SIDEWALL CONSTRUCTION FOR A TIRE

Abstract

A bead portion of a tire includes a bead core, a first bead filler arranged at a radially outer side of the bead core, a first carcass extending around the bead core and the first bead filler, a second carcass extending radially inward and adjacent the first carcass, a second bead filler disposed axially adjacent the second carcass, a first chafer disposed at an axially outer side of the second bead filler, a second chafer extended about a radially inner end of the first carcass, and a flipper extending radially inward from a position axially adjacent an axially outer side of the first bead filler. The flipper further extends axially inward adjacent a radially inner side of the bead core. The flipper further extends radially outward to position axially adjacent a first part of the first carcass, a second part of the first carcass, the second carcass, and a radially outermost end of the first bead filler.

Claims

1. A bead portion of a tire comprising: a bead core; a first bead filler arranged at a radially outer side of the bead core; a first carcass extending around the bead core and the first bead filler, the first carcass extending radially inward adjacent an axially inner side of the bead core, extending axially outward adjacent a radially inner side of the bead core, and extending radially outward adjacent an axially outer side of the bead core; a second carcass extending radially inward and adjacent the first carcass; a second bead filler disposed axially adjacent the second carcass; a first chafer disposed at an axially outer side of the second bead filler; a second chafer extended about a radially inner end of the first carcass; and a flipper extending radially inward from a position axially adjacent an axially outer side of the first bead filler, the flipper extending axially inward adjacent a radially inner side of the bead core, and the flipper extending radially outward to position axially adjacent a first part of the first carcass, a second part of the first carcass, the second carcass, and a radially outermost end of the first bead filler.

2. The bead portion as set forth in claim 1 wherein the flipper extends radially outward beyond the radially outermost end of the first bead filler.

3. The bead portion as set forth in claim 1 wherein the second bead filler extends axially between the second carcass and the first chafer.

4. The bead portion as set forth in claim 1 further including a toe guard extending between the first chafer and the second chafer.

5. The bead portion as set forth in claim 1 further including a toe guard extending between the first carcass and the second carcass.

6. A method for stiffening a bead portion of a tire, the method comprising the steps of: arranging a first bead filler at a radially outer side of a bead core; extending a first carcass around the bead core and the first bead filler; extending the first carcass radially inward adjacent an axially inner side of the bead core; extending the first carcass axially outward adjacent a radially inner side of the bead core; extending the first carcass radially outward adjacent an axially outer side of the bead core; extending a second carcass radially inward and adjacent the first carcass; arranging a second bead filler axially adjacent the second carcass; arranging a first chafer at an axially outer side of the second bead filler; extending a second chafer about a radially inner end of the first carcass; extending a flipper radially inward from a position axially adjacent an axially outer side of the first bead filler; extending the flipper axially inward adjacent a radially inner side of the bead core; and extending the flipper radially outward to position axially adjacent a first part of the first carcass, a second part of the first carcass, the second carcass, and a radially outermost end of the first bead filler.

7. The method as set forth in claim 6 further including the step of terminating a radially innermost end of the second carcass axially between the first carcass and a toe guard.

8. The method as set forth in claim 6 further including the step of extending the flipper radially outward beyond the radially outermost end of the first bead filler.

9. The method as set forth in claim 6 further including the step of extending the second bead filler axially between the second carcass and the first chafer.

10. The method as set forth in claim 6 further including the steps of: extending a toe guard between the first chafer and the second chafer; and extending the toe guard between the first carcass and the second carcass.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0087] FIG. 1 is a schematic cross sectional view along a tire radial direction and a tread width direction of a tire in accordance with the present invention.

[0088] FIG. 2 is an enlarged cross sectional view of part of the tire of FIG. 1.

DESCRIPTION OF EXAMPLES OF THE PRESENT INVENTION

[0089] In the following description of the drawings, the same or similar reference numerals are used to designate the same or similar parts. It may be appreciated that the drawings are schematically shown and the ratio and the like of each dimension may be different from these examples. Therefore, the specific dimensions must be determined in view of the below explanation. It is needless to say that relations and ratios among the respective dimensions may differ among the diagrams.

[0090] FIG. 1 shows a cross sectional view of a pneumatic or non-pneumatic tire 1 along a tire radial direction and a tread width direction of the tire in accordance with the present invention. The tire 1 may be mounted on a standard rim 100. The tire 1 may have a normal inner pressure and support a normal load. The tire 1 may include a tread portion 3, a bead portion 5, and a side wall portion 7. The tread portion 3 may contact a road surface (not shown).

[0091] The tire 1 may further include two bead portions 5 (one shown), a first carcass 30, a second carcass 32, a side rubber layer 60, and a belt portion 90. The first carcass 30 may be arranged throughout the tread portion 3, the bead portion 5, and the side wall portion 7. The first carcass 30 may extend between a pair of the bead cores 10 (one shown) and a pair of the first bead fillers 20 (one shown). The first carcass 30 may curve radially inward to the axially inner side of the bead cores 10 and the first bead fillers 20 and wrap around the axially outer sides of the bead cores 10.

[0092] The second carcass 32 may be arranged throughout the tread portion 3, the bead portion 5, and the side wall portion 7. The second carcass 32 may curve radially inward to the axially inner side of the bead cores 10. The second bead filler 40 may be arranged at the axially outer side of the first carcass 30 and the second carcass 32.

[0093] The example bead portion 5 may be attached to, or in contact with, the rim 100. The side wall portion 7 may interconnect the tread portion 3 and the bead portion 5. The bead portion(s) 5 may include a bead core 10, a first bead filler 20, a second bead filler 40, a first chafer 50, a reinforcing layer 70, a second chafer 80, and a toe guard 91.

[0094] The bead core 10 may allow the attachment of the tire 1 to the rim 100. The bead core 10 be constructed of bead wire (not shown). The first bead filler 20 may be arranged at the radially outer side of the bead core 10. The first bead filler 20 may have an approximate triangular shape.

[0095] The first chafer 50 may be arranged at the axially outer side of the bead portion 5. More specifically, the first chafer 50 may be arranged at the axially outer side the second carcass 32 and the second bead filler 40. A side rubber layer 60 of the side wall portion 7 may be arranged at the axially outer side of the first carcass 30 and the second carcass 32. A second chafer 80 may extend axially between the first carcass 30 and the second carcass 32. The second chafer 80 may prevent toe chipping at the rim 100. A belt layer 90 may be arranged in the tread portion 3 at the axially outer side of the first carcass 30. The belt layer 90 may include, for example, two belts.

[0096] As shown in FIG. 2, the bead portion 5 may include the bead core 10, the first bead filler 20, the first carcass 30, the second carcass 32, the second bead filler 40, the rubber chafer 50, the reinforcing layer 70, and the second chafer 80. The bead core 10 may have a bead core-innermost surface 15 which is an innermost surface of the bead core 10 in the tire radial direction. Further, the bead core 10 may have a bead core-outermost surface 17 which is an outermost surface of the bead core 10 in the tire radial direction.

[0097] The first bead filler 20 may have a first bead filler outer end portion 23 which is an outer end portion in the tire radial direction of the first bead filler 20. As illustrated in FIG. 2, the thickness of the first bead filler outer end portion 23 may be reduced toward the outer side in the tire radial direction, that is, the first bead filler outer end portion, which is an outermost end of the first bead filler 20 in the tire radial direction. An inner end portion in the tire radial direction of the first bead filler 20 may contact the bead core 10.

[0098] The first carcass 30 may have an inner first carcass 30a positioned at the inner side in the tread width direction and an outer first carcass 30b curved to the outer side in the tread width direction. The outer first carcass 30b may be positioned at the outer side in the tread width direction from the inner carcass 30a. An outer carcass outer front end 35, which is an outermost end in the tire radial direction of the outer carcass 30b, may contact the inner carcass 30a. Between the inner first carcass 30a and the outer first carcass 30b, the bead core 10 and the first bead filler 20 may be arranged.

[0099] The second carcass 32 may be arranged at the outer side in the tread width direction of the outer first carcass 30b while contacting the outer first carcass 30b. An outer end portion in the tire radial direction of the second carcass 32 may be positioned proximate/adjacent the side wall portion 7.

[0100] The second bead filler 40 may be positioned at the outer side in the tread width direction from the outer first carcass 30b. The second bead filler 40 may have a second bead filler outer end portion 43, which is an outer end portion in the tire radial direction, and a second bead filler inner end portion 48, which is an inner end portion in the tire radial direction. As illustrated in FIG. 2, the thickness of the second bead filler 40 may be reduced toward the end portion of the second bead filler 40 in the tire radial direction from the center of the second bead filler 40 in the tire radial direction. That is, the thicknesses of the second bead filler outer end portion 43 and the second bead filler inner end portion 48 may be thinner than that of the center of the second bead filler 40.

[0101] The second bead filler 40 may extend both axially and radially beyond the first bead filler outer end portion 23 in the tread width direction. Accordingly, the second bead filler 40 overlaps the first bead filler outer end portion 23 in the tread width direction. An outermost end of the second bead filler outer end portion 43 in the tire radial direction may be positioned at the outer side in the tire radial direction radially outward from the first bead filler outer front end 23. The second bead filler inner end portion 48 may be positioned at a radially outer side of the bead core 10. Accordingly, the second bead filler inner end portion 48 may be positioned at the outer side in the tire radial direction from the bead core-outermost surface 17. The second bead filler 40 may contact the second carcass 32 at the inner side in the tread width direction. The second bead filler 40 may contact the rubber chafer 50 at the outer side in the tread width direction.

[0102] The rubber chafer 50 may be arranged at the outer side in the tread width direction of the second bead filler 40. The rubber chafer 50 may be exposed at the outer side in the tread width direction of the overall bead unit 5. A rim line 150 may be formed at an exposed portion of the rubber chafer 50. The rubber chafer 50 may have a rubber chafer outer end portion 55 which is an outer end portion in the tire radial direction. The rubber chafer outer end portion 55 may have different heights in the tire radial direction at the inner side in the tread width direction and the outer side in the tread width direction. At the rubber chafer outer end portion 55, a rubber chafer width direction-inner end may be positioned at the inner side in the tread width direction and may have a height in the tire radial direction, which is higher than that of a rubber chafer width direction-outer end positioned at the outer side in the tread width direction. That is, the rubber chafer width direction-outer end may be so positioned at the inner side in the tire radial direction from the rubber chafer width direction-inner end. The rubber chafer outer end portion 55 may approach the inner side in the tire radial direction as it extends toward the outer side in the tread width direction.

[0103] In the tread width direction, the rubber chafer 50 may extend outward of the second bead filler 40. Accordingly, the rubber chafer outer end portion 55 may be positioned at the outer side in the tread width direction from the second bead filler outer end portion 43. More specifically, the rubber chafer width direction-inner end may be positioned at the outer side in the tread width direction from the second bead filler outer end portion 43. The inner end portion of the rubber chafer 50 in the tire radial direction may contact the rim 100 at a rim flange 110. The rubber chafer 50 may be constructed of a rubber-like member with a density lower than that of the second bead filler 40. Further, the loss tangent of the second bead filler 40 may be smaller than that of the rubber chafer 50. The side rubber layer 60 may contact the second carcass 32 at the inner side in the tread width direction. The side rubber layer 60 may contact the rubber chafer outer end portion 55 at the inner side in the tire radial direction.

[0104] In accordance with the present invention, the reinforcing layer 70 may wrap around the bead core 10 and extend radially outward from the radially inner side of the bead core 10. In the tread width direction, the reinforcing layer 70 may have an axially inner layer 70a positioned at the inner side of the bead core 10 and an axially outer layer 70b positioned at the outer side of the bead core. A radially outer end 75a of the axially inner layer 70a may extend radially outward to a position axially adjacent the inner first carcass 30a, the outer first carcass 30b, the second carcass 32, and the first bead filler outer end portion 23. A radially outer end 75b of the axially outer layer 70b may extend radially outward to a position adjacent the first bead filler 20.

[0105] The reinforcing layer, or flipper 70, of the present invention may increase cornering stiffness of tire 1 thereby enhancing dynamic operating conditions, such as ride & handling performance of the tire. Further, such a flipper 70 may provide little or no negative impact to rolling resistance of the tire 1 or other factors, such as manufacturing complexity and cost.

[0106] The foregoing and other objects, features, and advantages of the present invention will be apparent from the above detailed descriptions of examples of the present invention, as illustrated in the accompanying drawings wherein like reference numbers represent like parts of the present invention. Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims.