Abstract: A pinning device for the electrostatic pinning of a film on a chill roll is disclosed having a first coil unit, a second coil unit, a pinning region situated between the coil units, a high-voltage source as well as at least two electrodes. At least the first electrode of at least two electrodes is strip-shaped. The electrodes run from the first coil unit to the second coil unit in the pinning region and high voltage is applied to both electrodes by the high-voltage source.

Abstract: An improved method and an associated improved device for operating a linear-motor-driven simultaneous stretching installation is distinguished inter alia by the following features: during normal operation, the linear-motor-driven transporting units in the simultaneous stretching zone are subjected to an acceleration phase with a normal-operation acceleration profile involving a growing increase in the distance from a following transporting unit driven by the linear motor drive; when the web of material is moved into the stretching zone, at least two leading tenters, following one another and driven by the linear motor, are accelerated in the stretching zone in such a way that differs from the normal-operation acceleration profile that the distance formed between the at least two tenters following one another and driven by the linear motor is less than 80% or less than 75% of the distance that is brought about during normal operation.

Abstract: An improved method and an associated improved device for operating a linear-motor-driven simultaneous stretching installation is distinguished inter alia by the following features: during normal operation, the linear-motor-driven transporting units in the simultaneous stretching zone are subjected to an acceleration phase with a normal-operation acceleration profile involving a growing increase in the distance from a following transporting unit driven by the linear motor drive; when the web of material is moved into the stretching zone, at least two leading tenters, following one another and driven by the linear motor, are accelerated in the stretching zone in such a way that differs from the normal-operation acceleration profile that the distance formed between the at least two tenters following one another and driven by the linear motor is less than 80% or less than 75% of the distance that is brought about during normal operation.

Abstract: An improved multiple-screw extruder, in particular a twin-screw extruder comprises a housing. Several housing bores are located in at least one section within the housing. The housing bores overlap at least along a partial axial length of the housing. One extruder screw is arranged in each of the several housing bores. At least two motors are provided for the at least two extruder screws. A synchronizing and torsion transmitting device, by means of which both cooperating extruder screws can be synchronized, is provided on both the inlet side and the discharge side.

Abstract: An improved multiple-screw extruder, in particular a twin-screw extruder comprises a housing. Several housing bores are located in at least one section within the housing. The housing bores overlap at least along a partial axial length of the housing. One extruder screw is arranged in each of the several housing bores. At least two motors are provided for the at least two extruder screws. A synchronizing and torsion transmitting device, by means of which both cooperating extruder screws can be synchronized, is provided on both the inlet side and the discharge side.

Abstract: A device drives a preheating roll assembly comprising several rolls, during a heating or preheating stage. A motor assembly includes at least one individual drive and preferably two individual drives, which are used to drive at least the exit roll and preferably the entry roll and the exit roll. The motor assembly also includes one or more asynchronous motors, each asynchronous motor controlling the surface speed and the torque of one of the intermediate rolls. A common frequency converter operates one or more asynchronous motors, in particular all asynchronous motors.

Abstract: The invention relates to an improved device for driving a preheating roll assembly comprising several rolls, during a heating or preheating stage. Said device is characterized as follows: the motor assembly comprises at least one individual drive and preferably two individual drives, which are used to drive at least the exit roll and preferably the entry roll and the exit roll; the motor assembly also comprises one or more asynchronous motors, each asynchronous motor controlling the surface speed and the torque of one of the intermediate rolls; and a common frequency converter operates one or more asynchronous motors, in particular all asynchronous motors.

Abstract: The invention relates to a method and to a circuit arrangement used to regulate synchronous linear motors, especially linear drive mechanisms in film drawing systems. The force (Fclip) between the stationary primary part and the moved secondary part is determined in a sensorless manner from the voltages and currents calculated and measured in a frequency converter in a functional block, in such a manner that the integral is calculated from the active power during a time period (tclip) between two pulses (new—clip) produced by an overriding control and said integral is divided by the active length (1zone) of the primary part. Alternatively, the force (Fclip) can also be determined by summation of the voltages in the f-axis in order to reduce the drop in voltage in relation to the resistance (Rstr) of the branch in the primary part. Voltages and currents are transformed on the primary part by a co-ordinate system related to the secondary part.

Abstract: The invention relates to a method and to a circuit arrangement used to regulate synchronous linear motors, especially linear drive mechanisms in film drawing systems. The force (Fclip) between the stationary primary part (20) and the moved secondary part (30) is determined in a sensorless manner from the voltages and currents calculated and measured in a frequency converter (10) in a functional block (11), in such a manner that the integral is calculated from the active power during a time period (t,clip) between two pulses (new_clip) produced by an overriding control and said integral is divided by the active length (lzone) of the primary part (20). Alternatively, the force (Fclip) can also be determined by summation of the voltages in the f-axis in order to reduce the drop in voltage in relation to the resistance (Rstr) of the branch in the primary part (20). Voltages and currents are transformed on the primary part (20) by a co-ordinate system related to the secondary part (30).

Abstract: In a linear-motor-driven transport installation, in particular a linear-motor-driven simultaneous stretching installation, the tenter-clip carriage return section (10) is divided into at least three zones, namely a first speed-changing zone (17), a following transporting zone (19) and a subsequent braking zone (21). The length of the speed-changing zone (17) and the braking zone (21) is together less than 40% of the overall length of the return section (10). Only in the speed-changing zone (17) and/or braking zone (21) are more powerful drive devices provided than in the other part of the return section (10), in order to subject the carriages there to a more intense change in speed.

Abstract: An improved control device for linear-motor-driven equipment, in particular for the drive of tenters of a film stretching plant, has a central control device (1) and a multiplicity of converters (11) that are activated thereby, at least indirectly. An improvement is achieved by a phase profile, which describes a relationship between the phase angle, the current amplitude and a clock pulse, for activating the stator winding (7) in a relevant zone (5), being able to be predefined for the converters (11), and by the corresponding phase-profile data for the activation of the stator winding (7) being able to be calculated and/or generated in the converters (11). In addition, a synchronization device, via which the time signals in the converters can be synchronized with one another during operation, is provided.

Abstract: An improved apparatus for adapting speed, in particular for nippers (1) which can be made to travel along a rail arrangement (3), is distinguished by the following featuresa rotating and electrically conductive eddy-current body (17), preferably designed in the form of an eddy-current wheel or an eddy-current cylinder, is provided,the guide rail arrangement (3) runs at least over and away from a partial region of the eddy-current body (17) with a tangential component,on the carriages (1) which can be made to travel along the guide rail arrangement (3) there is provided or can be excited at least one magnet (7a, 7b), which is arranged on the side facing the eddy-current body (17) and, in the region of the eddy-current body (17), can be moved over and away from the eddy-current body (17), with an air gap being formed.