Shrink-film hole-burning device
United States Patent [1 1 Davis et a1.  
 [ 1 Apr. 8, 1975 1 1 SHRINK-FILM HOLE-BURNING DEVICE [73] Assignee: The R. T. French Company.  
 Rochester, NY.  
 [22] Filed: Feb. 9, 1973 [21] Appl. No.: 331,288  
  [52] US. Cl. 219/243; 30/140; 83/171; 156/513; 156/515; 156/581; 219/221; 219/229 [51] Int. Cl. H051) 1/00; B26d 7/10 [58] Field of Search 219/221, 227, 229. 243; 156/515. 581, 251, 513; 83/15, 16, 170, 171; 30/140 [56] References Cited UNITED STATES PATENTS 2122.368 6/1938 Englcr 219/221 UX 2,615,111 10/1952 Paquette et a1. 83/170 3075573 1/1963 Piazzc 83/171 X 3.187.381) 6/1965 Harrison 83/171 X 3.461567 8/1969 Villers et al. 219/229 X 3.503.097 3/1970 Krupp 219/229 UX FORElGN PATENTS OR APPLICATIONS 1.479.878 9/1969 Germany 83/171 Primary Examiner-A. Bartis Attorney, Agent, or Firm-Shlesinger, Fitzsimmons &amp; Shlesinger [57] ABSTRACT 1n order to be able to price-mark a product container,  
 which is wrapped in heat-shrinkable plastic film, without removing the film from around the container, a film burning element comprising a steel ring with a ceramic heating element in it is brought into contact with the film. The heated ring cuts and burns a circle in the film and simultaneously shrinks the film within the compass of the ring away from the rest of the wrapper so that when the steel ring is withdrawn. the cut-out portion of the wrapper drops away, leaving an area exposed for marking the price on the container, but otherwise leaving the wrapper intact.  
 1 Claim, ZDrawing Figures SHRINK-FILM HOLE-BURNING DEVICE The present invention relates to the price-marking of packages for sale in supermarkets, drugstores, and the like.  
  It is the practice when preparing packages for stacking on the shelves of supermarkets, drugstores, etc., for display and sale, to mark the individual packages with the price at which they are to be sold. The prices are stamped on the ends of cans or at convenient locations on pasteboard boxes, where the cashier or check-out employee can readily check the price. However, when the goods, which are to be sold are wrapped in cellophane or other plastic film, difficulties are experienced in marking. Of course, the cellophane wrapping can be removed; but often this is undesirable for sanitary reasons, or from the standpoint of preserving the freshness of the product. Moreover, frequently product containers, such as glass bottles holding condiments, or cosmetics, or other goods, are packaged in multiples in, for instance, a fibreboard tray wrapped in plastic shrink film. It is most undesirable to break such a package when storing it on a shelf for display and sale, among other reasons because the bottles may be intended to be sold, for instance, in pairs, and may get separated, or broken. Yet heretofore it has been virtually impossible to mark such containers without breaking the film wrapper.  
  A prime object of the present invention is to provide apparatus which will make it possible to price-mark film-wrapped containers without having to break plastic wrapping film.  
  Another object of this invention is to provide means which will enable the marking of such containers without breaking apart the package, which contains them.  
  Other objects of the invention are to provide apparatus of this nature, which will be fast in operation, simple, and relatively inexpensive.  
  Still other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in .conjunction with the accompanying drawing.  
 In the drawing:  
  FIG. 1 is a fragmentary vertical sectional view showing apparatus constructed according to one embodiment of the present invention for quickly and cleanly cutting through plastic wrapping film to expose on the product containers areas where the prices of the prod ucts can be price-marked, without disturbing the package; and v FIG. 2 is a fragmentary plan view of the cutting element for removing the film from the area at which each container is to be marked.  
  Referring now to the drawing by numrerals of reference, denotes a fibreboard container holding a plurality of bottles l2. l4 designates the shrink film which encloses the tray and the bottles and retains the bottles in the tray. The tray has die-cut holes 13 in its bottom, as shown in FIG. 1, through which a pricing stamp can be passed to mark the bottles when the covering shrink film is removed.  
  15 denotes generally apparatus made according to the present invention for cutting away those portions of the film at the bottom of the tray which register with the holes in the tray in order to permit marking the bottoms of the bottles with the price at which they are to be sold. This apparatus comprises a block 16 made of i insulating material and having, in the instance shown, two steel cutting rings 18 embedded therein. These rings are identical, and mounted in each is a ceramic heating element 20. Embedded in each heating element are two threaded electric terminals 22, 23 for conducting power to the electric heating coils 24 that are also embedded in the ceramic.  
  The block 16, in the instance shown, is fastened to the nut 26 that threads onto a piston rod 28 which is secured to a piston (not shown) that is reciprocable by fluid pressure in the air cylinder 30.  
  For use, the terminals 22 and 23 are connected to any suitable source of electrical power so as to heat the coils 24 and the ceramic blocks 20 and the steel rings 18 which contain those blocks. In use, the filmwrapped package containing the bottles, that are to be price-marked, is placed over or on the block 16; and the air cylinder 30 is actuated through valve means not shown so that piston rod 28 drives the heated steel rings upwardly to cut through the shrink film and cut out of it those portions 32 of the film which lie within the compass of the rings 18, and which register with the holes 13 in the fibreboard tray 10.  
  It takes but an instant to cut through the film 14; and as soon as the piston in the cylinder 30 is actuated to withdraw the cutters from the container, the cut-out portions 32, which have been heat-shrunk away from the rest of the film wrap, drop away leaving the desired areas on the bottoms of the bottles exposed to permit price-marking the bottles.  
  Obviously, the number of cutting elements can be increased to suit the number of containers, which are to be price-marked, that are packaged in a single package. Likewise, it is obvious that instead of providing a cutting apparatus with a plurality of cutting rings, a single ring device might be used, where bottles, or other containers are packaged individually.  
  While the invention has been described in connection with burning elements which are steel rings, it will be obvious that the rings may be made of any shape, viz., square, hexagonal, etc., and of other materials which can be heated sufficiently to cut through plastic wrapping film.  
  While the invention has been described, therefore, in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any embodiments of the invention which come within the scope of the invention, or the recital of the appended claims.  
 Having thus described our invention, what we claim 1. Apparatus for burning a hole in the heatshrinkable film wrapper of a product-container to leave an area exposed for marking the container comprising a block of insulating material,  
 a closed cutting ring mounted in said block and having one end protruding from said block to define an edge for engagement with the film wrapper,  
 a ceramic heating block mounted inside said ring below said edge and in contact with the internal periphery of said ring for heating the ring to a temperature sufficient to burn out of the film wrapper the portion of the wrapper circumscribed by the ring when said ring is in engagement with the wrapper,  
 an electric heating coil embedded in the heating block,  
 electric terminals embedded in the first-named block to conduct an electric current to said heating coil,  
 and fluid-pressure operated means for moving said first-named block toward and from the wrapper to move said ring into and out of engagement with the wrapper.