JPH0426046B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Technical Field] The present invention relates to a method for manufacturing a bubble tube type sensor for electrically measuring inclination.

[Conventional technology]

There are various types of bubble tube sensors that electrically measure inclination, and manufacturing methods for each type are known.

However, if a conductive wire is simply sealed to a glass tube and used as a probe, the friction between the conductor and the bubbles will hinder the smooth movement of the bubbles, so the resolution will not be high. Although this drawback can be eliminated with the conventional method, it is difficult to obtain sufficient strength in the sealed portion.

For example, when glass is melted and sealed, there is plating on that part, so the heat from melting the glass can damage the plating part, and when sealing with an adhesive such as epoxy, there is a plating on the part that is sealed inside. There was a problem with the strength of the sealing part against thermal distortion caused by the liquid being used and external temperature changes.

[Problem to be solved by the invention]

The present invention eliminates the above drawbacks, improves plating adhesion, has relatively high precision, provides a mask on the outside of the glass tube, and provides a contact pattern on the inside of the glass tube, making it suitable for mass production with stable quality. It is an object of the present invention to provide a method for manufacturing a bubble tube type sensor.

[Means to solve the problem]

In the present invention, a conductive wire is sealed in a glass tube, and after the conductor wire is sealed, the inner wall of the glass tube is polished to form a curved surface in order to obtain appropriate sensitivity as a bubble tube, and this curved surface is used for plating in the subsequent process. Then, a mask was placed on the outside of the glass tube, and a tactile pattern was placed on the inside of the glass tube using photo-etching technology and plating. By forming contact patterns of the same shape with intervals, the contact patterns are connected to the conductive wire, a negative electrode is provided between each contact pattern, and then a conductive liquid and air bubbles are enclosed. It is something that solves problems.

〔Example〕

Next, the procedure of the method of the present invention will be explained using specific examples shown in the attached drawings.

(i) Seal the conductive wire 2 to the glass tube 3 as shown in FIG. For example, a molybdenum wire with a diameter of 0.5 mm is sealed to a borosilicate glass tube with an outer diameter of 10 mm and an inner diameter of 8 mm.

(ii) As shown in FIG. 2, the inner surface of the glass tube 3 is polished to form an arc 6 corresponding to the desired level sensitivity. Polishing is carried out according to conventional methods. It is necessary to make the polished surface moderately rough. This is to improve the adhesion of plating described later. For example, using =1200 polishing sand as the polishing agent, the arc 6 is finished with a radius of R4585 mm (90°/2 mm).

(iii) The following operations are then carried out according to the known photoetching technique.

First, a photoresist 7 is applied to the inner wall of the glass tube 3 as shown in FIG.

Next, as shown in FIG. 4, the outer surface of the glass tube is masked using a tactile pattern mask 8, followed by photoprocessing, and the photoresist in non-exposed areas is removed as shown in FIG. During masking, the mask 8 is positioned at the center with reference to the central conducting wire. Masking and exposure can be performed from outside the glass tube, making the work easy.

(iv) Plating the entire inner wall of the glass tube 3 to form a plating layer 1 (FIG. 6). For example, acidic nickel solution plating is performed.

(v) As shown in Figure 7, the remaining resist is eluted and removed by immersion in a solvent for dissolving photoresist, thereby creating a tentacle consisting of a plating layer having the shape of the tentacle pattern shown in Figure 9. 9 is formed.

(vi) Finally, as shown in FIG. 8, conductive liquid 5 is sealed to complete the bubble tube type sensor 11. For example, a conductive liquid made by adding potassium iodide to a mixture of diethyl ether and ethyl alcohol is sealed. The bubble tube type sensor 11 made in this way is shown in FIG. 9 (upper front view) and FIG. 10 (bottom view).

In the bubble tube manufactured in this way, when the area involved with the bubble is equal between the left and right contactors, the difference in resistance value becomes zero, and if the inclination at this time is set horizontally, the difference in resistance value will occur due to the inclination. It is conventional practice to amplify the output by conventional means and make it proportional to the slope.

〔effect〕

By carrying out the above-described manufacturing process according to the present invention, it is possible to improve the adhesion of plating and to manufacture a stable bubble tube sensor with good sensitivity and precision. Furthermore, in the method of the present invention, it was previously difficult to create a tentacle pattern on the inside of a glass tube, but by providing a mask on the outside of the glass tube and creating a tentacle pattern on the inside of the tube, It is possible to manufacture a vial sensor using a photo-etching method and a plating process without using a vapor deposition method.This is a manufacturing method suitable for mass production, and if this method is followed, high efficiency can be achieved without quality variations. It can be manufactured by

[Brief explanation of drawings]

1 to 8 are explanatory diagrams sequentially showing the steps of a method for manufacturing a bubble tube type sensor according to the present invention. FIG. 9 is an upper front view of the bubble tube type sensor manufactured by the manufacturing method shown in FIGS. 1 to 8, and FIG. 10 is a bottom view thereof. 1...Plated layer, 2...Conducting wire, 3...Glass tube, 4...
Bubbles, 5... Conductive liquid, 6... Arc (radius R), 7
...Resist, 8...Mask, 9...Toucher, 11...Bubble tube type sensor, 12...Light source during exposure.

Claims (1)

[Claims] 1. A conductive wire is sealed in a glass tube, and after the conductor wire is sealed, the inner wall of the glass tube is polished to form a curved surface to obtain appropriate sensitivity as a bubble tube. A mask was placed on the outside of the glass tube, and a tentacle pattern was placed on the inside of the glass tube.The distance between the tentacles was set at the front and back of the glass tube using photo-etching technology and plating. They form a tentacle pattern of the same shape,
However, the contact pattern of the lever is connected to the conductive wire, a negative electrode is provided between each contact pattern, and then a conductive liquid and an air bubble are sealed. Manufacturing method.