Patent Publication Number: US-6655113-B2

Title: Method and unit for wrapping sweets

Description:
The present invention relates to a method of wrapping sweets and similar. 
     More specifically, the present invention relates to a method of wrapping sweets, the method being of the type comprising the steps of loading the sweets in bulk onto a distribution plate having a number of first peripheral seats, each for receiving a respective sweet; rotating said distribution plate about a first axis to feed said sweets into the relative said first seats, and to feed the sweets successively through an extracting station; successively extracting said sweets from the relative said first seats at said extracting station and in an extraction direction substantially parallel to said first axis; and successively feeding said sweets through a feed line, for supplying respective sheets of wrapping material, and into respective second seats on a wrapping wheel rotating about a second axis perpendicular to said first axis. 
     BACKGROUND OF THE INVENTION 
     In sweet wrapping units implementing the above method, the wrapping wheel is normally mounted over the distribution plate, and each sweet extracted from the relative first seat in said extraction direction—normally a vertical direction—continues in the same direction through the wrapping material sheet feed line—normally a horizontal feed line—and is inserted into the relative second seat on the wrapping wheel, together with the relative sheet of wrapping material, which, during insertion, is gradually folded into a U. 
     The above method normally has various functional and structural drawbacks. Firstly, transferring each sweet from the relative first seat to the relative second seat, normally by means of a pusher, the operating time of the pusher is such as to prevent the distribution plate from being operated continuously. Secondly, feeding the sheets of wrapping material along a horizontal feed line normally calls for using relatively complicated, high-cost supporting and feed devices. And finally, location of the wrapping wheel over the distribution plate impedes both access to the distribution plate itself, and any maintenance of the wrapping unit as a whole. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a method of wrapping sweets, designed to eliminate the aforementioned drawbacks. 
     According to the present invention, there is provided a method of wrapping sweets, the method comprising the steps of loading sweets in bulk onto a distribution plate having a number of first peripheral seats, each for receiving a respective sweet; rotating said distribution plate about a first axis to feed said sweets into the relative said first seats, and to feed the sweets successively through an extracting station; successively extracting said sweets from the relative said first seats at said extracting station and in an extraction direction substantially parallel to said first axis; and successively feeding said sweets through a feed line, for supplying respective sheets of wrapping material, and into respective second seats on a wrapping wheel rotating about a second axis crosswise to said first axis; and being characterized in that said sweets are fed through said feed line and into the relative said second seats in a feed direction substantially perpendicular to said extraction direction and preferably substantially radial with respect to said first and said second axis. 
     In other words, in the above method, each sweet is fed from the relative first seat on the distribution plate into the relative second seat on the wrapping wheel along a path which, as opposed to being straight, is defined by two portions: a first extending in an axial direction with respect to the distribution plate, and a second extending in a substantially crosswise direction through the wrapping material sheet feed line. This has the threefold advantage of minimizing the length of the first portion, and therefore the operating time of a pusher, if any, so that the distribution plate can be operated substantially continuously; locating the wrapping material sheet feed line parallel to the axis of the distribution plate, thus affording considerable mechanical and cost advantages; and locating the wrapping wheel alongside, as opposed to over, the distribution plate. 
     The present invention also relates to a unit for wrapping sweets. 
     According to the present invention, there is provided a unit for wrapping sweets, the unit comprising a distribution plate mounted to rotate about a first axis, the distribution plate receiving sweets in bulk and having a number of first peripheral seats, each for receiving a respective sweet and for feeding the sweet through an extracting station; a wrapping wheel rotating about a second axis crosswise to said first axis, and having a number of second seats for receiving respective said sweets; a feed line for supplying sheets of wrapping material in which to wrap said sweets, said feed line being interposed between said distribution plate and said wrapping wheel; and extracting means located at said extracting station and movable with respect to said distribution plate to extract said sweets successively from the relative said first seats in an extraction direction substantially parallel to said first axis; the unit being characterized by also comprising feed means for receiving said sweets successively from said extracting means, and for feeding the sweets successively through said feed line and into respective said second seats in a feed direction substantially perpendicular to said extraction direction and preferably substantially radial with respect to said first and said second axis. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which: 
     FIG. 1 shows a view in perspective, with parts in section and parts removed for clarity, of a preferred embodiment of the wrapping unit according to the present invention; 
     FIGS. 2 to  5  show schematic sections of the FIG. 1 unit in four different operating positions. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Number  1  in FIG. 1 indicates as a whole a wrapping unit for wrapping sweets  2  and comprising a distribution plate  3 , in turn comprising a disk  4 , which is fitted to a powered shaft  5  to rotate, anticlockwise in FIG. 1, about a vertical axis  6 , and supports a coaxial truncated-cone-shaped plate  7  positioned with its concavity facing downwards, and having, on its outer periphery, a succession of substantially circular through seats  8 . Each seat  8  is designed to receive a respective sweet  2 , which is retained inside seat  8  by disk  4 , which, at seats  8 , has a circular opening  9  coaxial with axis  6  and smaller in width than the diameter of seats  8 . 
     As it rotates about axis  6 , each seat  8  is fed by distribution plate  3  through an extracting station  10 , where each sweet  2  is engaged by a pusher  11  of an extracting assembly  12  and extracted from relative seat  8  upwards in an extraction direction  13  substantially parallel to axis  6 . 
     Extracting assembly  12  comprises two actuators  14  and  15 , which are fitted to a fixed plate located beneath disk  4  and alongside extracting station  10 , and comprise respective top output rods  16  and  17  parallel to axis  6  and fitted on their free ends with respective parallel cross members  18  and  19  facing extracting station  10  and perpendicular to respective rods  16  and  17 . Cross member  18  is located closer to disk  4  than cross member  19 , and is fitted, close to its free end facing extracting station  10 , with a pin  20 , the axis  21  of which extends in a substantially radial direction with respect to axis  6 . Pin  20  is fitted idly with a rectangular parallelepiped-shaped head  22 , the longitudinal axis of which is substantially coincident with axis  21 , and a lateral surface of which is connected to the bottom end of pusher  11 , which extends upwards from head  22  in a radial direction with respect to axis  21 . An appendix  23  projects laterally from head  22  towards cross member  19 , is perpendicular to axis  21  and to pusher  11 , and is connected to the free end of cross member  19  by a connecting rod  24  hinged to appendix  23  and to cross member  19  to rotate, with respect to appendix  23  and cross member  19 , about respective axes parallel to axis  21 . 
     Pusher  11  is aligned with the portion of opening  9  located at each instant at extracting station  10 , and faces a counter-pusher  25  forming part of extracting assembly  12 , and which is located over truncated-cone-shaped plate  7  at extracting station  10 , and moves back and forth in extraction direction  13 . Counter-pusher  25  cooperates with pusher  11  to extract a sweet  2  from a relative seat  8  at extracting station  10 , and move sweet  2  upwards in extraction direction  13  into a pickup position  26  shown in FIGS. 1,  3  and  4 . 
     In addition to distribution plate  3  and extracting assembly  12 , wrapping unit  1  also comprises a wrapping wheel  27  located alongside distribution plate  3  and mounted to rotate in steps about an axis  28  crosswise to axis  6  and extending outside the outer periphery of distribution plate  3 , just below the plane of disk  4 . Wrapping wheel  27  comprises a number of peripheral grippers  29 , which move with wrapping wheel  27  in a plane P substantially radial with respect to distribution plate  3  and through extracting station  10  and pickup position  26 , and each of which comprises a fixed jaw  30 , and a movable jaw  31  located upstream from relative fixed jaw  30  in the rotation direction (clockwise in FIG. 1) of wrapping wheel  27  about axis  28 . Each movable jaw  31  is fitted to wrapping wheel  27  to rotate towards the relative fixed jaw  30  about a relative axis parallel to axis  28  and by means of a known cam control device (not shown), so as to define, with relative fixed jaw  30 , a relative conveying seat  32  for a relative sweet  2  when relative gripper  29  is moved by wrapping wheel  27  into a loading position  33  lying in plane P and facing extracting station  10 . 
     Wrapping unit  1  also comprises, between distribution plate  3  and wrapping wheel  27 , a feed line  34  for supplying a succession of sheets  35  of wrapping material in which to wrap sweets  2 ; and a transfer assembly  36  for transferring sweets  2  successively—in a feed direction  37  parallel to plane P, substantially radial with respect to axes  6  and  28 , and substantially perpendicular to extraction direction  13 —from pickup position  26  to a respective conveying seat  32  in loading position  33 . 
     Feed line  34  extends downwards, adjacent to pickup position  26 , and through extracting station  10  in a feed direction  34   a  parallel to axis  6 , so as to feed a sheet  35  of wrapping material into an end position, in which sheet  35  of wrapping material is positioned between counter-pusher  25  and transfer assembly  36 , and with an intermediate portion at pickup position  26 . 
     Transfer assembly  36  comprises a shaft  38  powered by a known cam device (not shown) to oscillate about an axis  39  extending parallel to axis  28 , beneath disk  4 , and between wrapping wheel  27  and actuators  14  and  15 ; and two tubular shafts  40  coaxial with each other and with shaft  38 , and powered by a known cam device (not shown) to oscillate about axis  39  independently of shaft  38 , and to slide axially along shaft  38  between a parted rest position and a mating work position for the reasons and as explained in detail later on. 
     Shaft  38  is fitted with a ring  41 , from which extends outwards the arm  42  of a pressure member  43 , an end head  44  of which is movable with ring  41  between pickup position  26  and loading position  33 . Each of the two tubular shafts  40  is fitted with a ring  45 , from which extends outwards an arm  46  fitted on its free end with a block  47  perpendicular to plane P and coaxial with the other block  47 . The two blocks  47  are located on opposite sides of plane P, and, together with relative arms  46 , define respective jaws of a gripping device  48 . At their respective free ends, the two blocks  47  have respective cavities facing wrapping wheel  27  and defining, when tubular shafts  40  are in the mating position, a movable seat  49  open towards wrapping wheel  27  and for receiving a sweet  2  from a corresponding seat  8  at extracting station  10 , and for transferring the sweet  2  into loading position  33 . 
     When tubular shafts  40  are in the mating position, the free ends of the two blocks  47  are separated by a distance (FIG. 1) sufficient to define, between blocks  47 , a passage  50  for an arm  51 , which extends in plane P and radially with respect to axis  6 , is moved back and forth in plane P and parallel to extraction direction  13  by an actuating member  52 , and supports counter-pusher  25 . Conversely, when tubular shafts  40  are in the parted position (not shown), the free ends of blocks  47  are separated by a distance greater than the width of a sheet  35  of wrapping material. 
     Operation of wrapping unit  1  will now be described, relative to one sweet  2  and with reference to FIGS. 2 to  5 , as of the instant (FIG. 2) in which a sweet  2 , fed in bulk onto truncated-cone-shaped plate  7  together with the other sweets  2  not shown, is fed, by distribution plate  3  rotating continuously about axis  6 , into a relative seat  8  and then by relative seat  8  to extracting station  10 . 
     In extracting assembly  12 , equal axial displacement in the same direction of rods  16  and  17  of actuators  14  and  15  corresponds to upward or downward axial displacement of pusher  11 ; while unequal displacements of rods  16  and  17  correspond to displacement of pusher  11  in the displacement direction of rod  16 , and rotation of pusher  11  clockwise or anticlockwise in FIG. 1 about axis  21 , depending on whether displacement of rod  17  is greater or less than that of rod  16 . 
     As the full seat  8  in question nears extracting station  10 , pusher  11  is raised from the lowered position and, at the same time, rotated anticlockwise to engage opening  9  in disk  4  and contact sweet  2  (FIG.  2 ), which is also contacted by counter-pusher  25  moving down. Pusher  11  is then raised further, together with counter-pusher  25 , to engage seat  8  and feed sweet  2  in extracting direction  13  to pickup position  26  and into movable seat  49  (FIG. 3) defined by gripping device  48  already moved into extracting station  10 . As it is raised further as described above, pusher  11  is rotated clockwise (in FIG. 1) about axis  21  to accompany the displacement of seat  8  caused by distribution plate  3  rotating continuously about axis  6 . 
     At the same time, a sheet  35  of wrapping material is fed to extracting station  10  into a position facing movable seat  49 , and pressure member  43  is moved to pickup position  26  (FIGS.  3  and  4 ), on the opposite side of sheet  35  of wrapping material with respect to movable seat  49 , so that head  44  presses an intermediate portion of sheet  35  of wrapping material onto sweet  2  at pickup position  26 , and presses sweet  2  inside movable seat  49 . At this point, counter-pusher  25  is raised (FIG.  5 ), and pusher  11  is lowered and simultaneously rotated (clockwise in FIG. 1) further about axis  21  to release seat  8  while at the same time accompanying it as it rotates continuously about axis  6 . At the same time, gripping device  48  and pressure member  43  are rotated in unison (FIG. 5) clockwise about axis  39  to feed sweet  2  and relative sheet  35  of wrapping material in feed direction  37  from pickup position  26  to loading position  33  and into the conveying seat  32  defined by a gripper  29  arrested in the open position at loading position  33  to receive sweet  2  and simultaneously fold relative sheet  35  of wrapping material into a U about sweet  2 . Gripper  29  is then closed about sweet  2  and relative sheet  35  of wrapping material, so that gripping device  48  is free to return to extracting station  10  (FIG.  2 ), whereas pressure member  43 , before it can return to pickup position  26 , must wait for wrapping wheel  27  to move forward one step (FIG.  3 ). 
     As gripping device  48  moves to pickup position  26 , the two blocks  47  are parted to avoid interfering with the next sheet  35  of wrapping material fed to extracting station  10  along feed line  34 .