US2475691A

US2475691A - Tension control mechanism

Info

Publication number: US2475691A
Application number: US626321A
Authority: US
Inventors: Gay M Bonebrake
Original assignee: WM Wrigley Jr Co
Current assignee: WM Wrigley Jr Co
Priority date: 1945-11-02
Filing date: 1945-11-02
Publication date: 1949-07-12
Anticipated expiration: 1966-07-12

Description

Filed Nov. 2, 1945 2 Sheets-Sheet 1 MMZZET ZZ MJJQ JA y 1949- a. M. BONEBRAKE 2,475,691

TENS ION CONTROL MECHANI S M Filed Nov. 2, 1945 2 Sheets-Sheet 2 4 am I P QM J INVENTOR. 66y Mfimzeralfe mww-w Patented JulylZ, 1949 UNITED. STATES PATENT 2,475,691 @j p TENSION CONTROLMECHANI S M GayM.Bonebrake, Chicago, 111., assignor a i Wrigley Jr. Company, Chicago, 11]., a;corpora--,.. tion ofIllinois 3 pplication November 2, 1945, Serial lilog zgggy- 4 Claims, 271-23) This invention relates to tension control mech- In this adaptation themachine includes a cupanisms, and more particularly to a mechanism port l0 upon which-supply rolls l2, l3 and I I of adapted to provide continuous control of the tens strip material may be suitably mounted in l a sion of a moving web or the like. i common plane for rotation in response totension My invention has for a general object the proapplied tothe strip material. 1 vision of an improved control mechanism for rege As an example ofa practical use, the material ulating the tension of a moving web or the like in the supplyroll I2 may be foil while themateby effecting controlled variations of the speed rials in the supplies" I3 and [4 are paperwalxed of a web feeding roll atone end of the portion on both sides andcellophanarespectively. Lamiof the web in which tension is to be controlled. nated stripmaterlalof this type is well adapted As another object my invention contemplates to the wrapping of gum,confections and the like; the* provision of l a tension control mechanism Webs l5, l6 and I1 drawn from the supply rolls adapted to use with webs of frangible material or l2, l3 and "II; respectively, are laminated and the like and which incorporates a resilient elesealedtogetherln osely juxtaposed relationship ment adapted to soften the controlling action of by passage betweeniclosely spaced and subst'anl the mechanism in a manner such that breakage or tially parallel rolls l8 and I9; bothof whicifldlls' tearing of the web due to sudden tension varlaare rotatably supported by the support It: wne tions is avoided. i or roll it is carried relative to the support I0" by*a The present invention has for a. further obcoaxial and. projecting shaft anddesirably is Ject the provision of a variablespeed feed roll 20 a heater roll hea to atemperature such thatl't drive mechanism and associated apparatus such softensthe wax on theweb It to provide a that the feed roll speed is responsive to the tension between the laminated layers. "The heatin of of a web or the like whichis moved by the feed the roll lflmay be accomplished byanysuitable roll. i a means, such as theprovision of electrical heating It is also an object of my inventionto provide elements. i l 1 l c a tension control mechanism for regulating the The roll i9is supported by coaxial projecting feeding of a web or the like and which is capable end portion 22 which projects through a bearing of. smooth and continuous, variations of speed in the support HLas shoWn in Fig.- 3? In addi jj between predetermined maximum and minimum tion to serving as a backing roll for the heer limits and responsive to the size of a loop in the roll l8, the roll it also serves as a driving roll or portion of the web in which the tension control is mo ivatin he Webs to draw the material r In iesired. the respective'supply rolls. n is, consequently;

Other objects and advantages of the invention desirable that the roll I! is provided with a survill be apparent from the. following description face c0vering'23of a material such as cork which ind the accompanying drawings in which similar hroughout the several figures: i Fig. 1 is a fragmentary side elevational and omewhat diagrammatic view of a portion of a iachine which incorporates a preferred form of W tension control mechanism; i

Fig. 2 is a fragmentary side sectional view with 1e section taken substantially on a. line 22 of 18.3; i

Fig. 3 is a fragmentary top sectional view with which project from thesupport" l0; "Likewi ie section taken substantially on a line 3 3 of rolls 2'! and were carried bys aasaz a ig. 1 and wherein certain parts arecut away respectively, which project outwardly fro illustrate details of construction; and support I0. g y .7 Fig. 4 is a fragmentary top plan view of a por- After passing between the output rolls 2'! N an of the structure shown in Fig. 3. 28, the combined web may pass toother part of Although there are various types of machines; complete machineto be cut for use, or may which my tension control mechanism is well. wound as'a supplyroll oflaminated ,ma ited, the exemplary embodiment herein dis- Thespeed of. the driven output roll or rollsde r. ised depicts its adaptation to amachine for ably is substantiallyconstant and correlatd'to ninating a plurality of webs ofst'rip material. the normal speed of the driven roll is.

- ingly secured to As operation of the machine continues in the process of laminating the separate layers of the combined web, conditions of operation, such as the variations and the sizes of the supply rolls l2, l3 and I4, vary the driving force necessarily applied to the web by the driven roll l9. Thus, to maintain substantially uniform' output of the combined web and to prevent tearing or breakage of the web between the driven roll l9 and the driven output rolls 21 and 28, means is provided which is responsive to the tension of the web between those driven rolls to maintain that tension at a practically uniform value by regu lating the speed of the driven roll l9.

For driving the driven roll l9, a drive shaft 34 is rotatably supported in coaxial alignment with the supporting end portion 22 of the driven roll l9 by a bearing 85 at one end of a support arm 38. In the disclosed embodiment of my invention, a flanged bracket 81 is secured to the support In and carries a projecting stub shaft 38 to which the other end of the support arm 38 is secured by a clamping portion 99, as shown in Fig. 3.

As an exemplary form of driving connection to the drive shaft 34, apulley 48 is secured to the outer end of the shaft by means such as a set'screw 42 and is driven by means such as a belt 43. A collar 44 is secured to the shaft 94 by means such as a set screw 45 on the side of the bearing 35 opposite the pulley 48 to determine the axial position of the shaft 84. v

In order that the speed of the driven roll l9 may be varied as the drive shaft 84 is rotated at a practically constant speed, a driving connection between the shaft 84 and the driven roll I9 is provided by variable speed transmission in the form of a planetary mechanism 48. The planetary mechanism 48 includes a sun gear 41 secured to the end of the shaft 94 and a concentrically disposed internal gear 48, between which gears are a plurality of pinions 49 which mesh with the internal and sun gears and are equidistantly spaced circumferentiallyof those gears.

In order to support the internal gear 48 and provide a partial enclosure for the planetary mechanism, flanged bearings 50 and 52 aresecured by fastening means, such as screws 58, to opposite sides of the internal gear. The flanged bearing 59 is rotatably carried 34 while the flanged bearing 52 is carried by projecting shaft portion 54 on the end of the projecting end portion 22 ofthe driven r011 l9.

A recess 55 is provided in the central portion of the end surface of the flanged bearin 52 to accommodate an annular plate 58 which is drivthe end of the shaft portion 54. The annular plate 55 rotatably carries the pinions 49 in their circumferentially spaced positions and thus provides a driving connection between the planetary mechanism and the driven roll l9.

It may be readily understood, by consideration of the described structure of the planetary mechanism 48, that when the internal gear 48 is free to rotate, there will be no rotary motion transmitted through the planetary mechanism to the driven roll l9 since the pinions will transmit the rotary motion of the sun gear 41 to the free running'internal gear. However, when the motion of the internal gear 48 is impeded to a predetermined extent, the pinions 49 will necessarily travel around the sun gear 41 and thereby transmit rotary motion to the driven roll. The rate of rotation of the driven roll l9 will deby the drive shaft pend upon the extent to which the motion of the internal gear is impeded and will be maximum when the internal gear is locked.

To accomplish the desired result of controlling the tension in the web in the present instance, the ratios of the gears of the planetary mechanism are preferably so related to the diameter of. the driven roll 19 that when the internal gear is locked, the web will be driven at a rate materially in excess of the rate of motion imparted to'the web by the driven rolls 21 and 28. Under these circumstances, normal tension will be maintained in the combined web 24 between the driven roll 19 and the driven rolls 21 and 28 when there is some rotary motion of the internal gear 48.

In order to effect the desired control of the operation of the planetary mechanism 48 in response to the tension of the combined web 24, I have provided a frictional control mechanism which includes a brake band 51 adapted to coact with a brake drum 58 which is secured to the outer surface of the internal gear 48. One end of the brake band 51 is adiustably secured to a bracket 59 on the support III by a clamp 88 having thereon a screw 82 which is threaded into a nut 83, said nut being rotatably secured to the bracket 59. The other end of the brake band i 51 is secured to one end of a lever 84 by means such as a clamp 85. a

As illustrated in Figs. 2 and'3, the lever 84 is rotatably supported on the projecting shaft 88 between one side of the bracket 81-and a loeating collar 88 which is secured to the shaft. The other end of the lever 84 ismovably connected through a motion transmitting linkage 81 to a brake control arm 88, which brake control arm is supported at one end for swinging movement by a shaft 89 projecting from the support Ill.

In the disclosed embodiment the linkage 81 includes an adjustable element comprising a rod 18 having its ends threaded into connectors 12 and 18, which connectors are rotatably connected to the end of an angularly projecting arm 14 of a support bracket 15 and to the end of the lever. 84 opposite the brake band, respectively. A spring 18 having one end anchored to the support l8 and its other end secured to a projecting arm 11 on the bracket 15 biases the brake mechanism to a position such that the brake band is released from the drum.

Downward swinging movement of the arm 88 in a clockwise direction, as viewed in Fig. 1, actuates the linkage 81 and lever 84 to tighten the brake band about the drum 58 so that frictional engagement is affected to control the rate of movement of the internal gear and thus to control the rate of rotation of the driven roll l8. In Order to utilize this controlling action of the variable speed transmission to effect control of the tension of the web between the driven roll l9 and the driven rolls 21 and 28, the arm 88 has a bracket 18 secured to its swinging end for rotatably supporting a movable roll 19.

Desirably, the normal position of the roll 18 is displaced to one side of the idler rolls 25 and 28 so that in passing between the idler rolls and over the movable roll, a variable loop is formed in the combined web 24. The biasing force of the spring 18 acts in opposition to the tension of the web against the roll 19 to determine the position of that roll and thereby to determine the operation of the planetary mechanism 48.

The provision of a sizable loop in the com bined web 2! between idler rolls 2! and 26 where the web passes over the movable roll 19 establishes a variable section in the'course of the web and prevents variations in tension from causing slippage or tearing the web.

As an additional factor, promoting smooth operation of the control mechanism and easing the variations of the control mechanism in response to sudden variations of web tension, I preferably make the arm 68 of resilient material having characteristics such that it will flex in response to variations of web tension and thereby help to absorb shock or sudden changes but will not flex desired controlling forces against the biasing force of the spring 16 and to apply braking force to the brake band 51.

While I have'illustrated a preferred embodiment of 'my invention, many modifications may be made without departing from the spirit of the invention, and I do not Wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a tension control mechanism for regulating the tension of a flexible web or the like in a machine including support means rotatably carrying thereon driven rolls in separated relationship and a pair of idler rollsbetween the driven which rolls the web passes, the combination comprising a planetary mechanism for driving one of said driven rolls, said planetary mechanism including concentrically disposed internal and sun gears and a plurality of intermediate pinions meshing with the internal and sun gears, driving means connected to the sun gear, a plate connected to the last mentioned roll and rotatably carrying said pinions, a brake drum secured to the internal gear, a brake band surrounding a portion of said brake drum, means adjustably anchoring one end of the brake band, a rotatably supported lever having the other end ing an idler roll rotatably mounted thereon at a position normally at one side of the pair of idler rolls so as normally to effect the formation of a loop, in the web passin around the last mentioned idler roll intermediate said pair of idler rolls, said flexible arm being connected to the other end of said lever, means biasing said flex,- ible arm in a direction away from said pair of idlerrolls and such that the brake band is separated from the drum, whereby increased tension in the web moves the flexible arm against the force of brake band against the drum.

2. In a tension control mechanism for regulatng the tension of a flexible web or the like in a nachine including support means rotatably carsaid biasing means and tightens said,

the concentric gears, means for drivlngly conmeeting said pinions to said one of the driven rolls,

4. In a tension control mechanism for regulating'the tension of a flexible web during movement of the web in one direction in a machine including support means tatably supported lever having the other end of the brake band secured to one end thereof, a flexible arm supported at one end thereof for swinging movement toward and from said pair of idler rolls and having an idler roll rotatably 1 from said pair at idler rolls and such that the brake band is retracted from the drum, whereby increased tension in the web moves the flexible Number arm against the force of said biasing means and 449,446 tightens said brake hand against the drum toin- 5 889,769 crease the speed of said first driven roll. 1,054,367 1,185,320 GAY M. BONEBRAKE. 1,404,081 a 1,455,916 REFERENCES CITED. m 1,763,594 2,043,354 The following references are of record in the 2,267.10,

file of this patent:

. 8 UNITED STATES PATENTS Name Hunter Mar. 31, 1891 Didier ..'June 2, 1908 mass Mar; 4, 1913 Holmes May 30, 1916 Auvil Jan. 1'1, 1922 Stevens May 22, 1923 Nelson June 10, 1930 Mallina June 9, 1936 Juiliard Dec. 23, 1941