US2506303A - Apparatus for applying labels to spools - Google Patents

Description

May 2, 1950 R. B. LANGE APPARATUS FOR APPLYING LABELS TO SPOOLS 4 Sheets-Sheet 1 Filed Jan. 14, 1949 FIG.I

INVENTOR fzaZ/arzafllanye BY ATTO R N EYS R. B. LANGE APPARATUS FOR APPLYING LABELS TO SPOOLS May 2, 1950 Filed Jan; 14, 1949 4 Sheets-Sheet 2 FIG. 2

FIG. 7

FIG. 8

INVENTOR fial/armfi Lap 0e ATTORNEYS May 2, 1950 R. B. LANGE APPARATUS FOR APPLYING LABELS T0 SPOOLS 4 Sheets-Sheet 5 Filed Jan. 14, 1949 'INVENTOR Fallen/, Zar/ye BY PM Elm... ad. $15M,

FIG. 3

ATTORNEYS y 2, 1950 R. B. LANGE 2,506,303

APPARATUS FOR APPLYING LABELS TO SPOOLS Filed Jan. 14, 1949 v 4 Sheets-Sheet 4 FIG. 5

INVENTOR Holland ,3 1077]? BY PM l -WA KWM ATTORNEYS Patented May 2, 1950 APPARATUS FOR APPLYING LABELS T SPOOLS Rolland B. Lange, Muskegon, Mich., assignor to Anaconda Wire and Cable Company, a corporation of Delaware Application January 14, 1949, Serial No. 70,988

9 Claims.

This invention provides improved apparatus for applying a label to the periphery of a spool, and especially for commercially applying labels to spools which may vary considerably in diameter in the region where the label is applied. The apparatus is especially suited for wrapping protective labels peripherally about spools of fine magnet wire. The label, of course, serves the additional purpose of carrying markings showing the size and nature of the wire, the name of the manufacturer, etc.

When magnet wire is packaged on spools, it is desirable to apply a paper label to the periphery of the spool so as to cover up and protect the wire from damage. Many ingenious machines have .been devised for applying labels peripherally to spools and other cylindrical objects, but the machines heretofore used successfully for this purpose have :been designed to operate on spools or containers of uniform diameter. No thoroughly satisfactory machine for applying labels to magnet wire packaged on spools has heretofore been devised, because in the magnet wire industry the amount of wire on a spool may vary over quite wide limits, and consequently the diameter of the package of wire on the spool is quite variable. The label should be pulled up tightly about the wire onthe spool in order to afford maximum protection, so the label-applying machine must be of such nature as to wrap the label tightly regardless of the diameter of the spool package to which it is applied.

The label-applying machine of the invention meets the foregoing requirements. The principal features of the new machine are the label guide by which the label is guided into position peripherally about the spool, and the mechanism by which the label then is wrapped about the spool. The label guide of the new apparatus has a substantially cylindrical section and a substantially plane section extending tangentially therefrom, with a narrow opening at the juncture of the cylindrical and plane'sections for insertion of a label into the interior of the cylindrical section. The cylindrical section further is formed with at least two'slots of length somewhat less than the width of a label, and of considerable width (the angular width of the slots may well be 90 or more, measured from the axis of the cylinder). The slots are substantially centrally positioned along the length of the cylinder so as to leave a pair of substantially full cylindrical guide shoes, which are spaced from each other on a common axis, at each end of the cylinder. The label guide 2 single sheet of metal or other material, or it may be built up from several separately formed components defining the plane section and the cylindrical guide shoes.

The inside diameter of the cylindrical section v of the label guide is only slightly larger than the diameter of the flanges of the spool, and provision is made for introducing a spool to be labeled axially into the interior thereof. The plane section of the label guide serves to guide a label into contact with the inner surfaces of the guide shoes, and these in turn serve to guide the label into cylindrical form about the periphery of a spool to be labeled, the outer surface of the label being exposed through the slots so that a rotative force may be applied to it for wrapping it about the spool.

The mechanism by which the label thus guided into position about the spool is wrapped in place thereon comprises a pair of endless belts each rotatably mounted on rollers whose axes are parallel to the common axis of the guide shoes. The belts are positioned so as to face the slots in the cylindrical section of the label guide, and are mounted so that they may be swung, in a plane perpendicular to the axis of the guide shoes, broadside through the slots into and away from frictional engagement with the periphery of a spool positioned inside the guide shoes. When the belts are rotated and pressed against the spool, they serve to wrap a label, guided into position by the label guide, about the periphery of the spool within the guide shoes. At the same time, of course, they serve to rotate the spool about its axis. If the belts are held in engagement with the label on the spool for the length of time required for the spool to make several complete revolutions, the label is drawn up snugly against the wire packaged thereon, regardless of the diameter of such package; and if a suitable adhesive has been applied to the label, it is held thereby in position about the spool even after the belts are released by swinging them away from the spool. Then the labeled spool may be removed axially from within the label guide, and a new spool may be introduced.

A machine in which the improved label guide and label-wrapping mechanism of the invention are incorporated is described in greater detail below in conjunction with the accompanying drawings, in which:

Fig. 1 is side view, partially in section, of the machine of the invention;

Fig. 2 is a plan of the machine shown in Fig. 1;

Fig. 3 is a horizontal section taken substanalong the line 6-6 of Fig. 3, showing a spool in position to have a label applied;

Fig. 7 is an isometric view of the label guide;

Fig. 8 is a plan of a label showing a preferred location of the application'of adhesive thereto; and

Fig. 9 is a view of a labeled spool of wire.

Referring to Fig. l, the machine stands on a base Ill and comprises a spool feeding deck if supported above the base, along which each spool I2 is fed into position to have a label applied. A label guide and label-wrapping mechanism I3 is mounted above the spool feeding deck on the underside of a supporting frame hi, and above this frame is a table carrying the motor drive for the apparatus.

The label guide it is shown separately from the machine as a wholein Fig. '7, and its position inthe machine is apparent from Figs. 1, 4, 5 and 6.- It comprises a plane section ['1 tangentially connected to a cylindrical section l8. It is conveniently formed by bending one end [9 of a sheet-of smooth metal or other suitable material around in the form of a cylinder, leaving unbent the portion of the-sheet that is to form the plane section l'i. The inside diameter of the cylindrical section is just a little greater than the diameter of the end flanges of the spool E2. The bent end [9 of the cylindrical section is not quite closed against the plane s'ection H, but instead a narrow aperture '20 'is left between them. The cylindrical section I8 is formed with two wide slots '21 diametrically opposite each other (the angular 'widthof "these slots is indicated by the angle A in Figs. 4 and 7 and advantageously exceeds 90). The slots are'of a' length, measured along the length of the cylindrical section 18, that issomewhat less than'the width of a label, and they are approximately centered along the length of the cylinder so as'to leave two substantially full cylindrical guide shoes 22; which are spaced from each other along a common axis, at the ends of the cylindrical section.

The plane section l'lof the labelguide serves to guide a label through the aperture into contact with the inner surface of the cylindrical section is, and this latter section serves to guide,

the label into cylindrical form about the periphcry of the spool to which it is to be applied. To facilitatethis guiding action, the plane and cylindrical sections of the label guide both are provided at the top and at the bottom with guide rails 23 to insure that the label will be delivered into the cylindrical section in centered relation between the ends thereof; Additionally, the plane section I! is provided with guide ways 24 to prevent the label from falling out once it has been inserted. The rails ,23 are spaced apart a distance just a little greater than the width of a label, and the guide ways 24 are spaced by these rails from the bodyjof the plane section H by a distance enough greater than the thickness of the label '50 that the label may be slid; easily along theplane section behind the guideways into en- 4 gagement with the inner surf-aces of the cylindrical guide shoes 22.

From the foregoing it is apparent that a spool must be positioned Within the cylindrical section it of the label guide so that a label guided thereby into cylindrical form may be wrapped about the periphery of the spool. This is accomplished by providing for introduction ofone spool at a time axially into the interior of this cylindrical section. The mechanism for doing so is best shown in Figs. 1 and 6. The spool 12 to be labeled is delivered along the deck H to the position where its hollow barrel is approximately centeredover a vertically movable turntable Z5.

-- The turntable is. carried on the upper end of a vertical shaft 23 supported in bearings 2'? and 28. The label guide is secured to the supporting frame [4 in such positionthat the axis of its cylindrical section It coincides with a projection of the axis of the turntable 25. A lever 29 pivctally connected to a fixed support 30 and to the shaft 26 provides for lifting the turntable from a position just below the spool feed deck I! (as shown full'lines in Fig. 1)' to an elevated position where when it just enters the lower guide shoe of the cylindrical section of the label guide (as shown in dotted linesin Fig. 1 and in full lines inFig. 6) A latch 35 is provided to hold the shaft 26 in it elevated position.

The turntable 25 is formed with an upwardly projecting centering pin 32 so that when a spool I2 is moved along the feed deck H to a position approximately centered over the turntable and the lever 29 is then raised, the spool, is automatically centered on the turntable and is lifted axially intoposition. within the cylindri al sec: tion of the label guide. The spool'is held from tilting when in its elevated position by a pilot pin 33 secured to the supporting frame M on the axis of the cylindrical section of the label guide. In its elevated position, the spool is free to rotate about its axis on the turntable.

The mechanism by which a label delivered through the label guide, is wrapped about the periphery ofa spool supported by the turntable 25'centrally within the cylindrlcalasection of the label guide is best shown in Figs. 3 to 6. It co m-. prises a pair of softendless belts, 35 (advantageously, of rubber). eachv of which iscarried on a pair of rollers 36 and 31.. Each pair of rollers is supported between upper and lower members 38 of a roller frame with their axes parallel to the axis of the cylindrical section l8 of the label guide. The roller frame members 38 are pivotally mounted on shafts 3.9, and 240, which shafts are supported at' .their'upper ends bythe supporting frame Hand are steadied at their lower ends by frame elements 4 fdepending from the supporting frame M. (The frame elements further serve to hold the label guide securelyin position.) The shafts'39 and 4B are secured axially to the rollers 35, which are the driving rollers for the belts 35. The other rollers 31 are idling rollers for holding the belts taut and in position.

The position in whicheach roller frameis supported on its pivot shaft 359 is such that the broad face of each belt 35, midway between the rollers, lies directly; opposite the wide openings 2i in the cylindrical section I8. of the label guide. The belts are a trifle narrower'than the length of the slots 2!, and therefore the belts may be swung broadside through these slots, into and away from frictional engagement :with the periphery of a 'spool'positioned inside the cylindrical section of the labeiguide. by movem nt of the. roller frame members 38 about their pivot on the shafts 39 and 40. Fig. 4 shows the belts swung out and away from engagement with a spool inside the cylindrical section of the label guide, and Fig. 5 shows them swung in through the slots and in engagement with the spool.

A lever system is provided for swinging the roller frame members 38 simultaneously toward or away from engagement with a spool in position to receive a label. This lever system, best shown in Figs. 2 and 3, comprises a main control lever 42 pivotally mounted for movement through a small angle about the axis of the cylindrical section of the label guide. It is conveniently pivoted on an upward projection 43 of the pilot pin 33 (Fig. 6). An extension of this lever projecting beyond the supporting frame l4 provides a handle 44 for manipulatin it. Two links 45 are pivotally connected to the lever 42, on opposite sides of and equidistant from the axis about which the lever 42 moves. Each of these links is pivotally connected at the end remote from the lever 42 to the center portion of one of a. pair of motion multiplying levers 46. One end of each of these latter levers is connected to a fixed pivot 47 on the frame of the machine, and the other end of each is pivotally connected (through a vertical arm 48', shown in Fig. 1) to the end of one of a second pair of links 48. The other ends of the latter links 48 are pivotally connected to a spreader bar 38' (Fig. 1) joining the upper and lower roller frame members 38. This lever system is such that when the handle 44 of the main lever 42 is swung to the left (the position shown in full lines in Fig. 3), the roller frames are swung about their pivotal mountings on the shafts 39 and 40 away from a spool inside the cylindrical section [8 of the label guide, and the belts 35 are thereby disengaged from frictional engagement with the periphery of the spool (the belts then are'in the position shown in Fig. 4). When the handle 44 is swung to the right (the position indicated by the dotted lines in Fig. 3), the roller frames are swung in toward a spool positioned axially within the cylindrical section [8 of the label guide, and the belts 35 are moved broadside through the slots 2! into frictional engagement with the periphery of the spool (taking the position shown in Fig. 5)

If, when the belts are swung into frictional engagement with a spool in position for receiving a label, they are rotated on their rollers 36 and 31, and if at the same time a label is fed in through the plane section I! of the label guide, it is apparent that the belts will rotate the spool and wrap the label therearound. A motor drive (best shown in Figs. 1 and 2) is provided for rotating the belts. This drive comprises a motor 50 bolted to the motor table I 5 and driving a bevel gear 5i through a speed reducer 52. The bevel gear 5i on the output shaft from the speed reducer meshes with a corresponding bevel gear 53 mounted on the end of the shaft 40 to which one of the beltdriving rollers 36 is secured. Also mounted on this shaft is a sprocket wheel 54 connected by a sprocket chain 55 to a second similar sprocket wheel 56 secured to the shaft 39 on which the other driving roller is mounted. When the motor is energized, both shafts 39 and 40 are rotated thereby at the same speed, and in consequence the two belts are rotated at the same linear speed on their supporting rollers. The drive serves to rotate both belts in such direction that they cooperate to rotate a spool with which they are in 6 frictional engagement through the slots 2| in the cylindrical section of the label guide.

Sometimes it is advantageous to have the belts not rotating while they are swung into frictional engagement with a label to be applied to a spool,

and to set them in motion only after such frictional engagement has been made. This is accomplished by providing in the motor circuit a switch 51 (Fig. 1) that is normally opened but that is closed when a plunger 59 is depressed. The lever handle 44 by which the rollers are swung into engagement with the periphery of the spool to be labeled is provided with a leaf spring cam 55 which closes the switch 51 when the lever has been thrown over to the position in which the belts engage the spool. Thus the motor is started after the belts engage with the spool and is stopped again when the belts are disengaged from the spool.

Operation of the apparatus is as follows: A spool I2 to be labeled is slid along the deck H into the position shown in full lines in Fig. 1, where its barrel overlies the turntable 25. The lever 29 is then raised to the position shown in dotted lines in Fig. 1, thereby lifting the spool axially into the interior of the cylindrical section i8 of the label guide. A label of width about equal to the length of the spool and of sufiicient length so that its ends overlap when wrapped around the periphery of the spool is inserted into the plane section ll of the label guide, its edges being supported by the guide ways 24. The label is inserted in such manner that the face carrying the printed data is toward the body of the label guide, and two or more spots 6| of an adhesive are applied on its back surface near its tail end (the end last entering the label guide). Suitable locations for the two spots of adhesive on the back surface of a label 52 are shown in Fig. 8. The adhesive should, of course, be applied far enough in from the side edges of the label so that it does not smear on the guide ways 24, and it is advantageous to apply it far enough in from the tail end 53 of the label so that after the label has been wrapped around the spool the tail end will serve as a tab by which the label can readily be removed.

It is only necessary that the label be inserted far enough into the label guide so that its entering end 64 passes about to the midpoint of the first opening 21 in the cylindrical section l8, although it may be inserted as much farther as desired. Next, the lever 44 is swung in the proper direction (to the right, as shown in Fig. 3) and to the extent necessary to cause the belts 35 to press against the outer surface of the label (or the periphery of the spool) where it is exposed through the openings 2!. At the same time, the switch 5'! is closed and the motor is thereby energized to rotate the belts in the direction indicated by the dotted arrows in Fig. 3. The frictional engagement of the belts with the label causes it to be wrapped about the periphery of the spool, the spool being rotated at the same time. By holding the belts in this label-applying position long enough for the spool to make several complete revolutions, the label is drawn up tightly about the wire or other material packaged on the spool, regardless of the amount of wire on the spool and hence the effective diameter of the package. The adhesive used should, of course, be one which sets quickly (a smooth flour paste is one adhesive that has been used successfully), so

that when the lever 44 is returned to its original position, disengaging the belts from the spool, the label is held tightly in placeabout the periphery oil the spool; Next: the lever 2& is. re;- leased, loweringv the. now labeled spooleaxially; fromfwithin the. cylindrical section: of. the; label guide. It is removed from; the deck M, a new spool to'be labeled is brought into. position over 5,

the turntable. 25., and the. sequence of operationis repeated.

The form of machine herein. shown is. designed for manual operation of'the levers29'and 44, manual insertion and Withdrawal of the spools, and manual insertion of the label into the plane section l'l o f the label guide. However, attachmentsmay be made to the machine for automatically feeding the spools and the labels, and for automatically operating the levers 29 and itin proper sequence. Mechanism for such automatic-operation forms no part of the present invention, which is directed especially to the means by which the label is guided into position about the spool and is wrapped tightly thereon regardless of" the diameter of the package of wire or other material on the spool.

Fig. 9 shows a spool as it appears after having been labeled by means of the apparatus of the invention. The label 6?. is drawn tightly about the periphery of the package ofwire on the spool, between the spool flanges 65, and is held in such position by the spots of; adhesive 6|. The tail end, 66". of. the label where it projects slightly beyond; the spotsoi; adhesive forms a convenient tab for stripping thelabel from the spool when the material thereon is to be exposed for use. Until such time the. label efiectively protects the line enamelledwire Or other easily injured produet packaged on the spool fromv mechanical inj ry.

' I claim:

l. Apparatus for applying. a label to the periphery or a spool. cumprising. a label. guide-haying a pair. of cylindrical guide shoes spaced apart. on a common axis andv each having. an inside diam ter only slightly greater thanv the diam eter of the spool flanges,- said guide shoes being. spaced apart a distance, somewhat, less than the. width of a label and being formed with an open-m ing through which a label may be inserted intocontact with the-inside faces, thereof, means for introducing a spool; axially into the interior of said guide shoes, and a pair of softrendlessrbelts of width. less than theaxial. spacing between the;- guide shoes each mounted, on a pair. of spaced; rollers having axes. parallel to. the axis of the guide shoes, the belts between the, supporting; rollers being movable laterally in. a plane.- perrpendicular to the axis of theirollers in the space between theguide shoes into andaway from engagement with the periphery of. a spool: posi-. tioned inside the-guide shoes, whereby the beltsma-y bebrc-ught into contact with a label inserted. into the guide shoes for Wrapping said labelr tightly about a spool positioned axiallywithin. saidshoes.

2. Apparatus for applying a label to the pe-. ripher of. a spool comprisinga cylindrical label; guide of inside diameter only sliehtly'larger than. the diameter of thespool flanges and: of length:- apprc-ximately equal to the length of the spool; said cylindrical guide having a pair of wide sub stantially. diametrically opposed slots oflength somewhat less than the width of the label; the slots bein approximately centrally disposed along the length of the cylinder-so as to leave apairof substantially full cylindrical guide shoes at the ends thereof; and said cylindrical guide;

iurtherbeingiormed with-an-openlngfor intro 1' duci-ng a; label tangentially into;v the. interiorthereof, meansfor introducing. a spool to be 1a? beled axially into. said cylindrical'guide, and a.

pair of soft endless-belts each mounted and rotatable on a. pair ofi -rollershaving. axes parallel to the axis of the cylindricalgnide, saidbelts;

being of a width somewhat less than the length of-rthe aforesaid-slotsand being movable broad.- side in a planepe-rpendicular to: the axis of the cylindrical guide through the slots into, andaway from engagement with the: periphery: oi a spool positioned inside said; guide wherebythe belts may, be. brought, intOJ' contact with a. label in serted tangentially. into the; cylindrical guide forwrapping; said label; tightly about the periph-- tially at one end of said plane-section, said guide:

shoes adjoining; theplane. section, at its sides. and beingspaced apart, on av common; axis by a distance somewhat less than the: Width. of a label, the label guide being; formed; with an aperture at the juncture of the plane; section with the-- guide-shoes through which a label may be passed from the plane section tangentially into contact with the inside surfaces of the guide shoes, means for introducing a spool. to belabeled. axially into the guide. shoes, and apair of soft endless belts rotatable on rollersv whose axes are parallel to the axis of the. guide shoes. and; movable in a plane perpendicular to-the axisofthe guide shoes in; the spacev between. said shoes broadside into:

and. away from frictional. engagement with the periphery of a Spool, positioned within the guide shoes, whereby said belts may be brought into contact. with a label inserted into. the interior of. the guilde. shoes for wrapping said label tightly about the periphery of a spool positioned therein.

4. In apparatus for applying alabel' to the periphery of a spool, a label. guide having a substantially cylindrical, section and a substantially plane section extending substantially tangentially therefrom. said guide having an opening which theperiphery-of a spool positioned insidesaid: cylindrical: section is exposed; and at least two; endless. belts of'soft material of width less than the length. of: sald slots mounted and rotatable on. rollers whose axes are parallel to the axis. of said.- cylindrical; section, said belts being each: movable laterally ina plane perpendicular tothe; axis of thescylindrical;section through one of -said slots; into. and; away. from. frictional engagenient; with. tlieiperipheryiof; a: spoolsupported axially: within; said cylindrical section, whereby said belts maybe breughtrintd contact: with a.

label. inserted into the: cylindrical: section of the label guide for wrapping said-ilabel, tightly about the peripheryofya spool positionedtherein.

5. A label guide for guidinga label into positionto, be, wrapped ab out. the periphery.- ofa spool comprising a, substantially planesection and a pair of. cylindrical, guide shoesv connected substan tially, tangentially. to theplane sectionat one end thereof adjacent its side edges, .said, guide.- shoes,

beingsnacedflapam one commonaxis by a distance somewhat less than the width of a label and each having an inside diameter only slightly greater than the diameter of the spool flanges, said label guide having a narrow aperture where the plane section adjoins the guide shoes and through which a label may be guided by the plane section into contact with the inner surfaces of the guide shoes.

6. A label guide for guiding a label into position to be wrapped about the periphery of a spool comprising a smooth metallic sheet bent to form a cylindrical section from which a plane section extends tangentially, the cylindrical section having an inside diameter only slightly larger than the diameter of the spool flanges and being not quite completely closed against the plane section, whereby a narrow aperture is provided through which a label may be guided by the plane section into contact with the inner surface of the cylindrical section, the cylindrical section being formed with a pair of Wide slots of length somewhat less than the width of a label located midway between the ends of said cylindrical section, whereby the face of a label in said cylindrical section is exposed through said slots for the application thereto of a rotative force for wrapping it about the periphery of a spool positioned within said cylindrical section.

7. In apparatus for applying a label to the periphery of a spool, a cylindrical guide for guiding a label into cylindrical form about a spool in position to be labeled, and means for wrapping the label tightly against the periphery of such spool comprising a pair of endless belts each mounted on a pair of rollers whose axes are parallel to the axis of the spool, each pair of rollers being supported in a frame which is pivotally mounted to swing in a plane perpendicular to the axis of the spool, said frames being disposed on opposite sides of the spool, a lever system for swinging the frames on said pivotal mounting toward and away from the spool, whereby the faces of the belts may be frictionally engaged with and disengaged from a label in position to be applied about the periphery of the spool, and motive means for rotating the belts on the rollers while the belts are in frictional engagement with a label on the spool.

8. In apparatus for applying a label to the periphery of a spool, a cylindrical guide for guiding a. label into cylindrical form about a spool in position to be labeled, and means for wrapping the label tightly against the periphery of such spool comprising a pair of endless belts each mounted on a pair of rollers Whose axes are parallel to the axis of the spool, a roller frame supportin each pair of rollers and holding them spaced apart sufficiently to keep the belt taut, each roller frame being pivoted on the axis of one of the rollers to swin in a plane perpendicular to the axis of the spool, said frames being disposed on opposite sides of the spool, a lever system for swinging the frames on their pivots toward and away from the spool, whereby the faces of the belts may be frictionally engaged with and disengaged from a label in position to be applied about the periphery of the spool, and motive means for rotating the belts on the rollers while the belts are in frictional engagement with a label on the spool.

9. In apparatus for applying a label to the periphery of a spool, a cylindrical guide for guiding a label into cylindrical form about a spool in position to be labeled, and means for wrapping the label tightly against the periphery of such spool comprising a pair of endless belts each mounted on a pair of spaced rollers whose axes are parallel to the axis of the spool, a roller frame supporting each pair of rollers in their spaced relation, a roller shaft secured to one roller of each pair on the axis thereof and projecting beyond the roller frame, the roller frames being pivotally mounted on said shafts for swinging in a plane perpendicular to the axis of the spool, each pair of rollers in its respective frame being disposed on opposite sides of the spool, a lever system for swinging the frames simultaneously about their pivots both toward and away from the spool, whereby the faces of the belts at points between the rollers may be frictionally engaged with and disengaged from a label in position to be applied about the periphery of the spool, drive wheels on each of the projecting roller shafts and drive means interconnecting said wheels, and motive means for rotating the thus interconnected roller shafts and thereby rotating the belts on the rollers while the belts are in frictional engagement with a label on the spool.

ROLLAND B. LANGE.

No references cited.

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