Two-platen closing system for an injection molding machine
AssigneeKrauss-Maffei Kunststofftechnik GmbH
InventorWalter Wohlrab
Life of this patent
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Abstract
In a two plate closing unit of an injection molding machine the stationary and the movable mold mounting plates are connected by columns, wherein the columns that traverse the fixed mold mounting plate are fixedly connected to a clamping cylinder in which the columns configured at their ends as pressure plungers configured for generating a clamping pressure reciprocate, and while some of the clamping plungers are dual action plungers, the clamping plungers are coupled to a spindle drive and drive unit, such that the spindle drive is at the same time the control drive for a stepped plunger and the closing force and the closing and opening motion is realized by a single drive which operates the spindle and the plunger cylinder unit.
Claims5
A two-platen closing unit for an injection molding machine comprising:
- a fixed mold mounting plate;
- a moving mold mounting plate;
- a plurality of columns received in the moving mold mounting plate and traversing the fixed mold mounting plate, each said column slidingly supported in the fixed mold mounting plate and having a clamping plunger received in a clamping cylinder, thereby defining a clamping pressure compartment, whereby the clamping pressure compartments in the clamping cylinders are in hydraulic communication with one another, wherein a first plurality of clamping plungers is configured as a dual-action plunger which divides the clamping cylinder into the clamping pressure compartment and an opening pressure compartment and includes a flow passage for connecting the clamping pressure compartment with the opening pressure compartment;
- a spindle drive coupled to a second plurality of clamping plungers and having spindles connected in driving relationship with a hydraulic piston and cylinder drive for feeding a hydraulic pressure medium into the clamping pressure compartments of the second plurality of clamping plungers, wherein the hydraulic piston and cylinder drive defines a pressure compartment;
- a flow control valve disposed in the flow passage and including a stem-like valve body which closes the flow passage in a first operative position and clears the flow passage in a second operative position;
- a pilot valve interacting with the valve body to control the first and second positions of the valve body;
- a shut-off connection line for fluidly connecting the pressure compartment of each spindle drive with the clamping pressure compartments, and
- a pressure source connected to the opening compartments for ensuring a minimum pressure.
Dependencies are inferred from the claim text.