JP2018149761A - Liquid discharge unit and apparatus for discharging liquid - Google Patents

Abstract

Provided is a liquid discharge unit capable of preventing a medium and the inside of an apparatus from being contaminated by dirt removed from a cap member constituting a maintenance / recovery mechanism of a liquid discharge head. A liquid discharge head 401, a cap member 402, a suction unit 430, and a cap cleaning member 410, and at least a maintenance / recovery mechanism 440 for maintaining and recovering the state of the liquid discharge head 401 are provided. Cap member moving means for moving the member 402 between a facing position 403 facing the nozzle surface 401a and a retracting position 404 not facing the nozzle surface 401a, and the cap member 402 are arranged on the base portion (cap rotating base 406). A cap member rotating means that rotates about a rotation shaft 408 provided and reverses upside down at the retracted position 404, and the cap nip portion that faces downward at the retracted position 404 is disposed below. It is cleaned by the cap cleaning member 410. [Selection] Figure 5

Description

  The present invention relates to a liquid discharge unit and an apparatus for discharging liquid.

  In an apparatus for ejecting liquid, a liquid ejection head that ejects liquid onto a medium and a mechanism for maintaining and recovering the state of the nozzles of the liquid ejection head are provided. As a member constituting such a maintenance and recovery mechanism, there is a protection / suction cap. The protective / suction cap is used as a moisturizing means during nozzle cleaning and printing.

  As a protective / suction cap (hereinafter simply referred to as “cap”), for example, a cap-like absorber is provided in the cap, and when the nozzle surface of the liquid discharge head is capped, the absorber absorbs ink adhering to the nozzle. An embodiment is known. The ink absorbed by the absorber in the cap is removed and discharged by a suction pump or the like connected to the cap.

  The ink sucked from the nozzle surface may adhere to the cap nip portion including the contact portion with the nozzle surface of the cap. For this reason, when the capping is performed again, the ink attached to the cap nip portion may reattach to the nozzle surface. If the ink reattached to the nozzle surface is left unattended, the ink will thicken by drying and reduce the cleanliness during maintenance. Further, when this state progresses, ink accumulation occurs, and the sealing performance at the time of capping is lowered, which may lead to suction failure and the like.

On the other hand, there has been proposed a technique that removes dirt adhering to the cap and prevents reattachment of dirt to the nozzle surface (see, for example, Patent Document 1).
Patent Document 1 discloses a configuration in which ink adhering to a nip portion of a cap is removed by bringing the cap member into contact with a porous absorber (cap cleaning member).

  In the maintenance / recovery device of Patent Document 1, since the absorber is installed above the retreat position of the cap member, the cap member is lifted by the cap cam to be brought into contact with the absorber to remove dirt. In this way, the absorber is installed above the cap member, and the contact surface (lower surface) with the cap member is open, so that the ink absorbed by the absorber drips or adheres. It may fall.

  That is, there is a problem that the dirt of the cap member removed by the absorber contaminates the medium and the inside of the apparatus.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid discharge unit capable of preventing the medium and the inside of the apparatus from being contaminated by dirt removed from the cap member constituting the maintenance and recovery mechanism of the liquid discharge head.

  In order to achieve such an object, a liquid discharge unit according to the present invention includes a liquid discharge head having a plurality of nozzles for discharging a liquid to a conveyed medium, and a cap for capping the nozzle surface of the liquid discharge head. A cap member, which comprises a base portion on which the cap is placed, is disposed so as to be detachable from the liquid discharge head, suction means connected to the inside of the cap, and the nozzle surface of the cap. And a cap cleaning member that cleans the cap nip including the contact portion, and a liquid discharge unit that includes at least a maintenance / recovery mechanism that performs maintenance / recovery of the state of the liquid discharge head, wherein the cap member is connected to the nozzle surface. A cap member moving means for moving between a facing position facing the nozzle and a retracted position not facing the nozzle surface, and the cap portion And a cap member rotating means for rotating up and down in the retracted position, and the cap nip portion facing downward at the retracted position. The cap is cleaned by the cap cleaning member disposed below.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid discharge unit which can prevent that a medium and the inside of an apparatus are contaminated with the dirt removed from the cap member which comprises the maintenance recovery mechanism of a liquid discharge head can be provided.

It is a side view which shows an example of the whole structure of the apparatus which discharges the liquid which concerns on this invention. It is a top view which shows an example of the liquid discharge unit which concerns on this invention. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 1st embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 1st embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 1st embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 2nd embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 2nd embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 2nd embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 3rd embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 4th embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 4th embodiment. It is a schematic block diagram of an example of the liquid discharge unit which concerns on 4th embodiment.

  Hereinafter, a liquid discharge unit according to the present invention and a device for discharging a liquid including the liquid discharge unit will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

(Device for discharging liquid)
The apparatus for discharging a liquid of the present invention includes the liquid discharge unit of the present invention described later.
An apparatus 1000 for discharging a liquid according to an embodiment of the present invention will be described with reference to FIG.

  In the apparatus 1000 for ejecting liquid shown in FIG. 1, continuous paper wound in a roll shape (hereinafter referred to as “roll paper Md”) is used as a medium, but the medium that can be used in the apparatus for ejecting liquid is roll paper. It is not limited. That is, the medium may be cut paper. In addition, the media that can be used in the device for discharging liquid can be attached to plain paper, fine paper, thin paper, cardboard, recording paper and roll paper, OHP sheet, synthetic resin film, metal thin film and other surfaces. Including things. Here, the roll paper is continuous paper (continuous form paper, continuous form) in which cuttable perforations are formed at a predetermined interval. Further, a page (page) on the roll paper is, for example, an area sandwiched between perforations at a predetermined interval.

  As shown in FIG. 1, an apparatus 1000 for discharging liquid according to the present embodiment includes a carry-in means 100 for carrying in a roll paper Md as a medium, a pre-processing means 200 for pre-processing the roll paper Md carried in, Drying means 300 for drying the processed roll paper Md. The apparatus 1000 for discharging liquid includes a liquid discharge unit 400 for discharging liquid onto the surface of the roll paper Md, a post-processing unit 450 for post-processing the roll paper Md discharged with liquid, and post-processing for discharging liquid. A drying unit 310 that dries the roll paper Md that has been processed, and a carry-out unit 600 that carries out the roll paper Md that has been post-processed. Furthermore, the apparatus 1000 for ejecting liquid includes a control unit 700 that controls the operation of the apparatus 1000 for ejecting liquid.

  The apparatus 1000 that discharges liquid feeds the roll paper Md to the preprocessing means 200 by the carry-in means 100, and preprocesses and dries the surface of the roll paper Md by the preprocessing means 200 and the drying means 300. In addition, the apparatus 1000 that discharges liquid discharges the liquid onto the surface of the roll paper Md that has been pretreated and dried by the pretreatment unit 200 and the drying unit 300 by the liquid ejection unit 400. Furthermore, the apparatus 1000 that discharges liquid uses the post-processing unit 450 and the drying unit 300 to post-process and dry the roll paper Md from which the liquid has been discharged from the liquid discharge unit 400. Thereafter, the apparatus 1000 that discharges the liquid winds and discharges the post-processed and dried roll paper Md by the unloading means 600. The above series of operations is controlled by the control means 700.

  Note that the apparatus 1000 that discharges the liquid can be configured so as not to include any one or more of the pre-processing means 200 and the like depending on the type of the medium from which the liquid is discharged.

The apparatus for discharging the liquid is not limited to the above-described embodiment as long as the apparatus includes the liquid discharge unit of the present invention and drives the liquid discharge head to discharge the liquid.
Moreover, the apparatus which discharges a liquid is not limited to what can visualize significant images, such as a character and a figure, by the discharged liquid. For example, what forms a pattern etc. which does not have a meaning in itself, and what forms a three-dimensional image are also included.

  The above-mentioned “applicable liquid” means a liquid (medium) to which the liquid can adhere at least temporarily, and adheres and adheres, adheres and penetrates, and the like. Specific examples include recording media such as paper, recording paper, recording paper, film, and cloth, electronic parts such as electronic substrates and piezoelectric elements, powder layers (powder layers), organ models, and test cells. Yes, unless specifically limited, includes everything that the liquid adheres to.

  The material of the above-mentioned “material to which liquid can adhere” is not limited as long as liquid such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics can be adhered even temporarily.

  The “liquid” is not particularly limited as long as it has a viscosity and surface tension that can be ejected from the head, and the viscosity is 30 mPa · s or less at room temperature, normal pressure, or by heating and cooling. Preferably there is. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , Edible materials such as natural pigments, solutions, suspensions, emulsions, and the like. These include, for example, inkjet inks, surface treatment liquids, components of electronic devices and light emitting devices, and formation of electronic circuit resist patterns. It can be used in applications such as liquids for use, three-dimensional modeling material liquids, and the like.

(Liquid discharge head)
FIG. 2 is a plan view of a liquid discharge unit 400 constituting the apparatus 1000 for discharging a liquid shown in FIG. 1. In the liquid discharge unit of this embodiment, a full-line liquid discharge head 401 is used.
As shown in FIG. 2, four liquid ejection heads 401K, 401C, 401M, and 401Y are arranged from the upstream side in the transport direction Xm of the roll paper Md that is a recording medium. The subscripts K, C, M, and Y in the liquid discharge head indicate the color of the ink, and indicate black, cyan, magenta, and yellow, respectively. The color order of K, C, M, and Y is not limited to the mode shown in FIG. The liquid discharge head may be green, red, light cyan, and / or other colors, or may be a single color (for example, only black).

  Here, in the black (K) liquid discharge head 401K, four head units 401K-1, 401K-2, 401K-3, and 401K-4 are staggered in a direction perpendicular to the transport direction Xm of the roll paper Md. Is arranged. Accordingly, the liquid discharge head 401K can form a black (K) image over the entire image forming area (printing area) of the roll paper Md. The configurations of the other liquid discharge heads 401C, 401M, and 401Y are the same as the configuration of the black (K) liquid discharge head 401K.

  Retreat positions 404K, 404C, 404M, and 404Y are provided in the medium transport direction of each liquid ejection head.

  The energy generation source for discharging the liquid of the liquid discharge head 401 constituting the liquid discharge apparatus of the present embodiment is not particularly limited, and for example, a piezoelectric actuator (laminated piezoelectric element and thin film piezoelectric element), heating resistor Examples include a thermal actuator that uses an electrothermal conversion element such as a body, and an electrostatic actuator that includes a diaphragm and a counter electrode.

(Liquid discharge unit)
The liquid discharge unit is an assembly of functional parts and mechanisms integrated with the above-described liquid discharge head, and is an assembly of parts related to liquid discharge. Combinations are included.
An assembly of parts related to liquid discharge in which other functional parts and mechanisms are integrated with the four liquid discharge heads 401K, 401C, 401M, and 401Y shown in FIG. The liquid discharge unit 400 drives the liquid discharge heads 401K, 401C, 401M, and 401Y to discharge liquid.
Here, the term “integrated” refers to, for example, a liquid discharge head, a functional component, and a mechanism that are fixed to each other by fastening, adhesion, engagement, etc., and one that is held movably with respect to the other. Including. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

[First embodiment]
The liquid discharge unit of this embodiment will be described with reference to FIGS.
The liquid ejection unit 400 according to the present embodiment includes a liquid ejection head 401 having a plurality of nozzles 401b that eject liquid to a conveyed medium, and a cap 402a and a cap 402a that cap the nozzle surface 401a of the liquid ejection head 401. And a suction member 430 connected to the inside of the cap 402a. The cap member 402 includes a base portion (cap moving base 405 and cap rotating base 406) on which the liquid discharge head 401 is placed. And a cap cleaning member 410 that cleans a cap nip including a contact portion of the cap 402a with the nozzle surface 401a, and at least a maintenance / recovery mechanism 440 that maintains and recovers the state of the liquid ejection head 401. Opposing position where the member 402 faces the nozzle surface 401a Cap member moving means for moving between 403 and a retreat position 404 that does not oppose the nozzle surface 401a, and the cap member is rotated about a rotating shaft 408 disposed on the base portion (cap rotating base 406) 402. And a cap member rotating means that is turned upside down at the retracted position 404, and the cap nip portion that faces downward at the retracted position 404 is cleaned by a cap cleaning member 410 disposed below.
Further, the cap cleaning member 410 accommodates a cleaning unit 411.

  In the following liquid discharge unit diagram, only one liquid discharge head is shown among the liquid discharge heads 401K, 401C, 401M and 401Y (hereinafter referred to as “liquid discharge head 401”) shown in FIG. . In addition, although two rows of liquid ejection heads 401 are described in one head unit, this is because of the staggered arrangement in FIG.

The liquid discharge unit 400 of the present embodiment includes a cap moving base 405 and a cap rotation base 406 as a base portion of the cap member 402. The cap moving means includes an endless conveying belt member 433 wound around rollers 431 and 432, and the cap rotating means includes a rotating shaft 408 and a motor 409. The suction means 430 has a suction pump 407.
The control means 700 constituting the apparatus for discharging liquid shown in FIG. 1 is also means for controlling the operation of the constituent members of the liquid discharge unit 400, and includes a cap cleaning member 410, a suction pump 407, a motor 409, and a transport belt member 433. The operation of the rollers 431 and 432 for driving the motor is controlled.

The cap 402a is a member that keeps the nozzle surface 401a moist by contacting and closing (capping) the nozzle surface 401a of the liquid discharge head 401, or sucking the liquid from the nozzle 401b by the connected suction means 430. is there.
The suction pump 407 constituting the suction means 430 is connected to the inside of the cap 402a, and the liquid is sucked from the nozzle 401b by driving the suction pump 407 with the cap 402a capping the nozzle surface 401a. The sucked liquid is discharged to the waste liquid tank 500 and accumulated.

The cap moving means moves the cap member 402 between a facing position 403 facing the nozzle surface 401a and a retracting position 404 not facing the nozzle surface 401a in the sub-scanning direction along the medium transport direction.
3 shows a state in which the cap member 402 has moved to the facing position 403, which is a capping position, and FIGS. 4 and 5 show a state in which the cap member has moved to the retracted position 404. The capping of the nozzle surface 401a of the liquid discharge head 401 is performed at the position shown in FIG.

As shown in FIG. 5, the cap member 402 moved to the retracted position 404 is turned upside down by the cap member rotating means, and the cap nip portion facing downward is moved by the cap cleaning member 410 disposed below. To be cleaned. Specifically, by driving the motor 409, the cap rotation base 406 rotates about the rotation shaft 408, and the cap 402a is turned upside down.
The cap cleaning member 410 is raised with respect to the cap member 402 at the retracted position 404, and the cap 402a and the cleaning means 411 are brought into contact with each other. By this operation, dirt on the cap nip portion including the contact portion of the cap 402a with the nozzle surface 401a is removed.

  Since the liquid discharge unit 400 of the present embodiment is configured to clean the cap cleaning member 410 by installing it below the cap member 402, the ink or deposits removed by the cleaning unit 411 may drop or drop. In addition, the medium and the inside of the apparatus are not contaminated by the dirt removed from the cap member 402.

As the cleaning means 411, a porous material such as a cleaning liquid or a sponge impregnated with the cleaning liquid can be used. By using such a cleaning means, the inside of the cap 402a is moisturized during cleaning, and it is possible to prevent the adhering liquid from becoming solid, and the cleaning ability is improved as compared with the case of using a dry cleaning means. be able to.
In addition, when a porous body is used as the cleaning unit 411, the cap nip portion may repeatedly come into contact with the same position, which may cause re-attachment of dirt. However, the cleaning unit 411 may cause re-attachment. Can be prevented.
The cleaning liquid is not particularly limited.

The cap nip includes vibration means for vibrating the cleaning means 411 housed in the cap cleaning member 410, and includes a contact surface between the cleaning means 411 and the nozzle surface 401a of the cap 402a by vibration excited by the vibration means. It can be set as the structure which a part slides.
The vibrating means is not particularly limited, and known ones can be used, and examples thereof include an ultrasonic generator.
By cleaning the cleaning means 411, the cleaning ability can be improved.
In addition, when a porous body is used as the cleaning unit 411, there is a risk of causing wear and damage due to sliding with the cap nip portion due to vibration, but this is prevented by using a cleaning liquid as the cleaning unit 411. be able to.

  The suction unit 430 preferably performs suction in the cap 402a before the cap member 402 is turned upside down. By removing the liquid in the cap 402a before turning upside down, it is possible to prevent the liquid from dropping to a place other than the cap cleaning member 410.

Further, it is preferable that the cap cleaning member 410 is arranged so as to be movable in the sub-scanning direction along the medium conveyance direction in accordance with the movement and rotation of the cap member 402.
At least when the cap member 402 is turned upside down, the liquid or deposits in the cap 402a may drop or drop to a place other than the cap cleaning member 410 by being disposed below the cap member 402. Can be prevented.

[Second Embodiment]
The liquid discharge unit according to the present embodiment will be described with reference to FIGS.
In the liquid discharge unit according to the present embodiment, the cap member moving unit includes the same rotating mechanism as the cap member rotating unit. That is, the cap member 402 can be moved to the retracted position 404 only by a rotation operation.

  As shown in FIGS. 6 to 8, the base portion of the cap member in the present embodiment includes a cap rotation base 406 and is provided at the end of the cap rotation base 406 as cap member rotation means that is also a cap member moving means. A rotation shaft 412 and a motor 413 are provided. By driving the motor 413, the cap rotation base 406 is rotated, and the cap 402a is turned upside down at the retracted position 404.

The rotating shaft 412 is provided with a torsion spring and a stopper, and when the motor 413 is not driven, as shown in FIG. 6, the cap 402a is disposed at the facing position 403 that is the capping position.
By driving the motor 413, as shown in FIGS. 7 and 8, the cap rotation base 406 is rotated around the rotation shaft 412 and the cap member 402 is moved to the retracted position 404.
As shown in FIG. 8, the cap member 402 moved to the retracted position 404 is turned upside down. The cap cleaning member 410 disposed below is raised, and the cap nip portion facing downward is brought into contact with the cleaning means 411. By this operation, dirt on the cap nip portion including the contact portion of the cap 402a with the nozzle surface 401a is removed.

  Similar to the first embodiment described above, since the cap cleaning member 410 is installed below the cap member 402 for cleaning, the ink and deposits removed by the cleaning means 411 drips or drops. In addition, the medium and the inside of the apparatus are not contaminated by the dirt removed from the cap member 402.

[Third embodiment]
The liquid discharge unit of this embodiment will be described with reference to FIG.
The liquid discharge unit according to the present embodiment includes a guide rail 415 that defines a rotation path of the cap member 402, and a guide roller in which a base portion (cap rotation base 406) of the cap member 402 moves along the guide rail 415. 423.

  As shown in FIG. 9, in the present embodiment, a semicircular guide rail 415, a guide roller 423, and a second motor 414 are provided to the configuration of the second embodiment described above, and the motor 413 and the second motor 414 are provided. By driving the motor 414, the rotation shaft 412 and the guide roller 423 rotate, the guide roller 423 moves along the guide rail 415, and the cap rotation base 406 rotates. By providing two motors, the torque of each motor can be reduced. Note that the motor 413 may be omitted. In this case, since the position of the second motor 414 is away from the rotation shaft 412 serving as the rotation center, the necessary torque can be reduced as compared with the above-described embodiment.

  Stoppers may be provided at both ends of the guide rail 415. By providing the stopper, the facing position 403 and the retracted position 404 can be defined without providing the rotating shaft 412 with a stopper.

  Further, the guide rail 415 can be a rack gear and the guide roller 423 can be a pinion gear. With such a configuration, it is possible to provide posture stability of the cap rotation base 406 when the cap member 402 is rotated.

  Also in the present embodiment, the cap member 402 is turned upside down at the retracted position 404, and the cap nip portion facing downward is cleaned by the cap cleaning member 410 disposed below. That is, the cap cleaning member 410 is raised with respect to the cap member 402 at the retracted position 404, and the cap 402a and the cleaning means 411 are brought into contact with each other, whereby the dirt on the cap nip portion is removed.

  Similar to the above-described embodiment, the present embodiment also has a configuration in which the cap cleaning member 410 is installed below the cap member 402 for cleaning, so that the ink and deposits removed by the cleaning means 411 may drop or drop. Therefore, the medium and the inside of the apparatus are not contaminated by the dirt removed from the cap member 402.

[Fourth embodiment]
The liquid discharge unit according to the present embodiment will be described with reference to FIGS.
In the liquid discharge unit of the present embodiment, the cap member moving unit includes a transport belt member 433 that moves the cap member 402 in the sub-scanning direction along the medium transport direction, and the cap member rotating unit includes the cap member 402. A pinion gear 416 disposed on the base portion (cap rotation base 406) of the base plate and a rack gear 417 disposed at a position where the pinion gear 416 meshes with the movement of the cap member 402. The cap rotation base 406 can be rotated by the pinion gear 416 and the rack gear 417.

  FIG. 10 shows a state where the cap member 402 is at the facing position 403. A rotation shaft connected coaxially to the pinion gear 416 is provided, and a torsion spring and a stopper are provided on the rotation shaft. When no torque is applied to the cap rotation base 406, the cap member 402 is disposed at the facing position 403.

  As shown in FIG. 11, the cap rotation base 406 rotates when the cap member 402 moves in the medium conveyance direction by the cap movement base 405 and the conveyance belt member 433 and the pinion gear 416 engages with the rack gear 417. Then, as shown in FIG. 12, the cap member 402 is turned upside down at the retracted position 404. The cap nip portion turned downward is cleaned by a cap cleaning member 410 disposed below. FIG. 12 shows a state in which the cap nip portion and the cleaning unit 411 are not in contact with each other. However, the cap cleaning member 410 is raised with respect to the cap member 402 at the retracted position 404, so that the cap 402 a and the cleaning unit 411 are The cap nip portion can be removed by contacting the cap nip.

  According to this embodiment, the cap member 402 can be rotated without providing a motor.

  Similar to the above-described embodiment, the present embodiment also has a configuration in which the cap cleaning member 410 is installed below the cap member 402 for cleaning, so that the ink and deposits removed by the cleaning means 411 may drop or drop. Therefore, the medium and the inside of the apparatus are not contaminated by the dirt removed from the cap member 402.

400 Liquid discharge unit 401 Liquid discharge head 401a Nozzle surface 401b Nozzle 402 Cap member 402a Cap 403 Opposed position 404 Retraction position 405 Cap moving base 406 Cap rotation base 407 Suction pump 408, 412 Rotating shaft 409, 413 Motor 410 Cap cleaning member 411 Cleaning Means 415 Guide rail 416 Pinion gear 417 Rack gear 423 Guide roller 430 Suction means 431, 432 Roller 433 Conveying belt member 440 Maintenance / recovery mechanism 1000 Device for discharging liquid

JP 2009-292030 A

Claims (10)

A liquid ejection head having a plurality of nozzles for ejecting liquid to a conveyed medium; and
A cap member for capping the nozzle surface of the liquid discharge head and a base portion on which the cap is placed, and a cap member arranged to be detachable from the liquid discharge head, and a suction connected to the inside of the cap A liquid discharge unit having at least a maintenance and recovery mechanism that has a means and a cap cleaning member that cleans a cap nip portion including a contact portion of the cap with the nozzle surface, and performs maintenance and recovery of the state of the liquid discharge head Because
Cap member moving means for moving the cap member between a facing position facing the nozzle surface and a retracted position not facing the nozzle surface;
A cap member rotating means for rotating the cap member around a rotation shaft disposed in the base portion, and turning the cap member upside down at the retracted position;
The liquid ejection unit, wherein the cap nip portion that is directed downward at the retracted position is cleaned by the cap cleaning member disposed below.   The liquid discharge unit according to claim 1, wherein the cap member moving unit includes the same rotation mechanism as the cap member rotation unit. A guide rail that defines a turning path of the cap member;
The liquid discharge unit according to claim 1, wherein the base portion of the cap member includes a guide roller that moves along the guide rail.   The liquid discharge unit according to claim 3, wherein the guide rail is a rack gear, and the guide roller is a pinion gear. The cap member moving means has a transport belt member that moves the cap member in a sub-scanning direction along the transport direction of the medium,
The said cap member rotation means has the pinion gear arrange | positioned by the said base part of the said cap member, and the rack gear arrange | positioned in the position meshed | engaged by the movement of the said cap member. The liquid discharge unit described.   The liquid discharge unit according to claim 1, wherein the cap cleaning member has a porous body impregnated with a cleaning liquid as a cleaning unit.   The liquid discharge unit according to claim 1, wherein the cap cleaning member has a cleaning liquid as a cleaning unit. Comprising vibration means for vibrating the cleaning means housed in the cap cleaning member;
8. The cap nip portion including a contact surface between the cleaning unit and the nozzle surface of the cap slides due to vibration excited by the vibration unit. 9. Liquid discharge unit.   9. The liquid ejection unit according to claim 1, wherein the cap cleaning member moves in a sub-scanning direction along a conveyance direction of the medium in accordance with the movement and rotation of the cap member. .   An apparatus for ejecting liquid, comprising the liquid ejection unit according to claim 1.