US 12,480,903 B2
Liquid state detection sensor
Yuki Nagai, Kanagawa (JP); Yukinori Kameda, Kanagawa (JP); Takahiro Yoshida, Kanagawa (JP); and Ryohei Nakamura, Kanagawa (JP)
Assigned to KYB CORPORATION, Tokyo (JP)
Appl. No. 18/259,502
Filed by KYB Corporation, Tokyo (JP)
PCT Filed Dec. 20, 2021, PCT No. PCT/JP2021/047017
§ 371(c)(1), (2) Date Jun. 27, 2023,
PCT Pub. No. WO2022/145273, PCT Pub. Date Jul. 7, 2022.
Claims priority of application No. 2020-218839 (JP), filed on Dec. 28, 2020; and application No. 2021-029516 (JP), filed on Feb. 26, 2021.
Prior Publication US 2024/0060923 A1, Feb. 22, 2024
Int. Cl. G01N 27/07 (2006.01); G01N 27/08 (2006.01); G01N 27/10 (2006.01); G01N 33/28 (2006.01)
CPC G01N 27/07 (2013.01) [G01N 27/08 (2013.01); G01N 27/10 (2013.01); G01N 33/2888 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A liquid state detection sensor configured to detect a state of a liquid, the liquid state detection sensor comprising:
an electrode part arranged in a flow passage of the liquid, the electrode part having a pair of electrodes provided so as to be opposed to each other;
a voltage value acquisition time period setting unit configured to set a voltage value acquisition time period, the voltage value acquisition time period being a length of a time period during which an inter-electrode voltage value of the pair of electrodes of the electrode part is acquired;
a voltage value acquisition unit configured to acquire the inter-electrode voltage value (N+1) times at the same interval during the voltage value acquisition time period, where N is a natural number greater than zero; and
an electrical conductivity calculation unit configured to calculate an electrical conductivity of the liquid based on, among the (N+1) inter-electrode voltage values acquired by the voltage value acquisition unit, the inter-electrode voltage values acquired after a predetermined time period has elapsed, wherein
the electrical conductivity calculation unit is further configured to:
obtain the inter-electrode voltage value at each of an Nth time and an (N+1)th time from the voltage value acquisition unit;
determine whether a difference between the inter-electrode voltage values at the Nth time and the (N+1)th time falls within a predetermined range, the predetermined range being a range of an attenuation level corresponding to a case in which the inter-electrode voltage value follows an expected attenuation behavior; and
in response to determining that the difference falls within the predetermined range, set the predetermined time period as a time period from a start of the voltage value acquisition time period to a time of the (N+1)th time; and
calculate the electrical conductivity of the liquid using inter-electrode voltage values acquired by the voltage value acquisition unit after the (N+1)th time.