Drum holder

Claim 1

A cylindrical holder adapted to receive upon its peripheral cylindrical surface a snug wrapping of a removable sheet material and substantially continually take up slack as generated in said wrapping during rotation of said holder in use applications, and comprising: i. a cylindrical drum rotatable about its axis, ii. an axially-parallel elongated key chamber within the body of said drum and spaced from the axis thereof, said key chamber having a radially outward wall, iii. an axially-parallel slit in the periphery of said drum, said slit being radially advanced from the radial location of said key chamber as said drum is rotated in use applications, iv. an axially-parallel passage between said slit and said key chamber, one side wall of said passage forming a substantially acute-angle leading-edge structure with the periphery of said drum and the other side wall of said passage forming a substantially obtuse-angle following-edge structure with the periphery of said drum, said radially outward wall of said key chamber being disposed on the side of said passage where said leading-edge structure is located, v. an elongated key member in said elongated key chamber, said key member being adapted to serve as a holder for the trailing portion of a sheet material as wrapped about the periphery of said drum with the trailing Portion of said sheet material extending over said following-edge structure of said drum to said key member, vi. pinching means for holding the leading portion of a sheet material as wrapped about the periphery of said drum with the leading portion of said sheet material extending over said leading-edge structure of said drum into said key chamber between said key member and said radially outward wall, said pinching means being formed by said key member pressing against said radially outward wall of said key chamber as said drum is rotated in use applications, said pinching means being operable independently of the holding action of said key member on said trailing portion of said sheet material, and vii. means for applying torque upon said key member as said drum is rotated in use applications, said means comprising a centrifugal weight on an arm extending radially outward from said key member, with said weight so disposed upon rotation of said drum in use applications to cause torque on said key member in a rotary direction opposite to that of said drum rotation, whereby slack generated in said sheet material during rotation of said drum is substantially simultaneously taken up by torque-caused rotary motion of said key member, and whereby such torque-caused rotary motion of said key member is in a rotary direction opposite to that causing ejection of the leading portion of said sheet material from its pinched position between said key member and said radially outward wall of said key chamber.