Abstract:
An apparatus for charging containers with a flat item stack, includes a supply conveyor; intermediate containers; and a transporting device carrying the intermediate containers into first and second stations. In the first station an item stack is loaded from the supply conveyor into the intermediate container, and in the second station an item stack is loaded from the intermediate container into a packaging container supported in the second station. A device rotates each intermediate container about an axis perpendicular to the advancing direction of the items on the supply conveyor from a first angular position into a second angular position and then back into the first angular position during travel of the intermediate container from the first station into the second station and back into the first station. A removing device in the second station carries away a filled packaging container.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the priority of Swiss Application No. 2000 0608/00 filed Mar. 29, 2000, which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 4,052,838 describes an apparatus for packaging stacked, flat items (potato chips) into tubular packaging containers. In this apparatus a continuous flow of items is advanced to a downwardly inclined, pivotal trough. Item stacks are formed by means of two, alternatingly upward shifted separator lances arranged spaced from one another above the trough. The separated stacks slide into respective tubes which are arranged as wheel spokes and which are rotatable as a unit. As soon as a tube is filled, the tube assembly is incrementally rotated by one step about a horizontal axis. A tubular packaging container having a closed bottom is pulled over the filled tube in a subsequent station. As the tube assembly continues to rotate, the filled packaging container is deposited in a standing orientation on a removing conveyor belt. 
     Since the items are first deposited in a tube and then the container is inserted over the tube, the container has to have a greater diameter than necessary for receiving the items. It is a further disadvantage of such a prior art arrangement that when the item stack slides into the tube, the leading items of the stack are likely to tilt which may lead to operational disturbances because then only insufficient space is available in the tube for the entire stack. Also, for this reason, underweight packages may result which must be rejected as waste. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an improved apparatus of the above-outlined type from which the discussed disadvantages are eliminated. 
     This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the apparatus for charging containers with a flat item stack includes a supply conveyor; intermediate containers; and a transporting device carrying the intermediate containers into first and second stations. In the first station an item stack is loaded from the supply conveyor into the intermediate container, and in the second station an item stack is loaded from the intermediate container into a packaging container supported in the second station. A device rotates each intermediate container about an axis perpendicular to the advancing direction of the items on the supply conveyor from a first angular position into a second angular position and then back into the first angular position during travel of the intermediate container from the first station into the second station and back into the first station. A removing device in the second station carries away a filled packaging container. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1-8 are schematic side elevational views of the apparatus according to a preferred embodiment of the invention, illustrating consecutive operational positions. 
     FIGS. 9 and 10 are sectional elevational views of filled containers. 
     FIG. 11 is a schematic top plan view of a series of intermediate containers. 
     FIGS. 12 and 13 are schematic perspective views of an intermediate container shown in different operational phases. 
     FIG. 14 is a schematic side elevational view of a variant of a component of the apparatus according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning to FIGS. 1-8, the apparatus illustrated therein includes a supply conveyor  9 , for example, a pivotal trough, on which a string  10  of stack-like arranged flat items, particularly potato chips, are continuously advanced in a conveying direction A. At a first station  12  the items  11  are backed up so that they assume a stacked, edgewise standing orientation. The apparatus further includes an intermediate conveyor  13  constituted by a rotary disk or platform  15  rotatable about a horizontal axis  14  and carrying four circumferentially arranged rotary shafts  16  which are oriented parallel to the axis  14  and are uniformly spaced therefrom. Each shaft  16  is connected with an intermediate container  17 , and each container  17  is associated with a holding element including a rotary shaft  18  rotatably supported on the respective intermediate container  17 . Two holding fingers  19 ,  20  extend from each shaft  18 . The finger  19  is fixedly connected with the shaft  18  at the outer end of the intermediate container  17 . The finger  20  is longitudinally shiftable on the shaft  18  and may be immobilized to adapt the distance between the fingers  19 ,  20  to the length of the stack  27  to be formed. 
     As may be observed in FIGS. 12 and 13, the intermediate containers  17  are each composed of two prismatic container parts  21  whose facing sides are concave and are spaced from one another. In the rotary position of the shaft  18  illustrated in FIG. 12 the ends of the fingers  19 ,  20  are situated externally of the intermediate container  17  whereas in the rotary position of the shaft  18  shown in FIG. 13 the ends of the fingers  19 ,  20  are positioned within the inner cross section of the intermediate container  17 . 
     An inclined guide rail  24  is affixed to the machine frame in the first station  12 . On the rail  24  a pick-up floor  25  is arranged for displacement by a non-illustrated motor from a fixed extended position shown in FIG. 1 into a settable base position illustrated in FIG. 4. A separator lance  26  oriented transversely to the conveying direction A and shiftable by means of a further, non-illustrated motor is arranged above the conveyor  10  at the downstream end thereof. Every time the pick-up floor  25  has performed its stroke from its extended position into its position in FIG. 3 the separator lance  26  is lowered and thus separates a stack  27  of potato chips within the intermediate container  17 . Upon withdrawal of the pick-up floor  25  into the base position shown in FIG. 4, the respective shaft  18  is turned, so that its holding fingers  19 ,  20  arrive from their position shown in FIG. 12 into the position illustrated in FIG.  13  and thus straddle the stack  27 . Thereafter the platform  15  is turned so that the filled intermediate container  17  arrives in the second station  30 . 
     Simultaneously with the rotation of the platform  15  the filled intermediate container  17  is rotated by the shaft  16  such that when arriving in the second station  30  (carried by the platform  15 ), the non-shiftable (fixed) holding finger  19  is situated at the bottom. A guide rail  31  is fixedly attached to the machine frame in the second station  30 . An ejector pusher  32  which is shiftable by means of a non-illustrated motor from its position shown in FIGS. 1 and 6 into the position illustrated in FIG. 8 is mounted on the rail  31 . A rotary removing disk  33  is positioned in the second station  30  and carries two non-illustrated holding elements for the cylindrical container  34  to be filled. One end of the empty packaging containers  34  is closed by a sealing foil or film  35  (shown in FIG. 9) and a lid  36 . 
     The rotary disk  33  is turned in 180° increments. In the second station  30  a packaging container  34  is positioned with its open end oriented downward and ready to receive an item stack  27  from an intermediate container  17 . At the diametrically opposite side of the disk  33  a filled container  34  is exchanged for an empty container  34  by non-illustrated means, for example, a gripper. The filled container  34  is subsequently closed by a crimped-on bottom  37  (FIGS.  9  and  10 ). 
     FIGS. 1-8 schematically illustrate the sequential operation of the apparatus according to the invention. FIG. 1 shows the initial position in which the item string  10  is backed up on the extended pick-up floor  25 , and the separating lance  26  is in its raised position. One of the intermediate containers  17   a  is situated in the first station  12  in alignment with the conveyor  9 . The holding fingers  19 ,  20  of the intermediate container  17   a  are in the withdrawn position as shown in FIG.  12 . 
     FIG. 2 shows the motion of the pick-up floor  25  while the items  11  are loaded into the intermediate container  17   a . Before the pick-up floor  25  has reached its base position, the separating lance  26  is lowered and thus a stack  27  is divided from the string  10 , as shown in FIG.  3 . In the subsequent base position of the pick-up floor  25  according to FIG. 4 the stack  27  is fully inside the intermediate container  17   a . The respective shaft  18   a  is rotated so that the fingers  19   a ,  20   a  extend into the container  17   a  and straddle the separated stack  27 . 
     Thereafter the platform  15  is turned 90° clockwise and, at the same time, the respective shaft  16  is rotated counterclockwise as shown in FIG. 5, until the position of FIG. 6 is attained and the intermediate container  17   a  is oriented vertically and the axially immovable holding finger  19   a  is positioned at the bottom. The intermediate container  17   a  is in axial alignment with the container  34   a  which is to be filled and which is situated above the intermediate container  17   a.    
     As soon as the intermediate container  17   a  has reached a position above the ejector pusher  32 , the shaft  18   a  is pivoted backward so that the fingers  19   a ,  20   a  are withdrawn from the region of the inner cross section of the intermediate container  17 , and the ejector pusher  32  is raised (FIG. 7) until the entire stack  27  is pushed into the container  34   a  (FIG.  8 ). Thereafter, the disk  33  is rotated 180° and the filled container  34   a  is exchanged for an empty container at the diametrically opposite side of the disk  33 . A guide plate  38  is provided as shown in FIG. 8 to ensure that the items do not drop out of the packaging container  34   a  during turning of the disk  33 . During this phase the subsequent intermediate container  17   b  is filled in the earlier-described manner. 
     During subsequent further rotation of the platform  15 , the shaft  16   a  of the intermediate container  17   a  is rotated either in the same or in the opposite direction until the intermediate container  17   a  again assumes its position relative to the platform  15  as shown in the first station  12  (FIG.  1 ). In contrast to the illustration in FIGS. 1-8, the fingers  19  and  20  remain in the outwardly pivoted position as the intermediate container  17  moves from the second station  30  into the first station  12 . 
     As shown in FIGS. 11 and 14, several intermediate containers  17  may be positioned side-by-side on a common shaft  16 . In such a case, an equal number of supply conveyors  19  are situated side-by-side and the removal conveyor  33  has a corresponding number of parallel receivers for the containers  34 . The shafts  18  are mounted in pairs on the respective container part  21  and may be pivoted jointly, for example, by means of a toothed belt  43  and a motor  44  to move the fingers  19 ,  20  from an inward position shown at the part  21   a  in an outwardly-pivoted, withdrawn position shown at the other part  21   b.    
     FIG. 14 schematically shows a variant of the rotary platform  15  described earlier. In the structure of FIG. 14 two disks  46  are provided which are rigidly connected to the shaft  14  driven by a motor  47 . On the shaft  14 , axially externally of the disks  46 , a respective bushing  48  is supported, each carrying two annular gears  49 ,  50 . Each gear  49  meshes with a respective gear  51  continuously driven by a motor  52 . The two gears  51  rotate in opposite directions. The gears  50  mesh with four gears  53  rotatably supported on the four rotary shafts  16  (only two are visible in FIG.  14 ). The gears  53  may be coupled to the respective rotary shafts  16  by a respective, individually operable clutch-and-brake unit  54 . Such clutch-and-brake units are known and are used, for example, in manual transmissions of motor vehicles. The units  54  are switchable into three positions: in a first position the rotary shaft  16  is coupled to the disks  46 ; in a second position the shaft  16  is coupled to the gear  53  and in a third or intermediate position the shaft  16  may rotate freely. The actuation of the units  54  may be effected, for example, by limit switches  58 ,  59  mounted on the disks  46 . One limit switch  58  cooperates with a fixed cam  60  arranged immediately after the first station  12  and switches one unit  54  associated with a motor  52  into the second position and switches the second unit  54  of the same shaft  16  into the intermediate position. As soon as the shaft  16  has reached the desired angular position relative to the disks  46 , a cam  61  connected with the shaft  16  actuates the other limit switch  59  thus switching the first unit  54  in first position. The reverse rotation of the shaft  16  upon leaving the second station  30  occurs in a similar manner. 
     It is, however, also feasible to rotate the intermediate container  17  by the shaft  16  always in the same sense relative to the platform  15 . In such a variant one of the motors  52  as well as the associated parts  48 ,  53  and  54  are dispensed with and the remaining units  54  may be switched only in the first and second positions and cannot be switched into an intermediate position. Such a variant is of very simple construction. 
     The described apparatus has, in particular, the following advantages: 
     Cylindrical or saddle-shaped items such as potato chips may be in conveyed in a stable manner as an overlapping string  10  only in the position illustrated in FIGS. 1-8 in which their convex side is oriented opposite the conveying direction A. If such a string is directly filled into a packaging container  34 , the convex side of the items  11  would be oriented towards the lid  36 . Such a result would be disadvantageous for the consumer, because the items  11  could be grasped in the filled container  34  only with difficulty. By virtue of the rotary motion of the intermediate container  17  relative to the platform  15  as the container travels between the stations  12  and  30 , such a disadvantage is eliminated according to the invention. The same advantage may be achieved by filling other, flat stacked products, for example, cookies having a chocolate cover layer on only one face which should be oriented in the container  34  towards the lid  36 . It is to be understood that the same advantage could be achieved by filling the container  34  directly, but from the side of the lid  36 . In such a case, however, significant difficulties arise concerning a securely sealed attachment of the foil  35 . It would be practically unavoidable that at one part of the container  34  its upper end face becomes soiled by crumbs or grease which would make a hermetically tight sealing of the foil  35  impossible. 
     The same apparatus may also be used, without such a rotary motion, for packaging other, for example, non-curved items. In case such a possibility is to be reserved for the apparatus, the packaging container  34  which is standing by for being filled, would be arranged radially to the axis of the shaft  14 , in contrast to the illustration in FIGS. 1-8. Such a mode of operation would have the advantage that the ejector pusher  32 , dependent upon the stack height, would execute a shorter stroke and thus the cycling period would be shortened. 
     Thus, the apparatus according to the invention has a substantial versatility. It makes possible a gentle handling of the items  11 , particularly during the rotary motions. Further, a secure filling of the containers is achieved because a tilting of the products  11  at one end of the stack  27  is securely prevented. A potential contamination of the sealed region by parts of the items is avoided. By virtue of the simultaneous occurrence of the rotary motion of the intermediate container while it travels from the first station to the second station and while it travels from the second station to the first station (reverse rotation) results in a high output. 
     It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.