Liquid state detecting sensor

摘要

A liquid state detecting sensor for detecting a state of a liquid including a liquid concentration detecting element (51), a holder member (55), and an enclosing member (41) as defined herein, wherein the holder member (55) has a configuration in which respective portions of a lower end surface facing the enclosed region are located higher than or at a same height as a lowest hole periphery at the rim of the element holding hole from which the detecting element protrudes, and at least one of circulation holes formed in the enclosing member is a bubble-discharging hole (41R) which has an upper end located higher than the lowest hole periphery and a lower end located lower than a surface peripheral edge of the lower end surface.