JPS59158838A - Burn preventing apparatus in water heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a burn prevention device for a water heater, and more particularly to a technique for simplifying and improving the structure of the device while ensuring reliable burn prevention.

[Background Art] Conventionally, as shown in FIG. 1, a burn prevention device for a water heater has a first positive temperature coefficient thermistor (7) that controls the temperature of hot water by 30 degrees.
The first positive temperature coefficient thermistor (8) is placed in parallel with the first positive coefficient thermistor (7) as a hole length circuit to constantly set the hot water temperature to maintain it at about 60°C to 50°C.
When the temperature exceeds 0℃, the current to the heater (9)' is stopped and at the same time the pump (10) for supplying water to the hot water tank (1)'
scalding prevention means for stopping the electric current to ', stopping further heating by the heater (9)' and preventing boiling water from being released even if the faucet fitting (11)' is opened; There is a method for preventing dry heating by attaching a temperature fuse (12) to the hot water tank (1)'. However, although these double and triple safety measures provide high safety, they have the problem of high cost, high probability of failure, and many unsettling aspects.

[Purpose of the invention]

An object of the present invention is to greatly simplify the configuration while being able to reliably prevent burns through a rational configuration.

[Disclosure of the invention]

The present invention provides a valve hole (3) in the middle of the hot water supply route to the hot water supply port (2) from which the hot water supplied from the hot water tank (1) is spouted,
A valve (4) capable of closing the valve hole (3) is provided,
The valve (4) is made of a shape memory alloy (5) that displaces significantly when a certain temperature is reached due to temperature changes.
This relates to a burn prevention device for a water heater which is supported by a water heater, and by configuring it in this way, the above object can be achieved.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In Figure 2, the hot water tank (1) has a check valve (13).
Connect the city water supply pipe (14) through the hot water tank (1
), and hot water is spouted from a shower nozzle (16) serving as a hot water supply port (2) provided at the tip of a hot water supply pipe (15) connected to a hot water tank (1). It is made possible to do so. Hot water pipe (15)
is equipped with a faucet fitting (11).
By opening and closing the shower nozzle (16), hot water can be spouted from the shower nozzle (16) and hot water can be stopped. In the figure, the pump for pumping is omitted. As shown in the figure, the connection point between the hot water tank (1) and the hot water supply pipe (15) is a conical opening, and this point is a valve hole (3).

A valve (4) that closes the valve hole (3) is supported by a wire-shaped shape memory alloy (5) that faces the middle of the hot water supply path. The shape memory alloy (5) is attached to the side wall (17) of the hot water tank (1) as a fixed foot (6).

The shape memory base metal (5) undergoes a large reversible displacement when a specific temperature is reached due to temperature changes. For example, when a specific (transformation) temperature such as 50°C is exceeded, martensitic transformation occurs and the shape becomes a specific shape (elongation). shape), and the temperature at 40°C
It reversibly deforms to its original shape (shrinking shape) when the temperature drops below a certain temperature, such as nickel, titanium, etc. By adding other elements, the transformation temperature can be set. Moreover, when it transforms into a specific shape, the force exerted is about 200 times or more compared to the force caused by expansion and contraction of a bimetal element of the same size. In the example, φ3 "Phoenix Alloy NT001" (titanium-nickel alloy wire) was used, and a SUS304 sphere was used as the valve element (4). Moreover, the hot water supply pipe (15) has a diameter of 10 mm.

According to this configuration, when the temperature of the hot water exceeds, for example, about 50°C, the wire-like shape memory alloy (5) deforms into a specific elongated shape of a certain length, and the valve element (4) is inserted into the valve hole (3). Press the button to stop hot water supply. When the temperature of the hot water drops below, for example, about 40° C., the shape memory alloy (5) deforms to its original specific bent shape and opens the valve hole (3). Benko (4)
If the fixing part (6) is located on the source side, the internal pressure can enhance the closing effect. Although a shape memory alloy (5) is used that is reversible, it may also be one that deforms irreversibly. Bend the wire of the shape memory base metal (5).

Figure 3 shows another embodiment, with a valve hole (3) and a valve element (4).
is formed in the valve hole (15) before hot water is supplied, and the fixed position of the shape memory alloy (5) is such that when the shape memory alloy (5) is fully extended, the valve element (4) closes the valve hole (3). Of course, the distance should be set at a distance sufficient for this purpose. In this embodiment, a shape memory base metal (5) that performs reversible deformation is preferable.

Figure 4 shows yet another example, which is implemented in a private parts cleaning device that cleans the private parts of the human body with hot water, and is heated to the installation temperature of 40°C using a thermostat (19) and a sheathed heater (9). Control and access and faucet fittings (11)
When opened, hot water comes out of the shower nozzle (16) due to water pressure. If the temperature inside the hot water tank (1) rises to 50°C or higher due to a problem such as a failure of the thermostat (19),
The shape-memory alloy (5) exhibits the above-mentioned shape memory effect and instantly stretches to its original shape, so that the valve element (4) at the tip of the shape-memory alloy (5) forms a conical valve hole (3). ), the waterway is blocked and hot water does not come out of the shower nozzle (16). Note that this example also uses a shape memory alloy (
5) is easier to use if it deforms reversibly, but it may also deform irreversibly. In such a case, remove the inspection port (18) of the hot water tank (1) after repairing the malfunctioning part. , bend the wire of the shape memory base (5) by hand again to fit the valve hole (
3) Just open it. In the figure (20) is a water tank, (21)
is a submersible pump, and (22) is a toilet bowl.

〔Effect of the invention〕

To put it simply, in the present invention, the valve is supported on a fixed part in the hot water supply path using a shape memory alloy that displaces significantly when a certain temperature is reached due to temperature changes. It has the advantage of being able to greatly simplify its configuration and increase reliability by blocking the hot water supply path when it is significantly displaced due to temperature changes, that is, when the temperature exceeds a certain level, thereby ensuring the prevention of burns. be.

[Brief explanation of the drawing]

Fig. 1 is a hot water supply system diagram of a conventional example, Fig. 2 is a hot water supply system diagram of an embodiment of the present invention, Fig. 3 is a partially enlarged cross-sectional view of another embodiment of the improvement, and Fig. 4 is a further improvement. is a hot water supply system diagram of the example, (1) is a hot water tank, (2) is a hot water supply port, (3) is a valve hole, (4) is a valve, (5) is a shape memory alloy, and (6) is a hot water supply system diagram. It is a fixed part. Deputy Burial Officer Masashi Choshichi Ishida

Claims (1)

[Claims] (1) A valve hole is provided in the middle of the hot water supply route to the hot water inlet that spouts hot water from the hot water tank, and a valve that can block the valve hole is provided, and it displaces significantly when a certain temperature is reached due to temperature changes. A burn prevention device for a water heater that includes a shape memory alloy valve that is supported on a fixed part in the hot water supply path.