US 6,575,022 B1 · Engine crankcase gas blow-by sensor

Abstract

An engine crankcase gas blow-by sensor. In a closed crankcase ventilation system, crankcase gases are caused to flow through a venturi which includes high pressure and low pressure taps. The high and low pressure taps are coupled to a differential pressure transducer which produces an output that is proportional to the volumetric flow of crankcase gases through the venturi. The use of a venturi in conjunction with a differential pressure sensor offers a low resistance path for the flow of crankcase gases and allows continuous monitoring of blow-by without exceeding the operating pressure limitations of various oil seals. Such a sensor is particularly suited for closed crankcase ventilation (ccv) systems, as it doesn't require venting of crankcase gases to the atmosphere, but works well in open crankcase ventilation systems also.

Claims16

Dependent claims

An internal combustion engine, comprising:

at least one cylinder;
at least one piston slidingly disposed within the at least one cylinder in order to define a combustion chamber above the piston;
an air intake system operable to supply air to the combustion chamber;
a crankcase coupled to the at least one cylinder, wherein an interior of the crankcase is in fluid communication with an interior of the at least one cylinder below the at least one piston, wherein combustion gases which blow-by the at least one piston may enter the crankcase;
a venturi having an inlet port and an outlet port, wherein the inlet port is coupled to the crankcase interior and the outlet port is coupled to the air intake system such that gas within the crankcase may flow through the venturi;
a high pressure tap extending from an exterior of the venturi to an interior of the venturi;
a low pressure tap extending from the venturi exterior to the venturi interior;
and
a sensor coupled to the venturi and operative to measure a differential pressure between the high pressure tap and the low pressure tap.

6 more elements

Dependencies are inferred from the claim text.

Engine crankcase gas blow-by sensor

Life of this patent

Engine crankcase gas blow-by sensor

Life of this patent

Abstract

Claims16