JPS6121666B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a regenerative electric heater used in a heater or the like.

Conventional Structure and Problems The conventional latent heat storage method has a structure in which a latent heat storage material is stored in a heat storage tank or a heat storage container, and a heating source such as an electric heater is embedded in the latent heat storage material. In this method, heat storage rate, heat release rate, and heat storage efficiency are problems, and to solve these problems, measures have been taken such as using heat exchangers, fins, heat media, etc., or encapsulating latent heat storage materials. On the other hand, as a local heater for the human body, etc., electric heaters buried in heat insulating materials are commonly used, but these conventional electric heaters require a power cord at all times, and the spatial usage range of the heater is was limited to the length of its power cord. In recent years, there has been a demand for heaters that can continue heating for a certain period of time even after the power to the electric heater is turned off.
This requires the development of a heat storage type electric heater, but in order to use the conventional latent heat storage method mentioned above as a heat storage method for such a heater, there are costs, weight,
There were problems with flexibility depending on the purpose of use.

OBJECTS OF THE INVENTION An object of the present invention is to provide an electric heater for use in heaters, heat insulators, etc. that uses a latent heat storage method and has high heat storage efficiency, low cost, light weight, and flexibility.

Structure of the Invention The basic structure of the present invention is that a sheet heating element having a heat generating part and a non-heat generating part has a container for storing a latent heat storage material in close contact with both sides of the heat generating part.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a latent heat storage type electric heater according to an embodiment of the present invention, in which 10 is a planar heating element, which has a heat generating part 11 and a non-heat generating part 12. The heat generating part 11 is made of a thick copper alloy whose surface is electrically insulated.
It is a 0.5mm plate. The non-heat generating part 12 is made of nylon net cloth. In order to connect the heat generating parts 11 in series, terminals are formed at both ends of the copper alloy plates, and connecting wires 15 are embedded in the nylon mesh cloth to connect the copper alloy plates. The power cord 14 can be connected to a power outlet from the first and last terminals of the series-connected copper alloy plates. The total power consumption is 80watt. The heat generating part 11 has 9 sides of 5 x 5 cm, and the non-heat generating part 12
is 2cm wide. Reference numeral 13 denotes a container for storing the latent heat storage material, which is made of a stainless steel film with a thickness of 0.2 mm, and is made into a flat box-shaped container by welding. The container dimensions are 0.5 x 5 x 5 cm. The latent heat storage material used here was sodium acetate trihydrate containing 1% by weight of sodium pyrophosphate decahydrate as a supercooling inhibitor. 16 g of this was weighed and filled in a molten state into 18 containers 13, which were adhered to both sides of the heat generating part with an adhesive having good thermal conductivity to form a finished product.

The melting point of this latent heat storage material is 58℃, the freezing point is 53℃,
The latent heat of melting and solidification is 60cal/g, and the specific heat of solid is 0.3c.
The specific heat in al/g°C liquid is 0.7 cal/g.

Here, the outside temperature is 20℃, and the heat storage temperature level is 65℃.
When set to
The total amount is 1.22kcal, and since 18 containers 13 are used in total, the total is 22.0kcal. It takes about 20 minutes to store this amount of heat in an insulated state.

Next, this regenerative electric heater can be used as a heater for an electric chiyotsuki, which is one type of local heater. As a result of embedding this heat storage type electric heater in the insulation material of the Chiyotsuki, when the power is turned on, the Chiyotsuki enters the heat retention state (28W heat dissipation), and the temperature of the latent heat storage material reaches the set temperature within 30 minutes after the power is turned on. 65℃
is reached, and even if you turn off the power at this point, the subsequent
It was able to maintain heat retention (28W heat dissipation) for 45 minutes.

Conventional electric chiyotsuki (heater power is for comparison)
28W), the power input is kept warm (28W heat dissipation)
However, when the power is cut off, the heat retention function is rapidly lost. In contrast, the thermal storage electric heater of the present invention (heater power 80W, significant heat capacity 22kcal)
By using this, the heat retention function can be maintained even after the power is turned off. In other words, cordless cords can be achieved. Furthermore, since the non-heat generating part is flexible, it fits around your back when worn.

FIG. 2 shows a latent heat storage type electric heater according to a second embodiment of the present invention, in which the same sheet heating element 10 as used in the first embodiment was used.
The container 13 that stores the latent heat storage material is made of a laminate film (polyethylene (0.1 mm) - stainless steel (0.1 mm)
mm)), two 5.5 x 5.5 cm films with a polyethylene inner side and a width of 0.5 cm.
It was made by hot-pressing the four sides together. Eighteen of the same materials were made, and 8 g of the latent heat storage material used in the first example was weighed and filled in a molten state.
Each was adhered to both sides of the heat generating part using an adhesive with good thermal conductivity to create a finished product.

Here, the outside temperature is 20℃, and the heat storage temperature level is 65℃.
When set to , the heat storage capacity for one container is
The sum of latent heat is 0.48kcal and sensible heat is 0.13kcal.
The total amount is 0.61kcal, and since 18 containers are used in total, the total is 11.0kcal. It takes about 10 minutes to store this amount of heat in an adiabatic state.

Next, this regenerative electric heater can be used as a heater for an electric chiyotsuki, which is one type of local heater. As a result of burying this heat storage type electric heater in the heat insulating material of the Chiyotsuki, when the power is turned on, the Chiyotsuki enters the heat retention state (14W heat dissipation), and the temperature of the latent heat storage material reaches the set temperature within 15 minutes after the power is turned on. 65℃
reached and even if I cut off the power at this point, after that 25
It was possible to maintain heat retention (14W heat dissipation) for minutes.

Conventional electric chiyotsuki (heater power is for comparison)
(14W) can maintain heat retention (14W heat dissipation) when the power is input, but it quickly loses its heat retention function when the power is turned off. In contrast, the heat storage electric heater of the present invention (heater power 80W, heat storage capacity
11kcal), the heat retention function can be maintained even after the power is turned off. In other words, the power cord can be made cordless. Furthermore, since the non-heat generating part is flexible, it fits around your back when worn.

As shown in the above embodiments, the container B is box-shaped or bag-shaped made of metal film, or box-shaped or bag-shaped made of laminate film. The size of the container 13 is determined by the required heat storage (input) time, heat storage capacity, unit area of the planar heating element, power consumption per unit time, and thermal conductivity of the latent heat storage material. However, considering overall flexibility, it is desirable that each container be small, and the number of containers may be adjusted according to the desired heat storage capacity.

Possible methods for bringing the sheet heating element 10 and the container 13 into close contact include adhesives, heat fusion, or welding, but an appropriate method may be selected depending on the materials of the sheet heating element 10 and the container 13. .

Furthermore, since the non-heat generating portion 12 is provided to provide flexibility as a whole, it must be made of a material that has strength depending on the usage condition.

Effects of the Invention As described above, the heat storage type electric heater of the present invention is an electric heater with high heat storage efficiency and high flexibility, and also enables temporary cordless conversion of conventional heaters, heat insulators, etc. It is.

[Brief explanation of the drawing]

1 and 2 are schematic perspective views of a regenerative electric heater according to an embodiment of the present invention. 10... Planar heating element, 11... Heat generating part, 12...
Non-heat generating part, 13... Container.

Claims (1)

[Scope of Claims] 1. A sheet heating element is constructed from a heating part connected to a power source and a flexible non-heating part, and a container containing a latent heat storage material is tightly attached to both sides of the heating part of this sheet heating element. A regenerative electric heater. 2. The heat storage type electric heater according to claim 1, wherein the container for storing the heat storage material is formed of a metal film. 3. The regenerative electric heater according to claim 1, wherein the container for storing the heat storage material is made of a laminate of at least two films made of different materials, and at least one of which is made of a metal film.