Fibrous parallel spring-loaded shape memory alloy rebotic linear

• US 5,821,664 A
• Filed: 03/28/1997
• Issued: 10/13/1998
• Est. Priority Date: 03/28/1996
• Status: Expired due to Fees

• Current Assignee: Mohsen Shahinpoor
• Original Assignee: New Mexico State University
• Inventors: Shahinpoor, Moshen
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US08/829,535
• Time in Patent Office: 564 Days
• Field of Search: 148/402, 310/307
• US Class Current: 310/307
• CPC Class Codes: F03G 7/065 using a shape memory element

Abstract

Shape memory alloy actuators comprising at least one hollow helical spring with an array of parallel shape memory alloy wires enclosed within or parallel and attached to each of the at least one hollow helical springs. Insulative end caps are attached to end of the at least one hollow helical springs, the insulative end caps defining electrodes for conducting electricity to the arrays of parallel shape memory alloy wires. Voltage means are connected to the electrodes for selectively providing electrical energy to the parallel array of shape memory alloy wires, causing the parallel array of shape memory alloy wires to expand and contract, providing either motion or measurement functions. In one embodiment, at least three helical springs with an array of parallel shape memory alloy wires either enclosed within or situated in physical and electrical contact with each of the at least three helical springs are enclosed within the insulative end caps and are individually actuated to provide three-dimensional movement to the insulative end caps.

Claims

1. A shape memory alloy actuator comprising;

at least one hollow helical spring;

an array of parallel shape memory alloy wires enclosed within each of said at least one hollow helical springs;

insulative end caps attached to each end of each of said at least one helical springs, said insulative end caps defining electrodes for conducting electricity to said arrays of parallel shape memory alloy wires;

voltage means connected to said electrodes for selectively providing electrical energy to said parallel array of shape memory alloy wires, causing said parallel array of shape memory alloy wires to expand and contact.

2. The shape memory alloy actuator as described in claim 1, wherein said at least one helical spring comprises one spring.

3. The shape memory alloy actuator as described in claim 1, further comprising one-way cilia attached to said insulative end caps.

4. The shape memory alloy actuator as described in claim 1, wherein said array of parallel shape memory alloy wires comprise NITINOL®

wires.

5. The shape memory alloy actuator as described in claim 1, wherein said at least one helical spring comprises at least three helical springs with an array of parallel shape memory alloy wires enclosed within each of said at least three helical springs said at least three helical springs and said array of parallel shape memory alloy wires being individually actuated to provide three-dimensional movement to said insulative end caps.

6. A shape memory alloy actuator comprising:

at least one helical spring;

an array of parallel shape memory alloys wires situated in physical and electrical contact with each of said at least one helical spring;

insulative end caps attached to each end of each of said at least one helical springs, said insulative end caps defining electrically conductive electrodes for conducting electricity said arrays of shape memory alloy wires; and

voltage means connected to said electrodes for selectively providing electrical energy to said parallel array of shape memory alloy wires, causing said parallel array of shape memory alloy wires to expand and contact.

7. The shape memory alloy actuator as described in claim 6, wherein said at least one helical spring comprises one spring.

8. The shape memory alloy actuator as described in claim 6, further comprising one-way cilia attached to said insulative end caps.

9. The shape memory alloy actuator as described in claim 6, wherein said array of parallel shape memory alloy wires comprise NITINOL®

wires.

10. The shape memory alloy actuator as described in claim 6, wherein said at least one helical spring comprises at least three helical springs with an array of parallel shape memory alloy wires situated in physical and electrical contact with each of said at least three helical springs said at least three helical springs and said array of parallel shape memory alloy wires being individually actuated to provide three-dimensional movement to said insulative end caps.