| 摘要 |
1,175,524. Making hollow articles. DUNLOP CO. Ltd. 5 Dec., 1966 [15 Dec., 1965], No. 53343/65. Heading B5A. Hollow articles, such as table-tennis balls, are made by forming hemispheres in a sheet, dividing the sheet into two, superimposing the two halves of the sheet so that the hemispheres are in alignment and finally welding and cutting the material around the peripheries of the hemispheres to form separate balls. In the apparatus shown in the Figure, the sheet having hemispheres formed therein is moved by edge engaging grippers (not shown) over a lower assembly comprising a spring-biased rear plate 422 and an apertured vertically reciprocable forward plate 425. An upper assembly 401 is then lowered on to the sheet causing spring biased pads 407 to engage the corner hemispheres in the rear half of the sheet and the blade 409 to sever the sheet into two. The assembly 401 is then withdrawn and the plate 425 lowered whilst the grippers are rotated through 180 degrees to turn the forward half of the sheet upside down. Plate 425 is then re-raised to almost contact the forward half of the sheet, after which the rear half of the sheet is pushed forward to a position overlying the forward half of the sheet by a pusher 418 carried by a slide 405 movable on the assembly 401. Just before the pusher contacts the rear half of the sheet, arms (not shown) carried by the slide 405 engage and open the grippers to allow the forward half of the sheet to fall on to the plate 425. The thus superimposed sheets are then gripped by another set of grippers and removed to a welding and cutting device. |
