Rubber bead forming tool for molding beads onto emergency running wheels for tires has axially movable actuators with edge curve profile which moves segments radially outwards to create forming ring

摘要

Individual segments(22.1-22.3,24.1,24.2) are connected to an operating mechanism(26) which can be moved axially inside a ring(28) formed by the segments. The operating mechanism is connected to each segment through actuators. Each actuator has an axial curved profile to determine segment movements. Axial movement of the operating mechanism moves segments from one position in which they form a small diameter to a second position in which they form a larger diameter closed circular ring. Segment actuators form a star shape with a central axis. Edges of the segments form the axial curved profiles. The segment ring(28) comprises inner, smaller(24.1,24.2) and outer, larger(22.1-22.3) segments. Actuators assigned to the inner segments have a curve profile different to the curve profile of the outer segment actuators. Curve profiles comprise sections at different angles to the axis. Segments are located on both sides of a supporting disc and are axially movable. Star-shaped grooves in the supporting disc guide slides which connect via pins with the profiled edge of each segment actuator. The supporting disc comprises two discs, in each of which corresponding cut outs form the guide grooves for slides. Axial curve profiles of actuators assigned to inner segments have a first section with a low incline, a second section with a steeper incline and a third section parallel to axis of the operating mechanism. Axial curve profiles of outer segment actuators have a first section with a low incline and a second section parallel to the axis. Axial movement of the segment operating mechanism during a first phase moves inner and outer segments simultaneously. During a second phase the outer segments remain stationary while inner segments move at higher speed between the outer segments. In a third phase inner and outer segments form the complete segment ring(28) and are retained in this position.