JPS6033771B2 - Manufacturing method of capillary glass tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing capillary glass tubes used for physical and chemical purposes and as parts of various instruments.

There are generally two methods for manufacturing capillary glass tubes: hand-blowing and machine-blowing, but the hand-blowing method has problems with accuracy and has the disadvantage that it is difficult to mass-produce products of a certain standard. be.

In addition, manufacturing using the machine blowing method is perfect in terms of precision and mass production, but it is not profitable unless it is produced in a certain quantity or more, so the price becomes extremely high when producing small quantities of non-standard products, and the machinery itself There is also the problem that they are expensive and cannot be purchased from general manufacturers. In addition, since the demand for special capillary glass tubes is extremely small, there is the problem that even if they are produced in large quantities, the stock will accumulate and it will not be profitable. In view of the above-mentioned points, the present invention aims to provide a method for manufacturing a capillary glass tube that can easily and freely manufacture the inner and outer diameters without using an automatic machine. According to the method, it is possible to easily manufacture a special capillary glass tube a having a thick wall and a small hole in the center, as shown in FIG. 1, for example.

In FIG. 2, b is a glass component formed by thinly slicing a glass tube as shown in FIG. Manufacturing is also possible. Next, embodiments of the present invention will be described based on the descriptions shown in the drawings. The materials and devices necessary to carry out the present invention are a glass tube 1 which is a raw material formed with appropriate inner and outer diameters, and a A metal gauge hole 2 that can be freely inserted into the la and determines the inner diameter of the capillary glass tube to be the product, and has a cylindrical shape with an inner diameter that can at least fit against the outer circumferential surface of the glass tube 1. They are a correction glass tube 3, a suction fitting 4 for vacuum forming equipped with a vacuum pump 5, and a heating furnace (not shown).

First Embodiment The first embodiment is as shown in FIGS. 3 to 7.
First, the gauge hole 2 that determines the inner diameter is inserted into the hole la of the existing glass tube 1, which is the raw material, and the tube is placed in a heating furnace and heated as shown by the arrow in Figure 3 to complete the first step. do.

The glass tube 1 that has completed the first step is heated and shrinks until the inner diameter of the hole la comes into close contact with the gauge hole 2 as shown in Figure 5, so the hole la becomes a small diameter hole 1 as shown in the figure, and the glass tube The entire tube 1 also becomes a capillary glass tube 1' with a diameter of 4 mm. Next, as a second step, a cylindrical glass tube 3 is fitted around the outer circumference of the capillary glass tube 1' to correct the outer dimensions of the capillary glass tube 1' to predetermined dimensions as shown in FIG. As shown in FIG. 7, a suction fitting 4 is fitted to the ends of both glass tubes 1' and 3, and the gas accumulated in the gap between both glass tubes 1' and 3 is drawn out by the action of a vacuum pump 6. together with both glass tubes 1'
, 3 are placed in a heating furnace and heated as indicated by the arrows in FIG. If you take out gauge 2, you will get the predetermined outer diameter (thickness) as shown in Figure 1.
A capillary glass tube a can be obtained. If you want to make the inner diameter of the capillary glass tube a to be manufactured, that is, the hole a', smaller, you can use a smaller gauge gauge 2. If you want to make the outer diameter of the product even larger, the dimensions to be used should be Either increase the wall thickness of the correction cylindrical glass tube 3 or prepare another cylindrical glass tube with a large diameter, and sequentially iron a plurality of cylindrical glass tubes around the outer periphery of the capillary glass tube 1'. It can be vacuum formed.

Second example In this embodiment, manufacturing is completed in one step.

That is, a gauge punch 2 is inserted into the hole la of a glass tube 1 that is a raw material, and a cylindrical glass tube 3 for dimensional correction is iron mounted around the glass tube 1, and the ends of both glass tubes 1 and 3 are At the same time, the suction fitting 4 is placed on the gauge plate 4, and then the gauge village 2 is heated and vacuum formed.
By drawing the capillary glass tube, the inner diameter and outer diameter are manufactured at once. When both glass tubes 1 and 3 are heated and vacuum formed, they will shrink and the overall diameter will become smaller, so as in the case of the first embodiment, the shrinkage rate is taken into account in advance and the thickness of the cylindrical glass tube is adjusted. It is necessary to determine the thickness. Since the present invention is as described above, the inner diameter of the capillary glass tube can be freely shaped by using a gauge punch, and by preparing in advance a plurality of cylindrical glass tubes with different outer diameters and wall thicknesses, By using the so-called block molding method of equal cylindrical glass tubes, they can be molded into any size and size.
All that is required for manufacturing equipment is a vacuum forming machine.Furthermore, when welding the glass tubes, the gas remaining between the two glass tubes is drawn out using the vacuum forming machine (pump) mentioned above. The present invention also has the advantage of being able to weld tubes in a short time and more accurately. Therefore, according to the present invention, capillary glass tubes can be produced in small quantities and in a wide variety of products with high precision, extremely simply and at low cost. This is a revolutionary manufacturing method compared to conventional hand-blowing and machine-blowing methods.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a capillary glass tube manufactured according to the present invention, FIG. 2 is a perspective view of a glass component manufactured by slicing the capillary glass tube as shown in FIG. 1, and FIGS. FIG. 7 shows an embodiment of the present invention showing the manufacturing process in order. FIG. 3 is a side view of a glass tube with a gauge punch inserted, and FIG. 4 is a cross-sectional view taken along line A-A in FIG. 1. , FIG. 5 is a cross-sectional view of the capillary glass tube manufactured in the first step, FIG. 6 is a cross-sectional view showing the capillary glass tube manufactured in the first step with a cylindrical glass tube fitted with iron, and FIG. The figure is a cross-sectional view showing a simplified state of vacuum forming. 1...Glass tube, la...hole, 2...gauge village, 3...
...Tubular glass tube, 4...Suction fitting, 5...
···Vacuum pump. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1. A gauge rod for determining the inner diameter is inserted inside the glass tube, and a cylindrical glass tube is fitted on the outer peripheral surface of the glass tube to correct the outer diameter to a predetermined size. ,
A capillary glass tube characterized in that the gas remaining in the gap between these two glass tubes is extracted by a vacuum pump, and the entirety of both glass tubes is heated to fuse them together, and then the gauge rod is pulled out. manufacturing method.