US2695171A - Means for web feed correction - Google Patents

Description

Nov. 23, 1 5 R. B. COF'FMAN MEANS FOR WEB FEED CORRECTION Filed March 22, 1949 3 Sheets-Sheet 1 IHVEHTUP Peat/v5 6 0/7714 Nov. 23, 1954 RB. COFFMAN MEANS FOR WEB FEED CORRECTION 3 Sheets-Sheet 2 Filed March 22. 1949 Nov. 23, 1954 R. B. COFFMAN 2,695,171

' MEANS FOR WEB FEED CORRECTION Filed March 22. 1949 3 Sheets-Sheet 3 Ibranfpr F0552)" 5 (bf/W4 J6 x: W

United States Patent M MEANS FOR WEB FEED CORRECTION Robert B. Colfman, Cary, IIL, assignor to Colfman Manufacturing Corporation, Chicago, 111., a corporation of Illinois Application March 22, 1949, Serial No. 82,879 6 Claims. (Cl. 2712.6)

The present invention relates to improvements in the correction of web feed and more particularly relates to the substantial coordination of feed or the rate of feed or travel of a web of material with the operation of apparatus for acting upon or modifying the web or for utilizing successive sections of the web as the web is fed thereto.

As an example of an important use for the present invention candy bar wrapping machines will be referred to, although it will be readily apparent that many other uses can be found for the invention.

In candy bar wrapping machines a printed web or strip of printed paper, foil, cellulose acetate, film, or the like, is fed from a roll or reel of the material to a cut-off mechanism where the web is severed into sections of appropriate length to be wrapped about a candy bar in the further operation of the wrapping machine. Each section of the web has printed thereon, a label which in wrapping up the candy bar must be in proper registration with the article and for this purpose must be substantially centered on the web section or blank.

Due to many variables such as web shrinkage or stretching, machinery lags and tolerances, and the like, overrunning or underrunning of the web sections with respect to the cut-off mechanism is a constant problem.

An important object of the present invention is to provide an improved relatively simple, highly efficient method of and means for controlling the web feed to provide for the delivery of substantially uniform predetermined sections of the web to a point where the web sections are acted upon as by severance from the web.

Another object of the invention is to provide combined electrical and mechanical means for web feed control.

A further object of the invention is to provide an improved web feed control unit which can be conveniently installed for use with an existing machine such as a candy bar wrapping machine.

Still another object of the invention is to provide means which is controlled by variations in travel of the successive predetermined sections of a traveling web to a given point for correcting web travel or feed for substantially eliminating such variations.

Yet another object of the invention is to provide a method of and means for controlling incremental or sectional registration of a traveling web with a given point under conditions which require periodic correction, comprising i the continuous subincremental varying of the web feed between periodic corrections.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawings, in which:

Figure 1 is a diagrammatic and schematic illustration of a web feeding and control system embodying the features of the present invention.

Figure 2 is a side elevational view of the feed correction unit of the present invention.

Figure 3 is a vertical sectional view taken substantially on the line IIIIII of Figure 2.

Figure 4 is a vertical sectional detail view taken substantially on the line I.VIV of Figure 2.

Figure 5 is a vertical sectional elevation taken substantially on the line VV of Figure 4.

Figure 6 is a vertical sectional elevation taken substantially on the line VI--VI of Figure 4.

Figure 7 is a vertical sectional elevational view taken substantially on the line VIIVII of Figure 4.

Figure 8 is a vertical sectional view taken substantially on the line VIII-VIII of Figure 4.

Figure 9 is a horizontal sectional detail view taken substantially on the line IXIX of Figure 4; and

Figure 10 is a side elevational view of a timer and syn- 2,695,171 Patented Nov. 23, 1954 chronizing unit adapted for use in the present feed correc= tion system. I

In a candy bar wrapping machine, for example, a Web 15 of wrapping material is drawn from a supply reel or roll 16 by a set of feed rolls 17 and fed to a severing or cut-off mechanism 18 in which a rotary knife 19 cooperates with a stationary knife 20 to sever the strip or web into section of proper length for wrapping about a candy bar in the subsequent operation of the machine. The strip or web 15 is printed with a succession of label imprints 21 which are centered or otherwise in predetermined position on the respective sections into which the web is to be severed by the cut off mechanism 18. It is therefore important that feeding of the web 15 be coordinated properly with operation of the cut-off mechanism 18 to effect severance of the web on lines between the successive label imprints 21 so as to have the label imprints on the severed sections in proper position when wrapped about the candy bars or whatever article to which they are to be applied. For visual observance of cut-off registration, the web may be provided intermediate the label imprints 21, as along one margin, with imprinted registration color spots 22. Hence, when the cut-off knives 19 and 20 sever the web in predetermined relation to the registration spots 22, as by cutting through such spots, substantial registration is effected.

According to the present invention, variations from substantial registration of the registration spots 22 at cutoil are automatically corrected in the continuous operation of the machine, and such operation may be at high speed. For this purpose, a feed control unit 23 is drivingly connected with the feed rolls 17 by means such as a sprocket chain 24. The control or correction unit 23 is adapted to accelerate or retard web feed for correctional purposes and is electrically controlled by an electrical control circuit arrangement including a photoelectric cell scanning unit 25 which is appropriately disposed to focus on the margin of the web 15 carrying the registration spots 22. The scanner 25 is included in an electrical control circuit 27 including an amplifier 28 which is in control of a normally open relay switch 29.

In the arrangement shown in Figure 1, an optimum initial adjustment for operation is effected wherein registration of the registration spots 22 with the scanner 25 as the web 15 is fed thereby and the resulting electrical impulses generated by the scanner goes unnoticed by the correction unit 23. For this purpose, the electrical impulses from the scanner 25 while no correction is needed are shunted off to ground by an electrical shunt circuit 30 which prevents amplification of the impulses and closure of the relay switch 29.

In order to afford assurance that feed correction for the web 15 will be made periodically to meet the various factors which might cause either overrun or underrun of the web in operation, provisions are made for positive overrun or underrun of the web by small increments with respect to registration of the registration spots 22 with the cut-off 1S and then positive correction at periodic intervals as the successive registration spots vary to a predetermined limit out of the preferred optimum registration with the cut-off. For example, an incremental lag relationship is shown in Fig. l wherein as successive sections of the web 15 are cut off the web gradually lags until the permissible limit of variation from the optimum registration occurs and at which time a normally closed switch 31 in the shunt circuit 30 is opened in synchronism with the registration of one of the registration spots 22 with the scanner 25 and the resulting generation of an electrical impulse by the scanner.

As a result, such impulse is amplified and effects energization and closing of the relay switch 29 and closing of an energizing circuit 32 for a correction solenoid 33 which is energized to operate the correction unit 23 which functions to overdrive the feed roll assembly 17 sufficiently for one revolution to compensate for the lag in the web 15 and thus readjust the web to the initial optimum registration relationship of the registration spots 22 with the cut-off 18 or even slightly in advance of such optimum adjusted relationship. Promptly upon completion of the correctional adjustment of the traveling web 15 a normally closed reset switch 34 is opened to break a control circuit 35 for solenoid circuit 32, deenergization of the solenoid 33 and return of the control unit' 23 to its interim condition or r relationship in the system.

In one practical form, the synchronizing switch31- a-nd .1athezresettingrswitch 342 133 form part. of a;switch assembly unit 37; (Fig.;l) inwhichfthe switches are. disposed -.-:-;on-- respective; opposite sides'gof a shaft 38 which; maybe ;anyashaft;- that is. part of.-,the machinewith;which-the;web a controlling and correction system is v associated andwhich rotates; in somerpredetermined relationship or ratio to a shaft39 carrying the rotarycutoif blade 19 (Fig.1), The 1'; -rotation -ratio. ofthe; shafts may betone to one. Awcontrol cam-40; carried by the shaft-38 has a; lobe- 41 .engageable OI1CG:- in each-revolution of the-,shaft with; followers on -:.-respective switch :armsAZ and-.43 ,disposed; 180 .apart. ,,Through--this arrangement the cam,=lobe:41 alternately idefiects the switch arms 42 and 43'from thevclosedswitch -position into which the arms are normallybiasedby suitable spring means. ;;Thus,:each of the switches .31 and '34 "will be; opened momentarily once inieachrfull revolution 1 r of 1 the, shaft 38, and the switch openings twill occur- S cces- .sivelytandwith a time intervaledeterrnined bye neThaIf revolution of the,shaft%:38. The switch.;un it 37 may-be tequipped withappropriate attachment; bracket structure M44 by vwhich it can besecuredinservicerpositionpn a -.,-convenient fran1e portion of the associated machine.

Bothincrernental lag in the :web :feeduand correctional overdrive are effected by the correction anitrzii which is inathe form of compact unit mountedonor inassociation with a mounting panel:orflplateAiifig; 2).:which. is .xadaptedtobe secured in an appropriaterlocation on -the frame ofthe maehine with which-zthepresent web v -feed correction system isgused. On the,mountingqplate'45v is secured the solenoid 33. A shaft 47 which -rnaybe either ."astuhshaftcoupled: onto a shaft of -theimac hine ormay be ashaft of the machine rotating ingoperation in prefer- .v JQ'bIYJDHG toone ratio; with the.-cut;off shaft- 39, extends ficthlo'ugh a bearing aperture 48; in;;themounting plate and projects to a'substantial extentbeyond the outer face of:th e platetFig. 4). Rotatably mounted -.ori th e shaft 47 is drive means such as asprocket-49aabout whichxthe i webfeeddrivechain 24 is trained.

Means are provided fon:couplingathe;sprocket49 for 51' joint-"rotation with theshaft; 47:;and1 also for a, relative overrun rotation: oratunderrun :rotation as=:desired. I .To this-end, the sprocket 49t-has a tubular stub shaftsfifl con- :centrically-bearinged'taboutgthedrive;shaft*47 for ime s relative: rotation :and vextending: inwardly-along the; drive haft.,-,.Atitst;inner;-end and in spaced relation= tQ'gthfi procket 49:the1stub shaft has-fixedly;thereonqa toothed atchet wheeltassernbly; 5l-- which is preferably-madam ofa plurality-,2 herein shown as; three,; ratchet diskshaving the teeth progressively incrementally; otfset fortfine in- -1:1cremental1 .ratchetingi interconne tion 1 with a complementary 'set ofrcoaxially pivoted; identically formed; relatively rockable pawls 52; onesfor; cache of; the; ratchet plates XOf the ratchet wheel :assernbly; 51. .;The-;p ivot;for the "byadriver..disk-54 which is,::keyed orrotherwise fixedly unsecured torthe' drive;.shaft 47. iiTherelationship of the tratchetwheel :assembly--'51;.and;.the .pawls. 52 issuch that inpthe counterclockwise;rotation ofthe shaft47 as viewed insFigs'. 2 and 7:.the. drive. 'disk- 54-. thro ugh-=the ;.s.:rnedium ofithevpawls 52 drives theyratchet wheelrassem- 'bly.:51:and thus drives the sprocket;- 49 ;.rotat-ably .with

":lthe shaft 47.

..i 'Byi proper. selection of-the sprocket 491-pr0pery ratio isaprovidedr with respect to the feed rollasserhbly 17 to provide for. an underfeed of ,therwebxl5. to; the .1cutrotf :-:mechanism: 18..--. After a certain number. ofvdr'iving :revolutions of the shaft 47 and thus feeding of a certairrnumr'bert of-sections of the webY15.-.through;thecut oif 18,

correction is called forxbya the scanner .circuit as: ex-

TY lainedhereinabove,. and the; "solenoid-33 operated, :7 As

a-result; the solenoid draws a. connectingllinkiSitoward -the left as' viewed in. Fig. 2. from= =thefullrlineiposition to r the dot-dash. position: and rocks azrockzlever 57 pivotallymounted-on a stub shaft 58 carried byztthe mounting --plate 45.1 The-rockvlever. 57 isgyconnected asi'byameans I of aruniversal' ballijoint 59. with fizzllllk. fifiimvhich isxpivotally connectedas. at 61 "with an ear: 62 atgonesedge of an eccentric slide plate 63. :Oppositelongitudinak beveled a edge's 64 on :the vplate3'63 are slidably engaged irr. comple- 4, mentary bearing tracks provided by gib plates or bars 65 removably, secured to. the. mounting plate. 45,...and. providing a generally dove tail track or way for the eccentric plate 63. Thus, in rocking of the rock lever 57 by the solenoid 5 33, the eccentric plate 63 is correspondingly shifted as gidicated, from the full line to the dash line position in Shifting of the eccentric plate 63 causesa rotary disk 67 peripherallyrotatably bearinged' in a complementary central bearing-hole 68: in the plate to be moved into predetermined eccentric relation to the shaft 47which the diskg67 clears bymeans of; anaxial clearance aperture 69 of large enough diameter to afford a substantial range of eccentric movement of the diskwiththe eccentric plate 5,.163 relative to the: shaft 47. The disk 67 is connected ;by,means of a; pin 70 to one end portion of acontrol ;bar,'71- (Figs. 6-,and ;9) which is reciprocably slidably assembled within a hdiametricggroove or way72f recessed in the face of thedrive plate-54 which opposes the ec- Q-centric plate 1 63. t A longitudinal slot 73 inthe control bar clears theshaft 47.

-The opposite endportion of,the control bar 71projects substantially beyond ,the, peripheryof the. drive disk 54 and has a right angularly outwardly extending head -flange74 (Figs. 3 and-4) of atlengthto extend outwardly -,-beyond the -ratchetassembly:51and opposite the space between the sprocket 49 andthe ratchet wheel assembly.

,1; Secured to-the outer endlportion of the'head'fla'nge74,

as;by r neans of ascrew 75 is a stem 77 secured as by Q means of a-threadedqassemblywith one endof a'rack frames-78 internally dimensioned to clear the hollow stub shaft-Stttherethroughandalso to afford clearance for a .t piniony79;carried;by a transmission diskfit which is slidablyinterposed;between:the rack frame 78 and the .r-outerside o f the-ratchet wheel assembly 51 and is freely rotatabl-y bearinged onsthe-stubtshaft 50 (Figs 4, 8 and 9).: For convenience in assembly one sideof the rack frame 78 is; equipped with a-detachable rack bar 81. P;lay or sloppin ess in meshing: of the tteethof the pinion .579 andi-therackibar 8l is avoided by a tension spring 1.82 connected therebetween; as best seen in Fig. 8.

y The ;disk -80 is of larger diameter than-the ratchet wheel --.assem bly 51 and on its-inwardly facing margin the .plate carries a set f pawls 83 -(;Eigs. land-9)" which are pref- -,erably;;identical with the 'pawls 52 andinterengage with the ratchet disks of the assembly Sltontthe, diametrically oppositeside of the ratchet assembly. Pivot for the pawls -83 is proyided-by a pin 84carr'ied' by disk 80. Identical, ;.-=multi-finger ,leaf springs: 85, carried by respectively-the drive disk 54 and the transmissionqdisk 80 provideressilient ratcheting biasforathe sets of'p'awls52 and 33, re- +-;.sn :vy- Protective enclosure-for the transmission assembly is :raiforded-by a casing tube 87 carried fixedly peripherally by the drive disk 54 and in turncarrying an outer closure ;plate 88. ,An aperture-89 ingthe casingtube 87 affords ;;clear ance for-the rack frame stem- 77.' -Anaxial aperture -;-*90 in the closure plate :88 affords free rotary clearance v; for the'stub shaftLSt b0 ln operation ofH-the web feed-correction-runit 23, the

eccentric plate 63 is initially adjusted for-the particular -webbeingfedthrough the;associated machine by manipulation of a: turn buckle type of-adjustment thumb screw i .91 (Figs. land 3) in the -connectingulinkwi), if necessary for predetermined fixed eccentricity of; the rotary eccentric ,disk67 with-respect to hthev drive shaft 47 to effect advance of the .web 15 at a rate incrementally out of phase or synchronism with proper or optimum regis- .tration .or :thesections: 21 ,with 'the gCllt-Ofift 18. As' the shaft 47 rotates and carries with it the fixed drive disk: 54,

the slide membe1 71 is-carried with .the disk :54 and through the pin connection-:70, turns ,the eccentric 67 \B y reason of'the eccentric connection afforded by the pin N 70, it will be apparent,;the.slide member.-71- will be re- I 'ciprocated iniits; track 72; in; thedrive; disk 54 in each revolution of the shaft-47. {AS themember 71 reciproicates it tcarries with it;,the ;rack frame 78 and correspondingly rotates thepinion 79 and therebythe trans- .:;;mission disk- 80., yAs; theyrackzframe 78 moves on the 80 out-stroke sopthattthe. transmission 'disk 80 is turned Erclockwise as viewed; in Figs. ,7 and 8', the pawls 83 are carried counter the rotation; of the shaft 47 to'the ad- ;-'.,j. ust e d; extent determined'b'y :the eccentricity oftthe disk 67 in the; plate;63. As. thetrack :frame 7 8 moves on its in-stroke;; the pinion; 7. and; the transmission a plate 80 rotate in overrun relation to the shaft 47 and the pawls 83 act to turn the ratchet assembly 51 and thereby the stub shaft 50 and the sprocket 49 to the same extent, thus effecting an overdrive of the feed mechanism 17. This relationship is desirable where due to various factors the incremental lag in feed of the web 15 will not work out properly for the particular coordination predetermined in the correction system as a Whole to warrant one to one or concentric disposition of the eccentric plate 63. Hence, constant feed lag with partial Web feed correction in each cycle and a small incremental under correction that eventually accumulates after several cycles into a total lag requiring operation of the electrical system for a full web feed correction is provided. For example, adjustment may be such as to require a full correctional feeding overdrive on every eight to ten cycles or revolutions.

When the scanner 25 signals that the registration spots are running far enough behind the optimum registration desired with relation to the cut-off 18 to warrant full correctional overdrive, and the solenoid 33 is energized to effect maximum eccentricity of the eccentric plate 63, corresponding overdrive of the sprocket 49 is effected by the overdrive transmission. Deenergization of the solenoid 33 upon completion of the web feed correction releases the eccentric plate actuating linkage for return to the non-eccentric, or minor adjusted eccentric condition of the eccentric plate 63. Quick return of the actuating linkage is provided for by resilient biasing means such as a coiled tension spring 92 (Figs. 2 and 3) connected between an anchor pin 93 on the mounting plate 45 and the rock lever 57 The extent of the throw or operative rocking of the lever 57 is adapted to be adjusted by means of a stop screw 94 threadedly carried by a boss 95 and opposing return throw of the rock lever 57 under influence of the return spring 92. A lock nut 97 holds the stop screw 94 in adjusted position.

In order to facilitate a resetting of the correctional unit 23 for known conditions, a calibrated adjustment scale arrangement 98 is provided on the margin of the eccentric plate 63 and one of the track bars 65.

Although the correctional unit 23 has been shown in specific detail for overdrive correctional action, it is obvious that an underdrive correctional operation thereof can be readily provided for by simple changes involving merely reversal of certain parts.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

1. In apparatus including a rotary shaft, a web feed correction unit, a mounting plate having accommodation for operation of said rotary shaft therethrough, an eccentric plate slidably mounted on said mounting plate and having a disk rotatably supported thereby with its axis shiftable from concentricity with said shaft to an eccentric relation to the shaft by sliding shifting of said eccentric plate, a rotary member having bearing relation to the shaft enabling relative rotation of said rotary member, means for normally coupling the rotary member for joint rotation with the shaft, and means including a member coupled with said rotary disk and operable reciprocably relative to said shaft when said eccentric plate is moved to shift the axis of the disk to eccentricity relative to the shaft for acting upon said rotary member to drive the same rotatably relative to the shaft while the rotary member is rotating with the shaft.

2. In apparatus including a rotary shaft, a web feed correction unit, a support to be disposed in operative relation to said rotary shaft, a shiftable eccentric plate carried by the support and having a disk rotatably supported thereby with its axis shiftable from concentricity with said shaft to an eccentric relation to the shaft by shifting of said plate, a rotary member to be carried by the shaft and having bearing relation to the shaft enabling relative rotation of said rotary member, means normally coupling the rotary member for joint rotation with the shaft, means for adjusting the position of said eccentric plate for determining the eccentricity of said rotary disk, and means connecting said disk with said shaft and with said rotary member for cyclical incremental rotation of said rotary member relative to the shaft as governed by the eccentricity of the disk relative to the shaft.

3. In combination an apparatus for controlling a web feeding mechanism, a rotary drive member having a hollow shaft adapted to be relatively rotatably received upon a continuously rotating shaft, a ratchet wheel device carried by said hollow shaft in spaced relation to said rotary member, a drive coupling member adapted to be fixedly secured to the rotary shaft in face to face relation with the ratchet Wheel device, pawl means effecting a coupling between the coupling member and the ratchet Wheel device for joint rotation of the members, a transmission disk rotatably carried by said hollow shaft and having pawl connection with said ratchet wheel device, a pinion carried by said disk, a rack disposed in meshed relation to said pinion, and means for selectively reciprocating said rack to actuate said pinion and disk and rotate said ratchet device and hollow shaft and drive member relative to said coupling member.

4. In combination an apparatus for controlling a web feeding mechanism, a rotary drive member having a hollow shaft adapted to be relatively rotatably received upon a continuously rotating shaft, a ratchet wheel device carried by said hollow shaft in spaced relation to said rotary member, a drive coupling member adapted to be fixedly secured to the rotary shaft in face to face relation with the ratchet wheel device, pawl means effecting a coupling between the coupling member and the ratchet wheel device for joint rotation of the members, a transmission disk rotatably carried by said hollow shaft and having pawl connection with said ratchet wheel device, a pinion carried by said disk, a rack disposed in meshed relation to said pinion, and means for selectively reciprocating said rack to actuate said pinion and plate and rotate said ratchet device and hollow shaft and drive member relative to said coupling member, said rack reciprocating means including an angular member reciprocably carried by said coupling member.

5. In combination in a web feed control unit, a pair of rotary members mounted for rotary operation in unison and differentially, clutch mechanism effecting connection between said rotary members for said unison rotation and including means for effecting differential rotation of said rotary members during unison rotation of the members, said means including a member reciprocable transversely relative to said rotary members and rotatable in unison therewith, a non-rotary reciprocable member having thereon a rotary crank device coupled with said rotary and reciprocal member and operable by reciprocal shifting of said non-rotary reciprocal member to effect predetermined reciprocal movement of said reciprocal and rotary member for actuating said clutch mechanism to cause differential rotary movement of said rotary members.

6. In combination in a web feed control unit, a supporting structure, a member guided for reciprocal movement on said supporting structure, a member rotatably supported by said reciprocably supported member, a pair of rotary members rotatable in unison and differentially, clutch means connecting said rotary members for said unison and differential rotation, and means for controlling operation of said clutch means including a crank connection with said rotatably mounted member on said reciprocal member, said reciprocal member being movable in a fixed reciprocal path to alter the crank operation on said control means.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,273,627 Langmuir July 23, 1918 1,940,834 Apthorpe Dec. 26, 1933 2,033,857 Smith et al Mar. 10, 1936 2,035,201 Smith et al Mar. 24, 1936 2,048,194 Moreno July 21, 1936 2,066,415 Milmoe Jan. 5, 1937 2,080,575 Perry May 18, 1937 2,090,307 Potdevin Aug. 17, 1937 2,094,938 Blatzheim Oct. 5, 1937 2,095,125 Cornock Oct. 5, 1937 2,231,735 Pittaluga Feb. 11, 1941 2,251,306 Thompson Aug. 5, 1941 2,291,883 Craig Aug. 4, 1942 2,299,984 Horwitz Oct. 27, 1942 2,531,644 Rayburn Nov. 28, 1950

Images