The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 30, 1995
Filed:
Dec. 10, 1993
Applicant:
Inventors:
Paul E Thoma, Cedarburg, WI (US);
Ming-Yuan Kao, Fox Point, WI (US);
Dwight M Schmitz, West Allis, WI (US);
Assignee:
Johnson Service Company, Milwaukee, WI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ; C22F / ;
U.S. Cl.
CPC ...
148402 ; 148421 ; 148563 ; 420902 ;
Abstract
The present invention relates to a method for increasing the useful life of a shape memory alloy (SMA) actuator, wherein the SMA element contracts on heating and elongates on cooling under an applied stress and that property is used as an actuating technique. More specifically, the present invention relates to the cooling aspect of the cycle and maintaining a martensite strain on the actuator SMA element at less than about 3% by limiting the upper stress on the element. In the most preferred embodiment, the element is a ribbon actuator prepared from a nickel-titanium SMA alloy.