US3377033A

US3377033A - Papermaking machine

Info

Publication number: US3377033A
Application number: US549716A
Authority: US
Inventors: Peter J Link
Original assignee: Kimberly Clark Corp
Current assignee: Kimberly Clark Corp
Priority date: 1966-05-12
Filing date: 1966-05-12
Publication date: 1968-04-09
Anticipated expiration: 1985-04-09

Description

P. J. LINK April 9, 1968 PAPERMAKING MACHINE 4 Sheets-Sheet 1 Filed May 12, 1966 April 9, 1968 P. J. LINK 3,377,033

FAPERMAKING MACHINE Filed May 12, 1966 4 Sheets-Sheet 2 April 9, 1968 P. J. LINK PAPERMAKING MACHINE 4 Sheets-Sheet Filed May 12, 1966 FIG.5.

April 1968 P. J. LINK 3,377,033

PAPERMAKING MACHINE Filed May 12, 1966 4 Sheets-Sheet 4 United States Patent 3,377,033 PAPERMAKING MACHINE Peter J. Link, Neenah, Wis., assignor to Kimberly-Clark Corporation, Neenah, Wis., a corporation of Delaware Filed May 12, 1966, Ser. No. 549,716 12 Claims. (Cl. 24256.2)

ABSTRACT OF THE DISCLOSURE A winder for paper or the like including a pair of spaced drums at least one of which is driven and which support a paper roll being wound between the drums, and power mechanism for moving one of the drums vertically as the paper roll is being wound so as to change the proportion of the weight of the roll of web carried by the respective drums. One of the drums is preferably covered with resilient material, and the drive of one of the drums may be changed with respect to the drive for the other drum as the paper roll increases in diameter.

My invention relates to papermaking apparatus and more particularly to winders for webs of paper or other sheet material.

Shipping rolls of bond, ledger and newsprint paper, and particularly coated book grades of paper, for example, are being requested in larger and larger diameters. As these rolls become larger, the roll quality is more difficult to maintain, and any cross deckle bulk or thickness variations in the webs are accentuated to the point where web failures in the rolls are produced, particularly roll bursts or splits in the web. The variations also cause difficulty in using the webs for printing in web feed printing presses, for example.

A large part of the trouble is caused by the winders with which the shipping rolls are wound and which provide increased nip pressures between the rolls of paper being wound and the winder rolls supporting and driving the paper rolls, as the paper rolls increase in diameter. These supporting drums in the winders are essentially incompressible while the paper roll is actually relatively resilient, and the deformation at the nips of the paper roll being wound and the supporting rolls results in less paper or web being furnished to the roll than necessary as the paper roll becomes greater in diameter and heavier. Consequently, the outer layers of the paper roll become tighter and more strained, and cross deckle web variations are more likely to cause trouble.

Similar troubles have been had with winders for winding large diameter rolls of tissue, particularly tissue of the creped variety which is usable for toweling and for cleansing tissue. With tissue, it is very desirable that the large parent rolls, from which the small rolls used by the consumer are made, shall be wound with uniform density inasmuch as varying roll density will produce varying product height in paper toweling and cleansing tissue and varying diameter of the rolls of bathroom tissue and wiping tissue. Any' such variations, of course, result in unattractive packaging or packaging difliculties.

Paper grades wound with ordinary winders are of an insutficient density near the core and are wound too tight near the outside diameter; in contrast, with wound parent rolls of tissue, the condition is reversedthere is excessive tightness or density near the core, and the rolls are wound much too loose near the outside diameter. This difference in the densities of the parent rolls results from the differences in the webs; the bond, ledger and newsprint paper, for example, is relatively incompressible and is relatively dense, while the tissue is relatively compressible and is relatively light.

It is an object of the present invention to provide im- 3,377,033 Patented Apr. 9, 1968 proved winders for webs of sheet material by means of which the densities of the rolls being wound may be varied from the core to the outside diameter of the rolls. More particularly, it is an object of the invention to provide such winders in which the densities of the web material near the core and also near the outside diameter may be increased or decreased, as desired.

Preferred forms of the invention include a pair of spaced winder drums disposed horizontally and parallel with respect to each other and both of which are driven so that a roll of web material may be disposed between and on the drums to thereby be wound, being turned by frictional contact with the drums. In order to provide the desired variation of density in the rolls being wound, one of the supporting drums is provided with a resilient outer surface having a hardness approximately that desired in the finished roll, and one of the supporting drums is mounted to be moved vertically on its axis with respect to the other roll, so that the vertically movable supporting roll takes more or less of the weight of the roll being wound as necessary to obtain the desired density. The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed, for carrying out the above stated objects, and such other objects, as will be apparent from the following description of preferred embodiments of the invention, illustrated with reference to the accompanying drawings, wherein:

FIG. 1 is a diagrammatic side elevational view of a winder embodying the principles of the invention shown together with a web supply;

FIG. 2 is a diagrammatic side elevational view of the winder shown together with control apparatus for the winder;

FIG. 3 is a side elevational view of one of the drive rolls of the winder, the view being taken substantially from line 3-3 of FIG. 2;

FIG. 4 is a diagram of a portion of the control apparatus for the winder;

FIG. 5 is a diagrammatic side elevational view of a winder constituting a modification of the invention;

FIG. 6 is a diagrammatic side elevational view of a winder together with a web supply and constituting another modification of the invention; and

FIG. 7 is a diagrammatic side elevational view of still another modified form of the winder of the invention.

Like characters of reference designate like parts in the several views.

Referring now to FIG. 1, the illustrated winder may be seen to comprise an unwind stand 10 carrying a roll 11 of paper or other web material and preferably having a conventional constant web tension mechanism incorporated in it. The paper or other web 12 from the roll 11 passes over a lead-in roll 13, a slitter 14 and a Mount Hope roll 15, and the roll 13 is preferably driven so as to draw the web 12 from the roll 11. The slitter 14 may be of conventional construction and may comprise a drum 16 and a slitter wheel 17 having a sharpened peripheral edge in substantial contact with the drum 16. The Mount Hope roll 15 is a conventional bowed roll in which the central axis of the roll bows from the supported ends of the roll for spreading the web 12 to prevent its wrinkling longitudinally.

The winder comprises a metal drum 18 and a drum 19 which is disposed adjacent to the drum 18 and on the same general level as the drum 18. The drum 18 is preferably grooved on its periphery, and the drum 19 is provided with a resilient covering 1911 on its periphery. Both of the

drums

18 and 19 are driven by conventional driving mechanisms, such as by electric motors 20 and 21 diagrammatically illustrated.

r The winder drum 19 is mounted with a fixed axis on any suitable winder support or base (not shown). The winder drum 18, disposed on about the same general level as the drum 19, is mounted so that it may be moved to have its longitudinal center either above or below that of the drum 19. The drum 18 is carried by and is rotatably disposed between vertically movable standards 22 and 23 (see FIG. 3). The

standards

22 and 23 are respectively elevated or lowered by means of elevating

screws

24 and 25 actuated by right angle gear

box screw drives

26 and 27. The

drives

26 and 27 are driven from a combined hydraulic motor and speed reducing gear box 28 connected by means of

shafts

29 and 30 with the

screw drives

26 and 27. The gear box 28 is driven in accordance with the increase in diameter of a roll of paper being wound, in order to elevate the drum 18 and shift the paper roll toward the drum 19, as the paper roll increases in diameter, in order to accomplish the results to be hereinafter described.

The paper web 12 passes underneath the drum 19 from the Mount Hope roll 15 and onto a core 31 which is positioned between the two

rolls

18 and 19. The end of the web 12 is fixed to the core 31, and the

rolls

18 and 19 are driven in the directions indicated so as to wind a paper roll 32 which is supported by the

drums

18 and 19. The core 31 on each end is disposed in a winder shaft support saddle 33 (see FIG. 2), and a saddle control chain 34 has its opposite ends connected to each saddle 33. Each chain 34 passes over

sprockets

35, 36, 37 and 38. A hand wheel 39 is fixed with respect to each sprocket 37 so that each saddle 33, together with an end of the core 31, may be adjusted with respect to the

drums

18 and 19, as desired, when the roll 32 is being started.

The sprockets are fixed on a rotatable cross shaft 40. A rheostat 41 is controlled from the shaft and is thereby also controlled in accordance with movements of the chains 34, saddles 33 and core 31. A sprocket 42 is fixed on the shaft 40 and is drive connected by means of a chain 43 with a sprocket 44 on the rheostat. A rheostat 45 (see FIG. 3), similar to the rheostat 41, is drive connected with the

shafts

29 and 30 by means of a sprocket 46 fixed with respect to the shaft 29, a sprocket 47 on the rheostat 45 and a drive chain 48 extending over the

sprockets

46 and 47.

The two

rheostats

41 and 45 may be disposed in a Wheatstone bridge circuit illustrated in FIG. 4 which comprises

fixed resistances

49 and 50 along with the

rheostats

41 and 45, The rheostat 41 is connected to the resistor 50 and the two are disposed between

junction points

51 and 52; and the rheostat 45 is connected to the resistor 49, and the two are also disposed between the

junction points

51 and 52. A source of voltage 53 is connected to the

junction points

51 and 52, and an electric relay 54 of suitable conventional construction is connected to the mid-points 55 and 56 between the rheostats and fixed

resistors

49 and 50. The relay 54 is of such construction that it provides a substantial current on its

output terminals

57 and 58 in response to an increase in voltage occurring across the

junction points

55 and 56 and applied on the relay 54.

A source of fluid pressure 59 is connected through a valve 60 with the combined motor and gear box 28, and an electric solenoid 61 is connected to the

output terminals

57 and 58 of the relay 54 so that the valve 60 is opened to drive the unit 28 and thereby the

shafts

29 and 30 with an increase in current output of the relay 54.

As the paper roll 32 increases in diameter, preferably the major portion of the drive is changed from the motor 20 to the motor 21 so that the resilient drum 19 takes up the drive from the steel drum 18. This shift in drive may be obtained by means of a rheostat 62 which, like the rheostat 41, is controlled from the shaft 40. The rheostat 62 is driven from the shaft 40 by means of sprockets 63 and 64 and a drive chain 65. The motor 20 is connected to a source of voltage from leads 66 and 67. A rheostat 68 is provided in the lead 66, and a switch 69 is connected to the rheostat 68 and has two positions in one of which it connects the rheostat 68 in series with the rheostat 62 and in the other of which it shunts out the rheostat 62.

A rider roll 70 is preferably provided on the top of the paper roll 32. The rider roll is supported by means of a pair of chains 71 each of which passes over

sprockets

72 and 73 to a counterweight 74. A single acting air cylinder 75 is provided below each counterweight 74, and the cylinders have their lower ends connected by means of air conduits 76 and 7611 with a four'way valve 77. The valve 77 is connected to an air pressure supply conduit 78 having a pressure control valve 79 therein. A pressure control valve 80 is connected by means of conduits 81 and 82 with the valve 77, and a cam 83 effective on the valve 81 is driven through a reduction gearing 84 from one of the sprockets 72. The valve 77 is of such construction that in one position it connects the air supply conduit 78 directly with the conduit 76; and, in another position, the valve connects the air supply conduit 78 with the conduit 82 and also connects the conduits 76 and 81 so as to thereby connect the

conduits

78 and 76 through the pressure control valve 80.

In operation, the paper Web 12 is threaded under the roll 13, through the slitter 14, over the Mount Hope roll 15 and under the resilient surfaced drum 19 to a core 31, and the end of the web 12 is fixed in a suitable manner onto the core 31. Initially, the metal drum 18 (which may be termed a front drum) is located at a lower level than the resilient surfaced drum 19 (which may be termed a back drum) with both the uppermost peripheral surface and also the center of the drum 18 being located at levels below the uppermost peripheral surface and center respectively of the drum 19. Therefore, the paper roll 32 as it starts to wind on the core 31 will have more of its weight supported by the metal drum 18 and less of its weight supported by the resilient surfaced drum 19. The

drums

18 and 19 are driven in the indicated directions in order to initiate winding on the core 31.

As winding is started, the electric motor 20 for the drum 18 is energized to deliver considerably more torque than that from the motor 21 driving the drum 19. The rider roll 70 is so controlled, when winding is started, so that the roll 70 exerts a considerable downward force on the paper roll 32, holding the roll 32 tightly in contact with the

rolls

18 and 19. Under these conditions, with the drum 18 carrying more nip loading or paper roll weight as well as delivering more torque; the paper roll 32, as it starts, will be wound quite tightly.

As the diameter of the paper roll 32 increases, the front drum 18 is slowly raised; and, at the same time, the effective weight of the rider roll 70 on the paper roll 32 is reduced. Also, the driving effect of the motor 20 for the drum '18 is reduced with respect to that of the motor 21 driving the resilient surfaced drum 19. Eventually the weight of the paper roll 32 is of a sufficient magnitude so that the 'weight of the rider roll 70 approaches zero and is raised from the winding roll. To maintain a nearly constant nip pressure of the drum 18 on the paper roll 32 as the roll 32 increases in diameter, the drum 18 continues to be raised with respect to the drum 19; and this has the effect of raising the nip loading or pressure between the paper roll 32 and the resilient surfaced drum 19.

As previously explained, with prior winders in which the two steel supporting rolls for the roll being wound are on stationary centers at the same level; a common cause of bursting of the paper rolls, as the rolls increase in diameter and weight with winding, is caused by the increased deformation of the paper on the surface of the roll being wound in the hips between it and the two steel supporting rolls, causing less paper web to be furnished to the roll than necessary. This is apparently due to the fact that the paper roll has a reduced circumferential surface and thus less surface speed in the nips due to the compression of the paper of the roll in the nips. The relative difference in action between the paper and supporting rolls is overcome when one of the supporting rolls is provided with a resilient outer surface approximating the paper roll in hardness, particularly if the weight of the paper roll being wound is increasingly supported by the resilient surfaced roll as the paper roll increases in diameter. Due to the fact that the cover 19a of the roll 19 has substantially the same resilience as the paper roll 32, a greater amount of paper web is furnished to the roll 32 as it is being wound, since the reduction of diameter of the resilient surfaced supporting roll is about the same as the paper roll at the nip between the two rolls as the nip pressure increases with increased paper roll weight and diameter. The bursting which occurred with two steel supporting and driving drums in a winder has thus been overcome, and at the same time, since the metal surfaced drum 18 takes most of the weight of the paper roll 32 and rider roll 70, as well as supplying most of the rotative force to the paper roll 32 as the roll 32 is being started, a tightly wound roll 32 is obtained at starting.

Therefore, using the Winder as above described, a uniformly tight paper shipping roll of practically any type of paper grade may be produced. Problems arising from variable diameter or length of the rolls will be substantially eliminated, and the same is true with respect to wound roll bursts due to excessive tightness of the web, particularly in the large diameters of the wound rolls. Draws of the web from the wound rolls in usage will also be more uniform and improved.

The change of drive from the front drum 18 to the back drum 19 in the illustrated winder control arrangement is obtained due to the action of the rheostat 62. The rheostat 62 is controlled from the saddles 33 for the core 31, and as the core 31 is raised due to the increase in diameter of the wound roll 32, the chain 34 moves over the

sprockets

35, 36, 37 and 38. Rotation of the sprocket 35 causes rotation of the shaft 40 and of the sprocket 63 which drives the sprocket 64 through the chain '65. The sprocket 64 controls the rheostat 62 so as to increase the resistance in the rheostat whereby less current is supplied to the motor 20 from the electric leads 66 and 67 as the core 31 raises. The rheostat 62 thus slowly unloads the motor 20 as the core 31 raises, thus transferring the winding load to the motor 20. It is contemplated that the rheostat 62 may also be so connected with the motor 20 in such a conventional manner that, as the diameter of the roll 32 approaches its maximum, the motor 20 may act as a generator; and thus the drum 1-8 will act as a brake while the drum motor 21 may be loaded to capacity. In one particular case, the motor 29 had a capacity of 60 hp. and the motor 21 had a capacity of 100 hp.; and, at the final large diameter of the roll 32, the motor 21 drove the drum 19 in its illustrated direction utilizing 100 hp. while the motor 20- braked the drum 18 to a capacity of 60 hp. It is assumed for this operation that the switch 69 is in its illustrated condition providing current from the rheostat 68 to the rheostat 62; however, any conventional desirable circuitry may be used in order to cause the motor 20 to act as a brake in the largest diameters of the wound roll 32. The switch 69, incidentally, may be moved into its other position, shunting the rheostat 62, for obtaining a manually controlled tight start on an empty core 31; and, in this case, the rheostat 68 may be utilized to load the motor 20 practically exclusively of the motor 21.

The drum 18 is raised from a position in which its center is below that of the drum 19 to a position in which its center is above the center of the drum 19, as the paper roll 32 increases in diameter, due to the action of the rheostat 41. The rheostat 41 is controlled from the shaft 40 by means of the sprocket 42 fixed on the shaft 40 and driving the rheostat sprocket 44 through the drive chain 43. As above described, the saddles 33 control the rotation of the shaft 40; and, therefore, the resistance of the rheostat 41 is controlled by the saddles 33. As the saddles 33 raise along with the core 31, the resistance of the rheostat 41 changes and puts it in a mis-match with respect to the resistance of the rheostat 45. The rheostat 45 is driven from the shaft 29 (see FIG. 3) through the

sprockets

46 and 47 and the chain 48, and thus the resist- "ance of the rheostat 45 varies with the rotative position of the

shafts

29 and 30 and thus with respect to the height of the front drum 18. The height of the drum 18 is changed by providing fluid pressure from the pressure source 59 (see FIG. 4) to the hydraulic motor and gear box 28 which drives the right angle screw drives 26 and 27 through the

shafts

29 and 30. The

drives

26 and 27 act on the

screws

24 and 25 so as to elevate the

standards

22 and 23 and the drum 18 as the

drives

26 and 27 are actuated.

With there being a mis-match between the resistances of the

rheostats

41 and 45, the Wheatstone bridge circuit illustrated in FIG. 4 is put out of balanced condition, and the relay 54 is energized. Energization of the relay 54 causes the solenoid 61 to be energized and opens the valve so as to effectively connect the fluid pressure source 59 with the motor and gear box 28. Thus, with a certain increase in height of the saddles 33 and core 31, the drum 18 is raised a corresponding amount; and, in actual practice, the motor and gear box 28 is slowly and almost continuously operative so as to cause relatively continuous rotative movement of the

drive shafts

29 and 30 and raising movement of the front drum 18.

It is contemplated that the rheostat 41 as connected into the Wheatstone bridge circuit neednot necessarily provide a linear upward movement of the drum 18 as compared with the upward movement of the saddles 33 and core 31. The weight of the paper roll 32 is a function of its diameter squared; and, therefore, preferably the upward speed of the drum 18 is less than the upward speled of the core 31 at larger diameters of the wound rol 32.

After the roll 32 has been completely wound, it must, of course, be removed from its position on top of the supporting

drums

18 and 19; and, for this purpose, the drum 18 is preferably lowered in this case to a substantially lesser height than that which is used during actual winding. For this purpose, the motor and gear box 28 may be connected with the pressure source 59 through any appropriate manually controlled valve (not shown). Under these conditions, the wound roll 32, after the saddles 33 have been disengaged, may be simply rolled over the drum 18 onto a suitable supporting table or platform (not shown).

As above described, preferably the effective weight of the rider roll is decreased as the weight of the paper roll 32 increases. The counterweights 74 are effective on the rider roll 70' by means of the chains 71 passing over the

sprockets

72 and 73, and these weights are of such magnitude as to completely raise the roll 70- from the upper most surface of the roll 32 if the Weights 74 are rendered completely elfective. The effectiveness of the weights 74 on the rider roll 70 is regulated by means of the air cylinders 75 arranged to move the weights upwardly when air under pressure is supplied to the air cylinders. Assuming that the rider roll 70 rests on the paper roll 32 as the roll 32 is being started, the rider roll 70 raises as the roll 32 increases in diameter. Under these conditions, the sprocket 72 is driven, and the sprocket 72 rotates the cam 83 through the gearing 84. The valve is a regulator valve; and, assuming that the valve 77 is set so that air pressure is provided to the conduit 82, the valve 80 provides a decreasing air pressure in the

conduits

81, 76 and 76a, and thereby in the lower ends of the air cylinders 75, as the rider roll 70 moves upwardly and as the paper roll 32 increases in diameter. This decreasing air pressure in the lower ends of the cylinders 75 allows the counterweights 74 to become increasingly effective to reduce the effective weight of the rider roll 70 on the paper roll 32, and finally the air pressure in the lower ends of the cylinders 75 is substantially zero and the counterweights 74 completely balance out the weight of the rider roll 70 and raise the rider roll from the paper roll 32. The Weight of the rider roll 70 is not needed as the roll 32 increases to large diameter, in view of the fact that the paper roll 32 has sufficient weight in itself when of large diameter to maintain relatively great nip pressures between the roll 32 and the

drums

18 and 19.

The four-way valve 77 may be set so as to directly connect the conduits '76 and 78 for manual control of rider roll position, and the regulating valve 79 may be manually operated for adjusting the effective bearing pressure of the rider roll 70 with respect to the paper roll 32, particularly for start-up purposes.

For coated book paper, the P & J plastometer hardness (Vs-inch ball) has been found to be between and 40, the measurements being made on rolls of substantial diameter such as from 25 to inches. It is desired, as above mentioned, that the covering 19a on the drum 19 have approximately the same hardness as the rolls of paper to be Wound; and, therefore, the covering 190 should also preferably have this hardness when winding this type of paper. The covering 19a, for example, may :be up to and greater than four inches thick and may be made of wool felt, cotton, nylon or other relatively resilient materials. The materials used for the covering 19a should preferably have about the same flow characteristics under pressure as does a roll of paper, without the ability to move substantially circumferentially about the roll as the roll passes through a nip between it and a hard surfaced roll. Wool felt, cotton and nylon, as well as paper in a roll, have this characteristic, while rubber is not considered as suitable, since rubber tends to flow circumferentially within a roll as a rubber surfaced roll rotates through a nip with a hard surfaced roll.

Although I have illustrated the Winder as being used with the paper web 12 passing underneath the back drum 19 and thence passing from the surface of the drum 19 onto the core 31 which rotates in the clockwise direction, the paper web 12 may also be introduced into the winder in a number of different other ways by providing, in some cases, a proper re-arrangement of guide rolls for the web 12. For example, referring to FIG. 1, the

web 12 may be drawn from underneath the front drum 18 without contacting the rear drum 19 and passed over the right peripheral surface of the drum 18, thence over the top peripheral surface of the drum 18 to the core 31, with the core 31 and the resulting paper roll 32 rotating in a clockwise direction and the drums being driven in the counterclockwise direction. Alternately, the web 12 may be passed over the top of the back drum 19 to a core 31. In this case, the

drums

18 and 19 are reversed in direction so that they rotate in the clockwise direction (FIG. 1), and the core 31 and the resulting paper roll 32 rotate in a counterclockwise direction. As another alternative, the paper web 12 may pass from below and between the

drums

18 and 19 and on the left peripheral surface (FIG. 1) of the front drum 18 to the core 31. The

drums

18 and 19, in this case, rotate in the clockwise direction, and the core 31 and resulting paper roll 32 rotate in the counterclockwise direction. As another alternative, the web 12 may be introduced into the winder by passing it from the left side (FIG. 1) of the winder, under the rider roll 70 to the upper peripheral surface of the paper roll 32 being wound. In this case, the

drums

18 and 19 rotate in the counterclockwise direction; the paper roll 32 rotates in the clockwise direction; and the rider roll 70 rotates in the counterclockwise direction. As a further alternative, the web 12 may be passed over the top of the rider roll and thence around the right peripheral surface (FIG. 1) of the roll 70. In this case, the

drums

18 and 19 are driven in the clockwise direction; the web 12 passes onto the surface of the paper roll 32 in the nip between it and the rider roll 70; and the roll 32 and rider roll 7%] rotate in the counterclockwise and clockwise directions, respectively.

With any of these different manners of web introduction to the winder, the winding principles as discussed above, utilizing the resilient covered drum 19 and the mechanism for raising the front drum 18, will permit density control of the wound roll 32 by controlling the tension with which the Web 12 is wound onto the roll 32.

As further alternatives, in lieu of providing the back drum 19 with the resilient cover 19a, the back drum 19 may instead be steel surfaced while the front drum 18 may be the one provided with a resilient cover. Furthermore, although I have illustrated the front drum 18 as being the one that is vertically movable, the back drum 19 can instead be the one that is made to move vertically as the paper roll 32 increases in diameter. Also, as will be understood, the principle of the invention is not limited to having the drum with the resilient cover located in a fixed position, but this particular drum may be made to be the one that moves in a vertical plane as the diameter of the wound roll 32 increases. In all of these cases, the density of the wound roll 32 may be controlled as above mentioned, utilizing the principle of controlling the tension of the web 12 as it is applied onto the surface of the roll 32 being wound.

The movable drum for supporting the paper roll 32 may be pivotally mounted instead of being movable strictly in a vertical plane. Such a pivotal mounting is illustrated in FIG. 5 for the movable drum 18a. The drum 18a is rotatably disposed in ends of levers pivotally mounted on the fixed shafts 86. A screw 25a driven from right angle drives 27a, for example, may be utilized to be effective on the lower ends of the levers 85 for the purpose of elevating the drum 18a.

A winder particularly for tissue, and more particularly creped tissue (as distinguished from relatively heavy basis weight, uncreped paper), is illustrated in FIG. 6. This winder is quite similar to the winder previously described except for some rearrangements of the parts. The paper roll 90, from which the tissue web 91 is drawn for winding into a roll, is supported by a stand 92. The Web 91 passes under a lead-in roll 93, through a pull roll section 94 and through a slitter section 95. The winder comprises two supporting drums, a resilient surfaced back drum 96 and a steel front drum 97. The paper web 91 passes from the slitter section 95, around the hard surfaced drurn 97 and onto a core 98; and a rider roll 99, similar to the rider roll 70, is preferably provided to be effective on the top of the tissue roll being wound onto the core 98. The roll 97 is mounted to be vertically movable, similar to the previously described rolls 18 and 18a, and its vertical movement may be controlled in the same manner as is the vertical movement of the

rolls

18 and 18a.

The tissue winder illustrated in FIG. 6 operates much like the winder for paper illustrated in FIGS. 1 to 5, except that the movable front steel drum 97 is initially positioned at a higher level than the resilient surfaced back drum 96, and the front drum 97 is lowered as the wound roll 100 increases in diameter. This lowering may be accomplished using the same mechanism as previously described for the drum 18 but arranged to act reversely. There are motor drives for each of the

drums

96 and 97, and these may be controlled by rheostats similar to the rheostat 62; however, in the case of tissue, preferably the back resilient drum 96 contributes the major share of the drive to the roll 100 as the roll 100 is being started. The rider roll 99 may be controlled in substantially the same manner as the rider roll 70; however, it is contemplated that for tissue the rider roll 99 is preferably manually actuated so that the hardness of the roll 100 may be regulated as desired. The pull roll section 94 is driven; and, by regulating the drive to the section 94, the tension with which the tissue is supplied to the roll 100 may be regulated so as to increase and decrease the tension with which the web is wound into the roll 100 as desired.

As previously mentioned, in the case of tissue, the wound web near the core for the roll has in the past generally been wound too tight. More looseness of wind is attained if the major weight of the core 98 and roll 100, as the roll 100 is being started, is taken by the resilient surfaced drum 96; and, therefore, in the case of tissue, the front steel drum 97 is initially elevated with respect to the back drum 96. Initially, controlling the drives for the

drums

96 and 97, so that the back resilient drum 96 contributes the minor share of torque, also helps to provide a softer roll 100 near the core 98.

As the roll 100 increases in diameter, the front steel drum 97 slowly lowers, and this results in the front drum 97 taking an increasing portion of the weight of the roll 100. The steel drum 9'7 acts to provide a harder wound roll 100 as the roll weight on the drum 97 increases, and this is desirable in the case of tissue. At the same time, the drive distribution between the two

drums

96 and 97 is preferably changed so that, as the front drum 97 lowers, the drive motor for the front drum takes a decreasing port-ion of the load; and this also helps in firming the wound roll 100 as it increases in diameter, which is desinable in the case of tissue. Obviously, the density of the roll 100 may be regulated as desired simply by changing the manner in which distribution of drive between the

drums

96 and 97 is changed and the manner in which the drum 97 is lowered as the tissue roll 100 increases in diameter.

In the case of tissue, the resilient surfaced drum 96 also has preferably approximately the same hardness as the wound tissue r-oll 100. A desired P & J plastometer /s -inch ball) hardness of a roll of creped tissue may be about 150, which is considerably softer than the desired hardness of a roll of ordinary coated paper, for example; and, therefore, a layer of wool felt, cotton or other resilient material on the drum 96 should be less compacted as for use with papeigin order to be softer.

The winder illustrated in FIG. 7 comprises resilient surfaced back and front drums 102 and 103 and an intermediate steel drum 104 disposed between the drums 102 and 103. All three of the

drums

102, 103 and 104 are preferably driven from appropriate electric motors, and the drum 103 is preferably positioned at a lower level than the drum 102.. The drum 104 is vertically movable, and its vertical movement may be controlled by the same mechanism as is provided for moving the

drums

18 and 18a vertically. The web 105 being wound comes from a slitter, such as the s-litter 95, and the winding arrangement illustrated in FIG. 7 is so arranged that paper rolls 106 and 107 may be wound on opposite sides of the vertically movable drum 104.

In operation, a pair of wound rolls 106 and 107 is provided. The web 105 is slit, and one portion of the slit web is wound as the roll 106 and another portion is wound as the roll 107 on opposite sides of the center steel drum 104. Thus, possible interweaving between narrow slitted portions of the web as they are wound into rolls, is obviated-this interweaving has been found to occur at times with ordinary two-drum winders used in connection with narrow slit webs preventing ready separation of the roll segments.

The densities of the rolls 106 and 107 is controlled by movement of the center steel drum 104 vertically. In connection with paper, the drum 104 is preferably raised from a position below the centers of both of the resilient surfaced drums 102 and 103 to a position above the centers of these rolls; while, in the case of tissue, the steel drum 104 is preferably lowered from a position above the centers of the rolls 102 and 103. The relative proportions of the drives taken by the

drums

102, 103 and 104 may also be controlled in order to control the densities of the rolls 106 and 107. It will be noted that the front drum 103 has its center located below that of the back drum 102. Since the web 105 first contacts the intermediate steel drum 104, the hardness of the wound rolls 106 and 107 will tend to be some different, and the roll 106 will tend to be harder than the roll 107. Therefore, the resilient surfaced drum 103 is positioned lower than the drum 102 to take .more of the weight of the roll 106 than the amount of weight taken by the resilient surfaced drum 102 with respect to the roll 107. In order to obtain similar results but maintaining the centers of the rolls 102 and 103 on the same level; if desired, the hardness of the coverings on the two rolls 102 and 103 may be made different, the covering on the roll 103 being softer than that on the roll 102.

In the case of tissue, in order to provide a softer roll start, the intermediate roll 104 is elevated well above the fixed position of the back drum 102 and front drum 103, and initially the drives to the front drum 103 and back drum 102 carry the major drive torque. I-f increased roll density is desired, the front and back drums 103 and 102 may have their drive torque reduced, and this automatically increases the drive torque of the intermediate drum 104. To control density, the vertical position of the intermediate drum 104 may be changed, and more or less winding roll weight can be transferred from the relatively soft or covered .back and front drums 102 and 103 to the intermediate steel drum 104. Also, in accordance with conventional practice, a rider ro'll .may be provided on each of the rolls 106 and 107, and the weight of this may be more or less offset.

1 It will be apparent that various changes, which correspond generally with those alternatives mentioned in connection with the first embodiment of the invention,

may also be made with respect to the embodiments illustrated in FIGS. 5, 6 and 7, these alternatives being with respect to the various manners in which the paper web may be introduced into the winder, the particular drum provided with a resilient cover, and the particular drum which is changed in vertical position as the wound roll of web increases in diameter.

The usage of a filled, relatively soft, supporting drum in a two drum winder in connection with a relatively hard supporting drum, with one of the drums being relatively movable vertically, allows the hardness of a paper roll to be controlled as desired, and preferably the height of the movable roll is programmed to the diameter of the roll being wound for the best results. It will be noted that, with respect to the various forms of the invention, if it is desired to wind a relatively hard paper roll, the paper roll is made to bear principally on and be supported by a non-flexible steel drum, while if it is desired to wind a paper roll with less hardness, the paper roll is made to be principally supported by a drum with a resilient surface. Changing the driving torque from the inflexible drum to the resilient surfaced drum and vice versa also has the effect of winding softer or harder respectively; and, therefore, the two effects are preferably combined for the best control of paper roll density. The threedrum arrangement illustrated in FIG. 7 allows a narrow slit web to be wound into spaced rolls Without any possibility of interweaving at the sides of the wound rolls. It will be noted, from the FIG. 7 structure, that it makes some difference with respect to roll density as to whether the uppermost drum of each drum pair supporting a particular paper roll being wound rotates upwardly or downwardly with respect to the paper roll. Due to the direction of rotation of the relatively high intermediate steel drum 104, the paper roll 106 tends to be lifted by the drum '104 while the paper roll 107 tends to be de pressed by the drum 104. Therefore, the resilient surfaced roll 10 3 should preferably be lower than the resilient surfaced roll 102, since a resilient surfaced drum winds softer than a hard drum and is more effective with the greater proportion of the weight of the paper roll that it carries.

I wish it to be understood that the invention is not to be limited to the specific constructions, arrangements and devices shown and described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art that changes may be made without departing from the principles of the invention.

What is claimed is:

1. A winding apparatus for forming a convoluted roll from a continuous web comprising a pair of spaced windind drugs extending substantially parallel with each other and forming a core receiving nip portion therebetween, means for driving at least one of said drums so that the Web may be Wound into a roll within said nip portion with the roll resting on both of said drums and means for moving one of said drums through a substantial vertical distance as the roll of web carried by said drums is being wound so as to change the proportion of the weight of the roll of web carried by the respective drums and to thereby change the winding action of the drums.

2. A winding apparatus as set forth in claim 1, one of said drums having a peripheral surface which is softer than the peripheral surface of the other drum so that the drums have consequent different winding actions on the roll of Web being wound.

3. A winding apparatus as set forth in claim 2, and web roll diameter sensing means changing with the increase in diameter of the web roll being wound, and power means under the control of said sensing means for moving vertically one drum as previously mentioned as the web roll increases in diameter.

4. A winding apparatus as set forth in claim 3, said power means being operative on said winding drum with the relatively hard peripheral surface to elevate the relatively hard drum as the diameter of the roll of web increases.

5. A winding apparatus as set forth in claim 3, said power means being operative on said winding drum with the relatively hard peripheral surface to lower the relatively hard drum as the diameter of the roll of web increases.

6. A winding apparatus as set forth in claim 3, said driving means being arranged to drive both of said drums and means for changing the drive torque applied to one of said drums as compared to the drive torque applied to the other drum as one of said drums is moved vertically as aforesaid.

7. A winding apparatus as set forth in claim 6, and a rider roll riding on the upper peripheral surface of said roll of web as the web roll is being wound, and means responsive to said sensing means for changing the effective bearing pressure of said rider roll on said web roll as the web roll increases in diameter.

8. A winding apparatus as set forth in claim 2, and a second winding drum having a relatively soft peripheral surface and closely spaced with respect to said relatively hard surfaced winding drum and extending parallel thereto and forming a nip portion with the hard surfaced winding drum, and a slitter for slitting the Web whereby relatively narrow rolls from said web may be simultaneously wound in said two nip portions.

9. In a method for winding a convoluted roll from a continuous web, the steps which comprise, supporting a core in a nip portion provided between two spaced parallel winding drums, fixing the web onto the core and driving at least one of said drums so as to wind the web into a roll about the core, and moving one of said drums through a substantial vertical distance as the web is being so wound so as to change the nip pressure of the roll of web being wound with respect to one of the winding drums as compared to the other.

10. In a method for winding a convoluted roll as set forth in claim 9, one of said drums having a relatively soft peripheral surface and the other drum having a relatively hard peripheral surface.

11. In a method for winding a convoluted roll as set forth in claim 9, one of said drums having a relatively soft peripheral surface and the other drum having a relatively hard peripheral surface, and the drum having the relatively hard peripheral surface being elevated as the web roll increases in diameter.

12. In a method for Winding a convoluted roll as set forth in claim 9, one of said drums having a relatively soft peripheral surface and the other drum having a relatively hard peripheral surface, and the drum having the relatively hard peripheral surface being lowered as the web roll increases in diameter.

References Cited UNITED STATES PATENTS 670,187 3/1901 Simpson 242-56 2,323,003 6/1943 Baur 24256.3 X 3,306,547 3/1967 Reid et al. 242-66 LEONARD D. CHRISTIAN, Primary Examiner.