US2524946A - Labeling machine and method using labels coated with thermoactivatable adhesive - Google Patents

Description

Oct. 10,1950 s. w. VON HOFE 2,524,946

LABELING MACHINE AND METHOD USING LABELS COATED II'I'H Tl-IERIIOACTIVATABLE ADHESIVE Filed 1m. 1a. 1945 4 Sheets-Sheet 1 INVENTOR.

Av-v-omws K Oct. 10, 1950 s. w. VON HOFE 2,524,946

v mums ncums AND METHOD usmc mans comm um mmumcnvnmm ADHESIVE Filed Dec. 18. 19

4 Sheets-Sheet 2 IN VEN TOR.

M Van Hm? AT'TcmA/EK Geo/ye Oct, 10, 1950 s. w. VON HOFE LABELING ncnm: AND METHOD usmc mans comma urn-x 'Il'lERlIOACTIVATABLE ADi-lESIVE Filed Dec. 18. 1945 4 Sheets-Sheet 5 Geo/ye Mi o)? I967? mmvron ATro/v/w Oct. 10, 1950 e. w. VON HOFE 2,524,946

mamas ucum: AND us'mon usmc ums comm arm muoAcm-xvxmsm ADHESIVE Filed Dec 18. 1945 4 Sheets-Sheet 4 Geo/ye [41/00/70]? INVENTOR.

Patented Oct. 10, 1950 LABELING MACHINE AND METHOD USING LABELS COATED WITH THERMOACTIVAT- ABLE ADHESIVE George W. von Hofe, Bound Brook, N. J assignor to New Jersey Machine Corporation, Hoboken, N. J., a corporation of New Jersey Application December 18, 1945, Serial No. 635,657

Claims. (Cl. 216-29) The invention relates to a labeling machine and method using labels coated with thermo-activatable adhesives.

In practice, such adhesives are activated by the application of heat to transform the same from a normal, non-adhesive condition to an adhesive state in which the coatings serve to adhesively attach said labels in place in a manner to carry out the functions thereof. Because of the character of the thermo-activatable adhesives, it is desirable to provide a time interval in which proper tackiness of the activated-adhesive coatings may be developed.

The invention has for its object to provide a novel machine wherein provision is made for activating the adhesive coatings in a simple manner with maximum efliciency.

A further object of the invention is to provide severing means in the novel machine whereby a traveling web of paper, coated with the activatable adhesive, is cut into sections comprising wrappers, labels, and the like.

In addition, the invention provides applying mechanism operating in efilcient association with the activating means for applying the adhesivelycoated sections in adhesive connection with articles in accordance with the predetermined functions of said sections.

Other objects will appear from the description hereinafter, and the features of novelty will be pointed out in the claims.

In the accompanying drawings which illustrate an example of the invention without defining its limits,

Fig. 1 is a side elevation of a machine constructed in accordance with the principle of the invention;

Fig. 2 is a sectional detail on the line 2-2 of Fig. '1

Fig. 3 is a detail side elevation of the means for pressing the sheet, label or the like into contact with an article;

Fig. 4 is a front elevation of the structure shown in Fig. 3;

Fig. 5 is a front elevation illustrating the applying means, strip severing, and intermittent feeding mechanism which comprises the left side or half of a machine;

Fig. 6 is a front elevation showing the continuously-operating web-feeding mechanism mounted at the right hand end of the machine;

Fig. 7 is an enlarged detail taken on the line l--'l of Fig. 6, and

Fig. 8 is a section on the line 8-8 of Fig. 1.

In accordance with the present invention, 1

provide an installation which includes means for activating normally-inactive adhesive material with which one of the surfaces of a strip or strips of paper is coated, said strip or strips being preferably fed from a roll or rolls in web form, to the mechanism which, in the illustrated ex.- ample, performs the applying operation. In the machine shown in the drawing, blanks in folded conditions are placed manually by the operative upon a form or core; after which, a foot pedal or other manually-operable device is actuated by the operator to cause the applying mechanism to perform its complete cycle of. operations. As such mechanism performs its functions, the paper is fed by an intermittent feeding device that engages the gummed side of the web of paper, and advances it to the article to be labeled. In

the meantime, the supply of coated paper is continuously fed into operative relation with the activating means whereby said adhesive coating is heated and thereby transformed from its normal adhesively-inactive condition to an activated adhesive state. A strip severing means is actuated in predetermined-timed relationship with the wrapping mechanism to sever from the web a section of paper of the proper length for application to the article, for instance, as a wrapper or as a label. The successful operation of the instant machine depends in a large measure upon the presentation of the strip with the activated adhesive thereon in such condition'that, when the section is applied to the article, the adhesive coating thereof will be in the proper tacky condition to adhere properly to said article. In order that this condition may be attained, the activation of the adhesive coating takes place at a predetermined distance from the applying mechanismso that a certain time interval will elapse between activation of the adhesive coating material and application of the label to permit said activated coating material to develop a degree of maximum adhesiveness; with this arrangement, a length of adhesively-coated paper is, in effect, stored for a time to permit the conditioning of the activated-adhesive coating material and paper in order to prepare the same for application at the applying station. With the instant machine, the aforesaid time interval may vary considerably due to the fact that the placing of the article upon the form and the actuation of the foot pedal or other device which causes the applying mechanism to start functioning, is performed manually. Furthermore, as the operative must, from time to time, remove the article subsequent to the application of the aforesaid sections of paper and secure a new supply of articles, there are times when the time interval between the activation step and the application of the strip may be of relatively long duration. In any case, however, this time interval is of such duration that the activated coating of adhesive will reach a state of maximum adhesiveness by the time the applying station is reached.

The installation, shown by way of example in the accompanying drawings will first be described briefly. It includes a suitable support, connected to the main frame of the machine, upon which a web or webs of paper are mounted, preferably in the form of rolls. The web or webs is or are withdrawn from the roll or rolls to a continuouslyoperating web-feeding mechanism, which functions to pull the web or webs from the roll or rolls. The web then passes to a web tensioner and thence to an intermittent feeding mechanism which conveys the end of the activated web to the labelin mechanism. Located between the intermittent feeding device and the labeling mechanism is a strip severing means which is automatically operated in timed relationship with the labeling and. the intermittent feeding device, to sever from the web a strip of paper of the proper length to constitute, for instance, .a label 4 having a pulley I5 secured thereto by which the machine may be driven from a line shaft or from an electric motor I8, supported upon a shelf or bracket formed integrally with, or secured to, the base I0.

Mounted in suitable bearings in the brackets II and I2 is a tubular shaft l8 (see Figs. 1 and 2), having detachably secured to the front end thereof a core or form IS; the core is in the shape of a rectangular prism and is dimensioned according to the size of the articles to be labeled or wrapped. Mounted within the tubular shaft is a solid shaft or rod 20, which has secured to its front end an ejecting plate 2 I. The shaft 20 is supported at its ends by sleeves 22, 23, which are interposed between said shaft and the tubular shaft |8. The tubular shaft l8 has slidably secured thereto an intermittent gear 24 having a sleeve-like extension 24-11 which passes through and is rotatably mounted in a bearing formed adjacent to the upper end of the bracket l2.

Meshing with the gear 24 is a cooperating, intermittent gear 25, secured upon a cam shaft 26; said cam shaft being rotatably supported in suitable bearings, provided in the brackets l I and I2, below the tubular shaft l8. Secured to the cam shaft 25 adjacent to the bracket II is a gear 21 which meshes with and is driven by the gear 28,

for the sides of the boxes. The labeling mechanism comprises a block, or.,core, as. it is commonly called, which core is shaped and dimensioned according to the shape and size of the article to be labeled. This core has associated therewith means for holding the article in position upon the core during the performance of the machine's cycle of operations. As the end of the activated paper web is fed to the labeling station, its activated side is moved, by an automatically-operated.roller, into engagement with an artic e, which has been placed upon the core by the o erative and the core is rotated. Duri112 the rotation of the core. said roller holds the web of paper in contact with the sides of the article upon the rotating core, thus pressing the activated stri upon the sides of the blank. During the rotation of the core, the engagement of the web between the roller and blank causes the web to be drawn into the labeling mechanism.

lution, the strip-severing means, above? referred mounted upon a jack shaft 29, said jack shaft .bein driven from the mainshaft l4 by means of'the-gearing 30. Mounted upon the cam shaft 26 is a main cam 3|, provided with a cam groove 32, in which is engaged a roller 33. The roller 33 is mounted on an oscillating lever 34, between the ends of said 'jecting end of the cam shaft 26. This cam is in the form of a crank arm and is provided at its outer end with a cam face 42, adapted to engage to, is actnatedto sever from theweb a label of.

a desired length to roperly label the article. 'aAt at certain parts of its revolution with a cam roller 43. Thecam roller 43 is mounted upon a laterally projecting arm .44, formedj'integrally with the the end of a complete revolution of the core,-.' it advances and the work is removed by the operative.

For convenience and clarity of description, the machin will be described in detail under the following headings;

The labeling mechanism-A.

meansB. y The intermittent feeding device-C. The strip severing means-D. Operation.

APPLYING MECHANISM-A (Frcs l r0 4, INCLUSIVE.)

sleeve 23 hereinbefore referred to. A spring 45 is'mount'ed within the tubular shaft I8 and is coiled about the shaft or rod 20. This spring has one end thereof in engagement with the inner end of the sleeve 23 and its other end in engage-- ment with an abutment 46, fixed within the tubuc0 Paper sup lying, activating, and tensioning lar shaft l8, thus serving normally to urge the rod. 20, with the ejecting plate 2| thereof, towards'the left in Fig. 2 of the drawings. In this position, it will be noted that the ejecting plate core Hi.

2| is in'alig n'ment with the front end of the Suitably secured to the front end of the tubular shaft l8 andhe'ld' fixed against movement relatively thereto; is a bracket 53, having a pair of diametrically-opposed bearing bosses 5|, in each of "which is mounted a pivot vlpin 52. Each pivot pin 52 serves as a pivotal support for a lever 53, both ends of which are yoked. One of these yoked ends, as will be seen from Fig. 1, straddles the boss 5| and the other yoked end carries a pin 54-a, the ends of which project outwardly beyond the sides of the yoked lever for a purpose which will presently appear. Between the yoke jaws of the lever said pin has rotatably supported on it a roller 54. The roller 58 engageswith a slide cam 55, secured to the sleeve 22, which sleeve as heretofore described is secured to the sliding shaft or rod 28.. Secured to the yokedend of the lever 53, which straddles the boss is a bar 58, preferably provided with a plurality of spaced holes 51, in which the finger carrying arms 58 are adapted to be secured by any suitable means, such as the bolts 59. Each of the finger carrying arms 58 carries at its outer end a gripping finger 58, which fingers are adapted, in certain positions of the core l9, to project over and engage with an article placed upon the core. In order to ina counterclockwise direction, Fig. 4, to hold said I roller 82 in engagement with the core l9, by the.

sure that the gripping fingers 88 will engage the article with sufficient force to hold said article securely upon the core l9 the similarly located projecting ends of the ptis 54--a carried by the forward ends of the levers 53 are connected by tension springs 54-h, said springs also serving to hold the rollers 54 in engagement with the slide cams 55. When the slide cams 55 move rearward'y due to the roll 43 falling off the segment 42, the rollers 54 are forced by the springs 54- 11 to follow the drop of the cams. The parts are so constructed that before the rollers 54 reach the lowermost points of the cams the fingers 88 will engage the article, the springs 54-h thus holding said fingers 58 under tension and in engagement with said article. In order to adjust the position of the gripping fingers B8 relatively to the tubular shaft to compensate for cores of different sizes, the finger-carrying arms 58 are provided at their outer ends with an elongated head 58--a, having a p'urality of spaced-holes 58--b therein, and the fingers 88 are secured to a bracket 8|, which in turn is secured by means of a screw 5l -a adapted tobe screwed into one of the spaced holes 58-b. I

As hereinbefore set forth in the brief description of the machine, the paper strip has its activated side moved into engagement with the article by means of a mechanically actuated roller. This roller is most clearly shown in Figs. 3 and 4 of the drawings and is indicated by the reference character 82. It is rotatably mounted between the arms of a yoke member 83, the latter being secured at the outer end of a bar 64. The bar 84, which, as clearly shown in Fig. 3 of the drawing, is of rectangular cross section, is mounted for longitudina sliding adjustment within the rectangular bore of a sleeve or bushing 85, mounted for rotatable adjustment in the boss 68 of an oscillating bracket 81. The'sleeve 85 is provided with an enlarged end or head 88, having formed integrallv therewith at its upper end a pair of transversely spaced lugs 69, each of said lugs having screwed therein an adjusting set screw 18. The ends of said set screws are adapted to engage with a lug 1|, projecting upwardly from the top of the bracket 81. A locking bot I2 is screwed into the lug II and passes through an elongated slot in the upper end of the enlarged head 88 of sleeve 85 and serves to lock said sleeve in adjusted position. For the purpose of securing the bar 64 in adjusted position longitudinally of the sleeve 85, a set screw 13 is provided. The oscillating bracket 61 is provided with a depending boss II, which extends transversely of the boss 85 and is mounted upon a shaft 15, supported in bearings 18, provided at the upper ends of the arms of a yoke shaped bracket 11, the latter being secured to base In. The oscillating bracket 81 is normally urged in action of a coiled tension spring 18, one end of which is secured to the lower end of a rod 19, secured to a ratchet segment 88 presently to be described. At predetermined intervals, the bracket 81 is intermittently actuated from the cam shaft 26 by means of a pawl 8|, which en gages with the ratchet segment 80, the latter being formed integrally with the oscillating bracket 81, and depending from the boss H thereof. The pawl 8| projects from a boss 82, rotatably mounted upon a short shaft 83, carried in a bearing 84 of a bracket 85, supported by means of the boss 86 upon the shaft 15, this shaft being the one upon which the transverse boss I4 of the oscillating bracket 81 is mounted. The boss 82 has a pair of upwardly projecting arms 81, 88, the arm 81 having secured thereto one end of a spring 89, the other end of which is secured to a lug projecting laterally from the bracket 85, and said spring serving to hold the pawl 8| normally in engagement with the ratchet segment 88. Thearm 88 just referred to iS adapted to engage with an adjustable stop 90, secured in the bracket IT, to cause the pawl 8| to become disengaged from the ratchet segment at proper predetermined times. The short shaft 83 passes through a boss 9|, at the lower end of a cam yoke 92, the upper end of which is in engagement with the cam shaft 28 and is caused to be oscillated by means of a cam and roller (not shown).

The construction just described enables a very accurate adjustment of the roller 62 relative to the article to be secured and presents a marked improvement over existing constructions.

The main shaft M of the machine is preferably rotated continuously and the actuation of the various parts is effected from the cam shaft 26.

Rotation of the cam shaft is controlled by a one revolution clutch which is adapted to be thrown into operation by the depression of the pedal 93. After the cam shaft has completed a full revolution, during which the applying mechanism has performed its full cycle of operations the clutch is caused to be automatically disengaged. As

shown in Figures 1 and 8, the one revolution clutch is a clutch of the knife-edged type and consists of an arm 94, one end of which is pivotally mounted upon a laterally projecting boss of the bracket II. The other end of said arm is adapted to rest by gravity upon the periphery of a .boss of the cam 3|; the free end of the arm being curved to fit about said periphery. The curved end of the arm 94 is wedge or knife-shaped and i; adapted to engage a pin or key 98 slidably mounted within the boss 91. A spring (not shown) normally urges the key 98 outwardly of said boss and into a recess provided in a sprocket 91a secured to the gear 21 by which gear the cam shaft is driven by the gear 28. When the wedge-shaped outer end of the curved arm 94 is in its lowermost position as shown in Fig. 8, it engages within a slot or groove of the'key 96 to cause the key to be moved out of engagement with the sprocket thereby uncoupling the clutch. The placing of the clutch in operative condition is brought about by depressing pedal lever 93. Said lever 93. has

connected to its inner end, the lower end of a connecting rod 98, the upper end of which has secured thereto a laterally projecting block 99 adapted to engage a cooperating block I09 which projects laterally from theside of the arm 94. A spring llll has one end thereof anchored to the framework of the machine and the other end to hold the rod 98 in its lowermost position, in I which position, the knife-edge of the arm 94 is in engagement with the key 96.

In order to prevent the continuous operation of the machine even though the operator may hold the pedal 93 depressed, and to insure that the one revolution clutch will function to stop the rotation of the camshaft upon completion of the full cycle of operating of the labeling devices, the rod 98 is supported for transverse swinging movement upon a link I02 one end of which is pivotally connected to said rod and the other end of which is pivotally mounted in a laterally projecting boss I03 of the bracket II. A cam IE4 is secured to the cam shaft 26 for engagement with a roller I05 projecting laterally from the rod 98 above the point of the pivotal connection therewith of the link I02; the throw of the cam I04 engaging the roller I05 and moving the rod 98 so that the block 99 on said rod will be moved out of alignment with the block I00, thereby insuring that the knife-edge of the arm 54 will be in position to cause the disengagement of the clutch when the cam shaft completes its full revolution.

Operation of the knife clutch will be readily understood, depression of the pedal 93 by the operator causing the member 94 to be raised out of contact with the sliding key 96 and allowing the key to be-forced by the action of its spring into the recess of; the sprocket 91'a' thereby tolock cam 3|, which is secured to the cam shaft-26, and the sprocket 91-h together and to'cause the cam shaft 26 to be rotated. Asthe cam shaft completes its revolution, the wedge-shaped end of the arm 94' engages the key and forces it against the action of this spring to causethe clutch to be disen ter may be otherwise located within the drum 7 I01 or in external operative relation thereto.

' Guides I08, I09, are provided for .the webs'a and b,

respectively, said guides being suitably supported from the standard 0- in which the shaft I II of the drum I01 is mounted. In order to insure that the adhesive coatings of the paper webs will be properly activated by the drum I01, i. e., for the time durations required or deemed most dosirable in any given case, the following mechanism is provided: Pivotaliy mounted for adjustment upon a lateral extension of thestandard H0 is a roller supporting arm II2, carrying at its outer end a roller II3. By shifting the roller II3 into any selected position between the full-line and dotted positions shown, the webs, are retained in engagement with the heating surface for varying periods of time. The arm I I2 may be held in the selected adjusted position by any suitable clamping means (not shown). A follower roll H4 is mounted at the free end of an arm II5, the other end of which is pivotally supported upon a stud or pin H6. The drum I01 is driven by the following means: The sprocket 91-a, see

Fig. 1, with which the key 96 of the knife-edge.

pulley I20 and a pulley secured to a shaft I 21' (Fig.6) journalled in the standard I0, is a belt 122, which causes the shaft I'2I to-be driven from the! associated mechanism illustrated in-Fig 'fi.

' above which is a pulley- I24, secured to the drum Secured to the shaft .I2I isa' second pulley I23 shaft s. About these pulleys ifs-trained a belt gaged. If the operator holds the pedal 93 depressed until after the cam shaft has completed its revolution, the operation of thecam I04will insure the stopping of the cam shaftat the end of the machines cycle, and, in order to cause the machine again to become operative, it will be necessary for the operator to release the pedal and then depress it again before the clutch can be coupled.

PAPER SUPPLYING,ACTIVATING, AND

TENSIONING MEANS-B The paper web may be fed to the machine as a single strip of printed paper or if it is desired to give the article a distinctive appearance, two strips of paper of different colors or printings may be provided, one of which slightly overlaps I25 for driving the drum from the aforesaid associated mechanism. :As the paper 'passes from-the activating drum I01 to the intermittent feeding device,-it is trained over guides us and 121 which are of similar construction and consist of a laterally-extending arm suitably supported from the framework.' Each arm is preferably provided with a ball-shaped end I40 clamped between a pair of recessed plates "I4I, said platesbeing clamped in engagement with'the end I40 by a bolt I 42. The ball-shaped end of each arm cooperates with the recessed plates to permit universal adthe other, or one of which may be a narrow strip laid on as a stripe. In Fig. 6, I have shown the machine as being provided with two strips or webs of paper, a. b, which strips are led from rolls supported in the reels I05, I06, respectively, and over a paper feeding and activating drum I01, of relatively large diameter.- Suitable activating means is operatively located relatively to the activating drum I01 either externally or internally th reof or in both external and internal relation thereto as may be pre erred, said activating means being diagrammatically illustrated'in the form of heat developing means. In the example shown in Fig. 6. the heat developing means is shown at l01-a within the drum I01 anri'is in-' dicated as an electrically-operated device 10- l justment of the arms I26, I21. By inclining such arms as required, the paper can be made to track true, and so that sidewise creeping thereof can readily be prevented. It will be understood that the arms I 26, I21, are oppositely arranged, that is with the ball end of the arm I26 located adjacent to one side of the frame while the ball end of the arm I21 is at the other side of the frame.

INTERMITTENT FEEDING DEVICE-C In its passage from the activating station to the labeling mechanism the web is engaged and fed to the labeling mechanism as required by an intermittent feeding device, which may be of any suitable construction, but which as shown, comprises the following parts: Adjustabiy mounted upon a sub-frame I28, extending latera ly from the main frame I0 is a table I29, any suitable adjusting devices, such as the screws I30, connected for simultaneous movement by the sprocket chain I 3I being provided for moving the table vertically. Mounted on a suitable guide I32, provided upon the table I29, is a slide I33, carrying a paper gripping member I 34, mounted for limited oscillation upon said slide by means of a rocking arm I35. The rocking arm I35 is connected by a rod I36 with an oscillating lever I 31 pivotally mounted at its lower end as at I38. One end of an actuating rod I39 is connected to the oscillating lever between the ends of said lever, the otherend of said rod being supported in any suitable manner, and being provided with a roller which engages with a cam I40, secured to the camshaft 26, which cam is provided with a camrace of suitable contour for causing the paper gripping member I34 to be oscillated and the slide I33 to be reciprocated in properly timed relationship with the manipulation-of the core I9 to feed the paper to said core. I I

STRIP SEVERING DEVICEQ-D the table I29. The other end of the two armed lever has connected therewith one end of a connecting rod I46, the other end of which rod is connected with one end of a bell "crank lever I41, the other end of which carries a cam roller I48, held in contacting engagement, by any suitable means, with the periphery of a cam I49, secured to the cam shaft 25.

OPERATION It will be understood that before a job'is started upon the machine, a core I9 of the proper size and shape is secured to the hollow tubular shaft I8, and other adjustable parts of the labeling machine will be adjusted in accordance with the size and shape of the article to be labeled. At the beginning of a cycle of operations of the machine the several heating or other activating devices are in operation, and the core I9 is in the position indicated by the full lines in Fig. 1. The operator positioned in front of the machine will place an article upon the core I9. The pedal lever 93 is now depressedby the operator, thus causing the one revolution clutch to become operative to rotate the cam shaft 26. As the cam shaft 26 begins its rotation, the cam 42'moves out of engagement with the cam roller 43, thus permitting the shaft or rod 20 to be moved rearwardly relative to the tubular shaft I9 by the spring 45. When this occurs, the cams 55 (Fig. 2), are moved rearwardly and the rollers 54 ride down off the cams 55, thus permitting the yoked levers 53 and the finger carrying arms 59 to moveinwardly and bring the fingers GI] into engagement with the article upon the core I9 and to hold said article securely in position upon said core. Immediately after the fingers 60 grip the article, the rotation of the cam shaft 26 causes the tubular shaft I8 to be withdrawn by the ac-- tion of the cam ill and associated parts to bring the core rearwardly to the dotted line position shown in Fig. 1, in which position the core is in alignment with the roller 62. The web feeding mechanism now thrusts the end of an activated label between the roller 62 and the article upon the core I9, the roller 62 at this time being held,

10 wise direction, thus moving the roller upwardly and holding the activated side of the label against the article. Just as this occurs, the intermittent gearing 24, 25, becomes operative to rotate the tubular shaft. .Upon the completion of a full revolution of said shaft, the pawl 8| becomes active to cause'the roller 62 to be moved to its lower inoperative position, and the cam 3| becomes operative to movethe core I9 forwardly. Just as the core I9 reaches the extreme forward position, the cam 42 becomes operative to hold the rod 20 against the action of the spring 45 and thereby cause the ejector plate 2I to remain stationary as the core I9 is retracted, thereby stripping the labeled article off the core. After the article is removed from thecore and the tubular shaft and core are retracted, the cam roll 43 follows the inclined portion of the cam face 42 and comes to rest in the starting position indicated in Figs. 1 and 2 of the drawings. The complete cycle of the machine's operation is now completed and the one-revolution clutch opcrates automatically to stop the rotation of the by the pawl 8|, against the action of the spring I8, in its lowered position. The pawl 8| and ratchet 80 is nowreleased by the cam yoke 92,

cam shaft. All of the parts are at rest in the starting position and will remain at rest until th clutch pedal 93 is again depressed.

It will be understood that as the coated paper travels over the activating roll II", the adhesive coating thereof will be subjected to the heating influence of the activating device Ifll-a and, accordingly, will be transformed from a non-adhesive condition to. an adhesive state. As the paper continues to travel from the activating roll to the point of application in the machine, the activated coating will become properly tacky and brought to a condition of maximum adhesiveness. In other words, the timeperiod which elapses between the activation of the adhesive coating and the application of the paper may be termed a storage period during which said coating develops its adhesiveness to a maximum degree.

While the embodiment of the invention herein disclosed is a satisfactory constructional example thereof, it will be understood that the principles of the invention are not limited to the specific constructional details illustrated but that many changes, variations, arid modifications may be made without departing from the spirit of the invention.

I claim:

1. In a machine of the kind described, the combination of means for supporting a continu ous strip in roll form, said strip being coated on one surface with a thermo-activatable' adhesive material, heating means, feeding means for conveying said strip from said roll past said heating means, said feeding means including a rotatable cylindrical drum whose peripheral stripsupporting surface is heated by said heating means, and adjustable means coacting with said feeding means for varying the length of the strip section which is in contact with said drum surporting surface is heated by said heating means,

and means coacting with said feeding means for varying the length of the strip section which is in contact with said drum surface at a given against said strip.

11 moment, said last-named means comprising a roller mounted for adjustment toward and away from said drum surface and adapted to bear 1 3. In a machine of the kind described; the combination of means for mounting a continuous strip in roll form, said strip being coated with a thermoactivatable. adhesive, heating means for progressively activating said adhesive as the strip is fed from said roll, means for feeding. the. activated portion of said strip to a point of use spaced from said heating means, and severing means be-' tween said heating means and'said 'point of use adapted to cut off an activated section of said strip. I

4. In a .machine of the kind described, the combination of means for mounting a. continuous strip in roll form, said strip being coated with a, thermo-activatable adhesive, means for conveying said strip from said roll to a remote point of use including a convex arcuate strip-supporting surface with which the stripis in contact during part of its travel from said roll to said point of use, means associated with said arcuate surface for heating and thereby activating said strip in a progressive fashionwhile it'is in contact with said arcuate surface, and severing means adjacent to the-point of use for cutting off an activated end section of said strip.

5. The method of attaching adhesively coated sheet material to articles, comprising the steps support, pressing the strip against the support during its passage thereover and at the same 'of continuously feeding a strip of thermo-activatable adhesive coated sheet material over aing thereon, storing the activated portion of the strip in a region intermediate its place of activation and a place of use, and then applying an advanced end of the activated strip to an article.

6. In a machine of the kind described, the combination of means for separately supporting at least two strips each of which is in roll form and is coated on one surface with a thermo-activatable adhesive, means for conveying said strips from said rolls into an overlapping relation in whichat least one longitudinal edge of one strip is offset from a longitudinal edge of the other while the coated surfaces face in the same direchesively activated coating by which said composite strip may be secured to an article.

7. In a machine of the kind described, the combination of means for separately supporting at least two strips each of which is in roll form and is coated on one surface with a thermo-activatable adhesive, means for conveying said strips from said rolls into an overlapping relation in which said coated surfaces face in the same direction, one of said strips being narrower than the other whereby at least one longitudinal edge of one strip is offset from a longitudinal edge of the other, and heating means for progressively activating both of said coatings on said overlapping strips to effect the union of said strips and to provide a composite strip having an exposed adhesively activated coating by which said composite strip may be secured to an article.

8. In a mechanism for supplying adhesively coated sheet material to be aflixed to articles, a supply in the form of a continuous strip coated with a, thermo-activatable adhesive, a rotatable means having an endless strip-supporting surface for conveying said strip toward a point of discharge, and stationary heating means located within the area defined by said surface and adapted to supply sufficient heat through said surface to activate the coating on the strip section which is in engagement with said surface.

9. Ina mechanism for supplying adhesively coated sheet material to be affixed to articles, a supply of sheet material coated with a thermoactivatable adhesive, means having a sheetsupporting surface for conveying said sheet material toward a point of discharge, heating means associated with said surface for activating the coating on the sheet material during the engagement thereof with said surface, and tension means engaging said sheet material and maintaining the latter under tension while in contact with said surface.

10. In a machine for activating a continuous strip coated with thermo-activatable adhesive, a cylindrical heating means, and means for rotating said cylindrical means about its axis for tensioning and bending said strip around said heating means with the uncoated side of said strip against the heating means to maintain each successive portion of said strip in contact with said heating means for a predetermined interval.

11. In a machine for activating a continuous strip coated with thermo-activatable adhesive, means having a heated surface, and means for tensioning said strip with the uncoated side of said strip against the heated surface, said tensioning means maintaining successive portions of said strip passing over said surface in contact with the latter for a predetermined interval.

12. The method of attaching thermo-activatable adhesive coated sheet material to articles, comprising the steps of pressing such material against a support and at the same time applying heat thereto to activate the coating thereon, storing the material to allow the sheet and its activated coating to cool below the activating temperature and to allow the coating to develop an enhanced tackiness, and then applying the activated material to an article.

13. The method of attaching thermo-activatable adhesive coated sheet material to articles, comprising the steps of advancing such material under tension past heating means capable of subjecting the adhesive coating thereon to an activating temperature substantially above room temperature so that successive portions of said coating will be activated in a progressive fashion, then storing the sheet material for a suflicient period to enable its temperature to drop substantially below said activating temperature, and then applying the adhesively activated cooled material to an article.

14. The method of preparing for use a web of thin flexible material coated on one side thereof with an inactive but thermally activatable adhesive coating, which comprises the steps of progressively heating successive areas of said material and the coating thereon to an activating temperature sufficiently high to transform said coating from an inactive state to a state of adhesiveness, and then before using the activated material allowing it and the activated adhesive coating thereon to cool to a temperature appreciably below said activating temperature.

15. The method of adhesively attaching sheet material to articles, com rising the steps of feed- 13 ing a strip of thermo-activatable adhesive coated sheet material past a heating station to activate successive areas of the strip, storing the activated material for an appreciable time period to allow it to cool and to achieve an enhanced substantial tackiness, and only then applying the activated material to an article.

GEORGE W. VON HOF'E.

REFERENCES CITED The following references are of record in the file of this patent:'

Number 14 UNITED STATES PATENTS Name Date Jean Oct. 15, 1918 Edwards Aug. 7, 1934 Malocsay Dec. 28, 1937 Schuneman Jan. 31, 1939 Wescott Dec. 10, 1940

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