KR100338239B1 - Electric heating unit and its manufacturing method - Google Patents

Abstract

In the groove 2 provided on the surface of the heat insulating main body 1 composed mainly of the heat insulating material, a heat generating element 3 processed into a waveform having an amplitude larger than the width of the groove 2 is provided, and both curved portions in the width direction of the heat generating element 3 are provided. 3a is integrally supported by the heat insulating main body 1 by entering into the heat insulating main body 1 from both side walls 2b of the groove 2. The heat insulating main body 1 is provided with a refractory groove bottom forming member 10 made separately from the heat insulating main body 1 to cover the bottom portion 2a of the groove 2 so that the surface of the groove opening side is exposed from the heat insulating main body 1. It is integrally supported by. The heat generating element 3 is disposed from the groove bottom forming member 10 toward the groove opening side, and is integrally supported by the heat insulating main body 1 so as to be in contact with a portion of the surface of the groove bottom forming member 10, and within the groove 2. It is exposed to the outside of the heat insulation body 1.

Description

Electric heating unit and its manufacturing method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric heating unit used in a heating device such as a furnace and a method of manufacturing the same. More specifically, the heating element processed into a wave is integrally formed in a groove provided on the surface of a heat insulating main material mainly comprising a heat insulating material such as a ceramic fiber. It relates to a heating unit which is supported by a mold and a method of manufacturing such a unit by vacuum molding.

An electric heating unit formed by integrally embedding a planar resistive heating element processed into a wave shape integrally with a bottom portion of a groove provided on a surface of a heat insulating main composed mainly of a ceramic fiber and a manufacturing method by vacuum forming thereof are disclosed in US Patent Nos. 4,575. , Japanese Patent Application Laid-Open No. 60-243992. In this structure, the corrugated heating element can support itself near the surface of the insulating main body, and the radiation of heat to the outside becomes easier than the conventional coiled heating element in which the heating element is distributed with a constant width in the thickness direction of the insulating main body, Therefore, there is an advantage that the overheating of the heating element can be made smaller than before.

However, the above heating unit has a problem as mentioned below. 18 and 19 show part of the heating unit, reference numeral 1 denotes a heat insulating main material mainly composed of ceramic fibers, reference numeral 1a denotes a heating surface thereof, and reference numeral 1b denotes a heating surface. The non-heating cold surface opposite to (1a), reference numeral 2 denotes a groove formed in the heating surface 1a, reference numeral 2a denotes the bottom of the groove 2, and reference numeral 2b denotes the groove 2 In both side walls of the heat generator, reference numeral 3 denotes a heating element processed into a waveform, and reference numeral 3a denotes curved portions on both sides in the width direction of the heating element 3. As shown in these figures, only a small part of the heating element 3 is exposed to the free space in the bottom portion 2a of the groove 2, and most are surrounded by the heat insulating body 1, Moreover, the curved part 3a of the heat generating body 3 penetrates the both side walls 2b of the groove | channel 2, and is fully embedded inside the heat insulation main body 1. In this structure, the placenta of the surface of the heat generating element 3 is covered with the heat insulating main body 1, and among all the surfaces of the heat generating element 3, the ratio of the exposed surface which can freely radiate thermal energy toward the space is remarkable. low. Therefore, not only is the heat generating body 3 easy to overheat, but the amount of heat which runs through the heat insulating layer of the heat insulating main body 1 to the unheated cold surface 1b side becomes large. Therefore, when heating efficiency is not enough, especially when it is used at high temperature, there exists a problem that deterioration, consumption of the heat generating body 3, and disconnection by it occur, and sufficient lifetime is not obtained.

From this problem, as shown in FIG. 20, at the position away from the bottom portion 2a of the groove 2 toward the opening side, the curved portions 3a of the heating element 3 have both side walls 2b of the groove 2. The heating unit which came in into the heat insulation body 1 from the inside of the heat insulation body 1, was embedded in the heat insulation body 1, and the whole surface of the heat generating body 3 in the groove | channel 2 was exposed to the outside of the heat insulation body 1 was proposed. For example, in Japanese Unexamined Patent Application, First Publication No. 2-89300, the number of the heating elements is not one but two, and one example of such a heating unit is disclosed. 21 shows an example of a manufacturing process of such a heating unit, in which reference numeral 4 is a vacuum forming mold, and 5 is a screen made of a porous metal plate or the like arranged horizontally in the mold 4, drawing. Reference numeral 6 is a vacuum suction port provided in the wall portion of the mold 4 which is lower than the screen 5. When manufacturing a heating unit, the 1st mask member 7 which is an angular bar shape for forming an opening side part in the heat generating body 3 of the groove | channel 2 is first mounted on the screen 5, Waveform heating element 3 is placed thereon, and a second mask member 8, which is a rectangular bar for forming a bottom side portion of the heating element 3 of groove 2, is placed thereon. Then, the well-known vacuum molding is performed, and the heat insulating material layer 9 serving as the heat insulating body 1 is formed around the heating element 3 and the mask members 7 and 8 above the screen 5, followed by heat drying curing. After that, the mask members 7 and 8 are removed from the heat insulating main body 1 to form the grooves 2. Since the first mask member 7 can be removed to the opening side of the groove 2, the removal operation is easy. On the other hand, since the heat generating body 3 exists in the opening side of the groove | channel 2 with respect to the 2nd mask member 8, the space | interval between the bottom of the groove | channel 2 and the heat generating body 3 with the 2nd mask member 8 is present. It is necessary to move in the longitudinal direction of the groove 2 and pick it up from one end of the groove 2. Therefore, the removal operation of the 2nd mask member 8 is performed by hand one by one, and there exists a problem that this process is very complicated.

An object of the present invention is to provide a heating unit that can expose as much of the surface of the heating element as possible to the outside of the heat insulating main body, and is easy to manufacture.

Another object of the present invention is to provide a method for easily and inexpensively manufacturing a heating unit in which as much of the surface of the heating element as possible is exposed to the outside of the heat insulating body.

In the heating unit according to the present invention, a heating element processed into a waveform having an amplitude larger than the width of the groove is installed in a groove provided on the surface of the thermal insulation main material mainly comprising a heat insulating material, and the curved portions on both sides of the heating direction in the width direction of the heating element are both sidewalls of the groove. In the electric heating unit integrally supported by the heat insulating main body by entering into the heat insulating main body, a refractory groove bottom forming member made separately from the heat insulating main body covers the bottom of the groove so that the surface of the groove opening side is exposed from the heat insulating main body. Integrally supported by the heat insulating main body, the heating element being disposed from the groove bottom forming member toward the groove opening side, integrally supported by the heat insulating main body to be in contact with a part of the surface of the groove bottom forming member, and in the groove outside the heat insulating main body. It is characterized by being exposed to.

The heating unit according to the present invention is an electric heating unit which is manufactured by vacuum forming and in which a heating element processed in a wave shape is integrally supported in a groove of a surface of a heat insulating molded article having a ceramic fiber as a main component. In the dimensional relationship of the cross section orthogonal to the steel-working section of the heating element processed into a wave form at least partly in contact with the steel-working section along the groove-forming steel-working section set or placed in a predetermined position, it is almost equivalent to the width of the steel-building part among the amplitudes of the heating-element waveforms. By contacting the refractory groove bottom forming member having an outer dimension covering the portion of the heating element with a part of the heating element, and by placing the vacuum not by contacting with the steel part, the groove bottom forming member and the heating element are formed in the insulating molded body. It is characterized by being integrally supported.

The manufacturing method of the heating unit by this invention is a method of manufacturing the electrical heating unit by which vacuum heating was integrally supported by the heat generating body processed by the wave in the groove of the surface of the heat insulation molded object which has a ceramic fiber as a main component, and vacuum forming In the dimensional relationship of the cross-section orthogonal to the steel-working section having a heating element processed into a waveform so that at least a part thereof contacts the steel-working section along the groove-forming steel-working section provided at a predetermined position of the mold, the width of the steel-working section has The insulating molded body is placed in the groove bottom forming member and the heating element by placing a refractory groove bottom forming member having an outer dimension covering almost a portion of the heating element in contact with a portion of the heating element and vacuum forming the contact bottom portion so as not to contact the steel part. It is characterized in that the molded integrally with.

The manufacturing method of the heating unit by this invention is demonstrated further concretely, as follows.

A groove member for forming a groove is formed by placing a mask member on the screen in the vacuum forming die. Next, the corrugated heating element is placed on the mask member, and the groove bottom forming body is placed on the heating element. In this state, the slurry containing the ceramic fiber is introduced into the space above the screen in the mold, and vacuum molding is performed. As a result, a ceramic fiber in the slurry is deposited on each surface of the upper surface of the screen in the mold, the mask member, the heating element, and the groove bottom forming member, thereby forming a heat insulating body that serves as a heat insulating main body. The ceramic fiber is not deposited on the portion where the mask member is located. In addition, the groove bottom forming member also acts as a mask, and ceramic fibers are not deposited around the heating element portion disposed in close proximity to the groove bottom forming member. When the vacuum molding is finished, the molded product is taken out of the mold, dried by heat drying, and the mask member is removed. As a result, the groove bottom forming member is integrally supported at the bottom of the groove of the heating surface of the heat insulating main body, and the heating of the present invention is integrally supported by the heat insulating main body so that the heating element is exposed to the outside of the heat insulating main body in the groove. The unit is obtained.

In the method of the present invention, the heating unit supported so that the heating element is exposed in the groove of the surface of the heat insulating main because the groove bottom forming member acts as a mask to prevent the heat insulating material from being deposited to surround the surface of the heat generating element. Is obtained. In addition, the groove forming steel parts such as the mask member can be easily removed to the opening side of the groove, and since the groove bottom forming member is made of a refractory material, it is not necessary to remove it from the molded product, but is used as a part of the heat insulating main body of the heating unit. It can provide, and the removal effect of a complicated mask member by manual labor as before becomes unnecessary. Therefore, according to the method of the present invention, the heating unit supported so that the heating element is exposed in the surface groove of the heat insulating main body can be manufactured easily and inexpensively.

According to the heating unit of the present invention, most of the surface of the heat generating element can be isolated from the heat insulating main body by the groove bottom forming member to be exposed to the outside of the heat insulating main body, so that the heat can be radiated freely from the heat generating element toward the space, The overheating of is small and heating efficiency becomes extremely high.

When manufacturing the heating unit using the screen, the shape of the screen is appropriately selected from flat, cylindrical, cylindrical dividing surfaces, and other curved surfaces depending on the shape required for the heating unit.

It is preferable to form by forming the grooved portion for forming the groove by placing a mask member made of a metal rod such as aluminum on the screen. However, you may form the grooved steel plate part by putting the mask member which formed the same porous metal plate as the screen in square shape on the screen. Moreover, you may use the screen which integrally formed the groove formation iron part in the upper surface.

The width of the groove forming groove is equal to the width of the groove of the heat insulating main body, and is smaller than the waveform amplitude of the heating element. The outer width of the groove bottom forming member is preferably about the width of the groove, and more preferably about the width of the groove bottom forming member. If too small, a sufficient mask effect cannot be expected. On the contrary, if too large, deposition of sufficient heat insulating material for supporting the heating element may not be obtained.

Although the material of the heat insulating material which comprises a heat insulating main body is arbitrary, ceramic fiber is especially preferable. In addition, the material of the groove bottom forming member can be appropriately selected, and is not particularly limited. However, a lightweight refractory material is preferable, and in the case where the heat insulating material is a ceramic fiber, a molded product containing the ceramic fiber as a main component at the matching point of the material as the whole heating unit This is especially suitable.

The molding density of the groove bottom forming member can be adjusted in a wide range according to the shape, the desired strength, the heat insulating performance, and the like by the prior art. For example, as the groove bottom forming member, a low density molded article having a plurality of cavities or bubbles therein can be used.

The surface facing the heating element exposed from the heat insulating main body of the groove bottom forming member may be a high radiator or a high reflector of heat. A paste-like or liquid commercial item containing a powder of silicon carbide or the like is available as a heat-spinning material, and a groove bottom forming member whose surface is covered with a high-spinning material is easily dried by coating or impregnating it on a desired surface. It is possible to manufacture. Of course, if such a high-radioactive fiber can be obtained in the future, it can also be used as a groove bottom forming member by directly molding it by a known technique.

Formation of the groove bottom forming member can be carried out in many variations, and it is possible to select an optimal one depending on the use mode, purpose, and the like of the heating unit.

For example, the surface of the groove opening side of the groove bottom forming member is formed with unevenness, and the heating element is in contact with a part of the iron portion of the uneven surface. In this way, the heating element can be reliably supported at the convex portion of the uneven surface, and furthermore, since the heating element does not contact the concave portion of the uneven surface of the groove forming member, the exposed area of the heating element can be increased again.

For example, a set of grooves extending in the longitudinal direction of the grooves is formed in a portion except the width direction both sides of the surface on the groove opening side of the groove bottom forming member, so that the surface is formed into an uneven shape. In this case, the heating element can be reliably supported in the concave portions on both sides of the concave shape, and since the heating element does not contact the groove forming member in the wide concave portion, the exposed area of the heating element is increased again. The heating element is usually formed in a planar shape, but when such a groove forming member is used, a portion of the heating element exposed in the groove may be formed in an iron shape such as to protrude into the recess of the groove bottom forming member.

For example, a set of barbed wires extending in the longitudinal direction of the groove is formed in the width direction center portion of the surface on the groove opening side of the groove bottom forming member, so that this surface is formed with irregularities.

For example, a plurality of projections are formed on the surface on the groove opening side of the groove bottom forming member, so that this surface is formed into an uneven shape. The planar shape and cross-sectional shape of the projection are arbitrary.

Moreover, this surface can also be formed uneven | corrugated by providing a some factor place in the surface of the groove opening side of a groove bottom formation member. For example, a plurality of elements can be formed on one side of the groove forming member by making a honeycomb shape.

For example, a heating element supporting portion which is integrally supported on both sidewalls of the groove and opposite to each other in the width direction of the groove is provided on both sides in the width direction of the groove bottom forming member, and the curved portion of the heating element is provided on this recess. Is connected and supported.

For example, the projection for gripping the width direction center part of a heat generating body is formed in the width direction center part of the bottom of a urine bath. In this way, the part of the heat generating body exposed in the groove can be reliably maintained.

In some cases, a plurality of heat generating elements are supported in one groove of the heat insulating main body. For example, in this case, at least one heating element spaced by a refractory spacer integrally supported on both sidewall portions of the groove is provided from the heating element in contact with the groove bottom forming member to the groove opening side, and the plurality of heating elements are provided. Is supported at intervals in the depth direction of the flaw. The spacers between the heat generating elements also serve as masks during vacuum forming in the same manner as the groove forming members, and can be used as they are part of the heat insulating main body of the heating unit without having to be removed from the moldings.

Example

Hereinafter, some embodiments of the present invention will be described with reference to the drawings. In these embodiments, the parts corresponding to the above-described conventional examples are given the same reference numerals, and the parts corresponding to each other are given the same reference numerals.

First embodiment

1 and 2 show the main parts of the heating unit of the first embodiment.

In FIG. 1 and FIG. 2, in the bottom part 2a of the groove | channel 2 of the cross-sectional weak rectangle formed in the heating surface 1a of the heat insulating main body 1 whose main component is a ceramic fiber as a heat insulating material. The plate-shaped refractory groove bottom forming member 10 made separately from the heat insulating main body 1 covers the bottom 2a so that the surface of the groove 2 opening side is integrally supported so as to be exposed from the heat insulating main body 1. have. The corrugated heating element 3 is disposed from the groove bottom forming member 10 to the groove 2 opening side, and the curved portions 3a on both sides of the heat insulating body 1 are formed on both side walls 2b of the groove 2. It enters in and is integrally supported by the heat insulating main body 1.

The groove bottom forming member 10 is preferably made of a molded article mainly composed of the same ceramic fiber as the heat insulating main body 1, and the length of the grooves 2 on both sides in the width direction of the surface on the opening side of the grooves 2. The cross-sectional cross-sectional steel bar 11 extending in the direction is integrally formed, and a wide set of the recesses 12 having a cross-sectional room shape extending in the longitudinal direction of the groove 1 are formed therebetween. Thereby, the surface of the groove | channel 2 opening side of the groove bottom formation member 10 is formed in uneven | corrugated shape. The outer width of the groove bottom forming member 10 is slightly larger than the width of the groove 2, and the inner width of the recess 12 is slightly smaller than the width of the groove 2. Both side walls 2b of the groove 2 are located in the widthwise middle portion of the front face of the steel bar 11 on both sides of the groove bottom forming member 10, and the portions in the width direction outside of the steel bar 11 on both sides are The groove bottom forming member 10 is reliably supported by the heat insulating body 1 by being embedded in the portion extending to the bottom portion 2a of both side walls 2b. And the part of the side of the recess 12 of the front of the barbed 11 of both sides, and the surface of the recess 12 are exposed in the groove | channel 2.

The heating element 3 is arranged to contact the front of the iron-like portions, i.e., the iron bars 11, on both sides of the groove bottom forming member 10 in portions that are extended to both sides of the grooves 2 through the side walls 2b. have. And in the wide part corresponding to the recess 12 of the groove bottom forming member 10, the heat generating body 3 completely falls away from the heat insulating body 1 and the groove bottom forming member 10, The surface is exposed in the groove 1. Therefore, heat can be radiated freely from the heat generating element 3 to the space, and the heat generating element 3 becomes hard to overheat, and the amount of heat running off toward the unheated cold surface 1b is reduced. Therefore, heating efficiency improves and the lifetime of the heat generating body 3 becomes long.

3 shows an example of the manufacturing process of the heating unit.

The manufacturing apparatus shown in FIG. 3 is the same as that shown in FIG. 21 mentioned above. For example, the mold 4 is formed in a box shape with a suitable material such as acrylic resin. The screen 5 is arranged horizontally in the middle of the height in the mold 4. The vacuum suction port 6 is connected by the well-known vacuum suction means which is not shown in figure.

For example, manufacture of a heating unit is performed as follows.

First, on the screen 5, an aluminum rectangular mask member 7 is placed. As a result, the groove-forming barbed portion is formed on the screen 5. Next, the heating element 3 is placed on the mask member 7, and the groove bottom forming member 10 is placed on the heating element 3. At this time, the curved portions 3a on both sides of the heating element 3 protrude outward from the mask member 7 and the groove bottom forming member 10 in the width direction. In this state, the mold 4 is settled in the slurry containing water, the binder, and the ceramic fiber, and the vacuum suction means is operated to apply a vacuum suction force to the space below the screen 5, and the screen 10 The slurry is introduced into the space above. The vacuum suction force acts on the slurry through the screen 5, and when the slurry flows into the upper surface of the screen 5 by the suction force, the ceramic fibers dispersed in the slurry are separated from the screen 5 in the mold 4. The heat insulating material layer 9 which becomes the heat insulating main body 1 is formed by depositing on the upper surface, the mask member 7, the heat generating body 3, and the surface of the groove bottom forming member 10, respectively. The ceramic fiber is not deposited on the portion where the mask member 7 is present. In addition, the ceramic fire is deposited around the curved portion 3a of the heating element 3 protruding outward from the mask member 7 and the groove bottom forming member 10 in the width direction, and the curved portion 3a is the heat insulating main body 1. ), But the groove bottom forming member 10 also acts as a mask for inhibiting vacuum suction force, and the groove bottom forming member 3 and the groove bottom forming member 3 and the mask member ( Since the portion of the heating element 3 between 7) becomes the shade of the groove bottom forming member 3 with respect to the flow of the slurry, the ceramic fiber is formed around the heating element 3 in and around the urine 12. Is not deposited. When the vacuum molding is completed, the molded product is taken out of the mold 4, dried by heat drying, and the mask member 7 is removed. As a result, the groove bottom forming member 10 is integrally supported by the bottom portion 2a of the groove 2 of the heating surface 1a of the heat insulating body 1, and the heating element 3 is formed by the groove 2. The heating unit shown in FIG. 1 and FIG. 2 integrally supported by the heat insulation main body 1 so that the heat insulation body 1 may be exposed out of the heat insulation body 1 is obtained. In this heating unit, the surface corresponding to the screen 5 of the mold 4 becomes the heating surface 1a, and the part in which the mask member 7 was provided of the groove 2 formed in this heating surface 1a is provided. It becomes an opening side part in the heat generating body 3.

The vacuum forming is well known, and in the state where the mask member 7, the heating element 3 and the groove bottom forming member 10 are supported at a predetermined position in the mold 4 with a suitable jig, respectively, After forming a caustic mold that can be supported and peeling off the jig, the main molding is performed.

The cross-sectional shape of the groove 11 and the recess 12 of the groove bottom shaping | molding member 10 is not limited to a square shape, It can change suitably.

Second embodiment

4 and 5 show main parts of the heating unit of the second embodiment.

In the case of the second embodiment, the groove bottom forming member 13 is in the shape of a plate of a cross-sectional rectangle. The width of the groove bottom forming member 13 is slightly larger than the width of the groove 2, and both sides of the groove bottom forming member 13 are buried by the portions of the side wall 2b which are drawn to the bottom portions 2a of the side walls 2b. The bottom forming member 13 is reliably supported by the heat insulating main body 1. And thanks to the removal of both sides of the surface of the groove 2 opening side of the groove bottom forming member 13, the groove 2 is exposed. The linear part of the heat generating body 3 in the groove 2 is in linear contact with the surface of the groove bottom forming member 13, and most of the rest is exposed in the groove 2.

The heating unit of the second embodiment is manufactured in the same manner as in the first embodiment by the vacuum forming method. Also in this case, the groove bottom forming part 13 functions as a mask, and the heating unit in which the heat generating body 3 was exposed in the groove 2 is obtained. The material of the groove bottom forming member 13 may be generally the same as in the first embodiment, but in some cases, a low density molded article having many voids may be used. In this case, in particular, when a molded article containing a large number of cavities is used, the same heat dissipation effect as that of the air layer can be obtained in the heat generator 3 in contact with the groove bottom forming member 13.

Third embodiment

The surface finish facing the heat generating element 3 of the groove bottom forming member is not particularly limited, and may be flat as in the second embodiment, or may be formed in an uneven state. If the surface of the groove bottom forming member is uneven, the flatness and manufacturing effort are almost unchanged, but the contact area between the heat generating element 3 and the groove bottom forming member decreases due to the surface unevenness, and the heating element 3 is free. The surface becomes more and heat generation efficiency improves further.

FIG. 6 shows an embodiment (third embodiment) in which the surface of the groove bottom forming member 14 is formed with irregularities, and FIG. 7 shows the groove bottom forming bonsai 14.

In the third embodiment, the surface of the groove bottom forming member 14 is formed with irregularities having a cross-sectional waveform, and the heating element 3 exposed in the groove 2 is in contact with a part of the iron-shaped portion 15.

8 shows a modification of the groove bottom forming member 14 in the third embodiment.

In this case, by forming a plurality of grooves inclined to cross each other inclinedly on the surface of the groove bottom forming member 14, a plurality of columnar iron-shaped portions 16 are formed, and this surface is formed into an irregular shape. . And the heat generating body 3 contacts a part of this iron-shaped part 16. As shown in FIG.

Fourth embodiment

9 shows another embodiment (fourth embodiment) in which the surface of the groove bottom forming member 17 is formed unevenly.

In the fourth embodiment, a set of barbed wires 18 having a rectangular cross section is formed in the widthwise center of the surface exposed in the groove 2 of the plate-shaped groove bottom forming member 17, and the heating element exposed in the groove 2 is formed. (3) is in contact with the front of the steel bar (18). The steel bar 18 needs a certain width in order to form a shape with good self-reliability by the vacuum forming process.

The cross-sectional shape of the steel bar 18 is not limited to a square shape, and can be changed as appropriate. The number of steel bars 18 is not limited to one set, and may be two or more sets depending on the width of the heating element 3. This ensures the width of the barbed wire 18 sufficient as a whole. Such a groove bottom forming member 17 can be manufactured by the prior art.

Fifth Embodiment

10 shows the main part of the heating unit of the fifth embodiment.

In the case of the fifth embodiment, the groove bottom forming member 20 is composed of the groove bottom forming portion 21 which is the same plate shape as the groove bottom forming member 13 of the second embodiment, and the heating element supporting portions 22 disposed on both sides thereof. It is. The heating element support portion 22 is made separately from the groove bottom forming portion 21, the cross section is almost V-shaped, and the inner surface is shown as the concave surface 22a. The heating element support part 22 is embedded in the portion which is extended to the bottom 2a of both side walls 2b so as to face each other in the width direction of the concave surface 22a and the groove 2, and is integrally supported by the heat insulating main body 1. . Both curved portions 3a of the heat generating element 3 are strongly sandwiched by the bottom portion of the concave surface 22a of the heat generating element support portion 22, whereby the heat generating element 3 is integrally supported by the heat insulating main body 1. The width of the groove bottom forming portion 21 is almost equal to the width of the groove 2. The groove bottom forming portion 21 is sandwiched by the heating element supporting portions 22 on both sides, and is disposed on the bottom portion 2A so that the surface exposed to the opening side of the groove 2 contacts the heating element 3, and the heating element supporting portion 22 It is integrally supported by the heat generating body 3 by the heat insulation body 1.

The manufacturing method of the heating unit of the fifth embodiment will be described with reference to FIG. 3 described above. After the heating element 3 is placed on the mask member 7, the groove bottom forming portion 21 is placed on the heating element 3. Then, the heat generating body support part 22 is set in the curved part 3a of the heat generating body 3 which protrudes from the mask member 7 and the groove bottom forming part 21. As shown in FIG. Then, vacuum molding is performed in the same manner as in the first embodiment. At the time of vacuum forming, it acts as a mask of the groove bottom forming portion 21, prevents the deposition of ceramic fibers on the heating element 3, and also the heating element supporting portion 22 also acts as a mask, and the concave surface 22a. And the deposition of ceramic fibers on the curved portion 3a of the heating element 3 is prevented, the curved portion 3a is exposed in the heating element support portion 22 toward the groove 2, and substantially the entire surface of the heating element 3 is exposed. A heating unit exposed to the outside of the thermal insulation main body 1 is obtained. Since the curved part 3a of the heat generating body 3 is also exposed to the outer side of the heat insulation main body 1, this heating unit is excellent in the thermal radiation from the curved part 3a.

In the above embodiment, the groove bottom forming portion 21 and the heating element support portion 22 are made separately and are not joined to each other. However, after being aligned with the heating element 3, they may be joined to each other by appropriate means. Moreover, the groove bottom forming member 20 by which the groove bottom forming part 21 and the heat generating body support part 22 were integrated can also be used. In that case, the combination of the heating element 3 and the groove bottom forming member 20 is placed on the mask member 7 before vacuum forming.

The shape of the groove bottom forming portion 21 and the heating element support portion 22 is not limited to that of the fifth embodiment, and can be appropriately changed. For example, using the same thing as the groove bottom forming member 10, 14, 17 of 1st, 3rd, or 4th Example as the flaw bottom forming part 21, the heating unit which produces the same effect as the above is mentioned. It can be prepared in the same manner.

Sixth embodiment

11 and 12 show main parts of the heating unit of the sixth embodiment.

In the case of the sixth embodiment, the groove bottom forming member 23 is composed of a plurality of groove bottom forming pieces 24 having the same shape. The groove bottom forming piece 24 is shown in detail in FIG. The length of the groove 2 between the grooves 2 formed in the cross section of the groove bottom forming piece 24 integrally formed in the cross-sectional rectangular cross-section extending in the longitudinal direction of the groove 2 on both sides in the width direction. A wide yaw hole 26 extending in the direction is formed. The projection 27 for holding the width direction center part of the heat generating body 3 is integrally formed in the one end side part of the width direction center part of the bottom of the recessed part 26. As shown in FIG. The one side surface of the protrusion 27 is the same as the one end surface of the groove bottom forming piece 24, and the groove | channel 28 which is the cross section semicircle extended in the width direction is formed in the middle part of the height of the cross section of this protrusion 27. As shown in FIG. The opposite side surface of the protrusion 27 is formed in the semicircular cylindrical surface according to the shape of the groove | channel 28, and is located in the longitudinal direction rather than the cross section on the opposite side of the groove | channel bottom formation piece 24. As shown in FIG. The protrusion 25 protrudes higher than the barbed wire 25, and the bottom surface of the groove 28 is at substantially the same height as the front face of the barbed wire 25.

The pair of groove bottom forming pieces 24 are combined in a state in which the end faces on the groove 28 side are in close contact, and the combination as described above is a gap in the longitudinal direction of the groove 2 in a state in which the end faces are in close contact with each other in plural sets. Lined up without. The groove bottom forming piece 24 is integrally supported by the heat insulating main body 1 in the same manner as the groove bottom forming member 10 of the first embodiment.

The heat generating body 3 is the heat insulating body 1 in the curved part 3a of both sides, in the state which contacted the front surface of the iron bar 25 of both sides of the groove bottom forming piece 24 similarly to the case of 1st Example. It is integrally supported by the heat generating body 3, and the width direction center part of the heat generating body 3 is gripped through the cross-sectional circular opening formed by combining the groove | channel 28 of the projection 27 of a pair of groove | channel bottom formation piece 24. As shown in FIG. And the surface of the heat generating body 3 other than the part through the opening of the protrusion 27 is exposed between the both side walls 2b in the groove 2.

Such a configuration is effective for constraining deformation due to creep elongation of the heating element 3, especially when used at high temperatures.

In addition, the cross-sectional shape of the groove | channel 28 of the projection 27 may be made into the triangle, and the heat generating body 3 may be made to pass through the opening of the cross-sectional rectangle which combined the pair of groove | channel 28. In this way, in the opening, the heat generating element 3 is in line contact with the projection 27 at four places, and most of the remainder is exposed.

The manufacturing method of the heating unit of 6th Example is demonstrated with reference to FIG. 3 mentioned above, The position where the tip part of the processus | protrusion 27 of the groove bottom forming piece 24 fits on the upper surface of the mask member 7 is located. And a plurality of groove bottom forming pieces 24 combined with the heating element 3 are placed on the mask 7 so that the tip of the projection 27 is sandwiched in the above-described factor, and the same as in the case of the first embodiment. Perform vacuum molding.

In order to ensure the shape independence stability of the groove bottom forming piece 24 in the vacuum forming step, the projection 27 is usually formed on the groove bottom forming member 10 of the first embodiment as the groove bottom forming piece 24. It is suitable to use what has a shape. However, the configuration of the groove bottom forming piece 24 is not limited to the above embodiment, and can be changed as appropriate. Moreover, in the said Example, although the groove bottom forming member 23 is comprised by the some groove bottom forming piece 24 divided | segmented from each other, the whole groove bottom forming member is integrally formed, and the heat generating body (the You may form the protrusion which is arbitrary shape for holding the width direction center part of 3).

Seventh embodiment

14 and 15 show main parts of the heating unit of the seventh embodiment.

The groove bottom forming member 10 in the seventh embodiment is the same as that in the first embodiment. However, the depth of the recess 2 is deeper than in the case of the first embodiment, and the inner width of the recess 12 is almost equal to the width of the groove 2. The heat generator 3 is supported by the heat insulating body 1 in the same manner as in the first embodiment. And the bent part 3b which is iron-like is formed in the part of the exposed heat generating body 3 in the groove | channel 2 as if protruding in the recess 12 of the groove bottom formation member 10. As shown in FIG.

The manufacturing method of this heating unit is the same as that of each case mentioned above.

This structure is suitable for a heating unit of high output density because the density of the heating element 3 per unit area of the groove 2 is high.

The iron shape of the bent portion 3a of the heat generating element 3 is not particularly limited, and may be in the form of a mountain or a valley having a triangle or curvature, as shown in FIG.

Eighth embodiment

16 and 17 show main parts of the heating unit of the eighth embodiment.

In the eighth embodiment, the groove bottom forming member 10 and the first heating element 3 are integrally formed in the bottom portion 2a of the groove 2 of the heat insulating main body 1 as in the first embodiment. Supported. And a pair of spacer 30 is arrange | positioned at the opening side of the groove | channel 2 of the 1st heat generating body 3, and the 2nd heat generating body 31 is arrange | positioned at the opening side of the groove | channel 2 of the spacer 30 again. . The second heating element 31 has the same shape as the first heating element 3, and both curved portions 31a are embedded in portions of both sidewalls 2b of the groove 2 to be integral with the heat insulating main body 1. Is supported. The spacer 30 forms a columnar shape extending in the longitudinal direction of the groove 2, and is fitted to portions of both sidewalls 2b of the groove 2 in a state of being fitted in portions that are inclined to both sides of the two heating elements 3 and 31. It is embedded and is integrally supported by the heat insulating main body 1. Opposite surfaces of the spacers 30 are almost identical to both sidewalls 2b of the grooves 2. For example, the spacer 30 is a refractory agent, such as a ceramic fiber.

The manufacturing method of the heating unit of the eighth embodiment will be described with reference to FIG. 3 described above. A spacer is placed on a portion of the mask member 7 placed on both sides of the second heating element 31 and placed on both sides of the second heating element 31. 30 is placed, the first heating element 3 is placed thereon, and the groove bottom forming member 10 is placed thereon again. Then, vacuum molding is performed in the same manner as in the first embodiment. At the time of vacuum forming, as in the case of the first embodiment, the groove bottom forming member 10 acts as a mask, and deposits of ceramic fibers in the recess 12 and on the surface of the first heating element 3. Stop it. In addition, the spacer 30 maintains the distance between the two heating elements 3 and 31, acts as a mask, and prevents the deposition of ceramic fibers on the surface of the second heating element 31. Thereby, the heating unit by which the two heat generating bodies 3 and 31 were exposed in the groove | channel 2 is obtained.

The heating unit of the eighth embodiment is also suitable as a heating unit of high power density. There is no particular limitation on the arrangement relationship between the waveforms of the two heating elements 3 and 31, but it is necessary to shift the phases of the waveforms so that heat can be radiated freely on the surfaces of the two heating elements 3 and 31 as much as possible. It is particularly preferable that the absolute value of the phase is shifted by 90 degrees as shown in 180 degrees or 17 degrees.

The number of heating elements is not limited to two, and even if three or more heating elements are provided, they are completely the same. As a matter of course, the shape of the heating element does not need to be flat as in the above-described embodiment. For example, a curved portion in the width direction may be used as in the seventh embodiment.

Various modifications are possible without departing from the scope of the invention. The cross-sectional shape of the groove that is the heat insulating main body is not limited to a rectangle or a trapezoid, and may be a shape having a triangle, a polygon, or a curved surface, and the change in each of the above-described embodiments is easy. In addition, various changes in cross-sectional shape orthogonal to the width of the groove-bottom molding material, the spacer or the corrugated heating element can be made in response to this, and as a result, it is easy to select a preferred combination thereof, and none of the technical scope of the present invention. It is only a minor variation belonging to. Further, the present invention is also applicable to a heating unit manufactured by a method other than the vacuum forming method, for example, casting a refractory groove bottom forming member such as castable into a mold, and molding it integrally with the main casting body and the heating element. Can be.

1 is a perspective view of an essential part of a heating unit, showing a first embodiment of the present invention.

2 is an enlarged cross-sectional view taken along the line A-A of FIG.

3 is an intermediate abbreviated vertical sectional view of the manufacturing apparatus showing one example of a manufacturing process of the heating unit of the first embodiment.

4 is a sectional view of an essential part of a heating unit, showing a second embodiment of the present invention.

5 is a cross-sectional view taken along the line B-B in FIG.

6 is a sectional view of an essential part of a heating unit, showing a third embodiment of the present invention.

7 is a perspective view showing an example of a groove bottom forming member of the heating unit of the third embodiment.

8 is a perspective view showing a modification of the groove bottom forming member of the heating unit of the third embodiment.

9 is a sectional view of an essential part of a heating unit, showing a fourth embodiment of the present invention.

10 is a sectional view of an essential part of a heating unit, showing a fifth embodiment of the present invention.

11 is a sectional view of an essential part of a heating unit, showing a sixth embodiment of the present invention.

12 is an enlarged cross-sectional view of the C-C line of FIG.

13 is a perspective view showing an example of a groove bottom forming member of the heating unit of the sixth embodiment.

14 is a sectional view of an essential part of a heating unit, showing a seventh embodiment of the present invention.

15 is a cross-sectional view taken along the line D-D of FIG.

FIG. 16 is a sectional view of an essential part of a heating unit showing an eighth embodiment of the present invention; FIG.

17 is a cross-sectional view taken along the line E-E of FIG.

18 is a sectional view of an essential part of a heating unit, showing a conventional example.

19 is an enlarged cross-sectional view of the F-F line in FIG.

20 is a sectional view of an essential part of a heating unit, showing another conventional example.

21 is an intermediate abbreviated vertical sectional view of the manufacturing apparatus showing the manufacturing process of the heating unit of FIG.

<Explanation of symbols for the main parts of the drawings>

1: insulation

2: home

2a: bottom of groove

2b: sidewall of the groove

3, 31: heating element

3a, 31a: curved portion of the heating element

4: vacuum molding

7: mask member (groove forming part)

10, 13, 14, 17, 20, 23: groove bottom forming member

Claims (3)

The groove provided on the surface of the heat insulating body mainly composed of heat insulating material is provided with a heating element processed into a waveform having an amplitude larger than the width of the groove, wherein the curved portions on both sides in the width direction of the heat generating element enter the heat insulating body from both side walls of the groove. In the electric heating unit integrally supported by the main body, And a refractory groove bottom forming member which is made separately from the heat insulating main body and integrally supported by the heat insulating main body so that the surface of the groove opening side is exposed from the heat insulating main body by covering the bottom of the groove. The heating element is disposed on the groove opening side of the groove bottom forming member, is integrally supported by the heat insulating main body to be in contact with a part of the surface of the groove bottom forming member, and is exposed to the outside of the heat insulating main body in the groove. An electric heating unit. In the electric heating unit manufactured by vacuum forming and integrally supported with a heat generating body processed in a wave shape in a groove of a surface of a heat insulating molded article having a ceramic fiber as a main component, Among the amplitudes of the waveform of the heating element in the dimensional relationship of the cross section orthogonal to the steel part in the corrugated heating element placed at least partially in contact with the steel forming portion along the groove forming steel portion provided at the predetermined position of the vacuum forming die. A groove bottom forming member is formed in the insulating molded body by vacuum forming the refractory groove bottom forming member having an outer dimension covering the width of the heating element corresponding to the width, while contacting with a part of the heating element and not in contact with the steel part. An electric heating unit, characterized in that the heating element is integrally supported. In the method for producing an electric heating unit by vacuum molding in which a heating element processed in a wave shape is integrally supported in a groove on a surface of a heat-insulated molded body mainly composed of a ceramic fiber. At least a portion of the heating element formed in the vacuum forming die is formed along the groove forming steel groove, and at least a portion of the heating element is processed into a waveform so as to be in contact with the steel groove. By contacting a refractory groove bottom forming member having an outer dimension covering the corresponding portion of the heating element with a part of the heating element, and placing the insulating bottom body so as not to be in contact with the steel part, the insulating molded body is formed by the groove bottom forming member and A method for producing an electric heating unit, characterized in that the molding integrally with the heating element.