Patent GB-929361-A (GB)
Title: Mold assembly with power device for opening and handling multiple section molds
IPC: B29C43/00
Filed: 1961-05-01
Abstract: 929,361. Transfer moulding-mould handling. J. E. BORAH. May 1, 1961 [Aug. 12, 1960], No. 15715/61. Class 87(2). A multiple section mould assembly, Fig. 4, comprises upper and lower mould plates 50, [a] 56 intermediate mould plates 52, 54, and vertically reciprocable rails 110, 112 for supporting and moving the intermediate plate 54 laterally out of its position between the plates 52, 56. The apparatus is mounted on a base (not shown), with four corner posts (as 30, 32) which support a fixed platen 60. A lower platen 26 is reciprocable on the corner posts by a hydraulic cylinder (not shown) to open and close the mould plates, which are aligned as they close by pins 72, 74, 76. Mould cavities 66 with cores 68, Fig. 5, e.g. for gaskets, are formed between the closed plates, and in operation moulding material e.g. rubber is placed on the plate 52, which is a pot well plate having sprues 70 connecting with the cavities 66. As the platen 26 is raised, it carries the lower plate 56, which is fixed to it, firstly into contact with the intermediate plate 54, and finally closes the pot well plate 52 against the fixed upper plate 50, which forces the material into the cavities 66. The plates are then returned to the positions shown in Fig. 4 and the plate 54 is slid manually on the rails 110, 112 from between the plates 52, 56 to a position where lugs 138, 140, Fig. 6, coincide with slots 146, 148, in the rails. This enables the plate 54 to be inverted by revolving it on pins 142, 144 to the position shown in Fig. 6 when it is slid back so that the lugs 138, 140 engage in the ends of the rails 110, 112. Alternatively the lugs may be fitted at the other end of the plate, i.e. if Fig. 6 illustrates the normal position of the plate 54 then an inversion about the pins 142, 144, the lugs 138, 140 will enter the slots 146, 148. The moulded articles are removed from the cavities in the plate 54 either manually or by a push-out device, Fig. 15, which comprises a rectangular platform 220 secured to extensions 125, 126 of the platen 60. This platform supports a hydraulic cylinder 216 with a piston rod 214, which is connected to a plunger 212 reciprocable on fixed guide rods 246. As the plunger 212 is moved into contact with the plate 54 it pushes the articles therefrom into a receptacle or on to a conveyer (not shown). The platform 220 is supported on extensions 230, 232, 234, 236 fixed to it and is slidable on the extensions 125, 126 and lockable thereto by screws 238. A tray 248 for mouldable material may be fitted on the plunger 212 within easy reach of an operator. Two wedge-shaped members 260, Fig. 24, are screwed into contact with the edges of plate 54 at one end as shown, keeping that end clear of the rails 110, 112. The other end rests on the rails so that the pins 142, 144 are taken out of contact with the rails and the pressure exerted by the push-out device is taken up by the rails. Alternatively, the members 260 may be V-shaped and fit into V-shaped grooves in the sides of the plate 54. After unclamping the plate 54 it is slid back between the plates 52, 56, its position being determined by fixed stops (not shown) fitted in the ends of rails 110, 112. The rails 110, 112, are reciprocable vertically by the use of four piston rods (as 114, 118) Fig. 4 of hydraulic cylinders (as 121, 123). Alternatively the cylinders (as 121, 123) may only be operable to effect downward movement of the rails 110, 112 and thus the plate 54. The rods 114, 118 are adjustable for length at 114<SP>1</SP>, 118<SP>1</SP> to accomodate different thicknesses of the plate 54. The pot well plate 52 is guided for vertical movement by four rods (as 80, 82) which pass through the platen 60 and carry springs 202 into contact with adjustable plugs 204 in the tops of fixed cylinders (as 88, 90). The springs serve to effect proper separation of the plates 50, 52 as the platen 26 is lowered. The lower plate 56 may be also moved out laterally on rails 160, 162, Figs. 4, 20, to facilitate the loading of inserts (e.g. steel rings, beaded chains, or annular coil springs, for incorporation in the moulded articles) on to the plate 56. The plate 56 may be reciprocated by a hydraulic cylinder 172, its rod 176 being connected to the plate 56 by a flexible coupling 178. In presses where only one intermediate plate is used, Fig. 20, the upper plate 294 may also be slid out on rails (as 290) by the use of two hydraulic cylinders (as 296) to facilitate the removal of unwanted sprue from the upper plate. The plates of the mould assembly may be heated electrically or by steam to cure the moulding material and the movements of the plates may be controlled by an operator or carried out automatically.