Article using shape-memory alloy to improve and/or control the speed of recovery

• US 4,759,293 A
• Filed: 06/17/1987
• Issued: 07/26/1988
• Est. Priority Date: 06/30/1986
• Status: Expired due to Fees

• Current Assignee: Thomas O. Davis Jr
• Original Assignee: Thomas O. Davis Jr
• Inventors: Davis, Thomas O. Jr.
• Primary Examiner(s): BROWN, DAVID
• Application Number:
  US07/058,886
• Time in Patent Office: 405 Days
• Field of Search: 102/520, 102/521, 102/522, 102/523, 102/532
• US Class Current: 102/520
• CPC Class Codes: F42B 12/34 expanding before or on impact, i.e. of dumdum or mushroom type
• CPC Class Codes: H01H 35/14 Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch wherein the liquid constitutes a contact of the switch H01H29/002
• CPC Class Codes: H01H 61/0107 making use of shape memory materials

Abstract

An article in the form of a projectile, a shock-sensitive switch or a sabot having an active component of shape-memory alloy which exhibits the shape-memory effect to provide a mechanical movement in response to a pressure wave passing through the article is disclosed. A thermal enhancement component which rapidly generates heat to initiate the shape-memory effect is also disclosed.

Claims

1. A sabot comprising:

a plurality of body sections, said sections forming a cylinder having first and second ends, said sections pivotal with respect to each other at said first end of said cylinder in order to move the sections radially away from each other at said second end of the cylinder;

a ring of shape-memory alloy surrounding said sections near said first end of said cylinder, said shape-memory alloy having a martensitic state and an austenitic state, said ring being dimensionally deformed and radially expanded to surround said sections while said shape-memory alloy is in its martensitic state, a change from its martensitic state to its austenitic state recovering said ring to its non-deformed dimension due to the shape-memory effect exhibited by said alloy to pivot and to separate said sections;

thermal enhancement means in operative thermal contact with said ring, said thermal enhancement means comprising a material containing voids, collapse of said voids generating heat; and

a pusher-plate in contact with said thermal enhancement means, said pusher-plate movable upon acceleration of the sabot, enabling said pusher-plate to crush the thermal enhancement means causing recovery of the ring and separation of the sections.