JP6639802B2 - Fabric-like piezoelectric sensor and shoe insole using the same - Google Patents

Description

  The present invention relates to a transducer mounted on a shoe insole, which functions as a piezoelectric sensor that outputs an electric signal due to a change in shape due to a change in load distribution on the sole during exercise. Further, the present invention relates to a shoe insole functioning as a device using a signal from the transducer.

  In recent years, so-called wearable sensors have attracted attention, and products having shapes such as eyeglasses, watches, and shoes have begun to appear. However, these devices have a feeling of being worn, and a cloth-like device that is ultimate wearable is desired. As such a sensor, a sensor in which a piezoelectric element is attached to a cloth and a signal is extracted therefrom is disclosed (Patent Documents 1 and 2). However, since these require a separate structure on the surface of the woven or knitted fabric, it is difficult to adapt to a free-form surface and has a poor tactile sensation. . In addition, there is a structure in which a cloth-like structure is formed from a piezoelectric material and a conductive material in the form of a film (Patent Document 3). However, this is also difficult to adapt to a free-form surface, has a poor tactile sensation, and is easy to handle. Lack of practicality such as causing troubles in workability and workability. In particular, shoes are one of the items for which a feeling of wearing is important, and when used for insole of shoes, poor touch feeling becomes a serious problem. If this problem is solved, there is a possibility that the present invention can be applied not only to sports but also to a wide range of uses such as detection of fall / posture of the elderly.

  A sensor that detects the resistance between conductive fibers has also been proposed as a cloth-like sensor composed of only fibers (Patent Document 4), but it detects pressure on the cloth and does not directly detect a change in shape. Was. Patent Document 5 discloses a piezoelectric element including two conductive fibers and one piezoelectric fiber, each of which has a contact point with each other, and includes a piezoelectric unit which is arranged on substantially the same plane. Have been.

JP 2007-518886 A JP-A-6-323929 JP-A-2002-203996 JP 2006-284276 A International Publication No. WO 2014/058077

  It is an object of the present invention to provide a fabric-like transducer with high flexibility by fabricating a conventional woven or knitted structure using a fiber material, and to provide a shoe insole equipped with the transducer. It is in. It is still another object to provide a shoe insole provided with a device using a signal from the transducer. It is still another object of the present invention to provide a shoe insole provided with a combination of the transducer and a sensor having a different type of data that can be obtained, such as an acceleration sensor.

  The present inventors have discovered that a combination of conductive fibers and piezoelectric fibers may function as a piezoelectric element, and made a fabric-like piezoelectric sensor using this principle, and mounted it on a shoe insole. Thus, the present invention has been completed.

That is, the present invention includes the following inventions.
1. With the insole body,
A cloth-shaped or braid-shaped piezoelectric sensor mounted on the insole body,
Insole with shoes.
2. The shoe insole according to the above item 1, further comprising another sensor mounted on the insole body and capable of acquiring data different from the piezoelectric sensor.
3. 3. The shoe insole according to claim 2, wherein the other sensor is an acceleration sensor.
4. The shoe insole according to any one of claims 1 to 3, wherein the piezoelectric sensor includes a piezoelectric unit in which the conductive fiber and the piezoelectric fiber are substantially coplanar to provide an electrical connection. .
5. The piezoelectric unit according to claim 4, wherein the piezoelectric unit includes two conductive fibers and one piezoelectric fiber, and the conductive fiber, the piezoelectric fiber, and the conductive fiber are arranged in this order. Insole of shoes.
6. The shoe insole according to claim 4, wherein the conductive fiber and the piezoelectric fiber have a contact point in physical contact with each other.
7. The shoe according to claim 4, wherein insulating fibers are arranged such that the conductive fibers in the piezoelectric unit are not electrically connected to conductive fibers and / or piezoelectric fibers in other piezoelectric units. Insole.
8. 5. The insole according to the above item 4, wherein the piezoelectric fibers mainly contain polylactic acid.
9. The shoe insole according to the above item 4, wherein the piezoelectric fibers mainly contain poly-L-lactic acid or poly-D-lactic acid having an optical purity of 99% or more.
10. 5. The shoe insole according to claim 4, wherein the piezoelectric fibers are uniaxially oriented and include crystals.
11. The shoe insole according to the above item 4, wherein the conductive fiber is a metal-plated fiber.
12. 5. The shoe insole according to claim 4, wherein the piezoelectric sensor is a woven or knitted fabric containing a plurality of the piezoelectric units.
13. The shoe insole according to the above item 12, wherein the piezoelectric sensor is a woven fabric containing a plurality of the piezoelectric units, and a woven structure thereof is any of a plain weave, a twill weave, a satin weave, and a composite structure thereof.
14． 14. The insole according to the above 13, wherein the piezoelectric sensor uses a plurality of the woven or knitted materials in combination.
15. The piezoelectric sensor;
Amplifying means for amplifying an electric signal output from the piezoelectric sensor according to the applied pressure;
Output means for outputting the electric signal amplified by the amplification means,
The insole according to any one of the preceding claims, comprising a device comprising:
16. 16. The shoe insole according to the above item 15, further comprising a transmitting means for transmitting the electric signal output from the output means to an external device.
17． The piezoelectric sensor;
Output means for outputting an electric signal from the piezoelectric sensor according to the applied pressure;
Transmission means for transmitting the electric signal output from the output means to an external device,
The insole according to any one of the preceding claims, comprising a device comprising:

  According to the present invention, it is possible to obtain a fabric-like transducer with high flexibility by using a fiber material and fabricating a conventional woven or knitted structure, which is mounted on a shoe insole as a cloth-like piezoelectric sensor. By doing so, it is possible to obtain a shoe insole (sensor) capable of acquiring the movement of the foot and the load movement of the sole. Note that since the transducer of the present invention can take out an electric signal as an output, the transducer can be used as a power source or a power generating element for operating another device.

It is a schematic diagram of the satin fabric of Example 1. FIG. 2 is a schematic diagram of an insole sensor according to the first embodiment. It is a functional block diagram showing an insole of shoes using the transducer of the present invention. It is a functional block diagram showing other shoe insoles using the transducer of the present invention. It is a functional block diagram showing the insole of the shoe which used the transducer of the present invention for electric power generation.

The object of the invention is achieved by a transducer for outputting an electrical signal comprising a piezoelectric element comprising a piezoelectric unit in which conductive fibers and piezoelectric fibers are arranged substantially coplanar to provide an electrical connection. . By cutting this cloth-like transducer according to the shape of the insole of the shoe and mounting it on the insole of the shoe, the insole with a piezoelectric sensor can be obtained. Further, since the kind of data that can be obtained, such as an acceleration sensor is mounted on a shoe insoles with different sensors, not only a load moving the foot movement and plantar, for example, complex, such as travel distance and travel speed Insoles that can be obtained together with important information. Hereinafter, each configuration will be described.

(Conductive fiber)
As the conductive fiber, any known conductive fiber may be used, and any known fiber may be used, for example, a metal fiber, a fiber made of a conductive polymer, a carbon fiber, a fibrous or granular conductive filler dispersed therein. Fibers made of a polymer that has been made, or fibers having a conductive layer provided on the surface of a fibrous material. Examples of a method for providing a conductive layer on the surface of the fibrous material include a metal coat, a conductive polymer coat, and winding of a conductive fiber. Among them, a metal coat is preferable from the viewpoint of conductivity, durability, flexibility and the like. Specific methods for coating the metal include vapor deposition, sputtering, electrolytic plating, and electroless plating, but plating is preferred from the viewpoint of productivity and the like. Such a metal-plated fiber can be referred to as a metal-plated fiber.

  As the base fiber to be coated with metal, known fibers can be used with or without conductivity, for example, polyester fiber, nylon fiber, acrylic fiber, polyethylene fiber, polypropylene fiber, vinyl chloride fiber, aramid fiber, In addition to synthetic fibers such as polysulfone fibers, polyether fibers, and polyurethane fibers, natural fibers such as cotton, hemp, and silk, semi-synthetic fibers such as acetate, and regenerated fibers such as rayon and cupra can be used. The base fiber is not limited to these, and any known fiber can be used arbitrarily, and these fibers may be used in combination.

Any metal may be used as long as the metal coated on the base fiber exhibits conductivity and exhibits the effects of the present invention. For example, it is possible to use gold, silver, platinum, copper, nickel, tin, zinc, palladium, indium tin oxide, copper sulfide, and mixtures thereof and the like and alloys.

  As the conductive fiber, a multifilament obtained by bundling a plurality of filaments or a monofilament composed of one filament may be used. The use as a multifilament is preferred from the viewpoint of the long stability of the electrical characteristics. The diameter of the monofilament is 1 μm to 5000 μm, preferably 2 μm to 100 μm. More preferably, it is 3 μm to 50 μm. The number of filaments is preferably 1 to 100,000, more preferably 5 to 500, and still more preferably 10 to 100.

The diameter of the conductive fiber is preferably 1 μm to 10 mm, more preferably 10 μm to 5 mm, and still more preferably 0.1 mm to 2 mm . Handling decreases the strength and diameter is small, it is difficult, also, flexibility is sacrificed if a larger diameter. The cross-sectional shape of the conductive fiber is preferably circular or elliptical from the viewpoint of the design and manufacture of the piezoelectric element, but is not limited thereto.

Further, in order to efficiently extract the electric output from the piezoelectric polymer, the electric resistance is preferably low, and the volume resistivity is preferably 10 ⁻¹ Ω · cm or less, more preferably 10 ⁻² Ω · cm. cm ³ , and more preferably 10 ⁻³ Ω · cm or less. However, the resistivity of the conductive fiber is not limited to this as long as the strength can be obtained for signal detection.

(Piezoelectric fiber)
Piezoelectric fibers are fibers having piezoelectricity. The piezoelectric fibers are preferably made of a piezoelectric polymer. As the piezoelectric polymer, any polymer having a piezoelectric property such as polyvinylidene fluoride and polylactic acid can be used, but it is preferable that the polymer mainly contains polylactic acid. Polylactic acid is easily oriented by stretching after melt spinning and exhibits piezoelectricity, and is excellent in productivity in that an electric field orientation treatment required by polyvinylidene fluoride or the like is unnecessary. Furthermore, the piezoelectric fiber made of polylactic acid has a small polarization due to its tensile or compressive stress in the axial direction, and it is difficult to function as a piezoelectric element, but a relatively large electric output is obtained depending on the shear stress, It is preferable for the piezoelectric element of the present invention having a structure that easily applies a shear stress to the piezoelectric polymer.

  The piezoelectric polymer preferably contains mainly polylactic acid. The term "mainly" means preferably 90 mol% or more, more preferably 95 mol% or more, and still more preferably 98 mol% or more.

  As polylactic acid, depending on its crystal structure, L-lactic acid, poly-L-lactic acid obtained by polymerizing L-lactide, D-lactic acid, poly-D-lactic acid obtained by polymerizing D-lactide, and the like. There are stereocomplex polylactic acid and the like having a hybrid structure, but any of them can be used as long as they exhibit piezoelectricity. Poly-L-lactic acid and poly-D-lactic acid are preferred from the viewpoint of high piezoelectric modulus. Since poly-L-lactic acid and poly-D-lactic acid each have the opposite polarization with respect to the same stress, they can be used in combination depending on the purpose. The optical purity of polylactic acid is preferably 99% or more, more preferably 99.3% or more, and further preferably 99.5% or more. If the optical purity is less than 99%, the piezoelectric modulus may be significantly reduced, and it may be difficult to obtain a sufficient electric output due to a change in the shape of the piezoelectric fiber. The piezoelectric polymer mainly contains poly-L-lactic acid or poly-D-lactic acid, and the optical purity thereof is preferably 99% or more.

  The piezoelectric fibers are preferably uniaxially oriented in the fiber axis direction of the fibers and contain crystals, more preferably uniaxially oriented polylactic acid having crystals. This is because polylactic acid exhibits large piezoelectricity in its crystalline state and uniaxial orientation.

  Since polylactic acid is a polyester which hydrolyzes relatively quickly, when moisture and heat resistance becomes a problem, a known hydrolysis inhibitor such as an isocyanate compound, an oxazoline compound, an epoxy compound, and a carbodiimide compound may be added. . Further, if necessary, an antioxidant such as a phosphoric acid compound, a plasticizer, a photodegradation inhibitor and the like may be added to improve the physical properties.

  Polylactic acid may be used as an alloy with other polymers. However, if polylactic acid is used as the main piezoelectric polymer, the polylactic acid contains at least 50% by weight or more based on the total weight of the alloy. It is preferably at least 70% by weight, more preferably at least 90% by weight.

  Examples of the polymer other than polylactic acid when the alloy is used include, but are not limited to, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate copolymer, and polymethacrylate. Any polymer may be used as long as the desired piezoelectric properties are exhibited.

  As the piezoelectric fiber, a multifilament obtained by bundling a plurality of filaments may be used, or a monofilament composed of one filament may be used. The use as a multifilament is preferred from the viewpoint of the long stability of the electrical characteristics. When used as a monofilament, the yarn diameter is 1 μm to 5000 μm, preferably 50 μm to 1000 μm. When used as a multifilament, the single yarn diameter is 0.1 μm to 5000 μm, and preferably 2 μm to 100 μm. More preferably, it is 3 μm to 50 μm. The number of filaments of the multifilament is preferably from 1 to 100,000, more preferably from 5 to 500, and still more preferably from 10 to 100.

  In order to make the above piezoelectric polymer into piezoelectric fibers, any known method for fiberizing the polymer can be adopted as long as the effects of the present invention are exhibited, and the piezoelectric polymer can be extruded. Forming and fiberizing, melt spinning piezoelectric polymer into fibers, dry or wet spinning of piezoelectric polymer, and spinning piezoelectric polymer into fibers by electrostatic spinning Etc. can be adopted. Known spinning conditions may be applied according to the piezoelectric polymer to be employed, and a melt spinning method which is industrially easy to produce may be employed.

  As described above, when the piezoelectric polymer is polylactic acid, the fiber is preferably stretched because it is uniaxially stretched and oriented, and if it contains crystals, exhibits greater piezoelectricity.

(Substantially on the same plane)
In the piezoelectric element of the present invention, two conductive fibers and one piezoelectric fiber are arranged on substantially the same plane. Here, “substantially on the same plane” means that the fiber axes of the three fibers are arranged on a substantially plane, and “substantially” means that the thickness is generated at the intersection of the fibers. Is what you do.

  For example, a form in which one piezoelectric fiber is further aligned in parallel between two parallel conductive fibers is a form that is substantially on the same plane. Further, even if the fiber axis of the one piezoelectric fiber is inclined so as not to be parallel to the two parallel conductive fibers, they are substantially on the same plane. Further, it is assumed that one conductive fiber and one piezoelectric fiber are aligned in parallel, and another conductive fiber intersects the aligned conductive fiber and piezoelectric fiber. Are also substantially coplanar.

  By being arranged on a substantially flat surface, it is easy to form a piezoelectric element in the form of a cloth by combining the piezoelectric units, and if the piezoelectric element in the form of a cloth is used, the degree of freedom in designing the shape of the transducer is increased. Can be.

  The relationship between the piezoelectric fiber and the conductive fiber is appropriately selected according to the shape change to be detected.

(Placement order)
The arrangement of the fibers in the piezoelectric unit is not particularly limited as long as the conductive fibers and the piezoelectric fibers are arranged to provide an electrical connection. For example, when the piezoelectric unit is a piezoelectric unit composed of two conductive fibers and one piezoelectric fiber, the conductive fiber, the piezoelectric fiber, and the conductive fiber may be arranged in this order. preferable. By arranging in this manner, the two conductive fibers of the piezoelectric unit do not come into contact with each other, and the piezoelectric fibers can be applied without applying other means to the conductive fibers, for example, a technique of coating an insulating material. It can function effectively as a unit.

  At this time, it is desirable that the conductive fiber and the piezoelectric fiber have a contact point that makes physical contact with each other, but if the distance between the conductive fiber and the piezoelectric fiber is within a range of 4 mm or less, it is physically possible. An electrical connection can be provided without contact. The distance between the conductive fiber and the piezoelectric fiber is more preferably 3 mm or less, further preferably 2 mm or less, further preferably 1 mm or less, and most preferably 0.5 mm or less. If this interval exceeds 4 mm, the electric output accompanying the change in the shape of the piezoelectric fiber becomes small, and it becomes difficult to use it as a transducer.

  Examples of the form include a form in which two conductive fibers are arranged in parallel and one piezoelectric fiber is further arranged in parallel between the two conductive fibers, and a form in which two conductive fibers are arranged in parallel. Are arranged in parallel, and one piezoelectric fiber is arranged so as to intersect these two conductive fibers. Further, two conductive fibers may be arranged as a warp (or weft), and one piezoelectric fiber may be arranged as a weft (or warp). In this case, it is preferable that the two conductive fibers are not in contact with each other, and it is preferable that an insulating substance, for example, an insulating fiber be interposed between the two conductive fibers. It is also possible to adopt a form in which an insulating substance is coated only on the surface that is easily contacted, and the conductive fiber is in direct contact with the piezoelectric fiber.

(Insulating fiber)
The piezoelectric unit of the present invention includes insulating fibers, and the insulating fibers are formed of conductive fibers and piezoelectric fibers so that the conductive fibers in the piezoelectric unit do not contact other conductive fibers and the piezoelectric fibers. May be placed between. At this time, as the insulating fiber, an elastic material and a fiber having a shape can be used for the purpose of improving the flexibility of the cloth. Further, the conductive fibers in the piezoelectric unit may be arranged so as not to contact the conductive fibers and the piezoelectric fibers in other piezoelectric units. Since the arrangement order in the present invention is usually [conductive fiber / piezoelectric fiber / conductive fiber], the insulating fiber is [insulating fiber / conductive fiber / piezoelectric fiber / conductive fiber] or It is arranged as [insulating fiber / conductive fiber / piezoelectric fiber / conductive fiber / insulating fiber]. In this case, as the insulating fiber, an elastic material or a fiber having a shape can be used for the purpose of improving the flexibility of the fabric.

  By arranging the insulating fibers in the piezoelectric unit in this manner, even when a plurality of piezoelectric units are combined, the conductive fibers do not come into contact, and the performance as a transducer can be improved.

As such an insulating fiber, a volume resistivity of 10 ⁶ Ω · cm or more can be used, more preferably 10 ⁸ Ω · cm or more, and further preferably 10 ¹⁰ Ω · cm or more.

  Examples of insulating fibers include synthetic fibers such as polyester fiber, nylon fiber, acrylic fiber, polyethylene fiber, polypropylene fiber, vinyl chloride fiber, aramid fiber, polysulfone fiber, polyether fiber, and polyurethane fiber, as well as cotton, hemp, silk, and the like. Natural fibers, semi-synthetic fibers such as acetate, and regenerated fibers such as rayon and cupra can be used. The present invention is not limited to these, and known insulating fibers can be arbitrarily used. Further, these insulating fibers may be used in combination, or may be combined with non-insulating fibers to obtain fibers having insulating properties as a whole.

  As the insulating fiber, a multifilament obtained by bundling a plurality of filaments may be used, or a monofilament composed of one filament may be used. Use as a multifilament is preferable from the viewpoint of long stability of insulating properties. When used as a monofilament, the yarn diameter is 1 μm to 5000 μm, preferably 50 μm to 1000 μm. When used as a multifilament, the single yarn diameter is 0.1 μm to 5000 μm, and preferably 2 μm to 100 μm. More preferably, it is 3 μm to 50 μm. The number of filaments of the multifilament is preferably from 1 to 100,000, more preferably from 5 to 500, and still more preferably from 10 to 100.

  Further, for the purpose of imparting flexibility to the fabric, fibers of any known shape can be used.

(Combination of piezoelectric units)
In the present invention, a woven or knitted fabric containing a plurality of parallel piezoelectric units is preferable. With such a configuration, it is possible to improve the degree of freedom of shape deformation (flexibility) as a piezoelectric element.

  Such a woven / knitted shape includes a plurality of piezoelectric units, and is not limited as long as it functions as a piezoelectric element. In order to obtain a woven or knitted shape, knitting and weaving may be performed with a normal loom or knitting machine.

  Examples of the woven structure of the woven fabric include a mihara structure such as a plain weave, a twill weave, and a satin weave, a change structure, a single double structure such as a vertical double weave and a horizontal double weave, and a vertical velvet.

  The type of the knit may be a circular knit (weft knit) or a warp knit. Preferable examples of the structure of a circular knit (weft knit) include a flat knit, a rubber knit, a double-sided knit, a pearl knit, a tack knit, a floating knit, a one-sided knit, a lace knit, and a spliced knit. Examples of the warp knitting structure include a single denby knit, a single atlas knit, a double cord knit, a half tricot knit, a fleece knit, and a jacquard knit. The number of layers may be a single layer or two or more layers. Further, a raised woven fabric or a raised knitted fabric composed of a raised portion made of a cut pile and / or a loop pile and a ground tissue portion may be used.

  When the piezoelectric unit is incorporated in a woven or knitted structure, the piezoelectric fiber itself has a bent portion. However, in order to efficiently exhibit the piezoelectric performance as a piezoelectric element, the bending of the piezoelectric fiber is required. The smaller the part, the better. Therefore, a woven fabric is preferable for a woven fabric and a knitted fabric.

  Even in this case, as described above, the smaller the bending portion of the piezoelectric fiber, the more efficiently the piezoelectric performance is exhibited. Therefore, the weave structure is preferably a twill weave rather than a plain weave, and a satin weave (satin weave) rather than a twill weave. Is preferred. In particular, among the satin weaves (satin weaves), it is preferable that the number of jumps be in the range of 3 to 7, since the retention of the weave structure and the piezoelectric performance are exhibited at a high level.

The woven structure is appropriately selected according to the shape change to be detected. For example, when it is desired to detect bending, it is preferable that the plain woven structure, the piezoelectric fiber and the conductive fiber are in a parallel relationship, and when it is desired to detect torsion, the satin woven structure, the piezoelectric fiber and the conductive fiber are preferably it is preferable that a straight exchange relationship.

In addition, since polylactic acid, which is a piezoelectric fiber, is easily charged, it may easily malfunction. In such a case, the piezoelectric fiber from which a signal is to be taken out can be used by grounding (earthing). As a method of grounding (earthing), it is preferable to arrange a conductive fiber separately from the conductive fiber for extracting a signal. In this case, the volume resistivity of the conductive fiber is preferably 10 ⁻¹ Ω · cm or less, more preferably 10 ⁻² Ω · cm or less, and still more preferably 10 ⁻³ Ω · cm or less.

(Multiple piezoelectric elements)
It is also possible to use a plurality of piezoelectric elements side by side. The arrangement may be one-dimensionally arranged in one step, two-dimensionally superimposed, and further, may be used by knitting and weaving in a cloth shape, or may be braided into a braid. Thereby, a cloth-like or string-like piezoelectric element can be realized. In the form of a cloth or a string, as long as the object of the present invention is achieved, in combination with other fibers other than the piezoelectric element, mixed fiber, cross weaving, cross knitting, or the like may be performed, or incorporated into a resin or the like. May be used in

(Surface processing)
When a piezoelectric element (piezoelectric sensor) containing a piezoelectric unit is used for the insole of the shoe, the surface of the piezoelectric element is protected within the range that does not interfere with the function of the sensor in order to protect the woven structure of the piezoelectric element from friction with the feet and socks . It can be coated with a resin or the like, or coated with a resin sheet / film.

(Applied technology of piezoelectric element)
The transducer of the present invention, that is, the piezoelectric element including the piezoelectric unit is a piezoelectric sensor that can output contact, pressure, and shape change to the surface as an electric signal in any form, and can be used in various applications. Applicable.

  For example, FIG. 3 is a functional block diagram showing a shoe insole using the transducer of the present invention. A shoe insole 101 includes a transducer 11 (piezoelectric sensor) of the present invention, an amplifying unit 12 for amplifying an electric signal output from the transducer 11 in accordance with the applied pressure, and an electric signal amplified by the amplifying unit 12. An output unit 13 for outputting a signal, and a transmission unit 14 for wirelessly transmitting an electric signal output from the output unit 13 to an external device (not shown) are provided. The electric signal wirelessly transmitted from the transmission means 14 is electrically processed by an external device that receives the electric signal, so that the electric signal can be applied to various uses. In this manner, by mounting the transducer 11 on the insole 101 as a cloth-shaped piezoelectric sensor, it is possible to obtain an insole type sensor that can acquire, for example, the movement of the foot and the movement of the load on the sole.

  Also, for example, FIG. 4 is a functional block diagram showing another shoe insole using the transducer of the present invention. The other shoe insole 102 includes another sensor S15 in addition to the configuration of the shoe insole 101 in FIG. The other sensor S15 is mounted on an insole, and the type of data that can be obtained is different from that of a transducer (piezoelectric sensor). The other sensor S15 is, for example, an acceleration sensor. In this manner, by further mounting the other sensor S15 on the shoe insole 101, for example, a shoe insole type sensor capable of acquiring not only the movement of the foot or the load movement of the sole but also the acceleration of the foot can be provided. Obtainable.

  Note that the transducer 11 (piezoelectric sensor), the amplifying unit 12, the output unit 13, the transmitting unit 14, and the other sensor S15 constitute a device 101, and the device 101 may be mounted on a shoe insole. . In other words, the insole may be the device itself, or the insole may have the device mounted thereon.

  The amplifying unit 12, the output unit 13, the transmitting unit 14, and the (other sensor S15) are collectively configured as a sensor chip for extracting an electric signal, and are attached to the back of the arch part of the insole of the shoe, so that the Does not interfere with socks.

  As described above, by using the insole provided with the tongue transducer of the present invention, for example, when used for running shoes, it is possible to obtain data on the running distance and running speed, and also timely obtain data that assists in running form improvement. .

  In addition, since the transducer of the present invention can take out an electric signal as an output, the transducer can be used as a power source or a power generating element for operating another device. FIG. 5 is a functional block diagram showing a shoe insole using the transducer of the present invention as power generation. The insole 103 includes a transducer 11 (piezoelectric sensor) of the present invention, an amplifying unit 12 that amplifies an electric signal output from the transducer 11 according to the applied pressure, and an electric signal amplified by the amplifying unit 12. Output means 13 for outputting. With such a configuration, an electric signal output due to contact with the surface of the transducer 11, pressure, or shape change can be used as a power source for operating another device or stored in a power storage device.

  Further, not only the amplifying unit but also a known signal processing unit such as a unit for removing noise or a unit for processing in combination with another signal can be used. The order of connection of these means can be appropriately changed according to the purpose. Of course, the signal processing may be performed after the electric signal output from the transducer 11 is directly transmitted to the external device.

  Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto.

The fabric for the transducer was manufactured by the following method.
(Production of polylactic acid)
The polylactic acid used in the examples was produced by the following method.
To 100 parts by weight of L-lactide (manufactured by Musashino Chemical Laboratory Co., Ltd., optical purity 100%), 0.005 part by weight of tin octylate was added, and the mixture was heated to 180 ° C. in a nitrogen atmosphere in a reactor equipped with a stirring blade. For 2 hours, phosphoric acid in an amount equivalent to 1.2 times the amount of tin octylate was added, and then the remaining lactide was removed under reduced pressure at 13.3 Pa, and chips were formed to obtain poly-L-lactic acid (PLLA1). . The weight average molecular weight of the obtained PLLA1 was 150,000, the glass transition point (Tg) was 55 ° C., and the melting point was 175 ° C.

(Piezoelectric fiber)
PLLA1 melted at 240 ° C. was discharged from a 24-hole cap at a rate of 20 g / min, and was taken out at 887 m / min. The undrawn multifilament yarn is stretched 2.3 times at 80 ° C. and heat-set at 100 ° C. to obtain a 84 dTex / 24 filament multifilament uniaxially drawn yarn. The piezoelectric fiber A was used.

(Conductive fiber)
The conductive fiber B was HTS403K, a product name of carbon fiber multifilament manufactured by Toho Tenax Co., Ltd. The conductive fiber B was a multifilament including 3000 filaments having a diameter of 7.0 μm as one bundle, and had a volume resistivity of 1.6 × 10 ⁻³ Ω · cm.

(Insulating fiber)
Polyethylene terephthalate melted at 280 ° C. was discharged from a 48-hole cap at a rate of 45 g / min, and was taken out at a rate of 800 m / min. This undrawn yarn is drawn 2.5 times at 80 ° C. and heat-set at 180 ° C. to obtain a multi-filament drawn yarn of 167 dTex / 48 filaments. Insulating fiber C was used.

(Example 1)
As shown in FIG. 1, a twill woven fabric was prepared in which insulating fibers C were arranged in the warp and piezoelectric fibers A, conductive fibers B and insulating fibers C were alternately arranged in the weft.

  Further, as shown in FIG. 2, the twill fabric 112 of FIG. 1 was cut into the same size as the insole of the athletic shoe, and bonded to the insole body 111. On the twill fabric 112, a sensor chip 113 having a built-in acceleration sensor as a sensor chip for extracting an electric signal is attached to the back of the arch portion.

  As a result, with the insole of this athletic shoe, it was possible to confirm not only the signal of the amount of activity but also the electric signal resulting from the movement of the load to the sole during exercise.

2 Conductive fiber 3 Insulating fiber 11 Transducer 12 Amplifying means 13 Output means 14 Transmitting means 15 Sensor S
101, 102, 103 Device 110 Shoe insole 111 Insole body 112 Twill fabric 113 Sensor chip

Claims (16)

With the insole body,
A cloth-shaped or braid-shaped piezoelectric sensor mounted on the insole body,
A shoe insoles comprising said piezoelectric sensor is seen containing a piezoelectric units are arranged on substantially the same plane as the conductive fiber and a piezoelectric fiber to provide an electrical connection,
The piezoelectric sensor;
Amplifying means for amplifying an electric signal output from the piezoelectric sensor according to the applied pressure;
Output means for outputting the electric signal amplified by the amplification means,
An insole with a device that includes a .   The shoe insole according to claim 1, further comprising another sensor mounted on the insole body and having a type of data that can be obtained and different from the piezoelectric sensor.   3. An insole according to claim 2, wherein said other sensor is an acceleration sensor.   The piezoelectric unit includes two conductive fibers and one piezoelectric fiber, and the conductive fiber, the piezoelectric fiber, and the conductive fiber are arranged in this order. 3. The insole according to any one of the above items 3.   The shoe insole according to any one of claims 1 to 4, wherein the conductive fiber and the piezoelectric fiber have a contact point in physical contact with each other.   Insulating fibers are arranged such that the conductive fibers in the piezoelectric unit are not electrically connected to the conductive fibers and / or piezoelectric fibers in other piezoelectric units. An insole according to any one of the preceding claims.   The insole according to any one of claims 1 to 6, wherein the piezoelectric fibers mainly include polylactic acid.   The insole according to any one of claims 1 to 7, wherein the piezoelectric fibers mainly include poly-L-lactic acid or poly-D-lactic acid having an optical purity of 99% or more.   9. The insole according to any one of claims 1 to 8, wherein the piezoelectric fibers are uniaxially oriented and include crystals.   The insole according to any one of claims 1 to 9, wherein the conductive fiber is a metal-plated fiber.   The shoe insole according to any one of claims 1 to 10, wherein the piezoelectric sensor is a woven or knitted fabric containing a plurality of the piezoelectric units.   The insole according to claim 11, wherein the woven or knitted fabric comprises a woven fabric, and the woven structure is any of a plain weave, a twill weave, a satin weave, and a composite structure thereof.   The woven or knitted fabric includes a knitted fabric, and the type thereof is selected from the group consisting of flat knitting, rubber knitting, double-sided knitting, pearl knitting, tack knitting, floating knitting, one-sided knitting, lace knitting, spliced knitting, and composite structures thereof. Or a warp knit having a structure selected from the group consisting of a single denby knit, a single atlas knit, a double cord knit, a half tricot knit, a fleece knit and a jacquard knit and a composite structure thereof. An insole according to claim 11.   The insole according to any one of claims 11 to 13, wherein the piezoelectric sensor uses a plurality of the woven or knitted articles in combination. The insole according to any one of claims 1 to 14, wherein the device further includes a transmission unit configured to transmit an electric signal output from the output unit to an external device. The piezoelectric sensor;
Output means for outputting an electric signal from the piezoelectric sensor according to the applied pressure;
Transmission means for transmitting the electric signal output from the output means to an external device,
15. An insole according to any one of the preceding claims, comprising a device comprising: