Abstract:
A machine and method is provided for applying a fluent adhesive or glue to a surface in two or more parallel strips at a adjustable distance apart. The machine has a plurality of glue nozzles mounted on a radius of a suspension device, which has an arcuate shape and is pivotable about the axis of the radius of the arc. The parallel adhesive strips are accomplished by applying the glue to the surface while moving the surface linearly past the nozzles. Adjustment of the distance apart is accomplished by rotation of the arc of the suspension device about its pivot axis by a swivelling means, which alters the angular distance between the nozzles relative to the direction of movement.

Description:
[0001]     The present application claims the benefit of prior filed European Patent Organization Application, serial number EP 05 011979.1 filed 3 Jun. 2005, to which the present application is a regular U.S. national application. FIELD OF THE INVENTION  
         [0002]     The present invention is in the field of machines, devices and methods for the application of adhesives in at least two parallel tracks.  
       BACKGROUND OF THE INVENTION  
       [0003]     When processing printed products, but also in other fields, there is a need to apply two or more parallel glue breads, in order to be able to glue on for example a book cover or the like.  
         [0004]     Within the printing field one talks about so-called side coating, which consist typically of two glue beads running parallel to each other on each side of an already bound book block. These glue beads run along the bound back on the front and back side of the book block. After application of the side glue the back of the book, or another cover is then put and pressed around the back of the book provided with side glue.  
         [0005]     One of the problems in the field lies in the fact that a machine for applying the side glue should be applicable as flexibly as possible, so that it can be adapted fast and problem-free with respective to a specific printing order. This presupposes that on the one hand the distance between the glue beads must be adjustable and that on the other hand such a machine should be adaptable also to the thickness of the respective book which is to be glued.  
         [0006]     In the past side glueing machines drums are used, which are guided through a glue basin, in order to then apply the necessary glue coating on the book block. This approach is particularly complex with PUR-based adhesives, since PUR hardens relatively quickly if exposed to air. In addition, the re-configuring of such a machine can be relatively complex. The conventionally working machines are also problematic if glue beads with a distance of less than 10 mm have to be applied.  
         [0007]     Therefore it is an object to provide a glue application device and a machine based on such a device which allows easy and flexible application of at least two glue beads running parallel to each other. In addition, a corresponding method is to be provided.  
         [0008]     It is regarded to be particularly important that a precise adjustability of the distance between glue strips of less than 10 mm is possible. In addition the application of the glue must be homogeneous and reproducible. It is also important that the devices and machines are suited for processing PUR-based glue or Hotmelt.  
       SUMMARY OF THE INVENTION  
       [0009]     The present invention includes a glue applying device, a machine incorporating the glue application device, and a method for using the device and machine in combination to reproducibly apply at least two glue beads running parallel to each other. In addition, a corresponding method is to be provided. It is a particularly important feature of the invention that it is possible to precisely adjust the distance between glue strips to distance of less than 10 mm.  
         [0010]     The glue application device is capable of applying glue capable of flowing in two strips summing essentially parallel on surface. The glue device comprises at least two nozzles, mechanically fastened to a suspension member. The nozzles are mechanically fastened and arranged with respect to each other at a given distance apart. The suspension member has an arc-shaped toothed segment disposed to mate with a pinion gear. The pinion meshes with the toothed segment, and rotation of the pinion around a pinion axis is converted into a rotation of the toothed segment around a suspension axis, whereby the suspension member is swivelled around the suspension axis by of rotation of the pinion. By swivelling the suspension member, the distance between the parallel running strips is adjustable.  
         [0011]     In a preferred embodiment, the pinion gear is controlled and driven by a manual means, (e.g., a crank handle), or by an engine or motor. In this embodiment, the glue applying device is mounted in combination with a machine of which the pinion gear and drive means comprise a part. It is a feature of the present embodiment that a continuous (or step-less) drive means, like the pinion and toothed gear mechanism, provide very precise adjustability of the distance between adjacent glue line of between 0 and 10 mm. The invention is particularly suitable for the application of glue with variable strip distance. The distance can be adjusted very easily and exactly. Further advantages of the invention can be derived from the figures and the following description.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is a perspective view of a preferred embodiment of a glue application device of the present invention.  
         [0013]      FIG. 2  is a side view of the preferred embodiment of a glue application device of  FIG. 1 .  
         [0014]      FIG. 3A  is a schematic sectional view of a book block with cover.  
         [0015]      FIG. 3B  is a cutout enlargement of the  FIG. 3A .  
         [0016]      FIG. 4A  is partial side view of a further glue application device of the invention showing application of a single glue line to a surface.  
         [0017]      FIG. 4B  is partial side view of the glue application device of  FIG. 4A  showing how swivelling of the device relative to  FIG. 4A  provides for controlled adjustment of the distance between two parallel glue lines.  
         [0018]      FIG. 5  is a further partial side view of a glue application device of the present invention.  
         [0019]      FIG. 6  is a schematic side view of two glue application devices disposed to apply glue lines to two sides of a book block.  
         [0020]      FIG. 7  is perspective view of a preferred embodiment of the present invention in which two glue application devices are combined in a glueing machine.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     Referring now to the drawings, the details of preferred embodiments of the present invention are graphically and schematically illustrated. Like elements in the drawings are represented by the like numbers, and any similar elements are represented by like numbers with a different lower case letter suffix.  
         [0022]     The present invention concerns a machine comprising at least one glue application device for use in the application on a surface of two or more glue paths running parallel to each other. These paths are also called glue beads. In  FIGS. 1 and 2 , a preferred glue application device  10  according to invention is shown. The glue application device  10  is part of a machine  40  (see  FIG. 7 ). The glue device  10  serves in the example shown for applying fluid glue in two essentially parallel running strips  23  or  24  on an object or surface  20 , see  FIGS. 3A and 3B . In accordance with invention the device  10  comprises two nozzles  11 . 1 ,  11 . 2  and a suspension member  14  to which the two nozzles  11 . 1  &amp;  11 . 2  are mechanically fastened and arranged with respect to each other, so that their mutual distance A is given, as shown in  FIG. 2 . Although only a pair of glue nozzles  11 . 1  &amp;  11 . 2  are shown in the figure, one of ordinary skill in the art knows that more than two such nozzles are intended and can be practiced in the present invention. The suspension  14  may comprise several elements  14 . 1 ˜ 14 . 5 . Further a mounting block  15  or the like is provided.  
         [0023]     The suspension member  14  has an arc-shaped toothed segment  12  connected to it. In the embodiment illustrated, the arc-shaped toothed segment  12  comprises teeth  12 . 1  external to the arc-shape. A pinion gear  13  meshes with the toothed segment  12 . The toothed segment  12  and the pinion  13  are arranged with respect to each other and dimensioned so that rotation of the pinion  13  around a pinion axis R 1  is converted into a rotation of the toothed segment  12  around a rotation axis R 2 . Thereby also the suspension member  14  moves around the axis of rotation R 2 . In the preferred embodiment illustrated, the axis of rotation R 2  runs through the first glue nozzle  11 . 1  (see for example  FIG. 6 ), which configuration provides that the distance d between the back  22  of the book and the first nozzle  11 . 1  always remains constant.  
         [0024]     In  FIGS. 3A and 3B  further details of the principle according to the invention are recognizable.  FIG. 3A  shows a side view of a book block  20  with a cover (book cover  21 ). The insert marked with an L is shown with magnification in  FIG. 3B .  FIG. 3B  shows a condition of the book block  20  after applying two pairs of parallel glue beads  23  &amp;  24  running on both sides of the book block  20 . The distance A 1  between glue beads  23  on one side of the book block  20  and the distance A 2  between the glue beads  24  on the other side of the block  20  can be unequal. The distance d from the first glue bead  23  &amp;  24  on a side to the back of the book  22  is typically is constant. However, the distance d between the back  22  of the book block  20  and the first glue strip  23  &amp;  24  can be separately adjusted on each side.  
         [0025]     By swivelling the suspension member  14 , the distance A 1  and/or A 2  between the parallel running bead strips  23  &amp;  24  can be adjusted, as described in  FIGS. 4A and 4B . In a preferred embodiment, with the glue nozzles in a zero-position (angle W=zero), application of glue to the surface can be controlled so that both nozzles  11 . 1  &amp;  11 . 2  deliver glue alternating. Thus both nozzles are loaded more evenly. With the suspension member  14  in the zero-position (W=0), only a single glue strip  23  is applied, since both nozzles if viewed in the direction of motion B lie one behind the other.  
         [0026]     In  FIGS. 4A and 4B , a part of the elements  14 . 1 ,  14 . 3 ,  14 . 4  &amp;  14 . 5  of the device  10  called suspension member  14  is shown. In addition, the two nozzles  11 . 1  &amp;  11 . 2  are visible. In  FIG. 4A , a configuration is shown where the suspension member  14  has not been swivelled, and where thus both glue nozzles  11 . 1  &amp;  11 . 2  are in line with each other relative to the direction of motion B (i.e., W=0). If in  FIG. 4A , glue is dispensed from one or both of the two nozzles  11 . 1  &amp;  11 . 2 , only one glue beads  23  results. The direction of motion B of the object or surface relative to the glue nozzles  11 . 1  &amp;  11 . 2  is shown in  FIGS. 4A and 4B . The glue beads  23  extend parallel to the direction of motion B.  
         [0027]     If now the suspension member  14 , including the glue nozzles  11 . 1  &amp;  11 . 2 , is turned in a counter-clockwise direction (angle W≠0), the configuration shown in  FIG. 4B  results. Now if at the same time glue is dispensed from both nozzles  11 . 1  &amp;  11 . 2 , two glue beads  23  running in parallel to each other are applied to the object. The glue beads  23  extend parallel to the direction of motion B. Since the two glue nozzles  11 . 1  &amp;  11 . 2  are offset in parallel to the direction of motion B, glue beads  23  running in parallel to each other result, which begin with an offset distance B 1 , as indicated in  FIG. 4B . The distance between the two glue beads  23  is denoted with A 1 . In a particularly preferred embodiment, the offset distance B 1  is equalized, by the glue dispensing from the two nozzles  11 . 1  &amp;  11 . 2  being controlled in such a way that the nozzle  11 . 1  begins to deliver glue somewhat later than the nozzle  11 . 2 . That is, the spatial offset distance B 1  is preferable eliminated by an appropriate temporal offset (so that B 1 =0 or is reduced). This feature is indicated in  FIG. 5 .  
         [0028]     In the  FIG. 6  parts of a machine  30  according to the invention are shown. The machine  30  comprises in the example shown two devices  10 . 1  &amp;  10 . 2 , which can be implemented similarly or equal as in the  FIGS. 1 and 2 .  FIG. 6  is a schematized illustration in which one can recognize the two devices  10 . 1  &amp;  10 . 2  and the object  20  (a book block without book cover or binding). The relative movement of the object  20  in relation to the devices  10 . 1  &amp;  10 . 2  runs perpendicularly to the paper plane and is indicated by B. The device  10 . 1  has not been swivelled by the rotation of the mentioned pinion. Therefore, the strip distance A 1  corresponds to the distance A of the two nozzles. The distance A 1  is maximum since R 2  runs through one of the nozzles  11 . 1 . The device  10 . 2  however, was swivelled by the rotation of the mentioned pinion  13  and the strip distance A 2  thus is smaller than the distance A between the two nozzles  11 . 1  &amp;  11 . 2 .
 
( A=A 1 &gt;A 2).
 
 Preferable by a proper gear combination of pinion  13  and toothed segment  12 , a reduction in the degree of rotation is obtained. In a particularly preferred embodiment, the gear ratio of the pinion  13  to the tooth dear  12 . 1  is about established so that upon revolution of the shaft  13 . 1  a linear enlargement or reduction of the strip distance A 1  or A 2  is obtained. Preferably by the combination of pinion  13  and toothed gear  12 . 1  a reduction into the slow is obtained. “A reduction into the slow” is a technical phrase used in gear technology to describe that a faster motion is translated into a slower motion. For example, if one turns the pinion gear  13  360 degrees, the toothed segment  12 . 1  will only turn a small fraction of the 360 degrees. In  FIG. 6 , only a part  14 . 1  &amp;  14 . 4  of the suspension member  14  is visible. The toothed segment, the pinion and the further elements are not shown. Moreover, this design is not drawn to scale. 
 
         [0029]      FIG. 7  shows further details of an alterative machine  40 . The object  20  is not shown, since it would otherwise cover a part of the elements. Two glue application devices  10 . 1  &amp;  10 . 2  are both shown in a perspective representation. An end-to-end shaft  13 . 1  is provided, which can be turned by the manual rotation of a knob  41 . The rotation of the shaft  13 . 1  is transmitted via a first pinion (not shown) to a toothed segment  12  of the device  10 . 1  and via a second pinion (not shown) to a toothed segment  12  of the device  10 . 2 . By the rotation of the knob  41  attached to the pinion shaft  13 . 1 , the suspensions members  14  of both glue application devices  10 . 1  &amp;  10 . 2  can be swivelled. Due to this, as already described, the strip distance A 1  can be adjusted steplessly. Alternatively, the machine  30  or  40  comprises a pinion shaft  13 . 1 , which is driven by a motor (not shown).  
         [0030]     Beside some elements, which are not essential for the invention, the glue supply  42  is shown in  FIG. 7 . As one can recognize, the glue supply has two separate lines, i.e. one line per nozzle  11 . 1  &amp;  11 . 2 . Control of the machine  40  can be designed so that the glue application initiates at the same time, or, as described on the basis  FIG. 5 , temporally offset. The temporal offset is preferred, since one can equalize with it the spatial offset B 1 , which is caused by the rotation. In another embodiment of the machine  40 , only one glue supply is intended per device  10 . 1  &amp;  10 . 2 . In this case, at least one of the nozzles comprises a closing means (e.g., a valve), in order to eliminate the spatial offset B 1  or to be able to reduce it. In a further preferred embodiment, the control nozzle control feature is disposed so that application of an intermittent strip is possible. Each individual strip can be configure as dots, dashes or strip-shaped.  
         [0031]     In a further preferred embodiment, the machine  30  &amp;  40  is provided with a mechanical and/or electrical display, in order to indicate the size of the strip distance A 1  &amp; A 2 . An embodiment is particularly preferred where there is a feedback between the adjusted strip distance A 1  &amp; A 2  and the temporal offset. In this case, the control is in the position to determine from the currently adjusted strip distance the necessary temporal offset between the glue dispensing from the first nozzle  11 . 1  and the glue dispensing from the second nozzle  11 . 2 .  
         [0032]     In a further embodiment of the invention, the axis of rotation R 2  does not run through any of the glue nozzles  11 . 1  &amp;  11 . 2 , but runs between the nozzles  11 . 1  &amp;  11 . 2 . In this case, a symmetrical arrangement is preferred, where the two glue nozzles  11 . 1  &amp;  11 . 2  have the same distance to the axis of rotation R 2 . The suspension member  14  can have two, three or more nozzles  11  arranged parallel to each other. With an odd number of nozzles  11 , the axis of rotation R 2  can preferably run through the middle nozzle  11 . The distance A between adjacent nozzles preferably is 10 mm. This enables a step-less and very precise adjustment between 0 and 10 mm, if the axis of rotation R 2  runs through one the two nozzles.  
         [0033]     A machine  30  &amp;  40  according to the present invention is useful in connection with the binding of paper (e.g., a book block) or cardboard. The machines  30  &amp;  40  can be designed so that they can process a book block  20  with a thickness t between 1 and 100 mm. The book block length l can be, for example, between 100 mm and 600 mm. Typically, the speed of the translatory relative motion B is between 5 m/min and 200 m/min. The machines  30  &amp;  40  can comprise a heating element, in order to make or keep the glue fluid capable of flowing. Depending upon the embodiment, with the present invention cardboard can be moved with a speed between 100 m/min and 300 m/min, preferably with a speed between 120 m/min and 180 m/min, past the nozzles  11 / It is also preferable that the adhesive in the nozzle  11  is at an idle pressure, in order to be able to immediately deliver glue in the desired quantity after starting the device. By such a measure the device can be stopped at any time, an ready to then start again. With is feature, waste is drastically reduced.  
         [0034]     While the above description contains many specifics, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of one or another preferred embodiment thereof. Many other variations are possible, which would be obvious to one skilled in the art. Accordingly, the scope of the invention should be determined by the scope of the appended claims and their equivalents, and not just by the embodiments.