JP2007152780A - Prevention of hardening of waste ink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording device which achieves the prevention of hardening of waste ink by leading the waste ink ejected from a recording head and flowing from an ink recovery section, to a downstream waste ink tank without hardening, to thereby eliminate blocking of a waste ink channel with the waste ink. <P>SOLUTION: In implementation of the prevention of hardening of the waste ink, an oscillation generating means such as an ultrasonic oscillator is arranged in the waste ink channel for leading the waste ink to the waste ink tank, and functions to apply oscillation to the waste ink, to thereby prevent the waste ink from hardening. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus, and more particularly to an ink jet recording apparatus having means for preventing waste ink sticking.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus uses ink or the like by adhering paper dust or dust near the discharge port of a recording unit (recording head), increasing the viscosity of ink in the discharge port, or mixing air into the ink in the recording unit. In some cases, ejection failure such as non-ejection or misalignment in the ejection direction may occur, causing image defects such as missing dots or misalignment.

  Therefore, as a method for preventing such ejection failure, preliminary ejection is performed before entering the recording operation. The preliminarily ejected ink is collected at a preparatory ejection port provided at a position facing the ejection port surface of the recording head (see the first conventional example, for example, Patent Document 1).

  In the case of borderless recording in which recording is performed on the recording member without surrounding margins, the ink from the recording head is ejected to the outside of the end surface of the recording member. Here, the ink ejected to the outside of the recording member is collected in a groove provided on the platen on the opposite side across the recording head and the recording member (second conventional example, for example, Patent Document 2). reference).

However, these ink collection units are portions that are temporarily collected because a large capacity cannot be obtained, and a waste ink tank is finally stored. The recovery unit communicates with the waste ink tank through a waste ink channel.
JP-A-11-198413 (7th page, FIG. 6) Japanese Patent Application Laid-Open No. 2002-068221 (page 9, FIG. 5)

  However, it is not always possible to dispose the waste ink tank directly below the waste ink collection unit. In this case, the waste ink flow path that communicates the two is not vertical, and approaches the horizontal as the distance between the two increases.

  The state until the pre-discharged ink is collected in the waste ink tank will be described with reference to FIG. 101 is a recording head, 102 is a recording member, the recording head 101 is movable in the direction of the arrow, and the recording member 102 is conveyed from the back side to the near side. Reference numeral 103 denotes a waste ink flow path, which has a preliminary discharge port 103a at the top, a preliminary discharge port 103b at the bottom, and a slope 103c at the center. Reference numeral 104 denotes a waste ink tank in which a waste ink absorber 105 is accommodated. A preliminary discharge / discharge port 103 b is provided on the upper portion of the waste ink absorber 105.

  The preliminary discharge port 103a is located on the opposite side of the recording head 101 with the recording member 102 interposed therebetween, and the recording head 101 moves onto the preliminary discharge port 103a and discharges ink toward the preliminary discharge port 103a when performing the preliminary discharge operation. Then, the ink discharged to the preliminary discharge port 103a flows along the inclined surface 103c of the waste ink flow path 103, falls from the preliminary discharge discharge port 103b onto the waste ink absorber 105, and is held.

  Here, since the reserved waste ink flows on the slope 103c due to gravity, when the slope 103c approaches the horizontal, the flow velocity becomes slow, and before reaching the waste ink tank 104, the inner wall of the waste ink flow path. There is a possibility that, for example, a fixed object K (shaded portion) is generated.

  When the waste ink starts to be fixed in this manner, the cross-sectional area of the waste ink flow path gradually becomes narrow, and eventually the waste ink flow path is completely blocked by the waste ink fixed to the inner wall. There was a possibility that waste ink would overflow from the collection unit.

  The present invention has been made in view of the above-described problems. A recording head that discharges ink from an ejection port to perform recording on a recording member; and a recording head that faces the ejection port surface of the recording head, In the ink jet recording apparatus, comprising: an opening that collects the ejected ink; a waste ink tank that stores waste ink; and a waste ink channel that communicates the opening and the waste ink tank. The road has vibration generating means. Further, the vibration generating means is based on ultrasonic waves.

  In the present invention, since the waste ink flow path is vibrated by the vibration generating means by the above means, the waste ink discharged from the recording head and flowing from the ink recovery unit flows to the waste ink tank on the downstream side without being fixed. As a result, the waste ink does not adhere and become blocked in the waste ink flow path. Further, since the waste ink does not adhere even if the inclination of the waste ink flow path from the ink recovery unit to the waste ink tank is loosened, the degree of freedom in disposing the waste ink tank increases. In addition, the waste ink collection unit for preliminary ejection and the borderless collection unit are usually separated from each other, but a waste ink channel that leads to one waste ink tank may be provided.

Example 1
FIG. 1 is a partial cross-sectional view of the vicinity of a suction recovery portion of an ink jet recording apparatus according to a first embodiment to which the present invention is applied.

  1 is a recording head, 2 is a recording member, the recording head 1 is movable in the direction of the arrow, and the recording member 2 is conveyed from the back side to the front side of the paper. 3 is a suction recovery portion of the recording head 1, 3 a is a cap that prevents the ink discharge portion of the recording head 1 from drying, and 3 b is a tube pump that forcibly sucks the ink in the recording head 1 by a negative pressure. Rotate to. 3c is a tube that allows the sucked ink to flow downstream. A waste ink tank 4 contains a waste ink absorber 5 therein. The waste ink absorber 5 is made of a material having good absorbability in order to absorb waste ink. A waste ink flow path 6 has a preliminary discharge port 6a at the top, a preliminary discharge port 6b at the bottom, and a slope 6c at the center. An ultrasonic vibrator 7 is provided on the outer wall of the waste ink flow path 6, and the element vibrates by applying a voltage. Above the waste ink absorber 5, a tube of the suction recovery unit 3 and a preliminary discharge outlet 6 b of the waste ink flow path 6 are provided so that the waste ink is received by the waste ink absorber 5. .

  Next, an operation for collecting waste ink will be described. Ink ejection defects are likely to occur due to dust and thick ink adhering to the ink ejection part during normal use, bubbles in the recording head 1 during normal use, and ink sticking near the ink ejection part during unpacking. Therefore, in order to eliminate these defects and maintain image quality, ink is sucked from the ink discharge portion as a method for recovery of discharge. Specifically, the recording head 1 is moved onto the suction recovery unit 3 and the ink discharge unit is covered with a cap 3a. When the tube pump 3b is rotated counterclockwise in this state, the tube 3 around the tube pump 3b is crushed, and the negative pressure generated by the volume change in the tube 3 acts on the ink discharge portion of the recording head 1, and the ink discharge portion. Ink is sucked out (sucked out). The sucked ink passes through the tube 3 and is sequentially sent onto the waste ink absorber 5.

  On the other hand, when preliminary ejection is performed for the purpose described in the background art, the recording head 1 is moved onto the preliminary ejection port 6a and ink is ejected toward the preliminary ejection port 6a. Then, the ink discharged to the preliminary discharge port 6a flows along the inclined surface 6c of the waste ink flow path 6 and falls onto the waste ink absorber 5 from the preliminary discharge port 6b. At this time, a voltage is simultaneously applied to the ultrasonic transducer 7. By doing in this way, vibration is transmitted to the waste ink flow path 6, and the waste ink flowing on the inclined surface 6c can be reliably flowed on the absorber 5 without being fixed.

(Example 2)
FIG. 2 is a sectional view of the ink jet recording apparatus according to the second embodiment. The difference from the first embodiment is that, in addition to the preliminary discharge port, a recovery port for borderless recording is provided. The same mechanical parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  A waste ink flow path 11 includes a preliminary discharge port 11a, a preliminary discharge port 11b, a discharge port 11c without a reference side edge, a discharge port 11d without a non-reference side edge, and a discharge port 11e without a border. An ultrasonic vibrator 12 is provided on the outer wall of the waste ink flow path 11, and the element vibrates by applying a voltage.

  The operation of collecting the waste ink is the same as in the first embodiment, and applying a voltage to the ultrasonic vibrator 12 vibrates the waste ink flow path 11 so that the waste ink flowing inside is fixed. It can prevent and flow on the absorber 5 reliably.

  In both the first and second embodiments, a voltage was applied to the ultrasonic vibrator provided outside the waste ink flow path in order to apply vibration to the waste ink flow path. For example, a method may be used in which the waste ink flow path is vibrated by rotating the eccentric member previously attached.

  Even if an ultrasonic transducer is used, the mounting position and number may be different from those in the embodiment.

1 is a partial cross-sectional view around a suction recovery portion of an ink jet recording apparatus according to a first embodiment to which the present invention is applied. FIG. 6 is a partial cross-sectional view of the vicinity of a suction recovery portion of an ink jet recording apparatus that is a second embodiment to which the present invention is applied. FIG. 7 is a partial cross-sectional view around a suction recovery portion of a conventional inkjet recording apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording head 2 Recording member 3 Suction recovery part 3a Cap 3b Tube pump 3c Tube 4 Waste ink tank 5 Waste ink absorber 6 Waste ink flow path 6a Pre-discharge port 6b Pre-discharge port 6c Slope 7 Ultrasonic transducer 11 Waste ink Flow path 11a Preliminary discharge port 11b Preliminary discharge port 11c Reference side edgeless discharge port 11d Non-reference side edgeless discharge port 11e Edgeless discharge port 12 Ultrasonic transducer

Claims (2)

  A recording head that records ink on a recording member by ejecting ink from an ejection port, an opening that collects ink ejected from the recording head opposite to the ejection port surface of the recording head, and waste ink are stored An ink jet recording apparatus having a waste ink tank and a waste ink flow path communicating with the opening and the waste ink tank, wherein the waste ink flow path has vibration generating means. .   2. The ink jet recording apparatus according to claim 1, wherein the vibration generating means is an ultrasonic wave.

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