JP2019083219A - Electric heater, method of manufacturing electric heater and heating apparatus including the same - Google Patents

Abstract

To provide an electric heater capable of reducing heat capacity of an insulator and equalizing temperature distribution by reducing exposed area of the insulator to a heating space to improve response of temperature rise and drop, and to provide a method of manufacturing the electric heater, and a heating apparatus.SOLUTION: An electric heater comprises: a plate-like heating element 10 in which a current path is formed by forming a slit; and insulators 20 for supporting the heating element 10. The heating element 10 is supported by the insulators 20 at a pair of width direction end parts 13 and 13 located in a width direction X along the slit of the heating element 10. Each insulator 20 located at each of the width direction end parts 13 and 13 is divided into at least two parts to a horizontal direction along the width direction X. The width direction end parts 13 are respectively locked between divided elements 21 and 22, and fastening tools 30 for fastening the divided elements 21 and 22 at parts above the width direction end parts 13 are provided respectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric heater, a method of manufacturing the electric heater, and a heating apparatus. More specifically, a pair of plate-like heating elements having current paths formed by forming slits, and an insulator supporting the heating elements, and a pair of the heating elements positioned in the width direction along the slits The present invention relates to an electric heater supported by the insulator at a widthwise end, a method of manufacturing the electric heater, and a heating apparatus.

  Conventionally, as an electric heater as described above, for example, the one described in Patent Document 1 is known. In this electric heater, the insulator is divided into upper and lower parts in the vertical direction, and the heat generating element is locked therebetween. However, the forceps are divided up and down, and the fixing pin is vertically penetrated and fixed to these forceps. Therefore, the forceps are formed wider by the penetration of the fixing pin, and the heat capacity of the forceps is increased. Further, if the insulator is formed wide, the exposed area of the heating element to the heating space is reduced by that amount, the temperature distribution becomes nonuniform, and the heating efficiency is reduced. As a result of these, the response of temperature rise and fall is still insufficient.

Japanese Patent Application Laid-Open No. 2002-359061

  In view of such conventional circumstances, the present invention reduces the heat capacity of the insulator and reduces the exposed area of the insulator to the heating space to make the temperature distribution uniform and improve the response of temperature rise and fall. It is an object of the present invention to provide a manufacturing method of the

  In order to achieve the above object, the feature of the electric heater according to the present invention is provided with a plate-like heating element in which a current path is formed by forming a slit, and an insulator for supporting the heating element. Among the above, in the structure supported by the insulator at a pair of width direction ends located in the width direction along the slit, the heat generating body bends the end of the heat generating body toward the insulator at a bending portion And a bent portion obtained by bending the tip end portion of the width direction end in the direction along the width direction, and the tip end portion is directed to the other width direction end side The bent portion is engaged with the inside of the insulator in a bent state, and the bent portion is exposed to the heating space side.

  The insulator may have an elongated insulating member in a direction orthogonal to the width direction, and the bent portion may be locked to the insulating member. At least two sets of the heating elements may be provided, and the adjacent heating elements may be arranged in parallel. The bent portion may be formed by bending the tip end portion at a substantially right angle. The heating element may be formed flat. The heating element may be supported such that the width direction is along the horizontal direction.

  In order to achieve the above object, the feature of the method of manufacturing an electric heater according to the present invention comprises a plate-like heating element in which a current path is formed by forming a slit, and an insulator supporting the heating element In a method of manufacturing an electric heater supported by the insulator at a pair of widthwise end portions positioned in the width direction along the slit among the heating elements, the end portion of the heating element is directed to the insulator at a bending portion Forming the pair of widthwise end portions, bending the tip end portion of the widthwise end portion in a direction along the width direction to form a bent portion, and forming the tip end portion in the other widthwise end portion The bent portion is engaged with the inside of the insulator in a state of being bent toward the side, and the bent portion is exposed to the heating space side.

  The above-mentioned electric heater can be implemented as a heating device provided with this.

  According to the features of the electric heater and the method of manufacturing the electric heater and the heating device according to the present invention, the heat capacity of the insulator can be reduced and the exposed area of the insulator to the heating space can be reduced to improve the response of temperature rise and fall. It has become possible.

  Other objects, configurations, and effects of the present invention will be apparent from the following section of the embodiments of the present invention.

It is a front view of the electric heater concerning a first embodiment of the present invention. It is the sectional view on the AA line of FIG. It is a top view of the thin plate member before curving. It is the partial enlarged front view of the insulator vicinity. It is a front view which shows the modification of 1st embodiment. (A) is the FIG. 4 equivalent view which shows 2nd embodiment of this invention, (b) is the FIG. 4 equivalent view which shows the modification of (a). (A) is a partial expanded sectional view near the insulator in a third embodiment of the present invention, (b) is a partial expanded sectional view near the insulator showing a modification of (a). (A) is a top view of the thin plate member before curving in the third embodiment, (b) is a partially enlarged side view of the width direction end of the heating element in the third embodiment. It is the FIG. 4 equivalent view which shows 4th embodiment of this invention. It is the FIG. 4 equivalent view which shows the modification of 4th embodiment. It is the FIG. 4 equivalent view which shows 5th embodiment of this invention. (A) is the FIG. 4 equivalent view which shows 6th embodiment of this invention, (b) is the FIG. 4 equivalent view which shows 7th embodiment of this invention. It is the FIG. 4 equivalent view which shows other embodiment of this invention.

Next, a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the electric heater 1 according to the present invention includes a heating element 10 and a pair of insulators 20 and 20 for supporting the heating element 10. The pair of insulators 20 and 20 are located at both ends in the width direction X of the heat generating body 10, and are fixed to the fixing member 40 by the fasteners 30. The fixing member 40 is fixed to a frame 2 as a base material made of, for example, a steel material via a heat insulating member 3 such as a ceramic fiber. Further, a lead member 50 for supplying electric power to the heating element 10 is fixed to the fixing member 40 in a state of being electrically insulated from the frame 2.

  For example, as shown in FIG. 1, a supporting member 101 for suspending and supporting the inside of the furnace is provided on the electric heater 1 by welding or the like on the frame 2 to constitute a heating unit 100. The heating unit 100 is installed mainly on the ceiling of the furnace and is implemented as a heating device for heating an object to be heated which is introduced into the furnace.

  As shown in FIGS. 1 and 2, the heating element 10 is formed in a plate shape and a rectangular shape, and a serpentine current path 12 is formed by alternately cutting a plurality of slits 11 in the width direction X. As shown in FIG. 1, the space between the pair of widthwise end portions 13 and 13 of the heating element 10 is gently curved in the longitudinal direction Y orthogonal to the slit 11, and is on the lower side in the vertical direction Z (furnace inside) It has a convex shape. Further, the current path end portions 12 x and 12 y positioned at the end portions in the longitudinal direction Y of the heat generating body 10 are bent upward in the vertical direction Z and connected to the lead member 50.

  As shown in FIG. 3, the heating element 10 is made of, for example, a thin plate member 10 'made of a conductive material such as an Fe-Cr-Al alloy or a nickel-chromium alloy. The widthwise end portion 13 is formed by bending a pair of end portions 13 ′ and 13 ′ in the width direction X of the thin plate member 10 ′ toward the upper side in the vertical direction Z at the first bending portion 14 ′. Further, the bending portion 16 is formed by bending the tip end portion of the width direction end portion 13 outward of the thin plate member 10 ′ downward in the vertical direction Y by the second bending portion 15 ′. The heat generating element in each of the following embodiments is also the same material and constitution unless otherwise specified.

  As shown in FIGS. 1 and 4, the insulator 20 includes a first divided body 21 and a second divided body 22 which are divided in the horizontal direction along the width direction X. The first and second divided bodies 21 and 22 are made of a so-called ceramic material or silicon nitride material mainly composed of alumina, alumina-silica, mullite, zircon or cordierite, and the heating element 10 and the frame 2 And electrically isolated from. The insulator and each divided body in each of the following embodiments are also the same material and constitution unless otherwise specified.

  The first and second divided bodies 21 and 22 are formed in a long shape in a longitudinal direction Y orthogonal to the width direction X. By dividing the insulator 20 in the horizontal direction, the divided members 21 and 22 can be formed narrower in the width direction X. As a result, the heat capacity of the entire insulator 20 can be suppressed, and the temperature distribution to the heating space can be made uniform, and the response of the temperature rise and fall can be improved. Further, by forming the divided bodies 21 and 22 to be narrow, the exposed area of the insulator 20 with respect to the heating space S (inside of the furnace) below the vertical direction Z can be reduced.

  As shown in FIG. 4, the first divided body 21 has a substantially plate-like shape, and a curved portion 23 which curves toward the heating element 10 is formed. A notch 24 is formed on one side (the first divided body 21 side) of the second divided body 22. The notch portion 24 is opened to face the curved portion 23 of the first divided body 21. A protrusion 25 slightly protruding toward the first divided body 21 is provided in the lower part of the notch 24, and a gap 26 is formed between the protrusion 25 and the first divided body 21 so that the thickness of the heating element 10 is large. It is formed wider. Moreover, the through-hole 27 which penetrates the below-mentioned fastener 30 is formed in the 1st, 2nd division bodies 21 and 22. As shown in FIG. The through hole 27 is provided above the curved portion 23 and the notch 24.

  Here, the bent portion 16 of the widthwise end 13 is engaged with the notch 24 of the second divided body 22. The movement of the second bent portion 15 of the width direction end portion 13 to the heat generating body 10 side is restricted by the curved portion 23 of the first divided body 21. On the other hand, movement of the bending portion 16 to the other side is restricted by the notch portion 24. In addition, the air gap 26 restricts the movement of the heat generating body 10 in the width direction X and prevents the falling of the width direction end 13.

  As described above, by sandwiching the end portion 13 in the width direction between the curved portion 23 and the notch portion 24, the heating element 10 is locked between the first and second divided members 21 and 22. Thereby, the curved portion 23, the notch portion 24 and the air gap 26 combine to restrict the movement in the width direction X due to the thermal deformation at the time of heat generation and cooling of the heat generating body 10, and the falling off from the insulating body 20. To prevent. Furthermore, since the first bent portion 14 of the heat generating body 10 is located below the insulator 20, the first divided body 21 is supported relative to the heating space so as to cover the heat generating body 10, and the heating space of the insulator 20 is Can further reduce the exposed parts.

  The fastener 30 penetrates the divided bodies 21 and 22 in the width direction X, and fastens and fixes the divided bodies 21 and 22 to the fixing member 40. Since the fastener 30 is positioned above the widthwise end 13 by the through hole 27, the fastener 30 does not prevent the heat radiation from the heating element 10. Moreover, since the fastener 30 fastens the divided members 21 and 22 in the width direction X, the insulator 20 can be formed to be narrower, and the heat capacity of the insulator 20 can be suppressed. As the fastener 30, for example, a bolt 31 as a rod-like member is used.

  As shown in FIG. 1, the fixing member 40 is, for example, a channel member in which a plate-like object is formed in a channel shape, and is fixed to the frame 2 by attachment means 41 such as bolts, screws or welding. Further, the lead member 50 is made of a thin plate member substantially the same as the heating element 10, and is fixed by the fixing tool 52 in a state of being electrically insulated from the frame 2 through the insulating member 51 such as insulator.

Here, the assembly manufacturing procedure of the electric heater 1 in this embodiment is demonstrated.
First, the curved portion 23 of the first divided body 21 and the cutout portion 24 of the second divided body 22 are fitted into the fixing member 40 fixed in advance to the frame 2 so as to face each other. Next, the bolt 31 is penetrated through the through holes 27 of the divided members 21 and 22 and fastened and fixed to the fixing member 40 by the nut 32. Then, the width direction end 13 of the heat generating body 10 is inserted in the longitudinal direction Y through the air gap 26 in the notch 24. Thereby, the width direction end 13 is locked between the first and second divided bodies 21 and 22, and the heat generating body 10 is suspended and supported on the insulator 20.

In the present embodiment, the electric heater 1 is constituted by a single heating element 10, but may be constituted by a plurality of heating elements 10.
For example, an electric heater 1A according to a modification as shown in FIG. 5 includes a plurality of heating elements 10 arranged in parallel, and the above-described insulator 20 and the respective heating elements on the outermost side in the width direction X of this heating element group. A second insulator 20A is provided between ten. The second insulator 20A includes the first divided body 21 and the second divided body 22A sandwiched between the pair of first divided bodies 21 and 21. The first divided body 21 is disposed symmetrically with respect to the second divided body 22A.

  The second divided body 22A has a substantially T-like shape, and the notches 24 are respectively formed on both side surfaces (the first divided bodies 21 and 21 sides). Further, a through hole 27A communicating with the through hole 27 of the first divided body 21 is formed in the second divided body 22A. The bolts 31 penetrate the through holes 27 and 27A to fasten and fix the first divided bodies 21 and the second divided bodies 22A to the fixing member 40.

  Here, it is also possible to use the insulator 20 as the second insulator 20A. However, in such a case, since the second divided members 22 located on the outer side in the width direction X with respect to the heating element 10 overlap between the heating elements 10, the heat capacity of the insulator increases accordingly. Moreover, it is also difficult to arrange the adjacent heating elements 10 in close proximity. On the other hand, the second insulator 20A shares the second divided body 22A between the adjacent two sets of heating elements 10. Thereby, the second insulator 20A can be formed narrow in the width direction X, and the heat capacity of the second insulator 20A can be suppressed. In addition, the widthwise end portions 13 of the adjacent heating elements 10 can be disposed closer to each other, and the heating elements 10 can be disposed densely in the width direction X. Therefore, the heating surface density with respect to the heating space can be increased, the temperature distribution can be made uniform, and the response of temperature rise and fall can be improved.

  In the modification shown in FIG. 5, four heating elements 10 are arranged in parallel, but the number of heating elements 10 is not limited to this. Moreover, in the modification of the said 1st embodiment, although the heat generating body 10 was electrically connected in series between the lead members 50 and 50, it is also possible to connect in parallel.

  Next, another embodiment of the present invention will be described. In the following embodiments, the same members as those in the first embodiment are given the same reference numerals, and parts different from the above embodiment will be mainly described.

  In the second embodiment shown in FIG. 6 (a), the shape of the width direction end of the heat generating element and the insulator are different from those of the first embodiment. In the electric heater 1A according to the second embodiment, the width direction end 13A of the heat generating body 10A is formed to be oriented downward in the vertical direction Y by the first bending portion 14A.

  The insulator 20B is composed of a pair of a first divided body 21B and a second divided body 22B. The first divided body 21B has a plate shape, and an inclined portion 23B is formed at the lower end thereof. The inclined portion 23B is inclined at an acute angle with respect to the vertical direction Z along the heating element 10A. On the other hand, the second divided body 22B has a substantially J-like shape, and on the first divided body 21B side, the groove portion 24B and the projecting portion 25B protruding to the inclined portion 23B are formed. An air gap 26B wider than the thickness of the heat generating body 10A is formed between the projecting portion 25B and the inclined portion 23B.

  In this embodiment, the heat generating body 10A is locked between the first and second divided bodies 21B and 22B by sandwiching the width direction end 13A of the heat generating body 10A with the inclined portion 23B and the groove 24B. Thereby, the inclined portion 23B, the groove portion 24B and the air gap 26B combine to restrict the movement in the width direction X due to the thermal deformation at the time of heat generation and cooling of the heat generating body 10A, preventing the insulation member 20 from falling off Do.

  As described above, also in the electric heater 1A according to the second embodiment, the divided bodies 21B and 22B can be formed to be narrow as in the first embodiment, and the heat capacity of the insulator 20B can be suppressed. Can. Further, by forming the insulator 20B to be narrow, exposed portions of the divided bodies 21B and 22B to the heating space side can be reduced, temperature distribution can be made uniform, and response of temperature rise and fall can be improved. Become.

Here, also in the second embodiment, as in the modification of the first embodiment, it is possible to arrange a plurality of heating elements in parallel.
In the electric heater 1C according to the modification of the second embodiment, as shown in FIG. 6 (b), the second insulator 20C is provided between the respective heating elements 10A arranged in parallel. The second insulator 20C includes the first divided body 21B of the second embodiment described above and a second divided body 22C sandwiched between the pair of first divided bodies 21B and 21B.

  The second divided body 22C is substantially T-shaped, and a protrusion 25C protruding toward the groove 24C and the inclined portion 23B is formed on both side surfaces (sides of the first divided bodies 21B and 21B). Further, a through hole 27C communicating with the through hole 27B of the first divided body 21B is formed in the second divided body 22C.

  Also in this modification, as in the modification of the first embodiment, the second divided body 22C is shared between the adjacent heating elements 10B. Thus, the insulator 20C can be formed to be narrow, and the heat capacity of the entire insulator 20C can be suppressed. In addition, it is possible to increase the heating surface density with respect to the heating space, and it is possible to improve the response of temperature rise and fall.

  In the third embodiment shown in FIGS. 7 and 8, the configurations of the heating element and the insulator are different from those of the above-described embodiments. As shown to Fig.7 (a), electric heater 1D which concerns on 3rd embodiment is a heat sink 10B, a pair of division | segmentation body 61, 61, and a bushing as an insulator inserted in this pair of division | segmentation body 61, 61. And an insulator 60.

  In the heating element 10B, a plurality of substantially circular through holes 17 are formed at appropriate intervals between the pair of width direction end portions 13B and 13B. As shown in FIG. 8, between the pair of width direction end portions 13B and 13B in the heat generating body 10B, a gentle arc shape (arch shape) is formed in a longitudinal direction Y orthogonal to the slit 11. , Has a convex shape on the lower side (inside of the furnace). When the heat generating body 10B is softened by heat generation and thermally expanded, the weight of the heat generating body 10B acts in the vertical direction Z, and the shape becomes a catenary curve. This shape is mechanically stable, and even if it is softened, the shape of the heating element 10B is maintained and the detachment is prevented.

  As shown in FIG. 8, the heat generating body 10B is manufactured by forming the above-mentioned slits 11 in the thin plate member 10 'and forming the through holes 17 in the pair of end portions 13' 13 'in the width direction X. . The width direction end 13B is formed into an arc shape along the width direction X along the entire thin plate member 10 'and the end 13' is bent to the inside of the arc formed by the thin plate member 10 'at the first bending portion 14'. It is formed. Here, bending inward of the arc means orienting both widthwise end portions 13B and 13B parallel to each other along the substantially vertical direction Z. With this configuration, even if the heat generating element is softened by heating, the heat generating element 10B is vertically supported by the width direction end portions 13B and 13B, and an unnecessary stress is not generated in the support portion.

  As shown in FIG. 7A, a recess 63 is formed in the lower portion of the divided body 61, and a through hole 64 for allowing the bushing 62 to penetrate is formed in the recess 63. Further, a second through hole 65 through which a bolt 31 as the fastener 30 passes is formed in the upper portion of the divided body 61. The divided body 61 and the bushing 62 are made of the same insulating material as that in each of the above-described embodiments, and electrically insulate the heating element 10B from the frames 2 and 2 '. The pair of divided members 61, 61 are fixed to the fixing member 40 by the bolt 31 and the nut 32, with the recessed portions 63, 63 facing each other. Thereby, the groove 66 into which the width direction end 13B of the heat generating body 10B is inserted is formed in the vertical direction Z.

Here, the assembly manufacturing procedure of electric heater 1D in this embodiment is demonstrated.
First, the pair of divided members 61, 61 are opposed to each other to form a groove 66 into which the widthwise end 13B of the heat generating body 10B is inserted. The widthwise end 13B of the heat generator 10B is inserted into the groove 66 from below. After the insertion, the heat pipe 62 is inserted into and connected to the through hole 17 of the heating element 10B and the through holes 64, 64 of the pair of divided members 61, 61. These coupled members are fitted into the fixing member 40 previously attached to the frame 2, and the split bodies 61 and 61 are fastened and fixed by the fastener 30. As a result, the widthwise end 13 B is locked to the bushing 62 in the groove 66, and the heat generating body 10 B is suspended from the insulator 60.

  Also in the present embodiment, as in the above-described embodiments, the divided members 21B and 22B can be formed to be narrow, and the heat capacity of the insulator 60 can be suppressed. In addition, by forming the width narrowly, it is possible to reduce the exposed portions of the divided bodies 61, 61 to the heating space side, and it becomes possible to make the temperature distribution uniform and improve the response of temperature rise and fall. Furthermore, since the first bent portion 14B is located below the insulator 60, one split body 61 is supported relative to the heating space S so as to cover the heating element 10B, and the exposed portion of the insulator 60 with respect to the heating space S Can be further reduced.

Here, also in the third embodiment, it is possible to arrange a plurality of heating elements in parallel as in the modification of each of the above embodiments.
In the electric heater 1E according to the modification of the third embodiment, as shown in FIG. 7 (b), the second insulator 60A is provided between the heat generating members 10B arranged in parallel. The second insulator 60A includes the above-described divided bodies 61, 61 and a second divided body 67 sandwiched between the pair of divided bodies 61, 61.

  Recesses 68 are respectively formed on both side surfaces in the width direction X of the second divided body 67. In the recess 68, a through hole 69a is formed, which is in communication with the through holes 64, 64 of the divided bodies 61, 61 and allows the bushing 62 to pass therethrough. Further, a second through hole 69b communicating with the second through holes 65, 65 of the divided bodies 61, 61 is formed in the upper part thereof.

  By inserting the heat pipe 62 into the through holes 64, 69a of the divided body 61, 61 and the second divided body 67 and the through holes 17 of the heat generating body 10E, the heat generating body 10B is locked to the second insulator 60A. The heating elements 10B are arranged in parallel. Also in this modification, since the second divided body 67 located on the outer side in the width direction X with respect to the heating element 10B is common, the second insulator 60A can be configured to be narrow, and the heat capacity of the second insulator 60A can be reduced. It can be suppressed. Moreover, the heating surface density with respect to the heating space S can be increased, and the temperature distribution can be made uniform, and the response of the temperature rise and fall can be improved.

  In the fourth embodiment shown in FIGS. 9 and 10, the configurations of the heating element and the insulator are different from those of the above-described embodiments. As shown in FIG. 9, an electric heater 1F according to the fourth embodiment includes a plurality of heating elements 10C, an integral insulator 70 to which these heating elements 10C are attached, and an insulator 70 fixed to the frame 2 And a fixing member 40A to be attached.

  The heating element 10 </ b> C has the slits 11 formed in the same manner as each of the above-described embodiments and is formed in a substantially arc shape convex downward. Unlike the above embodiments, the width direction end 13C of the heat generating body 10C is not bent. A through hole 17 for allowing the through member 80 to pass therethrough is formed in the width direction end 13C. In addition, the fixing member 40A is formed in a substantially L shape in the longitudinal direction Y view.

  The insulator 70 has a plate-like shape as a whole, and includes a longitudinal portion 71 and a lateral portion 72 bent at least in the width direction X from the longitudinal portion 71. The vertical portion 71 is formed with a through hole 73 through which the above-described fastener 30 passes. The horizontal portion 72 is inclined at an acute angle with respect to the vertical direction Z along the heating element 10C, and a second through hole 74 is formed to allow the penetrating member 80 to pass therethrough. Thus, the volume of the whole insulator 70 can be reduced by continuously and integrally forming the horizontal part 72 to which the heating element 10C is attached from the vertical part 71, and the heat capacity of the insulator 70 can be suppressed. It becomes possible. In addition, the lateral portion 72 may be formed so as to be attachable to the width direction end portion 13C, and the lateral portion 72 can be formed narrow in the width direction X. Thereby, the exposure of the horizontal portion 72 to the heating space S side can be reduced, and the heating surface density can be improved to make the temperature distribution uniform and improve the heating efficiency. For the through member 80, for example, a bolt 81 is used.

Here, attachment of the heat generating body 10C to the insulator 70 will be described.
The bolt 81 passes through the through hole 74 of the lateral portion 72 and the through hole 17 of the heating element 10C, and attaches the end 13C in the width direction to the lower surface 72a of the lateral portion 72 with a nut 82. Here, it is also possible to attach it to the upper surface 72b of the lateral portion 72, as in the case of a heating element 10C 'indicated by the one-dot chain line in FIG. However, by attaching to the lower surface 72a side of the lateral part 72, the heating element 10C can be positioned so as to cover the lateral part 72 with respect to the heating space, and the exposed part on the heating surface side of the insulator 70 can be reduced. it can. In addition, adjacent heating elements 10C can be disposed close to each other, and the heating surface density can be improved. Therefore, in these points, the embodiment in which the heating element 10C is attached to the lower surface 72a is better.

In the present embodiment, the horizontal portion 72 is formed by bending the vertical portion 71 at an acute angle with respect to the vertical direction Z, but the inclination angle of the horizontal portion 72 is not limited to the above embodiment.
For example, an electric heater 1G according to a first modification of the fourth embodiment shown in FIG. 10A includes an insulator 70A having a lateral portion 72A bent at an obtuse angle with respect to the vertical direction Z. A heat generating body 10D which is gently curved in a convex shape upward in the vertical direction Z is attached to the horizontal portion 72A. An electric heater 1H according to a second modification shown in FIG. 7B includes an insulator 70B having a horizontal portion 72B bent approximately horizontally. A flat heating element 10E is attached to the horizontal portion 72B.

  Moreover, in the said 4th embodiment, the insulator 70 was each provided in the width direction edge part of a pair of each heat generating body, and the heat generating body was arranged in parallel. However, in addition to the aspect in which the pair of the insulators 70 is provided in line symmetry with respect to the vertical direction Z between the adjacent heating elements, it is also possible to use the second insulator 70C. For example, as shown in FIG. 10C, in the electric heater 1J according to the third modification, the second insulator 70C is composed of a longitudinal portion 71C and a pair of lateral portions 72C and 72C branched from the longitudinal portion 71C. . As a result, since the vertical portions 71C are common to the adjacent heating elements 10C, the insulator 70 can be formed narrower, and the surface density can be further improved.

  The electric heater 1K according to the fifth embodiment shown in FIG. 11 is different from the fourth embodiment in that an insulating pin 83 is provided instead of the bolt 81 as the penetrating member 80. Further, unlike the fourth embodiment, no through hole is provided in the lateral portion 72D of the insulator 70D.

  The insulating pin 83 is attached to penetrate the through hole 42 of the fixing member 40B in the vertical direction Z. The heat generating body 10C is attached to the lateral portion 72D by allowing the insulating pin 83 to penetrate through the through hole 17 of the heat generating body 10C while the widthwise end 13C is mounted on the upper surface 72b of the lateral portion 72D. Thereby, movement of the heat generating body in the width direction X due to thermal deformation is restricted, and the lateral portion 72D also prevents the heat generating body 10C from falling. Moreover, it is not necessary to form a plurality of through holes corresponding to the through holes 17 of the heat generating body 10C in the lateral portion 72D, and the processing of the insulator becomes easy.

  In 6th embodiment shown to Fig.12 (a), the structures of an insulator and a fixing member differ from said each embodiment. The electric heater 1L according to the sixth embodiment includes a plurality of heating elements 10F, an insulator 90, and a fixing member 40D that holds the insulator 90.

  The heating element 10F has the same configuration as that of the third embodiment, but the through hole 17 is not formed in the widthwise end 13F. For example, the fixing member 40D is formed into a tubular shape by bending a plate-like object such as a stainless steel plate into a substantially rectangular shape, and an opening 43 is formed along the longitudinal direction Y on the side surface 44 on the heating element 10F side. Since the fixing member 40D is formed by bending a plate-like object, the fixing member 40D can be thinned, and the heat capacity of the fixing member 40D can be suppressed. An insulator 90 is fitted in the longitudinal direction Y inside the fixing member 40D.

  The insulator 90 comprises a pair of first and second divided bodies 91 and 92. The first divided body 91 is substantially L-shaped, and includes a horizontal portion 93 along the width direction X and a vertical portion 94 continuous downward from the horizontal portion 93 in the vertical direction Z. At the lower end of the vertical portion 94, an inclined surface 94a is formed along the heating element 10F.

  The second divided body 92 is substantially L-shaped, and includes a vertical portion 95 extending in the vertical direction Z and a horizontal portion 96 continuing in the horizontal direction from the vertical portion 95 and supported by the lower portion 45 of the fixing member 40C There is. An inclined surface 96 a along the heating element 10 F is formed on the upper surface of the horizontal portion 96.

  The first and second divided bodies 91 and 92 are fitted and fixed to the inside of the fixing member 40D, and the groove 97 for inserting the width direction end 13F by the first and second divided bodies 91 and 92 in the vertical direction Z It is formed. One end of the groove 97 is in communication with the opening 43 as well as an air gap 97a formed by the inclined surfaces 94a and 96a.

  Thus, since the insulator 90 is comprised by the 1st, 2nd division body 91 and 92, the groove part 97 holding the width direction edge part 13F of the heat generating body 10F can be formed easily. Further, since the first and second divided bodies 91 and 92 are fitted into and fixed to the tubular fixing member 40D, it is sufficient that each of the divided bodies 91 and 92 has a thickness that can ensure at least insulation. The entire portion 90 can be formed narrow in the width direction X. Thereby, the heat capacity of insulator 90 can be controlled. Moreover, since the divided members 91 and 92 of the insulator 90 are thinly formed and fitted in and fixed to the tubular fixing member 40D, the portion exposed to the heating space S side of the insulator 90 can be reduced, and heating can be performed. The areal density can be improved. Therefore, the temperature distribution can be made uniform and the response of temperature rise and fall can be improved. Furthermore, the insulator 90 may be inserted in the longitudinal direction Y, and the fixing operation can be easily performed.

  Here, the widthwise end 13F is inserted into the groove 97 and held. The first bent portion 14F of the widthwise end 13F is sandwiched by the inclined surfaces 94a and 96a of the first and second divided bodies 91 and 92. As a result, the inclined surfaces 94a and 96a and the groove 97 cooperate to restrict movement of the heat generating body 10F in the width direction X due to thermal deformation at the time of heat generation and cooling, and to prevent falling off from the insulator 90 Do.

The electric heater 1M according to the seventh embodiment shown in FIG. 12 (b) is different from the sixth embodiment in the shapes of the heating element 10G, the insulator 90A and the fixing member 40E.
The heating element 10G is gently curved in a convex shape downward in the vertical direction Z. The widthwise end 13G is formed by bending the end of the heat generating body 10G in a semicircular shape toward the heat generating body 10G at the first bending portion 14G so as to be oriented in the width direction X. The fixing member 40 </ b> E has an opening 43 formed in the lower surface 45 along the longitudinal direction Y.

  The insulator 90A comprises a pair of first and second divided bodies 91A and 92A. The first divided body 91A is substantially L-shaped and includes a horizontal portion 93A along the width direction X and a vertical portion 94A continuous from the horizontal portion 93A in the vertical direction Z, and is supported by the lower portion 45 of the fixing member 40E. ing. A curved surface 93Aa is formed at one end of the horizontal portion 93A along the first bent portion 14G of the heat generating body 10F.

  The second divided body 92A is substantially L-shaped, and includes a vertical portion 95A along the vertical direction Z and a horizontal portion 96A continuous from the vertical portion 95A in the horizontal direction X. The first and second divided bodies 91A and 92A are fitted and fixed to the inside of the fixing member 40E, and the groove 97 for inserting the width direction end 13G by the first and second divided bodies 91A and 92A in the horizontal direction X It is formed. One end of the groove 97 is in communication with the opening 43 as well as a gap 97a formed by the curved surface 93Aa and the vertical portion 95A.

  Also in the present embodiment, as in the sixth embodiment, the groove 97 for holding the width direction end 13G of the heat generating body 10G can be easily formed, and the entire insulator 90A can be formed narrow. . Thus, the heat capacity of the insulator 90A can be suppressed, and the response can be improved. Furthermore, in the present embodiment, since the width direction end 13G is oriented in the width direction X, the first divided body 91A is positioned above the heating element 10G. Therefore, the first divided body 91A is not exposed to the heating space S, and the exposed area of the insulator 90A can be further reduced.

  Here, the widthwise end 13G is inserted into the groove 97 and held. The first bent portion 14G of the width direction end 13G is sandwiched by the curved surface 93Aa and the vertical portion 95A of the first divided body 91A. Thereby, the curved surface 93Aa, the vertical portion 95A and the groove portion 97A together regulate the movement in the width direction X due to the thermal deformation at the time of heat generation and cooling of the heat generating body 10G, and the falling off from the insulator 90A. To prevent.

Finally, the possibilities of further embodiments of the invention will be described.
In the first and second embodiments, the shape of the width direction end of the heat generating element is not limited to the above shape. For example, as shown in FIGS. 13A to 13D, the end of the widthwise end 13 may be bent substantially at right angles to form a bent portion 16 ′.

  The bending direction of the bending portion 16 ′ may be any direction as long as it is a horizontal direction along the width direction X. However, as shown in FIGS. 13 (b) and 13 (c), by orienting the bent portion 16 'to the heating element 10 side, one divided body is not exposed to the heating space S, and the insulator The exposed portion to the heating space S of 20 can be reduced. Thereby, the response of temperature rise and fall can be further improved. Further, in the aspect in which the heating elements 10 are arranged in parallel as shown in FIG. 6C, the adjacent heating elements 10 can be further approached. Moreover, it is possible to reduce the exposed portion of the second divided body 22c to the heating space S, and the heating surface density can be further improved.

  In the first and second embodiments, the shape of the insulator is not limited to the above. For example, as shown in FIGS. 13 (a) and 13 (d), the thickness of the first divided body 21a may be substantially constant and bent. Thereby, the heat capacity of the first divided body 21a can be further reduced.

  Further, in the first and second embodiments, the heating element is formed to be convexly curved downward. However, it is also possible to apply to a heating element which is convex on the upper side or a heating element formed flat. In the case of the second embodiment, the inclined portions 23D and 23E may be inclined at an obtuse angle or perpendicular or the like with respect to the vertical direction Z in accordance with the shape of the heating element.

  In the third embodiment, the heating element 10B is suspended and supported between the pair of divided members 61, 61 by the bushing 62 as an insulator. However, instead of the bushing 62, an adhesive may be filled and cured in the groove 66 to suspend and support the heating element 10B between the pair of divided members 61, 61. Moreover, in the said 4th-7th embodiment, the aspect of the parallel arrangement | positioning of the heat generating body was demonstrated to the example. However, by providing an insulator at each of the pair of widthwise end portions of the heating element, it is possible to constitute an electric heater by a single heating element.

  In the sixth and seventh embodiments, the insulator 90 is constituted by the first and second divided bodies 91 and 92. However, the present invention is not limited to such an aspect, and the insulator 90 may be formed as an integral body. However, in such a case, it is necessary to form the groove in order to form the groove for inserting the end of the heat generating member, and the sixth and seventh embodiments are superior in terms of the reduction of the heat capacity.

  The electric heater according to the present invention can be used, for example, as a heater for heat treatment of an object to be heated such as glass, ceramic, or metal. Further, this electric heater can be installed as a heating unit, for example, in a furnace and used as a heating device. In addition, the electric heater, the method of manufacturing the electric heater, and the heating apparatus can be applied to, for example, a semiconductor manufacturing apparatus for a semiconductor wafer, a substrate processing apparatus for heating a glass substrate, and the like.

1, 1A to 1M, 1 ': electric heater, 2, 2': frame (substrate), 3: heat insulation member, 10, 10A to 10M: heating element, 10 ': thin plate member, 11: slit, 12: current Path, 12x, 12y: Current path end, 13, 13A to 13M: Width direction end, 13 ': End, 14, 14A to 14M, 14': first bending portion 15, 15 ': second bending Part, 16, 16 ': bent part, 17: through hole, 20, 20A to 20C, 20a to 20d: insulator, 21, 21A, 21B, 21a, 21b: first divided body, 22, 22A to 22C, 22a to 22d: second divided body, 23: curved portion, 23B, 23C: inclined portion, 24: notch, 24A to 24C: groove, 25, 25A to 25C: projecting portion, 26, 26A to 26C: void, 27 , 27A to 27C: through holes, 30: fasteners (bolts) 31: Bolt, 32: Nut, 40, 40A to 40E: Fixing member, 41: Mounting means, 42: Through hole, 43: Opening, 44: Side, 45: Lower surface, 50: Lead member, 51: Insulating member, 52: Fixing device, 60, 60A: Insulator, 61: Divided body (Laser), 62: Agate, 63: Recess, 64: Through hole, 65: Second through hole, 66: Groove, 67: Second divided body , 68: recess, 69a: through hole, 69b: second through hole, 70, 70A to 70D: insulator, 71, 71C: vertical portion, 72, 72A to 72D: horizontal portion, 72a: lower surface, 72b: upper surface, 73: through hole, 74: second through hole, 80: through member, 81: bolt, 82: nut, 90, 90A: insulator, 91, 91A: first divided body, 92, 92A: second divided body, 93, 93A: horizontal part, 93Aa: curved surface, 94, 94A: lead Part, 94a: inclined surface, 95, 95A: vertical part, 96, 96A: horizontal part, 96a: inclined surface, 97: groove part, 97a: one end (void), 100, 100A to 100C: heating unit, 101: support member , S: heating space, X: width direction, Y: longitudinal direction, Z: vertical direction

Claims (1)

An electric heater comprising: a plate-like heating element in which a current path is formed by forming a slit; and an insulator supporting the heating element, wherein a part of the heating element is located inside the insulator.

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