Abstract: A film stretching machine is also capable of shrinking undulating film by gripping film to be treated at its longitudinal edges by pivotable clips which are disposed spaced apart on a chain conveyor and are guided in a chain conveyor guide. The film is shrunk by a longitudinal adjustment of the film areas lying between the gripping members of neighboring clips. In the apparatus, the longitudinal adjustment or shrinking occurs in that each clip is constructed as a pivoting clip and includes a rolling part on which the gripping part is mounted so as to be pivotable about an axis which is disposed parallel to the film plane.

Abstract: A tentering chain is equipped with a mechanism for the stepless, continuous adjustment of the chain pitch which is the on-center spacing between two neighboring chain link journal bolts or pins. Such chains are used for this simultaneous, biaxial treatment of synthetic material films or webs. For this purpose, the chains carry tenter bodies with hooks or clamps for gripping the film edge. The tenter bodies carry guide rollers which engage guide rails along the travel path of the tentering chain. In order to dimension the tenter body with its gripping elements as small as possible, while still permitting a large shrinking or stretching of the film web, the chain link journal bolts or pins are mounted in the respective tenter body for an adjustment of the pin position in a direction of the chain travel. In all positions of the journal pin or pins these pins extend perpendicularly to the longitudinal direction of the chain.

Abstract: A tentering chain is guided between two guide rails extending in parallel to each other. One guide rail (19a) is an outer guide rail with regard to a course followed by the chain, while the other guide rail (19b) is an inner guide rail. The chain links are hinged to each other by a journal pin which carries a first guide roller on an inner pin section between chain link plates, and a second guide roller on a cranked outer pin section. Thus, the rotational axes of these two guide rollers extend in parallel to each other and spaced from each other, so that one guide roller can only contact one guide rail, but not the other and vice versa. This feature prevents the reversal of the rotation direction of the guide rollers as they travel along the parallel guide rails.

Abstract: A tentering chain has a continuously adjustable chain pitch for the simultaneous biaxial treatment of film webs. Tenter bodies conventionally equipped with clamps or hooks for gripping an edge of the film web are carried by the tentering chain. Guide rails operate the tenter clamps. Neighboring tenter bodies are interconnected by chain links. Each chain link is connected by a hinging connection at each end to the respective tenter body. At least one of the two hinging connections of a chain link is adjustable by a hinging bolt having an eccentric section or sections and a circular section or sections. The adjustable eccentric hinging bolts are mounted for rotation in the tenter bodies and the eccentric section engages the respective end of the chain link. For this purpose the chain link has a bore in which the eccentric section is received.

Abstract: An apparatus for simultaneously treating film webs biaxially is described. Film edges are clamped into tentering clamps running around in an endless track. The individual tentering clamps are interconnected with one another by an upper and a lower chain, whereby the connection between two successive tentering clamps is respectively established by two chain links loosely interconnected with each other. The loose chain links can be brought in pairs into a lengthwise extending arrangement or into a kinked arrangement and vice versa, with the aid of control rails arranged outside of the chain track cooperating with a chain link formed as a bellcrank. In this manner the spacing between two successive tentering clamps is shortened or alternatively lengthened. Thus, it is possible to achieve a lengthwise variation in the film web being treated, and especially to adjust a fine shrinking ratio.

Abstract: A material dryer, especially for bulk material, includes a single entrance pressurized drum housing and an endless conveyor for passing the material through the drum housing. The conveyor may include a screen belt. The housing and the dryer components in the housing are divided into identical modular units, except for the entrance and discharge units. Each modular unit includes a tubular housing section, a conveyor section, and a treatment medium handling section for circulating and heating the drying medium such as super-heated steam. The heating and circulating of the treatment medium is individually controllable in each modular unit. The entrance unit is equipped with conveyor belt guides and with a sealed material supply device. The discharge unit is equipped with a belt drive and with a sealed material discharge device.

Abstract: In a film stretching machine having tentering chains travelling in an endless loop, the forward advance tracks of the tentering chains are laterally adjustably arranged within the machine housing for adjusting to fit different material web widths and for adjusting the lateral or widthwise stretching ratio. The tentering chain reversal guide arrangements at the inlet and outlet ends of the machine are correspondingly laterally slidably adjustable. The return tracks for the tentering chains are arranged outside of the housing in a fixed position and orientation relative to the housing. Straight transition guide portions pivotally connect the stationary return chain tracks to connection points of the respective laterally movable reversal guide arrangement. The straight transition guide portions are each articulated at one end to the respective return chain track and at the other end to the respective reversal guide arrangement. The return chain tracks may be either open or completely closed channels.

Abstract: In a blower arrangement for blowing a gaseous treatment medium onto a longitudinally moving material web, nozzle plenums are arranged above and below the web and extend essentially perpedicularly to the transport direction of the web. Each nozzle plenum is divided lengthwise into two channels arranged one above the other by means of a horizontal partition wall. At one end of the nozzle plenum, both channels are simultaneously supplied with treatment medium flow, whereas at the other end, both channels are interconnected for flow between them. The lower channel including the blower nozzles is further divided by a diagonally extending vertical separation wall forming two complementary wedge-shaped tapering partial chambers which both simultaneously supply treatment medium to the blower nozzle or nozzles.

Abstract: A film stretching machine with tentering hook chain tracks extending through several consecutive processing zones is constructed of preassembled standardized exchangeable structural groups permitting a modular type of construction. These structural groups include venting cells of the same kind which are fully pre-equipped and are arranged along the left and right edges of the film web to be stretched. Exchangeable blower boxes with nozzle fingers or arms having a standardized width are installable between opposite venting cells of a processing zone. The dimensions of the venting cells are matched to the dimensions of typical shipping containers in order to achieve efficient packaging possibilities. The length of the venting cells advantageously corresponds to two or three times a standard spacing of adjustment spindles used for adjusting the spacing of the tentering hook chain tracks. The width of the standardized blower boxes may vary stepwise by twice the width of the venting cells.

Abstract: The guide track for a tentering chain carrying roller-supported tenter clips or clamps has two band-shaped flexible parallel guide rails extending horizontally along the edge of a material web, but protruding in an upright or on-edge manner perpendicular to the material web. The tenter clips have running rollers arranged in the material tentering plane and contacting respective opposite vertical surfaces of the guide rail arranged closer to the material web for taking up horizontal forces. The tenter clip reaches around the two guide rails in a C-shape so that an upper support roller contacts the upper edge of the guide rail lying closer to the material web for supporting the weight of the tenter clip and so that a lower support roller contacts the lower edge of the other guide rail for taking up any tipping or tilting moments of the tenter clip.

Abstract: A guide track for a tentering chain carrying tentering clamps supports the clamps by a number of rollers to form a tentering frame, especially for a film stretching machine. The guide track is an endless track with U-turns in which a single semicircle type of U-turn has been replaced by a U-turn including two partial curved sections each having a smaller radius of curvature and the two curved sections are interconnected by a straight intermediate section. The reversing or looping curved section at the beginning of the reverse run is so constructed that at this location a drive sprocket wheel can mesh with the tentering chain. Thus, the drive sprocket which was a source of contamination for the web is located remote from the web to thereby substantially reduce any possibilities of contaminating the web.