Building drum for a tire belt-tread stock package

A tire building drum with an expandable and contractible building surface, said drum having means defining a longitudinal centerline for said building surface comprising:

• a plurality of drum segments having arcuate surfaces cooperative to define a cylindrical drum surface;
• a conical adjusting member coaxially positioned about the centerline;
• a plurality of slides connected to said conical adjusting member and supporting said drum segments in a circular array about the centerline;
• a plurality of radially extending guides connected to each slide and confining said slides to radial motion with respect to the centerline in response to motion of said conical adjusting member along the centerline;
• whereby axial motion of said cone along said centerline will move said drum segments concurrently radially toward and away from said centerline to change the effective diameter of the drum building surface defined by the drum segments;
• each of said annular drum segments having complementary scalloped edges extending axially of the drum structure and cooperating with the edges of adjacent drum segments to define a cylindrical surface of variable diameter which maintains some surface continuity in a direction longitudinally of the drum when the drum segments are moved to different radial positions.

A tire component building drum with an expandable and contractible building surface comprising:

• radially extending drum segments,
• means defining a centerline for the drum,
• means supporting said segments about said centerline and for adjusting the position of said segments radially of said centerline and
• said drum segments having arcuate outer surfaces and having interfitting non-linear edges extending generally lengthwise of the drum for defining a circumferential building surface of variable diameter depending upon the position of said segments.