Patent · US Expired

Method and apparatus for hard object detection

US5078645A · kind A · utility

8Cited by
10References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1990
Grant dateJan 7, 1992
Priority date
Expiry dateOct 26, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S56/15
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A thin film highly directional audible sound sensor is mounted within a rotatable feed roll of a forage harvester to detect the presence of stones and other hard foreign objects in a crop material being fed past the feed roll to a cutter mechanism. Air-borne sound waves produced by the impact of foreign objects on metal parts of the harvester are detected by the sensor which produces a signal for stopping the crop feed mechanism before the foreign objects reach the cutter mechanism. The sensor is mounted on a stationary support within the rotatable feed roll. Output signals from the sensor control a stop mechanism for the crop feed mechanism via conductors extending through a stationary support shaft for the feed roll, thereby avoiding the need to commutate output signals from the detector.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.