Radiation heater device

Abstract

To provide a radiation heater device capable of increasing the amount of radiant heat emitted.SOLUTION: A radiation heater device 10 includes a heater element 20 having a sheet-like substrate 21 and a heater wire 22 arranged on the substrate 21, a first radiation sheet 60 arranged on a first surface side of the heater element 20 and made of flame-resistant fiber, and a heat transfer sheet (first heat transfer sheet 30) interposed between the heater element 20 and the first radiation sheet 60.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a radiant heater device. [Background technology]

[0002] Patent Document 1 discloses a radiant heater having a radiant surface material and a heater element, in which the radiant surface material and the heater element are integrated, and the radiant surface material is made of a fabric body made of flame-resistant fibers. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7264707 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, since flame-resistant fibers have low thermal conductivity, the area directly under the heater wire constituting the heater element is heated, but the heat is not easily transmitted to other areas, so an increase in the amount of radiant heat is inhibited.

[0005] Therefore, an object of the present disclosure is to provide a radiant heater device capable of increasing the amount of radiant heat emitted. [Means for solving the problem]

[0006] A radiant heater device according to one aspect of the present disclosure comprises a heater element having a sheet-like substrate and a heater wire arranged on the substrate, a radiant sheet made of flame-retardant fiber and arranged on a first surface side of the heater element, and a heat transfer sheet interposed between the heater element and the radiant sheet. Effect of the Invention

[0007] According to the present disclosure, a radiant heater device capable of increasing the amount of radiant heat emitted can be provided. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of use of the radiant heater device according to the first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing an installation structure of the radiant heater device according to the first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing a schematic configuration of the radiant heater device according to the first embodiment. [Figure 4] FIG. 4 is a plan view showing an example of the arrangement of the ends of the first radiation sheet according to the first embodiment. [Diagram 5] FIG. 5 is a plan view showing an example of the arrangement of the ends of the first radiation sheet according to the first embodiment. [Figure 6] FIG. 6 is a table showing the temperature of each part and the amount of radiation heat emitted in the radiant heater device according to the first embodiment and a radiant heater device as a comparative example. [Figure 7] FIG. 7 is a cross-sectional view showing a schematic configuration of a radiant heater device according to the second embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a schematic configuration of a radiant heater device according to a third embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing a schematic configuration of a radiant heater device according to the fourth embodiment. [Figure 10] FIG. 10 is a cross-sectional view showing a schematic configuration of a radiant heater device according to the fifth embodiment. [Figure 11] FIG. 11 is a cross-sectional view showing a schematic configuration of a radiant heater device according to a sixth embodiment. [Figure 12] FIG. 12 is a cross-sectional view showing a schematic configuration of a radiant heater device according to a seventh embodiment. [Figure 13] FIG. 13 is a cross-sectional view showing a schematic configuration of a radiant heater device according to an eighth embodiment. [Figure 14] FIG. 14 is an enlarged cross-sectional view showing a part of the radiant heater device according to the ninth embodiment. [Figure 15] FIG. 15 is an enlarged cross-sectional view showing a part of the radiant heater device according to the tenth embodiment. [Figure 16]FIG. 16 is an enlarged cross-sectional view showing a part of the radiant heater device according to the eleventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A radiant heater device according to one aspect of the present disclosure comprises a heater element having a sheet-like substrate and a heater wire arranged on the substrate, a radiant sheet made of flame-retardant fiber and arranged on a first surface side of the heater element, and a heat transfer sheet interposed between the heater element and the radiant sheet.

[0010] According to this, since the heat transfer sheet is interposed between the heater element and the radiation sheet, the heat from the heater wire can be spread in a flat manner by the heat transfer sheet. This makes it possible to reduce the temperature difference between the heater wire and the area of ​​the base material where the heater wire is not arranged, and allows for even heat generation. Therefore, the amount of radiation heat can be increased.

[0011] Furthermore, when the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, D>Tc may be satisfied.

[0012] According to this, since the thickness Tc of the heat transfer sheet is smaller than the diameter D of the heater wire, the heat transfer sheet can be arranged so as to wrap around the heater wire. This makes it possible to reduce gaps around the heater wire and efficiently transfer heat from the heater wire to the heat transfer sheet.

[0013] Furthermore, when the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, Tc may be greater than D.

[0014] According to this, since the thickness Tc of the heat transfer sheet is larger than the diameter D of the heater wire, the heat transfer sheet is less likely to deform along the outer shape of the heater wire. Therefore, a gap can be formed around the heater wire. The insulating effect of this gap can suppress unnecessary heat transfer, making it possible to improve efficiency. In addition, this gap reduces the adhesive area between the heater wire and the heat transfer sheet, but even if localized heat transfer occurs, the thickness Tc of the heat transfer sheet is larger than the diameter D of the heater wire, so the heat can be uniformly distributed by the heat transfer sheet. In addition, since the amount of heat transfer from the heater wire is suppressed by the gap around the heater wire, it is also possible to suppress a decrease in adhesive strength between the layers of the radiation sheet and the heat transfer sheet.

[0015] Furthermore, when the thickness of the radiation sheet is Tf and the thickness of the heat transfer sheet is Tc, Tc may be greater than Tf.

[0016] According to this, since the thickness Tf of the radiation sheet is smaller than the thickness Tc of the heat transfer sheet, the radiation sheet can be laminated along the unevenness of the heat transfer sheet. This makes it possible to reduce the gap between the heat transfer sheet and the radiation sheet, and also makes it possible to efficiently transfer heat from the heat transfer sheet to the radiation sheet.

[0017] Furthermore, when the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, the relationship D>Tc>Tf may be satisfied.

[0018] According to this, since the thickness Tc of the heat transfer sheet is smaller than the diameter D of the heater wire, the heat transfer sheet can be arranged so as to wrap around the heater wire. Therefore, the gap around the heater wire can be suppressed, and the heat of the heater wire can be efficiently transferred to the heat transfer sheet. Furthermore, since the thickness Tf of the radiation sheet is smaller than the thickness Tc of the heat transfer sheet, the radiation sheet can be laminated along the unevenness of the heat transfer sheet. This makes it possible to suppress the gap between the heat transfer sheet and the radiation sheet, and also makes the heat transfer from the heat transfer sheet to the radiation sheet more efficient. As a result, the overall amount of radiation heat can be increased.

[0019] Furthermore, when the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, the relationship Tf>D>Tc may be satisfied.

[0020] According to this, since the thickness Tc of the heat transfer sheet is smaller than the diameter D of the heater wire, the heat transfer sheet can be arranged so as to wrap around the heater wire. Therefore, it is possible to suppress the gap around the heater wire, and the heat of the heater wire can be efficiently transferred to the heat transfer sheet. Furthermore, since the thickness Tf of the radiation sheet is larger than the diameter D of the heater wire, the radiation sheet is less likely to deform along the outer shape of the heater wire. Therefore, a gap is likely to be formed between the heat transfer sheet and the radiation sheet around the heater wire. Since this gap suppresses the amount of heat transfer from the heater wire, it is possible to suppress the decrease in adhesive strength between the layers of the radiation sheet and the heat transfer sheet. Furthermore, the heat capacity of the radiation sheet makes it difficult for the temperature to rise, and the adhesive strength can be maintained. As a result, the reliability of the radiant heater device can be improved.

[0021] Furthermore, when the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, the relationship Tc>D>Tf may be satisfied.

[0022] According to this, since the thickness Tc of the heat transfer sheet is larger than the diameter D of the heater wire, the heat transfer sheet is less likely to deform along the outer shape of the heater wire. Therefore, a gap can be formed around the heater wire. The insulating effect of this gap can suppress unnecessary heat transfer, making it possible to improve efficiency. In addition, this gap reduces the adhesive area between the heater wire and the heat transfer sheet, but even if localized heat transfer occurs, the thickness Tc of the heat transfer sheet is larger than the diameter D of the heater wire, so the heat transfer sheet can achieve uniform heating. Since the amount of heat transfer from the heater wire is suppressed by the gap around the heater wire, it is also possible to suppress a decrease in adhesive strength between the layers of the radiation sheet and the heat transfer sheet. In addition, the heat capacity of the heat transfer sheet makes it difficult for the temperature to rise, so the adhesive strength can be maintained and reliability can be improved. Furthermore, since the thickness Tf of the radiation sheet is smaller than the thickness Tc of the heat transfer sheet, the radiation sheet can be laminated along the unevenness of the heat transfer sheet. This makes it possible to reduce the gap between the heat transfer sheet and the radiation sheet, and also makes it possible to efficiently transfer heat from the heat transfer sheet to the radiation sheet.

[0023] The radiant heater device may further include a heat insulating material disposed on a second surface side of the heater element opposite to the first surface.

[0024] According to this, since the heat insulating material is disposed on the second surface side of the heater element, the heat insulating material can prevent heat from the heater element from being directed toward the second surface side.

[0025] The heat insulating material may be made of any one of glass wool, urethane foam, urethane sponge, melamine resin, and polystyrene foam.

[0026] According to this, the insulating material is made of one of glass wool, urethane foam, urethane sponge, melamine resin, and polystyrene foam, so that a high insulating effect can be achieved.

[0027] The heater wire may be covered with an insulating material.

[0028] According to this, since the heater wire is covered with an insulating material, electrical conduction between the heater wire and the heat transfer sheet can be prevented, and electrical stability can be achieved.

[0029] The heater wire may be made of one of a Cu-Ag based alloy and a Cu-Mg based alloy.

[0030] According to this, since the heater wire is formed from either a Cu-Ag based alloy or a Cu-Mg based alloy, effective heat generation is possible.

[0031] The substrate may be made of either a nonwoven fabric or urethane.

[0032] According to this, since the base material is formed from either nonwoven fabric or urethane, the heat resistance of the base material can be improved.

[0033] The radiation sheet may have an emissivity of 0.6 or more.

[0034] According to this, the emissivity of the radiation sheet is 0.6 or more, so that it is possible to enhance the radiation effect.

[0035] A heat transfer sheet may be attached to the heater element and the radiation sheet.

[0036] According to this, since the heat transfer sheet is bonded to the heater element and the radiation sheet, the structure can be stabilized.

[0037] [Embodiment Mode] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that each of the embodiments described below shows a specific example of the present disclosure. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components that are not described in the independent claims showing the highest concept will be described as optional components.

[0038] In addition, expressions indicating relative directions or attitudes, such as "parallel" and "orthogonal," may not strictly mean that direction or attitude. For example, "two directions are orthogonal" does not only mean that the two directions are completely orthogonal, but also means that the two directions are substantially orthogonal, that is, that there is a difference of, for example, about a few percent. This also applies to expressions that compare objects, such as "equivalent."

[0039] First Embodiment (Example of using a radiant heater) First, with reference to FIG. 1, an example of use of the radiant heater device 10 according to the first embodiment will be described. FIG. 1 is a diagram showing an example of use of the radiant heater device 10 according to the first embodiment. As shown in FIG. 1, the radiant heater device 10 is installed in the cabin of an automobile 1, and is a device that applies radiant heat to an occupant. The radiant heater device 10 is disposed on a wall portion facing the occupant in the cabin. Specifically, the installation location of the radiant heater device 10 includes a wall 2 forming the ceiling of the cabin and a wall 3 forming a column cover. Other installation locations in the cabin include a wall forming a pillar, a wall forming an underpanel, a wall forming a door, and a wall forming a foot space. In this embodiment, the radiant heater device 10 is installed in an automobile, but may be installed in other moving bodies such as an airplane, a train, a ship, and a motorcycle. In addition, even if it is not a moving body, it may be installed on furniture such as a desk or a chair, or in a building itself.

[0040] FIG. 2 is a cross-sectional view showing the installation structure of the radiant heater device 10 according to the first embodiment. In FIG. 2, the radiant heater device 10 is not shown in cross section. Here, the radiant heater device 10 is formed in a flat plate shape, one of its main surfaces is a radiant surface 11 that radiates heat, and the other main surface is an adhesive surface 12 that is adhesively fixed to a base member 4. The base member 4 and the radiant heater device 10 are disposed inside the wall 3, and the base member 4 is screwed to a boss 5 that protrudes inward from the wall 3. A plurality of openings 6 for emitting radiant heat are formed in the wall 3. The radiant heater device 10 is disposed so that the radiant surface 11 faces the plurality of openings 6.

[0041] (Radiant heater device) 3 is a cross-sectional view showing a schematic configuration of the radiant heater device 10 according to embodiment 1. In the following figures, the thickness direction of the radiant heater device 10 is defined as the Z-axis direction, and two directions perpendicular to each other in a plane perpendicular to the Z-axis direction are defined as the X-axis direction and the Y-axis direction.

[0042] 3, the radiant heater device 10 includes a heater element 20, a first heat transfer sheet 30, a second heat transfer sheet 40, a heat insulating material 50, and a first radiation sheet 60. The radiation surface 11 of the radiant heater device 10 faces the negative Z-axis direction and emits radiant heat in the negative Z-axis direction. For this reason, in the following description, the positive Z-axis direction may be referred to as the "front" and the negative Z-axis direction as the "rear".

[0043] The heater element 20 is a flexible sheet-like element including a base material 21 and a heater wire 22. The base material 21 is an insulating sheet formed into a rectangular shape when viewed in the Z-axis direction. Specifically, the base material 21 is formed of either a nonwoven fabric or urethane. This can enhance the heat resistance of the base material 21.

[0044] The heater wire 22 is, for example, a cord-shaped heater, and is arranged on the front surface of the substrate 21. Specifically, the heater wire 22 is bonded and fixed to the front surface of the substrate 21 in a state where it is arranged in a pattern that covers the entire front surface of the substrate 21. The heater wire 22 is connected to a power supply unit (not shown), and generates heat when power is supplied from the power supply unit. The heater wire 22 has a metal core wire and an insulating material that covers the core wire. The core wire is formed of, for example, a Cu-Ag alloy or a Cu-Mg alloy. This allows for effective heat generation. Note that the heater element 20 has slight unevenness on one surface due to the heater wire 22 arranged on the substrate 21, but even if the unevenness is included, it can be said that the heater element 20 as a whole is formed in a flat plate shape.

[0045] The first heat transfer sheet 30 is a metal heat transfer sheet that transfers heat from the heater element 20 forward and toward a plane (XY plane) perpendicular to the Z-axis direction. Specifically, the first heat transfer sheet 30 is made of copper. The first heat transfer sheet 30 is laminated on the front surface (first surface) of the heater element 20. The front surface of the heater element 20 and the rear surface of the first heat transfer sheet 30 are bonded together. This bonding includes bonding with an adhesive, bonding with a double-sided tape, welding caused by at least one of the heater element 20 and the first heat transfer sheet 30, and the like. The adhesive layer is not shown in the figure. The first heat transfer sheet 30 is formed to have the same shape as the heater element 20 when viewed in the Z-axis direction.

[0046] The second heat transfer sheet 40 is a metal heat transfer sheet that transfers heat from the heater wire 22 toward a plane (XY plane) perpendicular to the Z-axis direction. The second heat transfer sheet 40 is made of a material having a lower thermal conductivity than the first heat transfer sheet 30. Specifically, the second heat transfer sheet 40 is made of aluminum. The materials of the first heat transfer sheet 30 and the second heat transfer sheet 40 may be any as long as the material of the first heat transfer sheet 30 has a higher thermal conductivity than the material of the second heat transfer sheet 40. The second heat transfer sheet 40 is laminated on the rear surface (second surface) of the heater element 20 opposite the front surface. The rear surface of the heater element 20 and the front surface of the second heat transfer sheet 40 are bonded together. This bonding includes bonding with an adhesive, bonding with a double-sided tape, welding caused by at least one of the heater element 20 and the second heat transfer sheet 40, and the like. The adhesive layer is not shown in the figure. The outer shape of the second heat transfer sheet 40 is the same as that of the first heat transfer sheet 30 .

[0047] The heat insulating material 50 is a member that blocks heat transmitted from the heater element 20 through the second heat transfer sheet 40. In other words, the heat insulating material 50 can prevent heat from the heater element 20 from moving toward the rear side. The heat insulating material 50 may be made of any material that has heat insulating properties. Examples of materials that have heat insulating properties include glass wool, urethane foam, urethane sponge, melamine resin, and polystyrene foam. Therefore, a high heat insulating effect can be achieved. The heat insulating material 50 is laminated on the rear surface of the second heat transfer sheet 40. In other words, the heat insulating material 50 is disposed behind (on the second surface side) the heater element 20. It can also be said that the second heat transfer sheet 40 is interposed between the heat insulating material 50 and the heater element 20.

[0048] The front surface of the heat insulating material 50 and the rear surface of the second heat transfer sheet 40 are bonded together. This bonding includes bonding with an adhesive, bonding with double-sided tape, welding caused by at least one of the heat insulating material 50 and the second heat transfer sheet 40, and the like. The adhesive layer is not shown in the figure. The heat insulating material 50 is formed to have the same shape as the heater element 20 when viewed in the Z-axis direction. From the viewpoint of thermal insulation, it is preferable that the thickness of the heat insulating material 50 is greater than the thickness of the second heat transfer sheet 40.

[0049] The first radiation sheet 60 is a sheet body that generates radiant heat (electromagnetic waves such as infrared rays) by heat transmitted from the heater element 20 via the first heat transfer sheet 30. The first radiation sheet 60 may be in any form as long as it generates radiant heat by heat. Specifically, the first radiation sheet 60 is formed from flame-resistant fibers. More specifically, the first radiation sheet 60 is formed from a nonwoven fabric of flame-resistant fibers obtained by baking and carbonizing special acrylic fibers at 200 to 300°C in air. The nonwoven fabric of flame-resistant fibers may include nonwoven fabrics such as nonwoven fabrics made of polyurethane fibers and heat-resistant spunbond.

[0050] Here, the flame-retardant fiber is a fiber obtained by heat-treating, for example, organic fibers (polyacrylonitrile fibers, rayon, pitch-based fibers, etc.) at about 200 to 350°C in air or an oxidizing atmosphere, and is also called oxidized fiber, infusible fiber, or flame-resistant fiber. Flame-retardant fiber is known as a fiber obtained in the flame-retardant process, which is the first process of producing carbon fiber, and carbon fiber can be obtained by heating this flame-retardant fiber at 1000 to 1500°C in an inert atmosphere. For example, when acrylonitrile fiber is used as a raw material, a transition to a ladder type due to a ring-closing reaction of the nitrile group, a dehydrogenation reaction by oxygen, and an oxygen-added water reaction occur by heat treatment at about 200 to 350°C in air or an oxidizing atmosphere. At this point, carbonization has not yet occurred, and the state is one in which elements such as oxygen, hydrogen, and nitrogen are contained in large amounts, so it cannot be called carbon fiber. Carbon fiber is a harder material because it is carbonized by heating at 1000 to 1500°C in an inert atmosphere. The elastic modulus of the flame-resistant fiber is 100 to 150 g / d, whereas the elastic modulus of the pitch-based carbon fiber is 220 to 300 g / d, making the flame-resistant fiber more flexible. The first radiation sheet 60 may be a woven fabric or knitted fabric instead of a nonwoven fabric, as long as it is made of flame-resistant fiber.

[0051] The emissivity of the first radiating sheet 60 needs only to be 0.6 or more. In this embodiment, a dark colored sheet is used as the first radiating sheet 60. Compared to a white colored sheet, a dark colored sheet has a stronger tendency to emit radiant heat when heat is applied. Also, the darker the color, the higher the emissivity. For this reason, it is preferable that the first radiating sheet 60 is a black sheet. In this embodiment, a black acetate tape is used as the first radiating sheet 60.

[0052] The first radiation sheet 60 has a central portion 61 laminated on the front surface of the first heat transfer sheet 30, and an end portion 62 folded back to be placed on the rear surface of the heat insulating material 50. FIG. 4 and FIG. 5 are plan views showing examples of the arrangement of the end portion 62 of the first radiation sheet 60 according to the first embodiment. In FIG. 4, only both ends 62 of the first radiation sheet 60 in the Y-axis direction are folded back to be placed on the rear surface of the heat insulating material 50. In FIG. 5, both ends 62 of the first radiation sheet 60 in the Y-axis direction and both ends 62 of the first radiation sheet 60 in the X-axis direction are folded back to be placed on the rear surface of the heat insulating material 50. In either case, the end portion 62 is placed inward from the edge of the heater element 20 when the heater element 20 is viewed in plan (in the Z-axis direction). Furthermore, in either case, the central portion of the rear surface of the heat insulating material 50 is exposed from the first radiation sheet 60.

[0053] As shown in FIG. 3, the first radiation sheet 60 has a central portion 61, which is a main portion, disposed in front of the heater element 20 (first surface side). Therefore, the first heat transfer sheet 30 is interposed between the central portion 61 of the first radiation sheet 60 and the heater element 20. Of the end portion 62 of the first radiation sheet 60, a portion overlapping the rear surface of the heat insulating material 50 is a first overlapping portion 63, and a portion overlapping each of the side surfaces of the heater element 20, the first heat transfer sheet 30, the second heat transfer sheet 40, and the heat insulating material 50 is a second overlapping portion 64. The rear surface of the central portion 61 and the front surface of the first heat transfer sheet 30 are bonded. The front surface of the first overlapping portion 63 and the rear surface of the heat insulating material 50 are bonded. The inner surface of the second overlapping portion 64 and each of the side surfaces of the heater element 20, the first heat transfer sheet 30, the second heat transfer sheet 40, and the heat insulating material 50 are bonded. These bonding methods include bonding with an adhesive, bonding with double-sided tape, welding caused by at least one of the objects to be bonded, and the like. This adhesive layer is not shown in the drawings.

[0054] (effect) As described above, according to the radiant heater device 10 of the present disclosure, since the first heat transfer sheet 30 is interposed between the heater element 20 and the first radiation sheet 60, the heat from the heater wire 22 can be spread in a planar manner by the first heat transfer sheet 30. This makes it possible to reduce the temperature difference between the heater wire 22 and the area of ​​the base material 21 where the heater wire 22 is not arranged, enabling even heat generation. Therefore, the amount of radiant heat can be increased.

[0055] Furthermore, the first heat transfer sheet 30 can uniformly heat the inside of the radiant heater device 10, and the heat resistance requirements for members such as the insulating material 50 can be relaxed.

[0056] Since the second heat transfer sheet 40 is interposed between the heater element 20 and the heat insulating material 50, the heat from the heater wire 22 can be spread in a planar manner even on the second heat transfer sheet 40. This can further reduce the temperature difference between the heater wire 22 and the area of ​​the base material 21 where the heater wire 22 is not arranged, enabling uniform heat generation. Therefore, the heat transferred from the heater wire 22 to the second heat transfer sheet 40 reaches the center part 61 via the double folded part 64 of the first radiation sheet 60, so that the amount of radiation of radiant heat can be further increased. In addition, the second heat transfer sheet 40 can suppress the temperature rise from exceeding the heat resistance temperature of the member by lowering the rear surface temperature of the second heat transfer sheet 40, which has the most severe temperature conditions, while ensuring the amount of radiation of radiant heat.

[0057] FIG. 6 is a table showing the temperature of each part and the amount of radiation of radiant heat in the radiant heater device 10 according to the first embodiment and a radiant heater device which is a comparative example. The comparative examples are different from the radiant heater device 10 of the first embodiment in the presence or absence of the first heat transfer sheet 30 and the second heat transfer sheet 40. Specifically, the comparative example 1 is different from the radiant heater device 10 in that it does not have either the first heat transfer sheet 30 or the second heat transfer sheet 40. The comparative example 2 is different from the radiant heater device 10 in that it does not have only the second heat transfer sheet 40. The comparative example 3 is different from the radiant heater device 10 in that it does not have only the first heat transfer sheet 30. In either case, the temperature of the heater element 20 is the same (for example, a temperature within the range of 120°C to 150°C).

[0058] 6, it can be seen that the amount of radiation heat emitted is increased in all of Comparative Example 2, Comparative Example 3 and Embodiment 1 compared to Comparative Example 1, but is greatest in Embodiment 1. From this point of view, it can be said that it is preferable for the radiant heater device 10 to have both the first heat transfer sheet 30 and the second heat transfer sheet 40.

[0059] Since the thermal conductivity of the material of the first heat transfer sheet 30 is greater than that of the material of the second heat transfer sheet 40, the second heat transfer sheet 40 acts as a thermal barrier, making it easier for heat from the heater element 20 to be transferred to the first heat transfer sheet 30. This makes it possible to further increase the amount of radiant heat emitted.

[0060] At least one end 62 of the first radiation sheet 60 is folded back and disposed inward from the end edge of the heater element 20 when the heater element 20 is viewed in plan, so that the first radiation sheet 60 has a structure in which it embraces the heater element 20. This makes it possible to increase the adhesion area of ​​the first radiation sheet 60, and since the first radiation sheet 60 embraces the heater element 20, it is possible to prevent the first radiation sheet 60 from peeling off and being damaged.

[0061] Since at least one end 62 of the first radiation sheet 60 is disposed overlapping the rear surface of the thermal insulation material 50, the heat from the heater element 20 is blocked by the thermal insulation material 50 and is less likely to reach at least one end 62 of the first radiation sheet 60. Therefore, it is possible to suppress a decrease in adhesive strength at at least one end 62 of the first radiation sheet 60, and it is possible to more reliably suppress peeling of the first radiation sheet 60.

[0062] Since the heater wire 22 is covered with an insulating material, electrical conduction between the heater wire 22 and the first heat-transfer sheet 30 can be prevented, and electrical stability can be achieved.

[0063] In particular, in the case of Figure 5, the end of the first radiation sheet 60 is folded back and positioned on the rear side so that the first radiation sheet 60 surrounds the outer peripheral edge of the heater element 20, so that the first radiation sheet 60 has a structure that embraces the outer peripheral edge of the heater element 20, and peeling of the first radiation sheet 60 can be more reliably suppressed.

[0064] Second Embodiment Next, a description will be given of a radiant heater device 10A according to embodiment 2. In the following description, parts equivalent to those in embodiment 1 or other embodiments will be given the same reference numerals and the description thereof will be omitted in some cases.

[0065] FIG. 7 is a cross-sectional view showing a schematic configuration of the radiant heater device 10A according to the second embodiment. FIG. 7 is a view corresponding to FIG. 3. In the first embodiment, the central part of the rear surface of the heat insulating material 50 is exposed from the first radiation sheet 60. As shown in FIG. 7, the radiant heater device 10A according to the second embodiment includes a second radiation sheet 70 that covers the rear surface of the heat insulating material 50 together with at least one end 62 of the first radiation sheet 60. The second radiation sheet 70 is a sheet body having a heat absorptivity (emissivity) of 0.6 or more. Specifically, the second radiation sheet 70 may be a dark-colored sheet body like the first radiation sheet 60 described above, but a black sheet body is more preferable. The type of the sheet body may be any type, but is preferably paper from the viewpoint of cost. The second radiation sheet 70 may be laminated on at least a part of the part exposed from the first radiation sheet 60 on the rear surface of the heat insulating material 50, but in this embodiment, it is laminated on the entire exposed part. The front surface of the second radiation sheet 70 and the rear surface of the heat insulating material 50 are bonded together. This bonding includes bonding with an adhesive, bonding with double-sided tape, welding caused by at least one of the second radiation sheet 70 and the heat insulating material 50, and the like. This adhesive layer is not shown in the drawings.

[0066] Here, the rear surface (adhesive surface 12) of the radiant heater device 10A is adhered and fixed to the interior (base member 4) of the automobile 1 with double-sided tape. Specifically, the double-sided tape is provided, for example, on the outer periphery of the adhesive surface 12 so as to form a gap between the interior of the automobile 1 and the adhesive surface 12. At this time, if the automobile 1 is in a low-temperature environment (for example, an environment where the outside air temperature is -20 degrees or lower), the adhesive strength of the double-sided tape may decrease. In this embodiment, since the rear surface of the heat insulating material 50 is covered with at least one end 62 of the first radiation sheet 60 and the second radiation sheet 70, the end 62 and the second radiation sheet 70 absorb and radiate a small amount of heat transferred through the heat insulating material 50. This radiation can suppress the decrease in adhesive strength of the double-sided tape caused by low temperature.

[0067] Third embodiment Next, the radiant heater device 10B according to the third embodiment will be described. FIG. 8 is a cross-sectional view showing a schematic configuration of the radiant heater device 10B according to the third embodiment. FIG. 8 is a view corresponding to FIG. 3. In the first embodiment, the central part of the rear surface of the heat insulating material 50 is exposed from the first radiant sheet 60. As shown in FIG. 8, in the radiant heater device 10B according to the third embodiment, at least one end 62b of the first radiant sheet 60b covers the entire rear surface of the heat insulating material 50. Specifically, both ends 62b in the X-axis direction of the first radiant sheet 60 extend to the central part of the heat insulating material 50 in the Y-axis direction, and the tips of the ends 62b are adjacent to each other. The adjacent positions may be other positions. Even with such a configuration, the adhesion area of ​​the first radiant sheet 60c can be increased, so that the first radiant sheet 60c can be more reliably prevented from peeling off and being damaged.

[0068] In this way, at least one end 62b of the first radiation sheet 60b covers the entire rear surface of the heat insulating material 50, so that the adhesion area of ​​the first radiation sheet 60b can be increased. Therefore, it is possible to more reliably prevent the first radiation sheet 60b from peeling off and being damaged. Furthermore, since the entire rear surface of the heat insulating material 50 is covered with at least one end 62b of the first radiation sheet 60b, the end 62b absorbs and radiates a small amount of heat transmitted through the heat insulating material 50. This radiation can prevent a decrease in adhesion to the interior caused by low temperatures.

[0069] Fourth embodiment Next, a radiant heater device 10C according to the fourth embodiment will be described. FIG. 9 is a cross-sectional view showing a schematic configuration of the radiant heater device 10C according to the fourth embodiment. FIG. 9 is a view corresponding to FIG. 3. In the first embodiment, a case where a plurality of ends 62 in the first radiant sheet 60 are folded back is illustrated. As shown in FIG. 9, in the radiant heater device 10C according to the fourth embodiment, only one end 62c of the first radiant sheet 60c is folded back. Specifically, the one end 62c of the first radiant sheet 60c covers the entire rear surface of the heat insulating material 50. The end 62c may cover only a part of the rear surface of the heat insulating material 50.

[0070] Fifth embodiment Next, a radiant heater device 10D according to the fifth embodiment will be described. FIG. 10 is a cross-sectional view showing a schematic configuration of the radiant heater device 10D according to the fifth embodiment. FIG. 10 is a view corresponding to FIG. 3. In the radiant heater device 10 according to the first embodiment, at least one end 62 of the first radiant sheet 60 is arranged overlapping the rear surface of the heat insulating material 50. As shown in FIG. 10, in the radiant heater device 10D according to the fifth embodiment, at least one end 62d of the first radiant sheet 60d is interposed between the heater element 20 and the heat insulating material 50. Specifically, the first overlapping portion 63d of the end 62d of the first radiant sheet 60d is interposed between the heat insulating material 50 and the second heat transfer sheet 40 and is bonded thereto. The second overlapping portion 64d is overlapped on the side surfaces of the heater element 20, the first heat transfer sheet 30, and the second heat transfer sheet 40 and is bonded thereto.

[0071] In this manner, at least one end 62d of the first radiation sheet 60d is interposed between the heater element 20 and the second heat transfer sheet 40, and the thermal insulation material 50, and therefore the end 62d is sandwiched between the heater element 20 and the second heat transfer sheet 40, and the thermal insulation material 50. This makes the at least one end 62d of the first radiation sheet 60d less likely to peel off and less likely to be damaged.

[0072] Sixth Embodiment Next, a radiant heater device 10E according to the sixth embodiment will be described. FIG. 11 is a cross-sectional view showing a schematic configuration of the radiant heater device 10E according to the sixth embodiment. FIG. 11 is a view corresponding to FIG. 3. In the first embodiment, the case where the radiant heater device 10 includes the second heat transfer sheet 40 is illustrated. As shown in FIG. 11, in the radiant heater device 10E according to the sixth embodiment, the second heat transfer sheet is not provided, and the heat insulating material 50 is directly adhered to the heater element 20. The sixth embodiment corresponds to the comparative example 2 in FIG. 6. Even in this case, the first heat transfer sheet 30 can spread the heat from the heater wire 22 in a planar shape. This can reduce the temperature difference between the heater wire 22 and the region of the base material 21 where the heater wire 22 is not arranged, and uniform heat generation is possible. Therefore, the amount of radiation of radiant heat can be increased. Furthermore, at least one end 62 of the first radiation sheet 60 is folded back and disposed inward from the end edge of the heater element 20 when the heater element 20 is viewed in plan, so that the first radiation sheet 60 has a structure in which it embraces the heater element 20. This makes it possible to increase the adhesion area of ​​the first radiation sheet 60, and since the first radiation sheet 60 embraces the heater element 20, it is possible to prevent the first radiation sheet 60 from peeling off and being damaged.

[0073] Seventh embodiment Next, the radiant heater device 10F according to the seventh embodiment will be described. FIG. 12 is a cross-sectional view showing a schematic configuration of the radiant heater device 10F according to the seventh embodiment. FIG. 12 is a view corresponding to FIG. 11. In the sixth embodiment, the case where the radiant heater device 10E includes the first heat transfer sheet 30 is illustrated. As shown in FIG. 12, in the radiant heater device 10F according to the seventh embodiment, the first heat transfer sheet and the second heat transfer sheet are not provided, and the heater element 20 is directly bonded to the heat insulating material 50 and the first radiation sheet 60. The seventh embodiment corresponds to the comparative example 1 in FIG. 6. Even in this case, at least one end 62 of the first radiation sheet 60 is folded back and is disposed inward from the edge of the heater element 20 when the heater element 20 is viewed in plan, so that the first radiation sheet 60 has a structure in which the heater element 20 is embraced by the first radiation sheet 60. This makes it possible to increase the adhesion area of ​​the first radiation sheet 60, and since the first radiation sheet 60 embraces the heater element 20, it is possible to suppress the first radiation sheet 60 from peeling off and being damaged.

[0074] Eighth Embodiment Next, a radiant heater device 10G according to the eighth embodiment will be described. FIG. 13 is a cross-sectional view showing a schematic configuration of the radiant heater device 10G according to the eighth embodiment. FIG. 13 is a view corresponding to FIG. 11. In the sixth embodiment, a case where at least one end 62 of the first radiant sheet 60 is folded back is illustrated. As shown in FIG. 13, the radiant heater device 10G according to the eighth embodiment has a first radiant sheet 60g that is flat as a whole. Even in this case, the first heat transfer sheet 30 can spread the heat from the heater wire 22 in a planar shape. This can reduce the temperature difference between the heater wire 22 and the region of the base material 21 where the heater wire 22 is not arranged, enabling uniform heat generation. Therefore, the amount of radiation of radiant heat can be increased.

[0075] Ninth Embodiment Next, the radiant heater device 10H according to the ninth embodiment will be described. FIG. 14 is a cross-sectional view showing an enlarged portion of the radiant heater device 10H according to the ninth embodiment. Here, if the diameter of the heater wire 22h is D, the thickness of the first radiation sheet 60h is Tf, and the thickness of the first heat transfer sheet 30h is Tc, then as shown in FIG. 14, the relationship is D>Tc>Tf. As described above, since the thickness Tc of the first heat transfer sheet 30h is smaller than the diameter D of the heater wire 22h, the first heat transfer sheet 30h can be arranged so as to wrap around the heater wire 22h. Therefore, the gap S1 around the heater wire 22h can be suppressed, and the heat of the heater wire 22h can be efficiently transferred to the first heat transfer sheet 30h. Furthermore, since the thickness Tf of the first radiation sheet 60h is smaller than the thickness Tc of the first heat transfer sheet 30h, the first radiation sheet 60h can be laminated along the unevenness of the first heat transfer sheet 30h. This can reduce the gap between the first heat transfer sheet 30h and the first radiation sheet 60h, and can also improve the efficiency of heat transfer from the first heat transfer sheet 30h to the first radiation sheet 60h. As a result, the overall amount of radiated heat can be increased.

[0076] Tenth Embodiment Next, the radiant heater device 10I according to the tenth embodiment will be described. FIG. 15 is a cross-sectional view showing an enlarged portion of the radiant heater device 10I according to the tenth embodiment. Here, if the diameter of the heater wire 22i is D, the thickness of the first radiation sheet 60i is Tf, and the thickness of the first heat transfer sheet 30i is Tc, then as shown in FIG. 15, the relationship is Tf>D>Tc. As described above, since the thickness Tc of the first heat transfer sheet 30i is smaller than the diameter D of the heater wire 22i, the first heat transfer sheet 30i can be disposed so as to wrap around the heater wire 22i. Therefore, the gap S2 around the heater wire 22i can be suppressed, and the heat of the heater wire 22i can be efficiently transferred to the first heat transfer sheet 30i. Furthermore, since the thickness Tf of the first radiation sheet 60i is larger than the diameter D of the heater wire 22i, the first radiation sheet 60i is less likely to deform along the outer shape of the heater wire 22i. For this reason, a gap S3 is likely to be formed between the first heat transfer sheet 30i and the first radiation sheet 60i around the heater wire 22i. This gap S3 reduces the amount of heat transferred from the heater wire 22i, making it possible to prevent a decrease in the adhesive strength between the first radiation sheet 60i and the first heat transfer sheet 30i. Furthermore, the heat capacity of the first radiation sheet 60i makes it difficult for the temperature to rise, and the adhesive strength can be maintained. These factors can increase the reliability of the radiant heater device 10I.

[0077] Eleventh Embodiment Next, the radiant heater device 10J according to the eleventh embodiment will be described. FIG. 16 is a cross-sectional view showing an enlarged portion of the radiant heater device 10j according to the eleventh embodiment. Here, if the diameter of the heater wire 22j is D, the thickness of the first radiation sheet 60j is Tf, and the thickness of the first heat transfer sheet 30j is Tc, then as shown in FIG. 16, the relationship is Tc>D>Tf. As described above, since the thickness Tc of the first heat transfer sheet 30j is larger than the diameter D of the heater wire 22j, the first heat transfer sheet 30j is less likely to deform along the outer shape of the heater wire 22j. For this reason, a gap S4 can be formed around the heater wire 22. Due to the insulating effect of this gap S4, unnecessary heat loss can be suppressed, and efficiency can be improved. The gap S4 reduces the adhesive area between the heater wire 22j and the first heat transfer sheet 30j, but even if localized heat transfer occurs, the thickness Tc of the first heat transfer sheet 30j is larger than the diameter D of the heater wire 22j, so the first heat transfer sheet 30j can achieve uniform heat transfer. The gap S4 around the heater wire 22j suppresses the amount of heat transfer from the heater wire 22j, so it is possible to suppress a decrease in adhesive strength between the first radiation sheet 60j and the first heat transfer sheet 30j. In addition, the heat capacity of the first heat transfer sheet 30j makes it difficult for the temperature to rise, so that the adhesive strength can be maintained and reliability can be improved. Furthermore, the thickness Tf of the first radiation sheet 60j is smaller than the thickness Tc of the first heat transfer sheet 30j, so the first radiation sheet 60j can be laminated along the unevenness of the first heat transfer sheet 30j. This makes it possible to reduce the gap between the first heat transfer sheet 30j and the first radiation sheet 60j, and also makes it possible to efficiently transfer heat from the first heat transfer sheet 30j to the first radiation sheet 60j.

[0078] [others] Although the radiant heater device according to the present disclosure has been described above based on the embodiment, the present disclosure is not limited to this embodiment. As long as it does not deviate from the spirit of the present disclosure, various modifications conceivable by a person skilled in the art to the embodiment and forms constructed by combining components of different embodiments may also be included within the scope of one or more aspects of the present disclosure.

[0079] In the above embodiment, the first radiation sheet 60 is made of flame-resistant fiber. However, the first radiation sheet may be made of a material other than flame-resistant fiber.

[0080] In the above embodiment, the thermal conductivity of the material of the first heat transfer sheet 30 is greater than the thermal conductivity of the material of the second heat transfer sheet 40. However, the first heat transfer sheet and the second heat transfer sheet may be made of the same material. For example, the first heat transfer sheet and the second heat transfer sheet may be made of aluminum. Since the first heat transfer sheet and the second heat transfer sheet are made of the same material, the linear expansion coefficient of the first heat transfer sheet and the linear expansion coefficient of the second heat transfer sheet can be made equal. This allows the first heat transfer sheet and the second heat transfer sheet to expand (deform) equally when they are heated by a heater element. For example, if the first heat transfer sheet and the second heat transfer sheet have different amounts of deformation, the heater element sandwiched between them may be damaged. However, if the amounts of deformation of the first heat transfer sheet and the second heat transfer sheet are equal, damage to the heater element can be suppressed.

[0081] [Note] The above description of the embodiments and the like discloses the following techniques.

[0082] (Technology 1) a heater element having a sheet-like substrate and a heater wire disposed on the substrate; A first radiation sheet arranged on a first surface side of the heater element and made of flame-resistant fiber; a heat transfer sheet interposed between the heater element and the first radiation sheet; Radiant heater device.

[0083] (Technology 2) When the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, D>Tc. The radiant heater device according to claim 1.

[0084] (Technology 3) When the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, Tc>D. The radiant heater device according to claim 1.

[0085] (Technology 4) When the thickness of the first radiation sheet is Tf and the thickness of the heat transfer sheet is Tc, Tc>Tf. The radiant heater device according to claim 1.

[0086] (Technology 5) When the diameter of the heater wire is D, the thickness of the first radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, D>Tc>Tf. The radiant heater device according to claim 1.

[0087] (Technology 6) When the diameter of the heater wire is D, the thickness of the first radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, Tf>D>Tc. The radiant heater device according to claim 1.

[0088] (Technology 7) When the diameter of the heater wire is D, the thickness of the first radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, Tc>D>Tf. The radiant heater device according to claim 1.

[0089] (Technology 8) a heat insulating material disposed on a second surface side of the heater element opposite to the first surface; The radiant heater device according to any one of the first to seventh aspects.

[0090] (Technology 9) The heat insulating material is formed from any one of glass wool, urethane foam, urethane sponge, melamine resin, and polystyrene foam. 9. The radiant heater device according to claim 8.

[0091] (Technology 10) The heater wire is covered with an insulating material. The radiant heater device according to any one of the first to ninth aspects.

[0092] (Technology 11) The heater wire is made of either a Cu-Ag based alloy or a Cu-Mg based alloy. The radiant heater device according to claim 10.

[0093] (Technology 12) The substrate is made of one of a nonwoven fabric and a urethane. The radiant heater device according to any one of the first to eleventh aspects of the present invention.

[0094] (Technology 13) The emissivity of the radiation sheet is 0.6 or more. 13. The radiant heater device according to claim 1.

[0095] (Technology 14) The heat transfer sheet is adhered to the heater element and the radiation sheet. The radiant heater device according to any one of the first to thirteenth aspects. [Industrial Applicability]

[0096] The present disclosure is applicable to a radiant heater device that emits radiant heat. [Explanation of symbols]

[0097] 1. Automobiles 2. Wall 3. Wall 4 Base material 5. Boss 6 aperture 10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I, 10J Radiant heater device 11 Radiation surface 12 Adhesive surface 20 Heater element 21 Base material 22, 22h, 22i, 22j heater wire 30, 30h, 30i, 30j First heat transfer sheet 40 Second heat transfer sheet 50 Insulation 60, 60b, 60c, 60d, 60g, 60h, 60i, 60j First radiation sheet (radiation sheet) 61 Central part 62, 62b, 62c, 62d ends 63, 63d First overlapping part 64, 64d Double-folding section 70 Second radiation sheet D diameter Tc, Tf thickness S1, S2, S3, S4 gap

Claims

1. a heater element having a sheet-like substrate and a heater wire disposed on the substrate; A radiation sheet made of flame-resistant fiber and arranged on a first surface side of the heater element; a heat transfer sheet interposed between the heater element and the radiation sheet; Radiant heater device.

2. When the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, D>Tc. The radiant heater device of claim 1 .

3. When the diameter of the heater wire is D and the thickness of the heat transfer sheet is Tc, Tc>D. The radiant heater device of claim 1 .

4. When the thickness of the radiation sheet is Tf and the thickness of the heat transfer sheet is Tc, Tc>Tf. The radiant heater device of claim 1 .

5. When the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, D>Tc>Tf. The radiant heater device of claim 1 .

6. When the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, Tf>D>Tc. The radiant heater device of claim 1 .

7. When the diameter of the heater wire is D, the thickness of the radiation sheet is Tf, and the thickness of the heat transfer sheet is Tc, Tc>D>Tf. The radiant heater device of claim 1 .

8. a heat insulating material disposed on a second surface side of the heater element opposite to the first surface; The radiant heater device according to any one of claims 2 to 7.

9. The heat insulating material is formed from any one of glass wool, urethane foam, urethane sponge, melamine resin, and polystyrene foam. The radiant heater device of claim 8.

10. The heater wire is covered with an insulating material. The radiant heater device according to any one of claims 2 to 7.

11. The heater wire is made of either a Cu-Ag based alloy or a Cu-Mg based alloy. The radiant heater device of claim 10.

12. The substrate is made of one of a nonwoven fabric and a urethane. The radiant heater device according to any one of claims 2 to 7.

13. The emissivity of the radiation sheet is 0.6 or more. The radiant heater device according to any one of claims 2 to 7.

14. The heat transfer sheet is adhered to the heater element and the radiation sheet. The radiant heater device according to any one of claims 2 to 7.

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