JPS60204370A - Wiring pattern - Google Patents

Abstract

PURPOSE:To provide a wiring pattern having uniform wiring resistance and high reliability, enabled in miniaturization and used in an ink jet recording head, constituted by bypassing wirings having a short wiring distance among a large number of wirings. CONSTITUTION:In an ink jet recording head, n-pieces of energy generators 5 are provided and a common electrode 6 is provided so as to be connected to one terminal of said energy generator 5 while wiring patterns are formed onto a flexible substrate 7 to be respectively connected to other terminals of the energy generators 5 as indivisual electrodes. The wiring patterns are connected to a connector part P3 through P1 and P2 parts. The wiring W1 having a short wiring distance of the P2 part is formed in a bent form to prolong the length of wiring even if the wiring distance is same to enhance wiring resistance and the wiring length is adjusted to obtain wiring patterns having uniform wiring resistance.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to wiring patterns, and particularly to wiring patterns intended to equalize wiring resistance. Regarding turns.

[Prior art]

The case of an inkjet recording head will be described below as an example.

FIG. 1 is a partial plan view of a wiring board of a conventional inkjet recording head.

In the figure, a plurality of wires are formed on a substrate 1 by etching to form wires/guts.

Conventionally, in the wiring of an inkjet head, the line density of the head portion is fine (more than 8 lines/w), and the line density of the connection part is higher (1 line/w or less).

For this reason, when routing wiring on the arm turn,
As shown in the diagram, the wiring is close to a straight line (for example, wiring 2)
And the wiring that has to be routed around (
For example, wiring 3) and wiring 3) had different lengths.

It has also been known for some time that the ink ejection limit voltage of an inkjet head is greatly affected by wiring resistance.

Conventionally, as shown in Figure 1, wires with short lengths (for example, wire 2) are narrowed in width, and long wires (for example, wire 3) are made wide in order to equalize the wire resistance. There was a need to change it.

However, if the width of the four turns of wiring is made too thin (
50 μm or less), the probability of wire breakage is high, and the etching precision of the wiring pattern has a large influence on the ejection limit voltage.

Furthermore, even if the head and part of the connector are on the same surface,
If the directions are different, as shown in FIG. 2, it would be necessary to twist the wiring using a longer flexible printed circuit board 4 or the like having a main turn. This was created in view of the conventional drawbacks, and its purpose is to provide a wiring pattern that has uniform wiring resistance, is highly reliable, and can be miniaturized.

[Summary of the invention]

In order to achieve the above object, the wiring pattern according to the present invention is characterized in that among the plurality of wirings, a wiring having a short wiring distance is detoured.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a plan view of one embodiment of the wiring pattern according to the present invention. However, in this embodiment, the case of an inkjet recording head is shown. In the figure, the inkjet recording head has n energy generating bodies 5 (for example, piezoelectric elements, electrothermal transducers, etc.).
and a common electrode 6 is provided at one end thereof. Also,
On the flexible substrate 7, the wiring and lean circuits of this embodiment are formed, and the energy generators 5 are connected as individual electrodes.
connected to the other end.

In this embodiment, the wiring width on the energy generating body 5 side is 40 μm.
m+ density 16 V fight/? The turn is Pl and P,
It is connected to the connector connection part P3 via the section.

The wiring width of the connector connection part P3 can be increased to 1.2 rts, but the shortest wiring distance a in the 22nd part
Since the ratio between the maximum wiring distance and the longest wiring distance is 1=5, it is necessary to take measures to equalize the wiring resistance. In the conventional countermeasure, the wiring resistance was made uniform by setting the width of the straight wiring W1 to 150 mm and the width of the wiring W2O to 30 μm. However, as already mentioned, in the case of a wiring width of 50 μm or less, the etching accuracy etc. The drawback was that it greatly affected the value. for example,
Assuming that all the wiring in section 21 is straight, if the wiring width is over-etched by 2 μm, the wiring resistance will change by about 5.7 inches.

Therefore, in this embodiment, the wiring Wi having a short wiring distance (1≦i≦4 in FIG. 3) is formed by bending.

Therefore, even if the wiring distance is the same, the length of the wiring can be increased, and the wiring resistance can be increased.

Therefore, the wiring width can be made wider than 50 μm. In this way, the length of each wiring Wi can be adjusted according to the wiring distance, and the widths of all the wirings W1 to Wn can be made wider than 50 μm, and the wiring resistance can be made uniform.

Of course, if the length of the wiring in the 1P1 section has a large effect on the wiring resistance, take that influence into account when determining the wiring W.
The length of 1 to Wn may be determined.

In this example, the part with different wiring density (Pl part)
and a portion (Pg portion) with different wiring directions are combined; however, the present invention is not limited to this, and either one may be used. In short, the present invention can be applied when the length of the wiring distance substantially affects the change in wiring resistance.

(5) Therefore, the present invention does not have to be used as an inkjet recording head bracket, but can be applied to any other type of wiring turn KJ.

Next, a case will be described in which another embodiment, which has only a portion (Pl portion) with a different wiring density and is connected to the connector connection portion P3 without changing the direction, is mounted on an inkjet recording head.

4 and 5 are perspective views of the recording head 8. FIG. An orifice 10 is provided in the case 9 of the recording head 8,
A common electrode 6 is exposed on the side surface. Furthermore, the wiring Wi (1≦l≦n) of the connector connection portion P is exposed on the back surface.

FIG. 6 is a sectional view taken along line I-1 in FIG. 4.

In the same figure, the flexible substrate 7 is arranged as shown in the case 9, and the energy generator 5 is provided at the position of the orifice 10. Ink is supplied from the ink tank 11 between the energy generator 5 and the case 9. The ink is ejected from the orifice 10 when a voltage is applied to the energy generator 5. Since the wiring is detoured, the resistance value of each wiring can be easily made uniform.

Moreover, since there is no need to narrow the wiring width, the yield of wiring patterning is improved. Therefore, when applied to an inkjet recording head, for example, the ink ejection limit voltage is constant for all nozzles. Stability of Hera P.

Improved reliability.

[Brief explanation of drawings]

FIG. 1 is a partial plan view of a wiring board of a conventional inkjet recording head, FIG. 2 is a perspective view showing an example of mounting a flexible printed circuit board, and FIG. 3 is an implementation of wiring/arm turn according to the present invention. FIGS. 4 and 5 are plan views showing examples, and FIGS.
It is a 1-1va sectional view in the figure. 7... Flexible substrate, 8... Inkjet recording head, 10... Orifice, W1 to Wn... Wiring. Part 4 @Figure 5

Claims (2)

[Claims] (1) In wiring/mother turns consisting of multiple wires,
A wiring pattern characterized by detouring wiring with short wiring distances. (2) The four-turn wiring according to claim 1, wherein the wiring having a short wiring distance is narrower than other wirings.