Patent ID: 9662847
Date: 2017-05-30
CPC Classifications: B29D

Claim:
1. A tire building drum comprising: a central shaft extending along an axial dimension of said tire building drum; a pair of opposing hub units surrounding said central shaft and movable along said axial dimension toward and away from one another; a plurality of first scissor linkages disposed in a radial configuration about said central shaft, each of said first scissor linkages comprising first and second links, each first link having a first end pivotally and slidably mounted to one of said pair of hub units, each second link having a first end pivotally and slidably mounted to the other of said pair of hub units, said first and second link first ends being biased toward a median plane of said central shaft, whereby movement of said hub units toward one another through a first range of motion of said hub units moves respective second ends of each said first and second links radially outwardly from said central shaft to a radially outward limit of movement of said first scissor linkages, and movement of said hub units toward one another through a second range of motion of said hub units causes slidable movement of said first ends of each of said first and second links in relation to said hub units absent radially outward movement of said second ends of each of said first and second links; a plurality of second scissor linkages disposed in an alternating configuration between said first scissor linkages about said central shaft, each of said second scissor linkages comprising third and fourth links, each third link having a first end pivotally connected to one of said pair of hub units and each fourth link having a first end pivotally connected to the other of said pair of hub units, whereby movement of said hub units toward one another through said first and second ranges of motion of said hub units moves respective second ends of each said third and fourth links radially outwardly from said central shaft; a plurality of first deck segments, each said first deck segment supported by one of said first scissor linkages and disposed radially outwardly of said corresponding linkage; and a plurality of second deck segments, each said second deck segment supported by one of said second scissor linkages and disposed radially outwardly of said corresponding linkage; whereby when said hub units are separated from one another, said second deck segments are disposed radially inwardly of and between said first deck segments, whereby movement of said hub units toward one another through said first range of movement of said hub units expands said first deck segments to an expanded diameter of said tire building drum, and whereby movement of said hub units toward one another through said second range of movement of said hub units expands said second deck segments to allow said second deck segments to be received between said first deck segments.