JP2848296B2 - Electrostatic suction type inkjet printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle substrate and a counter electrode substrate in an electrostatic suction type ink jet printing apparatus.

[0002]

2. Description of the Related Art Conventionally, a nozzle substrate provided with a plurality of nozzles for ejecting ink and a counter electrode substrate provided on the other side are provided on one side via a paper transport surface, and the nozzle substrate has a number corresponding to the number of nozzles. 2. Description of the Related Art An electrostatic suction type inkjet apparatus having a configuration in which an electric pattern circuit for controlling a printing voltage is incorporated is known. Among them, conventionally, the nozzle is not particularly protruded in the direction of the sheet conveying surface, and the surface of the counter electrode substrate is flat.

[0003]

In recent years, in order to cope with the increase in the number of print dots, there is a tendency to increase the additional voltage for printing to each nozzle in order to eject the ink from each nozzle as little as possible. . However, such a high voltage causes a complicated structure and a large size of the nozzle substrate. Therefore, it is desired to provide a configuration which can provide a sufficient printing effect even at a voltage as low as possible.

[0004]

The present invention uses the following means in order to solve the above problems. That is, first, in the electrostatic suction type inkjet printing apparatus having a configuration in which a nozzle substrate provided with a plurality of nozzles for ejecting ink and a counter electrode substrate are arranged via a paper transport surface, A portion of the counter electrode substrate facing each nozzle is projected toward the paper transport surface.

Second, in the electrostatic suction type ink jet printing apparatus having the above-mentioned structure, a protruding portion of the nozzle or a spacer which is longer than the protruding portion of the counter electrode substrate is attached to the nozzle substrate or the counter electrode substrate. .

Third, in an electrostatic suction type ink jet printing apparatus having a structure in which a nozzle substrate having a plurality of nozzles for ejecting ink and a counter electrode substrate are arranged via a paper conveying surface, each nozzle or A portion of the counter electrode substrate facing each nozzle is protruded toward the paper transport surface, and the nozzle substrate or the counter electrode substrate has a height higher than that of the nozzle or the counter electrode substrate. Attach the spacer.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic structural view of a nozzle head portion of an electrostatic suction type ink jet printing apparatus according to the present invention, in which a protruding structure is provided for both a nozzle substrate 1 and a counter electrode substrate 2, and FIG. FIG. 3 shows the case where only the protruding structure is provided, and FIG.
It is a figure in case only a protruding structure is provided.

1 to 3, a nozzle substrate 1 is provided on one side (in the present embodiment, upper side) of the sheet P via a conveying surface of the sheet P.
On the other side (similarly below), a counter electrode substrate 2 is provided. The upper portion of the nozzle substrate 1 serves as an ink tank 1b for filling the ink I. From the bottom surface of the nozzle substrate 1,
A plurality of nozzles 1a for ejecting ink are opposed to the transport surface of the lower sheet P.

When a voltage is applied to each nozzle 1a, an electric field is generated on the opposing electrode substrate 2 below, and ink I is ejected from each nozzle 1a along this electric field, and printing is performed on the surface of the paper P being conveyed. However, in order to prevent the ink jet from scattering as much as possible, it is necessary to generate the electric field generated from each nozzle 1a to the counter electrode substrate 2 as intensively as possible. As a means for that,
In the present invention, the distance between the nozzle tip and the electrode is made as small as possible.

For this reason, in FIG. 1, each nozzle 1a protrudes below the nozzle substrate 1 (that is, toward the paper transport surface side), while the counter electrode substrate 2 faces each nozzle 1a. The protruding portion 2a is formed by projecting the portion to be projected upward (that is, toward the sheet transport surface side). 2, only the nozzles 1a are made to protrude, and in FIG. 3, only the projections 2a of the counter electrode substrate 2 are made. Either one may be adopted depending on the structure of the printing apparatus to be configured.

Thus, the nozzle 1a and the projection 2
By protruding a, the electric field is concentrated, and the effect of enabling clear printing even at a low voltage is achieved.
Since the sheet P protrudes from the conveying surface, the possibility of interference between the projecting portion and the sheet P increases.

Therefore, as shown in FIG. 1, in each of the substrates 1 and 2, the nozzle 1a
In addition, spacers 3.3 are provided which are higher (H1> h1, H2> h2) than the protruding portions of the projections 2a from the surfaces of the substrates 1 and 2. By disposing the spacers 3, 3 at the insertion entrance portion between the two substrates 1, 2, the feeding of the paper P becomes smooth, and the substrate 1 of the nozzle 1a and the projection 2a is formed. 2 Because it is taller than the protruding part from the surface,
The transport surface of the paper P between the two substrates 1 and 2 is the nozzle 1a
The posture is maintained substantially constant between the tip and the tip of the projection 2a,
Does not shift too much vertically. Therefore, the paper P is smoothly conveyed without interfering with the nozzles 1a and the protrusions 2a, and does not hinder printing.

When only the nozzle 1a has a projecting structure without the projection 2a as shown in FIG. 2, the spacer 3 may be provided only on the nozzle substrate 1. On the other hand, as shown in FIG. As described above, in a case where the nozzle 1a is not protruded and the protruding portion 2a is provided on the counter electrode substrate 2,
The spacer 3 may be provided only on the counter electrode substrate 2.

[0014]

As described above, the present invention has the following advantages. That is, since the configuration as described in claim 1 is used, the space between the nozzle and the portion of the counter electrode substrate opposed to each nozzle is narrowed, so that the printing additional voltage applied to the nozzle is low. Even if the structure of the nozzle substrate (nozzle head) itself is not complicated or enlarged, an electric field is intensively generated from the nozzles to the counter electrode substrate, and the printing is sharpened, which leads to cost reduction.

Further, in the configuration of the first aspect, since the configuration is as described in the second aspect, even if the configuration is such that the nozzle protrudes or the portion of the counter electrode substrate facing each nozzle protrudes, Smooth paper conveyance can be ensured without the paper interfering with the protruding portion.

Further, since the present invention is configured as described in claim 3,
The concentration of the electric field between the nozzle and the counter electrode substrate is further increased, which contributes to lowering the voltage, simplifying the nozzle head, miniaturizing the device, and consequently reducing the cost.
It can be expected that paper transport will be further smoothed.

[Brief description of the drawings]

FIG. 1 is a schematic structural view of a nozzle head portion of an electrostatic suction type inkjet printing apparatus according to the present invention, in which a nozzle substrate 1 and a counter electrode substrate 2 are both provided with a protruding structure.

FIG. 2 is a view showing a case where a protruding structure is provided only on the nozzle substrate 1;

FIG. 3 is a view showing a case where a protruding structure is provided only on the counter electrode substrate 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nozzle board 1a Nozzle 1b Ink tank 2 Counter electrode board 2a Projection part 3 Spacer P Paper I Ink

Claims (3)

(57) [Claims] In an electrostatic suction type ink jet printing apparatus having a configuration in which a nozzle substrate having a plurality of nozzles for ejecting ink and a counter electrode substrate are arranged via a paper transport surface, each of the nozzles or the counter nozzle is provided. An electrostatic suction type ink jet printing apparatus characterized in that a portion of an electrode substrate facing each nozzle is protruded toward a paper transport surface. 2. The electrostatic suction type ink jet printing apparatus according to claim 1, wherein a protruding portion of said nozzle or a spacer which is longer than a protruding portion of said counter electrode substrate is attached to said nozzle substrate or said counter electrode substrate. An electrostatic suction type ink jet printing apparatus characterized by the above-mentioned. 3. An electrostatic suction type inkjet printing apparatus having a configuration in which a nozzle substrate provided with a plurality of nozzles for ejecting ink and a counter electrode substrate are arranged via a paper transport surface. A portion of the electrode substrate facing each nozzle is projected toward the paper transport surface, and a spacer having a height higher than the projection of the nozzle or the projection of the counter electrode substrate is provided on the nozzle substrate or the counter electrode substrate. An electrostatic suction type inkjet printing apparatus characterized by being attached.