US 12,265,107 B2
Resistance detection sensor
Akira Nakatsu, Osaka (JP); and Kentaro Watanabe, Osaka (JP)
Assigned to PILLAR CORPORATION, Osaka (JP)
Filed by NIPPON PILLAR PACKING CO., LTD, Osaka (JP)
Filed on Jun. 5, 2023, as Appl. No. 18/329,314.
Claims priority of application No. 2022-105583 (JP), filed on Jun. 30, 2022.
Prior Publication US 2024/0003949 A1, Jan. 4, 2024
Int. Cl. G01R 27/08 (2006.01); G01N 27/06 (2006.01); G01R 27/22 (2006.01)
CPC G01R 27/22 (2013.01) [G01N 27/06 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A resistance detection sensor for detecting an electrical resistance value of a liquid, comprising:
a pair of electrodes immersed in the liquid;
a DC voltage application unit configured to apply a DC voltage having a first polarity between the pair of electrodes;
an AC voltage application unit configured to apply an AC voltage between the pair of electrodes; and
a control unit configured to calculate the electrical resistance value of the liquid, in a state where the DC voltage is applied between the pair of electrodes by the DC voltage application unit,
wherein the control unit controls the AC voltage application unit so as to apply an AC voltage starting from a second polarity opposite to the first polarity at a predetermined time interval between the pair of electrodes, and
a time period for which the AC voltage is applied between the pair of electrodes by the AC voltage application unit is not an integer multiple of a cycle of the AC voltage that is applied between the pair of electrodes.