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:
Dec. 20, 1983
Filed:
May. 21, 1981
Eldon Nerheim, Hopkins, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A proximity monitor for movement at a selected distance from a surface, including a first microwave sensor having an antenna pattern directed toward the surface, the principal component of the pattern parallel to the surface being in the direction of the movement, a second microwave sensor having a second antenna pattern directed toward the surface, the principal component of the second pattern parallel to the surface being at a direction opposite to that of the movement, and the patterns being mutually spaced at the surface in the direction of movement, a magnetic anomaly sensor giving an output representative of the presence at the surface of a magnetic anomaly located between the patterns, and apparatus connected to the sensors for performing a control function when the signals from the sensors are above predetermined levels in a predetermined time relationship.