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:
Jul. 24, 1990
Filed:
Jan. 25, 1989
Thomas J Holce, Portland, OR (US);
Keith E Flint, Portland, OR (US);
Sentrol, Inc., Portland, OR (US);
Abstract
A magnetically actuated reed switch assembly in which a small permanent helper magnet is attached to a magnetic lead of the reed switch at an end of the reed switch envelope. The lead then may be bent around parallel with a magnetic reed of an encapsulated reed switch. The permanent helper magnet provides an axis of magnetic polarity parallel with the axis of the reed switch, and is magnetized to a level of magnetism which supplies slightly less than enough magnetic flux density to hold the reed switch in a magnetically actuated condition, so that only a small amount of additional flux density needs to be provided. By selecting reed switches within close tolerances and using helper magnets of selected size and strength within close tolerances, satisfactory assemblies may be produced without adjustment of helper magnet position to actuate the switch. The small permanent magnet may alternatively define a bore fitting around the magnetic lead, and may be magnetized after assembly of the magnet and magnetic lead of the switch, thus reducing the amount of time and labor required to manufacture the switch assembly.