US 12,455,230 B2
Liquid deterioration determination device and hydraulic unit
Hikaru Seike, Osaka (JP); Hirokazu Nakamura, Osaka (JP); Mineo Inoue, Osaka (JP); and Kenji Ayado, Osaka (JP)
Assigned to DAIKIN INDUSTRIES, LTD., Osaka (JP)
Filed by DAIKIN INDUSTRIES, LTD., Osaka (JP)
Filed on Jan. 28, 2022, as Appl. No. 17/587,140.
Application 17/587,140 is a continuation of application No. PCT/JP2020/021176, filed on May 28, 2020.
Claims priority of application No. 2019-142188 (JP), filed on Aug. 1, 2019.
Prior Publication US 2022/0146412 A1, May 12, 2022
Int. Cl. G01N 21/31 (2006.01); G01N 33/28 (2006.01)
CPC G01N 21/31 (2013.01) [G01N 33/2888 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A liquid deterioration determination device comprising:
a liquid level gauge into which a liquid is introduced and that has translucency;
a casing attached to an outside of the liquid level gauge;
a light receiver provided integrally within the casing and configured to receive
detection light transmitted through a liquid introduced from a liquid tank of an external device or
detection light reflected by the liquid; and
an electronic control device configured to be operatively connected to the external device to determine a degree of deterioration of the liquid when the external device is in a stable operation state,
the light receiver being configured to output
a first detection value representing an amount of a light component of a first color included in the detection light transmitted through the liquid or the detection light reflected by the liquid and
a second detection value representing an amount of a light component of a second color included in the detection light transmitted through the liquid or the detection light reflected by the liquid, the second color being different from the first color,
the electronic control device being configured to determine the degree of deterioration of the liquid based on a ratio of the second detection value to the first detection value when the external device is in the stable operation state, and
the stable operation state of the external device being determined by referring to an operation time or a temperature rise of the liquid after starting an operation of the external device.