Abstract:
In a device for relocating a product, in particular a blister, in a packaging machine and with an associated method, the product is received at a supply location and deposited at a deposition location. The relocating device has a first pivotable relocating arm and a second pivotable relocating arm which each have a holding mechanism for the product. The relocating arms can be adjusted along different trajectories between a transfer position at the common supply location and a deposition position at the common deposition location, and pass each other during their adjustment motion.

Description:
This application is the national stage of PCT/EP2005/008618 filed on Aug. 9, 2005 and also claims Paris Convention priority of DE 10 2004 043 332.1 filed Sep. 8, 2004. 
   BACKGROUND OF THE INVENTION 
   The invention concerns a relocating device for relocating a product in a packaging machine, wherein the product can be received by the relocating device at a supply location, and can be disposed at a deposition location, wherein the relocating device comprises a first pivotable relocating arm and a second pivotable relocating arm each comprising a holding means for the product. 
   The invention also concerns a method for relocating a product in a packaging machine, wherein the product is received by a relocating device at a supply location and is disposed at a deposition location, wherein the relocating device comprises a first pivotable relocating arm and a second pivotable relocating arm each having a holding means for the product. 
   The relocation of a blister in a blister packaging machine is described below by means of example. The invention is, however, not limited thereto. 
   In a blister packaging machine, a plurality of cups are formed in an endless sheet web, into each of which one or more products are disposed, which may e.g. be pharmaceuticals, in particular, tablets or capsules. A covering foil is subsequently sealed thereon which tightly encloses the products in the cups. The blister band formed in this manner is separated in a punching or cutting unit into blister strips (called blisters below). 
   In a conventional blister packaging machine (WO 00/68086), the blister is relocated using a relocating device which comprises two pivot arms which are disposed next to each other. 
   Each pivot arm may receive one blister at a supply location, wherein each pivot arm has its own supply location, and the supply locations are disposed next to each other in a punching unit. Each pivot arm disposes the received blister onto a continuous conveying belt, wherein the blisters are disposed on the conveying belts with mutual offset in the transport direction. The blisters are subsequently transferred to a common continuous conveying belt and supplied to the packaging unit. 
   In particular for packaging medication, it is often necessary or conventional to fill several blisters into a folded box or into another package. Towards this end, a stack comprising a corresponding number of blisters must be formed from the individual blisters, which is then packed into the folded box or another package. A special stacking unit is provided to form the stack, which is disposed at the end of the conveyor belt. The blisters which were recognized as being incomplete and/or improperly sealed are rejected directly upstream of the stacking unit, and the presence of the blisters is checked. This requires substantial equipment and handling expense in order to form a stack from a desired number of blisters, which can be transferred to a downstream cartoning device. Moreover, changing the blister format requires a plurality of adjustments and modifications which increases the downtime of the packaging machine. 
   DE 199 17 436 C2 also describes a device for relocating a blister onto a conveying device. The relocating device is designed as a lowering device which passes through the punching tool so that the blisters are deposited on the conveying device that extends below the punching tool. The relatively long cycle time required for relocating the blister is particularly disadvantageous, since the punching tool is blocked during downward transport of the blister onto the conveying device. 
   It is the underlying purpose of the invention to produce a relocating device and a method of the above-mentioned type for relocating the blisters in a simple and rapid fashion with a fast cycle time. 
   SUMMARY OF THE INVENTION 
   With regard to the device, the above-mentioned object is achieved with a relocating device comprising the characterizing features of the independent device claim. The first pivotable relocating arm and the second pivotable relocating arm are thereby adjustable along different trajectories between a transfer position at the common supply location and a deposition position at the common deposition location, and pass each other during their adjustment motion. 
   In accordance with the invention, each relocating arm receives the blister at its single common supply location using its holding means, which may e.g. be a suctioning means with at least one suctioning device, wherein the relocating arm is in its transfer position. The relocating arm pivots into its deposition position at one single deposition location which is common to both relocating arms, whereupon the holding means is released and the blister is freed and thereby deposited. The relocating arm subsequently pivots back along the same trajectory, i.e. each relocating arm performs a reversing, reciprocating pivoting motion between the transfer position at the supply location and the deposition position at the deposition location. Advantageously, the motions of the relocating arms are thereby mutually offset by half a work cycle, i.e. when one relocating arm is in its transfer position at the common supply location, the other relocating arm is in or close to its deposition position at the common deposition location. It is, however, also feasible that the motions of the relocating arms are mutually offset by approximately ⅓ or approximately ⅖ of a work cycle. 
   When the relocating arms are pivoted from their transfer position into their deposition position or from their deposition position back to the transfer position, they move along different trajectories, such that they evade each other and move past each other. This provides a relocating device for alternately receiving blisters from the first or second relocating arm which are deposited at the deposition location. At the deposition location which may advantageously be a cell of a continuous conveying device, either each individual blister may be transported away, or alternatively a blister stack may initially be formed and transported away. 
   The different trajectories during pivoting or adjustment of the relocating arms are obtained in an advantageous embodiment of the invention in that each relocating arm can be pivoted about a first axis and about a second axis which extends substantially perpendicularly thereto. Pivoting about the first axis bridges the separation between the supply location and the deposition location, wherein the two first axes of the two relocating arms advantageously extend parallel to each other. Pivoting about the second axis mainly serves to align and exactly position the blister. For this reason, the second axes advantageously extend in the longitudinal direction of the respective relocating arm or parallel thereto. When a blister has been received by the holding means of the relocating arm at the supply position, the relocating arm pivots about its first axis and thereby moves towards the deposition location. At the same time, the arm is pivoted about its second axis, wherein the blister and the relocating arm are turned by preferably approximately 180°, thereby changing the orientation such that it can be directly deposited at the deposition location after arrival. 
   Exact motion control of the relocating arms is preferably achieved in that each relocating arm has its own drive for pivoting about its first axis, in particular, its own servomotor. Each relocating arm may also have a further, separate drive and, in particular, also a further servomotor for pivoting about its second axis. Each relocating arm is then driven by two servomotors which can be driven independently of each other to ensure very fast and exact motion of the relocating arms. The relocating arm may alternatively be mechanically pivoted about its second axis using a control crank or cam. 
   The basic constructive design of each relocating arm comprises a pivot piece that can be pivoted about the first axis. An arm part is pivotably disposed about the second axis on the pivot piece. When the longitudinal axis of the arm part coincides with the second axis, the relocating arm moves upon adjustment substantially within one plane which is defined by the pivoting motion about the first axis. The arm part of at least one relocating arm is not directly mounted to the pivot piece but held at a separation from the second axis via a spacer. Due to this separation or offset, upon adjustment of the relocating arm, the trajectory is composed of the pivoting motion of the pivot piece about the first axis and pivoting of the arm part about the second axis, performed on a circular path at a separation, which produces a curved trajectory. A corresponding curved trajectory may also be provided for both relocating arms by holding each arm part at a separation from the second axis by one spacer each. 
   The trajectories of the two relocating arms are matched such that they do not contact each other during opposite pivoting motions between the transfer position and the deposition position, rather evade and move past each other. 
   In a preferred embodiment of the invention, one of the relocating arms is pivoted substantially in one plane about its first axis, and the other relocating arm extends on a curved path about the relocating arm that is pivoted in the plane. 
   In a further preferred embodiment of the invention, the common supply location is formed directly on the punching or cutting device which separates the blister from the endless blister band. That section of the blister band which forms the blister to be separated, is already grasped by the holding device or suctioning devices prior to activation of the punching or cutting device, and the blister is subsequently separated from the blister band, with the blister already being safely held by the holding device of the relocating arm in this phase. 
   The relocating device is preferably disposed on the side of the blister opposite to the punching or cutting device, such that the relocating process is entirely independent of the punching and/or cutting process, thereby also preventing any collision between the relocating device and the advancing blister band. 
   According to a further development of the invention, an ejector shaft may be provided into which the blister is introduced by the relocating device in order to reject incomplete and/or improperly sealed blisters. The ejector shaft preferably comprises a scraper for scraping the blister off the holding device of the respective relocating arm. The holding means or the suctioning device of the relocating arm is additionally deactivated, wherein the released blister falls into the ejector shaft and is supplied to a collecting station for blisters to be rejected. 
   The above-mentioned object is achieved with respect to a method by the characterizing features of the independent method claim. The motion sequences of the relocating arms are thereby adjusted to each other such that one of the relocating arms is in its transfer position at the common supply location, whereas the other relocating arm is in its deposition location at the common deposition location. The relocating arms are reciprocated on different trajectories between the transfer position at the supply location and the deposition position at the deposition location, wherein they move past each other during their adjustment motion. 
   Additional features of the method can also be extracted from the above-mentioned description of the device. 
   Further details and features of the invention can be extracted from the following description of an embodiment with reference to the drawing. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
       FIG. 1  shows a schematic perspective view of an inventive relocating device, wherein one of the relocating arms is in the transfer position and the other relocating arm is in the deposition position; 
       FIG. 2  shows the relocating device according to  FIG. 1  after taking over a blister and deposition of the relocated blister; 
       FIG. 3  shows the relocating device according to  FIG. 2  in a first phase of adjustment of the relocating arms; 
       FIG. 4  shows the relocating device according to  FIG. 3  in a second phase of adjustment of the relocating arms; 
       FIG. 5  shows the relocating device according to  FIG. 4  in a third phase of adjustment of the relocating arms; 
       FIG. 6  shows the relocating device according to  FIG. 5 , wherein the relocating arms have reached their transfer or deposition position; and 
       FIG. 7  shows the relocating device according to  FIG. 6  after transfer of a blister and depositing the relocated blister. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   In a blister packaging machine  10 , only sections of which are shown in the figures, an endless blister band  11  is produced in a conventional fashion that comprises a plurality of cups  18  ( FIG. 3 ) each containing at least one product. The cups  18  are conventionally sealed with a covering foil. The blister band  11  is supplied to a schematically represented cutting or punching device  12  which separates a blister strip B from the blister band  11  ( FIG. 2 ). 
   The blister packaging machine  10  moreover comprises a continuous conveying device  13  which is shown only schematically as an endless continuous conveyor belt which carries, on its outer side, a plurality of projecting fingers  14  disposed at separations from each other to define intermediate cells. One of the cells forms an individual deposition location  15  during relocation of the blisters as described below. The blisters B which are separated from the blister band  11  using the punching or cutting device  12  may be received on the punching or cutting device  12  using a relocating device  20  such that one single supply location for the blisters B is formed at that location. The blisters are received and inserted by the relocating device  20  into the first cell of the conveying device  13 , and deposited at the deposition location  15  thereby forming a stack S comprising several blisters B ( FIG. 2 ). 
   The relocating device  10  has a frame-less drive housing  17  on which a first pivotable relocating arm  21  and a second pivotable relocating arm  28  are disposed. 
   The first pivotable relocating arm  21  comprises a pivot piece  27  which is disposed on the drive housing  17  to be pivotable about a first axis H 1 . The pivot drive for the pivot motion about the first axis H 1  is a servomotor (not shown). The first relocating arm  21  moreover comprises an arm part  22  that is formed by two parallel bars  22   a ,  22   b . The two bars  22   a  and  22   b  are connected at their lower ends, located close to the pivot piece  27 , to a bearing block  25  which is disposed on the pivot piece  27  via spacer  26  to be pivotable about a second axis S 1 . The second axis S 1  substantially extends perpendicularly to the first axis H 1  and parallel to the longitudinal extension of the bar parts  22   a  and  22   b . The second axis S 1  is offset from the longitudinal extension of the arm part  22  due to the spacer  26 , such that the arm part  22  pivots on a circular arc at a clear separation from the second axis S 1 . The pivot drive for pivoting about the second axis S 1  is also effected by a further servomotor (not shown). 
   At their upper free end facing away from the bearing block  25 , the bar parts  22   a ,  22   b  each have a suctioning device  23 ,  24  or corresponding suctioning heads which can be conventionally loaded with an underpressure. Upon activation of the suctioning devices  23 ,  24 , a blister provided at the supply location may be received and held by the first relocating arm. 
   The second pivotable relocating arm  28  has a similar structure to that of the first pivotable relocating arm  21 . It also comprises a pivot piece  33  which is pivotably disposed on the drive housing  17  and can be pivoted about a first axis H 2  using a servomotor (not shown) and pivotably bears an arm part  29 . The first axis H 2  of the second relocating arm  28  extends parallel to the first axis H 1  of the first relocating arm  21 . The arm part  29  of the second relocating arm  28  also comprises second bar parts  29   a  and  29   b  whose lower ends are mounted on a bearing block  32  close to the pivot part  33 . 
   The bearing block  32  is disposed on the pivot part  33  to be pivotable about a second axis S 2 , wherein the pivot motion about the second axis S 2  of the second relocating arm  28  is also performed using a further servomotor (not shown). The second pivot axis S 2  of the second relocating arm  28  extends substantially perpendicularly to the first axis H 2  of the second relocating arm  28  and along or in the direct vicinity parallel to the longitudinal axis of the arm part  29 . Two suctioning devices  39 ,  31  are provided at the upper free end of the arm part  29 , which may hold a blister B. 
   Since the second axis S 2  of the second relocating arm  28  extends along or close to the longitudinal central axis of the arm part  29 , the arm part performs a motion substantially in one plane during pivoting about the first axis H 1 , wherein the arm part  29  rotates about itself and about the second axis S 2 . 
   As is shown in  FIG. 1 , the relocating device  20  is disposed between the supply location which is common to both relocating arms  21 ,  28  and formed between the cutting or punching device  12 , and the deposition location which is common to both relocating arms  21 ,  28  and formed on the continuous conveying device  13 , such that the blisters B must be turned by approximately 180° during the relocating motion, which is obtained through pivoting the arm parts  22  or  29  about the respective second axis S 1  or S 2 . 
   The relocation of a blister B from the supply location to the deposition location and returning the relocating arm after depositing the blister are explained in more detail below with reference to  FIGS. 1 through 7 . 
   In the position shown in  FIG. 1 , the first relocating arm  21  is in its transfer position, in which its suctioning devices  23 ,  24  are disposed at the supply location formed on the cutting or punching device  12 . The suctioning devices  23  and  24  abut the blister band  11  which they have suctioned by underpressure, wherein directly thereafter, a blister is separated from the blister band  11  using the punching or cutting device  12 . 
   At the same time, the second relocating arm  28  is in its deposition position in which the blister B held by its suctioning devices  30  and  31  is disposed at the deposition location  15  in the cell of the conveying device  13 . The blister B is released by cancelling the underpressure at the suctioning devices  30  and  31  of the second relocating arm  29 .  FIG. 1  shows a type of operation, wherein a blister stack S formed from several blisters B is formed in the cell of the conveying device  13  (see  FIGS. 2 and 7 ), however, the deposited blister may also be transported away in the conveying device as a single blister. 
   Directly after separating the blister B from the blister band  11 , the first relocating arm  21  including retained blister B is adjusted to the deposition position, while the second relocating arm  28  is simultaneously pivoted to its transfer position at the supply location after depositing the blister B on the conveying device  13 . Both relocating arms  21  and  28  perform a pivoting motion which is formed by superposition of their pivoting motion about their first axes H 1  and H 2  and their pivoting motion about their second axes S 1  and S 2 , respectively ( FIGS. 2 ,  3 , and  4 ). The second relocating arm  28  pivots substantially in one plane which is determined by pivoting of the pivot piece  33  about the first axis H 2 , wherein at the same time the arm part  29  is turned substantially about itself in order to change the orientation of the suctioning devices  39 ,  31  as desired. 
   The first relocating arm  21  follows an evasive, curved trajectory due to the spacer  26  and the accompanying substantially larger offset of the longitudinal axis of the arm part  22  relative to the second axis S 1 , such that it can laterally deflect relative to the motion of the second relocating arm  28  ( FIGS. 3 and 4 ). 
   Rotation of the relocating arms  21  and  28  about their respective second axes S 1  and S 2  is terminated in the position shown in  FIG. 5 , and the relocating arms have reached the desired orientation of their suctioning devices  23 ,  24  and  30 ,  31 , respectively. Further pivoting about the respective first axes H 1  and H 2 , moves the suctioning devices  30 ,  31  of the second relocating arm  28  into their transfer position at the supply position ( FIG. 6 ), while at the same time, the suctioning devices  23 ,  24  of the first relocating arm  21  insert their blister B into the cell of the conveying device  13  and release it after reaching the deposition position at the deposition location  15  ( FIG. 6 ). 
   Immediately afterwards, the second relocating arm  28  takes over a newly punched blister B and returns to the deposition position shown in  FIG. 1  along its trajectory which extends substantially in one plane. After depositing the blister, the first relocating arm  21  simultaneously returns to its transfer position shown in  FIG. 1  along its curved trajectory on which it circulates around the second relocating arm to prevent any collision, and the described cycle starts again.