Patent Document

REFERENCE TO RELATED APPLICATIONS 
     This disclosure claims the benefit of the filing date of International Application No. PCT/EP00/03872, having an international filing date of Apr. 28, 2000, which designated the United States of America, and this disclosure is the United States national stage of that international application. This disclosure further claims priority to Germany patent application 199 19 880.2, filed Apr. 30, 1999, Germany patent application 199 20 905.7, filed May 6, 1999, and Germany patent application 100 02 401.7, filed Jan. 20, 2000. 
     FIELD OF THE INVENTION 
     The invention relates to a process and a device for the attachment of label jackets to products such as bottles. 
     BACKGROUND OF THE INVENTION 
     A corresponding machine is known from European Patent No. 0 584 516. This machine has a revolving table, with dishes that are arranged at regular intervals on a common sector of a circle, for the free standing uptake of bottles. On each one of these dishes, a roll of labeling hose, an installation for the separation of label jackets, and a pair of separating jaws that can be lowered and lifted for seizing the separated label jackets and to pull them over a bottle, are arranged in a manner so that they rotate. 
     The drawbacks of this construction design are the considerable cost and the fact that replacement of the numerous rolls of label hose is time consuming. Because of the free standing bottles, the speed of revolution and thus the production output are considerably limited. Furthermore, on the one hand, the evenness of the height of attachment of the label jackets to a multitude of bottles is unsatisfactory, and, on the other hand, the operating reliability is critical, especially when the external wall of the bottles are wetted with a fluid. These drawbacks are connected with the fact that a label jacket, at the time when the force of friction between the label and the bottle is greater than between the separating jaws and the label, stops the axial relative movement with respect to the bottle and adheres to it. The height of attachment of the individual jacket labels depends on the individual friction conditions and, therefore, it is not exactly defined. Moreover, the operating reliability is problematic when the separating jaws return to their original upper starting position, because there are still bottles on the support dishes. 
     SUMMARY OF THE INVENTION 
     The invention is based on the task of providing a process and a device with high fitting precision and operating reliability. 
     According to the invention, the bottles are seized, before a label jacket is pulled over them, in the area of their mantle surface, until the separating jaw pair which holds a label jacket, coming from above, surrounds, in a manner which is known in itself, at least for a portion of the longitudinal extent of the bottle to be fitted. In the subsequent course of the operation, the holding device for holding the bottles by their mantle surface is temporarily released, and the label jacket is pulled by the separating jaw pair, with simultaneous support of the bottom of the bottle, to the desired final position, where the lowering movement of the separation jacket pair is then stopped, while the label jacket continues to be held at its lower edge with friction lock by the separating jaws. Then the bottle is again seized by a part of its mantle surface which in the meantime has been covered with the label jacket that has been pulled over it, where the label jacket is held by friction lock or pressed against the external side of the bottle. The separating jaw pair releases the hold grip on the forward lower margin of the label jacket only then, and it is then lowered completely under the standing surface of the bottle. During this lowering movement of the separation jaw pair, the label jacket, advantageously, can no longer change its height position on the bottle, so that the position of the label jacket with respect to the bottom of the bottle is maintained uniformly with great precision in the case of a multitude of bottles, that is the height position tolerances of the height of adhesion can be kept in a very small range. 
     Advantageously, the separation jaw pair is designed in such a manner that its coupling action, with friction lock, is simultaneously applied to the radial internal and the external surface, and, as a result, it is possible to avoid an unnecessary large widening of a label jacket to generate sufficient frictional forces. 
     Since, in the proposed process, a bottle is supported at all times by its circumference, before, during and after the pull-over application of a label jacket, by an area of its mantle surface, high speeds of rotation can be achieved with an accordingly high production output without tipping of the bottle. 
     According to an embodiment variant of the invention, the separation jaw pair is lifted into the original upper position, only after the removal transport of the bottles that have been provided with a label jacket from a bottom dead center position, so that, advantageously, no disturbances can be caused by collision with a bottle or jamming of the separation jaws. 
     A particularly advantageous embodiment is one where the movements in height of the clamp jaw pair for pulling on the label jacket and for the return movement into the starting position is controlled by a cam control, but caused by a working cylinder or another appropriate drive (engine, etc.), because, as a result, the processing times, particularly the return time to the initial position, can be kept shorter than with a pure cam control, because there is no risk of self inhibition. The angle of rotation of the revolving table required for a complete cycle of movement of the clamp jaws is, accordingly, reduced, that is a smaller revolving table diameter is sufficient, with the same output level. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Below, a preferred embodiment of the invention is explained with reference to the figures. In the drawing: 
         FIG. 1   a  shows a machine with a revolving table for pull-over application of label jackets to bottles in a simplified diagrammatic top view, 
         FIG. 1   b  shows a radial cam assigned to the revolving table for the actuation of gripper clamps provided on the revolving table to hold bottles, as well as star wheels to load and unload the bottles in a top view, 
         FIGS. 2   a – 2   c  show a vertical cross section through the revolving table of  FIG. 1  seen in the direction of the arrow A, in different operating positions, 
         FIGS. 3   a – 3   c  show a diagrammatic top view of a separation jaw pair to seize and pull over label jackets in different operating positions, corresponding to the series of  FIGS. 2   a – 2   c,    
         FIG. 4  shows a vertical complete cross section through the revolving table of the machine in  FIG. 1 , 
         FIG. 5   a  shows a partial cross section of  FIG. 4  in an enlarged representation, 
         FIG. 5   b  shows a partial cross section corresponding to  FIG. 5   a  with an additional label jacket support, 
         FIG. 5   c  shows a top view of a label jacket support of  FIG. 5   b,    
         FIG. 6  shows a side view of a separating jaw unit in the viewing direction X in  FIG. 5   a,    
         FIG. 7  shows a top view of a separation jaw unit in the viewing direction Y in  FIG. 5   a,    
         FIG. 8  shows the development view of the radial cams for the movement in height of the separation jaw units, 
         FIG. 9  shows a top view of a bottle seizing unit at the revolving table of the machine according to  FIG. 1   b  in two different positions, and 
         FIG. 10  shows a variation of the machine according to  FIG. 1  with two revolving tables in a diagrammatic top view. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The machine  1  shown in  FIG. 1   a  essentially consists of a horizontal table top  2 , on which a revolving table  3  is rotatably secured with rotation about a vertical axis  3 ′, which revolving table is provided with several bottle dishes  4  arranged at regular intervals on a common sector of the circle. With displacement, a feed star wheel  5 , with associated feeding conveyor  7 , and a one-piece endless screw  8  and a delivery star wheel  6 , with associated removal conveyor  9 , are located on the revolving table  3 , with circumferential displacement. 
     Both the feed start wheel  5  and the delivery star wheel  6  are equipped at their periphery with seizing devices to seize and hold bottles at their mantle surface ( FIG. 1   b ). These gripping devices, for example, with swivel clamp arms which are in opposite direction in pairs, can be controlled at different places of their circumferential path, from a gripping position into a release position. Such clamp star wheels are described in detail, for example, in U.S. Pat. No. 5,607,045. 
     Above the common transfer point I between the revolving table  3  and the feed star wheel  5 , a cutting block  10  is provided on a cross bar  13 , where the cutting block is held in fixed position, for the feeding, unfolding of a film hose and for cutting off label jackets E, where the label film hose  11  is pulled off a hose reservoir  12  which is secured laterally to the machine, and, in the process, it is led to the cutting block  10  over several deflection rollers. The above mentioned cross bar  13  can be adjusted, in its height, for adaptation to different label jacket lengths, advantageously by an electromotor adjustment device, which is not shown in detail. The cutting block  10  can be constructed according to the Published German Patent Application DE 2950785 A1. 
     The revolving table  3 , the star wheels  5  and  6 , the conveyors  7  and  9 , as well as the one-piece endless screw  8  are driven continuously with synchronous speed and positioning with respect to each other, in a circular movement, by individual motor drives or a common machine drive and drive elements. The cutting block  10  has drive devices to effect, synchronously with respect to the movement of the revolving table, the advance, with exact positioning, of the label jacket hose and the cutting off of label jackets E by the cutting tool of the block  10 . Reference is made to the above mentioned German Patent Application concerning the exact construction. 
     The construction of the revolving table  3  is explained in greater detail below with reference to the vertical cross sectional representation shown in  FIGS. 4 and 5   a . The base of the revolving table  3  is formed by a horizontal support disk  30 , which is secured, so as not to allow rotation, at its center to a vertical main shaft  31 , and which bears, on its top side, the bottle dish  4  (not shown in the left half of  FIG. 4 ). Each bottle dish  4  is associated with a pair of parallel guide rods  32  in a vertical position on the top side of the carrier disk  30 , which pair is located radially inside the imaginary sector of a circle, on which the bottle dishes  4  are arranged. The ends of the guide rods  32  which are turned away from the carrier disk  30 , and turned upward, bear a ring disk  33 , whose middle is empty, and which is arranged parallel to the support disk  30 , on which ring disk several double-action pneumatic cylinders  34  are secured in a vertical upright position, in each case in the middle between a pair of guide rods  32 , with associated control valves  60 . To guarantee a stable hold of the cylinders  34 , the vertical upward housing ends of these cylinders are connected by a second ring disk  35 , which also has an empty middle. The piston rod  36  of the double-action pneumatic cylinders  34  can be moved out, vertically and in parallel, between a pair of guide rods  32  where, in the first ring disk  33 , a hole is present in each case in a position in the middle between the guide rods  32 , to allow the free penetration of the piston rods  36 . 
     The downward pointing end of the piston rod  36  is secured to slide block  37  which preferably has two parallel bore holes, each of which is penetrated by a guide rod  32 , which slide block, on its backside turned toward the main shaft  31 , presents an upper and lower guide roller  38  or  39 . The guide rollers  38  and  39  are, in each case, rotatably secured to swiveling levers  38   b  and  39   b  ( FIG. 6 ), which in turn are secured to slide blocks  37 . In the swiveling range of these levers, shock absorbers  38   c  and  39   c , respectively, with terminal abutments are attached to the slide block. 
     The top guide roller  38  is applied against the control surface of an upper, cylindrically bent, radial cam  40 , which is attached to the circumference of a horizontal disk  42 . This disk  42  has a pipe-like attachment, which is secured with pivot bearings to the top end of the main shaft  31 . At the bottom side of the disk  42 , there are several separator bolts  44 , which hang downward, and which are displaced at regular intervals over the circumference. At the lower ends of the separator bolts, a circular disk  43 , with empty middle, is attached, which carries at its circumference a bottom radial cam  41  for the other guide rollers  39 , with central attachment. In addition, the bottom radial cam  41  is held in a position so it cannot rotate by a clamp piece  45  provided on the separator bolts  44 . The bottom radial cam  41 , which is also cylindrically shaped, has a control surface pointed upward, on which the guide rollers  39  move. 
     The course of the curves of the two radial cams  40  and  41  can be seen in detail in the development view represented in  FIG. 8 , where the running direction of the guide rollers  38 ,  39  is directed, starting from the 0 degree mark (see also  FIG. 1   b ), in the direction of the arrow from the right to the left. In order to be able to use the machine  1  to process different bottle types and/or jacket labels E, where the adhesion height, that is the lower margin of the label jacket with reference to the bottom of the bottle, can be different, the lower radial cam  41  has a curve section  41   b  (see  FIG. 8 ) whose height can be adjusted continuously, and whose control surface determines the adhesion height of the label jacket E on the bottles F. This curve section  41   b  is connected in each case with two slide bushes  48  which are led in a manner so they can slide on two separated separator bolts  44  and which can be lifted or lowered, continuously, by means of a threaded spindle which is not shown ( FIG. 4 ). 
     In order to prevent the radial cams  40  and  41  from also turning, an angular torque support  46  is attached to the top side of the disk  42 , which support is braced by a stationary column  47  arranged; outside of the revolving table  3 , vertically on the table top  2 . 
     The bottom dishes  4  which are arranged on a common circle sector of the support disk  30  at a fixed height, and which in each case are surrounded by a centering ring  14  secured by a spring method, whose coaxial height can be moved, and which presents a margin which surrounds and holds the bottle dish  4 , and extends above it, and which is adapted to the contour of the bottom of the bottle. This centering ring  14  is coupled with a rod  15  which is led in a manner so it can be shifted in the support disk  30 , which projects with its lower end over the bottom side of the support disk  30  and supports a guide roller  17  ( FIG. 5   a ). Below the support disk  30 , at the circumferential path of the guide rollers  17 , a radial cam  18  is attached in a manner so it cannot be turned on the table top  2 , which, in the circumferential area from the delivery star wheel  6  to the feed star wheel  5  effects a lowering of the guide rollers  17  against the return force of a coil spring  16  with permanent vertical upward action. In this process, the upper margin of the centering ring  14  is held, during the feeding and delivery of the bottles F on the bottle dishes  4 , under the top side of the bottle dishes ( FIG. 2   c ). 
     In addition, each bottle dish  4  is associated with two shafts  19   a ,  19   b , which are arranged at an interval, parallel and vertically with respect to each other, with rotatable securing in the carrier disk  30 . Each of these shafts supports at its top end a horizontal grip arm  20   a  and  20   b , respectively, which extends outward and which is secured in a manner so it can not be turned, which arms together form controllable grip pincers  20  for seizing and holding a bottle F to be labeled on a bottle dish  4  ( FIG. 9 ). At the lower end of the shaft  19   a , a lever  21   a  fitted with a elongate hole  22  is attached, and at the lower end of the shaft  19   b , a lever  21   b  equipped with a vertical bearing bolt  23  is attached, in a manner so they can not turn. The bearing bolt carries a sliding block  24  which can be swiveled and which penetrates into the elongate hole  22 , and a guide roller  25  with displaced height, which roll is applied to the radial external control surface of a curve ring  26  which is maintained on the table top  2  in a manner so it can not turn. At the two levers  21   a ,  21   b , a tension spring  27  is applied, which is permanently active in the direction of a closing movement of the gripper clamp  20 . The form of the curve ring  26  which has two cam sections which project radially outward can be seen in  FIG. 1   b . When passing this section, the guide roller  25  is pressed outward, where the grip arms  20   a ,  20   b  swivel outward in opposite directions. The different positions of a gripper clamp  20  can be seen in  FIG. 9 . Holding of the bottle can occur at two places of its mantle surface with separation intervals in the axial direction, and alternately controlling the two axially displaced holding devices to rise, during the pull-over application of the label jacket, in such a manner that the object is at all times subject to or guided by at least one holding device. 
       FIG. 7  shows the construction of a spreading jaw unit  50  for the friction-positive seizing and pulling over of a label jacket E on the trunk of a bottle F, for example, a PET bottle. It consists of two internal jaws  51   a ,  51   b  and the counter arms  52   a ,  52   b  associated with them. The internal jaws each have a horizontal application surface  53  for the lower margin of a label jacket and a half-shell  54  which is bent upward, and whose curvature is adapted to the bottle diameter. The following half-shell, in the direction of rotation of the revolving table  3 , can have a lower height than the preceding half-shell. The counter arms, which are also curved, each carry two elastic rubber resilient pads  55  which can be applied radially from the outside to the half-shell, and which can be regulated to achieve a uniform seizing of a label jacket. On a support plate  56  which is inserted horizontally and can be quickly exchanged on the slide block  37 , two vertical bearing bolts  57  for the internal jaws and two additional vertical bearing bolts  58  for the counter arms are attached, where the bearing bolts  58  freely penetrate two curved elongate holes  59  in the internal jaws. In each case, a hinge  66  is used to couple the counter arms with their corresponding internal jaw, in such a manner that the swiveling of the internal jaws toward each other results in the swiveling of the counter arms away from each other, and vice versa. Close to the half-shells, one of these attracting tension springs  61  engages with the internal jaw. Approximately in the middle between the bearing bolts  58 , a control cam  68  which can not be turned is located on a shaft  62  is secured horizontally in the slide block  37 , where the height of the control cam is between the internal jaws. At the opposite end of the same shaft, a control segment  67  which presents a total of three guide rollers  63 ,  64 ,  65 , is secured in a manner so it can not turn. With the two guide rollers  63 ,  64  which are arranged on the side of the control segment turned away from the slide block, the symmetrically shaped control cam can, as desired, be adjusted by rotation in the clockwise direction or in the opposite direction by approximately 90° by means of curve section  70  arranged at the circumferential path, while the third guide roller  65 , located on the opposite side of the control segment, is used to maintain the label holding position of the spreading jaw unit  50 , while its downward movement is used for the pull-over application on a bottle. For this purpose, this guide roller  65  is associated with a vertical longitudinal guidance strip  71 , which rotates with the revolving table  3 , and where the guide roller runs along this guidance strip during the lowering. 
     In contrast to the above described embodiment, the counter arms, if appropriately shaped—as shown in  FIG. 1   b —can each be secured with one end rigidly to the diametrically opposite internal jaw. 
     The course of the operation during the passage of a bottle through the machine is described below, essentially with reference to  FIG. 1   a:    
     A bottle F which arrives on the conveyor  7  is seized by the one-piece endless screw  8 , introduced in an appropriate position into the feed star wheel  5 , seized by the latter&#39;s controlled clamps and positioned at the common contact point I on a bottle dish  4  of the revolving table  3 , where, at the same time, the centering ring  14  is led upward and the associated gripper clamp  20  is closed. The corresponding clamp of the feed star wheel instantaneously releases the bottle. 
     At the same time, a spreading jaw unit  50  which is associated with the bottle approaches the cutting block  10  as a result of its upward movement, where the half-shells  54  and the rubber resilient pad  55  are separated from each other at this time. At the same time, the label hose  11  is advanced from above downward, and a label jacket E is cut off, which is then located, with its lower margin, on the application surface  53  of the internal jaws  51   a ,  51   b , that is the half-shells are located within the label jacket and the rubber resilient pad outside. In order to prevent the tipping of the label jacket at the time of the uptake and acceleration in the direction of rotation of the revolving table  3 , a concave curved support shell  49  is located at the height of the label jacket E which has just been separated from the hose, which shell moves in the same direction as the revolving table—seen in the direction of rotation—and is applied to the back side of the label, where the support shell  49  is secured with fixed height at the radial external margin of the ring disk  33  by means of a bracket ( FIG. 5   b ).  FIG. 5   c  shows the shape of the support shell  49  in a top view. 
     Immediately thereafter, the shaft  62  with its control cam  68  is rotated in such a manner that the half-shells  54  are swiveled away from each other and at the same time the rubber resilient pads  55  are swiveled inward and in opposite directions, until the label jacket is clamped at its lower margin, outside and inside, with friction lock. In the case of a stretchable jacket, the latter is expanded in the process to an extent which is larger than the diameter of the bottle. 
     When passing through sector II ( FIG. 1   a ), the label jacket is pulled, by the separation jaw unit  50  which is pressed downward by the pneumatic cylinder  34 , from top to bottom over a bottle F. As soon as the spreading jaw unit, during the lowering movement, approaches the gripper clamp  20  which holds the bottle, the gripper clamp is opened for a short time, long enough so that the spreading jaws are able to pass through the gripper clamp (second half in sector II). Later, the gripper clamp  20  can again be closed, to such an extent that the bottle is led by its circumference, but a sufficient slit remains to continue pulling through the label jacket. As soon as the label jacket has reached the intended adhesion height, the lifting movement of the spreading jaws is stopped, the gripper clamp  20  is completely closed (label pressed against the bottle trunk) and the half-shells  54  are swiveled slightly inward (the clamping of the lower label margin is released). These processes occur in sector III. 
     Even before the delivery star wheel  6  is reached, the spreading jaw unit  50  is now again lowered, until the half-shells are located completely under the bottle dishes  4  ( FIG. 2   c ). In the case of a shrink wrap jacket, “which has an internal diameter equal to or larger than the external diameter of the bottle,” the preliminary shrinking (hot air, etc.) for affixing the label can now occur at the revolving table  3 . In addition, the centering ring  14  is lowered now, and the gripper clamp  20  is opened, when the delivery star wheel  6  has seized the bottle for transfer to the conveyor  9 . 
     Then, the pneumatic cylinder  34  is adjusted for lifting, so that the spreading jaw unit  50  again reaches its original upper position before passing the feed star wheel  5  (sector IV). 
     During the entire treatment process, the bottles are transported without change in height position through the machine. 
       FIG. 10  represents a machine variant for high outputs, which is formed by a mirrored arrangement of two individual machines according to  FIG. 1   a  or  1   b , that is this double machine has two feed star wheels  5  and  5 ′, two carousels or revolving tables  3  and  3 ′, as well as two delivery star wheels  6  and  6 ′, but only one common conveyor  7 , one removing conveyor  9  and the one-piece endless screw  8 . The star wheels  5 ,  5 ′ or  6 ,  6 ′, respectively, which are opposite each other and which can be driven in opposite directions to each other, in each case contact the sector of a circle of their counter part and they are equipped, at the circumference, with controllable clamps—according to the representation in  FIG. 1   b —which can be adjusted selectively from a seize position for seizing a bottle into a release position, and vice versa, by means of switch cams, not shown, which are arranged in a fixed position at certain places of their circumferential path. This partition measure, that is the interval between two adjacent bottle dishes  4  on the two revolving tables  3  and  3 ′, is twice that of the partition measure of the feed and delivery star wheels  5 ,  5 ′ and  6 ,  6 ′. All the bottles which are supplied continuously in a single track by the feed conveyor  7  are pulled apart by the one-piece endless screw  8  to the partition measure of the feed star wheel  5  and seized by the latter. At the common contact point of the two feed star wheels  5  and  5 ′ each second bottle F is released by the first feed star wheel  5  and simultaneously seized by the second feed star wheel  5 ′. In this manner, the bottles F and F′ are alternately led to the two revolving tables  3  and  3 ′. Each revolving table is associated in the transfer area of its feed star wheel with a cutting block  10  or  10 ′ for the separation of label jackets E from a label film hose. On the side of the delivery, the finished, labeled, bottles F and F′, which arrive alternately from the two revolving tables  3  and  3 ′ at the common contact point of the two delivery star wheels  6  and  6 ′, are again combined to one row and they are transferred from the delivery star wheel  6 ′ to the removal conveyor  9 . As a result of this modular construction, a larger range of outputs can be covered than with only two variants. It is understood that, instead of clamp star wheels, it is also possible to use alternate solutions with differently designed holding devices for the selective seizing of the bottles, such as, for example, vacuum star wheels or similar transport installations.

Technology Category: y