Patent ID: 6105557
Filing Date: 2000-08-22
Classification: F02M

Abstract:
A method for checking the operability of a tank-venting system, the tank-venting system including a tank, an adsorption filter having a tank-venting line, a connecting line for connecting the adsorption filter to the tank, a tank-venting valve and a valve line connecting the adsorption filter to the tank-venting valve, the method comprising the steps of:providing a pressure source for introducing a pressure into said tank-venting system;connecting reference leak means in parallel to said tank-venting system;detecting an operating characteristic variable of said pressure source only over a pregiven time interval (.DELTA.t.sub.m) when introducing said pressure to obtain a time-dependent trace of said operating characteristic variable; and,alternately applying pressure to said reference leak means and detecting said operating characteristic variable while introducing said pressure into said reference leak means to obtain a first time-dependent trace of said operating characteristic variable and to said tank-venting system and detecting said operating characteristic variable while introducing pressure into said tank-venting system to obtain a second time-dependent trace of said operating characteristic variable; and,extrapolating and comparing said first and second time-dependent traces to each other and drawing a conclusion as to the presence of a leak in said tank-venting system from the comparison.