Method of treading tires
AssigneeKentredder Limited
InventorsPeter Jan Kent, John Eric Phillips, Jan Herbert Farquharson Kent
Life of this patent
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Abstract
A method of treading or re-treading tires involves compression of the wearing surface of the tread. A tread strip, which may be an annular band, is compressed in a direction parallel to its longitudinal axis and is bonded to a tire carcass, while being maintained under compression. This may be done by compressing a tread band into an undersized mould; apparatus for assisting this is also described. Alternatively, the tread strip may be of finite length, for example to form a lug, in which case the strip is formed with a radius of curvature less that of the surface to which it is to be applied, so that the convex (wearing) surface of the strip is compressed upon application to the carcass.
Claims22
A method of applying a tread to a tire carcass comprising the steps of providing a prevulcanized tread in strip form, placing the tread on the carcass with at least the wearing surface of the tread in a direction parallel to the longitudinal axis of the strip being shortened with there being a compressive stress in the tread longitudinally axially of the strip, and then bonding the compressed tread to the relatively uncompressed carcass while maintaining the compressive stress in the tread with the compressive stress remaining in the tread after it is bonded to the carcass so that the wearing surface of the final assembly remains under compressive stress.
A method of applying a tread to a tire carcass comprising the steps of providing a prevulcanized tread including an outer wearing surface, and an inner concave surface, said prevulcanized tread being in the form of a curved strip having a radius of curvature less than the like radius of curvature of the carcass surface to which the prevulcanized tread is to be applied, reshaping the curvature of the prevulcanized tread to increase the radius of curvature of said inner surface and thereby shortening the outer wearing surface in the direction of curvature with there being a compressive stress introduced in the outer wearing surface and then bonding the inner concave surface of the reshaped prevulcanized tread to the carcass while maintaining the compressive stress in the outer wearing surface with the compressive stress remaining in the tread after it is bonded to the carcass so that the wearing surface of the final assembly remains under compressive stress.
Dependencies are inferred from the claim text.