| 摘要 |
PURPOSE:To enable efficient manufacture of a product of high quality, by a method wherein plastic is used to previously mold an upper drum cylinder and a bottom plate and the upper and the lower end part of a net cylinder are forced to cut into the upper drum cylinder and the bottom plate by high frequency induction heating as the net cylinder is pressed in a condition to nip the net cylinder from above and below by the use of the two parts. CONSTITUTION:An upper drum cylinder 1 consists of a main cylinder 2, having its lower peripheral part coupled to a net cylinder 6, and an auxiliary frame 3 snapped with the upper end of the main cylinder 2. In manufacture, plastic is used to previously mold the main cylinder 2, the auxiliary frame 3, and the bottom plate 5, and after the net cylinder 6 is coupled to the main cylinder 2 and the bottom plate 5, the auxiliary frame 3 is engaged with the main cylinder 2. The net cylinder 6 is disposed such that, after a beltlike net piece made of a metal is bent and both ends are nipped with the aid of an U-shaped metal piece 7 to form a cylinder, upper and lower ends 6a and 6b are mated with the inner peripheries of cylinder walls 2b and 5b, respectively. Under this condition, the net cylinder 6 is heated by a coil connected to a high frequency generator, and this causes the upper and lower ends 6a and 6b to cut into the main cylinder 2 and the bottom plate 5. |
