Patent GB-794730-A (GB)
Title: Machine for blowing bottles and other hollow articles from organic plastic materials
Inventor: STRONG BERNARD
IPC: B29C49/04
Filed: 1955-02-23
Abstract: 794,730. Blow-moulding plastic bottles &c. SHIPTON & CO., Ltd., E. Feb. 23, 1956 [Feb. 23, 1955], No. 5430/55. Class 87(2). Plasticized material is fed by a motor-driven screw 3, Fig. 2, to a distributer valve 20 which delivers the material to one or other of two nozzles 17 through which it is extruded in tubular form into blowing moulds supported by tables 22. Compressed air is fed through pipes 18, Fig. 1, to blow the tubular lengths of plastic material to form hollow articles within the moulds. The distributer valve 10 is moved from one delivery position to the other by means of a double-acting air-operated cylinder 44, and the air supply to this cylinder and the air used for blowing are derived from the same source of compressed air-as shown, from a reservoir 36. The air supply from 36 to 44 is controlled by a valve 45 which is manually operated by means of a handle 46. The blowing air supply to pipes 18 is by way of pipe 62, valve 19 and pipes 63. The valve 10 comprises a tapered plug 11 having two outlets 14a, 14b at right angles to each other, the plug being turned about its vertical axis to present these outlets in turn to horizontal conduits 15 which lead to the nozzles 17. The plug is turned by successive movements of the rod 43 of cylinder 44. The screw 3 is turned by an electric motor 26 through a clutch 28 and when a tube has been extruded from say the right-hand nozzle, Fig. 1, the screw is stopped by disengagement of the clutch, which is effected by handle 35, compressed air valve 34, cylinders 32, 33 and lever 29. In operation a mould is then closed around the extruded tube and the plug 11 is turned through a right-angle by means of handle 46, valve 45, cylinder 44, rod 43, crank arm 41 and plug stem 40. This turning movement does two things, viz. it prepares the valve for subsequent extrusion through the left-hand nozzle and it turns on the blowing air supply to the pipe 18 of the righthand nozzle, this turning-on being effected by means of an arm 43a which is secured to rod 43 and is connected to the valve 19. A bottle &c. is thus blown in the mould under the right-hand nozzle. The handle 35 is again operated, first to engage clutch 28, whereupon a tube of plastic material is extruded from the left-hand nozzle, and then to disengage the clutch, and a mould is closed around the tube. Then the handle 46 is operated to turn plug 11, whereby blowing air is turned on to the left-hand nozzle and off from the right-hand nozzle, whereupon the blown bottle &c. in the right-hand mould may be removed. This sequence is then repeated. Each mould, Fig. 3, is in two parts 55 hinged together about a vertical axis and having tubecutting portions 56, 57. The platform 22 on which a mould rests has an aperture 59 through which the lower part of the extruded tube depends. Each nozzle and mould may be duplicated, as in Fig. 4, spaces 61 being provided to accommodate the lower parts of the extruded tubes. In a modification (not illustrated) the air valves 19 may be operated independently of the valve 11.