Patent ID: 7491050

Claim:
A mold clamping unit, comprising: a fixed first platen; a movable second platen; a drive mechanism for implementing a displacement of the second platen; at least one length-adjustable threaded connection for adjusting a mold height, wherein the threaded connection is comprised of a threaded spindle and a spindle nut which is arranged on the threaded spindle and supports one of the first and second platens, for transmitting a stroke and transmitting a locking force, when the second platen assumes a clamping position; and a clamping mechanism locking the spindle nut in relation to the threaded spindle and being selectively releasable for length adjustment of the threaded connection, with the clamping mechanism including a clamping nut, which is connected in fixed rotative engagement with the spindle nut and coupled for slight axial displacement in relation to the spindle nut, and an actuator, which is switchable between an active position, in which the spindle nut is braced with the clamping nut by a tightening force so that the one of the platens is urged against the spindle nut, and an idle position, in which the actuator is released and which is implementable irrespective of a stroke position of the drive mechanism, wherein the threaded spindle and the one of the platens are coupled to each other directly via the spindle nut for transmitting the clamping and locking forces, and via the actuator for transmitting an opening force in opposition to the tightening force applied by the actuator.