JP2006068978A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder which prevents waste ink clogging of a discharge pipe outlet due to waste ink sticking in the vicinity of the discharge pipe outlet in a waste ink tank, and has a stable recovery means. <P>SOLUTION: An air current from a platen suction mechanism and an ink mist suction mechanism is diffused and discharged to the waste ink tank after merged with the waste ink. A region without an ink absorber prepared so as to efficiently diffuse the waste ink is set in the perimeter of a discharge opening. The discharged waste ink is evenly adhered to the absorber of a wide range and is prevented from partial sticking. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an ink jet recording apparatus that performs recording on a recording medium by discharging ink from a recording head.

In an ink jet recording apparatus that forms an image on a recording medium by discharging dye-based or pigment-based ink droplets from the recording head, the recording head in which discharge ports for discharging ink droplets are formed and the recording head are usually mounted. A carriage that reciprocates in a predetermined direction, and a recording medium conveyance device that conveys the recording medium in a direction orthogonal to the predetermined direction (recording medium conveyance direction).

      When an image is formed on a recording medium, the recording medium being conveyed by the recording medium conveying device is temporarily stopped, and the carriage is reciprocated in the predetermined direction, while the ink is based on the image signal carried above the image. Ink is ejected from the ejection ports, and an image for one band is formed on a portion of the recording medium located in the image forming area facing the ink ejection ports. Thereafter, the recording medium is transported by a width corresponding to one band and stopped, and again, the ink droplets are ejected from the ejection port based on the image signal while reciprocating the carriage in the predetermined direction. An image is formed in a portion newly located in the image forming area. By repeating such an operation, an image is formed on the recording medium.

      The ink jet recording apparatus is an extremely excellent printing method having a simple configuration, but has a problem to be solved.

An ink jet recording apparatus discharges when the apparatus is not used for a long period of time, or even when it is used, a specific discharge port rarely discharges compared to other discharge ports. The evaporation of moisture in the ink chamber communicating with the outlet or the ejection port may increase the viscosity of the ink, resulting in ejection failure.

However, conventionally, in order to prevent such a situation, a recovery device that forcibly sucks ink from the ejection port and restores the ink ejection state to the initial state has been used.

In this recovery device, the inside of the ejection port is cleaned by covering (capping) the ejection port of the recording head with a cap made of rubber or the like, generating negative pressure from the outside, and sucking out ink from the ejection port. As a result, ink is sucked from the ejection port, and the ink ejection state is restored to the initial normal ejection state. The ink sucked by the recovery device at the time of cleaning is stored in the waste ink tank as waste ink.

The ink that flows into the waste ink tank has a plurality of inks such as magenta, cyan, and yellow in addition to black in an ink jet recording apparatus that can record a color image. From the viewpoint, the type of black ink and color ink was changed, that is, the black ink may employ pigment-based ink, and the color ink may employ dye ink. It has a pigment system, caps for each, and discharge recovery means. In this case, black ink discharge recovery and color ink discharge recovery are performed separately, and each ink is discharged from an individual discharge port, and the positions of the discharge ports are arranged separately. .
JP2002-225313

      Due to the nature of the pigment ink, it is much easier to fix than the dye ink, so the pigment ink is fixed around the waste ink discharge port of the discharge pipe that discharges the pigment ink sucked by the discharge recovery means as shown in Fig. 1. As a result, the waste ink discharge port is closed and the discharge recovery performance deteriorates.

      In order to solve such a problem, the present invention sucks ink mist by a suction mechanism for sucking a platen, for example, on a paper transport of a recording medium, by various suction means functionally provided in the ink jet recording apparatus. The exhaust pipe through which airflow generated by a suction mechanism such as a fan and the waste ink discharge pipe through which waste ink discharged by the recovery means of the recording head is coupled by a coupling member before the waste ink discharge port, Waste ink is scattered by ejecting and discharging waste ink to a waste ink tank. By doing so, the scattered ink does not stay directly under the outlet of the waste ink discharge pipe but is absorbed from the surface layer of the waste ink absorber in the waste ink tank.

Further, by arranging a one-way valve between the recovery means and the pipe joining member, the backflow of the airflow to the recovery means is prevented, and the waste ink discharged by the recovery means of the recording head is placed on the flow of the airflow to be waste ink. Can be sent to the tank.

      As described above, according to the present invention, there is a stable recovery means that can prevent ink clogging due to the pigment-based ink adhering to the vicinity of the discharge pipe of the waste ink tank and depositing it, and can maintain discharge recovery performance. An ink jet recording apparatus can be provided.

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

A plotter as an example of the ink jet recording apparatus of the present invention will be described with reference to FIG. FIG. 2 is a perspective view showing a schematic configuration of the plotter.

  FIG. 1 is a perspective view showing a schematic configuration of a plotter as viewed from the front.

      The plotter 10 includes a platen 14 on which a recording medium 12 conveyed in the direction of arrow A is placed. The platen 14 is provided with a platen suction fan (not shown) for sucking the recording medium 12. Two scanning rails (guide rails) 16 are spanned above the platen 14 in parallel to the platen 14. A carriage 20 that reciprocates in the directions of arrows B and C (directions orthogonal to the direction of arrow A) by a motor (not shown) and a belt 18 is attached to the scanning rail 16 via a slide bearing (not shown). Yes.

The carriage 20 is equipped with four recording heads 20Bk (black), 20C (cyan), 20M (magenta), and 20Y (yellow) having ink discharge ports (nozzle outlets, not shown) for discharging ink. Has been. In front of the ink ejection opening is an image forming area 23 where an image is formed. Ink is ejected from the ink ejection port to a portion of the recording medium 12 located in the image forming area 23, whereby an image is formed in this portion.

In a corner of the movable range of the carriage 20 away from the image forming area 23, ink is forcibly sucked from the nozzles, and the ink supply path and nozzles formed on the recording head 22 are cleaned and recorded. A recovery device 30 is provided that changes the ink discharge state of the head 22 to the initial discharge state.

In forming an image on a recording medium 12 such as roll paper, the recording medium 12 was placed on the platen 14 and a part of the outer peripheral surface was exposed from an opening (not shown) formed in the platen 14. The recording medium 12 is conveyed by rotating the conveying roller 24 by a motor (not shown) while sandwiching the recording medium 12 by the conveying roller 24 and the pinch roller 26 that presses both ends of the recording medium 12 from above. The carriage 20 is reciprocated in the directions of arrows B and C above the recording medium 12 to generate image signals carrying image information transmitted from the head control unit (not shown) to the print heads 22Bk, 22C, 22M, and 22Y. Based on this, ink is ejected from the nozzles, and an image is formed on the portion of the recording medium 12 located in the image forming area 23. During the image forming operation, when it becomes necessary to suck ink from the nozzles in order to clean the nozzles, the carriage 20 is moved above the recovery device 30. When the image formation is completed, a cutter (not shown) mounted on the carriage 20 is ejected to a predetermined position, and the recording medium 12 is cut into a predetermined size.

The recovery device 30 includes four caps 32Bk, 32C, 32M, and 32Y made of rubber that detachably cover the outlets of the nozzles of the four print heads 22Bk, 22C, 22M, and 22Y. One end of a tube (not shown) is connected to each cap 32Bk, 32C, 32M, 32Y, and the other end of this tube is gathered together in the middle via a suction pump (not shown). (Not shown). The four caps 32Bk, 32C, 32M, 32Y are fixed to the cap base 32.

In recent years, the number of ejection ports of the recording head 22 has increased due to the improvement in printing resolution and high-speed printing, and an ink mist suction fan (not shown) for sucking ink mist generated during printing that has increased due to the increase. An ink mist collection mechanism is provided.

FIG. 3 is a schematic diagram of one embodiment.

An exhaust pipe 42 through which airflow generated by a platen suction mechanism such as a fan for sucking the recording medium onto the platen on the paper transport, a suction mechanism (not shown) such as a fan for sucking ink mist, and discharge recovery means That is, the waste ink discharge pipe 41 through which the waste ink discharged by sucking the ink by the suction pump 45 is connected to the recording head 22 by the connecting portion 44 and the waste ink discharge pipe 41 is connected to the waste ink. A discharge pipe 43 in which ink and airflow are mixed is held in a waste ink tank 47. At this time, a one-way valve 46 is provided between the suction pump 45 and the coupling portion 44 so that the air flow generated by the suction mechanism does not flow to the discharge recovery pump 45 side, and is opened only when the waste ink is discharged to the waste ink tank 47. ing. Note that the airflow generated by the platen and the ink mist suction fan flowing in the exhaust pipe 42 in such a mechanism may be an airflow obtained by combining the airflows, or only one of each may be used. .

FIG. 4 is a perspective view of the waste ink tank section.

The waste ink tank 47 may be a container having a shape as shown in FIG. 4 or may have another shape (not shown). The waste ink tank 47 is made of industrial plastic, metal or the like. A waste ink absorber 48 is accommodated in the waste ink tank 47 as waste ink holding means. The waste ink tank 47 is provided with a rubber holding material 49 for holding the waste ink and exhaust discharge pipe 43 in the waste ink tank 47 at a portion located at one end of the side wall. Further, the attachment position of the discharge pipe 43 may be either the side surface or the top face of the waste ink tank 47, and the discharge pipe outlet may be a single pipe or a plurality of discharge pipes as shown in FIG. In this arrangement, the waste ink absorber 48 is discarded to the extent that the absorption capacity is not reduced.

A space is provided around the outlet of the discharge pipe 43 from which the ink and the air current are discharged, so that the scattering of the ink spreads and the absorption to the surface layer of the waste ink absorber 48 is improved. Furthermore, the absorber of another shape like FIG. 6 may be sufficient.

Further, the airflow sent through the exhaust pipe 42 is an airflow generated by a suction mechanism such as a platen suction fan or an ink mist suction fan. Ink is contained in a mist state, passes through the exhaust pipe 42, and passes through the exhaust pipe 42 to be a waste ink discharge pipe 41. Are connected to the waste ink tank 47, so that it is not necessary to provide a waste ink tank for platen suction or ink mist suction, leading to cost reduction.

In this way, when the pigment-based ink flows alone by scattering the ink and absorbing it by the ink holding means, it is possible to prevent ink clogging by adhering to and depositing in the vicinity of the waste ink discharge pipe. By efficiently absorbing the waste ink into the absorber of the waste ink tank, it is possible to have a stable recovery means that can maintain the discharge recovery performance.
The plotter 10 is fixed to the upper part of a stand 12 with casters 12a. The plotter 10 includes an operation unit 14 for operating the plotter 10, and the paper size, online / offline, command, and the like are instructed by various switches installed on the operation unit 14. The recording medium in the unit 16 in which the recording medium is stored is conveyed into the plotter 10 based on an instruction from the operation unit 14, and a color image is printed and discharged from the recording medium discharge port 18 in the direction of arrow A. Is done.

It is a schematic diagram explaining waste ink discharged from a waste ink discharge pipe and an ink accumulation state in a conventional example. It is a perspective view which shows schematic structure of a plotter. 1 is a schematic diagram of an embodiment according to the present invention. It is a perspective view of the waste ink tank part of one embodiment by the present invention. It is a perspective view of the waste ink tank part of one embodiment by the present invention. It is a perspective view of the waste ink tank part of one embodiment by the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Plotter 12 Recording medium 14 Platen 16 Scan rail 18 Belt 20 Carriage 22 Recording head 23 Image formation area 24 Conveyance roller 26 Pinch roller 30 Recovery device 32 Cap stand 41 Waste ink discharge pipe 42 Exhaust pipe 43 Discharge pipe 44 Joining part 45 Suction Pump 46 One-way valve 47 Waste ink tank 48 Waste ink absorber 49 Discharge pipe holding member 51 Ink deposit

Claims (7)

Recovery means for recovering or maintaining the discharge state of ink from the recording head, waste ink holding means for holding waste ink discharged from the recovery means, and a discharge pipe for ejecting waste ink discharged from the recovery means And an ink-holding means for absorbing waste ink ejected from the discharge pipe. An ink jet recording apparatus comprising an air supply mechanism for ejecting waste ink discharged from the recovery means from a discharge pipe, wherein the waste ink discharged from the discharge pipe is mixed with an air flow of the air supply mechanism An ink jet recording apparatus having an area for diffusing waste ink around an outlet of the discharge pipe 3. The ink jet recording apparatus according to claim 2, wherein the air feeding mechanism uses a wind of a suction mechanism that adsorbs the recording medium to the platen. The inkjet recording apparatus according to claim 2, wherein the air supply mechanism uses a wind of a suction mechanism that sucks ink mist. 6. The ink jet recording apparatus according to claim 2, wherein the air supply mechanism includes an exhaust pipe through which airflows generated from the platen suction mechanism and the ink mist suction mechanism flow. 7. The ink jet recording apparatus according to claim 2, wherein the waste ink discharge pipe includes a one-way valve between the recovery means and the coupling portion.

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