Prediction and control of mass unbalance and high speed uniformity

Abstract

Technology is disclosed for characterizing both mass uneven distribution and high speed uniformity of a tire. Mass uneven distribution is identified from analysis of at least two radial run out (RRO) measurements, wherein a first RRO measurement is obtained for a relatively high speed of at least about 600 rotations per minute. A second RRO measurement may be at a relatively low speed less of at most about 180 rotations per minute if the effects of radial stiffness variation on the RRO is mall. If the effects of radial stiffness variation on the RRO can not be neglected, a third RRO at another high speed of at least above 600 rotations per minute is needed. RRO measurements are then decomposed into a plurality of harmonics and mass uneven distribution coefficients are calculated for the respective harmonics. The mass uneven distribution coefficients are then used to determine size and location of any mass unbalance, including mass uneven distribution and / or point mass. Mass unbalance characterization can be further applied to tire sorting processes and improvements to tire manufacturing. Measurement and analysis of tire high speed radial run out can also be coupled with low speed force measurements to determine and characterize tire high speed uniformity. Tire high speed uniformity characterization can also be applied to tire sorting processes and corresponding tire manufacturing process improvement, for example, in control and optimization of tire layer overlap or variation parameters.

Description

FIELD OF THE INVENTION [0001] The present invention generally concerns technology for characterizing tire performance parameters, such as mass unbalance including mass uneven distribution, and high speed uniformity. Characterization and prediction of such tire parameters and others may subsequently be used to sort manufactured products and / or control manufacturing aspects thereof. BACKGROUND OF THE INVENTION [0002] Many vehicle vibrations typically become detectable to a driver at typical highway road speeds in excess of 25 mph. One exemplary cause of vehicle vibration at relatively high speeds corresponds to force variations at respective tire spindle locations which is typically referred to as tire high speed uniformity. [0003] High speed uniformity (HSU) has become a growing concern in the automobile industry, and thus many tire manufacturers are being pressured to implement HSU control. Tire HSU measurement, however, has been difficult and quite costly, making HSU industrial con...

AI Technical Summary

Benefits of technology

This approach enables effective prediction and control of tire high speed uniformity, improving manufacturing processes by sorting and grading tires based on mass unbalance and uniformity, reducing vehicle vibrations and manufacturing costs.

Problems solved by technology

Many vehicle vibrations typically become detectable to a driver at typical highway road speeds in excess of 25 mph.

Tire HSU measurement, however, has been difficult and quite costly, making HSU industrial control very difficult.

There are many contributing factors to tire HSU, and thus one of the biggest challenges in effectively controlling HSU lies in being able to properly identify such contributing factors in order to control corresponding levels of tire force variation and vehicle vibration.

The previous attempts at predicting tire HSU parameters referenced above do not account for mass uneven distribution as a factor in predicting and controlling high speed uniformity.

Although known technology for characterizing tire high speed uniformity and affecting associated aspects of tire manufacturing have been respectively developed, no design has emerged that generally encompasses all of the desired characteristics as hereafter presented in accordance with the subject technology.

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