Abstract:
A transport unit is provided for cylindrical cargo items supported on a support surface and arranged in parallel in at least two layers. The center axes of cargo items are arranged on top of one another and extend essentially in the same vertical plane. At least one tension device extends between two layers. The tension device extends from an outside edge of a cargo item to an outside edge of an opposing cargo item in the layer. At least two stop elements are positioned on respective ends of the tension device. The stop elements are formed for engaging the cargo items and at least one of the stop elements being adjustably positionable on one end of the tension device. The stop elements being connectable by the tension device in a force transferring manner relative to the cargo items.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a transport unit including:
         cylindrical cargo items placed on a support surface, which are arranged parallel to one another and in at least two layers, wherein the horizontally extending center axes respectively have a distance from one another and wherein enveloping surfaces of adjacent cargo items are in a line contact with one another; and   cargo securing devices configured as tension devices, through which the cargo items are secured on the support surface against sliding or rolling in a direction perpendicular to their center axes.       

     The invention furthermore relates to a set for securing cylindrical cargo items. 
     Support surfaces in the sense of the present invention are all surfaces on which cargo items can be supported. These are also simple ground surfaces of a storage facility. Preferably, the cargo items are stored on pallets of any type, since they can be moved in a simple manner by a forklift also when they are already provided with the cargo items. 
     Cylindrical cargo items in the sense of the present invention are items where at least a contact surface is configured cylindrical, thus also bottle-shaped objects or e.g. gas containers. However, the term cylindrical cargo items includes in particular also coils of web shaped material, e.g. foil or paper, wherein the coils can preferably include sleeve-shaped winding cores. 
     BACKGROUND OF THE INVENTION 
     It is known in the art to transport cylindrical cargo items with a significantly smaller diameter than length that are unsuitable for a “standing” transport, lying horizontally and typically in plural layers stacked on top of one another, wherein the number of the cargo items disposed in one layer adjacent to one another decreases from the lowest layer to the top layer. The reason is that the cylindrical cargo objects of an upper layer are disposed in the free spaces of a layer disposed there under, so that they are respectively supported on two cargo items of the layer disposed there under. 
     The unfavorable ratio of transport volume required to actual transport volume provided. Thus, the ratio gross/net, which becomes even more unfavorable as more layers are stacked on top of one another, is a disadvantage of the known transport units identified above. Namely in the known type of stacking certain free spaces are left unused at the edges of the layers other than the lowest layer. 
     From DE 20 2009 000 365 U1 a transport unit of this type is known, in which the layers arranged on top of one another include the same number of cargo items, wherein the cargo items of the upper layer are still positioned in the free spaces of a layer respectively positioned there under. Therefore, the particular layers are always laterally offset relative to the adjacent layers. This is achieved in that the cargo items of a respective layer are respectively connected with tension devices at their faces, so that they are connected to form a disc. Though cargo items can be transported in this manner with significantly better gross/net ratio, however the width of the transport unit thus obtained is larger due to the second and possibly also fourth layer laterally protruding beyond the lowest layer, so that the transport unit is not suitable for transport devices with a limited width. 
     In order to be able to transport cargo items arranged adjacent to one another in plural layers arranged precisely on top of one another, pallets with rounded cut-outs or concave indentations are known in the art, wherein the rounded cut-outs or concave indentations are arranged below the first layer and also between two layers of cargo items. However, since differently configured pallets are required for different roll diameters a plurality of different pallets has to be stored, which causes large storage space requirements. Furthermore, this type of arranging cargo items is detrimental, since the diameters typically do not fit exactly into the concave indentations of the pallets, so that the cargo items have certain clearance in the indentations and can rock slightly. Consequently, a transport unit thus configured is not as stable as a unit configured as a block. Eventually, it is also detrimental for the pallets recited supra that the positioning is time-consuming and they cannot be sufficiently cleaned from dust and contamination, which is in particular detrimental when transporting sensitive materials. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of the present invention to improve a transport unit of the known type, so that it is suitable for transporting layers essentially arranged precisely on top of one another and including identical numbers of cargo items, and so that a fixation of the cargo items is provided in a simple manner. Thus furthermore, a respective set shall be provided for securing the cargo items. 
     The object is achieved according to the invention in that the center axes of the cargo items arranged on top of one another extend essentially in the same vertical plane and at least one tension device extends between two layers and approximately perpendicular to the center axes of the cargo items, wherein at least one tension device extends from an outside of a cargo item arranged at an edge of a layer to an outside of a cargo item arranged at an opposite edge. 
     An enveloping surface of a cargo item, wherein the enveloping surface comes closest to an outer portion of the transport unit is interpreted as an outside of a cargo item that is arranged at an edge of a layer. 
     The fact that the center axes of cargo items arranged on top of one another substantially extend in the same vertical plane means in the instant application a maximum deviation between the center axis of a cargo item and a vertical plane through another cargo item of +/−10% of the diameter of the cargo items. 
     The geometry of the tension device is independent from the different diameter of the cargo items, so that differently from the pallets recited supra with rounded cutouts or concave indentations, no different tension devices have to be stored. 
     It is also advantageous, that the height of the tension device, thus the dimension in vertical direction can be selected small, so that the height of the transport unit only slightly deviates from the sum of the cargo items arranged on top of one another, which provides a compact transport unit. 
     According to a particularly preferred embodiment of the invention it is provided that a respective stop element is arranged at both ends of the at least one tension device, wherein the stop element is respectively arranged in a respective free space between two cargo items arranged on top of one another, and the stop element is respectively supported at the enveloping surfaces of the two cargo items, so that the stop elements are configured to react to a horizontally oriented force that is introduced by the cargo items. Consequently, the tension device is connected with the stop elements in a force-transferring manner. 
     The stop elements imparting pressure on the cargo items, wherein the stop elements are retained in position by tension devices that are under tension, compress the cargo items of a layer and prevent the layer from rolling apart. When the stop elements have a large width and support the cargo items over a large length, only a tension device can be provided between the layers, wherein the tension device is centrally arranged in longitudinal direction of the cargo items, since the cargo items are sufficiently supported by the stop elements that are configured accordingly wide. 
     Accordingly, it is provided according to the invention to fixate a layer that is arranged over another layer with only three elements, namely the tension device and two stop elements, wherein the elements can be used independently from the diameter of the cargo items and thus no different elements have to be stored for fixation. 
     When the stop elements are configured with a small width, at least two tension devices with two respective stop elements shall to be provided, wherein the stop elements viewed in longitudinal direction of the cargo items are arranged in the portion of the ends of the cargo items. 
     The fixation of the cargo items of one layer according to the invention provides an extremely simple, flexible and quick option to assemble a transport unit. 
     According to the invention the cargo items are stored above the at least one tension device on the tension device and are supported on the tension device so that a gap remains between cargo items that are arranged on top of one another, wherein the gap approximately corresponds to a height of the tension device. 
     It is advantageous when the stop elements are configured wedge-shaped and have contact surfaces which enclose an angle of at least 45°, preferably at least 50° with one another. Thus, the stop surfaces can be configured as straight surfaces or they also can be configured from slightly cambered surfaces. 
     In order to obtain a compact transport unit it is provided that the stop elements do not protrude beyond a vertical plane that is tangential to the edge side cargo items and oriented towards an outer portion of the transport unit. Accordingly, the width of a transport unit is only defined by the width of a layer of cargo items which is advantageous with respect to space requirements of the transport unit. Due to the position of the stop elements within the free spaces the transport unit does not have interfering edges and protrusions which could lead to injuries of the personnel handling the transport unit. 
     In order to implement a particularly simple and quick attachment of the stop elements at the tension device it is provided according to a preferred embodiment of the invention that the stop elements are respectively provided with a support channel for the tension device, wherein the tension device is connectable with the stop element through inserting the tension device into the support channel. The tension device can slide through a stop element completely, the stop element either has to include a dead-end channel or the tension device includes a stop at one end. 
     According to the invention the tension devices can be ropes, wires, bands, bars or rods which can be configured flexible or rigid. 
     In particular it is advantageous when the tension device is provided on at least one side at least in portions with a teething which is configured to be brought into form-locking engagement with a wall section of the support channel of the stop element which is configured as a locking catch configured as a spring loaded tongue. The respective orientation of the teething is thus provided so that moving the tension device in the stop element is possible in one direction, but not in an opposite direction. 
     The tension device advantageously includes respective grooves on the longitudinal sides oriented towards the cargo items; this means the tension device includes an H-shaped cross-section. Thus, it is furthermore advantageous when cushions are arranged within the grooves, wherein the cushions are respectively oriented towards the enveloping surfaces of the cargo items. This way it is mostly avoided that impressions are formed in the cargo items in the portion of the tension devices due to the relatively high punctiform load. The cushion can be made e.g. from rubber or other suitable materials, wherein furthermore a positive effect is achieved for a rubber cushion in that a friction between the cargo items and the tension devices is prevented and thus a sliding of the cargo items is prevented. 
     As an alternative to the configuration of the tension device with an H-profile, air cushions with rectangular cross-sections can be placed adjacent to a tension device in order to prevent impressions. 
     When a tension device is configured with H-shaped cross section, a respective teething should be provided on both longitudinal sides which do not include a groove. 
     It is advantageous when the tension device and the stop elements are configured as plastic injection molded components. 
     With respect to a set for securing cylindrical cargo items the object recited supra is achieved in that the set includes a tension device, wherein two wedge shaped stop elements are connectable in a force transferring manner with both ends of the tension device. 
     The advantages recited for the transport unit are obtained analogously for the set when the tension device at least on one side includes a teething at least in sections, wherein the teething is configured to be brought in form-locking engagement with a respective wall section of a support channel of a stop element which is configured as a locking catch shaped as a spring loaded tongue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described subsequently in more detail with reference to a transport unit according to the invention with reference to drawing figures, wherein: 
         FIG. 1  illustrates a three dimensional view of a transport unit according to the invention; 
         FIG. 2  illustrates a three dimensional view of the tension device with stop elements according to  FIG. 1 ; 
         FIG. 3  illustrates a three dimensional view of the tension device according to  FIG. 2 ; 
         FIG. 4  illustrates a lateral view of the tension device with stop elements according to  FIG. 2 ; 
         FIG. 5  illustrates a lateral view of a stop element of  FIG. 2 ; 
         FIG. 6  illustrates a three dimensional view of a stop element of  FIG. 1 ; 
         FIGS. 7-10  illustrate other views and sectional views of the tension device with stop elements of  FIG. 2 ; 
         FIG. 11  illustrates a three dimensional view of an alternative transport unit; and, 
         FIG. 12  illustrates an enlarged view of the stop elements of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a transport unit  1  according to the invention in a three dimensional view including a plate shaped transport base  2  configured as a wooden pallet which is used as support surface  3  for three layers  4 - 1 ,  4 - 2 ,  4 - 3  of three respective cargo items  5  arranged parallel to one another with horizontally extending center axes  6 . In order to secure the lowest layer  4 . 1  on the pallet the two outer cargo items  5  are respectively secured with an elongated wedge  7  which has approximately the same length as the cargo items  5 . The two wedges  7  are made from cardboard and are provided on their top sides with bulges that correspond to the cargo items  5 . 
     These cargo items  5  are coils  8  of a web-shaped foil, wherein the coils are wound onto a sleeve-shaped winding core  9  made from cardboard material. The diameter of the coil  8  is typically between 30 cm and 60 cm, and the length is approximately 4.00 m. 
     Cargo items  5  of a layer  4 - 1 ,  4 - 2 ,  4 - 3 , which are arranged adjacent to one another, are in a linear contact with one another at their enveloping surfaces. 
     Between the lowest layer  4 - 1  and the center layer  4 - 2  and between the center  4 - 2  layer and the top layer  4 - 3 , three respective tension devices  10  are arranged which extend perpendicular to the center axes  6  of the cargo items  5  and which are longer than of the sum of three diameters of a cargo item  5 . One respective tension device  10  is approximately centrally arranged in longitudinal direction of the cargo items  5 , whereas the two other tension devices are positioned in the portion of the ends of the cargo items  5 . 
     The cargo items  5  of the center and upper layer  4 - 2 ,  4 - 3 , have punctiform contact with the horizontally extending tension devices  10 , so that a respective gap that corresponds to the height of the tension devices  10  remains between cargo items  5  arranged on top of one another. 
     The tension devices  10  are respectively provided with a stop element  11  at both their ends, wherein the stop element is configured wedge-shaped and is configured like an equal-side triangle in a lateral view (see  FIG. 4 ). The stop elements  11  are respectively arranged in free spaces between two cargo items arranged on top of one another, so they are supported at the envelopment surfaces of the cargo items  5 . Thus, the stop elements  11  are connected with the associated tension devices  10  in a force transferring manner, so that the cargo items  5  of a layer  4 - 1 ,  4 - 2 ,  4 - 3  are pressed against one another, and so that they cannot roll apart. 
     The stop elements  11  are sized so that they do not protrude beyond the outer edges of the cargo items  5 , so that the width of the transport unit  1  according to the invention corresponds to approximately three times the diameter of a cargo items  5 , wherein ideally the center axes  6  of cargo items  5  respectively arranged on top of one another, are arranged in the same vertical plane. 
     In case the stop elements are configured significantly wider than in  FIG. 1 , it is also possible to arrange only one tension device between the layers with stop elements engaging at ends of the tension device. 
       FIG. 2  illustrates a three dimensional view of a tension device  10  with stop elements  11  arranged at both ends of the tension device. It is evident that the tension device  10  is configured conical at its first end  12 , so that it can be easily inserted into support channel  13  in the stop element  11 . The tension device  10  respectively includes a teething  14  on its two short longitudinal sides, wherein the teething can be brought into form locking engaging with a wall section  15  of the support channel  13  of the stop element  11 , wherein the wall section  15  is configured as spring-elastic tongue  16  which is also provided with a teething  17  ( FIG. 6 ). 
     This means that inserting the tension device  10  in a direction illustrated by an arrow  18  is possible, but an opposite movement is not possible. Closures of this type are known e.g. from so-called cable-ties. 
     The opposite end  19  of the tension device  10  includes a stop  20  (see  FIG. 3 ), which is formed by a cross-sectional step of the tension device  10 . The stop  20  provides that the tension device  10  does not completely slide through the support channels  13  of the stop elements  11 , and thus would ineffective. 
     The precise configuration of the tension device  10 , which is rectangular in cross-section, can be derived from  FIG. 3 . The tension device  10  configured as a rigid rod  21  includes a rectangular cross section with two short sides and two long sides, wherein the long sides respectively approximately correspond to a width B of the support channel  13  of the stop element  11 , or slightly undercut the width, and the short sides respectively approximately correspond to a height H of the support channel  13  (see  FIG. 6 ) or slightly undercut the height H. 
     The rod  21  is provided with the teething  14  recited supra on a major portion of its short longitudinal sides. 
     Furthermore, the fork-shaped end  19  of the tension device  10 , which forms the stop  20 , is well visible in  FIG. 3 . The actual stop  20  is formed by a cross-section step which, however, only relates to the broadsides of the cross-section of the rod  21 . Below the stop  20 , the rod  21  is made from two parallel legs  22  which extend parallel to the center axis of the rod  21  and which are separated from one another through an incision  23 . This conveys the impression of a two pronged fork. 
     The configuration of the end  19  of the tension device  10  with the incision  23  facilitates to manually compress the end  19  of the tension device  10 , so that the broadened cross-section used as a stop  20  is reduced so that the tension device  10  can be pulled out of the support channels  13  of the stop elements  11 . This way, the connection of the tension device  10  of the stop elements  11  is disengageable in a simple manner. 
     The long side surfaces of the tension device  10  respectively include a groove  24  extending in longitudinal direction of tension device  10 , so that the rod  19  has an H-shaped cross section. Within the groove  24  a cushion made from cellular rubber or similar can be inserted in order to prevent a formation of impressions in the cargo items  5  on the one-hand side, and on the other hand side to counteract a sliding of the cargo items  5  on the tension devices  10 . 
       FIG. 4  illustrates a lateral view of the tension device  10  with the two stop elements  11  of  FIG. 2 , wherein a short lateral surface with the teething  14  is illustrated. Thus, the stop elements  11  include an approximately triangular configuration in the view of  FIG. 4  with two arms  25  of equal length which enclose an angle α of 60° with one another. However, the stop elements  11  differently from a triangle have a cutoff tip  26 , wherein the height of the cutoff tip  26  is slightly bigger than the width of the short side surface of the tension device  10 . 
       FIG. 5  illustrates a view according to the sectional view V-V in  FIG. 4  onto the stop element  11  with the tension device  10  run through the stop element. It is evident that the tension device  10  configured as a rod  21  has an H-shaped cross-section. Furthermore, the engaging teethings  14 ,  17  of tension device  11  and the spring loaded tongues  16  are visible. 
     A respective cushion  27  configured as a cellular rubber bar is configured in both grooves  24  of the tension device  10 . 
       FIG. 6  illustrates a three dimensional view of the stop element  11  in which the support element  13  and one of the two teethings  17  of the spring elastic tongues  16  are clearly visible. The two side surfaces  29  of the stop element  11  which have equal length respectively form a contact surface  29  of the stop element  11  with the enveloping surfaces of two cargo items  5  arranged on top of one another. 
       FIGS. 7-10  illustrate additional views or sectional views of the tension device  10  with the stop elements  11  of  FIG. 2 . Thus, the teethings  14  of the tension device  10  are illustrated in  FIGS. 8 and 9  and the two cushions  27  are illustrated in  FIG. 10 . 
       FIG. 11  illustrated an alternative transport unit  1 ′ which differs from the transport unit  1  illustrated in  FIG. 11  in that it includes additional tension devices  30  besides the recited tension devices  10 , wherein the tension devices  30  respectively engage the faces  31  of the cargo items  5  in analogy to DE 20 2009 000 365 U1 and connect the cargo items  5  of one respective layer  4 - 1 ,  4 - 2 ,  4 - 3 . 
     An enlarged illustration of the stop elements  11  in  FIG. 11  contacting the enveloping surfaces of two cargo items  5  arranged on top of one another can be derived from  FIG. 12 . It is particularly evident from  FIG. 12  that a gap corresponding to the height of tension devices  10  remains between the cargo items  5  arranged on top of one another. It also becomes apparent that the stop elements  11  contact the enveloping surfaces of the associated cargo items  5  with their stop surfaces  29 . 
     REFERENCE NUMERALS AND DESIGNATIONS 
     
         
         
           
               1  Transport Unit 
               2  Plate shaped Transport Base 
               3  Support Surface 
               4 - 1 ,  4 - 2 ,  4 - 3  Layer 
               5  Cargo item 
               6  Center Axis 
               7  Wedge 
               8  Coil 
               9  Winding Core 
               10  Tension Device 
               11  Stop Element 
               12  First End 
               13  Support Channel 
               14  Teething (a tension device) 
               15  Wall Section 
               16  Spring-Loaded Tongue 
               17  Teething (in support channel) 
               18  Arrow 
               19  Second end 
               20  Stop 
               21  Rod 
               22  Leg 
               23  Incision 
               24  Groove 
               25  Arms 
               26  Tip 
               27  Cushion 
               28  Side Surface 
               29  Contact Surface 
               30  Tension Device 
               31  Face 
             B Width 
             H Height 
             α Angle