| 摘要 |
1. Method of manufacturing lamp covers (2) with a vertical rim (8) for long fluorescent lamps, in which a preheated, thermoplastic plate- or tape-shaped (continuous sheet or strip) material (19) with portions projecting on all sides is inserted into a stretch die (1) consisting essentially of two die halves and is processed in said stretch die (1) by mechanical and pneumatic reshaping, with slides (15) being brought, during the closing of the stretch die (1), from a withdrawn position into an advanced position forming the marginal area of the die nest plate (14) and with the projecting rim or waste strip (25) being cut off by cutting edges (9, 26) provided on said stretch die (1), characterized in that the plate- or tape-shaped material (19) becomes clamped between the undersides (24) of said slides (15) and holding-down means (10), as well as between the inner sides, facing each other, of said slides (15) and the outer sides of a clamping plate (12) forming said vertical rim (8) and that, after that, prior to the termination of the closing movement said waste strip (25) is cut off by the lowering of the second die half (4) over the first die half (3). |
