TIRE INFLATION PRESSURE ESTIMATION DEVICE

摘要

PROBLEM TO BE SOLVED: To improve accuracy to estimate a target parameter in a tire inflation pressure estimation device that sequentially obtains base parameters to be used for estimating the target parameter (tire inflation pressure or parameter related thereto) based on a wheel speed signal which is output from a wheel speed sensor for detecting the rotating speed of a wheel (wheel with a tire), and estimate the target parameter based on a plurality of previously obtained base parameters including the last obtained one. SOLUTION: Base parameters correspond to dependant physical quantities. As a setting time T2 passes, during which those except for the tire inflation pressure are expected to change substantially, a target parameterΔKPRO1 corresponding to a variation of the spring constant is estimated based on M sets of base parameters. Each set comprises a rim side angular velocityωR a disturbanceω2 a belt side angular velocity (ωB, and a spiral angleθRB obtained during the latest setting time T2.