JPH0671880A - Head of ink-jet recorder - Google Patents

Abstract

PURPOSE:To obtain a highly-reliable print head which is excellent in the priming property and ink spouting property that is not affected by a squeeze-out of adhesives. CONSTITUTION:A flow passage substrate 1 consists of two or more ink flow passages 1a, nozzles 1c which communicate with the ink flow passages 1a to spout ink, and false grooves 1b which make the joint widths around the ink flow passages 1a nearly constant. A cover plate 2 is bonded on the ink flow passage side of line flow passage substrate 1 with adhesives 4, so the ink flow passages 1a are almost kept airtight. Thereby, the amount of adhesive squeeze- out toward the ink flow passages is extremely small and even at any part of the ink flow passages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a head portion of an ink jet recording apparatus.

[0002]

2. Description of the Related Art In a head of an ink jet apparatus having a flow path substrate having an ink flow path and a cover plate bonded to the flow path surface side of the flow path substrate, the flow path substrate and the cover plate are bonded together. As shown in FIG. 11, since the adhesive is applied to the entire surface other than the ink flow path, which is the shaded area, the adhesive is likely to protrude into the ink flow path.

On the other hand, as shown in Japanese Patent Laid-Open No. 55-22911, a groove is formed in the bonded portion of the flow path substrate,
It has been proposed to reduce the protrusion of the adhesive into the ink flow path.

[0004]

As described above, in a head of an ink jet recording apparatus in which two plates are joined by an adhesive or the like to form an ink flow path, a head having high reliability without deteriorating performance is provided. To make it happen,
It is necessary to prevent the adhesive from protruding into the ink flow path as much as possible, or to set a constant amount of projection in any part of the ink flow path.

In the conventional case, the bonding width of the portion where the flow path substrate and the lid plate are bonded is different depending on the location, and the amount of the adhesive squeezed out is larger in the wide bonding part than in the narrow part.

As a result, it has been difficult to realize a highly reliable head which adversely affects the ink ejection performance and priming property.

Therefore, an object of the present invention is, in a head of an ink jet recording apparatus in which two plates are joined to form an ink flow path, the amount of the adhesive or the like that has been squeezed out after the joining is applied to any part of the ink flow path. The object is to realize a highly reliable head that has a small amount and is uniform and that has excellent ink ejection performance and priming properties.

[0008]

In order to achieve the above object, the head of an ink jet recording apparatus according to the present invention comprises:
A flow path substrate in which an ink flow path is formed, and a lid plate joined to the flow path surface side of the flow path substrate, at least one of the flow path substrate and the lid plate, the ink flow path periphery The non-bonding portion is provided to make the bonding width of the above-mentioned substantially constant.

The flow path substrate and the cover plate may be bonded with an adhesive.

Further, both the flow path substrate and the cover plate may be made of a plastic material, and both may be joined by an ultrasonic joining method.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a basic view for explaining a head structure according to the present invention. The flow path substrate 1 is formed with an ink flow path 1a and nozzles 1c that communicate with the ink flow path 1a and eject ink onto a recording medium. The cover plate 2 has an ink supply port 2a for supplying ink from an ink reservoir (not shown) and is bonded to the flow path substrate 1 with an adhesive 4, whereby the ink flow path 1a is in a substantially sealed state. .
Further, the flow path substrate 1 is provided with pressure generating means 3 including a piezoelectric element or the like.

The present invention relates to a so-called drop-on-demand type ink jet head, and the principle of ink ejection is generally well known.
The description is omitted here.

2 to 3 show a first embodiment of the present invention. The flow channel substrate 1 includes a plurality of ink flow channels 1a, nozzles 1c communicating with the ink flow channels 1a and ejecting ink onto a recording medium, and a ditch 1b for making the bonding width around the ink flow channels almost constant. It consists of The cover plate 2 has an adhesive 4
Is fixed to the ink flow path surface side of the flow path substrate 1.

The effect of the ditch 1b will be described with reference to FIG. (A) is a conventional example in which a waste groove is not provided, and the amount of protrusion of the adhesive 4 varies depending on the bonding width around the ink flow path, and as a result, the substantial cross-sectional area of the ink flow path changes. On the other hand, (b) is an embodiment in which the waste groove 1b is provided, and since the bonding width around the ink flow path is constant, the amount of the adhesive 4 protruding is minute and uniform, and the substantial cross-sectional area of the ink flow path is Does not adversely affect.

FIG. 5 shows a second embodiment of the present invention. The flow path substrate 1 is provided with a plurality of ink flow paths 1a and a waste hole 1b for making the bonding width around the ink flow paths substantially constant, and the same effect as the first embodiment can be obtained. .

FIG. 6 shows a third embodiment of the present invention, in which a ditch 2b is provided in the cover plate 2.

FIG. 7 shows a fourth embodiment of the present invention, in which cut grooves 1b and 2b are provided in both the flow path substrate 1 and the cover plate 2.

FIG. 8 shows a fifth embodiment of the present invention. The flow path substrate 1 is made of a plastic material, and is provided with a plurality of ink flow paths 1a, a ditch 1b for making the bonding width around the ink flow path almost constant, and a melting portion 1d that is melted by ultrasonic vibration. . On the other hand, the lid plate 2 is also made of a plastic material, and both are joined by an ultrasonic joining method.

Here, the effect of the ditch 1b will be described with reference to FIG. (A) is a conventional example in which the waste groove 1b is not provided, and the deformed shape of the fusion portion 1d after ultrasonic bonding differs depending on the bonding width around the ink flow path, and as a result, the substantial cross-sectional area of the ink flow path changes. . On the other hand, (b) is the waste groove 1b
In this embodiment, since the bonding width around the ink flow path is constant, the deformed shape of the fusion zone 1d after ultrasonic bonding is uniform and does not adversely affect the substantial cross-sectional area of the ink flow path.

Further, FIG. 10 shows a sixth embodiment. Here, it differs from the fifth embodiment only in that the melting portion 2c is provided on the lid plate 2, and the effect is the same as that of the fifth embodiment.

[0021]

According to the head of the ink jet recording apparatus according to the present invention, since the bonding width around the ink flow path is made substantially constant, the amount of the adhesive or the like after the bonding is small in every portion of the ink flow path. It is possible to realize a highly reliable head that can be made uniform and has excellent ink ejection performance and priming property. In addition, the same effect can be obtained even in the case of joining by ultrasonic joining, and a head of lower cost can be realized.

[Brief description of drawings]

FIG. 1 is a basic explanatory view of a head according to the present invention.

FIG. 2 is an explanatory diagram of a flow path substrate according to the first embodiment of the present invention.

FIG. 3 is an assembled sectional view of the head of the first embodiment of the present invention.

FIG. 4 is a sectional view for explaining the effect of the first embodiment of the present invention.

FIG. 5 is an assembled sectional view of a head according to a second embodiment of the present invention.

FIG. 6 is an assembled sectional view of a head according to a third embodiment of the present invention.

FIG. 7 is an assembled sectional view of a head according to a fourth embodiment of the present invention.

FIG. 8 is an assembled sectional view of a head according to a fifth embodiment of the present invention.

FIG. 9 is a sectional view for explaining the effect of the fifth embodiment of the present invention.

FIG. 10 is an assembled sectional view of a head according to a sixth embodiment of the present invention.

FIG. 11 is an explanatory view of a flow path substrate of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flow path substrate 1a Ink flow path 1b Non-bonding part 2 Lid plate 2b Non-bonding part 3 Pressure generating means 4 Adhesive

Claims (3)

[Claims] 1. A flow path substrate having an ink flow path formed therein, and a cover plate joined to the flow path surface side of the flow path substrate, wherein at least one of the flow path substrate and the cover plate. To
A head of an ink jet recording apparatus, characterized in that a non-bonding portion is provided for making the bonding width around the ink flow path substantially constant. 2. The head of an ink jet recording apparatus according to claim 1, wherein the flow path substrate and the cover plate are bonded with an adhesive. 3. The head of an ink jet recording apparatus according to claim 1, wherein both the flow path substrate and the lid plate are made of a plastic material, and both are joined by an ultrasonic joining method.