Transverse lane labeling method and labeller

A method for applying labels on articles, which are guided in parallel lanes, for which in each case a row of labels is dispensed by a label dispenser from a backing, taken up by a transfer path guided transversely over the lanes and transferred in a transfer step onto the articles, the transfers step comprising the moving of a lifting tool, extending along a section of the transfer path onto article lanes for pressing the labels onto the articles and the return of the lifting tool into its starting position. The dispensed labels are taken up at a point of the transfer path, which is at a distance from the lifting tool, and the dispending of a row of labels is commenced before the step of transferring a previous row of labels is concluded.

BACKGROUND OF THE INVENTION

The present invention relates to a method for the multi-lane and multi-row application of labels on articles, such as packaging or the like, which are guided in parallel lanes.

Transverse lane labeling systems are known, for which the articles such as thermoformed packaging or the like, guided in parallel lanes, are labeled with the help of a transfer device, which extends transversely over the article lanes. For this purpose, the labels are, first of all, dispensed on a transfer path, such as an endless transporting belt and transferred to a transferring device. This comprises a lifting tool, which extends along a section of the length of the transfer path and can be lowered onto the articles. At the same time, a row of labels on the transfer path is taken hold of and pressed against the articles. After the labels are pressed on, the lifting tool can return once again back into its starting position. This cyclic movement of the lifting tool against the articles and back again is also referred to in the following as the transfer step.

The German Offenlegungsschrift DE 102 28 243 A1 of the Applicant shows, for example, a traverse lane labeler, the transfer device of which comprises a suction box, over which the transfer path runs, so that the non-adhesive side of the labels can be held by suction at the underside of the suction box. In this case, the lifting tool is formed by a sliding plate arrangement, which can be moved out of the suction box and presses the labels, held by suction, against the articles. The speed of the transfer path and of the backing film, from which the labels are dispensed, can be matched to one another in such a manner, that the labels, taken up on the transfer path, are at the desired distances from one another, which correspond to the lateral distances between the article lanes.

If the articles are to be labeled on the underside, the transfer path and the transfer device must also be disposed underneath the article lane. With that, parts of the labeler requiring maintenance are in an area of the machine frame, to which access is difficult, so that the operation becomes more difficult. In particular, a new backing film of the label dispenser must be threaded into the dispenser edge at regular intervals. If too much time is required for this procedure, the downtime of the labeler is too high and leads to a loss in output. For conventional labelers, shifting the parts, which require service, to an area of the machine, which is more accessible, depends on the construction and is not readily possible.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a labeling method of the type named above, by means of which the operation and maintenance of the above-described labelers is facilitated without suffering a loss of performance. It is a further object to create an appropriate labeler, which is suitable for carrying out such a method.

For the inventive method, the dispensed labels are taken up at a point of the transfer path, which is at a distance from the lifting tool. For this purpose, the transfer path has a free section, which cannot be taken hold of by the lifting tool and which extends upstream from the lifting tool with respect to the running direction of the lane. The labels are transported from the dispensing edge to the lifting tool on this free section. The dispensing edge of the label dispenser may therefore be disposed remote from the lifting tool, for example, in a part; which is outside of the machine frame and is readily accessible. Threading the backing film around the dispensing edge is made easier thereby.

So that there is no loss of performance during the operation of the labeler due to the additional transporting path between the dispensing edge and the lifting tool, the dispensing of the leading label of a row of labels commences already during the transfer step, that is, even before the lifting tool, after it has pressed a preceding row of labels against the articles, has returned back to its starting position. Accordingly, the time, which the lifting tool requires for its movement, can be utilized for transporting subsequent labels to the lifting tool. Ideally, then, no additional time is used in the labeling cycle for the transporting path. The time, at which the dispensing of a row of labels is commenced, is determined here as a function of the transporting path of the labels from the point, at which they are taken up on the transfer path, until they reach the lifting tool, of the lane speed of the transfer path and of the lifting speed of the lifting tool.

Accordingly, the inventive method provides the possibility of shifting the dispensing edge to an easily accessible point of the labeler without lengthening the time required for the application of a row of labels. The additional transporting path is compensated for by selecting the dispensing time early as a function of the speed or of the actual position of the lifting tool. It is even possible to commence the dispensing of a new row while the lifting device with a prior row of labels is still on the way in the direction of the articles. If the lifting time of the lifting tool changes due to a rise in temperature, a changed contacting pressure or the like, the dispensing time can be adapted correspondingly.

In a preferred embodiment of this method, the time of commencing the dispensing of a row of labels is optimized in such a manner, that the period that elapses from the time that the lifting tool returns to its starting position until the leading label of the row of labels reaches the lifting tool, is minimized.

In this case, the new row of labels reaches the lifting tool at the very time when the latter is available for a new transfer step. The time, required for moving the lifting tool, accordingly is used optimally for transporting the labels from the dispensing edge to the lifting tool.

In a further preferred embodiment of the method, the rate of movement of the lifting tool is measured and the time of commencing the dispensing of a row of labels is set as a function of a prior measurement of the speed, with which the lifting tool is moving.

This method takes into account any change in the speed of the lifting tool. In this case, the time, at which the labels are dispensed, is adapted dynamically to the operation of the labeler.

Preferably, the backing film and the transfer path are driven continuously and their driven speeds behave like the center-to center distances between the labels on the backing film and the average lateral center-to center distances between the article lanes.

A labeler for carrying out the inventive method is claimed by claim5. The dependent claims6to11relate to preferred embodiments of such a labeler.

DETAILED DESCRIPTION

The labeler10, shown inFIG. 1, comprises a machine frame12, which rests on legs14and in which articles16, such as thermoformed packages or the like are transported in parallel lanes18in a longitudinal direction A of the machine frame12. InFIG. 1, four lanes18of articles16can be identified, which hang together by way of a packing film20for closing off the packages, so that the articles16form a composite. A second packaging film can be applied by a unit22, which may comprise packaging film dispensing rolls24, guide rollers and the like and further parts for unwinding the film and welding the latter to the articles16. Such units22are known and are therefore not described in greater detail here. Furthermore, a conventional labeling unit25, such as the one known, for example, from the DE 102 28 243 A1, is mounted above the article lanes18.

The machine frame12comprises two parallel, horizontal longitudinal carriers26,28, between which the article lanes18run. Lateral lining plates30, the upper edges of which are mounted to the machine frame12and which extend downward as far as the vicinity of the ground, are mounted at the respective longitudinal carriers26,28.

Downstream from the unit22for applying the packaging film20, a further labeling unit32is disposed, which applies the labels, the details of which are not shown inFIG. 1, to the underside of the articles16. For this purpose, the labeling unit32comprises a label dispenser34, which is disposed to the side of the article lanes18. The label dispenser34comprises, in the usual manner, a supply roll36, from which a backing film37is passed over a number of guide rollers, and a dispensing edge40to a reel42, onto which the empty backing film37is rolled. This principle of functioning is also already known. For the construction existing here, the supply roll36, the reel42as well as some of the guide rollers38are mounted at a head44, which is above the article lanes18and carried by a vertical arm46, which is in front of the lining plates30laterally outside of the machine frame12. At its lower end, the arm46is held with the help of a slide block48on a horizontal guide rail50, which is formed by a bar with a round cross section. This bar50extends parallel to the longitudinal carriers26,28underneath the lanes and is held at its ends between two flanges52, which, in turn, are connected by struts54, protruding vertically at the flanges52, with one of the longitudinal carriers28. Secure fastening of the bar50at the two fastening points of the longitudinal carrier28is ensured in this way and the arm46, which carries the head44of the label dispenser34, can be shifted along the bar50.

At its lower region above the slide block48, the arm46of the label dispenser34carries two further guide rolls56,58as well as the dispensing edge40. The backing film37accordingly is guided from the supply roll36over the guide rolls38at the head44downward along the arm46over the guide roll58, over the dispensing edge40and, from there, upward around guide roll56in the direction of the head44, in order to be wound on the reel42. Accordingly, the dispensing edge40is disposed somewhat below the lateral longitudinal carrier28in a region of the machine frame12, which is easily accessible from the outside. In particular, for threading the backing film37over the guide rolls56,58onto the dispensing edge40, it is not necessary to grasp far into the lower region of the machine frame12underneath the article lanes18, so that the operation of the labeling dispenser34is facilitated. A cut-out62in the lateral lining plates30ensures good accessibility to the parts of the labeling unit32, which are disposed laterally below the article lanes18. These furthermore comprise a transporting lane64for accommodating the dispensed labels as well as a transfer device66, which transfers the labels from the transfer path lane64to the underside of the articles16. This is to be described in greater detail below. Within the scope of the present invention, the dispensing edge40may even be shifted into a region laterally on the outside of the machine frame12, so that the dispensed labels are transported through the cut-out62to the transfer device66underneath the article lanes18.

As can be seen in greater detail inFIGS. 2 and 3, the transfer device66comprises a suction box68, in which a reduced pressure is produced. The transfer path64, which is formed by two mutually adjoining endless belts70,72, passes over the upper side of the suction box68. Each of these endless belts70,72is formed by two parallel strip-shaped belts. Air can be aspirated into the suction box68through the spaces between these endless belts70,72, so that labels, which are taken up by the transfer path64, can be held by suction at the transfer path64. These labels then lie on the respective top strand of the endless belts70or72.

The endless conveyor belt70on the left inFIG. 2runs over a left free-running roll74as well as over a right driven roll76, over which also the right endless conveyor belt72is passed with its belt, so that both endless conveyor belts70,72can be rotated by the joint drive shaft76. The right endless conveyor belt72finally also runs over a further roll78at the right end of the suction box68. Whereas the left endless conveyor belt70extends horizontally in the transverse direction under the article lanes18, the other endless conveyor belt72runs slightly downward with respect to the horizontal.

Deviating from the embodiment introduced here, it is possible to form the transfer path64by a single endless conveyor belt.

The transfer device66furthermore comprises a lifting tool for transferring labels, which are held by suction at the transfer path64, onto the articles16. This lifting tool is formed by a set of slide plates80, which inFIG. 2are recessed completely into the suction box68and are shown in their fully extended position inFIG. 3. In their initial position inFIG. 2, the parallel, horizontal upper edges82(FIG. 3) lie directly beneath the upper surface of the transfer path64, so that the labels can be transported without hindrance on the transfer path64over the slide plates80.

After the labels have been positioned by the transfer path64over the slide plates80, the latter can be raised through the interstices between the belts of the conveyor belt70, so that they can take hold of the labels. In the completely extended position inFIG. 3, the labels are pressed against the underside of the articles16. The upper edges82of the slide plates80are dimensioned, so that they extend approximately over the whole length of the conveyor belt70extending parallel under the article lanes18. Accordingly, during the lifting motion of the slide plate set80, labels on the slightly inclined transfer path72are not taken hold of by the upper edges82.

It can furthermore be seen clearly inFIGS. 2 and 3as well as in the enlargement inFIG. 4that the dispensing edge40is disposed remote from the slide plates80at the right end of the transfer path64, which end is formed by the right end of the slightly inclined conveyor belt72. The labels, dispensed from the backing film, accordingly are taken up at the right end of the transfer path64, conveyed on the transfer path72in the direction of the first conveyor belt70, onto which they are transferred until a row of labels is available on the section of the transfer path64, which is disposed above the slide plates80, for transfer to the articles16. The transfer is accomplished by raising the slide plates80, the upper edges82of the plates80taking hold of the labels. After the labels are pressed against the articles16, the slide plates80are returned to their starting position inFIG. 2. During such a transfer step, which includes the upwards and downwards movement of the slide plates80, further labels can already be taken up at the upstream end of the transfer path64and transported to the slide plates over the free section of the transfer path64, which cannot be taken hold of by the slide plates80. This process can be controlled in such a manner, that the subsequent labels reach the section of the transfer path64, which can be taken hold of by the slide plates80, when the slide plates80are once again in the retracted position inFIG. 2. In this way, it is avoided that additional time is employed for transporting the labels from the dispensing edge40to the slide plates80, since the dispensing of a subsequent roll of labels already takes place during the transfer of a preceding row of labels to the articles16.

This process is to be explained in greater detail by means of the diagrammaticFIGS. 5 to 7.

FIGS. 5 to 7show the suction box68in a diagrammatic side view. The transfer path64, the transporting direction of which is indicated by an arrow B pointing to the left, extends at the upper side of the suction box68. Within the suction box68, the set of slide plates80are shown movable upward and downward and in different lifting positions in the Figures. The completely extended upper position of the slide plates80is shown inFIG. 5. On the other hand,FIG. 7represents the retracted starting position of the plates80ofFIG. 2, in which the upper edges82of the slide plates80are located immediately below the upper side of the transfer path64or terminate with this surface. It is important that, in this position, the labels84,86,88,90, conveyed on the transfer path64, can be conveyed without interference over the set of slide plates80, without being impeded by the slide plates80.

As already mentioned, the transfer of a row of labels from the transfer path64to the article16takes place in a transfers step, in which the set of slide plates80, as a lifting tool, is extended from its starting position inFIG. 7against the articles16for pressing the labels against these and subsequently returns once again to its starting position.FIG. 5shows the set of slide plates80in its fully extended contacting position, that is, still before the conclusion of the transfers step. At this time, the dispensing of a subsequent row of labels from the backing film37to the free right end of the transfer path64can already be commenced. InFIG. 5, four labels84,86,88,90of a row of labels are pressed by the set of slide plates80against the articles16. At the same time, at the dispensing edge40, the first label92of a subsequent row of labels, which is to be transferred, is dispensed onto the free end of the transfer path64, which cannot be taken hold of by the set of slide plates80. During the dispensing, the transfer path64, driven by the two conveyor belts70,72, moves in its running direction B and transports the dispensed label92in the direction of the slide plates80. At the same time, the movement of the transfer path64and of the backing film37can be controlled in a suitable manner so that a desired distance between labels on the transfer path64is achieved. For example, the backing film37and the transfer path64can be driven continuously, their driving speeds being in the same proportion as the distances between the centers of the labels on the backing film37and the center-to-center spacing of the article lanes18, as described in the German patent 102 28 243 of the Applicant. Alternatively, the transfer path64can also be driven intermittently and, for the dispensing process, in each case moved forward and held in the next taking-up position.

During a subsequent return movement of the slide plates80in the direction of the starting position, that is, in the downward direction, the dispensed label92was transported already in the direction of the slide plates80and a subsequent label94is placed on the transfer path64. The time, at which the dispensing of a new row of labels is commenced, can be selected as a function of the transporting path of the labels from the point, at which they have taken up on the transfer path64, until they reach the slide plates80, as a function of the speed of the transfer path64and as a function of the speed of movement of the slide plates80. The transport path of the labels is determined here by the distance between the dispensing edge40and the right edge96of the slide plates80, which is the first edge to be reached in the running direction B of the transfer path64. InFIG. 7, the front edge of the next row of labels92,94,98has just arrived at the section of the transfer path64, which can be taken hold of by the upper edges82of the slide plates80. By further conveying on the transfer path64, the subsequent labels92,94,98accordingly are positioned over the slide plates80and can be pressed by the upward motion of the slide plates80against the articles16, as shown inFIG. 5.

This procedure accordingly can be summarized as follows. While a first row of labels84,86,88,90is being conveyed in a section T2of the transfer path64, over the length of which the upper edges82of the slide plates80extend, this row of labels84,86,88,90is transferred in a transfer step to the articles16, in that the slide plates80are moved against the articles16. This transfer step furthermore comprises the return motion of the slide plates80into their starting position inFIG. 7. During this return motion or already during the upwards motion of the slide plates80, the dispensing of a subsequent row of labels92,94,98onto the free section T1of the transfer path64commences, the transfer path64extending, with respect to the running direction B of the transfer path64, downstream of the slide plates80. In this free transfer path section T1, the labels can be conveyed without interference in the direction of the slide plates80even during the upward and downward motions of the slide plates80. The starting time of the dispensing of the subsequent row of labels92,94,98can be optimized so as to minimize the interval between the time that the slide plates80return to their starting position (FIG. 6) and the leading label92of the new row of labels92,94,98reaches the lane section T2, traversed by the slide plates80. In other words, the new row of labels92,94,98is conveyed over the slide plates80at the very moment, in which the slide plates80have just once again reached their starting position. In this way, no time is lost during the conveying of the labels from the dispensing edge40to the slide plates80; instead, at least a portion of the time, required for the transfers step, is utilized for the conveying.

It is therefore possible to increase the distance between the dispensing edge40and the slide plates80without lengthening the labeling time and without the loss of performance associated with such a lengthening. Accordingly, the dispensing edge40can be shifted to a point of the labeler, which is easily reached by the operating personnel. This point does not have to be directly on the slide plates80and, instead, may be disposed at a distance from the latter. The shifting of the dispensing edge40to a point at a distance from the lifting tool therefore becomes effectively possible only by the inventive control of the dispensing process.

Since the operating conditions of the labeler may change, the lifting speed of the lifting tool advantageously is measured and the starting time of the ammencement of the dispensing of a new row of labels92,94,98can be adjusted as a function of the preceding lifting speed measurement of the slide plates80. Accordingly, the time of dispensing the labels on the free section T1of the transfer path64is selected optimally also during the operation of the labeler. For this purpose, the inventive labeler comprises a suitable control device as well as measurement devices, which measure, aside from the speed of movement of the slide plates80, also the speed of the transfer path64. Optionally, the basic position of the slide plates80can also be determined.