US 11,850,538 B2
Filter life predicting apparatus
Nobuyuki Kitajima, Kanagawa (JP); and Nobuki Sasaki, Kanagawa (JP)
Assigned to YAMASHIN-FILTER CORP., Kanagawa (JP)
Filed by YAMASHIN-FILTER CORP., Kanagawa (JP)
Filed on Jun. 2, 2021, as Appl. No. 17/336,983.
Application 17/336,983 is a continuation of application No. PCT/JP2019/046956, filed on Dec. 2, 2019.
Claims priority of application No. 2018-231947 (JP), filed on Dec. 11, 2018.
Prior Publication US 2021/0285803 A1, Sep. 16, 2021
Int. Cl. B01D 35/143 (2006.01)
CPC B01D 35/143 (2013.01) 6 Claims
OG exemplary drawing
 
1. A filter life predicting apparatus comprising:
a differential pressure detector provided in a filtration device including a filtration member that filters a liquid, the differential pressure detector detecting a differential pressure as a pressure difference between a high pressure side and a low pressure side in the filtration device;
a storage that stores differential pressure characteristics, the differential pressure characteristics indicating a relationship between the differential pressure and an attached dust amount as an amount of dust attached to the filtration member, the differential pressure characteristics including information on a life of the filtration member; and
a life predicting unit comprising a processor,
wherein the differential pressure detection unit includes a spool, a magnet, a magnetic flux density detection element, and a correction unit, the spool is displaced according to the pressure difference, the magnet is provided on the spool, the magnetic flux density detection element detects a change in a magnetic flux density based on an amount of displacement of the magnet and outputs a first voltage according to the change in the magnetic flux density, and the correction unit corrects the first voltage into a second voltage proportional to the pressure difference, and
the life predicting unit obtains the remaining life based on the second voltage;
wherein the life predicting unit obtains a remaining life based on a first differential pressure detected by the differential pressure detector at a first time as a time while the filtration device filters the liquid and the differential pressure characteristics, the remaining life indicating how long the filtration member is usable after the first time;
wherein the differential pressure detector continuously detects the differential pressures, and
the life predicting unit continuously obtains remaining lives based on the continuously detected differential pressures to correct the remaining life based on obtained results; and
wherein the life predicting unit obtains a first remaining life and a second remaining life as the remaining lives, the first remaining life indicating how long the filtration member is usable after the first time, the second remaining life indicating how long the filtration member is usable after a second time based on a second differential pressure detected by the differential pressure detector at the second time prior to the first time and the differential pressure characteristics, and
the life predicting unit corrects the differential pressure characteristics based on an elapsed time between the second remaining life and the first remaining life in the differential pressure characteristics and an elapsed time between the second time and the first time, and corrects the first remaining life based on the corrected differential pressure characteristics.