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:
Jun. 17, 1980
Filed:
Sep. 07, 1978
John K McVey, Chicago, IL (US);
Bruce A Luxon, Bensenville, IL (US);
Illinois Tool Works Inc., Chicago, IL (US);
Abstract
A thermal switch for automatically opening a circuit when the ambient temperature exceeds a predetermined level is disclosed which utilizes a sensing pellet formed of an organic-glass bead mixture. The organic-glass bead pellet retains a pair of leads in contact with each other when the ambient temperature is below the melting temperature of the organic material. The addition of the glass beads to the temperature sensing pellet allows the compressive strength that is needed to hold the leads together to be more reliably controlled. In the process of combining the organic material and the glass beads, to form the pellet, the organic material is first melted so as to flow around the beads. Manufacture of the thermal-sensing pellet in this manner eliminates the voids which occur in the pressed organic pellets that are conventionally used in thermal sensing devices. The elimination of these voids increases the strength of the otherwise relatively fragile pellet thereby improving reliability of thermal switches which utilize the improved pellet of the present invention.