| 摘要 |
A fluid expandable drum for building portions of tires in a tire building machine includes an annular supporting drum and an expandable annular tube element having an inner peripheral surface supported on the annular drum. The tube element includes an outer peripheral surface upon which building means is secured for movement therewith. The building means define an annular building surface thereon which is movable in a radial direction toward and away from the annular support drum upon contraction and expansion, respectively, of the tube element. The tube element is expanded to expand the diameter of the building surface to enable a tire portion to be built thereon and retracted to decrease the diameter of the building surface to enable a built tire portion to be removed therefrom. The tube element includes a radial ply extending around the cross-sectional circumference of the tube elements and a radial ply band extending around the outer peripheral surface of the tube element adjacent the building means to increase the strength and resiliency of the outer peripheral surface to enable the building means to decrease the diameter of the building surface upon contraction of the tube element without the need for auxiliary springs. |
