Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C3/00—Tyres characterised by the transverse section
  • B60C3/06—Tyres characterised by the transverse section asymmetric
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C15/00—Tyre beads, e.g. ply turn-up or overlap
  • B60C15/02—Seating or securing beads on rims
  • B60C15/0236—Asymmetric bead seats, e.g. different bead diameter or inclination angle
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/30—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers asymmetric to the midcircumferential plane of the tyre
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T152/00—Resilient tires and wheels
  • Y10T152/10—Tires, resilient
  • Y10T152/10495—Pneumatic tire or inner tube
  • Y10T152/10819—Characterized by the structure of the bead portion of the tire

Definitions

• the invention relates to a tire whose two beads are of different diameters and whose bead of larger diameter is intended to be disposed on the outside of a vehicle.
• This axial offset to the inside of the tire may have the consequence that, in the inflated and uncrushed state, it is the outer bead or the outer seat which are axially the outermost of the assembly. tire and wheel instead of the outer sidewall of the tire. This may result in greater sensitivity of the tire wheel or bead to various shocks and accidents in service.
• This axial offset also has the consequence of changing the visual appearance of the wheel tire assembly in a way that can have various consequences in terms of design and style of a vehicle.
• the invention relates to a tire having an apex with a median plane S, two sides, a first bead, of diameter O 1 intended to be disposed on the outside of a vehicle and a second bead, of diameter.
• O 2 intended to be arranged on the inside of a vehicle and such that ⁇ j > - ⁇ 2 , characterized in that when said tire is mounted on its service rim, inflated substantially to its nominal pressure and not crushed, the median plane S of the summit is axially offset towards the first bead relative to the median plane B of the beads of a distance D positive or zero.
• This tire is such that the influence of the axial offset due to inflation forces exerted on two sides of different lengths is canceled.
• the negative effects on endurance and damage in service for example during a climb or a descent of a sidewalk or during a sidewalk grating, are also canceled with respect to standard identical diameters.
• the invention also relates to a method of manufacturing a tire having an apex with a median plane S, two sidewalls, a first bead, of diameter O 1 , intended to be disposed on the outside of a vehicle and a second bead, of diameter O 2 , intended to be arranged on the inside of a vehicle and such that ⁇ j > ⁇ ⁇ 2 , characterized in that a mold is used in which, by calling plan median of the beads B the plane parallel to the plane S and disposed axially equidistant from the first and second beads, the median plane of the beads B is axially offset to the second bead relative to the median plane S of the vertex of a given distance L.
• the distance L is such that, when the tire is mounted on its service rim, inflated to its nominal pressure and not crushed, the median plane of the beads B is shifted axially towards the second bead relative to the median plane. S from the top of a distance D positive or zero.
• the distance L is such that L> - e is even
• the misalignment length between the two median planes L is greater than 4 mm and preferably greater than 5 mm.
• the baking mold is such that the second bead is substantially at the same axial distance from the median plane of the S top and the first bead is at a reduced axial distance of 2L from the median plane of the S-vertex.
• This modification of the baking mold is particularly easy to implement.
• the baking mold is such that the first and second beads are axially offset both by a distance L relative to the median plane of the summit S towards the small diameter bead.
• This modification of the baking mold requires intervention on the definition of the molding parts of the two beads and the two sides which is more expensive.
• FIG. 1 shows a partial meridian sectional view of a conventional tire mounted on its service rim and inflated to substantially its nominal pressure
• FIG. 2 shows, in a view similar to Figure 1, a second tire according to the invention
• - Figure 3 shows a partial meridian sectional view of the molding profile of a tire illustrating the invention.
• meridian or axial plane means any plane passing through the axis A of rotation of the wheel and the rim.
• Figure 1 is shown, seen meridian or partial axial section, a tire 1 mounted on its service rim 20, inflated to substantially its nominal service pressure and not crushed.
• the rim 20 forms with a disc 21 a monoblock wheel.
• the disc can also be manufactured independently of the rim and joined thereafter.
• the rim 20 comprises a first seat 22 and a second seat 24 intended to serve as a bearing surface for the first 3 and second 5 beads of the tire 1.
• the first seat 22 comprises a frustoconical bottom 221 locally confused with a cone of revolution coaxial with the rim and open in the direction of the second seat 24, a safety boss 222 extending the bottom 221 of the first seat 22 to the second seat 24, and an outer edge 223 extending the bottom 221 of the first seat on the opposite side to the second seat 24.
• the second seat 24 comprises a frustoconical bottom 241 locally confused with a cone of revolution coaxial with the rim and open towards the first seat 22, a safety boss 242 extending the bottom 241 of the second seat 24 to the first seat 22 and an outer edge 243 extending the bottom 241 of the second seat opposite the first seat 22.
• the maximum diameter of the second seat is less than that of the first seat.
• the order of magnitude of the difference between the maximum diameters is of the order of 20 mm.
• the gap between the minimum radii of the two seats is therefore of the order of 10 mm.
• the first circumferential groove 26 serves as a mounting groove for the first seat 22.
• the outside diameter of the bearing surface 28 substantially corresponds to the maximum diameter of the second seat 24 to allow a support (not shown) to be slipped onto this bearing surface 28 by passing through the second seat 24.
• the rim 20 shown is a preferred rim, but any other rim with unequal seat diameters applies to the tires according to the invention.
• the tire 1 comprises two beads 3 and 5 resting on the seats 22 and 24 of the rim 20, two sidewalls 7 and a top 9.
• Each bead comprises annular reinforcements oriented substantially circumferentially and substantially inextensible. These reinforcements, such as rods, are intended to ensure in service the maintenance of the beads on the rim seats.
• the first bead 3 has a diameter (minimum) ⁇ i greater than the diameter ⁇ 2 of the second bead 5.
• the median planes S median plane of the top and B, median plane of the beads mounted on their service rim (or median plane of the seats of the rim 20).
• the median plane S is defined as the plane perpendicular to the axis A and equidistant from the ends of the reinforcement plies 90 of the apex 9. It can be seen that the median plane S of the apex 9 is axially offset towards the second bead 5 by a distance D relative to the median plane B of the beads, the distance D is here negative taking as positive side of the axis A, the side directed outwardly of the rim 20.
• the resultant forces related to the inflation pressure in the axial direction is not substantially zero as usually for tires whose two beads have the same diameter, but is directed towards the side of the highest side, here the inner side of the rim.
• Figure 1 shows a tire 10 according to the invention mounted on its service rim 20, inflated to substantially its nominal pressure and not crushed.
• This tire comprises two beads 3 'and 5' resting on the seats 22 and 24 of the rim 20, two sidewalls 7 'and a top 9'.
• the median plane of the beads is marked B 'and the median plane of the summit S'. It can be seen that for this tire the plane S 'is axially offset towards the first bead 3' by a positive distance D '.
• the axially most externally located point of the tire assembly 10 and rim 20 is no longer the end of the bead 30 'but a portion of the side identified 71. This reinforces the strength of the tire 10 to the shocks and accidents that it is likely to encounter in service by reducing the exposure of the bead 3 '. This also has the advantage of positively modifying the visual appearance of the tire mounted on its service rim 20.
• Figure 3 is illustrated a preferred embodiment of the tire according to the invention.
• Figure 3 shows the profile of the tires 1 and 10 during their molding in their baking mold (not shown).
• the tire 1 has a molding profile such that the median planes of the beads and the apex coincide substantially during its baking.
• the two beads 3 and 5 are shown bearing on rim seats 22 and 24, but the distance between the two seats may be identical to the distance of the seats of the service rim 20 or higher or lower. What is important is that the two median planes B and S for the tire 1 are substantially merged.
• the tire 10 has a molding profile similar to that of the tire 1 with the exception of the position of the bead 3 'which is shifted axially inward by a distance 2L.
• This distance 2L is, in the case of a difference in diameters of the beads of the order of 20 mm greater than 8 mm and preferably 10 mm.
• Figure 3 (like the other figures) is not scaled to illustrate displacements.
• the median plane of the crown S 'of the tire 10 remains well confused during firing with the median plane of the crown S of the tire 1.
• the median plane of the beads B' is offset axially. from a distance L to the bead 5 of smaller diameter.
• This embodiment is easy to implement and reduces the necessary costs because it is necessary to substantially modify the shells that keep the bead moved without intervening on the rest of the mold.
• Tests were carried out with a tire of size 235-660 R480 U, having a gap diameter of beads of 20 mm.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)
• Moulds For Moulding Plastics Or The Like (AREA)
• Heating, Cooling, Or Curing Plastics Or The Like In General (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=37075149

Family Applications (1)

Country Status (4)

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Family Cites Families (16)

• 2007
  • 2007-01-30 JP JP2008552796A patent/JP5148511B2/ja not_active Expired - Fee Related
  • 2007-01-30 EP EP07712137A patent/EP1981722A1/de not_active Withdrawn
  • 2007-01-30 US US12/162,380 patent/US8109309B2/en not_active Expired - Fee Related
  • 2007-01-30 WO PCT/EP2007/050917 patent/WO2007088169A1/fr active Application Filing

Non-Patent Citations (1)

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