| 摘要 |
The invention provides means for producing a moulded plastics ball having the appearance of a conventional ball with a continuous curved seam. In order to make the moulding seam (parting-line) as inconspicuous as possible, the invention provides a mould assembly comprising two mould members, having mutually confronting surfaces each surrounding a part-cavity, a generally spherical mould cavity being defined when the confronting surfaces are in contact with one another, lip portions of said surface defining a continuous parting line around a diametral zone of the cavity, said parting line having four portions, comprising two substantially S-shaped portions with two at least substantially straight-line portions, said portions being arranged alternately around the diametral cavity zone, each portion of the line meeting its adjacent portion to include an angle of not substantially less than a right-angle.
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