Patent ID: 6477446
Filing Date: 2002-11-05
Classification: F16D,F16H,F16K,G05D

Abstract:
A method of conforming to varying parameters a selected electric control current which is being supplied to a fluid pressure regulating valve and is memorized with additional control currents as a desired control current in and is withdrawable from a characteristic field in a memory, in dependency upon prevailing operating conditions, to serve as an actual control current, comprising the steps of:superimposing upon the actual control current a modulating current having a predetermined modulation amplitude; ascertaining a fluctuation amplitude of the fluid pressure which is brought about by the modulating current; comparing the ascertained fluctuation amplitude with a predetermined fluctuation amplitude; and correcting the characteristic field upon detection of a departure of the ascertained fluctuation amplitude from the predetermined fluctuation amplitude in a sense to reduce the extent of said departure, wherein the modulating current is an alternating current with a single predetermined oscillation frequency and said superimposing step includes superimposing the modulating current in the course of several oscillation periods, and wherein the method further comprises the step of averaging the amplitudes of signals being transmitted by a fluid pressure sensor during said several oscillation periods, and carrying out said correcting step as a function of the averaged signal amplitude.