Abstract:
A glue valve arrangement having a controllable, in particular electromagnetically operated metering member for the delivery of glue, having a main body with glue duct leading to the metering member, having a tubular glue line, with which glue originating from a separate glue source can be fed to the glue duct, having a rotary feedthrough, detachably fastened to the main body, for the articulated connection of the tubular glue line to the main body, and having a filter for the filtering of the glue. The invention is characterized in that the filter is assigned to the rotary feedthrough.

Description:
STATEMENT OF RELATED APPLICATIONS 
       [0001]    This application is the US National Phase of International Application No. PCT/EP2015/002458 having an International Filing Date of 7 Dec. 2015, which claims priority on German Patent Application No. 10 2014 018 969.4 having a filing date of 22 Dec. 2014. 
     
    
     BACKGROUND OF THE INVENTION 
     Technical Field 
       [0002]    The present invention relates to a glue valve arrangement comprising a glue valve having a controllable, in particular electromagnetically operated metering member for the delivery of glue, in particular of hot glue, comprising a main body with glue duct leading to the metering member, comprising a separate tubular glue line, which runs in particular outside the main body and with which glue originating from a separate glue source can be fed to the glue duct, comprising a rotary feedthrough, fastened to the main body, for the articulated connection of the tubular glue line to the main body, and comprising a filter for the filtering of the glue. The invention further relates to a rotary feedthrough for a glue valve arrangement of this type. 
       Prior Art 
       [0003]    Glue valve arrangements of this type, comprising controllable metering or closure members, or comprising one or more glue valves having such members, have long been known. In the cigarette industry, in particular, glue valve arrangements of this type are widely operated with hot glue. In this case, a wide variety of components of the glue valve arrangement are purposefully heated and kept at a defined temperature, in order to be able to guarantee the delivery of defined glue portion sizes throughout the operation. For the viscosity, and ultimately also the size of the respective glue portion which leaves the respective glue valve of the glue valve arrangement during the respective period of opening of the metering member, are dependent on the glue temperature. In order to prevent the metering member from being blocked by impurities in the glue, or the like, the glue is filtered through a filter which in the prior art is inserted in the main body of the glue valve arrangement or of the respective glue valve. In this context, it is inter alia disadvantageous that a changing of the filter is possible only in the liquid, hot state of the glue. For the worker entrusted with changing the filter, there is an acute risk of burning. In addition, appropriate bores must be made in the generally solid main body in order to be able to place the filter suitably in position. Not least, the filter has a certain spatial requirement which prevents the appropriate main bodies from being able to be built more compactly. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    The object of the present invention is to refine a glue valve arrangement of the type stated in the introduction, and a rotary feedthrough for this same. 
         [0005]    This object is achieved by a glue valve arrangement comprising a controllable, in particular electromagnetically operated metering member for the delivery of glue, comprising a main body with glue duct leading to the metering member, comprising a tubular glue line, with which glue originating from a separate glue source can be fed to the glue duct, comprising a rotary feedthrough, detachably fastened to the main body, for the articulated connection of the tubular glue line to the main body, and comprising a filter for the filtering of the glue, characterized in that the filter is assigned to the rotary feedthrough ( 20 ). 
         [0006]    According to the invention, the filter of the glue valve arrangement is no longer housed in the main body of the valve arrangement, but rather the filter is assigned to the rotary feedthrough, which is arranged largely outside the main body and which establishes the articulated connection of the tubular glue line to the main body. This articulated connection enables relative movements between these components, for instance for maintenance or assembly purposes. By no longer housing the filter in the main body, but rather assigning it to the rotary feedthrough, a significantly more compact design of the main body is enabled. Furthermore, the filter can be changed more easily, and more safely for the user. The bores in the main bodies, which are difficult to produce and are necessary in the prior art and into which the filters are placed, can also be dispensed with. 
         [0007]    Preferredly, the filter of the rotary feedthrough is assigned to a filter receiving part of the rotary feedthrough, which filter receiving part is detachably connected—in particular via a screw joint—to the main body, and preferredly is screwed into a bore of this same, and is detachably connected to a pivot joint part, comprising a pivot joint, of the rotary feedthrough, preferably likewise via a screw joint. As a result of the detachable connection between filter receiving part and main body, on the one hand, and between filter receiving part and pivot joint part, on the other hand, a changing of the filter is particularly simple. For the entire filter receiving part can be straightforwardly replaced by a new filter receiving part with new filter. 
         [0008]    In a further configuration of the filter receiving part, this possesses an in particular central glue duct for the passage of the glue. In this glue duct sits the filter, for instance extending transversely to this glue duct over the entire cross section of this same, so that the glue, during passage through the glue duct, must flow through the filter. 
         [0009]    In a still further configuration of the filter receiving part or of the rotary feedthrough, the filter of the rotary feedthrough can be held in the glue duct by means of a pressing ring seated in an in particular central bore of the filter receiving part. Expediently, the central bore here preferredly forms the glue duct or is part thereof. 
         [0010]    For the simple installation or removal of the rotary feedthrough, it can be provided that the filter receiving part possesses an external thread, which is screwed into a fitting internal thread of the pivot joint part. 
         [0011]    As far as the pivot joint part of the rotary feedthrough is concerned, it can possess a first connector detachably connected to the filter receiving part, as well as a second connector rotatably mounted on the first connector. 
         [0012]    Preferably, the second connector of the pivot joint part is here detachably connected to the tubular glue line, in particular by a screw joint to a glue line connector of the tubular glue line. Hence the first and the second connector are twistable relative to each other, whereby the relative movement between tubular glue line, on the one hand, and main body of the valve arrangement, on the other hand, is enabled. Ultimately, the rotatable mounting of the second connector on the first connector is then a constituent part of the pivot joint of the pivot joint part. 
         [0013]    The pivot joint of the pivot joint part can in general possess just an individual (single-row) ball bearing. The relinquishment of a further, adjacent ball bearing enables a compact design. It can further be provided that the pivot joint possesses, in addition to the single-row ball bearing, also a slide bearing, in order to be able to reliably fully compensate all bending moments. 
         [0014]    Preferably, also an individual single-row four-point ball bearing can be used in order to be able to safely dispense with an additional slide bearing. This variant enables a still more compact design. 
         [0015]    The outer ring of one of the above-stated ball bearings is preferredly formed directly by the first connector, connected to the filter receiving part, of the pivot joint part, and the inner ring of this same by the second connector of the pivot joint part. For this purpose, appropriate circumferential recesses for the balls of the ball bearing can be made in the first connector or the second connector. 
         [0016]    The second connector of the pivot joint part of the rotary feedthrough is preferredly of angled configuration or configured as an angle piece and possesses an in particular central glue duct, which extends up to an end piece, facing the filter receiving part, of the second connector, which end piece sits rotatably mounted in a central bore of the first connector. The other end piece of the second connector, which points in the direction of the tubular glue line, would accordingly run at an angle, in particular perpendicular, to the end piece facing the filter receiving part. 
         [0017]    The aforementioned angularity of the second connector, or its configuration as an angle piece, then ensures the desired degree of freedom of the rotary feedthrough, or that the glue tube, together with the other end piece of the second connector, can be rotated or pivoted in a plane which runs at an angle, in particular perpendicular, to the rotational axis about which the end piece facing the filter receiving part—as a result of its rotatable mounting in the central bore of the first connector—can rotate. 
         [0018]    Alternatively, it can also be provided, however, that the second connector is of straight or non-angular configuration. The two end pieces of the second connector would accordingly run not at an angle to each other, but along a common straight axis. 
         [0019]    As far as the glue duct of the second connector is concerned, it preferredly opens out into the glue duct of the filter receiving part of the rotary feedthrough, wherein, for the (radial) sealing, that end piece of the second connector which embraces the appropriate glue duct end bears sealingly against one side of an elastic (ring) seal, and the filter receiving part, in particular the pressing ring of the filter receiving part, bears sealingly against the other side of the elastic seal. 
         [0020]    In a further configuration of the invention, it is provided that to the filter receiving part of the rotary feedthrough is fastened an elastic (ring) seal, which, when the filter receiving part is fastened to the main body of the glue valve unit, ensures a glue-tight sealing between main body and filter receiving part. 
         [0021]    The object of the present invention is also achieved by a rotary feedthrough for the articulated connection of a tubular glue line to a main body of a glue valve arrangement, characterized in that the rotary feedthrough possesses a filter for the filtering of glue flowing through the rotary feedthrough. Accordingly, such a rotary feedthrough has a filter for the filtering of the glue flowing through the rotary feedthrough. The further possible configuration of such a rotary feedthrough has already been comprehensively described above in connection with the whole of the glue valve arrangement. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    Further features of the present invention emerge from the appended patent claims, the following description of preferred illustrative embodiments of the invention, and from the appended drawings, in which: 
           [0023]      FIG. 1  shows a top view of a glue valve arrangement comprising a plurality of individual valves, along with rotary feedthrough and tubular glue line, 
           [0024]      FIG. 2  shows a cross section through the rotary feedthrough of the glue valve arrangement from  FIG. 1  in operation-ready, assembled state, and 
           [0025]      FIG. 3  shows a cross section, analogous to  FIG. 2 , through an embodiment of the rotary feedthrough, yet with rotary feedthrough dismantled into two individual components, namely into a filter receiving part and into a pivot joint part. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0026]    In  FIG. 1 , a glue valve arrangement  10  is represented schematically. It comprises in this case a plurality of individual modules  11 . A plurality of, in the present case two of these modules  11  respectively possess a glue valve  14 . A glue valve arrangement of this type is described in DE 10 2014 001 897.0, to the content of which reference is extensively made. According to the invention, the glue valve arrangement  10  can also, of course, be of non-modular configuration and comprise, for instance, only one glue valve. 
         [0027]    In the shown illustrative embodiment, the valve arrangement  10  serves to apply glue, namely, in the present case, hot glue, to surfaces of blanks used in the manufacture of cigarette packs and made of paper, foil or the like. 
         [0028]    With the glue valves  14  of the valve arrangement  10 , respectively individual (small) glue portions are applied to the respective blank  12 . Normally, for this purpose, the respective blank  12  is moved relative to the valve arrangement  10 , in particular transversely to the longitudinal extent of this same. In this way, the valve arrangement  10  can be fixedly positioned, for instance, in a horizontal plane, and the blanks  12  to be provided with the glue are conveyed, in a horizontal plane parallel thereto beneath the valve arrangement  10 , along under this same (arrow direction in  FIG. 1 ). Accordingly, individual parallel glue traces, which are spaced apart perpendicular to the direction of feed of the respective blank  12  or in the direction of the longitudinal extent of the valve arrangement  10 , are respectively formed from respectively individual glue portions  13 . 
         [0029]    The individual modules  11  are arranged, in the longitudinal extent of the valve arrangement  10 , consecutively in a common line. They are in part differently constructed or have different functions. Two of the individual modules shown in  FIG. 1  respectively have a glue valve  14 , with metering opening (not shown) integrated in this same and with appropriate controllable metering member (likewise not represented). 
         [0030]    The glue valves  14  are known per se and can be actuated, for instance, electromagnetically. 
         [0031]    During operation, the metering or closure member is moved to and fro, in particular cyclically, between an opening position, in which glue can pass out of the glue valve  14 , and a closing position, in which the glue cannot pass out. 
         [0032]    The opening force necessary for an opening movement can be generated, for instance in known manner against the resistance of a return member, by the magnetic force of a controllable electromagnet. After the magnetic field has been switched off or, in general, after the opening or magnetic force has been sufficiently reduced, the closing force necessary for a closing movement can be applied by the return member, for instance by a spring or by mutually repelling permanent magnets. 
         [0033]    An appropriate electronic control system, to which the respective glue valve  14  is connected, then ensures the necessary impulses for the opening and closing of the glue valve  14 . 
         [0034]    Each of the individual modules  11  possesses a, in the present case, substantially solid main body  15 . However, such a main body can also be configured in the manner of a housing, for instance. 
         [0035]    In the main body  15  respectively runs at least one glue duct, or the individual glue ducts of the main body  15  are connected to one another such that hot glue, which is fed to the valve arrangement  10  via a tubular, flexible glue line/tube  16  running outside the main body  15 , can respectively be conducted to the individual glue valves  14 , and within these same to the individual metering members of the glue valves  14 . 
         [0036]    In  FIG. 1  is additionally shown a tube  18  of the valve arrangement  10 , in the inside of which run leads which extend from the electronic control system for the individual modules  11  or glue valves  14  toward the modules  11 . 
         [0037]    In a further tube  19  of the valve arrangement  10  run power supply lines, which originate from an appropriate voltage supply source and which end at heating members which are disposed in the main bodies  15  and which serve to heat the main bodies  15  and, in particular, the glue valves  14 . 
         [0038]    Particularly important is now a rotary feedthrough  20  of the valve arrangement  10 , via which the heated glue line  16  is articulately, namely rotatably, connected to the main body  15 —in the present case of an, in  FIG. 1 , outer—individual module  11 . 
         [0039]    The rotary feedthrough  20  is on the one hand detachably connected to the main body  15 , on the other hand detachably connected to a connector  21  connected to the glue line  16 . 
         [0040]    The rotary feedthrough  20  is here arranged, in a glue-conducting manner, between the glue line  16  and the main body  15 . In other words, the glue flows out of the glue line  16  through the rotary feedthrough  20  to the main body  15 . 
         [0041]    The rotary feedthrough  20  is configured such that the glue line  16  can be pivoted relative to the main body  15 , in the present case in a plane running parallel to that outer side of the main body  15  to which the rotary feedthrough  20  is fastened. Of course, other rotation or pivot planes can also be provided. 
         [0042]    The rotary feedthrough  20  possesses a central glue duct  22 , which opens out into the glue duct  17  (shown in  FIG. 2 ) of the main body  15 . The glue fed via the glue duct  17  is distributed inside the individual modules  11 , in particular in the appropriate main bodies  15 , to the individual glue valves  14 , if need be via further connecting glue ducts. 
         [0043]    The glue duct  22  of the rotary feedthrough  20  is composed of individual part-sections  22 . 1  and  22 . 2 . 
         [0044]    The glue duct section  22 . 1  runs within a pivot joint part  23  of the rotary feedthrough  20 . 
         [0045]    The pivot joint part  23  is in the present case composed of a first connector  24  and a second connector  25 . 
         [0046]    The second connector  25  of the pivot joint part  23  of the rotary feedthrough  20  is at one end, namely at a first end piece  26  facing the glue line  16 , detachably connected to, in the present case screwed to, the connector  21  of the glue line  16 . 
         [0047]    The other end of the second connector  25 , namely a second end piece  27  of this same, runs at an angle, in the present case perpendicular, to the first end piece  26 . 
         [0048]    Furthermore, the second end piece  27  is mounted rotatably on the first connector  24 . More specifically, it engages in a central bore  40  of the first connector  24  and is there, in the embodiment shown in  FIG. 2 , rotatably mounted by means of a single-row ball bearing  29  as well as a slide bearing  30 . 
         [0049]    The radial inner side of the first connector  24  and the radial outer side of the second connector  25 , more specifically of the second end piece  27  of the second connector  25 , here form the outer ring or the inner ring of the ball bearing  29 . To put it more precisely, appropriate annular recesses are recessed into the appropriate faces of the first connector  24  or of the second connector  25 . 
         [0050]    The ball bearing  29  and the slide bearing  30  form together with the first connector  24  and the second connector  25 , or the second end piece  27  of the second connector  25 , ultimately a pivot joint  31  of the pivot joint part  23 . 
         [0051]    Detachably connected to the pivot joint part  23 , more specifically to the first connector  24 , is a filter receiving part  32  of the rotary feedthrough  20 . In the present case, the filter receiving part  32  is detachably screwed to the pivot joint part  23  or the first connector  24 . 
         [0052]    The filter receiving part  32  possesses a central bore  33 , which ultimately forms the further glue duct section  22 . 2  of the rotary feedthrough  20 . The glue duct section  22 . 1  here opens out, in the direction of flow of the glue, into the glue duct section  22 . 2 . The bore  33  of the filter receiving part  32  widens in the direction of that end of the filter receiving part  32   e  which is connected to the pivot joint part  23 . 
         [0053]    In the bore  33 , in the present case in a widened section thereof which forms a receiving region  35  of the filter receiving part  32 , is arranged a filter  34 , which is known per se, for the filtering of the glue flowing through said filter. 
         [0054]    The filter  34  extends transversely to the bore  33  or to the glue duct section  22 . 2 . The receiving region  35  is in the present case of (hollow-)cylindrical configuration. The filter  34  extends over the whole of the cross section of the glue duct section  22 . 2 . 
         [0055]    The filter  34  is held in its position by a pressing ring  36 , which is pressed into the receiving region  35  with an interference fit. 
         [0056]    For the sealing between the second end piece  27  of the second connector  25  of the pivot joint part  23 , on the one hand, and the filter receiving part  32 . on the other hand, a seal  37  is provided, in the present case an elastic ring seal. Bearing sealingly against the ring seal  37  is, on the one hand, a free end face of the second end piece  27  and, on the other hand, a free end face of the pressing ring  36 . 
         [0057]    On the side facing the main body  15 , the filter receiving part  32  is connected to this main body  15  by means of a screw joint. In the present case, an end piece  41  of the filter receiving part  32  is screwed into a fitting threaded bore in the main body  15 . 
         [0058]    For the sealing between the filter receiving part  32  and the main body  15 , an elastic (ring) seal  38  is arranged between these components. The seal  38  is here fastened to the filter receiving part  32 . 
         [0059]    The shown design of the rotary feedthrough  20  with components detachably connected to each other, in particular the filter receiving part  32 , with filter  34 , detachably connected to the main body  15 , on the one hand, and the pivot joint part  23 , on the other hand, offers inter alia the particular advantage of being able to exchange the filter  34  easily whenever required. 
         [0060]    In this event, the entire filter receiving part  32 , with filter  34  accordingly in need of exchange, can be straightforwardly replaced by a new filter receiving part  32  with new filter  34 . For this, only the connection or screw joint between the filter receiving part  32  and the main body  15  must be released, as well as the connection between the filter receiving part  32  and the pivot joint part  23 . After this, the new filter receiving part  32  can then be connected or screwed to the aforementioned components. 
         [0061]    In  FIG. 3 , the removability of the aforementioned components is indicated on the basis of a rotary feedthrough  20  comprising two alternative embodiments of the pivot joint part  23 . 
         [0062]    Both alternatives of the pivot joint part  23  of  FIG. 3 , visually separated from each other by a dash-dot double line, differ from the pivot joint part  23  of  FIG. 2  on the one hand by virtue of the fact that, in the pivot joint part  23  of  FIG. 3 , the second connector  25  is not configured as an angle piece, but as a straight component configured, in particular, symmetrically to a longitudinal center axis. 
         [0063]    Hence, the first and the second end piece  26 ,  27  of the second connector  25  are arranged one behind the other along a common straight line axis. For this reason, the rotational axis about which the tubular glue line  16  can be rotated by the rotatable mounting of the second connector  25  on the first connector  24  coincides with the rotational axis about which the end piece  27  of the second connector  25  can be rotated. 
         [0064]    That embodiment of the pivot joint part  23  which is represented beneath the dash-dot double line differs from the solution from  FIG. 2 , moreover, by virtue of the fact that, instead of the ball bearing  29  and the slide bearing  30 , a four-point ball bearing  39  is used. 
         [0065]    Through the use of the four-point ball bearing  39 , the first connector  24 , and consequently also the second connector  25 , can be built shorter, while at the same time maintaining the required absorption of the bending moments, since the rotary mounting, by virtue of just a single four-point ball bearing, occupies less space than the rotary mounting using a combination of normal single-row ball bearing and slide bearing. 
         [0066]    Of course, the four-point ball bearing can also be used in the embodiment of the pivot joint part  23  of  FIG. 2 . 
       REFERENCE SYMBOL LIST 
       [0000]    
       
           10  glue valve arrangement 
           11  individual module 
           12  blank 
           13  glue portion 
           14  valve unit 
           15  main body 
           16  glue line 
           17  glue duct 
           18  tube 
           19  tube 
           20  rotary feedthrough 
           21  connector 
           22  glue duct 
           22 . 1  part-section 
           22 . 2  part-section 
           23  pivot joint part 
           24  first connector 
           25  second connector 
           26  first end piece 
           27  second end piece 
           29  ball bearing 
           30  slide bearing 
           31  pivot joint 
           32  filter receiving part 
           33  bore 
           34  filter 
           35  receiving region 
           36  pressing ring 
           37  seal 
           38  (ring) seal 
           39  four-point ball bearing 
           40  bore 
           41  end piece