초록 ▼

An improved diagnosis apparatus for detecting leakage of a fuel vapor purge system that purges fuel vapor from a fuel tank to an intake passage of an engine. The apparatus includes a pressure sensor and a purge valve. The pressure sensor detects the pressure in the purge system. The purge valve conn

An improved diagnosis apparatus for detecting leakage of a fuel vapor purge system that purges fuel vapor from a fuel tank to an intake passage of an engine. The apparatus includes a pressure sensor and a purge valve. The pressure sensor detects the pressure in the purge system. The purge valve connects the purge system with the intake passage for lowering the purge system pressure to a predetermined pressure level. After the purge system pressure is lowered to the predetermined level, the purge system is sealed. The apparatus measures the rate of pressure change immediately after the purge system is sealed. The apparatus subsequently measures the rate of pressure change when the purge system pressure reaches a second reference pressure value and computes the ratio of the rates. The apparatus diagnoses whether there is a leak in the purge system based on the ratio and the rate of pressure change at the second reference pressure value.

대표청구항 ▼

An improved diagnosis apparatus for detecting leakage of a fuel vapor purge system that purges fuel vapor from a fuel tank to an intake passage of an engine. The apparatus includes a pressure sensor and a purge valve. The pressure sensor detects the pressure in the purge system. The purge valve conn

An improved diagnosis apparatus for detecting leakage of a fuel vapor purge system that purges fuel vapor from a fuel tank to an intake passage of an engine. The apparatus includes a pressure sensor and a purge valve. The pressure sensor detects the pressure in the purge system. The purge valve connects the purge system with the intake passage for lowering the purge system pressure to a predetermined pressure level. After the purge system pressure is lowered to the predetermined level, the purge system is sealed. The apparatus measures the rate of pressure change immediately after the purge system is sealed. The apparatus subsequently measures the rate of pressure change when the purge system pressure reaches a second reference pressure value and computes the ratio of the rates. The apparatus diagnoses whether there is a leak in the purge system based on the ratio and the rate of pressure change at the second reference pressure value. first shear rate for generating plural shear rates; and a computer for statistically analyzing said data relating to the changing weight to determine if there is good or poor mixing of the fluid mixture. 2. The apparatus of claim 1 wherein said computer uses standard deviation to calculate the disparity of said data from a reference line in order to determine if there is good or poor mixing. 3. A method for determining the online homogeneity of a fluid mixture flowing through a process, said method comprising the steps of: (a) providing a lumen having a first end and a second end and positioned at an angle to a horizontal reference greater than zero degrees, said first end being coupled to said process; (b) coupling an inlet of a flow restrictor, having an outlet, to said second end of said lumen; (c) disposing said lumen and said flow restrictor on a mass detector and positioning said outlet to deliver any fluid flowing through said outlet into a collector; (d) diverting a predetermined amount of said fluid mixture from the process into said lumen and said flow restrictor and to collect in said collector to form a continuous non-moving sample of fluid mixture occupying said lumen and said flow restrictor, said step of diverting establishing a pressure differential between said first end and said outlet; (e) obtaining an initial weight of said lumen and said flow restrictor by said mass detector; (f) exposing said first end to atmospheric pressure to cause said sample of fluid mixture to move through said lumen and said flow restrictor at a first shear rate caused by said pressure differential, said movement of fluid causing said pressure differential to decrease from said first shear rate for generating plural shear rates; (g) detecting the changing weight of said lumen and said flow restrictor over time as said sample of fluid mixture passes through said outlet into said collector to form weight data over time; and (h) statistically analyzing said weight data to determine if there is good or poor mixing of the fluid mixture. 4. The method of claim 3 wherein said step of statistically analyzing said weight data comprises using standard deviation to calculate the disparity of weight data from a reference line for determining if there is good or poor mixing.