GB1314160A - Method and apparatus for clamping mould parts together - Google Patents

Abstract

1314160 Die casting machines KATASHI AOKI 27 May 1971 [30 May 1970] 17543/71 Heading B3F [Also in Division B5] Apparatus for clamping mould parts 1, 2 together when a mould support 3 is moved toward a mould support 4 includes at least one hydraulie piston and cylinder assembly 5 located between the supports such that during mould closure, with a control valve 12 in the position shown, in Fig. 3, fluid from below the piston in each cylinder is forced to the spaces above such pistons and, since the latter spaces are smaller in volume, excess fluid is fed to a pressure accumulator 10. When the mould parts are abutted, Fig. 2, the control valve is brought to the position shown whereby fluid remaining in the lower spaces of the cylinders is connected to a pressure accumulator 11, which is at a lower pressure, via a check valve 15 and, since the accumulator 10 is at a higher pressure, the pistons are urged downwardly to clamp the mould parts together. Alternatively the assemblies 5 may be replaced by single active piston and cylinder assemblies arranged to urge the supports 3, 4 together and supplied by separate pumping means, such as a single acting piston and cylinder located between the supports and arranged during movement of support 3 towards the support 4, to displace fluid to the upper spaces of said single acting piston and cylinder assemblies and the higher pressure accumulator.