JP2009137210A - Ink-jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording device capable of effectively performing maintenance operation by a simple method without damaging an ink discharge surface when performing the maintenance operation of a recording head. <P>SOLUTION: The ink-jet recording device comprises the recording head 7 having the ink discharge surface 10, and a maintenance device 20 performing the maintenance of the recording head 7. The maintenance device 20 comprises a suction cap unit 21 performing the suction operation of filling ink in a nozzle 8, and an ink absorbing unit 22 provided downstream of the suction cap unit 21 in the moving direction of the recording head 7 after the suction operation, and having an ink absorber 27 contacting ink stuck to the ink discharge surface 10 in a non-contact state with the ink discharge surface 10 to absorb the ink. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus, and more particularly to an ink jet recording apparatus including a maintenance device that performs a maintenance operation of a recording head.

  2. Description of the Related Art Conventionally, many image recording apparatuses using an ink jet method have been used as image recording means capable of recording an image simply and inexpensively. An image recording apparatus using an inkjet method (hereinafter referred to as “inkjet recording apparatus”) uses, for example, a piezoelectric element such as a piezo element, a heater, or the like, to discharge ink from a liquid discharge port of a nozzle of a recording head. The ink is ejected as droplets onto a recording medium such as paper, and image recording is performed while ink is permeated or fixed on the recording medium.

  However, in such an ink jet recording apparatus, when the recording operation is continuously performed, the mist-like ink ejected from the nozzles of the recording head adheres to and accumulates in the vicinity of the ink ejection openings of the nozzles or the ink ejection surface. Or clogging may occur in the nozzle. In particular, when an active energy ray-curable ink that is cured by irradiation with active energy rays is used, the ink attached to the ink ejection surface or the like may be cured by reflected light or the like, and recording is performed in such a state. When the operation is performed, even if the ejection operation is performed by driving an actuator such as a piezo element, there is a discharge failure such as a so-called nozzle lack in which ink droplets are not discharged or a so-called discharge bending in which ink droplets are not discharged in the correct direction. This may cause problems in image recording.

  Further, in order to normally eject ink from the ink ejection port of the nozzle, it is necessary that a meniscus having a normal shape is formed at the nozzle tip portion. When ink adheres to the vicinity of the ink discharge port and is cured by light irradiation, the shape of the meniscus is destroyed and normal ink discharge cannot be performed, and high-definition image recording cannot be performed.

Therefore, in order to perform normal image recording, it is necessary to appropriately perform a maintenance operation of the recording head.
As described above, when the nozzle is clogged and a so-called nozzle is missing, the ejection performance cannot be recovered by simply wiping off the ink on the ink ejection surface. In the operation, the ink discharge surface is covered with a suction cap, and an operation of once discharging ink from all the nozzles is performed by a method of applying a negative pressure by a suction pump.

  However, when the ink is ejected from the nozzle in this way, the ink adheres to the ink ejection surface, and this ink drops and adheres to each part of the apparatus, thereby contaminating each part of the apparatus or in particular oxetane compound. In the case of an active energy ray curable ink such as a cation curable ink contained therein, the adhesion of the ink causes inconveniences such as dissolution and corrosion of various parts.

  Therefore, after the operation of ejecting ink, for example, a technique for performing a maintenance operation for removing ink attached to the ink ejection surface by a brush-like ink removing unit (see, for example, Patent Document 1), or suction after the ink suction operation A technique for reducing the amount of ink adhering to the recording head by releasing the suction cap after removing the ink inside the suction cap by opening the atmosphere communication valve provided inside the cap (for example, Patent Document 2) has been proposed. In addition, even if the ink inside the suction cap is removed in this way, the ink adhering to the ink ejection surface cannot be completely removed. Therefore, in the technique described in Patent Document 2, the wiping means after the suction operation is performed. Wipe operation is performed.

Since a considerable amount of ink adheres to the ink ejection surface after the ink ejection operation, it is necessary to repeat the wiping operation many times in order to reliably remove the ink. However, the method of wiping the ink by repeatedly sliding the brush-like ink removing means and the wiping means on the ink discharge surface may damage the ink discharge surface, and particularly prevents the ink from adhering to the ink discharge surface. When a water repellent treatment is performed such as forming a water repellent layer, there is a problem that the water repellent layer is worn.
Accordingly, a technique has been proposed in which a cleaning roller for cleaning the ink discharge surface is provided, and a fine gap is secured between the ink discharge surface and the cleaning roller by a positioning member, and then the ink attached to the ink discharge surface is removed ( For example, see Patent Document 3).
JP 2003-311985 A Japanese Patent No. 3216706 JP 2007-175906 A

  However, it is difficult to sufficiently remove the ink adhering to the ink ejection surface only by cleaning with the cleaning roller, and it is difficult to remove ink particularly in the case of high viscosity ink such as active energy ray curable ink. There is a problem.

  Therefore, the present invention has been made to solve the above problems, and when performing a maintenance operation of the recording head, the maintenance operation can be effectively performed with a simple method without damaging the ink discharge surface. An object of the present invention is to provide an ink jet recording apparatus that can be used.

In order to solve such a problem, the invention described in claim 1
A recording head having a nozzle for ejecting ink and an ink ejection surface provided with an ink ejection port of the nozzle;
A maintenance device for maintaining the recording head,
The maintenance device includes a first maintenance unit that performs a first maintenance operation for filling the nozzles with ink, and a downstream side of the first maintenance unit in the moving direction of the recording head after the first maintenance operation. And an ink absorbing unit provided with an ink absorber that contacts and absorbs ink adhering to the ink discharge surface in a non-contact state with the ink discharge surface. Device.

  According to a second aspect of the present invention, in the ink jet recording apparatus according to the first aspect, the ink absorbing unit is configured so that the recording head is in contact with the recording head after the first maintenance operation with respect to the recording head. The ink absorbing operation is performed without stopping the movement of the ink.

  The invention described in claim 3 is the ink jet recording apparatus according to claim 1 or 2, wherein the first maintenance unit is one of an ink suction operation, a purge operation, and a flushing operation, or It is characterized in that a maintenance operation is performed by combining two or more of these.

  According to a fourth aspect of the present invention, in the ink jet recording apparatus according to any one of the first to third aspects, the ink absorption unit is connected to a waste liquid storage unit that receives the absorbed ink. It is characterized by that.

  According to a fifth aspect of the present invention, in the ink jet recording apparatus according to any one of the first to fourth aspects, the absorber that absorbs the ink is made of felt or olefin or polyolefin. It is characterized by being formed of any one of a nonwoven fabric made of resin and a high-density fiber.

  The invention described in claim 6 is the ink jet recording apparatus according to any one of claims 1 to 5, wherein the ink has a viscosity at 25 ° C. of 10 to 50 [mPa · s]. The surface tension is 20 to 40 [mN / m].

  The invention described in claim 7 is the ink jet recording apparatus according to any one of claims 1 to 6, wherein the ink contains an activation energy ray-curable compound, and the activation energy. Is characterized by ultraviolet rays.

  According to the present invention, as the maintenance operation, first, a first maintenance operation for filling the ink into the nozzle is performed. For this reason, for example, even when there is a nozzle that is not so-called nozzle missing, that is, there is a nozzle that cannot eject ink because the ink does not flow into an actuator such as a piezo element laid in the nozzle, After the maintenance operation, all nozzles can be filled with ink, and the ejection performance can be recovered.

  After such a maintenance operation, before the recording head shifts to the next operation, the ink absorption operation is performed by the ink absorber, so even if a large amount of ink is attached to the ink ejection surface By preventing the droplets from dropping and adhering to each part of the apparatus, it is possible to avoid the occurrence of contamination inside the apparatus, dissolution of various parts due to adhesion of ink droplets, corrosion, and the like.

  Further, since the ink absorption operation by the ink absorption unit is performed without contacting the ink discharge surface, the ink discharge surface is not damaged during the ink absorption operation.

  In addition, the ink absorption operation is performed before the next operation such as the wiping operation, and the ink droplets adhering to the ink ejection surface are absorbed. The removal of the ink adhering to the surface can be completed, the influence on the ink ejection surface can be minimized, and an efficient and effective maintenance operation can be performed.

  Hereinafter, a first embodiment of an ink jet recording apparatus according to the present invention will be described with reference to FIGS. 1 to 7.

  First, as shown in FIG. 1, in the present embodiment, an inkjet recording apparatus 100 is a serial head type inkjet recording apparatus, and includes an apparatus main body 1 and a support base 2 that supports the apparatus main body 1 from below. I have. A platen 3 that supports the recording medium S from the non-recording surface side is disposed in the apparatus main body 1 so as to extend in the longitudinal direction of the apparatus main body 1. The area where the platen 3 is provided is a recording area where image recording is performed, and the recording medium S is transported on the platen 3 in the sub-scanning direction Y, which is a predetermined transport direction, by a transport mechanism (not shown). ing.

  A bar-shaped guide rail 5 extending in the longitudinal direction of the apparatus main body 1 is provided above the platen 3 and upstream of the recording medium S in the sub-scanning direction Y. A carriage 6 is supported on the guide rail 5, and the carriage 6 reciprocates along the guide rail 5 in the main scanning direction X orthogonal to the sub-scanning direction Y by a moving mechanism (not shown).

  In the carriage 6, ink of each color (for example, yellow (Y), magenta (M), cyan (C), and black (K)) used in the ink jet recording apparatus 100 according to the present embodiment is applied to the recording medium S. Four recording heads 7 for discharging are mounted.

Inside the recording head 7, a plurality of nozzles 8 (see FIG. 3) for ejecting ink are provided in a row along the sub-scanning direction Y, and the surface of the recording head 7 facing the recording medium S is An ink discharge surface 10 (see FIG. 3 and the like) on which the ink discharge ports 9 of these nozzles 8 are formed. The ink discharge surface 10 is preferably subjected to a water repellent treatment such as a fluorine processing treatment such as FEP (fluorinated ethylene propylene resin) so that the ink hardly adheres.
In this embodiment, the case where one row of nozzles 8 is provided is taken as an example, but the arrangement of the nozzles 8 is not limited to this, and the nozzles 8 are arranged in parallel in the sub-scanning direction Y. May be provided.

  For example, a piezo element (not shown) as a piezoelectric element that is deformed by applying a voltage as an actuator is laid on the nozzle 8 of each recording head 7. By applying a driving voltage to the piezo element, the piezo element is deformed, an ink flow path (not shown) is compressed, and ink is ejected from the ink ejection port 9 of the nozzle 8. Ink is drawn into the inside of the nozzle 8 at the tip of the nozzle 8 to form a curved surface shape (meniscus). When the shape of the meniscus is properly adjusted, normal ink discharge can be performed.

Here, the ink used in this embodiment will be described.
When the ink is cured, the polymerizable compound contained in the ink is subjected to a polymerization reaction. The ink used for image recording in the present embodiment is an ultraviolet curable ink containing an activated energy ray-curable compound as a polymerizable compound and having an activation energy for starting a polymerization reaction of ultraviolet rays.

  The ultraviolet curable ink is roughly classified into a radical curable ink containing a radical polymerizable compound and a cation curable ink containing a cationic polymerizable compound as a polymerizable compound. Either ink can be used as the ink used in the present embodiment, and a hybrid ink in which a radical curable ink and a cationic curable ink are combined may be used as the ink used in the present embodiment.

  However, since the cationic curable ink that has little or no inhibition of the polymerization reaction by oxygen is superior in functionality and versatility, in this embodiment, the cationic curable ink is used in particular. The cation curable ink used in the present embodiment is specifically a mixture containing at least a cation polymerizable compound such as an oxetane compound, an epoxy compound, and a vinyl ether compound, a photo cation initiator, and a coloring material. It has the property of being cured by irradiation with ultraviolet rays.

  The ink in the present embodiment is a liquid having a viscosity at 25 ° C. of 10 to 50 [mPa · s] and a surface tension of 20 to 40 [mN / m], so-called high viscosity and wettability. The ink is not good.

  In order to enable high-definition image recording, it is desirable to reduce the viscosity of the ink so that one dot is ejected as a fine droplet of 2 to 20 pl. (Not shown) is preferably provided so that the ink is heated to lower the viscosity before the ink is ejected.

  On both sides of the recording head 7 of the carriage 6 in the main scanning direction X, there is a light source (not shown) that irradiates the ink discharged from the ink discharge port 9 of the nozzle 8 onto the recording medium S to cure the ink. The ultraviolet irradiation device 11 provided is provided.

  As the light source, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, a hot cathode tube, a cold cathode tube, a light-emitting diode, a semiconductor laser, and the like can be applied. It is not limited to what was illustrated.

A maintenance device 20 that performs a maintenance operation of the nozzles 8 and the ink ejection surface 10 of the recording head 7 is provided at one end outside the recording area, which is a movable range of the carriage 6.
As shown in FIGS. 2 and 3, in the present embodiment, the maintenance device 20 includes a suction cap unit 21, an ink absorption unit 22, and a wipe unit 23.

  The suction cap unit 21 is a first maintenance unit that performs a first maintenance operation for filling ink into the nozzles 8 by sucking ink from the nozzles 8 of the recording head 7.

The suction cap unit 21 includes a unit support 24. The unit support 24 is provided with four suction caps 25 that cover the ink ejection surface 10 of the recording head 7 corresponding to the recording head 7. The four suction caps 25 are configured to face the recording head 7 when the carriage 6 moves to the maintenance device 20.
The suction cap 25 is separated from the ink ejection surface 10 of the recording head 7 from a position where the ink ejection surface 10 of the recording head 7 can be covered when the recording head 7 moves to the maintenance device 20 by a drive mechanism (not shown). It can move to the position in the vertical direction in FIG. During the non-maintenance operation, the suction cap 25 is lowered to a predetermined standby position that is separated from the ink ejection surface 10 (for example, a position having a height α in FIG. 3).

  The suction cap unit 21 is connected to a waste liquid tank 33 that receives the sucked ink via the communication pipe 26. A suction pump (not shown) is provided in the middle of the communication pipe 26. When the suction cap 25 covers the ink discharge surface 10, ink in the nozzle 8 of the recording head 7 can be sucked and sent to the waste liquid tank. It is configured. As the suction pump, for example, a tube pump or the like can be used. However, it is sufficient if a suction force sufficient to suck the ink in the nozzle 8 can be secured, and other mechanisms are applied. Is also possible.

After the maintenance operation by the suction cap unit 21, the ink absorption unit 22 moves to the next operation (wiping operation described later in this embodiment) in the moving direction A of the recording head 7 (see FIG. 3, in this embodiment, It is provided on the downstream side of the suction cap unit 21 in the direction of movement from right to left along the main scanning direction X in FIG.
When ink is sucked by the suction cap unit 21, ink is filled into the nozzle 8 and ink is sucked out from the ink discharge port 9, and a part of the ink adheres to the ink discharge surface 10. The ink absorption unit 22 absorbs the ink adhering to the ink discharge surface 10 without contacting the ink discharge surface 10.

FIG. 4 is a perspective view showing a main configuration of the ink absorption unit 22.
As shown in FIGS. 3 and 4, the ink absorption unit 22 includes an ink absorber 27 and an absorber holder 28 that holds and stores the ink absorber 27.

As shown in FIG. 3, in the ink absorption unit 22, the upper end portion of the ink absorber 27 is the uppermost portion of the suction cap unit 21 and the wipe unit 23 (portion close to the ink discharge surface 10), and the maintenance operation is not performed. It is arranged so as to be located at a position higher than the height at which it is sometimes located (position close to the ink ejection surface 10).
That is, in the present embodiment, when the uppermost portions of the suction cap unit 21 and the wipe unit 23 are located at a height α during non-maintenance operation, and the position of the upper end portion of the ink absorber 27 is β. The position β of the upper end portion of the ink absorber 27 is higher than α.

As shown in FIG. 3, the ink absorbing unit 22 has a small gap (gap γ in FIG. 3) between the upper end portion of the ink absorber 27 and the ink ejection surface 10 during the ink absorbing operation. It is arranged at the position to be formed. The size of the gap γ is not particularly limited, but is preferably about the same as the distance between the recording medium S and the ink ejection surface 10 when performing the recording operation, for example, about 1.5 mm to 2 mm. preferable.
By arranging the ink absorption unit 22 at such a position, the ink absorber 27 does not contact the ink discharge surface 10 during the ink absorption operation, and adheres to the ink discharge surface 10 and bulges downward. In contact with the ink droplet, it can be absorbed (see FIG. 7).

  Here, a specific configuration of the ink absorption unit 22 will be described with reference to FIGS. 2 and 4.

The ink absorber 27 is formed in a substantially rectangular parallelepiped shape, and the length dimension in the longitudinal direction is the same as or longer than the length dimension in the longitudinal direction of the ink discharge surface 10 of the recording head 7. Moreover, although the width dimension is not specifically limited, For example, it is about 5 mm.
The material that forms the ink absorber 27 is a material that has excellent ink absorptivity, and is preferably a material that does not dissolve even if the ultraviolet curable ink or the like used in this embodiment adheres. Specifically, for example, it is formed of any material of felt, a nonwoven fabric made of olefin-based or polyolefin-based resin (for example, polyethylene (PE), polypropylene (PP), etc.), or high-density fiber. It is preferable. By forming the ink absorber 27 with such a material, ultraviolet curable ink, and other inks such as oil-based and solvent-based inks that have higher viscosity and less wettability than commonly used inks, Without contacting the ink ejection surface 10, the ink can be reliably absorbed simply by contacting the ink droplet.
The ink absorber 27 is only required to be formed of a material excellent in ink absorbability, and the material is not limited to those exemplified here.

The absorber holder 28 is made of a material that does not dissolve even when it comes into contact with ink (for example, a resin such as polyethylene (PE) or polypropylene (PP)). As shown in FIG. A storage portion 29 for storing the body 27 is provided. The bottom portion 30 of the storage portion 29 is inclined from one end side to the other end side in the longitudinal direction, and the absorber holding portion 28 is provided at one end of the bottom portion 30 on the lowest side (downstream side of the inclination). A through hole 31 penetrating outside is formed.
One end of an ink discharge pipe 32 is connected to the through hole 31, and the other end of the ink discharge pipe 32 is connected to a waste liquid tank 33 that is a waste liquid storage means. In this embodiment, the case where the waste liquid storage unit connected to the ink discharge pipe 32 and the waste liquid tank 33 connected to the suction cap unit 21 are the same (also used) is taken as an example. The means may be provided separately from the waste liquid tank 33 connected to the suction cap unit 21. Further, the waste liquid storage means connected to the absorber holding unit 28 does not have to be in a tank shape, and may be, for example, a tray shape that receives discharged ink.

  Support portions 35 a and 35 b for supporting the ink absorber 27 are formed at both longitudinal ends of the bottom portion 30 of the storage portion 29. Of the support portions 35a and 35b, the support portion 35b located on the downstream side of the slope of the bottom portion 30 (the lowest side of the bottom portion 30) is the upstream side of the slope of the bottom portion 30 (the highest of the bottom portion 30). The upper end portion of the support portion 35a is substantially equal to the upper end portion of the support portion 35b. Accordingly, the ink absorber 27 can be supported substantially horizontally by the support portions 35a and 35b.

The wipe unit 23 wipes the ink discharge surface 10 after the ink droplets are absorbed by the ink absorption unit 22.
The wipe unit 23 in the present embodiment will be specifically described with reference to FIGS. FIG. 5 is a side view showing a part of the wipe unit 23.

  As shown in FIG. 2, in the present embodiment, the wipe unit 23 has a box-shaped housing 37, and an opening 38 is formed on the top surface of the housing 37.

  Inside the housing 37 and at both ends in the sub-scanning direction Y, a feed shaft (not shown) for feeding the ink absorbing member 39 and a take-up shaft (not shown) for winding the ink absorbing member 39 are arranged. Has been. The wipe unit 23 is provided with a drive mechanism storage unit 40 in the vicinity of the housing 37. The drive mechanism storage unit 40 is not shown in the drawing, such as a motor that is connected to the winding shaft and rotationally drives the winding shaft. A drive mechanism is housed.

  A long sheet-shaped ink absorbing member 39 is wound around the feed shaft in a roll shape. The ink absorbing member 39 is stretched between the feed shaft and the take-up shaft while maintaining a constant tension by a plurality of guide rollers 41 (see FIG. 5), and a part thereof is exposed from the opening 38. It has become. As shown in FIG. 5, the ink absorbing member 39 exposed from the opening 38 faces the ink ejection surface 10 of the recording head 7 during the maintenance operation. The ink absorbing member 39 is fed from the feed shaft as the take-up shaft rotates, and is guided by the plurality of guide rollers 41 to be taken up by the take-up shaft.

The ink absorbing member 39 is formed from high-density fibers that are ultrafine fibers having a fineness of, for example, about 0.1 to 0.5 denier, and the high-density fibers are any one of polyester, acrylic, nylon, and the like. Or it is comprised by the material which combined these. As described above, since the ink absorbing member 39 is made of high-density fibers, the ink absorbing member 39 easily adsorbs the material that contacts the surface, and absorbs ink adhering to the ink ejection surface 10 of the recording head 7 regardless of the viscosity or wettability of the ink. In addition to the removal, the ink can be quickly absorbed from the tip of the nozzle 8 of the recording head 7. In other words, the ink absorbing member 39 in the present embodiment is reliable even if it is an ultraviolet curable ink or other ink that is higher in viscosity and less in wettability than a commonly used ink such as an oil-based or solvent-based ink. Can be absorbed into.
The ink absorbing member 39 only needs to be a high density fiber excellent in ink absorbability, and the material thereof is not limited to those exemplified here.

The size of the ink absorbing member 39 is not particularly limited. However, in order to perform a maintenance operation such as wiping the ink discharge surface 10 uniformly, at least the entire ink discharge surface 10 that is a target of the maintenance operation can be covered. It is preferable. In the present embodiment, the width is sufficient to cover the ink ejection surfaces 10 of the two recording heads 7 so that the maintenance operation of the two recording heads 7 can be performed at a time.
The maintenance operation of the recording head 7 by the wipe unit 23 may be performed for each recording head 7 one by one. In that case, the size of the ink absorbing member 39 only needs to be larger than the width of one ink ejection surface 10.

  Inside the housing 37, a pressing member 43 that presses the ink absorbing member 39 against the recording head 7 during a maintenance operation, and a guide member 44 (see FIG. 5) that guides the pressing member 43 are provided. .

  As shown in FIG. 5, the guide member 44 extends in the horizontal direction so that the central portion corresponding to the recording head 7 is substantially parallel to the ink ejection surface 10 of the recording head 7, and both ends are at the bottom. A guide hole 45 having a bent shape is formed. Both ends of the guide hole 45 are standby areas D.

The pressing member 43 includes a roller member 46 that presses the ink absorbing member 39 against the recording head 7, and a roller that supports the roller member 46 and has a locking portion 47 that is locked to the guide hole 45 of the guide member 44. And a support member 48.
The locking portion 47 is slidably locked with respect to the guide hole 45, whereby the roller support member 48 is guided along the guide hole 45.

  The material for forming the roller member 46 is not particularly limited. However, an elastic material such as a resin is preferable. In particular, as in the present embodiment, an ink containing an organic solvent such as an ultraviolet curable ink is used as the ink. For example, a material such as perfluoroelastomer that does not swell or dissolve even when ink is attached is preferable. It is also possible to use EPDM (Ethylene Propylene Diene Methylene Linkage).

  When the roller support member 48 is guided along the guide hole 45, the pressing member 43 moves up and down appropriately according to the shape of the guide hole 45, and the roller member 46 pushes the ink absorbing member 39 against the ink discharge surface 10. It is possible to move from a position where it can be applied to a standby position where it does not contact the tip of the recording head 7 (position of height α in FIG. 3). When the wipe unit 23 is not operated, or when the wipe unit 23 is operated and the carriage 6 is moved, the pressing member 43 is moved to the standby area D of the guide hole 45. By doing so, the ink discharge surface 10 of the recording head 7 does not come into contact with the roller member 46 when the carriage 6 moves.

  In addition, as shown in FIG. 1, an ink tank 49 that supplies ink of each color to the recording head 7 via an ink supply path (not shown) is provided at the other outer end of the recording area, which is the movable range of the carriage 6. Is provided. A liquid feed pump (not shown) for feeding ink from the ink tank 49 to the recording head 7 is provided in the middle of the ink supply path. As a result, even a highly viscous ink with poor wettability as used in this embodiment can be reliably fed from the ink tank 49 to the recording head 7.

  The ink jet recording apparatus 100 includes a control unit (not shown) that controls each part of the apparatus and a power supply unit (not shown) that is connected to the control unit and supplies power to each part of the apparatus.

As the recording medium S used in the present embodiment, various papers such as plain paper, recycled paper, and glossy paper, various fabrics, various non-woven fabrics, resin, metal, glass, and the like that are applied to a normal ink jet recording apparatus. Can be applied. Further, as the form of the recording medium S, a roll shape, a cut sheet shape, a plate shape, or the like is applicable.
Furthermore, as the recording medium S used in the present embodiment, known recording media such as various papers whose surfaces are coated with a resin, a film containing a pigment, and a foamed film are also applicable.

  Next, the effect | action of this embodiment is demonstrated, referring FIG.6 and FIG.7.

  When the power source of the ink jet recording apparatus 100 is turned on, power is supplied from the power source to each part of the ink jet recording apparatus 100. Then, when predetermined image information is sent to the ink jet recording apparatus 100 and the recording medium S is conveyed to a predetermined position in the recording area, the carriage 6 reciprocates along the guide rail 5 directly above the recording medium S.

  During the movement of the carriage 6, ink is ejected from the ink ejection ports 9 of the nozzles 8 of the recording head 7 toward the recording medium S based on image information sent from an external device (not shown) or an input unit. At the same time, the ultraviolet light is irradiated to the ink landed on the recording medium S from the ultraviolet irradiation device 11. At this time, the ink ejected from each recording head 7 is quickly cured by the ultraviolet rays irradiated from the ultraviolet irradiation device 11 located downstream of the recording head 7 in the moving direction of the carriage 6, so that the ink is deposited on the recording medium S. To settle.

  Thereafter, the ink jet recording apparatus 100 repeats the above operations, whereby an image is recorded on the recording medium S.

  When the predetermined number of times of image recording is performed, the maintenance operation of the recording head 7 by the maintenance device 20 is performed at an arbitrary time set by the user. The timing for shifting to the maintenance operation is not particularly limited. For example, the maintenance operation may be performed when a predetermined time has elapsed from the start of image recording or every time a predetermined number of images are recorded. Further, when the recording operation is not performed for a long time, the maintenance operation may be performed before the recording operation is started.

  As shown in FIG. 6, during the maintenance operation, first, the carriage 6 moves above the suction cap unit 21 of the maintenance device 20. When the carriage 6 moves above the suction cap unit 21, the suction cap 25 of the suction cap unit 21 rises upward (in the direction of arrow B in FIG. 6), and each suction cap 25 moves to the ink ejection surface 10 of each recording head 7. Close contact with. Then, the space between the ink discharge surface 10 and the suction cap 25 is decompressed by the suction pump to suck and remove foreign matters such as ink remaining in the nozzle 8 and newly fill the nozzle 8 with ink. Let This suction operation may be performed only once or may be repeated a plurality of times.

  When the suction operation is completed, the suction cap 25 of the suction cap unit 21 is lowered downward (in the direction of arrow C in FIG. 7A), and each suction cap 25 is separated from the ink ejection surface 10 of each recording head 7. At this time, as shown in FIGS. 7A and 7B, the ink droplets sucked out by the suction operation are attached to the ink discharge surface 10.

  Thereafter, the carriage 6 moves in the moving direction A in FIGS. 6 and 7 in order to shift to the wipe operation by the wipe unit 23 which is the next operation. At this time, the recording head 7 on the carriage 6 passes over the ink absorption unit 22 provided on the downstream side of the suction cap unit 21 in the moving direction A of the recording head 7. The ink droplets adhering to the ink contact with the upper end portion of the ink absorber 27, and the ink droplets are absorbed by the ink absorber 27 (see FIG. 7B). The absorbed ink flows along the inclination of the bottom portion 30 of the storage portion 29, flows into the waste liquid tank 33 from the through hole 31 through the ink discharge pipe 32, and is stored.

  As shown in FIG. 7B, when an ink absorbing operation is performed by the ink absorbing unit 22 for a certain recording head 7, the other recording head 7 is positioned above the suction cap 25 of the suction cap unit 21. As a result, even if ink is dripped from another recording head 7 during the ink absorption operation of a certain recording head 7, this can be received by the suction cap 25, and can be received by each part of the apparatus. Ink droplets can be prevented from adhering.

  Further, the recording head 7 on the carriage 6 sequentially moves above the wipe unit 23 while passing over the ink absorbing unit 22. At this time, the pressing member 43 is positioned in the standby area D so that the roller member 46 does not come into contact with the moving carriage 6 or the like. When two recording heads 7 located on the downstream side in the moving direction A among the recording heads 7 on the carriage 6 move to a predetermined maintenance position, the roller support member 48 is guided by the guide hole 45 and moved in the sub-scanning direction Y. To do. As a result, the roller member 46 fixed to the roller support member 48 moves along the guide hole 45 from the standby region D.

  At a position where the ink discharge surface 10 of the recording head 7 and the roller member 46 of the pressing member 43 face each other, the roller member 46 comes into contact with the ink absorbing member 39 from the side opposite to the side in contact with the ink discharge surface 10, and the ink The absorbing member 39 is pressed by the roller member 46 and comes into contact with the ink discharge surface 10. As a result, the ink absorbing member 39 comes into close contact with one end portion of the ink ejection surface 10. The pressing member 43 is guided by the guide hole 45 and reciprocates along the sub-scanning direction Y, so that the ink is wiped on the entire surface of the ink ejection surface 10 of the recording head 7 and the nozzles 8 are sequentially disposed. Ink is absorbed by the ink absorbing member 39 from the tip.

  When the maintenance operation for the two recording heads 7 is completed, the pressing member 43 stands by in the standby area D, and the carriage 6 further moves in the movement direction A in this state. During this time, the ink absorbing member 39 is wound around the take-up shaft, whereby the ink unabsorbed portion of the ink absorbing member 39 is exposed from the opening 38.

  Subsequently, the carriage 6 is moved by the width of the two recording heads 7 in accordance with the position of the ink absorbing member 39, and the wiping unit is similarly applied to the two recording heads 7 located upstream in the moving direction A. 23, the maintenance operation is performed. In this way, the operation of sequentially performing the movement of the pressing member 43, the movement of the ink absorbing member 39, and the movement of the carriage 6 for each of the two recording heads 7 is repeated, so that all the recording heads 7 are maintained by the wipe unit 23. The operation is complete.

  When the maintenance operation is completed for all the recording heads 7, the pressing member 43 stands by in the standby area D and the ink absorbing member 39 is wound up by the winding shaft, whereby the ink non-absorbing portion of the ink absorbing member 39 is opened. The part 38 is exposed.

  Thus, when a series of maintenance operations by the maintenance device 20 is completed, the carriage 6 returns to the recording area again, and the recording operation is resumed.

  As described above, in the inkjet recording apparatus 100 according to the present embodiment, as a maintenance operation, first, the suction operation by the suction cap unit 21 is performed to fill the nozzle 8 with ink. For this reason, for example, the nozzle 8 that cannot discharge ink because the ink does not flow into the so-called nozzle 8, that is, the actuator such as a piezo element laid in the nozzle 8. Even if there is, the ink can be filled in all the nozzles 8 after the maintenance operation, and the ejection performance can be recovered.

  Then, after performing such a suction operation, before performing the wipe operation by the wipe unit 23, the ink absorption operation by the ink absorber 27 is performed, so that the ink attached to the ink discharge surface 10 is dropped by the suction operation. By preventing adhesion to each part of the apparatus, it is possible to prevent the inside of the apparatus, the platen 3, the recording medium S, and the like from becoming dirty, and melting and corrosion of various parts due to adhesion of ink droplets.

  Further, before the wiping operation by the wiping unit 23 is performed, the ink absorption operation is performed to absorb the ink droplets adhering to the ink ejection surface 10, so that even a small number of wiping operations sufficiently adhere to the ink ejection surface 10. Ink removal can be completed, and an efficient and effective maintenance operation can be performed.

  In the present embodiment, the wipe unit 23 removes ink adhering to the ink discharge surface 10 by pressing the ink absorbing member 39 against the ink discharge surface 10 by the pressing member 43, so that the ink is removed with a blade or the like. Unlike the case where the ejection surface 10 is wiped off, the ink can be removed without damaging the ink ejection surface 10.

  Further, since the ink absorber 27 is formed of any material of felt, a nonwoven fabric made of an olefin-based or polyolefin-based resin, or a high-density fiber, the ink is like an ultraviolet curable ink. Even in the case of a highly viscous ink, ink droplets can be absorbed appropriately, and dissolution due to adhesion of the ink hardly occurs, so that it can withstand long-term use.

  Further, during the ink absorbing operation by the ink absorbing unit 22, a minute gap is formed between the upper end portion of the ink absorber 27 and the ink ejection surface 10, and the ink absorber 27 serves as an ink. Since there is no direct contact with the ejection surface 10, the ink ejection surface 10 is not damaged or does not affect the water repellent treatment applied to the ink ejection surface 10.

  In addition, the inkjet recording apparatus 100 according to the present embodiment has a viscosity at 25 ° C. of 10 to 50 [mPa · s] and a surface tension of 20 to 40 [mN / m] like ultraviolet curable ink. Since high-viscosity ink is used for image recording, a high-definition image can be obtained even on a recording medium S with poor ink absorption, such as a resin film, regardless of the type of recording medium S. Even when such an ink is used, the ink absorbing operation by the ink absorber 27 is performed after the suction operation, and then the wiping operation is performed, thereby effectively removing the ink adhering to the ink ejection surface 10. The meniscus formed at the tip of the nozzle 8 can be properly adjusted. As a result, maintenance can be performed in a state where ink can be normally ejected from each nozzle 8 of the recording head 7, and a high-definition recording operation can be performed.

  In the present embodiment, the bottom 30 of the storage unit 29 that stores the ink absorber 27 is inclined. However, the configuration of the ink absorption unit 22 is not limited to that illustrated here. For example, the shape of the ink absorber 27 itself may be a tapered shape inclined from one end side to the other end side in the longitudinal direction. In this case, for example, the bottom portion 30 of the storage portion 29 that stores the ink absorber 27 is similarly inclined so that the upper end surface of the ink absorber 27 is horizontal with respect to the ink ejection surface 10. To do.

  Further, in the present embodiment, the ink absorbed by the ink absorber 27 is configured to naturally flow to one end side along the inclination of the bottom portion 30 of the storage portion 29. For example, suction is performed in the middle of the ink discharge pipe 32. A pump or the like may be provided so that the ink absorbed by the ink absorber 27 is forcibly sent to the waste liquid tank 33.

In the present embodiment, the first maintenance unit is the suction cap unit 21, and the case where the suction operation by the suction cap unit 21 is performed as the first maintenance operation for filling the nozzle 8 with ink is taken as an example. However, the first maintenance operation is not limited to the suction operation. For example, a purge operation for forcibly discharging ink from the nozzle 8 by a flow pump or the like, or a flushing operation for preliminarily discharging ink (empty discharge) from the nozzle 8 by driving an actuator such as a piezo element may be used.
Further, a maintenance operation combining two or more of the suction operation, the purge operation, and the flushing operation may be performed as the first maintenance operation. Also by these operations, the inside of the nozzle 8 can be filled with ink, and the nozzle shortage or the like can be eliminated.
In addition, when combining a plurality of operations as described above as the first maintenance operation, a plurality of first maintenance units may be provided according to each operation, or all operations are performed by one unit. You may comprise so that it can do. For example, when performing a suction operation, a purge operation, or a flushing operation, an ink receiving portion that receives ink discharged by the purge operation or the like may be provided separately from the suction cap, or a purge operation or the like may be performed on the suction cap. By doing so, the suction cap may also serve as the ink receiving portion.

In the present embodiment, the case where the wipe unit 23 is disposed at a position close to the suction cap unit 21 and the ink absorption unit 22 has been described as an example. However, the position of the wipe unit 23 is not limited to this.
If the ink absorption operation by the ink absorption unit 22 is performed after the suction operation by the suction cap unit 21, most of the ink adhering to the ink discharge surface 10 can be removed. There is no risk of ink dropping on the way and adhering to each part of the apparatus. For this reason, there is no particular inconvenience even if the distance to the wipe unit 23 that performs the next wipe operation after the suction operation by the suction cap unit 21 is long. For example, the wipe unit 23 is attached to the apparatus main body 1. It is good also as a structure provided in the other end side in the main scanning direction X (opposite side which separated the platen 3).
When the wipe unit 23 is provided at a position away from the suction cap unit 21 and the ink absorption unit 22 as described above, the recording head mounted on the carriage 6 is moved to the wipe unit 23 after the suction operation, that is, The ink absorption operation by the ink absorption unit 22 can be performed without stopping the movement of the carriage 6. As a result, the ink absorbing operation can be performed quickly and efficiently.

  Further, the position, number, shape, and the like of the ink absorption unit 22 are not limited to those shown in this embodiment, and for example, the ink absorption unit 22 may be provided adjacent to each suction cap 25.

In this embodiment, the case where four recording heads 7 are provided corresponding to each of the yellow (Y), magenta (M), cyan (C), and black (K) inks is described as an example. The type of ink used in the ink jet recording apparatus and the number of recording heads 7 are not limited to this.
For example, light yellow (LY), light magenta (LM), light cyan (LC), and other color inks such as white ink and transparent ink can be used. In this case, the recording head 7 corresponding to each color is mounted on the carriage 6. Further, the number and arrangement of the recording heads 7 are not limited to those exemplified here, and a larger number of recording heads 7 may be mounted on the carriage 6. Further, for example, one head unit is constituted by four recording heads 7 corresponding to inks of yellow (Y), magenta (M), cyan (C), and black (K), and a plurality of such head units are provided. The position may be shifted in the sub-scanning direction Y.
If the configuration is different from the present embodiment, such as when there are four or more recording heads 7, the suction caps 25 of the suction cap unit 21 are provided according to the number of recording heads 7. In addition, the configuration of the ink absorption unit 22 and the wipe unit 23 such as size and width can be appropriately changed according to the configuration of the recording head.

In the present embodiment, the wipe unit 23 is described as an example having a configuration including the ink absorbing member 39 and the pressing member 43, but the wipe unit can remove ink attached to the ink ejection surface 10. What is necessary is just to be a thing and it is not limited to what was illustrated here.
Further, instead of the wipe unit, a maintenance unit that removes ink by a method other than wipe, such as absorbing ink after a maintenance operation by the suction cap unit 21 and the ink absorption unit 22, may be provided.
Furthermore, the maintenance device 20 may be configured by only the suction cap unit 21 and the ink absorption unit 22, and may be configured without the wipe unit. In this case, the next operation performed after the maintenance operation by the suction cap unit 21 that is the first maintenance unit is, for example, a recording operation.

  In the present embodiment, the serial inkjet recording apparatus 100 using the serial recording head 7 has been described as an example. However, the present invention is also applicable to an inkjet recording apparatus having a line recording head. Is possible. In that case, when the ink absorption unit 22 and the wipe unit 23 are arranged in the apparatus main body 1, the longitudinal direction of the ink absorption unit 22 and the wipe unit 23 is the direction in which the nozzle rows of the recording head are formed. It should be parallel to (the extending direction of the recording head).

  The ink jet recording apparatus according to the present invention may use either an on-demand type or a continuous type recording head 7. In addition, as a discharge method, for example, an electro-mechanical conversion method (for example, a single cavity type, a double cavity type, a bender type, a piston type, a shear mode type, a shared wall type, etc.), an electro-thermal conversion method (for example, , Thermal ink jet type, bubble jet (registered trademark) type), electrostatic suction type (for example, electric field control type, slit jet type, etc.) and discharge type (for example, spark jet type, etc.) The recording head 7 may be used.

  In this embodiment, image recording is performed using ink that is cured by irradiation with ultraviolet rays. However, the ink is not necessarily limited to this, and for example, ultraviolet rays, electron beams, X-rays, and visible rays. The ink may be cured by irradiating light other than ultraviolet rays such as electromagnetic waves such as infrared rays. In this case, a polymerizable compound that is polymerized and cured with light other than ultraviolet light and a photoinitiator that initiates a polymerization reaction between the polymerizable compounds with light other than ultraviolet light are applied to the ink. In the case of using a photocurable ink that is cured by light other than ultraviolet light, a light source that emits the light is applied instead of the ultraviolet light source. Further, image recording may be performed using ink that is cured without being irradiated with light. In this case, it is not necessary to provide an apparatus for irradiating light, and the apparatus configuration can be simplified.

  In addition, it is needless to say that the present invention is not limited to the above embodiment and can be modified as appropriate.

  Next, a second embodiment of the ink jet recording apparatus according to the present invention will be described with reference to FIGS. Note that the second embodiment is different from the first embodiment only in the configuration of the suction cap unit, and therefore, the points that are different from the first embodiment will be described below.

  In the present embodiment, the ink jet recording apparatus includes a recording head 7 (see FIG. 9) having a piezoelectric element such as a piezoelectric element (not shown) as an actuator, as in the first embodiment. The recording head 7 is provided with an ink discharge surface 10 on which an ink discharge port 9 of a nozzle 8 for discharging ink is formed.

In addition, the ink jet recording apparatus includes a maintenance device 50 that performs a maintenance operation on the nozzles 8 and the ink discharge surface 10 of the recording head 7 as in the first embodiment.
FIG. 8 is a perspective view showing the maintenance device 50 in the present embodiment, and FIG. 9 is a front view schematically showing the positional relationship of the maintenance device 50.
As shown in FIG. 8 and FIG. 9, the maintenance device 50 includes a suction cap unit 51 that is a first maintenance unit that sucks ink from the nozzles 8 and fills the nozzles 8 with ink, and a first implementation. An ink absorption unit 22 and a wipe unit 23 similar to those of the embodiment are provided.

  In the present embodiment, the suction cap unit 51 includes four suction caps 55 corresponding to the number of recording heads 7 and a unit support base 54 that supports the suction caps 55, as in the first embodiment. A shutter main body 56 is provided so as to cover the unit support 54 and the suction cap 55.

  On the upper surface in FIG. 9 of the shutter main body 56 (the surface facing the ink ejection surface 10 of the recording head 7 during the maintenance operation), four openings 57 are provided corresponding to the suction cap 55. The opening 57 is formed to have a size larger than that of the suction cap 55, and during the suction operation, the suction cap 55 is raised and exposed to the outside of the shutter main body 56 from the opening 57, and the ink discharge surface of the recording head 7. 10 can be contacted.

Each opening 57 is provided with a shutter plate 58 that is movable by a drive source (not shown) and closes the opening 57.
The shutter plate 58 retracts to a position where the opening 57 is not blocked during the suction operation, and closes the opening 57 except during the suction operation so that the suction cap 55 is not irradiated with active energy rays such as ultraviolet rays. It is designed to shield.

As shown in FIG. 9, in the ink absorption unit 22, the upper end portion of the ink absorber 27 is located at the uppermost portion of the suction cap unit 51 and the wipe unit 23 (the portion close to the ink discharge surface 10) during non-maintenance. It is arranged so as to be located at a position higher than the position (position close to the ink ejection surface 10).
In the present embodiment, the uppermost portion of the suction cap unit 21 is the upper surface of the shutter main body 56, and the uppermost portion of the wipe unit 23 is the upper end of the roller member 46. When the height at which the upper surface of the shutter main body 56 and the upper end of the roller member 46 are located during non-maintenance is α and the position of the upper end of the ink absorbing unit 22 is β, the upper end of the ink absorbing unit 22 The position β is higher than α.

  Further, as shown in FIG. 9, the ink absorbing unit 22 has a small gap (gap γ in FIG. 9) between the upper end portion of the ink absorber 27 and the ink ejection surface 10 during the ink absorbing operation. It is arranged at the position to be formed. The size of the gap γ is not particularly limited, but is preferably about the same as the distance between the recording medium S and the ink ejection surface 10 when performing the recording operation, for example, about 1.5 mm to 2 mm. preferable.

  Since other configurations are the same as those of the first embodiment, the same members are denoted by the same reference numerals and description thereof is omitted.

  Next, the operation in this embodiment will be described.

  When performing the maintenance operation, the carriage 6 moves above the maintenance device 50. Then, the shutter plate 58 of the suction cap unit 51 is retracted to a retracted position where the opening 57 is not blocked, and the suction cap 55 is raised and exposed from the opening 57 to the outside of the shutter main body 56. When the suction cap 55 comes into contact with the ink ejection surface 10 of the recording head 7, the ink suction operation by the suction cap unit 51 is performed.

Thereafter, the ink droplets adhering to the ink ejection surface 10 of the recording head 7 when the carriage 6 moves in the movement direction A and passes above the ink absorption unit 22 are absorbed by the ink absorber 27. Further, when the recording head 7 moves above the wipe unit 23, the ink absorbing member 39 is pressed against the ink discharge surface 10 by the reciprocating movement of the pressing member 43, and a maintenance operation by wiping is performed.
As a result, the ink adhering to the ink ejection surface is absorbed and removed by the ink absorbing member 39 and the meniscus formed at the tip of the nozzle 8 can be adjusted.

  Since other operations are the same as those of the first embodiment, description thereof is omitted.

As described above, according to the present embodiment, the shutter cap 58 is provided in the suction cap unit 51 so that ultraviolet rays and the like are not irradiated except during the suction operation. Even if the ultraviolet irradiation device 11 is not turned off, the ink attached to the suction cap can be prevented from being cured by the ultraviolet irradiation.
Even in such a configuration, since the upper end portion of the ink absorber 7 is located higher than the shutter main body 56, when the carriage 6 or the like passes above the ink absorber 7, the shutter main body 56 or the like. Therefore, the maintenance operation can be performed appropriately.

  In the present embodiment, the shutter cap 58 is provided in the suction cap unit 51. However, it is sufficient if a mechanism that can prevent the suction cap 55 from being irradiated with ultraviolet rays other than during the suction operation is sufficient. Is not limited to those exemplified here.

  In addition, it is the same as that of 1st Embodiment that this invention is not limited to this embodiment.

1 is a perspective view of an ink jet recording apparatus according to a first embodiment. It is a perspective view which shows the principal part structure of the maintenance apparatus provided in the inkjet recording device shown in FIG. It is a front view which shows the principal part structure of the maintenance apparatus shown in FIG. It is a perspective view which shows the principal part structure of the ink absorption unit provided in the maintenance apparatus shown in FIG. It is a side view which shows a part of wipe unit provided in the maintenance apparatus shown in FIG. It is a front view of the maintenance apparatus which shows the suction operation by a suction cap unit. FIG. 7A is a diagram illustrating a state in which the carriage moves to the next operation after the suction operation, and FIG. 7B is a diagram illustrating an ink absorption operation by the ink absorption unit. It is a perspective view which shows the principal part structure of the maintenance apparatus in 2nd Embodiment. It is a front view which shows the principal part structure of the maintenance apparatus shown in FIG.

Explanation of symbols

7 Recording Head 8 Nozzle 9 Ink Ejecting Port 10 Ink Ejecting Surface 20 Maintenance Device 21 Suction Cap Unit 22 Ink Absorbing Unit 23 Wipe Unit 27 Ink Absorber 28 Absorber Holding Unit 29 Storage Unit 32 Ink Discharge Pipe 33 Waste Liquid Tank 39 Ink Absorbing Member 43 Pressing member 56 Shutter body 58 Shutter plate 100 Inkjet recording apparatus A Moving direction S Recording medium X Main scanning direction Y Sub-scanning direction γ Gap

Claims (7)

A recording head having a nozzle for ejecting ink and an ink ejection surface provided with an ink ejection port of the nozzle;
A maintenance device for maintaining the recording head,
The maintenance device includes a first maintenance unit that performs a first maintenance operation for filling the nozzles with ink, and a downstream side of the first maintenance unit in the moving direction of the recording head after the first maintenance operation. And an ink absorbing unit provided with an ink absorber that contacts and absorbs ink adhering to the ink discharge surface in a non-contact state with the ink discharge surface. apparatus.   The ink absorbing unit performs an ink absorbing operation on the recording head without stopping movement of the recording head after the first maintenance operation on the recording head. 2. An ink jet recording apparatus according to 1.   3. The first maintenance unit is configured to perform a maintenance operation in which any one of an ink suction operation, a purge operation, and a flushing operation, or a combination of two or more thereof is performed. 2. An ink jet recording apparatus according to 1.   The inkjet recording apparatus according to claim 1, wherein the ink absorption unit is connected to a waste liquid storage unit that receives the absorbed ink.   The absorber that absorbs the ink is formed of any material of felt, a nonwoven fabric made of an olefin-based or polyolefin-based resin, or a high-density fiber. The ink jet recording apparatus according to claim 4.   6. The ink according to claim 1, wherein the ink has a viscosity at 25 ° C. of 10 to 50 [mPa · s] and a surface tension of 20 to 40 [mN / m]. 2. An ink jet recording apparatus according to 1.   The inkjet recording apparatus according to claim 1, wherein the ink contains an activation energy ray-curable compound, and the activation energy is ultraviolet light.

Images