Abstract:
An apparatus for sorting piece goods may include a receiving surface which can rotate about a predefined rotation axis and is designed to receive the piece goods. The apparatus may include a first guide rail for guiding the piece goods, wherein this guide rail has a gap through which one region of the piece goods passes and by means of which another region of the piece goods is held. The apparatus may include a turning device which pivots the piece goods with respect to a longitudinal direction of the piece goods. The apparatus may include a separating device which separates out some of the sorted piece goods which are not guided in a predefined manner by the first guide rail or by the turning device. The turning device may be arranged upstream of the separating device in the movement direction of the piece goods.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of priority of German Patent Application No. 10 2007 049 009.9, filed Oct. 11, 2007, pursuant to 35 U.S.C. 119(a)-(d), the disclosure of which is incorporated herein by reference in its entirety as if fully set forth herein. 
       TECHNICAL FIELD 
       [0002]    The present disclosure relates to an apparatus and to a method for sorting performs. However, it is pointed out that the apparatus according to the invention and the method according to the invention are also suitable for sorting other bodies and in particular other elongate bodies with an external profile. 
       BACKGROUND 
       [0003]    The aforementioned preforms are used in the prior art in beverage production, in order subsequently to be expanded to form beverage containers. It is customary for these containers to pass initially in an unordered fashion onto a sorting device, and in this sorting device to be oriented in a predefined manner in order then to pass in a sorted fashion to a further installation, such as a blowing machine. 
         [0004]    EP 1 592 630 B1 discloses an orienting device for bottle preforms for passing through a blowing machine. In said document, a movable inclined device is provided which has a plurality of cells which are intended to hold in each case one preform in a horizontal position. The preforms thus held in the horizontal position are conveyed into a guide slot in which they are rotated due to the particular configuration of this slot and then are conveyed further in this rotated position. 
         [0005]    EP 1 690 813 A1 discloses an apparatus and a method for aligning elongate, preferably cylindrical objects having a profiled contour. In this apparatus, the preforms are placed on a rotating disc, pushed outwards by means of the centrifugal force and finally guided into a guide channel. In this apparatus, too, the preforms are rotated or tilted about their longitudinal axis. Prior to tilting, those preforms which are not arranged in a certain desired position with respect to the guide rail are separated out. In order to increase the efficiency of this apparatus, a first guide element is provided, wherein between this guide element and the rotating disc there is a gap which allows the main body of the preforms to pass, but not the respective supporting collar of these preforms. In addition, an additional element is provided which is arranged radially inside the guide element and which brings about a pre-orientation of the preforms. 
         [0006]    DE 10 2005 048 126 A1 discloses a method and an apparatus for sorting preforms. Here, the preforms are fed for sorting purposes to a rotatable rotor which positions the preforms along a stationary guide rail under the effect of the centrifugal force, wherein a separation of the preforms is carried out at the outer circumference of this rotor. 
         [0007]    It may therefore be desirable to provide an apparatus for sorting preforms which allows a higher operating speed compared to the prior art. 
       SUMMARY OF THE INVENTION 
       [0008]    An apparatus according to the invention for sorting piece goods, and in particular preforms, comprises a receiving surface which can rotate about a predefined rotation axis and is designed to receive the piece goods. Also provided is a first guide rail for guiding the piece goods, wherein the guide rail forms a gap through which one region of the piece goods passes and by means of which another region of the piece goods is held. Also provided is a turning device which pivots the piece goods with respect to a longitudinal direction of the piece goods. Finally, a separating device is provided which separates out some of the sorted piece goods. According to the invention, the turning device is arranged upstream of the separating device in the movement direction of the piece goods. According to various aspects, the first guide rail forms the gap with the upper face of the receiving surface. 
         [0009]    The receiving surface thus serves on the one hand for (pre-)sorting the preforms, but on the other hand also—for example, by means of its outer circumference—for retaining the latter. According to various aspects, the preforms are loosely retained. According to some aspects, the receiving surface is arranged horizontally, but may also be arranged at an angle other than 0° with respect to the horizontal, with an inclination of between about 5° and about 30° then being exemplary. 
         [0010]    A guide rail is understood to mean a rail delimited on both sides by a wall, wherein the preform can be guided between these two walls. The main body of this preform, which usually has a smaller cross section than its mouth collar for example, can pass through this gap and the collar is held at the gap. In this way, the preform is usually also brought into a predefined position, since the centre of gravity of the preform is located below the aforementioned circumferential collar. In particular, that portion of the piece goods which are not correctly guided by the guide rails or the turning device are separated out. According to various aspects, correct guidance in the first guide rail is understood to mean that the preforms are oriented horizontally and substantially in a radial direction. Correct guidance in the second guide rail is understood to mean that the preforms are guided in a vertical orientation. 
         [0011]    The piece goods or the preform usually have a longitudinal direction which at the same time may also be an axis of symmetry of the preform. The preform is pivoted by the turning device in such a way that the longitudinal direction itself is pivoted by a predefined angle, for example by 90°. It is thus possible to transfer the preform from a horizontal position to a vertical position. The apparatus may comprise a plurality of separating devices, wherein each of these separating devices is arranged after the turning device in the transport direction of the preforms. 
         [0012]    In the prior art, if any separating devices are provided at all, these are arranged in front of the turning unit. Furthermore, in the prior art, the turning unit is designed as a so-called closed unit, that is to say that the preform is already guided within the turning unit into an exact ordered position with respect to the guide rail, wherein it also cannot leave this position. By virtue of the inventive arrangement of the turning device upstream of the separating device, the turning unit itself can be configured freely, i.e. without a delimiting element which prevents any exit of the piece goods out of the guide rail. Due to the resulting possible configuration of the turning device, a higher throughput of the turning device can be achieved, so that a higher operating speed is possible in the region of the turning device, which is often an element that limits the operating speed. 
         [0013]    In one exemplary embodiment, the turning device is adjoined by a second guide rail, wherein the second guide rail likewise forms a gap through which one region of the piece goods passes and by means of which another region of the piece goods is held. According to various aspects, as mentioned above, the first guide rail and the second guide rail are rotated with respect to one another in such a way that the piece goods are conveyed in the vertical position in the second guide rail, whereas in the first guide rail they are conveyed in a horizontal position. According to some aspects, the second guide rail is formed by an outer circumference of the receiving surface. 
         [0014]    The apparatus as a whole may have a modular structure. It is thus possible for example for the preforms to be stored in a storage unit and then to be transported to the receiving surface by means of a conveying unit which is likewise designed as a module. By virtue of the modular structure, it is also possible for different units to be combined with one another. 
         [0015]    In a further exemplary embodiment, movement-promoting devices are provided along the second guide rail and promote the movement of the piece goods in the movement direction. It is thus possible for example for the piece goods to be conveyed by a directional flow of air, wherein suitable air flow nozzles may be arranged within the movement path of the piece goods or also outside said path. It would also be possible to promote the movement of the preforms by means of brushes, which may be arranged inside or outside the movement path, or also by means of followers arranged inside or outside. The edge of the receiving surface, which with particular preference is designed as a disc, could also be designed tribologically in such a way that the coefficient of friction between the piece goods and the receiving surface is increased so that the movement is accelerated. 
         [0016]    The apparatus according to the invention thus has a sorting region in which the preforms are first sorted. This sorting region merges directly into the turning device. Unsorted preforms are not separated out until the region of the second guide rail which adjoins the turning device (“settling section”). It is possible for one or more guide plates to be provided which are guided as far as a predefined region of the receiving surface or close to the latter. These guide plates may be adjoined by a retaining section, within which the preforms are prevented from sliding out of the guide rail in their longitudinal direction for example via a holding-down device above the mouth of the preforms. 
         [0017]    In addition, it is possible that a pre-sorting of the preforms, for example by means of second guide plate arranged in a circular manner, is carried out in the interior of the receiving surface. 
         [0018]    In a further exemplary embodiment, a conveying device such as a transport belt is provided which feeds the preforms to the receiving surface. In this case, a holding container for the preforms may be provided, from which the preforms are conveyed onto the receiving surface. 
         [0019]    In a further exemplary embodiment, the gap of the second guide rail is formed by an at least partially annular body, wherein at least one section of this annular body can be moved in a direction running radially with respect to the receiving surface. In the aforementioned second guide rail, several preforms may occasionally become stuck together. By radially displacing said section, the size of the gap can be increased in such a way that the preforms which are stuck together can drop downwards and thus be discarded. Only one design possibility for increasing the size of the gap for discarding purposes is specified here. However, other solutions are of course also conceivable. The point is merely that the size of the gap can be increased in order to eliminate disruptions by removing the preforms located in the region of the adjustable segment. By virtue of this displaceable outer segment, in particular in the region of the start of a holding-down device, disruptions caused by sticking together can thus be eliminated automatically without any intervention by the operator. According to various aspects, such disruptions are detected via light barriers or similar sensor devices. 
         [0020]    According to some aspects, a holding-down element is provided in at least one section of the second guide rail and prevents the piece goods from sliding out of the second guide rail in their longitudinal direction. In these regions of the holding-down element, the piece goods are thus held in a certain position with respect to the guide rail and can thus move essentially only along this guide rail. According to various aspects, all possible disruptions are already eliminated before this holding-down element, so that only those piece goods which lie in a certain way in the second guide rail slide below the holding-down element. 
         [0021]    In a further exemplary embodiment, the turning device is configured without a holding-down device, that is to say that in this case preforms which are not correctly ordered may also be present. 
         [0022]    In a further exemplary embodiment, the apparatus comprises at least one sensor device which detects a position of the piece goods with respect to at least one guide rail. By virtue of this sensor device, various incorrect arrangements of the piece goods with respect to the guide rail can be detected, such as for example tilted piece goods, piece goods which are stuck inside one another and the like. 
         [0023]    In a further exemplary embodiment, the apparatus comprises a feed device for feeding the piece goods to the receiving surface, wherein an end section of this feed device is spaced apart from the receiving surface by less than 300 mm, in some aspects by less than 200 mm, and in some aspects by less than 150 mm. The piece goods, that is to say in particular the preforms, are thus placed on the receiving surface at a relatively small distance therefrom, wherein the sorting process can also be aided by a suitably small falling height. According to various aspects, the preforms are fed to the receiving surface in a radial direction of the latter. With particular preference, the region of the feed device in which the preforms fall onto the receiving surface is arranged outside the geometric centre of the receiving surface, and the feed device runs as mentioned above substantially in the radial direction with respect to the receiving surface. 
         [0024]    In a further exemplary embodiment, the apparatus comprises a blowing-out device which blows a predefined portion of the piece goods out of the second guide rail. In this case, too, sensor devices can be used to ascertain that certain piece goods are not correctly located in the rail or that for example two preforms are stuck together. In this case, such incorrectly arranged piece goods can be blown upwards out of the second guide rail via the blowing-out device which may be arranged below the guide rail. 
         [0025]    The blowing-out device may be activated via sensor devices such as light barriers and an upstream valve. 
         [0026]    In a further exemplary embodiment, the speed of rotation of the rotatable receiving surface can be adjusted. In this way, the retained end of the piece goods in the region of the abovementioned holding-down element can be fixed by changing the speed of rotation of the receiving surface, or a control in principle of this retained end is possible by controlling the speed of rotation of the receiving surface, optionally also with a corresponding adjustment of a dispensing belt drive which conveys the piece goods onto the receiving surface. Both the speed of rotation of the receiving surface and also the conveying speed of the loading system for the preforms may thus be combined in the control system. 
         [0027]    The present invention also relates to an installation for sorting piece goods, comprising an apparatus of the type described above and also a synchronisation star wheel which is arranged downstream with respect to the movement direction of the piece goods and which picks up the piece goods from the apparatus. Via this synchronisation star wheel, the piece goods can be transferred individually to a further machine, such as a blowing machine for example. 
         [0028]    According to various aspects, a driven wheel is provided between the apparatus and the synchronisation star wheel and moves the piece goods at least partially. This may be a retaining wheel which aids the synchronisation. According to various aspects, the synchronisation star wheel is a sawtooth star wheel. In a further exemplary embodiment, the distance between the centre of this synchronisation star wheel and the apparatus, that is to say the outer circumference thereof, is less than 2000 mm and in some aspects less than 1500 mm. The aforementioned synchronisation star wheel is thus located in the direct vicinity of the receiving surface. 
         [0029]    In a further exemplary embodiment, a transfer rail is provided between the apparatus and the synchronisation star wheel, and provided on this transfer rail are a large number of air discharge openings which promote the movement of the piece goods. Via the aforementioned driven wheel and/or the transfer rail, a retaining pressure can be generated via a form fit and/or friction fit in front of the synchronisation star wheel. According to some aspects, the aforementioned transfer rail has air discharge openings both above and below the support ring of the corresponding preforms. In this case, the distance between that region in which the synchronisation star wheel comes into engagement with the preforms and the end of the aforementioned pressure shaft or the end of the last air discharge openings is less than 300 mm. In principle, however, it is sufficient to provide only a system which generates a retaining pressure in front of the synchronisation star wheel. 
         [0030]    The present disclosure also relates to a method for sorting piece goods and in particular preforms, wherein the piece goods are placed on a rotatable receiving surface and from there pass into a first guide rail. Furthermore, the piece goods are pivoted about their longitudinal direction by means of a turning device, and some of the sorted piece goods which are not guided in a predefined manner by the guide rails are separated out by means of at least one separating device. According to the disclosure, the piece goods pass firstly through the turning device and only then through the separating device. In the method according to the disclosure, therefore, as yet unsorted and thus also in some cases incorrectly oriented piece goods are also conveyed in the region of the turning device. By virtue of the method according to the disclosure, higher operating speeds can be achieved. A pivoting about the longitudinal direction is understood to mean that the piece goods are pivoted in their entirety, so that the orientation of the longitudinal direction changes as a result of the pivoting process. 
         [0031]    Further embodiments and advantages will emerge from the appended drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    In the drawings: 
           [0033]      FIG. 1  shows a plan view of an apparatus according to the invention; 
           [0034]      FIG. 2  shows an oblique view of the apparatus of  FIG. 1 ; 
           [0035]      FIG. 3  shows a detail view of a region of the apparatus of  FIG. 1 ; 
           [0036]      FIG. 4  shows a further detail view of the apparatus of  FIG. 1 ; 
           [0037]      FIG. 5  shows a detail view of the apparatus of  FIG. 1 ; 
           [0038]      FIG. 6  shows a detail view of the turning device; 
           [0039]      FIG. 7  shows a further detail view of the turning device; 
           [0040]      FIG. 8  shows a diagram of an installation according to the invention; 
           [0041]      FIG. 9  shows a side view of a transfer rail; 
           [0042]      FIG. 10  shows a further detail view of the installation of  FIG. 8 ; 
           [0043]      FIG. 11  shows a side view of one embodiment of the invention; and 
           [0044]      FIG. 12  shows a side view of a further embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0045]      FIG. 1  shows a plan view of an apparatus  1  according to the invention for sorting piece goods  10 . This apparatus  1  comprises a rotatable receiving surface  4  or receiving disc for the piece goods  10 . In the embodiment shown in  FIG. 1 , this receiving surface  4  rotates in the anticlockwise direction during operation, that is to say in the direction of the arrow P about the axis of rotation Dr. In one exemplary embodiment, it is possible that this receiving surface  4  has a curved profile, that is to say protrudes upwards in the centre and is lowered towards the edges. However, it would also be possible to configure this receiving surface  4  as a flat surface in another exemplary embodiment. If the receiving surface  4  is flat, one exemplary further development of the invention consists in arranging it horizontally, with it also being conceivable to arrange it at an angle with respect to the horizontal. One exemplary inclination is between about 5° and about 30° with respect to the horizontal. 
         [0046]    Via a feed device (not shown), the piece goods  10 , in this case therefore the preforms, are fed in an unsorted fashion to the receiving surface  4 . The receiving surface may be made from various materials, such as e.g. stainless steel or else alloys, or it may have an anti-friction coating such as e.g. a chromium-containing anti-friction coating. 
         [0047]    By virtue of the centrifugal force, the preforms  10  pass firstly to a first guide rail  6 , which is arranged here in a stationary manner and has a partially circular profile. The actual sorting process thus begins at the starting point denoted by reference A 1  and ends at the end point denoted by reference A 2 . The region between the points A 1  and A 2  is thus the sorting region A. In  FIG. 1 , all the preforms  10  are already correctly arranged with respect to the first guide rail  6 . This position may also be obtained due to the fact that the preforms have a centre of gravity which lies below the thread  10   b  of the preforms and thus results in an orientation in the radial direction in the manner shown in  FIG. 1 . 
         [0048]    Nonetheless, a considerable number of preforms will also arrive at the end point A 2  in an unsorted fashion. For instance, it is possible for a number of preforms to be stuck inside one another, or for the preforms not yet to be radially oriented or to be tilted to the side with respect to the first guide rail  6 . The first guide rail is arranged above the receiving surface  4  and a gap  9  is formed between the receiving surface  4  and the first guide rail  6 . 
         [0049]    The sorting region A is adjoined by a turning region B, in which the preforms are rotated by their longitudinal direction. The starting point of this turning region is denoted by reference B 1  and the end point is denoted by reference B 2 . Accordingly, reference  12  denotes the turning device. The turning region B is in turn adjoined by a settling section C, wherein the start of this settling section is denoted by reference C 1  and the end of the settling section is denoted by reference C 2 . In this region C, unsorted preforms  10  are also separated out.  FIG. 2  shows two separating devices in the form of separating plates  14 ,  15  which channel incorrectly arranged preforms radially inwards and thus feed them back to the first guide rail  6  and the sorting region A. These separating devices  14 ,  15  may have a straight region and a curved region. 
         [0050]    The separating region or the settling section C is adjoined by a retaining section D, the start of which is denoted by reference D 1  and the end of which is denoted by reference D 2 . Within this retaining section D, the preforms  10  are already sorted and are arranged in the desired position one behind the other. At the end of the retaining section D, that is to say after the point D 2 , the preforms  10  are passed to the above-mentioned synchronisation star wheel  34 . 
         [0051]    Reference  16  denotes the second guide rail, wherein this second guide rail has a gap  19  which is formed by a ring  18  and the outer circumference of the receiving surface  4 . Reference  22  denotes a segment of this ring  18  which can be moved radially outwards. 
         [0052]    Between the turning device  12  and the separating element  14 , there is a gap through which preforms  10  can pass outwards from the receiving surface  4  as a result of the centrifugal force. This gap is relatively small in  FIG. 1 . It may be designed to be larger or smaller by a different arrangement of the separating elements  14 ,  15 . 
         [0053]      FIG. 2  shows an oblique view of the apparatus shown in  FIG. 1 . It is possible to see here both the gap  9  which is formed between the receiving surface  4  and the first guide rail  6 . This gap  9  is formed here in a direction substantially perpendicular to the receiving surface. 
         [0054]    It is also possible to see the gap  19  which is formed by the second guide rail  16 . In addition, a holding-down element  24  is provided which holds down the individual containers  10  in a section between the points D 1  and D 2  of the second guide rail  16 . Besides the separating devices  14  and  15  shown in  FIG. 2 , a plurality of separating devices could also be provided. 
         [0055]      FIG. 3  shows a detail view of the second guide rail  16  in the region D in which the holding-down element  24  is provided. It can be seen that the holding-down element  24  is likewise in the shape of an annular segment and also has here a circular cross section. The holding-down element  24  is arranged above the preform  10  and thus prevents the latter from being able to slide in its longitudinal direction L out of the guide rail  16 . It can be seen that the preform is supported by its support ring  10   a  at one side with respect to the annular segment  18  and at the other side with respect to the receiving surface  4  and is guided in this way. 
         [0056]      FIG. 4  shows a further detail view of the apparatus  1  according to the invention in the region C. More specifically, this is a section in the region between the points C 1  and C 2  of  FIG. 1 , that is to say a region in which the holding-down element  24  is not yet present. Reference  27  denotes a blowing-out unit which is arranged below the guide rail and which is suitable for blowing any incorrectly positioned preforms  10  out of the guide rail  16 . By arranging the blowing-out device  27  in a region in which the separating device  15  is also arranged, the preforms  10  can be hurled away radially outwards with respect to the apparatus. 
         [0057]    According to various aspects, the apparatus also comprises a sensor device (not shown) which detects incorrect positions in relation to certain preforms  10  and outputs to the blowing-out unit  27  the corresponding signal to blow at least also this incorrectly oriented preform  10  out of the rail  16 . In this case, as shown in  FIG. 4 , this blowing-out device  27  is inclined with respect to the plane of the receiving surface  4 , so that the preform  10  tends to be hurled radially outwards. It would also be possible to provide a plurality of such blowing-out devices  27  one behind the other. 
         [0058]      FIG. 5  shows a further detail view of the apparatus according to the invention in the region C. It can be seen that the ring  18  which forms the second receiving rail  16  has a segment  22  which can be pushed outwards in the radial direction, that is to say in the direction of the arrow P 1 . During operation, it is possible for congestion or sticking-together to occur in particular in front of the holding-down element  24 . In order to eliminate this sticking-together, the segment  22  is pushed radially outwards and all of the containers  10  accumulated in this region can drop downwards out of the guide rail  16 . The segment  22  thus forms a discarding device in the same way as the blowing-out device  27  mentioned above. The segment  22  may be arranged in a transition region both in section C and in section D. 
         [0059]    The separating device  15  in front of the region of the holding-down element  24  may be guided almost as far as the upper face of the receiving surface  4 , in order to be able to feed superfluous or unsorted preforms  10  back to the sorting process. 
         [0060]      FIG. 6  shows the region B of an apparatus according to the invention, more specifically that section within which the preforms  10  are turned. It can be seen that the preforms  10  coming from the first guide rail  6  are still in a horizontal position, and then are tilted by approx. 90° in the region of the turning device and finally are located in the vertical position in the second guide rail  16 . As can be seen from  FIG. 6 , the turning device  12  has no holding-down elements, so that even incorrectly oriented preforms  10  can pass through it. 
         [0061]      FIG. 7  shows a detailed view of the turning device  12 . This turning device  12  has a protrusion  26  in the form of a flat plate, wherein this protrusion forms the radial contour which is used for turning the containers  10 . Also provided is a receiving region  127  which forms a contour perpendicular to the upper face of the receiving surface  4 . More specifically, this receiving region  127  defines the precise position of the protrusion  26  relative to the receiving surface  4 , so that on the one hand it is raised in terms of its height from right to left in  FIG. 7  and on the other hand likewise moves closer to the receiving surface  4  from right to left in the radial direction thereof. A three-dimensional contour of the protrusion  26  is obtained by fixing the protrusion or flat plate  26  to the receiving region  127 . 
         [0062]    By virtue of the protrusion  26 , an advantageous guidance of the preforms  10  in the turning device  12  may be achieved. 
         [0063]      FIG. 8  shows a plan view of an installation  30  according to the invention. Here, the apparatus  1  is no longer shown in detail. The apparatus  1  is adjoined firstly by a disc wheel  32  which rotates in the clockwise direction and in this way conveys the preforms  10  in the direction of a synchronisation star wheel  34 . This synchronisation star wheel  34  picks up individually the preforms  10  conveyed in the direction thereof and transfers said preforms to a downstream module, such as a blowing machine, a preform internal cleaning system, an inspection device or the like. 
         [0064]    The distance between the centre ZE of the synchronisation star wheel  34  and the outer circumference of the receiving surface  4  is in some aspects less than about 1500 mm, that is to say that the synchronisation star wheel  34  is arranged in the direct vicinity of the receiving surface  4 . 
         [0065]    Provided between the driven wheel  32  and the synchronisation star wheel  34  is a guide rail  33  which is shown in more detail in  FIG. 9 . Also within this guide rail  33 , the preforms  10  are conveyed at their support ring  10   a  by two protrusions  33   a  and  33   b  located opposite one another. Also provided within this transfer rail  33  are a large number of air discharge openings  36  which are likewise oriented in such a way that they convey the preforms  10  in the direction of the synchronisation star wheel. 
         [0066]      FIG. 10  shows a further detail view of a transfer region to the synchronisation star wheel  34 . It can be seen that the synchronisation star wheel  34  has recesses  35  in which individual preforms can be placed in each case. Also provided is an annular segment  38  which likewise serves for supporting the preforms  10 . 
         [0067]      FIG. 11  shows another embodiment of the invention, in which the preforms  10  are supplied on a dispensing belt  403  which is designed to revolve endlessly. The preforms  10  are conveyed by the dispensing belt  403  to a dispensing rail  404 , where they slide in the direction of the receiving surface  4  under the force of gravity. The receiving surface  4  is equipped with a drive unit  406  and is arranged at an angle  405  with respect to a horizontal. This angle is between about 5° and about 30°, and in some aspects between about 20° and about 25°. An advantage of this inclination with respect to the horizontal may be the positive assistance provided to the sorting process by a force of gravity component which acts on the preforms  10  as they move towards the first guide rail  6 . 
         [0068]    Another embodiment of the invention consists in configuring the receiving surface  4  in two parts, so as to form a central region  401  in the form of a disc and an outer region  401  in the form of a ring around the central region  402 . This configuration is shown in a side view in  FIG. 12 , wherein here the preforms  10  are again supplied by means of a dispensing belt  403  and a dispensing rail  404 . An advantage of this arrangement may be in the better controllability of the sorting process, since the central region  401  and the outer region  402  can be driven separately at different speeds and thus the sorting speed or sorting intensity can be controlled. The ability to be driven differently is provided by a drive unit  406  which is actively connected to the central region  401 , and a ring drive  407  which is actively connected to the outer region  402 . It may be advantageous if the outer region  402  is arranged at an angle with respect to the horizontal. The combination of the different drivability of the central region  401  and outer region  402  and the angled arrangement of the outer region  402  with respect to the horizontal may be advantageous. 
         [0069]    It will be apparent to those skilled in the art that various modifications and variations can be made to the apparatus for sorting performs and other bodies of the present disclosure without departing from the scope of the invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only.