EP0949064A2 - Assembly of pressure plates for joining sheets of material, each comprising at least one flat sheet and/or at least one corrugated sheet and a corrugated sheet - Google Patents

Abstract

The joining of several smooth and corrugated strips into a corrugated cardboard strip (P), with glue being applied to one of the strips, is carried out by a pressure unit (14). This unit is fitted with a pressure plate (22) and a heated counter pressure plate (26). The strips of material to be joined are passed between the two plates. The pressure unit, with its pressure plate, can be brought towards or away from the counter pressure plate. The pressure plate can also be heated.

Description

The present invention relates to an arrangement of pressure plates to join a plurality of strips of material, each comprising at at least one smooth strip or / and at least one wavy strip, in strip of corrugated board, glue being applied to at least sections of at least at least one strip of material, the arrangement comprising a unit of pressure fitted with pressure plate and back pressure plate heatable, between which the strips of material to be joined are passed, the pressure unit with its pressure plate being reconcilable respectively removable from the back pressure plate.

Such arrangements of pressure plates are known in the art anterior. Such an arrangement is for example described on page 10 of the print "The Double-Facer Group", no. of print 2 (694GB) 0.5 of Peters Maschinenfabrik GmbH. In this arrangement, the strips of material provided with glue are supported on the plate heatable back pressure and are pressed against each other on the side opposed by pressure plates. The heat supplied by the plate heatable back pressure accelerates the hardening of the adhesive. On the other hand, with multi-layer corrugated cardboard strips, i.e. strips of corrugated cardboard with two or more corrugated strips (for example double-sided corrugated board), the result is that the temperature in corrugated cardboard decreases with distance from back pressure plate heated, so that a complete drying of the bonding places away from the back pressure plate lasts longer. To hold account of this problem it is necessary, with strips of material in movement, correspondingly decrease the speed of movement, to allow a sufficiently long heat treatment of the places of bonding, or it is necessary to size the back pressure plate heatable with a corresponding length, or it is necessary, increase the amount of heat supplied per unit of time so corresponding. In addition, the expenses of the necessary heat treatment go up with the thickness of the corrugated cardboard and / or with the grammage (weight by surface of the corrugated board). Of course the reduction in the speed of movement of the material web as well as the extension of the arrangement as well as the increase in the amount of heat supplied by the plate back pressure per unit of time are limited economically and convenient.

This is why the object of the present invention is to provide an arrangement pressure plates of the generic type, which accelerates the hardening of the glue while maintaining the same speed of movement, the same length of the arrangement and the same supply of heat by the back pressure plate.

In an arrangement of generic type pressure plates, this object is accomplished in that the pressure plate is also formed so heatable.

By heating the back pressure plate as well as the pressure, heat can be brought to the corrugated board on both sides, so that on the one hand the total heat supply can be increased by maintaining the same heat supply rate through the back pressure plate, and on the other hand a uniform temperature profile can be obtained throughout the thickness of the corrugated cardboard. So, first the gelation and then the hardening of the glue are made more uniform throughout of the thickness of the corrugated cardboard. Therefore, there is no longer a delay of hardening as a function of the rising distance from the back pressure plate. Because of the more uniform hardening throughout the thickness corrugated cardboard, the duration of treatment required for curing can be reduced using the arrangement of pressure plates according to the invention. Consequently, this results in less passage times long during the production of corrugated board respectively a smaller minimum required length of pressure plate arrangement, if the strip of corrugated cardboard is moving. This also applies to large thicknesses of corrugated cardboard and / or large grammages.

The heatability of the pressure plate can be obtained in the following ways: different. For example, heating wires for heating resistive pressure plate can be provided in or at the pressure plate pressure. However, preferably it is expected that a cover plate is arranged with the pressure plate on its side turned away from the plate back pressure, the cover plate and the surrounding pressure plate a cavity which can be supplied with a heat transfer fluid. This will heat the pressure plate using simple means, which are usually anyway available at the place of operation because of the heating similar to the back pressure plate. Therefore, we can also consider retrofitting existing facilities. As heat transfer fluid we can provide various substances such as oils heat transfer hydraulics. However, preferably water vapor is used as a heat transfer fluid because of its availability expensive, its non-pollution etc.

Pressure plate and cover plate can be made various materials, for example depending on the heat transfer fluid used. It is possible to make them from synthetic material or plates covered with synthetic material. However, preferably it is expected that the pressure plate or / and the cover plate is respectively are made of metal, preferably anti-rust steel. This ensures a particularly robust arrangement with easy maintenance and good thermal conduction characteristics.

To ensure uniform application of pressure on the cardboard strip corrugated plane by the pressure plate, it is expected that the wall thickness pressure plate is between about 3 mm and about 5 mm, from preferably about 4 mm. Since the cover plate is not exposed to such large mechanical loads, its wall thickness may be considerably smaller, and preferably it is expected, that the wall thickness of the cover plate is between 0.5 mm and approximately 2 mm, preferably about 1.5 mm. In addition, such thicknesses of wall allow relatively "rapid reaction" thermal control of the pressure plate to be heated, because the volumes to be heated can stay limited.

For charging a heat transfer fluid into the cavity enclosed between the pressure plate and cover plate, it is expected, that the cavity can be connected to at least one fluid supply line and at least one fluid outlet line. This allows integration of the fluid system of the heatable pressure plate in a superior fluid system, so that the heat transfer fluid can flow through the supply line fluid, the cavity enclosed between the pressure plate and the cover, and the fluid outlet line. In view of a movement of the pressure unit with its pressure plate relative to the pressure plate back pressure, fluid supply lines and output lines fluid are advantageously formed in a flexible manner.

To allow easy connection of the fluid supply lines and from the fluid outlet lines to the pressure unit, it is intended that at least two pipes used for connection to the fluid lines are arranged on the cover plate. In case of a cover plate metal, these pipes can be welded directly to it. The if necessary, it is also possible to provide relief valves overpressure or other pneumatic or hydraulic elements to the plate cover.

To form the cavity between the pressure plate and the cover plate, it is expected that the cover plate is sealed, preferably at its outer contour, to the pressure plate. This waterproof junction can be completed by gluing or, in the preferred case a metal pressure plate and a cover plate metallic, by welding, the last possibility representing a junction particularly robust and reliable seal between the pressure plate and the cover plate.

As a measure to increase the stability and rigidity of the plate pressure heatable it is expected that the cover plate is attached to the pressure plate at a plurality of points, which are preferably uniformly distributed, the cavity between these junction points having the shape of a vault. Such a junction from the pressure plate to the plate moreover allows a particularly easy manufacture of the cavity as will be described below. Namely, it is possible to ask an essentially flat cover plate on the pressure plate also essentially flat, attach the cover plate to the level of its contour outside the pressure plate in a leaktight manner and to provide in addition individual junction points in the area to inside the outside outline. In case of a metal pressure plate and a metal cover plate, the junction is preferably made by welding or spot welding. After such a junction, a fluid hydraulic, preferably water, is pressed under high pressure between the pressure plate and the adjacent cover plate by pipes supply lines and suitable outlet lines, such as tubing already described. Because of the wall thickness of the plate lower coverage compared to pressure plate, high pressure of hydraulic fluid leads to plastic deformations of the plate bump-like cover, so that a continuous cavity in shape a vault is formed. Proper support of the pressure plate avoids, that this one also deforms in a plastic way. Then we can remove hydraulic fluid from the cavity and move on to further machining the pressure plate.

In general, the positioning of the material strips between the plate pressure and the back pressure plate is done or by a movement discontinuous or preferably by continuous movement of the strips of matter. To prevent the movement of the corrugated cardboard strip from being affected by joints of the material strip, called connections, it is provided, that the pressure plate is equipped with a guide face on the side of the material web feed and, if desired, also on the side of the material web outlet. This allows the joint to enter freely under the pressure plate and to flow under it and prevents jams caused by sections of the web of material returned in the joint area (connection area).

In addition, to allow variable positioning of the plate pressure, it is provided according to the invention, that the pressure unit comprises a support of the pressure plate and an operating device for move the pressure plate closer to the back pressure plate respectively to move the pressure plate away from the back pressure plate. For uniform application of pressure on corrugated board using the support of the pressure plate, it is provided according to the invention, that the support of the pressure plate comprises at least one bar of support, which is attached to the pressure plate, preferably by through the cover plate. This measurement allows mounting sufficiently stable from the pressure plate to the support of the pressure plate pressure.

Preferably the at least one support strip has a plurality protrusions, which are attached to the cover plate at a share of the points from the junction to the pressure plate. It is particularly advantageous to provide projections on the support bar, if the cavity enclosed between the pressure plate and the cover plate is shaped like an arch because of its manufacture by hydraulic expansion, as described above. In this case it is possible to limit the places of junction between the support bar and pressure plate respectively the plate coverage at or at a part of the junction points, so that the shape of the vault-shaped cavity is not changed when mounting the support strip.

With such a junction of the pressure plate to the support strip by through projections attached to the junction points it is particularly advantageous, if there is no other mechanical contact between the support strip and the cover plate except through the protrusions. In other words, it is provided according to the invention, that the at least one support strip is arranged between its junction projections with a gap of the cover plate. This avoids thermal contact between the plate cover and the support strip, through which heat can be dissipated. Thus the gap serves as insulation between the support strip and the cover plate.

As an alternative to a junction between the pressure plate and the bar support using a plurality of protrusions, it is expected that bolts threaded are fixed, essentially perpendicular to the plate pressure, to the cover plate, preferably at part of the points of connection to the pressure plate, by which the at least one strip of support is fixed, i.e. screwed, directly or by means of minus an intermediate bar, to the pressure plate. Such a junction between the pressure plate respectively the cover plate and the support bar using threaded bolts is particularly easy to mount, so that the pressure plate can easily be moved away from the support bar or be mounted to it, in particular for a repair and / or replacement.

For easy movement of the pressure plate relative to the back pressure plate, it is provided according to the invention, that the device operation includes an arrangement of levers articulated to a frame as well that an operating drive member attached to the lever arrangement and preferably comprising at least one cylinder / piston arrangement actuable using a fluid. The drive trainer can be actuated hydraulically or pneumatically. Such a device is insensitive to its operating environment and ensures high security requiring little maintenance.

Because of the diversity of corrugated products, for example the thickness of the corrugated cardboard to be manufactured or the shape of the corrugated strip respectively the corrugated strips enclosed in it, it is desirable that all products can be produced with a single arrangement of pressure plates. For this purpose it is advantageous that the position of the pressure plate relative to the back pressure plate as well as the pressure are variable. To achieve this goal with simple means, according to the invention, it is provided that the operating force of the member maneuvering training is variable, preferably without gradations. In addition, it is preferably provided in this context, that the arrangement of levers is articulated to the at least one support bar. By such articulated junction, it is possible to obtain a uniform pressure application on the entire contact surface between the strip of corrugated cardboard and the plate pressure independent of the variations of the position respectively of the operating force of the operating drive member.

In addition, the invention relates to a device for joining a plurality of strips of material, comprising a plurality of arrangements of sheet plates pressure as described above. According to the invention, the arrangements pressure plates in such a device are arranged in the form of matrix in the direction of advancement of the strips of material or / and transverse to this direction of advance, one adjacent to the other. A matrix arrangement in the direction of advancement and transverse to it of several arrangements of heatable pressure plates according to the invention therefore allows a treatment of the strip of corrugated cardboard on a large area and on both sides and, as required, variable with spatial resolution in pressure and heat supply. this is advantageous in view of a large production capacity.

To ensure an advantageous operation of the device according to the invention also from an economic point of view, it is expected that at least some of the pressure plate arrangements is heatable using a common heating arrangement, preferably being chargeable with heat transfer fluid in common. This means that several arrangements of pressure plates are respectively associated with an arrangement of upper heating and powered by it. In the event of an arrangement of heating with a system that transports heat transfer fluid, the fluid coolant can flow through the individual arrangements of plates of pressure in different orders determined by certain "couplings". Through example, it is provided as an alternative according to the invention, that the fluid coolant flows successively through the plate arrangements of pressure associated with a common (upper) heating arrangement (coupling in series). So the temperature drops in the direction of flow, because the heat transfer fluid gives off heat with each arrangement of pressure plates crossed and its surroundings along its path of flow.

As another coupling alternative, the heat transfer fluid can flow through the pressure plate arrangements associated with a common heating arrangement in parallel (parallel coupling).

With such an arrangement, each arrangement of pressure plates is crossed by fluid of the same temperature, so these arrangements also have essentially the same temperature.

According to the above, different heat supply profiles can be fitted into an arrangement of pressure plates in the form of matrix using different couplings (coupling in series, coupling in parallel), so that it is for example possible to adjust a temperature higher in the area of the edges parallel to the direction of travel than in the central area. This is advantageous, because when drying the moisture glue is removed, which must be dissipated along the ribs wavy bands, so that the relative humidity is greater in the edge area only in the central area. However, gradients of forward direction temperature as well as gradients of surface temperature are also possible. In addition, it is possible to do not heat individual pressure plates of the arrangement matrix respectively not to charge them with the heat transfer fluid. The different coupling arrangements therefore allow adaptation direct pressure plate arrangements to the carton product corrugated to manufacture, for example according to the number of strips wavy, the grammage used etc.

Individual pressure plates can be operated relative to to the back pressure plate using operating devices individual or, in case of mutual mechanical coupling, using organs maneuvering training associated with several pressure plates.

Fig. 1

montre une vue de côté d'une section du côté de l'entrée de la bande de matière d'un dispositif pour joindre une pluralité de bandes de matière selon l'invention;

Fig. 2

montre une vue en détail d'une unité de pression avec son organe d'entraínement de manoeuvre à la Fig. 1;

Fig. 3

montre une vue en coupe du arrangement selon l'invention selon la ligne III-III à la Fig. 1;

Fig. 4

montre une vue détaillée en perspective d'une plaque de pression et d'une plaque de couverture avec des tubulures;

Fig. 5

montre une vue en coupe de la plaque de pression selon l'invention selon la ligne V-V à la Fig. 4;

Fig. 6

montre des vues détaillées de la zone autour d'un point de jonction correspondant à la partie VI à la Fig. 2,

Fig. 6a

montrant une jonction entre la barrette de support et la plaque de pression par l'intermédiaire d'une saillie et

Fig. 6b

montrant une jonction entre la plaque de pression et la barrette de support par l'intermédiaire d'un boulon fileté; et

Fig. 7

montre des représentations schématiques différentes des couplages à l'intérieur d'une matrice de plaques de pression,

Fig. 7a

montrant un couplage en série traversé en direction d'avancement et

Fig. 7b

montrant un couplage en série symétrique traversé transversalement à la direction d'avancement.

In what follows, the invention will be illustrated more precisely with the aid of a few exemplary embodiments referring to the appended drawings.

Fig. 1

shows a side view of a section on the entry side of the strip of material of a device for joining a plurality of strips of material according to the invention;

Fig. 2

shows a detailed view of a pressure unit with its operating drive member in FIG. 1;

Fig. 3

shows a sectional view of the arrangement according to the invention according to line III-III in FIG. 1;

Fig. 4

shows a detailed perspective view of a pressure plate and a cover plate with pipes;

Fig. 5

shows a sectional view of the pressure plate according to the invention along the line VV in FIG. 4;

Fig. 6

shows detailed views of the area around a junction point corresponding to Part VI in Fig. 2,

Fig. 6a

showing a junction between the support bar and the pressure plate by means of a projection and

Fig. 6b

showing a junction between the pressure plate and the support bar via a threaded bolt; and

Fig. 7

shows different schematic representations of the couplings inside a matrix of pressure plates,

Fig. 7a

showing a coupling in series crossed in the direction of advancement and

Fig. 7b

showing a symmetrical series coupling crossed transversely to the direction of advance.

Fig. 1 shows a device according to the invention generally designated by 10 for join a plurality of strips of materials 12a, 12b, 12c and 12d in cardboard corrugated. The strips 12a, 12b, 12c are composite strips formed each by a smooth strip and a wavy strip, while the 12d strip is just a smooth band. The device comprises a plurality of pressure 14, each being mounted to a frame 16 by means of a operating drive member 18 as well as support pins 20. A pressure plate 22 is mounted on the underside of the pressure 14 by means of support bars 24. Below the pressure plate 22 is mounted a back pressure plate 26 fixed to the frame 16, extending essentially in the horizontal direction and forming an essentially parallel pressure plate arrangement with the pressure plate 22 of the pressure unit 14.

The pressure plate 22 and the back pressure plate 26 are each heatable arrangement, the heatable arrangement of the plate back pressure 26 not being described in more detail below. To note only that the backpressure plate 26 is heated preferably by a heat transfer fluid system. In this example of embodiment, the pressure plate 22 is also heatable by a system carrying heat transfer fluid. For this purpose, the plate of pressure 22 is charged with heat-transfer fluid by supply lines and upper outlet 28 and 30 via fluid lines flexible 32.

During the operation, the strips of material 12a - 12d, at least of which sections near the undulating peaks were covered with glue, preferably immediately before entry on the entry side of the device 10, are guided by guide rollers 34 respectively guide elements 36 to a joining roller 38, where their sections with glue pressed against each other. At that time, the sticks to the contact points between the individual strips 12a - 12d is always liquid respectively wet, so that mutual adhesion bands is relatively small immediately behind the roll of junction 38, seen in a direction of advance A. To obtain cardboard corrugated, of which the individual strips of material 12a - 12d forming this carton have a sufficiently strong mutual adhesion it is necessary apply pressure to the corrugated board in the device section 10 along the joining roller 38 in the direction of advancement A and bring at the same time heat to accelerate gelation and next hardening with glue. This is done through the cooperation of the units pressure 14 with pressure plates 22 and back pressure plate 26. It will be noted that preferably the first three units of pressure 14, 14 ', 14' 'along the junction roll 38 towards advancement A are arranged in a heatable manner, because the both gelled respectively hardened after the third 14 '' pressure unit, that the subsequent heat supply on both sides by the pressure unit heatable 14 and the heatable backpressure plate 26 is no longer necessary. However, depending on the desired speed of movement of the corrugated board and the type of corrugated board product to be produced, plus or fewer pressure units 14 can be arranged in a heatable manner in the direction of advancement A.

Fig. 2 shows a detailed view of a pressure unit 14 according to the view in Fig. 1. The components already shown in Fig. 1 have the same references in FIG. 2. The pressure unit 14 is pivotally mounted to the support axis 20 by a support arm 40. Near the housing pivotable on the support axis 20, an operating lever 42 is fixed to the support arm 40 in orientation essentially perpendicular to the arm support 40. The actuating drive member 18 arranged as hydraulic force element is articulated to the operating lever 42 by through a hydraulic piston 44, a hydraulic cylinder 46 receiving the hydraulic piston 44 being articulated to the frame 16.

At the end of the support arm 40 remote from the axis of the support, a junction articulated to the terminal strip 24 is provided near the center of gravity S of it. Because of this measurement, the terminal strip 24 is always in an essentially horizontal position when moving of the support arm 40 around the support axis 20.

On the side of the terminal strip 24, which is remote from the support arm 40, the pressure plate 22 is mounted, the construction and connection of which to the terminal strip 24 are illustrated in the enlarged part VI. In the following description of Figs. 6a and 6b, we refer in more detail to this enlarged part. However it will be noted here, that the plate of pressure 22 is mounted on the terminal strip 24 in such a way that its center of gravity lies in a plane essentially perpendicular to the direction of travel A, in which plane the center of gravity is S of the junction strip 24 as well as the axis of rotation of the junction articulated between the support arm 40 and the junction strip 24.

A cover plate 48 is mounted on the upper face of the plate pressure 22 in such a way that it encloses an arch-shaped cavity 50 with the pressure plate 22. This cavity is accessible by pipes 52 and 52 ', which are connected to the upper supply line 28 and the upper outlet pipe 30 for the supply and exit, respectively, of heat transfer fluid by flexible fluid lines 32.32 '. At the end of the inlet side and the outlet side of the plate pressure 22 relative to the direction of advance A, of the guide faces 54 are provided, which allow the free entry of corrugated cardboard into the space between the pressure plate 22 and the back pressure plate 26 and its sliding in this space.

It will also be noted that an adjustment arrangement 56 is provided for at the articulated junction between the support arm 40 and the junction strip 24 allowing the resistance of the joint to be varied.

During the actuation of the actuating drive member 18 arranged as a hydraulic force element, the pressure plate 22 can be pivoted about the support axis 20 from the mutual contact position of pressure plate 22, corrugated cardboard P and back pressure plate 26 shown in FIG. 2 in a position removed from the carton corrugated P respectively of the back pressure plate 26 by the retraction of the hydraulic piston 44 in the hydraulic cylinder 46 and the associated pivoting of the operating lever 42 as well as of the support arm 40 connected with it. In addition it is possible to apply pressure to corrugated cardboard P using pressure plate 22 by moving opposite the hydraulic piston 44 out of the hydraulic cylinder 46 with opposite pivoting around the support axis 20. The pressure unit 14 thus allows positioning without gradations of the pressure plate 22 compared to the back pressure plate 26 and therefore a variation without gradations of pressure force and pressure applied to the cardboard wavy P.

Fig. 3 shows a sectional view along line III-III in FIG. 1. Identical components have the same references as in Figs. 1 and 2. It is evident from FIG. 3, that four pressure units 14 ₁ , 14 ₂ , 14 ₃ , 14 ₄ are arranged on the support axis 20 one next to the other, an operating drive member 18 being respectively provided on the two axial ends of the axis of rotation 20 for the synchronous pivoting movement of the pressure units 14 ₁ , 14 ₂ , 14 ₃ , 14 ₄ around the support axis 20. In addition we recognize the fluid supply line upper 28 supplying the four pressure units 14 ₁ - 14 ₄ with heat transfer fluid and being formed transverse to the direction of advance A oriented in the plane of FIG. 3. The supply line 28 passing transversely to the direction of advance A is itself connected to the supply lines 58, 58 ′ for the supply and for the outlet of heat transfer fluid.

Fig. 4 shows a detailed perspective view of a pressure plate 22 provided with a cover plate 48. For orientation reasons, the direction of travel A is shown, in which a strip of corrugated cardboard spreads. At the end of the entry side as well as at the end of the side of the outlet of the pressure plate 22 are provided the faces of guide 54 showing upwards.

Throughout the contour of the edges 60 of the cover plate 48, the cover plate 48 and pressure plate 22 are welded so waterproof. In the region inside the contour of the edges 60 of the plate cover 48, this and the pressure plate 22 are additionally joined by welding points 62. The cover plate 48 is lifted from the pressure plate 22 in the shape of an arch by an appropriate method of manufacturing, for example by the hydraulic expansion described above.

This is also visible in Fig. 5 showing a section along line V-V in Fig. 4. Thus the vault-shaped cavity 50 is formed between the plate of pressure 22 and the cover plate attached thereto. When entering heat transfer fluid in tubing 52 welded to the cover plate 48 and the outlet of the fluid through the tubing 52 'disposed on the plate cover diagonally to the tubing 52, this cavity is crossed by the heat transfer fluid according to the arrows punctuated in FIG. 4.

Fig. 6 shows two detailed views of alternative joining possibilities (Fig. 6a and 6b) of the pressure plate 22 and the terminal strip 24 corresponding to part VI in FIG. 2, the corrugated board having three wavy bands shown in Part VI being removed in Fig. 6.

Corresponding to a first alternative according to the invention at the junction of the pressure plate 22 and the junction strip 24, we see in FIG. 6a a section of the junction strip 24 with several projections 64 on its face lower (of which only one shown in Fig. 6a), the projections corresponding to the arrangement on the one hand of the junction points 62 between the pressure plate 22 and cover plate 48. As illustrated in the Fig. 6a, the terminal strip 24 is joined to the cover plate 48 and by the latter to the pressure plate 22 by the projection 64 at a welding point 62. In any case the height h, by which the projection 64 projects from the face 66 of the terminal strip 24 is larger than the maximum bulge w of the cover plate 48, so that there has no place of mechanical contact and thus of thermal contact between the underside 66 of the terminal strip 24 and the cover plate 48 except on the undersides of the projections 64 in the area of the points of welding 62. This avoids that heat is dissipated from the fluid heat transfer to the terminal strip 24 by a thermal bridge between the face interior 66 of the terminal strip 24 and the cover plate 48 sealing the cavity 50 upwards, and this heat is therefore no longer available on the underside of the pressure plate 22 to accelerate the hardening of the glue in the corrugated cardboard.

In addition, Fig. 6a shows the thickness ratio between the thickness D of the pressure plate 22 and the thickness d of the cover plate 48. In view of manufacturing by the process of hydraulic expansion it is advantageous, that the thickness D of the pressure plate 22, as shown, amounts to at least twice the thickness d of the plate cover 48.

Fig. 6b shows a second alternative according to the invention of the junction pressure plate 22 and terminal strip 24, components identical bearing the same references as in FIG. 6a. In Fig. 6b, a threaded bolt 63 is welded to the cover plate 48 perpendicular to the pressure plate 22 at a welding point 62 on the side of the cover plate 48 showing towards the bar of junction 24. This threaded bolt 63 passes through a passage orifice 65 of a intermediate bar 67 resting on the crowns of the plate of cover 48. On the side of the intermediate bar 67 diverted from the cover plate 48, a hexagonal nut 69 is screwed on the section protruding from the threaded bolt 63, this nut pushing the intermediate bar 67 on the crowns of the cover plate 48. Means of stopping various screws, such as washers or lock washers, can be placed between hexagonal nut 69 and the intermediate bar 67, these means not being shown in FIG. 6b to allow a simple representation. On the side of the diverted intermediate bar 67 of the cover plate 48, the junction strip 24 is welded to the intermediate bar 67 by several projections 64 '(of which only one shown in Fig. 6b) with a certain distance from the passage orifice 65. However, it is also possible to connect the intermediate bar 67 and the terminal strip 24 in a manner not represented by elements separate couplings, for example by mutual screwing. In addition, it is also possible to prepare the terminal strip 24 directly for a screwed with threaded bolts 63, so that the intermediate bar 67 can be removed.

The alternative of a junction of the pressure plate 22 and the strip of junction 24 shown in FIG. 6b has the advantage that this junction is easy to do and to undo, so that the pressure plate 22 can be removed from the terminal strip 24 in a simple manner for reasons of assembly, troubleshooting and replacement. In addition, heat transfer is limited due to the relatively small total contact surface between the cover plate 48 and the intermediate bar 67.

Fig. 7 shows various possibilities of a passage through several heatable pressure plates 22 arranged in the form of a matrix, the matrix arrangement 68 with lines R ₁ - R ₅ transverse to the direction of advance A and columns S ₁ - S ₄ in the direction of advance A being shown schematically in top view. The arrows inside the matrix arrangement 68 represent the directions of the passage of the heat transfer fluid through the pressure plates 22. Pressure plates not crossed by arrows are not charged with heat transfer fluid.

Fig. 7a shows a matrix arrangement 68 composed of 20 pressure plates, the first three lines R ₁ , R ₂ , R ₃ passing transversely to the direction of advance being charged with heat-transfer fluid and the lines R ₄ , R ₅ remaining without heating . Considering for example the column S ₁ with this coupling, the heat transfer fluid enters the pressure plate 22 ₁ arranged in the first place on the inlet side and gives heat there to the section of the strip of corrugated cardboard located at the below. Then the fluid flows from the pressure plate 22 ₁ into the pressure plate 22 ₂ , the heat-transfer fluid already having given up part of its thermal energy and thus having a lower temperature than when it entered the pressure plate 22 ₁ . After having passed through the pressure plate 22 ₂ and having yielded more heat to the corrugated cardboard, the heat transfer fluid flows into the pressure plate 22 ₃ , the fluid having again a lower temperature when it passes through the plate pressure 22 _{3 only} when entering the pressure plate 22 ₂ . The pressure plates of columns S ₂ and S ₃ are passed like those of column S ₁ .

With the matrix arrangement according to FIG. 7a, a temperature gradient is thus obtained which decreases in the direction of advance A due to the generation of heat in the direction of flow of the fluid. Such coupling can be advantageous if the wet adhesive for bonding the strips of individual material to the strip of corrugated cardboard is to be returned from its liquid state to a state like a gel in the region of the first line R ₁ of the plate pressure, which requires a strong supply of heat. The gelled adhesive is then cured, which requires a lower heat supply as a function of the rising distance from the inlet side end of the die arrangement, because the degree of hardening rises as a function of the rising distance from the end of entry side.

Fig. 7b shows another coupling of the fluid system, to which heat transfer fluid has passed from the edge area (columns S ₁ , S ₄ ) of the matrix arrangement 68 transversely to the direction of advance A in the central area (columns S ₂ , S ₃ ) and left this zone. Corresponding to the above illustrations in FIG. 7a, the coupling arrangement according to FIG. 7b leads to a heat supply profile transverse to the direction of advance A, a high heat flow being brought to the edge areas (columns S ₁ , S ₄ ) of the corrugated cardboard and the heat supply decreasing towards the center (columns S ₂ , S ₃ ) of the matrix arrangement 68. Such a coupling arrangement may for example be advantageous, if during the manufacture of wide strips of corrugated cardboard the degree of humidity in the edge areas exceeds that of the central area, so that a greater supply of heat is necessary in the areas of the edges to expel moisture.

We can also consider combining the coupling arrangements previous according to Figs. 7a and 7b, or not to load plates of individual pressure of heat transfer fluid, while plates of neighboring pressures are charged with heat transfer fluid, to obtain certain temperature gradients and thus adapted heat supply profits the respective application (different thicknesses of corrugated cardboard, different grammages, different device speeds etc.) with resolution spatial.

Claims (23)

Arrangement of pressure plates for joining a plurality of strips of material (12a, 12b, 12c, 12d), each comprising at least one smooth strip (12d) or / and at least one corrugated strip (12a, 12b, 12c), corrugated cardboard strip (P), glue being applied to at least sections of at least one strip of material (12a-12d), the arrangement comprising a pressure unit (14) equipped with a pressure plate (22) and a heatable back pressure plate (26), between which the strips of material (12a-12d) to be joined are passed, l the pressure unit (14) with its pressure plate (22) being approximable respectively distant from the counter-pressure plate (26),
characterized in that the pressure plate (22) is also heatable. Arrangement of pressure plates according to claim 1,
characterized in that a cover plate (48) is arranged on the side of the pressure plate (22) diverted from the back pressure plate (26), the cover plate (48) and the pressure plate (22) surrounding a cavity (50) which can be supplied with a heat transfer fluid, preferably steam. Arrangement of pressure plates according to claim 2,
characterized in that the cavity (50) can be connected to at least one fluid supply line (28,32) and at least one fluid output line (30,32). Arrangement of pressure plates according to claim 3,
characterized in that at least two tubes (52.52 ') for connection to the fluid lines (32.32') are arranged. Arrangement of pressure plates according to any one of claims 2 - 4,
characterized in that the cover plate (48) is joined to the pressure plate (22) at a plurality of points (62), which are preferably distributed uniformly, the cavity (50) between these junction points (62) having the shape of a vault. Arrangement of pressure plates according to any one of Claims 2 to 5,
characterized in that the cover plate (48) is tightly joined, preferably at its outer contour (60), to the pressure plate (22). Arrangement of pressure plates according to any one of claims 2 - 6,
characterized in that the pressure plate (22) or / and the cover plate (48) are respectively made of metal, preferably of anti-rust steel. Arrangement of pressure plates according to any one of claims 2 - 7,
characterized in that the wall thickness (D) of the pressure plate (22) is between about 3 mm and about 5 mm, preferably about 4 mm. Arrangement of pressure plates according to any one of claims 2 - 8,
characterized in that the wall thickness (d) of the cover plate (48) is between about 0.5 mm and about 2 mm, preferably about 1.5 mm. Arrangement of pressure plates according to any one of Claims 1 to 9,
characterized in that the pressure plate (22) is equipped with a guide face (54) on the side of the material strip supply and, if desired, also on the side of the material strip outlet. Pressure plate arrangement according to any one of Claims 1 to 10,
characterized in that the pressure unit (14) has a pressure plate support (24,40) and an operating arrangement (18) for bringing the pressure plate (22) closer to the back pressure plate (26) respectively to distance the pressure plate (22) of the back pressure plate (26). Arrangement of pressure plates according to claim 11,
characterized in that the pressure plate support (24,40) has at least one support strip (24), which is joined to the pressure plate (22), preferably via the cover plate (48). Arrangement of pressure plates according to claim 12,
characterized in that the at least one support strip (24) has a plurality of projections (64), which are joined to the cover plate (48) at a part of the junction points (62) with the pressure plate (22). Arrangement of pressure plates according to claim 13,
characterized in that the at least one support strip (24) is disposed between its junction projections (64) with a gap (hw) from the cover plate (48). Arrangement of pressure plates according to claim 12,
characterized in that threaded bolts (63) are fixed, essentially perpendicular to the pressure plate (22), to the cover plate (48), preferably at one point of the junction points (62) with the pressure plate (22), by which the at least one support strip (24) is fixed directly or by means of at least one intermediate strip (67) to the pressure plate (22). Arrangement of pressure plates according to any one of Claims 11 to 15,
characterized in that the operating device comprises an arrangement of levers (40,42) articulated to a frame (16) as well as an operating drive member (18) joined to the arrangement of levers (40,42) and preferably comprising at least one cylinder / piston arrangement (44,46) actuable using a fluid. Arrangement of pressure plates according to claim 16,
characterized in that the operating force of the operating drive member (18) is variable, preferably without gradations. Arrangement of pressure plates according to claim 16 or 17,
characterized in that the lever arrangement (40,42) is articulated to the at least one support bar (24). Device (10) for joining a plurality of strips of material (12a, 12b, 12c, 12d), comprising a plurality of arrangements of pressure plates according to any one of the claims previous. Device according to claim 19,
characterized in that the pressure plate arrangements are arranged in the direction of advancement (A) of the strips of material (12a, 12b, 12c, 12d) or / and transverse to this direction of advancement (A) adjacent to each other . Device according to claim 19 or 20,
characterized in that at least a part of the pressure plate arrangements is heatable using a common heating device, preferably being charged with heat transfer fluid. Device according to claim 21,
characterized in that the heat transfer fluid flows successively through the arrangements of pressure plates associated with a common heating device. Device according to claim 21,
characterized in that the heat transfer fluid flows through the arrangements of pressure plates associated with a common heating device in parallel.

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