| 摘要 |
PURPOSE: To tightly hold a core on a mandrel and to make it readily removable by receiving an expandable friction core holder at selected points on a rotatable mandrel including a specific geometrical section. CONSTITUTION: A label friction mandrel 14, for example, is plurally provided on a rotating disc with protruding its one side and driven from the other side with a pair of longitudinal flat surface 16 formed on both sides. A core holder held by this mandrel 14 is composed of a pair of semicircle plate segments 20, 22 with an O ring 32 accommodated in a ring-shaped outer groove 30 on its outer circumferential surface, positioned across both inner circumferential surfaces of eccentric center holes 24, 26 when the mandrel 14 is turning, its diameter practically expanded by providing a step on the outer circumferential surface of both plate segments 20, 22, and the label is wound with the core tightly held through the O ring 32. When the mandrel 14 is reversely rotated, the O ring separates from the position between both center holes 24, 26 and practically reduces its diameter regarding the outer circumferential surfaces of both plate segments 20, 22 as an identical circle, thereby the core is readily removable. |
