JPH05273030A - Support structure of measuring rod for electrostatic type level meter - Google Patents

Abstract

PURPOSE:To eliminate poor insulation with excellence in heat resistance, insulating property and durability by arranging a two-layer cover having a sprayed alumina ceramics layer as lover layer and a silicone rubber layer as upper layer laminated on the surface of a part where a measuring rod pierces an outer cylinder. CONSTITUTION:A measuring rod 1 has a tapered bulge 3 with a larger diameter at a connection with an outer cylinder 2 and a cover is applied on the part. In the covering, a layer sprayed with alumina ceramics 4 is formed on the surface of a part where the measuring rod 1 pierces the outer cylinder 2 and a silicone rubber layer 5 is formed thereon. The thickness of the cover is, for example, 1mm for the alumina ceramic layer and 1mm for the silicon rubber layer. In such a support structure, the cover is excellent in the heat resistance and insulating property and high in durability thereby eliminating poor insulation or the like even when used in a storage tank of clinker.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitance type level meter for measuring the level of a stored material in a storage tank.

[0002]

2. Description of the Related Art There is a level meter for estimating the level of a medium when a medium is changed by forming a capacitor between a bottom plate of the reservoir and one electrode provided above the reservoir. .. FIG. 5 shows a configuration example of such a capacitance type level meter, in which the electrode 30 and the storage tank 31 are insulated from each other, a capacitor (electrostatic capacitance) is formed between them, and the presence or absence of the reservoir 32. Because the capacitance changes due to
The change detects the level of the reservoir.

FIG. 3 shows an exploded view of the measuring rod support portion. In the electrostatic capacitance type level meter, the measuring rod 1 which is one of the electrodes needs to be attached while being insulated. In FIG. 3, a measuring rod 1 is provided with insulating coatings 11 and 12 on a bulged portion 3 having a large diameter, insulated at the mouth of the outer cylinder 2, and inserted into the outer cylinder 2 so as not to come into contact with the outer cylinder 2. It is fixed. At the other end of the outer cylinder 2, the mounting end of the measuring rod 1 has a spring 14 and an insulator 15.
It is fixed by the nut 16 via. The outer cylinder 2 has a large-diameter terminal head portion 21, and is screwed and fixed to a mounting portion flange (not shown) by a flange mounting screw 22 provided on the outer cylinder 2. The measuring rod 1 is electrically connected to a printed circuit board 18 via a lead wire 17. 19 is a lid.

As described above, the measuring rod is fixed to the outer cylinder via the insulating coating. Conventionally, a Teflon tube coating 8 is used for this fixing portion as shown in FIG. When this capacitance level meter with Teflon tube insulation coating 8 is used to measure the level of the clinker storage tank in the cement calcination plant, the ambient temperature is high, and the coating 8 is broken due to friction etc. due to insufficient strength of Teflon. Caused insulation failure.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the structure of a support part for fixing a sensor part and an outer cylinder in a support part structure of a capacitance type level meter. The present invention relates to an improvement of a measuring rod support portion in which a large diameter portion is formed in the middle portion of a measuring rod of a capacitance level meter and the large diameter portion is fitted and fixed to an outer cylinder via an insulating material. .. As mentioned above, the Teflon tube coating is conventionally used for this insulating portion.

[0006]

According to the present invention, in order to solve the above problems, a sprayed alumina ceramics layer is formed as a lower layer and a silicon rubber layer is overlaid on the surface of a penetrating portion of a measuring rod into an outer cylinder. Providing a layer coating is a characteristic technical means. A second invention of the present invention is an alumina ceramics in which the large diameter portion of the intermediate portion of the measuring rod is formed with a step at a right angle, and is interposed between this step and the end face of the outer cylinder and the circumferential gap between the outer cylinder. It is characterized in that a two-layer insulating bush in which a silicon rubber layer is laminated on the insulating bush or alumina ceramics is provided. In this case, it is preferable that the insulating bush is divided into semicircles and the divided portions have a gap to facilitate mounting.

[0007]

In the support structure of the present invention, the coating has excellent heat resistance and insulation, and is highly durable, so that even when it is used in a clinker storage tank, insulation failure does not occur. In addition, if the large diameter part of the middle part of the measuring rod is formed with a step at a right angle and an insulating bush is provided between this step and the end face of the outer cylinder and in the circumferential gap between the outer cylinder, the structure is It is more durable and preferable because it does not require intensive concentration. In this case, if the insulating bush is divided into a semicircle and the divided portion has a gap, the support structure can be attached without disassembling the support structure.

[0008]

FIG. 1 shows the structure of an embodiment of the present invention.
The measuring rod 1 is provided with a tapered bulge 3 having a large diameter at a connecting portion with the outer cylinder 2, and this portion is covered. In this coating, a layer formed by spraying alumina ceramics 4 is formed on the surface of the penetrating portion of the measuring rod into the outer cylinder, and a silicone rubber layer 5 is formed thereon. The coating thickness is 1 mm for the alumina ceramic layer and 1 mm for the silicone rubber layer.

In FIG. 2, the large diameter portion 3 of the intermediate portion of the measuring rod 1 is formed with a right angle step, and a bush 6 is interposed between the measuring rod 1 and the outer cylinder 2. The bush 6 is an alumina ceramic insulating bush or a two-layer insulating bush in which a silicon rubber layer is laminated on the alumina ceramic.
FIG. 2B is a view on arrow AA of FIG. Figure 2
(C) is a shape in which the insulating bush 6 is divided into semicircular parts 7 and a gap is formed in the divided portion. Figure 2 (d)
Is a perspective view thereof. This is preferable because the mounting is easy.

[0010]

Since the present invention is constructed as described above,
It was installed in the clinker storage tank of the cement burning factory and has excellent durability, eliminating problems such as poor insulation.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment.

FIG. 2A is a side sectional view of another embodiment, and FIG.
It is an arrow line view, (c) AA arrow line view of other examples, and (d) perspective view.

FIG. 3 is an exploded view of an example.

FIG. 4 is a conventional side sectional view.

FIG. 5 is a diagram illustrating the principle of a capacitance level meter.

[Explanation of symbols]

1 Measuring Rod 2 Outer Cylinder 3 Bulge (Large Diameter Part) 4 Alumina Ceramics Layer 5 Silicon Rubber Layer 6 Bushing 7 Parts 11, 12 Insulation Coating 13 Screw 14 Spring 15 Insulation Ring 16 Nut 17 Conductor Wire 18 Printed Circuit Board

Front Page Continuation (72) Inventor Nobuyoshi Goto 12 Matsubara-cho, Kanda-cho, Kyoto-gun, Fukuoka Prefecture Mitsubishi Material Corporation Kyushu Works Kanda Plant

Claims (3)

[Claims] 1. A measuring rod support portion in which a large diameter portion is formed in an intermediate portion of a measuring rod of a capacitance type level meter, and the large diameter portion is fitted and fixed to an outer cylinder through an insulating material. The structure of the support part of the measuring rod of the electrostatic capacitance type level meter, characterized in that the surface of the penetrating part of the outer cylinder has a sprayed alumina ceramics layer as the lower layer and a silicon rubber layer as the upper layer. .. 2. An alumina ceramic insulating bush or alumina ceramics, wherein a large diameter portion of the intermediate portion of the measuring rod is formed with a step at a right angle, and is interposed between the step and the end face of the outer cylinder and the circumferential gap between the outer cylinder. A supporting structure for a measuring rod of a capacitance type level meter, characterized in that a two-layer insulating bush having a silicone rubber layer laminated thereon is provided. 3. The insulating bush is divided into semicircles,
The support portion structure for the measuring rod of the electrostatic capacitance level meter according to claim 2, wherein the divided portion has a gap.