Fluid Quality Sensing Means with Reference Sensor

摘要

A sensing apparatus for detecting fluid quality change using signals obtained from a fluid quality sensor for exposure to a fluid and a reference sensor positioned in a reference sensing means having a fluid trap section holding a part of the fluid. Sensing values obtained from the fluid quality sensor and the reference sensor are compared in determining an aging factor. An application of the sensing apparatus is an apparatus for detecting engine oil quality change in an engine system. With the sensing apparatus, a first aging factor can be calculated after an engine cold soak and a second one can be obtained during engine operation. With these two aging factors, in addition to oil quality change, failures in the engine system and sensors, and oil change events can also be detected. Additionally, since reference sensing values are provided by the reference sensor, power disconnections have least effects.

主权项

1. An apparatus for measuring fluid quality and degradation in a fluid system, comprising:
a fluid container containing a system fluid being used in said fluid system; a fluid filler passage including a fluid trap section holding a reference fluid, which is refreshed every time said system fluid is filled into said fluid container; a first sensor generating a first sensing signal indicative of at least one property of said reference fluid being held in said fluid trap section; a second sensor generating a second sensing signal indicative of said at least one property of said system fluid in said fluid container; and a controller configured to generate a fluid quality signal indicative of a quality of said system fluid in response to said first sensing signal and said second sensing signal.