US-12623493-B2 - Tire tread for a tire and tire and curing mould to manufacture a tire tread

US12623493B2US 12623493 B2US12623493 B2US 12623493B2US-12623493-B2

Abstract

A tire tread ( 100 ) for a tire ( 101 ) comprising, a top side ( 10 ) configured to engage a ground surface during tire operation, a bottom side ( 20 ) configured for attachment to a tire carcass ( 105 ), a tread thickness ( 40 ) extending from the bottom side ( 20 ) to the top side ( 10 ) along a radial direction (R), a first lateral side ( 50 ) connecting the top side ( 10 ) with the bottom side ( 20 ), a second lateral side ( 60 ) connecting the top side ( 10 ) with the bottom side ( 20 ), wherein the first lateral side ( 50 ) is spaced apart from the second lateral side ( 60 ) along an axial direction (A). The tire tread ( 100 ) further comprises a plurality of grooves ( 70 ) extending into the tread thickness ( 40 ) from the top side ( 10 ) and terminating within a first depth ( 71 ) of the tire tread ( 100 ) at a groove bottom ( 75 ). Furthermore, the tire tread ( 100 ) a first shoulder track ( 51 ) limited by the top side ( 10 ), the bottom side ( 20 ) and the first lateral side ( 50 ), a second shoulder track ( 61 ) limited by the top side ( 10 ), the bottom side ( 20 ) and the second lateral side ( 60 ), wherein the first shoulder track ( 51 ) and/or the second shoulder track ( 61 ) comprise a preset geometry for an improved pressure distribution, wherein the first shoulder track ( 51 ) comprises a first shoulder track width ( 55 ) and a first reduced tread thickness ( 41 ) with respect to the tread thickness ( 40 ) and/or wherein the second shoulder track ( 61 ) comprises a second shoulder track width ( 65 ) and a second reduced tread thickness ( 42 ) with respect to the tread thickness ( 40 ).

Inventors

Mario Korbas
Ronald Daries
Jens Kleffmann

Assignees

CONTINENTAL REIFEN DEUTSCHLAND GMBH

Dates

Publication Date: 20260512
Application Date: 20241010

Claims (4)

1 . A precured tread for a retread tire comprising: a top side configured to engage a ground surface during tire operation, a flat bottom side configured to bond to a flat bonding surface of a tire casing with a cushion gum, a tread thickness extending from the bottom side to the top side, a first lateral side connecting the top side with the bottom side, a second lateral side connecting the top side with the bottom side, wherein the first lateral side is spaced apart from the second lateral side along an axial direction, a plurality of grooves extending into the tread thickness from the top side and terminating within a first depth of the tire tread at a groove bottom, a first shoulder track limited by the top side, the bottom side and the first lateral side, a second shoulder track limited by the top side, the bottom side and the second lateral side, wherein the first shoulder track and the second shoulder track comprise a preset geometry for an improved pressure distribution when the precured tread is bonded to the tire casing and forms the retread tire, wherein, in an unbonded state when viewed in axial cross-section, the first shoulder track comprises a first shoulder track width and a first laterally outward portion with a reduced tread thickness with respect to the tread thickness in which this first laterally outward portion with reduced tread thickness is defined by the first lateral side, and wherein the second shoulder track comprises a second shoulder track width and a second laterally outward portion with a reduced tread thickness with respect to the tread thickness in which this second laterally outward portion with reduced tread thickness is defined by the second lateral side, and wherein, in the unbonded state when viewed in axial cross-section, each of the first and second lateral sides has a lower inwardly sloped surface extending from the flat bottom side to an intermediate area between the top and bottom sides, and has a upper inwardly sloped surface extending from the intermediate area to the top side, the upper sloped surface having a greater inward slope than the lower sloped surface such that each of the first and second lateral sides has a convex profile in axial cross-section.
2 . A retread tire comprising: a tire casing having a flat bonding surface when viewed in axial cross-section, the precured tread according to claim 1 , and a bonding layer arranged between the tire casing and the precured tread, wherein the bonding layer includes a cushion gum that bonds the flat bonding surface of the tire casing to the flat bottom side of the precured tread.
3 . The precured tread according to claim 1 , wherein each lower inwardly sloped surface of the first and second lateral sides is a planar surface defined by a lower chamfer of each first and second lateral side, and wherein each upper inwardly sloped surface of the first and second lateral sides is a planar surface defined by an upper chamfer of each first and second lateral side, wherein the intermediate area of each first and second lateral side is an intermediate junction edge defined by respective portions of the planar surfaces of the upper and lower chamfers of the first and second lateral sides, wherein the planar surface of the upper sloped surface of the first lateral side defines a first area as measured from the intermediate junction edge to the top side, in which this first area extends from 25% to 75% of the first shoulder track width, and wherein the planar surface of the upper sloped surface of the second lateral side connects to the top side at a second area, which extends from 25% to 75% of the second shoulder track width.
4 . The precured tread according to claim 3 , wherein the planar surface of the upper sloped surface of the first lateral side extends from 55% to 85% of the tread thickness and wherein the planar surface of the upper sloped surface of the second lateral side extends from 55% to 85% of the tread thickness.

Description

The disclosure relates to a tire tread for a tire. The disclosure further relates to a tire for a vehicle and a curing mould to manufacture a tire tread. A tire for a vehicle, which can also be referred to as “vehicle tire”, “motor vehicle tire” or “pneumatic tire”, has a tread. This is an outer, circumferential surface with which the tire can roll on a surface. The tire can be mounted on a rim. It is desirable to provide a tire that can be reliably and efficiently built. It is further desirable to provide a tire tread with improved performance. It is further desirable to provide a curing mould to manufacture a tire tread for a tire. Embodiments of the disclosure relate to a tire tread for a tire. The tire comprises a tire casing. The tire comprises the tire tread. The tire tread comprises a running surface. In particular, the tire tread is configured to roll on a surface during operation. Embodiments of the disclosure further relate to a curing mould for manufacturing the tire tread. In particular, the tread is a so-called precured tread for a cold retreading process. The tire carcass, for example, is the tire casing of a worn tire which is buffed such that an old tread is removed. The new tread is the precured tread which is provided separately during manufacturing of the tire and is fixed to the tire carcass by a bonding layer comprising a cushion gum. The precured tread is produced in a mould with a specific geometry depending on the application and performance requirements. The tire tread extends in a mounted state in the direction of rotation of the vehicle tire. Retreading, which is also known as remoulding, is the process of recycling a tire that is worn, but still has enough of a solid structure so that the treads can be replaced. There are two main retreading processes: mould cure retreading, which can also be referred to as hot retreading. And precure retreading, which can also be referred to as cold retreading. Retreading tires is economical and environmentally friendly. When using the mould cured or remould process, raw i.e., unvulcanised, rubber is wrapped around the tire in one continuous strip similar to manufacturing of a new tire. Then, the tire is placed in a rigid mould to be cured. Precure retreading works by wrapping a new tread with the new tread design around the old tire casing and splicing it using a bonding agent with a cushion gum. The new tread has already been vulcanized, i.e., sulphur treated, and heat treated. The tire is then placed into a chamber to be cured. Precured treads are produced in flat moulds and due to that, the final product has parallel top and bottom surfaces. During the retreading process, the worn tire is buffed to a specific contour and the cushion gum is applied. The contour and the cushion gum determine the contour of the final tire after application of the precured treads. The tire tread comprises a top side configured to engage a ground surface during tire operation. The tire tread comprises a bottom side configured for attachment to a tire carcass. A tread thickness is extending from the bottom side to the top side along a radial direction. The tread thickness is limited in its extension by the top side and the bottom side. The tire tread comprises a first lateral side connecting the top side with the bottom side and a second lateral side connecting the top side with the bottom side. The first lateral side is spaced apart from the second lateral side along an axial direction. The first lateral side and the second lateral side are two opposing lateral sides. The top side and the first lateral side intersect at a first point when the cross-section of the tire tread is viewed in the direction of rotation. Considering the whole tire tread, the first intersection point has the extension of a first intersection edge. The first intersection edge extends along the direction of rotation. The first intersection edge is, for example, angular or rounded with a defined radius of curvature. The top side and the second lateral side intersect at a second point when the cross-section of the tire tread is viewed in the direction of rotation. Considering the whole tire tread, the second intersection point has the extension of a second intersection edge. The second intersection edge extends along the direction of rotation. The second intersection edge is, for example, angular or rounded with a defined radius of curvature. The tread thickness is the thickness of the tread, which has the highest value across the tire tread. The highest value of the thickness is, for example, at the centre of the tire tread. The centre of the tire tread is a region between the first lateral side and the second lateral side. The centre of the tire tread is, for example, equidistant from the first lateral side and from the second lateral side. The tread thickness is measured in an area of the tread where no groove is located. The tire tread further comprises a plurality of grooves extending in