| 摘要 |
1,219,516. Seaming. DYNAMIT NOBEL A.G. 19 Dec., 1968 [22 Dec., 1967], No. 60517/68. Heading B5K. Two blocks 1, 2 of foamed resilient synthetic. thermoplastic material are welded in end-to-end relationship by pressing the blocks 1, 2 together, causing a parting means 8 to move between the blocks so as to form a moving space behind the means 8, heating and softening the end faces of blocks in the region of the moving space, and, when the space has moved on, allowing the softened region of the end faces to come into contact and to become welded to each other. In one embodiment, Figs. 1 and 3b, the blocks 1, 2 are clamped by devices 3, 4 on tables 5, 6 which are slid towards each other so that the end faces to be welded are pressed together. A welding device comprising the parting means 8, in the form of a wedge, and an electrically heated wire 9 is forced between the block ends with the wedge 8 leading so that the wire 9 heats the end faces partly by radiation and partly by contact. Preferably, the wedge 8 is coated with a lubricant, e.g. silicone oil. Pairs of supporting rolls 11 may be arranged behind the wedge 8. The wire 9 may be replaced by an electrically heatable rod or tube. In another embodiment, Fig. 4b, the wedge 8 is replaced by a leading roller 12 and following pairs of supporting rollers 12 arranged in wedge form. A supporting column 8a is provided. In a further embodiment, Fig. 5a, the parting means comprises two solid wedge-shaped members 17a, 17b arranged side-by-side with a channel therebetween. A pair of bands 13, 14 pass through the channel and around the members 17a, 17b and each band is attached at one end to a fixed clamp 15, 16 and at the other end to a movable device 20. In use, the parting means is brought into its starting position prior to pressing the blocks 1, 2 together. The device 20 pulls the members 17a, 17b followed by rollers 18 and a heating wire 19 between the blocks 1, 2. The members 17a, 17b may be braked by weights attached to the rear of the apparatus. |
