Patent GB-1520040-A (GB)
Title: Machines fot the manufacture of hollow bodies
IPC: B29C49/24
Filed: 1976-12-29
Abstract: 1520040 Heating blow-moulded parisons PONT-A-MOUSSON SA 29 Dec 1976 [31 Dec 1975 8 Dec 1976] 54193/76 Heading B5A An injection blow moulding machine comprises a polygonal turret 1 carrying a releasable set of parison cores 2 on each face, an oven C having a number of locations 4 for releasably mounting the sets of parison cores and movable in a closed circuit, and means for indexing the turret so that the sets of cores are located successively at a parison injection station A, optionally at a zone-blowing station B, at a station E for transferring a set of parison carrying cores to the oven C and removing a set which has passed the oven circuit, and at a final blowmoulding station D. The injection mould 53 is opened by a ram 55, Fig. 2, the turret is raised by a ram 15 acting through a lever 11 on its shaft 6 to raise the cores out of the lower mould half, and the turret is indexed through 90 degrees by a drive 16-17 to bring the parisons to the pre-blow mould 56, Fig. 6. The tip 18 of the core 2 is mounted on a tube 23 which is displaced by a pusher rod 26 having a recessed member 25 into which a pin 35 on the tube 23 enters when the turret is lowered again. The mould 56 is closed and cooling fluid (e.g. air, water or CO 2 ) from a conduit 31 passes through orifices 30 into and along the tube 23, through orifice 32 into and back along the space 33 between the tube 23 and the core wall, and out through a conduit 34. Then the core tip 18 is extended to produce an annular opening for escape of blowing air into the parison from a conduit 36 connected to the end of the tube 23. The mould 56 is opened and the turret is raised and indexed to next position where the oven C is advanced by a ram 63 so that the set of cores enters one of its cavities 4. The plate 3 is locked to the oven by rotation of a half cylindrical member 68 (Fig. 9, not shown) into a groove (19) in the plate 3. the core plate 3 is unclamped from the turret, and the oven is rotated 60 degrees to bring a heated set of parisons to the turret. The plate 3 of this set is clamped to the turret and the oven is moved back so that it is withdrawn from its cavity 4. The turret is indexed to the final blow-moulding station D where the parisons are inflated in a manner similar to the pre-blowing, the core tip 18 having extended to stretch the parison into contact with the bottom of the mould to produce biaxial orientation. The parisons are heated in the oven by hot air supplied from a central manifold through radial tubes 67 in which the parisons are located. The core mounting plates 3 have enlargements at each end, one rectangular, the other with an oblique face (Fig. 3, not shown). These enlargements slide through clamping members (42, 43) as the turret is raised and lowered at the transfer station E. When in position the plate 3 is clamped by drawing the clamping members against the side of the turret against a spring bias. Upper and lower locating clamps 44, 45a, Fig. 25, are operated simultaneously by rotation about spindles 103 by a ram 98a. The upper clamps 45a may have passages 89 for supply of cooling and blowing fluid to openings 90 in the core support plate 3.