JPS59187864A - Recording head - Google Patents

Abstract

PURPOSE:To make high speed printing possible and secure mixing color recording by preventing lower nozzles from being contaminated, by providing a guide passage so that the ink flowed dower from upper nozzle may not be in contact with lower part nozzle. CONSTITUTION:Different color ink of, for example, yellow, magenta, cyan etc. are fed to ink jet nozzles H1, H2 and H3 from an ink supply pipe 1P. Control chip CP1 is fixed to substrate PC1, further respectively fixed to substrates HS1-HS3, etc., and furthermore are mutually arranged in zigzag with respect to a common substrate K. This substrate K is loaded onto a carriage and recording is carried out while moving it in both directions of arrow marks A and B. In this case, the ink DD flowing down from upper nozzle H3 is received by an ink guide passage 1G in order not to contaminate the lower nozzle H1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field) The present invention relates to a color inkjet recording head, and particularly to a recording head that can perform high-speed recording and prevent nozzle stains.

(Conventional) Conventionally, in this type of recording head, a plurality of nozzles for color ink jet recording were arranged parallel to the moving direction of the carriage. For this reason, for example, tba yellow α]
, magenta (Ml), cyan (C1).
When discharging ink to mix colors, both Y+M+C and C+M+Y occur depending on the direction of movement of the carriage, resulting in different color tones.

Therefore, bidirectional recording cannot be performed, and there is a limit to the improvement in recording speed in unidirectional recording. Therefore, a configuration in which a plurality of inkjet nozzles are arranged in a direction perpendicular to the moving direction of the carriage is also known.

However, in this case, there was a risk that the lower nozzle would be contaminated by the ink carelessly flowing down from the upper nozzle, resulting in a decrease in recording quality.

(Objective) In view of the above-mentioned difficulties, the present invention provides a guide path so that the ink flowing down from the upper nozzle does not come into contact with the lower nozzle.

(Example) Fig. 1 is a perspective view of an example of the present invention, and PP is a recording A'4
L H1, H2, and H3 are inkjet nozzles, and yellow ω is produced by each ink supply pipe IP.

Unique colored inks such as magenta (B) and cyan (E) are supplied.0 cp1H control chip is fixed to the printed circuit board PC1,
They are each fixed to the substrates H81 to H8, 1S, etc., and further arranged in a staggered manner on the common substrate K. It is mounted on a carriage (not shown) on the substrate, and performs recording while moving in both directions of arrow AB.

For example, the inkjet nozzle generates air bubbles selectively in each ink chamber by causing a heater in each ink chamber to generate heat.
The droplet DP can be attached to the paper PP by the force, and various other mechanisms such as a piezoelectric element can be used. If the nozzles are arranged in a direction almost perpendicular to the moving direction AB of the carriage in this way, for example, inadvertent ink DD that flows down from the upper nozzle H will stain the lower nozzle H1 and cause color mixing, which will deteriorate the recording quality. This causes a decrease in the amount of water.

Therefore, the falling ink DD is stopped and downward c)
, y, y:h H1 An ink guide path IG is provided to guide the ink DD to a place where it will not be contaminated.

With such a configuration, it is possible to avoid contamination of the lower nozzle, and to prevent a decrease in recording speed and recording quality.

Various structures can be set for the ink guide path IG as long as they do not pollute the nozzles below.

It is also clear that this configuration is highly effective even when applied to a system that performs only one-way recording.

FIG. 2 is a diagram showing a control method that can further prevent staining of the platen PL due to inadvertent ejection of ink onto the platen PL.

In other words, when the recording paper PP has not reached the front surface of the platen PL, ejecting ink from the nozzles will stain the platen PL, and when the recording paper PP is subsequently loaded, ink will adhere to the & side of the paper. Resulting in. In order to eliminate this drawback, a paper position detection means such as a light emitting element L is used.
A light receiving element PS is provided, and the nozzles H1 and H2 are made operable in response to the detection result.

Further, by setting the nozzles in the order of operation starting from the lower nozzles and turning the upper nozzles into a drivable state, the nozzles can be operated reliably when mixing colors on the recording paper.

That is, if the upper and lower nozzles are driven simultaneously or from above when mixing colors, the area recorded by the upper nozzle cannot be subsequently covered with ink of another color, resulting in wasted paper.

Therefore, as shown in the figure, there is provided a one-shot multi-by-break OS1 that starts up in response to the output of the light-receiving PS, and a one-shot multi-by-break OS2 that starts up in response to the falling edge of the OS1, and by stubbornly starting these, the AND gate A1 , A2 are opened in order so that the image information from the control unit CC is first applied to the lower nozzle H1, and then applied to the upper nozzle H2.

(Effects) With this configuration, mixed color recording can be achieved reliably and without staining, which is extremely preferable.

[Brief explanation of the drawing]

The first item is a perspective view of an example of the present invention, and FIG. 2 is an example diagram of its control circuit. H1~H6・-・ll11 Ink jet nozzle work G・
... Ink guide path PP ... Recording paper

Claims (1)

[Scope of Claims] In a recording device in which a plurality of inkjet nozzles are arranged in a direction substantially perpendicular to the moving direction of a carriage and ink of a different color is supplied to each nozzle, there is provided a method for guiding ink flowing down from an upper nozzle. A recording head whose main feature is to prevent contamination of the lower nozzle by providing a passage.