Abstract:
A unit for feeding filters to a filter assembly machine, wherein at least one deflecting device receives a respective succession of filter portions in an axial direction, and feeds the filter portions to the filter assembly machine in a transverse direction crosswise to the filter portions; the deflecting device being defined by a fixed frame supporting an input and an output, and by an extractable box fitted movably to the fixed frame and supporting a first conveying device for conveying the filter portions in the axial direction, a second conveying device for conveying the filter portions in the transverse direction, and a deflecting member for diverting the filter portions to the transverse direction.

Description:
This application claims the benefit of Italian Patent Application Serial No. BO2003A 000491, filed Aug. 8, 2003. 
   The present invention relates to a unit for feeding filters to a filter assembly machine. 
   More specifically, the present invention relates to a unit for feeding filters to a filter assembly machine, the unit receiving at least one succession of filter portions travelling in a first axial direction, and feeding the filter portions to the filter assembly machine in a second direction crosswise to the filter portions; and the unit being of the type comprising a deflecting device having an input for receiving the succession of filter portions travelling in the first direction, and an output for the filter portions travelling in the second direction, and feed means for feeding the succession of filter portions to the input in the first direction. 
   BACKGROUND OF THE INVENTION 
   In a known unit of the type described above, the sharp change in the feed direction of the filter portions sometimes results in jams, the frequency of which is in direct proportion to the operating capacity of the filter assembly machine connected to the unit. Jams of this sort must obviously be cleared immediately, by not only blocking the filter feed unit, but also, in a relatively short space of time, the filter assembly machine connected to the unit. 
   On the other hand, known units of the type described are normally so complex in design as to make fast manual intervention by an operator from the outside difficult, so that jamming invariably involves considerable downtime and, very often, stoppage of the relative filter assembly machines. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide a filter feed unit designed to eliminate the aforementioned drawbacks and permit relatively fast servicing. 
   According to the present invention, there is provided a unit for feeding filters to a filter assembly machine, as claimed in Claim  1  and, preferably, in any one of the following Claims depending directly or indirectly on Claim  1 . 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A number of non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which: 
       FIG. 1  shows a schematic front view of a first preferred embodiment of the filter feed unit according to the present invention; 
       FIG. 2  shows a schematic, larger-scale plan view of a detail of  FIG. 1 ; 
       FIGS. 3 ,  4  and  5  show, with parts removed for clarity, larger-scale plan, side, and underside views respectively of a detail of  FIG. 2  in an open position; 
       FIGS. 6 and 7  show, with parts removed for clarity, larger-scale side and front views respectively of the  FIG. 3-5  detail in a closed operating position; 
       FIG. 8  shows a section along line IIX—IIX in  FIG. 7 ; 
       FIG. 9  shows a section along IX—IX in  FIG. 8 ; 
       FIGS. 10 ,  11  and  12  show larger-scale side, plan, and front operating diagrams respectively of the  FIG. 3-5  detail; 
       FIGS. 13 and 14  show the same views as, and a variation of,  FIGS. 3 and 5 ; 
       FIG. 15  shows a schematic front view of a second preferred embodiment of the filter feed unit according to the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Number  1  in  FIG. 1  indicates as a whole a unit for feeding filter portions  2  to an input hopper  3  of a filter assembly machine indicated as a whole by  4 . 
   Unit  1  is a modular unit, and comprises a number of identical, side by side modules  5 , each for receiving a relative succession of filter portions  2  travelling in an axial direction  6  ( FIG. 10 ), and for feeding filter portions  2  to filter assembly machine  4  in a transverse direction  7  ( FIG. 10 ) crosswise to filter portions  2 . 
   It should be pointed out that, here and hereinafter, directions  6  and  7  are relative as opposed to absolute, and relate to the position assumed by the longitudinal axis of each filter portion  2  at each point along its feed path along relative module  5 . 
   In the example shown, side by side modules  5  are four in number. In variations (not shown), however, a different number of modules  5 , and even only one module  5 , may be provided. 
   Each module  5  comprises a conduit  8  for pneumatically transporting filter portions  2  in axial direction  6 ; and a deflecting device  9 , which comprises an input  10 , through which filter portions  2  travel in direction  6  and which is connected to an output of conduit  8 , and an output  11  for feeding filter portions  2  to hopper  3  in transverse direction  7 . 
   As shown more clearly in  FIGS. 3 to 8 , each deflecting device  9  comprises a fixed, substantially L-shaped frame  12 , in turn comprising a hollow base body  13  in the form of a rectangular parallelepiped having a horizontal longitudinal axis parallel to axial direction  6  in which filter portions  2  travel through input  10 , and an end plate  14  extending upwards from one end of base body  13 . Base body  13  comprises a longitudinal lateral wall  15 ; a front wall  16  and rear wall  17  perpendicular to and projecting laterally from lateral wall  15 ; and an intermediate partition  18  parallel to walls  16  and  17  and projecting from lateral wall  15  to divide the space between walls  16  and  17  into an open-sided front chamber  19  and an open-side rear chamber  20 , of which front chamber  19  is closed at the bottom by a bottom wall  21 , while rear chamber  20  is also open at the bottom. 
   End plate  14  is coplanar and integral with rear wall  17 , and has a through hole  22  ( FIG. 8 ) having an axis  23  which, together with the longitudinal axis of base body  13 , defines a vertical plane P ( FIGS. 3 and 5 ) parallel to lateral wall  15 . Hole  22  houses a fitting  24  for connecting relative conduit  8  to frame  12 , and, together with fitting  24 , defines input  10  of deflecting device  9 . Front wall  16  supports two projecting rollers  25  which are located to the front of front wall  16 , have respective axes  26  of rotation parallel to axis  23 , located on opposite sides of plane P, and lying in a plane perpendicular to plane P, and support two endless belts  27  which, together with rollers  25 , define a conveyor  28  defining output  11  and driven by a motor  29 , which is fitted to frame  12  inside rear chamber  20 , and drives conveyor  28  via a transmission  30  fitted to frame  12  inside front chamber  19 . 
   Above relative frame  12 , each deflecting device  9  comprises a box  31 , a frame  32  of which is connected to frame  12  by a known, preferably recirculating-ball-type, guide-slide coupling  33 , which extends parallel to axis  23  and to direction  6 , is located laterally with respect to plane P, and comprises a guide  34  integral with the top ends of front wall  16  and intermediate partition  18  of frame  12 , and a slide  35  located beneath frame  32  and fitted in sliding manner to guide  34 . 
   Frame  32  comprises a longitudinal lateral wall  36 ; a front wall  37 ; and an intermediate partition  38  parallel to front wall  37  and projecting from lateral wall  36  to divide the space between front wall  37  and a rear end of lateral wall  36  into an open-sided front chamber  39  and an open-sided rear chamber  40 , of which front chamber  39  is open at the top and bottom, while rear chamber  40  is open at the top and closed at the bottom by a bottom wall  41 , to the underside surface of which is integrally connected a longitudinal rod defining slide  35 . 
   A top portion of rear chamber  40  houses a cup-shaped body  42  comprising a rear wall  43  perpendicular to axis  23  and located at the rear end of lateral wall  36 ; and a bottom wall  44  parallel to bottom wall  41  and located above axis  23 . 
   Chambers  39  and  40  house a conveying device  45  and a conveying device  46  respectively; conveying device  46  receives filter portions  2  successively from input  10 , and conveys them parallel to plane P in direction  6 ; and conveying device  45  receives filter portions  2  successively from conveying device  46 , and feeds them in direction  7  to output  11 . 
   Conveying device  46  comprises a slide plate  47  which is located inside rear chamber  40 , is suspended beneath bottom wall  44  of cup-shaped body  42 , and comprises a central longitudinal groove  48  coaxial with axis  23  and with a hole  49  ( FIG. 8 ) formed through intermediate partition  38  and for guiding filter portions  2  travelling in direction  6 . 
   Conveying device  46  also comprises two counter-rotating rollers  50  defined by grooved feed rollers, which are located between plate  47  and wall  44 , on opposite sides of plane P and at a break in groove  48 , and define between them a passage aligned with groove  48  and of a section approximately equal to but no larger than the section of filter portions  2 . Rollers  50  are fitted to respective shafts  51  perpendicular to and extending through bottom wall  44 , and which are fitted, inside cup-shaped body  42 , with respective pulleys  52 . 
   Conveying device  46  also comprises two counter-rotating rollers  53  defined by grooved accelerating rollers, which are located, downstream from rollers  50 , between plate  47  and wall  44 , on opposite sides of plane P and at a further break in groove  48 , and define between them a passage aligned with groove  48  and of a section approximately equal to but no larger than the section of filter portions  2 . Rollers  53  are fitted to respective shafts  54  perpendicular to and extending through bottom wall  44 , and which are fitted, inside cup-shaped body  42 , with respective pulleys  55  smaller in diameter than pulleys  52 . 
   Conveying device  46  also comprises an actuating device  56  housed inside cup-shaped body  42 , and which comprises a single belt  57  driven by a normally electric motor  58  carried by cup-shaped body  42 . Belt  57  is looped about pulleys  52  and pulleys  55  to impart to rollers  50  a peripheral speed V 1  substantially equal to the travelling speed of filter portions  2  through input  10 , and to rollers  53  a peripheral speed V 2  greater than V 1 . 
   Conveying device  45  comprises two side by side counter-rotating rollers  59 , at least one of which is connected directly to the output of a normally electric motor  60  carried by cup-shaped body  42 . Rollers  59  are mounted between front wall  37  and intermediate partition  38  of frame  32  of box  31  to rotate about respective axes  61  located on opposite sides of plane P, parallel to direction  6 , and defining a horizontal plane perpendicular to plane P. Rollers  59  are at least as long as a filter portion  2 , and define between them a channel  62 , which is a feed channel for feeding filter portions  2  to output  11  in direction  7 , is of minimum width approximately equal to but no greater than the diameter of a filter portion  2 , and comprises a wide input portion defining a seat  63  ( FIG. 12 ) aligned with hole  49  and for receiving a filter portion  2  travelling in direction  6  through hole  49 . 
   A deflecting member  64 , lying in plane P, is associated with conveying device  45 , and comprises an arm  65  having a curved underside rib  66  and hinged to the top of front wall  37  of frame  32  of box  31  to rotate, in plane P and about an axis perpendicular to plane P, between a substantially vertical raised rest position ( FIG. 8 ), and a lowered operating position in which arm  65  is positioned over and along seat  63 , with rib  66  engaging a front portion of seat  63 . 
   In the closed operating position shown in  FIGS. 6 and 8 , box  31  is positioned with the rear end of bottom wall  41  contacting end plate  14  of frame  12 ; with the input end of groove  48  adjacent to input  10  to allow the filter portions  2  travelling successively in direction  6  and at speed V 1  along conduit  8  to successively engage groove  48  and be engaged by rollers  50 ; with intermediate partition  38  coplanar with front wall  16  of frame  12 ; and with conveying device  45  directly over rollers  25  of conveyor  28 . 
   On receiving a filter portion  2 , rollers  50  feed it, still in direction  6  and at speed V 1 , between rollers  53  which, given their faster peripheral speed V 2 , accelerate it in direction  6 , detach it from the following filter portion  2 , and feed it completely through hole  49  into seat  63  before the next filter portion  2  engages rollers  53 . 
   On entering seat  63 , each filter portion  2  is deflected transversely on contacting rib  66  of deflecting member  64 —obviously in the lowered operating position—and moves gradually in direction  7 , is pushed by rollers  59  into channel  62 , and then falls by force of gravity in direction  7 , i.e. crosswise to its own axis, onto conveyor  28 , which continues feeding it in direction  7  to hopper  3  of filter assembly machine  4 . 
   When a number of side by side modules  5  are used, as in the  FIG. 1  example, conveyors  28  of modules  5  are located adjacent to one another and operate in series to define a movable bottom wall of an input portion of a conveying channel  67 , which comes out inside hopper  3  through a hole  68  formed in a lateral wall  69  of hopper  3 , and feeds a mass of filter portions  2  into hopper  3  in direction  7 . 
   Whenever, for any reason, such as jamming, work is required on a module  5 , box  31  of deflecting device  9  of module  5  is extracted and moved into the open position shown in  FIGS. 3 to 5 . By operating a consent switch (not shown) or releasing a known fast-fit connection (not shown) interposed between frames  12  and  32 , extraction of box  31  automatically deactivates relative motors  58  and  60 , and cuts off air supply along relative conduit  8 . In this connection, it should be pointed out that, when a number of modules  5  are used, the modules  5  not involved in the above operation all continue running normally, together with conveyor  28  of the module  5  involved. 
   As shown in  FIG. 4 , the length of the rod defining slide  35  is such that, when box  31  is fully open, the rear end of box  31  is located to the front of the front side of conveyor  28 , so that, by lifting deflecting member  64 , without removing any parts, and also by virtue of guide-slide coupling  33  being offset laterally with respect to plane P, all the component parts of conveying devices  45  and  46  are accessible directly from the outside, so that, any operator intervention is relatively straightforward and fast, and, above all, does not involve a complete shutdown of unit  1  if more than one module  5  is used. 
   In the  FIGS. 13 and 14  variation of unit  1 , box  31  comprises a decoupling device  70  for separating each roller  50 ,  53  from the other roller  50 ,  53  and so simplifying maintenance when box  31  is opened. 
   For this purpose, a substantially rectangular longitudinal slot  71  is formed on bottom wall  44  of cup-shaped body  42 , on the opposite side of plane P to slide  35 , and comprises a wide front portion  72 ; and a narrow rear portion  73  which extends beneath rear wall  43  of cup-shaped body  42 , is open at the rear, and is connected to wide portion  72  by an inner shoulder  74 . A slide plate  75  is located inside slot  71 , is substantially the same length as slot  71 , and comprises a wide front portion  76 , which supports shafts  51  and  54  of rollers  50  and  53  on the opposite side of plane P to slide  35 , is connected in sliding manner to wide portion  72 , but is shorter in length than wide portion  72 , and is movable towards shoulder  74  by two springs  77 ; and a narrow portion  78  connected in sliding manner to narrow portion  73  and terminating, when springs  77  are compressed, flush with the outer rear surface of rear wall  43  of cup-shaped body  42 . 
   Similarly, plate  47  is divided longitudinally along plane P into two portions  47   a  and  47   b , of which portion  47   a  is fixed, while portion  47   b  is integral with plate  75 . 
   In actual use, when box  31  is closed, contact between the rear end of narrow portion  78  and end plate  14  of frame  12  keeps rollers  50  and  53  and plate  47  in the  FIGS. 3 and 5  configuration. Conversely, when box  31  is open, plate  75  is slid back by springs  77  against shoulder  74  to offset the rollers in each pair of rollers  50  and  53 , so that any filter portions  2  can be extracted easily, and belt  57  is loosened for easy replacement. 
   In the  FIG. 15  variation of unit  1 , modules  5 , hereinafter indicated  5   a , are superimposed and turned 90° with respect to modules  5  in  FIG. 1 , and are connected individually to hopper  3  by respective output conduits  79  which come out inside hopper  3  through respective holes  68  formed in lateral wall  69  of hopper  3 . 
   The only difference between module  5  in  FIG. 1  and module  5   a  in  FIG. 15  substantially lies in the output conduit  79  of module  5   a  being a horizontal conduit, the input portion of which is connected directly to the output of channel  62  defined by the two rollers  59 , an output portion of which is connected to relative hole  68 , and an intermediate portion of which is defined by the two rollers  25 , which are substantially identical with rollers  59 , are driven by motor  29  to rotate in opposite directions, are located on opposite sides of output conduit  79 , and their axes  26  lie in a vertical plane parallel to the vertical plane defined by axes  61  of rollers  59 .