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. 05, 1996
Filed:
Oct. 13, 1993
Toshio Shimada, Tochigi, JP;
Wataru Sugawara, Tochigi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An overload protective apparatus has fixed contacts connected to at least one pair of fixed terminals secured on the bottom of a case, a dish-shaped polymetallic element, e.g., a bimetal or trimetal having movable contacts bonded thereon so as to oppose the fixed contacts, and an adjusting bolt supporting a central portion of the polymetallic element for maintaining the polymetallic element at a position separate from the bottom of the case, wherein the polymetallic element and the adjusting bolt are accommodated in the case. The polymetallic element used herein is constructed to make a current density around bonding portions for the movable contacts higher than other regions, such that portions around the movable contacts are more susceptible to rupture when an abnormal current flows through the polymetallic element. The polymetallic element is also constructed to prevent degradation of the spring constant thereof.