JP3339793B2 - Inkjet head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head which forms an image on a recording medium by ejecting ink, and more particularly, to a plate member provided with nozzles and a head body which are bonded with an adhesive. It relates to an inkjet head.

[0002]

2. Description of the Related Art Heretofore, as this type of ink jet head, a plate member provided with nozzles for ejecting ink, and a head body provided behind the plate member and ejecting ink through the nozzles And a plate member is known in which the plate member is bonded to an end surface of the head main body with an adhesive. The ink jet head configured as described above has a simple configuration and is easy to manufacture, and is extremely industrially advantageous.

[0003]

Conventionally, however, the area and shape of the end face of the head main body and the plate member are made the same, and bonding with an adhesive is performed. For this reason, the adhesive may protrude around the bonding portion, and in some cases, the protruding adhesive may flow around the nozzle surface (the surface facing the recording medium) of the plate member. In this case, the adhesive flowing around the nozzle surface may hinder the ejection of the ink. Then, not only can an accurate image not be formed, but also nozzle clogging may occur during wiping with a wiper or the like (hereinafter referred to as wiping).

Accordingly, an object of the present invention is to prevent an adhesive from flowing around a nozzle surface of a head in an ink jet head in which a plate member and a head body are bonded with an adhesive.

[0005]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the invention according to claim 1 provides a nozzle surface provided with a nozzle for ejecting ink and a nozzle surface thereof.
A plate member having an end surface located on the opposite side , and a head body provided behind the plate member and ejecting ink through the nozzles;
The end face of the meet ink jet head formed by glued to the end face of the head body, an end of the plate member
The area of the surface and greater than the area of the end face of the head body, the head body a peripheral portion of the end surface of the plate member
Along with protruded around the end surface, the protruding amount of the peripheral portion is less than 3 to 4 times the thickness of the plate member, the contact
Adhesive wraps around the nozzle surface from the end surface of the plate member
This is prevented by the protrusion of the peripheral edge .

In the present invention having the above-described structure, the area of the end surface of the plate member is made larger than the area of the end surface of the head body, and the peripheral edge of the end surface of the plate member is formed around the end surface of the head body. Projecting. For this reason, even if the adhesive protrudes from the bonding portion between the plate member and the head main body, the adhesive is disposed behind the plate member, that is, on the surface not facing the recording medium. Therefore, the adhesive is prevented from flowing around the nozzle surface of the head.

If the projection amount is more than four times the thickness, the plate member may be deformed when an external force is applied to the plate member, and an accurate image may not be formed. In the present invention, since the protrusion amount is set to 3 to 4 times or less of the thickness, it is possible to prevent the adhesive from sneaking around the nozzle surface satisfactorily and prevent the nozzle from being clogged. An extremely accurate image can be formed on a recording medium.

According to a second aspect of the present invention, there is provided an ink jet printer having a cap member for covering the nozzle in an airtight manner to prevent the ink in the nozzle from drying or sucking the ink in the nozzle. 2. The ink jet head according to claim 1, wherein a peripheral portion of the cap member contacts a nozzle surface of the plate member.

[0009] The power of the peripheral portion of the plate member of the cap member
Is brought into contact with the nozzle surface coated with Bruno nozzle airtight, when the anti-drying or suction of the ink in the ink, it is possible to form an accurate image in good prevent clogging of the nozzle.
However, in this case, a pressing force is applied to the nozzle surface from the peripheral portion of the cap member. However, in the present invention, since the amount of protrusion of the plate member is set to four times or less of the thickness, deformation of the plate member is prevented as described above even when a pressing force is applied, so that an accurate image is formed. Can be.
Therefore, according to the present invention, in addition to the effects of the first aspect of the present invention, there is an effect that the clogging of the nozzles can be more favorably prevented and a more accurate image can be formed on the recording medium.

[0010] According to a third aspect of the present invention, a nozzle is provided at a position opposite to a nozzle surface on which a nozzle for ejecting ink is provided.
A plate member having an end face which is provided behind the plate member, comprising: a head body which ejects ink through the nozzle, and a casing having an opening exposing the plate member, the plate member With the end face
The end face of the head body is met inkjet head that consists are bonded, the area of the end face of the plate member is larger than the area of the end face of the head body, the peripheral portion of the end surface of the plate member is the head Glued to the end face of the head body so as to protrude around the end face of the body,
A sealing material is filled between the inside of the opening of the casing and the head body on the head body side with respect to the plate member . Thereby, it is possible to prevent the ink from entering the casing. Claim
In the invention described in Item 4, a nozzle for ejecting ink is provided.
Plate part made of polyimide resin
Material, provided behind the plate member, the nozzle
A head body that ejects ink through the
The end face of the rate member is connected to the end face of the head body with an adhesive.
An ink jet head,
The area of the end surface of the head member from the area of the end surface of the head body.
Enlarge the edge of the end surface of the plate member
Protruding around the end face of the pad body, and
The protrusion amount of the plate member is 10 μm or more and the thickness of the plate member is
3 to 4 times or less, and the adhesive is the plate member.
It is said that the wrap around the nozzle face opposite to the end face
It is characterized by being prevented by protrusion. This allows
Effectively prevent the adhesive from flowing around the nozzle surface
Can be.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a schematic perspective view illustrating a configuration of the inkjet printer 1 to which the present invention is applied. FIG.
As shown in FIG.
Inside, a platen 4 is rotatably mounted, and an ink jet head 8 is mounted on a carriage 6 which moves in parallel with the axis of the platen 4. Then, a color image is printed on the recording paper 99 by ejecting a plurality of colors of ink from the inkjet head 8 on the recording paper 99 conveyed on the platen 4 as follows.

The ink-jet head 8 has ink cartridges 10y, 10m, 10m filled with yellow, magenta, cyan, or black ink.
The nozzles 12c, 10b and 12b are provided on the front surface (the surface facing the recording paper 99), as shown in FIG. 3 (see FIG. 3). Hereinafter, when there is no need to distinguish between them, they are collectively referred to as the ink cartridge 10 or the nozzle surface 12). A plurality of nozzles 12a for ejecting ink of each color are formed on each nozzle surface 12 side by side.

Returning to FIG. 2, the ink jet head 8 is arranged with each nozzle face 12 obliquely downward. The carriage 6 on which the inkjet head 8 is mounted is movably supported along the guide shaft 14 in the above-described direction, and is moved to a desired position by the carriage motor 16. The nozzle 12 of the inkjet head 8
a is extremely fine and easily clogged. Therefore, at one end of the moving range of the inkjet head 8 by the carriage 6, the following maintenance mechanism 20 is provided in the non-recording area.

A cap device 22 for individually protecting the nozzle surfaces 12 is provided at the outermost position (the right end in FIG. 2) of the moving range. The cap device 22 includes four protective caps 24 that cover the nozzle surface 12 in an airtight manner. When recording is stopped, the carriage 6 is moved to the position of the cap device 22 and the protective cap 24 of the cap device 22 is projected toward the nozzle surface 12. As a result, the nozzle surface 12 is covered with the protective cap 24 to seal the nozzle 12a, so that the nozzle 12a is not clogged due to drying of the ink or adhesion of external dust.

Further, at a position adjacent to the cap device 22,
An ink suction cap 26 is provided. The ink suction cap 26 hermetically covers the nozzle surface 12 in the same manner as the protection cap 24, and suctions ink inside the nozzle 12 a by making the inside of the nozzle 12 negative pressure by the suction pump 29. Thus, air, dust, and the like in the nozzle 12a are removed. It should be noted that even if the preliminary ejection of ink is performed on the nozzle surface 12 in the ink suction cap 26, air, dust, and the like can be removed in the same manner.

Further, a wiper 28 for wiping the nozzle surface 12 is provided at a position adjacent to the ink suction cap 26. After the suction by the ink suction cap 26 (hereinafter referred to as purging) or when recording is continued for a while, ink may adhere to the nozzle surface 12 and the adhered ink may cause the ejection direction to bend. You may not go. In such a case, the wiper 28 projects in the direction of the ink jet head 8 and wipes the nozzle surface 12 to remove the attached ink.

Next, a more detailed configuration of the ink jet head 8 will be described with reference to FIG. FIG. 1 shows the inkjet head 8 at the center of the yellow nozzle surface 12y.
Is shown in a vertical sectional view, but the ink jet head 8 is similarly configured for the other nozzle surfaces 12m, 12c, and 12b.

As shown in FIG. 1, the ink cartridge 1
0y ink discharge port 10a
Connected to the ink supply port 32 exposed behind the casing 8a. The ink supply port 32 communicates with the back of the head main body 34, and a nozzle plate 36 as a plate member is fixed to the front of the head main body 34. The nozzle plate 36 is formed of a polyimide resin into a flat plate shape, and has the above-described nozzles 12a (FIG. 3) formed therein. The front surface (left side in FIG. 1) of the nozzle plate 36 is a nozzle surface 12y.

The head main body 34 is constituted by using a piezo actuator, and is a well-known type that ejects ink supplied from the ink cartridge 10y through the ink supply port 32 through the nozzle 12a according to a control signal or the like.
Further, the nozzle plate 36 is adhered and fixed to the front surface of the head main body 34 via an adhesive 42 (FIG. 5).
It is exposed forward from the opening of a. A seal material 40 is filled between the inside of the opening and the head body 34,
The ink is prevented from entering the casing 8a. Furthermore, the area of the nozzle plate 36 is
4 is larger than the area of the front surface, and its peripheral edge is
4 Projecting around the front.

Next, a specific operation of the maintenance mechanism 20 will be described with reference to an example. The maintenance mechanism 20 can operate in various modes other than the operation described below, depending on the mode setting of the inkjet printer 1. At the time of recording suspension including the case where the power is off, as described above, the protection cap 2 of the cap device 22 is used.
Numeral 4 covers each nozzle surface 12 in an airtight manner. When the power is turned on, the cap device 22 moves the inkjet head 8
Then, the carriage motor 16 moves the ink jet head 8, and the nozzle surfaces 12b, 12c, 1
2m and 12y are sequentially arranged to face the ink suction cap 26. At this time, the ink suction cap 26 air-tightly covers the nozzle surface 12 disposed opposite to the ink suction cap 26, and executes the suction (purge) described above.

Here, the ink suction cap 26
The configuration and operation of (corresponding to a cap member together with the protective cap 24) will be described in further detail with reference to FIG. FIG.
As shown in FIG. 7, the ink suction cap 26 is made of an elastic material such as rubber, and the peripheral portion 26a is
It protrudes toward. The peripheral portion 26a is formed in a substantially rectangular frame shape slightly smaller than the front surface (the right side in FIG. 4) of the head main body 34, and the nozzle 12a on the nozzle surface 12
All are disposed inside the peripheral edge portion 26a. The inner portion of the peripheral portion 26a is connected to a hose 46 via a path 44, and the suction force of the suction pump 29 is transmitted through the hose 46.

The ink suction cap 26 is usually provided in the state shown in FIG.
As shown in (A), the nozzle is disposed at a retracted position that does not interfere with the nozzle surface 12. However, at the time of the purge, FIG.
As shown in (B), the peripheral portion 26 a is pressed against the nozzle surface 12. Then, all the nozzles 12a on the nozzle surface 12 are air-tightly covered with the ink suction cap 26, and by driving the suction pump 29 in this state, the nozzle 1
The air, dust and the like in 2a are removed via the path 44 and the hose 46. The protective cap 24 also has a similar peripheral portion, and the peripheral portion is used by being pressed against the nozzle surface 12.

After purging by the ink suction cap 26, ink may adhere to the nozzle surface 12. Then, following the above-mentioned purge, the wiper 28 projects,
As the carriage motor 16 moves the inkjet head 8 toward the recording area (to the left in FIG. 2), the nozzle surface 12 after the purging is wiped. After purging and wiping each nozzle surface 12 in this manner, when color image data is input, the carriage motor 16 moves the ink jet head 8, and the appropriate nozzles 12a eject ink. Then, the color image is printed on the recording paper 99. As described above, the nozzle surface 12
Since the dust and the like are surely removed by the maintenance mechanism 20, an extremely accurate image can be formed on the recording paper 99.

Here, in the ink jet head 8 of the present embodiment, the nozzle plate 36 is larger than the head main body 34, and its peripheral edge protrudes around the head main body 34. For this reason, as described below, the nozzle 12a
Can be prevented very well, and a very accurate image can be formed on the recording paper 99. FIG. 5 is an explanatory diagram illustrating the above-described effect of the inkjet head 8.

In the conventional ink jet head, the front surface (the upper side in FIG. 5) of the head body 134 and the nozzle plate 136
Were made to have the same area and shape, and both were adhered by the adhesive 42. For this reason, as illustrated in FIG. 5A, the adhesive 42 may protrude to the periphery of the bonding portion, so that not only the nozzle surface 112 cannot be completely wiped off at the time of wiping, but also the protruded adhesive 42 May wrap around the nozzle surface 112 of the nozzle plate 136. In this case, the adhesive 4 wrapped around the nozzle surface 112
No. 2 hinders the ejection of ink, so that not only can an accurate image not be formed, but also nozzle clogging may occur during wiping.

On the other hand, in the ink jet head 8, the nozzle plate 36 is larger than the front surface of the head main body 34, and its peripheral edge protrudes around the head main body 34. In addition, as shown in FIG. 5B, the protrusion width (projection amount) H is the thickness t of the nozzle plate 36 (1 in this example).
25 μm) or less (preferably about 3 times). For this reason, even if the adhesive 42 protrudes from the bonding portion between the nozzle plate 36 and the head main body 34, the adhesive 42 is provided behind the nozzle plate 36, that is, on the surface not facing the recording paper 99. Preferably, the protrusion width H is about 10 μm or more, so that the adhesive can be effectively prevented from flowing toward the nozzle surface. Therefore, the adhesive 42 is prevented from flowing around the nozzle surface 12.

Various external forces are applied to the nozzle plate 36, including the pressing force applied from the ink suction cap 26 and the like. For this reason, if H> 4 · t, when an external force is applied to the nozzle plate 36, the nozzle plate 36 may be deformed and an accurate image may not be formed. On the other hand, in the inkjet head 8, H /
Since t ≦ 3 to 4, it is possible to prevent the adhesive 42 from sneaking around the nozzle surface 12 to reliably prevent clogging of the nozzles 12a and to prevent the nozzle plate 36 from being deformed. 99 can form a very accurate image.

As described above, the present invention has been described with reference to the appropriate embodiments. However, the present invention is not limited to the above-described embodiments, and may be implemented in various forms without departing from the gist of the present invention. Can be implemented. For example, in the above embodiment, the nozzle plate 36 is made of a polyimide resin, but the nozzle plate 36 can be made of various materials. Also in this case, by setting H / t ≦ 3 to 4, it is possible to reliably prevent clogging and the like of the nozzle 12a and to form an extremely accurate image on the recording paper 99.

However, the applicant of the present application has a
Is made of a polyimide resin, the value of H / t is 3 to 4
It has been confirmed that the following makes it possible to extremely effectively prevent the adhesive 42 from wrapping around the nozzle surface 12 and the deformation of the nozzle plate 36. Therefore, in the ink jet head 8, the clogging of the nozzles 12a can be prevented more favorably, and a more accurate image can be formed on the recording paper 99. Further, the polyimide resin has such characteristics that the amount of deformation is small and that it has heat resistance (has heat resistance of about 300 ° C.). For this reason, in the inkjet head 8, there is also an effect that the adhesive 42 having a high curing temperature can be firmly bonded.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view illustrating a configuration of an inkjet head to which the present invention is applied.

FIG. 2 is a schematic perspective view illustrating a configuration of an ink jet printer having the head.

FIG. 3 is a perspective view illustrating a configuration of the head.

FIG. 4 is a cross-sectional view illustrating the configuration and operation of an ink suction cap of the printer.

FIG. 5 is an explanatory diagram showing an effect of the head.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Inkjet printer 8 ... Inkjet head 10 ... Ink cartridge 12 ... Nozzle surface 20 ... Maintenance mechanism 24 ... Protective cap 26 ... Ink suction cap 3
4: Head body 36: Nozzle plate 42: Adhesive 99: Recording paper

Claims (4)

(57) [Claims] A plate member having a nozzle surface on which a nozzle for ejecting ink is provided, and an end surface located on the opposite side to the nozzle member; and a head body which ejects ink through the end face of the plate member meet ink jet head formed by glued to the end face of the head body, the area of the end face of the plate member of said head body With the area of the end surface being larger than that of the end surface of the plate member, the peripheral portion of the end surface protrudes around the end surface of the head body ,
The protrusion amount of the peripheral portion is set to 3 to 4 times the thickness of the plate member.
Twice or less, and the adhesive spreads from the end face of the plate member to the nozzle face.
An ink jet head, wherein the protrusion is prevented by the protrusion of the peripheral portion . 2. The ink jet printer according to claim 1, wherein the ink jet printer is provided with a cap member for covering the nozzles in an airtight manner to prevent drying of the ink in the nozzles or sucking the ink in the nozzles. An ink jet head, wherein a peripheral portion of the cap member has a nozzle of the plate member.
An ink jet head, which is in contact with the surface of the ink jet head. 3. A plate member having a nozzle surface on which a nozzle for ejecting ink is provided, and an end surface located on the opposite side, a plate member provided behind the plate member, and head and body, and a casing having an opening exposing the plate member, the end face and is of the adhesion of the end face and the head body of the plate member for ejecting ink through
Met inkjet head that will be constituted by the area of the end face of the plate member is larger than the area of the end face of the head body, the projecting end surfaces of the plate member around the end face of the peripheral edge portion thereof above the head body To the end face of the head body so that the plate member
Ink jet head, characterized in that the head main body filled with the sealing material between the inner and the head main body of the opening of the casing also. (4) Nozzles for ejecting ink are provided
Plate member made of polyimide resin
When, Provided behind the plate member, through the nozzle
A head body for ejecting ink, And the end face of the plate member is connected to the end of the head body.
An inkjet head that is bonded to the surface with an adhesive
hand, The area of the end face of the plate member is set to the end face of the head body.
The area around the edge of the plate member
Part protruding around the end face of the head body,
The protrusion amount of the peripheral portion is 10 μm or more, and
3 to 4 times or less the thickness of the member, The nozzle where the adhesive is opposite to the end surface of the plate member
It is possible to prevent it from going around
An inkjet head characterized by the following.