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. 17, 1991
Filed:
Dec. 15, 1988
Hannu Kulju, Hyvinkaa, FI;
Kone Elevator GmbH, Baar, CH;
Abstract
The invention relates to a procedure and apparatus for detecting and counting objects having velocities and that are in a certain area, wherein at least one passive detector detects background radiation, the signal obtained from said detector is amplified to produce a second signal independent of the distance and size of the object. The frequency content of this second signal is analyzed to chart the movements of the objects. To produce an inexpensive and simple detector, detection of movement of each object and generation of a signal with a frequency content are achieved by dividing the change in background radiation caused by each object into a succession of flashes hitting a surface capable of detecting the background radiation, so that the detector provides an electrical signal the frequency of which is characteristic of the velocity of each object and changes in proportion to the change in the velocity of each object.