초록 ▼

The piezo-composite curved actuator of the present invention includes a piezoelectric layer 10, a lightweight fiber-reinforced lower composite layer 20 with a high GTE (coefficient of thermal expansion) and a low modulus, which is placed under the piezoelectric layer, a lightweight fiber-reinforced

The piezo-composite curved actuator of the present invention includes a piezoelectric layer 10, a lightweight fiber-reinforced lower composite layer 20 with a high GTE (coefficient of thermal expansion) and a low modulus, which is placed under the piezoelectric layer, a lightweight fiber-reinforced upper composite layer 30 with a low GTE and a high modulus, which is placed on the piezoelectric layer, and an insulator layer 23 placed between the piezoelectric layer and the upper composite layer. The piezo-composite curved actuator may further include an insulator layer 24 placed on the upper composite layer. Also, the piezo-composite curved actuator may further include insulator layers 22 placed between the insulator layer 23 and the lower composite layer 20 at the both sides of the piezoelectric layer 10.

대표청구항 ▼

What is claimed is: 1. A curved shape actuator device composed of composite materials, comprising: an electro active material layer 10 to be deformed by an electric field; a lightweight fiber-reinforced polymer composite material layer 20 disposed under the electro active material layer 10 and havi

What is claimed is: 1. A curved shape actuator device composed of composite materials, comprising: an electro active material layer 10 to be deformed by an electric field; a lightweight fiber-reinforced polymer composite material layer 20 disposed under the electro active material layer 10 and having a high thermal expansion coefficient and a low elasticity coefficient; a lightweight fiber-reinforced polymer composite material layer 30 disposed upon the electro active material layer 10 and having a low thermal expansion coefficient and a high elasticity coefficient; and an insulating layer 23 interposed between the electro active material layer 10 and the lightweight fiber-reinforced polymer composite material layer 30. 2. The curved shape actuator device as claimed in claim 1, further comprising: insulating layers 24 and 22 formed on an outside face of the upper composite material layer 30 and on both ends of the electro active material layer 10 respectively. 3. The curved shape actuator device as claimed in claim 1, wherein the electro active material layer 10 is made of a piezoelectric ceramic, PVDF (Polyvinylidene fluoride), or a ferroelectric or electro-strictive material. 4. The curved shape actuator device as claimed in claim 1, wherein the lower composite material layer 20 is made of a glass-fiber-reinforced plastic material or an engineering plastic material. 5. The curved shape actuator device as claimed in claim 1, wherein the upper composite material layer 30 is made of a carbon fiber-reinforced plastic material or Kevlar fiber-reinforced plastic material. 6. The curved shape actuator device as claimed in claim 1, wherein the insulating layers 22, 23 and 24 are made of a glass fiber-reinforced plastic material or an engineering plastic material. 7. The curved shape actuator device as claimed in claim 1, wherein the electro active material layer is disposed departed upward or downward from a bending neutral surface. 8. The curved shape actuator device as claimed in claim 1, wherein the actuator device has a curvature variation defined as follows: Δ κ=cua쨌Ea쨌d31 쨌ΔV where cua is a coefficient (defined to be a/D) of unimorph actuator (1/N m), a is a length of a moment arm (m횞10-4) , D is a sum of a bending stiffness (N m2횞10-5) of respective laminas, Ea is an elasticity coefficient (GPa), d 31 is a piezoelectric material constant, and ΔV is an excitatory voltage (V) supplied to the electro active material layer. 9. The curved shape actuator device as claimed in claim 1, wherein the lightweight fiber-reinforced polymer composite material layers 20 and 30 and the insulating layers 22, 23 and 24 are made of adhesively superior high performance fiber-reinforced polymer prepreg composite materials. 10. The curved shape actuator device as claimed in claim 2, wherein the insulating layers 22, 23 and 24 are made of a glass fiber-reinforced plastic material or an engineering plastic material. 11. The curved shape actuator device as claimed in claim 2, wherein the lightweight fiber-reinforced polymer composite material layers 20 and 30 and the insulating layers 22, 23 and 24 are made of adhesively superior high performance fiber-reinforced polymer prepreg composite materials.