| 摘要 |
A pair of hemi-cylindrical drum segments are formed by a pair of semicircular end panels which are joined to, and spaced-apart by, a side wall having a hemi-cylindrical wall section and a substantially rectangular planar wall section. The planar wall section of one drum segment defines a longitudinally oriented re-entrant groove which unites with a longitudinally oriented tongue protruding from the planar wall section of the other drum segment. - The tongue and groove are united with one another, an overall cylindrical drum structure will result. The closely adjacent planar wall sections of each drum segment establish a diametrical parting plane when the tongue and groove are united with one another while the hemi-cylindrical wall segments are provided with longitudinally spaced-apart and outwardly protruding pairs of roll stops close to this parting plane. |
