JP2000046628A - Electrode holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an insulator from being twisted off or deteriorated by the occurrence of cracks by forming a projection on the inner face of a connecting body, caulking one of the connecting body, and fastening the insulator. SOLUTION: This electrode holder 11 is provided with a metal electrode shaft 4 serving as an electrode body, a tubular connecting metal fitting 3 serving as a connecting body for fitting the electrode holder 11 to a liquid container 2, and a tubular insulator 5 insulating the electrode shaft 4 and the connecting metal fitting 3 and sealing a gap between them. An annular piece 3a is protruded on the middle inner face of the connecting metal fitting 3 as a projection bent upward (upper end side) and biting into the insulator 5, and a screw section 3c for fitting the connecting metal fitting 3 to a liquid container 2 is formed on the lower section outer periphery. A fitting face 3d larger than the screw section 3c in diameter is provided on the screw section 3c, and a hexagonal section 3e for screwing the electrode holder 11 to the liquid container 2 with a tool is provided on the fitting face 3d. The shape of the inner periphery formed by the annular piece 3a is preferably set to a polygonal shape, e.g. triangle, square or hexagon, or it may be set to a round shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode holder for holding an electrode used for controlling a liquid level of a boiler or a tank.

[0002]

2. Description of the Related Art FIG. 6 is a partial sectional view of a conventional electrode holder.

[0003] The electrode holder 1 includes a connection fitting 3 as a connection body for mounting to a liquid container 2 such as a boiler or a tank, and an electrode shaft 4 as an electrode body disposed at the center of the connection fitting 3. It has an insulator 5 made of, for example, fluororesin, which electrically insulates the metal fitting 3 and the electrode shaft 4 and seals a gap between them.

The electrode holder 1 is connected to a metal liquid container 2.
In an attached state, an electrode rod 8 for detection is connected to an end of the electrode shaft 4 on the side of the liquid container 2 by a connection nut 6 and a tightening bolt 7, and a tip of the electrode rod 8 to be detected is desired. It is located at the liquid level.

[0005] By detecting a change in the conduction state between the end of the electrode shaft 4 to which the wiring 9 outside the liquid container 2 is connected and the liquid container 2, the liquid level in the liquid container 2 changes to the level of the electrode. It is detected whether or not the tip of the rod 8 has been reached.

[0006]

In such a conventional electrode holder 1, the electrode shaft 4, the connecting fitting 3, and the insulator 5 are provided.
Are integrally formed by injection molding, and the upper end 3 of the connection fitting 3 is formed.
b, the upper end 3b and the connecting metal 3
The insulator 5 is tightened between the hook-shaped annular piece 3a protruding from the inner circumference of the middle to secure the sealing property. A thin portion of the insulator 5 exists between the two.

For this reason, if the connection nut 6 is excessively tightened when attaching the electrode rod 8 for detection to the electrode shaft 4, the insulator 5 integrated with the electrode shaft 4 tries to rotate integrally with the connection nut 6, and the insulation There is a drawback that the thin portion of the body 5 may be cut off or cracked, resulting in deterioration of insulation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above technical problems, and provides an electrode holder in which insulation is prevented from deteriorating due to a screw cut or a crack in an insulator. With the goal.

[0009]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, the present invention according to claim 1 comprises a connector for attaching the electrode holder to the container, and an insulator surrounding the outer periphery of the electrode and insulating the electrode from the connector. An electrode holder having a protrusion formed on an inner surface of the connection body, and crimping one end of the connection body to clamp an insulator between the one end and the protrusion; A notch is formed at the other end of the body, and the other end is caulked to make close contact with the insulator.

According to a second aspect of the present invention, there is provided a connector for attaching the electrode holder to the container, and an insulator surrounding the outer periphery of the electrode and insulating the electrode from the connector. In the electrode holder, a protrusion is formed on an inner surface of the connection body, and one end of the connection body is caulked so as to clamp an insulator between the one end and the protrusion. A protrusion for preventing rotation is formed on the outer periphery.

According to a third aspect of the present invention, in the configuration according to the first aspect, a plurality of the notches are formed along a circumferential direction of the tubular connecting body.

According to a fourth aspect of the present invention, in the configuration according to the second aspect, a plurality of the protrusions are formed along a circumferential direction of the electrode body.

According to a fifth aspect of the present invention, in the configuration according to any one of the first to fourth aspects, the projecting portion formed on the inner peripheral surface of the cylindrical connecting member is bent toward the one end. Is what is done.

According to the first aspect of the present invention, a notch is formed at the other end of the connecting body, and the other end is caulked to closely adhere to the insulator, so that the electrode rod is connected to the electrode body via the connection nut. At the time of connection, even if a force is applied to rotate the electrode body and the insulator integrated therewith, the other end of the connecting body is intimately biting into the insulator, so that the rotation of the insulator is prevented. Will be.

According to the second aspect of the present invention, since the protrusion for preventing rotation is formed on the outer periphery of the electrode body, when the electrode rod is connected to the electrode body via the connection nut, the electrode body and Even if a force acting to rotate the insulator integral therewith acts, the insulator covering the outer periphery of the electrode body prevents the protrusion from rotating, that is, acts to prevent the rotation of the electrode body.

According to the third aspect of the present invention, since the plurality of cutouts are provided along the circumferential direction of the cylindrical coupling body, the rotation of the insulator integral with the electrode body is more reliably prevented. Will be.

According to the fourth aspect of the present invention, the protrusion is
Since the plurality of electrodes are formed along the circumferential direction of the electrode body, the rotation of the electrode body is more reliably prevented.

According to the fifth aspect of the present invention, the insulator between the protruding portion bent to one end and the one end to be caulked is tightened to improve the sealing performance.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an electrode holder according to the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a partial cross-sectional view of an electrode holder according to Embodiment 1 of the present invention, and portions corresponding to the conventional example in FIG. 6 are denoted by the same reference numerals. .

The electrode holder 1 ₁ of this embodiment includes a metal electrode shaft 4 as an electrode material, a cylindrical connecting fitting of the electrode holder 1 ₁ as a coupling member for attachment to a liquid container 2 3 and a cylindrical insulator 5 that insulates the electrode shaft 4 and the connection fitting 3 and seals a gap between them.

An annular piece 3a, which is bent upward (to the upper end side) and bites into the insulator 5, protrudes from the middle inner surface of the connection fitting 3, and a liquid outer periphery is provided on the lower outer periphery. screw portion 3c for attachment to the container 2 is formed, the upper portion has a mounting surface 3d of the larger diameter than the threaded portion 3c, further to its upper, liquid container the electrode holder 1 ₁ by means of a tool 2 has a hexagonal portion 3e for screwing. The shape of the inner periphery formed by the annular piece 3a is preferably a polygon such as a triangle, a square, or a hexagon, but may be a circle.

The lower end of the electrode shaft 4 is connected to an electrode rod 8 which is suspended in the liquid container 2 via a connection nut 6 and a fastening bolt 7. The upper end side of the electrode shaft 4 serves as a terminal for wiring 9 to a measuring device (not shown).

The insulator 5 that insulates the electrode shaft 4 from the connection fitting 3 has electric insulation as described above, and also seals a gap between the electrode shaft 4 and the connection fitting 3. When used as a liquid level sensor such as a boiler or the like, a material having chemical resistance, heat resistance and the like is used. For example, a fluororesin such as PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) can be used. Further, as those having high resistance to hot water, ketone-based synthetic resin materials such as polyetheretherketone and aromatic polysulfone-based synthetic resin materials such as polyethersulfone are preferable.

In this embodiment, as in the conventional example of FIG. 6, the electrode shaft 4, the connection fitting 3 and the insulator 5
The connecting piece 3 is integrally formed by injection molding while holding the connecting piece 3 in a predetermined positional relationship, and the upper end 3b of the integrally formed connecting piece 3 is swaged to form an annular piece 3a.
The insulator 5 is tightened and sealed between them.

[0027] The electrode holder 1 _1, as described above,
At the lower end of the electrode shaft 4, an electrode rod 8 which is suspended in the liquid container 2 via a connection nut 6 and a fastening bolt 7 is connected. The portion where the thickness of the insulator 6 is thin, that is, the portion where the thickness of the insulator 5 is thin due to the formation of the annular piece 3a, in which the integral insulator 5 tries to rotate integrally with the connection nut 6 The insulation property is deteriorated due to a thread cut or a crack. However, in order to prevent such a problem, the following configuration is adopted.

That is, in this embodiment, as shown in FIG. 2 and FIG. 3 which is a cross-sectional view taken along the line AA of FIG. 2, the electrode shaft 4, the connection fitting 3 and the insulator 5 are
After being integrally formed by injection molding, the upper end 3b and the lower end 3f of the connection fitting 3 are each caulked.

Further, the lower end 3f of the connection fitting 3 is provided with the structure shown in FIG.
As shown in (2), notches 3h are formed at two opposing positions, whereby the lower end 3f is caulked so as to bite into the insulator 5 to be closely attached.

As described above, the notch 3h is formed at the lower end 3f of the connecting fitting 3 and swaged, so that the connecting fitting 3 is formed.
When the electrode rod 8 is connected to the electrode shaft 4 via the connection nut 6, even if a force to rotate the electrode shaft 4 is applied, the electrode shaft 4 is integrated with the electrode shaft 4. The rotation of the insulator 5 is prevented by the lower end 3f of the connection fitting 3, so that the thin portion of the insulator 5 where the annular piece 3a protrudes is screwed or cracked. It can be prevented from entering.

As described above, since the lower end 3f of the connection fitting 3 is also swaged, the rotation of the insulator 5 can be prevented as described above, and the sealing performance is improved as compared with the conventional example in which only the upper end 3b is swaged.

The number and shape of the cutouts are not limited to those in the above embodiment, but may be arbitrarily selected.

FIG. 4 (Embodiment 2) is a partial sectional view of the electrode holder 1 ₂ of the second embodiment of the present invention, the portion corresponding to the conventional example of FIG. 6, the same reference numerals Is attached.

In the above-described embodiment, the lower end 3f of the connecting member 3 is cut into the notch 3h and swaged, thereby causing the lower end 3f of the connecting member 3 to bite into the insulator 5 so that the insulator 5
Rotation but was configured to block, and in this embodiment, the outer periphery of the electrode shaft 4 _2, to a position above annular piece 3a of the connecting fitting 3, the plane of FIG. 5 (a), (b) as shown in Figure and a front view, the projections 4 ₂ a for rotation prevention for preventing rotation of the electrode shaft 4 ₂ is projected in two locations at an interval of 180 degrees. These projections 4 ₂ a is formed into small pieces along the axial direction of the electrode axis 4 _2.

The upper insulator 5 of the annular piece 3a, connecting the upper end 3b painter with connecting fitting 3 by caulking are tightly integrated, electrode shaft 4 the electrode rod 8 to ₂ the lower end of the connecting fitting 3 nuts when connecting through 6, even if the force for rotating the electrode shaft 4 ₂ acts, the projections 4 ₂ a for the rotation preventing may be prevented from rotating by an insulator 5 of the outer periphery to be, thereby, it can be prevented or Nejikire rotation of the electrode shaft 4 ₂ and insulator 5 is blocked by the meat thin portion of the thickness of the insulator 5 of the annular piece 3a is projected, from crack become.

The formation position, number and shape of the rotation preventing protrusions 4 ₂ a are not limited to the above-described embodiment, but can be arbitrarily selected. However, since the insulator 5 is firmly integrated with the connection fitting 3, the rotation preventing action works more preferably, which is desirable.

(Other Embodiments) The above-described embodiments may be combined, and a protrusion for preventing rotation may be formed on the electrode shaft, and a cutout may be formed on the lower end of the connecting fitting to be swaged. .

[0038]

As described above, according to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, a notch is formed at the other end of the connecting body, and the other end is caulked to adhere to the insulator, so that when connecting the electrode rod to the electrode body, Even if a force is applied to rotate the electrode body and the insulator integrated therewith, the other end of the connecting body is intimately biting into the insulator, so that the insulator is prevented from rotating. As a result, it is possible to prevent the insulation from being deteriorated due to the occurrence of a screw cut or a crack in the thin portion of the insulator.

According to the second aspect of the present invention, since the projection for preventing rotation is formed on the outer periphery of the electrode body, when the electrode rod is connected to the electrode body, the electrode body and the insulator integrated therewith are formed. Even if a force is applied to rotate the insulator, the insulator covering the outer periphery of the electrode body prevents the projection from rotating, that is, acts to prevent the electrode body from rotating. Therefore, it is possible to prevent the insulation from deteriorating due to a screw cut or a crack at a thin portion of the insulator.

According to the third aspect of the present invention, since the plurality of cutouts are provided along the circumferential direction of the cylindrical connecting member, the rotation of the insulating member is more reliably prevented, and the screw of the insulating member is prevented. Cuts and cracks can be prevented.

According to the fourth aspect of the present invention, the protrusion is
Since a plurality of electrodes are formed along the circumferential direction of the electrode body, the rotation of the electrode body and the insulator integrated therewith is more reliably prevented, so that the insulator can be prevented from being screwed or cracked.

According to the fifth aspect of the present invention, the insulator between the bent protruding portion of the connecting body and the one end to be caulked is tightened, and the sealing performance is improved.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of Embodiment 1 of the present invention.

FIG. 2 is a partial cross-sectional view showing a procedure for manufacturing the electrode holder of FIG.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2;

FIG. 4 is a partial cross-sectional view of Embodiment 2 of the present invention.

FIG. 5 is a view showing an electrode axis of FIG. 4;

FIG. 6 is a partial sectional view of a conventional example.

[Explanation of symbols]

1,1 _1, 1 ₂ electrode holder 2 liquid container 3 connecting fitting 3h cutout 4,4 ₂ electrode shaft 4 ₂ a protrusion

Continued on the front page (72) Inventor Masaru Fukuda 12-15 Nisone, Kokura-minami-ku, Kitakyushu-shi, Fukuoka F-term (reference) 2F014 AA14 AB01 DA01

Claims (5)

[Claims] 1. A connection body for attaching the electrode holder to a container, and an insulator surrounding the outer periphery of the electrode body to insulate the electrode body from the connection body. The electrode holder in which a protruding portion is formed and one end of the connecting body is caulked so as to tighten an insulator between the one end and the protruding portion, wherein a notch is formed at the other end of the connecting body. An electrode holder characterized in that the other end is caulked and brought into close contact with an insulator. 2. A connecting body for attaching the electrode holder to a container, and an insulator surrounding the outer periphery of the electrode body to insulate the electrode body from the connecting body. Is an electrode holder in which a protruding portion is formed, one end of the connecting body is caulked, and an insulator is tightened between the one end and the protruding portion. An electrode holder characterized in that the electrode holder is formed. 3. The electrode holder according to claim 1, wherein a plurality of the notches are formed along a circumferential direction of the tubular connecting body. 4. The electrode holder according to claim 2, wherein a plurality of the protrusions are formed along a circumferential direction of the electrode body. 5. The electrode holder according to claim 1, wherein the protrusion formed on the inner peripheral surface of the cylindrical connector is bent toward the one end.