Abstract:
A container-closing machine includes a central supporting column, a manipulation unit connected to the central supporting column, and a direct drive disposed between them. This drive produces reciprocal relative motion. The central supporting column defines an interior space containing the stator. The manipulation unit has a ring that defines an interior space with the rotor disposed therein. The ring and the column share a common axis of rotation that defines a radial plane perpendicular thereto along which the rotor and stator lie opposite each other and separated by a gap.

Description:
RELATED APPLICATIONS 
       [0001]    This application is the national stage entry under 35 USC 371 of PCT/EP2012/001668, filed on Apr. 18, 2012 which, under 35 USC 119, claims the benefit of the priority date of German application DE 10 2011 103 837.3, filed on Jun. 1, 2011 the contents of which are herein incorporated by reference. 
     
    
     FIELD OF DISCLOSURE 
       [0002]    The invention relates to a handling machine for containers, e.g. bottles, cans or the like, preferably a container closing machine, having at least one supporting column and at least one manipulation unit for the containers that is connected to the column, and having at least one direct drive with stator and rotor between the column and the manipulation unit to produce a reciprocal relative motion. 
       BACKGROUND 
       [0003]    A handling machine with direct drive between column and manipulation unit is disclosed by, for example, DE 10 2007 025 522 A1. Its primary aim is to reduce the costs, the design effort and the number of necessary components. 
         [0004]    Direct drives are also used in the case of rotary plates that are disposed on a turntable for aligning and/or equipping containers. An apparatus disclosed in WO 2005/115848 A2 is intended to enable the alignment or equipping of objects with little effort at high speed. In order to drive the rotary plates, use is made of the above mentioned direct drive, which requires no speed-reducing transmission members that are susceptible to wear between the associated motor output shaft and the rotary plate. This has proven its worth in practice. 
         [0005]    A drive for rotational machines having both a stationary and a rotating machine part is also known from WO 2008/022737 A1. A ring around the periphery of a machine part is provided. The ring includes a plurality of magnets. At least one corresponding stator covering only a partial segment of the ring is disposed on the other machine part. In this way the rotating machine part can be put into a defined rotation by an electromagnetic field generated by the stator. 
         [0006]    Quite independently of this, the procedure adopted with conventional handling machines or container closing machines, as presented in EP 1 647 518 A1 among others, is that a central column is connected mechanically and for power transmission to a head plate that, in turn, carries individual manipulation elements. The mechanical connection between these individual machine elements leads to a relatively voluminous mechanism having to be realized, resulting in problems of space and maintenance. Operations independent of one another are also impossible with a mechanical coupling of this nature. This is where the invention comes into play. 
       SUMMARY 
       [0007]    The invention is based on the technical problem of further developing such a handling machine for containers to the extent that an independent controlling of the relative motion between the column and the manipulation unit and, if applicable, between the manipulation unit and associated manipulation elements can be achieved in a simple and inexpensive way. A compact and low-maintenance design is also to be created. 
         [0008]    To resolve this technical problem a generic handling machine for containers within the context of the invention is characterized in that the stator of the (first) direct drive is disposed in the interior of the column and the rotor is disposed in the interior of a ring of the manipulation unit, with the ring encircling the column, or vice versa, and with the rotor and stator lying closely spaced opposite one another in a coincident radial plane. It is also self-evident that no power-transmitting elements are interposed between the rotor and the stator. 
         [0009]    Within the context of the invention, therefore, there is realized, first of all, a central direct drive that is generally accommodated in the interior of the column. It has in fact proven of value when the column is configured as a central hollow column, for then the stator or rotor respectively of the direct drive in question can be set into a wall. In this context it has also proven of value when the stator or rotor respectively set into the wall ends flush with a wall surface, and in particular with an outer wall surface, of the column. 
         [0010]    The manipulation unit generally comprises a head plate and the ring connected thereto on its underside. The ring in its turn may carry in its wall or flush with the inner wall surface the associated rotor or stator respectively on the manipulation unit. The configuration is again and advantageously selected so that the rotor or stator ends flush with a wall of the ring (the inner wall). 
         [0011]    The stator is usually located in the wall of the column that is configured as a central hollow column, and ends flush with the outer wall surface. The rotor on the other hand is located in the interior of the ring as part of the manipulation unit where it typically ends flush with the inner wall surface of the ring in question. The necessary distance between the stator on the one hand and the rotor on the other hand is automatically made available by the unavoidable spacing between, on the one hand, the outer wall surface of the bearing central column and, on the other hand, the inner wall surface of the ring, which at least partly encircles the head of the supporting column. This distance is typically of the order of a few millimeters. 
         [0012]    A continuous field (rotating field) generated in the stator, similar to the case of a linear motor, can in this way set up a rotary motion of the rotor with its iron magnets following the rotating field generated by the stator. As a consequence of this, the manipulation unit rotates about the supporting column having regard to an axis of rotation defined by the column, and at a rotational speed that is determined by the rotating field generated by the stator. It is again emphasized that stator and rotor can generally exchange positions. 
         [0013]    If the stator is in or on the column and if, like the column I,t is fixed in position, then the rotor that is attached in or to the ring of the manipulation unit will follow the rotary motion imparted to it by the stator. Basically however the manipulation unit with the ring can also be configured as fixed-position and in this case carry the stator. In this case the column with the rotor located on it, or in it, is now configured to rotate. While the latter variant is typically not implemented in practice, it is nonetheless possible of course and is covered by the invention. 
         [0014]    Of particular added significance is the fact that, as well as the already described first direct drive between the column and the manipulation unit, a second direct drive is provided between the manipulation unit and at least one manipulation element thereto connected. The manipulation element can be, but is not limited to, respective capping heads with whose aid a screw cap, for example, is screwed onto a bottle. The associated capping head is typically connected to a head plate in this case. The head plate with the ring connected to its underside forms overall the manipulation unit that, in the case of a container closing machine, may be configured as a capping ring. 
         [0015]    By having recourse to the first direct drive between column and manipulation unit and the second direct drive between manipulation unit and manipulation element or a plurality of manipulation elements, it is possible to configure both direct drives independently of one another. In fact the use of respective direct drives avoids a respective mechanical connection between the column and the manipulation unit and the manipulation unit and the manipulation element(s). As a result, the two direct drives can be configured independently of one another and each can be self-dependently controlled/regulated individually or both together. 
         [0016]    The second direct drive too is advantageously configured with a stator as well as a rotor. The stator is typically connected to the manipulation unit. The rotor, on the other hand, is connected to the manipulation element or to the plurality of manipulation elements. The desired relative motion between the manipulation unit on the one hand and the manipulation element(s) on the other hand is again made available in this way. The reverse procedure can generally be adopted as well, in which case the rotor is provided on the manipulation unit while the stator is located on the manipulation element. 
         [0017]    So that the two direct drives described above do not influence one another by their respectively generated electromagnetic (rotating) fields, it has proven to be of value when the two direct drives are axially disposed at a distance from one another. Indeed the stator and the rotor of the second direct drive also lie spaced a short distance apart from one another in a coincident radial plane and with no interposed power transmission elements. This means that the configuration is selected comparably to the case of the first direct drive. In both cases the stator and the rotor are each disposed in a radial plane relative to the central column. In order now to realize the already described axial spacing of the two direct drives in detail, it is proposed that the two direct drives, with their associated stators and rotors, be each disposed radially relative to the central column in radial planes axially spaced relative to each other. The axial distance of the radial planes is typically configured as being greater than or equal to the radial distance of the respective direct drive from the central column. 
         [0018]    This means that the stator and rotor of the respective direct drive exhibits an associated radial distance away from the central column. It has generally proven to be an advantage when the radial distance of stator and rotor of the first direct drive is configured to be less than or equal to the radial distance of the second direct drive. The axial distance of the two radial planes spanned by the direct drives is now typically configured to be greater than or equal to the (lesser) radial distance of the first direct drive. 
         [0019]    According to another advantageous embodiment it has proven of value if a plurality of manipulation elements are provided on the periphery of the manipulation unit. The individual manipulation elements are typically acted upon in common along a cam by the second direct drive. In a further advantageous embodiment, it is moreover conceivable for one or more manipulation elements to be each equipped with single drives, with the respective single drive advantageously providing a vertical motion and/or rotary motion of the associated manipulation elements. 
         [0020]    In this way the first direct drive can, in the first instance, act on the manipulation unit relative to the column with a relative motion that can be controlled/regulated. This means that the capping ring, which is usually realized at this point, can be acted upon relative to the central column using the first direct drive with a speed that can be controlled and/or regulated. 
         [0021]    The individual manipulation elements or capping heads can be activated independently of this. This happens with the aid of the second direct drive. This second direct drive, if necessary in connection with the cam, ensures that the individual manipulation elements are acted upon with a speed that can be controlled or regulated irrespective of the motion of the manipulation unit relative to the central column. Finally, the cam can now also be wholly or partly replaced by the single drives. As a result, each individual manipulation element can theoretically be acted upon in a way that can be controlled or regulated independently of, for example, a neighboring manipulation element in regard to its motion. 
         [0022]    Like the one or the two direct drives, the column and the manipulation unit are each advantageously configured rotationally symmetrically to a common and coincident central axis. The central axis corresponds typically to the central axis of the cylindrically configured column and hence to the axis of rotation of the manipulation unit relative to the column. A controller is also advantageously provided. This controller preferably serves the independent triggering of the first and the second direct drive. In this way the first direct drive can be driven with a peripheral speed of the head plate relative to the column. Independently of this, a rotational/capping speed of the associated manipulation elements or capping heads can be set using the second direct drive. The controller may also trigger the respective single drive or drives. 
         [0023]    The result is that a handling machine for containers is described and presented in which the first direct drive or main drive between the column and the manipulation unit that is rotatably connected to it on the one hand, and the drive for the manipulation elements or capping heads on the other hand, are uncoupled from one another. This is all achieved taking into account a structure that is not susceptible to malfunction and having compact dimensions at the same time. In connection with the independent controlling or regulating of the respectively deployed direct drives, a universally functioning handling machine is provided which has so far remained unequaled in this embodiment and consistency. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The invention is explained more fully below by reference to the detailed description and the accompanying figures, in which: 
           [0025]      FIG. 1  shows the inventive handling machine for containers in a first variant, 
           [0026]      FIG. 2  shows the object of  FIG. 1  in a modification, and 
           [0027]      FIG. 3  shows the object of  FIG. 1  and  FIG. 2  in a further third version of the embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    The figures depict a handling machine for containers  1 . Containers  1  may be, \ but are not limited to being, plastic bottles and in particular PET bottles. The handling machine is configured in the present case as a container closing machine. Screw caps  2  are screwed onto associated bottles  1  for this purpose. This is done with the aid of manipulation elements  3  that, in the present case, are configured as capping heads  3 . Manipulation elements  3  are circumferentially arranged on a head plate  4  that, together with a ring  5  connected to the underside of head plate  4 , altogether defines a manipulation unit  4 ,  5 . 
         [0029]    Manipulation unit  4 ,  5  is mounted so as to be able to rotate about an axis of rotation R on a supporting column  6 . In the particular embodiment described herein, and without limitation, supporting column  6  remains fixed in position whereas manipulation unit  4 ,  5  rotates about axis of rotation R. The same applies to the manipulation elements or capping heads  3  and bottles  1 . 
         [0030]    Supporting column  6  is designed as a central hollow column and configured to be essentially cylindrical. Supporting column  6  and manipulation unit  4 ,  5  are each configured to be rotationally symmetrical relative to axis of rotation R or to central axis R, which coincides with axis of rotation R. This also applies to a first direct drive  7 ,  8  as well as to a second direct drive  9 ,  10  to be described in more detail hereinafter. 
         [0031]    First direct drive  7 ,  8  is equipped with a stator  7  and a rotor  8  and disposed between column  6  and manipulation units  4 ,  5  in order to generate a reciprocal relative motion. For this purpose, stator  7  of first direct drive  7 ,  8  is disposed in the interior of column  6 , while rotor  8  is placed in the interior of ring  5  of manipulation unit  4 ,  5  with the ring encircling column  6 . Basically the inverse to this described arrangement may also be adopted although this is not depicted in detail. 
         [0032]    Stator  7  finishes flush with the outer wall surface of column  6 . Rotor  8  on the other hand is let flush into the inner wall surface of ring  5 . The short distance of a few millimeters between the outer wall surface of column  6  and the inner wall surface of ring  5  also determines the distance between the two surfaces of stator  7  and rotor  8 . This distance is also on the order of a few millimeters. 
         [0033]    Respective direct drives  7 ,  8  and  9 ,  10  are drives that operate on a purely electromagnetic basis and without interposed power-transmission elements between respective stators  7 ,  9  and rotors  8 ,  10 , or which do not have recourse to such power-transmission elements. Instead, stator  7  and rotor  8  are located in a coincident radial plane E 1  for first direct drive  7 ,  8 . In the case of second direct drive  9 ,  10  again, stator  9  there located and rotor  10  are arranged in a coincident radial plane E 2 . The two radial planes E 1  and E 2  each extend along a radius relative to the coincident axis or axis of rotation R. Stator  7 ,  9  and its associated rotor  8 ,  10  are also radially separated by a short distance from each other, which is typically within the range of a few millimeters. 
         [0034]    First direct drive  7 ,  8  is arranged between column  6  and manipulation unit  4 ,  5 . Second direct drive  9 ,  10 , on the other hand, is located between manipulation unit  4 ,  5  and the one or plurality of manipulation elements  3  connected to manipulation unit  4 ,  5 . The two direct drives  7 ,  8  and  9 ,  10  are configured independently of one another and can be self-dependently controlled/regulated either individually or both together. For this purpose, there is provided a controller  11  that serves to act on respective direct drives  7 ,  8 ;  9 ,  10 . 
         [0035]    The two direct drives  7 ,  8 ;  9 ,  10  are each arranged with their associated stators  7 ,  9  and rotors  8 ,  10  radially relative to central column  6  and radially to axis of rotation R. The two direct drives  7 ,  8 ;  9 ,  10  are also located in radial planes E 1 , E 2  that are axially spaced apart from one another. The two radial planes E 1  and E 2  are in fact axially spaced apart from one another by amount A. 
         [0036]    This axial distance A between the two radial planes E 1  and E 2  is typically greater than or equal to a radial distance B 1 , B 2  between respective direct drive  7 ,  8 ;  9 ,  10  and central column  6  or its axis of rotation R. In the embodiment described herein, this radial distance B 1  is configured to be less than radial distance B 2  between a second direct drive  9 ,  10  relative to the coincident axis of rotation R. In other words: 
         [0000]      B1&lt;B2 
         [0037]    Also, the following applies to axial distance A of radial planes E 1 , E 2 : 
         [0000]      A&gt;B1. 
         [0038]    In other words, axial distance A of radial planes E 1 , E 2  is greater than or equal to the least radial distance B 1  of associated direct drive  7 ,  8  relative to central column  6  or the latter&#39;s axis of rotation R. It goes without saying that the above-reproduced dimensioning rules apply to the depicted embodiment by way of example only and do not generally limit the invention. 
         [0039]    The manipulation elements or capping heads  3  provided on the periphery of head plate  4  can be acted upon by a common cam  12 . Like central column  6 , cam  12  is generally configured to be fixed in position. In this way, cam  12  is followed by the manipulation elements or capping heads  3  as they rotate about axis of rotation R. Because cam  12  exhibits a more or less sinusoidal course in the case of the example, the capping heads or manipulation elements  3  execute a stroking motion when rotationally displaced along cam  12 . 
         [0040]    These different positions of manipulation element  3  or of the respective capping head can be seen from a comparison between the right-hand and left-hand representation in  FIGS. 1 and 2  which belong to different radial positions of manipulation element or capping head  3  along the described rotary motion relative to cam  12 . To this stroking motion is then added a screwing motion for capping heads or manipulation elements  3  that, in the context of the embodiment according to  FIGS. 1 and 2 , is produced by capping heads  3  being driven to rotate by a gear wheel  14  against ring  5 . In the embodiment according to  FIG. 3 , a single drive  13  as a substitute for cam  12  and for gear wheel  14  makes for a combined stroking/screwing motion of respective capping head or manipulation element  3 . 
         [0041]    In either instance, capping heads or manipulation elements  3  execute a combined stroking/screwing motion with whose aid screw caps  2  are screwed onto bottles  1 . Respective single drive  13 , as indicated in  FIG. 3 , may also be provided alternatively to cam  12  corresponding to the two embodiments according to  FIG. 1  and  FIG. 2 . The vertical motion and/or rotary motion of related and associated manipulation element or capping head  3  can be controlled with the aid of this single drive  13 . All of this is achieved with the aid of controller  11  and is not shown in detail. 
         [0042]    First direct drive  7 ,  8 , as well as second direct drive  9 ,  10 , and of course the last-described single drive  13  as well, can be controlled and/or regulated independently of one another with the aid of controller  11 . Manipulation elements  3  can execute an independent motion from associated manipulation unit  4 ,  5  in this way. Similar considerations apply to manipulation unit  4 ,  5  in regard to column  6 , which carries it, by contrast with manipulation elements  3 . 
         [0043]    The peripheral speed of head plate  4  relative to central column  6 , is in fact, determined with the aid of first direct drive  7 ,  8 . As a result of this, manipulation elements or capping heads  3  execute the described stroking motion as ring  5  rotates relative to fixed-position cam  12 . At the same time, the rotary motion of ring  5  through gear wheel  14  drives, at least section by section, associated manipulation element or capping head  3 . As a result of this, manipulation elements or capping heads  3  execute the desired rotary/capping motion (cf.  FIG. 1 ). 
         [0044]    In the variant according to  FIG. 2 , first drive  7 ,  8  again determines the peripheral speed of head plate  4  relative to central column  6 . In this variant however, manipulation elements or capping heads  3  are not coupled to the motion of ring  5  and can be acted upon with the desired screwing motion independently thereof. In other words, the stroking motion of manipulation elements or capping heads  3  is again, as in the case of the embodiment according to  FIG. 1 , determined with the aid of first direct drive  7 ,  8 . In the case of the variant according to  FIG. 2  on the other hand, second direct drive  9 ,  10  now ensures that manipulation elements or capping heads  3  perform a screwing motion that is independent thereof. The combination of the two motions, namely the stroking motion with the aid of first direct drive  7 ,  8  and the screwing motion with the aid of second direct drive  9 ,  10 , again leads to the desired rotational/capping motion or rotational/screwing motion of associated manipulation element or capping head  3 . In the context of  FIG. 2  it is alternatively conceivable for cam  12  to be replaced by a single drive  13  (not shown) that acts upon the respective manipulation element or capping head  3  with the desired linear motion. This is not shown though. 
         [0045]    The embodiment according to  FIG. 1  is equipped with first direct drive  7 ,  8  only, whereas the connection of ring  5  with associated manipulation element  3  is made conventionally with the aid of an interposed gear wheel  14 . As soon as first direct drive  7 ,  8  sets ring  5  in rotation, this rotary motion about axis of rotation R ensures that respective manipulation element  3  that is connected in a meshing manner with ring  5  via gear wheel  14  also performs a rotary motion that, in conjunction with associated cam  12 , produces the desired stroking/rotary motion, i.e. altogether the screwing motion for screw cap  2 . 
         [0046]    In the case of the variant according to  FIG. 2 , ring  5  is not directly coupled to respective manipulation element  3 . Instead the respective manipulation element has its own rotating drive, which is made available by second direct drive  9 ,  10 . The stroking motion of manipulation element  3  is again produced by first direct drive  7 ,  8  and defined with the aid of cam  12 . In this way, individual manipulation elements  3  can be triggered independently of the motion of head plate  4  relative to column  6  in its combined screwing motion in the context of this embodiment. 
         [0047]    Finally and for the sake of completeness, the variant according to  FIG. 3  resorts not to cam  12  according to  FIGS. 1 and 2  but instead to respective single drive  13 , which is assigned to respectively associated manipulation element  3 . The combined vertical/rotary motion of screw cap  2  is generated with the aid of single drive  13  and independently of the peripheral speed of head plate  4  and independently also of the rotary motion of capping heads  3 .