Method for detecting low level of paste product in feeding box of pump, comprises means to make ultrasonic transmitter/receiver active only when forcing and smoothing bar is at low point of travel

摘要

A pasty product fed to the feeding box of a pump (1) is impelled toward the pump by a U shaped forcing and smoothing bar (7) on a rotating shaft (9) and a helical spiral (4). An ultrasonic beam (12) and transmitter/receiver (11) is activated only when the bar is at the bottom of it's travel and signals indicating levels above and below a threshold are only considered valid when the ultrasonic equipment is functional. An independent claim is also included for a feeding box for supplying a pump with a paste product which has a U shaped forcing and smoothing bar and an ultrasonic transmitter/receiver activated only when the bar is at the low point of travel.