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:
Mar. 28, 1995
Filed:
Dec. 14, 1993
Edwin C Ballard, Rehoboth, MA (US);
Andrew A Amatruda, Jr, Attleboro, MA (US);
Sheldon S White, Brookline, MA (US);
Other;
Abstract
A snap acting control member (10, 10b) having high actuating temperatures comprises metal layers metallurgically bonded together with a low expansion (12) and a relatively high expansion layer (14) each having similar moduli of elasticity and the low expansion layer being formed of a precipitation hardenable stainless steel so that after forming into a dished shaped configuration to make the member snap acting the low expansion layer is heat treated to increase the strength. The control member can be used solely to sense temperature or it can be used as an electrical current carrying member. When used in the latter manner, the electrical resistivity of the member can be adjusted by interposing a selected layer (16) between layers (12) and (14) to thereby increase or decrease the resistivity of the member (10b) depending on the particular metal chosen for the interlayer. An electrical switch (24) is shown in which a snap acting member is used as a sensor and another electrical switch (48) is shown in which the snap acting member is a current carrying member.