JPH113770A - Heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat exchange efficiency, to make setting of temperature optional and to homogenize the temperature distribution by spirally winding a metal plate, electrically connecting the winding start and the winding end to form a heating unit body, and stacking the heating unit bodies in the axial direction of a container to constitute a heat exchange element and arranging it. SOLUTION: A heating unit body 201, constituting a heat exchange element 203, is constituted by spirally winding a stainless steel plate, and electrically connecting a winding start and winding end with a lead wire 202, and the heating unit bodies 201 are stacked in the axial direction of a container 101 to constitute the heat exchange element 203. When a switch is turned on, a high-frequency power supply means and a liquid-transporting means start operation, and a liquid is passed through the container 101. At the same time, high-frequency power is supplied from the high-frequency power supply means, and a heating coil generates high-frequency magnetic field. High-frequency magnetic field is interlinked with the heat exchange element 203, eddy current flows, Joule heat is generated, and heat from induced heating is generated uniformly from the whole surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for heating a liquid such as water or petroleum.

[0002]

2. Description of the Related Art Conventionally, an instant water heater is used to raise the temperature of water. In addition, an oil heater that utilizes gas combustion is used as an evaporator for evaporating oil as a fuel.

[0003]

However, in conventional heating devices such as an instantaneous water heater and a vaporizer using gas, it is necessary to lower the temperature of the heating unit in order to avoid local boiling. There are problems such as a low heat exchange efficiency, difficulty in raising the temperature to a high temperature near the boiling point, and a non-uniform temperature distribution.

That is, in the conventional heating device, particularly when the object to be heated is high in viscosity such as petroleum, local boiling occurs and the superheated portion is burnt. Therefore, it is necessary to lower the temperature of the heating unit, which lowers the heat exchange efficiency. Further, it is difficult to raise the temperature to a high temperature near the boiling point. Further, flame combustion by gas involves a large amount of heat escaping to the outside and low thermal efficiency. Further, since the heating by the gas is performed from the outside of the pipe, the temperature of the liquid flowing outside the pipe is inevitably increased.

[0005]

SUMMARY OF THE INVENTION The present invention provides a heating element comprising a metal plate formed in a spiral shape and a heating unit having a winding start and a winding end electrically connected to each other, which are laminated in the axial direction. Induction heating by a heating coil wound outside,
The heating device has a high heat exchange efficiency by heating a liquid or a gas flowing inside the heating element, has a free temperature setting, and has a uniform temperature distribution.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention described in claim 1 is a heat generating apparatus in which a metal plate is formed in a spiral shape in a container, and a heat generating unit in which a winding start and a winding end are electrically connected is laminated. A heating device that accommodates the body and heats the heating element by a heating coil wound around the outside of the container to raise the temperature of a liquid or gas flowing inside the heating element is realized.

According to a second aspect of the present invention, a heating device having a heat exchange element which can increase a contact area with a liquid by using a corrugated metal plate, and particularly enhances heat exchange efficiency is realized. ing.

According to a third aspect of the present invention, the heat exchange element comprises a plurality of metal rings arranged concentrically, and the innermost metal ring is made of a magnetic metal to increase the temperature of the liquid flowing through the center. As a result, a heating device having a uniform temperature distribution is realized.

[0009]

Embodiments of the present invention will be described below. FIG.
FIG. 2 is a block diagram showing the configuration of the present embodiment. 101
Is a cylindrical container having pipes through which liquid flows at the top and bottom, and houses therein a heat exchange element 203 shown in FIG. Also, on the outside of the container 101,
A heating coil 102 for generating a high-frequency magnetic field is wound. The heating coil 102 includes a high-frequency power supply unit 103 configured by an inverter circuit or the like that supplies high-frequency power.
Is supplied with high frequency power. Also 104
Is a liquid transfer means disposed in a liquid transfer path constituted by the container 101 and pipes connected to upper and lower portions of the container 101. The liquid transfer means 104 is constituted by a pump.

FIG. 2 shows the structure of the heat generating unit 201 constituting the heat exchange element 203. Heating unit 201
As shown in FIG. 2A, a stainless steel plate is spirally wound and is electrically connected by lead wires 202 at the start and end of winding. Further, as shown in FIG. 2B, the heating unit 201 is
Are stacked in the axial direction to constitute the heat exchange element 203. The central portion of the heat exchange element 203 is hollow, and when housed in the container 101, the liquid flows through this central portion. The heat exchange element 203 of this embodiment can be made of either magnetic stainless steel or non-magnetic stainless steel, or a metal plate other than stainless steel.

The operation of the embodiment will be described below. When a switch (not shown) is turned on, the high-frequency power supply unit 103 and the liquid transfer unit 104 start operating, and the liquid passes through the container 101. At the same time, the heating coil 1 receives the supply of the high-frequency power from the high-frequency power supply means 103.
02 generates a high-frequency magnetic field. This high-frequency magnetic field links with the heat exchange element 203 housed in the container 101,
The heat exchange element 203 is induction heated. That is, in the heat exchange element 203, an eddy current flows due to the interlinking of the high-frequency magnetic field, and Joule heat is generated. The heat generated by the induction heating is uniformly generated from the entire surface of the heat exchange element 203. The liquid flowing through the heat exchange element 203 is heated to a predetermined temperature when passing through the container 101 due to the heat generation. Thus, in this embodiment,
Since the heat exchange element 203 is configured to directly exchange heat with the liquid, and the induction heating by the high-frequency magnetic field generated by the heating coil 102 is used, the heating efficiency is very high.

At this time, in this embodiment, the heat exchange element 203
Are formed by connecting the start and end of a heating unit 201 formed by spirally winding a stainless steel plate with a lead wire 202 in the axial direction of the container 101.
For this reason, each heating unit 201 can freely set the width a and the interval b between the spirals. Since the width a can be freely set, dimensions that are convenient for production can be freely selected. In addition, since the interval b between the spirals can be freely set, a uniform heat source having a large heat exchange amount per unit volume can be obtained by reducing the interval b between the spirals. Also, since the beginning and end of the winding are connected,
The heat is uniformly generated from the entire surface of the heat generating unit 201.

Here, the relationship between the amount of heat generated by the heat exchange element 203 and the temperature at which the liquid is heated will be described. The total heat exchange area of the heat exchange element 203 is A, the heat quantity of the electric power supplied from the heating coil 102 is Q, the heat transfer coefficient h is a constant determined by the configuration of the liquid transfer path, and the temperature of the heat exchange element 203 and heat exchange. Assuming that the temperature difference from the temperature of the subsequent fluid is ΔT,
These relationships can be represented by ΔT = Q / (A · h). Therefore, when the amount of heat Q to be given is determined, ΔT can be reduced by reducing the interval b of the spiral structure, increasing the number of spiral turns, and increasing the heat exchange area. That is, local boiling as described in the conventional example can be avoided by reducing the setting of ΔT.

At this time, if the heat exchange element is configured as shown in FIG. 3, the heat exchange efficiency can be further enhanced.
That is, the configuration shown in FIG.
Is a metal plate processed into a wave shape. 302 is a lead wire, and 303 is an insulating sheet inserted between layers.

Since a corrugated metal plate is used as the heat exchange element 301, the contact area with the liquid can be made larger than that of a spiral plate, so that the heat exchange area per unit volume is larger. Is what you can do. Therefore, the heat exchange efficiency can be further increased. Also,
When a metal plate processed into a wave shape is used, the spacing b between the spirals can be appropriately maintained only by inserting the insulating sheet 303, and the heat exchange element 201 using the flat plate described in FIG. In this case, there is no need to devise a method for appropriately maintaining the interval b between the spirals required for the above.

When the heat exchange element is configured as shown in FIG. 4, it is possible to achieve a heat generation distribution in which the temperature of the liquid flowing in the central portion is increased, and as a result, a heating device having a uniform temperature distribution can be realized. Things. That is, the heat exchange element 401 having the configuration shown in FIG. 4 includes a plurality of metal rings 401a to 401c arranged concentrically. The innermost metal ring 401a is made of magnetic stainless steel,
Reference numerals 1b and 401c are made of non-magnetic stainless steel.

With the above configuration, as shown in FIG. 5, the magnetic flux passing through the central portion of the container 101 is maximized. That is, the temperature of the liquid passing through the container 101 is the highest. That is, the eddy current flowing through the heat exchange element 401 due to the high-frequency magnetic field generated by the heating coil 102 is generated in a direction that prevents a change in magnetic flux. Therefore, a portion through which more magnetic flux passes generates a larger eddy current. The magnetic permeability, which indicates the ease with which magnetic flux passes, is approximately 100% for magnetic stainless steel compared to non-magnetic stainless steel.
Doubled. For this reason, as in this embodiment, the magnetic stainless steel ring 4 is provided inside the non-magnetic stainless steel rings 401b and 401c.
When 01a is enclosed, the magnetic flux generated by the heating coil 102 tends to pass through the innermost magnetic stainless steel ring 401a. If the length of the heating coil 102 is not sufficiently long with respect to the diameter of the container 101, the magnetic flux generated by the heating coil 102 will not be parallel to the axial direction of the container 101. That is, schematically, as shown in FIG.
Oval or parabolic. For this reason, the magnetic flux generated by the heating coil 102 is linked to all of the magnetic stainless steel ring 401a, the non-magnetic stainless steel rings 401b, and 401c. For this reason, all of the magnetic stainless steel ring 401a and the non-magnetic stainless steel rings 401b and 401c generate heat, and the calorific value of the magnetic stainless steel ring 401a through which magnetic flux passes most easily becomes the largest. As described above, according to the present embodiment, the container 1
Since the temperature at the center of the fuel cell 01 can be increased, it is particularly effective when the object to be heated has a high viscosity such as petroleum. That is, when it is considered that the passage speed of the liquid is higher in the central portion, the temperature in the central portion can be increased, so that the entire temperature distribution can be made uniform.

In this embodiment, the metal ring is formed in a triple structure. However, it is not particularly necessary to limit the structure to a triple structure.
Also, the material used for the metal ring need not be particularly limited to stainless steel, as long as the magnetic permeability of the metal ring used on the innermost side is larger than the magnetic permeability of the metal ring used on the outer side. , Can achieve the purpose.

In the above embodiments, the object to be heated is a liquid such as water or petroleum. However, the present invention can be applied to a case where the object to be heated is a gas.

[0020]

According to the first aspect of the present invention, there is provided a heat exchange element for exchanging heat with a liquid, a container for accommodating the heat exchange element, and a heating coil wound around the outside of the container for generating a high-frequency magnetic field. A high-frequency power supply means for supplying high-frequency power to a heating coil, wherein the heat exchange element forms a metal plate in a spiral shape and electrically connects a winding start and a winding end with a heating unit in an axial direction of the container. The present invention realizes a heating device having a high heat exchange efficiency, free temperature setting, and a uniform temperature distribution.

According to a second aspect of the present invention, a heating device having a structure in which a corrugated metal plate is used for a heat exchange element, which can increase a contact area with a liquid and particularly enhance heat exchange efficiency is realized. Things.

According to a third aspect of the present invention, the heat exchange element comprises a plurality of metal rings arranged concentrically, and the innermost metal ring is made of a magnetic metal, so that the temperature of the liquid flowing through the central portion is reduced. The object of the present invention is to realize a heating device in which the temperature distribution becomes uniform as a result of the increased heat generation distribution.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a heating device according to an embodiment of the present invention.

FIG. 2A is a perspective view showing a configuration of a heat generating unit of the heat exchange element; FIG. 2B is a cross-sectional view showing a configuration of the heat exchange element;

FIG. 3 is a perspective view illustrating another configuration of the heat exchange element.

FIG. 4 (a) is a plan view showing another configuration of the heat exchange element. FIG. 4 (b) is a plan view showing another configuration of the heat exchange element.

FIG. 5 is an explanatory view illustrating the operation of the heat exchange element shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Container 102 Heating coil 103 High frequency power supply means 104 Fluid transfer means 201 Heat generating unit 203 Heat exchange element 301 Heat exchange element 401 Heat exchange element 401a Metal ring 401b Metal ring 401c Metal ring

 ──────────────────────────────────────────────────の Continuing on the front page (72) Hidekazu Yamashita 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Hideki Omori 1006 Kadoma Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A heat exchange element for exchanging heat with a liquid, a container accommodating the heat exchange element, a heating coil wound around the outside of the container to generate a high-frequency magnetic field, and supplying high-frequency power to the heating coil. A heating device comprising high-frequency power supply means, wherein the heat exchange element is formed by laminating a heat generating unit in which a metal plate is formed in a spiral shape and a winding start and a winding end are electrically connected in the axial direction of the container. 2. The heating device according to claim 1, wherein the heat exchange element uses a metal plate processed into a wave shape. 3. The heating device according to claim 1, wherein the heat exchange element is a plurality of metal rings arranged concentrically, and the innermost metal ring is made of a magnetic metal.