JPH0121800Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a fine nozzle used in an inkjet device.

A commonly used fine nozzle is a drawn-out fine tube used in injection needles. These fine tubes are manufactured by drawing out metal tubes, but because of their dimensional variations, they cannot be used in cases where high precision is required. In addition, if the shape of the microtube is straight, it is possible to manufacture it, but stepped, tapered,
In the case of a rectangular cross section, it is almost impossible to manufacture it. Furthermore, when setting a plurality of these drawn fine tubes at a high precision pitch, it is difficult to ensure accuracy, and there is also a limit to the minimum dimension of the pitch. Another method for manufacturing fine nozzles is electroforming, but because of the fine dimensions (several tens of micrometers), it is difficult to manufacture a matrix.
It is almost impossible to manufacture due to the removal of the matrix. Furthermore, there are methods such as drilling, but they cannot be used due to dimensional accuracy. Still another method is to form etched fine grooves on the substrate, overlay the top plate on this, and bond the two together. Although this method does not have the above-mentioned drawbacks and is very good, it still has a problem in that it uses an adhesive, which can clog the fine grooves.

The present invention eliminates this drawback by forming fine grooves on the substrate and the upper plate by etching, overlapping the upper plate on the substrate, and fixing the two by spot welding. This will be explained below using figures.

The figure is a sectional view of a fine nozzle showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a substrate, on which fine nozzle grooves 2 of several tens of micrometers are formed by etching. Reference numeral 3 designates an upper plate, on which fine guide grooves 4 are similarly formed by etching. Although the groove width and pitch of the fine grooves 2 and 4 are approximately the same in plan view, the groove depth of the fine groove 4 is greater than that of the fine groove 2.
It may be shallower than that. That is, the fine grooves 2 have fixed dimensions designed based on the ink flow rate, etc., while the fine grooves 4 are formed to confirm the welding location when spot welding the substrate 1 and the upper plate 3. Therefore, if the depth of the groove 4 is such that it can be determined with the naked eye, a depth of several μm is sufficient. When performing spot welding, the surface of the upper plate 3 that does not have the grooves 4 is superimposed on the surface of the substrate 1 that has the grooves 2, so that the grooves 4 are located directly above the grooves 2, and the substrate 1 and the upper plate 3 are bonded together. Spot weld. If welding is performed at the BB portions of the grooves 2 and 4, the upper plate 3 may be deformed by the applied pressure and reliable welding may not be possible, so welding is performed at the outer AA portions of the grooves 2 and 4. Although stainless steel is normally used as the material for the substrate 1 and the upper plate 3, any metal may be used as long as it is not eroded by the sprayed liquid and can be spot welded.

As described above, according to the present invention, a fine nozzle with higher precision than electroforming or drawn blank tubes can be obtained, and fine nozzles exhibiting a tapered, stepped, or rectangular shape can also be easily obtained. The number of fine grooves is not limited to a single number, and even a plurality of grooves having a high precision pitch can be formed in the same manner. Since it is spot welded, reliable fixation is possible without blocking the groove with adhesive.
The locations to be welded can be easily identified by the grooves 4 in the upper plate 3. Further, although it is necessary for the fine nozzle to finally attach the piezoelectric element to the groove 4 located directly above the groove 2, the piezoelectric element can be accurately positioned by the groove 4. Substrate 1 and top plate 3
When performing the etching process, since both have the same dimensions, there is an advantage that the original film can be used in common. Although Macol material (ceramics) is sometimes used as the material for the upper plate 3, by using metal as in the present invention, the unit price can be reduced by two digits. Therefore, the fine nozzle of the present invention reliably prevents mutual interference of ink between the grooves, prevents clogging of the grooves, and can provide extremely high precision and low cost.

[Brief explanation of the drawing]

The figure is a sectional view of a fine nozzle showing an embodiment of the present invention. In the figure, 1 is a substrate, 2 is a fine groove for a nozzle, 3 is an upper plate, and 4 is a fine groove for guiding.

Claims (1)

[Scope of utility model registration request] It consists of a substrate in which fine grooves for nozzles are formed, and an upper plate in which fine grooves for guides having the same planar size as the fine grooves are formed on one surface, and the other parts of the upper plate are formed on the groove forming surface side of the substrate. A fine nozzle characterized in that, after overlapping their surfaces and positioning the two grooves so that they coincide, the substrate and the upper plate are fixed by spot welding (resistance welding) on the outside of the grooves.