heating device

Abstract

To improve the uniformity of heat within the heating surface. The heating device includes a heating plate and a plurality of heaters. The heating plate has a heating surface and a plurality of recesses formed on the back surface opposite the heating surface. The heaters are inserted into the recesses, respectively.

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION The disclosed embodiments relate to a heating device. [Background technology]

[0002] Patent Document 1 discloses a heating device in which a plurality of heaters are inserted into a plurality of holes formed in the side surface of a mold, so that the heaters are arranged parallel to the heating surface of the mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-154409 Summary of the Invention

[0004] A heating device according to one aspect of the embodiment includes a heating plate and a plurality of heaters. The heating plate has a heating surface and a plurality of recesses on a back surface opposite the heating surface. The plurality of heaters are located in the plurality of recesses, respectively. [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 is a side view of the heating device according to the first embodiment. [Figure 2] FIG. 2 is a top view of the heating device according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a cross-sectional view of a heating device according to Modification 1 of the first embodiment. [Figure 6] FIG. 6 is a side view of a heating device according to a second modification of the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view of a heating device according to a second modification of the first embodiment. [Figure 8] FIG. 8 is a side view of the heating device according to the second embodiment. [Figure 9] FIG. 9 is a top view of the heating device according to the second embodiment. [Figure 10] FIG. 10 is a cross-sectional view taken along line XX in FIG. [Figure 11] FIG. 11 is a cross-sectional view of a heating device according to a first modification of the second embodiment. [Figure 12] FIG. 12 is a cross-sectional view of a heating device according to Modification 2 of the second embodiment. [Figure 13] FIG. 13 is a cross-sectional view of a heating device according to a third modification of the second embodiment. [Figure 14] FIG. 14 is a cross-sectional view of a heating device according to a third embodiment. [Figure 15] FIG. 15 is a cross-sectional view of a heating device according to a fourth embodiment. [Figure 16] FIG. 16 is a side view of the heating device according to the fifth embodiment. [Figure 17] FIG. 17 is a cross-sectional view of a heating device according to a fifth embodiment. [Figure 18] FIG. 18 is a side view of the heating device according to the sixth embodiment. [Figure 19] FIG. 19 is a cross-sectional view of a heating device according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0006] Hereinafter, embodiments of the heating device disclosed in the present application will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments shown below. It should be noted that the drawings are schematic, and the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may include parts with different dimensional relationships and ratios.

[0007] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0008] 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 facing the object to be heated is referred to as the "upper surface," and the surface facing the opposite side of the object to be heated is referred to as the "lower surface." However, the heating device 100 may be used, for example, upside down, or in any position.

[0009] The heating device 100 shown in FIG. 1 includes a heating plate 110, a plurality of heaters 120, a fixing plate 130, and a support plate 150.

[0010] The heating plate 110 is, for example, a metal plate-like 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 that heats the object to be heated. The upper surface 110a is used, for example, to heat a mold, which is an example of an object to be heated. A plurality of recesses 113 (see FIG. 3) are formed on a lower surface 110b of the heating plate 110 opposite the heating surface.

[0011] The heaters 120 are, for example, ceramic heaters each having a ceramic body and a heating resistor located inside the ceramic body. By using a ceramic heater as the heater 120, it is possible to prevent seizure between the heater 120 and the heating plate 110, which is made of metal.

[0012] The length of the heater 120, i.e., the length of the ceramic body, can be, for example, approximately 1 mm to 200 mm. The outer dimensions of the ceramic body can be, for example, approximately 0.5 mm to 100 mm. The shape of the heater 120, i.e., the shape of the ceramic body, is not limited to a cylindrical shape, but can also be, for example, an elliptical cylindrical shape or a rectangular cylindrical shape. The ceramic body is made of, for example, an insulating ceramic. Examples of materials that can be used for the ceramic body include oxide ceramics, nitride ceramics, and carbide ceramics. The heating resistor is a component that generates heat when a current flows through it. The heating resistor may include, for example, a high-resistance conductor containing tungsten, molybdenum, or the like. The dimensions of the heating 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. The heating resistor may also be made of, for example, conductive ceramic containing tungsten carbide. In this case, the thermal expansion difference between the ceramic body and the heating resistor can be reduced. This reduces the thermal stress between the ceramic body and the heating resistor, thereby improving the durability of the heater 120.

[0013] The heaters 120 are inserted into the recesses 113, respectively. That is, by being inserted into the recesses 113, the heaters 120 are arranged perpendicular to the upper surface 110a of the heating plate 110, which is the heating surface.

[0014] In this way, by arranging the heaters 120 perpendicular to the heating surface of the heating plate 110, it is possible to suppress variations in the distance between the heaters 120 and the heating surface, thereby improving the temperature uniformity within the upper surface 110a of the heating plate 110, which is the heating surface.

[0015] The plurality of recesses 113 into which the plurality of heaters 120 are respectively inserted are formed at a non-uniform density on the lower surface 110b of the heating plate 110, which is the opposite side to the heating surface. In Figure 2, the upper surface 110a of the heating plate 110, which is the heating surface, is shown as a rectangular plate, and the positions at which the plurality of recesses 113 are formed are also shown. That is, the recesses 113 are formed sparsely in the central part of the lower surface 110b, and the recesses 113 are formed densely in the peripheral part of the lower surface 110b. In other words, the plurality of recesses 113 are formed so that the density of the recesses 113 is lower near the center of the lower surface 110b and higher near the peripheral edge.

[0016] In this way, by adjusting the density of the recesses 113 on the lower surface 110b opposite the heating surface of the heating plate 110, the density of the heaters 120 inserted into the recesses 113 can be adjusted. As a result, the temperature uniformity within 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 lower surface 110b of the heating plate 110 are more likely to lose heat to the ambient atmosphere around the heating plate 110 than the central portion. Therefore, the temperature of the peripheral portions of the upper surface 110a and 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 recesses 113 on the peripheral portion of the lower surface 110b, the density of the heaters 120 can also be increased, thereby relatively increasing the amount of heat generated at the peripheral portion of the upper surface 110a. This compensates for the amount of heat lost to the ambient atmosphere, thereby further improving the temperature uniformity.

[0017] In a conventional heating device in which multiple heaters (e.g., cartridge heaters) are inserted into multiple holes in the side of a mold, if a malfunction such as a wire breakage occurs in one cartridge heater during heating, a linear low-temperature region may be created along the cartridge heater. This can result in uneven temperatures in the heated object. In contrast, the heating device 100 according to the present embodiment can narrow the low-temperature region even if a malfunction such as a wire breakage occurs in one heater 120 during heating. Furthermore, the heating device 100 according to the present embodiment can uniformly heat the heated object by controlling the output of heaters 120 adjacent to the malfunctioning heater 120. Furthermore, the heating device 100 according to the present embodiment can heat not only the entire heating device 100 but also localized regions by controlling the output of individual heaters for each desired region. This allows for more intense heating of a desired region of the heated object or heating multiple heated objects at different temperatures, thereby enabling the simultaneous heat treatment of multiple products.

[0018] The arrangement of the recesses 113 is not limited to that shown in Fig. 2. For example, if a heat spot with a higher temperature than other regions occurs on the upper surface 110a of the heating plate 110, which is the heating surface, a plurality of recesses 113 may be formed so that the density of the recesses 113 is lower in the region of the lower surface 110b corresponding to the heat spot.

[0019] The fixing plate 130 is, for example, a metal plate-like member, and has a plurality of heaters 120 fixed thereto.

[0020] The support plate 150 is fixed to the fixing plate 130 by a plurality of pillar members 151 while being spaced apart from the fixing plate 130. By positioning the support plate 150 away from the fixing plate 130, it is possible to ensure a space between the support plate 150 and the fixing plate 130 for arranging power supply terminals 122 and 123 (described below) of the plurality of heaters 120. Note that the support plate 150 and the plurality of pillar members 151 may be omitted as necessary.

[0021] Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 2. Note that the support plate 150 and the plurality of columnar members 151 are omitted from Figs. 3 and 4.

[0022] As shown in FIGS. 3 and 4, the heating device 100 is configured by fixing a plurality of heaters 120 to a fixing plate 130 and inserting them into a plurality of recesses 113 of a heating plate 110, respectively.

[0023] The heating plate 110 includes a first plate member 111 and a second plate member 112 .

[0024] The first plate member 111 is a plate-like 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 joining members 114, such as bolts. In other words, the lower surface 111a of the first plate member 111, which is opposite to the upper surface 110a, is a joining surface that is joined to the second plate member 112.

[0025] The second plate member 112 is a plate-like member having an upper surface 112a which serves as a joining surface to be joined to the joining 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.

[0026] Each of the multiple recesses 113 is formed by a corresponding one of the multiple through holes 112b and the lower surface 111a of the first plate member 111 exposed from each of the multiple through holes 112b. That is, the inner wall surface of each through hole 112b forms the inner side 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 multiple heaters 120 contact the lower surface 111a of the first plate member 111 when the multiple heaters 120 are inserted into the multiple recesses 113, respectively. By contacting the tips 120a of the multiple heaters 120 with the lower surface 111a in this manner, the positions of the tips 120a can be aligned on the same plane as the lower surface 111a. Therefore, the distance between the multiple heaters 120 and the heating surface can be made uniform to a distance corresponding to the thickness of the first plate member 111, and as a result, the temperature uniformity within the upper surface 110a of the heating plate 110, which is the heating surface, can be improved.

[0027] Regarding contact between the tip 120a of the heater 120 and the lower surface 111a of the first plate member 111, for example, if the tip 120a of the heater 120 has a rounded hemispherical shape, only the tip of the hemisphere may be in contact with the lower surface 111a of the first plate member 111. Also, for example, if the heater 120 is cylindrical and has an end face at the tip 120a, the end face of the tip 120a of the heater 120 may be in surface contact with the lower surface 111a of the first plate member 111. In this case, the temperature rise rate can be increased. Also, a side portion (edge ​​portion) of the end face may be in contact with the lower surface 111a of the first plate member 111. In this case, the temperature rise rate can be increased and stress can be reduced. Furthermore, the tip 120a of the heater 120 and the underside 111a of the first plate member 111 may be spaced apart when not in use in a room temperature environment, and may be positioned so as to come into contact with each other due to thermal expansion of the heater 120 when in use (when heated).

[0028] 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 into and fixed to the fixing holes 130a, respectively. Specifically, an internal thread is formed on a portion of the inner wall of each fixing hole 130a. Meanwhile, a cylindrical mounting member 121 is attached to the outer circumferential surface of each heater 120, and an external thread 121a is formed on a portion of the outer circumferential surface of the mounting member 121. When each heater 120 is inserted into each fixing hole 130a, the external thread 121a fits into the internal thread of each fixing hole 130a, thereby fixing the plurality of heaters 120 to the fixing plate 130.

[0029] The fixing plate 130 is disposed at a distance from the heating plate 110. As shown in Fig. 4, the fixing plate 130 is connected to the heating plate 110 (second plate member 112) by connecting members 131 such as bolts, with a gap formed between the fixing plate 130 and the heating plate 110. By separating the fixing plate 130 from the heating plate 110 in this manner, it is possible to suppress a rise in temperature of the portions where the multiple heaters 120 are fixed to the fixing plate 130 (for example, portions where the mounting members 121 are attached). On the other hand, the amount of heat removed from the heating plate 110 by the fixing plate 130 is reduced, which makes it possible to promote a rise in temperature of the heating plate 110.

[0030] Furthermore, a spacer member 140 is disposed between the heating plate 110 and the fixed plate 130. The spacer member 140 is cylindrical, and the connecting member 131 is inserted through the spacer member 140. By providing the spacer member 140 between the heating plate 110 and the fixed plate 130, the possibility of collision between the fixed plate 130 and the heating plate 110 can be reduced.

[0031] The material of the spacer member 140 is preferably, for example, a heat-resistant ceramic. For example, oxide ceramics, nitride ceramics, or carbide ceramics can be used as the material of the spacer member 140. This reduces the thermal expansion and contraction of the spacer member 140, thereby reducing wear of the spacer member 140.

[0032] The heaters 120 have base ends 120b positioned farther from the upper surface 110a of the heating plate 110 (the heating surface) than the lower surface of the fixing plate 130 opposite the heating plate 110. Power supply terminals 122, 123 that supply power to the heaters 120 are provided at the base ends 120b. In other words, the base ends 120b of the heaters 120 protrude in a direction away from the upper surface 110a of the heating plate 110 (the heating surface) than the lower surface of the fixing plate 130, and the power supply terminals 122, 123 are provided at the base ends 120b. By providing the power supply terminals 122, 123 at the base ends 120b that protrude in a direction away from the upper surface 110a of the heating plate 110 (the heating surface), the power supply terminals 122, 123 can be spaced farther from the heating surface. As a result, the power supply terminals 122, 123 can be protected from the heat of the heating surface.

[0033] <Modification of the first embodiment> Next, various modified examples of the first embodiment will be described with reference to Fig. 5. In the following description, the same reference numerals will be used to designate components common to the first embodiment, and detailed description thereof will be omitted.

[0034] Fig. 5 is a cross-sectional view of a heating device 100 according to Modification 1 of the first embodiment. The heating device 100 shown in Fig. 5 differs from the heating device 100 shown in Figs. 1 to 4 mainly in the structure of the heating plate and the manner in which multiple heaters are inserted. 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.

[0035] The first plate member 111 is a plate-like 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 joining members 114, such as bolts, with a heat insulating member 115 disposed between the first plate member 111 and the second plate member 112. That is, the lower surface 111a of the first plate member 111, opposite the upper surface 110a, is a joining surface that is joined to the second plate member 112. A plurality of recesses 111b are formed in the lower surface 111a of the first plate member 111, opposite the heating surface.

[0036] The second plate member 112 is a plate-like member having an upper surface 112a which serves as a joining surface to be joined to the joining 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 second plate member 112 at positions corresponding to the plurality of recesses 111b.

[0037] 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 heat insulating fiber, and has the function of limiting the transfer of heat from the first plate member 111 side to the second plate member 112 side. A plurality of through holes 115a are formed in the heat insulating member 115 at positions corresponding to the plurality of recesses 111b.

[0038] The material of the heat insulating member 115 is preferably, for example, ceramics having heat insulating properties. For example, oxide ceramics, nitride ceramics, carbide ceramics, or the like can be used as the material of the heat insulating member 115.

[0039] Each of the plurality of recesses 113 is formed by a corresponding one of the plurality of through holes 112b, a corresponding one of the plurality of through holes 115a, and a plurality of recesses 111b. That is, the inner surfaces of each of the through holes 112b, the inner surfaces of each of the through holes 115a, and the inner surfaces of each of the recesses 111b form the inner surface of each of the recesses 113, and the bottom surfaces of each of the recesses 111b form the bottom surfaces of each of the recesses 113. Then, with the plurality of heaters 120 inserted into the plurality of recesses 113, the tips 120a of the plurality of heaters 120 are positioned in the plurality of recesses 111b.

[0040] By positioning the tips 120a of the multiple heaters 120 within the multiple recesses 111b, for example, when each of the multiple heaters 120 has a maximum heat generation point where the temperature is maximum, the maximum heat generation point can be brought close to the upper surface 110a of the heating plate 110, which is the heating surface. As a result, the heating device 100 according to the first modification can efficiently heat the upper surface 110a of the heating plate 110, which is the heating surface. Furthermore, by positioning the tips 120a of the multiple heaters 120 within the multiple recesses 111b, the maximum heat generation point can be moved away from the base ends 120b of the multiple heaters 120. As a result, the heating device 100 according to the first modification makes it difficult for heat to be transferred from the maximum heat generation point to the power supply terminals 122 and 123 provided at the base ends 120b of the multiple heaters 120, and therefore deterioration of the power supply terminals 122 and 123 can be suppressed.

[0041] The tips 120a of the heaters 120 may or may not be in contact with the bottom surface of each recess 111b.

[0042] The fixing plate 130 is connected to the heating plate 110 via a columnar connecting metal fitting 160 having a predetermined length, and is disposed at a distance from the heating plate 110. The length of the connecting metal fitting 160 can be made longer than the thickness of the spacer member 140 shown in FIG.

[0043] FIG. 6 is a side view of a heating device 100 according to Modification 2 of the first embodiment. FIG. 7 is a cross-sectional view of the heating device 100 according to Modification 2 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, the heating device 100 shown in FIGS. 6 and 7 differs from the heating device 100 shown in FIGS. 1 to 4 in that the heating plate 110 is not divided into two members, a first plate member 111 and a second plate member 112. Specifically, as shown in FIGS. 6 and 7, the portions of the heating plate 110 corresponding to the first plate member 111 and the second plate member 112 are integrally formed from metal plate-like members. As a result, the heating device 100 according to Modification 2 can simplify the manufacturing process of the heating device 100.

[0044] As described above, the heating device (e.g., heating device 100) according to the first embodiment includes a heating plate (e.g., heating plate 110) and multiple heaters (e.g., heaters 120). The heating plate has a heating surface (e.g., upper surface 110a) and is provided with multiple recesses (e.g., recesses 113) on the back surface (e.g., lower surface 110b) opposite the heating surface. The multiple heaters are located in the multiple recesses, respectively. This improves the uniformity of heat distribution across the heating surface.

[0045] The heating plate according to the first embodiment is a metal member, and the heaters are ceramic heaters each having a ceramic body and a heating resistor located inside the ceramic body. This can prevent seizure between the metal heating plate and the heater.

[0046] The heating plate according to the first embodiment includes a first plate member (e.g., first plate member 111) and a second plate member (e.g., second plate member 112). The first plate member has a heating surface and a bonding surface (e.g., lower surface 111a) located opposite the heating surface. The second plate member has a bonded surface bonded to the bonding surface, a back surface located opposite the bonded surface, and a plurality of through holes (e.g., through holes 112b) penetrating from the back surface to the bonded surface. Each of the plurality of recesses is formed by a corresponding one of the plurality of through holes and the bonding surface. The tips (e.g., tip 120a) of the plurality of heaters are in contact with the bonding surface. This allows the distance between the plurality of heaters and the heating surface to be uniform to a distance corresponding to the thickness of the first plate member, thereby improving the temperature uniformity within the heating surface.

[0047] The heating device according to the first embodiment further includes a fixing plate (for example, fixing plate 130). Fixing plate 130 fixes the heaters at positions separated from the heating plate. This prevents the heaters from rising in temperature at the fixing plate and promotes the heating plate to rise in temperature.

[0048] Moreover, the heating device according to the first embodiment further includes a spacer member (for example, spacer member 140) between the heating plate and the fixing plate, which can reduce the possibility of collision between the fixing plate and the heating plate.

[0049] Furthermore, the spacer member according to the first embodiment is made of ceramic, which reduces wear of the spacer member.

[0050] The fixing plate according to the first embodiment also has a plurality of fixing holes (e.g., fixing hole 130a) at positions corresponding to the plurality of recesses, through which the plurality of heaters are inserted and fixed. The plurality of heaters have base ends (e.g., base end 120b) at positions farther from the heating surface than the rear surface of the fixing plate opposite the heating plate. The base ends are provided with power supply terminals (e.g., power supply terminals 122, 123) that supply power to the plurality of heaters. This allows the power supply terminals to be protected from the heat of the heating surface.

[0051] The heating device according to the first embodiment further includes a support plate (for example, support plate 150). The support plate is fixed to the fixing plate by a plurality of pillar members (for example, pillar members 151) while being spaced apart from the fixing plate. This makes it possible to ensure a space between the support plate and the fixing plate for arranging power supply terminals for the plurality of heaters.

[0052] Furthermore, the recesses according to the first embodiment are densely packed in a portion in the surface direction and sparsely packed in another portion of the back surface, which can further improve the uniformity of heat within the heating surface.

[0053] The heating device according to the first embodiment is a mold heating device, which can improve the temperature uniformity within the heating surface used to heat the mold.

[0054] The heating plate according to the first embodiment includes a first plate member, a second plate member, and a heat insulating member (e.g., heat insulating member 115). The first plate member has a heating surface, a bonding surface (e.g., lower surface 111a) opposite the heating surface, and a plurality of first recesses (111b) located on the bonding surface. The second plate member has a bonded surface to be bonded to the bonding surface, a back surface opposite the bonded surface, and a plurality of first through holes (e.g., through holes 112b) that correspond to the first recesses and penetrate from the back surface to the bonded surface. The heat insulating member is located between the first plate member and the second plate member and has a plurality of second through holes (e.g., through holes 115a) that correspond to the first recesses. Each of the recesses is made up of a respective one of the first through holes, a respective one of the second through holes, and a respective one of the first recesses. The tips of the heaters are in contact with the first recesses. This allows the heating surface to be heated efficiently, and also prevents deterioration of the power supply terminals provided at the base ends of the plurality of heaters.

[0055] 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 line XX in Fig. 9. In the following description, the same reference numerals are used to designate components common to the first modification of the first embodiment, and detailed description thereof will be omitted.

[0056] The heating device 100A shown in Figures 8 to 10 differs from the heating device 100 according to Variation 1 of the first embodiment shown in Figure 5 mainly in the structure of the connecting members and the positional relationship between the connecting members and the joining members. The heating plate 110 of the heating device 100A shown in Figures 8 to 10 has a first plate member 111, a second plate member 112, and a heat insulating member 115, similar to the heating plate 110 of the heating device 100 shown in Figure 5.

[0057] The second plate member 112 is a plate-like member having an upper surface 112a, which serves as a joining surface to be joined to the joining 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 has screw holes 112c formed therein, which penetrate the upper surface 112a and the lower surface 110b. For example, the second plate member 112 has a plurality of (here, four) screw holes 112c formed therein. An internal thread is formed on the inner wall surface of each screw hole 112c.

[0058] The fixing plate 130A has a plurality of heaters 120 fixed thereto and is disposed at a distance from the second plate member 112. As shown in Figures 9 and 10, the fixing plate 130A is connected to the second plate member 112 by connecting members 131A such as bolts, with a gap formed between the fixing plate 130A and the heating plate 110. For example, the fixing plate 130A is connected to the second plate member 112 by a plurality of (here, four) connecting members 131A.

[0059] The connecting member 131A has a tip 131Aa formed with a male thread that can fit into the female thread of the screw hole 112c of the second plate member 112. The tip 131Aa of the connecting member 131A fits into the screw hole 112c of the second plate member 112 and extends toward the first plate member 111 by a length that does not penetrate the heat insulating member 115. In this embodiment, the tip 131Aa of the connecting member 131A extends in the screw hole 112c from the lower surface 110b of the second plate member 112 to a position that reaches the upper surface 112a, and is in contact with the surface of the heat insulating member 115 that is exposed from the screw hole 112c.

[0060] In this way, by extending tip 131Aa of connecting member 131A toward first plate member 111 without penetrating heat insulating member 115, it is possible to avoid contact between connecting member 131A and first plate member 111. As a result, it is possible to suppress heat conduction from first plate member 111, which has upper surface 110a as the heating surface, to connecting member 131A.

[0061] Furthermore, by bringing the tips 131Aa of the connecting members 131A into contact with the surface of the heat insulating member 115, the positions of the tips 131Aa of the multiple connecting members 131A can be aligned on the same plane as the surface of the heat insulating member 115. This makes it possible to uniformize the length of the heat transfer path from the first plate member 111 to the tips 131Aa of the multiple connecting members 131A, and as a result, the thermal uniformity of the first plate member 111 can be improved.

[0062] Furthermore, 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 is cylindrical and surrounds the outer periphery of the portion of the connecting member 131A located between the fixed plate 130A and the second plate member 112, and is in contact with the fixed plate 130A and the second plate member 112. A gap may or may not be provided between the inner circumferential surface of the spacer member 140A and the outer circumferential surface of the connecting member 131A. By surrounding the outer periphery of the connecting member 131A with the cylindrical spacer member 140A, it is possible to suppress the heat of the connecting member 131A from being released into the space surrounding the connecting member 131A.

[0063] The spacer member 140A may be made of a metal such as stainless steel, which improves the durability of the spacer member 140A and allows the distance between the fixed plate 130A and the second plate member 112 to be maintained constant.

[0064] 9 and 10, the second plate member 112 is joined to the first plate member 111 by joining members 114A such as bolts, with a heat insulating member 115 disposed between the first plate member 111 and the second plate member 112. For example, the second plate member 112 is joined to the first plate member 111 by a plurality of (here, four) joining members 114A.

[0065] Incidentally, the first plate member 111 having the upper surface 110a, which is the heating surface, and the second plate member 112 are thermally connected via the joining member 114A. In order to further suppress the heat conduction from the first plate member 111 to the connecting member 131A, it is important that the positional relationship between the connecting member 131A and the joining member 114A is such that the heat transfer path from the joining member 114A to the connecting member 131A is as long as possible.

[0066] 9, in the heating device 100A according to this embodiment, the connecting member 131A is positioned so as not to overlap with the joining member 114A in a plan view. This lengthens the heat transfer path from the joining member 114A to the connecting member 131A, and as a result, it is possible to further suppress the heat transfer from the first plate member 111 to the connecting member 131A via the joining member 114A.

[0067] 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. By positioning 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 bypasses the recess 113. This makes it possible to further suppress heat transfer from the first plate member 111 to the connecting member 131A via the joining member 114A. Note that the number of 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.

[0068] Moreover, the connecting member 131A is located closer to the center of the second plate member 112 than the joining member 114A in plan view and side view. As a result, a position close to the center of the heating plate 110 is supported by the connecting member 131A, and therefore, deflection of the center of the heating plate 110 due to its own weight can be suppressed. Furthermore, since the joining member 114A is located 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.

[0069] Incidentally, the portion of the first plate member 111 located near the joining members 114A is more likely to lose heat to the joining members 114A than other portions. Therefore, the portion of the first plate member 111 located near the joining members 114A may have a lower temperature than other portions. If the temperature of the portion of the first plate member 111 located near the joining members 114A becomes lower, the thermal uniformity of the first plate member 111 may be impaired.

[0070] 9, in the heating device 100A according to this embodiment, the bonding members 114A are located more inward than the recesses 113 that are closest to the periphery of the lower surface 110b (see FIG. 10) among the plurality of recesses 113 in a plan view. As a result, the periphery of the bonding members 114A is surrounded by the plurality of recesses 113, and therefore the portion of the first plate member 111 located near the bonding members 114A is heated by the plurality of heaters 120 inserted into the plurality of recesses 113, respectively. As a result, it is possible to suppress a temperature drop in the portion of the first plate member 111 located near the bonding members 114A, and it is possible to maintain the thermal uniformity of the first plate member 111.

[0071] 10 , the joining member 114A penetrates the heat insulating member 115 and has a spacer member 170 on the outer periphery of the penetrated portion. The spacer member 170 is cylindrical and surrounds the 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 circumferential surface of the spacer member 170 and the outer circumferential surface of the joining member 114A. By surrounding the outer periphery of the joining member 114A with the cylindrical spacer member 170, it is possible to suppress the transfer of heat from the joining member 114A to the heat insulating member 115.

[0072] The spacer members 170 are preferably made of, for example, ceramics with relatively high thermal insulation properties. For example, oxide ceramics, nitride ceramics, or carbide ceramics can be used as the material for the spacer members 170. This can further suppress heat transfer from the joining members 114A to the heat insulating members 115.

[0073] <Modification of the second embodiment> Next, various modified examples of the second embodiment will be described with reference to Figures 11 to 13. In the following description, the same components as those in the second embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted.

[0074] Fig. 11 is a cross-sectional view of a heating device 100A according to Modification 1 of Embodiment 2. The heating device 100A shown in Fig. 11 differs from the heating device 100A shown in Figs. 8 to 10 mainly in the structure of a tip 131Aa of a connecting member 131A.

[0075] 11 extends from the lower surface 110b of the second plate member 112 to a position in the screw hole 112c but does not reach the upper surface 112a. The tip 131Aa of the connecting member 131A forms a gap 112d between the end face of the tip 131Aa and the surface of the heat insulating member 115 exposed from the screw hole 112c.

[0076] 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 the gap 112d between the end face of the tip 131Aa of the connecting member 131A and the surface of the heat insulating member 115, it is possible to suppress heat conduction from the heat insulating member 115 to the connecting member 131A. As a result, it is possible to suppress 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.

[0077] Fig. 12 is a cross-sectional view of a heating device 100A according to Modification 2 of the second embodiment. The heating device 100A shown in Fig. 12 differs 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.

[0078] 12 extends from the lower surface 110b of the second plate member 112 to a position in the screw hole 112c but not to reach the upper surface 112a. 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.

[0079] In this way, by bringing a part of the heat insulating member 115 filling the screw hole 112c into contact with the tip 131Aa of the connecting member 131A, it is possible to locally increase the thickness of the heat insulating member 115 at the position corresponding to the tip 131Aa of the connecting member 131A. As a result, it is possible to suppress 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.

[0080] Fig. 13 is a cross-sectional view of a heating device 100A according to Modification 3 of Embodiment 2. The heating device 100A shown in Fig. 13 differs from the heating device 100A shown in Figs. 8 to 10 mainly in the structure of a tip 131Aa of a connecting member 131A.

[0081] 13 projects from the screw hole 112c toward the heat insulating member 115, extends in the direction of the first plate member 111, and is embedded inside the heat insulating member 115. As shown in FIG.

[0082] By embedding the tip 131Aa of the connecting member 131A inside the heat insulating member 115 in this manner, it is possible to prevent the heat insulating member 115 from shifting in position.

[0083] As described above, the heating device (e.g., heating device 100A) according to the second embodiment further includes a fixing plate (e.g., fixing plate 130A) and a connecting member (e.g., connecting member 131A). The fixing plate fixes a plurality of heaters (e.g., heaters 120) at a position spaced apart from a second plate member (e.g., second plate member 112). The connecting member connects the fixing plate to the second plate member. The tip of the connecting member is engaged with a screw hole (e.g., screw hole 112c) provided in the second plate member, and extends toward the first plate member by a length not penetrating the heat insulating member (e.g., heat insulating member 115). This makes it possible to suppress heat conduction from the first plate member (e.g., first plate member 111) having the heating surface to the connecting member.

[0084] Furthermore, the tip of the connecting member according to the second embodiment extends from the back surface (e.g., lower surface 110b) of the screw hole to a position that reaches the joined surface (e.g., upper surface 112a) and contacts the surface of the heat insulating member exposed from the screw hole. This makes it possible to equalize the length of the heat transfer path from the first plate member to the tips of the multiple connecting members, thereby improving the thermal uniformity of the first plate member.

[0085] Furthermore, the connecting member according to the second embodiment may extend from the rear surface of the screw hole to a position not reaching the joined surface, and may be positioned away from the surface of the heat insulating member exposed through the screw hole, thereby suppressing heat conduction from the first plate member having the heating surface to the connecting member via the heat insulating member.

[0086] Furthermore, the tip of the connecting member according to the second embodiment may extend from the rear surface of the screw hole to a position not reaching the joined surface and contact a part of the heat insulating member filled in the screw hole, thereby suppressing heat conduction from the first plate member having the heating surface to the connecting member via the heat insulating member.

[0087] Furthermore, the tip of the connecting member according to the second embodiment may protrude from the screw hole toward the heat insulating member, extend toward the first plate member, and be embedded inside the heat insulating member, thereby preventing the heat insulating member from shifting out of position.

[0088] The heating device according to the second embodiment further includes a joining member (e.g., joining member 114A) that joins the second plate member to the first plate member. The joining member is positioned so as not to overlap with the connecting member in a plan view. This further suppresses heat conduction from the first plate member to the connecting member via the joining member.

[0089] Furthermore, the heating device according to the second embodiment has at least one recess among the multiple recesses between the connecting member and the joining member, which further suppresses heat conduction from the first plate member to the connecting member via the joining member.

[0090] Furthermore, the connecting member according to the second embodiment is located closer to the center of the second plate member than the joining member, which prevents the center of the heating plate from being deflected by its own weight and also prevents heat conduction from the center of the heating plate to the joining member.

[0091] Furthermore, the bonding member according to the second embodiment is located inside the recess closest to the periphery of the rear surface of the first plate member. This allows the portion of the first plate member located near the bonding member to be heated by the heaters inserted into the recesses, thereby preventing a temperature drop in that portion and maintaining uniform temperature throughout the first plate member.

[0092] The joining member according to the second embodiment also includes a first spacer member (for example, spacer member 170). The first spacer member is an annular body that is surrounded by the heat insulating member and is in contact with the first plate member and the second plate member. This prevents heat from being transferred from the joining member to the heat insulating member.

[0093] Furthermore, the first spacer member according to the second embodiment is made of ceramic, which can further suppress the transfer of heat from the joining member to the heat insulating member.

[0094] The connecting member according to the second embodiment also includes a second spacer member (for example, spacer member 140A). The second spacer member is a cylindrical body that is in contact with the fixing plate and the second plate member. This prevents heat from being released into the space around the connecting member.

[0095] Furthermore, the second spacer member according to the second embodiment is made of metal, which improves the durability of the spacer member and enables the distance between the fixed plate and the second plate member to be maintained constant.

[0096] <Third embodiment> 14 is a cross-sectional view of a heating device 100B according to the third embodiment. In the following description, the same components as those in the second embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0097] 14 differs from the heating device 100A shown in FIGS. 8 to 10 in the structure of the first plate member. Specifically, in the heating device 100B shown in FIG. 14, the first plate member 111 has a groove 111c on the lower surface 111a. The groove 111c extends from the periphery of the lower surface 111a toward the center, and the opening at the top is closed by a heat insulating member 115.

[0098] In this way, by providing the grooves 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 heat cycles can be absorbed by the grooves 111c.

[0099] It should be noted that the first plate member 111 may be provided with horizontal or vertical holes instead of the grooves 111c.

[0100] <Fourth embodiment> 15 is a cross-sectional view of a heating device 100C according to the fourth embodiment. In the following description, the same components as those in the third embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0101] The heating device 100C shown in Fig. 15 differs 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 into the groove portion 111c. As the temperature measuring element 180, for example, a thermocouple can be used.

[0102] In this way, by inserting the temperature measuring element 180 into the groove 111c of the first plate member 111, the temperature of the first plate member 111 can be measured.

[0103] Fifth Embodiment Fig. 16 is a side view of a heating device 100D according to a fifth embodiment. Fig. 17 is a cross-sectional view of a heating device 100D according to a fifth embodiment. In the following description, the same reference numerals are used to designate components common to the second modification of the first embodiment, and detailed description thereof will be omitted.

[0104] 16 and 17 differs from the heating device 100 according to Modification 2 of the first embodiment shown in Fig. 6 and 7 mainly in the structure of the fixing plate. Specifically, the fixing plate 130B has a third plate member 132, a fourth plate member 133, and a heat insulating member 135.

[0105] The third plate member 132 is a metal plate-like member having an opposing surface 132a that faces the heating plate 110. The third plate member 132 is joined to the fourth plate member 133 by joining members (not shown), such as bolts, with a heat insulating member 135 disposed between the third plate member 132 and the fourth plate member 133.

[0106] The fourth plate member 133 is a metal plate-like member joined to the rear surface opposite the opposing surface 132a of the third plate member 132. A plurality of heaters 120 are fixed to the fourth plate member 133. Specifically, 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 into the fixing holes 130a, respectively. Specifically, an internal thread is formed on a portion of the inner wall of each fixing hole 130a. A cylindrical mounting member 121 is attached to the outer circumferential surface of each heater 120, and an external thread 121a is formed on a portion of the outer circumferential surface of the mounting member 121. When each heater 120 is inserted into each fixing hole 130a, the external thread 121a engages with the internal thread of each fixing hole 130a, thereby fixing the plurality of heaters 120 to the fourth plate member 133. The third plate member 132 and the heat insulating member 135 are each formed with a through hole corresponding to the fixing hole 130a, through which the heater 120 can be inserted.

[0107] 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 heat insulating fiber, and has the function of limiting the transfer of heat from the third plate member 132 side to the fourth plate member 133 side.

[0108] The material of the heat insulating member 135 is preferably, for example, ceramics having heat insulating properties. For example, oxide ceramics, nitride ceramics, carbide ceramics, or the like can be used as the material of the heat insulating member 135.

[0109] In this way, since the fixing plate 130B has the heat insulating member 135, it is possible to suppress a rise in temperature of the fixing portion of the fixing plate 130B where the plurality of heaters 120 are fixed (for example, the portion where the mounting member 121 is attached).

[0110] Sixth Embodiment Fig. 18 is a side view of a heating device 100E according to a sixth embodiment. Fig. 19 is a cross-sectional view of a heating device 100E according to the sixth embodiment. In the following description, the same reference numerals are used to designate components common to the second modification of the first embodiment, and detailed description thereof will be omitted.

[0111] The heating device 100E shown in Figures 18 and 19 differs from the heating device 100 according to Modification 2 of the first embodiment shown in Figures 6 and 7 mainly in that it has a heat insulating plate. Specifically, the heating device 100E shown in Figures 18 and 19 has a heat insulating plate 190 located between the heating plate 110 and the fixing plate 130.

[0112] The heat insulating plate 190 has a fifth plate member 191, a sixth plate member 192, and a heat insulating member 195. The fifth plate member 191, 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 fixing plate 130 can be inserted.

[0113] The fifth plate member 191 is a metal plate-like member having an opposing surface 191a that faces the heating plate 110. The fifth plate member 191 is joined to the sixth plate member 192 by joining members (not shown), such as bolts, with a heat insulating member 195 disposed between the fifth plate member 191 and the sixth plate member 192. The fifth plate member 191 is connected to the heating plate 110 via columnar connecting fittings 196 having a predetermined length, and is thereby disposed at a distance from the heating plate 110. The length of the connecting fittings 196 can be longer than the thickness of the spacer members 140 shown in FIGS. 6 and 7, for example.

[0114] The sixth plate member 192 is a metal plate-like member joined to the back surface opposite to the opposing surface 191a of the fifth plate member 191. The sixth plate member 192 is connected to the fixed plate 130 via a columnar connecting metal fitting 197 having a predetermined length, and is thereby disposed at a distance from the fixed plate 130. The length of the connecting metal fitting 197 can be made longer than the thickness of the spacer member 140 shown in Figures 6 and 7, for example.

[0115] 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 heat insulating fiber, and has the function of limiting the transfer of heat from the fifth plate member 191 side to the sixth plate member 192 side.

[0116] The material of the heat insulating member 195 is preferably, for example, ceramics having heat insulating properties. For example, oxide ceramics, nitride ceramics, carbide ceramics, or the like can be used as the material of the heat insulating member 195.

[0117] In this way, by positioning the heat insulating plate 190 between the heating plate 110 and the fixing plate 130, it is possible to suppress a rise in temperature of the fixing plate 130.

[0118] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0119] 100, 100A~100E heating device 110 Heating Plate 110a top side 110b Bottom side 111 first plate member 111a Bottom side 111b recess 111c Groove 112 second plate member 112a Top side 112b Through hole 112c screw hole 112d gap 113 Recess 114, 114A Joint members 115 Heat insulating materials 115a Through hole 120 Heater 120a tip 120b proximal end 121 Mounting material 121a Male thread 122, 123 Power supply terminal 130, 130A, 130B fixing plate 130a fixing hole 131, 131A connecting member 131Aa tip 132 third plate member 132a Opposite side 133 Fourth plate member 135 Heat insulating materials 140, 140A Spacer member 170 Spacer member 180 Temperature measuring element 190 Heat Insulation Plate 191 Fifth Plate Component 191a Opposite side 192 Sixth Plate Component 195 Heat insulating materials

Claims

1. A heating plate; A heat insulating member; a plurality of heaters; The heating plate is a first plate member having a heating surface, a joining surface opposite the heating surface, and a plurality of recesses; a second plate member having a plurality of first through holes positioned corresponding to the plurality of recesses and passing through the second plate member; Including, the heat insulating member is located between the first plate member and the second plate member, and has a plurality of through holes located corresponding to the plurality of recesses; moreover, a fixing plate for fixing the plurality of heaters at a position spaced apart from the second plate member; a connecting member that connects the fixed plate and the second plate member, A heating device, wherein the connecting member has a tip that is engaged with a screw hole provided in the second plate member and extends toward the first plate member by a length that does not penetrate the insulating member.

2. The connecting member is The heating device according to claim 1 , wherein the heat insulating member is positioned away from a surface exposed from the screw hole.

3. a joining member that joins the second plate member to the first plate member; The joining member is The heating device according to claim 1 or 2, which is positioned so as not to overlap the connecting member in a plan view.

4. The heating device according to claim 3 , wherein at least one recess among the plurality of recesses is provided between the connecting member and the joining member.

5. The connecting member is The heating device according to claim 3 or 4, wherein the second plate member is positioned closer to the center of the second plate member than the joining member.

6. The joining member is 6. The heating device according to claim 3, wherein the recess is located inside a recess that is closest to the periphery of the joining surface among the plurality of recesses.

7. The joining member is a first spacer member; The heating device according to any one of claims 3 to 6, 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.

8. The connecting member is a second spacer member; 8. The heating device according to claim 1, wherein the second spacer member is a cylindrical body and is in contact with the fixed plate and the second plate member.

9. 9. The heating device according to claim 1, wherein a part of the plurality of recesses is dense in a surface direction, and another part of the joining surface is coarse.

10. The first plate member comprises: The heating device according to claim 1 , further comprising a groove extending from the periphery of the joining surface toward the center thereof and closed by the heat insulating member.

11. The first plate member comprises: The heating device according to claim 10 , further comprising a temperature measuring element in the groove.

12. The heating device according to any one of claims 1 to 11, which is a mold heating device.

Images