JPH0432518B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) This invention relates to a regenerative electric heater used as a local heater or the like.

(Prior Art) Recently, a heat storage electric heater that uses a latent heat storage material and is convenient to carry has been developed. Such a heat storage type electric heater has a latent heat storage material sealed in a sealed container, heats this latent heat storage material with a heating element and melts it to store heat, and then stops the heating by the heating element and stores the latent heat heat storage material. The material is gradually solidified and the latent heat of fusion released during this process is used as heating heat.

As a latent heat storage material, clathrate hydrates are often used due to their suitable freezing point (melting point) temperature and cost advantages, and are especially used in heat storage electric heaters for the human body (Chiyotsuki, Matsuto, etc.). It is considered optimal to use hydrated sodium acetate due to the compatibility between human body temperature and freezing point (melting point) temperature.

By the way, in this type of latent heat storage material, even if the latent heat storage material reaches the freezing point due to the supercooling phenomenon, it does not solidify and remains in a liquid state, and as a result, the release of latent heat is not achieved. As seen in JP-A-60-77389 and JP-A-60-77391, a supercooling prevention material is added to the latent heat storage material to prevent the occurrence of supercooling.

On the other hand, in a regenerative electric heater that uses such a latent heat storage material, first, an external power source (commercial power source) is used to energize the heating element to generate heat, and this heat heats the latent heat storage material and stores heat. Later, this regenerative electric heater was released from an external power source and used outdoors. Conventionally, when a thermal storage heater is disconnected from an external power source,
In other words, when the heating element stops generating heat, the latent heat storage material immediately starts releasing latent heat.

However, in the conventional configuration in which the latent heat storage material releases latent heat immediately after being released from the external power source, after storing heat in the latent heat storage material,
If the product is used after a certain period of time, the latent heat will be wasted before that time, which shortens the time it can be used effectively, reducing usability and causing economic loss. There was a problem.

Therefore, as filed as Utility Model Application No. 61-22070, the present applicant sealed the latent heat storage material in a sealed container without adding a supercooling inhibitor, and as shown in FIG. to cause a supercooling phenomenon, apply a voltage to the latent heat storage material at any time by operating a switch to apply a stimulus, and this stimulation releases the supercooling of the latent heat storage material and causes it to release latent heat. We have developed a regenerative electric heater that can collect heat when needed.

(Problems to be solved by the invention) However, in the above-mentioned regenerative electric heater,
When the switch is operated, all supercooling of the latent heat storage agent is canceled, and therefore latent heat is released all at once.As a result, a higher amount of heat than necessary is released in a short period of time, and the appropriate temperature is not maintained for a long time. There was a problem in that it became difficult to hold and collect heat, reducing usability. If the outer periphery of the sealed container containing the latent heat storage material is covered with a heat insulating material, it is possible to suppress the radiation of heat to the outside and extend the heating time to some extent. Not only is this bulky, which is economically disadvantageous, but also a portion of the heat is absorbed by the heat insulating material, reducing efficiency. This invention aims to solve these problems.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes a plurality of sealed containers each containing a latent heat storage material that causes a supercooling phenomenon, and Electrodes for applying voltage to the latent heat storage material are provided, and energizing means capable of energizing these electrodes in stages with a time lag is provided.

(Function) After the latent heat storage material sealed in each sealed container has caused a supercooling phenomenon, when a current is applied to the electrodes of the sealed container in a stepwise manner with a time lag using an energizing means, a voltage is applied. Accordingly, the supercooling of the latent heat storage material in the sealed container is released in stages, and the latent heat is released in stages.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

In the figure, 1 is a planar heating element, and this heating element 1 has a plurality of ribbon heaters 2 arranged vertically and horizontally, and these ribbon heaters 2 are sandwiched between two polyethylene films and bonded together by thermocompression to form a certain area. It is configured in a planar shape with Ribbon heaters 2 in each row are connected in series via lead wires 3, these lead wires 3 are connected in parallel to power wires 4, 4, and these power wires 4, 4 are connected to an external power source 5. It is removably connected.

On the upper surface side and the lower surface side of the heating element 1, first, second, and
Third and fourth heat storage bags 6a, 6b, 6c, 6d
are provided, and these heat storage bags 6a, 6b, 6
c and 6d, as shown in FIG. 3, a pair of metal foil/plastic laminate films 9, 9 made by covering both sides of a conductive metal foil 7 with plastic films 8, 8 are superimposed, and the ribbon heater 2 is placed between them. A sealed container 10 is constructed in a portion corresponding to the arrangement portion of the laminate film 9, and the laminate films 9 are integrated by, for example, thermocompression bonding, except for the portion of the sealed container 10. A latent heat storage material 11 is enclosed in each sealed container 10. This latent heat storage material 11 is, for example, sodium acetate hydrate (NaCH ₃ COO・3H ₂ O), which is solid at room temperature.
It has a melting point of 58℃ and has the property of causing supercooling when the temperature drops.

Each sealed container 10... has openings 12, 12 formed by cutting out a part of the plastic films 8, 8 of the laminate films 9, 9 on the upper and lower inner surfaces thereof.
are formed, and through these openings 12, 12, parts of the metal foils 7, 7 are exposed so as to face each other with the latent heat storage material 11 in between, and in these exposed parts, electrodes 13, 13 are exposed.
is configured. Then, energizing wires 14a, 14b, 14c, 14d are connected independently from one end of one metal foil 7 of each of the first, second, third, and fourth heat storage bags 6a, 6b, 6c, and 6d. Similarly, the other metal foil 7... a common current-carrying wire 15 from the other end.
are respectively derived, and each of the above-mentioned current-carrying wires 14a, 14
The self-returning type 1st,
Second, third, fourth switches 16a, 16b, 1
These switches 16a, 16b, 16c, and 16d are connected in common to the energizing wire 15, and in the middle of the energizing wire 15, for example, there is a main body (not shown) of the present regenerative electric heater. ) is interposed with an internal power source 17 such as a dry cell battery.

Next, we will discuss the effect.

First, the external power supply 5 energizes each ribbon heater 2 of the heating element 1 to heat the latent heat storage material 11 in each sealed container 10. In response to this heating, as shown in FIG.
℃), the temperature stops rising and starts melting, and this melting stores heat. When everything melts, heat storage is completed, and the temperature of the latent heat storage material 11 increases again, so at this point, the ribbon Heater 2
Turn off the power to... Along with this, latent heat storage material 1
1... lowers the temperature while releasing sensible heat, but
Due to the supercooling phenomenon, it does not solidify even when it reaches the freezing point (58℃), and the temperature drops while retaining latent heat.

Therefore, when actually using the regenerative electric heater, first the first switch 16a is temporarily closed. In response to this, the metal foils 7, 7 of the first heat storage bag 6a are energized, and a voltage is applied between the electrodes 13, 13 of each sealed container 10 in this heat storage bag 6a, thereby causing the latent heat storage material 11... is stimulated by an electric shock, and this stimulation releases the supercooling of the latent heat storage material 11 and rapidly solidifies, the temperature rises to the freezing point, and then the latent heat is gradually released, and this heat is It diffuses into each part of the regenerative electric heater through the metal foils 7, 7.

When the first switch 16a is operated in this way, the supercooling of each latent heat storage material 11 in the first heat storage bag 6a is canceled and these latent heat storage materials 1
1. Latent heat is released from... Thereafter, when the second switch 16b is closed, the supercooling of the latent heat storage materials 11 in the second heat storage bag 6b is similarly released, and the latent heat is released from the latent heat storage materials 11. Furthermore, the third and fourth switches 1
When 6c and 16d are closed step by step, the third,
The supercooling of each latent heat storage material 11 in the fourth stage is released in stages, and the latent heat is released in stages.

In this way, each heat storage bag 6a, 6b, 6c,
It is possible to release latent heat in stages from the latent heat storage material 11 every 6 d, thereby maintaining the amount of heat at an appropriate temperature, and extending the overall latent heat release time, making it easier to use. In addition, there is no need for a heat insulating material covering the outer periphery of the sealed container 10, and increased costs and wasteful absorption of heat can be eliminated.

On the other hand, although the latent heat storage material 11 is solid at room temperature, the latent heat storage material 11 is subdivided into a plurality of sealed containers 10, so that the heat storage electric heater as a whole has sufficient capacity. Flexibility occurs,
It can be conveniently handled. Then, the laminate film 9, which constitutes the sealed container 10...
Since the electrodes 13 of each sealed container 10 are constructed using the metal foils 7, 7 of No. 9, the structure is simple and advantageous in terms of assembly and cost.

In addition, if you operate each switch step by step with a time lag, if you manually operate it,
For example, a timer may be used, or both may be used together. Further, the sealed container is not limited to the laminate film, but can be constructed using other materials, and furthermore, it is also possible to incorporate a heating element for heating the latent heat storage material inside the sealed container.

[Effects of the Invention] As explained above, according to the present invention, the release of latent heat can be started in stages with a time lag, and therefore the amount of heat can be maintained at an appropriate temperature, and the release of latent heat can be started in stages. The release time can be extended, which has the effect of improving usability.

[Brief explanation of drawings]

FIG. 1 is an overall plan view showing an embodiment of the present invention, FIG. 2 is a sectional view, FIG. 3 is a partial sectional view, and FIG. 4 is a characteristic curve diagram of the latent heat storage material. FIG. 5 is a characteristic curve diagram of a latent heat storage material according to the prior art. 1... Heating element, 7... Metal foil, 8... Plastic film, 9... Laminate film, 10
... sealed container, 11 ... latent heat storage material, 13 ... electrode.

Claims (1)

[Scope of Claims] 1. A plurality of sealed containers, a latent heat storage material that causes a supercooling phenomenon sealed in these sealed containers, a heating element that heats these latent heat storage materials, and 1. A regenerative electric heater comprising electrodes for applying a voltage to a latent heat storage material, and energizing means capable of energizing these electrodes in stages with a time lag. 2. The hermetically sealed container is made of a metal foil/plastic laminate film, and a part of the metal foil of the laminate film is exposed inside the sealed container and used as an electrode. Regenerative electric heater.