Method and device for the correction of the zero point of the pressure sensor of a hydraulic power steering system

摘要

PURPOSE: To correct a zero pressure value to an accurate value each time an engine is stopped by detecting the working pressure of a power steering after an engine is stopped, adding the number of detecting times when the working pressure is not changed for a specified time, and setting a working pressure, at which the number of detecting times is maximized, to a zero pressure value. ;CONSTITUTION: After the stop of drive of an engine 14, the working pressure of a power steering is detected by means of the pressure sensors 9 and 10 of a power steering 1. The number of detecting times of a working pressure is added on a condition that the working pressure is not changed for a specified time and data on the number of detecting times at each steering working pressure is provided in the memory of a microcomputer 11. A working pressure at which the so obtained number of detecting times is increased to a maximum value is employed as the zero pressure values of the pressure sensors 9 and 10. As noted above, each time drive of the engine 14 is stopped, the zero pressure value is corrected to an accurate value and the neutral point of a steering handle is adjusted to an accurate value.;COPYRIGHT: (C)1993,JPO&Japio