JPS63280649A - Ink jet head - Google Patents

Abstract

PURPOSE:To enable simplification of a printing timing circuit, by arranging at least two nozzle orifices side by side in a direction perpendicular to a printing direction, in an ink-on-demand type ink jet head. CONSTITUTION:In a 24-nozzle ink jet head, tow nozzle orifices 1 are arranged in a direction perpendicular to a printing direction, and an ink led from an ink tank 9 into an ink supply preparatory chamber 4 is fed through ink- supplying passages 3 into pressure chambers 2. In this case, 12 ink ejection timings are controlled by an electric circuit, and a voltage is impressed on piezoelectric, whereby a volume change is caused in the pressure chambers 2, and ink droplets are caused to fly from the orifices 1. The orifices 1 are so arranged that when the resolution in the Y-axis direction is 180 dpi, the orifice pitch Y1 in the Y-axis direction is 0.141mm, the orifice pitch X in the X-axis direction is 1.41mm, and the interval Y2 between the two orifices 1 arranged side by side is Y2=Y1X12=1.693mm. Thus, a printing timing circuit can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention applies to ink-on-demand type inkjet heads having multiple nozzle orifices.

(Prior Art) Cross-sectional views of the ink flow path of an ink-on-demand type inkjet head are shown in FIGS. 14, 15, and 16.
Figure 4 shows a configuration with only one supply path 3 leading to the pressure chamber 2.
Figure 15 shows the pressure chamber 2 that was devised earlier by the inventor.
It has two supply passages 3 leading to the pressure chamber 2, and the nozzle orifice 1 is located on the supply passage 3. have,
Each figure shows a shape in which the nozzle orifice 1 is located above the pressure chamber 2.

FIG. 12 shows a conventional example of a 24-nozzle ink jet head constructed based on the flow path shown in FIG. 14, and the outline of the arrangement of the nozzle orifices 1 is shown in FIG. flT13. 24
The nozzle orifices l at the f2ir location are laid out in a straight line, maintaining a distance of WnY in the y-axis direction, so the dot spacing can be adjusted by moving the head feeding mechanism equipped with the inkjet head in the x-direction. It is possible to print characters consisting of 24 dots in the y direction, where Y is Y. However, since the nozzle orifices 1 are arranged at intervals of the distance Flix in the X direction, it is necessary to establish the timing of ink ejection based on the head feeding mechanism movement speed IfV and the interval X between the nozzle orifices 1 in the X direction. In the conventional example shown in Fig. 12, 2
4 nozzle orifices! Timing adjustment must be carried out for each, which has the problem of complicating the electric circuit and increasing costs.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, an object of the present invention is to provide an ink-on-demand type inkjet head that can reduce the complexity of an electric circuit due to print timing adjustment.

Another object of the present invention is to provide an ink-on-demand type inkjet head in which a plurality of nozzle orifices are formed in the same flat plate to easily obtain high positional accuracy of the nozzle orifices.

Another object of the present invention is to provide an ink-on-demand type inkjet head that can easily realize multi-color correspondence by providing ink channels and nozzle orifices corresponding to each color ink in the same flat plate. .

(Means for solving the problem) The ink-on-demand type inkjet head of the present invention includes an ink supply preparation chamber and a plurality of pressure chambers formed on one side of the same flat plate, each of the pressure chambers and the ink supply 1v
an ink supply path connecting chamber 11, the ink supply preparation chamber, the pressure chamber, and the ink supply path, located perpendicularly to the pressure chamber or the ink supply path, and on the opposite side of the flat plate. An ink-on-demand type inkjet head constituted by a plurality of nozzle orifices each having a small hole for ejecting ink 1^, characterized by means for arranging two or more nozzle orifices in parallel perpendicularly to the printing direction.

(Function) According to the present invention, in an ink-on-demand type inkjet head having a plurality of nozzle orifices, it is possible to simplify the printing timing circuit and to make the position of each nozzle orifice highly accurate within the same head. It is possible to make it multi-colored.

(Embodiment) Fig. 1 is an embodiment of the present invention, and is a conceptual diagram showing the flow path layout when two nozzle orifices l are arranged in parallel perpendicularly to the printing direction in a 24-nozzle ink jet head. be. Ink led from the ink tank 0 to the ink supply preparation chamber 4 passes through the ink supply path 3 and reaches the pressure chamber 2. By applying a voltage to the piezoelectric element 7, a volume change occurs in the pressure chamber 2 and the nozzle orifice! The principle is that the ink droplets fly further. The conventional 24-nozzle ink jet head shown in FIG. 12 requires one ink ejection timing for each nozzle, that is, 24 ink ejection timings. On the other hand, in the embodiment shown in Fig. 1, since the two nozzle orifices L are arranged side by side, it is only necessary to adjust the timing of ejecting 12 inks using an electric circuit (this makes it possible to keep the increase in circuit costs low). Although the various flow paths and nozzle orifices are shown transparently to make it easier to understand the internal causes, the structure including the diaphragm, piezoelectric element, etc. is the same as the previous drawing of the conventional example.

tjE2 is a conceptual diagram conceptually showing the arrangement of the nozzle orifice 1 based on the embodiment shown in FIG. X in the diagram
The axial resolution is 180 dPi (d.

L per 1nch), the nozzle orifice in the X-axis direction I? The a-distance Y is Y'+ = 0. 141
It means mm strip. Also, the width of the pressure chamber 2 in the X-axis direction is W
C" l m m N If the distance between pressure chamber 2 and the pressure chamber 2 adjacent to pressure chamber 2 is Dc = 0.41 mm, the distance between nozzle orifices 1 in the X-axis direction F + I X is X = t.

That would be 41mm. In particular, it is desirable that the interval X be an integral multiple of the resolution in the X direction, and that Fl'! Since Y is a 24-nozzle inkjet head, Y, = Y + X 12
= 1. (It will be 703 mm.X of nozzle orifice 1
The total width in the axial direction is XX11=15.5 m In.

FIG. 3 is also an embodiment of the present invention, and is a conceptual diagram showing a flow path layout when four nozzle orifices 1 are arranged in parallel perpendicularly to the printing direction in a 24-nozzle ink jet head. In this embodiment, it is only necessary to adjust the timing of ejecting six inks using an electric circuit, and it is possible to reduce the increase in circuit cost. Also, according to this flow path layout, the pressure chambers 2 can be arranged in parallel. As a result, in the manufacturing process of pasting the piezoelectric elements 7 on the pressure chambers 2, after pasting the large seat piezoelectric elements (shown with broken lines in Figure 3) on the plurality of pressure chambers 2, It is also possible to adopt an easy manufacturing method such as cutting the piezoelectric element 7 at one point (line part) using a cutting tool or the like according to the shape.

Figure 4 shows a nozzle orifice 1 based on the embodiment of Figure 3.
FIG. 2 is a conceptual diagram conceptually showing the arrangement of . In the figure, if the resolution in the X-axis direction is 180 dpi, the interval Y between nozzle orifices in the X-axis direction is Y.

=0.141mm. , the width of the pressure chamber 2 in the X-axis direction is W C = l m m N, and the distance between the pressure chamber 2 and the pressure chamber 2 adjacent to that pressure chamber 2 is Dc = 0.41.
If mm, then the interval X between nozzle orifices in the X-axis direction is X=2 (Wc+Dc)=2.82 mm. Also, between the nozzle orifices 1 arranged in parallel in the X-axis direction F
AY, is Yt = Y + xG = 0.847 mm,
The total width of the nozzle orifice 1 in the X-axis direction is XX5=14.
It will be 1mm.

FIG. 5 also shows an embodiment of the present invention, and in the 24-nozzle ink jet head shown in the embodiment of FIG.
Instead of arranging them in parallel, the pressure chambers 2 are arranged in a staggered manner to shorten the total width of the nozzle orifice 1 in the xfl11 direction! It is possible to improve the throughput by shortening the total width of the nozzle orifice l in the Ix axis direction. Here, the width of the pressure chamber 2 in the X-axis direction is W c = 1 mm N, and the distance between the pressure chamber 2 and the ink flow path of one example of the adjacent nozzle orifice is Dc =
0.41mm, Xf of ink flow path! The width in 11 directions is Wn
= 0.3 mm, the total width of the nozzle orifice l in the X-axis direction is 5 X ('wV c + 2 D c +
W n ) =: 10, 58 mm, making it possible to shorten the total width by 3.52 mm compared to 14.1 mm in the embodiment shown in FIG.

FIG. 6 is also an embodiment of the present invention, and is a conceptual diagram showing a flow path layout when six nozzle orifices 1 are arranged in parallel perpendicularly to the printing direction in a 24-nozzle ink jet head. In this embodiment, the timing of ejecting four inks can be adjusted using an electric circuit. Further, in this embodiment, the pressure chambers 2 are arranged in parallel, but it is also possible to arrange the pressure chambers 2 in a staggered manner as in the embodiment shown in FIG. 5 to shorten the total width in the X-axis direction.

FIG. 7 shows a nozzle orifice 1 based on the embodiment shown in FIG.
FIG. 2 is a conceptual diagram conceptually showing the arrangement of . y i11
If the direction resolution fi1 is 180 dpi, then [Y, is Y] between the nozzle orifices 1 in the X-axis direction.

=0.141mm. Further, if the width of the pressure chamber 2 in the X-axis direction is W c = 1 mm s, and the interval between the pressure chamber 2 and the adjacent pressure chamber 2 is Dc = 0.41 mm, then the interval between the nozzle orifices 10 in the X-axis direction is X = 3X
(Wc + Dc) = 4.23mm, so the total width of the first part of the nozzle orifice in the X-axis direction is 3X4.23 = 12
．． It will be 7mm.

FIG. 8 is also an embodiment of the present invention. In an ink-on-demand inkjet head having a new flow path configuration as shown in FIG. 15, which was previously proposed by the inventor, This is an example in which four nozzle orifices 1 are arranged in parallel in the direction.

FIG. 9 also shows an embodiment of the present invention, and in an ink-on-demand type inkjet head with a new flow path configuration as shown in FIG. 16, there are three nozzle orifices 1 in a direction perpendicular to the printing direction. This is an example in which they are juxtaposed.

FIG. 10 is a conceptual diagram showing the arrangement of the nozzle orifice 1 based on the embodiment shown in FIG. In this embodiment, since the distance Y between the nozzle orifices 1 in the X-axis direction depends on the lengths based on the shapes of the pressure chamber 2, ink supply path 3, and ink supply preparation chamber 4, FIG. It is difficult to arrange the nozzle orifices 1 close to each other in the y-axis direction as shown in the embodiment. However, the embodiment shown in FIG. 9 can be said to be suitable for a means of simultaneously printing a plurality of lines while the inkjet moves in the printing direction. Assuming a 180 dpi 72 nozzle ink jet head, Fil Y between nozzle orifices 1 in the y-axis direction.

= 0.141 mtns Width of pressure chamber 2 Wc = 1 mms Distance between pressure chamber 2 and adjacent pressure chamber 2 Fil I) c
= 0.41mm, the nozzle orifice l in the X-axis direction
The distance X=Wc+Dc=1.41 mm. : 1', and the interval between the nozzle orifices 1 arranged perpendicularly to the printing direction is Y* = 24 Also, the nozzle orifices 1 are formed on a single component, and high positional accuracy between the nozzle orifices 1 can be easily obtained.

In the above embodiments, the case where a single color printing ink is used has been described, but the present invention can also be applied to a multicolor inkjet head using two or more colors. That is, by providing an ink supply preparation chamber 4 for each color ink stream, and providing an ink supply path 3, a pressure chamber 2, and a nozzle orifice 1 connected thereto, this purpose can be easily achieved. Furthermore, by arranging ink flow paths and nozzle orifices compatible with multi-colors on a single component, the nozzle orifices can be easily aligned with each other! Accuracy is good.

FIG. 11 shows an example of a multicolor inkjet head. Six nozzle orifices are arranged vertically in parallel to the printing direction, with 12 nozzles for each color and 1 horizontal nozzle.
It has been pierced. Three colors of ink are used: yellow ink, cyan ink, and magenta ink, but if black ink and other inks are also used, this can be handled by additionally installing an ink flow path and nozzle orifice 1.

(Effects of the Invention) By using the ink-on-demand inkjet head having multiple nozzles according to the present invention, the printing timing circuit can be simplified, the positional relationship of each nozzle orifice can be easily highly accurate, and it can also be used for multi-color printing. It is possible to obtain an inkjet head which can be easily applied and which can greatly simplify the step of pasting the piezoelectric element (No. 4).

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing the ink flow path arrangement when two nozzle orifices are arranged perpendicularly to the printing direction according to the present invention. FIG. 2 is a conceptual diagram showing the nozzle orifice arrangement of FIG. 1. Figure 3 shows the nozzle oriice 4
FIG. 3 is a conceptual diagram of an ink flow path when two ink channels are arranged side by side. FIG. 4 is a conceptual diagram of the nozzle orifice arrangement. FIG. 5 is a conceptual diagram showing an embodiment in which the pressure chambers are arranged in parallel, and FIG. 0 is a conceptual diagram of an ink flow path when six nozzle orifices are arranged side by side. FIG. 7 is a conceptual diagram of the nozzle orifice arrangement. FIG. 8 is a conceptual diagram showing an embodiment in which two ink supply paths are connected to each pressure chamber. FIG. 9 is a conceptual diagram showing an ink flow path when a nozzle orifice is arranged at the center of a pressure chamber. FIG. 1O is a conceptual diagram showing the nozzle orifice arrangement. FIG. 11 is a conceptual diagram showing the ink flow path arrangement for multi-color. FIG. 12 is a conceptual diagram showing a conventional ink flow path arrangement, and FIG. 13 is a conceptual diagram showing a nozzle orifice arrangement. FIG. 14 is a sectional view of a conventional inkjet head. 1st
5 and 16 are cross-sectional views of conventional inkjet heads. The symbols are explained below. 1... Nozzle orifice 2... Pressure chamber 3... Ink supply path 4... Ink supply chamber 5... Channel substrate 6... Vibration plate 7... Piezoelectric element 8...・Ink supply tube 9...Ink tank and above Applicant: Seiko Epson Co., Ltd. Agent Patent attorney Aki Mogami and 1 other person・2~-11+!・Nostalgia Figure 1 Figure 1, Figure 3 Figure 4 Figure 8 Figure 9 Figure 11 Figure 13 Figure 14 Figure 15 Figure 16

Claims (1)

[Claims] An ink supply preparation chamber and a plurality of pressure chambers formed on one side of the same flat plate, an ink supply path connecting each of the pressure chambers and the ink supply preparation chamber, and the ink supply preparation chamber and the pressure chamber. a plurality of nozzle orifices located perpendicularly to the ink supply path and on the pressure chamber or the ink supply path, and having small holes for ejecting ink droplets formed on the opposite side of the flat plate; An inkjet head characterized in that two or more are arranged in parallel perpendicularly to the printing direction.