US20020168212A1 - On-demand label applicator system - Google Patents

Abstract

Improved label printing and applying apparatus (10) is provided which includes an improved digital printing assembly (12) having a rotatable impression drum (18) presenting an outer surface (20), as well as at least one digital print head (22) adjacent the drum outer surface (20). The overall apparatus (10) also includes a downstream label cutting and application assembly (14) having an adhesive applicator (32), laser cutter (40) and a label applying device (96). In use, a web (16) traverses the drum (18) with essentially no relative movement between the web (16) and drum surface (20), and the print head(s) (22) are actuated to form images on the web (16), which may be identical or varied. Thereafter, the printed web passes into and through the assembly (14) where adhesive is applied, the individual images are laser cut, and the labels are thereupon applied to products (54).

Description

BACKGROUND OF THE INVENTION
• 1. Field of the Invention[0001]
• The present invention is broadly concerned with label printing and applying apparatus, and corresponding methods, wherein images such as labels are successively printed on a continuous web using a relatively large rotating impression drum and associated digital print heads; thereafter, the printed web passes through a downstream adhesive applicator and a laser cutting and label application assembly where the individual printed images are laser cut and applied to products. More particularly, the invention is concerned with such apparatus and methods wherein use of an improved drum/digital print head printing assembly which permits high speed, on-demand production of images for labels or the like, using relatively inexpensive, thin, lightweight webs.[0002]
• 2. Description of the Prior Art[0003]
• Traditionally, pressure sensitive labels have been produced using more or less standard, multiple-tower web-fed printing apparatus followed by mechanical die cutting of the individual labels. In such operations, it has generally been necessary to releasably adhere the printed web to a carrier sheet so as to permit die cutting of the labels. Once the labels are cut, the matrix is removed from the carrier, leaving the labels spaced on the carrier sheet which was then formed into a roll. Carrier sheets of this type typically represent nearly one half of the material cost of label production. This is a tremendous waste of resources, and the spent carrier sheets also present an on-going trash disposal burden, typically ending in landfills.[0004]
• In response to these problems, it has been suggested in the past to employ laser cutting devices in lieu of traditional die cutting systems. Moreover, some laser cutting systems are “linerless” in that the use of carrier sheets is eliminated. For example, U.S. Pat. No. 5,681,412 describes a modern-day laser cutting label production system of this type.[0005]
• While such laser systems are a significant advance in the art, some problems remain. For example, the upstream printing of label stock prior to laser cutting has not heretofore been seriously addressed in prior laser-based systems. That is, traditional printing methods, be they either web fed multiple-tower printers or even digital printing equipment, it is usually necessary to employ relatively thick webs having sufficient mechanical strength to withstand the printing operation. Rollers or other devices used to pull the webs through these printing units impose significant stresses on the webs, and if the webs are too thin or otherwise insufficiently strong, the webs have a tendency to break and/or elongate which is inimical to consistent quality printing. As a consequence, it has generally been necessary to employ web having a thickness of at least about 2 mils. These webs are relatively expensive, as compared with thinner webs of, e.g., 0.5 mil thickness.[0006]
• It has also been suggested to avoid intermediate collection of printed and cut labels by use of in-line, complete systems wherein a starting label stock is printed, adhesive is applied, and the cut stock is applied to products. Here again though, these systems suffer from many of the foregoing problems. Furthermore, such complete systems lack desirable on-demand characteristics i.e., the use of conventional printing equipment makes it very difficult to rapidly shift between different types or styles of labels, and cannot produce infinitely variable label copy and shape.[0007]
SUMMARY OF THE INVENTION
• The present invention overcomes the problems outlined above and provides improved label printing and application apparatus especially (although not exclusively) suitable for label making coupled with immediate in-line application of the labels to products. Broadly speaking, the label printing and applying apparatus of the invention includes a web printing assembly operable to print individual label images on a continuously moving web, where the images may be successive or identical, or variable image-to-image. The apparatus includes a rotatable impression drum presenting an outer surface and at least one (and usually plural) digital print heads adjacent the drum outer surface. A downstream web cutting and applying assembly including a laser cutter and a label application device also forms a part of the overall apparatus. Finally, a web guidance system operable to guide a continuous web around at least a portion of the drum surface and between the drum surface and print head(s) is provided, allowing printing of successive images on the web. In practice, with the apparatus of the invention, use can be made of relatively thin, inexpensive webs. This stems from the fact that during printing, the linear speed of the web and the speed of the impression drum surface are closely matched so that there is essentially no relative movement between the drum surface and web. Consequently, the web is stabilized during printing and is not subjected to undue tension or forces which would otherwise distort the web. By the same token, use of digital print heads and associated sensors permits very accurate registration printing so that high quality images can be produced.[0008]
• In preferred forms, the print head may be inkjet or laser print head, or any other suitable digitally-controlled printing device. The impression drum is preferably rotatable in opposite directions as desired, so that either side of a web may be printed.[0009]
• Various types of label-applying devices can be used in the invention, such as rotary or inline units. The only qualification is that a given device be capable of picking up the successive laser cut label images and transferring onto respective products.[0010]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a schematic representation of the improved digital web printing, adhesive application, laser cutting and labeling apparatus of the invention, particularly designed for the on-demand production and application of labels to end products;[0011]
• FIG. 2 is a view similar to that of FIG. 1, but illustrating in enlarged format the downstream web handling and labeling portion of the FIG. 1 apparatus;[0012]
• FIG. 3 is a view similar to that of FIG. 1, but illustrating in enlarged format the upstream web printing portion of the FIG. 1 apparatus;[0013]
• FIG. 4 is a schematic representation of another type of digital web printing and labeling apparatus in accordance with the invention, illustrating an alternate path of travel for the continuous web permitting reverse side digital printing, and/or application of clear laminate over digital printing;[0014]
• FIG. 5 is a schematic representation of another embodiment of the invention, wherein the printing assembly makes use of a pair of serially related, servo-driven gearless impression drums;[0015]
• FIG. 6 is a schematic representation of a still further embodiment of the invention, depicting another type of labeling apparatus, as compared with the embodiments of FIGS.[0016]1-5;
• FIG. 7 is a schematic representation of a still further embodiment of the invention, depicting another type of labeling apparatus, as compared with the embodiments of FIGS.[0017]1-6; and
• FIG. 8 is a schematic representation of a still further embodiment of the invention, depicting another type of labeling apparatus, as compared with the embodiments of FIGS.[0018]1-7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• Turning now to the drawings, and particularly FIG. 1, a web printing and[0019]labeling apparatus10 is illustrated in a configuration especially adapted for the production and application of product labels. Theapparatus10 includes a digital print-ing assembly12 and a downstream web cutting, handling andapplication assembly14. Theapparatus10 is designed to accept acontinuous web16 and to print individual images (e.g., labels) on theweb16, followed by adhesive application, laser cutting of labels and application of cutting and the cut labels. A feature of the invention is the use of a digital printing assembly and a relativelylarge impression drum18, thereby permitting use of lightweight, thin, relatively low cost webs.
• In more detail (see FIG. 3), the[0020]printing assembly12 includes a relatively large (at least about 3 feet in diameter and more preferably from about 4-6 feet in diameter)impression drum18 presenting anouter surface20. Thedrum18 is mounted for controlled rotation in either direction, i.e., clockwise or counterclockwise, by means of servo-driven gearless electronic drives (in this content “gearless” refers to the fact that thedrum18 does not have a peripheral gear as is common with typical gear train-driven drums). Thus (see FIG. 1), thedrum18 is rotatable on acentral shaft19, which is coupled with a servo-drive19a. Furthermore, the drum is provided with internal passageways for cooling media such s chilled water or the like. Theoverall assembly12 further includes at least one, and preferably a plurality ofdigital print heads22. As shown in FIG. 1, a total of eightprint heads22a-22hare provided in circumferentially spaced relationship about and adjacent tosurface20 ofdrum18. Theprint heads22 can be any one of a number of digitally operated devices, such as inkjet, electrophotographic, ion deposition, elcographic, magnetophotographic, direct thermal, thermal transfer, and digital offset print heads. It will be appreciated that each such print head is individually driven and electronically controlled, which may include a servo-drive if needed.
• In preferred practice, most of[0021]print heads22 have an associatedphotosensor24, in the case of FIG. 1,sensors24a-24g. Similarly, the print heads have adjacent UV or EB (electron beam) curingdevices26, as shown in FIG. 1, thedevices26a-26f. Finally, it will be observed that additional UV/EB curing devices28 and30 are located about the periphery ofdrum18.
• The web cutting and labeling assembly[0022]14 (see FIG. 2) includes a digitally operatedadhesive application device32, which can provide either sequential application of the adhesive or flood-coating as desired. Arotatable chill roller34 is located downstream ofdevice32, and has an opposed UV/EB or other curing/drivingcuring device36. A scanning camera (typically a CCD camera)38 is located downstream of thechill roller34, and use may also be made of anoptional camera38′ as shown. Similarly, aconventional laser cutter40 is disposed downstream of theroller34 but on the opposite side ofweb16 as illustrated.
• The labeling portion of[0023]assembly14 includes a vacuum-type label conveyor42 as well as an adjacent, rotatable, productlabeling star wheel44, the latter having aninput conveyor46 for delivery of unlabeled products to thestar wheel44, and anopposed output conveyor48 for take away of labeled products. An optional EAS (electronic article surveillance)device50 is located along the length ofconveyor42 and upstream ofstar wheel44, in order to print or apply an EAS tags or other identifying indicia to laser cut labels52 prior to application thereof. Asensor51 associated withdevice50 is employed to assure that the EAS tags are applied only to properly cut labels. As explained more fully below, the finished labels are applied toproducts54 coming into and out ofstar wheel44.
• The[0024]overall printing assembly12 further includes aweb guidance system56 which is operable to guideweb16 around at least a portion ofdrum surface20 and between the latter and print head(s)22 for printing of the outer face ofweb16 with a series of label images; thesystem56 also serves to guide the printed web into and through theassembly14. In detail, theguidance system56 includes a pair of alternately usable unwindrollers58 and60 (see FIG. 4), asupport roller62, and a pair of servo-drivenrollers64,66 located on opposite sides of thedrum18. An infeed niproller68 is positionedadjacent servo roller64 and forms, withsurface20, an infeed nip withweb16. In like manner, an exit niproller70 is locatedadjacent servo66, and forms withsurface20 an exit nip forweb16. In preferred practice, thesystem56 also includes one or moreadditional support rollers72,photosensor74 and an additional, optionally usable,heatable laminating roller76. Finally, thesystem56 includes a matrix niproller78 adjacent and upstream ofapplicator50, together with a matrixweb takeup roller80.
• Although not shown in detail, it will be appreciated that the operation of[0025]apparatus10 is microprocessor controlled. That is, thesensors24 and74,camera38, print heads22, curingdevices24,28 and30,device32, laser cuter40 and thedrum18, as well asconveyor42,star wheel44,EAS device50 andsensor51 are all operatively coupled with microprocessor(s). Such microprocessor operation is controlled via known software, such as that commercialized by Wave Front Technologies of Irvine, Calif.
• In the ensuing discussion, the operation of[0026]apparatus10 for label production and application will be explained; it should be understood, however, that theapparatus10 may be used in production and application of other printed articles.
• In the course of preparing labels using the[0027]apparatus10, a starting web roll is mounted on unwindroller58 and is threaded aroundrollers62,64 and68, and about thesurface20 ofdrum18. The web is further trained aroundrollers70 and66, and overrollers72 and76. Finally, the web is trained about niproller78 for ultimate takeup onmatrix takeup roller80. During the printing and labeling operation, thedrum18 is rotated at a predetermined speed and theweb guidance system56 is operated to likewise move theweb16 around thedrum18 and through the remainder of theapparatus10. In this connection, it is desired that the speed ofdrum surface20 be essentially equal to the linear speed of theweb16, i.e., there is essentially no relative movement between thesurface20 andweb16 between the niprollers68,70. This is ensured through control of the rotational speed ofdrum18, and control of web speed viasystem56. In the latter case, theservo rollers64,66 provide on-the-go tension and speed control for theweb16. As theweb16 traverses theweb surface20 between the niprollers68,70, theprint heads22a-22hare operated to successively print label images onto the outer surface of the web. As will be readily understood, each of the heads can be designed for printing a respective color so that the final printed images may be multi-colored to any desired extent. The operation of the print heads is controlled via thesensors24. In the usual practice,web16 is provided with fiducials or other eye marks adjacent or associated with the image-bearing regions of the web, and these are sensed by thesensors24 so as to insure proper registration between the printing performed by each of the printing heads. In order to provide the highest quality printing, theindividual curing devices26,28,30 are also operated during rotation ofdrum18. This serves to cure images or parts thereof deposited by the respective digital print heads22.
• As the[0028]web16 leaves drum18, it has printed thereon the desired spaced label images. The web then traverses therollers72,76 with intermediate sensing bysensor74. Next, the web entersassembly14 and is adhesive coated bydevice32. In this connection, a feature of the invention is the ability to reverse print on a clear thin film face of theweb16 and then apply adhesive over the printing. This serves to “bury” the image so as to produce a higher quality label. As indicated previously,device32, under microprocessor control, can be used to apply adhesive only to regions of the label images, or alternately, the web surface may be flood-coated.
• After adhesive application, the[0029]web16 proceeds through a station defined bychill roller34 and opposed curingdevice36. This serves to fully cure and dry the adhesive applied upstream by thedevice32.
• Next, the printed label images are scanned by[0030]camera38 so as to insure that they are all of appropriate quality. All such approved images are next laser cut using thecutter40 and proceed toEAS device50 for application of an identifying tag or the like; as noted above, the operation ofdevice50 is monitored bysensor51, to ensure that tags are applied or printed only to properly cut labels. This produces a series ofindividual labels52 which are picked up by the vacuum operation ofconveyor42 for conveyance to starwheel44. At the same time, the uncut remainder of theweb16, in the form of a matrix16a, is taken up bytakeup roller80.
• The individual labels[0031]52 carried byconveyor42 proceed to the area ofstar wheel44 where such labels are applied to theproducts54. In particular, it will be observed that thestar wheel44 is operated in timed relationship with theconveyor42, so that the presentation of theindividual products54 atlabel applying location82 coincides with presentation and release of anindividual label52. In this fashion, each of thearticles54 is sequentially labeled at thelocation82.
• In the event that one or more label images of inferior quality are detected by[0032]camera38, the microprocessor controllersignals laser cutter40 to not cut such inferior label images. Therefore, such inferior images form a part of the matrix web16aand are collected ontakeup roller80 along with the cut matrix. By the same token, the operation ofstar wheel44 would be stopped temporarily until acceptable cut labels52 are again ready for application to products.
• FIG. 4 depicts an[0033]apparatus84 very similar toapparatus10 and including aprinting assembly12 and a laser web cutting andlabeling assembly14. For ease of discussion, like components will be similarly numbered between FIGS. 1 and 2, and thecomponents19,19aare not specifically shown. It will be seen, however, that theweb16 noted on alternate unwindroller16 and thus proceeds an opposite direction aboutsurface20 ofdrum18. By the same token, in this embodiment, thedrum18 is rotated in a clockwise direction, as compared with the counterclockwise direction of FIG. 1. Use of the alternate unwindroller60 allows the opposite side ofweb16 to be printed, as compared with the FIG. 1 embodiment. Also as shown in this embodiment, laminatingweb86 may be applied to the printed face ofweb16 prior to entrance thereof into theassembly14. To this end, theweb86 is mounted on primary unwindroller58 and is applied by heating oflaminating roller76.
• The operation of[0034]apparatus84 proceeds in exactly the same fashion as that described with reference to FIG. 1, with the exception that thelaminating web86 is applied to the printed face ofweb16.
• FIG. 5 illustrates a still further apparatus in accordance with the invention which is very similar to that shown in FIG. 4 (again, the[0035]components19,19aare not specifically depicted). However, in this case, anadditional printing drum90 with associated print heads22,sensors24, and UV/EB curing devices is provided in the web path, prior to entrance of the web into the cutting and handlingassembly14. The purpose of theadditional drum90 and associated devices is to permit high speed operation through greater printing capacity. Also, the additional-print head allow further colors to be applied, as compared with use of only a single printing drum.
• FIGS. 6, 7 and[0036]8 depict additional embodiments with different types of label-applying apparatus; in each case, use may be made ofupstream printing apparatus12 of any of the previous embodiments, or for that matter other embodiments within the scope of the invention. In each of FIGS.6-8, like components from the earlier embodiments are identically numbered and are not further described.
• Turning first to FIG. 6, a label-applying[0037]assembly92 includes a pair of pitched, adjacent vacuum or staticelectric conveyors94 which extend from a pointadjacent cutter40past roller78 andapplicator50, to a label-applyingstation96. Theright hand conveyor94 as viewed in FIG. 6, supports the web during the cutting operation, whereas theleft hand belt94 moves at a faster speed than the right hand belt and delivers the cut labels to the label-applyingstation96; the speeds of thebelts94 are correlated so as to deliver the cut labels in proper timed relationship to thestation96, for application thereof to product. Aconveyor98 carrying individual, spaced apartproducts54 intersects with the end ofconveyor94 as shown. In the case of FIG. 7, asecondary vacuum roller100 is provided downstream ofcutter40 androller78, and it will be seen that thelabels52 are conveyed by theroller100 to apickup conveyor belt102, which again may be vacuum operated or a static electric belt. Thesiliconized belt102 is trained aroundrollers104,106 andelongate applicator tip108. Aproduct conveyor110 carryingindividual products54 intersects with the end ofbelt102 remote fromroller100. In use, cut labels52 are released byroller100 at the juncture thereof withbelt102, and the latter serves to convey the individual labels to alabel applying station112. At this point, thelabels52 are applied torespective products54. Finally, in FIG. 8, an unwindroller114 andtakeup roller116 are provided, with aintermediate roller118 therebetween, the latter oriented close tovacuum roller100. Asupport roller120 andapplicator tip122 are positionedadjacent roller116 as shown. Aliner web124 from a supply thereof extends fromroller114 and is trained aboutintermediate roller18,tip122,roller120 and is finally taken up onroller116. When theweb124 is fully wound onroller116, it can be transferred toroller114 for reuse. In practice, cut labels52 are conveyed by theroller100 as in the case of the FIG. 7 embodiment, but are transferred to theweb124 to the label-applyingstation126. At this point, theproducts54, conveyed byconveyor128, are labeled as shown in FIG. 8.
• The apparatus and methods of the invention allow the user to produce variable, on-demand, on-the-go graphics and apply high quality labels or other images using relatively low cost web material. That is, inasmuch as the[0038]web16 is printed while traversing the drum18 (and drum90 in the case of FIG. 5), the web is fully stabilized during the printing operation.
• The speed of the web is consistent with the speed of the drum due to the web being in contact with the drum's surface. Only a small amount of tension is applied to the web during travel thereof past the digital printing stations while the web's in contact with the drum. This is to in contrast with conventional in-line systems wherein material with greater internal tensile values, which increases thickness and/or cost, must be employed in order to avoid web breakage or elongation during web travel through the in-line printing and converting process. Furthermore, the use of microprocessor-controlled digital print heads allow for consistent high quality printing over a wide range of speeds.[0039]
• While the foregoing embodiments depict the use of webs with adhesive application during processing, webs previously coated with a cured, activatable adhesive could also be employed, thus eliminating the need for in-line adhesive application.[0040]

Claims (27)

We claim:

1. In apparatus including a web printing assembly operable to print individual images on a continuously moving web, and a web cutting and applying assembly having a laser cutter operable to cut the individual images from the continuously moving web and an applicator for handling the laser cut images and applying the laser cut images, an improved web printing assembly comprising:

a rotatable impression drum presenting an outer surface;

at least one digital print head adjacent said drum outer surface; and

a web guidance system operable to guide a continuous web around at least a portion of said drum outer surface and between the drum outer surface and printhead for printing of the web with said individual images, and to thereafter guide the web into said web cutting and handling assembly.

2. The apparatus ofclaim 1, said print head being selected from the group consisting of inkjet, electrophotographic, ion deposition, elcographic, magnetophotographic, direct thermal, thermal transfer and digital offset print heads.

3. The apparatus ofclaim 1, including a web curing apparatus proximal to said print head to cure said images after printing thereof.

4. The apparatus ofclaim 1, including an image sensor adjacent said print head for sensing of said images after printing thereof.

5. The apparatus ofclaim 1, including a plurality of digital print heads disposed in a circumferentially spaced relationship about said drum surface.

6. The apparatus ofclaim 5, there being a web dryer associated with each of said print heads respectively.

7. The apparatus ofclaim 5, there being an image sensor associated with each of said print head respectively.

8. The apparatus ofclaim 1, there being a pair of said impression drums each having at least one respective digital print head associated therewith, said web guidance system operable to guide said web in serial order around at least a portion of the circumference of each drum surface and between each drum surface and the associated print head for printing of successive images at each drum.

9. The apparatus ofclaim 1, said web guidance system comprising:

a pair of nip rollers located at circumferentially spaced locations about said drum surface and defining, with the drum surface, a web infeed nip and a web exit nip;

a servo roller adjacent said web infeed and web exit nips respectively for tensioning the web and maintaining the desired speed thereof.

10. The apparatus ofclaim 1, said laser cutter producing a stream of cut images and a waste matrix, said web guidance system including a takeup roller for taking up the waste matrix.

11. The apparatus ofclaim 10, said cutting and applying assembly including:

a shiftable transfer member located to pick up and support said laser cut images, and to transfer the images to an application station; and

a product conveyor operable to move successive products into and through said application station for application of cut images thereto.

12. The apparatus ofclaim 11, said transfer member comprising a conveyor belt.

13. The apparatus ofclaim 11, said product conveyor comprising a rotatable star wheel configured for receiving individual products and moving such products into said station for application of said images thereto, and for thereafter moving the products away from the station.

14. The apparatus ofclaim 11, said product conveyor comprising a product-supporting conveyor operable to move said products along a generally rectilinear path into said station for application of said images thereto, and for thereafter moving the products away from the station.

15. The apparatus ofclaim 1, including an adhesive applicator for applying adhesive to the web at the regions of said images thereon.

16. The apparatus ofclaim 1, said printed images being label images.

17. The apparatus ofclaim 1, said web printing assembly operable to permit printing where at least certain of said images are different from other of said images.

18. The apparatus ofclaim 1, said impression drum being selectively rotatable in opposite directions.

19. The apparatus ofclaim 18, including a servo-motor operably coupled with said impression drum.

20. A method of printing a continuous web with printed images, and thereafter cutting the images from the web and applying such images to products, said method comprising the steps of:

providing a printing assembly including a rotatable impression drum presenting an outer surface, and at least one digital print head adjacent said drum surface;

guiding a continuous web around at least a portion of said drum outer surface and between the drum outer surface and the print head, and operating the print head to successively print said images on the moving web;

laser cutting the successive printed images from said moving web; and

applying said cut images to products.

21. The method ofclaim 20, including the step of rotating said drum and guiding said web such that when said web is passing around the drum there is essentially no relative movement between the drum surface and the web.

22. The method ofclaim 20, including the step of at least partially curing said successively printed images after printing thereof.

23. The method ofclaim 20, including the steps of providing a plurality of print head disposed about said drum surface, guiding said web between the drum surface and each of the print heads, and operating the plural print heads to each print upon the moving web.

24. The method ofclaim 20, said applying step comprising the steps of moving said cut images to an application station, moving products into said station, and applying the cut images to the products in the application station.

25. The method ofclaim 20, said printed images being label images.

26. The method ofclaim 20, including the step of printing at least certain of said images different from other of said images.

27. The method ofclaim 20, including the step of selectively rotating said impression drum in opposite directions.

Images