| 摘要 |
PURPOSE:To prevent the sealing of a vessel opening from breaking by forming a shell and disposing a liner on the inner side of the top face part of the shell then forming an annular groove in the skirt part. CONSTITUTION:Pressing or drawing is applied to a metal blank material to form an approximately cup-shaped shell 6 having a circular top face part 2 and a cylindrical skirt part 4 suspended from the circumferential edge of this circular top part 2. Next, if necessary, upper knurling 12a and lower knurling 12b as well as slits 4 are formed in a skirt part 4. Next, the shell is positioned inverted on a cradle 26a and a liner blank material 8a made of synthetic resin material is supplied to the predetermined position on the inner side of the top face part of the shell 6. A die holding tool 28 is then lowered from above the shell 6 and is inserted into the shell 6. In this way, the liner blank material 8a is formed by die pressing to a required shape. Next, an annular groove 10 extending circumferentially is formed in the skirt part 4 of the shell 6 by the cooperation of an inner side tool 30 and an outer side tool 32, whereby the vessel cover is produced. |
