Patent GB-1258187-A (GB)
IPC: B29C49/00
Filed: 1969-03-11
Abstract: 1,258,187. Injection-blow moulding. R. HAGEN, [trading as KAUTEX-WERK REINOLD HAGEN]. 11 March, 1969 [12 March, 1968; 6 Sept., 1968], No. 12873/69. Heading B5A. An injection-blow moulding apparatus comprises ,a fixed mounting plate 14, Fig. 2, a reciprocable mounting plate 15, at least one pair of injection mould halves 12a, 12b, one of each pair being carried by each mounting plate, at least one pair of blow-mould halves 13a, 13b, one of reach pair being carried by each mounting plate, a pair of oppositely extending blowing and injection mandrels 16 for each pair of injection and blow moulds, the mandrels being rotatable to transfer them from one mould to the other. Injection cylinder 10 injects material into injection cavity to form parison 33 while article 36 is blown in blow mould 13 by means of air supplied through mandrel 16, the valve stem of which is extended by bushing 52 movable into recess of mandrel mounting 17 and through which air may be supplied. Plate 15 is moved to open the moulds by means of non rotatable stems 61 operated through motor (not shown), pinion 63 and threaded nut 62. Hydraulic cylinder 66 effects initial opening and final locking movement. Mounting 17 and mandrels 16 thereon are rotatable about shaft 18. On opening of the moulds, mandrels 16 are carried with upper mould halves 12a, 13a and plate 15 until pin 25 on shaft 18 abuts frame 31, pushing shaft 18 against spring 29, descending relative to plate 15 which continues to open the moulds. Rotation is effected by means of rack 23, pinion 22 and sleeve 19 engaging splined shaft 18 by means of springs 21 when opening is completed and the mandrels 16 are thus positioned halfway between the open mould halves. Bushes 52 are removed from their recesses before rotation. After blowing, the products 36 may be stripped from the mandrels 16 on rotating by means of stripper arm (34, Fig. 1, not shown) In the alternative embodiment of Figs. 5, 6 (not shown), mandrel mounting member 17 with mandrels 16 thereon is lowered from plate 15 as soon as the opening movement commences by means of resilient rack-and-pinion arrangement (194-199) but at half the speed of plate '15. An alternative stripping mechanism (Fig. 7 not shown) comprises a stripper sleeve (291) around the mandrel (216) cammed outwardly by means of its groove (292) against the action of spring (293) on opening of the blow-mould. In a further alternative arrangement (Figs. 8, 9, not shown), hydraulic mould opening devices (366, 366<SP>1</SP>) are mounted on the fixed plate (314) operating the movable plates (315, 315<SP>1</SP>) through piston-rods (361, 361<SP>1</SP>), members (331, 331<SP>1</SP>) and spars (386, 386<SP>1</SP>). Injection is effected vertically from head (310a). Rotation and opening movement of mandrel mounting member (317) is effected similarly to that in Fig. 2, using stop member (331a). The spars (386, 386<SP>1</SP>) may carry channels for supply of blowing air to the bushes (352) and for supply of heating and/or cooling medium to the mould halves. Additional -stripper -sleeves (391) may be provided on mandrels (316) connected by members (374) which is moved by pressure cylinders (376) fed through shaft (318) and arranged at the sides (Figs. 8-10) or centre (Figs. 11, 12) of mounting (317). Further strippers (334, Figs. 8, 13, not shown) may be provided comprising two fingers (334a) which are close together for stripping or openable by cylinder (385) to allow passage of parisons through them. A delivery tube (303, Fig. 9) is provided.