The present invention provides a method and apparatus for forming an apex filler (13). The invention also provides a method and apparatus that is uniquely adapted for applying an apex filler (13) onto a bead ring sub-assembly (14) without the introduction of stresses at the outer edge (50) of the apex filler (13). The apex filler forming apparatus (10) works in conjunction with an extruder (43) which presents a linear strip (42) of elastomeric material having a pre-determined cross-section. A pair of opposed, forming rollers (33) present a nip (35) therebetween. Means (36) are provided to rotate the rollers (33). Rotation of the forming rollers (33) causes the nip (35) frictionally to engage the elastomeric strip (42). The interaction between the elastomeric strip (42) and the nip (35) effects rotary motion of the elastomeric strip (42) and increases the circumferential length of the elastomeric strip (42) proportionally to the radial distance outwardly from the base (49) thereof. The apex forming mechanism (10) is operative in conjunction with an apex filler applying apparatus (11) to apply the apex filler (13) formed from the elastomeric strip (42) onto the radially outer surface (46) of a bead ring sub-assembly (14). Mounting chucks (21) are provided to position and rotatably support the bead ring sub-assembly (14) while the apex filler (13) is applied thereto.
A method and an apparatus for manufacturing a bead filler which does not deteriorate the uniformity of a pneumatic tire are provided. The apparatus extrudes a rubber composition at a surface velocity V.sub.1 in a top portion 28 and at a surface velocity V.sub.2 in a base portion 26, while forming the rubber composition in the shape of a filler portion 24 in a forming portion 40 by a truncated cone shaped extruding roller 38. The filler portion 24 formed in a curved shape similar to a shape of a side portion of a tire is formed due to the difference in velocity between the surface velocities V.sub.1 and V.sub.2. The filler portion 24 is successively joined to and wound around an annular bead core from a winding start end, and is disposed in the side portion of the tire after forming the bead filler.
A structure and a method for supplying a bead-with-filler automatically to a tire molding machine are provided. The structure comprises a bead-with-filler preset apparatus for presetting a filler to an annular bead; a bead supply apparatus positioned at an upper stream side of the bead-with-filler preset apparatus for supplying the annular bead to the bead-with-filler preset apparatus; a bead-with-filler supplying apparatus positioned at a down stream side of the bead-with-filler preset apparatus for supplying the bead-with-filler to a tire molding machine; and a transfer apparatus for transferring the bead and the bead-with-filler having a catching section. The transfer apparatus turns for positioning the catching section at each delivery position of the bead supply apparatus, the bead-with-filler preset apparatus and the bead-with-filler supply apparatus.
A rubber element for tire comprising a bead core which is generally an annular shape, and an apex which is generally an annular shape and attached to the bead core. The apex comprises a first portion whose sectional configuration is generally a rectangle, and a second portion whose sectional configuration is generally a semiellipse and integrally molded on an outer face of the first portion. An inner face of the first portion of the apex is attached to an outer face of the bead core, whereby the apex and the bead core are united.
A method and apparatus are provided for a sub forming an elastomeric extrusion into a bead apex filler and for applying the same to an annular bead (120) to form a bead/apex subassembly for use in the construction of a pneumatic tire. The apex filler (100) is formed from a triangular shaped extrusion (8) that is initially wrapped around a rotating mandrel (40) having a diameter of between about 50% to about 75% of the outer diameter of the annular bead to which the filler is attached. A helical former (50, 60) disposed around the mandrel causes the extrusion to move in a helical path as it traverses the mandrel. As the extrusion is removed from the mandrel, the extrusion is sufficiently uncoiled to relieve and compressive or tensile stresses. Then, the partially uncoiled extrusion is wrapped around the outer periphery of the bead to form a bead/apex filler subassembly (118) which is substantially without compressive or tensile stresses when mounted onto the tire being constructed.
The present invention is intended to prevent the residual stress from remaining in an apex. An apparatus for automatically assembling a bead apex according to the present invention comprises: a means for joining both the longitudinal ends of a strip apex having a triangular section with one short side and two long sides and a specified length to each other, and for forming the strip apex in a cylindrical body such that the long sides become the inner and outer peripheral surfaces; a means for forming the cylindrical body into a disk-like shape such that the short side becomes the inner peripheral surface and the long sides become the axial end surfaces; and a means for joining the inner peripheral surface of the disk-like apex to the outer peripheral surface of a bead ring.
