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
  • B60C17/00—Tyres characterised by means enabling restricted operation in damaged or deflated condition; Accessories therefor
  • B60C17/01—Tyres characterised by means enabling restricted operation in damaged or deflated condition; Accessories therefor utilising additional inflatable supports which become load-supporting in emergency
  • B60C17/02—Tyres characterised by means enabling restricted operation in damaged or deflated condition; Accessories therefor utilising additional inflatable supports which become load-supporting in emergency inflated or expanded in emergency only
• • 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
• • 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
  • Y10T152/10522—Multiple chamber
  • Y10T152/10576—Annular chambers
  • Y10T152/10594—Mutually free walls

Definitions

• the invention relates to a means for supporting the tread of a tire.
• Said support means constitutes with said tire and its mounting rim a rolling assembly for a vehicle, intended to be able to roll after a consequent and unexpected loss of pressure of the tire, said tire being more particularly a tire without chamber of the Truck or Engineering type. Civil.
• French application FR 2 756221 describes and claims, as a tread support or support means, a reinforced rubber toric membrane, inflated to a pressure P Q greater than the pressure p, of the tire cavity, and having, in the inflated state, a radius of apex R ", less than the crushed radius Rc of the tire used at its recommended pressure, said membrane being at least at its apex reinforced by at least one ply of wires or cables, said apex of said membrane further comprising at least one hooping reinforcement of circumferentially oriented wires or cables and having a breaking force per cm of ply at least equal to the product of the apex radius R by pressure, per cm of surface of said ply, leading at a tension per cm of ply equivalent to the tension due to the maximum centrifugal force to which the tire can be subjected and allowing the breaking of the hooping wires or cables for a pressure differential PO - P ⁇ , existing in the event of a loss of pressure undergone by the tire
• the internal pressure p of said membrane measured when cold, that is to say at 20 ° C., is greater than the pressure p of the internal cavity of the tire by
• the apex radius R of the toric membrane is preferably between 0.80 and 0.97 times the crushed radius P ⁇ , of the tire, mainly for reasons of heating of said tire, a too high pressure difference risks d 'Altering a certain number of properties of the tire itself, for example the endurance of the carcass reinforcement of said tire, while requiring too large a hooping reinforcement.
• the top of said membrane is preferably reinforced by two plies of wires or cables parallel to each other in each ply and crossed from one ply to the next, making an angle between 50 ° and 85 ° with the circumferential direction.
• the cables or wires are advantageously textile for reasons of lightness, flexibility and good resistance to corrosion, and preferably made of aromatic polyamide.
• the axial ends of the two plies are preferably located on the sides of the membrane, so that, if S is called the maximum axial width of the carcass reinforcement of the tire, the width of the plies is preferably between S and 1 , 30 S.
• the pressure difference p 0 - P J increases in the event of a puncture in the tire and the cables of the hooping ply (s) break, the toric support membrane expands in the cavity of the tire and allows rolling of the assembly. despite the pressure drop in the tire cavity.
• the toric membrane in accordance with the invention described in the above-mentioned French application, can optionally include sidewalls each reinforced by at least one ply of radial wires or cables, said sidewalls being able to be advantageously provided with radial grooves opening onto the metal rim mounting the tire.
• the membrane Under the normal running conditions of the assembly formed by the tire, its mounting rim and the membrane, load, pressure and speed conditions recommended for the tire concerned, the membrane retains an equatorial radius that is practically constant and less than the crushed radius of the tire, and the outer walls of its sidewalls are for the most part in permanent contact with the inner walls of the tire.
• the friction existing between said walls causes premature degradation and wear of the impermeable rubber layer which covers the inner wall of the tire.
• the rupture of the winding rods causes, in the case of a so-called closed support membrane (the cross section of said membrane has a continuous contour), a strong extension of the membrane portions located radially below said rods, where rupture of said portions and leakage of inflation gas from said membrane.
• the sidewall reinforcement ply is anchored in each lower flank portion by winding around an inextensible annular reinforcement element, not breaking under the effect of the tension induced by the action of the flank ply and the inner diameter D is between the value D R and a value equal to D s minus the product of the width L s of the rim seat by the tangent of the angle of inclination of said seat,
• said side reinforcement ply consisting of reinforcing elements, each element being composed of a core having a breaking force on the one hand greater than the tension, per ply element, due to the pressure differential p 0 - p 1 and at the maximum centrifugal force undergone by said element, and on the other hand such that it allows the rupture of said flank ply elements for a pressure differential p 0 - p'j greater than p 0 - p, and after the rupture of the elements of the hoop ply ,
• said core being surrounded by a wire or cable wound helically,
• said sidewall reinforcement element having a curve, representing the tension as a function of the relative elongation ⁇ , having, for an elongation greater than the elongation at break ⁇ A of the core, a segment where the variation the tensile force as a function of the elongation is substantially zero,
• the elongation at break ⁇ R of the reinforcing element being at least equal to the ratio of the difference between the interior meridian length of the tire and the exterior meridian length of the membrane over the exterior meridian length of the membrane.
• the internal diameter D of the inextensible reinforcing annular element is between the value D s and the value equal to D s minus the product of the width L s of the rim seat by the tangent of the angle d tilting of said seat.
• the top of the membrane is said to be reinforced by a ply when the presence of said ply at the top is effective, whatever the actual width of the ply.
• a membrane flank is said to be reinforced by a ply if there is indeed a ply in the flank; thus a ply anchored to the two membrane rods is a flank reinforcement ply but also a crown reinforcement ply.
• FIG. 1 schematically represents a toroidal support membrane in accordance with the invention
• FIG. 2 schematically represents the membrane of FIG. 1 in position in the tire mounted on its service rim and inflated
• FIG. 3 schematically represents a reinforcing element used for the sidewall reinforcing ply of the membrane
• FIG. 4 represents the curve giving the tension force as a function of the relative elongation of a reinforcement element of the side reinforcement ply
• the toric membrane M is, in the first example described, ( Figure 1), closed and reinforced at its top (1). Of small and constant thickness on its radially inner part (10), it is thicker on its sides (11) and at the top (1). It is generally reinforced by two plies (120), each ply consisting of reinforcing elements, parallel to each other in the ply, and making an angle of between 50 ° and 85 ° with the equatorial line XX 'of the assembly, more precisely equal to 60 °, an angle which will be one direction for one of the plies and opposite direction for the other ply.
• each of the two plies (120) is such that one of its ends A is located in the region of one of the shoulders of the membrane M, while the other end B of said ply (120) is the end of the upturn (20) which it forms after winding around an annular reinforcing element (2) in the lower part of the membrane flank situated on the side opposite to said shoulder.
• the two plies (120) therefore ensure, in the region AA of the top of the membrane M the function of two top reinforcement plies of elements parallel to each other in each portion of the ply and crossed from one ply to the next by making with the equatorial direction an angle of 60 °, and in the region AB of the flanks the function of flank reinforcement ply, each flank being reinforced by a ply of elements making with the equatorial direction a variable angle less than 90 ° and greater at the angle measured in the equatorial plane.
• the assembly (12) of the two crown plies (120) thus formed, easily expandable, can be surmounted by a rubbery support strip (14) provided with frustoconical relief elements (140) separated from each other by recesses ( 141).
• frustoconical "studs” form on the surface of the strip (14) circumferential rows, so that, between two rows of studs (140) axially adjacent, is arranged a hooping strip (131) of circumferential cables, formed of three aromatic polyamide yarn.
• Each annular reinforcement element (2) is formed by winding aromatic polyamide 167x2 cables. Such a composition gives said annular element almost perfect extensibility and a breaking strength at least equal to 1.05 times the necessary resistance induced by the tension exerted on the annular element of the reinforcing elements of the sidewall ply: thus the 'annular element (2) can be in the conditions mentioned qualified as inexhaustible and unbreakable.
• Said annular element is disposed radially as close as possible to the tire mounting rim, and, in the case shown, its internal diameter is between the nominal diameter of the rim D s and the value D s minus the product L s . tg ⁇ , L s being the axial width of the tire bead seat and tg ⁇ the tangent of the angle of inclination of the seat of the mounting rim.
• Each reinforcement element (15) of the sidewall and crown reinforcement ply (120) consists of a core (150), itself formed of a 122x1 rayon reinforcement element.
• Said core has (FIG. 4) a breaking force F RA equal to 6.2 daN for a relative elongation ⁇ A of 7.5% (point M of the curve representing the force as a function of the relative elongation).
• F RA breaking force
• Around said core are wound wires (151) of 167 tex, each wire (151) being twisted on itself and the two wires (151) being twisted around the core (150).
• the reinforcing element (15) thus obtained, and said to have a brittle core, has an elongation at break ⁇ R equal to 90% (point R of the curve), which is much greater than the elongation ⁇ A at break of the core (150): after rupture of said core, the element reinforcement (15) therefore has a high potential for elongation before its own rupture NR portion of the curve), potential estimated at more than 80%. Said potential is very largely sufficient to allow complete expansion of the membrane until filling the pneumatic cavity, since the necessary and sufficient elongation is equal to the ratio of the difference between the inner meridian length of the tire and the outer meridian length of the membrane along the outer meridian length of the membrane, said lengths being measured from rod to rod.
• each hooping element will consist of a core of aromatic polyamide 110 ⁇ 1, and wrapped around said core of two cables of aromatic polyamide 167 ⁇ 2.
• the core of the hooping element then breaks for the supported tension which results from the lowering of the pressure pi, while the overall element is not broken although it has become very extensible.
• the solution makes it possible to avoid as much as possible the dispersion of the pieces of strip after breakage of the latter, at the cost, however, of a significantly higher material cost.
• the assembly E is composed of the tire P, of dimension 495/45-R-22.5 in the example described, of the mounting rim J, and of the toric membrane M according to the invention.
• Tire P is a tire universally known, with sides joined radially outside to a tread (21) and extended radially inside to two beads (22), each bead (22) being reinforced by at least one rod (23) around from which is anchored a radial carcass reinforcement (24) to form reversals (25).
• Said carcass reinforcement (24) is surmounted radially in the crown by a crown reinforcement (26), composed of at least two plies of wires or metallic cables parallel to each other in each ply and crossed from one ply to the next in making an angle with the circumferential direction which can be between 5 ° and 45 °.
• the tire P is said to be tubeless, and internally comprises a layer of rubber mixture impermeable to the inflation gases.
• FIG. 5 shows the simplest support membrane architecture, the top and the sides of said membrane being seen on plan.
• the sides (11) are reinforced by a single radial ply (120) of reinforcing elements (15) with brittle core of the same constitution as those described above but radial.
• Said radial ply is also a crown ply since it continues axially from rod (2) to rod (2) of membrane M.
• the summit (1) of said membrane is additionally reinforced by a hoop ply (13) disposed radially below the support strip (14), said hoop ply being formed of reinforcing elements so that the breaking force per cm of ply is a linear function of the inflation pressure pi of the tire cavity, the angular coefficient of the representative straight line being equal to 0.05 and the ordinate at the origin of said straight line being equal to 0.3.10 Pa, the tire concerned being a "Truck" tire.
• the top is advantageously completed, radially outside the hooping ply, by at least one ply of metallic reinforcing elements corrugated in the plane of the ply, parallel to each other in the sheet and oriented with respect to the circumferential direction with an angle which may be between 0 ° and 90 °, the amplitude and wavelength of the undulations being obviously chosen so as not to hinder the radial expansion of the membrane.
• FIG. 6 a membrane architecture with two continuous plies (120) of rod (2) to rod (2), formed of reinforcement elements (15) with brittle core of the same constitution as those described above, but crossed from one layer to the next, making an angle with the circumferential direction, measured in the equatorial plane of the membrane, between 50 ° and 85 °, and more precisely equal to 60 °.
• the two plies (120) are side reinforcement plies and crown reinforcement plies, the summit being complemented by a hooping ply (13) such as that shown in FIG. 5 and described above.
• the architecture shown in FIG. 7, includes a sidewall and top reinforcement ply (120), since it continues from rod (2) to rod (2), said ply (120) being formed from the same elements with brittle core as previously. , said elements being parallel to each other in the sheet and forming with the circumferential direction an angle of 60 ° (but may be between 50 ° and 85 °), measured at the top of the membrane.
• the ply (120) is in the crown radially surmounted by a crown ply (121) of defined axial width and composed of the same reinforcing elements as those of the ply (120), but crossed with the latter while making with the direction circumferential the same angle, but of opposite direction.
• the ply (121) can be radially surmounted by the support strip (14) provided with frustoconical relief elements (140) separated from each other by the recesses (141). These "studs" frustoconical form on the surface of the strip (14) circumferential rows, so that, between two rows of studs (140) axially adjacent, is arranged a hooping strip (131) of circumferential cables, the whole of which forms the ply hooping (13).
• the ply (121) can also be surmounted more simply by a hooping ply such as that shown in FIG. 5 and described in the passage corresponding to said figure.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)
• Separation Using Semi-Permeable Membranes (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

ID=9533048

Family Applications (1)

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Citations (3)

Family Cites Families (3)

• 1998
  • 1998-11-20 FR FR9814695A patent/FR2786131A1/fr active Pending
• 1999
  • 1999-11-16 CA CA002351670A patent/CA2351670C/fr not_active Expired - Fee Related
  • 1999-11-16 EP EP99972585A patent/EP1140528B1/fr not_active Expired - Lifetime
  • 1999-11-16 JP JP2000583728A patent/JP4691256B2/ja not_active Expired - Fee Related
  • 1999-11-16 WO PCT/EP1999/008792 patent/WO2000030877A1/fr not_active Ceased
  • 1999-11-16 BR BR9915432-3A patent/BR9915432A/pt not_active IP Right Cessation
  • 1999-11-16 DE DE69940356T patent/DE69940356D1/de not_active Expired - Lifetime
  • 1999-11-16 AU AU13833/00A patent/AU756168B2/en not_active Ceased
  • 1999-11-16 AT AT99972585T patent/ATE421435T1/de not_active IP Right Cessation
• 2001
  • 2001-05-18 US US09/861,358 patent/US6481481B2/en not_active Expired - Fee Related

Patent Citations (3)

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