Heater and heater unit

Abstract

A heater 2A comprises multiple heater cells 7 disposed on the same surface. The heater cells 7 each include: a first switch part 6 through which current flows when pressure is applied; and a heat-generating part 417A that is connected in-series to the first switch part 6 and generates heat due to electrical resistance.

Description

Heater and heater unit

[0001] The present invention relates to a heater and a heater unit comprising the same heater. In designated countries where incorporation by reference is permitted, the contents described in Japanese Patent Application No. 2025-47084, filed in Japan on March 21, 2025, are incorporated herein by reference and constitute part of this specification.

[0002] A heater operation control device is known that includes a heater and a human body position detection means for detecting the position of a human body based on electric potential (see, for example, Patent Document 1). This operation control device controls the power supplied to the heater according to the position of the human body detected by the human body position detection means.

[0003] Japanese Patent Publication No. 2021-44174

[0004] In the above-mentioned Patent Document 1, a microcontroller, power control circuit, multiple relays, and multiple resistors must be provided separately from the heater for detecting the position of the human body and controlling the heater based on the position detection results. This leads to the problem that the operation control device becomes large.

[0005] The problem that this invention aims to solve is to provide a heater and a heater unit that can be miniaturized.

[0006] [1] One aspect of the present invention is a heater comprising a plurality of heater cells arranged on the same plane, each of which includes a first switch section that conducts current when pressure is applied, and a heating section connected in series with the first switch section and generating heat due to electrical resistance.

[0007] [2] A second aspect of the present invention is the heater of aspect 1, wherein the heater further comprises a first lead wiring and a second lead wiring separated from the first lead wiring, and the plurality of heater cells may be heaters connected in parallel to the first and second lead wiring.

[0008] [3] A third aspect of the present invention is a heater according to aspect 1 or 2, wherein the heater further comprises a first substrate, a second substrate facing the first substrate, and a spacer having an opening and interposed between the first substrate and the second substrate, the heating portion being provided on the first substrate or the second substrate, and the first switch portion including a first electrode provided on the first substrate and a second electrode provided on the second substrate so as to face the first electrode through the opening.

[0009] [4] Embodiment 4 of the present invention is the heater of Embodiment 3, wherein the heating element is provided on the second substrate and connected in series with the second electrode.

[0010] [5] Embodiment 5 of the present invention is a heater in which, in any one of embodiments 1 to 4, the electrical resistance value of the heating element is higher than the electrical resistance value of the first switch element.

[0011] [6] Embodiment 6 of the present invention is a heater in any one of embodiments 1 to 5 in which the heating element includes a fine wire having a cross-sectional area smaller than the cross-sectional area of ​​the first switch element.

[0012] [7] Embodiment 7 of the present invention is a heater according to Embodiment 6, wherein the thin wire is a heater that extends so as to surround the first switch portion.

[0013] [8] Embodiment 8 of the present invention is a heater in any one of embodiments 1 to 7 in which the electrical resistivity of the first material constituting the heating portion is greater than the electrical resistivity of the second material constituting the first switch portion.

[0014] [9] Aspect 9 of the present invention is a heater in any one of aspects 1 to 8, wherein the heating portion includes a first portion connected in series with the first switch portion and a second portion connected in series with the first switch portion and separated from the first portion, and the first portion and the second portion are arranged symmetrically with respect to the first switch portion.

[0015]

[10] Embodiment 10 of the present invention is a heater according to Embodiment 9, wherein the heater further comprises a first substrate, a second substrate facing the first substrate, a spacer having an opening and interposed between the first substrate and the second substrate, a first lead wiring provided on the first substrate, and a second lead wiring provided on the second substrate, wherein the heating portion is provided on the first substrate or the second substrate, and the first switch portion comprises a first electrode provided on the first substrate and a second switch provided on the second substrate so as to face the first electrode through the opening. A heater may include a second electrode, the second lead wiring comprising a third lead wiring provided on the second substrate so as to be spaced adjacent to the first electrode, and a fourth lead wiring provided on the second substrate so as to be positioned on the opposite side of the second electrode from the third lead wiring, wherein the first portion is interposed between the third lead wiring and the second electrode, the second portion is interposed between the fourth lead wiring and the second electrode, and the first and second portions are arranged symmetrically with respect to the second electrode.

[0016]

[11] Embodiment 11 of the present invention is a heater in any one of embodiments 1 to 10, wherein the heater further comprises a plurality of load transmission members arranged at positions corresponding to a plurality of first switch portions, and each of the load transmission members transmits the load to the plurality of first switch portions when pressed by a load from outside the heater.

[0017]

[12] Aspect 12 of the present invention is a heater according to aspect 11, wherein the heater further comprises a first substrate, a second substrate facing the first substrate, and a spacer having an opening and interposed between the first substrate and the second substrate, the heating portion is provided on the first substrate or the second substrate, the first switch portion includes a first electrode provided on the first substrate and a second electrode provided on the second substrate so as to face the first electrode through the opening, and the plurality of load transmission members may be heaters arranged on the first or second substrate so as to correspond to the plurality of first switch portions.

[0018]

[13] Embodiment 13 of the present invention is a heater according to embodiment 12 in which the width of the load transmission member is smaller than the width of the opening.

[0019]

[14] Embodiment 14 of the present invention is a heater unit comprising one heater from embodiments 1 to 13 and a heater control circuit that supplies current to the heater cell to heat the heating element.

[0020]

[15] Embodiment 15 of the present invention is a heater cell according to embodiment 14, wherein the heater further comprises a first substrate, a second substrate facing the first substrate, and a spacer having an opening and interposed between the first substrate and the second substrate, the first switch unit includes a first electrode provided on the first substrate and a second electrode provided on the second substrate so as to face the first electrode through the opening, the heating unit is provided on the second substrate and connected in series with the second electrode, and the heater unit may be a heater unit comprising a second switch unit interposed between the heater control circuit and the first switch unit, and which switches the electrical connection destination of the heater control circuit to the first electrode or the second electrode.

[0021] In this invention, each heater cell is equipped with a first switch that conducts current when pressure is applied, and a heating element connected in series with this first switch, thereby enabling miniaturization of the heater unit.

[0022] Figure 1 is a plan view showing a heater unit in an embodiment of the present invention. Figures 2(a) and 2(b) are cross-sectional views showing a cross section along the line II-II in Figure 1, where Figure 2(a) shows the state where no pressure is applied to the first switch section, and Figure 2(b) shows the state where pressure is applied to the first switch section. Figure 3 is a bottom view showing the upper electrode sheet in an embodiment of the present invention. Figure 4 is a plan view showing the lower electrode sheet in an embodiment of the present invention. Figure 5(a) is a plan view showing a first modified example of the heating section in an embodiment of the present invention, and Figure 5(b) is a plan view showing a second modified example of the heating section in an embodiment of the present invention. Figure 6 is a cross-sectional view showing a first modified example of the heater unit in an embodiment of the present invention. Figure 7(a) is a cross-sectional view showing a first modified example of the heater in an embodiment of the present invention, and Figure 7(b) is a cross-sectional view showing a second modified example of the heater in an embodiment of the present invention. Figure 8 is a plan view showing a third modified example of the heater in an embodiment of the present invention. Figures 9(a) and 9(b) are cross-sectional views along the line IX-IX in Figure 8. Figure 9(a) shows the state where no pressure is applied to the first switch section, and Figure 8(b) shows the state where pressure is applied to the first switch section via the load transmission member.

[0023] Embodiments of the present invention will be described below with reference to the drawings.

[0024] Figure 1 is a plan view showing the heater unit 1A in this embodiment. Figures 2(a) and 2(b) are cross-sectional views showing a cross-section along the line II-II in Figure 1. Figure 2(a) shows the state in which no pressure is applied to the first switch section 6, and Figure 2(b) shows the state in which pressure is applied to the first switch section 6. Figure 3 is a bottom view showing the upper electrode sheet 3 in this embodiment. Figure 4 is a plan view showing the lower electrode sheet 4 in this embodiment.

[0025] The heater unit 1A is used to warm the human body, animals, plants, objects, etc. As shown in Figure 1, this heater unit 1A comprises a heater 2A and a heater control circuit 8.

[0026] The heater 2A in this embodiment is not particularly limited, but it has a flat sheet shape. A person, animal or plant, or other object to be heated is placed on the heater 2A, and the object to be heated is heated by the heater 2A.

[0027] As shown in Figure 2(a), the heater 2A comprises an upper electrode sheet 3, a lower electrode sheet 4, and a spacer 5. The upper electrode sheet 3 comprises a first base material 30 and a first conductor circuit 31. The lower electrode sheet 4 comprises a second base material 40 and a second conductor circuit 41. The spacer 5 comprises a third base material 50, an upper bonding layer 51, and a lower bonding layer 52.

[0028] In this heater 2A, the upper electrode sheet 3 is bonded to the lower electrode sheet 4 via a spacer 5. Specifically, the upper bonding layer 51 of the spacer 5 is bonded to the lower surface 301 of the first base material 30 of the upper electrode sheet 3, and the lower bonding layer 52 of the spacer 5 is bonded to the upper surface 401 of the second base material 40 of the lower electrode sheet 4. The spacer 5 also has an opening 53, through which the upper and lower electrodes 314, 414 (described later) face each other.

[0029] As shown in Figure 2(b), in this heater 2A, when pressure P from the object to be heated is applied to the upper electrode sheet 3, the upper and lower electrodes 314, 414 (described later) come into contact with each other, and the electrodes 314, 414 become electrically conductive. The upper and lower electrodes 314, 414 are electrically connected to the heater control circuit 8. Therefore, when the upper and lower electrodes 314, 414 become conductive, the power supplied from the heater control circuit 8 is supplied to the heating element 417A (described later). As a result, the heating element 417A generates heat, and the object to be heated is warmed. In other words, the upper and lower electrodes 314, 414 constitute a first switch element 6, and this first switch element 6 functions as an on / off switch that allows current to flow when pressure P is applied.

[0030] As shown in Figure 1, the heater 2A in this embodiment is provided with a plurality of heater cells 7, each consisting of a first switch unit 6 and a heating unit 417A supplied with power via the first switch unit 6. In this embodiment, a plurality of heater cells 7 (12 in this example) are arranged in a matrix on the same plane (on the upper surface 401 of the second base material 40 (see Figure 2(a))). As a result, the first switch unit 6 is energized only in the portion to which pressure P is applied in the heater 2A, and the heating unit 417A connected in series with the energized first switch unit 6 generates heat, thus selectively heating the portion to which pressure P is applied.

[0031] The first substrate 30 of the upper electrode sheet 3 is made of, for example, a flexible insulating material. Examples of such insulating materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polycarbonate (PC), liquid crystal polymer (LCP), polyetherimide (PEI), polyetheretherketone (PEEK), and resin materials such as aramid.

[0032] As shown in Figure 3, a first conductive circuit 31 is provided on the lower surface 301 of the first substrate 30. This first conductive circuit 31 is, for example, a wiring pattern made of a metal material having good conductivity. The metal material is not particularly limited, but examples include aluminum, copper, nickel, nichrome, silver, gold, etc.

[0033] The first conductor circuit 31 is formed on the first substrate 30 using a subtractive method, a fully additive method, or a semi-additive method, although this method is not particularly limited. Alternatively, the first conductor circuit 31 may be formed using a physical vapor deposition (PVD) method such as vacuum deposition or sputtering, or a chemical vapor deposition (CVD) method.

[0034] Alternatively, the first conductive circuit 31 may be formed by printing a conductive paste onto the first substrate 30 and allowing it to solidify (harden). The conductive paste is composed of conductive particles and a binder resin mixed with water or a solvent and various additives.

[0035] The conductive particles are not particularly limited, but particles of the above-mentioned metal materials and compounds thereof can be used. Specific examples of binder resins include acrylic resins, polyester resins, epoxy resins, vinyl resins, urethane resins, phenol resins, polyimide resins, silicone resins, and fluororesins. Furthermore, examples of solvents contained in the conductive paste include α-terpineol, butyl carbitol acetate, butyl carbitol, 1-decanol, butyl cellosolve, diethylene glycol monoethyl ether acetate, and tetradecane. The binder resin may be omitted from the above conductive paste. Also, a conductive ink may be used instead of the above conductive paste.

[0036] The method for printing the conductive paste is not particularly limited, and examples thereof include screen printing, gravure printing, offset printing, gravure offset printing, and flexographic printing. The heat source for curing the conductive paste is not particularly limited, and examples thereof include an electric heating oven, an infrared oven, a far-infrared furnace (IR), a near-infrared furnace (NIR), and a laser irradiation device, and heat treatment combining these may also be used.

[0037] Furthermore, although not particularly limited, the first conductor circuit 31 may be formed of a non-metallic material. In this case, for example, the first conductor circuit 31 may be formed by printing carbon paste on the first base material 30 and curing the printed paste. Specific examples of conductive particles contained in such carbon paste include carbon-based materials such as graphite, carbon black (furnace black, acetylene black, and Ketjen black), carbon nanotubes, and carbon nanofibers. A carbon ink may be used instead of the above carbon paste.

[0038] Alternatively, the first conductor circuit 31 may be formed of a conductive polymer such as PEDOT / PSS. In this case, the first conductor circuit 31 may be formed by a physical vapor deposition method (PVD) such as vacuum evaporation or sputtering, a chemical vapor deposition method (CVD), or a printing method such as screen printing.

[0039] As shown in FIG. 3, the first conductor circuit 31 includes a power supply wiring 311 and a plurality of (twelve in this example) first electrodes 314. The power supply wiring 311 is a wiring for electrically connecting the plurality of first electrodes 314 and the heater control circuit 8, and is formed integrally with the plurality of first electrodes 314.

[0040] The power supply wiring 311 includes a first main wiring 312 and a plurality of (three in this example) first branch wirings 313. The first main wiring 312 extends along the Y direction on the lower surface 301 of the first base material 30. One end of the first main wiring 312 extends to the edge of the lower surface 301. That is, the first main wiring 312 includes an end portion 312a located at the edge of the lower surface 301. Although not particularly limited, a connection terminal provided in the heater control circuit 8, a terminal of an electric wire interposed between the heater 2A and the heater control circuit 8, or the like is joined to the end portion 312a.

[0041] The plurality of first branch wirings 313 are branched from the first main wiring 312. Each of the first branch wirings 313 extends from the first main wiring 312 toward the -X direction in the figure. The first branch wiring 313 corresponds to an example of the "first lead-out wiring" in the embodiment of the present invention.

[0042] Although not particularly limited, the first branch wiring 313 and the first electrode 314 in the present embodiment share a part of each other. Alternatively, the first electrode 314 may be arranged on the +Y side or -Y side of the first branch wiring 313 so as to branch from the first branch wiring 313, and connected to the first branch wiring 313 from the +Y side or -Y side.

[0043] In this embodiment, four first electrodes 314 are connected in parallel to each first branch wiring 313. The multiple first electrodes 314 in this embodiment are not particularly limited, but are arranged in a 3x4 matrix.

[0044] As shown in Figures 1 and 2(a), the planar shape of the first electrode 314 is circular. However, the planar shape of the first electrode 314 is not limited to the above. For example, the planar shape of the first electrode 314 may be rectangular, mesh-like, or comb-like. Also, the diameter of the first electrode 314 may be smaller than the opening 53 (described later) of the spacer 5, or larger than the diameter of the opening 53.

[0045] The second base material 40 of the lower electrode sheet 4 is made of the same material as the first base material 30. However, the material constituting the second base material 40 may be a different insulating material than the material constituting the first base material 30.

[0046] As shown in Figure 4, a second conductive circuit 41 is provided on the upper surface 401 of the second substrate 40. In this embodiment, the second conductive circuit 41 is a wiring pattern made of the same material as the first conductive circuit 31. However, the material constituting the second conductive circuit 41 may be a different conductive material from the material constituting the first conductive circuit 31.

[0047] The second conductor circuit 41 includes a ground wire 411, a plurality (12 in this example) of second electrodes 414, and a plurality (12 in this example) of heating elements 417A.

[0048] In this embodiment, the ground wiring 411 is connected to the ground. This ground wiring 411 comprises a second main wiring 412 and a plurality (three in this example) of second branch wirings 413. The second main wiring 412 extends along the Y direction on the upper surface 401 of the second base material 40.

[0049] As shown in Figure 1, the second main wiring 412 is positioned on the opposite side of the first main wiring 312 from the multiple heater cells 7 in a transparent plan view (a plan view when the heater 2A is viewed through from above or below (in the direction normal to the main surface of the heater 2A)). In other words, the first and second main wirings 312 and 412 are positioned so as to sandwich the multiple heater cells 7 from both sides in a transparent plan view.

[0050] As shown in Figure 4, one end of the second main wiring 412 extends to the edge of the upper surface 401, although this is not particularly limited. The second main wiring 412 has an end 412a. Although this is not particularly limited, this end 412a is connected to the ground 200. Therefore, the current that passes through the heating element 417A flows to the ground 200 via the ground wiring 411.

[0051] Multiple second branch wirings 413 branch off from the second main wiring 412. In this embodiment, each second branch wiring 413 extends from the second main wiring 412 in the +X direction in the figure and is provided on the second base material 40 adjacent to the second electrode 414 with a gap between them. This second branch wiring 413 corresponds to an example of a "second lead wiring" in an embodiment of the present invention.

[0052] As shown in Figure 1, the second branch wiring 413 extends substantially parallel to the first branch wiring 313 in a transparent plan view. Furthermore, the multiple second branch wirings 413 and the multiple first branch wirings 313 do not overlap in a transparent plan view, but are arranged alternately along the Y direction in the figure.

[0053] As shown in Figures 2(a) and 2(b), the second electrode 414 is positioned on the upper surface 401 so as to face the first electrode 314 through the opening 53 of the spacer 5. In other words, the second electrode 414 is positioned so as to be able to contact the first electrode 314 when the first electrode 314 is pressed in the -Z direction by pressure P.

[0054] As shown in Figure 4, the plurality of second electrodes 414 in this embodiment are arranged in a matrix so as to face the first electrode 314. Each second electrode 414 includes a contact portion 415 and an intervening portion 416a.

[0055] The contact portion 415 faces the first electrode 314 through the opening 53. This contact portion 415 is the part that contacts the first electrode 314 and is electrically connected to the first electrode 314 when the first electrode 314 is pressed in the -Z direction by pressure P. The planar shape of the contact portion 415 in this embodiment is circular, similar to that of the first electrode 314, but is not limited to this. For example, the planar shape of the contact portion 415 may be rectangular, mesh-like, or comb-like. Furthermore, it is preferable that the planar shape of the contact portion 415 corresponds to the planar shape of the first electrode 314.

[0056] An intervening portion 416a is connected to the contact portion 415. The intervening portion 416a is integrally formed with the contact portion 415. The intervening portion 416a has a rectangular shape that is narrower than the contact portion 415. The thin wire 418a (described later) of the heating portion 417A is connected to the intervening portion 416a, and by being interposed between the contact portion 415 and the thin wire 418a, the two are electrically connected. The width of the intervening portion 416a is greater than the width of the thin wire 418a. Therefore, compared to the case where the thin wire 418a is directly connected to the contact portion 415, disconnection is less likely to occur at the connection between the thin wire 418a and the second electrode 414, and the reliability of the connection between the second electrode 414 and the thin wire 418a can be improved.

[0057] A heating element 417A is connected in series to the second electrode 414. In this embodiment, the heating element 417A is composed of a single thin wire 418a. As shown in Figure 2(a), the thin wire 418a has a cross-sectional area smaller than the cross-sectional area of ​​the contact portion 415 of the second electrode 414. The cross-sectional area of ​​this thin wire 418a is set to a size that allows the thin wire 418a to generate resistive heat.

[0058] As shown in Figure 4, the thin wire 418a in this embodiment is a spiral-shaped wiring pattern centered on the second electrode 414 and extends to surround the second electrode 414. Because the thin wire 418a extends to surround the second electrode 414 in this way, the heating element 417A is uniformly arranged around the second electrode 414, thereby making the heat distribution around the second electrode 414 uniform.

[0059] The heat-generating section 417A in this embodiment is not limited to the above. The heat-generating section 417A may have any structure as long as it is capable of generating heat through electrical resistance. An example of another structure of the heat-generating section 417A will be described with reference to Figures 5(a) and 5(b).

[0060] Figure 5(a) is a plan view showing a first modified example of the heating element 417A in this embodiment. In this modified example, the heating element 417B has a pair of high-resistance elements 419a and 419b made of a high-resistance material. In this embodiment, the high-resistance elements 419a and 419b are made of a rectangular planar pattern (solid pattern). In addition, to match the shape of these high-resistance elements 419a and 419b, the intervening element 416b of the second electrode 414 in this modified example has a T-shape. This intervening element 416b has a wide portion 420 that is wider than the high-resistance elements 419a and 419b. Because this wide portion 420 is connected to the high-resistance elements 419a and 419b, the current distribution in the high-resistance elements 419a and 419b is reduced and the heat distribution in the high-resistance elements 419a and 419b is made uniform.

[0061] Furthermore, the high-resistance portion 419a and the high-resistance portion 419b are arranged symmetrically with respect to the second electrode 414. Specifically, the high-resistance portion 419a and the high-resistance portion 419b are arranged point-symmetrically with respect to the center of the second electrode 414, and also line-symmetrically with respect to the center line of the second electrode 414 in the X direction. By arranging the high-resistance portion 419a and the high-resistance portion 419b symmetrically with respect to the second electrode 414 in this way, the heat distribution around the second electrode 414 can be made uniform.

[0062] The high-resistance section 419a is connected to the branch wiring 413a. On the other hand, the high-resistance section 419b is connected to the branch wiring 413b, which is located on the opposite side of the second electrode 414 from the branch wiring 413a. In other words, in this modified example, the heating section 417B is connected to a pair of branch wirings 413a and 413b. Although not specifically shown, this pair of branch wirings 413a and 413b are branched from the second main wiring 412 described above and are connected in parallel to the second main wiring 4122. Branch wiring 413a corresponds to an example of the "third lead wiring" in the embodiment of the present invention, and branch wiring 413b corresponds to an example of the "fourth lead wiring" in the embodiment of the present invention. Furthermore, the high-resistance section 419a corresponds to an example of the "first part" in the embodiment of the present invention, and the high-resistance section 419b corresponds to an example of the "second part" in the embodiment of the present invention.

[0063] The electrical resistivity of the materials constituting these high-resistivity sections 419a and 419b is greater than that of the materials constituting the first and second electrodes 314 and 414. Therefore, the electrical resistance of the heating section 417B is higher than that of the first and second electrodes 314 and 414.

[0064] The materials constituting the high-resistance sections 419a and 419b are not particularly limited, but may be high-resistance conductive pastes that have been printed and cured. A specific example of such a high-resistance conductive paste is carbon paste. Specific examples of conductive particles contained in the carbon paste include carbon-based materials such as graphite, carbon black (furnace black, acetylene black, and Ketjen black), carbon nanotubes, and carbon nanofibers. Carbon ink may be used instead of the carbon paste. Furthermore, as the material constituting the second conductive layer 70, a conductive polymer such as PEDOT / PSS or indium tin oxide (ITO) may be used instead of the carbon paste described above.

[0065] Figure 5(b) is a plan view showing a second modified example of the heating element 417A in this embodiment. In this modified example, the heating element 417C is composed of a pair of thin wires 418b and 418c. The thin wires 418b and 418c are linear patterns having a meandering shape. The thin wires 418b and 418c extend along the Y direction overall. The thin wires 418b and 418c also include a plurality of first protrusions projecting toward the +X direction in the figure and a plurality of second protrusions projecting toward the -X direction in the figure. The first and second protrusions are arranged alternately along the Y direction.

[0066] Furthermore, the thin wires 418b and 418c are arranged symmetrically with respect to the second electrode 414. Specifically, the thin wires 418b and 418c are arranged point-symmetrically with respect to the center of the second electrode 414. By arranging the thin wires 418b and 418c symmetrically with respect to the second electrode 414 in this way, the heat distribution around the second electrode 414 can be made uniform.

[0067] In this modified example, the thin wire 418b is connected to the branch wiring 413a, while the thin wire 418c is connected to the branch wiring 413b. Furthermore, the materials constituting the thin wires 418b and 418c in this modified example are not particularly limited, but the same materials as those used for the thin wire 418a described above can be used as examples.

[0068] As shown in Figure 2(a), a spacer 5 is interposed between the upper electrode sheet 3 and the lower electrode sheet 4. The spacer 5 has an opening 53 that penetrates the spacer 5 in the thickness direction (Z direction in the figure). The third base material 50 of this spacer 5 is made of the same material as the first base material 30. However, the material constituting the third base material 50 may be an insulating material different from the material constituting the first base material 30.

[0069] The upper bonding layer 51 is interposed between the third substrate 50 and the upper electrode sheet 3, and bonds the third substrate 50 and the upper electrode sheet 3. The upper bonding layer 51 is not particularly limited, but may be composed of an adhesive material. Examples of adhesive materials, though not particularly limited, include acrylic resins, silicone resins, urethane resins, butyl rubber, LSE, etc.

[0070] The lower bonding layer 52 is interposed between the third substrate 50 and the lower electrode sheet 4, and bonds the third substrate 50 and the lower electrode sheet 4. The material constituting the lower bonding layer 52 is not particularly limited, but an example of an adhesive material similar to the adhesive material constituting the upper bonding layer 51 can be given.

[0071] The structure of the spacer 5 is not limited to the above. For example, the spacer 5 may have a resist layer made of a resist material. This resist layer can be formed by applying the resist material to the first substrate 30 or the second substrate 40 and curing it. Alternatively, the spacer 5 may be a laminate of this resist layer and an adhesive layer. Furthermore, an adhesive may be used instead of the adhesive material as the material constituting the bonding layer.

[0072] As shown in Figure 1, the heater control circuit 8 is a control circuit that controls the heater 2A. This heater control circuit 8 is electrically connected to the first conductor circuit 31 of the heater 2A. Power supplied from the power supply 100 is supplied to the first conductor circuit 31 via the heater control circuit 8. As described above, when pressure P is applied to the heater cell 7 and the first switch unit 6 of the heater cell 7 is turned on, current flows to the heat-generating part 417A of the heater cell 7, and the heat-generating part 417A generates resistive heat. That is, the first switch unit 6 is energized only in the part of the heater 2A to which pressure P is applied, and the heat-generating part 417A connected in series with the energized first switch unit 6 generates heat, so that the part to which pressure P is applied can be selectively heated.

[0073] With the heater unit 1A described above, by arranging the multiple heater cells 7 described above on the upper surface 401 of the second base material 40 of the heater 2A, the portion to which pressure P is applied can be selectively heated. The first switch section 6 (first and second electrodes 314, 414) of the heater cell 7 is an on / off switch that conducts current when pressure P is applied, and therefore it can operate without providing ICs or the like required for capacitive switches such as those in the above-mentioned patent document, thus enabling miniaturization of the heater unit 1A.

[0074] Furthermore, the conductor circuit included in the heater 2A in this embodiment is formed from only two conductor patterns (first and second conductor circuits 31 and 41). In this way, the number of conductor patterns required for the minimum operation of the heater 2A can be reduced, making it possible to miniaturize the heater 2A.

[0075] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit it. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0076] For example, in the above embodiment, the heater unit 1A generates heat only when pressure P is applied to the heater 2A, but it is not limited to this. The heater unit 1A may also have a function that allows it to generate heat even when pressure P is not applied to the heater 2A.

[0077] Figure 6 is a cross-sectional view showing a first modified example of the heater unit 1A in this embodiment. As shown in Figure 6, the heater unit 1B in this modified example further includes a second switch unit 9. This second switch unit 9 is interposed between the heater control circuit 8 and the first switch unit 6. The second switch unit 9 is a changeover switch that can switch the electrical connection destination of the heater control circuit 8 to either the first electrode 314 or the second electrode 414. The switching operation of the second switch unit 9 may be performed by electrical control or manually.

[0078] When the second switch unit 9 electrically connects the heater control circuit 8 to the first electrode 314, as described above, the heating element 417A generates heat only when the first electrode 314 and the second electrode 414 are in contact due to pressure P. On the other hand, when the second switch unit 9 electrically connects the heater control circuit 8 to the second electrode 414, current is supplied to the second electrode 414 without going through the first electrode 314, so the heating element 417A can generate heat regardless of whether the first switch unit 6 is on or off.

[0079] Furthermore, in the heater 2A of the above embodiment, the first conductor circuit 31 is provided with a power supply wiring 311 connected to the heater control circuit 8, but the second conductor circuit 41 may also be provided with a power supply wiring 311. In other words, both the power supply wiring 311 and the ground wiring 411 may be provided on the upper surface 401 of the second base material 40, and only the first electrode 314 may be provided on the lower surface 301 of the first base material 30.

[0080] Figure 7(a) is a cross-sectional view showing a first modified example of heater 2A in this embodiment. In this modified example, the first conductor circuit 31 of heater 2B has only a first electrode 314. On the other hand, the second conductor circuit 41 includes a power supply wiring 311 provided on the second base material 40, and this power supply wiring 311 is interposed between the second electrode 414 and the heater control circuit 8.

[0081] Furthermore, in this modified example, the second electrode 414 includes a first contact portion 415a and a second contact portion 415b. The first contact portion 415a is connected to the power supply wiring 311, and the second contact portion 415b is connected to the heating portion 417A via an intervening portion 416a (see Figure 4). The first contact portion 415a and the second contact portion 415b are not connected to each other and are separated.

[0082] In this modified example, when pressure is applied to the heater 2B, the first electrode 314 comes into contact with the first contact portion 415a and the second contact portion 415b. As a result, the first contact portion 415a and the second contact portion 415b are electrically connected via the first electrode 314.

[0083] Furthermore, in the heater 2A of the above embodiment, the first conductor circuit 31 does not have a heating element, but the first conductor circuit 31 may also have a heating element. Figure 7(b) is a cross-sectional view showing a second modified example of the heater 2A of this embodiment. In this modified example, the first conductor circuit 31 of the heater 2C includes a second heating element 317.

[0084] The second heating element 317 is connected in series with the first electrode 314 and is interposed between the first electrode 314 and the heater control circuit 8. The second heating element 317 generates heat when the first electrode 314 comes into contact with the second electrode 414. In this way, by providing the second heating element 317 in the first conductor circuit 31, heating elements can be uniformly provided around the first and second electrodes 314 and 414.

[0085] Furthermore, as shown in Figures 8, 9(a), and 9(b), the heater 2D in this embodiment may further include a plurality (12 in this example) of load transmission members 10. Figure 8 is a plan view showing a third modified example of the heater 2A in this embodiment. Figures 9(a) and 9(b) are cross-sectional views along the line IX-IX in Figure 8, where Figure 9(a) shows a state in which no pressure is applied to the first switch unit 6, and Figure 8(b) shows a state in which pressure P is applied to the first switch unit 6 via the load transmission members 10.

[0086] The load transmission member 10 concentrates the load applied to the heater 2D at a position corresponding to the first switch unit 6, thereby appropriately transmitting the load to the first switch unit 6. This load transmission member 10 ensures that the first switch unit 6 is more reliably turned on. As shown in Figure 8, the multiple load transmission members 10 are each arranged on the upper surface 302 of the first base material 30 of the upper electrode sheet 3 so as to correspond to the multiple first switch units 6. The load transmission members 10 may also be arranged on the lower surface 402 of the second base material 40 of the lower electrode sheet 4 (see Figures 9(a) and 9(b)) so as to correspond to the multiple first switch units 6.

[0087] The load transmission member 10 is not particularly limited, but a film can be used as an example. The width of the film is, for example, about 8 mm, and the thickness of the film is, for example, about 75 μm. Examples of materials that make up the load transmission member 10 include resin materials, metal materials, and mixed materials of resin materials and metal materials. The load transmission member 10 may be formed by printing a resin paste onto the upper surface 302 of the first substrate 30 and curing the resin paste. Alternatively, the load transmission member 10 may be formed by attaching a film to the upper surface 302 via an adhesive. Alternatively, the load transmission member 10 may be formed by a molding method such as injection molding.

[0088] As shown in Figures 9(a) and 9(b), the load transmission member 10 of this modified example can accurately apply pressure to the first switch section 6, especially when an object 1000 having a flat bottom surface 1001 wider than the opening 53 is placed in the position corresponding to the heater cell 7. When an object with such a bottom surface is placed in contact with the upper surface of the first base material, the object distributes and applies the load to parts other than the first switch section. In contrast, by positioning the load transmission member 10 in the position corresponding to the first switch section 6, the load from the bottom surface 1001 of the object 1000 can be concentrated on the first switch section 6 without being distributed. This makes it possible to accurately apply a pressure P to the first switch section 6 that is sufficient to more reliably turn the first switch section 6 into the ON state.

[0089] Furthermore, as shown in Figure 8, the planar shape of the load transmission member 10 in this embodiment is not particularly limited, but is circular. Note that the planar shape of the load transmission member 10 is not limited to a circular shape. For example, the planar shape of the load transmission member 10 may be rectangular or the like. Also, it is preferable that the planar shape of the load transmission member 10 corresponds to the planar shape of the opening 53.

[0090] As shown in Figure 9(a), the width D of this load transmission member 10 １ The width D of the opening 53 is ２ Smaller than (D １ <D ２). Furthermore, in a plan view, the area of the load transmission member 10 is smaller than the area of the opening 53. Thus, the width D of the load transmission member 10 １ is smaller than the width D of the opening 53 ２ , whereby the load transmission member 10 can bend the upper electrode sheet 3 to reliably enter the opening 53, and thus the first electrode 314 can be more reliably brought into contact with the second electrode 414.

[0091] Furthermore, the thickness T of the load transmission member 10 １ may be substantially the same as the thickness T of the third base material 50 of the spacer 5 ２ (T １ = T ２ ). When the thickness T of the load transmission member 10 １ is substantially the same as the thickness T of the third base material 50 ２ , the thickness T of the load transmission member 10 １ is substantially equal to the distance between the first electrode 314 and the second electrode 414. Therefore, when the load transmission member 10 is pressed by the bottom surface 1001 of the object 1000, the first electrode 314 can be reliably brought into contact with the second electrode 414. Note that the thickness T of the load transmission member 10 １ may be larger than the thickness T of the third base material 50 of the spacer 5 ２ (T １ > T ２ ), or may be smaller than the thickness T of the third base material 50 of the spacer 5 ２ (T １ < T ２ ).

[0092] 1A, 1B... Heater unit 2A-2D... Heater 3... Upper electrode sheet 30... First base material 31... First conductor circuit 311... Power supply wiring 312... Main wiring 313... Branch wiring 314... First electrode 315... Second heating element 4... Lower electrode sheet 40... Second base material 41... Second conductor circuit 411... Ground wiring 412... Main wiring 413, 413a, 413b... Branch wiring 414... Second electrode 417A-417C... First heating element 418a, 418b... Fine wire 419a, 419b... High resistance section 5... Spacer 50... Third base material 53... Opening 6... First switch section 7... Heater cell 8... Heater control circuit 9... Second switch section 10... Load transmission member

Claims

1. A heater comprising a plurality of heater cells arranged on the same plane, each of which includes a first switch section that conducts current when pressure is applied, and a heating section connected in series with the first switch section and generating heat due to electrical resistance.

2. A heater according to claim 1, wherein the heater further comprises a first lead wire and a second lead wire spaced apart from the first lead wire, and the plurality of heater cells are connected in parallel to the first and second lead wires.

3. A heater according to claim 1 or 2, the heater further comprising: a first substrate; a second substrate facing the first substrate; and a spacer having an opening and interposed between the first substrate and the second substrate, wherein the heating portion is provided on the first substrate or the second substrate, and the first switch portion includes: a first electrode provided on the first substrate; and a second electrode provided on the second substrate so as to face the first electrode through the opening.

4. A heater according to claim 3, wherein the heating element is provided on the second substrate and connected in series with the second electrode.

5. A heater according to any one of claims 1 to 4, wherein the electrical resistance value of the heating element is higher than the electrical resistance value of the first switch element.

6. A heater according to any one of claims 1 to 5, wherein the heating element includes a thin wire having a cross-sectional area smaller than the cross-sectional area of ​​the first switch element.

7. A heater according to claim 6, wherein the thin wire extends so as to surround the first switch portion.

8. A heater according to any one of claims 1 to 7, wherein the electrical resistivity of the first material constituting the heating element is greater than the electrical resistivity of the second material constituting the first switch element.

9. A heater according to any one of claims 1 to 8, wherein the heating portion includes a first portion connected in series with the first switch portion and a second portion connected in series with the first switch portion and separated from the first portion, the first portion and the second portion being arranged symmetrically with respect to the first switch portion.

10. The heater according to claim 9, the heater further comprising: a first substrate; a second substrate facing the first substrate; a spacer having an opening and interposed between the first substrate and the second substrate; a first lead wiring provided on the first substrate; and a second lead wiring provided on the second substrate, wherein the heating portion is provided on the first substrate or the second substrate; the first switch portion includes: a first electrode provided on the first substrate; and a second electrode provided on the second substrate so as to face the first electrode through the opening; the second lead wiring includes: a third lead wiring provided on the second substrate so as to be adjacent to the second electrode with a space between them; and a fourth lead wiring provided on the second substrate so as to be positioned on the opposite side of the second electrode from the third lead wiring; The first portion is interposed between the third lead-out wiring and the second electrode, and the second portion is interposed between the fourth lead-out wiring and the second electrode, and the first and second portions are arranged symmetrically with respect to the second electrode.

11. A heater according to any one of claims 1 to 10, wherein the heater further comprises a plurality of load transmission members, each positioned at a location corresponding to a plurality of first switch portions, and each of the load transmission members transmits the load to the plurality of first switch portions when pressed by a load from outside the heater.

12. The heater according to claim 11, wherein the heater further comprises: a first substrate; a second substrate facing the first substrate; and a spacer having an opening and interposed between the first substrate and the second substrate, the heating portion being provided on the first substrate or the second substrate, the first switch portion including: a first electrode provided on the first substrate; and a second electrode provided on the second substrate so as to face the first electrode through the opening, and the plurality of load transmission members being arranged on the first substrate or the second substrate so as to correspond to the plurality of first switch portions.

13. A heater according to claim 12, wherein the width of the load transmission member is smaller than the width of the opening.

14. A heater unit comprising a heater according to any one of claims 1 to 13, and a heater control circuit that supplies current to the heater cell to generate heat in the heating element.

15. A heater unit according to claim 14, wherein the heater further comprises: a first substrate; a second substrate facing the first substrate; and a spacer having an opening and interposed between the first substrate and the second substrate; the first switch portion includes: a first electrode provided on the first substrate; and a second electrode provided on the second substrate so as to face the first electrode through the opening; the heating portion is provided on the second substrate and connected in series with the second electrode; and the heater unit further comprises: a second switch portion interposed between the heater control circuit and the first switch portion, and for switching the electrical connection destination of the heater control circuit to the first electrode or the second electrode.

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