GB871637A - Improvements in drive mechanisms for injection moulding machines - Google Patents

Abstract

871,637. Injection moulding machines. HEHL, A., HEHL, K., and HEHL, E., [trading as ARBURG FEINGERATEFABRIK O. H. G. HEHL-SOHNE]. March 26, 1959 [June 7, 1958], No. 10728/59. Class 87(2). Mechanism for moving and clamping together the mould parts of an injection moulding machine comprises a clamping plate guided for movement between a fixed clamping plate and thrust plate along parallel bars, a pneumatically or hydraulically operated drive unit which is movable about a pivot, the pivot being adjustably connected to the thrust plate to adapt the maximum opening distance between the clamping plates to the size of the mould, and linkage operatively connecting the drive unit with the movable clamping plate, the said pivot having its axis lying consistently in the mean plane of the mechanism. Air or hydraulic pressure in a cylinder 23 moves a clamping plate 4 along guide bars 2 without tilting it. The guide bars extend between the stationary clamping plate 1 and the thrust plate 5. Some of the components of the mould (not shown) are secured to the movable clamping plate and others to the stationary clamping plate. A pin 6 passes non- rotatably through the thrust plate 5 and is held in position by lock-nuts 7, 8. A double-armed lever 28 is pivoted at 9 to the pin 6 and forms part of a linkage, shown in Fig. 2 in the position where the clamping plates are opened, which comprises also links 17, 19, 21, with duplicate links at the rear, not shown. Pressure fluid in the cylinder 23 causes the piston-rod 30 to descend and the lever 28 to turn about the pivot 9 to a horizontal position, Fig. 1, with the result that the links 19, 21 swing apart, the cylinder 23 moving to a position where its axis is perpendicular to the guide bars. The divergent movement of the levers 17, 18 (not shown) relatively to the double-armed lever 28 is limited by an abutment 27 (which is integral with the double-armed lever 28 and connects its arms) engaging an abutment edge 38 formed on the pin 6. The closing movement of the levers 17 and 18, relatively to the double-armed lever 28, is limited by an abutment edge 39 on the abutment 7 engaging the pin 6. By shifting the pin 6 one way or the other and clamping it by the lock-nuts 7, 8 the distance between the clamping plates may be adjusted to the size of the mould.