An apparatus and method for simultaneously forming and filling a plastic container without the use of a mold forming a mold cavity (116, 16) is provided. A pressure source (120, 20) includes an inlet (146, 150, 46, 50) and a piston-like device (140, 40). The piston-like device (140, 40) is moveable in a first direction wherein liquid is drawn into the pressure source (120, 20) through the inlet (146, 150, 46, 50) and in a second direction wherein the liquid is urged toward the preform (112, 12). A blow nozzle (122, 22) may be adapted to receive the liquid from the pressure source (120, 20) and transfer the liquid at high pressure (P2) into the preform (112, 12) thereby urging the preform (112, 12) to freely expand until an unopened end thereof contacts a platen (118). The platen (118) forms a bottom in a resultant container. The liquid remains within the container as an end product.

A linear drive for a stretch and/or blow moulding machine has a force sensor for detecting actual force absorption of the linear drive during operation, a storage device in which data for a desired force absorption during operation are stored, and a comparison device for comparing actual force absorption with desired force absorption and a signal emitter for outputting a signal if a previously defined deviation between desired force absorption and actual force absorption is exceeded. Also provided is a method for determining a friction coefficient of a linear drive for a stretching and/or blow moulding machine, by determining a desired force absorption of the linear drive during operation, detecting using a force sensor, actual force absorption of the linear drive during operation, comparing actual force absorption with desired force absorption, and outputting a signal if a previously defined deviation between desired force absorption and actual force absorption is exceeded.

An apparatus and method for simultaneously forming and filling a plastic container without the use of a mold forming a mold cavity (116, 16) is provided. A pressure source (120, 20) includes an inlet (146, 150, 46, 50) and a piston-like device (140, 40). The piston-like device (140, 40) is moveable in a first direction wherein liquid is drawn into the pressure source (120, 20) through the inlet (146, 150, 46, 50) and in a second direction wherein the liquid is urged toward the preform (112, 12). A blow nozzle (122, 22) may be adapted to receive the liquid from the pressure source (120, 20) and transfer the liquid at high pressure (P2) into the preform (112, 12) thereby urging the preform (112, 12) to freely expand until an unopened end thereof contacts a platen (118). The platen (118) forms a bottom in a resultant container. The liquid remains within the container as an end product.

A linear drive for a stretch and/or blow moulding machine has a force sensor for detecting actual force absorption of the linear drive during operation, a storage device in which data for a desired force absorption during operation are stored, and a comparison device for comparing actual force absorption with desired force absorption and a signal emitter for outputting a signal if a previously defined deviation between desired force absorption and actual force absorption is exceeded. Also provided is a method for determining a friction coefficient of a linear drive for a stretching and/or blow moulding machine, by determining a desired force absorption of the linear drive during operation, detecting using a force sensor, actual force absorption of the linear drive during operation, comparing actual force absorption with desired force absorption, and outputting a signal if a previously defined deviation between desired force absorption and actual force absorption is exceeded.

In a method for operating an apparatus for transforming plastic preforms into plastic containers, the apparatus acts upon a flowable medium to plastic preforms in order to expand these plastic preforms to form the plastic containers, and the apparatus carries out this transforming operation while taking account of a plurality of process parameters. The plurality of process parameters is determined on the basis of a machine model, wherein a predefined number of input parameters are transferred to this machine model and at least one processor unit determines the process parameters and/or values characteristic of these process parameters on the basis of these input parameters.