 12 toward the print medium 50.

  The conveyance unit 20 includes a feed roller 21 and a platen roller 22 that is a platen, and carries the print medium 50 from the A end to the B end. The platen roller 22 is a roller that supports the print medium 50 and holds the print medium 50 in a normal position with respect to the printing unit 10.

  The heating unit 30 is a device that is disposed on the downstream side of the conveyance path of the print medium 50 so as to face the print medium 50 and heats and dries the ink applied to the print medium 50.

  The control unit 40 is a control device including an MPU (Micro Processor Unit) and various memories.

  2 and 3 are cross-sectional views of the printing unit 10 of the inkjet printer 1 shown in FIG. 1, FIG. 2 shows a state in which the print head 12 is in the printing position, and FIG. 3 shows that the print head 12 performs idle ejection operation. The state in the idle discharge position is shown. As shown in FIGS. 2 and 3, the printing unit 10 includes a maintenance mechanism 13, a head carrier 15, a horizontal transfer mechanism 16, a vertical transfer mechanism 17, and a discharge ink storage unit in addition to the casing 11 and the print head 12 described above. 18

  The print head 12 has a substantially rectangular parallelepiped shape, and a nozzle hole (not shown) for discharging ink supplied from an ink cartridge (not shown) is formed on the lower surface (nozzle surface 14) of the print head 12 in the longitudinal direction of the nozzle surface 14 (platen roller). 22 in a direction parallel to the extending direction of 22) at a predetermined interval. The print head 12 has a width including the print area width of the print medium so that printing can be performed at high speed. For this reason, it is possible to print without moving the print head 12 in the extending direction of the platen roller 22 (width direction of the print medium).

  The maintenance mechanism 13 includes a cap unit 131, a wiper unit 132, and a cleaner unit 133. The cap unit 131, the wiper unit 132, and the cleaner unit 133 are the Y direction that is the print medium feeding direction (the direction perpendicular to the direction in which the print head 12 contacts and separates from the platen roller 22 and the direction perpendicular to the extending direction of the platen roller 22). Are arranged in series.

  The cap unit 131 is a device that holds a cap that covers the nozzle surface 14 of the print head 12 and prevents the nozzle holes from drying. The cap unit 131 also has a function of creating a reduced pressure state by extracting air from the cap with a pump (not shown) and sucking and discharging ink in the nozzle holes of the print head 12.

  The wiper unit 132 is a device that scrapes off ink remaining in the nozzle surface 14 after the ink in the nozzle holes of the print head 12 is sucked and discharged by the cap unit 131, and includes a scraper made of rubber or urethane.

  The cleaner unit 133 is a unit that dissolves and cleans the ink remaining on the nozzle surface 14 after the ink is scraped off by the wiper unit 132, and compresses urethane foam or the like impregnated with a cleaning liquid (solvent) that dissolves the ink. It consists of a possible porous body and a case containing the porous body.

  The head carrier 15 is a member that holds the print head 12 so that the nozzle surface 14 faces the platen roller 22.

  The horizontal transfer mechanism 16 and the vertical transfer mechanism 17 move the print head 12 in the horizontal direction (Y-axis direction) and the vertical direction (the Z-axis direction (the direction in which the print head 12 is moved away from and in contact with the platen roller 22)). ), The print head 12 ejects ink toward the print medium 50 held by the platen roller 22 to perform printing, and the ink staying in the print head 12 is ejected to the ink storage unit 18. And a maintenance position in which the cleaning operation is performed by the maintenance mechanism 13 such as the cap unit 131, the wiper unit 132, or the cleaner unit 133. That is, these transfer mechanisms 16 and 17 do not move the print head 12 for printing, but move the print head 12 to a position for maintenance or a position for performing an idle discharge operation by an operation other than printing. It is a transfer mechanism to transfer.

  The horizontal transfer mechanism 16 is fixed to the casing 11, supports the vertical transfer mechanism 17, and transfers the vertical transfer mechanism 17 in the horizontal direction (Y-axis direction). The print head 12, the maintenance mechanism 13, and the discharge ink storage unit 18 are arranged so as to be aligned in the feed direction (Y direction), and the print head 12 is moved to the print position, the maintenance position, and the empty discharge position mainly by the horizontal transfer mechanism 16. Transport.

  The vertical transfer mechanism 17 supports the head carrier 15 and transfers the head carrier 15 in the vertical direction (Z-axis direction (direction in which the print head 12 is brought into contact with and separated from the platen roller 22)).

  The ejected ink storage unit 18 receives and stores ink ejected from the print head 12 in the idle ejection operation, and has a configuration in which the stored ink can be discarded. Desirably, as shown in FIG. 4, the ejected ink storage unit 18 includes a tray 18 a and a sponge-like (porous body) absorbent pad 18 b stored in the tray 18 a. The ejected ink container 18 is separate from the maintenance mechanism 13 and is not affected by the removal of the maintenance mechanism 13. The upper end of the peripheral side wall of the tray 18a is bent in the inner horizontal direction, and functions as a restraining portion 18c that suppresses the absorbent pad 18b. The tray 18 a is slidable along a guide groove (not shown) provided in the housing 11, and can be easily detached from the housing 11. The absorbent pad 18b can be replaced by pulling out the absorbent pad 18b from between the holding portions 18c and inserting it from between the holding portions 18c. The absorbent pad 18b is not limited to a porous body, but may be an absorbent body by chemical reaction, for example, a polymer absorbent body.

  The ejected ink storage unit 18 is disposed in the vicinity of the platen roller 22 on the side facing the maintenance mechanism 13 with the platen roller 22 interposed therebetween. Further, the ejected ink storage unit 18 is disposed such that the upper surface (for example, the upper surface of the absorption pad 18 b) is slightly lower than the upper surface of the platen roller 22. With this arrangement, the print head 12 can be moved from the printing position to the position of the idle ejection operation (hereinafter referred to as the idle ejection position) only by movement in one axial direction by the horizontal transfer mechanism 16, and thereafter Can be returned from the idle ejection position to the printing position.

Next, the operation of the inkjet printer 1 having the above configuration will be described.
The normal printing operation of the ink jet printer 1 is the same as the conventional one, and hereinafter, a description will be given focusing on the idle ejection operation (spit operation) characteristic in the present embodiment.

(1) When the conveyance of the print medium 50 is stopped due to the circumstances of the preceding and following processes, the control unit 40 confirms that the conveyance of the print medium 50 has been stopped by the output of the rotary encoder mounted on the platen roller 22, for example. Determine. In response to this determination, the control unit 40 temporarily stops printing of the inkjet printer 1 and makes the print head 12 stand by at the printing position (maintaining the state of FIG. 2).

(2) The control unit 40 starts a timer (not shown), for example, an internal software timer at the same time as the printing of the inkjet printer 1 is stopped.

(3) When the timer detects that a predetermined time has elapsed (a time that does not solidify the ink in the ink nozzles of the print head 12, for example, 20 to 30 seconds) while the printing is stopped, the control unit 40 The transport mechanism 16 is driven in the Y direction, and the print head 12 is transported immediately above the ejected ink storage unit 18 (empty ejection position) to obtain the arrangement state shown in FIG. As described above, the height of the upper surface of the ejected ink storage unit 18 is lower than the upper surface of the platen roller 22, so that the height of the print head 12 at the printing position and the empty ejection position is the same. Therefore, the print head 12 can be transferred from the printing position to the idle ejection position only by movement in the uniaxial direction (Y direction) by the horizontal transfer mechanism 16.

(4) The control unit 40 performs an idle discharge operation (spit operation). That is, the control unit 40 drives the print head 12 to discharge the ink staying in the print head 12 toward the ejected ink storage unit 18, thereby making the ink in the print head 12 new. The ejected ink storage unit 18 receives and holds the discharged ink.

(5) When the ink discharge (empty ejection) is completed, the controller 40 drives the horizontal transfer mechanism 16 again to return the print head 12 to the printing position, and the state shown in FIG.

(6) When the print head 12 returns to the printing position, the control unit 40 resets the timer and drives the timer again, and the operations from (3) to (6) until the operation of the inkjet printer 1 is resumed. repeat.

  Since there is a limit to the amount of ink that can be absorbed and held by the absorption pad 18b of the ejection ink storage unit 18, the user replaces the absorption pad 18b as necessary or periodically. The absorbent pad 18b can be easily replaced without taking time because the tray 18a is slid and removed from the housing 11, replaced with a new pad, and the tray 18a is slid back into the housing 11. For this reason, there is no problem that the inside of the printer becomes dirty even if it is replaced during printing in which the idle ejection operation is not performed.

  In the ink jet printer 1 having the above-described configuration, since the idle ejection operation is performed on the ejection ink storage unit 18, the maintenance mechanism 13 performs the cleaning of the print head 12 at the start-up or after the printing operation has been stopped for a long time, for example. (Cleaning operation) Dedicated.

  At the time of cleaning at start-up (or after the printing operation has stopped for a long time), the control unit 40 drives the horizontal and vertical transfer mechanisms 16 and 17 to transfer the print head 12 and insert the cap unit 131. Subsequently, the inside of the cap unit 131 is depressurized, and the ink in the print head 12 is sucked.

  Subsequently, the control unit 40 drives the horizontal and vertical transfer mechanisms 16 and 17 to transfer the print head 12 to the wiper unit 132. Subsequently, the control unit 40 drives the wiper unit 132 and scrubs ink adhering to the nozzle surface 14 of the print head 12 with a blade.

  Subsequently, the control unit 40 cleans the nozzle surface 14 by transferring the print head 12 to the cleaner unit 133 and bringing the nozzle surface 14 into contact with a cleaning pad in the cleaner unit 133.

  Further, the control unit 40 transfers the print head 12 to the cap unit 131 when printing is stopped for a long time when the printer apparatus 1 is turned off, and the cap unit 131 is fitted to the print head 12 so that the nozzle surface 14 drying is prevented.

As described above, according to the ink jet printer 1 according to the present embodiment, the ejected ink storage portion 18 is disposed separately from the maintenance mechanism 13, and the ink during the idle ejection operation is absorbed / absorbed by the absorption pad 18 b. The maintenance mechanism 13 can be specialized in cleaning (cleaning) the print head 12. For this reason, even if the maintenance mechanism 13 is removed during printing and the idle ejection operation is performed, the print head 12 does not come to the maintenance mechanism 13, so that the maintenance mechanism 13 can be cleaned and repaired during printing. For this reason, it is not necessary to provide a sensor or a removal prevention mechanism so as not to remove the maintenance mechanism 13 during printing.
Moreover, the absorption pad 18b can be replaced, and the contamination can be prevented. Further, since the work for replacing the absorbent pad 18b is simple and does not take time to replace, the absorbent pad 18b can also be replaced during printing without stopping printing.

In addition, this invention is not limited to the said embodiment, A various deformation | transformation and application are possible.
In the above-described embodiment, the ejection ink storage unit 18 is configured by the tray 18a and the absorption pad 18b. However, the configuration of the ejection ink storage unit 18 receives and accumulates the ink ejected by the idle ejection operation, and is automatically or manually operated. Any configuration can be adopted as long as it can be easily replaced without taking time. For example, it may be configured by a container (tank) that has a receiving port for receiving the ink ejected in an empty manner and stores the ink.

  For example, in the present embodiment, the platen roller 22 is disposed between the cap unit 131 and the discharge ink storage unit 18, but the mounting position of the discharge ink storage unit 18 is not limited to this. For example, the ejected ink storage unit 18 may be disposed so as to be sandwiched between the platen roller 22 and the cap unit 131.

Further, the absorption pad 18b does not need to be maintained at substantially the same height as the platen roller 22, and may be disposed at a position shifted in the Z-axis direction. However, when the print head 12 is moved, movement not only in the Y-axis direction but also in the Z-axis direction occurs.
The configuration of the maintenance mechanism 13 is arbitrary and can be changed as appropriate.
The timing of performing the idle ejection operation is also arbitrary, and may be appropriately selected according to the operating environment of each printer.

  The platen is not limited to the roller-shaped one of the present embodiment, but refers to a member that holds the print medium in a regular position, and is a plate-like one that is cylindrical and does not rotate. There may be.

1 is a schematic cross-sectional view of an ink jet printer showing an embodiment of the present invention. It is sectional drawing of the printing part of the inkjet printer of FIG. 1, and is a figure which shows the state which has a print head in a printing position. It is sectional drawing of the printing part of the inkjet printer of FIG. 1, and is a figure which shows the state which has a print head in an idle discharge position. FIG. 6 is a diagram illustrating a configuration example of a discharge ink storage unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 10 Printing part 11 Housing | casing 12 Print head 13 Maintenance mechanism 131 Cap unit 132 Wiper unit 133 Cleaner unit 14 Nozzle surface 15 Head carrier 16 Horizontal transfer mechanism 17 Vertical transfer mechanism 18 Discharged ink storage part 18a Tray 18b Absorption pad 18c Suppression Section 20 Conveyance section 21 Feed roller 22 Platen roller 40 Control section 50 Print medium

Claims (7)

A platen that holds the print medium;
A print head having nozzle holes, capable of ejecting ink from the nozzle holes toward a print medium held on the platen, and movable in the same direction as the feed direction of the print medium;
A maintenance mechanism for cleaning the print head;
An ejection ink container that is arranged to be aligned with the maintenance mechanism in the feeding direction and receives and holds ink ejected from the print head by an idle ejection operation;
A printer comprising:   The printer according to claim 1, wherein the ejection ink storage unit is configured by a pad that absorbs and holds ink ejected from the print head by an idle ejection operation.   The printer according to claim 2, wherein the pad is replaceable. It further comprises control means for transporting the print head to a position facing the ejected ink storage portion at a predetermined periodic timing and ejecting ink.
The printer according to any one of claims 1 to 3.   A printing position for performing printing by ejecting ink toward the print medium held on the platen by the print head, and an empty space for performing an idle ejection operation for ink staying in the print head toward the ejection ink storage unit. 5. The printer according to claim 1, further comprising a transfer unit configured to transfer between a discharge position and a maintenance position where a cleaning operation is performed by the maintenance mechanism.   The printer according to claim 1, wherein the platen is disposed between the maintenance mechanism and the ejection ink storage unit.   The printer according to claim 1, wherein the ejection ink storage unit is disposed between the maintenance mechanism and the platen.

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