JPS63206486A - Corrosion preventive device for hot water storage tank - Google Patents

Abstract

PURPOSE:To prevent adhesion or deposition of scale to the circumference of an electrode wire or electrode plug by deforming and restoring a thermosensitive deforming member consisting of a shape memory alloy disposed around the electrode plug according to a temp. change. CONSTITUTION:The electrode plug 11 is mounted on the side wall of a hot water storage tank 10 of a hot water supplier and the electrode wire 12 is projected to the inside of the hot water storage tank 10. The thermosensitive deforming member 18 consisting of the shape memory alloy is mounted on an end part 16 of a metallic member 14 of said plug 11 where said end faces the inside of the tank 10. The member 18 has plural vane pieces 19. The vane pieces 19 take the position along the wire 12 when the temp. of the hot water is low. Said pieces take the position parting from the wire 12 as shown by an alternate long and two short dashes line at a high temp. An insulating member 20 to prevent the contact of the vane pieces 19 with the wire 12 is provided on the top end of the wire 12. The member 18 of this hot water supplier repeats the action of deformation and restoration only by the temp. change of the cold and heat of the hot water in the tank 10, thereby preventing the adhesion and deposition of the scale (b).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a corrosion protection device for a hot water storage tank, which is disposed inside a hot water storage tank of an electric water heater, oil water heater, etc., and prevents corrosion of the inner surface of the hot water storage tank. .

Conventional Technology Generally speaking, the hot water storage tank of a water heater is prone to corrosion, so as shown in FIG.
is attached. The electrolytic protection device 2 is made up of an electrode plug 3 and an electrode wire 4, for example, as shown in FIG. 6, and the electrode plug 3 is made up of an insulating member 5 and a metal member 6 made of iron or the like surrounding it. A portion 7 of the metal member 6 faces into the hot water storage tank 1. Note that the hot water storage tank 1 has a structure in which a glass lining 8 is provided on the inner surface. The anticorrosion device 2 equipped with the electrode wire 4 is placed in front of the hot water storage tank 1 in this way, and a positive potential is applied to the electrode wire 4.
It is well known that corrosion of the hot water storage tank 1 that comes into contact with water can be prevented by applying a negative potential to the hot water storage tank 1 (Jikko Kosho 5).
5-18376).

Problems to be Solved by the Invention However, in the conventional one, the metal member 6 of the electrode plug 3
Since the part 7 facing the hot water storage tank 1 does not have the glass lining 8 coating, a part of the anticorrosion current flows through this metal member 6 as a short circuit, and therefore the Mg contained in the hot water is
Positive ion components such as , C&, and Sl precipitate as scale a, and adhere to a portion 7 of the metal member 6 in a concentrated manner. Then, over a long period of time, this mountain of scale a covers the entire electrode wire 4, eventually blocking the anti-corrosion current and causing the problem that corrosion protection cannot be maintained.

In view of the above problems, the present invention provides an electrolytic protection device that prevents scale from adhering to electrode wires, no matter how strong the water quality is.

Means for Solving the Problems In order to solve the above-mentioned problems, the corrosion protection device for a hot water storage tank of the present invention has a temperature-sensitive deformable member made of a shape memory alloy arranged around the electrode plug, so that the temperature-sensitive deformable member made of a shape-memory alloy is arranged around the electrode plug, and the temperature-sensitive deformable member made of a shape-memory alloy is arranged around the electrode plug. The temperature-sensitive deformable member is deformed and restored accordingly.

Function: In the corrosion protection device for a hot water storage tank of the present invention, when the hot water temperature changes, that is, when the hot water temperature is low, the temperature-sensitive deformable member made of a shape memory alloy is in a state along the electrode wire, and when the hot water temperature is high, the temperature-sensitive deformable member is in a state along the electrode wire. Since the water temperature changes each time hot water is supplied, the temperature-sensitive deformable member repeats deformation and restoration operations, thus preventing scale from adhering to or accumulating around the electrode wire or electrode plug. It happens.

EXAMPLE Hereinafter, a corrosion protection device for a hot water storage tank of a water heater according to an example of the present invention will be described with reference to FIGS. 1 and 2.

In Figure 1, 1o is the hot water storage tank of the water heater, the electrode plug 11 is attached to the side wall, and the electrode wire 12 is connected to the hot water storage tank 1.
It protrudes inside 0. Specifically, the electrode plug 11 includes an insulating member 13 that holds the electrode wire 12, and this insulating member 1.
A metal member 14 made of iron that surrounds 3 and has a threaded portion on the outside.
holder 15 attached to the hot water storage tank 10
It is attached by screwing to the holder and can be removed for maintenance. An end 16 of the metal member 14 of the electrode plug 11 faces into the hot water storage tank 1o. A glass lining 17 is provided on the inner surface of the hot water storage tank 1o.

The characteristic configuration of this embodiment is as follows.

That is, a temperature-sensitive deformable member 18 made of a shape memory alloy is attached to the end 16 of the metal member 14 of the electrode plug 11 facing into the hot water storage tank 1o. As shown in FIGS. 1 and 2, this temperature-sensitive deformable member 18 has a plurality of wing pieces 19,
When the temperature of the hot water is low, the blade 19 takes a position along the electrode wire 12, and when the water temperature is high, the shape is memorized so that it takes a position away from the electrode wire 12, as shown by the two-dot chain line in FIG. Note that a temperature-sensitive deformable member 1 is provided at the tip of the electrode wire 12.
An insulating member 20j is provided to prevent the wing pieces 19 of No. 8 from coming into contact with the electrode wire 12.

In the above configuration, the water heater repeatedly deforms and restores itself only due to temperature changes in the cold water in the hot water storage tank 1o, thereby preventing scale adhesion and accumulation as shown in part b. Therefore, over a long period of time, the electrode plug 11 and the electrode wire 1
The anti-corrosion current is no longer blocked by the scale b around 2, and the anti-corrosion performance can be maintained at all times. Incidentally, the insulating member 2° can also prevent the concentration of the anti-corrosion current at the tip.

In this embodiment, a plate-shaped coil is used, but the same effect can be obtained by utilizing the deformation and expansion/contraction of a linear coil as shown in FIG. In this case, the temperature-sensitive deformable member 18
expands when cold and contracts when hot, causing the insulating member 20 to move repeatedly each time.

Effects of the Invention As is clear from the above description of the embodiments, the present invention can expect the following effects by providing a temperature-sensitive deformable member made of a shape memory alloy around the entire electrode plug.

(1) There is no possibility that the hot water storage tank will be corroded or damaged unnoticed by the user, which will eventually lead to accidents such as water leakage.

(Important) Eliminates the need for troublesome maintenance work such as removing scale by removing the anti-corrosion device.

(3) When cold, the temperature-sensitive deformable member is in an undeformed state and does not interfere with the workability of assembling the cathodic protection device into the hot water storage tank.

(4) Since the temperature-sensitive deformable member deforms when heated, it does not impede the flow of anticorrosion current from the electrode wire. (Anti-corrosion current is especially required at high temperatures.)

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional configuration diagram of a corrosion protection device for a hot water storage tank according to an embodiment of the present invention, Fig. 2 is a perspective view of a temperature-sensitive deformable member of the corrosion protection device of the same embodiment when it is cold, and Fig. 3 is a diagram showing another embodiment. FIG. 4 is an overall cross-sectional view of a conventional hot water storage tank, and FIG. 6 is a cross-sectional view of the conventional corrosion preventive device. 6... Temperature-sensitive deformable member, 10... Hot water storage tank, 11... Electrode plug, 12... Electrode wire. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 6 --- Temperature-sensitive sleeve-shaped insulation material 10-1000 tank Figure 2 Figure 3 Figure 4 ↑ Figure 5

Claims (1)

[Claims] A corrosion protection device for a hot water storage tank in which a temperature-sensitive deformable member made of a shape memory alloy is disposed around an electrode plug, and the temperature-sensitive deformable member deforms and restores its shape in response to changes in hot water temperature.