JPH0541376Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Industrial Application Field) The present invention relates to an electromagnetic flowmeter detector, and particularly to an electrode of a measuring tube made of an insulating material.

(Prior Art) In a so-called liningless electromagnetic flow meter detector in which the entire measuring tube is an insulator, especially one in which the measuring tube is made of ceramics, conventionally an electrode 62 is attached to the measuring tube 61 as shown in FIG. The structure is such that it is made airtight by packing 63 and inserted from inside the measuring tube 61, and fixed and held by spacer 64, spring 65, and nut 66. However, this structure not only has a complicated electrode structure, but also has a large number of parts, which raises concerns about reliability.
There were drawbacks such as complicated installation work.

(Problems to be solved by the invention) As mentioned above, conventional electromagnetic flowmeter detectors using measuring tubes made of insulating materials have complicated electrode structures, a large number of parts, concerns about reliability, and poor installation. There were problems such as complicated work. Therefore, an object of the present invention is to provide an electromagnetic flowmeter detector that solves the above-mentioned problems.

[Structure of the idea]

(Means for solving the problem) The electromagnetic flowmeter detector of the present invention has a plug-shaped member made of a relatively soft conductive material inserted into an electrode hole provided at a predetermined position on the wall of a measuring tube made of an insulating material. The structure is such that the plug-shaped member is used as an electrode.

(Function) The electromagnetic flowmeter detector of the present invention is achieved by simply fitting a plug-shaped member made of a relatively soft conductive material into an electrode hole provided in the wall of a measuring tube made of an insulating material by press-fitting or driving. Since the electrode has no leakage, the structure of the electrode is simple and there is no need for parts for fixing and sealing the electrode, making it easy to assemble, and since no packing is used, it is corrosion resistant and resistant. It also has high temperature resistance.

(Example) Hereinafter, the present invention will be explained in detail based on the example shown in the drawings. Figures 1a and 1b show a measuring tube of an electromagnetic flowmeter detector according to an embodiment of the present invention. Measuring tube 1 is made of ceramics (alumina, zirconia, silicon nitride,
Made from forsterite, steatite, etc.)
At a predetermined position, in this example, in the center of the measuring tube 1, in the tube wall on the diameter axis perpendicular to the tube axis, a tapered electrode hole 2 whose diameter decreases toward the inside of the tube is inserted. An electrode 3 made of a plug-like member made of a relatively soft conductive material, such as platinum with high corrosion resistance, is attached with an interference fit. If the tapered electrode hole 2 is opened before firing the ceramic measuring tube 1, it is usually sufficient to do no finishing work after firing. The electrode 3 is made of a tapered plug-like member similar to the tapered electrode hole 2, and is inserted into the tapered electrode hole 2 by driving or press-fitting using a driving jig such as a punch. By deforming the electrode 3 so that it comes into close contact with the tapered electrode hole 2,
It is fixed to keep it airtight.

In the electromagnetic flowmeter detector according to the embodiment of the present invention, which is equipped with the measuring tube 1 configured as described above, the structure of the electrode 3 is simple, and parts for fixing and sealing the electrode are not required. It is easy to assemble, and since no packing is used, it has high corrosion resistance and high temperature resistance.

Note that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications as described below.

[a] As shown in FIG. 2, the shape of the electrode hole 12 is a simple straight round hole, the electrode 13 is also a simple cylindrical shape, and a jig 1 is placed inside the measuring tube 1.
4, and then press-fit the electrode 13 to deform it and install it in an airtight manner.

[b] As shown in Figure 3 a and b, electrode hole 2
The shape of the electrode 2 is a drum shape with both ends widened, and the shape of the electrode is a cylindrical electrode 13 as shown in FIG. A contact jig 14 is placed inside the measuring tube 1, and the electrode is press-fitted by placing it inside the measuring tube 1, thereby deforming the electrode and installing it in an airtight manner.

[c] As shown in Figure 4 a and b, electrode hole 3
2 has a countersunk shape in which only the tip end on the inner wall side of the measuring tube 1 widens, and a cylindrical electrode 13 as shown in FIG. 4a or a countersunk-shaped electrode 23 as shown in FIG. 4b is used.
A contact jig 14 is placed inside the measuring tube 1, and the electrode is pressed into the measuring tube 1, thereby deforming the electrode and installing it in an airtight manner.

[d] As shown in Figure 5 a and b, the electrode hole 4
2 is shaped like a barrel with tapered ends, and the 5th
A cylindrical electrode 13 as shown in FIG. Install airtight.

[e] As shown in Fig. 6 a and b, the measuring tube 21
is formed into a shape having a thick wall portion 21a with a small inner diameter in the required range near the electrode mounting position, and an electrode hole 52 is formed at a predetermined position to have a depth corresponding to the wall thickness of the measurement tube 21 other than the thick wall portion. , a cylindrical electrode 13 is implanted and press-fitted, and the electrode is deformed and installed in an airtight manner. Thereafter, the thick portion 21a is removed by cutting to obtain a measuring tube with a predetermined inner diameter.

[f] As shown in Fig. 7 a and b, the measuring tube 31
The required area near the electrode mounting position is the partition wall 31a.
An electrode hole 52 having a depth corresponding to the predetermined wall thickness of the measuring tube 31 is made at a predetermined position, and a cylindrical electrode 13 is driven and press-fitted to deform the electrode and make it airtight. Install. Thereafter, the partition wall 31a is removed by cutting to obtain a measuring tube with a predetermined inner diameter.

[g] As shown in FIGS. 8a and 8b, an electrode hole 52 having a depth corresponding to the wall thickness of the completed measuring tube is made in a predetermined position of the solid measuring tube base material 41, and a circular A columnar electrode 13 is implanted and press-fitted, and the electrode is deformed and installed in an airtight manner. Thereafter, concentric holes of a predetermined diameter are formed in the measurement tube base material 41 as shown by the two-dot chain line to obtain a measurement tube having a predetermined inner diameter.

[Effect of idea]

As detailed above, according to the present invention, a hole for an electrode is provided at a predetermined position on the tube wall of a measurement tube made of an insulating material such as ceramics of an electromagnetic flowmeter detector, and a relatively soft conductive material is used for this hole. The electrode is made of a plug-shaped member that is driven in and press-fitted to ensure an airtight installation, which simplifies the structure of the electrode and eliminates the need for parts for fixing and sealing the electrode, making it easy to assemble. Since no packing is used, it has high corrosion resistance and high temperature resistance.

[Brief explanation of the drawing]

Figures 1a and 1b show a measuring tube of an electromagnetic flowmeter detector according to an embodiment of the present invention, Figure 1a is a sectional view, Figure 1b is a side view, Figures 2 and 3 are a, b. , Figure 4a,
b, Figure 5 a, b, Figure 6 a, b, Figure 7 a,
8a and 8b are schematic diagrams of the main parts showing different modifications of the present invention, respectively, and FIG. 9 is a sectional view of the main parts showing the electrode structure of a conventional electromagnetic flow meter detector equipped with a measuring tube made of ceramics. It is. 1...Measuring tube, 2...Tapered electrode hole,
3...Tapered electrode, 12...Straight electrode hole, 13...Cylindrical electrode, 14...Abutment jig, 22...Trumpet-shaped electrode hole, 23...Countersunk electrode , 32...Countersink-shaped electrode hole, 33...Spherical or ellipsoidal electrode, 42...Barrel-shaped electrode hole, 21...Measuring tube, 21a...Thick walled part, 52
... Electrode hole, 31 ... Measuring tube, 31a ... Partition wall, 41 ... Measuring tube base material.

Claims (1)

[Claims for Utility Model Registration] (1) In an electromagnetic flowmeter detector having a measuring tube made of an insulating material, an electrode made of a relatively soft conductive material is tightly fitted into an electrode hole in the wall of the measuring tube. An electromagnetic flowmeter detector comprising a plug-like member. (2) The electromagnetic flowmeter detector according to claim 1, wherein the material of the measuring tube is ceramics. (3) The electromagnetic flowmeter detector according to claim 1, wherein the material of the electrode is platinum.