ACTUATOR MANUFACTURING METHOD

• US 20120060355A1
• Filed: 08/30/2011
• Published: 03/15/2012
• Est. Priority Date: 09/15/2010
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Tsuchikawa, Yutaka, Maeno, Takashi, Kuriyama, Naoto, Nakai, Takanori, Takeuchi, Hiromitsu, Kimura, Yoji
• Granted Patent: US 8,458,889 B2
• Time in Patent Office: Days
• US Class Current: 29/592.1
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2002/0894 Muscles non-implantable A61F2002/5066
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: H10N 30/05 Manufacture of multilayered piezoelectric or electrostrictive devices, or parts thereof, e.g. by stacking piezoelectric bodies and electrodes
• CPC Class Codes: H10N 30/067 Forming single-layered electrodes of multilayered piezoelectric or electrostrictive parts
• CPC Class Codes: H10N 30/506 of cylindrical shape with stacking in radial direction, e.g. coaxial or spiral type rolls
• CPC Class Codes: H10N 30/857 Macromolecular compositions
• CPC Class Codes: H10N 30/878 the principal material being non-metallic, e.g. oxide or carbon based
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49007 Indicating transducer
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49171 with encapsulating
• CPC Class Codes: Y10T 29/49176 with molding of electrically insulating material
• CPC Class Codes: Y10T 29/4922 with molding of insulation

Abstract

An actuator manufacturing method includes alternately stacking a plurality of dielectric elastomer layers and a plurality of conductive rubber layers along the direction of thickness to form a sheet, and wrapping the sheet formed about a core to form a rolled sheet. When the sheet formed in the step of alternately stacking is wrapped about the core, the sheet is formed by the dielectric elastomer layers and the conductive rubber layers. Therefore, even if the dielectric elastomer layers in the sheet are made to be thin, the thickness of the entire sheet is prevented from being excessively thin.

Claims

1. A method for manufacturing an actuator formed by rolling a sheet in which dielectric elastomer layers and conductive rubber layers are stacked along a direction of thickness, wherein, when voltage is applied to the conductive rubber layers in the sheet, the actuator expands the rolled sheet along an axial direction of the rolled sheet, and when the application of the voltage is stopped, the actuator contracts the rolled sheet along the axial direction, the method comprising;

alternately stacking a plurality of dielectric elastomer layers and a plurality of conductive rubber layers along a direction of thickness, thereby forming a single sheet; and

wrapping the sheet formed in the step of alternately stacking about a core, thereby obtaining a rolled sheet.

2. The method for manufacturing an actuator according to claim 1, wherein

some of the conductive rubber layers are connected to a positive terminal of a power source, and the other conductive rubber layers are connected to a negative terminal of the power source, and

the step of alternately stacking includes:

supplying the conductive rubber layers for being connected to the positive terminal of the power source that are stacked onto each other while being displaced in the same direction relative to the dielectric elastomer layers, and

supplying the conductive rubber layers for being connected to the negative terminal of the power source that are stacked onto each other while being displaced in the opposite direction to the direction in which the conductive rubber layers for being connected to the positive terminal of the power source are displaced relative to the dielectric elastomer layers.

3. The method for manufacturing an actuator according to claim 1, wherein, the step of alternately stacking includes

supplying one of the conductive rubber layers for being connected to a positive terminal of a power source that is formed on a front face of one of the dielectric elastomer layers, and one of the conductive rubber layers for being connected to a negative terminal of the power source that is formed on a back face of the dielectric elastomer layer, and

in this state, the dielectric elastomer layers and the conductive rubber layers are formed in a bellows-like manner, so that a plurality of the dielectric elastomer layers and a plurality of the conductive rubber layers are stacked onto each other in the direction of thickness to form a sheet.

4. The method for manufacturing an actuator according to claim 1, wherein the thickness of each dielectric elastomer layer for forming the sheet in the step of alternately stacking is determined such that, when a voltage is applied to the conductive rubber layers by the power source, the rolled sheet is expanded by a necessary amount.

5. The method for manufacturing an actuator according to claim 1, wherein the number of stacked layers in the step of alternately stacking is determined so as to obtain the minimum thickness of the sheet that allows the sheet to be wrapped about the core in the step of wrapping the sheet without tearing the layers.

6. The method for manufacturing an actuator according to claim 1, wherein the step of wrapping the sheet includes:

prior to wrapping of the sheet about the core, providing a coil spring on an outer circumferential surface of the core, and providing a pair of pipes on the outer circumferential surface of the core, each pipe being at one of both ends along the direction of expansion and contraction of the spring; and

removing the core from the rolled sheet after wrapping the sheet about the core, which has, on the outer circumferential surface thereof, the coil spring and the pipes.