DE1796263B2 - Process for impregnating corrugated cardboard and device for carrying out the process - Google Patents

Description

The invention relates to a method for impregnating corrugated cardboard running in the direction of the web, their channels, which are open on both sides, extend in the transverse direction and into them along a longitudinal edge if necessary, an impregnating agent is introduced under the action of pressure, if necessary corresponding action of an induced draft along the other slow.

Such a method is known from US Pat. No. 1,592,824, in which the impregnating agent is introduced into the corrugated cardboard ducts. The corrugated cardboard is arranged standing vertically on one edge and running and the liquid waterproofing agent, suitably diluted asphalt, runs from top to bottom under the action of gravity through the corrugated cardboard ducts. This U.S. Patent 1,592,824 contains the advice to bring the material under pressure from above into the Weü ^ upp · - «anal and if necessary to cause a suction draft at the lower edge, but these notes are for the described The procedure is therefore meaningless and cannot be used in conjunction with this procedure because when any pressure or suction conditions act, the specially prepared and equipped corrugated cardboard with funnel-shaped opening, protruding cover layer flaps already through Coincidence of the same would make further processing impossible. At the USA patent is solely based on the effect of gravity to transport the impregnating agent through the corrugated cardboard ducts turned off, which is why you have to work with a liquid impregnation agent. One continuous impregnation in such a way that the impregnation occurs with the same rapidity and speed takes place, with which the corrugated cardboard webs run out of the manufacturing plants, is also not possible, as only individual panels can be brought under the nozzle for processing. Even the displacement of the treated sheets of corrugated cardboard encounters almost unsolvable problems, so that presumably only a relative shift can be realized. In this context, it should be noted that that the process according to this US patent 1,592,824 is a process that is still used today for the impregnation of corrugated cardboard, in which a very large box-shaped container is provided with a conveyor belt, with bars extending in the vertical direction between which the finished ones Boxes, i.e. the blanks or panels, inserted and then passed through a curtain of wax The wax also runs through the corrugated cardboard ducts due to the action of gravity. the In this known method to be expended manual labor from inserting the corrugated cardboard into the Carrier mechanisms up to removal and the time to be expended for treatment are considerable.

Another process for the impregnation of corrugated cardboard, similar to US Pat. No. 1,592,824, can the USA-P.uent 3,343,977 and consists essentially in that the vertically guided Corrugated cardboard web in web direction through a chamber

or a room, although the lower edge must run on rollers, which is easy to do Clogging of the corrugated cardboard duct openings can lead, and from above with the help of a flow chamber of the corrugated cardboard the impregnation agent is supplied, which is then also downward under the influence of gravity flows and the corrugated cardboard in all areas, including on its outer surfaces with the impregnating agent provides.

It seems doubtful whether such a process is technically feasible, in any case it arises here, as well as in the method according to the US patent 1 592 824, the disadvantage that no control over the wax content of the impregnated corrugated cardboard web can be achieved for various reasons is extremely desirable.

However, an actually practiced method for impregnating corrugated board is that A conveyor belt circulates in a very large housing, to which finished blanks of corrugated cardboard are made be clamped by hand and that these blanks then lead through an immersion bath, where the Saturate panels with impregnating agent. The corrugated cardboard sheets then pass through a hot air and a drying chamber and are then manually removed from the conveyor belt. Here too there is the disadvantage that it is of course not possible to control the wax content In addition, such a method is still very cumbersome, complicated and slow in terms of fire hazard.

Finally, the magazine "Tappi 43" (1960) No. 3, pp. 210A to 213A, various coating materials which are suitable for impregnating corrugated cardboard, including foamed ones Plastic. In the following, this publication then mentions various processes and processing options for applying a coating agent to corrugated board, including curtains and fog coaters, which apply a uniform film to rough and flat surfaces can, furthermore, pressure or heating spray units for applying waxes, plastics and high strength coatings, catalytic sprayers for spraying foams on specific Surfaces and the like, but with an internal impregnation, So an impregnation of the corrugated cardboard ducts is rather accidental and not achieved properly can be.

Another publication, namely the magazine "Tappi 46" (1963) issue 1, pp. 172A to 178A You can then coat corrugated cardboard with an impregnation wax using a curtain coater be removed; the corrugated cardboard is cut continuously supplied to a rotating belt, which the blank through a falling film of the coating material Here, too, the impregnating curtain is applied to the outer surface or surfaces of the corrugated cardboard, such as this carried by the continuous belt is deposited. The disadvantages are also mentioned here Impregnation of control over the effective wax content of the impregnated corrugated cardboard and especially the fact that it is not possible in this way, for example the outer surfaces to keep the corrugated cardboard to be impregnated essentially free of the impregnating agent, thereby this can be printed, for example.

The object of the invention is to provide a method for impregnating in the web direction within a normal To create corrugated cardboard plant running corrugated cardboard, which makes it possible that the corrugated cardboard with the Speed, mi! which they go through the manufacturing facility runs, can be provided with an impregnating agent in their corrugated cardboard ducts, the content of which can be set precisely.

To solve this problem, the invention is based on the method mentioned at the beginning and consists according to the invention that the web of corrugated cardboard is continuous is advanced in a horizontal plane and into the channels of the corrugated cardboard at exclusive The effect of suction on the opposite edge is a mixture of particles of an impregnating agent and a gaseous and / or vaporous carrier medium is introduced.

In this way there is the advantage that you can use a low, fully controllable and adjustable Wax content a fully impregnated corrugated cardboard, also double corrugated cardboard can achieve, whereby on the Surface of the impregnated corrugated board excess wax is not deposited, actually the wax content the whole corrugated cardboard can be adjusted so that printing on normal Corrugated cardboard processing machines also impregnated corrugated cardboard and gluing is possible.

It is also of particular advantage that the corrugated cardboard can be processed very quickly and continuously Form is possible, with only a relatively short device must be provided between the short cross cutter and the triplex device of a normal corrugator can be arranged. the Corrugated cardboard coming from the actual corrugated cardboard plant runs through the impregnation station with the same speed with which it is produced and then leaves it grooved and cut.

Further refinements of the invention are the subject matter of the subclaims and are laid down in them.

In the following, the structure and mode of operation of exemplary embodiments of the invention and of the inventive Process explained in detail. It shows

F i g. 1 in a schematic representation an impregnation device in side view,

F i g. 2 is a plan view of the device of FIG

F i g. 3 and 4 each show a detail section of the device according to FIG. 1 on a larger scale,

F i g. 5 shows a modified embodiment of the representation of the h 1 g. 4th

F i g. 6 shows a schematic representation of the course of the impregnation process when running in the direction of the web Corrugated cardboard that

F i g. 7, 8 and 9 show further schematic representations of further possible impregnation processes,

Fig. 10 shows an embodiment of the Einlaufbzw. Squeegee in a perspective view,

F i g. 11 shows a cross section through the squeegee, F i g. 12 shows a cross section through the inlet bar, which

FIG. 13 shows a perspective view of an exchangeable section of the suction bar according to FIG. 11

F i g. FIG. 14 also shows, in a perspective illustration, an exchangeable section of the inlet strip according to FIG Fig. 12, the

F i g. 15 shows in cross section a nozzle which

F i g. 16 a screw plug for a nozzle bore, the

Fig. 17 shows an embodiment of a nozzle structure for introducing the impregnating agent together with a gaseous or vaporous carrier medium into the corrugated cardboard ducts that

Fig. 18 shows a nozzle for a liquid jet and the

F i g. 19 a pressure nozzle for airless injection.

In the case of the in FIG. 1 shown impregnation device 1 passes through the corrugated cardboard sheet 2 with their Longitudinal edges, on the one hand, an inlet strip 3 and, on the other hand, a suction strip 4, both of which as elongated, divided housing are formed. The inlet bar 3 is, as in FIG. 3 shows with guide rails 5 for guiding the corrugated cardboard web 2. The guide rails carry on their outer longitudinal edges on the top and bottom of the corrugated cardboard web 2 adjacent sealing lips 6 made of elastic material. In In a similar way, sealing elements are also in contact with the front and end sides of the inlet strip of the corrugated cardboard 7, as in FIG. 2 indicated, provided. In the embodiment of FIG. 2 closes on Inlet of the inlet bar 3 to the Üichtelement 7 of the inlet bar to an empty zone 8, which by a Suction line 12 is connected to a suction box 32. The empty zone 8 is followed by the inlet zone 9 with the impregnating agent inlets 14, which can be regulated by means of throttle elements 15 (FIG. 3) with adjusting screws 16. To the Inlet zone 9 is followed by a pressure zone 10 for the hot compressed air 7.ufuhr and to the pressure zone 10 one Pressure zone 11 for the cold compressed air supply. The hot and cold compressed air supply is with adjustable inlets 17 (Fig. 2) provided. In the area of the impregnating agent inlets 14, the inlet bar 3 is provided with electric heaters 18 (FIG. 3), whereby they in their Whole is heated. The impregnating agent is in liquid form through a line 19 from an impregnating agent container 20 related. The inlet bar 3 is adjustable by means of a flange 21 (Fig. 1) Mounted frame of the impregnation device and adaptable to the edge of the corrugated cardboard web 2.

In the elongated suction bar 4 (FIGS. 2 and 4) guide rails 22, 23 are installed to guide the opposite edge of the corrugated cardboard web 2, which pass through the housing 4 in a longitudinal slot 24 serving for the inlet of the corrugated cardboard. The longitudinal edges of the guide rails 22, 23 protruding from the longitudinal slot carry flanges 22 ′, 23 ′ which bear against the outside of the housing 4. The flange 23 'is screwed to the housing wall of the suction bar 4, while the flange 22' is adjustable by means of guide slots 25 on threaded bolts 26 of the suction bar 4 and can be locked by nuts 27, so that an adjustment of the guide distance d between the guide rails 22, 23 is possible . On the flanges 22 ', 23' elastic sealing lips 28 are attached, which protrude beyond the outer longitudinal edges of the guide rails 22, 23 and lie against the bottom and top of the corrugated cardboard web 2. With 29 arranged near the outer longitudinal edges of the guide rails 2Z 23 are designated air suction holes. The suction strip 4 consists of separate chambers, each of which is provided with suction nozzle 30 (FIG. 4), which, as in FIG. 1, they are connected to the corresponding chambers of the suction box 32 by hoses 31. These chambers in turn connected by lines 33 to a vacuum pump 34 (and, if necessary, with additional suction units), which is driven by an electric motor 35. The suction box 32 with its chambers serves as a vacuum container and pre-separator. The outlet port of the suction pump 34 is connected by a connecting pipe 36 to an impregnating agent separator 37, from which the recovered impregnating agent is fed to a collecting container 39 through a return line 38, which is only partially indicated. From there, the recovered impregnating agent passes back through a line into the impregnating agent container 20 of FIG. 2.

The impregnation itself takes place in a preferred embodiment as follows: The The finished corrugated cardboard web 2 passes through the impregnation device with both of the longitudinal edges having the open corrugated channels 1 at a speed of 60 to 120 m and more per minute, with the longitudinal edges the corrugated cardboard web on the one hand in the inlet strip 3 and on the other hand in the suction strip 4 under tight Are completed. The suction bar 4 ensures that the air in the corrugated ducts is emptied. In A heater (not shown) is built into the squeegee so that any impregnating agent that may have been sucked in can be absorbed does not precipitate and can cause constipation. As a result of being 2 to 3 m long Suction bar 4 evenly distributed suction nozzle 30, there is a uniform vacuum in the suction bar, which is generated by the vacuum pump 34. Since the suction box 32 also acts as a liquid separator, no liquid impregnating agent can get into the pump 34. From the also heated separator box 37 is then the separated impregnation liquid through a heated pump system, not shown conveyed back into the impregnant tank 20, so that a self-contained cycle of the impregnant arises. The air cleaned of the impregnation agent in the separator box is then used Compressed air organs supplied to the inlet bar in order to utilize the operating pressure of the pump. Under the effect the vacuum generated by the suction strip 4 in the corrugated channels of the corrugated cardboard web 2 becomes the impregnating agent sucked into the corrugated channels of the corrugated cardboard sheet in the area of zone 9 (FIG. 6). thanks to the Heating 18 of the inlet strip 3 has the impregnating agent as desired when it penetrates the corrugated ducts high temperature. Because of the high speeds required for profitable corrugated cardboard production are, the impregnation system is also designed for high performance and equipped with high-performance units. From the speed of the corrugated cardboard web 2 and that under the suction of the squeegee The speed reached by the impregnating agent in the corrugated channels arises, as shown in FIG. 6 shows, of dei Inlet bar 3 to the suction bar 4 is a diagonal flow band 9 '. The subsequent hot compressed air zone IC and cold compressed air zone 11 ensure the drying of the corrugated channels wetted by the impregnation agent.

The aim for the impregnation process is as high a vacuum as possible, continuously and evenly acts moderately and copes with a large amount of air. The higher the vacuum, the greater the acceleration supply and the speed of the impregnating agent in the corrugated channels.

Since the cover layers (outer papers) of the Wellpap pebahn 2 are porous, penetrates the evacuated state Corrugated channels a considerable amount of false air through the pores of the cover layers into the corrugated channels, wa entails a significant loss of vacuum. E has been shown that a front of the impregnation device applied coating medium. about a fine one

409544/31

Water film for the purpose of maintaining an impregnant-free At the same time, the surface of the corrugated cardboard web results in a good seal of the pores and thus increasing the vacuum.

The sealing of the corrugated cardboard can also be achieved with other suitable measures of a mechanical nature be e.g. B. by arranging shielded vacuum zones above and below the corrugated cardboard, in particular, however, also by attaching sealing film strips that roll like a caterpillar, etc.

A preferred method for introducing the impregnating agent into the channels of the horizontally passing Corrugated cardboard web 2 consists in that the liquid impregnating agent is used as a spray, i. H. as a spray in the Corrugated channels arrives, with adjustable metering pumps that can be installed in the inlet side, which carry the impregnating agent Inject with adjustable pressure through nozzles or otherwise press into the corrugated channels. Using a special device, the impregnating liquid can be sprayed under high pressure and extremely fine be sprayed airlessly into the corrugated channels, which enables a particularly intensive impregnation, whereby the impregnating agent is also mixed intensively with air, for example on the principle of a spray gun is sprayed directly into the corrugated channels, which gives the impregnating agent the desired initial speed confers. The impregnating agent is only transported by the vacuum suction, while the Speed of the impregnating agent through the corrugated channels depends on the strength of the air supply. In this context, one can especially use an injection device as shown in FIG. 17th is shown. The injection device shown there consists of a, for example, an Allen screw formed nozzle 53, the continuous cavity 57 of a feed pipe 58 for the liquid impregnating agent is permeated. The feed pipe is concentric with the formation of a Intermediate space 59 in the cavity 57. This intermediate space 59 enables air to enter a pressure chamber 47, as indicated by the dashed arrows 60. The emerging from the space 59 Compressed air tears the impregnating agent flowing into the nozzle through the feed pipe in such a way that a fine spray mist is produced. This spray mist method is particularly suitable for interior treatment corrugated cardboard, as it is possible to work with the finest degrees of wetting and the possibility consists of carrying out the impregnation in such a way that the outer layers of the corrugated cardboard are wholly or partially remain free of the impregnating agent and can therefore be written on, printed on and glued.

The impregnating agent is then subjected to the enormous suction effect of the vacuum created on the squeegee side in the finest atomization and high density together with the sucked air flow into the corrugated cardboard ducts sucked in, the production of such a spray being particularly economical Possibility of introducing a liquid impregnating agent into the corrugated channels of the corrugated cardboard.

Further possibilities, the impregnation agent in the form of a spray:., So an aerosol in the corrugated cardboard ducts introduce, for example, that the impregnating agent in the form of a liquid curtain flows past the openings of the corrugated cardboard ducts and the impregnating agent flows through the The vacuum prevailing in the corrugated cardboard ducts is sucked in; it is also possible to use a suction trough, for example angled slightly downwards, to connect to the openings in the cardboard ducts, in such a way that the Vacuum tears up the liquid impregnating agent located in a suction trough and through the corrugated cardboard ducts sucked through.

This spray mist impregnation method results in a dynamic spray mist or impregnation agent distribution in the by the impregnation device

ίο running corrugated cardboard as shown in the fig. 2 as well as 6 and 7 or in a modification of the procedure also the F i g. 8 and 9 can be seen.

Like F i g. b shows, the inlet section is preceded by a short, active or passive sealing zone 8, which allows the vacuum to build up.

That which penetrated into the corrugated cardboard channels during the passage of the corrugated cardboard through the impregnation device A mixture of particles of an impregnating agent and a carrier medium forms small particles in them Columns which, in their entirety, form a strip 9 'diagonally across the entire width of the corrugated cardboard web during the Form pass that the corrugated cardboard web thereby more or less diagonally in two vacuum zones separates, with the sucking vacuum pulling and the vacuum building up on the inlet side braking works.

Since this braking effect is undesirable and can only occur if the entire inlet side is hermetically sealed, explains the need to directly connect to the inflow zone 9 (for example the F i g. 2, 6 and 7) of the impregnating agent to allow metered air to flow in. Since this air is under normal Air pressure can already penetrate and on the other side of the diagonal strip 9 'still what is desired Vacuum is effective, it can control the flow rate of the impregnating agent or the to accelerate the impregnating agent-containing mixture. Controlled air supply can thus regulate the flow rate of the impregnating agent.

The air supplied to the zones 10 and 11 adjoining the inflow zone 9 on the inlet side can be compressed air in specially developed nozzles under high pressure and high speed is blown directly into the corrugated channels in zones 10 and 11. However, this can be sudden Cooling and stopping the impregnation process lead, so that the compressed air supplied in zone 10 is heated beforehand to at least 120 ° C.

For the final cooling of the impregnated corrugated cardboard ducts, immediately after the Hot air zone 10, cold compressed air is used in zone 11, which is then spread through both sides of the corrugated cardboard web 2 open corrugated cardboard channels volatilized.

The same purpose of cooling also serves in the case of cover layers wetted with a film of water the corrugated cardboard ventilating the same from the outside with a warm or cold air stream the one rapid evaporation of the water film and thus an intensive cooling of the corrugated cardboard.

The inlet strip 3 and the suction strip 4 are also corresponding to the temperature of the impregnating agent heated, which in the area of the inlet bar 3 has the effect that the temperature necessary for the impregnation

G ₅ temperature of the impregnating agent is maintained; In the area of the suction bar 4, however, the impregnating agent residues do not solidify, but get into the separator and from there back to the inlet bar.

So that the vacuum pump 34 develop their full effect it is advantageous to use the main amount of air at the entry of the corrugated cardboard into the impregnation device from the outset to be continuously sucked out of the corrugated cardboard ducts by a separate blower.

Because the spray has a high flow rate reached through the corrugated cardboard ducts, it is advisable to use the after filling the corrugated cardboard ducts Stop the flow of the spray, which is how F i g. 7 shows, can best be achieved in that a hermetic closure area 40 directly adjoins the inflow zone 9 of the inlet strip 3, such a closure area 40 offset opposite one another and adjoining the suction zone 4 ′ is provided.

This then follows in the area of the inlet bar 3 the closure area 40 again a Preßlufteinströmzone 11, which, as already mentioned, is used for cooling and drying the impregnated corrugated cardboard ducts cares. Thus, between the two diagonally opposite end areas 40 is formed a damming zone adjoining the inflow zone 9, which gives the impregnating agent time, into the corrugated cardboard layers to penetrate.

To prevent an excessively high impregnating agent throughput when introducing the from particles of a Impregnating agent and a carrier medium existing mixture can also be added to the mixture special nozzles create a swirling swirl so that the spray mist droplets in the corrugated cardboard ducts be thrown against the inner walls by centrifugal forces. As already mentioned, the Fine-tune the intensity of the impregnation, see above that an impregnation according to the product is possible, in particular it also results in a very economical one Way of working.

It is also possible to divide them into a suction area on the one hand and an inlet area on the other to be replaced by a corresponding arrangement of these zones, whereby in place of the difference these Functions a parallel or mutually graded series of functions is possible, which is illustrated below the F i g. 8 will be explained. When the corrugated cardboard enters the impregnation device, it is initially on both sides the air in the corrugated cardboard ducts is evacuated. then immediately becomes the ruling one Vacuum is filled from both sides with the mixture, which can be a mist, a vapor or a gas. Due to the collision of the two impregnating agent streams, compression is achieved, which is a enables intensive and practically loss-free utilization of the amount of impregnating agent used. In order to prevent the volatile impregnating agent compressed in this way from flowing out, As a result of the further passage, the already mentioned closure areas are closed on both sides 40 at. This parallelism of the impregnation process, which is graded in sequence, is made possible perfect impregnation even with extreme corrugated cardboard widths and despite high * speed the corrugated cardboard. As already mentioned earlier with reference to FIGS. 2 and 6 and 7 respectively, is initially one Empty zone 8 is provided for evacuation, to which the inflow zones 9 and the closure areas 40 connect.

On the basis of FIG. 9 is now a further exemplary embodiment of a method for internal coating of corrugated cardboard ducts explained by means of a spray mist. In the representation of Fig.9 lie the suction zones 4 'and the inflow zones 9 are mutually opposite so that the mixture, d. H. the Spray mist through each inflow zone 9 up to at least half the width of the corrugated cardboard web in the direction of the opposite suction zone 4 'is able to flow. Furthermore, termination areas 40 are shown in FIG provided and on one side a pressure zone 11 for compressed air. The opposite Suction and inflow zones are offset from one another in the running direction of the corrugated cardboard, with on on each side the suction zone 4 'through a closure area 40 from the inflow zone 9 for the spray mist separated isi The pressure zone 11 for the compressed air then takes care of the action of the suction zone opposite it 4 'for the removal or complete distribution of the impregnating agent.

The impregnating agent uptake of the corrugated cardboard papers, d. H. their penetration depth of the impregnating agent depends on various factors. It can be influenced by changing the speed at which the impregnating agent traverses the corrugated cardboard web as well as by changing the temperature of the impregnating agent. Furthermore, the depth of penetration can be influenced by changing the temperature for the various Purposes required air, as well as through its dosage and change in pressure. There is also a stopping the penetration of the impregnating agent by causing an intensive evaporation of a coating medium, a film of water, for example, from the outside, which creates cold on the corrugated cardboard will. Furthermore, the depth of penetration of the impregnating agent also depends on the speed at which the Corrugated cardboard is produced, as well as the use of various impregnating agents and their viscosity.

Taking these factors into account, any desired impregnation is possible for a wide variety of types of corrugated cardboard possible. For example, it is possible to produce completely impregnated corrugated cardboard, which can be seen from the outside with a darker color on both sides, which depends on the impregnating agent chosen is, can distinguish. Furthermore, the production of a partial, i.e. H. more or less heavily impregnated Corrugated cardboard is possible in which both top layers are "light". Another type of partial impregnation consists in the fact that the corrugated cardboard is "light" on one side and "dark" on the other. or that one side is completely impregnated and the other side is partially impregnated is, with areas that are kept completely free as required by targeted wetting from the outside can. In this case, the corrugated cardboard has a "dark" top layer on one side and the other Side on a top layer with "dark" and "light" areas. The partial impregnation can also be carried out in such a way that the corrugated cardboard has "dark" and "light" fields on both sides, whereby the latter through the partial use of a coating medium, such as a water film, of are generated outside. If there is less corrugated cardboard, only one corrugated layer can be coated with impregnating agent so that only the outer layer that is particularly required for impregnation, possibly also the inner layer, is partially or fully impregnated

The wetting of the cover layers before, during unc after the impregnation zone represents hot impregnation average because of the evaporation process caused by the heat

would take moisture to maintain the desired corrugated cardboard and thus serves a double purpose. The suction prevailing in the anal waves also pulls part of the water film enters the paper pores where it enters the hot medium is re-evaporated. The shielding is created because of the slower flow velocity of water against the air pushing in, and by wetting the topmost paper layer, the impregnating agent becomes hindered from the complete penetration of the m cover layer.

Since the high speed of the corrugated board means that the wetting time is short to increase the penetration capacity, softened the water by adding it. Same purpose also serves to increase the water temperature.

Another way to achieve a reliable seal of the cover layer is that instead of water, a coating medium is applied in a film-like manner to the top layer and inside the corrugated cardboard creates a vacuum. A combination of both types of application can be done from the inside at the same time are impregnated with a hot-melt impregnation agent, with an aqueous, cold-soluble plastic emulsion takes over the functions of the water film in such a way that the Water content of the emulsion is volatilized by the heat of the hot-melt impregnating agent, so that a tough, tear-resistant outer layer made of plastic is created.

Another measure to reduce the false surface air is the shielding of the same by sealing cavities above and below the impregnation zone. In their passive function These cavities become through the pores of the paper through the vacuum prevailing in the corrugated channels evacuated and, once emptied, form protective vacuum zones. On the other hand, it can be far more effective Device can be designed by placing both the upper and lower protective shells with the evacuated Cavities have a direct vacuum connection to a blower or a vacuum pump. So can even an external vacuum which is superior in strength to the internal vacuum can be built up, so that in addition the pulling suction creates a suction from the inside to the outside, which causes that to happen at high speed z. B. impregnating agents flowing through in the form of Sprey droplets additionally from the inner area the corrugated channels are drawn outwards to the paper layers and from there particularly intensively in penetrates the pores of the paper. Further vacuum zones 8 serve to seal off false air infiltration points the inputs and outputs of the impregnation device.

By regulating the vacuum conditions between inside and outside, or the amount of false air, which is still able to penetrate, the penetration capacity of the impregnating agent can also be controlled will.

The same device for creating vacuum zones can also be used in the opposite direction to set up pressure zones through which reactive gases are pressed into the paper pores in order to cause a particularly intensive reaction there with a reactive impregnant that penetrates from the inside to the outside. it provement impregnation as well as another way to control the lmprä ₆ itiervorgangcs GCGC ben is.

By means of heating plates above and below the corrugated cardboard can be moved into the impregnation station False air penetrating pores of the cover papers can be influenced. The heat makes the air above the Paper warmed up so that it rises. This results in a pressure relief. The one penetrating into the pores In addition, hot air keeps the impregnation agent hot longer and warms up the paper considerably for easier penetration of the impregnating agent. In the case of impregnating agents introduced in powder or dust form, z. B. Powdered paraffin, the hot air penetrating the paper pores causes the immediate Fusion of the individual particles.

Instead of heating plates, a device can also be used to generate a magnetic field with the aim of to attract the previously oppositely dielectrically polarized impregnation agent and thus to deposit on the Bring paper sheets. Proves to be particularly beneficial This method is useful for easily moving impregnating agents such as sprays, powders and the like For the same purpose, metallic additives that are added to such a medium can also be used, to serve. The dielectric polarization of the impregnation agent can also be achieved without magnets by the corrugated cardboard itself already has a static charge, which can be increased by suitable measures, forms the opposite pole to the introduced medium, which has been dielectrically polarized accordingly.

For the implementation of all impregnation processes it is important that both on the inlet side and on the Suction side well sealed on all sides, d. H. Seals clinging to the corrugated cardboard (e.g. elastic Sealing strips) are provided. At the ends of the guide rails, which can be adjusted depending on the thickness of the corrugated cardboard 5 and 22, 23 (Figs. 3 and 4), sealing strips 6 and 28 made of flexible material are mounted in such a way that that they press against the corrugated cardboard passing through under the effect of the suction, as already explained at the beginning. Instead of the sealing strips, the guide strips 5 or 22, 23 can also be narrow, in the through have sealing ridges 5 'running in the direction of travel of the corrugated board, as shown in FIG Emboss the top layers of the corrugated cardboard passing through. The lateral entry points for the corrugated cardboard sheet are also provided with snug-fitting sealing elements. A particularly good seal will be achieved by continuously adapting to the horizontal displacements of the corrugated cardboard sheet passing through Inlet and suction strips. The best solution to this problem is that the impregnation device represents a closed unit, so that only ever for the entry and exit of the corrugated cardboard there is an adjustable slot, with the inlet and suction side being interconnected by a closed housing are connected.

The F i g. 10 to 17 now show still further embodiments of the individual elements forming the impregnation device, whereby initially on the in F i g. 10 shown Insertion head 43 will be discussed in more detail, whose zone area formed in the impregnation device corresponds to the empty zone 8 at the beginning of the suction bar 4 or inlet bar 3. The insertion head 43 provides for the smooth reception of the outermost corrugated cardboard web edges, which are designated in Fig. 12 with 2 ', and bends the cover layers 2 "of the corrugated cardboard web about plow-like, unless they are trimmed beforehand have been so that they can run into a cavity 44 without stoppages occurring. The deck

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layers 2 ″ lie against stop surfaces 44 ' in such a way that the openings of the corrugated cardboard channels directly in front of the suction slots 49 of a suction strip sub-element, as shown in FIG. 11 is shown, or before Nozzle openings 46 of the inlet strip element of FIG. 12 slide past. In the guide head 43 of the Fig. 10 causes the stop surface 44 at the same time a seal of the corrugated cardboard channels, which then subsequently to be evacuated.

As already mentioned, in FIGS. 11 and 12 off Light metal existing standard elements for the inlet strip 3 and the suction strip 4 are shown, in this case Inlet bar 3 or suction bar 4 made of at least two such standard elements and an insertion head according to FIG. 10 exist.

In Fig. 13 is such a, the suction bar 3 to be assigned Standard element is provided with the reference number 51 and shows in a perspective illustration the in F i g. 11 standard element shown in cross section. Each standard element has a closed suction or Pressure space 47 and a connecting piece 48. The suction slot of the suction strip 3 to be assigned Standard element 51 is denoted by 49, such a standard element can be exchanged as desired, not only within the suction strip 4, but also against a standard element of the inlet strip 3, if a mutual suction is provided. For this purpose, connecting and guide elements 50 are released and the standard element 51 withdrawn from continuous steam lines 52. There are guide and connecting elements on the front 50 mounted, which are adjustable and can be adapted to any type of corrugated cardboard; they form together with special sealing combs 54 and spacer and connecting elements 55 form a fixed unit. To readjust the sealing combs 54, the latter is released.

The standard elements 51 'of the infeed bar 3, which are shown in FIG the F i g. 12 and 14 are shown, form self-contained units that have their own cavities for the impregnating agent and have compressed air.

Stabilizing, connecting and guiding elements are provided for both standard elements 50 and 51 50, 55 and 56 together with steam lines 52 and give the whole thing in screwed State a stable unit.

This is expediently drawn on not specially drawn Rolling rails stored and by tension and compression springs on a slight snug fit with respect to the corrugated cardboard web 2 adjusted. Guided in this way, the inlet bar 3 and squeegee 4 can move easily adapt to the moving corrugated cardboard web. This ability makes the impregnation device A high degree of efficiency is ensured in every phase of the passage of the corrugated cardboard web.

Thanks to the separate suction and pressure chambers and the associated connections, it is possible that, for. B. on On the suction side, some standard elements of the suction strip 4 are connected to a vacuum pump, but others are connected to a blower be, so that to adapt to the desired operating conditions slightly variations to are to be accomplished. The same also applies with regard to the inlet strip 3 for the impregnating agent, the hot and cold compressed air. The fine-tuning of the individual components, on the other hand, is carried out by the Replacing the various nozzles 53 according to FIG. 14 against those of greater or lesser capacity. For this purpose, the adjusting screws of the front guide and connecting elements 50, 55 must be loosened and the latter are displaced up and down in adjusting slots (not shown) on the blocks 5Γ. The screw-in and screw-out nozzles 53, which are provided with Allen keys or slots, make a necessary Replacement of nozzle sets done quickly.

Another way of regulating the impregnation agent offers the use of a metering pump known per se, not shown. Both here and even with the compressed air the different ones can be opened

ίο Control the pressures acting on the impregnating agent.

At the two ends of the input and the suction side, bearings for receiving wetting rollers or sealing beads can advantageously be arranged above and below, the shafts of the latter being held rigidly in a bearing only at one end, so that the other end in the opposite bearing slide and thus can adapt to the movements of the impregnation device.
Finally, FIGS. 15 to 19 show nozzle arrangements made from common Allen screws and therefore cost-saving, with the nozzle in FIG. 17 has already been discussed in more detail above, which is shown in FIG. 15 is a nozzle for introducing compressed air, it corresponds to that in

As the standard element 5Γ of Fig. 12 inserted nozzle, F i g. 16 does not have a longitudinal bore and can therefore be used wherever a medium flows in is not desired, it therefore serves as a plug for nozzle bores and replaces in these cases the normal nozzle, the fig. 18 shows a nozzle for generating a liquid jet and FIG. 19 a pressure nozzle for injecting the impregnating agent in airless form.

A large number of substances and materials can be used as impregnating agents, for example Plastics, water glass, bitumen, paraffins, resins. Glues, paraffin-bitumen emulsions, synthetic resin-wax mixtures, liquid plastics, foaming plastics, synthetic resins, silicones, sodium silicate solutions, Alkali metal silicates, vinyl resins, etc., some of which also serve as fillers.

In this context, the foaming of the corrugated channels with a curable material is of particular importance Plastic foam, as this way completely new stability and insulation conditions even with corrugated cardboard can be created. When foaming the corrugated cardboard with self-hardening plastic foam the foam, if it is composed of two or more components, is immediately in front of it the introduction into the corrugated cardboard ducts automatically mixed intensively, so that the foam in more homogeneous liquid form enters the corrugated channels. One filled with plastic foam and impregnated In addition to the gain in stability, corrugated cardboard has an extraordinarily high insulation value and is suitable therefore particularly suitable for the transport of temperature-sensitive products, but also for use in the construction sector. The foaming of the corrugated cardboard channels still enables the without any loss of quality Use of corrugated cardboard with extremely large waves.

The corrugated cardboard can also be printed before it enters the impregnation device, with the used printing ink counteracts the penetration of the impregnation agent, so that a similar effect arises, like when applying a water film. A water color can possibly be used as the printing ink will. Both this printing device and

The coating system can also use the impregnation device be assembled so that they form a single machine unit.

An even finer level than the spray is the evaporation of the impregnating agent and its subsequent Injection as steam. The vacuum evaporation takes on a special meaning here, because of it the vacuum the evaporation point is lowered. The impregnating agent can be used in a special provided vacuum containers are made to evaporate, with the steam in more or less compressed form is sucked into the shafts. The vapor impregnating agent can but can also be blown in at a temperature such that it is in the corrugated channels under vacuum additionally evaporated from a state of the finest nebulisation.

Depending on the requirements, the impregnating agent can be supplied in various forms, for example a / s liquid, spray, vapor, powder, foam, mist, gas, dust, etc., being the particles of the impregnating agent then each form a mixture with a gas and / or vaporous carrier medium. That Impregnation agent can be a hot-melt or cold-soluble agent with volatile components, an emulsion or, as already mentioned, a foaming plastic.

The impregnating agent can be sprayed with or without air - what is meant is how it comes from the nozzle assigned to it - directly into the corrugated cardboard ducts; can be sprayed, but it can also be processed into a fine and moist mist in a compression chamber that is heated if necessary and then sucked through the corrugated channels. The imprä eniermittpl tonn; _n »:« ~ w- · - ■

Very fine atomized sprays are introduced into the white cardboard ducts of the corrugated cardboard and there, be it due to the moisture content of the corrugated cardboard. Temperature, dielectric polarization or external mechanical effects can be brought to uniform adhesion to the layers. The powdery impregnation agent unfolds its effect through the entry of a connection with the components of the paper used (sodium ίο or by being melted by the inherent heat of the corrugated cardboard or by special drafts of hot air When using cold, aqueous plastic emulsions, it is advantageous to attach the impregnation device over the last heating plates of the drying section of the actual corrugated cardboard machine so that the water contained in the emulsion can sufficiently evaporate on the further way and the corrugated cardboard impregnated by this or a part thereof can also be brought into a dielectric state for certain purposes.

Due to the extremely high speed that the spray mist reaches inside the corrugated cardboard ducts, can use the impregnation device as a short, high-performance unit between the short cross cutter 41 and in front of the triplex cut-crease station, which makes it possible to cut the corrugated cardboard to impregnate during the running production in their entire production width, as the for this necessary temperature of the corrugated cardboard is given here and then cut and / or creased. That has

_o _ "" ₆ ^ ,, yytiucii. uds impra- then cut and / or creased. That has

Lubricant can be hot or cold in a vacuum chamber 35 the great advantage that all Wellkaiialöffnungen

are sprayed and vacuum evaporated and are still undamaged open and the impregnating agent

this vacuum chamber is then not impaired as a moist impregnation when it flows through,

gnoving agent vapor is sucked through the corrugated ducts only after impregnation is the processing

be genes. Finally, it is possible to impregnate the corrugated cardboard using the cutting and creasing station, where ·

medium through a carburetor in gaseous state to 40 with the shaft channels are partially depressed. the

offset and when sucking through a sealing, the corrugated cardboard is therefore in the area in which the im-

Paper fibers interlinking reaction is carried out, already finished, each

to solve. but still a certain moisture content and

Another possibility for impregnation is above all a temperature (about 70 to 90 ⁰ C), which for

Dusting the corrugated ducts with powder or 45 impregnation is of considerable importance.
dusty impregnating agents similar to the

In addition 7 sheets of drawings

Claims (32)

Patent claims: 1. Process for impregnating corrugated cardboard running in the direction of the web, whereby both sides of it open channels extend in the transverse direction and optionally into these along a longitudinal edge an impregnating agent is introduced under the action of pressure, with appropriate action if necessary an induced draft along the other longitudinal edge, characterized in that the corrugated cardboard web continuously in a horizontal Level is advanced and into the channels of the corrugated board with exclusive action of the induced draft at the opposite edge a mixture of particles of an impregnating agent and a gaseous and / or vaporous carrier medium is introduced. 2. The method according to claim 1, characterized in that the impregnating agent is under pressure is supplied airless and the carrier medium (air) is added when it is sucked into the corrugated cardboard ducts will. 3. The method according to claim 1 or 2, characterized in that at least one outer The surface of the corrugated cardboard is sufficiently thick before the actual impregnation process Layer of a coating medium is applied such that an outward migration of the impregnant from the channels on the outer surfaces of the corrugated cardboard is prevented. 4. The method according to claim 3, characterized in that a water film is used as the coating medium is used. 5. The method according to any one of claims 1 to 4, characterized in that the impregnating agent and / or the carrier medium is heated before being introduced into the corrugated cardboard ducts. 6. The method according to any one of claims 1 to 5, characterized in that the impregnating agent is evaporated before being introduced into the corrugated cardboard ducts, preferably vacuum evaporated. 7. The method according to any one of claims 1 to 6, characterized in that the impregnating agent a plurality of longitudinally spaced feed areas relative to the Corrugated cardboard is fed and that the inflow of impregnating agent is selective for the individual areas is regulated. 8. The method according to claim 7, characterized in that excess impregnating agent means various discharge areas, which are kept at a distance from one another in the longitudinal direction, are discharged, whereby the vacuum is selectively adjusted in these areas. 9. The method according to any one of claims 1 to 8, characterized in that the impregnating agent when it is supplied, a swirling swirl is imparted in such a way that the particles of the impregnating agent be thrown against the inner walls of the corrugated channels by centrifugal force. 10. The method according to claim I, characterized in that a liquid impregnating agent curtain and its atomization and introduction into the corrugated cardboard ducts by exiting nozzles Compressed air is achieved. 11. The method according to any one of claims I to 10, characterized in that after the mixture of impregnating agent and carrier medium has been introduced dosed cold or hot air is admitted into the corrugated cardboard ducts. 12. The method according to one or more of the languages to I to 11, characterized in that be Very large corrugated cardboard web widths from both sides, graduated approximately to the middle of the corrugated cardboard web is impregnated. 13. The method according to claim 12 characterized draws that the impregnating agent from both Be th in successively staggered Zonei wire embedded in the corrugated cardboard ducts under the action of an opposing suction zone and in each case the inflow zones for the impregnation medium from the suction zones by final report be separated. 14. The method according to any one of the claims! until 13 characterized in that the corrugated cardboard ducts are additionally evacuated through the cover layers will. 15. The method according to one or more of the claims 1 to 14, characterized in that before introducing the mixture of impregnating agent and carrier medium a vacuum is established on both sides of the corrugated cardboard ducts. Iu. Method according to one of Claims 1 to 15 characterized in that the impregnating agent and the corrugated cardboard to be treated are dielectrically polarized state. 17. The method according to any one of claims 1 to 16, characterized in that as impregnation and / or filler foamable plastic is used. 18. The method according to claim 17, characterized in that the components of the plastic are mixed with one another before being introduced into the corrugated cardboard ducts. 19. The method according to any one of claims 1 to 16, characterized in that as an impregnating agent an impregnating agent in powder, powder or dust form is used. 20. The method according to one or more of claims 1 to 19, characterized in that at multi-corrugated corrugated cardboard at least one corrugation and the corresponding blankets are impregnated. 21. Device for impregnating corrugated cardboard running in the direction of the web Channels open on both sides extend in the transverse direction and, if necessary, along a longitudinal edge in this direction an impregnation medium can be introduced under the action of pressure, optionally with a corresponding one Effect of an induced draft along the other longitudinal edge, preferably for implementation of the method according to one or more of claims 1 to 20, characterized in that that a device for the continuous horizontal guidance of the corrugated cardboard (2) with each side the longitudinal edges of the corrugated cardboard (2) arranged inlet strip (3) or suction strip (4) is provided is that by means of the suction bar (4) simultaneously in a plurality of successive channels of the Corrugated cardboard can be produced with suction during its horizontal advance, and that the suction bar (4) and inlet ledge (3) extending in the horizontal direction and the associated corrugated cardboard edge have receiving recesses (22, 23; 5). 22. The device according to claim 21, characterized indicates that for the introduction of the impregnating agent in the inlet bar (3) nozzles (53) are provided, into which the feed pipe (58) for airless, pressurized introduction of the impregnating agent opens. 23. The device according to claim 21, characterized in that for introducing the tinning medium and thus an annular channel concentrically surrounding the feed pipe to form the mixture (59) is provided 24. The device according to one or more of claims 2i to 23, characterized in that the infeed bar (3) has a plurality of feed areas that are spaced apart from one another in the longitudinal direction (8, 9, 10, ii) includes rule arrangements (15, 16) to adjust the supply of impregnating agent and air 25. The device according to claim 24, characterized in that at least one additional feed area (10, 11) is arranged in the longitudinal direction, which feeds hot compressed air and / or cold compressed air to the corrugated cardboard ducts. 26. The device according to one or more of claims 21 to 25, characterized in that the suction bar (4) likewise into a multiplicity of individual suction areas divided in the longitudinal direction is divided, with devices for setting ucs Extent of the respective vacuum in the suction areas. 27. The device according to one or more of claims 21 to 26, characterized in that Inlet rail (3) and suction rail (4) or the recesses receiving the longitudinal edges of the corrugated cardboard (22, 23; 5) elastic sealing means (6, 28) are assigned to at least one of the horizontal Grasp the outer surfaces of the corrugated cardboard (2). 28. Device according to one or more of claims 21 to 27, characterized in that the suction bar (4) is assigned a suction box (32) which is connected to a vacuum pump via lines (33) (34) is in connection, and that the suction box as a vacuum container and separator (suction box separator) serves for the impregnation agent, which can be fed back to the inlet bar (3). 29. The device according to one or more of claims 21 to 28, characterized in that for atomizing a liquid curtain of impregnating agent by means of compressed air emerging from nozzles (53) is provided. 30. Device according to one or more of claims 21 to 29, characterized in that the impregnation agent from both sides in zones arranged one after the other under action a suction area (4 ') opposite in each case can be introduced into the corrugated cardboard ducts Closing areas (40) for separation and subsequent cooling and drying by compressed air. 31. The device according to one or more of claims 21 to 30, characterized in that to reduce false surface air above and below the corrugated cardboard shields against following air are attached. 32. Device according to one or more of claims 21 to 31, characterized in that the impregnation device between the short cross cutter, where the impregnation is necessary Temperature of the corrugated board is given and the triplex cut-crease station the corrugated cardboard plant is arranged.