Abstract: The most important heat-sealing parameters must be able to be adapted to different conditions of use in a simple and accurate manner. This is accomplished by the hot air temperature, on the one hand, and the amount of hot air, the speed of rotation of the pressing rollers (8, 9) and/or the pressing pressure of the pressing rollers (8, 9), on the other hand, being able to be controlled via controllers (41, 37, 24, 29), wherein a basic setting of the set points of these controlled variables is performed as a function of material- and/or application-specific characteristics, and by the position of the hot air nozzle (16) in terms of height (H), distance (A) and/or of the oncoming flow angle (.alpha.) with respect to the roller gap being able to be set by motor operators (18, 19, 21) as a function of the intended use and/or the thickness of the workpiece.

Abstract: A device for welding plastic foil strips together with a heating device and a pair of pressure rolls between which the strips are fed, includes a pressure device supported by a spring mechanism for one of two pressure rolls. The pressure device includes a first regulating mechanism for the setting of the width of the gap between the two pressure rolls and a second regulating mechanism for the setting of the welding pressure which is arranged on the first regulating mechanism and which can be moved by it. The regulating units of the two regulating mechanisms are two interacting eccentric elements. This leads to a compact design and only little force is necessary for the setting of the welding pressure.

Abstract: A welding machine for foil webs which are overlapped comprises an undercarriage which includes a rectangular frame having longitudinal frame members and laterally adjustable transverse frame members with wheels supporting the frame. A welding device is positioned on the frame and it in the frame includes centering elements which may be adjustable so as to position the welding device accurately in respect to the frame. The welding device itself advantageously includes slots extending inwardly from each side into which a respective foil end is positioned and roller means which engage with one of the foils for guiding it as the undercarriage is moved over the top of the respective foils to be welded together. The undercarriage during the welding device includes a drive from the wheels to the rollers which includes a shaft assembly having a plurality of universal joints.

Abstract: A device for separating a topmost workpiece from a stack of textile workpieces, comprises a table support which is guided for upward and downward movement and which is adapted to contain a stack of the workpieces and which is urged in an upward direction by weight means which are engaged with the table. In addition, a holding member is mounted for movement toward and away from the table and includes a lower end which is engageable on the top of the stack to hold the workpieces in position. A strip-off element, for example, a rotatable member having a plurality of radially extending bristles is engageable with the stack adjacent the holding member, and it is rotatable to direct at least the uppermost workpiece over the length of the holding member which is arranged in an inclined position over the stack. The holding member includes holding pins so that as the strip-off member moves upwardly over the holding member, it causes engagement of at least the uppermost workpiece with the pins.