Abstract: A corrugated cardboard manufacturing machine (10) wherein at least one continuous supporting belt (11) for supporting/conveying a sheet of cardboard is moved along a predetermined path by actuating means (13); and where the supporting belt (11) is defined by a mat of multispiral fabric (1) preferably made of synthetic polymer fibers.

Abstract: The present invention discloses folded corrugated material for producing segments or strips for use as Easter grass, packing material and the like or for use as flower pot covers, floral wrappings and ribbon materials.

Abstract: The present invention discloses folded corrugated material for producing segments or strips for use as Easter grass, packing material and the like or for use as flower pot covers, floral wrappings and ribbon materials.

Abstract: The invention relates to a stack of fan folded material and related systems and processes. The stack includes at least two clips of fan folded material. Each clip includes a plurality of fan folded sheets, with each sheet joined to at least one adjacent sheet by a weakened line. Each clip is joined to an adjacent clip by a last sheet of one clip being interfolded with or adhesively joined to a first sheet of a succeeding clip.

Abstract: A manufacturing method for a filter element having a filter portion and a flange portion formed along an outer periphery of the filter portion to protrude outwardly. First, a corrugated intermediate product having plural ridges of the filter element is formed by folding. Next, the flange portion is formed integrally with the filter portion by pressing an outer peripheral portion of the intermediate product at a high temperature. While the flange portion is formed, each of sides of the intermediate product extending in parallel with the ridges is restricted to a position corresponding to a shape of the filter element by plural forming jigs. Therefore, sides of the flange portion extending in parallel with the ridges are formed simultaneously when the flange portion is formed and do not need to be trimmed after forming. As a result, a material of the filter element is less wasted.

Abstract: Damping system for corrugated cardboard fabrication rollers comprising the incorporation of a damping device in the vapour chamber (2) of the application roller (1), said device being mounted integral with respect to the wall of the corresponding roller (1) so that the vibrations affecting the roller (1) are transmitted to the device, the vibration of the incorporating device being opposed to the vibration of the roller (1) as a result of the action-reaction principle thereby damping the vibration of the roller (1).

Abstract: A device for ply-bonding tissue products comprising first conveying means for a first single/multi-ply tissue web; as well as a roll pairing (22, 30; 22, 28), one roll of which is an embossing roll (22; 28); and one of the two rolls (22; 28) has spikes (26) on the shell surface cooperating with a companion roll (30; 28; 22) of high rubber hardness. The two rolls are adapted in location and length of the spikes (26) so that the spikes perforate both the first tissue web (14) and the second tissue web (16) in the nip of the roll pairing.

Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient by utilizing a thin walled roll shell so that it is capable of inward deflection in the corrugating nip in order to cushion impact and absorb the deflection as the rolls interengage along the nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise level and roll wear and improves the quality and consistency of corrugation. A modified flute profile, compensating for flute pitch variations between the large diameter bonding roll and small diameter corrugating roll, assures uniform flute-to-flute engagement in the corrugating nip.

Abstract: The present invention discloses folded corrugated material for producing segments or strips for use as Easter grass, packing material and the like or for use as flower pot covers, floral wrappings and ribbon materials.

Abstract: A variable heat transfer system and a passive, segmented hold-down mechanism for a preheater section and a hotplate section of a machine for manufacturing corrugated board. The preheater assembly having the variable heat transfer system includes a plurality of actuators to urge a continuous web of material toward a preheater drum. A sacrificial material is positioned between the web of material on the preheater drum and the actuators. In response to moisture detection in the material by a plurality of sensors, one or more of the actuators applies variable pressure in the cross-machine direction to the wet portion of the material. Also, the passive, segmented hold-down mechanism includes a plurality of independently weighted feet for varying a variable pressure profile in the cross-machine direction formed upon the web of corrugated board. The hold-down mechanism compensates for variations in the contour of the surface of the hotplate section.

Abstract: On a machine frame, a machine for the lengthwise treatment of webs of corrugated board comprises a pair of tool beds, on which several tool holders are disposed for displacement by means of a threaded spindle. The tool holders each support a tool. The number of tool holders exceeds the number of threaded spindles. Each tool holder has a spindle nut, which is disposed on the threaded spindle and is mounted rotatably in the tool holder. It can be non-rotatably coupled with the tool holder by means of a clutch.

Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient so that it is capable of inward deflection in the vicinity of the corrugating nip in order to cushion impact as the rolls interengage along the corrugating nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise levels, roll wear and improves the quality and consistency of corrugation.

Abstract: A method of imparting directional permanency of folding to a sheet, and an apparatus therefor, which is suitable for manufacturing frame bodies, cushioning members and other block products for packaging, from a sheet of paper and other recyclable materials. The method includes a step of moving respective folding working tools, disposed on one or both surfaces of a sheet, required amounts so as to fold the sheet along respective folding ruled lines, and a step of shortening spacings between the respective folding working tools in a uniform ratio in accordance with an apparent amount of shortening in a longitudinal dimension caused by the shifting, while synchronizing with the moving step. Directional permanency of folding can be accurately imparted to the sheet along the folding ruled lines.

Abstract: The present invention discloses folded corrugated material for producing segments or strips for use as Easter grass, packing material and the like or for use as flower pot covers, floral wrappings and ribbon materials.

Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient so that it is capable of inward deflection in the vicinity of the corrugating nip in order to cushion impact as the rolls interengage along the corrugating nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise levels, roll wear and improves the quality and consistency of corrugation.

Abstract: The present invention relates to a corrugator and corrugated fiberboard sheet manufacturing method which are capable of accurately adjusting the quantity of moisture included in a sheet to certainly suppress the warp deformation of the sheet with the passage of time. The corrugator has an adhering section equipped with a plurality of pressurizing units separately disposed in series along a sheet conveying direction, where a front linerboard and a rear linerboard are adhered to each other to form a corrugated fiberboard sheet and the corrugated fiberboard sheet formed in the adhering section is processed into a predetermined configuration in a processing section standing on the downstream side of the adhering section.

Abstract: A heating device (1) for a corrugated cardboard facility includes several heating plates (3) arranged sequentially along a path in the advancing direction of a sheet of corrugated cardboard (2). Compression elements (4) are arranged above the heating plates (3) in position to act on the sheet of corrugated cardboard (2) as it advances along the path. An intake belt (e) is located in a starting area (a) of the heating plates (3) between at least a part of the sheet of corrugated cardboard (2) and at least one compression element (4.1, 4.2).

Abstract: A method of forming a paper container uses a three ply corrugated material having at least one inner or outer sheet of paper that may be stretched or compressed circumferentially to permit subsequent rolling of the corrugated material about a mandrel. A flattening of the upper and lower edges of the corrugated material permit rolling and seaming operations to be used to assemble the bottom to the cup and to form a lip in the upper edge.

Abstract: An apparatus and related method for forming a double face paperboard web are disclosed. The apparatus of the present invention includes a heating section upstream from a drawing section. The heating section includes at least one heating plate having an upper surface facing a paperboard web and heated by a plurality of primary channels supplied with steam. A plurality of secondary channels extend through the heating plate intermediate the primary channels and a lower surface of the plate. A plurality of outlet ports communicate with each secondary channel and the upper surface of the heating plate. Steam supplied to the secondary channels exits through the outlet ports thereby producing a steam film between the upper surface of the heating plate and the lower surface of the paperboard web. The steam film substantially reduces frictional forces opposing movement of the web while also dramatically increasing the heat transfer to the paperboard web and accelerating the gelatinization of the glue therein.

Abstract: A system for pleating a continuous strip of foldable material including feeding the strip of foldable material between adjacent flights of cooperatively positioned endless conveyors having pleat folding arms pivotally associated therewith which are alternatively and interfittingly positioned to pleat the strip of foldable material as it movingly passes from one end of adjacent flights to the other end thereof.

Abstract: This invention relates to a double facer of a corrugating machine which aims to improve a drying state or bonding state between a single-faced corrugated fiberboard sheet and a liner and improve the quality of a corrugated fiberboard sheet. In a double facer for bonding together a single-faced corrugated fiberboard sheet and a liner to form a corrugated fiberboard sheet, provided are a heating member disposed along a conveying direction of the corrugated fiberboard sheet; a pressing unit, disposed so as to oppose the heating member, for pushing the corrugated fiberboard sheet against the heating member; a sheet conveying unit, disposed downstream the heating member, for conveying the corrugated fiberboard sheet; and a sheet feeding unit for feeding the corrugated fiberboard sheet toward the sheet conveying unit; while the pressing unit comprises a plurality of pressing devices disposed in series as being separated from each other along the conveying direction of the corrugated fiberboard sheet.

Abstract: The present invention relates of a method and apparatus for making an improved resilient packing material by forming, resiliently folding and crimping shredded strips of moistened paper material into an improved interlocking, bulk, packaging material. The method and apparatus includes a wetting or dampening system which can be selectively varied to regulate the moisture content of moistened paper material.

Abstract: This invention relates to a product packaging material and method, and in particular to a product packaging material (27) formed from a length of rolled corrugated paper (20) and a method of manufacture therefor. There is provided a packaging material comprising corrugated paper (20), the corrugated paper including non-sinusoidal corrugations (16, 18, 72). There is also provided a method of making a packaging material of multi-layer corrugated paper (27) including the steps of forming corrugated paper (20) having a sheet with sinusoidal corrugations (42), and compressing the sheet to destroy the sinusoidal form of at least some of the corrugations.

Abstract: A bin formed with a general circular shape in plan being formed from an outside liner of paperboard and an inner paperboard flute providing medium which is affixed to the outside liner. The flutes of the flute providing medium are larger than those of "A" flute. A removable sleeve interior, an optional base and lid are provided together with methods of carriage using same.

Abstract: A method and apparatus is disclosed for constructing block-shaped units of corrugated sheet material that are easily banded because of the absence of any irregularities in the units, and the units are as close to being cube-shaped as is possible for a given set of parameters. The automated stacking system comprises a computer programmed to determine a set of solutions to optimize a unit by determining an optimal number of corrugated sheets per bundle, and an optimal number of bundles per tier, and an optimal number of tiers per unit based upon customer order parameters. The system is initially set up with machine parameters defining machine constraints and a set of algorithm parameters which comprise desirability weighting factors. The desirability weighting factors allow a customer to customize the system according to preferred operating criteria.

Abstract: The labyrinth path in the corrugating nip of a single facer is substantially reduced by utilizing a small diameter intermediate corrugating roll captured between a pair of larger diameter conventional corrugating rolls. The two large diameter rolls capture the smaller roll and prevent bending thereof under corrugating loads. The corrugator may be operated at high speeds without the adverse increase in labyrinth path and web tension characteristic of large diameter corrugating rolls.

Abstract: A single facer has corrugating rolls of which the cross-sectional tip and root curves are elliptical (as broadly defined) to form a medium compression zone 38 beyond which, on each side of the tip center line, the root extends to define a clearance gap greater than the thickness of the medium; the root curve may (FIGS. 2 and 3) continue as an ellipse which also defines the flute flank, or alternatively the flute flank may be defined by a straight line 76 (FIG. 4) with a transition curve 58 between the straight line and the root curve 52. According to a different aspect of this invention, flank clearance is provided by the use of differently shaped flutes on the two corrugating rolls; for example (FIG. 5) the second roll 71 which carries the medium after corrugating may have straight flanks 76, and the other roll may have concave flanks 78.

Abstract: A method and a device for producing corrugated strip packaging parts to be used for packaging cylindrical or elongated parts in separate compartments. The device includes a series of form bodies arranged on an endlessly rotating belt. The form bodies have essentially the same inside cross-section as the lower loops of the corrugated strip material formed by the device and are joined together at their base flanks by elastic material areas. The belt is guided over rerouting points that temporarily spread apart two adjacent form bodies to form an enlarged intermediate space. A form tool is arranged adjacent one of the rerouting points to engage and press the material of the packaging part into the enlarged intermediate space.

Abstract: The invention is a method of fluting corrugating medium which can be formed in conventional or unconventional flute configurations. The method employs at least one additional corrugating roll in addition to the usual two. The first pair of rolls create initial flutes in the medium. Initially fluted medium is then transferred to a third roll of lesser flute pitch than the first rolls. In this manner the initially created flutes can be reformed into configurations not possible using conventional systems. A fourth roll can be used to achieve additional flute pitch reduction. Using this method flutes with very sharply angled tips can be formed. Other embodiments enable formation of less conventional cross sectional configurations such as flutes with asymmetric patterns.

Abstract: A method of producing a packing product includes the steps of feeding at least one sheet of material in a first direction; cutting the at least one sheet of material into a plurality of strips; the cutting being performed by rotating two sets of alternating, overlapping cutting discs; the feeding of the at least one sheet of material being between the two sets of cutting discs; advancing each of the strips by the rotating of at least an outer surface of a corresponding one of the cutting discs as the outer surface moves in the first direction; restricting each strip from continued advancing in the first direction; and sequentially folding each of the strip means by the restricting in opposition to the advancing. There is included apparatus and means for producing the packing product.

Abstract: For the corrugated deformation of a flat sheet of material, an upper row (2) of shaping tools (4) is pressed against a lower row (3) of shaping tools (5). The shaping tools of both the rows are, with that, also simultaneously pushed together so that they trace the shortening of the sheet of material during the deformation. Thus, the situation is achieved where no relative displacement between the sheet of material and the facing sides (6, 6') of the shaping tools (4 and 5) takes place, also in the case of numerous corrugations of relatively great height. The lower row of shaping tools is arranged on a rotor, whilst the upper row is fixed at a working station within the area of rotation of the rotor.

Abstract: Disclosed is an apparatus for longitudinally pleating a moving lamina. The apparatus features a curved axis roll having a stationary axis circumscribed by a rotating sleeve with a plurality of circumferentially oriented grooves in the rotating sleeve. The pleats are produced by the intermeshing of the lamina with the grooves of the rotating sleeve. Preferably a complementary curved axis roll having lands which interdigitate with the grooves of the first roll is used in conjunction with the first curved axis roll.The apparatus preferably further comprises a third curved axis roll disposed upstream of the first curved axis roll to substantially equalize the paths of travel of any points on the moving lamina by compensating for differences in the paths of travel between the edges and centerline of the lamina.

Abstract: A rolled paper embossing dispenser in which the paper is embossed and from which the paper is simultaneously dispensed. The dispenser includes a nip formed by a first embossing roll and a second embossing roll, both rotatably mounted within a cabinet. The first embossing roll has a plurality of spaced-apart annular bands with each annular band including discrete, spaced-apart knuckle projections extending radially from the roll. The second embossing roll includes annular slots and annular extensions arranged in alternating relationship with each annular slot having sufficient width to receive the knuckle projections without contacting any portion thereof as paper is fed through the nip and embossed. A lever or crank is provided for a user to rotationally drive one of the embossing rolls, the other embossing roll rotating only in response to the paper being drawn through the nip such that rotational slippage of one roll with respect to the other will not result in breaking or tearing the web.

Abstract: A method and apparatus for starch adhesive bonding of paper, paperboard, and natural cellulosic-fiber materials, especially liner and fluted corrugating medium, into manufactured items, particularly corrugated board. The method includes applying an adhesive coating, comprising starch and water, to a first substrate (e.g. tips of flutes of a corrugated medium), contacting the applied coating with another substrate (e.g. liner) and while so positioned contacting an exterior surface of at least one of the substrates with an ultrasonic energy generating means so as to transmit the ultrasonic energy to the adhesive coating to increase coating adhesion to the substrates.

Abstract: A method and apparatus for folding a length of material includes forming first and second transverse folds at opposite ends of the material whereby the material defines first and second end parts and a central part. Longitudinal corrugations are formed in the first and second end parts in order to reduce a transverse dimension of the first and second end parts. A third transverse fold is formed in the central part in order to bring the first and second end parts into superposition. In the resulting folded material, edges of the first and second end parts are recessed inward from edges of the central part.

Abstract: A device for the manufacture of a hose package formed by folding of a hose of flexible material, where the hose package consists of folds adjoining one another and forming wall elements connected to one another. The elements are situated outside one another in relation to a central axis of the hose package. The device has a fixing element and upper and lower folding plates in the shape of polygons. Through a controlled sequence of movements the fixing element and folding plates form the folds situated outside one another, and thereby the hose package. The folding plates are placed adjacent to one another and in end regions form corners of the polygon. In respective corner regions the plates are spaced from one another to form an opening or gap through which a pressing member can travel to contact the folds of the hose package and smooth out any wrinkles.

Abstract: A roll (16) for a corrugated board manufacturing machine (10) comprises a shell (32) defining an inner suction chamber (56) permanently connected to a source of low pressure. A series of radial suction apertures (60) open onto the peripheral surface (58) of the shell. According to the invention, the roll comprises a series of axial ducts (80) provided in the body of the shell (32) in which permanently circulates a heat-carrying fluid for heating the shell.

Abstract: A unique and novel storage package and method and apparatus for making the same wherein differences in dimension between the outer receptacle and a package stored therein are compensated by a unique corrugated spacer to provide snug storage, such as in the packaging of cigarette packs.

Abstract: A ring-shaped corrugated filter element blank having radially alternate peak and valley folds is placed on a first mold having as many first concentric projections as the number of the peak folds of the ring-shaped blank and as many first concentric grooves as the number of the valley folds of the ring-shaped blank, with the peak folds fitted respectively over the first projections and the valley folds fitted respectively in the first grooves. Then, the ring-shaped blank is pressed between the first mold and a second mold, the second mold having second projections lying along concentric lines fitting respectively in the first grooves with the valley folds received therein, and second concentric grooves receiving respectively the first projections with the peak folds fitted thereover. The ring-shaped blank is heated while it is being pressed between the first and second molds, thereby forming a ring-shaped filter element. Thereafter, the ring-shaped filter element is cooled.

Abstract: Apparatus for forming and fabricating single-faced paperboard, the lower corrugating roll is provided with numerous circumferential grooves which are partially evacuated beneath a traveling overlayment of paper web for the purpose of holding the web tightly against the corrugated roll profile. These grooves are evacuated by groove evacuation tubes connected with one or more vacuum manifolds. Such evacuation tubes have flared, tubular distal ends to match the slotted socket of respective tube holders. Each holder also includes a spring loaded mandrel to secure each tube in its respective socket in such a manner as to permit rapid removal and replacement of such tubes.

Abstract: A method and apparatus for making axial-flow filters wherein a sectorial-shaped sheet of filter material having corrugations therein parallel to the curved ends thereof is made from a flat sheet of filter material, and thereafter the corrugated sheet is made into an annulus to obtain the final product. Initially, an edge portion of a flat sheet of filter material is attached to a sectorial-shaped mold, having a mold surface defined by curved ridges and valleys parallel to the curved ends of the mold, so that the sheet is slanted up away from the mold surface from the smaller curved end of the mold. Thereafter a set of curved forming blades is moved down toward the mold to engage the sheet and to fold it successively and consecutively across the ridges of the mold and beneath the edges of the blades into the valleys of the mold to corrugate the sheet.

Abstract: A method for making a corrugated thin metal strip wherein corrugations are linear and extend obliquely from one longitudinal marginal edge to the opposite longitudinal marginal edge of the strip. The invention involves passing the thin metal strip through corrugating rolls for impressing a series of single apex, V-shaped chevron corrugations into the surface of the metal strip. The rolling of the strip between the helical gears is done in such a way that the apex of the V-shaped chevron is the last portion to leave the corrugating rolls whereby the apex is in tension and enables metal strip to be split into two obliquely corrugated metal strips along the apices of the chevron.

Abstract: A method and apparatus for starch adhesive bonding of paper, paperboard, and natural cellulosic-fiber materials, especially liner and fluted corrugating medium, into manufactured items, particularly corrugated board. The method includes applying an adhesive coating, comprising starch and water, to a first substrate (e.g. tips of flutes of a corrugated medium), contacting the applied coating with another substrate (e.g. liner) and while so positioned contacting an exterior surface of at least one of the substrates with an ultrasonic energy generating means so as to transmit ultrasonic energy to the adhesive coating to increase coating adhesion to the substrates.

Abstract: An apparatus performing a filter from a material for a filter element automatically and quickly. The filter made by the present apparatus has a plurality of wavy portions which are provided in such a manner that a plurality of wavy portions forms a circle.The apparatus employs a contracting apparatus for contracting a continuously corrugated strip of material for a filter element in such a manner that a distance between adjacent ridges of the corrugated strip is reduced so that the corrugated strip becomes the wavy portion of the filter. The apparatus also employs a rounding apparatus for rounding the continuously corrugated strip in such a manner that both ends of the strip are connected to each other so that the wavy portions made from the corrugated strip form a circle. The apparatus further employs a shaping apparatus for shaping the rounded continuously corrugated strip so that the rounded strip becomes the filter.

Abstract: A web of foam material is fed to a cutting station by upper and lower rollers drawing the web from a supply roll and along a low-friction table surface. A cutter station has a knife bar and blade, with a clamp bar coupled with the knife bar. The lower draw roller has its axle mounted in a pair of pivoted arms depressible by presser feet on a presser foot bar carried by the knife bar. When a desired length of web has been drawn past the cutter station, actuation of the knife bar lowers the blade toward a grooved anvil, while the presser feet swing the arms down to depress the lower roller away from the web to stop drawing it. Immediately after interrupting drawing action, the web is clamped by the clamp bar, and then immediately thereafter cutting occurs. The table has bridge-like fingers extending downstream through grooves in the movable lower feed roller. These fingers support the web when the lower roller is swung down.

Abstract: A method is set forth for forming a unitary structure having a plurality of deformable foils having first and second sides stacked one upon another with the first sides facing in one direction and the second sides in an opposite direction, each of the foils having an undulating cross-section, adjacent of the foils having their undulations orthogonal to one another and every other one of the foils having parallel orientations. The method comprises positioning a first plurality of parallel rods against the first side of a respective one of the foils and positioning a second plurality of parallel rods against the second side of the same foil with the rods of the second plurality of rods between and parallel to the rods of the first plurality of rods. Thereafter the aforementioned steps are repeated with each next adjacent foil having the rods defining the undulating cross-section thereof at a non-zero angle to the rods of the next adjacent foil.

Abstract: A method and apparatus for making axial-flow filters wherein a sectorial-shaped sheet of filter material having corrugations therein parallel to the curved ends thereof is made from a flat sheet of filter material in the first step, and thereafter the corrugated sheet is made into an annulus to obtain the final product. In the first step, an edge portion of a flat sheet of filter material is attached to a sectorial-shaped mold, having a mold surface defined by curved ridges and valleys parallel to the curved ends of the mold, so that the sheet is slanted up away from the mold surface from the smaller curved end of the mold. Thereafter a set of curved forming blades is moved down toward the mold to engage the sheet and to fold it successively and consecutively across the ridges of the mold and beneath the edges of the blades into the valleys of the mold to corrugate the sheet.

Abstract: A one-sided corrugated cardboard machine comprising a machine stand with two fluted rollers in meshing engagement with each other and an auxiliary roller rotatably supported therein, the axes of said rollers being disposed approximately in a common plane preferably inclined towards the vertical, with the machine stand being supported at the underground on one side of the plane, and members cooperating with the roller pack such as deviation rollers, guide plates, scrapers for the pressure roller, and the like, being supported in a stand section on the other side of the plane, said section being a rigid frame spanning the roller pack and which is detachably yet fixedly connectible to the machine stand.

Abstract: A one-sided corrugated cardboard machine comprising a machine stand, an upper and a lower fluted roller as well as a pressure roller cooperating with the lower fluted roller and pivotally supported on lever arms at the machine stand, adjustable abutment surfaces at the machine stand associated with the lever arms, and an adjusting mechanism supported at the machine stand and cooperating with the lever arms which to adjust the pressure roller nip urge the lever arms against the abutments, with the abutment surface arranged to face the pressure roller nip and limiting the movement of the lever arms away from the pressure roller nip.

Abstract: A single facer including a main frame installed on a base for supporting a paste application roll, a pressure roll and so on, a movable frame fixed on or removably supported on the main frame for rotatably supporting upper and lower corrugated rolls in meshing engagement with each other, and a transfer mechanism for moving the movable frame in a transverse direction substantially in the axial direction of the respective upper and lower rolls to transfer them out of or into the main frame.