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Disclosed is a curved piezoelectric device maximizing an electrical potential of the piezoelectric material corresponding to an external mechanical stress. The curved piezoelectric device includes: a curved substrate; and a piezoelectric material provided on one surface or both surfaces of the curve

Disclosed is a curved piezoelectric device maximizing an electrical potential of the piezoelectric material corresponding to an external mechanical stress. The curved piezoelectric device includes: a curved substrate; and a piezoelectric material provided on one surface or both surfaces of the curved substrate, wherein when a stress is applied, a neutral plane in which a compressive stress and a tensile stress are balanced is located in the curved substrate, wherein the location of the neutral plane is determined by y1 and y2 of Equation 1 or 2 below, and wherein the location of the neutral plane is controllable by adjusting a thickness (d), a sectional area (A) and a Young's modulus (E) of each of the curved substrate and the piezoelectric material: wherein y1=E2⁢d2⁡(d1+d2)2⁢(E1⁢d1+E2⁢d2),y2=E1⁢d1⁡(d1+d2)2⁢(E1⁢d1+E2⁢d2)⁢⁢andEquation⁢⁢1y1=E2⁢A2⁡(A1+A2)2⁢(E1⁢A1+E2⁢A2),y2=E1⁢A1⁡(A1+A2)2⁢(E1⁢A1+E2⁢A2).Equation⁢⁢2

대표청구항 ▼

1. A curved piezoelectric device, comprising: a curved substrate; anda piezoelectric material provided on one surface or both surfaces of the curved substrate,wherein when a stress is applied, a neutral plane in which a compressive stress and a tensile stress are balanced is located in the curved su

1. A curved piezoelectric device, comprising: a curved substrate; anda piezoelectric material provided on one surface or both surfaces of the curved substrate,wherein when a stress is applied, a neutral plane in which a compressive stress and a tensile stress are balanced is located in the curved substrate,wherein the location of the neutral plane is determined by y1 and y2 of Equation 1 below, andwherein the location of the neutral plane is controllable by adjusting a thickness (d) and a Young's modulus (E) of each of the curved substrate and the piezoelectric material: y1=E2⁢d2⁡(d1+d2)2⁢(E1⁢d1+E2⁢d2),y2=E1⁢d1⁡(d1+d2)2⁢(E1⁢d1+E2⁢d2)Equation⁢⁢1where y1 is a distance between a center line of the curved substrate and the neutral plane, y2 is a distance between a center line of the piezoelectric material and the neutral plane, d1 is a thickness of the curved substrate, d2 is a thickness of the piezoelectric material, E1 is a Young's modulus of the curved substrate, and E2 is a Young's modulus of the piezoelectric material, with the proviso that y2>d22. 2. A curved piezoelectric device, comprising: a curved substrate; anda piezoelectric material provided on one surface or both surfaces of the curved substrate,wherein when a stress is applied, a neutral plane in which a compressive stress and a tensile stress are balanced is located in the curved substrate,wherein the location of the neutral plane is determined by y1 and y2 of Equation 2 below, andwherein the location of the neutral plane is controllable by adjusting a thickness (d), a sectional area (A) and a Young's modulus (E) of each of the curved substrate and the piezoelectric material: y1=E2⁢A2⁡(A1+A2)2⁢(E1⁢A1+E2⁢A2),y2=E1⁢A1⁡(A1+A2)2⁢(E1⁢A1+E2⁢A2)Equation⁢⁢2where y1 is a distance between a center line of the curved substrate and the neutral plane, y2 is a distance between a center line of the piezoelectric material and the neutral plane, d2 is a thickness of the piezoelectric material, E1 is a Young's modulus of the curved substrate, E2 is a Young's modulus of the piezoelectric material, A1 is a sectional area of the curved substrate, and A2 is a sectional area of the piezoelectric material, with the proviso that y2>d22. 3. The curved piezoelectric device according to claim 1, wherein the piezoelectric material provided on one surface or both surfaces of the curved substrate is disposed in multiple layers. 4. The curved piezoelectric device according to claim 2, wherein the piezoelectric material provided on one surface or both surfaces of the curved substrate is disposed in multiple layers. 5. The curved piezoelectric device according to claim 1, wherein the curved substrate is made of a material allowing restoration by elasticity. 6. The curved piezoelectric device according to claim 2, wherein the curved substrate is made of a material allowing restoration by elasticity. 7. The curved piezoelectric device according to claim 1, wherein the curved substrate is a substrate made of polymer material or a substrate made of steel material with elasticity. 8. The curved piezoelectric device according to claim 2, wherein the curved substrate is a substrate made of polymer material or a substrate made of steel material with elasticity. 9. The curved piezoelectric device according to claim 1, wherein the piezoelectric material is any one of polymer-based piezoelectric material and inorganic piezoelectric material, or a composite material thereof. 10. The curved piezoelectric device according to claim 2, wherein the piezoelectric material is any one of polymer-based piezoelectric material and inorganic piezoelectric material, or a composite material thereof.