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:
Jan. 29, 1980
Filed:
Oct. 20, 1978
John K McVey, Bensenville, IL (US);
Illinois Tool Works Inc., Chicago, IL (US);
Abstract
A radial lead thermal cut-off device for opening an electrical circuit when a predetermined temperature is disclosed. Electrical connection between the radial leads is maintained by thin spring contact which is forced against the terminal heads of the leads of the device. The spring contact is forced into contact by a disc against the force of a coiled bias spring that engages the center of the spring contact. The disc is held in place by a temperature-sensing pellet of organic material which melts at a predetermined temperature and which preferably incorporates a multitude of spherical glass beads filling that greatly increase its strength. The pellet has a centrally located cavity so that when the organic material of the pellet melts the material fills a volume having a smaller transverse dimension. This allows the disc to move as the compression force of the coiled spring is relieved, which in turn opens the circuit between the contact members as the thin spring contact is forced away from the lead heads by the coiled spring.