CONNECTING MEMBER FOR AN AIR MAINTENANCE TIRE AND METHOD OF FORMING THE SAME

Abstract

A connecting member and method of forming the connecting member in an air maintenance tire is provided. The method includes providing a tire having a sidewall formed with an annular groove. The groove receives an annular air tube having a first end with a first fitting and a second end with a second fitting. A recess is formed in the tire sidewall along the annular groove at a location where the first end of the annular air tube is adjacent the second end of the annular air tube. A mold formed with a cavity is provided and the fittings are removably secured in the cavity. The mold is positioned on a surface of the tire sidewall and an elastomer or a polymer is introduced into the mold cavity. The mold is heated to form the connecting member on the tire sidewall.

Claims

1. A method of forming a connecting member in an air maintenance tire, the method comprising the steps of: providing a tire that includes a sidewall, the sidewall being formed with an annular groove which receives an annular air tube, the annular air tube including a first end receiving a first fitting and a second end receiving a second fitting; forming a recess in the tire sidewall along the annular groove at a location where the first end of the annular air tube is adjacent the second end of the annular air tube; providing a mold being formed with a cavity; removably securing the first fitting in the cavity and removably securing the second fitting in the cavity; positioning the mold on a surface of the tire sidewall; introducing at least one of an elastomer and a polymer into the mold cavity; and heating the mold, whereby the connecting member is formed on the tire sidewall.

2. The method of forming a connecting member of claim 1, wherein the mold is formed with openings extending from the cavity to an exterior surface of the mold, and the first fitting is removably secured in a selected one of the openings and the second fitting is removably secured in another selected one of the openings.

3. The method of forming a connecting member of claim 1, further comprising the step of introducing adhesive material into the recess.

4. The method of forming a connecting member of claim 3, wherein the adhesive includes at least one of a solid adhesive and a flowable adhesive.

5. The method of forming a connecting member of claim 1, further comprising the step of forming an undercut in the tire sidewall about at least one of the radially inward periphery of the recess and the radially outward periphery of the recess.

6. The method of forming a connecting member of claim 1, further comprising the step of forming a first relief area in the tire sidewall adjoining the recess along the annular groove.

7. The method of forming a connecting member of claim 6, further comprising the step of forming a second relief area in the tire sidewall adjoining the recess along the annular groove.

8. The method of forming a connecting member of claim 7, wherein when the mold is positioned on the surface of the tire sidewall the first and second fittings seat in the recess, the first end of the annular tube seats in the first relief area and the second end of the annular tube seats in the second relief area.

9. The method of forming a connecting member of claim 1, wherein the at least one of an elastomer and a polymer is in a solid form.

10. The method of forming a connecting member of claim 1, wherein the at least one of an elastomer and a polymer is in a flowable form.

11. The method of forming a connecting member of claim 1, further comprising the step of removably securing the mold against the sidewall of the tire by mechanical means.

12. The method of forming a connecting member of claim 1, further comprising the step of placing a platen into contact with the mold.

13. A connecting member formed according to the steps of the method of claim 1.

14. A tire including a connecting member formed according to the steps of the method of claim 1.

15. A vehicle including a tire that in turn includes a connecting member formed according to the steps of the method of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The invention will be described by way of example and with reference to the accompanying drawings, in which:

[0011] FIG. 1 is a fragmentary elevational view of an outboard side of a tire including components of a valve stem-based air maintenance tire system;

[0012] FIG. 2 is a fragmentary perspective view of an outboard side of a tire showing a recess formed in the tire sidewall, as included in an exemplary embodiment of the connecting member for an air maintenance tire and method of forming the same of the present invention;

[0013] FIG. 3 is a fragmentary perspective view of an adhesive patch disposed in the recess shown in FIG. 2;

[0014] FIG. 4 is a fragmentary perspective view of a flowable adhesive disposed in the recess shown in FIG. 2;

[0015] FIG. 5 is a fragmentary perspective view of the interior surface of a mold to which nozzles are removably secured, as included in an exemplary embodiment of the connecting member for an air maintenance tire and method of forming the same of the present invention;

[0016] FIG. 6 is a perspective view of the exterior surface of the mold shown in FIG. 5;

[0017] FIG. 7 is a fragmentary perspective view of the mold shown in FIG. 6 as disposed on the tire shown in FIG. 2; and

[0018] FIG. 8 is a fragmentary perspective view of a connecting member of the present invention as formed on the tire shown in FIG. 2.

[0019] Similar numerals refer to similar parts throughout the drawings.

DETAILED DESCRIPTION OF THE INVENTION

[0020] It is to be understood that the term inboard or inboardly is referred to herein as a direction corresponding to the axially inner surface or side of a tire, and the term outboard or outboardly is referred to herein as a direction corresponding to the axially outer surface or side of a tire. The term axially inwardly refers to an axial direction that is toward the center plane of a tire, and the term axially outwardly refers to an axial direction that is away from the center plane of a tire. The term radially inwardly refers to a radial direction that is toward the central axis of rotation of a tire, and the term radially outwardly refers to a radial direction that is away from the central axis of rotation of a tire.

[0021] Turning to FIG. 1, a tire 12 is mounted on a rim 14 in a conventional manner as known to those skilled in the art and defines a cavity (not shown). An exemplary air maintenance tire system, such as a valve stem-based air maintenance tire system, is indicated at 16. The air maintenance tire system 16 includes a peristaltic pump assembly 18. The peristaltic pump assembly 18 includes an annular air tube 20 that is received in an annular groove 38 formed in a sidewall 34 of the tire 12 and/or rim 14, and in turn encloses an annular passageway (not shown).

[0022] A first connecting tube 22 attaches to a first end 24 of the annular air tube 20 and fluidly connects the first end of the annular air tube to a valve housing 26 of the pump assembly 18. A second connecting tube 28 attaches to a second end 30 of the annular air tube 20 and fluidly connects the second end of the annular air tube to the valve housing 26.

[0023] When the tire 12 rotates under load along a ground surface, the annular air tube 20 is sequentially flattened or squeezed at the tire footprint. The sequential flattening of the annular air tube 20 and its passageway, segment by segment, directs air to the valve housing 26. A tire valve stem (not shown), including a check valve, is fluidly connected to the valve housing 26 and is in fluid communication with the tire cavity. When the air pressure is sufficient against the check valve and the air pressure within the tire cavity is below a set pressure level, air passes into the tire cavity. When the air pressure level within the tire cavity is at or above the set pressure, the check valve closes and air from the pump assembly 18 is vented by a relief valve in the valve housing 26 to atmosphere.

[0024] As seen in FIG. 1, the valve housing 26 of the pump assembly 18 is disposed within the rim 14. The connecting tubes 22, 28 pass through an opening 36 formed in the rim 14 and extend to a fairly rigid elastomer or polymer mounting member 32, which is referred to as a dome. The dome 32 is secured to the sidewall 34 of the tire 12, and facilitates the fluid connection of the first connecting tube 22 to the first end 24 of the annular air tube 20 through a first fitting 40 and the fluid connection of the second connecting tube 28 to the second end 30 of the annular air tube through a second fitting 42. In the prior art, the dome 32 has been pre-formed and then separately attached to the tire sidewall 34, which is inefficient and may not provide optimum reliability.

[0025] The connecting member and method of forming the connecting member in an air maintenance tire of the present invention is referred to generally at 50 and is shown in FIGS. 2 through 8. An exemplary connecting member 52, also referred to as a dome, formed by the method 50 of the present invention is shown in FIG. 8. For the purpose of convenience, the numbering of components in FIGS. 2 through 8, with the exception of dome 52, will remain consistent with the numbering of components in FIG. 1.

[0026] Turning now to FIG. 2, the connecting member and method of forming the connecting member in an air maintenance tire 50 includes forming a recess 54 in the tire sidewall 34 at a predetermined point along the annular groove 38. More particularly, the recess 54 is formed at the location where the first end 24 of the annular air tube 20 is adjacent the second end 30 of the annular air tube. The first fitting 40 and the second fitting 42 each are received in the recess 54. The recess 54 is of a sufficient depth to receive the fittings 40 and 42, while not intruding upon the tire cavity. The recess 54 preferably is formed in the tire 12 after the tire has been cured or vulcanized.

[0027] An undercut 56 preferably is formed about the radially inward periphery 58 of the recess 54 and the radially outward periphery 60 of the recess. The undercut 56 enables mechanical engagement of the dome 52 (FIG. 8) with the tire sidewall 34, as will be described in greater detail below. A first relief area 62 preferably is formed adjoining the recess 54 along the annular groove 38 about the first end 24 of the annular tube 20, and a second relief area 64 preferably is formed adjoining the recess along the annular groove about the second end 30 of the annular tube. Each relief area 62 and 64 enables easy temporary elevation of the fittings 40 and 42 away from the annular groove 38 for the formation of the dome 52, as will be described in greater detail below.

[0028] Referring to FIGS. 3 and 4, the fittings 40 and 42 (FIG. 2) are temporarily moved out of the recess 54. Adhesive material such as a solid adhesive 66, including an adhesive or rubber patch 66 (FIG. 3), and/or a flowable adhesive 68 (FIG. 4), including rubber cement, glue, epoxy and the like, is introduced into the recess 54. Preferably the flowable adhesive 68 is also introduced into the first relief area 62 and the second relief area 64.

[0029] As shown in FIG. 5, when the fittings 40 and 42 are moved out of the recess 54, they are removably secured to a mold 70. More particularly, the mold 70 includes a mold body 72 that includes an interior surface 76 formed with a cavity 74. The cavity 74 is sized to cover the recess 54 and the relief areas 62, 64 (FIG. 2). Each one of a pair of openings 78 and 80 are formed in the mold body 72 and extend from the cavity 74 to an exterior surface 82 (FIG. 6) of the mold body. The first fitting 40 is inserted into a respective one of the openings 78 and the second fitting 42 is inserted into the other respective one of the openings 80. The fittings 40 and 42 are preferably formed of a rigid material, such as brass, copper, steel or other metal, or of a rigid, high-melting point plastic or composite. By being formed of such materials, the fittings 40 and 42 are robust and firmly engage the openings 78 and 80 during curing of the dome 52, as will be described in greater detail below. It is to be understood that the fittings 40 and 42 may be of various constructions and may include supporting features, such as hose-supporting springs 84.

[0030] The openings 78 and 80 formed in the mold body 72 thus secure the relative position of each fitting 40 and 42 in the mold cavity 74, and prevent material from flowing into a pneumatic opening 86 (FIG. 8) of each respective fitting. Such prevention of material flow into each pneumatic opening 86 preserves fluid communication between the connecting tubes 22, 28 (FIG. 1) and the annular tube 20. Once the fittings 40 and 42 are inserted into respective openings 78 and 80, a selected elastomer or polymer is introduced into the mold cavity 74. The elastomer or polymer may be in a solid form, such as pellets, strips or particulate matter, and packed into the mold cavity 74 before the mold body 72 is placed into contact with the tire 12. Alternatively, the elastomer or polymer may be in a molten or flowable form, and may thus be flowed into the mold cavity after the mold body 72 is placed into contact with the tire 12.

[0031] Turning now to FIGS. 6 and 7, the mold body 72 is positioned on the surface of the tire sidewall 34. When the mold body 72 is positioned on the tire sidewall 34, the fittings 40 and 42 are seated in the recess 54 (FIG. 2), the first end 24 of the annular tube 20 is seated in the first relief area 62 and the second end 30 of the annular tube is seated in the second relief area 64. The mold body 72 preferably is secured in position against the sidewall 34 of the tire 12 by mechanical means, such as fasteners or dowel pins. A platen 88 (FIG. 7) is placed into contact with the mold body 72 to provide pressure and/or heat to the mold 70.

[0032] The mold body 72 remains in contact with the tire sidewall 34 as forming and curing of the dome 52 takes place. The pressure created in the mold cavity 74, the temperature created in the mold cavity and the amount of time that the mold body 72 is pressed against the tire sidewall 34 are all dictated by the specific elastomer or polymer that is selected for introduction into the mold cavity. For example, for most elastomers or polymers that may be is introduced into the mold cavity 74, the temperature in the cavity may be from about 150 to about 170 degrees Celsius and the molding time may be from about fifteen to about thirty minutes.

[0033] During the molding process, the elastomer or polymer in the mold cavity 74 flows about the fittings 40 and 42 in the cavity and the recess 54, and combines with the solid adhesive 66 and the flowable adhesive 68 to form the dome 52 shown in FIG. 8. In this manner, the dome 52 is formed as an integral component on the tire sidewall 34. The flowing of the elastomer, polymer and/or adhesive into the undercut 56 about the recess 54 creates a positive mechanical interlock of the dome 52 and the tire sidewall 34. The dome 52 is further secured to the tire sidewall 34 by the adhesive 64, 68.

[0034] The connecting member and method of forming the connecting member in an air maintenance tire 50 is efficient and reliable and produces a durable dome 52. The dome 52 includes a semi-rigid structure that is capable of flexing when needed, while being a stable structure that is formed on and securely attached to the sidewall 34 of the tire 12. Such a stable structure for the dome 52 preserves the connection of the annular air tube 20 to the connecting tubes 22 and 28 and maintains the integrity of the connection as the tire 12 rotates.

[0035] As described above, the present invention includes a method of forming a connecting member in an air maintenance tire 50. The method includes steps in accordance with the description that is presented above and shown in FIGS. 2 through 8.

[0036] It is to be understood that the structure of the above-described connecting member and/or the steps of the above-described method of forming the connecting member in an air maintenance tire may be altered or rearranged, or components or steps known to those skilled in the art omitted or added, without affecting the overall concept or operation of the invention.

[0037] The invention has been described with reference to a preferred embodiment. Potential modifications and alterations will occur to others upon a reading and understanding of this description. It is to be understood that all such modifications and alterations are included in the scope of the invention as set forth in the appended claims, or the equivalents thereof.