WO2017188130A1 - Pressure-sensitive detection method, pressure-sensitive sensor, pressure-sensitive detection device, and pressure-sensitive detection system - Google Patents

Abstract

In this pressure-sensitive detection method and this pressure-sensitive sensor: one or multiple piezoelectric layers each having a pressure input surface part are provided in an area for detecting a pressure input; at least one electrode of one or multiple pairs of electrodes, which are arranged across the piezoelectric layers, is used as a pattern electrode provided with a continuous electrode part or multiple electrode parts narrower than the pressure input surface part; the pattern electrode receives a pressure input; and a pressure-sensitive output is taken out. Accordingly, an insensitive region can be reduced from the pressure input surface part, whereby detection efficiency can be enhanced. Furthermore, there is no need of a contact point or no need to keep a distance between contact points by using elasticity. Thus, the pressure-sensitive sensor can be reduced in size and weight, no contact point deteriorates over time, stable pressure-sensitive detection can be performed over a long period of time, and reduction in maintenance cost can be achieved.

Description

Pressure-sensitive detection method, pressure-sensitive sensor, pressure-sensitive detection device, and pressure-sensitive detection system

The present invention relates to a sensor technology for detecting pressure received from a person or an object with a piezoelectric element.

In the detection of a person or an object, the weight of the person or the object is converted into an electrical signal, and a pressure sensor is used for the presence or absence of the person or the object, the passage or gathering of the electrical signal.

It is known that this pressure sensor includes a pressure-sensitive conductive rubber and an electrode whose electrical resistance value and impedance change when pressurized, and detects pressure applied from the outside (Patent Document 1).

JP 63-32330 A

By the way, in the detection mat provided with the conventional pressure sensor, the spacer is held between the upper and lower electrodes, the spacer is compressed by weighting, and the passage of a person or an object is determined when the pressure-sensitive conductive rubber and the electrode are electrically connected. It is possible. The detection structure using such pressure-sensitive conductive rubber or spacer has the following problems.

(1) Even if the contact range is expanded by adopting shoreline sensing, there is a dead zone in the sensing range, and the detection efficiency is low.

(2) Only opening / closing output can be obtained by opening / closing between the electrodes, and this opening / closing output is only generated by pressurization input above a certain pressure.

(3) Conductive rubber and spacers are subject to deterioration over time and elastic fatigue, and stable operation cannot be obtained over a long period of time, resulting in malfunction and lack of reliability.

(4) Conductive rubber and spacer elasticity keeps the distance between electrodes, conduction between contacts by compression, and return of distance by compression release. Is hindered.

Regarding such demands and issues, Patent Document 1 does not disclose or suggest the request, and does not disclose or suggest the configuration or the like for solving it.

In view of the above problems, an object of the present invention is to obtain a detection output corresponding to a pressure level, to reduce the size and weight of the sensor, increase the detection efficiency, and obtain a highly reliable pressure-sensitive characteristic. There is.

In order to achieve the above object, according to one aspect of the pressure-sensitive detection method of the present invention, a single or a plurality of piezoelectric layers having a pressure input surface portion are installed in a pressure input detection area, and the piezoelectric layer is sandwiched therebetween. At least one electrode of a single or a plurality of electrode pairs arranged in a pattern electrode including a continuous electrode portion or a plurality of electrode portions narrower than the pressure input surface portion, and receives pressure input to the pattern electrode, A pressure sensitive output is taken out from the pattern electrode.

In order to achieve the above object, according to one aspect of the pressure-sensitive sensor of the present invention, a single or a plurality of piezoelectric layers having a pressure input surface portion in a pressure input detection area and the piezoelectric layer are disposed between the piezoelectric layers. A single or a plurality of electrode pairs, and a pattern electrode that is provided on at least one electrode of the electrode pair, includes a plurality of electrode portions narrower than the pressure input surface portion, and receives pressure input. A pressure-sensitive output obtained by input is taken out from the plurality of electrode portions included in the pattern electrode.

In the pressure-sensitive sensor, the pattern electrode may be a plurality of electrodes that extract one or more of pressure-sensitive outputs indicating the level, position, direction, or range of the pressure input, and outputs indicating a distribution of a plurality of pressure inputs. May include parts.

In the pressure-sensitive sensor, the pattern electrode may include a plurality of electrode portions disposed on any one or more of a plane, a back surface, and a side surface of the piezoelectric layer.

In the pressure-sensitive sensor, the pattern electrode includes a single or a plurality of electrode portions that are continuously bent on the pressure input surface of the piezoelectric layer, a plurality of electrode portions obtained by dividing the single electrode portion into two or more, A plurality of electrode portions arranged in the X-axis direction, the Y-axis direction, or the Z-axis direction on the pressure input surface of the piezoelectric layer, or a plurality of electrode portions branched in any plurality of directions on the pressure input surface Either may be included.

The pressure sensor may further include a shield layer that shields at least the electrode pair.

The pressure sensor may further include a viscoelastic protective layer that covers the piezoelectric layer, and a non-slip layer that is installed on an outer surface of the viscoelastic protective layer.

The pressure-sensitive sensor may further include a rigid layer that is interposed between the piezoelectric layer and the support means and supports the laminate including the piezoelectric layer.

In order to achieve the above object, according to one aspect of the pressure-sensitive detection device of the present invention, the presence of a person or an object, a position, a passage, or a set of the pressure-sensitive sensor and the pressure-sensitive output of the pressure-sensitive sensor are used. Determination means for determining one of them.

In order to achieve the above object, according to one aspect of the pressure-sensitive detection device of the present invention, the pressure-sensitive sensor and the signal conversion unit that converts the sensor output of the pressure-sensitive sensor into a sound signal or an optical signal are provided.

In order to achieve the above object, according to one aspect of the pressure-sensitive detection device of the present invention, the control signal for starting and stopping the operation of the control target device according to the pressure-sensitive sensor and the sensor output level of the pressure-sensitive sensor. And a control unit for outputting.

In order to achieve the above object, according to one aspect of the pressure-sensitive detection system of the present invention, the pressure-sensitive sensor or the pressure-sensitive detection device and the pressure-sensitive sensor or the pressure-sensitive detection device are installed. An area where an object passes or gathers, and processing means for performing processing including passage or gathering of persons or objects in the area from the sensor output of the pressure sensor included in the pressure sensor or the pressure sensing device; Presentation means connected to the processing means by wire or wirelessly and presenting the processing result of the processing means.

According to the pressure-sensitive detection method, pressure-sensitive sensor, pressure-sensitive detection device, and pressure-sensitive detection system of the present invention, any of the following effects can be obtained.

(1) The detection efficiency can be increased by reducing the dead area from the pressure input surface.

(2) There is no need to maintain the contact between the contacts and the elasticity between the contacts, the pressure sensor can be reduced in size and weight, and there is no deterioration of the contacts over time, and stable pressure sensing can be detected over a long period of time. And maintenance costs can be reduced.

(3) A pressure-sensitive output at a level corresponding to the pressure input can be obtained, and the degree of freedom of processing such as processing using the pressure-sensitive output level can be expanded.

Other objects, features, and advantages of the present invention will become clearer with reference to the accompanying drawings and each embodiment.

It is a figure for demonstrating the pressure-sensitive detection method and pressure sensor which concern on one embodiment. A is a diagram showing a pressure-sensitive operation when a pressure input M is applied to either one of the electrode unit 16a-1 or the electrode unit 16a-2, and B is a diagram illustrating both the electrode unit 16a-1 and the electrode unit 16a-2. FIG. 7 is a diagram showing a pressure-sensitive operation when a pressure input M is applied to the electrode portion C, and FIG. C is a diagram showing a pressure-sensitive operation when the pressure input M applied to the electrode portions 16a-1 and 16a-2 is biased. . A is a figure which abbreviate | omits and shows a part of pressure sensor which concerns on Example 1, B is a figure which shows a part of lamination | stacking cross section of a pressure sensor. It is a figure which shows the pressure sensitive operation | movement of a pressure sensor. A is a plan view showing a step device according to Embodiment 2, and B is a view showing a VB-VB cross section of A. FIG. A is a figure which shows the building provided with the pressure-sensitive detection system which concerns on Example 3, B is a figure which shows a pressure-sensitive detection system. It is a figure which shows a pressure sensitive detection apparatus. It is a figure which shows a pressure sensitive operation. FIG. 10 is a diagram illustrating a mat sensor according to a fourth embodiment. It is a figure which shows a pressure sensitive operation and signal processing. 10 is a diagram illustrating an example of an electrode unit according to Example 5. FIG. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows an example of another electrode part. It is a figure which shows the pressure-sensitive detection apparatus which concerns on Example 6. FIG.

<Pressure detection method and pressure sensor>

FIG. 1A shows a pressure-sensitive detection method and a pressure-sensitive sensor according to an embodiment.

The pressure sensor 2 is provided with a detection area 4 and receives a pressure input M in the detection area 4. This pressurizing input M is a pressure applied from a person or an object, and may be a pressure from the foot surface for a person, for example, or a pressure from the bottom surface for an object. The detection area 4 may be set in an area where a person or an object passes.

The pressure sensor 2 is provided with a piezoelectric layer 6. The piezoelectric layer 6 includes a back support layer 8 on the back side, is supported by the area side support surface 10 of the detection area, and includes a pressure transmission layer 12 that receives the pressure input M on the top side. The piezoelectric layer 6 is, for example, a piezoelectric sheet, and a pressure input M is applied to the piezoelectric layer 6 through the pressure transmission layer 12 and converted into a piezoelectric output by the piezoelectric conversion function of the piezoelectric layer 6.

As shown in FIG. 1B, the piezoelectric layer 6 includes a pressure input surface portion 14a on the upper surface side and a support surface portion 14b on the lower surface side. That is, the pressure input surface portion 14a is a pressure receiving surface for the pressure input M, and the support surface portion 14b is a support surface for receiving the pressure input M on the back side.

The piezoelectric layer 6 includes an electrode pair 16 as an example of a single or a plurality of pattern electrode pairs. The electrode pair 16 includes electrode portions 16a-1 and 16a-2 on the electrode 16a on the pressure input surface portion 14a side, and electrode portions 16b-1 and 16b-2 on the electrode 16b on the support surface portion 14b side. That is, the electrode portions 16a-1 and 16a-2 have an electrode surface narrower than the pressure input surface portion 14a, and the electrode portions 16b-1 and 16b-2 are the same.

As shown in FIG. 1C, a narrow insulation interval 18 is set between the adjacent electrode portions 16a-1 and 16a-2, and also between the electrode portions 16b-1 and 16b-2. A similar insulation interval 18 is set.

Thus, the electrode pair 16 includes a plurality of electrode portions 16a-1, 16a-2 or electrode portions 16b-1, 16b-2 to form a patterned electrode having a plurality of electrode surfaces. In this example, the electrode portions 16b-1 and 16b-2 also form pattern electrodes, but the pattern electrode is formed only by one of the electrode portions 16a-1 and 16a-2, and the electrode portions 16b-1 and 16b- 2 may be a single electrode part.

Therefore, when the pressure input M is received by the pressure-sensitive sensor 2 having such an electrode pair 16, when the pressure input M is applied to either the electrode portion 16a-1 or the electrode portion 16a-2, the electrode portion 16a When the pressure input M is applied to both -1 and the electrode part 16a-2, there is a pattern in which the pressure input M applied to the electrode part 16a-1 and the electrode part 16a-2 is biased.

<When pressurization input M is applied to one of electrode part 16a-1 or electrode part 16a-2>

As shown by a solid line in FIG. 2A, when a pressure input M is applied to the electrode portion 16a-1, a piezoelectric output is obtained from the electrode portion 16a-1. Further, as indicated by a broken line in FIG. 2A, when a pressure input M is applied to the electrode portion 16a-2, a piezoelectric output is obtained from the electrode portion 16a-2. This can be determined by comparing and amplifying the piezoelectric outputs of the electrode portions 16a-1 and 16a-2 with a differential amplifier or the like.

<When pressure input M is applied to both electrode 16a-1 and electrode 16a-2>

As shown by the solid line in FIG. 2B, when a pressure input M is applied in common to the electrode portions 16a-1 and 16a-2, piezoelectric outputs can be obtained from both the electrode portions 16a-1 and 16a-2. If the same pressure is applied to both the electrode portions 16a-1 and 16a-2, the same piezoelectric output can be obtained from the electrode portions 16a-1 and 16a-2. This can be similarly determined by comparing the piezoelectric outputs of the electrode portions 16a-1 and 16a-2.

<When the pressure input M applied to the electrode portion 16a-1 and the electrode portion 16a-2 is biased>

As indicated by the solid line in FIG. 2C, if the pressure input M applied to the electrode portions 16a-1 and 16a-2 acts strongly on the electrode portion 16a-1 side, the piezoelectric output obtained from the electrode portion 16a-1 can be obtained. It becomes larger than the piezoelectric output obtained from the electrode portion 16a-2. Further, as indicated by a broken line in FIG. 2C, if the pressure input M applied to the electrode portions 16a-1 and 16a-2 acts strongly on the electrode portion 16a-2 side, the piezoelectric obtained from the electrode portion 16a-2 is obtained. The output becomes larger than the piezoelectric output obtained from the electrode portion 16a-1. This can be similarly determined by comparing the piezoelectric outputs of the electrode portions 16a-1 and 16a-2.

<Material of piezoelectric layer 6>

The piezoelectric layer 6 may be a piezoelectric functional layer of a single member or a laminate of a plurality of members. The piezoelectric layer 6 may be formed by laminating a double-side smoothing layer, a protective layer, an insulating layer, or the like, or may be a monomorph, a bimorph, or a laminated type. The piezoelectric layer 6 may be an organic piezoelectric layer such as a piezoelectric resin sheet or a porous resin sheet, or may be an inorganic piezoelectric material layer such as quartz, barium titanate, or lead zirconate titanate.

The piezoelectric layer 6 has a piezoelectric constant d33 of preferably 20 × 10−12 [C / N] or more, more preferably 100 × 10−, in order to achieve an excellent vibration detection function by detecting vibration in the thickness direction. A piezoelectric material of 12 [C / N] or more may be used.

For example, a porous resin sheet may be used for the piezoelectric layer 6. This porous resin sheet has the following characteristics.

A) Charge responsiveness to micro vibration pressure and detection function are high, and charge retention is possible under high temperature environment. An excellent detection function is obtained, and it is possible to reduce the weight as well as high bruising and impact resistance.

B) Arbitrary shape such as a thin film pressure sensor 2 or a large area, a curved surface shape, and a shape followability to the detection surface shape can be obtained, and the degree of freedom of the detection surface is expanded.

The porous resin sheet is preferably a sheet made of, for example, an organic material that can retain electric charge. This porous resin sheet includes a nonwoven fabric or woven fabric made of fiber, a sheet-like foam made of an organic polymer, a stretched porous membrane made of an organic polymer, a matrix resin and charge-induced hollow particles (the surface of the hollow particles). And a phase separation agent dispersed in an organic polymer is removed by using an extractant such as supercritical carbon dioxide and empty. The sheet | seat etc. which are formed by the method of forming a hole are contained. From the viewpoint of maintaining durability and deformation performance, a nonwoven fabric or a woven fabric using a polymer fiber is preferable.

The porous resin sheet may contain one or more inorganic fillers. Thereby, the charge retention amount is high, and excellent piezoelectric characteristics can be obtained. If an inorganic filler is used, a sheet having a high piezoelectricity can be obtained. The inorganic filler preferably has a higher dielectric constant than the polymer, and may have a relative dielectric constant ε = 10 to 10,000. Inorganic fillers include titanium oxide, aluminum oxide, barium titanate, lead zirconate titanate, zirconium oxide, cerium oxide, nickel oxide, tin oxide and the like.

The thickness of the porous resin sheet may be, for example, 10 [μm] to 1 [mm], and more preferably 50 [μm] to 500 [μm]. In order to obtain high charge retention, the porosity is preferably 60% or more, more preferably 75% or more, and further preferably 80 to 99%. This porosity is
(True density of resin-apparent density of porous resin sheet) × 100 / true density of resin (1)
Is required. The apparent density may be a value calculated using the weight of the porous resin sheet and the apparent volume.

The polymer constituting the fiber preferably has a volume resistivity of 1.0 × 10 13 [Ω · cm] or more, such as polyamide resin (6-nylon, 6,6-nylon, etc.), aromatic polyamide Resins (such as aramid), polyolefin resins (such as polyethylene and polypropylene), polyester resins (such as polyethylene terephthalate), polyacrylonitrile, phenolic resins, fluorine resins (such as polytetrafluoroethylene and polyvinylidene fluoride), imides Any of resin (polyimide, polyamideimide, bismaleimide, etc.) may be used.

From the standpoint of excellent heat resistance and weather resistance, a polymer having no dipole due to the molecule and crystal structure is preferable. For example, polyolefin resin (polyethylene, polypropylene, ethylene propylene resin, etc.), polyester resin (polyethylene terephthalate, etc.), non-fluorine resin such as polyurethane resin, polystyrene resin, silicone resin, and polytetrafluoroethylene (PTFE) Fluorine resins such as tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) and tetrafluoroethylene-hexafluoropropylene copolymer (FEP) may be used.

Considering heat resistance and weather resistance, it is preferable that the continuous usable temperature is high and the glass transition point is not in the operating temperature range. For example, according to the continuous use temperature test of UL746B (UL standard), the continuous usable temperature of the polymer is preferably 50 [° C.] or higher, more preferably 100 [° C.] or higher, and further preferably 200 [° C.]. [° C.] or more. In consideration of moisture resistance, those exhibiting hydrophobicity are preferred.

For example, a polyolefin resin or a fluorine resin may be used as the polymer having these characteristics. If a polyolefin-based resin or a fluorine-based resin is used, vibration detection is possible without causing deterioration in piezoelectric characteristics even in vibration detection at temperatures below 100 [° C.] or temperatures exceeding 100 [° C.]. PTFE is preferred for the fluororesin.

PTFE has excellent heat resistance, vibration detection capability and durability, and can realize the pressure-sensitive sensor 2 capable of detecting pressure under high temperature, and can maintain vibration detection performance and structure under high temperature and high pressure environment. It is.

The fiber for forming the piezoelectric layer 6 has an average fiber diameter of preferably 0.05 to 50 [μm], more preferably 0.1 to 20 [μm], and still more preferably 0.3 to 5 [μm]. Good. If the average fiber diameter is within this range, a nonwoven fabric or woven fabric exhibiting high flexibility can be obtained. If the fiber surface area is increased, a sufficient space can be formed to hold the charge, and the fiber distribution uniformity can be increased even when the nonwoven fabric or woven fabric is formed thin.

The average fiber diameter of the fiber can be adjusted by selecting the fiber formation conditions. For example, according to the electrospinning method, the average fiber diameter of the obtained fiber is reduced by reducing the humidity, reducing the nozzle diameter, increasing the applied voltage, or increasing the voltage density during electrospinning. Tend.

Here, the average fiber diameter is measured by scanning electron microscope (SEM) observation of the fiber (group) to be measured, and randomly, for example, a plurality of SEM images observed at a magnification of 10,000 times, What is necessary is just to obtain | require 20 fibers and to obtain | require from the average value by the measurement result of these fiber diameters (major axis).

The fiber diameter variation coefficient of the fiber is preferably 0.7 or less, more preferably 0.01 to 0.5 from the value calculated by the following formula. If this fiber diameter variation coefficient is within a predetermined range, the fiber diameter of the fiber becomes uniform, and the nonwoven fabric or woven fabric obtained from this fiber has a higher porosity and a high charge retention porous resin sheet. From the viewpoint of obtaining

Fiber diameter variation coefficient = standard deviation / average fiber diameter (2)
The “standard deviation” is a standard deviation of the fiber diameters of the 20 fibers.

The fiber length of the fiber is preferably 0.1 to 1000 [mm], more preferably 0.5 to 100 [mm], and still more preferably 1 to 50 [mm].

The fiber may be produced by, for example, an electrospinning method, a melt spinning method, a melt electrospinning method, a spunbond method (melt blow method), a wet method, or a spunlace method. The fiber obtained by the electrospinning method has a small fiber diameter. In the nonwoven fabric or woven fabric using this fiber, a porous resin sheet having a high porosity, a high specific surface area, and high piezoelectricity can be obtained.

In the electrospinning method, a spinning solution containing a polymer and, if necessary, a solvent is used. A polymer may be used individually by 1 type and may use 2 or more types. The ratio of the polymer contained in the spinning solution may be, for example, 5 to 100 [wt%], preferably 5 to 80 [wt%], more preferably 10 to 70 [wt%].

The solvent is not limited as long as it can dissolve or disperse the polymer. Examples of the solvent include water, dimethylacetamide, dimethylformamide, tetrahydrofuran, methylpyrrolidone, xylene, acetone, chloroform, ethylbenzene, cyclohexane, benzene, sulfolane, methanol, ethanol, phenol, pyridine, propylene carbonate, acetonitrile, trichloroethane, hexafluoroisopropanol, Any of diethyl ether may be used. These solvents may be used alone or in a combination of two or more. The solvent contained in the spinning solution may be, for example, 0 to 90 [wt%], preferably 10 to 90 [wt%], more preferably 20 to 80 [wt%].

The spinning solution may contain additives such as an inorganic filler other than a polymer, a surfactant, a dispersant, a charge adjusting agent, a functional particle, an adhesive, a viscosity adjusting agent, and a fiber forming agent. An additive may be used individually by 1 type and 2 or more types may be sufficient as it. In the spinning solution, when the solubility of the polymer in the solvent is low, for example, when the polymer is PTFE and the solvent is water, one or more fiber forming agents are used to keep the polymer in a fiber shape during spinning. It is preferable to contain.

A polymer having high solubility in a solvent is preferable. Examples of the fiber forming agent include polyethylene oxide, polyethylene glycol, dextran, alginic acid, chitosan, starch, polypinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, cellulose, and polyvinyl alcohol. The amount of the fiber-forming agent used may be, for example, 0.1 to 15% by weight, preferably 1 to 10% by weight in the spinning solution, although it depends on the viscosity of the solvent and the solubility in the solvent.

The spinning solution may be produced by mixing a polymer, a solvent, and if necessary, an additive by a known method. If the polymer is PTFE, the spinning solution contains PTFE in an amount of 30 to 70 [wt%], preferably 35 to 60 [wt%], and a fiber forming agent in an amount of 0.1 to 10 [wt%], preferably 1 to A spinning solution containing 7 wt% and a total of 100 wt% solvent is preferred.

The applied voltage at the time of electrospinning is preferably 1 to 100 [kV], more preferably 5 to 50 [kV], and still more preferably 10 to 40 [kV].

The tip diameter (outer diameter) of the spinning nozzle used for electrospinning is preferably 0.1 to 2.0 [mm], more preferably 0.2 to 1.6 [mm].

For example, when a spinning solution is used, the applied voltage is preferably 10 to 50 [kV], more preferably 10 to 40 [kV]. The tip diameter (outer diameter) of the spinning nozzle is preferably 0.3 to 1.6 [mm].

In order to form a nonwoven fabric with fibers, for example, an electrospinning method may be used to simultaneously perform a step of producing fibers and a step of collecting fibers into a sheet to form a nonwoven fabric, or a step of producing fibers. Then, the process of accumulating the said fiber in a sheet form by a wet method and forming a nonwoven fabric may be performed.

In forming a nonwoven fabric by a wet method, for example, a method may be used in which an aqueous dispersion containing fibers is used, and the fibers are deposited (accumulated) on a mesh and formed into a sheet (paper making).

The amount of fiber used in this wet method is preferably 0.1 to 10 [wt%], more preferably 0.1 to 5 [wt%] based on the total amount of the aqueous dispersion. If the fiber is used within this range, water can be efficiently used in the process of depositing the fiber, and the fiber is well dispersed and a uniform wet nonwoven fabric can be obtained.

In order to improve the dispersion state, the aqueous dispersion is composed of a dispersing agent or an oil agent composed of a cationic, anionic or nonionic surfactant, an antifoaming agent or the like for suppressing the generation of bubbles, respectively. Seeds or two or more may be added.

The method for manufacturing a woven fabric using fibers may include a fiber manufacturing step and a woven fabric forming step of weaving the fibers obtained in this step into a sheet. A known weaving method may be used as a method for weaving the fiber into a sheet. Examples of the weaving method include water jet loom, air-jet loom, and rapier room.

If the polymer is PTFE, it is preferable to perform heat treatment after the formation of the nonwoven fabric or woven fabric. In this heat treatment, the non-woven fabric or woven fabric may be heat-treated usually under conditions of 200 to 390 [° C.] and 30 to 300 [min]. By performing this heat treatment, the solvent, fiber forming agent, etc. remaining on the nonwoven fabric or woven fabric can be removed.

As an example of a method for producing a nonwoven fabric, a case in which a production process of fibers made of PTFE by an electrospinning method is included is illustrated. As a method for producing a nonwoven fabric made of PTFE fiber, a known production method can be adopted, and examples thereof include a method described in JP-T-2012-515850. This production method includes a step of providing a spinning solution containing PTFE, a fiber forming agent, and a solvent and having a viscosity of at least 50,000 [cP], and spinning the spinning solution from a nozzle to form a fiber by electrostatic traction. A step of collecting the fibers on a collector (e.g., a take-up spool) to form a precursor, and firing the precursor to remove the solvent and fiber-forming agent to form a nonwoven fabric made of PTFE fibers. Step.

The basis weight of the nonwoven fabric and the woven fabric is preferably 100 [g / m2] or less, more preferably 0.1 to 50 [g / m2], and still more preferably 0.1 to 20 [g / m2]. The basis weight tends to increase by increasing the spinning time and increasing the number of spinning nozzles.

Nonwoven fabrics and woven fabrics have fibers accumulated or woven in sheet form. Such a non-woven fabric and a woven fabric may be either a single layer or two or more layers having different materials and fiber diameters.

The porous resin sheet is preferably subjected to polarization treatment. If the polarization treatment is performed, electric charge can be injected into the sheet, and the electric charge is concentrated in the pores in the porous resin sheet to induce polarization. In the internally polarized sheet, the charge can be taken out from the front and back surfaces of the sheet by a compressive load applied in the thickness direction of the sheet. That is, such charges cause charge transfer to the external load (electric circuit), and an electromotive force is obtained. This causes a potential difference, that is, a voltage.

As the polarization treatment method, a known method may be used. For example, a corona discharge treatment may be used in addition to a DC voltage or AC voltage application treatment.

In the corona discharge treatment, a high voltage power source and an electrode device may be used. The discharge conditions are appropriately selected according to the material and thickness of the porous resin sheet. For example, in the case of a porous resin sheet made of PTFE, the preferred treatment condition is a voltage of −0.1 to −100 [kV]. More preferably, it is -1 to -20 [kV], the current is 0.1 to 100 [mA], more preferably 1 to 80 [mA], and the distance between the electrodes is 0.1 to 100 [cm], more preferably The applied voltage may be 1 to 10 [cm], and the applied voltage may be 0.01 to 10.0 [MV / m], more preferably 0.5 to 2.0 [MV / m].

Regarding the polarization treatment, the porous resin sheet itself may be polarized. However, if the piezoelectric layer is a laminate of, for example, a porous resin sheet and an insulating layer, the laminate is formed. After that, it is preferable to perform polarization treatment after the insulating layers are stacked. The layer laminated on the porous resin sheet plays a role of preventing the electric charge held in the porous resin sheet by the polarization treatment from being attenuated by being electrically connected to the external environment. This contributes to high sensitivity of pressure detection. Moreover, it exists in the tendency which can form the new interface which can hold | maintain an electric charge between the porous resin sheet and the layer laminated | stacked on a porous resin sheet. This is considered to improve the piezoelectricity of the porous resin sheet.

<Material of electrode pair 16>

The electrode pair 16 includes at least a pair of electrodes 16a and 16b. Each electrode 16a, 16b may be an electrode layer. The constituent material of the electrode layer may be any of metal (alloy), metal oxide, metal sulfide, conductive carbide, conductive polymer, and combinations thereof. For metals (alloys), metal oxides, and metal sulfides, lithium, beryllium, magnesium, calcium, strontium, barium, boron, aluminum, gallium, indium, antimony, tin, silver, gold, copper, nickel, palladium, platinum , Chromium, molybdenum, tungsten, manganese, cobalt, alloys of these, oxides of these, composite oxides of these, sulfides of these, indium tin oxide (Indium Tin Oxide: ITO), zinc oxide (Zinc Oxide) : ZnO), silver and the like are suitable.

Conductive carbides include carbon black, graphite, activated carbon, carbon fiber, single-walled carbon nanotube (SWCNT), double-walled carbon nanotube (Double-Walled Nanotube: DWCNT), and multi-walled carbon nanotube (Multi -Walled Carbon Nanotube (MWCNT), carbon nanosheet (graphene sheet), etc. are included. Examples of the conductive polymer include poly (ethylene-3, 4-dioxythiophene), polyaniline derivatives, polypyrrole derivatives, and the like.

In this embodiment, aluminum is sputtered on the front and back surfaces of the polarization-treated piezoelectric layer 6 to form an electrode layer having a thickness of about 0.5 [μm], and the electrode pair 16 is formed using this electrode layer. Formed. The electrode 16a is an electrode layer on the pressure input surface portion 14a, and the electrode 16b is an electrode layer on the support surface portion 14b. These electrode layers are maintained in an electrically insulated state by the interposition of the piezoelectric layer 6.

<Effect of one embodiment>

(1) In this pressure sensitive sensor 2, since the electrode pair 16 includes a plurality of electrode portions 16 a-1 and 16 a-2, the insensitive area can be reduced from the pressure input surface portion 14 a and the detection effect of the pressure input M can be reduced. Is increased.

(2) In this pressure sensitive sensor 2, the pressure input M is detected by the piezoelectric layer 6 and the electrode pair 16, and it is not necessary to maintain the contact and the spacing between the contacts, and the contact does not deteriorate over time. Pressure sensing can be detected stably over a long period of time, and maintenance costs can be reduced.

(3) A piezoelectric output representing the size and position of the pressure input M can be obtained. The piezoelectric output can be used for various processes such as the position, size and distribution of the pressure input. The degree of freedom can be expanded.

(4) According to the pressure-sensitive sensor 2, a person or an object can be detected by receiving a pressure input M from the person or object entering the detection area 4.

(5) Since the saddle electrode pair 16 is a pattern electrode pair provided with a plurality of electrode portions 16a-1 and 16a-2, the input position and level of the pressure input M can be detected.

(6) Since the pattern electrode is formed by a plurality of electrode portions having a plurality of narrow electrode surfaces, a plurality of electrode portions can be arranged in the detection region, and the insensitive region can be reduced.

3A shows a cross section in which a part of the mat sensor according to the first embodiment is omitted. The same parts as those in FIG. 1 are denoted by the same reference numerals.

The mat sensor 20 is an example of the pressure-sensitive sensor 2 described above. The mat sensor 20 includes a pressure receiving layer 22, a piezoelectric laminated body 24, and a back support layer 26 from the upper surface side to the rear surface side. These laminated bodies are used as a main body, and a sealing layer 28 is integrally provided. . The laminated structure of the pressure-receiving layer 22, the piezoelectric laminate 24, the back support layer 26, and the sealing layer 28 may be formed by bonding, or may be any of an integrally formed body with an elastomer.

The pressure receiving layer 22 is an example of the pressure transmission layer 12 described above, and includes, for example, an elastic layer 22-1 as a main layer and a nonslip layer 22-2 on the upper surface side as a pressure receiving surface member. The elastic layer 22-1 is an example of a viscoelastic protective layer that covers the piezoelectric layer 6. The elastic layer 22-1 includes, for example, a thermosetting polymer (epoxy resin, thermosetting rubber, polyurethane, phenol resin, imide resin, silicone resin, etc.) or a thermoplastic polymer (acrylic resin, viscoelastic material). (Polyolefin resin, fluororesin, etc.) sheet. A conventionally known anti-slip layer may be used as the anti-slip layer 22-2, which constitutes the tread surface of the mat sensor 20 and applies friction to the bottom surface of a pedestrian shoe sole or the like as a friction material.

The piezoelectric laminated body 24 is composed of, for example, the piezoelectric layer 6 and the electrode pair 16. In this embodiment, the piezoelectric laminated body 24 includes the electromagnetic shield 30 to form a single laminated body. For example, a piezoelectric sheet made of a PFA / PTFE nonwoven fabric / PFA laminate may be used for the piezoelectric layer 6. As the electromagnetic shield 30 of the piezoelectric layer 6 and the electrode pair 16, shield layers 30-1 and 30-2 are provided on the upper side and the lower side. As the electrode pair 16, the above-described pattern electrode pair is used, and for example, aluminum or the like is used as an electrode material.

As shown in FIG. 3B, the shield layer 30-1 is a laminate in which insulating layers 30-12 and 30-13 are provided on the upper and lower sides of the conductor layer 30-11. Similarly, the shield layer 30-2 is also a laminate in which insulating layers 30-22 and 30-23 are provided on the upper and lower sides of the conductor layer 30-21. For the conductor layers 30-11 and 30-21, for example, aluminum may be used as the conductor material.

The back support layer 26 corresponds to the back support layer 8 (FIG. 1) described above. The back support layer 26 includes a rigid layer 26-1 on the lower side and an elastic layer 26-2 on the upper side. The rigid layer 26-1 is formed of a metal plate such as stainless steel as a rigid material. The mat sensor 20 is installed and supported on the area-side support surface 10 with a rigid layer 26-1. The elastic layer 26-2 is made of, for example, a thermosetting polymer (epoxy resin, thermosetting rubber, polyurethane, phenol resin, imide resin, silicone resin, etc.) or a thermoplastic polymer (acrylic resin, polyolefin resin, fluorine resin, etc.) as an elastic material. ). That is, the back surface support layer 26 is firmly supported by the rigidity of the rigid layer 26-1 on the area side support surface 10 side and the elasticity of the elastic layer 26-2, and the pressure input M applied to the mat sensor 20 is supported on the back surface. It is received on the layer 26 side.

The sealing layer 28 may be formed of a sealing material and detachable from the main body side of the mat sensor 20.

In the mat sensor 20, if the thicknesses of the elastic layers 22-1 and 26-2 are D1 and D2, D1> D2 is set. When the same elasticity is provided, for example, D1 = D2 × 2 may be set. Thereby, the impact applied to the elastic layer 22-1 on the tread surface side can be absorbed, and the impact transmitted to the piezoelectric laminate 24 can be buffered. The thickness setting of the elastic layers 22-1 and 26-2 is an example. For example, if an elastic material having a high shock absorbing function is used on the elastic layer 22-1 side, the thickness setting may be D1 = D2.

<Effect of Example 1>

(1) According to this mat sensor 20, it is possible to obtain the same effect as that of the one embodiment described above.

(2) This mat sensor 20 is installed on a floor surface such as a step surface in a building or structure, as shown in FIG. 4, and the presence or absence of people or objects, passing, gathering, distribution on the floor surface, etc. Can be detected. At that time, the pressure input M is applied to the piezoelectric laminate 24 through the anti-slip layer 22-2 and the elastic layer 22-1 and is transmitted to the area side through the elastic layer 26-2 and the rigid layer 26-1 on the back support layer 26 side. It is supported by the support surface 10. Thereby, the pressure input M acts on the pressure input surface portion 14a side of the piezoelectric layer 6 to cause piezoelectric conversion, and a piezoelectric output corresponding to the level of the pressure input M can be taken out from the electrode pair 16. High sensitivity pressure detection can be performed.

(3) Since the impact can be absorbed by the elastic layer 22-1, the piezoelectric laminate 24 can be protected from the impact, and the damage of the electrode pair 16 and the impact deterioration of the detection function of the piezoelectric layer 6 can be prevented.

(4) Since the non-slip layer 22-2 is installed on the tread surface, an appropriate friction can be imparted between the bottom surface of shoes and the like, thereby preventing a person from hindering walking. Moreover, a sliding state can be prevented with a thing.

(5) マ ッ ト This mat sensor 20 does not have an elastic support structure that maintains the electrode spacing by an elastic body and turns the electrodes on and off by elastic expansion and contraction, unlike the conventional pressure switch. There is no deterioration or wear between contacts, reliable and stable pressure sensing can be maintained, and maintenance is excellent.

FIG. 5A shows a step device according to the second embodiment. The step device 40 includes the above-described mat sensor 20 together with the device housing 42. The apparatus housing 42 has, for example, a flat rectangular shape, and includes a mat sensor fixing portion 44 for housing the mat sensor 20. The mat sensor 20 is installed in the mat sensor fixing portion 44. The mat sensor 20 includes a pressure sensitive range 46 in which a pressure input M can be piezoelectrically converted, as indicated by a broken line.

The step device 40 is provided with a control unit 48, and this control unit 48 is installed on the back side of the mat sensor 20 as shown in FIG. FIG. 5B shows a cross section taken along line VB-VB in FIG. The apparatus housing 42 is formed with a substrate storage unit 50 for storing the control unit 48 on the back side of the mat sensor 20. In this example, the substrate storage unit 50 is installed at the longitudinal end of the apparatus housing 42 in the figure, but may be installed at any location.

The control unit 48 includes signal lines 52-1, 52-2 and a power supply line 54. The signal lines 52-1 and 52-2 are led to an external device, and the power line 54 is led to a power source to be fed.

<Effect of Example 2>

(1) The saddle device housing 42 can be formed of a highly rigid material such as metal, and can protect the mat sensor 20. If the material is highly rigid, the occupied volume of the device housing 42 in the step device 40 including the mat sensor 20 can be reduced.

(2) The pressure sensitive range 46 can be arbitrarily set for the detection region 4 such as a rectangular shape. In the second embodiment, the area is set to be smaller than the area of the flat portion of the apparatus housing 42, but it can be set to be equal, and the step device 40 in which the pressure sensitive range 46 is expanded can be realized.

(3) The saddle control unit 48 may be set at any position on the back surface of the mat sensor 20, and the control unit 48 can be protected by the mat sensor 20 and the apparatus housing 42, and the control operation by the detection output of the mat sensor 20 can be performed. Reliability can be maintained.

(4) According to such a step device 40, the weight can be reduced and the flattening can be achieved, and the exclusive volume for the step can be reduced.

FIG. 6A shows a building including the pressure-sensitive detection system according to the third embodiment. This pressure-sensitive detection system 38 includes the above-described step device 40.

Building 56 is an example of a building or a structure. An automatic door 60 is provided at the entrance 58 of the building 56, and a step device 40 is provided in the vicinity of the automatic door 60. The automatic door 60 opens and closes to the left and right, and a person or the like can enter and exit in the open state. The step device 40 detects pressurization received from a person or an object entering or exiting the entrance / exit.

FIG. 6B shows an example of the pressure sensitive detection device 64. The pressure-sensitive detection device 64 includes the mat sensor 20 and performs pressure-sensitive detection. In this example, a control unit 48 is provided on the building 56 side, and a power supply unit 65, a drive mechanism unit 66, and a display unit 68 are provided together with the pressure sensitive detection device 64. The power supply unit 65 is supplied with power from the power supply line 70. This power supply voltage is stepped down by a transformer 74, rectified by a rectifier 76, and converted into a drive voltage. This drive voltage is applied to the control unit 48. For example, the control unit 48 is configured by a computer, receives the sensor output of the mat sensor 20, and generates information representing the presence / absence of a person, passage, congestion status, and the like.

The drive mechanism 66 is, for example, an opening / closing drive mechanism for the automatic door 60. The display unit 68 is an example of an information presentation unit, and is controlled by the control unit 48 to present information such as the presence / absence of a person, passage, and congestion status as output information.

FIG. 7 shows the pressure-sensitive detection device 64. The control unit 48 includes an amplification unit 78, a waveform shaping unit 80, and a signal processing unit 82. The amplification unit 78 is, for example, a preamplifier, and amplifies the sensor output of the mat sensor 20. The waveform shaping unit 80 or the signal processing unit 82 is an example of a signal conversion unit. The waveform shaping unit 80 shapes the output waveform of the amplification unit 78 and converts it into, for example, a pulse waveform. The signal processing unit 82 may have a function of amplifying and extracting a pulse waveform, a waveform level determination function, and a control function of the display unit 68. That is, the determination function can determine the presence or passage of a person from the level change and obtain an output representing the determination result. The signal processing unit 82 having a control function is an example of a determination unit or a processing unit, and starts or stops the operation of the display unit 68 which is an example of a device according to the presence / absence, position, passage, or collection of a person or an object. It is also a control means which performs.

The display unit 68 receives the output of the signal processing unit 82 and displays the above-described determination result as visual information. The display unit 68 may be a meter that shows a measured value, a lamp such as an LED (Light Emitting Diode) that lights up the number of people, a speaker that outputs a judgment output by sound, or an alarm. That is, the display unit 68, together with the signal processing unit 82, is an example of a signal conversion unit that converts the pressure-sensitive output into an optical signal or a sound signal.

FIG. 8 shows the pressure-sensitive operation and the signal processing operation of the control unit 48. As shown in FIG. 8A, when a pressurization input M from a person is applied to the mat sensor 20 and the pressurization input M is released, piezoelectric outputs A1 and A2 representing it appear. That is, a sharp pulsed piezoelectric output A1 that rises sharply at the input time ta of the pressurizing input M is generated, and when the pressurizing input M shifts to the static pressure state, the piezoelectric output A1 shifts to the zero level state. When the pressurization input M is released from this static pressure state, a piezoelectric output A2 having a phase opposite to that of the piezoelectric output A1 is generated at the release time tb. Due to the piezoelectric conversion characteristics of the piezoelectric layer 6, piezoelectric outputs A1 and A2 are generated when the pressure input M changes, and the time interval T of peak conversion of the piezoelectric outputs A1 and A2 is substantially the same as the time interval from the input time ta to the release time tb. Match. Therefore, the passage of a person can be determined by using such level information and time information of the piezoelectric outputs A1 and A2.

The piezoelectric outputs A1 and A2 are amplified by the amplifying unit 78, converted into a voltage having a level suitable for waveform shaping of the waveform shaping unit 80, and input to the waveform shaping unit 80.

In the waveform shaping unit 80, waveform shaping is performed as shown in FIG. 8B, and a pulse waveform synchronized with the piezoelectric outputs A1 and A2 is obtained. That is, this pulse waveform is a rectangular shape that becomes a constant voltage at the front edge that rises in synchronization with the rise of the piezoelectric output A1, the rear edge that falls in synchronization with the fall of the piezoelectric output A2, and the time interval T between the piezoelectric outputs A1 and A2. It is a wave.

The waveform output is applied to the signal processing unit 82 and compared with the threshold voltage Vth to determine the level of the waveform output. In the signal processing unit 82, an output in which the range in which the output waveform of the waveform shaping unit 80 exceeds the threshold voltage Vth is a high level and the others are low is obtained.

As a result, as shown in FIG. 8C, the display unit 68 can obtain a display output that lights up in a range exceeding the threshold voltage Vth. That is, the presence of a person is visually displayed by this lighting display.

<Effect of Example 3>

(1) This pressure-sensitive system 38 is the same as the existing sensor system, such as a power line and two signal lines, and can be replaced with the current product.

(2) Since the mat sensor 20 without the rubber spacer is used in this pressure sensitive system 38, the functions of the piezoelectric layer 6 and its laminated body can be used effectively, and a stable operation can be obtained for a long time. The mat sensor 20 using a fluorine-based piezoelectric sheet has excellent environmental resistance and can maintain stable operation even when exposed to wind and rain.

(3) The soot mat sensor 20 includes the piezoelectric layer 6 that is a sheet-like sensor and can perform full-surface sensing, and can reduce the insensitive area, thereby increasing the detection efficiency.

(4) The soot mat sensor 20 is an organic laminate and does not have a complicated mechanism such as a mechanical part, so the price of the pressure sensitive system 38 can be reduced.

(5) The eaves stepping device 40 is provided with an LED indicator so that attention can be alerted and safety can be maintained. The step device 40 can be used not only to determine the presence of a person but also the presence / absence of an object and passage.

(6) The pressure-sensitive output of the mat sensor 20 can be used for operations such as driving start and storage of the driving mechanism 66 of the stepping device 40.

(7) Since the eaves step device 40 includes the mat sensor 20 and performs pressure-sensitive detection, it has high impact resistance, excellent maintainability, and can improve waterproofness.

(8) Since the wiring on the mat sensor 20 side can be accommodated in the apparatus housing 42 in the stepping device 40 and the output line of the control unit 48 can be minimized, the number of wirings can be reduced and smarter can be achieved.

FIG. 9 shows a mat sensor 20 according to the fourth embodiment. In the mat sensor 20, an integrating circuit 84 and an operational amplifier 86 are provided as peripheral circuits of the piezoelectric laminate 24, and are installed inside the mat sensor 20.

The integrating circuit 84 includes a capacitor 88, and this capacitor 88 is connected between the electrode pair 16 of the piezoelectric laminate 24. The integration circuit 84 uses the impedance of the piezoelectric layer 6 of the piezoelectric laminate 24 to realize an integration function with a single capacitor 88. The integrating circuit 84 and the piezoelectric laminate 24 are connected between the non-inverting terminal (+) of the operational amplifier 86 and the positive side of the power supply 90, and the integrated output of the piezoelectric output is applied to the non-inverting terminal (+) of the operational amplifier 86.

FIG. 10 shows the operation of the mat sensor 20. For example, a weight is used as the virtual pressure input, and the weight is dropped on the tread surface of the mat sensor 20. As shown in FIG. 10A, one weight is dropped at the pressure input time ta, one more weight is dropped at the time tb, one weight is removed at the time tc, and the remaining weight is released at the pressure release time td. The pressure is removed by removing one weight. Therefore, the time T from the pressure input time point ta to the pressure release time point td is the static pressure period.

As shown in FIG. 10B, the pressure input M is applied to the mat sensor 20 at the time point ta, and the piezoelectric output A1 is generated. When the pressure input M is added by dropping the second weight after the pressure input M, the piezoelectric output A2 is generated at this time tb. When one weight is removed, a reverse-phase piezoelectric output A3 is generated at the time tc, and a reverse-phase piezoelectric output A4 is generated at the time td when the weight is removed.

These piezoelectric outputs A1, A2, A3, A4 are amplified by the operational amplifier 86 and taken out, and added to the signal processing unit 82 described above.

Thereby, as shown in C of FIG. 10, a waveform shaping output is obtained. In this waveform shaping output, an output waveform B1 that rises in synchronization with the piezoelectric output A1, an output waveform B2 that rises in synchronization with the piezoelectric output A2, and an output waveform B3 that falls in synchronization with the piezoelectric output A3 are generated, and are synchronized with the piezoelectric output A4. Then, the output waveform B3 falls to 0 level.

The output waveform B1 represents a level representing one weight, the output waveform B2 represents a level representing two weights, and the output waveform B3 represents a level representing one weight. That is, the pressurization input M is started at the time point ta, and the static pressure state is maintained for a certain time from the time point ta to the pressure removal at the time point td.

In this static pressure period, if the display unit 68 described above is used, the static pressure period can be displayed by lighting as shown in FIG.

<Effect of Example 4>

(1) In this mat sensor 20, an integrating circuit 84 and an operational amplifier 86 can be built in the sensor, noise can be reduced, and the detection sensitivity of the pressure input can be increased. For example, a time integral value of 1 [ms] of the input voltage waveform can be output as a voltage.

(2) Since the mat sensor 20 includes the integration circuit 84 and the operational amplifier 86 in the sensor, the circuit configuration on the pressure-sensitive determination side can be simplified.

(3) It is possible to detect the voltage change due to pressure addition / decompression and the static pressure during the pressurization time, and obtain the voltage output for the static pressure and stepwise pressurization and depressurization. That is, a voltage output at a level corresponding to the pressure input can be taken out.

(4) ON / OFF judgment can be made by comparing the voltage output with the threshold value, and the judgment output can be released when the pressure input by the load is released.

(5) 圧 According to such pressure-sensitive determination, it is possible to easily obtain the output indicating the presence / absence of a person or an object, the collection amount or distribution thereof.

<Example of pattern electrode that can be determined>

(1) Minimizing insensitive areas

As shown in FIG. 11A, one or each of the electrode 16a and the electrode 16b has continuous circuit-like electrode portions 92-1 and 92-2 with respect to the pressure input surface portion 14a of the piezoelectric layer 6. Provided. Each of the electrode portions 92-1 and 92-2 has a continuous circuit shape that bends in a zigzag shape, and is disposed so as to cover the entire surface of the pressure input surface portion 14a of the piezoelectric layer 6. In this example, the bent portions of the electrode portions 92-1 and 92-2 are arranged so as to mesh with each other, and the detection region 4 is covered with the two electrode portions 92-1 and 92-2. In contrast to the electrodes 16a and 16b, the back electrode 16b may be a flat electrode surface.

If the electrodes 16a and 16b are provided with circuit-like electrode portions 92-1 and 92-2, the entire detection region 4 can be covered, the insensitive region can be minimized, and the detection efficiency can be increased. .

As shown in FIG. 11B, the electrodes 16a and 16b may be arranged by shifting the positions of the circuit-shaped electrode portions 92-1 and 92-2 in the vertical direction, or as shown in FIG. 11C. Further, the positions of the circuit-like electrode portions 92-1 and 92-2 may be shifted by 90 degrees.

(2) Dispersion of saddle electrodes 16a and 16b

As shown in FIG. 12A, one or each of the electrode 16a and the electrode 16b may be divided into small rectangular electrode portions 94-1 and 94-2, and the detection region 4 may be dispersed. According to this configuration, the pressure sensitivity can be stabilized by dispersing the electrodes 16a and 16b. If a pressure input M occurs across the electrode portions 94-1 and 94-2 as in the shoe mark 96 indicated by a broken line, a piezoelectric output can be obtained from both the electrode portions 94-1 and 94-2. Can do.

As shown in FIG. 12B, each of the electrodes 16a and 16b may be divided into three electrode portions 98-1, 98-2, and 98-3, and the detection region 4 may be dispersed. In this case, an isosceles triangular electrode portion 98-1 is arranged in the center of the rectangular detection region 4, and right isosceles triangular electrode portions 98-2 and 98-3 are provided on the respective oblique sides of the electrode portion 98-1. Has been placed. According to such a configuration, the pressure sensitivity can be similarly stabilized by dispersing the electrode 16a or the electrode 16b. In this case, if a pressure input M is generated across the electrode portions 98-1 and 98-2 as shown by the shoe mark 96 indicated by a broken line, a piezoelectric output is applied to both the electrode portions 98-1 and 98-2. Is obtained.

(3) 破 断 Compensation of fractured part by bypass circuit

As shown in FIG. 13A, the first and second electrode lead portions 100-1 and 100-2 may be provided on either or each of the electrode 16a and the electrode 16b. As shown in FIG. 13B, even if the fracture 102 occurs in the electrode lead-out portion 100-1, the electrode lead-out portion 100-2 can be used for taking out the piezoelectric output, and a stable detection operation can be maintained.

As shown in FIG. 14A, the electrodes 16a and 16b are divided into a plurality of electrode portions 104-11, 104-12,... 104-33 and arranged in a matrix, and each electrode portion 104-11, 104-12... 104-33 may be connected by a bridging portion 106 to be electrically integrated, and a plurality of electrode lead portions 108-1, 108-2, 108-3 may be provided. That is, the plurality of electrode portions 104-11, 104-12,... 104-33 and the bridging portion 106 form a mutual bypass circuit. With such a configuration, as shown in FIG. 14B, even if the electrode lead portions 104-11, 104-12,... 104-33 and the plurality of bridging portions 106 are broken 102, the electrode portions The piezoelectric output due to the pressure input M generated in 104-31 can be taken out from the electrode lead-out portions 108-2 and 108-3.

(4) Strengthening the flexibility of the saddle electrode parts 16a and 16b

As shown in FIG. 15A, a plurality of notches 110 are formed from each side of the electrodes 16a and 16b toward the center, and the electrode portions 112-1, 112-2, 112-3 and 112-4 may be formed. According to such a configuration, the electrode lead-out function of the bendable electrodes 16a and 16b can be complemented, and the bendability of the electrodes 16a and 16b is complemented by the respective electrode portions 112-1, 112-2, 112-3, and 112-4. Can be strengthened.

(5) Saddle electrode parts 16a, 16b on the same plane

15B, the electrodes 16a and 16b of the electrode pair 16 may be arranged in the width direction of the detection region 4. The electrodes 16a and 16b arranged on the same surface may be disposed on either the pressure input surface portion 14a or the support surface portion 14b of the piezoelectric layer 6.

<Example of pattern electrode capable of position determination>

(6) Specification of position on X axis

As shown in FIG. 16A, the electrodes 16a, 16b include a plurality of electrode portions 114-1, 114-2, 114-3,..., And these electrode portions 114-1, 114-2, 114-3,. .. May be arranged in the X-axis direction. In this way, the piezoelectric output representing the position on the X-axis can be taken out by the electrode portions 114-1, 114-2, 114-3,. In this case, a piezoelectric output representing the position of the shoe print 96 on the X-axis is obtained at the electrode portion 114-1 having the shoe print 96.

(7) 位置 Specify position on Y-axis

As shown in FIG. 16B, the electrodes 16a, 16b include a plurality of electrode portions 116-1, 116-2, 116-3, 116-4,..., And these electrode portions 116-1, 116-2, 116-3, 116-4,... May be arranged in the Y-axis direction. In this way, the piezoelectric output representing the position on the Y axis can be taken out by the electrode portions 116-1, 116-2, 116-3, 116-4,. In this case, a piezoelectric output representing the position of the shoe print 96-1 on the Y-axis is obtained at the electrode portion 116-1 where the shoe print 96-1 is provided. As indicated by the broken line, when the shoe print 96-1 moves to the shoe print 96-2, the piezoelectric output representing the moved position on the Y-axis is taken out from the electrode portions 116-1 and 116-2.

(8) Specify position on X and Y axes

As shown in FIG. 17A, the electrode 16a includes a plurality of electrode portions 118-1, 118-2, 118-3, 118-4, and the electrode 16b includes a plurality of electrode portions 118-5, 118-6. , 118-7, 118-8. The electrode 16b is disposed below the electrode 16a with the piezoelectric layer 6 interposed therebetween. The electrodes 16a and 16b are arranged in a matrix in the X-axis direction and the Y-axis direction on the pressure input surface and the back surface, respectively, and the electrode portions 118-1, 118-2, 118-3, 118-4, 118-5. , 118-6, 118-7, 118-8 constitute an electrical bridge portion of the same interval to bridge each electrode portion, and each electrode portion on the peripheral side has an X-axis direction and a Y-axis direction. An electrode lead portion is formed.

With this configuration, when the pressure input M is applied from the pressure input surface, the electrode portions 118-1, 118-2, 118-3, 118-4, and 118-5, 118-6 are provided. , 118-7, 118-8, or a combination of a plurality of piezoelectric outputs. It is possible to know the coordinate position on the X-axis and Y-axis of the pressure input M where the piezoelectric output is generated.

(9) 位置 Specify the position on the X, Y, and Z axes

As shown in FIG. 17B, the pressure-sensitive sensor 2-1 for detecting the pressure input M on the XY axis is provided on the upper and lower surfaces of the block-like elastic support 120, and the pressure input on the Z-axis is provided on the side surface. A pressure sensor 2-2 for detecting M is provided. An electrode 16a and an electrode 16b are provided on the pressure sensor 2-1 side with the piezoelectric layer 6 interposed therebetween. The electrode 16a includes a plurality of electrode portions 118-1, 118-2, 118-3, 118-4, and an electrode 16b. Is provided with a plurality of electrode portions 118-5 and 118-6. The plurality of electrode portions 118-1, 118-2, 118-3, 118-4, 118-5, and 118-6 are arranged at intervals on the XY axis described above. A plurality of electrode portions 122 are arranged at intervals on the pressure-sensitive sensor 2-2 side. Although not shown, the electrode 122 on the pressure sensor 2-2 side may also be an electrode pair disposed with the piezoelectric layer 6 interposed therebetween, or the piezoelectric layer 6 may be sandwiched laterally on the pressure input surface of the piezoelectric layer 6. May be arranged.

In this configuration, the piezoelectric output by the pressure input M applied on the XY axis can be taken out from the pressure sensor 2-1 and the piezoelectric output by the pressure input M applied on the Z axis from the pressure sensor 2-2. Can be taken out.

<Pattern electrode example capable of distribution determination>

As shown in FIG. 18A, when a plurality of pressure inputs M1, M2,... MN are added to the electrodes 16a and 16b, piezoelectric outputs are generated in the X-axis direction and the Y-axis direction. The coordinate positions on the X and Y axes of the pressure inputs M1, M2,... MN can be known, and the distribution of the pressure inputs M1, M2,.

<Pattern electrode example capable of direction determination>

As shown in FIG. 18B, when a pressure input M is applied to the pressure sensor 2-1 on the XY axis from the tilt direction, the input of the pressure input M from the pressure sensor 2-1 is applied. A piezoelectric output representing the angle is obtained.

FIG. 19 shows an example of a pressure-sensitive detection device according to the sixth embodiment. The pressure sensing device 124 includes a pressure sensor 2, a waveform shaping unit 126, a signal processing unit 128, a control unit 130, and a power supply unit 132.

The pressure sensor 2 may include a single or a plurality of piezoelectric layers 6 and electrode pairs 16. The waveform shaping unit 126 has the same function as the waveform shaping unit 80 described above.

The signal processing unit 128 and the control unit 130 are, for example, configured by a computer, and are an example of a processing unit that performs processing including entry, passage, or gathering of a person or an object into a specific area, and these various types of signal processing are possible. . The signal processing unit 128 can perform various signal processing, and the control unit 130 can perform various control operations such as start / stop control of various devices based on the signal processing.

The power supply unit 132 may be a battery or may generate a drive voltage using a commercial power supply.

<Signal processing and control operations>

a) Accumulation process of pressurization input M In addition to the integration process of pressurization input M, the determination process of the magnitude of pressurization input M, the addition process of pressurization input M, and pressurization input M are predetermined in this integration process. Processing such as determination of whether or not the value has been exceeded is included. According to this integration process, it is possible to determine the weight of a person or an object, the boarding restrictions on the aircraft based on the determination result, the determination of the cargo weight deviation, the boarding situation for adults and children, and the like.

b) Frequency of pressurization input M The number of pressurization inputs M may be counted, and it may be determined whether or not the count value exceeds a certain value. Count the number of people and things entering and leaving, and restrict entry if it exceeds a certain number.

c) Distribution processing of the pressure input M The size and time point, location, or size and number of the pressure input M, and the location and number of times may be recorded. The distribution state of the pressure input M from the object can be visualized. It can be used to determine the traceability of luggage.

d) Correlation processing of a plurality of pressure inputs M The pressure input M is recorded, and the regularity is determined based on the record. By placing a pressure sensor on the bed and judging the sleeping posture from pressure input M, and placing a pressure sensor on the sole, it is possible to determine how to walk and run from the sole pressure. It is.

e) Estimation process If the average value of the pressure input M is obtained, for example, the uniformity of the roll surface pressure can be estimated.

f) Testing process A plurality of pressure inputs M can be compared to determine a difference between the pressure inputs M or a group in which the plurality of pressure inputs M are assembled. For example, in the 100% inspection, the pressure input M (weight) is determined, and the size is used for the pass / fail determination.

g) Dispersion processing The dispersion can be obtained from the average value of a plurality of pressure inputs M. For example, the degree of the scattered state of the cleaning liquid is examined. It can be used for designing the shape of cleaning equipment.

h) Signal processing according to the pressure level of the pressure input M is possible.
h-1) The device is driven and stopped from the voltage and the signal indicating the operation state. It can be used for camera shutter operation, for example, in conjunction with X-ray imaging with an automatic ticket gate.

H-2) Automatic opening / closing operation: For example, it can be used for automatic opening when it is caught in a door. Also, as a sorting operation: for example, when used to estimate whether or not liquid is brought in, it may be determined from voltage attenuation after the package is shaken.

H-3) From the signals representing voltage and sound, judge the directivity from the falling of objects, entering the restricted area, and stepping on the braille block, and output voice guidance.

H-4) Color display may be performed by counting the number of times pressure is received from signals representing voltage and light.

<Effects of Example 6>

(1) The pressure sensor 2 can be used in various fields involving pressurization and can be used to detect pressure levels and pressure distribution.

(2) Since the user can be informed of the pressurized state, the convenience of various devices can be enhanced by providing a pressure-sensitive sensor.

[Other Embodiments]

(1) In the above-described embodiment or example, it is exemplified that pressure input from a person or an object is detected. However, the pressure sensor 2 may be used to detect a person's movement or heartbeat.

(2) The above-described pressure-sensitive sensor 2 may be used for detecting a pressurizing point in sports or games.

(3) The eaves step device 40 may be used to detect the entry and exit of ships, aircraft, rooms, and people.

As described above, the most preferred embodiments and examples of the present invention have been described. The present invention is not limited to the above description. Various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the claims or in the embodiments or examples for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present invention.

Industrial applicability

According to the present invention, it can be applied to a step device or the like, and can be used to determine the presence / absence of a person or an object, passage, gathering, etc.

2 Pressure-sensitive sensor 4 Detection area 6 Piezoelectric layer 8 Back support layer 10 Area side support surface 12 Pressure transmission layer 14a Pressurization input surface portion 14b Support surface portion 16 Electrode pair 16a, 16b Electrodes 16a-1, 16a-2, 16b-1, 16b-2 Electrode portion 18 Insulation interval 20 Mat sensor 22 Pressure receiving layer 22-1 Elastic layer 22-2 Non-slip layer 24 Piezoelectric laminate 26 Back support layer 26-1 Rigid layer 26-2 Elastic layer 28 Sealing layer 30-1 , 30-2 Shield layer 30-11, 30-21 Conductor layer 30-12, 30-13, 30-22, 30-23 Insulating layer 38 Pressure sensitive detection system 40 Step device 42 Device housing 44 Mat sensor fixing portion 46 Pressure sensing range 48 Control unit 50 Substrate storage unit 52-1, 52-2 Signal line 54 Power supply line 56 Building 58 Entrance / exit 60 Automatic door 64 Pressure detection Device 65 Power supply unit 66 Drive mechanism unit 68 Display unit 74 Transformer 76 Rectifier 78 Amplification unit 80 Waveform shaping unit 82 Signal processing unit 84 Integration circuit 86 Operational amplifier 88 Capacitor 90 Power supply 92-1, 92-2, 94-1, 94- 2, 98-1, 98-2, 98-3, 104-11, 104-12... 104-33, 112-1, 112-2, 112-3, 112-4, 114-1, 114 -2, 114-3, 116-1, 116-2, 116-3, 116-4, 118-1, 118-2, 118-3, 118-4, 118-5, 118-6, 118-7 , 118-8, 122 Electrode part 96, 96-1, 96-2 Shoe mark 100-1, 100-2, 108-1, 108-2, 108-3 Electrode lead part 102 Fracture 106 Bridge part 110 Notch part 120 Sexual feeling support 124 pressure detector 126, the waveform shaping section 128 signal processing section 130 the control unit 132 Power unit

Claims (12)

1. A single or multiple piezoelectric layers with a pressure input surface are installed in the pressure input detection area.
   At least one electrode of a single or a plurality of electrode pairs arranged with the piezoelectric layer in between is a patterned electrode having a continuous electrode portion or a plurality of electrode portions narrower than the pressure input surface portion,
   A pressure-sensitive detection method for receiving pressure input to the pattern electrode and extracting a pressure-sensitive output from the pattern electrode.
2. Single or multiple piezoelectric layers having a pressure input surface in the pressure input detection area;
   A single or a plurality of electrode pairs disposed across the piezoelectric layer; and
   A pattern electrode that is provided on at least one electrode of the electrode pair, includes a plurality of electrode portions narrower than the pressure input surface portion, and receives pressure input;
   And a pressure-sensitive sensor that takes out a pressure-sensitive output obtained by the pressure input from the plurality of electrode portions included in the pattern electrode.
3. 3. The pattern electrode includes a plurality of electrode portions for extracting any one or two or more of pressure-sensitive outputs indicating the level, position, direction, or range of the pressure input, and outputs indicating a distribution of the plurality of pressure inputs. The pressure-sensitive sensor described in 1.
4. The pressure sensor according to claim 2 or 3, wherein the pattern electrode includes a plurality of electrode portions disposed on any one or more of a plane, a back surface, and a side surface of the piezoelectric layer.
5. The pattern electrode includes a single or a plurality of electrode portions that are continuously bent on the pressure input surface of the piezoelectric layer, a plurality of electrode portions obtained by dividing the single electrode portion into two or more, and a pressure applied to the piezoelectric layer. The input surface includes any of a plurality of electrode portions arranged in the X-axis direction, the Y-axis direction, or the Z-axis direction, or a plurality of electrode portions branched in any plurality of directions of the pressure input surface. Item 5. The pressure-sensitive sensor according to any one of Items 2 to 4.
6. Furthermore, at least a shield layer that shields the electrode pair;
   The pressure-sensitive sensor according to any one of claims 2 to 5, further comprising:
7. A viscoelastic protective layer covering the piezoelectric layer;
   A non-slip layer installed on the outer surface of the viscoelastic protective layer;
   The pressure-sensitive sensor according to any one of claims 2 to 6, further comprising:
8. Further, a rigid layer that is interposed between the piezoelectric layer and the supporting means and supports the laminate including the piezoelectric layer;
   The pressure-sensitive sensor according to any one of claims 2 to 7, further comprising:
9. A pressure-sensitive sensor according to any one of claims 2 to 8;
   A determination means for determining the presence or absence of a person or an object, a position, a passage, or a set using a pressure-sensitive output of the pressure-sensitive sensor;
   A pressure-sensitive detection device.
10. A pressure-sensitive sensor according to any one of claims 2 to 8;
    A signal converter for converting the sensor output of the pressure sensor into a sound signal or an optical signal;
    A pressure-sensitive detection device.
11. A pressure-sensitive sensor according to any one of claims 2 to 8;
    In accordance with the sensor output level of the pressure sensor, a control unit that outputs a control signal for starting and stopping the operation of the control target device;
    A pressure-sensitive detection device.
12. A pressure-sensitive sensor according to claim 2 or claim 8, or a pressure-sensitive detection device according to claims 9 to 11;
    An area where the pressure sensor or the pressure detection device is installed and a person or an object passes or gathers;
    Processing means for performing processing including passing or gathering of persons or objects in the area from the sensor output of the pressure sensor included in the pressure sensor or the pressure detection device;
    Presenting means connected to the processing means by wire or wireless and presenting a processing result of the processing means;
    A pressure-sensitive detection system.
    

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