JP2007038558A - Inkjet image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet image forming device with an ink absorbing body which is free from misregistration, deformation and degradation. <P>SOLUTION: A cleaning blade 56 is stopped at the time when the cleaning blade 56 passes a face side 20Ks and arrives at the receiving surface 24a of a receiving member 24. The cleaning blade 56 in the stationary condition strongly contacts the receiving surface 24a of the receiving member 24 and very weakly contact the lower end surface 22b of an ink absorbing member 22. Consequently, since a force attributed to the elastic force of the cleaning blade 56 acts on the receiving member 24 and is received, the force does not act on the ink absorbing member 22. As a result, the ink absorbing member 22 does not get displaced, deformed or degraded by the force from the cleaning blade 56. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet image forming apparatus provided with a cleaning blade for cleaning a face surface of a recording head (printing head), for example, an ink jet image forming apparatus having a plurality of long recording heads.

  2. Description of the Related Art Inkjet image forming apparatuses that form images by ejecting ink onto recording media such as recording paper are widely used. The image forming apparatus includes a recording head in which a plurality of nozzles for discharging ink and a plurality of ink discharge ports (nozzle outlets) are formed. The plurality of ink discharge ports are substantially flat ink discharge port formation surfaces ( Formed on the face). There are two types of recording heads: a type that ejects ink while moving in the main scanning direction together with the carriage (scanning type), and a type that ejects ink while being fixed and stopped (line head type).

  In the above-described inkjet type image forming apparatus, when ink is ejected from the recording head, fine floating ink particles (ink mist) are generated along with the main flying ink droplets. This ink mist may adhere to the face surface of the recording head and cause ink wetting, or dust such as paper dust generated from the recording medium (recording material) may adhere to the face surface. Also, the pressure recovery operation of pressurizing the ink in the nozzle and pushing the ink from the ink discharge port may cause ink to adhere to the face surface and cause ink wetting. Such ink wetting and dust on the face surface hinders normal ink ejection from the ink ejection port, and causes the occurrence of ink deflection that can change the direction of ink ejection and ink ejection failure at the ink ejection port. There is a risk of degradation of recording quality.

As a method for removing foreign matters such as ink adhering to the face surface of the recording head, a cleaning blade (blade member) provided in the recovery mechanism is rubbed against the face surface and cleaned (wiping operation). ing. As a result of this wiping and cleaning, foreign matters such as ink adhere to the blade member. In order to remove such ink from the blade member, an ink absorber is attached to the recording head, and the blade member is brought into contact with the ink absorber to absorb the ink (patent). Reference 1).
JP 2000-71466 A

  However, in the configuration in which the ink absorber 4 is attached to the recording head 2 as shown in FIG. 8, the blade member 6 contacts the ink absorber 4 after cleaning the face surface 2 s of the recording head 2. During this contact, the blade member 6 rubs the ink absorber 4, so that a force that can be peeled off from the recording head 2 acts on the ink absorber 4. Since the position of the ink absorber 4 is shifted or deteriorated by such an action, the contact between the ink absorber 4 and the blade member 6 becomes insufficient, and the ink adhering to the blade member 6 is absorbed by the ink. The body 4 may not be able to be absorbed reliably.

  If the ink adhering to the blade member 6 after cleaning the face surface 2s cannot be reliably absorbed by the ink absorber 4, the face surface 2s is cleaned again with the blade member 6 with the ink attached. As a result, the face surface 2s cannot be sufficiently cleaned. Therefore, there arises a problem that the face surface 2s cannot always be maintained in a clean (cleaned) state. Further, when the ink absorber 4 is deteriorated in degree of wrinkling or deterioration, ink droplets attached to the blade member 6 are scattered by the wiping operation, and the ink is attached to the image forming apparatus or the recording medium. The problem that it ends up also arises.

  SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides an ink jet type image forming apparatus provided with an ink absorber that is not displaced, deformed or deteriorated, and a recording head mounted on the ink jet type image forming apparatus. For the purpose.

In order to achieve the above object, an ink jet type image forming apparatus according to the present invention provides a predetermined cleaning direction for the face surface of a recording head having a face surface in which a plurality of ink discharge ports for discharging ink are arranged in a certain direction. In an inkjet image forming apparatus comprising: a cleaning blade that cleans while moving to a position; and an ink absorber that is disposed downstream of the face surface in the cleaning direction and absorbs ink adhering to the cleaning blade.
(1) A receiving member that receives a force from the cleaning blade when the cleaning blade contacts or approaches the ink absorber is provided.

here,
(2) The receiving member includes a plurality of convex portions that protrude in the cleaning direction from the side surface of the recording head downstream of the face direction in the cleaning direction and are arranged at predetermined intervals in the fixed direction. And
(3) The ink absorber may be located between the plurality of convex portions.

Also,
(4) The plurality of convex portions have their lower surfaces located on the same plane as the face surface,
(5) The ink absorber may be disposed at a position retracted from the face surface.

further,
(6) The same number of cleaning blades as the number of the recording heads may be provided.

Furthermore,
(7) The ink absorber may be detachably attached to the recording head.

Furthermore,
(8) The ink absorber may be fixed to a plate-shaped fixing member, and may be detachably attached to the recording head together with the fixing member.

Furthermore,
(9) The cleaning blade may stop for a predetermined time when contacting the ink absorber.

Furthermore,
(10) The predetermined time may be a time until the ink adhering to the cleaning blade is absorbed by the ink absorber.

Further, the recording head of the present invention for achieving the above object is a recording head having a face surface in which a plurality of ink discharge ports for discharging ink are formed side by side in a certain direction.
(11) A receiving member that receives a force from the cleaning blade when the cleaning blade contacts or approaches an ink absorber that absorbs ink adhering to the cleaning blade that cleans the face surface is provided. It is what.

here,
(12) The receiving member includes a plurality of convex portions protruding in the cleaning direction from a side surface of the recording head on the downstream side in the cleaning direction with respect to the face surface.
(13) The ink absorber may be located between the plurality of convex portions.

further,
(14) The plurality of convex portions have lower surfaces located on the same plane as the face surface,
(15) The ink absorber may be disposed at a position retracted from the face surface.

  According to the present invention, when the cleaning blade contacts or approaches the ink absorber, the receiving member receives the force from the cleaning blade and does not act on the ink absorber. Therefore, the position of the ink absorber is not shifted or the ink absorber is not deformed or deteriorated by the force from the cleaning blade. As a result, even if the ink absorber is used for a long period of time, the ink adhering to the cleaning blade is reliably absorbed. For this reason, the face surface is cleaned with a cleaning blade to which no ink is attached, so that the face surface is cleaned cleanly and deterioration in image quality due to contamination of the face surface is prevented.

  The present invention has been realized in a label printer that continuously prints on a plurality of labels.

  A label printer which is an example of the present invention will be described with reference to FIGS.

  FIG. 1 is a partial cross-sectional view schematically showing a label printer in a standby state. FIG. 2 is a partial cross-sectional view schematically showing the label printer during the transition to the printing operation. FIG. 3 is a partial cross-sectional view schematically showing a label printer that has undergone a printing operation. Here, an example in which the present invention is applied to a label printer will be described. However, the present invention is applicable to any type of inkjet recording apparatus regardless of the type of recording medium (recording material) used, such as plain paper or a card. It can be done.

  The label printer 10 is an ink jet full color line printer, and each color of black (20K), cyan (20C), magenta (20M), and yellow (20Y) in order from the upstream side in the paper passing direction (recording medium conveyance direction, arrow A direction). A head unit 20 in which a plurality of (four) recording heads (recording heads) for discharging the ink is arranged. Each of the recording heads 20K, 20C, 20M, and 20Y extends in a direction perpendicular to the paper surface of FIG. 1, and is longer than the maximum width of the recording medium to be conveyed.

  The label printer 10 also includes a transport unit 30 that transports the recording medium in the direction of arrow A. The transport unit 30 includes a pinch roller pair 32 that transports the roll paper P downstream in the direction of arrow A, and a paper discharge roller pair 34 that discharges the printed roll paper P. A roll unit 36 that supplies roll paper P is disposed upstream of the pinch roller pair 32 in the direction of arrow A. An image is formed by the head unit 20 while the roll paper P is conveyed from the roll unit 36 by the conveyance unit 30 in the direction of arrow A. The label printer 10 is also provided with a recovery mechanism 50 that recovers the ink ejection state from the recording heads 20K, 20C, 20M, and 20Y to the initial state. The recovery mechanism 50 includes a recovery rod 52 described later. In addition, below the label printer 10, ink tanks 21K, 21C, 21M, and 21Y that store ink supplied to the recording heads 20K, 20C, 20M, and 20Y are provided.

  A procedure for shifting from the standby state shown in FIG. 1 to the recording operation will be described. In the standby state of FIG. 1, the roll unit 36 feeds the roll paper P by a predetermined amount. Thereafter, a motor (not shown) is driven in the main body of the label printer 10 to raise the head unit 20 to a predetermined position as shown in FIG. 2, and a recovery rod motor (not shown). Accordingly, the recovery rod 52 moves downstream in the direction of arrow A and stops at the recovery rod retracted position. Thereafter, a motor (not shown) is driven, and as shown in FIG. 3, the head unit 20 in the raised position passes through the opening 52a of the recovery rod 52 and descends to the lower recording position.

  The roll paper P fed from the roll unit 36 is transported into the transport unit 30 by the pair of pinch rollers 32 of the transport unit 30, and the recording units 20K, 20C, 20M, and 20Y of the head unit 20 are transported by the transport unit 30. It is conveyed (paper fed) through the vicinity of the lower surface of the face surface (ink discharge port surface) 20Ks, 20Cs, 20Ms, and 20Ys. When the roll paper P passes through the vicinity of the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys of the recording heads 20K, 20C, 20M, and 20Y, the ink discharge ports 20Ka formed on the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys. , 20Ca, 20Ma, and 20Ya are ejected onto the roll paper P to form an image. The roll paper P on which the image is formed is discharged out of the apparatus main body by the discharge roller pair 34.

  When recording is completed on a predetermined number of labels, the head unit 20 is raised to a predetermined position by driving a motor (not shown), and a recovery rod 52 is moved by a recovery rod motor (not shown). It moves upstream in the direction of arrow A and stops at a predetermined position below the head unit 20. At this position, the face unit 20Ks, 20Cs, 20Ms, 20Ys of each recording head 20K, 20C, 20M, 20Y is fixed to the recovery rod 52 by driving the motor (not shown) and lowering the head unit 20. The face surfaces 20Ks, 20Cs, 20Ms, and 20Ys are sealed by being brought into pressure contact with a cap 54 (usually a rubber elastic cap). As a result, the ink discharge ports 20Ka, 20Ca, 20Ma, and 20Ya are also sealed with the cap 54. The reason why the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys are sealed with the cap 54 is to prevent ink drying and dust adhesion around the respective ink discharge ports 20Ka, 20Ca, 20Ma, and 20Ya. The procedure returns to the standby state shown in FIG.

  A cleaning blade 56 for cleaning the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys is attached to the recovery rod 52 of the label printer 10. The cleaning blade 56 will be described with reference to FIG.

  FIG. 4 is a partial cross-sectional view showing a cleaning blade for cleaning the face surface of one recording head. 4 shows the cleaning blade 56 that cleans the face surface 20Ks of the recording head 20K, the cleaning blade 56 that cleans the face surfaces 20Cs, 20Ms, and 20Ys of the other recording heads 20C, 20M, and 20Y has the same structure.

  A cleaning blade 56 for wiping off ink adhering to the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys of the recording heads 20K, 20C, 20M, and 20Y is disposed on the recovery rod 52 of the label printer 10. , 20M and 20Y. The cleaning blade 54 is brought into contact with the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys with an elastic force and is moved relative to the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys toward the upstream side in the arrow A direction. The face surfaces 20Ks, 20Cs, 20Ms, and 20Ys are wiped off and cleaned, and the deposits on the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys are removed (cleaned). The lower end portion of the cleaning blade 56 is fixed to a fixing member 58, and both end portions in the longitudinal direction of the fixing member 58 are biased upward (in the direction of arrow B) by springs 59 from below. In addition, an ink guide 60 that guides (guides) the ink pushed out to the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys downward is disposed in the space surrounded by the cap 54.

  The cleaning blade 56 is a plate-shaped member made of an elastic material (rubber elastic body). The length of the cleaning blade 56 (the length in the direction perpendicular to the paper surface of FIG. 4) is substantially the same as the length of the recording head 20K. The cleaning blade 56 wipes and cleans the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys based on a pre-recording or other predetermined sequence to maintain the recording quality. In this embodiment, the moving path of the tip 56a of the cleaning blade 56 is overlapped with the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys to bend the tip 56a and drive a recovery rod motor (not shown). A head recovery sequence in which the recovery rod 52 is moved toward the upstream side in the direction of arrow A (in the direction opposite to the direction of arrow A) and pressed against the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys by the elastic force of the cleaning blade 56 itself. Is adopted. That is, a wiping operation for wiping and cleaning foreign matters such as ink and dust adhering to the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys by rubbing the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys with the cleaning blade 56 is performed. Executed.

  At the time when the wiping operation is completed, foreign matters such as ink adhere to the surface of the cleaning blade 56 (the surface in contact with the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys). An ink absorbing member (ink absorber) 22 that removes the foreign matter from the cleaning blade 56 is detachably fixed to the recording heads 20K, 20C, 20M, and 20Y. The structure of the recording heads 20K, 20C, 20M, and 20Y to which the ink absorbing member 22 is fixed will be described with reference to FIGS.

  FIG. 5 is a perspective view showing a recording head on which an ink absorbing member is mounted. FIG. 6 is a perspective view showing the recording head from which the ink absorbing member has been removed. FIG. 7 is a schematic diagram illustrating a state where the cleaning blade is temporarily stopped. In these drawings, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the recording head 20K is shown, but the other recording heads 20C, 20M, and 20Y are the same. It is a structure. Therefore, the label printer 10 is provided with the same number of cleaning blades as the number of recording heads.

  An ink absorbing member 22 is detachably attached to the recording head 20K on the downstream side of the face surface 20Ks in the cleaning direction (direction of arrow C opposite to the direction of arrow A). The ink absorbing member 22 absorbs foreign matter such as ink adhering to the cleaning blade 56, and has approximately the same size as the side surface 20Kb of the recording head 20K. The recording head 20 </ b> K is formed with a receiving member 24 that receives a force from the cleaning blade 56 when the cleaning blade 56 contacts the ink absorbing member 22. The receiving members 24 protrude in the cleaning direction from the side surface 20Kb downstream of the recording head 20K in the cleaning direction (arrow C direction) with respect to the face surface 20Ks, and are arranged in the length direction of the recording head 20K at a predetermined interval. It is comprised from the convex part 24 (five in a figure). Each convex portion 24 is formed with a receiving surface 24a on the same plane as the face surface 20Ks. A gap 24b is formed between adjacent convex portions 24 (adjacent convex portions 24 are separated by a predetermined distance), and a lower end portion 22a of the ink absorbing member 22 is inserted into this gap. In other words, the lower end portion 22a of the ink absorbing member 22 has a comb shape, and the convex portion 24 is inserted between the comb teeth.

  The lower end surface 22 b of the ink absorbing member 22 is in a position retracted from the receiving surface 24 a of the receiving member 24. Alternatively, the lower end surface 22b may be the same surface as the receiving surface 24a (that is, the same surface as the face surface 20Ks). That is, the lower end surface 22b is disposed at a position that does not protrude below the receiving surface 24a. The reason why the lower end surface 22b does not protrude below the receiving surface 24a in this way is that the force from the cleaning blade 56 is not received by the ink absorbing member 22 (without acting on the ink absorbing member 22). ) For receiving by the receiving member 24.

  Between each convex part 24 and side 20Kb, the clearance gap 24c in which the fixing member 70 mentioned later is inserted is formed. The fixing member 70 is plate-shaped and is used to easily attach the ink absorbing member 22 to the recording head 22K in a detachable manner. The fixing member 70 has an area approximately the same as the side surface 20Kb, and the lower end portion 70a thereof is inserted into the gap 24c. In addition, two protrusions 70 b are formed on the upper end of the fixing portion 70. The two protrusions 70b are inserted into slits 20Kt formed in the recording head 20K.

  The plate-shaped ink absorbing member 22 is fixed to the surface of the fixing member 70 (the surface opposite to the surface facing the side surface 20Kb) with a double-sided adhesive tape or the like, and the lower end portion 70a of the fixing member 70 is inserted into the gap 24c. Two protrusions 70b are inserted into the slits 20Kt of the recording head 20K. Thereby, the ink absorbing member 22 is easily fixed to the recording head 20K. When the ink absorbing member 22 is removed from the recording head 20K, the lower end portion 70a of the fixing member 70 is extracted from the gap 24c, and the two protrusions 70b are extracted from the slit 20Kt of the recording head 20K.

  When cleaning the face surface 20Ks with the cleaning blade 56 described above, the recording head 20K is fixed, and a recovery rod motor (not shown) is driven so that the face surface 20Ks moves from upstream to downstream in the direction of arrow C. Then, the face 20Ks is wiped while moving the cleaning blade 56. Thereby, the ink or the like adhering to the face surface 20Ks moves to the cleaning blade 56, and the face surface 20Ks is cleaned. When the cleaning blade 56 passes through the face surface 20Ks and reaches the receiving surface 24a of the receiving member 24, the recovery rod motor (not shown) is stopped to stop the cleaning blade 56. In this stopped state, the cleaning blade 56 is in strong contact with the receiving surface 24 a of the receiving member 24, and is only in very weak contact with the lower end surface 22 b of the ink absorbing member 22. For this reason, since the force resulting from the elastic force of the cleaning blade 56 acts on the receiving member 24 and is received, this force does not act on the ink absorbing member 22. As a result, the position of the ink absorbing member 22 is not shifted or the ink absorbing member 22 is not deformed or deteriorated by the force from the cleaning blade 56. Therefore, even if the ink absorbing member 22 is used for a long period of time, the ink adhering to the cleaning blade 56 is reliably absorbed. For this reason, the face surface 20Ks is always cleaned by the cleaning blade 56 to which no ink is attached, so that the face surface 20Ks is cleaned cleanly, and deterioration in image quality due to contamination of the face surface 20Ks is prevented.

  The stop time in which the cleaning blade 56 is stopped in a state of being in strong contact with the receiving surface 24a of the receiving member 24 is absorbed until the ink adhering to the cleaning blade 56 is absorbed by the ink absorbing member 22 (absorbed). Time). After this stop time has elapsed, a motor (not shown) is driven to raise the head unit 20 to a predetermined position, and a recovery rod 50 (see FIG. 1 etc.) is restored by a recovery rod motor (not shown). ) Is moved in the direction of arrow A and stopped at a predetermined position below the head unit 20. Thereafter, the motor (not shown) is driven to lower the head unit 20, and the face surfaces 20Ks, 20Cs, 20Ms, and 20Ys of the recording heads 20K, 20C, 20M, and 20Y are covered with caps 54 as shown in FIG. Seal.

It is a partial cross section figure which shows typically the label printer of a standby state. It is a partial cross section figure which shows typically the label printer in transfer to printing operation. It is a partial cross section figure which shows typically the label printer which became printing operation. FIG. 4 is a partial cross-sectional view illustrating a cleaning blade that cleans the face surface of one recording head. FIG. 4 is a perspective view showing a recording head equipped with an ink absorbing member. FIG. 4 is a perspective view illustrating a recording head from which an ink absorbing member has been removed. It is a schematic diagram which shows the state which the cleaning blade has stopped temporarily. It is a schematic diagram showing a recording head provided with a conventional ink absorbing member.

Explanation of symbols

10 Label printer 20K, 20C, 20M, 20Y Recording head 20Ks, 20Cs, 20Ms, 20Ys Face surface 22 Ink absorbing member 24 Receiving member 56 Cleaning blade 70 Fixing member

Claims (11)

A cleaning blade for cleaning the recording head while moving the face surface of the recording head in a predetermined cleaning direction having a face surface in which a plurality of ink discharge ports for discharging ink are arranged in a certain direction, and the cleaning is performed more than the face surface. In an inkjet image forming apparatus provided with an ink absorber that absorbs ink adhering to the cleaning blade, disposed on the downstream side in the direction,
An ink jet type image forming apparatus comprising: a receiving member that receives a force from the cleaning blade when the cleaning blade contacts or approaches the ink absorber. The receiving member is composed of a plurality of convex portions that protrude in the cleaning direction from the side surface of the recording head downstream of the face surface with respect to the cleaning direction and are arranged at predetermined intervals in the fixed direction.
The inkjet image forming apparatus according to claim 1, wherein the ink absorber is located between the plurality of convex portions. The plurality of convex portions have their lower surfaces located on the same plane as the face surface,
The ink-jet image forming apparatus according to claim 2, wherein the ink absorber is disposed at a position retracted from the face surface. The inkjet image forming apparatus according to claim 1, wherein the number of the cleaning blades is the same as the number of the recording heads. The inkjet image forming apparatus according to claim 1, wherein the ink absorber is detachably attached to the recording head. 6. The inkjet according to claim 5, wherein the ink absorber is fixed to a plate-like fixing member and is detachably attached to the recording head together with the fixing member. Method image forming apparatus. The inkjet type image forming apparatus according to any one of claims 1 to 6, wherein the cleaning blade is stopped for a predetermined time when it comes into contact with the ink absorber. 8. The inkjet image forming apparatus according to claim 7, wherein the predetermined time is a time until the ink adhering to the cleaning blade is absorbed by the ink absorber. In a recording head having a face surface in which a plurality of ink discharge ports for discharging ink are formed side by side in a certain direction,
A recording apparatus comprising: a receiving member that receives a force from the cleaning blade when the cleaning blade contacts or approaches an ink absorber that absorbs ink adhering to the cleaning blade that cleans the face surface. head. The receiving member is composed of a plurality of convex portions protruding in the cleaning direction from the side surface of the recording head downstream of the cleaning direction with respect to the face surface,
The recording head according to claim 9, wherein the ink absorber is located between the plurality of convex portions. The plurality of convex portions have their lower surfaces located on the same plane as the face surface,
The recording head according to claim 10, wherein the ink absorber is disposed at a position retracted from the face surface.

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