Abstract:
There is disclosed a labelling machine for applying sleeve labels on respective articles, comprising: a conveyor movable along a path comprising, in turn, a first inlet station for the articles still to be labelled and a second outlet station for the labelled articles; the conveyor comprises a handling device adapted to displace at least one first of the sleeve label and the article still to be labelled along a first segment of the path, so as to insert the article still to be labelled within the sleeve label; the conveyor also comprises a positioning device adapted to actively position a second of the sleeve label and the article in a desired position with respect to the first of the article and the sleeve label along a second segment of the path; the first segment is comprised within the second segment.

Description:
PRIORITY CLAIM AND RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority under 35 U.S.C. Section 119 to Italian Patent Application Serial No. TO2012A 000463, filed on May 28, 2012, which Application is incorporated herein by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The present document relates to a labelling machine and a method for applying sleeve labels on respective articles, in particular containers for pourable products. 
       BACKGROUND 
       [0003]    The application of sleeve labels on containers filled with pourable food products is known in the field of labelling. 
         [0004]    The above said sleeve labels are obtained by: 
         [0005]    cutting a plurality of flat rectangular or square labels from a tape which is unwound from a reel; 
         [0006]    overlapping, by folding, the opposite vertical edges of each cut label so as to form a respective sleeve label; and 
         [0007]    welding the opposite edges of each label. 
         [0008]    Patent application WO-A-018806, in the name of the same Applicant, discloses, for example, labelling machines, in which each sleeve label is first formed on a respective sleeve drum, and then transferred on a relative container, for example by inserting the latter within the corresponding sleeve label. 
         [0009]    The above said labelling machines of the known type substantially comprise: 
         [0010]    a carousel rotatable about a first axis arranged, in use, vertically; and 
         [0011]    a plurality of carrying units for respective containers, arranged along a circumferential edge of the carousel and rotated about the first axis of the carousel along a labelling path. 
         [0012]    Each carrying unit is also fed with a relative container to be labelled at an inlet station of the labelling path and provides the relative container on which the sleeve label has been applied at an outlet station of the labelling path. 
         [0013]    Proceeding from the inlet station to the outlet station along the labelling path, each carrying unit is also fed with a relative flat label, forms a relative sleeve label and applies this sleeve label to the relative container. 
         [0014]    Each carrying unit also comprises a lower support element adapted to support a lower wall of the relative container and an upper retaining device adapted to cooperate with an upper portion of the relative container to retain it in a vertical position during the rotation of the carousel about the first vertical axis. 
         [0015]    Each support element comprises, in turn: 
         [0016]    a tubular upright, which is fixed to a horizontal plane rotatable of the carousel; and 
         [0017]    the cylindrical sleeve drum, which engages the relative tubular upright in a rotatable and axially sliding manner with respect to a second axis. 
         [0018]    In particular, the sleeve drum supports a relative container on its upper surface. 
         [0019]    Each sleeve drum is also mobile under the control of a cam, between: 
         [0020]    a totally lowered position reached at the inlet and outlet station of the conveying path; and 
         [0021]    a lifted position reached between the inlet and the outlet stations of the conveying path. 
         [0022]    Each sleeve drum also comprises a pneumatic driving device formed by a vacuum source and a plurality of suction holes arranged on its side surface and connectable selectively with the vacuum source. 
         [0023]    In the totally lowered position, the sleeve drum is substantially contained within the upright to allow the container to enter or exit on/from the carousel. 
         [0024]    In the lifted position, each sleeve drum projects from an upper surface of the relative support element and is adapted to receive a respective flat label on its side surface. 
         [0025]    The sleeve drum also rotates about its second axis to allow the flat label to be completely wound about the sleeve drum until it reaches a tubular configuration, in which the opposite vertical edges thereof overlap. 
         [0026]    More precisely, during the winding of the label, the driving device is actuated so as to retain the label on the side surface of the sleeve drum in virtue of the action of vacuum. 
         [0027]    Each carrying unit finally comprises a welding bar adapted to longitudinally weld the overlapped edges of the relative sleeve label. 
         [0028]    Once the welding of the overlapped edges of the sleeve label is completed, the driving device is switched off and the sleeve drum is returned to the lowered position within the upright. 
         [0029]    Accordingly, the sleeve label is released from the side surface of the sleeve drum, is retained above the upright by an upper annular edge of the upright, and finally is slidingly engaged by the relative container. 
         [0030]    At the outlet of the carousel, the containers are fed in a substantially vertical position by a conveying device through a heating device adapted to shrink the labels about the bottles. 
         [0031]    Since the sleeve labels are fed through the heating device always in contact with a resting plane defined by the above mentioned conveying device, the known labelling machines of the above disclosed type have some drawbacks mainly resulting from the fact that such machines do not allow to selectively control the position of the sleeve labels along the relative containers and therefore have a relatively low flexibility. 
         [0032]    A similar solution is also known from WO2010/040397 in the name of the same Applicant. 
         [0033]    In order to selectively control the position of the sleeve labels along the relative containers, the same Applicant has proposed in patent application PCT/IB2011/055591 a labelling machine comprising: 
         [0034]    a carousel of the above disclosed type, which provides containers with the relative sleeve labels in a first position; and 
         [0035]    an additional module fed by the carousel and adapted to displace the sleeve labels in a second position with respect to the relative container. 
         [0036]    More precisely, the module comprises: 
         [0037]    a further carousel rotatable about a third axis; 
         [0038]    a plurality of further carrying units for respective containers arranged along a circumferential edge of the further carousel and rotated about the third axis by the further carousel; and 
         [0039]    a plurality of transfer devices arranged along a circumferential edge of the further carousel, associated with respective carrying units and adapted to displace respective sleeve labels along relative fourth axes parallel to the third axis with respect to the corresponding containers. 
         [0040]    In greater detail, each further carrying unit comprises: a plate adapted to support the lower wall of the relative container, and a retaining element mobile between a lifted position in which it allow the entry and exit of the container on/from the module and a lowered position in which it cooperates with an upper portion of the relative container. 
         [0041]    Each transfer device is mobile in parallel to the respective fourth axis and comprises a surface provided with a plurality of holes connectable to a vacuum source to retain the relative sleeve label and move the latter from the respective first to the respective second position. 
         [0042]    The need is felt in the field to selectively control the position of the sleeve labels along the relative containers with a labelling machine as simple as possible. 
         [0043]    Furthermore, the sleeve labels still have not been subjected to any thermal retraction when they are transferred from the carousel to the module, in the solution shown in patent application PCT/IB2011/055591. 
         [0044]    Therefore, the labels have not yet been stably fixed to the relative containers when they reach the module. 
         [0045]    Therefore, the solution shown in patent application PCT/IB2011/055591 does not allow to control the angular position of each sleeve label with respect to its axis, i.e. to ensure a predetermined angular orientation with respect to an axis of the container. 
         [0046]    The need is therefore felt in the field to apply the sleeve labels on the respective containers in a desired angular position. 
         [0047]    EP-547754 discloses a labelling machine, in which containers to be labelled are inserted within respective sleeve labels. 
         [0048]    More precisely, as the containers move, respective sleeve labels are at first retained in a given position and then move together with respective containers. 
         [0049]    DE-A-19716079 discloses a labelling machine, in which the sleeve labels move towards respective containers and are inserted onto respective containers at respective given prescribed positions. 
         [0050]    More precisely, the labelling machine comprises a plurality of grippers which both move the respective labels relative to corresponding containers and apply those respective labels onto corresponding containers at respective prescribed positions. 
       Overview 
       [0051]    Examples of the present subject matter provide a labelling machine, which satisfies at least one of the above cited needs in a simple and cost-effective manner. 
         [0052]    The aforementioned is achieved by the present subject matter as it relates to a labelling machine for applying sleeve labels on relative containers, as defined in claim  1 . 
         [0053]    The present subject matter also relates to a method for applying sleeve labels on relative containers, as defined in claim  14 . 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0054]    Two embodiments are hereinafter disclosed for a better understanding of the present subject matter, by way of non-limitative example and with reference to the accompanying drawings, in which: 
           [0055]      FIG. 1  shows a diagrammatic plan view of a labelling machine according to the dictates of the present subject matter, with parts removed for clarity; 
           [0056]      FIG. 2  shows a plan view on an enlarged scale of first components of the labelling machine of  FIG. 1 , with parts removed for clarity; 
           [0057]      FIG. 3  shows a plan view on a further enlarged scale of the first components of the labelling machine of  FIGS. 1 and 2 ; 
           [0058]      FIG. 4  shows a perspective view on a strongly enlarged scale of second components of the labelling machine of  FIGS. 1 and 2 ; 
           [0059]      FIG. 5  is a section taken along line V-V of  FIG. 4 , with parts removed for clarity; 
           [0060]      FIG. 6  shows a perspective view on a strongly enlarged scale of third components of the labelling machine of  FIGS. 1 and 2 ; 
           [0061]      FIG. 7  is a section taken along line VII-VII of  FIG. 6 ; and 
           [0062]      FIGS. 8 to 10  show respective subsequent steps of the operation of the labelling machine of  FIGS. 1 and 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0063]    With reference to  FIGS. 1 and 2 , numeral  1  indicates a labelling machine for applying sleeve labels  2  on respective articles, in particular containers  3  intended to be filled with a pourable food product. 
         [0064]    As shown in  FIGS. 8 to 10 , each container  3  is elongated along an axis A, is defined by a lower wall  5  orthogonal to axis A and comprises a neck portion  4  coaxial to axis A. 
         [0065]    In particular, machine  1  comprises: 
         [0066]    a conveyor  6  and an inlet star-wheel  11 ; 
         [0067]    a carousel  7  rotatable about a circular path P having axis B, fed by conveyor  6  with containers  3  still to be labelled and adapted to provide labelled containers  3 ; 
         [0068]    a labelling module  9  adapted to feed carousel  7  with a sequence of flat labels  10  intended to form respective sleeve labels  2 ; and 
         [0069]    an outlet conveyor  8  and an outlet star-wheel  12 . 
         [0070]    In detail, conveyors  6 ,  8  are of the Archimedean screw type and feed containers  3  along respective linear paths Q 1 , Q 2 . 
         [0071]    Starwheels  11 ,  12  are rotatable about respective axes parallel to axis B and are tangent to carousel  7  respectively in stations I, O. 
         [0072]    In particular, starwheel  11  is interposed between conveyor  6  and carousel  7 ; and starwheel  12  is interposed between carousel  7  and conveyor  8 . 
         [0073]    Labelling module  9  substantially comprises a drum  13  rotatable about an axis thereof parallel to axis B. 
         [0074]    In greater detail, carousel  7  comprises ( FIG. 2 ) a plurality of carrying units  20  angularly equally spaced about axis B, mounted on a peripheral edge of carousel  7 , and fed by carousel  7  along path P. 
         [0075]    Path P comprises: 
         [0076]    a conveying segment R of containers  3  extending between stations I, O and between starwheels  11 ,  12 ; and 
         [0077]    a return segment S extending between stations I, O and between starwheels  11 ,  12 . 
         [0078]    Each container  3  is arranged in a lowered position at stations I, O of path P. 
         [0079]    With reference to each container  3  displaced by a relative carrying unit  20 , segment R comprises, proceeding from station I towards station O, ( FIG. 1 ): 
         [0080]    an arc α, along which container  3  is displaced from the relative lowered position to a lifted position; 
         [0081]    a station T, at which drum  13  transfers flat labels  10  to carrying unit  20  of carousel  7 ; 
         [0082]    an arc β for forming sleeve label  2  from respective label  10  ( FIG. 8 ); 
         [0083]    an arc γ for welding sleeve label  2 ; and 
         [0084]    an arc ε, along which container  3  is displaced from the lifted position to the lowered position, so as to insert container  3  within sleeve label  2  ( FIG. 10 ). 
         [0085]    With reference to  FIGS. 4 and 5  and from  8  to  10 , each carrying unit  20  comprises: 
         [0086]    support unit  21  adapted to support wall  5  of respective container  3 ; and 
         [0087]    a retaining device  28  ( FIG. 5 ) adapted to cooperate with neck portion  4  of respective container  3 . 
         [0088]    In particular, support unit  21  of each carrying unit  20  comprises in turn: 
         [0089]    a hollow upright  22  elongated along axis C parallel to axis B and fixed to a horizontal plane  29  rotatable about axis B of carousel  7 ; and 
         [0090]    a hollow sleeve drum  23 , mounted rotatably about axis C and sliding about axis C on respective upright  22 , and 
         [0091]    a plate  29  ( FIG. 5 ) borne by sleeve drum  23  and defining an upper surface  24 , orthogonal to axis C and adapted to support respective container  3 . 
         [0092]    Unit  21  of each carrying unit  20  also comprises a bearing  31  interposed between relative plate  29  and relative sleeve drum  23 . 
         [0093]    Bearing  31  makes plate  29  and sleeve drum  23  integral along axis C whereas it makes drum  23  angularly mobile about axis C with respect to plate  29 . 
         [0094]    Each sleeve drum  23  defines a cylindrical side surface  25  having axis C and adapted to cooperate with a respective flat label  10  and corresponding sleeve label  2 . 
         [0095]    Each sleeve drum  23  is also mobile along axis C and integral with plate  29  under the control of a cam interacting with relative cam follower  26  ( FIG. 4 ) borne by respective carrying unit  20 , between a relative position which is completely retracted in which it is housed together with plate  29  within respective upright  22  and a relative lifted position. 
         [0096]    Each sleeve drum  23 , when arranged in a totally retracted position, is completely housed within relative upright  22  so that surface  24  of relative plate  29  is at the same level and therefore coplanar with upper surface  27  of relative upright  22 . 
         [0097]    Each sleeve drum  23 , when arranged in the lifted position, projects from surface  27  of relative upright  22  and is adapted to receive, on its surface  25 , a relative label  10  from sleeve drum  13  at station T of path P. 
         [0098]    More precisely, each label  10  is transferred from drum  13  to sleeve drum  23  at a distance H from surface  27  of relative upright  22  ( FIG. 8 ). 
         [0099]    Following the interaction of each cam follower  26  with the cam (not shown), each sleeve drum  23 : 
         [0100]    is displaced from the respective totally retracted position to the lifted position along arc α of segment R, so as to determine the lifting of plate  29  and container  3  along relative axis C; 
         [0101]    remains in the respective lifted position along the portion of segment R interposed between art α and arc ε; and 
         [0102]    is displaced from the respective lifted position to the totally retracted position along arc ε of segment R, so as to determine the lowering of relative plate  29  and container  3  along relative axis C. 
         [0103]    Flat labels  10  are cut in a known manner from a tape by means of a cutting device (not shown) and fed to drum  13  so as to subsequently be fed to relative sleeve drums  23 , at station T of path P. 
         [0104]    In detail, cut labels  10  are retained, by means of the action of vacuum, on a side surface of drum  13 , along arc β of segment R of path P. 
         [0105]    More in particular, surface  25  of each sleeve drum  23  comprises a plurality of through-holes  30  ( FIG. 5 ) adapted to exert a suction action on relative label  3 , along arc β of path P and adapted not to exert any suction action in the remaining portion of path P. 
         [0106]    Each sleeve drum  23  rotates, in a manner known per se, about relative axis C along arc β of segment R of path P, under the action of a relative actuator  81  which is diagrammatically shown in  FIG. 4 . 
         [0107]    Thereby, each label  10  exiting from drum  13  is totally wound about surface  25  of relative sleeve drum  23 , so as to form a relative cylinder with opposite respective vertical edges  32  overlapped to one another (Figures from  8  to  10 ), along arc β of segment R of path P. 
         [0108]    It should be noted that each label  10  and corresponding sleeve label  2  are maintained at the same distance H from surface  27  of relative upright  22 , along arcs β, γ of segment R of path P. 
         [0109]    As shown in  FIGS. 8 to 10 , device  28  of each carrying unit  20  comprises in a known manner a cylindrical element  35  protruding from a horizontal plane (not shown) of carousel  7  rotatable about axis B. 
         [0110]    Element  35  of each carrying unit is mobile in parallel to relative axis C and has a free portion  36  configured, in the case shown, like a bell and adapted to cooperate with neck portion  4  of relative container  3  borne by corresponding unit  21 . 
         [0111]    More in particular, the displacement parallel to relative axis C of each element  35  is controlled so that the distance between its free portion  36  and surface  24  of plate  29 : 
         [0112]    is constant, during the displacement of relative carrying unit  20  along segment R of path P; and 
         [0113]    increases at stations I, O of path P and during segment S of path P. 
         [0114]    Thereby, containers  3  are held firmly in the respective vertical positions along segment R of path P, and can be transferred freely from starwheel  11  to station I and from starwheel  12  to station O. 
         [0115]    Each carrying unit  20  finally comprises a relative welding device  40  (diagrammatically shown in  FIG. 1 ) adapted to cooperate with label  10  wound on sleeve drum  23  so as to weld edges  32  overlapped to one another and form sleeve label  2 , at arc γ of segment R. 
         [0116]    Advantageously, carousel  7  comprises a plurality of positioning devices  50  adapted to actively position sleeve labels  2  in respective desired positions with respect to corresponding container  3 , along an arc μ of path P, which comprises arc ε. 
         [0117]    By the term “actively position” there is intended, in the present description, that the positioning devices  50  are adapted to hold sleeve labels  2  in the respective desired positions against the force of gravity. 
         [0118]    In the case shown, positioning devices  50  are adapted to maintains sleeve labels  2  at relative distances H from surface  27  of relative upright  22  ( FIG. 9 ), when respective sleeve drums  23  move integrally with corresponding containers  3  from the relative lifted positions to the relative totally retracted positions along arc ε of segment R. 
         [0119]    Thereby, by adjusting transfer distance H of labels  10  from drum  13  to relative sleeve drums  23 , the final position for applying sleeve labels  2  on respective containers  3  can be adjusted, as may be seen in  FIG. 10 . 
         [0120]    Labelling machine  1  also includes: 
         [0121]    a display system  84  ( FIG. 1 ) adapted to control the angular position of each container  3  with respect to relative sleeve label  2  and about axis C, while the relative carrying unit  20  moves along an arc a arranged downstream of arc γ and upstream of arc ε of segment R with reference to the feeding direction of containers  3  along segment R; and 
         [0122]    an arc heater  85  adapted to heat, by blowing hot air, sleeve labels  2  arranged in the desired position so as to induce the partial thermal retraction of sleeve labels  2  on containers  3 , along an arc ψ arranged immediately downstream of arc ε of segment R and upstream of station O, with reference to the feeding direction of containers  3  along segment R. 
         [0123]    Display system  84  is also configured to control actuators  81  so as to determine further rotations of sleeve drums  23  with respect to plates  29  about relative axes C, along arc ∂ of segment R. 
         [0124]    Heater  85  is borne by a fixed portion (not shown) of machine  1  and is thus stationary with respect to axis B. 
         [0125]    Positioning devices  50  are adapted to lock sleeve labels  2  along arc μ of path P and to let the above said sleeve labels  2  free along an arc ν of path P. 
         [0126]    More in particular, arc μ extends from a station V up to station O of path P whereas arc ν extends from station O to station V of path P. 
         [0127]    In particular, station V is interposed between station T and station O, proceeding along the feeding direction of carrying units  20  along path P. 
         [0128]    Arc ν comprises, proceeding from station I to station V, arc α, station T and arcs β, γ, ∂. 
         [0129]    Arc μ comprises, proceeding from station V to station O, arcs ε, ψ. 
         [0130]    In the case shown, each positioning device  50  is interposed circumferentially to axis B between two subsequent relative carrying units  20  and is adapted to cooperate with portions of two subsequent respective sleeve labels  2  to lock them in respective desired positions ( FIGS. 3 and 4 ). 
         [0131]    In other terms, each positioning device  50  is associated to a pair of subsequent carrying units  20 . 
         [0132]    Positioning devices  50  are also angularly equally spaced about axis B. 
         [0133]    Positioning devices  50  also slide from and towards carrying units  20  along respective axes D orthogonal to axes C between retracted and forward positions. 
         [0134]    In particular, positioning devices  50  are arranged in respective forward positions along arc μ of segment R so as to cooperate and lock sleeve labels  2 . 
         [0135]    On the other hand, positioning devices  50  are arranged in relative retracted positions along arc ν of segment R so as to result radially spaced from drums  23  along respective axes D. 
         [0136]    In greater detail, carousel  7  comprises a plurality of supports  51  with respect to which positioning devices  50  are mobile between the retracted and forward positions. 
         [0137]    Each support  51  comprises in particular ( FIGS. 6 and 7 ): 
         [0138]    a body  53  fixed to a plate  55  ( FIG. 1 ) by means of two rods  54  parallel to axis B; and 
         [0139]    an element  56  mounted on body  53  and defining a dovetailed guide elongated in parallel to axis C and engaged by relative positioning device  50 . 
         [0140]    Each body  53  ( FIG. 7 ) comprises: 
         [0141]    a pair of sleeves  57 ; 
         [0142]    a pair of stems  58  sliding within sleeves  57  in parallel to respective axes D; and 
         [0143]    a pair of springs  59  interposed between respective stems  58  and respective sleeves  57 . 
         [0144]    Each stem  58  further comprises: 
         [0145]    an axial end  60  through which a screw connected to relative positioning device  50  passes, in the case shown by means of a threaded connection; 
         [0146]    an axial end  61  opposite to end  60 ; and 
         [0147]    a shoulder  62  interposed between ends  90 ,  91  along relative axis D. 
         [0148]    Sleeves  57  of each body  53  are also closed, on the opposite side of positioning devices  50 , by respective caps  63 . 
         [0149]    Caps  63  and ends  61  of stems  58  define respective chambers  65 , and comprise respective ducts  68  fluidically connected with chambers  64  and fluidically connectable selectively with a source of pressurised air. 
         [0150]    Springs  59  are interposed between shoulders  62  or respective stems  58  and the portions of respective sleeves  57  opposite to relative caps  63 . 
         [0151]    Springs  59  of each support  51  also preload stems  58  towards caps  63  and therefore maintain respective positioning device  50  in the respective retracted position along relative axis D with respect to drums  23 . 
         [0152]    Positioning devices  50  are displaceable in the respective forward positions along relative axes D with respect to drums  23 , feeding compressed air (in a manner not disclosed as it is not relevant for understanding the present description) within ducts  68 , along arc μ of segment R. 
         [0153]    Thereby, a pressure is generated within respective chambers  64 , which causes the displacement of respective stems  58  and thus of positioning devices  50  towards drums  23  and against the action of springs  59 . 
         [0154]    Each positioning device  50  comprises: 
         [0155]    a flat surface  70 , opposite to drums  23  of relative carrying units  20  and engaging the dovetailed guide defined by element  56 ; 
         [0156]    a surface  71  formed by two flat incident portions, opposite to surface  70  and facing relative sleeve drums  23 ; and 
         [0157]    a pair of curved surfaces  72  between which relative surface  71  is interposed. 
         [0158]    Surfaces  72  of each positioning device  50  are, in the case shown, configured as cylinder arcs and are interposed, along relative axis D, between surfaces  70 ,  71 . 
         [0159]    When sleeve drums  23  are in the lifted position, surfaces  72  of each positioning device  50  face and embrace respective portions of surfaces  25  of sleeve drums  23  and respective portions of sleeve labels  2  wound on above said surfaces  25 . 
         [0160]    Surfaces  72  of each positioning device  50  comprise a plurality of holes  73  selectively connectable to a plurality of vacuum sources  65  diagrammatically indicated in  FIG. 1 . 
         [0161]    More precisely, each positioning device  50  comprises ( FIG. 3 ): 
         [0162]    a channel  76  radial to axis B and parallel to axis D, passing through surface  62  and connectable to vacuum source  65 ; and 
         [0163]    a plurality of channels  77  each interposed between channel  76  and respective holes  73 . 
         [0164]    In the case shown, each positioning device  50  is formed by ( FIG. 4 ): 
         [0165]    a body  78  defining surfaces  70 ,  71 ,  72  and channels  76 ,  77 ; 
         [0166]    a pair of elements  79  defining respective holes  73 . 
         [0167]    In particular, elements  79  are made of an elastomeric material, in the case shown, silicone ( FIG. 4 ). 
         [0168]    In particular, machine  1  comprises a distributor  80  which is fixed with respect to axis B ( FIG. 1 ). 
         [0169]    Distributor  80  comprises in turn: 
         [0170]    a plurality of vacuum sources  65 ; 
         [0171]    an annular plate  82  having axis B and defining a plurality of through-slots  83  fluidically connected to vacuum sources  65 . 
         [0172]    Carousel  7  comprises an annular plate  88  having axis B, rotatable about axis B and resting on plate  82 . 
         [0173]    Carousel  88  also includes: 
         [0174]    a plurality of through-slots  86  (only some of which are shown in  FIG. 1 ) resting on plate  82  and fluidically connected with channels  76  and thus with holes  73  of positioning device  50 ; and 
         [0175]    a plurality of further slots  87  (only some of which are shown in  FIG. 1 ) resting on plate  82  and fluidically connected with holes  30  of sleeve drums  23 . 
         [0176]    Slots  86  are placed at slots  83  along arc μ of path P and are shifted with respect to slots  83  circumferentially to axis B along arc ν of path P. 
         [0177]    Therefore, holes  73  exert a suction action on respective sleeve label  2  along arc μ and exert no suction action along arc ν. 
         [0178]    Slots  87  are placed at slots  83  along arc μ of path P and are shifted with respect to slots  83  circumferentially to axis B along the remaining portion of path P, so that holes  30  exert a suction action on labels  10  along arc β of path P. 
         [0179]    Finally, labelling machine  1  can apply sleeve labels  2  having different formats and in different positions on relative containers  3 . 
         [0180]    For this purpose it is sufficient: 
         [0181]    to remove positioning devices  50  corresponding to the previous format of sleeve labels  2  from relative supports  51  and connect new positioning devices  50  corresponding to the new format of sleeve labels  2  on relative supports  51 ; and/or 
         [0182]    to vary distance H from surface  27  of upright  22 , to which drum  13  transfers sleeve labels  2  from respective carrying units  20 . 
         [0183]    The operation of labelling machine  1  is disclosed hereinafter with reference to a single container  3  and to a single carrying unit  20 , and from the time in which container  3  is provided in the lowered position by starwheel  11  to carousel  7  at station I. 
         [0184]    At station I, wall  5  of container  3  is rested on surface  24  of plate  29  and neck portion  4  of container  3  cooperates with free portions  36  of element  35 . 
         [0185]    Moreover, at station I, positioning device  50  is arranged in the retracted position along axis D and holes  73  of surfaces  72  are fluidically isolated from vacuum sources  65 , along whole arc ν of path P. 
         [0186]    More precisely, slots  86  are shifted with respect to slots  83  in a direction circumferential to axis B, along arc ν of path P. 
         [0187]    Thereby, channel  76  is fluidically isolated from vacuum sources  65  and holes  73  of positioning device  50  exert no suction action. 
         [0188]    Ducts  68  and thus chambers  64  are discharged and springs  59  elastically load stems  58  towards caps  63 , maintaining positioning device  50  in the retracted position along axis D. 
         [0189]    Container  3  is displaced from the lowered position to the lifted position along arc α of path P. 
         [0190]    Along arc α, the interaction between cam and cam follower  26  determines the displacement of sleeve drum  23  along axis C from the completely retracted position to the completely lifted position. 
         [0191]    At station T, drum  13  transfers flat labels  10  to surface  25  of sleeve drum  23  at distance H from surface  27  of upright  22 . 
         [0192]    Such a distance H determines the final application position of sleeve label  2  on container  3 . 
         [0193]    Sleeve drum  23  rotates about relative axis C along arc β of segment R, so that label  10  exiting from drum  13  winds completely on surface  25  and forms a cylinder with opposite edges  32  overlapped. 
         [0194]    Along arc β, the suction action of holes  30  maintains label  10  wound at distance H from surface  27  of upright  22 . 
         [0195]    At arc γ of segment R, welding device  40  welds edges  32  of label  10  and forms sleeve label  2 . 
         [0196]    Sleeve label  2  is also maintained at distance H from surface  27 , along arc β of path P. 
         [0197]    At this point ( FIG. 8 ), sleeve label  2  surrounds containers  3 , but is not yet fixed to container  3 . 
         [0198]    The further feeding of carousel  7  carries containers  3  with respective sleeve labels  2  along arc ∂ of segment R. 
         [0199]    At this point, display system  84  detects the angular position of each container  3  with respect to relative sleeve label  2  about axis C and controls, on the basis of the difference between this detected angular position and the desired angular position, a further rotation of sleeve drum  23  about axis C. 
         [0200]    This rotation of sleeve drum  23  does not cause the rotation of container  3 , as container  3  is retained between plate  29  and free portion  36  of element  35 . 
         [0201]    In other words, the friction due to the presence of container  3  prevents the rotation of plate  29  with sleeve drum  23 . 
         [0202]    At station V and up to station O, positioning device  50  is displaced from the retracted position to the forward position along axis D and vacuum sources  65  are fluidically connected with holes  73  of surface  72 . 
         [0203]    More precisely, when positioning device  50  is arranged in the forward position, surfaces  72  embrace respective portions of two sleeve labels  2  surrounding two subsequent containers  3 . 
         [0204]    In virtue of the suction action exerted by holes  73 , positioning device  50  locks the above said two sleeve labels  2  at distance H from surface  27  of respective uprights  22  along the whole arc μ of path P. 
         [0205]    More precisely, along arc μ, slots  86  are overlapped to slots  83 . 
         [0206]    Thereby, channel  76  is connected to vacuum sources  65  and holes  73  of positioning device  50  exert a suction action on sleeve labels  2  carried by two carrying units  20  associated to positioning device  50 . 
         [0207]    Ducts  68  are also connected to a compressed air source, so as to increase the pressure in chambers  64 . 
         [0208]    This pressure displaces, under the action of springs  59 , stems  58  along axis D and towards sleeve drums  23 , bringing positioning device  50  in the forward position. 
         [0209]    Along arc ε of the path, the interaction between cam and cam follower  26  determines the displacement of container  3  from the lifted position to the lowered position. 
         [0210]    In particular, while sleeve drum  23  is fed along arc ε, it is displaced along axis C from the lifted position to the totally lowered position. 
         [0211]    As may be seen in  FIG. 10 , this displacement determines a relative motion along axis C between container  3  and sleeve label  2  locked by the positioning device. 
         [0212]    This motion determines the final positioning of sleeve drum  2  with respect to container  3  in the desired position along axis C. 
         [0213]    Finally, while container  3  is fed along arc ψ, sleeve label  2  is heated by heating device  85 . This determines the thermal retraction of sleeve label  2  and the subsequent application—at least preliminary application—to container  3 . 
         [0214]    Hereinafter, container  3  with applied sleeve label  2  reaches station O of path P and is transferred to starwheel  12  and to conveyor  8 . 
         [0215]    From an analysis of the features of labelling machine  1  and of the relative method according to the present subject matter, the advantages it allows to obtain are apparent. 
         [0216]    In particular, in virtue of the presence of positioning devices  50 , machine  1  allows to position sleeve labels  2  in the respective desired positions along axes C with respect to containers  3 , simply by locking sleeve labels  2  while containers  3  are displaced from the respective lifted positions to the respective lowered positions. 
         [0217]    In particular, machine  1  requires no additional module for positioning sleeve labels  2  in the respective desired positions, thus resulting especially simple to manufacture and maintain with respect to the known solutions cited in the introduction of the present description. 
         [0218]    Furthermore, machine  1  allows, in virtue of display system  84  and of the actuator controlled thereby, to correct the angular position of sleeve labels  2  with respect to relative containers  3  and about relative axes C, after sleeve labels  2  have been formed along arc γ and before sleeve labels  2  are locked along arc μ. 
         [0219]    Thereby, machine  1  allows to apply sleeve labels  2  in respective desired angular positions on respective containers  3  with reference to respective axes C. 
         [0220]    There follows that machine  1  has functionalities which known solutions cited in the introduction of the present description do not have. 
         [0221]    Finally, machine  1  uses the same vacuum sources  65  both to create a suction action at holes  30  of sleeve drums  23  and at holes  73  of positioning devices  50 . 
         [0222]    Finally, it is apparent that modifications and variants not departing from the scope of protection of the claims may be made to machine  1  and to the method disclosed herein. 
         [0223]    In particular, sleeve label  2  could be arranged in the desired position by locking containers  3  and moving sleeve labels  2  with respect to containers  3 . 
         [0224]    Furthermore, sleeve labels  2  could vary the distances thereof from surfaces  27  of respective uprights  22 , while they are fed from station T to station V and reach distance H only at station V.