Pressure sensitive sensor

Abstract

A pressure-sensitive sensor (1A) includes a substrate (11), a resistor (14) provided on the substrate (11), a wiring pattern (12) provided on the substrate (11) and connected to the resistor, comb-tooth patterns (15B to 15J) provided on the substrate (11) and each independently connected to the resistor, a substrate (21) opposed to the comb-tooth patterns and having a pressing portion capable of approaching the substrate (11), a spacer (30) having an opening (31) and interposed between the substrates (11, 12), a connecting body (22) provided on the substrate (21), and a wiring pattern (16) provided on the substrate (11) in a manner opposed to the connecting body via the opening and electrically connected to the connecting body due to pressing of the pressing portion, the resistor being arranged at a position not overlapping the connecting body in plan view, and a resistance value between the wiring patterns (12, 16) changing according to a load applied to the pressing portion.

Description

Technical Field

[0001] The present invention relates to a pressure sensor whose resistance value varies according to the applied load.

[0002] For the designated countries that recognize the inclusion based on document citation, the contents of Japanese Patent Application No. 2020-208233, filed on December 16, 2020, are incorporated herein by reference as part of this specification. Background Technology

[0003] A conventional pressure sensor comprises: an upper circuit board having a pair of comb-shaped electrodes that interlock with each other; and a lower circuit board having a disk-shaped electrode opposite to the comb-shaped electrodes. In this pressure sensor, at least one of the three electrodes serves as a pressure-sensitive resistor (for example, refer to Patent Document 1 (paragraphs

[0002] to

[0005] )). Figure 1 (a)~ Figure 1 (c)). Another existing pressure sensor includes: an upper circuit board having a disk-shaped pressure-sensitive resistor; and a lower circuit board having a disk-shaped counter electrode opposite the pressure-sensitive resistor (see, for example, Patent Document 1 (paragraphs

[0006] to

[0008] ). Figure 2 (a)~ Figure 2 (c))).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2002-158103 Summary of the Invention

[0007] (a) Technical problems to be solved

[0008] Regarding the aforementioned pressure sensors, when the upper circuit board is pressed from above, the electrodes located below the pressing portion come into direct contact with each other. Furthermore, if the pressing force increases further, the contact area between the electrodes increases, and the resistance decreases. Since these pressure sensors detect pressing force based on changes in the area of ​​direct contact with the resistive element, they suffer from the problem of not being able to consistently obtain good output characteristics.

[0009] The technical problem to be solved by the present invention is to provide a pressure-sensitive sensor that can stably obtain good output characteristics.

[0010] (II) Technical Solution

[0011] (1) The pressure-sensitive sensor of the present invention comprises: a first substrate; a resistive element disposed on the first substrate; a first wiring pattern disposed on the first substrate and connected to the resistive element; a plurality of first comb patterns disposed on the first substrate and each independently connected to the resistive element; a pressing unit opposite to the first comb patterns and having: a pressing portion capable of approaching the first substrate, and a connector held on the pressing portion and electrically connected to the first comb patterns by pressing the pressing portion; and a second wiring pattern disposed on the first substrate and connected to the first comb patterns by pressing the first substrate. The resistive element is electrically connected to the connector by pressing the pressing part, or it is included in the pressing unit and connected to the connector. The resistivity of the material constituting the resistive element is higher than the resistivity of the following materials: the resistivity of the material constituting the first wiring pattern, the resistivity of the material constituting the first comb pattern, the resistivity of the material constituting the connector, and the resistivity of the material constituting the second wiring pattern. The resistive element is positioned in a position that does not overlap with the connector when viewed from above. The resistance value between the first wiring pattern and the second wiring pattern varies according to the load applied to the pressing part.

[0012] (2) In the above invention, the first wiring pattern may be connected to one end of the resistor, and the plurality of first comb patterns may be connected between one end and the other end of the resistor in a state of being spaced apart from each other along the length direction of the resistor.

[0013] (3) In the above invention, the plurality of first comb patterns may be spaced apart and substantially parallel to each other in the opposing region of the first substrate opposite to the connector.

[0014] (4) In the above invention, the plurality of first comb patterns may be arranged at intervals from the inside to the outside in the opposite region.

[0015] (5) In the above invention, the plurality of first comb patterns may be arranged in a concentric circle with a specific point as the center in the opposite area of ​​the first substrate opposite to the connector.

[0016] (6) In the above invention, the specific point may be the center of the opposing region.

[0017] (7) In the above invention, each of the first comb tooth patterns may include: a detection part disposed in the opposite region; and a lead-out part that electrically connects the detection part to the resistive element.

[0018] (8) In the above invention, the detection portion of the plurality of first comb patterns may include portions that are spaced apart and substantially parallel to each other in the opposing region of the first substrate opposite to the connector.

[0019] (9) In the above invention, the detection portion of the plurality of first comb patterns may include portions arranged at intervals from the inside to the outside in the opposing region.

[0020] (10) In the above invention, the detection portion of the plurality of first comb patterns may include a portion arranged in a concentric circle around a specific point in the opposing region of the first substrate opposite to the connector.

[0021] (11) In the above invention, the front end of the second wiring pattern may be an expanded diameter portion that is wider than other portions of the second wiring pattern.

[0022] (12) In the above invention, the plurality of first comb patterns may be disposed on the first substrate in such a way that the connection position of the first comb pattern with the resistor is closer to the other end of the resistor, then the first comb pattern is located near a specific point in the area opposite to the first substrate opposite to the connector.

[0023] (13) In the above invention, the resistive element may be formed by printing carbon paste or carbon ink containing carbon particles and then curing it.

[0024] (14) In the above invention, the pressure sensor may further include a third wiring pattern, which is disposed on the first substrate and connected to the other end of the resistor, wherein the resistivity of the material constituting the resistor is higher than the resistivity of the material constituting the third wiring pattern.

[0025] (15) In the above invention, the pressure sensor may further include: a third wiring pattern disposed on the first substrate and connected to the other end of the resistive element; a second comb pattern disposed on the first substrate and connected to the first wiring pattern in a manner opposite to the connector; and a third comb pattern disposed on the first substrate and connected to the third wiring pattern in a manner opposite to the connector, wherein the resistivity of the material constituting the resistive element is higher than the resistivity of the material constituting the third wiring pattern, the resistivity of the material constituting the second comb pattern, and the resistivity of the material constituting the third comb pattern, wherein the first comb pattern, the second comb pattern, and the third comb pattern are spaced apart and substantially parallel in the opposing region of the first substrate opposite to the connector.

[0026] (16) In the above invention, the pressing unit may include: a second substrate having the connector; and a spacer between the first substrate and the second substrate, the spacer having an opening that aligns the connector with the first comb pattern.

[0027] (17) In the above invention, the second wiring pattern may be disposed on the first substrate in a manner opposite to the connector.

[0028] (18) In the above invention, the specific point may be the front end of the second wiring pattern.

[0029] (19) In the above invention, the second wiring pattern can be connected to the resistor.

[0030] (20) In the above invention, the first wiring pattern and the third wiring pattern may apply a predetermined voltage to the resistive element, and the second wiring pattern may output a voltage corresponding to the load applied to the pressing part.

[0031] (21) In the above invention, the number of the first comb pattern electrically connected to the connector may vary according to the load applied to the pressing part, thereby changing the resistance value between the first wiring pattern and the second wiring pattern.

[0032] (III) Beneficial Effects

[0033] In this invention, the resistive element is positioned so as not to overlap with the connector when viewed from above. As the pressing part is pressed, the connector is electrically connected to the comb pattern attached to the resistive element. Therefore, in this invention, the resistive element does not contact the connector, thus providing a pressure-sensitive sensor capable of stably obtaining good output characteristics. Attached Figure Description

[0034] Figure 1 This is a top view showing the pressure-sensitive sensor in the first embodiment of the present invention.

[0035] Figure 2 It is along Figure 1 A sectional view along line II-II.

[0036] Figure 3 This is a top view showing the lower film substrate in the first embodiment of the present invention.

[0037] Figure 4 This is a bottom view showing the spacer and the upper film substrate in the first embodiment of the present invention.

[0038] Figure 5 This is a top view showing a modified example of the comb pattern in an embodiment of the present invention.

[0039] Figure 6 (a)~ Figure 6 (c) is a cross-sectional view showing the operation of the pressure sensor in the first embodiment of the present invention, wherein, Figure 6 (a) is a diagram showing the state in which the connector begins to contact the comb pattern; Figure 6 (b) indicates that it is related to Figure 6 (a) is a diagram comparing the state with the increased load applied; Figure 6 (c) indicates that it is related to Figure 6 (b) is a diagram of the state with a further increase in load compared to the state with the load applied.

[0040] Figure 7 This is a top view showing the pressure-sensitive sensor in the second embodiment of the present invention.

[0041] Figure 8 It is along Figure 7 A cross-sectional view of line VIII-VIII.

[0042] Figure 9 This is a top view showing the lower film substrate in the second embodiment of the present invention.

[0043] Figure 10 This is a bottom view showing the spacer and the upper film substrate in the second embodiment of the present invention.

[0044] Figure 11 This is a cross-sectional view showing the pressure-sensitive sensor in the third embodiment of the present invention.

[0045] Figure 12 This is a cross-sectional view showing a modified example of the pressure-sensitive sensor in the third embodiment of the present invention.

[0046] Figure 13 This is a cross-sectional view showing the lower membrane substrate of the pressure-sensitive sensor according to the fourth embodiment of the present invention. Detailed Implementation

[0047] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0048] <<First Implementation Method>>

[0049] Figure 1 This is a top view showing the pressure-sensitive sensor according to the first embodiment of the present invention. Figure 2 It is along Figure 1 A sectional view along line II-II. Additionally... Figure 3 This is a top view showing the lower film substrate in this embodiment. Figure 4 This is a bottom view showing the spacer and the upper film substrate in this embodiment.

[0050] In this embodiment, the pressure sensor 1A is a sensor whose resistance value changes according to the magnitude of the applied load. For example... Figures 1-4 As shown, the pressure-sensitive sensor 1A includes a lower membrane substrate 10, an upper membrane substrate 20, and a spacer 30. In this embodiment, the upper membrane substrate 20 and the spacer 30 correspond to an example of the "pressing unit" in this invention, and the spacer 30 in this embodiment corresponds to an example of the "spacer" in this invention.

[0051] like Figure 3 As shown, the lower film substrate 10 is a wiring board having a substrate 11, wiring patterns 12 and 13, a resistor 14, comb patterns 15A to 15K and wiring pattern 16.

[0052] In this embodiment, substrate 11 corresponds to an example of the "first substrate" in this invention; wiring pattern 12 corresponds to an example of the "first wiring pattern" in this invention; wiring pattern 13 corresponds to an example of the "third wiring pattern" in this invention; and wiring pattern 16 corresponds to an example of the "second wiring pattern" in this invention. Furthermore, comb tooth pattern 15A corresponds to an example of the "second comb tooth pattern" in this invention; comb tooth patterns 15B to 15J correspond to an example of the "first comb tooth pattern" in this invention; and comb tooth pattern 15K corresponds to an example of the "third comb tooth pattern" in this invention.

[0053] The substrate 11 is a film-like component made of a flexible and electrically insulating material. Examples of materials constituting the substrate 11 include resin materials, and more specifically, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Alternatively, the substrate 11 may not be flexible.

[0054] Wiring patterns 12 and 13 are formed by printing a conductive paste onto the upper surface of the substrate 11 and then curing (hardening) it. The conductive paste is composed of conductive particles and adhesive resin mixed with water or solvent, as well as various additives. The conductive paste constituting the wiring patterns 12 and 13 is a low-resistance conductive paste with a relatively small resistance value. Furthermore, the method for forming the wiring patterns 12 and 13 is not particularly limited to the method described above. For example, instead of a conductive paste, the wiring patterns 12 and 13 can also be formed by etching a metal foil.

[0055] Specific examples of conductive particles include silver, copper, nickel, tin, bismuth, zinc, indium, palladium, and their alloys. Specific examples of adhesive resins include acrylic resins, polyester resins, epoxy resins, vinyl resins, polyurethane resins, phenolic resins, polyimide resins, silicone resins, and fluororesins. Furthermore, examples of solvents contained in conductive pastes include α-terpineol, butyl carbitol acetate, butyl carbitol, 1-decyl alcohol, butyl cellosolve, diethylene glycol monoethyl ether acetate, and tetradecane.

[0056] While not specifically limited, in this embodiment, a silver paste with silver as the main component of conductive particles or a copper paste with copper as the main component of conductive particles is used as the low-resistance conductive paste. Furthermore, metal salts can be used as the conductive particles contained in the conductive paste. Examples of metal salts include the aforementioned metal salts. Additionally, the binder resin can be omitted from the aforementioned conductive paste. Alternatively, conductive ink can be used instead of the aforementioned conductive paste.

[0057] The coating method for the conductive paste is not particularly limited, and either contact coating or non-contact coating methods can be used. Specific examples of contact coating methods include screen printing, gravure printing, offset printing, gravure-offset printing, and flexographic printing. On the other hand, specific examples of non-contact coating methods include inkjet printing, spraying, dispensing, and jet dispensing. Furthermore, the heat source for curing the conductive paste is not particularly limited, and examples include electric ovens, infrared ovens, far-infrared (IR) furnaces, near-infrared (NIR) furnaces, laser irradiation devices, or combinations thereof.

[0058] In this embodiment, wiring pattern 12 extends linearly along the X direction in the figure. The end 121 of wiring pattern 12 is covered by resistor 14, and a comb pattern 15A is connected to the end 121. Similarly, wiring pattern 13 also extends linearly along the X direction in the figure. The end 131 of wiring pattern 13 is covered by resistor 14, and a comb pattern 15K is connected to the end 131. Although not specifically illustrated, one wiring pattern 12 is connected to the power supply, while the other wiring pattern 13 is grounded. Furthermore, the planar shape of wiring patterns 12 and 13 is linear, but not limited to the straight line shape described above.

[0059] The ends 121 of wiring pattern 12 and the ends 131 of wiring pattern 13 are separated along the Y direction in the figure. A resistor 14 is disposed along the Y direction in the figure, with one end 141 covering the end 121 of wiring pattern 12 and the other end 142 covering the end 131 of wiring pattern 13. Therefore, one wiring pattern 12 and another wiring pattern 13 are electrically connected via the resistor 14. The resistor 14 is disposed in the substrate 11 at a position away from the opposing region 111 (described later) in a manner that does not overlap with the connector 22 of the upper film substrate 20 when viewed from above.

[0060] Similar to the wiring patterns 12 and 13 described above, the resistor 14 is also formed by printing a conductive paste onto the upper surface of the substrate 11 and then curing it. The conductive paste constituting the resistor 14 is a high-resistivity conductive paste with a higher resistance value compared to the low-resistivity conductive paste described above. The conductive paste constituting the resistor 14 contains conductive particles with a resistivity higher than that of the conductive particles constituting the conductive pastes of the wiring patterns 12 and 13. That is, the resistor 14 is made of a material with a resistivity higher than that of the materials constituting the wiring patterns 12 and 13, and the resistance value of the resistor 14 is sufficiently higher than the resistance values ​​of the wiring patterns 12 and 13 to the point that the resistance values ​​of the wiring patterns 12 and 13 can be ignored. Specifically, the resistance value of the resistor 14 is at least 10 times the resistance value of the wiring patterns 12 and 13, and preferably at least 100 times the resistance value of the wiring patterns 12 and 13. In addition, the resistivity of the material constituting the resistor 14 is at least 10 times that of the resistivity of the material constituting the wiring patterns 12 and 13, preferably at least 100 times.

[0061] Carbon paste can be cited as a specific example of such a high-resistivity conductive paste. Specific examples of conductive particles contained in the conductive paste constituting the resistive body 14 include carbon-based materials such as graphite, carbon black (furnace black, acetylene black, Ketjen black), carbon nanotubes, and carbon nanofibers. Alternatively, carbon ink can be used instead of the aforementioned carbon paste.

[0062] Similar to the wiring patterns 12 and 13 described above, a plurality of (11 in this example) comb patterns 15A to 15K are formed by printing a low-resistivity conductive paste onto the substrate 11 and then curing it. That is, each comb pattern 15A to 15K is made of a material with a resistivity lower than that of the material constituting the resistor 14, and the resistance value of the resistor 14 is sufficiently higher than the resistance value of the comb pattern 15A to 15K to the point that the resistance value of each comb pattern 15A to 15K is negligible. Specifically, the resistance value of the resistor 14 is at least 10 times the resistance value of the comb patterns 15A to 15K, preferably at least 100 times the resistance value of the comb patterns 15A to 15K. Furthermore, the resistivity of the material constituting the resistor 14 is at least 10 times, preferably at least 100 times, the resistivity of the material constituting the comb patterns 15A to 15K. The method for forming the comb patterns 15A to 15K is not particularly limited to the method described above. For example, it can also replace conductive paste and form comb patterns 15A to 15K by etching metal foil.

[0063] Similar to the wiring patterns 12 and 13 described above, wiring pattern 16 is also formed by printing a low-resistance conductive paste onto the upper surface of the substrate 11 and then curing it. That is, the wiring pattern 16 is made of a material with a lower resistivity than the material constituting the resistor 14, and the resistance value of the resistor 14 is sufficiently higher than the resistance value of the wiring pattern 16 to the point that the resistance value of the wiring pattern 16 is negligible. Specifically, the resistance value of the resistor 14 is at least 10 times the resistance value of the wiring pattern 16, preferably at least 100 times the resistance value of the wiring pattern 16. Furthermore, the resistivity of the material constituting the resistor 14 is at least 10 times the resistivity of the material constituting the wiring pattern 16, preferably at least 100 times. The method for forming the wiring pattern 16 is not particularly limited to the methods described above. For example, instead of a conductive paste, the wiring pattern 16 can be formed by etching a metal foil.

[0064] In this embodiment, each comb pattern 15A-15K has a straight portion 151 and an arc portion 152. The straight portion 151 of each comb pattern 15A-15K extends in a straight line along the X direction in the figure, and a portion of the straight portion 151 is located outside the opposing region 111. In contrast, the arc portion 152 of each comb pattern 15A-15K is located in the opposing region 111 and is electrically connected to the resistor 14 via the straight portion 151. Here, the opposing region 111 refers to the circular area on the upper surface of the substrate 11 that is opposite the connector 22 of the upper film substrate 20 when viewed from above.

[0065] In this embodiment, the portion of the comb patterns 15A-15K located in the opposing region 111 functions as a detection section 155 for detecting the load applied to the pressure sensor 1A, and this detection section 155 includes an arc portion 152. Conversely, the portion of the comb patterns 15A-15K located outside the opposing region 11 functions as a lead-out portion 156 for electrically connecting the detection section 155 to the resistor 14, and this lead-out portion 156 includes a portion of a straight line portion 151.

[0066] For the multiple comb patterns 15A to 15K, apart from the electrical connection via the resistor 14 on the substrate 11, the comb patterns 15A to 15K are spaced apart to ensure mutual electrical insulation. Furthermore, the number of comb patterns is not particularly limited to the above method, but as will be described later, the more comb patterns 15A to 15K there are, the narrower the spacing between them, and the higher the resolution of the pressure sensor 1A's output.

[0067] Furthermore, in this embodiment, the comb tooth patterns 15A to 15K have substantially the same width, but this is not particularly limited; the line widths of the comb tooth patterns 15A to 15K may also be different. Additionally, in this embodiment, each comb tooth pattern 15A to 15K has substantially the same width over its entire length, but this is not particularly limited; each comb tooth pattern 15A to 15K may also have locally different widths.

[0068] In the 11 comb patterns 15A to 15K, the straight portions 151 of the comb patterns 15A and 15K at both ends are connected to the ends 121 and 131 of the wiring patterns 12 and 13, respectively. The straight portions 151 of the remaining 9 comb patterns 15B to 15J are covered by the resistor 14, and these comb patterns 15B to 15J are connected to the resistor 14. Alternatively, the comb patterns 15A and 15K at both ends may not be directly connected to the wiring patterns 12 and 13, but may be embedded in the resistor 14 in the same way as the comb patterns 15B to 15J.

[0069] The straight sections 151 of the inner comb patterns 15B to 15J are connected between one end 141 and the other end 142 of the resistor 14, spaced apart from each other along the length direction (Y direction in the figure). Each comb pattern 15B to 15J is independently connected to the resistor 14. That is, the resistor 14 is located between the ends of the straight sections 151 of the comb patterns 15B to 15J. Furthermore, the resistor 14 is also located between the end 121 of the wiring pattern 12 and the end of the straight section 151 of the comb pattern 15B, and also between the end 131 of the wiring pattern 13 and the end of the straight section 151 of the comb pattern 15J.

[0070] In addition, in this embodiment, the comb patterns 15B to 15J are substantially equally spaced and connected to the resistor 14. However, it is not particularly limited to this as long as the comb patterns 15B to 15J are spaced apart from each other and connected to the resistor 14. For example, although not specifically illustrated, it is also possible that the connection interval between the comb pattern and the resistor becomes narrower as the position of the comb pattern in the opposing region moves closer to the outside.

[0071] The straight portions 151 of the 11 comb patterns 15A to 15K extend in a straight line from the resistor 14 toward the opposing region 111 in the -X direction in the figure, spaced apart and extending substantially parallel to each other. The wiring pattern 16 also extends substantially parallel to the straight portions 151 of the comb patterns 15K, spaced apart, but the wiring pattern 16 extends to the center CP of the opposing region 111 and has a front end portion 161 at the center CP.

[0072] The front end portion 161 becomes a circular enlarged portion with a diameter larger than the width of other portions of the wiring pattern 16 (e.g., portions of the wiring pattern 16 other than the front end portion 161 within the opposing region 111). Thus, by having the enlarged portion 161 at the front end of the wiring pattern 16, stabilization of load detection at the start of pressing can be achieved. Furthermore, the planar shape of the enlarged portion 161 is not limited to a circle; for example, it can be elliptical, oblong, rectangular, or polygonal. Alternatively, the wiring pattern 16 may not have an enlarged portion at its front end.

[0073] In contrast, the comb patterns 15A to 15K are spaced apart in the opposing region 111 and extend substantially parallel to each other, surrounding the front end portion 161 of the wiring pattern 16. More specifically, in this embodiment, the comb patterns 15A to 15K each have an arcuate portion 152 in the opposing region 111 that extends in an arc shape surrounding the front end portion 161 of the wiring pattern 16. The arcuate portions 152 of the plurality of comb patterns 15A to 15K are arranged concentrically with the front end portion 161 of the wiring pattern 16 as the center.

[0074] Furthermore, in this embodiment, the arcuate portions 152 of the comb tooth patterns 15B to 15J are substantially equally spaced, but the arrangement of the arcuate portions 152 is not particularly limited thereto, as long as the spacing between the arcuate portions 152 is ensured. For example, although not specifically illustrated, it is also possible that the spacing between the arcuate portions of the comb tooth patterns becomes narrower as the position of the comb tooth patterns in the opposing regions moves closer to the outer side.

[0075] Furthermore, in this embodiment, the pressing start position of the pressing member (described later) (the contact start position of the connector 22 relative to the lower film substrate 10) is described as substantially consistent with the center CP of the opposing region 111. However, this pressing start position can also be a position other than the center CP of the opposing region 111, and can be arbitrarily set as long as it is within the opposing region 111. In this case, the comb pattern is arranged in concentric circles with the pressing start position other than the center CP of the opposing region 111 as the center. This pressing start position corresponds to an example of a "specific point" in this invention.

[0076] Furthermore, on the substrate 11, the aforementioned wiring pattern 16 is electrically insulated from the innermost comb pattern 15K, but this is not particularly limiting; the wiring pattern 16 may also have a connecting line that connects to the comb pattern 15K. In this way, by electrically connecting the wiring pattern 16 and the comb pattern 15K via the connecting line, the output of the pressure sensor 1A in the non-pressed state can be set to a desired value.

[0077] Furthermore, the shape of the detection section for the comb pattern is not particularly limited to the shape described above, as long as multiple comb patterns are arranged at intervals from the inside to the outside in the opposing region. Although not particularly limited, the shape of the detection section for the comb pattern can be, for example, set to... Figure 5 The shape shown. Figure 5 This is a top view showing a modified example of the comb pattern in this embodiment.

[0078] For example, such as Figure 5 As shown, the comb patterns 15A to 15K can also have curved portions 153 that are substantially right-angled and have a generally U-shaped shape instead of the arc portion 152 in the opposing region 111. The curved portions 153 of the plurality of comb patterns 15A to 15K are spaced apart and substantially parallel to each other in a manner that surrounds the front end portion 161 of the wiring pattern 16, and are arranged spaced apart from the inside to the outside of the opposing region 111.

[0079] In addition, Figure 5 In the variation shown, the pressing start position of the pressing member can also be set at any position within the opposing region 111 other than the center CP. In this case, the comb pattern is spaced apart and arranged substantially parallel to each other in a manner that surrounds the pressing start position outside the center CP of the opposing region 111.

[0080] Furthermore, in this embodiment, the comb patterns 15A to 15K extend in a straight line outside the opposing region 111, but the planar shape of the comb patterns outside the opposing region is not particularly limited to this, as long as it is linear. Additionally, in this embodiment, the comb patterns 15A to 15K are also substantially parallel outside the opposing region 111, but this is not particularly limited; multiple comb patterns may also be substantially non-parallel outside the opposing region.

[0081] like Figure 4 As shown, the upper film substrate 20 includes a substrate 21 and a connector 22. In this embodiment, the substrate 21 corresponds to an example of the "second substrate" in this invention.

[0082] Similar to the substrate 11 described above, the substrate 21 is a film-like component made of a flexible and electrically insulating material. Examples of materials constituting the substrate 21 include resin materials, and more specifically, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). Furthermore, a metal film can also be used as the substrate 21; in this case, the substrate 21 can also function as a connector 22, meaning the substrate 21 can also serve as a connector 22.

[0083] like Figure 1 and Figure 4 As shown, the connector 22 has a planar shape that corresponds to the shape of the arcuate portion 152 of the comb patterns 15A to 15K on the lower film substrate 10. More specifically, the connector 22 has a circular shape with a diameter larger than the diameter of the arcuate portion 152 of the outermost comb pattern 15A. In this embodiment, the connector 22 has a diameter larger than the opening 31 of the spacer 30, but it is not particularly limited to this, and the connector 22 may also have a diameter smaller than the inner diameter of the opening 31. The connector 22 is formed on the substrate 21 such that when the film substrates 10 and 20 are laminated via the spacer 30, it is opposite to the arcuate portion 152 of the comb patterns 15A to 15K, and the center of the connector 22 overlaps with the front end portion 161 of the wiring pattern 16.

[0084] Similar to the wiring patterns 12 and 13 described above, the connector 22 is formed by printing a low-resistance conductive paste onto the lower surface of the substrate 21 and then curing it. That is, the connector 22 is made of a material with a lower resistivity than the material constituting the resistor 14, and the resistance value of the resistor 14 is sufficiently higher than the resistance value of the connector 22 to the point that the resistance value of the connector 22 is negligible. Specifically, the resistance value of the resistor 14 is at least 10 times the resistance value of the connector 22, preferably at least 100 times the resistance value of the connector 22. Furthermore, the resistivity of the material constituting the resistor 14 is at least 10 times, preferably at least 100 times, the resistivity of the material constituting the connector 22.

[0085] Furthermore, the connector 22 may also have a protective layer covering the aforementioned layer formed by printing a conductive paste of a resistive material and then curing it. This protective layer is formed by printing a high-resistance conductive paste that has a higher resistance value than the aforementioned low-resistance conductive paste and then curing it. Specific examples of such a high-resistance conductive paste are not particularly limited; for example, carbon paste can be exemplified.

[0086] Similar to the substrates 11 and 21 described above, the spacer 30 is a film-like component made of a flexible and electrically insulating material. Examples of materials constituting the substrate 30 include resin materials, and more specifically, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN).

[0087] like Figure 1 and Figure 4 As shown, the spacer 30 has a circular opening 31 corresponding to the shape of the arcuate portions 152 of the comb patterns 15A-15K on the lower film substrate 10. More specifically, the opening 31 has a circular shape with an inner diameter larger than the diameter of the outermost arcuate portion 152 of the comb pattern 15A. Although not particularly limited, when viewed from above, the distance between the opening 31 and the outermost arcuate portion 152 of the comb pattern 15A is preferably greater than the thickness of the spacer 30. The opening 31 is formed at a position corresponding to the arcuate portions 152 of the comb patterns 15A-15K on the lower film substrate 10 and the connector 22 on the upper film substrate 20. When the film substrates 10 and 20 are laminated via the spacer 30, the arcuate portions 152 of the comb patterns 15A-15K and the connector 22 are opposite each other via the opening 31.

[0088] Furthermore, the planar shape of the opening 31 is not limited to a circle; for example, it can be an ellipse, an oblong shape, a rectangle, or a polygon. Additionally, the shapes of the connecting portion 22 and the detection portions 155 of the comb patterns 15A to 15K are not particularly limited to the shapes described above; for example, they can be shapes corresponding to the shape of the opening 31. Furthermore, in this embodiment, the portion of the substrate 21 of the upper film substrate 20 opposite to the opening 31 corresponds to an example of the "pressing portion" in this invention.

[0089] The lower film substrate 10 and the upper film substrate 20 are stacked via spacers 30. Specifically, the upper surface of the substrate 11 of the lower film substrate 10 and the lower surface of the spacer 30 are bonded together via an adhesive layer (not shown), and the upper surface of the spacer 30 and the lower surface of the substrate 21 of the upper film substrate 20 are bonded together via an adhesive layer (not shown).

[0090] At this time, as Figure 1 As shown, viewed from above, the center CP of the opposing region 111 of the lower film substrate 10 substantially coincides with the center of the opening 31 of the spacer 30. Furthermore, viewed from above, this center CP overlaps with the front end 161 of the wiring pattern 16 of the lower film substrate 10 and is also substantially aligned with the center of the connector 22 of the upper film substrate 20. Moreover, via the opening 31 of the spacer 30, the connector 22 of the upper film substrate 20 is opposed to the front end 161 of the wiring pattern 16 of the lower film substrate 10 and the arcuate portions 152 of the comb patterns 15A to 15K.

[0091] like Figure 2 As shown, the spacer 30 ensures a gap between the connector 22 and the front end 161 of the wiring pattern 16, and also ensures a gap between the connector 22 and the comb patterns 15A to 15K. As described later, the substrate 21 of the upper film substrate 20 deforms under the load applied by the pressing member. Through this deformation, the connector 22 contacts and is electrically connected to the front end 161 of the wiring pattern 16, and the connector 22 contacts and is electrically connected to the comb patterns 15A to 15K.

[0092] Furthermore, in this embodiment, the thickness of the spacer 30 is set such that the connector 22 does not contact the comb patterns 15A-15K and the wiring pattern 16 when not pressed, but it is not particularly limited to this. Alternatively, the thickness of the spacer 30 may be set such that the connector 22 is always in contact with the comb patterns 15A-15K and the wiring pattern 16.

[0093] In this embodiment, "electrically connecting" the connector to the comb pattern means that the resistance between the connector and the comb pattern is below a predetermined threshold, excluding the state described above where the connector and the comb pattern are simply in contact when not pressed. Similarly, in this embodiment, "electrically connecting" the connector to the wiring pattern means that the resistance between the connector and the wiring pattern is below a predetermined threshold, excluding the state described above where the connector and the wiring pattern are simply in contact when not pressed.

[0094] Reference Figure 6 (a)~ Figure 6 (c) The operation of the pressure sensor 1A described above will be explained. Figure 6 (a)~ Figure 6 (c) is a cross-sectional view showing the operation of the pressure sensor in this embodiment. Specifically, Figure 6 (a) is a diagram showing the state in which the connector begins to contact the comb pattern. Figure 6 (b) indicates that it is related to Figure 6 (a) is a diagram comparing the state with the increased load applied. Figure 6 (c) indicates that it is related to Figure 6 (b) is a diagram of the state with a further increase in load compared to the state with the load applied.

[0095] When the pressure sensor 1A is pressed by the pressing element (not shown), as Figure 6 As shown in (a), the substrate 21 of the upper film substrate 20 is recessed from the center of the opening 31 of the spacer 30. Therefore, the connector 22 disposed on the lower surface of the substrate 21 first contacts the front end 161 of the wiring pattern 16 of the lower film substrate 10, and this connector 22 only contacts the innermost comb pattern 15K. At this time, as described above, a power supply voltage (e.g., 5V) is applied to one wiring pattern 12 connected to the resistor 14, and in contrast, another wiring pattern 13 connected to the resistor 14 is grounded, with the innermost comb pattern 15K directly connected to this other wiring pattern 13. Therefore, the wiring pattern 16 detects a voltage at approximately the same potential as ground, and the potential difference (e.g., 5V) between the power supply voltage and the detected voltage of the wiring pattern 16 is output using a multimeter (not shown) connected to the wiring patterns 12 and 16.

[0096] Although not specifically illustrated here, the pressing member is, for example, a component made of resin material, etc., and is supported above the upper film substrate 20 in a manner that allows it to approach or move away from the upper surface of the substrate 21 of the upper film substrate 20. In this embodiment, the pressing member is configured such that the center of the pressing member substantially coincides with the center of the opening 31 of the spacer 30 (the center CP of the opposing region 111 of the substrate 11 of the lower film substrate 10), and is configured such that when the upper film substrate 20 is pressed by the pressing member, the connecting body 22 first contacts the front end 161 of the wiring pattern 16 and the innermost comb pattern 15K. As a specific example of such a pressing member, the operation key of a controller can be exemplified. In addition, the pressing member can also be the pressing member 40 described later (see Figure 12 It has a downward-protruding part. Alternatively, the pressing element could be the operator's finger.

[0097] Furthermore, as the pressing force (applied load) of the pressing member increases, the recessed portion of the substrate 21 of the upper film substrate 20 expands, and the connection object of the connector 22 extends to the outermost comb pattern 15J-15B. As a result, the distance between one end 141 of the resistor 14 and the connection position of the connection object becomes shorter, and consequently, the resistance value between the wiring patterns 12 and 16 decreases.

[0098] Thus, in this embodiment, by changing the outermost comb pattern in the comb pattern that contacts the connector 22, the connection position of the resistor 14 to the wiring pattern 16 via the connector 22 and the comb patterns 15A to 15K changes, and therefore the distance between one end 141 of the resistor 14 and this connection position changes. That is, in the pressure sensor 1A of this embodiment, the resistance length (resistance value) of the resistor 14 changes according to the pressing force of the pressing member, and therefore the voltage detected by the wiring pattern 16 changes according to the pressing force of the pressing member.

[0099] If we give an example, then such as Figure 6 As shown in (b), with Figure 6 Compared to state (a), the applied load increases, and the connector 22 contacts not only the wiring pattern 16 and the comb pattern 15K, but also the comb patterns 15J to 15F. The wiring pattern 16 detects a voltage of approximately half the potential of the power supply voltage, and outputs the potential difference (e.g., 2.5V) between the power supply voltage and the detection voltage of the wiring pattern 16 using a multimeter or the like.

[0100] Furthermore, in this embodiment, the resistance value between wiring patterns 12 and 16 varies depending on the connection position of the comb patterns 15B to 15J that connect the resistor 14 to the wiring pattern 16 via the connector 22, thus the output of the pressure sensor 1A is stepped. Therefore, the more comb patterns there are, the narrower the spacing between them, and the higher the resolution of the pressure sensor 1A's output.

[0101] If with Figure 6 If, compared to state (b), the applied load is further increased and the pressure sensor 1A is sufficiently pressed in, then as... Figure 6 As shown in (c), in addition to contacting the wiring pattern 16 and the comb patterns 15K-15B, the connector 22 also contacts the outermost comb pattern 15A. At this time, the outermost comb pattern 15A is directly connected to a wiring pattern 12 connected to the power supply voltage. Therefore, the wiring pattern 16 detects a voltage at approximately the same potential as the power supply voltage, and outputs the potential difference (e.g., 0V) between the power supply voltage and the detected voltage of the wiring pattern 16 using a multimeter or the like.

[0102] When the pressing of the pressing member is released, the opposite action is performed. That is, as the applied load decreases, the recessed portion of the substrate 21 of the upper film substrate 20 becomes smaller, and the connection object of the connector 22 narrows to the inner comb pattern 15B-15J. As a result, the distance between one end 141 of the resistor 14 and the connection position of the connection object becomes longer, and therefore, the resistance value between the wiring patterns 12 and 16 increases.

[0103] Furthermore, the method for obtaining the output of the pressure sensor 1A is not particularly limited to the method described above. For example, a resistance meter can also be used to measure the resistance value between wiring patterns 12 and 16.

[0104] As described above, in this embodiment, the resistor 14 is positioned so as not to overlap with the connector 22 when viewed from above. With the pressing of the pressing member, the connector 22 is electrically connected to the comb patterns 15B-15J connected to the resistor 14. Therefore, in this embodiment, the resistor 14 does not contact the connector 22, thus enabling stable and good output characteristics of the pressure sensor 1A.

[0105] In particular, the resistance value of a resistive element made of carbon with high resistivity tends to become less stable as the distance between the resistive elements increases. Furthermore, the resistance value of this resistive element also tends to be unstable due to the reproducibility of the contact. Therefore, by utilizing variations in the contact area between the connector and the resistive element, it is difficult to make the output characteristics (applied load - resistance value) of this pressure sensor approach an ideal (linear) output. Additionally, there is a tendency for the output to deviate with each press.

[0106] In contrast, in this embodiment, low-resistance comb patterns 15B-15J are arranged concentrically in the opposing region 111 with the front end 161 of the wiring pattern 16 as the center. These comb patterns 15B-15J are connected to the high-resistance resistor 14 at intervals. The position of the comb patterns 15B-15J, connected to the wiring pattern 16 via the connector 22, changes according to the applied load, thereby changing the resistance length (resistance value) of the resistor 14. Thus, in this embodiment, instead of utilizing the contact area between the connector and the resistor, the resistance length of the resistor 14 is used to detect the resistance value corresponding to the applied load, thereby enabling the stable and efficient output characteristics of the pressure sensor 1A.

[0107] Furthermore, in this embodiment, the outermost comb pattern 15A is directly connected to a wiring pattern 12, and the innermost comb pattern 15K is directly connected to another wiring pattern 13. Therefore, the maximum value of the output of the pressure sensor 1A can be made equal to the power supply voltage, and the minimum value of the output can be made equal to ground.

[0108] Furthermore, in this embodiment, since all wiring patterns 12, 13, and 16 connected to the outside are provided on the upper surface of the same substrate 11, the connector can be installed only on the upper surface, thus simplifying the structure of the pressure sensor 1A.

[0109] <<Second Implementation Method>>

[0110] Figure 7 This is a top view showing the pressure-sensitive sensor according to the second embodiment of the present invention. Figure 8 It is along Figure 7 A cross-sectional view of line VIII-VIII. Figure 9 This is a top view showing the lower film substrate in this embodiment. Figure 10 This is a bottom view showing the spacer and the upper film substrate in this embodiment.

[0111] like Figures 7-10 As shown, the pressure sensor 1B of this embodiment differs from the pressure sensor 1A of the first embodiment in that: (1) the wiring pattern 16 is provided on the upper substrate 21 and is directly connected to the connector 22; and (2) it does not have an arc portion 152, and the straight comb-like patterns 15A to 15K penetrate the opposing region 111. Other than this, the structure is the same as that of the first embodiment. Hereinafter, regarding the pressure sensor 1B of the second embodiment, only the differences from the first embodiment will be described, and the same reference numerals will be used for structures that are the same as those in the first embodiment, and the descriptions will be omitted.

[0112] like Figure 8 and Figure 10As shown, in this embodiment, the wiring pattern 16 is formed on the lower surface of the substrate 21 of the upper film substrate 20. Furthermore, the wiring pattern 16 is directly connected to the connector 22 by being integrally formed with it. Alternatively, when a metal film is used as the substrate 21, the substrate 21 can function as both the connector 22 and the wiring pattern 16.

[0113] In addition, such as Figure 7 as well as Figure 9 As shown, the multiple comb patterns 15A to 15K do not have arcuate portions 152, but are only composed of straight portions 151, which penetrate the opposing region 111. In this embodiment, the straight portions 151 of the multiple comb patterns 15A to 15K are arranged in half of the lower side (the -Y direction side in the figure) of the opposing region 111, and are spaced apart and substantially parallel to each other from the center CP of the opposing region 111 outward.

[0114] Furthermore, in this embodiment, the pressing start position of the pressing member can also be set at any position within the opposing region 111 other than the center CP. In this case, the straight portions of the comb pattern are spaced apart from the pressing start position outside the opposing region 111 and are arranged substantially parallel to each other.

[0115] In the pressure sensor 1B of this embodiment, similarly to the first embodiment, the connection position of the resistor 14 via the connector 22 and the comb pattern 15A to 15K to the wiring pattern 16 changes depending on the magnitude of the pressing force (applied load) of the pressing member (not shown), and thus the magnitude of the resistance length (resistance value) of the resistor 14 changes.

[0116] In this embodiment, similarly to the first embodiment, the resistor 14 is positioned so as not to overlap with the connector 22 when viewed from above. As the pressing member is pressed, the connector 22 is electrically connected to the comb patterns 15B-15J connected to the resistor 14. Therefore, in this embodiment, the resistor 14 does not contact the connector 22, thus ensuring stable and good output characteristics of the pressure sensor 1B.

[0117] Furthermore, in this embodiment, the comb patterns 15A and 15K at both ends are directly connected to the wiring patterns 12 and 13, respectively. Therefore, the maximum output value of the pressure sensor 1B can be made equal to the power supply voltage.

[0118] <<Third Implementation Method>>

[0119] Figure 11 This is a cross-sectional view showing the pressure-sensitive sensor according to the third embodiment of the present invention.

[0120] like Figure 11 As shown, the pressure sensor 1C of this embodiment differs from the pressure sensor 1A of the first embodiment in that: (1) a pressing member 40 is provided instead of the upper substrate 21; and (2) a supporting member 50 is provided instead of the spacer 30, but the structure is otherwise the same as that of the first embodiment. Hereinafter, regarding the pressure sensor 1C of the third embodiment, only the differences from the first embodiment will be described, and the same reference numerals will be used for structures that are the same as those in the first embodiment, and the descriptions will be omitted.

[0121] The pressing member 40 is made of an electrically insulating elastic material such as silicone rubber, and has a conical portion 41 that protrudes downwards at its lower part. Furthermore, in this embodiment, instead of the substrate 21, a connector 22 is formed on the lower surface of the conical portion 41 of the pressing member 40. In this embodiment, the opposing region 111 of the substrate 11 of the lower film substrate 10 is the region in the substrate 11 that opposes the connector 22.

[0122] Furthermore, in this embodiment, the pressing member 40 has a circular planar shape corresponding to the arcuate portion 152 of the comb tooth patterns 15A to 15K, but the planar shape of the pressing member 40 is not particularly limited to this. For example, the planar shape of the pressing member 40 may also have a strip-shaped planar shape corresponding to a portion of the arcuate portion 152 of the comb tooth patterns 15A to 15K. In this case, the pressing member 40 only needs to partially overlap with all of the comb tooth patterns 15A to 15K.

[0123] Alternatively, the pressing member 40 may be made of a conductive elastic material such as conductive rubber, thereby making the pressing member 40 itself conductive. In this case, the pressing member 40 may function as a connector 22, or a connector 22 may be formed separately from the pressing member 40 in the tapered portion 41. Alternatively, only the tapered portion 41 of the pressing member 40 may be conductive.

[0124] The support member 50 is also made of an elastic material such as silicone rubber and is disposed around the opposing region 111 of the substrate 11 of the lower film substrate 10. The pressing member 40 is supported on the support member 50 with its tapered portion 41 facing the detection portion 155 of the comb pattern 15A to 15K and the front end portion 161 of the wiring pattern 16. In this embodiment, the center CP of the opposing region 111, when viewed from above, overlaps with the front end portion 161 of the wiring pattern 16 and is substantially consistent with the center of the tapered portion 41 of the pressing member 40.

[0125] Furthermore, in this embodiment, a two-end support structure is adopted in which support members 50 are connected to both sides of the pressing member 40, but it is not particularly limited to this. A one-end support structure in which only one side of the pressing member 40 is connected to the support member 50 may also be adopted.

[0126] The connecting body 22, pressing member 40, and supporting member 50 in this embodiment are equivalent to an example of the "pressing unit" in this invention, and the pressing member 40 in this embodiment is equivalent to an example of the "pressing part" in this invention.

[0127] Figure 12 This is a cross-sectional view showing a modified example of the pressure sensor of this embodiment.

[0128] It is possible Figure 12 As shown in the pressure-sensitive sensor 1D, the support member 50 is configured to move vertically relative to the substrate 11, and a connector 22 is provided on the lower surface of the support member 50. More specifically, the front end of the foot 51 of the support member 50 is inserted into a through hole in the substrate 11, and the support member 50 is supported on the substrate 11 by an elastic body (not shown) such as a coil spring. In addition, the connector 22 has a strip-shaped planar shape corresponding to a portion of the detection portion 155 of the comb pattern 15A to 15K, and is composed of a generally V-shaped metal sheet protruding downward from the center. The connector 22 is fixed to the support member 50 at one end.

[0129] Furthermore, the planar shape of the connector 22 is not particularly limited to the shape described above; for example, it can be a circular planar shape corresponding to the shape of the detection section 155 of the comb pattern 15A-15K. Furthermore, the cross-sectional shape of the connector 22 is not particularly limited to the shape described above. For example, in... Figure 12 In this configuration, the connector 22 is fixed to the support member 50 at one end. However, as long as the position of the connector 22 does not shift relative to the support member 50, both ends may not be fixed to the support member 50. Additionally, the support member 50 has a two-end support structure with feet 51 at both ends, but is not particularly limited to this. The support member 50 may also have a one-end support structure with a foot 51 at only one end.

[0130] Furthermore, in this example, the connector 22 and the support member 50 are equivalent to an example of the "pressing unit" in the present invention, and the portion of the support member 50 opposite to the connector 22 is equivalent to an example of the "pressing part" in the present invention.

[0131] return Figure 11In the pressure sensor 1C of this embodiment, similarly to the first embodiment, the connection position of the resistor 14 via the connector 22 and the comb pattern 15A to 15K to the wiring pattern 16 changes depending on the magnitude of the pressing force (applied load) of the pressing member 40, and thus the resistance length (resistance value) of the resistor 14 changes.

[0132] In this embodiment, similar to the first embodiment, the resistor 14 is positioned so as not to overlap with the connector 22 when viewed from above. As the pressing member 40 presses, the connector 22 is electrically connected to the comb patterns 15B-15J connected to the resistor 14. Therefore, in this embodiment, the resistor 14 does not contact the connector 22, thus ensuring stable and good output characteristics of the pressure sensor 1C.

[0133] Furthermore, the embodiments described above are provided for ease of understanding of the present invention and are not intended to limit the present invention. Therefore, the essence of the elements disclosed in the above embodiments is to also include all design modifications and equivalents that fall within the technical scope of the present invention.

[0134] For example, in the first embodiment described above, the wiring pattern 16 is formed on the upper surface of the substrate 11 of the lower film substrate 10, but it is not particularly limited to this. Specifically, in Figures 1-4 In the manner shown, similar to the second embodiment, a wiring pattern 16 can also be formed on the lower surface of the substrate 21 of the upper film substrate 20, and this wiring pattern 16 can be directly connected to the connector 22. Similarly, in Figure 5 In the modified example shown, a wiring pattern 16 may also be formed on the lower surface of the substrate 21 of the upper film substrate 20, and the wiring pattern 16 may be directly connected to the connector 22.

[0135] In addition, in the second embodiment, the wiring pattern 16 is formed on the lower surface of the substrate 21 of the upper film substrate 20, and the wiring pattern 16 is directly connected to the connector 22, but it is not particularly limited to this. Specifically, in Figures 7-10 In the manner shown, similar to the first embodiment, a wiring pattern 16 may also be formed on the upper surface of the substrate 11 of the lower film substrate 10.

[0136] Furthermore, in the third embodiment, the wiring pattern 16 is also formed on the upper surface of the substrate 11 of the lower film substrate 10, but it is not particularly limited to this. Specifically, in Figure 11 as well as Figure 12 In the manner shown, a wiring pattern 16 can also be formed on the support member 50 and the wiring pattern 16 can be directly connected to the connector 22.

[0137] In addition, in the first embodiment described above, the wiring pattern 12 is connected to the power supply and the wiring pattern 13 is grounded to obtain the detection voltage of the wiring pattern 16, thereby detecting the resistance value of the resistor 14. However, the circuit structure used to detect the resistance value of the resistor 14 is not particularly limited to this.

[0138] For example, although not specifically illustrated, the power supply can be connected to wiring patterns 12 and 16 without wiring pattern 13. Or, as... Figure 13 As shown, the wiring pattern 13 can also be replaced by covering the other end 142 of the resistor 14 with the wiring pattern 16. In these cases, the resistance value between the wiring patterns 12 and 16 also varies depending on the pressing force of the pressing element. Figure 13 This is a cross-sectional view of the lower membrane substrate of the pressure-sensitive sensor according to the fourth embodiment of the present invention.

[0139] Alternatively, the pressure sensor 1A described above can be used to construct a seating sensor. This seating sensor is a sensor that detects the seating position of an occupant in a seat installed in a vehicle such as an automobile. Furthermore, the pressure sensors 1B to 1D described in the second to fourth embodiments described above can be used instead of pressure sensor 1A to construct the seating sensor.

[0140] Specifically, the seating sensor is constructed by embedding a pressure-sensitive sensor 1A in the seating area of ​​the car seat. Furthermore, the number of pressure-sensitive sensors 1A embedded in the seating area is not particularly limited; there can be one or more. This pressure-sensitive sensor 1A is connected, for example, to the car's ECU (Electronic Control Unit) and outputs a voltage value corresponding to the resistance length (resistance value) of the resistor 14 corresponding to the occupant's weight to the ECU.

[0141] With the occupant seated, at least the front end 161 of the wiring pattern 16 and the innermost comb pattern 15K are connected via the connector 22. Therefore, the ECU determines whether the occupant is seated by comparing the output value of the pressure sensor A1 with a predetermined threshold.

[0142] Furthermore, in this pressure sensor A, since the outermost comb pattern among the comb patterns 15A to 15K that contact the connector 22 varies according to the weight of the occupant sitting in the seat, the resistance length (resistance value) of the resistor 14 also varies according to the occupant's weight. Therefore, the ECU classifies the occupant's weight into weight zones corresponding to each of the specified ranges by comparing the output value of the pressure sensor 1A with multiple specified ranges.

[0143] Although not specifically limited, these ECU-based judgments are used, for example, in SBR (Seat Belt Remitter) systems.

[0144] Furthermore, the applications of the aforementioned pressure sensors 1A to 1D are not limited to seating sensors. For example, for SRS (Supplemental Restraint System) systems, pressure sensors 1A to 1D can be embedded in the seat back of a car seat to detect the occupant's posture and physique. Alternatively, the aforementioned pressure sensors 1A to 1D can be used for applications other than automobiles.

[0145] Explanation of reference numerals in the attached figures

[0146] 1A~1D… Pressure-sensitive sensor; 10… Lower film substrate; 11… Substrate; 111… Opposing area; 12… Wiring pattern; 121… End; 13… Wiring pattern; 131… End; 14…

[0147] Resistor element; 141, 142… ends; 15A~15K… comb pattern; 151… straight section; 152…

[0148] Arc portion; 153…bending portion; 155…detection portion; 156…lead-out portion; 16…wiring pattern; 161…front end portion (expanded diameter portion); 163…connecting line; 17…dummy pattern; 20…upper diaphragm substrate; 21…substrate; 22…connector; 30…spacer; 31…opening; 40…pressing member; 41…conical portion; 50…supporting member; 51…foot.

Claims

1. A pressure-sensitive sensor comprising: a first substrate; a resistor provided on the first substrate; a first wiring pattern provided on the first substrate and connected to the resistor; a plurality of first comb-tooth patterns provided on the first substrate and each independently connected to the resistor; a pressing unit opposed to the first comb-tooth patterns and having a pressing portion capable of approaching the first substrate and a connecting body held by the pressing portion and electrically connected to the first comb-tooth patterns by pressing of the pressing portion; and a second wiring pattern provided on the first substrate and electrically connected to the connecting body by pressing of the pressing portion, or included in the pressing unit and connected to the connecting body, a resistivity of a material constituting the resistor is higher than each of a resistivity of a material constituting the first wiring pattern, a resistivity of a material constituting the first comb-tooth patterns, a resistivity of a material constituting the connecting body, and a resistivity of a material constituting the second wiring pattern, the resistor is disposed at a position not overlapping the connecting body in plan view, and a resistance value between the first wiring pattern and the second wiring pattern changes according to a load applied to the pressing portion.

2. The pressure-sensitive sensor according to claim 1, wherein the first wiring pattern is connected to one end of the resistor, and the plurality of first comb-tooth patterns are connected between the one end and the other end of the resistor in a state of being spaced apart from each other along a length direction of the resistor.

3. The pressure-sensitive sensor according to claim 1 or 2, wherein the plurality of first comb-tooth patterns are disposed in the opposed region of the first substrate opposed to the connecting body in a state of being spaced apart from each other and substantially parallel to each other.

4. The pressure-sensitive sensor according to claim 3, wherein the plurality of first comb-tooth patterns are arranged in the opposed region from an inner side toward an outer side in a state of being spaced apart from each other.

5. The pressure-sensitive sensor according to claim 1 or 2, wherein the plurality of first comb-tooth patterns are disposed in the opposed region of the first substrate opposed to the connecting body in a concentric circular shape with a pressing start position as a center.

6. The pressure-sensitive sensor according to claim 1 or 2, wherein the plurality of first comb-tooth patterns are provided on the first substrate in such a manner that the closer the connection position of the first comb-tooth patterns to the other end side of the resistor, the closer the first comb-tooth patterns are located to the pressing start position in the opposed region of the first substrate opposed to the connecting body.

7. The pressure-sensitive sensor according to claim 1 or 2, further comprising: a third wiring pattern provided on the first substrate and connected to the other end of the resistor; a second comb-tooth pattern provided on the first substrate in a manner opposed to the connecting body and connected to the first wiring pattern; and a third comb-tooth pattern provided on the first substrate in a manner opposed to the connecting body and connected to the third wiring pattern. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The material constituting the resistance body has a higher resistivity than each of a resistivity of a material constituting the third wiring pattern, a resistivity of a material constituting the second comb-tooth pattern, and a resistivity of a material constituting the third comb-tooth pattern, The first comb-tooth pattern, the second comb-tooth pattern, and the third comb-tooth pattern are arranged in parallel at intervals in an area of the first substrate opposite the connection body.

8. The pressure-sensitive sensor according to claim 1 or 2, wherein The pressing unit includes: a second substrate having the connection body; and a spacer between the first substrate and the second substrate, The spacer has an opening opposing the connection body and the first comb-tooth pattern.

9. The pressure-sensitive sensor according to claim 1 or 2, wherein The second wiring pattern is provided on the first substrate in a manner opposing the connection body.

10. The pressure-sensitive sensor according to claim 1 or 2, wherein The second wiring pattern is connected to the resistance body.

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