| 摘要 |
1339586 Moulding grooves &c. in tubes POLVA-NEDERLAND NV 16 Dec 1970 [24 Dec 1969] 59748/70 Heading B5A In a device for shaping the end portion of a thermoplastics tube 3, a first mandrel portion 2 supports a shaping ring 4, the shaping ring being secured against sliding on the portion 2 by means of a sleeve-like portion 5, 6, slidably mounted on the first mandrel portion 2, the ring being fixed between an undercut 15 on the portion 2 and the sleeve-like portion, which is itself clamped in place against a shoulder 19 on the first mandrel portion by means of spring biased hooks 28; the shaping ring is of a material having a hardness between that of the tube material at ambient temperature and at the deforming temperature thereof. The hooks 28 are urged, against the action of springs 29, into the operative position shown, by a conical portion 26 on a rod 25 slidable within the bore of a tube 27 to which the first mandrel portion is fixed. The shaped tube may be removed from the device by first releasing the hooks 28, withdrawing the mandrel, and finally removing the sleeve and shaping ring from the tube. Cooling of the tube during moulding is effected by circulating cooling fluid through an annular recess 23 in the first mandrel portion 2. |
