JP2003266716A - Inkjet head, method for cleaning head, and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a cleaning effect for an ink discharge face without damaging the face and to prevent color mixture of a cleaning member in an inkjet head which discharges ink from ink discharge holes onto a recording medium. <P>SOLUTION: In the method for cleaning a printing head 4 having an array of ink discharge holes formed for discharging the ink of a plurality of colors, a cleaning roller 7 formed of an elastic material in a cylindrical shape and having its section circumferential length πD set longer than a distance L between the first array Y and the last array K of the ink discharge holes formed at the ink discharge face 6 of the printing head 4 is moved in touch with the ink discharge face 6, and ink in the ink discharge holes is sucked by a pressure change in the ink discharge holes at this moving time. The cleaning effect for the ink discharge face 6 is improved without damaging the face, and at the same time, the color mixture of the cleaning member can be prevented. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet head for ejecting ink for forming an image from an ink ejection hole onto a recording medium, a head cleaning method, and an image forming apparatus.
In addition, the present invention relates to an inkjet head, a head cleaning method, and an image forming apparatus that improve the cleaning effect in the vicinity of the ink ejection holes and prevent color mixture of ink during cleaning.

[0002]

2. Description of the Related Art Ink jet type image forming apparatuses, such as ink jet printers, are widely used because of low running cost, easy colorization of printed images, and easy size reduction of the apparatus. This ink jet printer is designed to perform image recording by ejecting a small amount of ink from a minute ink ejection hole provided on the ink ejection surface of the print head, and does not perform a printing operation continuously for a long time. When the ink is not ejected from the ink ejection holes of the above, the ink adhering to the vicinity of the ink ejection holes on the ink ejection surface may evaporate and dry, thicken, and solidify due to the previous printing operation. Ink ejection becomes difficult.

Therefore, conventionally, a blade made of slightly hard rubber or the like is pressed against the ink ejection surface of the print head and slid on the ink ejection surface to adhere to the ink ejection surface to increase the viscosity. The print head is cleaned by removing (wiping) the solidified ink. In this regard, JP-A-57-349
Japanese Patent Laid-Open No. 69 discloses a technique in which a plurality of blades are attached to a rotary shaft and rotated to further enhance the wiping effect.

Further, Japanese Laid-Open Patent Publication No. 56-101866 discloses a technique for preventing non-ejection of ink by sucking and removing ink, dust and the like in the ink ejection hole using a suction pump. .

[0005]

However, in such a conventional technique, a blade made of a slightly hard rubber or the like is pressed against the ink ejection surface of the print head and slid on the ink ejection surface. Since the ink adhering to the ink ejection surface is wiped, a large force is applied to the ink ejection surface by the blade, which may damage the ink ejection surface. In addition, with the above-mentioned blade, it is necessary to rely only on the wiping effect, but ink may remain in the ink ejection holes only by wiping. Even when a plurality of blades are used, there is a problem that the ink ejection surface may be damaged and the ink may remain in the vicinity of the ink ejection hole as in the above case.

When the suction pump is used to suck and remove the ink, dust, and the like in the ink discharge hole, it is necessary to suck a little more ink in the ink discharge hole, which wastes ink from the ink jet head. There was a case that was consumed.

In view of this, the present invention addresses such problems and aims to improve the cleaning effect in the vicinity of the ink ejection holes without damaging the ink ejection surface and prevent color mixture of ink during cleaning. An object is to provide an inkjet head, a head cleaning method, and an image forming apparatus.

[0008]

In order to achieve the above object, an ink jet head according to the present invention is a print head having an ink ejection surface provided with a row of ink ejection holes for ejecting a plurality of colors of ink for each color. An ink jet head for ejecting ink for forming an image on a recording medium from the ink ejection hole, which is formed into a columnar shape with an elastic material, and has a cross-sectional perimeter of the ink of the print head. A cleaning member formed longer than the distance between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes provided on the ejection surface, and the cleaning member on the ink ejection surface of the print head. A state in which the outer peripheral surface of the cleaning member is in contact with the ink ejection surface. The pressure change in the ink discharge hole when rotating movement is obtained so as to suck the ink in the ink discharge hole.

With this structure, the material is formed into a columnar shape with an elastic material, and the length of the circumference of the cross section is in the direction orthogonal to the column direction of the ink ejection holes provided on the ink ejection surface of the print head. A cleaning member, which is formed longer than the distance between the first row and the last row, is relatively moved while being in contact with the ink ejection surface of the print head, and the outer peripheral surface of the cleaning member is the ink ejection surface. The ink in the ink ejection hole is sucked and removed by the change in pressure in the ink ejection hole when the ink is rotated while moving in contact with the ink ejection hole. As a result, it is possible to improve the cleaning effect in the vicinity of the ink ejection holes without damaging the ink ejection surface of the print head, and to reapply another color at the contact portion where the ink ejection holes of a predetermined color have been cleaned once. There is no need to clean the ink ejection holes.

The cleaning member has a large number of small holes formed on its outer peripheral surface. As a result, the ink sucked from the ink ejection holes due to the pressure change in the ink ejection holes when the outer peripheral surface of the cleaning member is rotationally moved in contact with the ink ejection surface of the print head The capillarity of the small holes is caught in the small holes, and is reliably removed and cleaned without being left on the ink ejection surface.

The head cleaning method according to the present invention is a head cleaning method for a print head having an ink ejection surface provided with a row of ink ejection holes for ejecting a plurality of colors of ink for each color, and has elasticity. The material is formed into a columnar shape, and the length of the cross-section perimeter thereof is more than the distance between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes provided on the ink ejection surface of the print head. When the outer peripheral surface of the cleaning member formed long is relatively rotated while being in contact with the ink ejection surface of the print head, the outer peripheral surface of the cleaning member contacts the ink ejection surface and moves. The ink in the ink ejection hole is sucked by the pressure change in the ink ejection hole.

By carrying out such a method, a pressure change in the ink ejection hole when the outer peripheral surface of the cleaning member is rotationally moved in a state of being in contact with the ink ejection surface of the print head causes a change in the ink ejection hole. Suction and remove the ink. As a result, it is possible to prevent the ink ejection surface of the print head from being damaged, improve the cleaning effect in the vicinity of the ink ejection holes, and prevent color mixture of ink during the cleaning.

Further, the image forming apparatus according to the present invention has a print head having an ink ejection surface provided with a row of ink ejection holes for ejecting a plurality of colors of ink for each color, and formed in a columnar shape with an elastic material. The cleaning member is formed such that the length of the cross-section perimeter thereof is longer than the distance between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes provided on the ink ejection surface of the print head. When,
And a moving unit that relatively rotationally moves the cleaning member in contact with the ink ejection surface of the print head, and rotationally moves in a state that the outer peripheral surface of the cleaning member is in contact with the ink ejection surface. An ink jet head adapted to suck ink in the ink ejection hole due to a pressure change in the ink ejection hole at the time of: a head for mounting and fixing the ink jet head at a predetermined position of the apparatus main body and releasing the fixation. Detachable mechanism;
It is equipped with.

With this structure, the ink jet head is formed into a columnar shape with a material having elasticity, and the length of the circumference of the cross section is in the column direction of the ink ejection holes provided on the ink ejection surface of the print head. The cleaning member, which is formed longer than the distance between the first row and the last row in the orthogonal direction, is relatively rotated while being in contact with the ink ejection surface of the print head, and the outer peripheral surface of the cleaning member is moved. The ink in the ink ejection hole is sucked and removed by the pressure change in the ink ejection hole when the ink is rotated while moving in contact with the ink ejection surface. As a result, it is possible to prevent the ink ejection surface of the print head from being damaged, improve the cleaning effect in the vicinity of the ink ejection holes, and prevent color mixture of ink during the cleaning.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an inkjet head 1 according to the present invention and the inkjet head 1.
FIG. 3 is a perspective view showing an embodiment of the printer body 2 on which the printer is mounted. FIG. 1 shows a type in which the inkjet head 1 has an independent form and is directly attached to the printer main body 2. Then, the inkjet 1 is housed as shown by an arrow H and set in the printer body 2 in a fixed state to form an image forming apparatus, for example, an inkjet printer.

The ink jet head 1 is for ejecting liquid ink into fine particles by, for example, an electrothermal conversion type or an electromechanical conversion type, and ejecting the ink dots onto a recording paper (recording medium). Also, as shown in FIG. 2, the ink cartridge 3, the print head 4, and the head cap 5 are provided.

The ink cartridge 3 contains ink of one color or a plurality of colors inside, and its housing is shown in FIG.
In the width direction of the printer main body 2 shown in FIG. 1, that is, in the width direction of the recording paper, it is elongated over the entire width. Although not shown in the drawing, there are, for example, four ink chambers inside the housing, which are filled with four color inks of yellow Y, magenta M, cyan C, and black K. The ink cartridge 3 is made of hard resin or the like.

On the bottom surface of the ink cartridge 3,
As shown in FIG. 2 (enlarged cross-sectional view of the inkjet head 1 shown in FIG. 1), a print head 4 is provided. The print head 4 is for finely atomizing the ink supplied from the ink cartridge 3 and ejecting the ink, and the ink ejecting holes formed of minute holes are formed in the entire width of the recording paper along the longitudinal direction of the ink cartridge 3. The ink ejection surface 6 is provided correspondingly.

The ink ejection surface 6 is formed into a thin sheet by nickel electroforming with a material containing nickel and nickel, for example, and extends in the longitudinal direction of the ink cartridge 3 to form yellow Y, magenta M, and cyan C. ，
Rows of ink ejection holes of four colors of black K are provided respectively, and the line head is an integrated type of four colors. Although illustration is omitted, Y, M, and
A portion having a row of ink ejection holes of each of C and K and a portion having a convex portion in which the head electrode is covered with resin on both sides sandwiching the ink ejection hole are formed in a wavy surface shape. .

On the bottom side of the ink cartridge 3,
A head cap 5 is attached. The head cap 5 serves as a cap member that covers the ink ejection surface 6 of the print head 4 and protects the ink ejection hole from drying and clogging, and has the same length as the housing of the ink cartridge 3. It is elongated and formed in a shallow box shape having an open upper surface, and is mounted so as to be rotatable relative to the print head 4 and detachable. The head cap 5 is moved by moving means such as a motor in a direction orthogonal to the longitudinal direction of the ink ejection surface 6 of the print head 4 as indicated by arrows A and B, and the ink is moved in the direction of arrow A. Removed from the cartridge 3,
The ink cartridge 3 is mounted again in the state of returning to the arrow B direction. The head cap 5 is made of hard resin or the like.

A cleaning roller 7 is provided inside the head cap 5. The cleaning roller 7 serves as a cleaning member for cleaning the ink ejection surface 6 of the print head 4, is formed of an elastic material in a cylindrical shape, and is formed on one side of the head cap 5. It is attached in the longitudinal direction of the head cap 5. Therefore, it is parallel to the longitudinal direction of the ink ejection surface 6 of the print head 4. And
The cleaning roller 7 rotates together with the head cap 5 in the arrow A direction to clean the ink ejection surface 6 of the print head 4. From this, the head cap 5 also serves as a moving unit that relatively rotationally moves the cleaning roller 7 in a state of being in contact with the ink ejection surface 6 of the print head 4.

Further, the cleaning roller 7 has a first row and a last row in the direction in which the peripheral length of the cross section is orthogonal to the row direction of the ink ejection holes provided on the ink ejection surface of the print head. It is formed longer than the interval.
That is, in FIG. 2, the row of the yellow Y ink ejection holes is the first row in the direction orthogonal to the row direction of the ink ejection holes provided on the ink ejection surface 6 of the ink cartridge 3, and the last row. Assuming that the distance between the black K ink ejection hole array is L and the cleaning roller 7 has a diameter of D, the peripheral length of the cleaning roller 7 is πD. Therefore, in this case, L ≦
The equation of πD holds, and D ≧ L / π. That is, the diameter D of the cleaning roller 7 is formed so as to satisfy D ≧ L / π. Note that FIG. 2 shows the case of D = L / 2π. As a result, it is possible to prevent the color mixture of inks because the outer peripheral surface of the cleaning roller 7 does not carry out the cleaning of the ink ejection holes of other colors once again at the contact portion where the ink ejection holes of the predetermined color have been cleaned. it can.

Similarly, an ink receiving portion 8 is provided inside the head cap 5. The ink receiving portion 8 receives the preliminary ejected ink from the ink ejection holes of the print head 4, and is adapted to receive the preliminarily ejected ink on a part or the whole of the bottom surface of the shallow box-shaped head cap 5. ing.

Next, specific examples of the head cap 5 and the cleaning roller 7 will be described with reference to FIGS. First, in FIG. 4, the head cap 5 is
It is formed in an elongated shape according to the width and length of the ink cartridge 3 shown in FIG. 1. As shown in FIG. 3, it is formed in a shallow box shape having a bottom surface at the bottom, a side wall standing all around, and an opening at the top. ing. Then, as described above, the head cap 5 is moved in the direction orthogonal to the longitudinal direction of the ink ejection surface 6 of the print head 4 as indicated by arrows A and B, but in the state of returning to the direction of arrow B, the ink cartridge is again returned. 3, the positioning claw 12 is provided on the upper end portion of the side wall opposite to the cleaning roller 7 as a positioning means when the positioning claw 12 is attached to the cleaning roller 7.
Is provided. The positioning claw 12 is engaged with the lower side edge of the ink cartridge 3 to position the head cap 5.

In the vicinity of one side wall in the longitudinal direction on the print head 4 side of the head cap 5, a cleaning roller formed in a cylindrical shape is in contact with the entire length of the ink ejection surface 6 of the print head 4. 7 is detachably held. That is, as shown in FIG. 4, pins 9 project from the both ends of the cleaning roller 7, and the pins 9 are held by holding members 10 that stand up in a substantially U-shape as shown in FIG. ing. The pin receiving portion on the upper part of the holding member 10 can be elastically opened and closed. When the pin 9 is pressed against the pin receiving portion from above, the pin receiving portion is opened and the pin 9 is opened.
Accept, then close and hold. On the contrary, by lifting the pin 9 upward, the pin receiving portion is opened so that the pin 9 can be removed.

As shown in FIGS. 4 and 5, the cylindrical shape of the cleaning roller 7 is a so-called crown shape in which the central portion in the longitudinal direction is gradually thickened. This is to prevent the cleaning roller 7 from flexing downward at the central portion in the longitudinal direction, and thus preventing the cleaning roller 7 from coming into non-contact with the ink ejection surface 6.

The portion of the cleaning roller 7 that comes into contact with the ink ejection surface 6 is made of elastic material such as rubber. That is, the core material of the cleaning roller 7 is formed of, for example, metal or hard resin, but the peripheral surface portion outside the core material is formed of an elastic member such as rubber. The cleaning roller 7
The whole may be formed of an elastic member such as rubber.

Then, as shown in FIG. 3, in the portion for holding the cleaning roller 7 on the head cap 5, as shown in FIG.
The floating spring 11 is interposed. The floating spring 11 serves as a means for urging the cleaning roller 7 toward the ink ejection surface 6 side of the print head 4, and is composed of, for example, a leaf spring formed in a substantially U shape in a side view, and the holding member. It is inserted below the pin 9 in the vicinity of 10. Then, the biasing force of the floating spring 11 acts on the pins 9 at both ends to press the cleaning roller 7 against the ink ejection surface 6 of the print head 4 with a substantially uniform force.

As a result, as shown in FIG. 2, with the head cap 5 attached to the bottom surface side of the ink cartridge 3, the biasing force of the floating spring 11, the elastic force of the cleaning roller 7, and the crown shape. The cleaning roller 7 is connected to the print head 4 by
It comes into contact over the entire length of the ink ejection surface 6. The floating spring 11 is substantially U-shaped.
The leaf spring is not limited to the character-shaped leaf spring, and may be a coil spring.

The cleaning roller 7 is driven to rotate by contact with the ink ejection surface 6 of the print head 4. Therefore, as shown in FIG. 2, when the head cap 5 moves in the direction of arrow A, the cleaning roller 7 rotates while closely contacting the entire length of the ink ejection surface 6 of the print head 4 with an appropriate pressure, and its rotational movement. Thus, the ink adhering to the ink ejection surface 6 is cleaned.

Now, the cleaning action of the cleaning roller 7 on the ink ejection surface 6 of the print head 4 and the head cleaning method will be described with reference to FIG. Note that in FIG. 6, the ink ejection surface 6, the ink ejection holes 13, and the cleaning roller 7 are shown in an enlarged sectional view for the sake of easy understanding. First, FIG.
2, the cleaning roller 7 moves in the arrow A direction together with the head cap 5 shown in FIG. 2, and is driven and rotated by the contact with the ink ejection surface 6 in the arrow C direction. Then, the cleaning roller 7 causes the ink ejection holes 13 of a certain row on the ink ejection surface 6 of the print head 4 shown in FIG.
Suppose you pass the position.

FIG. 6A shows the cleaning roller 7 moving in the direction of arrow A while being driven and rotated in the direction of arrow C.
Shows the state of approaching the position of the ink ejection hole 13 in a certain row. At this time, the ink ejection hole 13 is filled with the ink 15 from the ink chamber 14, and a concave curved meniscus 16 is formed inside the ink ejection hole 13 due to the interfacial tension of the surface of the ink 15. Has been formed. Then, as shown in FIG. 6A, the cleaning roller 7 is driven to rotate in the direction of arrow C while moving in the direction of arrow A, so that the ink ejection hole 13 is moved from one side edge to the other side edge. The air in the ink ejection hole 13 is pushed out through the gap on the other side edge portion as indicated by an arrow D during that time.

Next, as shown in FIG. 6B, when the cleaning roller 7 further moves in the direction of arrow C while being driven to rotate in the direction of arrow C, and just comes to the position of the ink discharge hole 13, The ink ejection holes 13 are completely closed. At this time, since the cleaning roller 7 is pressed against the ink ejection surface 6 and is in contact therewith, microscopically, a part of the surface of the cleaning roller 7 is elastic so that one side edge of the ink ejection hole 13 is formed. Part of the ink ejection hole 13 between the edge portion and the other side edge portion, and the air in the ink ejection hole 13 is pushed out by that amount to block the inlet of the ink ejection hole 13 and seal the inside. There is.

Thereafter, as shown in FIG. 6C, the cleaning roller 7 further moves in the direction of the arrow A while being driven by the direction of the arrow C to block the other edge portion of the ink ejection hole 13. Open one side edge only. At this time, microscopically, when a part of the surface of the cleaning roller 7 that slightly enters the ink ejection hole 13 separates from one side edge of the ink ejection hole 13, the inside of the ink ejection hole 13 is sealed. The air thus drawn is drawn and sucked through the gap at the one side edge as indicated by arrow E.

That is, as shown in FIG. 6B, the air in the ink discharge hole 13 is pushed out a little and sealed (positive pressure), and then the ink discharge hole 13 is discharged as shown in FIG. 6C. When the air inside is drawn out (negative pressure), the pressure change in the ink ejection hole 13 causes the ink in the ink ejection hole 13 to be sucked. As a result, the suction force that pulls the ink remaining in the ink discharge hole 13 to the outside of the print head 4 in FIG. 2 acts, and the ink in the ink discharge hole 13 can be sucked and reliably removed. .

In this case, since the cylindrical cleaning roller 7 made of an elastic material such as rubber is moved on the ink ejection surface 6, the head electrode of the ink ejection surface 6 is covered with resin. The ink ejection surface 6 can be cleaned without damaging the protective layer.

FIG. 7 is a side view showing another embodiment of the cleaning roller 7. In this embodiment, the cleaning roller 7 is provided with a large number of small holes 17,
It is a member in which 17, ... And
The inner diameter of the small hole 17 is set to such a size that the ink can be captured and held inside due to the capillary phenomenon. In this case, as described with reference to FIG. 6, the ink sucked and removed by the cleaning roller 7 and the ink wiped by the outer peripheral surface of the cleaning roller 7 are removed by a large number of inks formed on the outer peripheral surface of the cleaning roller 7. Small holes 17, 17,
Since it can be captured and held by the capillary phenomenon of ..., It is possible to perform clean cleaning without leaving ink on the ink ejection surface 6.

The cleaning roller 7 may be formed of an elastic sponge-like material into a columnar shape, and may be a member having a large number of small holes 17, 17, ... On its outer peripheral surface. In this case, since the ink that is captured and held by the capillary action of the large number of small holes 17, 17, ... Is absorbed by the sponge-like portion in the central portion, the ink that has been once cleaned is retained in the cleaning roller 7. Then, the next cleaning can be performed.

FIG. 8 is a side view showing the structure of the cleaning roller 7 according to another embodiment. This embodiment is
Partition plates 61a to partition the cylindrical elastic material from the rotation shaft 9 of the cleaning roller 7 toward the outer peripheral surface between the areas on the outer peripheral surface of the cleaning roller 7 that are in contact with the ink ejection holes of the adjacent colors. 61d is formed. With such a configuration, the cleaning roller 7 that sucks and removes the ink in the ejection holes 13 provided on the ink ejection surface 6 has its elastic member divided into four parts by the partition plates 61a to 61b. Each of the four sections is a section for cleaning the row of ink ejection holes for yellow Y, magenta M, cyan C, and black K. As a result, in the configuration shown in FIG. 7, the ink of each color captured and absorbed by the capillary action of the large number of small holes 17, 17, ... Formed on the outer peripheral surface of the cleaning roller 7 is stored in the cleaning roller 7. It is possible to prevent color mixing in the held state.

FIG. 9 is a side view showing the structure of the cleaning roller 7 according to still another embodiment. In this embodiment, a groove 62a having a predetermined depth from the outer peripheral surface of the cleaning roller 7 to the rotating shaft 9 is provided between the areas on the outer peripheral surface of the cleaning roller 7 which are in contact with the ink ejection holes of the adjacent colors. 62d is cut. As a result, as in the case of the embodiment shown in FIG. 8, it is divided into four parts, and is captured and absorbed by the capillary action of the numerous small holes 17, 17, ... Formed on the outer peripheral surface of the cleaning roller 7. It is possible to prevent the color inks from being mixed in a state of being held in the cleaning roller 7.

Next, a specific mechanism for the movement and driven rotation of the cleaning roller 7 shown in FIG. 2 will be described with reference to FIGS. 10 and 11. FIG. 10 is a side view showing details of the head cap opening / closing mechanism 20 shown in FIG. First, the cleaning roller 7 shown in FIG. 2 is attached to the head cap 5 as shown in FIG. 3, and the head cap 5 has a linear rack 22 formed on the lower side as shown in FIG. It is connected to and supported by the moving rack plate 40.

The moving rack plate 40 moves the head cap 5 in the directions of arrows A and B. Two guide pins 41a, which are provided at both upper ends of the inner side surface of the moving rack plate 40, are provided. 41b is engaged with the linear movement guide groove 43 formed in the one outer side plate 42 of the printer body 2 shown in FIG. 1 to form the rack 22 formed on the lower side.
Is engaged with and supported by the pinion 23 rotated by the worm gear 45 on the rotation shaft of the moving motor 44 attached to the one outer plate 42.

Two head guide pins 46a and 46b are provided on one outer surface of the head cap 5 so as to project toward the moving rack plate 40. Also, one outer plate 42 of the printer body 2
Two cap guide grooves 4 curved in a predetermined shape for forming a moving locus of the head cap 5 are formed in an intermediate portion of
7, 48 are formed. Then, two cap guide pins 46a, 46b are provided on the front and rear of the head cap 5.
Are respectively engaged with the cap guide grooves 47, 48 of the outer side plate 42 of the printer body 2, and only the front cap guide pin 46a is formed in a vertically long guide groove at the front end of the moving rack plate 40. 49 is engaged.

With such a mechanism, the pinion 2 is driven by the driving motor 44 through the worm gear 45.
3 rotates in the directions of arrows F and G, and the rack 2 meshes with it.
2, the moving rack plate 40 moves in the directions of arrows A and B. At this time, since the cap guide pin 46a at the front portion of the head cap 5 is engaged with the guide groove 49 at the front end portion of the moving rack plate 40, the head cap 5
Moves in the directions of arrows A and B together with the moving rack plate 40. The movement trajectory of the head cap 5 at that time is determined by the shapes of the cap guide grooves 47 and 48 with which the two front and rear cap guide pins 46a and 46b engage.

FIG. 11 is an enlarged side view of the main part of FIG. 10, showing a specific structure of the driven rotation of the cleaning roller 7. That is, inside the head cap 5,
A spring support member 50 is erected inside a holding member 10 that holds the pins 9 at both ends of the cleaning roller 7, and a coil spring 51 is wound around the spring support member 50 and mounted. ,
The pin 9 of the cleaning roller 7 is pressed against the lower surface of the bearing 52 that rotatably supports the pin 9.

Therefore, the cleaning roller 7 can be constantly urged upward by the elastic force of the coil spring 51 and pressed against the ink ejection surface 6 of the print head 4. As a result, when the head cap 5 moves in the direction of arrow A in FIG.
The cleaning roller 7 pressed against is driven to rotate in the direction of arrow C due to the pressure contact with the ink ejection surface 6.

FIG. 12 is an enlarged side view of essential parts showing another embodiment of the moving mechanism of the cleaning roller 7. This embodiment is provided with a rotation moving mechanism for bringing a predetermined contact portion on the outer peripheral surface of the cleaning roller 7 into contact with a row of predetermined ink ejection holes formed on the ink ejection surface 6, and the cleaning roller 7 is provided. The rotational movement mechanism allows the outer peripheral surface of the cleaning roller 7 and the corresponding portion of the ink ejection surface 6 of the print head 4 to make one-to-one contact and rotationally move. As shown in FIG. 12, the rotational movement mechanism includes a pinion gear 63 integrally fixed to the pin 9 of the cleaning roller 7.
And a rack 64 provided at the end of the print head 4 so as to mesh with the pinion gear 63.

As a result, the moving motor 4 shown in FIG.
4 drives the pinion 23 to rotate in the direction of arrow F, and the rack 22 meshing with the pinion 23 moves the rack plate 4 for movement.
When 0 moves in the direction of arrow A, the pinion gear 63 fixed to the pin 9 of the cleaning roller 7 rotates in the direction of arrow C, and the pinion gear 63 and the rack 64 provided on the print head 4 are separated from each other. By engaging with each other, the corresponding portions of the outer peripheral surface of the cleaning roller 7 and the ink ejection surface 6 of the print head 4 are relatively rotated while being in one-to-one contact with each other.

In this case, the cross-sectional length πD of the cleaning roller 7 is orthogonal to the column direction of the ink ejection holes 13 provided on the ink ejection surface 6 of the print head 4, as shown in FIG. Since the gap between the first row and the last row in the direction is formed to be longer than that of the first row, the ink ejection holes of other colors should be cleaned again at the contact portion where the ink ejection holes of the predetermined color have been cleaned once. Therefore, it is possible to prevent the color mixture of the cleaning roller 7. The rotational movement mechanism is not limited to the structure shown in FIG. 12, and the corresponding portions of the outer peripheral surface of the cleaning roller 7 and the ink ejection surface 6 of the print head 4 can be brought into one-to-one contact and rotationally moved. Any other structure may be used as long as it is one.

Next, a series of cleaning operations by the cleaning roller 7 of the ink jet head 1 configured as described above will be described with reference to FIG. Here, in the inkjet head 1 shown in FIG.
It is assumed that the head cap 5 moves in the direction of arrow A, the ink ejection surface 6 of the print head 4 is cleaned, and after that, preliminary ink ejection is performed. First, FIG.
(A) shows an initial state in which the head cap 5 is closed with respect to the ink cartridge 3. Then, in this state, in FIG. 1, the inkjet head 1 is housed and set in the printer body 2.

Next, when the head cap 5 is set in the printer main body 2 and the head cap open signal is received, the head cap 5 is moved to the ink cartridge 3 as shown in FIG. 13B.
It is moved in the direction of arrow A relative to. Then, the cleaning roller 7 moves together with the head cap 5 in the direction of arrow A with respect to the ink cartridge 3, and cleans the ink ejection surface 6 in a state of pressingly contacting the ink ejection surface 6 of the print head 4. At this time, the cleaning roller 7 is driven to rotate while being in contact with the ink ejection surface 6, or its rotation is restricted by a brake mechanism or a fixing mechanism, or is rotated in a forward direction or a reverse direction by a rotation drive mechanism to move. .

In this state, in FIG. 2, for example, among the ink ejection surfaces 6 of the print head 4, the ink ejection surface 6 of yellow Y is cleaned. Then, the position detecting means (not shown) provided on the lower surface side of the head cap 5 detects that the cleaning of the ink ejection surface 6 of yellow Y has been completed. As a result, a preliminary ejection start signal is sent to the ink ejection holes on the yellow Y ink ejection surface 6.

Next, as shown in FIG. 13C, the preliminary ejection ink 18 is ejected from the ink ejection hole of the yellow Y ink ejection surface 6. After that, the preliminary ejection end signal is sent to the ink ejection holes of the yellow Y ink ejection surface 6, and the ejection of the preliminary ejection ink 18 is stopped. Thereafter, in the same manner, in FIG. 2, each time the cleaning of the ink ejection surface 6 of M, C, and K is completed by the cleaning roller 7, the completion of cleaning of the ink ejection surface 6 is detected by the position detection means, and the respective inks are detected. A preliminary discharge start signal and a preliminary discharge end signal are sent to the discharge holes. As a result, the timing of preliminary ejection from each ink ejection hole is controlled, and the preliminary ejection of ink is sequentially executed.

When the cleaning and preliminary ejection of the ink ejection surfaces 6 of the respective colors are completed in this way, the head cap 5 moves fully in the direction of arrow A and moves slightly upward, as shown in FIG. 13 (d). Fits in the retracted position. In this state, printing and printing are performed on the recording paper.

Next, when printing and printing of the required number of pages are completed, a head cap close signal is sent and the head cap 5
From the retracted position, as shown in FIG.
It is moved in the direction of arrow B relative to the ink cartridge 3. Then, the cleaning roller 7 along with the head cap 5 is attached to the ink cartridge 3 by the arrow B.
The cleaning roller 7 on the return path.
Returns without contacting the ink ejection surface 6 of the print head 4.

Then, as shown in FIG. 13 (f), the head cap 5 is fully moved in the direction of arrow B with respect to the ink cartridge 3 to be in the closed state, and the initial state is restored. Then, it waits for the next print or print instruction.

In the above operation, the ink is preliminarily ejected after the cleaning of the ink ejection surface 6 of the print head 4, but the ink is ejected before the cleaning of the ink ejection surface 6 by the cleaning roller 7. The preliminary discharge may be performed. In this case, it is not necessary to control the timing of preliminary ejection from the Y, M, C, and K ink ejection holes by the position detecting means.

Next, an image forming apparatus, such as an inkjet printer, as a related invention of the inkjet head 1 will be described with reference to FIGS. 1 and 14 to 20. In this inkjet printer, ink is finely atomized and ejected from an inkjet head, and ink dots are sprayed on a recording paper to print. As shown in FIG. 1, the inkjet head 1 and a printer main body 2 are used.
A head attaching / detaching mechanism 19 and a head cap opening / closing mechanism 2
0 and. The inkjet printer is of a type in which the inkjet head 1 is directly attached to the printer body 2.

The ink jet head 1 is for ejecting liquid ink into fine particles by, for example, an electrothermal conversion method or an electromechanical conversion method, and ejecting the ink dots on a recording paper. The configuration is the same as that described in.

The printer main body 2 is for mounting the ink jet head 1 at a predetermined position and exerting the function as an ink jet printer, and includes a recording paper tray, a recording paper transport system, an operation drive system, and an overall control circuit. It has a department. Note that, in FIG. 1, reference numeral 21 indicates a paper discharge tray that is discharged after printing.

The head attaching / detaching mechanism 19 is for mounting and fixing the ink jet head 1 at a predetermined position of the printer main body 2 and releasing the fixation, and is composed of, for example, a recess provided in the central portion of the printer main body 2. It is composed of a horizontally long bar member configured to insert the inkjet head 1 into a predetermined position and press the upper surface thereof. That is,
The printer body 2 extends in the entire width direction and is tilted, for example, in the vertical direction and the horizontal direction. Then, as shown in FIG. 1, the inkjet head 1 is housed and mounted in the direction of arrow H with the bar member standing vertically.
As shown in FIG. 14, the inkjet head 1 is fixed to the predetermined position in a state in which the bar member is tilted in the horizontal direction.

The head cap opening / closing mechanism 20 moves the head cap 5 relative to the print head 4 (see FIG. 2) in a state where the ink jet head 1 is fixed at a predetermined position of the printer body 2 and the ink ejection surface. 6 (Fig. 2
(Refer to FIG. 4) and closes the head cap 5 after printing is completed. For example, the rack 22 provided on the side surface of the printer body 2 and the pinion 23 are engaged with each other. The detailed structure is as described above with reference to FIG.

Then, as shown in FIG. 14, with the ink jet head 1 fixed to a predetermined position of the printer body 2 by the head attaching / detaching mechanism 19, the pinion 23 is moved to the position shown in FIG.
By rotating in a predetermined direction by the moving motor 44 shown in FIG. 15, the rack 22 moves in the direction of arrow A as shown in FIG. 15, and the head cap 5 shown in FIG. It is designed to fit in the retracted position.

The head cap opening / closing mechanism 20 described above is used.
Is not limited to the above-mentioned engagement between the rack 22 and the pinion 23. For example, a rubber roller is pressed against both side surfaces of the head cap 5, a motor is coupled to the rotation shaft of the rubber roller, and the motor is rotated to rotate the rubber roller. The head cap 5 may be moved in the direction of arrow A and opened by friction.

Next, the ink jet head 1 is fixed to a predetermined portion of the printer body 2 shown in FIG. 1, the head cap 5 is moved relative to the print head 4 (see FIG. 2), and the ink ejection surface 6 (see FIG. The specific mechanism and operation for releasing (see 2) will be described with reference to FIGS. 16 to 20.

First, FIG. 16 shows a state in which the ink jet head 1 in FIG. 1 is inserted and stored in a predetermined position of the printer body 2 in the direction of arrow H. In this state, the lower end portions of the cap lock hooks 24 provided at both end portions of the inkjet head 1 are engaged with the locking piece portions 26 on both side portions of the head cap 5 by the elastic force of the spiral spring 25. ing. As a result, the head cap 5 is integrally attached to the ink cartridge 3.

In this state, in FIG. 16, the head attaching / detaching mechanism 19 is pushed down in the direction of arrow J and fixed. Then,
The cap lock releasing piece 27 provided on the lower side of the head attaching / detaching mechanism 19 pushes down and rotates the upper end 28 of the cap lock hook 24, and lifts the lower end of the cap lock hook 24 as shown in FIG. , The engagement with the locking pieces 26 on both sides of the head cap 5 is released.
As a result, as shown in FIG. 14, the inkjet head 1 is fixed to a predetermined position of the printer body 2 by the head attaching / detaching mechanism 19, and the head cap 5 is movable.

Next, the head cap opening / closing mechanism 20 shown in FIG. 14 is operated, and the pinion 23 is rotated by the moving motor 44 shown in FIG. 10 to move the rack 22 in the direction of arrow A. Then, as shown in FIG. 18, the head cap 5 mounted on the bottom surface side of the ink cartridge 3 moves in the arrow A direction together with the rack 22 and opens. Then, as shown in FIG. 2, cleaning of the ink ejection surface 6 of the print head 4 provided on the bottom surface of the ink cartridge 3 is started by the cleaning roller 7 biased by the floating spring 11. In addition, in FIG. 18, the symbol P indicates the locus of movement of the head cap 5.

After that, the head cap 5 is removed as shown in FIG.
As shown in, the movement is sequentially made in the direction of arrow A according to the movement locus P. At this time, by the cleaning roller 7 attached to the head cap 5, Y, M, and
The ink ejection surfaces 6 of C and K colors are sequentially cleaned, and preliminary ejection of ink is performed before or after the cleaning.

When the cleaning of the ink ejection surface 6 of each color and the preliminary ejection are completed, the head cap 5 moves in the direction of the arrow A as shown in FIG. As shown in FIG. 15, it fits in the retracted position. In this state, printing and printing are performed on the recording paper. At this time, since the head cap 5 moves slightly upward as shown in FIG. 20, the space for storing the head cap 5 can be reduced. Further, in FIG. 20, the recording paper passes under the print head 4 provided on the bottom surface of the ink cartridge 3, but the lower surface of the head cap 5 may guide the passage of the recording paper. In this case, a rib for guiding the recording paper may be provided on the lower surface side of the head cap 5. Further, water repellent treatment may be performed so that the ink in the printed state does not adhere to the recording paper.

In this state, when printing and printing of the required number of pages are completed, the head cap 5 moves in the direction of arrow B from the retracted position shown in FIG.
As shown in FIG. 7, the head cap 5 returns to the bottom surface side of the ink cartridge 3 to be in the initial state.

Then, in FIG. 16, by opening the head attaching / detaching mechanism 19 in the direction opposite to the arrow J, the cap lock hook 24 is attached to the engaging piece portions 26 on both sides of the head cap 5 by the elastic force of the spiral spring 25. The head cap 5 is engaged and the ink cartridge 3 is integrally mounted. In this state, as shown in FIG. 1, the inkjet head 1 can be removed from the printer body 2.

If the power of the printer is cut off for some reason while the head cap 5 is in the retracted position shown in FIG. 20, the head cap 5 remains in the retracted position. Become. Then, in this state, if the head attaching / detaching mechanism 19 is opened in the direction opposite to the arrow J as shown in FIG. 16, only the ink cartridge 3 will be removed while the head cap 5 is left in the retracted position. . Therefore, in order to prevent this, when the power of the printer is cut off for some reason, the head cap 5 at the retracted position is automatically returned to the initial position shown in FIG. The cap 5 is shown in FIG.
An interlock mechanism may be provided so that the head attaching / detaching mechanism 19 cannot be opened in the direction opposite to the arrow J when the head has not returned to the initial position shown in FIG.

The ink jet printer described with reference to FIG. 1 and FIGS. 14 to 20 is of the type in which the ink jet head 1 is directly attached to the printer body 2.
The present invention is not limited to this, and is similarly applicable to other types in which the inkjet head 1 is mounted on the printer body 2 via the tray. An outline of another type of inkjet printer will be described below with reference to FIG.

First, as shown in FIG. 21A, the ink jet head 1 in which the head cap 5 is integrally attached to the ink cartridge 3 is installed inside the tray 29 provided so as to advance and retreat with respect to the printer body 2. Attach it in the prescribed position as shown by arrow Q. Then, move the tray 29 to the arrow R
It is moved in the direction and set in the printer body 2. At this time, as shown in FIG. 21B, the head cap 5 is stopped by being stopped by an appropriate hooking means provided in the printer body 2 during the movement of the tray 29 in the arrow R direction. . The tray 29 is used to set or replace the inkjet head 1 in the printer body 2.

Thereafter, the tray 29 is moved in the direction of arrow R as it is, whereby the ink cartridge 3 is moved in the direction of arrow R relative to the head cap 5,
As a result, the head cap 5 opens. At the same time, when the head cap 5 moves relative to the ink cartridge 3 in the direction of the arrow R, the ink ejection surface 6 of the print head 4 is cleaned by the same operation as that shown in FIG. Preliminary discharge is performed.
After that, printing and printing are performed on the recording paper. In FIG. 21, reference numeral 30 indicates a recording paper tray, and reference numeral 3
Reference numeral 1 denotes a recording sheet, reference numeral 32 denotes a feed roller, reference numeral 33 denotes a feed belt, reference numeral 34 denotes a paper discharge tray, and reference numeral S denotes a recording paper discharge direction.

In the above description, the line head type ink jet printer has been described, but the present invention is not limited to this, and can be applied to a serial type ink jet printer. Further, although an example of an inkjet printer has been described in the above description, the present invention is not limited to this, and can be applied to an image forming apparatus such as a facsimile apparatus or a copying machine whose recording method is an inkjet method.

[0078]

Since the present invention is constructed as described above,
According to the ink jet head of the first aspect, the eighth aspect, and the ninth aspect of the present invention, the ink jet hole is formed of an elastic material in a columnar shape, and the length of the circumference of the cross section of the ink jet hole provided on the ink jet surface of the print head is large. The cleaning member, which is formed longer than the distance between the first row and the last row in the direction orthogonal to the row direction, is relatively rotated while being in contact with the ink ejection surface of the print head. The ink in the ink ejection holes can be sucked and removed by the pressure change in the ink ejection holes when the outer peripheral surface of the ink is rotationally moved while being in contact with the ink ejection surface. As a result, it is possible to improve the cleaning effect in the vicinity of the ink ejection holes without damaging the ink ejection surface of the print head, and to reapply another color at the contact portion where the ink ejection holes of a predetermined color have been cleaned once. It is possible to prevent ink from being mixed on the outer peripheral surface of the cleaning member without cleaning the ink ejection holes. Further, unlike the conventional method, since the suction pump is not used to suck a little more ink in the ink discharge hole,
It is possible to prevent wasteful consumption of ink.

According to the second aspect of the present invention, since the cleaning member has a large number of small holes formed on the outer peripheral surface thereof, the outer peripheral surface of the cleaning member serves as the ink ejection surface of the print head. Ink that has been sucked from the ink ejection holes due to the pressure change in the ink ejection holes when rotating while being in contact is trapped in the small holes by the capillary action of the numerous small holes on the outer peripheral surface, and the ink is ejected. It can be reliably removed and cleaned without being left on the surface.

Further, according to the third aspect of the invention, the cleaning member has the outer peripheral surface side from the rotation axis of the cleaning member between the regions on the outer peripheral surface in contact with the ink ejection holes of the adjacent colors. By forming a partition plate for partitioning the material having elasticity, it is possible to prevent the ink of each color captured and absorbed by the cleaning roller from being mixed in a state of being held in the cleaning roller. You can

According to a fourth aspect of the present invention, the cleaning member has a rotation shaft side from the outer peripheral surface of the cleaning member between the regions on the outer peripheral surface which are in contact with ink ejection holes of adjacent colors. Since the groove having a predetermined depth is cut into the elastic material, the inks of the respective colors captured and absorbed by the cleaning roller are mixed while being held in the cleaning roller. Can be prevented.

Further, according to the invention of claim 5, since the cleaning member is formed in a crown shape in which the central portion is gradually thickened, the cleaning member is lowered at the central portion in the longitudinal direction. It is possible to prevent it from coming into non-contact with the ink ejection surface even when it is bent.

Further, according to the invention of claim 6, the cleaning member moves on the ink ejection surface while being rotated while being driven while being in contact with the ink ejection surface. It is possible to improve the cleaning effect in the vicinity of the ink ejection holes without damaging the ink ejection surface.

According to the seventh aspect of the present invention, the rotational movement is such that a predetermined contact portion on the outer peripheral surface of the cleaning member is brought into contact with a row of predetermined ink ejection holes formed on the ink ejection surface. The cleaning member is provided with a mechanism, and the rotating movement mechanism causes the outer peripheral surface of the cleaning member and the corresponding ink discharge surface of the print head to make contact with each other in a one-to-one manner and rotate. It is possible to prevent the ink ejection holes of other colors from being cleaned again at the contact portion where the ink ejection holes of a predetermined color have been cleaned, and it is possible to prevent ink color mixing on the outer peripheral surface of the cleaning member.

Further, according to the head cleaning method of the tenth, eleventh, and twelfth aspects, the material is formed into a columnar shape with an elastic material, and the peripheral length of the cross section is provided on the ink ejection surface of the print head. The outer peripheral surface of the cleaning member, which is formed longer than the distance between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes, is in one-to-one correspondence with the corresponding portion of the ink ejection surface of the print head. The ink in the ink ejection holes can be sucked and removed by the pressure change in the ink ejection holes when the ink is relatively rotated in the contact state. As a result, it is possible to prevent the ink ejection surface of the print head from being damaged, improve the cleaning effect in the vicinity of the ink ejection holes, and prevent color mixture of ink during the cleaning.

According to the image forming apparatus of the thirteenth, fourteenth and fifteenth aspects, the ink jet head is formed of a material having elasticity in a cylindrical shape, and the length of the cross section is the ink ejection surface of the print head. The cleaning member formed longer than the interval between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes provided in the one-to-one correspondence with the corresponding portion of the ink ejection surface of the print head. When the outer peripheral surface of the cleaning member is rotationally moved in contact with the ink ejection surface, the pressure change in the ink ejection hole causes the ink in the ink ejection hole to move relatively. Can be removed by suction. As a result, it is possible to prevent the ink ejection surface of the print head from being damaged, improve the cleaning effect in the vicinity of the ink ejection holes, and prevent color mixture of ink during the cleaning. Further, unlike the conventional case, the suction pump is not used to suck a little more ink in the ink ejection hole, so that wasteful consumption of ink can be prevented.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an inkjet head and a printer main body to which the inkjet head is attached according to the present invention.

FIG. 2 is an enlarged cross-sectional view of the inkjet head shown in FIG.

FIG. 3 is a side view showing a specific example of the head cap and the cleaning roller shown in FIG.

FIG. 4 is a plan view showing a specific example of the head cap and the cleaning roller.

5 is a cross-sectional view taken along line EE of FIG.

FIG. 6 is an enlarged cross-sectional view for explaining a cleaning action of an ink ejection surface of a print head by the cleaning roller and a head cleaning method.

FIG. 7 is a side view showing another embodiment of the cleaning roller.

FIG. 8 is a side view showing a state in which a partition plate for preventing color mixture is formed on the cleaning roller.

FIG. 9 is a side view showing a state in which a groove for preventing color mixture is formed on the cleaning roller.

10 is a side view for explaining the specific mechanism of the rotational movement of the cleaning roller shown in FIG. 2 and showing the details of the head cap opening / closing mechanism shown in FIG.

11 is an enlarged side view of the main part of FIG. 10, showing a specific structure of driven rotation of the cleaning roller.

FIG. 12 is an enlarged side view of essential parts showing an embodiment of the rotation moving mechanism of the cleaning roller.

FIG. 13 is an explanatory diagram showing a cleaning operation by a head cap and a cleaning roller of the inkjet head.

FIG. 14 is a perspective view showing an embodiment of an inkjet printer as an example of an image forming apparatus according to the present invention, and is a view showing a state in which an inkjet head is mounted.

FIG. 15 is a perspective view showing an embodiment of an inkjet printer, showing a state in which a head cap is opened.

16 is an explanatory diagram showing a specific mechanism and operation in which the inkjet head in FIG. 1 is inserted and housed in a predetermined position of the printer main body in a direction of an arrow H. FIG.

FIG. 17 is an explanatory diagram showing a specific mechanism and operation in which the inkjet head is fixed to a predetermined position of the printer main body by a head attaching / detaching mechanism and the head cap is movable.

FIG. 18 is an explanatory diagram showing a specific mechanism and operation in a state in which the head cap mounted on the bottom surface side of the ink cartridge moves in the direction of arrow A and is opened.

FIG. 19 is an explanatory diagram showing a specific mechanism and operation in a state where the head cap sequentially moves in the direction of arrow A according to the movement locus P.

FIG. 20 is an explanatory diagram showing a specific mechanism and operation in a state where the head cap has fully moved in the direction of arrow A according to the movement track P and is in the retracted position.

FIG. 21 is a schematic explanatory diagram showing another type of inkjet printer in which the inkjet head is mounted on the printer body via the tray.

[Explanation of symbols]

1 ... Inkjet head 2 ... Printer body 3 ... Ink cartridge 4 ... Print head 5 ... Head cap 6 ... Ink ejection surface 7 ... Cleaning roller 9 ... Cleaning roller pin 10 ... Holding member 11 ... Floating spring 13 ... Ink ejection hole 14 ... Ink chamber 15 ... Ink 17 ... Small hole 19 ... Head attachment / detachment mechanism 20 ... Head cap opening / closing mechanism 22 ... Rack 23 ... Pinion 40 ... Rack plate for movement 44 ... Moving motor 45 ... Worm gear 61 ... Partition board 62 ... groove 63 ... Pinion gear 64 ... Partition board

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masato Ando             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Hiroshi Tokunaga             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Shinichi Horii             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F-term (reference) 2C056 EA12 EA16 EC22 EC23 EC24                       EC54 FA03 FA04 FA13 JA03                       JB03 JB08 JC23

Claims (15)

[Claims] 1. A printhead having an ink ejection surface provided with a row of ink ejection holes for ejecting a plurality of colors of ink for each color, and ink for forming an image on a recording medium from the ink ejection holes. An inkjet head for ejection, which is formed in a columnar shape with an elastic material and whose cross-sectional perimeter is first in a direction orthogonal to the column direction of the ink ejection holes provided on the ink ejection surface of the print head. A cleaning member formed to be longer than the distance between the last row and the last row, and a moving means for relatively rotating the cleaning member in contact with the ink ejection surface of the print head. The ink inside the ink ejection holes is absorbed by the pressure change inside the ink ejection holes when the outer peripheral surface of the cleaning member rotates while moving in contact with the ink ejection surface. Ink jet head is characterized in that. 2. The ink jet head according to claim 1, wherein the cleaning member has a large number of small holes formed on the outer peripheral surface thereof. 3. The partition plate for partitioning the material having the elasticity from the rotation axis of the cleaning member to the outer peripheral surface side between the areas of the cleaning member contacting the ink ejection holes of the adjacent colors on the outer peripheral surface thereof. The inkjet head according to claim 1, wherein the inkjet head is formed. 4. The cleaning member has a predetermined depth in the material having elasticity from the outer peripheral surface of the cleaning member to the rotating shaft side between the areas on the outer peripheral surface of the cleaning member which are in contact with ink ejection holes of adjacent colors. The inkjet head according to claim 1 or 2, wherein the groove of the groove is cut. 5. The ink jet head according to claim 1 or 2, wherein the cleaning member is formed in a crown shape in which a central portion thereof is gradually thickened. 6. The ink jet head according to claim 1, wherein the cleaning member moves on the ink ejection surface while being driven to rotate while being in contact with the ink ejection surface. 7. A rotation moving mechanism for bringing a predetermined contact portion on the outer peripheral surface of the cleaning member into contact with a row of predetermined ink ejection holes formed on the ink ejection surface, the cleaning member comprising: The inkjet head according to claim 1 or 2, wherein a corresponding portion of the outer peripheral surface of the cleaning member and an ink ejection surface of the print head are brought into contact with each other in a one-to-one manner and rotationally moved by the rotational movement mechanism. 8. The moving means relatively moves the cleaning member in a direction orthogonal to a longitudinal direction of an ink ejection surface of the print head.
The described inkjet head. 9. The ink jet head according to claim 1, further comprising a cap member for protecting an ink ejection surface of the print head, wherein the cleaning member moves together with the cap member. 10. A head cleaning method for a print head having an ink ejection surface provided with a row of ink ejection holes for ejecting a plurality of colors of ink for each color, which is formed into a columnar shape with an elastic material, The outer circumference of the cleaning member whose peripheral length is longer than the distance between the first row and the last row in the direction orthogonal to the row direction of the ink ejection holes provided on the ink ejection surface of the print head. The surface of the cleaning member is rotated relative to the ink ejection surface of the print head, and when the outer peripheral surface of the cleaning member moves in contact with the ink ejection surface, the pressure in the ink ejection hole changes. A head cleaning method comprising sucking ink in the ink ejection holes. 11. The cleaning member has a large number of small holes formed on its outer peripheral surface.
0 head cleaning method. 12. The cleaning member according to claim 10, wherein the outer peripheral surface of the cleaning member and a corresponding portion of the ink ejection surface of the print head are brought into contact with each other in a one-to-one manner to rotate and move. Head cleaning method. 13. An ink ejection hole for ejecting a plurality of colors of ink for each color in an image forming apparatus for ejecting ink by atomizing the ink from an ink jet head and spraying ink dots on a recording medium. And a print head having an ink discharge surface provided with a row, and a columnar shape formed of an elastic material, the length of the cross section being the row direction of the ink discharge holes provided on the ink discharge surface of the print head. A cleaning member formed longer than the distance between the first row and the last row in a direction orthogonal to the direction, and relatively rotated while the cleaning member is in contact with the ink ejection surface of the print head. And a moving means for changing the pressure in the ink ejection hole when the outer peripheral surface of the cleaning member is rotationally moved while being in contact with the ink ejection surface. An inkjet head adapted to suck the ink in the ink discharge holes; and a head attaching / detaching mechanism for fixing and fixing the inkjet head at a predetermined position of the apparatus main body. A characteristic image forming apparatus. 14. The image forming apparatus according to claim 13, wherein the cleaning member of the ink jet head has a large number of small holes formed on the outer peripheral surface thereof. 15. A rotation moving mechanism for bringing a predetermined contact portion on the outer peripheral surface of the cleaning member into contact with a row of predetermined ink ejection holes formed on the ink ejection surface, the cleaning member comprising: 15. The image forming apparatus according to claim 13, wherein the rotational movement mechanism rotationally moves the outer peripheral surface of the cleaning member and the corresponding ink ejection surface of the print head in one-to-one contact with each other.