Abstract:
An exchangeable glue cartridge to be used in a bookbinding machine comprises a retaining arrangement which forms a self-adjusting or adjustable jaw wherein the platform of the glue cartridge can be pushed in such a way that the glue spreading roller is downward or remains downward. The jaw limits the vertical mobility of the glue cartridge in both directions by limiting the mobility of the platform. In addition, the system comprises at least one rotatable converter for transmitting the motion to at least one rotating device located in the glue cartridge while the glue cartridge is mounted in place. By means of the self-adjusting or adjustable jaw it is possible to increase the manufacturing tolerances of the glue cartridge and to prevent the glue cartridge from getting blocked in the system.

Description:
TECHNICAL FIELD 
       [0001]    The invention is related to the field of bookbinding. 
       BACKGROUND INFORMATION 
       [0002]    The demand for hot-melt adhesive binding machines or perfect binding machines has increased strongly in recent times. This is partly due to the rapid development of digital printing technology. Using this type of machines it is possible to produce books in small series and even single copies of books in an economically sensible way. The operating principle of the popular perfect binding machine offered by the applicant has been described in international patent application published as printed document WO 03/064169 A1. 
         [0003]    A photo book can be mentioned as an example of books produced in small series or in single copies. Along with the breakthrough of digital camera and image processing technology, the demand for photo books has increased greatly. 
         [0004]    When state-of-the-art digital printing technology, with the paper passing through many rollers and cylinders, is used for printing, the best end product is nowadays obtained by printing on coated and/or strongly glazed paper grades. The print quality is then brilliant at best, and it is possible to achieve a color rendering of images that is very close to the desired color rendering. 
         [0005]    Experience shows that the best result in bookbinding using the perfect binding method is achieved when the book is made of uncoated and unglazed paper. However, it is not possible to print on this kind of paper by means of the state-of-the-art digital printing technology in such a way that the end product would be comparable to printing carried out on coated and/or strongly glazed paper grade. 
         [0006]    Perfect binding for small series is nowadays most commonly carried out by means of EVA hotmelt (EVA=ethylene-vinyl-acetate-copolymer). The processing temperature of EVA hotmelt is approx. 170° C., and the adhesive must be applied to the spine of the book to be bound during a so-called open time, which is approx. 10 to 60 seconds, during which the adhesive is not yet cured and is still processible. The EVA hotmelt within the bookbinding machine will melt again when heated. 
         [0007]    Industrial bookbinding is nowadays increasingly carried out by means of PUR adhesive (more accurately: polyurethane hot-melt adhesive). The processing temperature of PUR adhesive is approx. 130° C. The PUR adhesive already cures during cooling but, for the final curing, the PUR adhesive absorbs additionally moisture from the air. The adhesive undergoes then transition into insoluble urea. This kind of cured PUR adhesive cannot be remelted when heated. 
         [0008]    Binding by means of EVA hotmelt is not as heat-resistant as binding by means of PUR adhesive. The PUR adhesive enables to achieve a better bonding strength than the EVA hotmelt for certain paper grades. However, the use of PUR adhesive is more complicated than the use of EVA hotmelt because bookbinding machines using PUR adhesive require intensive cleaning to be able to continue using the machines. 
         [0009]    As regards the above-mentioned paper grades and the quality aspects of printing, both EVA hotmelt and PUR adhesive have their advantages. However, as things are developing, the result may be that future bookbinding machines are expected to allow the use of both EVA hotmelt and PUR adhesive. A solution to this demand, anticipated by the applicant, is presented in a patent application published on 7 Aug. 2013 as printed document EP 2 623 212, viz. an exchangeable glue cartridge making the use of a bookbinding machine easier. 
         [0010]    An exchangeable glue cartridge presents many advantages compared for example with the “EZ-Clean Tank” arrangement of Horizon International, Inc., referred to in the patent application mentioned here. 
       SUMMARY OF THE INVENTION 
       [0011]    The purpose of the invention described in the present application is to facilitate the use of a perfect binding machine by improving the availability of exchangeable glue cartridges. 
         [0012]    The system for using an exchangeable glue cartridge according to the present invention is meant to be used in combination with a glue cartridge comprising i) a glue tank as well as a platform connected to it, ii) a rotatable glue spreading roller connected to the glue tank, arranged directly below the glue tank and designed in such a way that the shape of the glue spreading roller prevents glue from escaping from the glue tank when the glue spreading roller is in place, on the one hand, and taking glue from the glue tank when the glue spreading roller is being rotated, on the other hand, as well as iii) at least one rotating device, available outside the glue tank, for rotating the glue spreading roller. 
         [0013]    The system for using an exchangeable glue cartridge comprises at least one retaining arrangement forming a self-adjusting or adjustable jaw into which the platform of glue cartridge may be pushed in such a way that the glue spreading roller is pointing downward or remains downward and which is configured to limit the vertical mobility of the glue cartridge in both directions by limiting the mobility of the platform. In addition, the system comprises at least one rotatable converter for transmitting the motion to at least one rotating device in the glue cartridge while the glue cartridge is mounted in place. 
         [0014]    The inventor has discovered that exchanging the glue cartridge described in the printed document EP 2 623 212 becomes easier if the system is used, thanks to the self-adjusting or adjustable jaw. 
         [0015]    By using the system, it is thus possible to allow for a greater tolerance variation of the glue cartridge platform dimensioning. Even if the glue cartridge platform were somewhat thicker or thinner, the self-adjusting or adjustable jaw enables to mount the glue cartridge in the system and, on the other hand, to hold it firmly in place. 
         [0016]    By using the system, it is thus also possible to prevent problems caused by a possibly different thermal expansion or different stages of thermal expansion between the system and the glue cartridge. When the system is cold (e.g. at room temperature), it is possible to mount a hot glue cartridge (e.g. one which is at operating temperature) therein, or a cold glue cartridge (e.g. one which is at room temperature) can be mounted in a hot system (e.g. one which is at operating temperature). 
         [0017]    According to an advantageous aspect, the jaw can comprise at least one shoulder as a shape-limited upper limit for the glue cartridge in vertical direction. In addition to this, or as an alternative to this, the jaw can comprise at least one resilient or resiliently mounted lower part. If the jaw comprises at least one shoulder, as described above, the resilient or resiliently mounted lower part is most advantageously movable toward the shoulder and/or away from it. The resilient or resiliently mounted lower part is an effective way of implementing the self-adjusting jaw because the resilience enables to position the glue cartridge in the system very accurately to a large degree irrespective of any possible manufacturing tolerances and varying thermal expansion of the different parts of the system, as well as of any differences in temperature between the system parts (and glue cartridge) during mounting. 
         [0018]    According to an advantageous aspect, the lower part can be a heater or it can contain a heater. In this case, at least one heater is most advantageously arranged in such a way that it heats the platform of the glue cartridge from below. The inventor has discovered that this increases the operating reliability of the glue cartridge. Particularly advantageously, the heaters form a pair arranged in such a way that it heats the platform of the glue cartridge from both sides of the glue spreading roller. In this way, heat is conducted from the platform into the glue spreading roller, which ensures that glue at the glue spreading roller can be better kept at processing temperature. The arrangement also speeds up the warming-up of glue cartridge. 
         [0019]    According to an advantageous aspect, the retaining arrangement can comprise at least one pair of supporting elements or arms between which the glue cartridge can be mounted. In this case, the jaw is implemented by means of the supporting elements or arms. The projection or lower part is (or both are) thus most advantageously a part of the supporting elements or arms. 
         [0020]    According to an advantageous aspect, the mutual dimensioning of the platform and supporting elements or arms can be implemented in such a way that at least one narrowed part remains on one side or on both sides between the platform and the supporting elements or arms, whereby a gap remains between them at the narrowed part (or narrowed parts). The narrowed part (or narrowed parts), which can be implemented e.g. by removing material from the guide surfaces of the glue cartridge so that only the necessary small guide surfaces remain, can be used to reduce the contact surface between the glue cartridge and the supporting elements or arms so that an air gap remains between the glue cartridge and the supporting elements or arms. This helps to better avoid the conduction of dissipated heat into the supporting elements or arms. 
         [0021]    According to an advantageous aspect, the system can comprise a spring system for pressing or pushing the glue cartridge toward the second retaining arrangement in horizontal direction. In this way, the correct mutual orientation of the converter in the system and the at least one rotating device in the glue cartridge can be ensured better: When the distance from the converter (e.g. from torque converter) to the retaining arrangement (e.g. arms) is adequate, the glue cartridge is pressed against the second retaining arrangement while the shaft of the glue spreading roller is aligned with the axle line of the converter. With the distance from the converter to the surface of the shoulder of the opposite retaining arrangement (e.g. arm) being greater than that from the glue spreading roller to the edge of the left-hand shoulder of the glue cartridge, a gap remains between the glue cartridge and said opposite retaining arrangement. 
         [0022]    According to an advantageous aspect, the system can additionally comprise a half-open side heater, a half-open surface heater and/or a half-open jacket heater which uses the heat to be conducted through the side walls, surface and/or jacket surface of the glue tank for heating the glue in the glue tank of the glue cartridge mounted in place. Thanks to the half-open heaters, the glue cartridge can be simply pushed into its place in the system. This makes it easier to mount the glue cartridge in the system compared with the solution described in printed document EP 2 623 212 according to which the heater is placed separately around the glue tank. 
         [0023]    The side, surface and/or jacket heater is best positioned against the glue tank while the glue cartridge is mounted in place. The jacket surface of the jacket heater is most advantageously in the shape of a cylindrical segment. This enables to arrange the necessary heating for the glue cartridge with the minimum possible heat dissipation. 
         [0024]    If the side, surface and/or jacket heater is resiliently mounted, e.g. by means of compression springs, this enables to press the heater tightly against the glue tank. Thanks to the resilient mounting of the heater, the system can be implemented within simply achievable manufacturing tolerances. 
         [0025]    According to an advantageous aspect, the system can also comprise a releasable locking mechanism for preventing the removal of the glue cartridge mounted in place. By means of the closed locking mechanism it is possible to prevent removal of the glue cartridge from the receiving unit by mistake. 
         [0026]    By means of the system, which additionally comprises a glue cartridge mounted in place, wherein a converter available outside the glue cartridge is arranged to rotate the rotating device of the glue cartridge, whereby the glue spreading roller can be rotated by means of the converter, it is possible to better avoid any damages possibly caused by the use of an incorrectly mounted glue cartridge, because the converter must be connected to the rotating device of glue cartridge so that the glue spreading roller would rotate. Depending on the implementation, a prerequisite for the rotation of the glue spreading roller is that the glue cartridge is perfectly or at least almost at the correct position. 
         [0027]    According to an advantageous aspect, the system can also contain a fixed or a detachable setting device for removing the glue cartridge from the system or for mounting it in the system. This makes it easier to mount the hot glue cartridge in the system, to mount the glue cartridge in the hot system, as well as to remove the glue cartridge from the hot system. 
         [0028]    A bundle of sheets to be bound to make a book can be set into the bookbinding machine. Adhesive can be applied to the spine of the bundle by means of the bookbinding machine in such a way that the adhesive can be taken from a glue cartridge by using the system. In this way, it is possible to utilize the machine geometry known from the Fastbind Elite-type perfect binding machine also in a perfect binding machine using a glue cartridge. Thanks to the self-adjusting or adjustable jaw of the system, the mounting of glue cartridges is easier even if the glue cartridges have a different temperature than the system. It is also possible to reduce the operating costs of the bookbinding machine as the tolerance requirements of the glue cartridges can be widened thanks to the system. 
         [0029]    Advantageously, the bookbinding machine comprises a backwards and forwards movable glue spreading unit, configured to rotate the glue spreading roller or an exchangeable glue cartridge while the glue spreading unit is moved backwards and forwards, whereby the glue contained in the glue tank can be applied to the spine of the bundle of sheets. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein: 
           [0031]      FIG. 1  shows the glue cartridge and the cover of a glue cartridge; 
           [0032]      FIG. 2  shows an exploded view of the glue cartridge presented in  FIG. 1 ; 
           [0033]      FIG. 3  shows a rear view of the glue cartridge presented in  FIG. 1 ; 
           [0034]      FIG. 4  shows a side view of the glue cartridge presented in  FIG. 1  from the right; 
           [0035]      FIG. 5  shows a bottom view of the glue cartridge presented in  FIG. 1 ; 
           [0036]      FIG. 6  shows a top view of the glue cartridge presented in  FIG. 1 ; 
           [0037]      FIG. 7  shows a glue cartridge equipped with a cover to which a mounting plate is being attached for fixing a setting device; 
           [0038]      FIG. 8  shows a system for using the exchangeable glue cartridge with a glue cartridge being mounted therein by means of the setting device; 
           [0039]      FIG. 9  shows a system wherein the glue cartridge is mounted in place, with an open locking latch; 
           [0040]      FIG. 10  shows a side view of the system presented in  FIG. 9  from the left; 
           [0041]      FIG. 11  shows the system presented in  FIG. 9  after removing the setting device, with a closed locking latch; 
           [0042]      FIG. 12  shows a side view of the system presented in  FIG. 11  from the left; 
           [0043]      FIG. 13  shows the heater implemented as lower part; 
           [0044]      FIG. 14  shows an exploded view of the glue cartridge receiving unit, illustrating the mounting of the heaters presented in  FIG. 13 ; 
           [0045]      FIG. 15  shows an exploded view of the glue cartridge receiving unit, illustrating the mounting of the heater for the glue cartridge; 
           [0046]      FIG. 16  shows an exploded view of the glue cartridge heater presented in  FIG. 15 ; 
           [0047]      FIG. 17  shows a detail of the glue cartridge receiving unit, illustrating the lateral spring system; 
           [0048]      FIG. 18  shows an exploded view, illustrating the mounting of the lateral spring system presented in  FIG. 17 ; 
           [0049]      FIG. 19  shows the bookbinding machine; 
           [0050]      FIGS. 20 and 21  show cross sections of the glue spreading roller casing; 
           [0051]      FIG. 22  shows a bottom view of the glue spreading roller casing; 
           [0052]      FIG. 23  shows a top view of the glue spreading roller casing; and 
           [0053]      FIG. 24  shows a longitudinal section of the glue spreading roller casing. 
       
    
    
       [0054]    The same reference numbers refer to same technical features in all drawings. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0055]      FIG. 1  shows glue cartridge  1  and cover of the glue cartridge  7   b .  FIG. 2  shows an exploded view of glue cartridge  1 . 
         [0056]    Glue cartridge  1  comprises glue tank  2 . Glue tank  2  may contain either PUR adhesive or EVA hotmelt (either one of them or both are referred to more generally by the term glue in the following). Glue cartridge  1  is either closed from the top or can be closed from the top. In other words, cover  7   b  can be either a fixed or a detachable part of glue cartridge  1 . If cover  7   b  is detachable, it can be equipped with knob  7   b  to facilitate detaching. 
         [0057]    In addition, glue cartridge  1  comprises glue spreading roller  7 . Glue spreading roller  7  is a part of shaft  3  which most advantageously has shaft surfaces for bearing support. The bearing support is implemented by means of bearings  8 . Material may have been removed from the surface of bearings  8  (e.g. by surface milling on the lower surface). This is utilized if the glue cartridge is being purged at the cleaning station. Slide bearings or cylinder liners are most advantageously used as bearings  8 . 
         [0058]    The surface of glue spreading roller  7  is toothed e.g. by means of grooving and/or by making other appropriate surface reliefs into it, for instance protrusions, or combinations of these. Bearings  8  are mounted tightly against the shaft surfaces of shaft  3  thus acting as seals. The wall thickness of bearings  8  is greater than the depth of the area between the adjacent teeth or projections of glue spreading roller  7 . Bearings  8  are set tightly against the ends of glue spreading roller  7  (i.e. the toothed part of shaft  3 ) on either side. 
         [0059]    The outside diameter of bearings  8 , the outside diameter of glue spreading roller  7  and the inner surface of glue spreading roller casing  80  (ref.  FIG. 20 ) have approximately the same diameter so that the resulting structure is so tight that glue cannot escape from glue tank  2  by mistake. 
         [0060]    However, the dimensioning allows glue spreading roller  7  to be rotated at the processing temperature of glue. 
         [0061]    The advantageous structure of glue spreading roller casing  80  is more evident from the drawings presented in  FIGS. 20 to 24 . 
         [0062]    Rotating device  9  is most advantageously implemented as protrusions in the other end of shaft  3  which enable the rotating of glue spreading roller  7  by means of shape-limiting transmission mechanism, together with the recesses remaining between the protrusions of torque converter  32 . 
         [0063]      FIGS. 2 to 6  show details of platform  4  of glue cartridge  1 , glue channel  12 , and tank bottom  15 . Platform  4  of glue cartridge  1  and glue tank  2  can be implemented in one piece or made of two or several separate parts. Platform  4  and glue tank  2  can be connected to each other for example by means of threads  13 ,  14 . 
         [0064]    Identification element  11  is attached to glue cartridge  1 ,  20 , for example with screw  10 . Bookbinding machine  100  identifies the type of glue cartridge on the basis of identification element  11  and sets the target temperature of the heater of glue cartridge  1 ,  20  and/or the power of the heater according to the type of the glue cartridge. 
         [0065]    Both edges of glue cartridge  1  are provided with extension  5 . There is a narrowed part  6  in the middle of extensions  5 . Extension  5  at the narrowed part  6 , i.e. in the middle, does not reach as far as it does at the ends. The narrowed part of upper part  6   b  is for example implemented by narrowing extension  5  on the top. Thanks to the narrowing of upper part  6   b  it is possible to implement stop face  5   b  with a small surface only. This reduces the conduction of heat from glue cartridge  1  into glue cartridge receiving unit  26 . 
         [0066]    Even if there is a narrowed part in the middle of extensions  5  in our exemplary embodiment, lateral narrowing  6  is only necessary on the side where the platform is supported by the arm. On the side of springs  64 , an air gap remains between shoulder  42  in arm  41   a  and platform  4  in any case. If narrowing  6  is made into platform  4  also on the side of springs  64 , it may have a negative effect if the fact is not taken into account that extension  5  momentarily presses spring  64  deeper during mounting than its position would be when the cartridge is mounted in place (i.e. to the bottom of narrowed part  6 ). This means that glue cartridge  1 ,  20  can also be implemented provided with unilateral narrowing  6  or without any narrowed parts because the effect caused by the narrowing can also be achieved by choosing an appropriate shape of jaw. 
         [0067]      FIG. 7  shows glue cartridge  1  equipped with a cover with mounting plate  16  being attached to it. To be able to lock glue cartridge  1  in place in the system by means of the locking latch, mounting plate  16  is mounted on glue cartridge  1  by means of fixing screws  18 . The face of glue cartridge  1  is provided with threaded holes  17  for this purpose. 
         [0068]    Mounting plate  16  of glue cartridge  1  has raising bushes  19  for forming an air gap between the plate part of mounting plate  16  of glue cartridge  1  and the face of glue cartridge  1 . The hole in raising bush  19  is used as an inlet for fixing screws  18  of the glue cartridge. This results in a small contact surface between the (hot) glue cartridge  1  and mounting plate  16  and in a reduced transfer of dissipated heat to mounting plate  16 . Mounting plate  16  has also holes for compression nuts  25 . Fixing screws  23  of setting device  21  are fixed to compression nuts  25 . 
         [0069]    As shown in  FIGS. 8 and 14 , glue cartridge receiving unit  26  comprises two arms  41   a ,  41   b . Moreover, glue cartridge receiving unit  26  comprises shoulder  42  in both arms. Shoulder  42  and the spacing between arms  41   a ,  41   b , as well as lower heaters  31  form the jaw. The width and height of platform  4  are dimensioned in such a way that glue cartridge  20  equipped with a fixing plate can be pushed into the jaw of receiving unit  26  by means of setting device  21  so that extensions  5  of platform  4  are positioned between lower heaters  31  and shoulders  42  on both sides. In this way, the jaw holds glue cartridge  1  in place in receiving unit  26  and prevents glue cartridge  1  from falling down. 
         [0070]    When setting device  21  is fixed to glue cartridge  20  equipped with mounting plate  16  by means of its fixing screws  23 , the cover trough in setting device  21  covers the heads of fixing screws  18  of mounting plate  16  of glue cartridge  20 . In this way, any accidental opening of fixing screws  18  of mounting plate  16  of glue cartridge  20  is prevented when fixing screws  23  of setting device  21  are meant to be opened in order to remove setting device  23 . 
         [0071]    If required, setting device  21  can be dimensioned in such a way that protective cover  115  or protective casing on bookbinding machine  100  cannot be closed while setting device  21  is attached. In other words, setting device  21  would in that case prevent the closing of protective cover  115  or protective casing. 
         [0072]    Glue cartridge receiving unit  26  is attached to bookbinding machine  100  ( FIG. 19 ). 
         [0073]    Arms  41   a ,  41   b  are attached to the back of receiving unit  26  by means of fasteners, such as screws, most advantageously through the inlets made into the back. 
         [0074]    As shown in  FIGS. 9 to 12 , glue cartridge  1 ,  20  can be attached to glue cartridge receiving unit  26  by means of locking latch  28  which can be turned in relation to bearing journal  29 . Locking groove  30  of the locking latch is positioned on mounting plate  24  and prevents any unintentional removal of glue cartridge  1 ,  20 . 
         [0075]    After mounting glue cartridge  1 ,  20  in place, setting device  21  can be removed. For this purpose, fixing screws  23  are loosened and setting device  21  is pulled out. Thanks to the remaining air gap between mounting plate  16  and setting device  21  (ref. raising bushes  19 ) it is possible to reduce the heating of fixing screws  23  and setting device  21 . The removal of setting device  21  can be carried out safely by means of handle  27 . 
         [0076]    Locking latch  28  opens when setting device  21  is attached to glue cartridge  20  equipped with mounting plate  16  by means of fixing screws  23 . Glue cartridge  1  can then be detached by pulling out handle  26  in setting device  21 . When glue cartridge  20  equipped with mounting plate  16  is removed from receiving unit  26 , locking latch  28  settles due to or assisted by gravity (by means of gravitational force) to its lower position against limit stop  67  (in the drawing shown in  FIG. 12 , limit stop  67  is the head of an Allen screw, and the Allen screw is screwed in the left arm  41   a ). The rear part of locking latch  28  is hinged, and a hinge bushing screwed on the left arm  41   a  is used as bearing journal  29 . 
         [0077]    Glue cartridge receiving unit  26  comprises converter  32  which has a traction element (most advantageously a gear or a sprocket, not shown in  FIG. 8 ) and a formed part which are permanently attached to each other through the opening of the axle system in such a way that the traction element can be accessed from outside the receiving unit  26 . 
         [0078]      FIG. 13  illustrates the structure of lower heater  31  in more detail. Lower heater  31  has electric cables  35  underneath guard plate  39  of the switch room. One electric cable  35  is used for applying the voltage to the heating resistor installed inside the heater body and the excess heat protection connected in series to it. The other electric cable, for its part, is used for conducting electricity to the temperature sensor attached to the heater body. 
         [0079]    Located below lower heater  31  are springs  36  which are attached to lower heater  31  by means of screws  37 . Springs  36  are provided with loop  38  at the lower end. Lower heater  31  also has through holes  40  for the clamping tool. 
         [0080]    Fixing screws  43  are initially fastened to mounting holes  44  (ref.  FIG. 14 ). After that, loops  38  are pushed into fixing screws  43  and fixing screws  43  are tightened via through-hole  40  of the tool. If necessary, screws  37  can be tightened by means of the through holes  45  of the tool while lower heater  31  is mounted in place. 
         [0081]    Glue cartridge receiving unit  26  is thus equipped with lower heaters  31 , with springs  36  mounted below them for supporting lower heaters  31 . Springs  36  also yield, in this way allowing for the downward and upward movement of lower heaters  31 . Springs  36  are most advantageously dimensioned in such a way that they support lower heaters  31  at a level which allows for a gap which is smaller than or equal to the thickness of extension  5  of glue cartridge  1  to remain in arm  41   a ,  41   b , between lower heater  31  and shoulder  42  of arm  41   a ,  41   b.    
         [0082]    The upper edge in front of lower heater  31  has been bevelled so that glue cartridge  1 ,  20  can be easily pushed into place. The front edge of shoulder  42  of arm  41   a ,  41   b  has also been beveled to ease the mounting of glue cartridge  1 ,  20 . When glue cartridge  1 ,  20  has been mounted in place in the receiving unit, the top surfaces of lower heaters  31  are pressed against the bottom surface of glue cartridge  1 ,  20  by means of springs  36 , and springs  36  lift extensions  5  of the glue cartridge toward the bottom surfaces of shoulders  42  of arms  41   a ,  41   b  of the top surface. To reduce the heat conduction, however, only stop faces  5   b  of the upper side make a contact with shoulders  42 . 
         [0083]      FIGS. 17 and 18  illustrate the implementation of the lateral spring system of glue cartridge receiving unit  26 . The left arm  41   a  has springs  64 . Springs  64  are fastened to mounting holes  66  by means of screws  65 . 
         [0084]    Springs  64  in the left arm  41   a  of glue cartridge receiving unit  26  yield when the glue cartridge is pushed into place in receiving unit  26 . These springs  64  also press glue cartridge  1 ,  20  against the right arm  41   b . One of the springs  46  is most advantageously mounted from the front and two are mounted from inside in the left arm  41   a.    
         [0085]    As described above, the jaw of glue cartridge receiving unit  26  is self-adjusting both vertically and horizontally. It is clear that the jaw must not necessarily be self-adjusting or adjustable both vertically and horizontally but, in principle, even one of the two may suffice. 
         [0086]    In view of ensuring the heat conduction, the fact that the jaw is vertically self-adjusting or adjustable is important. Both a vertically self-adjusting jaw and a horizontally self-adjusting jaw have an effect on the mutual functioning of torque converter  32  and rotating device  9 . 
         [0087]    The easiest way of implementing a vertically self-adjusting jaw is by means of springs. As an alternative to the vertically self-adjusting jaw, the jaw can be implemented as a vertically adjustable jaw, for example by shifting (e.g. by turning at least one set screw) lower heaters  31  downward at first so that glue cartridge  1  can be pushed into place in the glue cartridge receiving unit and, after this, by shifting (e.g. by turning at least one set screw) lower heaters  31  upward so that lower heaters  31  are tightly against platform  4  of glue cartridge  1 . 
         [0088]    Likewise, the easiest way of implementing a horizontally self-adjusting jaw is by means of springs  64 . As an alternative to the horizontally self-adjusting jaw, the jaw can be implemented as a horizontally adjustable jaw, for example by shifting the glue cartridge  1  laterally toward one of the arms  41   a ,  41   b  (e.g. by turning at least one set screw). 
         [0089]    As shown in  FIGS. 8 and 12 , glue cartridge receiving unit  26  is equipped with side heater  33 . Side heater  33  is preferably spring-loaded (ref.  FIGS. 12 and 15 ). An exploded view of side heater  33  is shown in  FIG. 16 . 
         [0090]    Side heater  33  is preferably implemented as a half-open jacket heater. This enables to push the glue cartridge into place.  FIGS. 12 and 15  illustrate the implementation of glue cartridge receiving unit  26  with regard to the attachment of side heater  33 .  FIG. 16  illustrates the design of side heater  33 . 
         [0091]    Side heater  33  is resiliently mounted on rear part  50 . Side heater  33  has mounting holes  34  and rear part  50  has mounting holes  49  for this purpose. The springs are pressed between side heater  33  and rear part  50  by means of shoulder screws  48  which are fastened to mounting holes  34  from behind the rear part  50 . 
         [0092]    Side heater  33  comprises heater body  57  which is equipped with heater element  54  and temperature sensor  56 . To prevent the heating of rear part  50 , thermal insulation material  58  is attached to the back of body  57  underneath jacket  59 . To prevent the loss of heat, thermal insulation material  53  is attached under jacket  51  at the flanks and on top of body  57 . 
         [0093]      FIG. 19  shows bookbinding machine  100 . The operation of bookbinding machine  100  is started by putting glue cartridge  1 ,  20  into place in gluing unit  26  and by closing protective cover  115 . Plug  116  in cable  107  is connected to the mains. After that, current switch  106  in control panel  108  is turned from the position OFF to the position ON. The current flowing from cable  107  heats up the resistors in the heating units (lower heaters  31  and side heater  33 ) and melts the glue in glue tank  1 . 
         [0094]    Bookbinding machine  100  is equipped with operating handle  114 . The operating principle of operating handle  114  and the operating mechanism of the bookbinding machine connected to it have been presented in more detail in the patent EP 1 478 519 B1. 
         [0095]    The mode of operation of bookbinding machine  100  is shown in more detail in the video http://fastbind.com/images/stories/videos/elite_soft_cover. wmv 
         [0096]    Book cover  121  is placed into bookbinding machine  100  and bundle  120  of sheets to be bound on top of it. 
         [0097]    The side edge of bundle  120  is aligned against aligning stop  109 . After that, bundle  100  is locked in place by turning operating handle  105 , whereby mobile press bar  102  presses bundle  120  against turntable  112 . After that, press bar  102  is locked in relation to turntable  112  by continuing to turn operating handle  105 , whereby bundle  120  also keeps its position in relation to turntable  112 . 
         [0098]    After that, operating handle  103  is turned in the direction of arrow b. Due to this, turntable  112  turns to a position in which spine edge  124  of bundle  120  is on the route of the backwards and forwards movable (arrow c) glue cartridge receiving unit  26  and especially of glue spreading roller  7  located there. Glue cartridge receiving unit  26  can be moved together with glue spreading unit  111  along linear guide  113 . The movement is preferably carried out using a guiding tool, such as knob  114 . The system also comprises a transmission device, for example a tooth chain, which rotates the traction element, preferably in a shape-limiting manner. The transmission device forces traction element  1  to rotate every time receiving unit  26  of glue cartridge  26  is pushed in either direction along linear guide  113 . 
         [0099]    The rotating traction element rotates the formed part which rotates glue spreading roller  7  as described above, whereby glue spreading roller  7  takes glue out of glue tank  2  and applies it to spine edge  124  of bundle  120 . When the traction element is standing still, i.e. glue spreading roller  7  does not rotate, the shape of glue spreading roller  7  prevents glue from escaping from glue tank  2 . 
         [0100]    In case any glue remaining at the lower edge of glue spreading roller  7  should drip, bookbinding machine  100  is also equipped with drip tray  110  for the glue dripping or possibly leaking from glue spreading roller  7 . 
         [0101]    When spine edge  124  of bundle  120  is glued, operating handle  103  is turned in the direction of arrow a, whereby turntable  112  and bundle  120  rotate against cover  121 . By pressing operating handle  103  further in the direction of arrow a, the mechanism in bookbinding machine  100  presses the edge of cover  121  against bundle bound tight on the edge on the side of spine edge  124  as described in patent 1 478 519 B1. 
         [0102]    After that, the finished book is released by turning operating handle  105  and bookbinding machine  100  can be used for binding the next bundle of sheets together and to the cover. 
         [0103]    The improvement of bookbinding machine  100  shown in  FIG. 19  is based on the fact that the mounting of glue cartridges  1 ,  20  in system  26  is easier thanks to the self-adjusting or adjustable jaw. The dimensional tolerances of glue cartridges  1 ,  20  can also be greater. Thanks to the self-adjusting feature or adjustability, it is also easier to avoid the problems possibly caused by the different degree of thermal expansion in different pieces, such as glue cartridge  1 ,  20  getting blocked in system  26 . 
         [0104]    Glue cartridge  1 ,  20  is mounted or can be mounted in glue cartridge receiving unit  26 . This enables to change the glue type used on the fly (while the operation is running) or with a short break at the most. Glue cartridge  1 ,  20  can be exchanged even if bundle  120  to be bound is in place in bookbinding machine  100 . 
         [0105]    During the spreading of glue, glue spreading roller  7  supplies glue tank  2  with the amount of replacing air corresponding to the amount of glue taken by glue spreading roller  7  from glue tank  2  for spine edge  124  of bundle  120  to be bound, or to the amount of glue that otherwise escapes from glue spreading roller  7 , for example by dripping. In this way, no under-pressure is developed in glue tank  2  that would make it more difficult to get the glue out of glue tank  2 . The amount of replacing air most advantageously corresponds to the amount of glue that has been transferred to spine edge  124  of bundle  120  and has dripped onto drip tray  110 . 
         [0106]    Glue cartridge  1 ,  20  can also be heated in advance until it is warm (for example even up to or almost to processing temperature, or, accordingly, for example to midway between the ambient temperature and the processing temperature of glue, or to any other point between them) at a preheating station connected to bookbinding machine  100  or located outside it. Such a preheating station has most advantageously a heating arrangement corresponding to side heater  33  and/or to lower heaters  31 , as well as a receiving unit corresponding to glue cartridge receiving unit  26 . Thanks to preheating, glue cartridge  1 ,  20  is available faster, and the use of bookbinding machine  100  can be continued uninterruptedly. In the method for accelerating the adhesive binding, glue tank  2  of glue cartridge  1 ,  20  is heated before mounting glue cartridge  1 ,  20  in bookbinding machine  100 . 
         [0107]    All parts of glue cartridge  1 ,  20 , except for bearings  8 , can be made of aluminum. Shaft  3  and glue spreading roller  7  are most advantageously implemented as an extruded aluminum profile. In this case, the extrusion is implemented on the profile of glue spreading roller  7  and, for shaft surface  3 , material is removed from the profile by turning on a lathe (removal of teeth or protrusions, in addition to which shaft  3  is made thinner on the outside part of glue spreading roller  7 ). 
         [0108]    Glue cartridge  1 ,  20  is removed from bookbinding machine  100  after use. If the part to be removed is hot, the removal can be carried out by means of separate setting device  21 . 
         [0109]    The invention should not be understood as being limited only to the attached patent claims, but it should be understood to include all their legal equivalents. 
         [0110]    Especially the shape and amount of shoulders in glue cartridge receiving unit  26  may vary. The number and execution type of arms  41   a ,  41   b  may also vary. The jaw can also be implemented in many different ways. 
       REFERENCE NUMBERS USED 
       [0000]    
       
           1  glue cartridge 
           2  glue tank 
           3  shaft 
           4  platform 
           5  extension 
           5   b  stop face of upper side 
           6  narrowed part 
           6   b  narrowing of upper side 
           7  glue spreading roller 
           7   a  knob 
           7   b  cover 
           8  bearing 
           9  rotating device 
           10  screw 
           11  identification element 
           12  glue channel 
           13  thread 
           14  thread 
           15  bottom of glue tank 
           16  mounting plate 
           17  threaded hole 
           18  fixing screw 
           19  raising bush 
           20  glue cartridge equipped with mounting plate 
           21  setting device 
           22  plate 
           23  fixig screw 
           24  mounting plate 
           25  compression nut 
           26  glue cartridge receiving unit (system) 
           27  handle 
           28  locking latch 
           29  bearing journal 
           30  locking groove 
           31  lower heater 
           32  torque converter 
           33  side heater 
           34  mounting hole 
           35  electric cable 
           36  spring 
           37  fixing screw 
           38  suspension loop 
           39  guard plate of switch room 
           40  through hole of mounting tool 
           41   a  left arm 
           41   b  right arm 
           42  shoulder 
           43  fixing screw 
           44  mounting hole 
           45  through hole of tool 
           47  spring 
           48  shoulder screw 
           49  mounting hole 
           50  rear part 
           51  jacket 
           52  screw 
           53  thermal insulation material 
           54  heating element 
           55  screw 
           56  temperature sensor 
           57  heater body 
           58  thermal insulation material 
           59  jacket 
           60  screw 
           61 ,  62 ,  63  fasteners 
           64  spring 
           65  screw 
           66  mounting hole 
           67  limit stop 
           68  release plate 
           80  casing of glue spreading roller 
           83  face 
           84  bevel 
           85  bevel 
           86  flank 
           100  bookbinding machine 
           102  press bar 
           103  operating handle 
           105  operating handle 
           106  current switch 
           107  cable 
           108  control panel 
           109  aligning stop 
           110  drip tray 
           111  glue spreading unit 
           112  turntable 
           113  linear guide 
           114  knob 
           115  protective cover 
           116  plug 
           120  bundle of sheets to be bound 
           121  book cover 
           124  spine edge 
       
     
         [0204]    Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention, which is not to be limited except by the allowed claims and their legal equivalents.