WO2022137769A1

WO2022137769A1 - Heating device

Info

Publication number: WO2022137769A1
Application number: PCT/JP2021/039094
Authority: WO
Inventors: 一平鈴木
Original assignee: 京セラ株式会社
Priority date: 2020-12-25
Filing date: 2021-10-22
Publication date: 2022-06-30

Abstract

This heating device has a heating plate and a plurality of heaters. The heating plate has a heating surface and comprises a plurality of recess sections on a rear surface on the opposite side of the heating surface. The plurality of heaters are respectively positioned in a plurality of recess sections.

Description

Heating device

The disclosed embodiment relates to a heating device.

Patent Document 1 discloses a heating device in which a plurality of heaters are arranged so as to be parallel to the heating surface of the mold by inserting a plurality of heaters into a plurality of holes formed on the side surface of the mold.

JP-A-2017-154409

The heating device according to one embodiment has a heating plate and a plurality of heaters. The heating plate has a heating surface and has a plurality of recesses on the back surface opposite to the heating surface. The plurality of heaters are located in each of the plurality of recesses.

FIG. 1 is a side view of the heating device according to the first embodiment. FIG. 2 is a top view of the heating device according to the first embodiment. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. FIG. 5 is a cross-sectional view of the heating device according to the first modification of the first embodiment. FIG. 6 is a side view of the heating device according to the second modification of the first embodiment. FIG. 7 is a cross-sectional view of the heating device according to the second modification of the first embodiment. FIG. 8 is a side view of the heating device according to the second embodiment. FIG. 9 is a top view of the heating device according to the second embodiment. FIG. 10 is a cross-sectional view taken along the line XX of FIG. FIG. 11 is a cross-sectional view of the heating device according to the first modification of the second embodiment. FIG. 12 is a cross-sectional view of the heating device according to the second modification of the second embodiment. FIG. 13 is a cross-sectional view of the heating device according to the third modification of the second embodiment. FIG. 14 is a cross-sectional view of the heating device according to the third embodiment. FIG. 15 is a cross-sectional view of the heating device according to the fourth embodiment. FIG. 16 is a side view of the heating device according to the fifth embodiment. FIG. 17 is a cross-sectional view of the heating device according to the fifth embodiment. FIG. 18 is a side view of the heating device according to the sixth embodiment. FIG. 19 is a cross-sectional view of the heating device according to the sixth embodiment.

Hereinafter, embodiments of the heating device disclosed in the present application will be described with reference to the attached drawings. The present disclosure is not limited to the embodiments shown below. In addition, it should be noted that the drawings are schematic, and the relationship between the dimensions of each element, the ratio of each element, etc. may differ from the reality. Further, even between the drawings, there may be a portion where the relationship and ratio of the dimensions of the drawings are different from each other.

Further, in the embodiments shown below, expressions such as "constant", "orthogonal", "vertical" or "parallel" may be used, but these expressions are strictly "constant", "orthogonal" and "orthogonal". It does not have to be "vertical" or "parallel". That is, each of the above expressions allows for deviations in manufacturing accuracy, installation accuracy, and the like.

<First Embodiment>
FIG. 1 is a side view of the heating device 100 according to the first embodiment. FIG. 2 is a top view of the heating device 100 according to the first embodiment. In the following description, when the heating device 100 is brought into contact with the object to be heated, the surface located on the side of the object to be heated is the "upper surface", and the surface located on the side opposite to the object to be heated is the "lower surface". And. However, the heating device 100 may be used, for example, upside down, and may be used in any posture.

The heating device 100 shown in FIG. 1 has a heating plate 110, a plurality of heaters 120, a fixed plate 130, and a support plate 150.

The heating plate 110 is, for example, a metal plate-shaped member, and has an upper surface 110a that can come into contact with an object to be heated. That is, the upper surface 110a of the heating plate 110 serves as a heating surface for heating the object to be heated. The upper surface 110a is used, for example, for heating a mold as an example of an object to be heated. A plurality of recesses 113 (see FIG. 3) are formed on the lower surface 110b of the heating plate 110 opposite to the heating surface.

The plurality of heaters 120 are, for example, ceramic heaters having a ceramic body and a heat generating resistor located inside the ceramic body. By using the heater 120 as a ceramic heater, seizure between the metal heating plate 110 and the heater 120 can be suppressed.

The length of the heater 120, that is, the length of the ceramic body can be, for example, about 1 mm to 200 mm. Further, the outer dimensions of the ceramic body can be, for example, about 0.5 mm to 100 mm. The shape of the heater 120, that is, the shape of the ceramic body is not limited to a columnar shape, and may be, for example, an elliptical columnar shape or a prismatic shape. The material of the ceramic body is, for example, a ceramic having an insulating property. As the material of the ceramic body, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used. The heat generation resistor is a member that generates heat when an electric current flows. The heat generation resistor may include a high resistance conductor including, for example, tungsten, molybdenum and the like. The dimensions of the heat generation resistor can be, for example, a width of 0.1 mm to 5 mm, a thickness of 0.05 mm to 0.3 mm, and a total length of 1 mm to 500 mm. Further, the heat generation resistor may be a conductive ceramic containing, for example, tungsten carbide. In this case, the difference in thermal expansion between the ceramic body and the heat generation resistor can be reduced. This makes it possible to reduce the thermal stress between the ceramic body and the heat generation resistor. As a result, the durability of the heater 120 can be improved.

The plurality of heaters 120 are inserted into the plurality of recesses 113, respectively. That is, the plurality of heaters 120 are arranged so as to be perpendicular to the upper surface 110a of the heating plate 110, which is a heating surface, by being inserted into the plurality of recesses 113, respectively.

By arranging the plurality of heaters 120 perpendicularly to the heating surface of the heating plate 110 in this way, it is possible to suppress variations in the distance between the plurality of heaters 120 and the heating surface. As a result, the soaking property in the surface of the upper surface 110a of the heating plate 110, which is the heating surface, can be improved.

The plurality of recesses 113 into which the plurality of heaters 120 are inserted are formed on the lower surface 110b on the side opposite to the heating surface of the heating plate 110 at a non-uniform density. In FIG. 2, the upper surface 110a of the heating plate 110, which is a heating surface, is shown in a rectangular plate shape, and the formation positions of the plurality of recesses 113 are shown. That is, the recess 113 is sparsely formed in the central portion of the lower surface 110b, and the recess 113 is densely formed in the peripheral edge portion of the lower surface 110b. In other words, the plurality of recesses 113 are formed so that the closer to the center of the lower surface 110b, the lower the density of the recess 113, and the closer to the peripheral edge, the higher the density of the recess 113.

In this way, by adjusting the density of the plurality of recesses 113 on the lower surface 110b on the side opposite to the heating surface of the heating plate 110, the density of the plurality of heaters 120 inserted into the plurality of recesses 113 can be adjusted. can. As a result, the soaking property in the surface of the upper surface 110a of the heating plate 110, which is the heating surface, can be further improved. That is, the peripheral portions of the upper surface 110a and the lower surface 110b of the heating plate 110 are more likely to be deprived of heat by the atmosphere around the heating plate 110 than the central portion. Therefore, the temperature of the peripheral portions of the upper surface 110a and the lower surface 110b of the heating plate 110 may be lower than that of the central portion. In this case, by increasing the density of the recess 113 in the peripheral portion of the lower surface 110b, the density of the heater 120 can also be increased, so that the amount of heat generated in the peripheral portion of the upper surface 110a can be relatively increased. As a result, the amount of heat generated by the surrounding atmosphere is supplemented, so that the heat soaking property can be further improved.

In a conventional heating device in which a plurality of heaters (for example, cartridge heaters) are inserted into a plurality of holes on the side surface of the mold, if a problem such as disconnection of one cartridge heater occurs during heating, the cartridge is used. There may be a linear low temperature region along the heater. Therefore, in the conventional heating device, the temperature of the object to be heated may become non-uniform. On the other hand, the heating device 100 according to the present embodiment can narrow the region where the temperature is low even if a problem such as disconnection of one heater 120 occurs during heating. Further, the heating device 100 according to the present embodiment can make the temperature of the object to be heated uniform by controlling the output of the heater 120 close to the heater 120 in which the defect has occurred. Further, the heating device 100 according to the present embodiment can heat not only the entire area of the heating device 100 but also a local area by controlling the output of each individual heater for each arbitrary area. As a result, it is possible to further heat only an arbitrary region of the object to be heated, or to heat a plurality of objects to be heated at different temperatures, and as a result, it is possible to heat-treat a plurality of products at the same time.

The arrangement of the recess 113 is not limited to that shown in FIG. For example, when a heat spot having a higher temperature than other regions is generated on the upper surface 110a of the heating plate 110, which is a heating surface, a plurality of recesses 113 have a lower density in the region corresponding to the heat spot on the lower surface 110b. The recess 113 may be formed.

The fixing plate 130 is, for example, a metal plate-shaped member. A plurality of heaters 120 are fixed to the fixing plate 130.

The support plate 150 is fixed to the fixing plate 130 by a plurality of columnar members 151 in a state of being separated from the fixing plate 130. By locating the support plate 150 away from the fixed plate 130, it is possible to secure a space between the support plate 150 and the fixed plate 130 for arranging the

power supply terminals

122 and 123 described later in the plurality of heaters 120. It becomes. The support plate 150 and the plurality of columnar members 151 may be omitted if necessary.

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. In addition, in FIGS. 3 and 4, the support plate 150 and the plurality of columnar members 151 are not shown.

As shown in FIGS. 3 and 4, the heating device 100 is configured such that a plurality of heaters 120 are fixed to the fixed plate 130 and inserted into a plurality of recesses 113 of the heating plate 110, respectively.

The heating plate 110 has a first plate member 111 and a second plate member 112.

The first plate member 111 is a plate-shaped member having an upper surface 110a of the heating plate 110 which is a heating surface. The first plate member 111 is joined to the second plate member 112 by a joining member 114 such as a bolt. That is, the lower surface 111a on the side opposite to the upper surface 110a of the first plate member 111 is a joining surface to be joined to the second plate member 112.

The second plate member 112 is a plate-shaped member having an upper surface 112a to be joined to the joint surface of the first plate member 111 and a lower surface 110b located on the opposite side of the upper surface 112a. A plurality of through holes 112b are formed in the lower surface 110b, and the lower surface 111a of the first plate member 111 is exposed from each of the plurality of through holes 112b.

Each of the plurality of recesses 113 is formed by each of the plurality of through holes 112b and the lower surface 111a of the first plate member 111 exposed from each of the plurality of through holes 112b. That is, the inner wall surface of each through hole 112b forms the inner surface of each recess 113, and the lower surface 111a of the first plate member 111 forms the bottom surface of each recess 113. Then, the tips 120a of the plurality of heaters 120 come into contact with the lower surface 111a of the first plate member 111 in a state where the plurality of heaters 120 are inserted into the plurality of recesses 113, respectively. By bringing the tips 120a of the plurality of heaters 120 into contact with the lower surface 111a in this way, the positions of the tips 120a can be aligned with the lower surface 111a. Therefore, the distance between the plurality of heaters 120 and the heating surface can be made uniform to the distance corresponding to the thickness of the first plate member 111, and as a result, the surface of the upper surface 110a of the heating plate 110 which is the heating surface. It is possible to improve the soaking property inside.

Regarding the contact between the tip 120a of the heater 120 and the lower surface 111a of the first plate member 111, for example, when the tip 120a of the heater 120 has a hemispherically rounded shape, only the further tip of the hemisphere is the first plate. It may be in contact with the lower surface 111a of the member 111. Further, for example, when the heater 120 has a columnar shape and the heater 120 has an end face at the tip 120a, the end face of the tip 120a of the heater 120 and the lower surface 111a of the first plate member 111 come into surface contact with each other. May be. In this case, the rate of temperature rise can be increased. Further, the side portion (edge portion) of the end surface may be in contact with the lower surface 111a of the first plate member 111. In this case, the stress can be reduced while increasing the rate of temperature rise. Further, the tip 120a of the heater 120 and the lower surface 111a of the first plate member 111 are separated from each other when not in use in an environment of room temperature, so that they come into contact with each other due to thermal expansion of the heater 120 during use (during heating). It may be located in.

The fixing plate 130 has a plurality of fixing holes 130a at positions corresponding to the plurality of recesses 113. A plurality of heaters 120 are inserted and fixed in the plurality of fixing holes 130a. Specifically, a female screw is formed in a part of the inner wall of each fixing hole 130a. On the other hand, a cylindrical mounting member 121 is attached to the outer peripheral surface of each heater 120, and a male screw 121a is formed on a part of the outer peripheral surface of the mounting member 121. When each heater 120 is inserted into each fixing hole 130a, the male screw 121a is fitted into the female screw of each fixing hole 130a, so that the plurality of heaters 120 are fixed to the fixing plate 130.

The fixed plate 130 is arranged apart from the heating plate 110. As shown in FIG. 4, the fixing plate 130 has a heating plate 110 (second plate member 112) formed by a connecting member 131 such as a bolt in a state where a gap is formed between the fixing plate 130 and the heating plate 110. Is linked to. By separating the fixed plate 130 from the heating plate 110 in this way, it is possible to suppress the temperature rise of the fixed portion (for example, the portion to which the mounting member 121 is attached) of the plurality of heaters 120 with respect to the fixed plate 130. On the other hand, since the heat taken from the heating plate 110 by the fixed plate 130 is reduced, the temperature rise of the heating plate 110 can be promoted.

Further, a spacer member 140 is arranged between the heating plate 110 and the fixed plate 130. The spacer member 140 has a cylindrical shape, and the connecting member 131 is inserted therethrough. By providing the spacer member 140 between the heating plate 110 and the fixing plate 130, the possibility of collision between the fixing plate 130 and the heating plate 110 can be reduced.

The material of the spacer member 140 is preferably, for example, a ceramic having heat resistance. As the material of the spacer member 140, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used. As a result, the thermal expansion and contraction of the spacer member 140 can be reduced, so that the consumption of the spacer member 140 can be reduced.

The plurality of heaters 120 have a proximal end 120b at a position away from the upper surface 110a of the heating plate 110, which is a heating surface, rather than the lower surface of the fixed plate 130 opposite to the heating plate 110. The base end 120b is provided with

power supply terminals

122 and 123 for supplying electric power to a plurality of heaters 120. In other words, the base ends 120b of the plurality of heaters 120 project in a direction away from the upper surface 110a of the heating plate 110, which is the heating surface, from the lower surface of the fixed plate 130, and the

feeding terminals

122 and 123 are provided at the base ends 120b. ing. By providing the

feeding terminals

122 and 123 at the base end 120b protruding in the direction away from the upper surface 110a of the heating plate 110 which is the heating surface, the

feeding terminals

122 and 123 can be kept away from the heating surface. As a result, the

feeding terminals

122 and 123 can be protected from the heat of the heating surface.

<Modified example of the first embodiment>
Next, various modifications of the first embodiment will be described with reference to FIG. In the following description, the same reference numerals will be given to the configurations common to the above-described first embodiment, and detailed description thereof will be omitted.

FIG. 5 is a cross-sectional view of the heating device 100 according to the first modification of the first embodiment. The heating device 100 shown in FIG. 5 is different from the heating device 100 shown in FIGS. 1 to 4 mainly in the structure of the heating plate and the insertion mode of the plurality of heaters. Specifically, as shown in FIG. 5, the heating plate 110 has a first plate member 111, a second plate member 112, and a heat insulating member 115.

The first plate member 111 is a plate-shaped member having an upper surface 110a of the heating plate 110 which is a heating surface. The first plate member 111 is attached to the second plate member 112 by a joining member 114 such as a bolt in a state where the heat insulating member 115 is arranged between the first plate member 111 and the second plate member 112. It is joined. That is, the lower surface 111a on the side opposite to the upper surface 110a of the first plate member 111 is a joining surface to be joined to the second plate member 112. A plurality of recesses 111b are formed on the lower surface 111a on the side opposite to the heating surface of the first plate member 111.

The second plate member 112 is a plate-shaped member having an upper surface 112a to be joined to the joint surface of the first plate member 111 and a lower surface 110b located on the opposite side of the upper surface 112a. A plurality of through holes 112b are formed at positions corresponding to the plurality of recesses 111b of the second plate member 112.

The heat insulating member 115 is interposed between the first plate member 111 and the second plate member 112. The heat insulating member 115 is, for example, a sheet-like member made of fibers having heat insulating properties, and has a function of limiting heat transfer from the first plate member 111 side to the second plate member 112 side. A plurality of through holes 115a are formed at positions corresponding to the plurality of recesses 111b of the heat insulating member 115.

The material of the heat insulating member 115 is preferably, for example, ceramics having heat insulating properties. As the material of the heat insulating member 115, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used.

Each of the plurality of recesses 113 is formed by each of the plurality of through holes 112b, each of the plurality of through holes 115a, and the plurality of recesses 111b. That is, the inner surface of each through hole 112b, the inner surface of each through hole 115a, and the inner side surface of each recess 111b form the inner surface of each recess 113, and the bottom surface of each recess 111b forms the bottom surface of each recess 113. There is. The tips 120a of the plurality of heaters 120 are located in the plurality of recesses 111b with the plurality of heaters 120 inserted into the plurality of recesses 113, respectively.

By locating the tips 120a of the plurality of heaters 120 in the plurality of recesses 111b, for example, when each tip 120a of the plurality of heaters 120 has a maximum heating point at which the temperature becomes maximum, the maximum heating point is set on the heating surface. It can be brought close to the upper surface 110a of a certain heating plate 110. As a result, according to the heating device 100 according to the first modification, the upper surface 110a of the heating plate 110, which is a heating surface, can be efficiently heated. Further, since the tips 120a of the plurality of heaters 120 are located in the plurality of recesses 111b, the maximum heat generation point can be kept away from the base ends 120b of the plurality of heaters 120. As a result, according to the heating device 100 according to the first modification, it becomes difficult for heat from the maximum heat generation point to be transferred to the

feeding terminals

122 and 123 provided at the base ends 120b of the plurality of heaters 120, so that the

feeding terminals

122 and 123 are difficult to transfer. Deterioration can be suppressed.

Note that each tip 120a of the plurality of heaters 120 may or may not be in contact with the bottom surface of each recess 111b.

Further, the fixed plate 130 is arranged apart from the heating plate 110 by being connected to the heating plate 110 via a columnar connecting metal fitting 160 having a predetermined length. The length of the connecting metal fitting 160 can be longer than, for example, the thickness of the spacer member 140 shown in FIG.

FIG. 6 is a side view of the heating device 100 according to the second modification of the first embodiment. FIG. 7 is a cross-sectional view of the heating device 100 according to the second modification of the first embodiment. The heating device 100 shown in FIGS. 6 and 7 basically has the same structure as the heating device 100 shown in FIGS. 1 to 4. However, in the heating device 100 shown in FIGS. 6 and 7, the heating plate 110 is not divided into two members, the first plate member 111 and the second plate member 112, and the heating shown in FIGS. 1 to 4 is performed. It is different from the device 100. Specifically, as shown in FIGS. 6 and 7, in the heating plate 110, the portions corresponding to the first plate member 111 and the second plate member 112 are integrally formed of a metal plate-shaped member. Has been done. As a result, according to the heating device 100 according to the second modification, the manufacturing process of the heating device 100 can be simplified.

As described above, the heating device (for example, the heating device 100) according to the first embodiment has a heating plate (for example, a heating plate 110) and a plurality of heaters (for example, a heater 120). The heating plate has a heating surface (for example, the upper surface 110a), and has a plurality of recesses (for example, the recess 113) on the back surface (for example, the lower surface 110b) opposite to the heating surface. The plurality of heaters are located in each of the plurality of recesses. This makes it possible to improve the in-plane heat equalizing property of the heated surface.

Further, the heating plate according to the first embodiment is a metal member. The plurality of heaters are ceramic heaters having a ceramic body and a heat generation resistor located inside the ceramic body. As a result, seizure between the metal heating plate and the heater can be suppressed.

Further, the heating plate according to the first embodiment has a first plate member (for example, the first plate member 111) and a second plate member (for example, the second plate member 112). The first plate member has a heated surface and a joint surface (eg, lower surface 111a) located opposite the heated surface. The second plate member has a surface to be joined to be joined to the surface to be joined, a back surface located opposite to the surface to be joined, and a plurality of through holes (for example, through holes 112b) penetrating from the back surface to the surface to be joined. Have. Each of the plurality of recesses consists of each of the plurality of through holes and a joint surface. The tips of the plurality of heaters (for example, the tips 120a) are in contact with each other. As a result, the distance between the plurality of heaters and the heating surface can be made uniform to the distance corresponding to the thickness of the first plate member, and as a result, the heat equalization property in the surface of the heating surface can be improved. can.

Further, the heating device according to the first embodiment further has a fixed plate (for example, a fixed plate 130). The fixing plate 130 fixes a plurality of heaters at a position away from the heating plate. As a result, it is possible to suppress the temperature rise of the fixed portions of the plurality of heaters with respect to the fixed plate and promote the temperature rise of the heating plate.

Further, the heating device according to the first embodiment further has a spacer member (for example, a spacer member 140) between the heating plate and the fixing plate. This makes it possible to reduce the possibility of collision between the fixed plate and the heating plate.

Further, the spacer member according to the first embodiment is made of ceramics. This makes it possible to reduce the wear of the spacer member.

Further, the fixing plate according to the first embodiment has a plurality of fixing holes (for example, fixing holes 130a) through which a plurality of heaters are inserted and fixed at positions corresponding to the plurality of recesses. The plurality of heaters have a proximal end (eg, proximal end 120b) at a position away from the heating surface than the back surface of the fixed plate opposite the heating plate. A feeding terminal (for example, feeding terminals 122 and 123) for supplying electric power to a plurality of heaters is provided at the base end. This makes it possible to protect the feeding terminal from the heat of the heating surface.

Further, the heating device according to the first embodiment further has a support plate (for example, a support plate 150). The support plate is fixed to the fixing plate by a plurality of columnar members (for example, columnar member 151) in a state separated from the fixing plate. This makes it possible to secure a space between the support plate and the fixed plate for arranging the feeding terminals in the plurality of heaters.

Further, the plurality of recesses according to the first embodiment are partially dense in the surface direction and the other part on the back surface is rough. This makes it possible to further improve the in-plane heat equalizing property of the heated surface.

Further, the heating device according to the first embodiment is a mold heating device. This makes it possible to improve the in-plane heat soaking property of the heating surface used for heating the mold.

Further, the heating plate according to the first embodiment has a first plate member, a second plate member, and a heat insulating member (for example, a heat insulating member 115). The first plate member has a heating surface, a joint surface (for example, a lower surface 111a) located opposite to the heating surface, and a plurality of first recesses (111b) located on the joint surface. The second plate member is located corresponding to the surface to be joined to the joint surface, the back surface located opposite to the surface to be joined, and the plurality of first recesses, and penetrates from the back surface to the surface to be joined. It has a plurality of first through holes (eg, through holes 112b). The heat insulating member has a plurality of second through holes (for example, through holes 115a) located between the first plate member and the second plate member and corresponding to the plurality of first recesses. .. Each of the plurality of recesses comprises each of the plurality of first through holes, each of the plurality of second through holes, and each of the plurality of first through holes. The tips of the plurality of heaters are in contact with each of the plurality of first recesses. As a result, the heating surface can be efficiently heated, and deterioration of the feeding terminals provided at the base ends of the plurality of heaters can be suppressed.

<Second Embodiment>
FIG. 8 is a side view of the heating device 100A according to the second embodiment. FIG. 9 is a top view of the heating device 100A according to the second embodiment. FIG. 10 is a cross-sectional view taken along the line XX of FIG. In the following description, the same reference numerals will be given to the configurations common to the modification 1 of the first embodiment described above, and detailed description thereof will be omitted.

The heating device 100A shown in FIGS. 8 to 10 is different from the heating device 100 according to the first modification of the first embodiment shown in FIG. 5, mainly in terms of the structure of the connecting member and the positional relationship between the connecting member and the joining member. It's different. The heating plate 110 of the heating device 100A shown in FIGS. 8 to 10 has a first plate member 111, a second plate member 112, and a heat insulating member 115, similarly to the heating plate 110 of the heating device 100 shown in FIG. ..

The second plate member 112 is a plate-shaped member having an upper surface 112a to be joined to the joint surface of the first plate member 111 and a lower surface 110b located on the opposite side of the upper surface 112a. The second plate member 112 is formed with a screw hole 112c that penetrates the upper surface 112a and the lower surface 110b. For example, a plurality of (here, four) screw holes 112c are formed in the second plate member 112. Female threads are formed on the inner wall surface of each screw hole 112c.

In the fixed plate 130A, a plurality of heaters 120 are fixed and arranged apart from the second plate member 112. As shown in FIGS. 9 and 10, the fixing plate 130A is connected to the second plate member 112 by a connecting member 131A such as a bolt in a state where a gap is formed between the fixing plate 130A and the heating plate 110. Has been done. For example, the fixed plate 130A is connected to the second plate member 112 by a plurality of (here, four) connecting members 131A.

The connecting member 131A has a tip 131Aa on which a male screw that can be fitted into the female screw of the screw hole 112c of the second plate member 112 is formed. The tip 131Aa of the connecting member 131A fits into the screw hole 112c of the second plate member 112 and extends in the direction of the first plate member 111 with a length that does not penetrate the heat insulating member 115. In the present embodiment, the tip 131Aa of the connecting member 131A extends from the lower surface 110b of the second plate member 112 to the position reaching the upper surface 112a in the screw hole 112c, and comes into contact with the surface of the heat insulating member 115 exposed from the screw hole 112c. is doing.

In this way, the tip 131Aa of the connecting member 131A extends in the direction of the first plate member 111 so as not to penetrate the heat insulating member 115, thereby avoiding contact between the connecting member 131A and the first plate member 111. can. As a result, heat conduction from the first plate member 111 having the upper surface 110a, which is the heating surface, to the connecting member 131A can be suppressed.

Further, by bringing the tip 131Aa of the connecting member 131A into contact with the surface of the heat insulating member 115, the positions of the tips 131Aa of the plurality of connecting members 131A can be aligned with the surface of the heat insulating member 115. Therefore, the length of the heat transfer path from the first plate member 111 to the tip 131Aa of the plurality of connecting members 131A can be made uniform, and as a result, the heat soaking property of the first plate member 111 can be improved. Can be done.

Further, the connecting member 131A has a spacer member 140A on the outer periphery of a portion located between the fixed plate 130A and the second plate member 112. The spacer member 140A has a cylindrical shape that surrounds the outer periphery of the portion located between the fixing plate 130A of the connecting member 131A and the second plate member 112, and is in contact with the fixing plate 130A and the second plate member 112. .. A gap may or may not be provided between the inner peripheral surface of the spacer member 140A and the outer peripheral surface of the connecting member 131A. By surrounding the outer periphery of the connecting member 131A with the tubular spacer member 140A, it is possible to suppress the heat of the connecting member 131A from being released to the space around the connecting member 131A.

As the material of the spacer member 140A, for example, a metal such as stainless steel can be used. As a result, the durability of the spacer member 140A can be improved, and the distance between the fixing plate 130A and the second plate member 112 can be kept constant.

As shown in FIGS. 9 and 10, the second plate member 112 is, for example, joined with bolts or the like in a state where the heat insulating member 115 is arranged between the first plate member 111 and the second plate member 112. It is joined to the first plate member 111 by the member 114A. For example, the second plate member 112 is joined to the first plate member 111 by a plurality of (here, four) joining members 114A.

By the way, the first plate member 111 having the upper surface 110a which is a heating surface and the second plate member 112 are thermally connected via the joining member 114A. In order to further suppress heat conduction from the first plate member 111 to the connecting member 131A, the positional relationship between the connecting member 131A and the joining member 114A makes the heat transfer path from the joining member 114A to the connecting member 131A as long as possible. It is important to have a relationship.

Therefore, in the heating device 100A according to the present embodiment, as shown in FIG. 9, the connecting member 131A is located at a position where it does not overlap with the joining member 114A in a plan view. As a result, the heat transfer path from the joining member 114A to the connecting member 131A becomes long, and as a result, heat conduction from the first plate member 111 to the connecting member 131A via the joining member 114A can be further suppressed.

Further, as shown in FIGS. 9 and 10, the connecting member 131A is located at a position where one of the plurality of recesses 113 is sandwiched between the connecting member 131A and the joining member 114A in a plan view and a side view. By locating the recess 113 between the connecting member 131A and the joining member 114A, the heat transfer path from the joining member 114A to the connecting member 131A becomes a path that bypasses the recess 113. As a result, heat conduction from the first plate member 111 to the connecting member 131A via the joining member 114A can be further suppressed. The number of the recesses 113 sandwiched between the connecting member 131A and the joining member 114A in the plan view and the side view is not limited to one, and may be two or more.

Further, the connecting member 131A is located closer to the center of the second plate member 112 than the joining member 114A in the plan view and the side view. As a result, since the position near the center of the heating plate 110 is supported by the connecting member 131A, it is possible to suppress the bending of the center of the heating plate 110 due to its own weight. Further, since the joining member 114A is located at a position farther from the center of the second plate member 112 than the connecting member 131A, heat conduction from the center of the heating plate 110 (first plate member 111) to the joining member 114A. Can be suppressed.

By the way, the portion of the first plate member 111 located in the vicinity of the joining member 114A is more likely to lose heat to the joining member 114A than the other portions. Therefore, the temperature of the portion of the first plate member 111 located in the vicinity of the joining member 114A may be lower than that of the other portions. If the temperature becomes low in the portion of the first plate member 111 located in the vicinity of the joining member 114A, the heat equalizing property of the first plate member 111 may be impaired.

Therefore, in the heating device 100A according to the present embodiment, as shown in FIG. 9, the joining member 114A is inside the recess 113 closest to the peripheral edge of the lower surface 110b (see FIG. 10) among the plurality of recesses 113 in a plan view. positioned. As a result, since the periphery of the joining member 114A is surrounded by the plurality of recesses 113, the portion of the first plate member 111 located in the vicinity of the joining member 114A is formed by the plurality of heaters 120 inserted into the plurality of recesses 113, respectively. Be heated. As a result, it is possible to suppress the temperature drop of the portion of the first plate member 111 located in the vicinity of the joining member 114A, and it is possible to maintain the soaking property of the first plate member 111.

Further, as shown in FIG. 10, the joining member 114A penetrates the heat insulating member 115 and has a spacer member 170 on the outer periphery of the penetrating portion. The spacer member 170 has a cylindrical shape surrounding a portion of the joining member 114A that penetrates the heat insulating member 115, and is in contact with the first plate member 111 and the second plate member 112. A gap may or may not be provided between the inner peripheral surface of the spacer member 170 and the outer peripheral surface of the joining member 114A. By surrounding the outer periphery of the joining member 114A with the tubular spacer member 170, it is possible to suppress the heat transfer of the joining member 114A to the heat insulating member 115.

The spacer member 170 is preferably, for example, a ceramic having a relatively high heat insulating property. As the material of the spacer member 170, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used. As a result, heat transfer from the joining member 114A to the heat insulating member 115 can be further suppressed.

<Modified example of the second embodiment>
Next, various modifications of the second embodiment will be described with reference to FIGS. 11 to 13. In the following description, the same reference numerals are given to the configurations common to the above-mentioned second embodiment, and detailed description thereof will be omitted.

FIG. 11 is a cross-sectional view of the heating device 100A according to the first modification of the second embodiment. The heating device 100A shown in FIG. 11 mainly has a structure of the tip 131Aa of the connecting member 131A different from that of the heating device 100A shown in FIGS. 8 to 10.

The tip 131Aa of the connecting member 131A shown in FIG. 11 extends from the lower surface 110b of the second plate member 112 to a position where it does not reach the upper surface 112a in the screw hole 112c. The tip 131Aa of the connecting member 131A forms a gap 112d between the end surface of the tip 131Aa and the surface of the heat insulating member 115 exposed from the screw hole 112c.

A gas such as air exists in the gap 112d. The air in the gap 112d has a lower thermal conductivity than the heat insulating member 115. Therefore, by forming a gap 112d between the end surface of the tip 131Aa of the connecting member 131A and the surface of the heat insulating member 115, heat conduction from the heat insulating member 115 to the connecting member 131A can be suppressed. As a result, heat conduction from the first plate member 111 having the upper surface 110a, which is the heating surface, to the connecting member 131A via the heat insulating member 115 can be suppressed.

FIG. 12 is a cross-sectional view of the heating device 100A according to the second modification of the second embodiment. The heating device 100A shown in FIG. 12 is different from the heating device 100A shown in FIGS. 8 to 10 mainly in the structure of the tip 131Aa of the connecting member 131A and the structure of the heat insulating member 115.

The tip 131Aa of the connecting member 131A shown in FIG. 12 extends from the lower surface 110b of the second plate member 112 to a position where it does not reach the upper surface 112a in the screw hole 112c. The tip 131Aa of the connecting member 131A is in contact with a part of the heat insulating member 115 filled in the screw hole 112c.

In this way, by bringing a part of the heat insulating member 115 filled in the screw hole 112c into contact with the tip 131Aa of the connecting member 131A, the thickness of the heat insulating member 115 is locally adjusted at the position corresponding to the tip 131Aa of the connecting member 131A. Can be increased to. As a result, heat conduction from the first plate member 111 having the upper surface 110a, which is the heating surface, to the connecting member 131A via the heat insulating member 115 can be suppressed.

FIG. 13 is a cross-sectional view of the heating device 100A according to the third modification of the second embodiment. The heating device 100A shown in FIG. 13 mainly has a structure of the tip 131Aa of the connecting member 131A different from that of the heating device 100A shown in FIGS. 8 to 10.

The tip 131Aa of the connecting member 131A shown in FIG. 13 protrudes from the screw hole 112c toward the heat insulating member 115, extends toward the first plate member 111, and is embedded inside the heat insulating member 115.

In this way, by embedding the tip 131Aa of the connecting member 131A inside the heat insulating member 115, it is possible to suppress the misalignment of the heat insulating member 115.

As described above, the heating device (for example, the heating device 100A) according to the second embodiment further includes a fixed plate (for example, the fixed plate 130A) and a connecting member (for example, the connecting member 131A). The fixing plate fixes a plurality of heaters (for example, heater 120) at a position away from the second plate member (for example, the second plate member 112). The connecting member connects the fixed plate and the second plate member. The connecting member has a length at which the tip is engaged with the screw hole (for example, the screw hole 112c) provided in the second plate member and does not penetrate the heat insulating member (for example, the heat insulating member 115) in the direction of the first plate member. It extends at. This makes it possible to suppress heat conduction from the first plate member having the heating surface (for example, the first plate member 111) to the connecting member.

Further, the tip of the connecting member according to the second embodiment extends from the back surface (for example, the lower surface 110b) to the position reaching the bonded surface (for example, the upper surface 112a) in the screw hole, and the surface of the heat insulating member exposed from the screw hole. Contact. As a result, the length of the heat transfer path from the first plate member to the tips of the plurality of connecting members can be made uniform, and as a result, the heat soaking property of the first plate member can be improved.

Further, the connecting member according to the second embodiment may extend from the back surface to a position where it does not reach the surface to be joined in the screw hole, and may be located away from the surface of the heat insulating member exposed from the screw hole. This makes it possible to suppress heat conduction from the first plate member having a heating surface to the connecting member via the heat insulating member.

Further, the tip of the connecting member according to the second embodiment may extend from the back surface to a position where it does not reach the surface to be joined in the screw hole and may come into contact with a part of the heat insulating member filled in the screw hole. This makes it possible to suppress heat conduction from the first plate member having a heating surface to the connecting member via the heat insulating member.

Further, the tip of the connecting member according to the second embodiment may protrude from the screw hole toward the heat insulating member and extend toward the first plate member, and may be embedded inside the heat insulating member. This makes it possible to suppress the misalignment of the heat insulating member.

Further, the heating device according to the second embodiment further has a joining member (for example, joining member 114A) for joining the second plate member to the first plate member. The joining member is located so as not to overlap the connecting member in a plan view. As a result, heat conduction from the first plate member to the connecting member via the joining member can be further suppressed.

Further, the heating device according to the second embodiment has at least one recess among a plurality of recesses between the connecting member and the joining member. As a result, heat conduction from the first plate member to the connecting member via the joining member can be further suppressed.

Further, the connecting member according to the second embodiment is located closer to the center of the second plate member than the joining member. As a result, it is possible to suppress the bending of the center of the heating plate due to its own weight and to suppress the heat conduction from the center of the heating plate to the joining member.

Further, the joining member according to the second embodiment is located inside the recess closest to the peripheral edge of the back surface among the plurality of recesses. As a result, the portion of the first plate member located near the joint member is heated by the plurality of heaters inserted into the plurality of recesses, so that the temperature drop of the portion can be suppressed, and the first It is possible to maintain the soaking property of the plate member.

Further, the joining member according to the second embodiment has a first spacer member (for example, a spacer member 170). The first spacer member is an annular body, is surrounded by a heat insulating member, and is in contact with the first plate member and the second plate member. As a result, it is possible to prevent the heat of the joining member from being transferred to the heat insulating member.

Further, the first spacer member according to the second embodiment is formed of ceramic. This makes it possible to further suppress heat transfer from the joining member to the heat insulating member.

Further, the connecting member according to the second embodiment has a second spacer member (for example, a spacer member 140A). The second spacer member is a cylindrical body and is in contact with the fixing plate and the second plate member. As a result, it is possible to suppress the heat of the connecting member from being released to the space around the connecting member.

Further, the second spacer member according to the second embodiment is formed of metal. As a result, the durability of the spacer member can be improved, and the distance between the fixing plate and the second plate member can be kept constant.

<Third Embodiment>
FIG. 14 is a cross-sectional view of the heating device 100B according to the third embodiment. In the following description, the same reference numerals are given to the configurations common to the above-mentioned second embodiment, and detailed description thereof will be omitted.

The structure of the first plate member of the heating device 100B shown in FIG. 14 is different from that of the heating device 100A shown in FIGS. 8 to 10. Specifically, in the heating device 100B shown in FIG. 14, the first plate member 111 has a groove portion 111c on the lower surface 111a. The groove 111c extends from the peripheral edge of the lower surface 111a toward the center, and the opening at the top is closed by the heat insulating member 115.

As described above, by providing the groove portion 111c on the lower surface 111a of the first plate member 111, the thermal expansion and contraction of the first plate member 111 due to the heat cycle can be absorbed by the groove portion 111c.

The first plate member 111 may be provided with a horizontal hole or a vertical hole instead of the groove portion 111c.

<Fourth Embodiment>
FIG. 15 is a cross-sectional view of the heating device 100C according to the fourth embodiment. In the following description, the same reference numerals will be given to the configurations common to the above-mentioned third embodiment, and detailed description thereof will be omitted.

The heating device 100C shown in FIG. 15 is different from the heating device 100B shown in FIG. 14 in that it has a temperature measuring element. Specifically, in the heating device 100C shown in FIG. 15, the first plate member 111 has a temperature measuring element 180 inserted through the groove portion 111c. As the temperature measuring element 180, for example, a thermocouple can be used.

In this way, the temperature of the first plate member 111 can be measured by inserting the temperature measuring element 180 into the groove 111c of the first plate member 111.

<Fifth Embodiment>
FIG. 16 is a side view of the heating device 100D according to the fifth embodiment. FIG. 17 is a cross-sectional view of the heating device 100D according to the fifth embodiment. In the following description, the same reference numerals will be given to the configurations common to the modification 2 of the first embodiment described above, and detailed description thereof will be omitted.

The heating device 100D shown in FIGS. 16 and 17 is different from the heating device 100 according to the second modification of the first embodiment shown in FIGS. 6 and 7, mainly in the structure of the fixed plate and the like. Specifically, the fixed plate 130B has a third plate member 132, a fourth plate member 133, and a heat insulating member 135.

The third plate member 132 is a metal plate-shaped member having a facing surface 132a facing the heating plate 110. The third plate member 132 has a fourth plate with a joining member (not shown) such as a bolt in a state where the heat insulating member 135 is arranged between the third plate member 132 and the fourth plate member 133. It is joined to the member 133.

The fourth plate member 133 is a metal plate-shaped member joined to the back surface of the third plate member 132 opposite to the facing surface 132a. A plurality of heaters 120 are fixed to the fourth plate member 133. That is, the fourth plate member 133 has a plurality of fixing holes 130a at positions corresponding to the plurality of recesses 113, and the plurality of heaters 120 are inserted and fixed in the plurality of fixing holes 130a, respectively. Specifically, a female screw is formed in a part of the inner wall of each fixing hole 130a. On the other hand, a cylindrical mounting member 121 is attached to the outer peripheral surface of each heater 120, and a male screw 121a is formed on a part of the outer peripheral surface of the mounting member 121. When the male screw 121a is inserted into each fixing hole 130a, the plurality of heaters 120 are fixed to the fourth plate member 133 by being fitted into the female screw of each fixing hole 130a. .. The third plate member 132 and the heat insulating member 135 are each formed with through holes through which the heater 120 can be inserted, corresponding to the fixing holes 130a.

The heat insulating member 135 is interposed between the third plate member 132 and the fourth plate member 133. The heat insulating member 135 is, for example, a sheet-like member made of fibers having heat insulating properties, and has a function of limiting heat transfer from the third plate member 132 side to the fourth plate member 133 side.

The material of the heat insulating member 135 is preferably, for example, ceramics having heat insulating properties. As the material of the heat insulating member 135, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used.

As described above, since the fixed plate 130B has the heat insulating member 135, it is possible to suppress the temperature rise of the fixed portion (for example, the portion to which the mounting member 121 is attached) of the plurality of heaters 120 with respect to the fixed plate 130B.

<Sixth Embodiment>
FIG. 18 is a side view of the heating device 100E according to the sixth embodiment. FIG. 19 is a cross-sectional view of the heating device 100E according to the sixth embodiment. In the following description, the same reference numerals will be given to the configurations common to the modification 2 of the first embodiment described above, and detailed description thereof will be omitted.

The heating device 100E shown in FIGS. 18 and 19 is different from the heating device 100 according to the second modification of the first embodiment shown in FIGS. 6 and 7 in that it mainly has a heat insulating plate. Specifically, the heating device 100E shown in FIGS. 18 and 19 has a heat insulating plate 190 located between the heating plate 110 and the fixed plate 130.

The heat insulating plate 190 has a fifth plate member 191 and a sixth plate member 192 and a heat insulating member 195. The fifth plate member 191 and the sixth plate member 192 and the heat insulating member 195 are each formed with a plurality of through holes through which a plurality of heaters 120 fixed to the fixed plate 130 can be inserted.

The fifth plate member 191 is a metal plate-shaped member having a facing surface 191a facing the heating plate 110. The fifth plate member 191 is a sixth plate with a joining member (not shown) such as a bolt in a state where the heat insulating member 195 is arranged between the fifth plate member 191 and the sixth plate member 192. It is joined to the member 192. Further, the fifth plate member 191 is arranged apart from the heating plate 110 by being connected to the heating plate 110 via a columnar connecting metal fitting 196 having a predetermined length. The length of the connecting metal fitting 196 can be longer than, for example, the thickness of the spacer member 140 shown in FIGS. 6 and 7.

The sixth plate member 192 is a metal plate-shaped member joined to the back surface of the fifth plate member 191 opposite to the facing surface 191a. The sixth plate member 192 is arranged apart from the fixed plate 130 by being connected to the fixed plate 130 via a columnar connecting metal fitting 197 having a predetermined length. The length of the connecting metal fitting 197 can be longer than, for example, the thickness of the spacer member 140 shown in FIGS. 6 and 7.

The heat insulating member 195 is interposed between the fifth plate member 191 and the sixth plate member 192. The heat insulating member 195 is, for example, a sheet-like member made of fibers having heat insulating properties, and has a function of limiting heat transfer from the fifth plate member 191 side to the sixth plate member 192 side.

The material of the heat insulating member 195 is preferably, for example, ceramics having heat insulating properties. As the material of the heat insulating member 195, for example, oxide ceramics, nitride ceramics, carbide ceramics and the like can be used.

In this way, by locating the heat insulating plate 190 between the heating plate 110 and the fixed plate 130, it is possible to suppress the temperature rise of the fixed plate 130.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments described and described above. Thus, various modifications can be made without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents.

100, 100A-100E Heating device 110 Heating plate 110a Upper surface 110b Lower surface 111 First plate member 111a Lower surface 111b Recessed 111c Groove 112 Second plate member 112a Upper surface 112b Through hole 112c Threaded hole 112d Gap 113 Recessed 114, 114A Joining member 115 Insulation member 115a Through hole 120 Heater 120a Tip 120b Base end 121 Mounting member 121a

Male screw

122, 123

Power supply terminal

130, 130A, 130B Fixing plate

130a Fixing hole

131, 131A Connecting member 131Aa Tip 132 Third plate member 132a Facing surface 133 Fourth plate member 135

Insulation member

140, 140A Spacer member 170 Spacer member 180 Temperature measuring element 190 Insulation plate 191 Fifth plate member 191a Opposing surface 192 Sixth plate member 195 Insulation member

Claims

A heating plate having a heating surface and having a plurality of recesses on the back surface opposite to the heating surface.
A heating device having a plurality of heaters located in each of the plurality of recesses.
The heating plate is a metal member and is a member.
The heating device according to claim 1, wherein the plurality of heaters are a ceramic body and a ceramic heater having a heat generation resistor located inside the ceramic body.
The heating plate is
A first plate member having a heated surface and a joint surface located opposite to the heated surface.
It has a surface to be joined to be joined to the surface to be joined, a back surface located opposite to the surface to be joined, and a second plate member having a plurality of through holes penetrating from the back surface to the surface to be joined. death,
Each of the plurality of recesses is composed of each of the plurality of through holes and the joint surface.
The heating device according to claim 1 or 2, wherein the tips of the plurality of heaters are in contact with the joint surface, respectively.
The heating plate is
A first plate member having a heating surface, a joining surface located opposite to the heating surface, and a plurality of first recesses located on the joining surface.
A plurality of surfaces to be joined to the joint surface, the back surface located opposite to the joint surface, and a plurality of positions corresponding to the plurality of first recesses and penetrating from the back surface to the joint surface. A second plate member having a first through hole in the
It has a heat insulating member having a plurality of second through holes located between the first plate member and the second plate member and corresponding to the plurality of first recesses.
Each of the plurality of recesses comprises each of the plurality of first through holes, each of the plurality of second through holes, and each of the plurality of first through holes.
The heating device according to claim 1 or 2, wherein the tips of the plurality of heaters are in contact with the plurality of first recesses, respectively.
The heating device according to any one of claims 1 to 4, further comprising a fixing plate for fixing the plurality of heaters at a position away from the heating plate.
The heating device according to claim 5, further comprising a spacer member between the heating plate and the fixing plate.
The heating device according to claim 6, wherein the spacer member is made of ceramics.
The fixing plate has a plurality of fixing holes in which the plurality of heaters are inserted and fixed at positions corresponding to the plurality of recesses.
The plurality of heaters have a proximal end at a position farther from the heating surface than the back surface of the fixed plate opposite to the heating plate.
The heating device according to any one of claims 5 to 7, wherein the base end is provided with a power supply terminal for supplying electric power to the plurality of heaters.
A fixed plate for fixing the plurality of heaters at a position away from the second plate member, and
Further having a connecting member for connecting the fixing plate and the second plate member.
4. The fourth aspect of the present invention, wherein the connecting member has a tip engaged with a screw hole provided in the second plate member and extends in the direction of the first plate member so as not to penetrate the heat insulating member. Heating device.
The connecting member is
The heating device according to claim 9, wherein the heating device extends from the back surface of the screw hole to a position where the surface to be joined does not reach, and is located away from the surface of the heat insulating member exposed from the screw hole.
Further having a joining member for joining the second plate member to the first plate member.
The joining member is
The heating device according to claim 9 or 10, which is located so as not to overlap with the connecting member in a plan view.
The heating device according to claim 11, further comprising at least one of the plurality of recesses between the connecting member and the joining member.
The connecting member is
The heating device according to claim 11 or 12, which is located closer to the center of the second plate member than the joining member.
The joining member is
The heating device according to any one of claims 11 to 13, which is located inside the recesses closest to the peripheral edge of the back surface among the plurality of recesses.
The joining member is
Has a first spacer member
One of claims 11 to 14, wherein the first spacer member is an annular body, is surrounded by the heat insulating member, and is in contact with the first plate member and the second plate member. The heating device according to one.
The connecting member is
Has a second spacer member
The heating device according to any one of claims 10 to 15, wherein the second spacer member is a cylindrical body and is in contact with the fixing plate and the second plate member.
The heating device according to any one of claims 1 to 16, wherein the plurality of recesses are partially dense in the surface direction and the other part of the back surface is rough.
The first plate member is
The heating device according to claim 4, further comprising a groove extending from the peripheral edge of the joint surface toward the center and being closed by the heat insulating member.
The first plate member is
The heating device according to claim 18, which has a temperature measuring element in the groove.
The heating device according to any one of claims 1 to 19, which is a mold heating device.