This invention relates to a web of adhesive labels for application to articles arranged in rows.  In an important specific aspect, to which detailed reference will be made herein for purposes of illustration, the invention is particularly concerned with the application of tax stamps to cigarette packages contained in cartons. 
Many U.S. states require that state tax stamps be applied to all cigarette packages sold within their borders.  In present-day commercial practice, cigarette packages as supplied by manufacturers to distributors lack tax stamps and are enclosed in cartons each typically holding ten packages arranged in two parallel rows.  The distributors must accordingly open every carton and apply tax stamps to all the contained packages. 
Various types of more or less automated equipment have heretofore been proposed and used for performing this operation.  Commonly, in such apparatus, successive cartons are fed lengthwise past a plow which opens their side flaps to expose the ends of the cigarette packages, then advanced to a station at which tax stamps are applied to the exposed package ends, and finally transported past devices for gluing and reclosing the carton flaps.  The stamps may be inked impressions directly imprinted on the package ends, or transfer labels (decalcomanias), e.g. supplied in sheets.  Use of paper labels affords potential benefits, however, especially from the standpoint of security, because paper labels can bear a complex intaglio imprint which is difficult to counterfeit. 
Heretofore, the application of tax stamps in the form of labels to cigarette packages (i.e. using known types of equipment) has been attended with various disadvantages.  In particular, it has generally been necessary to bring each carton to a full halt while the labels are applied, with the result that the rate of production (number of cartons stamped per unit time) has been undesirably slow and inefficient.  The label-handling portions of the equipment have often been inconveniently complex in structure and operation.  It has frequently been difficult or impossible to adjust the apparatus for use with cigarette packages of different heights.  In addition, the known machines have sometimes been susciptible to jamming or other malfunctions causing misapplication or nonapplication of stamps or damage to the cigarette cartons. 
The copending U.S. patent application of John J. Kimball, Harry V. Kirk, Richard L. Roule, Richard C. Sennett, and Peter J. Sorbo (said Kimball, said Roule, and said Sorbo being the applicants herein), Ser.  No.  587,375, filed concurrently herewith, for "Apparatus and Procedure for Applying Adhesive Labels to Articles," describes and claims apparatus for applying adhesive labels to upwardly facing surfaces of each of a multiplicity of articles arranged contiguously, with their upwardly facing surfaces substantially coplanar, in a plurality of parallel rows each including a plurality of the articles.  This apparatus broadly includes the combination of means for defining a rectilinear path for concurrent lengthwise advance of the rows of articles past a predetermined locality; means for providing, at a second locality spaced from the defined path, a multiplicity of separate adhesive labels arranged, in the same number of rows as the articles, for register respectively with the upwardly facing surfaces of articles advancing in the aforementioned defined path; and means for transporting the labels (lengthwise of the rows of labels) from the second locality into contact with the upwardly facing surfaces of the advancing articles at the aforementioned predetermined locality, in such manner that the labels and the articles are moving in the same direction and at the same speed as they come into contact, while maintaining the above-described arrangement of the labels during such transport.  It will be understood that the term "multiplicity" herein means at least four; that the term "plurality" means at least two; and that references to directions such as "upwardly" are employed in a relative rather than an absolute sense, i.e. to indicate relative orientations or positions of localities or apparatus elements. 
As a particular feature of this apparatus, the label-providing means is designed for use with labels supplied as an elongated web of flexible sheet material having one surface bearing an adhesive material and an opposite surface bearing a plurality of spaced-apart rows of label imprints extending longitudinally of the web, wherein the spacing between adjacent rows of imprints is equal to a predetermined desired spacing between applied labels on adjacent rows of articles advancing past the aforementioned predetermined locality, and the number of rows of imprints is equal to the number of such rows of articles.  This label-delivering means includes means for advancing the web lengthwise along a path leading toward the second locality; means, positioned in the last-mentioned path, for slicing out and removing from the advancing web a longitudinal strip portion between each two adjacent rows of imprints; and means, positioned in the last-mentioned path beyond the slicing means, for cutting the advancing web transversely to separate the rows of imprints into individual labels, and for delivering the individual labels to the second locality in the above-described arrangement.  The term "label imprint" refers to an imprinted portion of the web which, after separation from the web by the slicing and cutting means, becomes a single label, to be applied to one article; in situations where two or more label imprints as thus defined are initially undifferentiated portions of a continuous imprint (e.g. extending, transversely of the web, across a web portion which is to be sliced out), it will be understood that reference herein to spaced-apart rows of label imprints designates the disposition and arrangement on the web of those undifferentiated portions which ultimately become separate single labels. 
As further set forth in the aforementioned copending application, the label-transporting means (which constitute the means for applying the labels to the articles) may comprise a cyclically movable endless surface disposed and dimensioned for simultaneous tangential engagement with the upwardly facing surfaces of adjacent articles in all the rows of articles at the aforementioned predetermined locality as the rows of articles advance together in the defined rectilinear path, the endless surface being mounted above that path for movement in the same direction as the rows of articles at the aforementioned predetermined locality; and means for releasably holding individual labels on the endless surface at plural spaced rows of plural spaced sites positioned for register with the upwardly facing surfaces of the articles as the endless surface moves and the rows of articles advance in the defined path.  Drive means are provided for unidirectionally advancing the rows of articles in the defined path, and moving the endless surface, at the same speed. 
Thus, the transporting means may include a drum, mounted above the defined path of article advance for rotation in a plane containing that path (i.e. in the vertical plane that contains the horizontal rectilinear center line of the defined path of article advance), and having a cylindrical periphery (constituting the endless surface) having suction openings at the aforementioned spaced sites, together with means for applying suction through the openings to hold the labels against the drum periphery at those sites. 
The label cutting and delivering means mentioned above may include a web-cutting element positioned at a third locality spaced from the second locality, and a second drum having a periphery formed with spaced rows of spaced suction openings for picking up the cut labels at the third locality and transporting them into contact with the periphery of the first-mentioned drum at the second locality for transfer thereto, means being provided for applying suction through the second-drum openings to hold the labels on the periphery of the second drum during such transport.  The second drum is arranged for rotation in the same plane as the first drum; advantageously this plane also contains the center line of the path of advance of the web to the slicing means and the web-cutting elements.  The orientation of the web in the last-mentioned path, and the arrangement of the first and second drums, are such that the labels are transported on the first drum with their adhesive-bearing surfaces facing outwardly, i.e. in position for contact with and adhesion to the upwardly facing surfaces of the advancing articles at the predetermined locality of label application in the defined path of article advance.  Conveniently, the adhesive employed for the labels is heat-activated, and means are provided for supplying heat to activate the adhesive only as the labels are being carried on the first drum, so that the web and labels do not tend to stick to the second drum or to the web-handling elements at and ahead of the web-cutting element. 
As will be appreciated from the foregoing description, the apparatus of the aforementioned copending application applies labels to the rows of articles while the articles are advancing past the predetermined locality at a constant speed, owing to the fact that when the labels arrive at that locality they are moving in the same direction and at the same speed as the articles and are already arranged in properly spaced positions for register with the upwardly facing surfaces of the articles; hence the rate of production is advantageously rapid as compared with known label-applying systems that require the articles to be stationary while labels are applied.  The initial provision of the labels as spaced rows of imprints on an elongated web establishes the transverse spacing of the labels, and this transverse spacing is maintained throughout the web- and label-handling portions of the apparatus by virtue of the alignment of the paths of web and article advance with the common plane of rotation of the first and second drums, so that there is no need to displace the labels transversely (as and after they are separated) in order to position them properly for application.  The spacing between successive suction openings in each row of openings on the drums corresponds to the requisite spacing between the label-receiving surfaces of successive articles in each row of advancing articles; the rate of web advance and cutting element operation are synchronized with the rate of rotation of the drums so that successive cut labels are picked up by successive suction openings of the second-drum periphery, thereby to provide proper longitudinal spacing between labels. 
In a specific sense, the apparatus of the aforementioned copending application (including the above-described features) is arranged for applying labels to coplanar upwardly facing end surfaces of identically shaped, dimensioned and oriented articles arranged in groups each consisting of the same predetermined plurality of contiguous rows each containing the same predetermined plurality of contiguous articles aligned with the articles in each adjacent row, such groups being exemplified by conventional cigarette cartons each containing ten cigarette packages arranged in two rows of five packages each.  The groups of articles are advanced in succession, lengthwise of the rows, along the aforementioned defined path.  Means are provided for intermittently actuating the web-advancing means and the web-cutting means, in response to the advance of each group of articles along the defined path toward the predetermined locality, to deliver to the second drum a plurality of separated labels equal in number to the articles of a group.  The apparatus may also include means, disposed in the defined path of article advance ahead of the predetermined locality, for opening the flaps of cigarette cartons to expose the package ends for application of labels, and means for reclosing the carton flaps beyond the predetermined locality.  In addition, the apparatus may include means for interrupting operation in response to the sensed occurrence of any of the following conditions: jamming of a carton, presence of a carton flap occluding the package ends beyond the flap-opening means, absence of a label web in the path of web advance, or failure of the heating means to maintain an adequately high temperature for activation of the label adhesive. 
The label-providing and label-transporting means may be carried on a head disposed above the aforementioned predetermined locality, and means may be provided for adjusting the vertical position of the head relative to the path of article advance, thereby to accommodate articles (e.g. cigarette packages) of different heights.  The carton-flap-opening and closing means may also be carried on this head, for vertical movement therewith. 
In another aspect, the invention described and claimed in the aforementioned copending application contemplates the provision of procedure for applying labels to articles, such procedure being exemplified by the operation of the apparatus and system described above.