JPH04164835A - Method for boring glass plate - Google Patents

Abstract

PURPOSE:To efficiently form a small hole having high accuracy and quality through a glass plate by forming a man-penetrating hole on a glass plate by hot-pressing and removing the protrusion formed on the face opposite to the face having non-penetrating hole by grinding or polishing. CONSTITUTION:Non-penetrating holes 4... are formed on a glass plate 1 by hot-pressing (2: upper mold, 3: lower mold, 5: protrusion, 6: core pin) and the protrusions 5 formed on the face opposite to the face having the non-penetrating holes 4... are removed by grinding or polishing to form through holes (7: grinding wheel, 8: grinding Jig; 9: fixing wax, 10: work table).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a perforated glass plate used as a nozzle plate of an inkjet head for a printer or a substrate of a medical micropump.

[Conventional technology]

Glass is both a hard and brittle material and an insulating material. For this reason, cutting with a drill or electric discharge machining cannot be used as a processing method for drilling holes. Therefore, in the past, hole drilling was performed by grinding using a small-diameter grindstone with a shaft, or by free abrasive processing methods such as ultrasonic processing and sandblasting. In particular, the latter method of drilling holes using free abrasive processing is relatively highly productive and is often used as a mass production technique because it is possible to simultaneously process many holes by devising jigs and tools. However, when machining so-called small holes with diameters on the order of 0.5 mm, there are problems as described below. The biggest problem is poor processing accuracy. For example, in the case of ultrasonic machining, as the machining progresses, the tool wear progresses, resulting in a taper of 20% or more at the entrance and exit sides of the hole. In addition, chipping was likely to occur at the edges on the entrance and exit sides of the hole, and the accuracy and quality of drilling did not satisfy the function of the part. These problems are also common to the sandblasting method, and have been a bottleneck in its use as parts for precision devices. Also, especially 0.
When machining a small hole of about 5 rm, the rigidity of the ultrasonic machining tool is low (ultrasonic vibration does not work effectively on machining, and the machining force cannot be increased, so the machining speed is 11IffI/
gIa or less, resulting in low processing efficiency. Even in the case of the sandblasting method, the abrasive grains blown by the air jet enter the fine holes ((to become 1 r
The processing speed was approximately tm/si.

[Problem to be solved by the invention]

As described above, when drilling holes in a glass plate using the prior art, there have been problems in that the drilling accuracy is poor and the processing speed is slow. An object of the present invention is to provide a processing method that can efficiently process small holes with high precision and high quality.

[Means to solve the problem]

The method for forming holes in a glass plate according to the present invention includes forming non-through holes in a glass plate by hot press molding, and then removing protrusions that are formed on the surface opposite to the surface on which the non-through holes are formed by grinding or polishing. It is characterized by machining through holes.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention in the order of steps. The glass plate 1 is preheated for hot press molding. The heating temperature varies depending on the glass material, but is usually around the yield point (js) temperature. For example, the material of the glass plate is B
In the case of K7, it is 650°C. Next, as shown in FIG. 1 Ch), when press molding is carried out in a mold heated and kept at 500 to 400 DEG C., the narrow holes 4 become non-through holes and are molded by the upper mold 2. The glass that protrudes from the non-through hole during molding flows into the space provided in the lower mold 3 and is molded into the protrusion 5. The reason why through-holes are not formed by hot press molding is that hot press molding of glass is performed at high temperatures, so the strength of the core pin 60 formed in the upper mold 2 is low, and the viscosity of the material to be molded is high, making it difficult to penetrate in one shot. This is because it is difficult to machine holes. By performing the molding itself without blocking it as in the embodiments of the present invention, it is possible to reduce the molding resistance and it is also possible to process small holes. FIG. 1(C) shows a glass plate in which non-through holes and protrusions are formed in this manner. In this example, the depth of the small hole 4 is slightly smaller than the thickness of the glass plate 1. This is to remove the protrusion 5 in the later process to obtain a through hole. ) After fixing the glass plate 1 to the surface of the grinding jig 8 using fixing wax 9, the glass plate 1 is set on the work table 10 of a rotary grinder, and the protrusion 5 is ground off using the grinding wheel 7.

FIG. 1 (-) shows a glass plate that has undergone the above-mentioned processing steps to form small holes.

The accuracy and quality of the small holes processed by the processing method as in the above-described embodiments of the present invention were of high quality as shown in 5 below. Thickness 11
In the case of an example in which a small hole of φ0.5 wx was formed in a No. 111 glass plate, the hole diameter accuracy, including the taper, was within 1%. Furthermore, the surface roughness of the inner surface of the hole is approximately RmaIO45μ by mirror-finishing the mold core pin. The chipping of the hole opening edge can be kept to a level that does not pose a practical problem by appropriately selecting the grindstone used for removing the protrusion and the processing conditions.

〔Effect of the invention〕

According to the present invention, it is possible to efficiently machine high-precision, high-quality small holes in a glass plate, and parts for precision devices such as inkjet head nozzle plates for printers and substrates for medical micropumps can be manufactured at low cost. Stable production becomes possible.

[Brief explanation of drawings]

FIGS. 1(α) to 1(1) are cross-sectional views showing processing steps in an embodiment of the present invention. 1...Glass plate 2...Top Mold 5...Bottom Mold 4...Small hole 5.・−・・・・Protrusion 6・−−・・Core pin 7・・・Grinding whetstone 8・・・・・Grinding jig 9−−・−・・・Fixed wax

Claims (1)

[Claims] A glass characterized in that a non-through hole is formed in a glass plate by a hot press molding method, and then a protrusion formed on a surface opposite to the surface on which the non-through hole is formed is removed by grinding or polishing to form a through hole. How to drill holes in a board.