US3896763A - Impregnating corrugated cardboard - Google Patents

Impregnating corrugated cardboard Download PDF

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Publication number
US3896763A
US3896763A US321840A US32184073A US3896763A US 3896763 A US3896763 A US 3896763A US 321840 A US321840 A US 321840A US 32184073 A US32184073 A US 32184073A US 3896763 A US3896763 A US 3896763A
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United States
Prior art keywords
flutes
jet
cross
nozzle
impregnating
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Expired - Lifetime
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US321840A
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English (en)
Inventor
Gunther Lau
Edmund Bradatsch
Hermann J Brandl
Georg Niggel
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    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
    • D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
    • D21H23/22—Addition to the formed paper
    • D21H23/50—Spraying or projecting

Definitions

  • ABSTRACT An apparatus for impregnating corrugated cardboard with a waterproofing or protective material is described.
  • the corrugated board including a plurality of laterally extending open ended flutes is fed between an impregnant supply means and a suction means.
  • the impregnant supply means includes a nozzle means for injecting a concentrated jet of impregnating material a substantial distance into said laterally extending flutes.
  • the cross-sectional area of the concentrated jet is smaller than the cross-sectional area of said flutes in the provision of a gaseous medium surrounding said jet at the entrance of said flutes.
  • the suction means creates a vacuum which draws the impregnating material of said jet and the surrounding gaseous medium through said flutes.
  • Means are provided for adjusting the position of said nozzle means with respect to said corrugated board and the quantity of impregnating material supplied to said flutes. Means are further provided for sensing the presence or absence of the corrugated board in area of said nozzles and for cutting the impregnant supply means on or off in response thereto.
  • the present invention relates to an apparatus for impregnating rapidly moving corrugated board, having a succession of transversely extending open ended longitudinal flutes therein, wherein the impregnating material is injected into a first end of said flutes, under pressure, in the form of a concentrated jet of impregnating material having a cross sectional area less than the cross sectional area of the flutes into which it is injected, while a suction means is disposed adjacent the opposite ends of the respective flutes for drawing said impregnating material in said jet and any surrounding gaseous medium through said open ended flutes to thereby impregnate the interior of the corrugated board.
  • the impregnating material may be selected from the group consisting of plastics, water glass, bitumen, parafin, resin, glue, paraffin-bitumenized emulsion, artificial resin wax mixture, liquid synthetic materials, foaming plastics, artificial resins, silicon, sodium silicate solution, alkali metal silicate, vinyl resin, and any other material which would occur to one of ordinary skill in the art to provide durability and waterproofing to corrugated cardboard.
  • the apparatus of the present invention facilitates the penetration of the concentrated jet of impregnating material a substantial distance into the flutes or ducts in a direction transverse to the movement of said corrugated board. This causes a considerable amount of the flutes or ducts to be impregnated, even before the suction action from the opposite sides of said flutes enhances or continues the flow of the impregnating material through the flutes of said corrugated cardboard.
  • the presence of a gaseous medium surrounding the concentrated jet of impregnating material provides a high pressure differential between the side of said flutes in which the impregnating material is injected and the vacuum created in the suction means at the opposite end of the flutes.
  • This pressure differential causes the gaseous medium surrounding the jet at the entrance end of said flutes to be drawn through the flutes at a rapid rate, wherein the movement of the gaseous medium helps carry the impregnating material of the jets the remainder of the distance through said flutes.
  • the apparatus of the present invention permits a very uniform weight application of the impregnating material coupled with maximum production speed. Furthermore, good variability of application coupled with good reproducibility are obtained. Finally, minimum machine length because of the fast feed rate of the impregnating material laterally through the corrugated board is facilitated.
  • the injection jet has the shape of a full jet, a flat jet, or a broadslit jet. If the broad-slit jet is used it is possible to further shorten the structural length of the machine, because now fewer nozzles are needed next to each other in the direction of movement of the corrugated paper course.
  • the device for implementing the method according to the invention with at least one nozzle associated with the one open longitudinal edge of the corrugated board for the injection of the concentrated jet of impregnating agent into the corrugated board, the nozzle is placed as closely as possible to the longitudinal edge of the corrugated board to permit the jet to penetrate as deeply as possible into the board before the suction means draws the material the remainder of the distance.
  • the height of the nozzle can be adjusted, according to another feature of the invention, that is, it can be swung around an axis parallel to the direction of movement of the corrugated board. Furthermore, the nozzle can be adjusted with respect to the longitudinal edge of the corrugated board.
  • FIG. 1 illustrates a schematic vertical cross-section through the apparatus for impregnating a corrugated board according to the present invention
  • FIG. 2 is a top plan view of the apparatus of FIG. 1;
  • FIG. 3 is a schematic vertical cross-section through a first embodiment of an injection nozzle of the present invention
  • FIG. 4 is a top view of the nozzle of FIG. 3;
  • FIG. 5 is a vertical cross-section of a second embodiment of an injection nozzle for use with the present invention.
  • FIG. 6 is a top view of the nozzle of FIG. 5;
  • FIG. 7 is a vertical cross-section of a third embodiment of an injection nozzle for use with the present invention.
  • FIG. 8 is a top view of the nozzle of FIG. 7;
  • FIG. 9 is a top plan view of the apparatus according to the invention illustrating control means for turning the nozzles on or off;
  • FIG. 10 is a schematic vertical cross-section of the apparatus of FIG. 9.
  • the device for impregnating a corrugated board as illustrated in FIGS. 1 and 2 consists of an application device generally designated 1 and a suction means 2 disposed on opposite sides of a corrugated board 3, which is to be impregnated with an impregnating material.
  • the impregnating device is inserted inline into an installation for the production of the corrugated board, where the corrugated boards to be produced are moved along a horizontal plane at a rapid rate past the impregnating device.
  • the corrugated board is supported by longitudinal guides 6 and 7.
  • the longitudinal guide 6 consists of a fixed lower angular guide rail 8 and an upper, angular guide rail 9, which can be adjusted vertically and which can be fixed in position.
  • the guide parts 10 and 11 of the longitudinal edge guide 7 can be integral with suction means 2.
  • the application device 1 includes at least one nozzle 12, a distributor means 13, and a control unit 14.
  • the impregnating material which is pressurized by a pump (not shown) is moved, via pipeline 14, to the control unit 14 and from there via the distributor means 13 on to the nozzle 12.
  • the control unit 14 can be operated pneumatically or electromagnetically.
  • a suitable switchable routing valve (not shown) of the control unit 14, in one switching position, facilitates the free passage of the impregnating material to the nozzles 12, while the second switching position connects the feed line 15 with a return line for the impregnating agent, so that, even after the nozzles are shut off, the impregnating material can be recirculated to avoid stoppages or the like.
  • control unit 14 we can control two nozzles 12 due to the use of the distributor means 13. As can be-seen from FIG. 2, a large number of nozzle control units 12, 13, and 15, next to each other, may be provided.
  • the carrier 16 of the nozzle control unit 12, 13, 14 can be adjusted vertically in the direction of arrow I. It can also be adjusted horizontally in the direction of arrow II, and it can be swung around an axis parallel to the longitudinal edge of corrugated board 3 in the direction of arrow III.
  • nozzle 2 has the form of a flat-jet nozzle which generates a sharp, fan-shaped jet.
  • the nozzle bore-hole 17 turns into a nozzle exit opening 18 whose cross-section, in the horizontal plane, has the shape of a circular segment while it is triangular in the vertical plane.
  • other forms can be used for the nozzle outlet opening 18.
  • the essential thing is that the nozzle outlet opening 18 should guide the impregnating agent jet 19 as completely as possible into the interior 20 of the corrugated board, whereby the jet can be fanned out more or less, parallel to the corrugated horizontal plane.
  • the cross-sectional area of jet 19 allows the entry of a gaseous medium in the arrow direction indicated in FIG. 3 into the corrugated board in the area surrounding jet 19. This presupposes that the nozzle opening 18 is at a short distance from longitudinal edge 4 of the corrugated board 3.
  • the nozzle opening 18 should be placed as closely as possible to the longitudinal edge 4 of the corrugated board 3 because otherwise there is a danger that an essential portion of the impregnating material jet 19 will not penetrate a sufficient distance into the interior 20 of the corrugated board.
  • the opposite edge of the corrugated board is connected to a suction means 2 which includes a vacuum pump with a prepositioned impregnating material cutter, not shown.
  • the corrugated board interior 20 is, as usual, subdivided into ducts or flutes which are separated from each other and which run laterally to the direction of movement of the corrugated board.
  • the inside wall of these canals is impregnated by means of the impregnating agent.
  • the impregnating agent is impregnated over a substantial distance from the longitudinal edge 4 by the penetration of the impregnating material jet 19.
  • the impregnating material which comes out of the nozzle exit opening 18 under high pressure is eventually reduced to very fine droplets toward the end of its path of injection. These droplets gradually cling to the wall of the lateral corrugated flutes.
  • the air or gaseous medium which is drawn through the corrugated board facilitates the further transport toward the longitudinal edge 5 of the impregnating material in jet 19. This air or gaseous medium acts as a carrier for the impregnating material as it is drawn through the interior of the board.
  • Surplus impregnating substance is swept along into the suction means 2 and there it is separated by a cutter (not shown) and is recirculated to the impregnating agent pump or to a container connected to that pump.
  • the air or gaseous material is blown out via the cutter from the vacuum pump, preferably a liquid seal pump.
  • the nozzle mouthpiece, with nozzle duct 17 and nozzle exit opening 18 is exchangeable as we can see from FIGS. 5-8.
  • FIGS. 5 and 6 there is illustrated a second embodiment of the nozzle 18 of the present invention which generates a broad-slit jet.
  • the nozzle has a rectangular crosssection in the vertical plane and a circular cross-section in the horizontal plane.
  • FIGS. 7 and 8 there is illustrated a third embodiment of the nozzle of the present invention for generating a full-jet.
  • Nozzle 18 in the embodiment of FIGS. 7 and 8 has a triangular cross-section in the vertical plane and a linear cross-section in the horizontal plane. It should be understood that other nozzle configurations may be used without departing from the spirit and scope of this invention.
  • the present invention also offers the advantage that the pressure of the impregnating material pump can be changed, by virtue of the fact that the valve opening can be reduced or that the nozzle opening can be changed by means of a closing needle which can be screwed into the bore of nozzle 18 to adjust the crosssection of the nozzle opening to facilitate the adjusting of the quantity of the impregnating material injected into the corrugated board,
  • the quantity of impregnating material injected would be adjusted according to the relative speed of the corrugated board.
  • the pressure of the impregnating material pump could also be changed as a function of the speed of the board.
  • Adjustments of the quantity of impregnating material may be accomplished continually or phase-by-phase. If a large number of nozzles are provided, which are arranged as closely as possible in juxtaposition and can be controlled as described above, then a situation might occur where it may be desirable to adjust the nozzles in any desired sequence. As the movement speed of the board increases, nozzles which were shut off could be turned on, whereas they could be selectively shut off as the speed of movement of the board decreases.
  • one or more sensors may be provided which respond to the presence of the corrugated board.
  • one sensor at the inlet and at the outlet to facilitate the actuation of the nozzles only when both sensors have been activated by the corrugated board which has come in. This may be accomplished by connecting both sensors to a conventional AND gate in suitable logic circuitry.
  • the impregnating apparatus is turned off, as soon as the inlet sensor is no longer activated by the passing corrugated board. The last piece of the corrugated board of course is then no longer impregnated but we can reliably prevent the apparatus from being sprayed full.
  • the sensors 21 can be combined with nozzles 12 for the passing corrugated board 3, whereby the pertinent control units successively turn on or successively turn off the individual nozzles, controlled by the incoming or outgoing corrugated board 3.
  • the sensors for the presence or absence of the corrugated board 3 can also sense the position of the corrugated board and control the position of the corrugated board edge in the guides.
  • Position sensors can additionally be provided on the suction side, preferably at the inlet and the outlet.
  • sensors 21 may be microswitches or light and photocell means, which can detect the presence or absence of objects as is well known in the art.
  • the air or gaseous medium, which is sucked in on the suction side via the corrugated flutes is preferably preheated, for which purpose it is conducted on the suction side via a heat exchanger, not shown.
  • air can also be forced via the heat exchanger through a blower into the corrugated paper canals. This makes it possible to preheat apparatus parts, such as, for example, the nozzles and the like, which have become cold, while starting the apparatus.
  • Apparatus for impregnating corrugated board including a serpentine fibrous intermediate layer, and a top and bottom planar fibrous outer layer having a predetermined height therebetween and cooperating with the serpentine layer to define a succession of transversely extending open-ended flutes having said predetermined height, comprising a. means for longitudinally feeding said board with said flutes and said planar outer layers being arranged horizontally and with said flutes extending normal to the longitudinal direction of feed;
  • stationary impregnant supply means arranged adjacent one longitudinal edge of said longitudinally travelling board for supplying to one end of the flutes adjacent thereto an impregnating material, said impregnant supply means including 1. nozzle means for injecting a concentrated jet of said impregnating material, substantially devoid of air into said flutes, said concentrated jet having a height less than said predetermined height of said flutes, between said top and bottom layers 2.
  • said nozzle means being provided with a bore hole and an exit aperture having a cross-section taken in a vertical plane through the bore hole which is substantially triangular when viewed perpendicular to the cross section, and a crosssection taken in a horizontal plane through the bore hole which is substantially semicircular when viewed perpendicular to the cross section;
  • said nozzle means and longitudinally feeding means being positioned such that said one longitudinal edge is positioned away from said nozzle means for allowing a gaseous medium entry to the flutes adjacent said nozzle means and concentrated jet as said concentrated jet is injected into said flutes for sheathing said jet as it enters said flutes, and
  • stationary suction means disposed adjacent the other longitudinal edge of said board opposite said impregnant supply means for establishing a vacuum in said flutes to draw the impregnating material in said jet and said surrounding gaseous medium therethrough.
  • Apparatus for impregnating corrugated board including a serpentine fibrous intermediate layer, and a top and bottom planar fibrous outer layer having a predetermined height therebetween and cooperating with the serpentine layer to define a succession of transversely extending open-ended flutes having said predetermined height, comprising a. means for longitudinally feeding said board with said flutes and said planar outer layers being arranged horizontally and with said flutes extending normal to the longitudinal direction of feed;
  • stationary impregnant supply means arranged adjacent one longitudinal edge of said longitudinally travelling board for supplying to one end of the flutes adjacent thereto an impregnating material, said impregnant supply means including 1. nozzle means for injecting a concentrated jet of said impregnating material, substantially devoid of air into said flutes, said concentrated jet having a height less than said predetermined height of said flutes, between said top and bottom layers 2.
  • said nozzle means being provided with a bore hole and an exit aperture having a cross-section taken in a vertical plane through the bore hole which is substantially rectangular when viewed perpendicular to the cross section, and a crosssection taken in a horizontal plane through the bore hole which is substantially semicircular when viewed perpendicular to the cross section;
  • said nozzle means and longitudinally feeding means being positioned such that said one longitudinal edge is positioned away from said nozzle means for allowing a gaseous medium entry to the flutes adjacent said nozzle means and concentrated jet as said concentrated jet is injected into said flutes for sheathing said jet as it enters said flutes, and
  • stationary suction means disposed adjacent the other longitudinal edge of said board opposite said impregnant supply means for establishing a vacuum in said flutes to draw the impregnating material in said jet and said surrounding gaseous medium therethrough.
  • Apparatus for impregnating corrugated board including a serpentine fibrous intermediate layer, and a top and bottom planar fibrous outer layer having a predetermined height therebetween and cooperating with the serpentine layer to define a succession of transversely extending open-ended flutes having said predetermined height, comprising a. means for longitudinally feeding said board with said flutes and said planar outer layers being arranged horizontally and with said flutes extending normal to the longitudinal direction of feed;
  • stationary impregnant supply means arranged adjacent one longitudinal edge of said longitudinally travelling board for supplying to one end of the flutes adjacent thereto an impregnating material, said impregnant supply means including 1. nozzle means for injecting a concentrated jet of said impregnating material, substantially devoid of air into said flutes, said concentrated jet having a height less than said predetermined height of said flutes, between said top and bottom layers 2.
  • said nozzle means being provided with a bore hole and an exit aperture having a cross-section taken in a vertical plane through the bore hole which is substantially triangular when viewed perpendicular to the cross-section, and a crosssection taken in a horizontal plane through the bore hole which is substantially linear when viewed perpendicular to the cross section;
  • said nozzle means and longitudinally feeding means being positioned such that said one longitudinal edge is positioned away from said nozzle means for allowing a gaseous medium entry to the flutes adjacent said nozzle means and concentrated jet as said concentrated jet is injected into said flutes for sheathing said jet as it enters said flutes, and
  • stationary suction means disposed adjacent the other longitudinal edge of said board opposite said impregnant supply means for establishing a vacuum in said flutes to draw the impregnating material in said jet and said surrounding gaseous medium therethrough.

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US321840A 1972-01-14 1973-01-08 Impregnating corrugated cardboard Expired - Lifetime US3896763A (en)

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DE2201744A DE2201744C2 (de) 1972-01-14 1972-01-14 Verfahren und Vorrichtung zur Hohlraumimprägnierung einer Wellpappenbahn

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4047497A (en) * 1976-01-26 1977-09-13 Grobler Johannes H Apparatus for impregnating constructional elements
US4987022A (en) * 1988-03-21 1991-01-22 Keisuke Ueno Non-inflammable light-weighing tough board
US20050000421A1 (en) * 2003-07-03 2005-01-06 Claudio Meisser Device for wetting cable-ends
US20060048899A1 (en) * 2002-09-13 2006-03-09 Ruediger Duwendag Device for placing a paper bag bottom
PL422374A1 (pl) * 2017-07-27 2019-01-28 Kartonex Spółka Z Ograniczoną Odpowiedzialnością Sposób impregnowania tektury falistej i zespół urządzeń do impregnowania tektury falistej

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1592824A (en) * 1921-10-31 1926-07-20 Mid West Box Company Waterproofing corrugated board
US3043014A (en) * 1957-05-31 1962-07-10 Celotex Corp Drying of gypsum board
US3348519A (en) * 1964-06-29 1967-10-24 Columbian Carbon Automatic glue dispensing apparatus
US3669064A (en) * 1970-02-09 1972-06-13 Boise Cascade Corp Apparatus for impregnating corrugated cardboard
US3669067A (en) * 1967-09-29 1972-06-13 Boise Cascade Corp Apparatus for impregnating corrugated cardboard

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD82421A (de) *
DE869291C (de) * 1942-07-23 1953-03-02 Erich Juenemann Vorrichtung zum Aufbringen von Leimstreifen auf Papierschlaeuche
DE821322C (de) * 1950-01-24 1951-11-15 Wirtschaftskontor G M B H Pneumatischer Zerstaeuber fuer teigige oder pastenartige Massen

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1592824A (en) * 1921-10-31 1926-07-20 Mid West Box Company Waterproofing corrugated board
US3043014A (en) * 1957-05-31 1962-07-10 Celotex Corp Drying of gypsum board
US3348519A (en) * 1964-06-29 1967-10-24 Columbian Carbon Automatic glue dispensing apparatus
US3669067A (en) * 1967-09-29 1972-06-13 Boise Cascade Corp Apparatus for impregnating corrugated cardboard
US3669064A (en) * 1970-02-09 1972-06-13 Boise Cascade Corp Apparatus for impregnating corrugated cardboard

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4047497A (en) * 1976-01-26 1977-09-13 Grobler Johannes H Apparatus for impregnating constructional elements
US4987022A (en) * 1988-03-21 1991-01-22 Keisuke Ueno Non-inflammable light-weighing tough board
US20060048899A1 (en) * 2002-09-13 2006-03-09 Ruediger Duwendag Device for placing a paper bag bottom
US7731647B2 (en) * 2002-09-13 2010-06-08 Windmoeller & Hoelscher Kg Device for placing a paper bag bottom
US20050000421A1 (en) * 2003-07-03 2005-01-06 Claudio Meisser Device for wetting cable-ends
US7685964B2 (en) * 2003-07-03 2010-03-30 Komax Ag Device for wetting cable-ends
PL422374A1 (pl) * 2017-07-27 2019-01-28 Kartonex Spółka Z Ograniczoną Odpowiedzialnością Sposób impregnowania tektury falistej i zespół urządzeń do impregnowania tektury falistej

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DE2201744A1 (de) 1973-07-19
DE2201744C2 (de) 1982-04-22

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