US 11,731,166 B2
Detection system
Claes Larsson, Bjärred (SE)
Assigned to Metso Sweden AB, Trelleborg (SE)
Filed by METSO SWEDEN AB, Trelleborg (SE)
Filed on Dec. 7, 2021, as Appl. No. 17/544,205.
Application 17/544,205 is a continuation of application No. 16/345,322, granted, now 11,224,897, previously published as PCT/EP2017/077656, filed on Oct. 27, 2017.
Claims priority of application No. 16196333-5 (SE), filed on Oct. 28, 2016.
Prior Publication US 2022/0088640 A1, Mar. 24, 2022
Int. Cl. B07B 1/42 (2006.01); B06B 1/16 (2006.01); B07C 1/00 (2006.01); B07C 5/34 (2006.01); B07C 5/36 (2006.01)
CPC B07B 1/42 (2013.01) [B06B 1/16 (2013.01); B07C 1/00 (2013.01); B07C 5/34 (2013.01); B07C 5/36 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A detection system for use in a screening device for screening material, the screening device including at least one screening deck including a plurality of screening modules which together define a screening surface of the screening device, the system comprising:
an ultrasound sensor arranged at or near the least one screening deck of the screening device, the ultrasound sensor having a sensing range such that the ultrasound sensor is operable to detect objects leaving the at least one screening deck that are in the sensing range, wherein the ultrasound sensor is operable to generate a sensing signal when objects are in the sensing range; and
a control unit in communication with the ultrasound sensor to receive the sensing signal from the ultrasound sensor based on the detection of objects leaving the at least one screening deck that are in the sensing range,
wherein the control unit is operable to determine an amount of time the sensing signal is received from the ultrasound sensor and apply one or more predefined threshold values that are based on a time an object is present in the sensing range of the ultrasound sensor to differentiate between signals resulting from the material to be screened and signals resulting from a foreign object.