JP5169459B2 - Method for manufacturing heating element and method for manufacturing heating device - Google Patents

Description

  The present invention relates to a method for manufacturing a heating element used in a heating device such as an electric cooker or an electric heater, and a method for manufacturing a heating device using the heating element.

  Generally, a heating element used in an electric cooker, an electric heater, or the like is a linear heating wire, and has a problem that it is easily disconnected due to thermal fatigue or external impact.

Conventionally, in order to solve this problem, the heating element is formed in a band shape having a wave shape, so that the cross-sectional area and the surface area are made wider than the linear shape, and the heating efficiency is improved while suppressing the disconnection. A heating element is known (see, for example, Patent Document 1).
JP-A-5-157240

  However, the belt-like heating element is not sufficiently described with respect to the manufacturing method, and there is a problem that it is unclear how to produce the belt-like heating element.

  An object of the present invention is to provide a method for manufacturing a heating element and a method for manufacturing a heating device in view of the above-described problems, and a method for efficiently manufacturing the belt-shaped heating element.

In order to solve the above problems, the present invention provides a step of forming an insulating layer on the surface of a metal plate serving as a substrate, and a heater material having conductive heat generation characteristics on the insulating layer after the insulating layer is formed. A configuration is adopted in which a powder rolling process for fixing the powder of the above by powder rolling and a heat treatment process for firing the heater material after the powder rolling process are employed.
By adopting such a configuration, in the present invention, the heater material is fixed onto the surface of the metal plate via the insulating layer, so that a belt-like heating element can be manufactured.

Further, the present invention employs a configuration in which the insulating layer is formed from a resin.
By adopting such a configuration, in the present invention, the heater material is fixed through an insulating layer formed of resin.

Moreover, this invention employ | adopts the structure that after forming the said insulating layer, the resin layer which assists adhering of the said heater material is formed in the surface of the said insulating layer.
By adopting such a configuration, in the present invention, the heater material can be easily fixed on the insulating layer by powder rolling.

Further, the present invention employs a configuration in which the insulating layer is made of ceramic.
By adopting such a configuration, in the present invention, since the insulating layer is made of ceramic and has heat resistance, it is possible to suppress melting of the insulating layer even if the heating element generates heat at a high temperature. The heat generation allowable range of the heating element can be expanded.

Further, the present invention employs a configuration in which the metal plate is molded after the powder rolling step and before the heat treatment step.
By adopting such a configuration, in the present invention, the shape of the heating element can be formed into a desired shape by forming the metal plate before firing in the heat treatment step.

Moreover, this invention employ | adopts the manufacturing method of the heating apparatus which has the manufacturing method of the said description.
By adopting such a configuration, in the present invention, a heating device having a belt-like heating element can be obtained.

In the present invention, a step of forming an insulating layer on the surface of a metal plate serving as a base material, and a powder for fixing a powder of a heater material having conductive heat generation characteristics on the insulating layer by powder rolling after the formation of the insulating layer By adopting a configuration including a rolling process and a heat treatment process for firing the heater material after the powder rolling process, the heater material is fixed on the surface of the metal plate via an insulating layer, thereby forming a belt-like shape. The heating element can be manufactured.
Therefore, in the present invention, a wide belt-like heating element can be easily manufactured by fixing the powder of the heater material on the metal plate, and the base material is formed into a desired shape by being formed from the metal plate. A heating element that can be processed can be manufactured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same reference numerals are assigned to the same members. In order to facilitate understanding, the scales of these drawings are appropriately changed.

First, the configuration of the heating element manufactured in the present embodiment will be described.
FIG. 1 is a perspective view showing a heating element 1 in the present embodiment.
The heating element 1 includes a metal plate 21 serving as a base material, insulating layers 22 formed on both surfaces of the metal plate 21, and heat generating layers 23 stacked on each insulating layer 22.

The metal plate 21 serves as a skeleton of the shape of the heating element 1, and for example, a stainless plate or the like is used.
The heat generation layer 23 is formed of a heater material having conductive heat generation characteristics and is configured to generate heat when energized.
The insulating layer 22 is formed between the metal plate 21 and the heat generating layer 23 in order to prevent a current flowing through the heat generating layer 23 from leaking to the metal plate 21.
Hereinafter, a method for manufacturing the heating element 1 having the above configuration will be described.

(First embodiment)
First, a method for manufacturing the heating element 1 in which the insulating layer 22 is formed from a resin will be described with reference to FIGS.
FIG. 2 is a flowchart showing a manufacturing process of the heating element 1 in the first embodiment.
FIG. 3 shows a configuration diagram of a powder rolling apparatus D for fixing the material powder 2 of the heater material having conductive heat generation characteristics to the metal plate 21 by powder rolling.
Here, the structure of the powder rolling apparatus D shown in FIG. 3 will be described first.

  The powder rolling apparatus D conveys the material powder 2 stored in the hopper 3A and the hopper 3B for storing the material powder 2 of the heater material having conductive heat generation characteristics and the rolling roller 4A to be described later to the peripheral surface of the rolling roller 4A. The belt feeder 5B, the belt feeder 5B that conveys and feeds the material powder 2 stored in the hopper 3B toward the circumferential surface of the rolling roller 4B described later, the circumferential surface of the rolling roller 4A, and the rolling roller 4B. It has the structure which has rolling roller 4A, 4B which rolls the metal plate 21 in which the material powder 2 and the insulating layer 22 which were supplied to the surrounding surface were formed.

  As the material powder 2, for example, a heater material powder made of an aluminum (Al) alloy is used.

  The hopper 3A is configured to store the material powder 2 and to have a hollow structure that gradually decreases in diameter as the cross-sectional shape goes downward. The hopper 3B has the same configuration as the hopper 3A, and is provided symmetrically with a predetermined distance from the hopper 3A.

The belt feeder 5A is provided below the hopper 3A, and is configured to convey the material powder 2 supplied from the lower part of the hopper 3A by being connected to a rotation driving mechanism (not shown) and rotating. Further, the belt feeder 5A has a conveyance destination positioned above the rolling roller 4A and supplies the material powder 2 onto the peripheral surface of the rolling roller 4A. The belt feeder 5A has substantially the same width as that of the rolling roller 4A, and is configured to be able to supply the material powder 2 uniformly over the width direction of the rolling roller 4A.
The belt feeder 5B has the same configuration as the belt feeder 5A, is provided below the hopper 3B, and is configured to supply the material powder 2 onto the peripheral surface of the rolling roller 4B.

  The rolling rollers 4A and 4B are a pair and are provided below the belt feeder 5A and the belt feeder 5B. Moreover, rolling roller 4A, 4B is arrange | positioned so that a mutual surrounding surface may mutually oppose at a predetermined space | interval. And rolling roller 4A, 4B is the structure which rolls the member inserted between rolling roller 4A, 4B by rotationally driving with a rotation drive mechanism not shown.

  Next, the manufacturing process of the heating element 1 will be described with reference to FIG.

First, a resin is applied to the surface of the metal plate 21 to form the insulating layer 22 (step S1).
The insulating layer 22 is made of resin, and is formed, for example, by applying polyphenylene sulfide (hereinafter referred to as PPS) on the surface of the metal plate 21 with a uniform thickness and then drying (see FIG. 3). ).
The insulating layer 22 may be formed on the surface of the metal plate 21 by the powder rolling apparatus D by powder rolling of PPS.

Next, using the powder rolling device D, the material powder 2 is fixed on the insulating layer 22 formed on the metal plate 21 by powder rolling (powder rolling process: step S2).
As shown in FIG. 3, the powder rolling apparatus D carries out the material powder 2 stored in the hopper 3A from the lower part of the hopper 3A by driving the belt feeder 5A, and conveys it toward the rolling roller 4A. And belt feeder 5A supplies material powder 2 to the peripheral surface of rolling roller 4A continuously over the width direction of rolling roller 4A. At the same time, the powder rolling apparatus D conveys the material powder 2 stored in the hopper 3B toward the rolling roller 4B by the drive of the belt feeder 5B, and supplies it to the peripheral surface of the rolling roller 4B.

  The rolling rollers 4A and 4B are inserted between the material powder 2 supplied between the rolling rollers 4A and 4B and the rolling rollers 4A and 4B from the upper side to the lower side and conveyed by being rotationally driven at a predetermined distance. The metal plate 21 on which the insulating layer 22 is formed is rolled. By the rolling, the material powder 2 becomes a powder layer and is fixed onto the insulating layer 22 formed on the metal plate 21.

Then, the metal plate 21, the insulating layer 22, and the material powder 2 integrated by the powder rolling process are molded into a desired shape (step S3).
The integrated metal plate 21, insulating layer 22, and material powder 2 are molded using a corrugated press mold or the like to produce a corrugated heating element 1 as shown in FIG. Will be.

Finally, the metal plate 21, the insulating layer 22, and the material powder 2 molded into a desired shape are placed in a heating furnace and heated to fire the material powder 2 (heat treatment step: step S4).
The material powder 2 is heated and sintered at a temperature equal to or lower than the melting point of the material powder 2, whereby the material powder 2 is firmly fixed on the insulating layer 22 and becomes the heat generating layer 23 (see FIGS. 1 and 6). ).
Here, if the insulating layer 22 made of resin has thermosetting property, it is thermally cured and firmly fixed on the metal plate 21.

  Through the heat treatment step, a belt-like heating element 1 having a desired shape is manufactured.

Therefore, according to 1st Embodiment of this invention mentioned above, the process of forming the insulating layer 22 in the surface of the metal plate 21 used as a base material, and after forming the insulating layer 22, it is the conductive heat generation characteristic on the insulating layer 22. The heater material has an insulating layer by adopting a configuration comprising a powder rolling step for fixing the material powder 2 of the heater material having powder by powder rolling and a heat treatment step for firing the heater material after the powder rolling step. By fixing on the surface of the metal plate 21 via 22, the belt-like heating element 1 can be manufactured.
That is, in the first embodiment, the wide belt-like heating element 1 can be easily manufactured by fixing the material powder 2 of the heater material on the metal plate 21, and the base material is formed from the metal plate 21. Thus, the heating element 1 that can be molded into a desired shape can be manufactured.

  In the first embodiment, the insulating layer 22 is formed of a resin so that the heater material is fixed via the insulating layer 22 formed of the resin, and the metal plate 21 is heated during heat generation. It is possible to prevent the current flowing through the heat generating layer 23 from leaking.

  Moreover, in 1st Embodiment, it is after the said powder rolling process, Comprising: By adopting the structure which shape | molds the metal plate 21 before the said heat treatment process, before baking of the said heat treatment process, it is a metal plate. By molding 21, the shape of the heating element 1 can be molded into a desired shape.

(Second Embodiment)
Then, the manufacturing method of the heat generating body 1 in which the insulating layer 22 is formed from a ceramic is demonstrated with reference to FIG.4 and FIG.5.
FIG. 4 is a flowchart showing a manufacturing process of the heating element 1 in the second embodiment.
FIG. 5 is a diagram illustrating a manufacturing process of the heating element 1 in the second embodiment.
In the following description, descriptions of parts having the same configurations as those of the first embodiment are omitted.

In the first embodiment, since the insulating layer 22 is made of resin, if the heating element 1 generates heat to a temperature of about 250 degrees or more, for example, depending on the type of resin used for the insulating layer 22 Therefore, the allowable range of heat generation of the heating element 1 is preferably approximately 250 degrees or less. Therefore, in the second embodiment, a ceramic having heat resistance is employed for the insulating layer 22 in order to expand the allowable heat generation range of the heating element 1 compared to the first embodiment.
In the second embodiment, the material powder 2 is, for example, a heater material that is an alloy made of nickel (Ni) of 10 to 30 wt%, chromium (Cr) of 30 wt%, and the balance of iron (Fe) and inevitable impurities. The powder is used.

  Hereinafter, with reference to FIG.4 and FIG.5, it demonstrates according to the manufacturing process of the heat generating body 1 in 2nd Embodiment.

First, the insulating layer 22 made of ceramic is formed on the surface of the metal plate 21 (step S5).
The insulating layer 22 is made of an unfired ceramic, and is formed by, for example, dissolving silica or alumina in a solvent and applying the uniform thickness on the surface of the metal plate 21 and then drying (see FIG. 5 (a)).
In addition, it is preferable to select a ceramic that can be fired at a temperature in the vicinity of the firing temperature of the material powder 2.

Next, a resin is applied on the insulating layer 22 formed on the metal plate 21 (step S1).
The purpose of applying the resin is that the insulating layer 22 is made of ceramic and therefore has low ductility, and it is difficult for the material powder 2 to adhere to the insulating layer 22 by direct powder rolling, so that the resin is more ductile than ceramic. This is because the material powder 2 can be easily fixed to the insulating layer 22 by providing the insulating layer 22 with the layer formed from the above. After applying the resin, the resin layer 24 is formed on the insulating layer 22 by drying (see FIG. 5B).

And using the powder rolling apparatus D (refer FIG. 3), the material powder 2 is fixed by the powder rolling via the resin layer 24 on the insulating layer 22 formed in the metal plate 21 (powder rolling process: step S2). .
By the powder rolling process, the material powder 2 is fixed onto the insulating layer 22 via the resin layer 24 as shown in FIG.

  Then, the metal plate 21, the insulating layer 22, the resin layer 24, and the material powder 2 integrated by the powder rolling process are molded into a desired shape (step S3).

Next, the molded metal plate 21, insulating layer 22, resin layer 24, and material powder 2 are placed in a heating furnace to perform a resin removal process (step S6).
Here, the resin layer 24 that has finished the role of assisting the fixing of the material powder 2 onto the insulating layer 22 is heated at about 400 degrees to volatilize the resin and perform the resin removal treatment. By performing the de-resining process, the quality of the finished product can be improved.

Finally, the metal plate 21, the insulating layer 22 and the material powder 2 that have undergone the resin removal treatment are placed in a heating furnace and heated, and the material powder 2 and the insulating layer 22 made of unfired ceramic are fired (heat treatment step) : Step S4).
The material powder 2 is heated and sintered at a temperature equal to or lower than the melting point of the material powder 2, and the material powder 2 is firmly fixed on the insulating layer 22 to form the heat generation layer 23. The shape of the insulating layer 22 is fixed by being baked and cured.

  Through the heat treatment step, the material powder 2 is sintered to form the heat generating layer 23, and the insulating layer 22 made of ceramic is sintered to manufacture the heat generating element 1 having a desired shape (see FIG. 6).

  Therefore, according to the second embodiment described above, after the insulating layer 22 is formed, the configuration in which the resin layer 24 that assists the fixing of the material powder 2 of the heater material is formed on the surface of the insulating layer 22 is adopted. Thus, the material powder 2 can be easily fixed on the insulating layer 22 by powder rolling.

  In the second embodiment, since the insulating layer 22 is formed of ceramic, the insulating layer 22 is formed of ceramic and has heat resistance, so that the heating element generates heat at a high temperature. Even so, melting of the insulating layer 22 and the like can be suppressed, and the heat generation allowable range of the heating element 1 can be expanded.

(Third embodiment)
In 3rd Embodiment, the manufacturing method of the heating apparatus 50 using the heat generating body 1 manufactured in the said 1st and 2nd embodiment is demonstrated with reference to FIG.6 and FIG.7.
FIG. 6 shows a side view of the heating unit 30 using the heating element 1.
FIG. 7 is a plan view of a heating device 50 provided with a plurality of heating units 30.

  The heating unit 30 includes a heating element 1 molded into a wave shape, and a pair of support plates 30A and 30B that sandwich the heating element 1 in the thickness direction.

The support plate 30 </ b> A includes a metal plate 21 </ b> A and an insulating layer 22 </ b> A, and is fixed so that the insulating layer 22 </ b> A faces the heat generating layer 23 of the heat generating element 1. With such a configuration, it is possible to prevent the current flowing through the heat generating layer 23 from leaking to the side where the metal plate 21A is provided.
The support plate 30B is provided on the opposite side to the side on which the support plate 30A is provided, and is composed of a metal plate 21B and an insulating layer 22B, similar to the support plate 30A. On the other hand, the insulating layer 22B is fixed so as to oppose.
When the wave-shaped heating element 1 is sandwiched from the thickness direction by the support plate 30A and the support plate 30B, a plurality of hollow spaces 40A are formed between the support plate 30A and the heating element 1, and the support plate 30B. A plurality of hollow spaces 40B are formed between the heating element 1 and the heating element 1.

Next, the configuration of the heating device 50 using the heating unit 30 will be described with reference to FIG.
The heating device 50 is configured to include a plurality of heating units 30, and an electrode 51 </ b> A (anode) and an electrode 51 </ b> B (cathode) that cause a current to flow through the heating unit 30 to generate heat.
The heating unit 30 has a circular arc shape with a predetermined curvature and is concentrically arranged at predetermined intervals in the radial direction. One end of the heat generating layer 23 of the heating element 1 is joined to the electrode 51A, and the other end is the electrode 51B. Joined with.
Note that a brazing material may be used for the joining.

In the heating device 50 having such a configuration, when the heating element 1 is energized by the electrodes 51A and 51B, the heating layer 23 generates heat. For example, the hollow space 40A and the hollow space 40B ( It can be made hot air by applying heat in the process of passing through FIG.
Therefore, in 3rd Embodiment, since the heating apparatus 50 forms the heat generating body 1 in the strip | belt shape which has a wave shape, since a cross-sectional area becomes large rather than linear shape and a disconnection can be suppressed, a product life is extended, Since the surface area in contact with air is increased, the heating efficiency can be improved.

  As mentioned above, although preferred embodiment of this invention was described referring drawings, this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the third embodiment described above, it has been described that the heating plate 30 uses the support plates 30A and 30B that sandwich the heating element 1. However, instead of the support plates 30A and 30B, a configuration in which two linear heating elements 1 are used and held may be used. Furthermore, the heating unit 30 may be formed in a honeycomb structure by combining the heating elements 1.

It is a perspective view which shows the heat generating body in embodiment of this invention. It is a flowchart which shows the manufacturing process of the heat generating body in 1st Embodiment of this invention. It is a lineblock diagram of a powder rolling device in an embodiment of the invention. It is a flowchart which shows the manufacturing process of the heat generating body in 2nd Embodiment of this invention. It is a figure explaining the manufacturing process of the heat generating body in 2nd Embodiment of this invention. It is a side view of the heating part in 3rd Embodiment of this invention. It is a top view of the heating apparatus in 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Heat generating body, 2 ... Material powder (powder), 21 ... Metal plate, 22 ... Insulating layer, 24 ... Resin layer, 50 ... Heating apparatus

Claims (5)

Forming an insulating layer on the surface of the metal plate to be a base;
After forming the insulating layer, a powder rolling step of fixing the powder of the heater material having conductive heat generation characteristics on the insulating layer by powder rolling;
After the powder rolling step, the step of molding the metal plate,
And a heat treatment step of firing the heater material after the molding process .   The method for manufacturing a heating element according to claim 1, wherein the insulating layer is formed of a resin.   2. The method of manufacturing a heating element according to claim 1, wherein after the insulating layer is formed, a resin layer that assists the fixing of the heater material is formed on a surface of the insulating layer.   The method of manufacturing a heating element according to claim 3, wherein the insulating layer is made of ceramic. The manufacturing method of the heating apparatus which has a manufacturing method of Claims 1-4 .

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