Apparatus and related methods for automatically testing and analyzing tires utilizing a test pod with a slidably movable cover plate and a gray scale normalization technique

US5777219A · kind A · utility

Assignee

• Bridgestone Firestone · US

Inventors

• James A. Popio · Mogadore, US
• John L. Turner · Tucson, US
• Richard J. Macioce · Massillon, US
• Wayne A. Indorf · Canton, US
• Fu-Min CHEN · Tallmadge, US
• Stanley J. Olesky · Akron, US
• Vladimir Roth · Akron, US

Key dates

• Filing date: Oct 16, 1996
• Grant date: Jul 7, 1998
• Expiry date: Oct 16, 2016

Classification

• Technology area (CPC G): Physics
• CPC primary: G01M17/027
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An apparatus and related methods for capturing a digital foot print image of a tire and for extrapolating load-deflection curves of the tire is presented. A frame carries a test pod that is coupled to a tire to perform various tests. In one application, a loading plate couples the tire to a transparent plate on the test pod where a camera captures a digital gray-scale image of the tire foot print. A processor converts the gray-scale image into a pressure map wherein each pixel of the digital image is correlated to a pressure value. In another application, the loading plate couples the tire to a sliding cover plate on the test pod, wherein the loading plate is incremented through a plurality of load values at predetermined inflation pressures. By using two inflation pressures, the processor extrapolates further load-deflection curves for the tire at other inflation pressures. The apparatus also provides a unique way for imparting camber on the tire during the above tests. The data collected from the foot print image and load-deflection curves may be used to analyze the construction, operation, noise generation characteristics and performance of the tire.