Process for controlling the parallelism of the two beams of a press used for cutting sheet or weblike matter destined to be converted into a package

A method for regulating parallelism of two beams of a cutting press designed for converting sheet or weblike matter into a package, comprising the steps of:

• providing the press with a frame made of a lower crossbar and an upper crossbar connected to one another by means of lateral posts, an upper fixed beam being mounted to the upper crossbar and a lower movable beam being raised and lowered with each operating cycle by a drive system having bearings connected to the lower crossbar;
• during an operating cycle of the press, measuring a deviation from parallelism e when the drive system is situated in an upper dead center position;
• and
• when a lower dead center position is reached, vertically shifting said bearings so as to have the lower beam tilt in a direction contrary to a tilt resulting from the deviation from parallelism e measured in the upper dead center position so as to regulate parallelism of the lower beam with respect to the upper beam.

A cutting press for converting sheet or weblike matter into a package, comprising:

• a frame made of a lower crossbar and an upper crossbar connected to one another by lateral posts;
• an upper fixed beam fitted on the upper crossbar;
• a lower movable beam and drive system means for raising and lowering the lower movable beam with each operating cycle, the drive system being supported by bearings connected to the lower crossbar;
• means for moving said bearings vertically when the drive system is situated in a lower dead center position so as to regulate a parallelism of the lower beam with respect to the upper beam;
• proximity sensor means for measuring parallelism of the two beams when the upper and lower beams have been moved together to a pressure contact position for cutting the sheet or weblike matter;
• position sensor means for determining a position of said means for moving the bearings;
• said means for moving the bearings comprising wedges and a motor means for shifting the wedges;
• and
• control means having a closed loop for each motor means by which it is possible to feed in a position command value common to all position sensor means for regulating an operating pressure of the press, and said control means having a parallelism command value for at least one position sensor means for regulating parallelism of the two beams with respect to one another, said parallelism command value being derived from the measured parallelism of the proximity sensor means for said pressure contact position.

A system for regulating parallelism of upper and lower beams of a cutting press having cutting tools and designed for converting sheet or weblike matter into a package, comprising:

• means for permitting movement of at least one beam with respect to the other beam between a first position in which the two beams are separated from one another, and a second position in which the cutting tools are in pressure contact with the matter to be cut;
• means for measuring a deviation e from parallelism of the beams when they are in the second pressure position;
• and
• means for regulating the parallelism of the beams in a direction enabling a correction of the measured deviation e from parallelism when the beams are in the first position and separated.