Method and apparatus for detecting ply defects in pneumatic tires
AssigneeThe Goodyear Tire & Rubber Company
InventorAlbert J. Yovichin
Life of this patent
Estimating the term…
Abstract
In a method and apparatus for detecting ply defects in a pneumatic tire, measurements on the tire are obtained at two levels of tire inflation, and the data obtained in the two measurements are compared. Broken reinforcement cords in the tire cause changes in the peaks of the data obtained at the two inflations that are out of proportion when compared to data changes observed in non-damaged tires. The apparatus of the invention provides means for inflating tires to predetermined pressures and has displacement sensors for measuring peaks and valleys in the sidewall of a tire. The apparatus may also include a computer for collecting data, analyzing data, and providing a signal when a defective tire is recognized.
Claims13
A method for detecting defects in a pneumatic tire comprising the steps of:
- (a) inflating said tire at a minimal pressure in the range of 0.5 to 10 psi, said pressure comprising a baseline pressure,
- (b) rotating said tire in proximity to a fixed displacement sensor, thereby obtaining a continuous baseline measurement around said tire,
- (c) inflating said tire 5 to 30 psi above said baseline pressure, said pressure comprising an elevated pressure,
- (d) rotating said tire in proximity to said fixed displacement sensor, thereby obtaining a continuous elevated pressure measurement around said tire, and
- (e) comparing the baseline measurement with the elevated pressure measurement and noting significant differences.
An apparatus for detecting defects in a pneumatic tire comprising
- (a) a base unit (14) having a rotatable mandrel (22) mounted thereon, said mandrel being adapted for holding a tire,
- (b) support means for supporting displacement sensors in the proximity of said tire attached to said base, said support means comprising a vertical support strut (16) attached to said base unit (14) and cross support (18) attached to said vertical support (16),
- (c) displacement sensor means (20, 20a) attached to said support means wherein support strut (16) is geared so that said cross support (18) moves up and down, and said cross support (18) has slides so that said sensor means can move laterally independently such that said sensor means can be moved up and down and side to side into the proximity of a tire sidewall when said tire is mounted on said mandrel, and
- (d) means for inflating said tire on said mandrel to a specific pressure and maintaining said pressure constant during testing.
Dependencies are inferred from the claim text.