JPS594309B2 - inkjet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-nozzle type inkjet recording apparatus that is equipped with a plurality of ink ejecting nozzles so that a plurality of ink droplets can be ejected toward a recording medium at once for recording.

The present invention also provides an inkjet recording apparatus in which a plurality of ink jet nozzles can be easily arranged closely so that high-density dot matrix characters can be printed. FIG. 1 is a sectional view showing a recording head portion of a conventional multi-nozzle inkjet recording apparatus described in Japanese Patent Application Laid-Open No. 52-49033.

1 is a platen, and ink droplets are ejected from the recording head 3 onto a paper 215 supported on the platen to record dots, and characters, symbols, designs, etc. are recorded by combinations of dots.

Since this recording head is of a multi-nozzle type, a plurality of nozzles 4 are arranged in a row, and each ink flow path 5 is connected to a plurality of nozzles 4.
It communicates with a common ink chamber f06 via. A piezoelectric element 7... is provided in the middle of each ink flow path, and by selectively driving these piezoelectric elements, the nozzle 4.
Ink is selectively ejected from... This ink jetting operation is performed in synchronization with the spacing operation of the print head 3. 5. As a result, characters etc. are recorded on the paper 2. However, in the case of a multi-nozzle type, since the nozzles 4 with minute diameters must be closely arranged, it is difficult to process and form the nozzles 4 and the flow passages 5 near the nozzle portions. Especially for printing kanji etc.
This becomes a major problem when 10 or more nozzles are arranged at a minute pitch. In addition, in order to arrange a large number of nozzles and ink channels in the manner shown in Figure 1, the cross-sectional area of the channels must also be made small, which increases resistance during ink flow and increases pressure loss. 5. Therefore, the flight distance of the ink is short and the flight speed is low. In order to solve such problems,
As described in Japanese Patent No. 1-9622, only the nozzle portions are arranged in one row or several rows, but the ink channels communicating with the nozzles are formed in a direction perpendicular to the nozzles and almost radially downward, so that each A configuration is known in which the other end is communicated with the ink chamber.

Fig. 2 is a front view of the print head having this radiating ink flow path, and Fig. 3 is a sectional view taken along line A-A'' in Fig. 2. In the figure, N1 to N, 2 are ink jet nozzles. , are arranged in two rows in a staggered manner.These nozzles N, ~Nl
2 is connected to the radial ink flow path G, ~Gl2, and the outer end of the radial ink flow path G, ~G, 2 is connected to the cylindrical ink flow path G, ~G, 2 which also serves as the ink supply path C, ~C, 2. Piezoelectric elements P1 to P
, 2. The other ends of the ink supply paths C1 to C, 2 are connected to a common ink chamber as in the case of FIG. 1. In this way, each nozzle N, ~Nl2 is connected to the radial underground flow path G1
By connecting the ink flow paths G1 to G,2 to the ink chamber through G,2, the distance between the ink flow paths G1 to G,2 can be increased. The configuration shown in Figure 4 is adopted.

That is, grooves g1 to Gl2 communicating with the nozzles N, to N, 2 are formed on the back surface of the plate GP in which the nozzles N, to N, 2 are bored, and by covering the substrate B over the grooves, the radial underground flow path G is formed.
, ~Gl2 are formed. In this way, the channels that flow ink to each nozzle extend radially from each nozzle in the direction of the surface perpendicular to the nozzles, so the channels 5... The intervals between the flow paths G1 to Gl2 are sufficiently wide compared to those in which the . is extended.
For this reason, processing and formation of the flow path becomes easier, and it becomes easier to miniaturize the arrangement pitch of the nozzles. Further, since there is a margin in the flow path interval, it becomes easy to increase the cross-sectional area of the flow path itself, as shown in the flow paths G4 and G5 shown by chain lines. If the cross-sectional area of the flow path is large in this way, the flow resistance of the ink is small, so the pressure loss from the piezo elements P, to P, 2 to the nozzle portion is small, and the ink can be ejected effectively. Note that a surface plate F in which nozzles are drilled with higher precision may be superimposed on the surface of the plate material GP on which the radial underground flow path is formed. If the distance between the nozzles is relatively wide, or if the number of nozzles is small, such a configuration can be put to practical use, but simply forming the ink flow paths radially downward makes it difficult to arrange a large number of nozzles closely together. is impossible, and the number of nozzles is limited to t)3, so it cannot be applied to devices that require a large number of nozzles, such as a Kanji printer.

It is an object of the present invention to solve these problems in conventional quick-jet print heads, and to make it possible to easily arrange each nozzle close to each other even when the number of nozzles increases, while keeping the ink flow paths relatively separated. The purpose is to make it possible to set up the

In order to achieve this object, the present invention provides an ink channel in which an ink flow path that communicates an ink jet nozzle with an ink chamber is formed radially downward from a nozzle dense area in a plane substantially perpendicular to the nozzle direction, that is, the ink jet direction. In the printed print head,
The ink flow path is distributed in multiple layers, and a nozzle is provided at the tip of each ink flow path.

Next, examples will be used to explain how the quick-jet print head according to the present invention is actually implemented.

FIG. 5 is a front view of a quick-jet print head according to the present invention, and FIG. 6 is a sectional view taken along line B-B'' in FIG. 5. In FIGS. 2 and 3, within a single plane, While all channels G1 to Gl2 are formed, in FIGS. 5 and 6, a large number of channels are distributed in two layers. For example, odd numbered channels G1, G3,・・G2l・G
23... are formed between the first plate member GPl and the second plate member GP2, and are even numbered flow paths G2, G4...G22,
G24... are formed between the second plate material GP2 and the substrate B. More specifically, the odd numbered nozzle N1″
・N3″...N2l″N,! ... was opened first
A groove leading to the odd-numbered nozzle is formed on the back surface of the plate material GPl, and by covering the groove with the second plate material GP2,
First layer channels, that is, odd numbered channels G1, G3...G
2l.G23... are formed. Similarly, even numbered nozzles N2ζN4'-...N22ζN24'...
Grooves communicating with the even-numbered nozzles N2'', N4'-...N22ζN24'', etc. are formed on the back surface of the second plate material GP2 with the openings, and by covering the grooves with the substrate B, the second plate material GP2 Layered channels, that is, even numbered channels G2, G4...
・G22, G24... are formed. And, the other end of each flow path G1, G2...G2l, G22...
Cylindrical closed piezoelectric elements P, .P, . . . P2, .P22 .
is connected to. Moreover, in addition to the odd numbered nozzles N, .
... is also opened, and when assembled, the second plate material GP2
The nozzles N2ζN4'-...N22', N24ζ, and so on are arranged to overlap with each other. In the illustrated example, the odd-numbered channels are provided in the first layer, and the even-numbered channels are provided in the second layer, but the channels can be further multilayered into three or four layers and subdivided. You can also do so.

In this way, by providing the radial flow channels communicating with the nozzles in different layers for every other nozzle or every plurality of nozzles, the spacing between adjacent flow channels within one layer can be adjusted to the distribution layer. becomes wider in proportion to the number of Therefore, processing of the flow path and expansion of the width of the flow path are easier than in the examples shown in FIGS. 2 and 3, and it is especially suitable for an ic-jet recording head in which a large number of nozzles are densely packed. Plate material F-GPl/GP
2. To laminate the substrate B etc., plate materials such as stainless steel may be glued together, but radiating grooves and nozzles are provided in photosensitive glass called photoceram, and this is laminated and heated. It can also be integrated. In addition, in the case of FIGS. 3 and 6, the radial depression grooves for forming the flow path are formed on only one side of the plate material, but for example, in FIG. Grooves can also be formed. As described above, according to the present invention, the ink flow path that communicates the ink jetting nozzle with the ink chamber is formed radially downward from the nozzle dense area in a plane substantially perpendicular to the nozzle direction, that is, the ink jetting direction. In the print head, the ink channels are formed in a plurality of layers, and a nozzle is provided at the tip of each ink channel, so that the radial ink channels are dispersed into the plurality of layers.

Therefore, even in the case of a print head that requires a large number of nozzles, such as a Kanji printer, it is possible to arrange a large number of nozzles close together and the ink channels to be spaced apart.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the recording head portion of a conventional multi-nozzle type ic jet recording device, FIG. 2 is a front view of a conventional print head having a radiating ink flow path, and FIG. -N sectional view, FIG. 4 is a back view of the plate material GP in FIG. 3, FIG. 5 is a front view of the print head showing an embodiment of the print head according to the present invention, and FIG. 6 is a B-B'' in FIG. FIG.

Claims (1)

[Scope of Claims] 1. In a print head in which an ink flow path that communicates an ink jetting nozzle with an ink chamber is formed radially from a nozzle dense area in a plane substantially perpendicular to the nozzle direction, that is, the ink jetting direction. , the ink channels are distributed in multiple layers,
An inkjet recording device characterized in that a nozzle is provided at the tip of each ink flow path. 2. The ink flow path formed in multiple layers in a plane perpendicular to the nozzle is formed by overlapping multiple plates with grooves formed on at least one side, and on the side where the groove is open at the end. The inkjet recording device according to claim 1, wherein the inkjet recording device is formed by stacking other plate materials.