Method of foreseeing tread wearing of a pneumatic tire
First Claim
1. A method of foreseeing wear of a tread band in a pneumatic tire for vehicle wheels, said method comprising the steps of:
- a) forming a plurality of radial cuts in at least one portion of a radially external surface of said tread band, a first plurality of portions of said at least one portion lying between pairs of adjacent said cuts, said tread band comprising an internal band portion which directly underlies said at least one portion to be radially more internal relative to the at least one portion, said cuts of said at least one portion extending at most through a depth of said at least one portion, said internal band portion comprising a second plurality of portions which are not cut, wherein each portion of said second plurality of portions underlies a respective one of each of said first plurality of portions, the depth, width and mutual distance between said cuts being such that each portion of said first plurality of portions is immobile relative to the respective underlying portion of said second plurality of portions while the tire is being rotated;
b) rotating the tire at a predetermined speed and with a predetermined load in contact with a friction surface, said cuts not performing any function as regards road holding of the tire;
c) stopping the rotating of the tire;
d) verifying wearing of said at least one tread band portion through observation of disappearing of said radial cuts after the tire has stopped.
2 Assignments
0 Petitions
Accused Products
Abstract
A method of foreseeing and controlling wearing in the tread of a tire based on the use of cuts of a limited depth (in the order of tenth parts of one millimeter) formed on the external surface of the tread, in the thickness of the elastomeric material. The cut is preferably made by a laser beam. Rotation of the tire on a road or on any other friction surface enables both the uneven wearing of the tread, highlighted by localized spots devoid of cuts, to be quickly verified by inspecting the maintenance state of the cuts. Also, and the wear rate of the tread can be drawn from calculation of the time, during the rotation, elapsing between the disappearance of two groups of cuts of different depth.
34 Citations
34 Claims
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1. A method of foreseeing wear of a tread band in a pneumatic tire for vehicle wheels, said method comprising the steps of:
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a) forming a plurality of radial cuts in at least one portion of a radially external surface of said tread band, a first plurality of portions of said at least one portion lying between pairs of adjacent said cuts, said tread band comprising an internal band portion which directly underlies said at least one portion to be radially more internal relative to the at least one portion, said cuts of said at least one portion extending at most through a depth of said at least one portion, said internal band portion comprising a second plurality of portions which are not cut, wherein each portion of said second plurality of portions underlies a respective one of each of said first plurality of portions, the depth, width and mutual distance between said cuts being such that each portion of said first plurality of portions is immobile relative to the respective underlying portion of said second plurality of portions while the tire is being rotated; b) rotating the tire at a predetermined speed and with a predetermined load in contact with a friction surface, said cuts not performing any function as regards road holding of the tire; c) stopping the rotating of the tire; d) verifying wearing of said at least one tread band portion through observation of disappearing of said radial cuts after the tire has stopped. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
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34. A method for evaluating the quality of the composition blend forming a tread band in a pneumatic tire for vehicle wheels, said method comprising the steps of:
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a) forming a plurality of radial cuts in at least one portion of a radially external slick surface of said tread band, a first plurality of portions of said at least one portion lying between pairs of adjacent said cuts, said tread band comprising an internal band portion which directly underlies said at least one portion to be radially more internal relative to the at least one portion, said cuts of said at least one portion extending at most through a depth of said at least one portion, said internal band portion comprising a second plurality of portions which are not cut, wherein each portion of said second plurality of portions underlies a respective one of each of said first plurality of portions, the depth, width and mutual distance between said cuts being such that each portion of said first plurality of portions is immobile relative to the respective underlying portion of said second plurality of portions while the tire is being rotated; b) rotating the tire at a predetermined speed and with a predetermined load in contact with a friction surface, said cuts not performing any function as regards road holding of the tire; c) stopping the rotating of the tire; d) verifying wearing of said at least one tread band portion through observation of disappearing of said radial cuts after the tire has stopped.
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Specification