Patent Application
20110146887
The invention relates to tire ply and method of manufacturing tires.
Tires are typically comprised of one or more layers of ply. The one or more plies are typically applied in a sheet form onto a tire building drum. The sheet of ply is wrapped about the drum, cut to the desired length and then assembled together. Prior to being brought to the drum, the ply composite must go through a lengthy component preparation process. The first step in the process is to form ply fabric at a fabric facility. At this facility, a fabric comprised of longitudinal ply cords 5 are made into a long continuous sheet 1, as shown in
Thus an improved method and apparatus for forming a splice that does not require an additional investment in capital equipment is described.
The invention provides in a first aspect a method of forming a layer of tire ply comprising the following steps: providing a sheet of ply having a first and second lateral ends to be joined together; wherein said sheet of ply formed of a plurality of functional reinforcement cords and having two or more “dummy” spacer cords at each later end; overlapping the first and second lateral end so that the dummy cord of one of said ends is located adjacent a functional cord of the second of said ends.
The invention provides in a second aspect a method of forming a layer of tire ply comprising the following steps: providing a sheet of ply having a first and second lateral ends to be joined together; said sheet of ply formed of a plurality of functional reinforcement cords and having two or more dummy spacer cords at one of said ends; overlapping the first and second lateral end so that the dummy cords of one of said ends is located adjacent the functional cords of the second of said ends.
A third aspect of the invention may utilize a plurality of lower strength and less stiff cords in the lateral ends of both pieces of ply in the overlapped B region. These cords may be roughly half as strong and half as stiff as the remainder of the ply cords. Once layered, these cords would have strength and stiffness comparable to the remainder of the ply sheet.
“Aspect Ratio” means the ratio of a tire's section height to its section width.
“Axial” and “axially” means the lines or directions that are parallel to the axis of rotation of the tire.
“Bead” or “Bead Core” means generally that part of the tire comprising an annular tensile member, the radially inner beads are associated with holding the tire to the rim being wrapped by ply cords and shaped, with or without other reinforcement elements such as flippers, chippers, apexes or fillers, toe guards and chafers.
“Belt Structure” or “Reinforcing Belts” means at least two annular layers or plies of parallel cords, woven or unwoven, underlying the tread, unanchored to the bead, and having both left and right cord angles in the range from 17° to 27° with respect to the equatorial plane of the tire.
“Bias Ply Tire” means that the reinforcing cords in the carcass ply extend diagonally across the tire from bead-to-bead at about 25-65° angle with respect to the equatorial plane of the tire, the ply cords running at opposite angles in alternate layers
“Breakers” or “Tire Breakers” means the same as belt or belt structure or reinforcement belts.
“Carcass” means a laminate of tire ply material and other tire components cut to length suitable for splicing, or already spliced, into a cylindrical or toroidal shape. Additional components may be added to the carcass prior to its being vulcanized to create the molded tire.
“Circumferential” means lines or directions extending along the perimeter of the surface of the annular tread perpendicular to the axial direction; it can also refer to the direction of the sets of adjacent circular curves whose radii define the axial curvature of the tread as viewed in cross section.
“Cord” means one of the reinforcement strands, including fibers, which are used to reinforce the plies.
“Inner Liner” means the layer or layers of elastomer or other material that form the inside surface of a tubeless tire and that contain the inflating fluid within the tire.
“Inserts” means the reinforcement typically used to reinforce the sidewalls of runflat-type tires; it also refers to the elastomeric insert that underlies the tread.
“Ply” means a cord-reinforced layer of elastomer-coated, radially deployed or otherwise parallel cords.
“Radial” and “radially” mean directions radially toward or away from the axis of rotation of the tire.
“Radial Ply Structure” means the one or more carcass plies or which at least one ply has reinforcing cords oriented at an angle of between 65° and 90° with respect to the equatorial plane of the tire.
“Radial Ply Tire” means a belted or circumferentially-restricted pneumatic tire in which the ply cords which extend from bead to bead are laid at cord angles between 65° and 90° with respect to the equatorial plane of the tire.
“Sidewall” means a portion of a tire between the tread and the bead.
“Laminate structure” means an unvulcanized structure made of one or more layers of tire or elastomer components such as the innerliner, sidewalls, and optional ply layer.
The invention will be described by way of example and with reference to the accompanying drawings in which:
A first embodiment of the present invention is shown in
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.
