US2288350A

US2288350A - Supporting device

Info

Publication number: US2288350A
Application number: US239562A
Authority: US
Inventors: Walter T Gollwitzer
Original assignee: Multigraphics Inc
Current assignee: AB Dick Co
Priority date: 1938-11-08
Filing date: 1938-11-08
Publication date: 1942-06-30
Anticipated expiration: 1959-06-30

Description

June 30, 1942- w. T. GoLLwlTzER SUPPORT NG DEVICE Filed Nov. 8, 1958 4 Sheets-Sheet l wey.;

June 30, 1942.

W. T. GOLLWITZER SUPPORTING DEVICE Filed NOV. 8, 1958 4 Sheets-Sheet 2 N24 wf Y@ 159 June 30, 1942. w. T. GOLLWITZER SUPPORTING DEVIC E Filed Nov. 8, 1958 4 Sheets-Sheet 5 Eilll llii? -NWN June 30, 1942. w. T. GoLLWlTzER SUPPORTING DEVICE Filed Nov. 8, 1958 4 Sheets-Sheet Patented June 30, 1942 sUPPoa'rlNG DEVICE Walter T. Gollwitzer, Euclid, Ohio, assigner to Addressograph-Multlgraph Corporation, Wilmington, Del., a corporation of Delaware Application November 8, 1938, Serial No. 239,562

11 Claims.

This application is in part a continuation of my application, Serial No. 78,681, filed May 8, 1936, and also in part a continuation of my application, Serial No. 221,841, filed July 28, 1938.

This invention relates to supporting devices especially adapted for use with printing or other machines to which a paper web or the like is supplied to have impressions made thereon, to be divided into sheets, or to have other operations performed thereon. The machines of Patent No. 1,955,806, patented April 24, 1934, or Patent No. 2,041,183, patented May 19, 1936, are typical of such machines.

The primary objects of the invention are to support a roll of paper or the like so that a web may be withdrawn therefrom and supplied to a machine of the kind above identified or other machine utilizing a web; to maintain uniform tension on a web as it passes into a machine; to facilitate mounting of a roll in web withdrawing position; and to impart an unwinding movement to a roll and thereby expedite withdrawal of a web therefrom.

Other objects are to prevent unwinding of a web from a roll more rapidly than the web can be utilized in the machine to which it is supplied; to detachably and adjustably associate a support for a roll in such relation with a machine utilizing a web that proper feeding of a web withdrawn from the roll into the machine will be insured; to enable adjustment of the position of ff. roll in the support therefor; and to provide a novel supporting device of simple and economical construction and efficient and positive operation.

Selected embodiments of my invention are illustrated in the accompanying drawing wherein Fig. 1 is a side elevation of an apparatus embodying one form of my invention;

Fig. 9 is a view, similar to Fig. 8, showing the parts in a different operative position;

` Fig." 10 is a view, similar to Fig. 1, showing another form of my invention;

Fig. 1l is a top plan view of the form of the apparatus shown in Fig. 10;

Fig. 12 is a sectional detail view taken substantially on the line IZ-IZ on Fig.' 10

Fig. 13 is still another view, similar to Fig. 1, and showing a further modified form of my invention;

Fig. 14 is a front elevation ot the apparatus illustrated in Fig. 13, while Fig. l5 is a top plan view; and

Fig. 16 is a wiring diagram.

The form of my invention shown in Figs. 13 to 16 is illustrated in association with a fragmentally illustrated machine M which, in the present instance, embodies a printing couple including a printing cylinder A and a platen cylinder B to which a rotary movement is imparted in the operation of the machine whereby impressions may be made on a web W withdrawn from a roll R and passed between the cylinders A and B. The particular type and construction of the machine and the mechanism to which a web is fed form no part of my invention which particularly relates to supporting the roll R and the withdrawal `o1.' the web W therefrom, the printing couple shown merely being illustrative of a mechanism to which a web is supplied.

My novel supporting device, as illustrated in the accompanying drawing, embodies a pair of

stands

5 and 5 preferably provided with substantial base portions 1 and 8 that are adapted to be rested on a floor or other suitable support. Tie rods, such as 9, interconnect the base portions 'I and 8; a bar I0 extends between and interconnects the upper ends of the stands 5 and E; and these stands and tie rods and the bar provide the frame of my supporting device.

A shaft Il extends between and is journaled in the

stands

5 and 6 near the upper ends thereof. A sprocket i2 is fast on theshaft l l inwardly of and adjacent the stand 5 anda sprocket I3 is fast on the shaft ii inwardly of and adjacent the stand 6. Two strips i4 and i5 are secured to the inner side of the stand 5 in spaced apart relation and the adjacent sides thereof are undercut. A block i6 has the side edges thereof shaped complementary to the undercut edges of the strips I4 and l5 and is mounted between the strips and I5 for sliding movement. One end of a chain I1 is secured to the block IB and this chain is directed about the sprocket l2 and that portion thereof opposite the end secured to thev block i6 freely depends from the sprocket in spaced relation with the strip i 5. A chain I8 is directedabout the sprocket I3 and is connected to a block similar to the block I6 that is mounted for sliding movement between strips, similar to the strips I4 and I5, fast on the inner side of the stand 6.

A gear i5 is fast on the shaft il outwardly of the stand 5. A pinion is mounted on a stub shaft 2l fast in the stand 5 and meshes with the gear i5. A handle 22 is suitably connected to the pinion 2li and by grasping this handle a rotative movement may be imparted to the pinion to thereby rotate the gear i5 and consequently the shaft Il. Inasmuch as the sprockets i 2 and l5 are fast on the shaft li the rotative movement imparted to this shaft causes the chains il! and l5 to be moved whereby the blocks, as it, slide relative to the strips, as lll and l5, the direction of movement of said blocks being dependent upon the direction of rotation l of the shaft M.

A pawl 25 is pivotally mounted on the stand 5 and is engageable with the teeth of the pinion 25 to prevent rotation of said pinion. A rod 2Q extends outwardly from the free end of the .pawl 25 and a ball 25 is provided at the free end' of this rod. The ball 25 may be grasped to pivot the pawl 23 from engagement with the pinion 25 but normally this ball urges the pawl into engagement with the teeth of said pinion.

A plate 25 is secured to the bloclr l5 and projects rearwardly therefrom and beyond the stand l5. A similar plate 2li is connected to the block mounted on the stand 5. A pair of

rollers

25 and 25 are rotatably mounted on the inner side of the plate 25 and the adjacent portions of the peripheries thereof are arranged in spaced relation whereby a shaft, axle or the like may 'be rested on said rollers. A pair of rollers 35 and ill are similarly mounted on the plate 2 for a like purpose, the rearwardly and forwardly disposed rollers of each pair being in alignment transversely of the device. The pairs of rollers aord an anti-friction support for a shaft, axle or the like rested thereon.

The roll R includes a spool and a shaft or axle 52 is passed through the opening in this spool and provides a support for the roll. A collar 55 is fast on the axle 52 inwardly or" one end thereof and one end of the spool of the roll R is engaged with this collar. That part of the axle 52 on the side of the roll opposite the collar is screw-threaded, as indicated at 5G, and a split nut 55 is mounted on the screw-threaded part 55. The split nut 55 includes a conical portion 25 and the nut 35 is adapted to be run along the part 55 to wedge the conical portion 55 in the adjacent end of the opening of the spool of the roll R whereby the roll is firmly clamped between the collar 55 and the portion 55 to be held against rotation on the axle 52. When the portion 35 is in position to tightly clamp the roll,

the wing nut 5l (Fig. 15) on the split nut 55 is tightened to thereby secure the nut in position and maintain the clamping of the roll R.

That part of the axle 32 beyond the screwthreaded part 55 is of reduced diameter and this part, indicated by 55, is also screw-threaded. A

hand nut 55 is mounted on the screw-threaded part 55 and has a bifurcation lil therein. The rollers 5@ and 3l are adapted to be ntted in the bifurcation l5 when that .part of the axle 32 outwardly of the collar 55 is rested on the rollers '25 and 25. Then by turning the hand mit 55 relative to the screw-threaded part 35 the axle 52 may be moved axially whereby the transverse msition of the roll R intermediate the

stands

5 and 5 may be adjusted. When the roll R is in the desired transverse position the lock nut lli on the screw-threaded part 32 is engaged with aaeasso rotation relative to the screw-threaded part 88 and thereby retain the roll in the desired transverse position.

A pair of plates l2 and' l5 are adjustably mounted on the bar i5 in spaced relation with each other. Slots ill and l5 extend downwardly from the top edge of the plate d2 for a short distance and are located near each end of the plate. Similar slots are provided in similar locations in the plate (i3. A roller l5 has pins at opposite ends thereof and one of these pins is mounted in the slot lil and the other pin is mounted in the similarly located slot in the plate 33. Another roller il has pins at opposite ends thereof and one oi' these pins is mounted in the slot l5 and the other pin is mounted in the aligned slot in the plate (l5. Thus, the rollers and lil are supported for rotative movement between the plates l2 and 65.

A slot l5 is provided in the plate G2 midway between the ends thereof and a similarly located slot l5 is provided in the plate 55. The slots llt and i5 extend substantially throughout the height of the plates l2 and l5 and receive the pins at opposite ends of a roller 55 whereby this roller is mounted for vertical movement relative l to the plates l2 and 135.

The web W is withdrawn from the roll R and .passed over the roller i5 under the roller 52 and over the roller lll and then to the printing couple comprising the cylinders A and B or other web feeding means in the machine with which my supporting device is associated. The roller 5@ therefore acts as a diabolo and forms a loop in the web intermediate the rollers l5 and All.

A stud 5l extends outwardly from the plate t2 and one end of an arm 52 is pivotally mounted on this stud. A motor 55 is vmounted at the other end of the arm 52 and a gear box 5G is associated therewith. A shaft 55 extends from the gear box 56 and a rollei` 55 is mounted thereon. The weight of the motor 52 and the gear box 56 holds the roller 55 in engagement with the periphery of the roll R and when the motor 55 is set in operation it rotates the roller 55 in such a direction that an unwinding movement is imparted to the roll R. lBy reason of the pivotal mounting of the arm 52 it may pivot inwardly and therefore the roller 55 will remain in engagement with the periphery of the roll R as the diameter of this roll decreases by reason of the withdrawal of the web therefrom.

As will be explained more fully hereinafter in connection with Fig. 12, the shaft 55 preferably has a worm wheel thereon that receives power from a worm gear on a shaft of the motor 55. By reason of such gearing the shaft 55 and therefore the roller 55 are prevented from turning in a reverse direction, and in view of this when the motor 55 is at rest and the roller 55 is in engagement with thg periphery of the roll R, this roller 55 serves as a brake on the roll R to prevent undesired unwinding of such roll.

When the device is initially set in operation the web is arranged in the manner shown in Fig. 13, that is to say, the diabolo 55 draws a substantial loop between the rollers l5 and lill. However, as soon as the cylinders A and B or other similar means start to operate the web is withdrawn from the loop between the rollers l5 and lll wherefore the roller or diabolo 55 moves upwardly, and when this loccurs circuit is f closed to the motor 53 and the roller 55 is set the hand nut 55 to lock the hand nut against 25 in operation to impart the unwinding movement to the roll R to cause an additional length of web to be unwound. This additional length of web is taken upby descent of the roller 50 and when this roller has descended in a predetermined amount circuit to the motor 53 is opened to stop operation of the roller 56. Thus when the loop in the web between the

rollers

44 and 41 decreases it is desirable to operate the roller 6I, and when the loop between said rollers increases it is desirable to interrupt operation of said roller.

To this end an arm 51 is mounted on the plate 42 adjacent the slot 46 and this arm has a cam surface 53 thereon engageable by the pin 56' on the roller 50 disposed in the slot 48. When the roller 50 moves upwardLv from a predetermined low position the cam surface 53 is engaged by the pin 68' whereupon the arm 51 is pivoted counterclockwise, as viewed in Fig. 13, movement of said arm in this 4direction being limited by a stop 53 on the plate 42. When the armI 51 moves in this direction, a lug 60 thereon engages the contact 6I and forces it into engagement with the contact 62 and this closes circuit to the motor 53, said contacts being in the circuit with said motor, as illustrated in Fig. 4. Hence as long as the roller 50 is out of a predetermined down or lowered position the contacts 6l and 62 remain closed and the motor 53 remains in operation, driving the' roller 56, but when a sufficient quantity of web has been unrolled from the roll R by the action of the roller 56 to permit the roller 50 to move into its predetermined down or lowered position, the pin 58' disengages cam surface 58 whereupon the lug 60 disengages the contact 6I and circuit to the motor 53 is opened and the action of the roller 56 is interrupted.

The cylinders A and B or other similar means in the machine always withdraw the web against the action of the roller 50 and therefore uniform tension is maintained on the web W which insures accurate feeding of the web by the cylinders A and B or other similar web feeding means in the machine. The roller 56 is operated to unwind the web from the roll R at a speed faster thanthe withdrawal of the web by the cylinders A yand B or other similar means, and this enables the roller 50 to effect its uniform tensioning action.

It is essential that the web be fed accurately to the cylinders A and B or other means and I therefore provide means for connecting my novel supporting device to the frame of the machine with which it is used whereby predeteri mined relation between the supporting device and machine may be maintained and therefore once accurate feeding of the web to the machine has been established it may be maintained. In

the present instance suitable brackets 63 and 64 are fast on the frame of the machine M andV a rod 65 is detachably connected thereto.

Blocks

66 and 61 are mounted on the rod 65. One end 4of a rod 68 is secured to the bar I0 and the other end of this rod is adjustably connected to the block 66. One end of another rod 69 is secured to the bar IB and the other end of this rod is adjustably connected to the block 61.

' The adjustable connections of the rods 68 and 6B to the blocks 66 and \1 enable adjustment of my supporting device relative to the frame of the machine M whereby feeding of the web W in a straight line between the cylinders A and B or other web withdrawing means in the machine may be established.

The plates 42 and 43 are adjustable on the bar Il so that they may be disposed in the proper position relative to the means in the machine to receive the web. The rollers carried by these plates are preferably of a width substantially equal to the width of the web and this promotes accurate feeding of the web. The adjustability of the roll R afforded by the hand nut 39 also promotes proper alignment of the web.

Rolls of varied width may be clamped on the axle 32 and the adiustability of the plates 42 and 43 permits these plates to be positioned soV as to receive rollers as 46, 41 and 50 of a length corresponding to the width of the web. The mounting of the rollers as 46, 41 and 50 facilitates installation and removal of these rollers which are changed each time a roll of different width is mounted on the axle 32.

The roll R is usually rather heavy but mounting thereof for rotative movement in my supporting device is facilitated inasmuch as the pawl 23 may be disengaged from thepinion 20 whereupon the shaft Il may be rotated so as to lower the blocks, as I6, into *a position such that the

arms

26 and 21 are disposed below the axle 32. Then the roll R may be rolled on its periphery into position to align the axle 32 and the bifurcation 40 with the

rollers

28 and 29 and 30 and 3|. Then the shaft Il may be rotated to elevate the blocks, as I6, which raises the roll R into proper position. The devices for so raising the roll R embody a substantial mechanical advantage wherefore the roll may be raised without substantial effort. When the roll R is in proper elevated position relative to the roller 56 the pawl 23 is again engaged with the teeth of the pinion 20 to lock the parts in position.

A modified form of my invention is illustrated in Figs. 1 to 9, the mechanism there shown being particularly adapted for use in a machine such as that shown in my above referred to application, Serial No. 221,841, but, of course, being susceptible of other usage. y

. The just referred to form of my invention includes a pair of elongated substantially L-shaped foot members as 10 which are provided at the lower end of the frame of the mechanism to provide a base, the foot members as 16 being interconnected by a tie rod 1l. A sleeve 12 is disposed about the tire rod 1I that extends between upstanding portions of the members as 10 and this sleeve and tie rod serve to maintain these members in properly spaced relation.

The frame 13 comprises two

uprights

14 and 15` which respectively extend upwardly from the members ask 10 and

side plates

16 and 11 are suitably secured at the upper ends of these uprights. These plates project forwardly and rearwardly of the uprights 14 and 15'and constitute the side frame members of the unit consisting of the web withdrawing and feeding means, sheet severing means, and the printing means associated therewith.

A support for a roll Ra of paper is so arranged that a roll may be expeditiously arranged in position to have a web Wa withdrawn therefrom. To this end a sleeve 18 is disposed about the sleeve 12 and is supported for rotating movement thereon. A pair of arms as 19 have the lower ends thereof slotted to pass about the sleeve .18, and these lower ends of these arms are welded or otherwise suitably joined to the sleeve 18. Thus the arms as 19 are supported for pivotal The ends vof the arms as 19 opposite those connected to the sleeve 1B are bifurcated as at B0 and as best shown in Fig. l rollers @l are mounted on each cf the arms as l@ near the bottom of the bifurcations therein and in such relation that a shaft 82 passed into the bifurcations will rest on these rollers to be rotatable thereon.

The arms as T19, therefore, adord a support for a roll Ra mounted on the shaft t2 and to dispose such a roll in web withdrawing position a crank @3, Fig. 2, is provided, the lower end of which crank d3 is fast to the outer end of a shaft itl journaled in the upright l5. The crank has a handle @5 at the upper end thereof 'in which a spring pressed plunger dit is mounted, the spring acting on this plunger to urge it toward the side plate ll. An opening dl, Fig. 2, is provided in the side plate lll and when the crank dit is in its operative position the inner end of the spring pressed plunger @t seats in the opening i371. An arm iid, Fig. 1, is fast to the inner end of the shaft @il and one end of a link @il is pivotally connected to the free end of the arm dil, the other end of this link d@ being pivotally connected to an arm l@ as indicated at dil. The length of the link tl@ is such that when theV plunger il@ is seated in the opening di! the roll support including the arms as l@ and shaft @2 is maintained in an upper operative position, which is to say, in a position to support the roll Ra clear of the oor or the like on which th members as il@ rest.

When a roll Rrr is to be introduced into the machine the plunger t@ is retracted from the opening ill! and the crank 513 is pivoted so as to lower the arms as '279. The shaft d2 will previously have been passed through the core 9i of the roll Ra and when the arms as 'i9 are in their lower position they lie well below the plane in which the shaft 82 will lie when passed through the core 9i. Therefore, the roll Ra may be rolled up into position to align the shaft d2 with the bifurcations as d@ in the arms as 'i9 and when this has been done the crank d3 is grasped and pivoted to its upper position, which is to say, the position in which the plunger at may enter the opening tl and in this pivotal movement the shaft d2 is caused to seat on the rollers as di and in the upward movement of the crank t3 the roll Ra is lifted clear of the floor to be supported for free rotation in the roll support when the plunger t@ is seated in the opening all.

The core 9i of the roll Ra in the present nstance is slidably supported on the shaft d2 and when the web Wa is withdrawn from the roll and passed to the web withdrawing means nolw to be described, the movement of the web through these devices causes the core of the roll to move axially along the shaft t2 until the roll Ra; attains its proper aligned position with respect to the web withdrawing and feeding means. This is quite an advantageous arrangement inasmuch as it avoids the necessity of providing devices for accurately aligning the roll Ra with the web withdrawing means.

The web withdrawing means are carried by

plates

92 and 93 with are respectively connected to the side plates 'le and ll in such a manner as to permit adjustment of the plates 92 and t3 along the plates it and 'lll to thereby vary the position of the web withdrawing means with respect to the web feeding means, described hereinafter, that is carried by the side plates l@ and lll. The plates 92 and @Si preferably fit close to the side edges of a web passed to the web withdrawing means, and to this end these plates are supported for adjustment transversely of the line of aaeaecc movement of the web, such support including a bar carried by the plates iti and lill, and the

plates

92 and 93 are fast to this bar by suitable clamping means as 95.

A shaft 95 is journaled in and extends between the plates 92 and @Si near the rear ends and upper edges thereof. A worm wheel til is fast to the shaft @t outwardly of the plate Q2 and meshes with a worm gear @t on the shaft of the motor @il that is mounted on the outer face of the plate 32. Closure of circuit to the motor 99 is under control of a switch arrangement to be described presently. The pitch of the teeth on the gear @il and the wheel @l is' such that movement can be imparted thereby only from the motor @9.

As best shown in Fig. 3, a discontinuous roller Hilti is fast on the shaft Qt, this roller being made discontinuous to enable the sections thereof to be adjusted along this shaft to be disposed in the positions which best effect withdrawal of a web from the roll Ra for the discontinuous roller lilil, when in rotation, serves to withdraw a web Wa from such roll Ra. In order to insure that the frictional contact of this roller with the web will be sufficient to insure such withdrawing, which is to say, to insure that the inertia of the roll Ra will be overcome when the roller it@ is rotating, it is preferable to provide one or more friction surfaces on the periphery of the roller tu@ and to this end rubber rings lill may be disposed about the periphery of the discontinuous roller at suitable intervals to have contact with the web and aord the desired frictional Contact between the web and the roller lull.

The rubber rings itil insure the presence of sumcient tension on the web that it is prevented from slipping rearwardly relative to the roller Mld, the pitch of the teeth on the worm gear @d and worm, wheel all insuring against rearward turning of the roller @@d, so that once the web is advanced it does not slip rearwardly.

Aligned slots m2 and it are provided in the plates @2 and 93, and a shaft ldd is mounted in these slots for vertical movement therein. A plurality of discs H65 are mounted at spaced intervals along the shaft it@ to aord adjustment upon variations in the width of the web. Still another shaft tu@ is journaled in the plates 92 and @il in horizontal alignment with the shaft @d but this shaft is mounted near the forward edge of the plates @2 and 93. This shaft carries liscs lill! similar to the discs tu@ on the shaft As the web is withdrawn from the roll Ra it is passed over the discontinuous roller lil@ and under the roller aorded by the discs U35 and then over the roller aorded by the discs it?! on the shaft ifi@ so that the roller afforded by the discs ltl forms a loop in the web intermediate the roller it@ and the discs lull.

The web Wa passes from the just described web withdrawing and looping means to the web feeding means which include a shaft tilt journaled in the plates i6 and lll and which has a pulley lil@ rotatably mountedthereon outwardly of the plate lid. A belt ddii, Fig. l, is passed about the pulley ida to a suitable source of power (not shown) which operates to constantly rotate the pulley its. A belt tightener lil, Fig. l, acts on a pass of the belt il@ between the pulley lil@ and the source of power.

The pulley lua is part of a clutch, such as is disclosed in my cc-pending application, Serial No. 239,561, nled November 8, 1938. 'lllns clutch also includes a fixed part H2 that is fast on the shaft |08. and a slidable part H8 which is constantly connected to the fixed part I I2 and which has clutch teeth th .'eon engageable with clutch teeth on the hub of the pulley |08, springs acting between the fixed part H2 and the slidable part H3 to urge the clutch teeth on the part H8 toward the clutch teeth on the hub of the pulley |09. A pin H4, Fig. 1, extends from the periphery of the part H3 and, when the clutch is disengaged, this pin is engaged with a cam surface on the plate H5. The plate H5 is pivotally mounted, as indicated at H6, and a spring H1 acts thereon to urge it toward the periphery of the part H3. A solenoid H8 is supported on the plate 16 and includes a core H9 to which a plate |20 is pivotally connected, the plate |20 including a shoulder |2| that is adapted to seat under the free end of the plate H5.

When the solenoid H8 is energized in a manner to be explained hereinafter the core H9 thereof is attracted upwardly whereupon the plate |20 moves upwardly to retract the cam surface on the plate H5 from engagement with the pin ||4 whereupon the clutch teeth on the part H8 engage the clutch teeth on the hubof the pulley |09 to thereby connect the pulley |09 to the'shaft |08 and thereupon the shaft |08 starts to rotate. The pin H4, soon after the shaft |08 starts to rotate with the pulley |09, pivots the plate |20 from engagement with the plate H5 whereupon the spring H1 returns this plate into engagement with the periphery of the part H3 so that near the end of the revolution initiated by energization of the solenoid H8 the pin H4 will reengage the cam surface on the plate H5 and disconnect the clutch teeth on the part H3 from the clutch teeth on the hub of the pulley |09. It will therefore be apparent that the shaft |08 makes but a single revolution each time the solenoid |8 is energized to set this shaft in rotation. It is rotation of the shaft |08 that causes the web Wa to be advanced past the severing means, to be described presently. The web feeding means is affordedby a segmental feeding roller |22, Fig. 5, that is fast to the shaft |08, the roller |22 being provided with a fiat diametrically extending face |23 toward which a face of a clamping block |24 is disposed, the face |23 being recessed, as well as the cooperating face of the block |24, to fit about the shaft |08. Clamp bolts |25 freely pass through the block |24 and are threaded into the roller |22 and serve to clamp the roller |22 and in this way an adjustable connection of the roller to the shaft is afforded for a purpose to be made apparent presently.

Inasmuch as the shafts |08 and '|26 rotate synchronously it is possible to so adjust the rollers |22 and |29 with respect to each other that the leading edges thereof will move into cooperating relation to clamp the web therebetween during but a selected portion of the rotation of the shafts |08 and |26 for the web is advanced or fed only when the peripheries of the rollers |22 75 and |29 are rolling over each other with the web clamped therebetween. The length of `this rolling engagement of these two rollers with the web determines the amount of web that will be fed during a single rotation of the shaft |08 and therefore determines the amount of web fed past the severing means.

Each time the shaft |08 is set in operation to feed a portion of the web past the severing means, the web is withdrawn by the rollers |22 and |29 from the loop created by the discs |05 on the shaft |04 and therefore the actual web feeding means, which is to say, the rollers |22 and |29, need not overcome the inertia of the roll Ra and consequently the likelihood of slippage which might be attendant to direct withdrawal of the web Wa from the roll Ra by the feed rollers |22 and |29 is overcome, which, as will be explained, insures accurate feeding of the web beyond the severing means and accurate sizing of the sheets severed from the web. However, each time the rollers |22 and |29 act to withdraw the web from the loop formed therein by the discs |05 on the shaft |04, this loop is reduced in size. Hence, to insure that an ample supply of web will always be present in the loop, means are provided under control of the shaft |04 for setting the motor 99 in operation to effect withdrawal of the web Wa from the roll Ra.

In the present instance such means includes a pivotally mounted lever |30, Figs. 1 and 7, which carries a pin |3| of insulating material that bears on the blade |32 of a switch |33 and which carries a contact that is engageable with a contact on the other blade |34, of this switch. The blades |32 and |34 are suitably supported on a block |35 of insulating material mounted on the outer face of the plate 92. The contacts on the blades |32 and |34 are in circuit with the motor 99 and whenever these contacts are engaged circuit is closed to the motor to set it in operation. Whenever the motor 99 is in operation the discontinuous roller |00 acts to withdraw the web Wa from the roll Ra, and the web so withdrawn is fed into the loop created by the discs |05. As soon as this loop attains a predetermined size the shaft |04 disengages the cam surface on the lever |30 with which it cooperates and thereupon the pin |3| moves away from the blade |32 to disengage the contacts on the blades |32 and |34 ywhich opens circuit to the motor 99 and thereupon withdrawal of the web Wa from the roll Ra is interrupted. y

The severing means to which reference has been made includes a movable knife |36 and a. stationary cooperating cutting member |31 on the bar |38, which bar extends between the

side plates

16 and 11 forwardly of the shaft |08. It is essential that there be a shear action between the movable knife |36 and the stationary cooperating cutting member |31 and this is attained first of all by tapering the cutting edges of the knife |36 inwardly and upwardly from the outer edges thereof, as shown best in Fig. 2. Moreover, this enables the outer ends of the knife |36 to serve as a stop to maintain the knife |36 and member |31 in cooperating relation under the influence of the spring |39 that urges the knife |36 toward the member |31. The knife |36 consists of a thin strip, preferably of saw steel, and to further augment the shear action above referred to this knife |36 is secured to the concave forwardly disposed face of a bar |40 by screws 94 or the like as in Fig. 8 and the knife |36 therefore assumes the configuration of this concave face. Inasmuch the cutting edge on the stationary co operating cutting member itil is straight it will be apparent that the shear action of the inclined edges of the knife i8@ is augmented by the movenient of the cencavooonven knife over ythe straight cutting edge on the vmember lill] and I hence a neat shearing action results. This construction has several advantages for it enables the knife to be made in one piece and thereby elim'iates the necessity of accurately aligning twoverent sections, and it also insures permanent and accurate alignment of the movable hnife blade with the stationary cutting edge and avoids the necessity of making fine adjustments.

The bar ld@ is connected at its ends with up= standing arms Hdl and M2 which, at their lower ends, are pivotally connected to, and carried by, linlrs M3 and [Idd which have their forward ends respectively pivotally connected to the side plates l@ and lll. lfirms as M5 are fast to the shaft it@ near opposite ends thereof, and these arms respectively carry rollers as it which, in the course of rotation of the shaft tilt, engage the links idd and Mld, that are urged toward the shaft itt by springs as llll, to pivot the inner ends of these linlrs downwardly whereupon the movable knife it@ is moved into cooperating relation with a stationary cutting edge [Jill to sever the sheet. The arms as i635 are so positioned on the shaft itil that the rollers as id@ thereon engage the links i133 and idd after the sheet has been fed past the knife i3@ by the cooperation of the rollers i122 and H29.

llt is necessary that the web be tightly clamped during the severing operation and during at least part of the time the rollers i222 and G29 are disengaged therefrom so as to prevent the web from undesirably slipping rearwardly. To this end a clamping bar id@ is provided above the member titl.. clamping bar id@ is carried by bolts as tdt) that have the lower ends thereof naedly connected to the clamping bar Mil, but which bolts are freely passed through the lrnife bar ldd. Springs, as itil), are disposed about the bolts id@ between the bars id@ and, tdt. During the time the web is being fed iorwardly by the rollers H22 and it@ the bar 'ldd is in the position shown in t, but, as will he explained presently, shortly after the rollers 22 and i2@ disengage the web the rollers as i136 on the arms as tdt engage the linlrs M-3 and idd whereupon the bar lll@ starts to move downwardly and this causes the clamping bar lidi? to tightly clamp the web against the member till during continued downward movement of the bar idd. During the severing f,

operation the springs as l5@ are compressed and exert effective force on the bar ldd to insure against rearward slippage of the web. IThe bar lili? remains in the aforesaid clamping engage-- ment with the web until the rollers 022 and i229 have again clamped the web therebetween but by the time these rollers have imparted any niaterial advancing to the web, the clamping bar will be retracted from the clamping position shown in me. 9 into the free position shown in Fig. f3.

Prior to the time that part of thevweb extended beyond the knife i136 is clamped by the bar. M8, this portion of the web is clamped by a clamping nger 65H, Fig. 5, which projects through anv opening G52 in the bed plate U53. A guide bar ld is provided on the upper surface of the bed plate H53 and aords one side of a guideway G through which sheets severed from a web are that is aligned with the knife i8@ serves as an abutment for the end of the web when it is fed forwardly beyond said knife. Moreover, the bar 65d is spaced from the knife it@ in the amount desired for the width of the sheet S, for a pur pose to be explained presently. The clamping finger itl is mounted adjacent the bar ltd and is carried by a bar tijd which has a pin l5@ passed through an openingv in the forward end thereof, said opening neatly ntting about said pin. ll. spring itil between the head of the pin and the bar G55 tightly urges the bar into engagement with a cross bar l5@ that extends between the side plates it and lill. A cam it@ is fast on the shaft itt and the free end of the bar itt emends beneath this cam. Subsequent to the time the end of the web engages the bar itil a rise on the cam i engages the bar itil and pivots it downwardly to thereby engage the finger itil with that portion of the web that is extended beyond the lniife wherefore this portion of the web is tightly clamped against the bottom of the sheet guideway G and held against displacement from the bar ld.

it is of course advantageous to feed the web and sever the sheet rapidly and to this end the various mechanisms entering into this are timed to operate in close relation, as will now be explained, reference being made to the timing chart, Fig. d.

it the point itil, Fig. d, the solenoid il@ will have been energized and the clutch under control thereof will have been engaged so that the shaft it@ will at the point it@ start rotating. At this time the rollers H22 and l2@ will be in clamping engagement with the web and therefore at the point it@ the web will start to feed forwardly beyond the knife it@ and this feeding movement continues until the point itl is attained at which point the rollers 522 and l2@ disengage the web. However, it will be noted that prior to the time the point iti is attained and by the time the point it is attained the rise on the cam i5@ will have engaged the bar i5?) so that at the point it?! the nger tt will be clamping the sheet in the manner above described.

it will be noted that the finger 115i in clamping the sheet at the point itt does so prior to the time the rollers H22 and l2@ have disengaged the web and interrupted feed thereof at the point itil with the result that between the points itt and it] the feed of the web will be continued notwithstanding the clamping thereof by the linger iti. The result of this is that the web buckles because the end thereof is, by this time, engaged with the bar ltd, and in each feeding operation the rollers i122 and l2@ act to advance past the knife itt more web than is required to aord a sheet of the desired width. This avoids the necessity of causing the rollers H22 and in each operation thereof to feed the precise width of sheet required. Thus, when the feed of the web is interrupted at the point itl by reason of the disengagement of the rollers i222 and i129 therefrom, the web is freed to the action of the looper adorded by the shaft ltd and the discs Miti thereon so that between the point l and the point it@ this looper pulls the web rearwardly and renders it taut between the discs itt and the clamping finger ihwhich finger prevents the end of the web from disengaging the bar ltd. `'.'ihe leading edge of the web will be, therefore, engaged with the abutment adapted to be passed. That part of the bar [ltd if@ adorded by the bar itil and since this bar is cutting edge on the member |31 the precise width of the desired sheet and, further, since the web will by this time be taut, it is clear that the precise desired width of the sheet is disposed beyond the knife |36 and the cooperating stationary cutting edge.

Therefore, at this time when the desired width of sheet is disposed beyond the knife |36, this knife may and does start to move toward its cooperating stationary cutting edge and this is initiated at the point |61. Hence, the bar |40 will start to move downwardly at the point |61, and at the point |68 the bar |48 will attain the position shown in Fig. 9, which is to say, clamping engagement with the web. This occurs prior to the time the knife |36 actually starts severing the sheet so that the sheet is firmly clamped along its leading edge by the finger and it is also clamped rearwardly of the knife by the bar |48 and in this way the sheet is firmly held during the severing operation which begins shortly after the sheet is so held.

By the time the point is attained the severing operation of the knife |36 is completed and the sheet has been severed from the web. The shaft |08 is still rotating and at the point |1| the rollers |22 and |29 move back into engagement with the web Wa and clamp it therebetween so that since the web is now again clamped by the rollers |22 and |29 the clamping effected by the bar |48 may now be released and this occurs at the point |12. Thereafter the point |60 is re-attained so that the parts are in position to start a new cycle of operation.

Upon its severance from the web Wa at point |10, the sheet S is free to drop into a collector, in the event that no more machine oper.- tions are to be performed on it. If additional machine operations, such as printing, are to be performed on the sheet S, suitable sheet feeding means can be provided to move the sheet away from the station at which it was severed, such sheet feeding means becoming operative, say, at point 13. In this event it will be recognized that the sheet is completely severed from the web prior to the time the feeding means therefor become operative and in view of this it is of course essential that the sheet be prevented from catching on the knife 36 at the time it is to be fed forwardly, for the knife will be in its lower position at the time the sheet is fed away, and this is accomplished in the following manner.

As best shown in Figs. 1 and 5, the bed plate |53 is terminated along the line |14 in spaced relation with the knife |36 and its cooperating stationary cutting member |31. The cutting edge of the cutting member |31, as best shown in Fig. 5, lies in a horizontal plane slightly above the top plane of the bed plate |53. 'It will also be remembered that the knife |36 is bowed longitudinally so that the ends thereof project forwardly of the medial portion thereof. However, it is the ends of the sheet that are severed first, the medial portion being severed as the final step in the severing operation.

Now bearing in mind thatit is essential that the sheet be free to the action of the sheet feeding means, to be described, it is desirable to bend the sheet away from the knife 89 and it is because of this that the bed plate |08 is terminated along the line |25 as explained above.

However, when the web is fed forwardly to engage the leading edge thereof with the bar |09, most of the part of the web that is to afford the sheet is disposed upon the bed plate |00 but the rear portion thereof .overhangs the termination of the bed plate |08 along the line |25. It is this portion of the sheet, when it is severed from the web, that is bent down away from the knife 09 in a manner now to be described.

The operation of the plate |15 is as follows. In the course of downward movement of the knife |36 the lower edge of the plate |15 comes into engagement with the sheet being severed from the web, this plate so engaging the sheet prior to the time the knife |36 has attained its lowermost position. The plate cornes to rest as soon as it engages the sheet but movement of the knife of course continues and during this continued movement the pin |16 moves through the slot |11. When, however, the severing of the sheet from the web is completed, no support is afforded for that portion of the sheet extending beyond the point of termination of the bed plate |53 along the line |14, and the weight of the plate |15 is then impressed on the sheet and this will be sufficient to bend the sheet down away from the knife |36 particularly in view of the fact that the cutting edge of the stationary cutting member |31 lies in a horizontal plane above the top plane of the bed plate |53. Therefore, the sheet is bent down away from the knife |36 and all portions thereof'are clear of the knife prior to the time the sheet feeding means start to move the sheet away from the position which it occupies upon severance thereof from the web.

The timing of the operation is such that the sheet starts to move, say, at point |13 prior to the time the knife |36 has moved upwardly under the influence of the spring |41 suiliciently to disengage the plate 15 from the sheet. In any event, however, the leading marginal portion of the sheet will always be beyond the left-hand end of the knife as it is viewed in Fig. 2 prior to the time the plate |15 disengages the sheet. The foregoing arrangement therefore enables the sheet to be fed prior to the time the knife |36 has attained its uppermost position for it is obvious that if feeding of the sheet awaited the knife |36 attaining its uppermost position the knife at this time` would be entirely out of the path of movement of the sheet and hence could not interfere with advancing thereof and in such an event the just described devices could be eliminated. To await the knife |36 attaining its upper position is undesirable, however, for so to do would slow down the operative speed of the machine.

The sheet feeding means hereinabove referred to and which is rendered effective at the point |13, as just described, includes a roller |19 on the shaft of a motor |3| carried by the arm H32 that is mounted as indicated at iti] on the bed plate H53. A pin HB on the collar it that is fast to the shaft itu acts on a pad it on the arm itt, that is fast to the frame of the motor itl, just prior to the time the aforesaid point llt is attained to raise the motor i3! and therefore the roller i119 which thereupon extends through the bed plate 53 and cooperates with a roller i719' to clamp the severed sheet between the rollers. Since the motor iti is con. stantly rotating the roller i719, such clamping of the severed sheet causes it to be fed through the sheet guideway G to a point of use, such as a printing position or the like along the sheet guidew-ay, the roller il@ starting to so feed such severed sheet at the aforesaid point i773 and causing the sheet to be fed in a direction that is in right angular relation with the line of alliance of the web.

The form of the invention shown in Figs. to 12 is similar to that shown in Figs. 1 to 9 except that means similar to that employed in the form of the invention shown in Figs. 13 to 16 are utilized to withdraw the web from the roll in place of the motor 99 and associated parts. In view of such similarity of mechanism, the parts shown in Figs. 10 to l2 which correspond to parts already described are indicated by the same reference character except that the suffix b is added to the reference character Where it appears in `Eigs. i0 to 12.

Heretofore reference has been made to Fig. 12 and by referring thereto it will be seen that a worm gear iti is fast on 'the shaft it@ of the motor 531) and that this worm gear meshes with a worm wheel itt fast on the shaft 55o. The pitch of the meshing teeth on the worm gear iti and the worm Wheel it@ is such that the worm wheel Wedges rather than drives the worm gear and it is this that prevents the roller 56h from rotating reversely wherefore, when the motor 53h is at rest, the roller 5th acts as a brake to prevent undesired unwinding of the roll Rh.

1t will be manifest from the foregoing description that have provided an arrangement which maintains uniform tension on a web so as to insure accurate feeding thereof, this being further insured by avoiding 'the necessity of the Web withdrawing overcoming the inertia of the roll from which the web is withdrawn. This iatter is accomplished by imparting movement to the roll from which the web is withdrawn at a rate more rapid than the utilization of the web and according to my invention excessive withdrawal of the web is avoided even where the utilization of the web is intermittent.

`Furthermore, my invention facilitates positioning the roll from which a web is to be .withdrawn in position where the web can be withdrawn therefrom; it insures accurate feed of the web and prevents tearing or wrinkling of the web; and devices that may be used with my invention insure neat the accurate division of the web into sheets.

Thus, while 1 have illustrated and described selected embodiments of my invention it is to be understood that these are capable of variation and Inodication and I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

1 claim:

1. In a device of the class described, means supporting a roll of paper or the like for unaaeaeeo winding `movement whereby a web withdrawn therefrom may be supplied to a machine or the like wherein operations are perfumed on the web, means for imparting unwinding movement to the roll, a pair of rollers mounted in spaced apart relation and having a web passed thereover, another roller mounted intermediate said spaced apart rollers and having the web passed thereunder whereby the intermediate roller may form a loop in the web intermediate said spaced apart rollers, the last-named roller having an extension thereon, supporting means in which said rollers aremounted, and control means including a pivotally mounted arm having acam surface thereon and normally spaced resilient contacts, said arm and said contacts being mounted on said supporting means, said contacts being positioned relative to said arm and the cam surface thereon to be urged into engagement With each other upon cooperation of said extension with said cam surface when the loop in the web is diminished in a predetermined amount to thereby set in operation the means for imparting unwinding movement to the roll whereby the magnitude of the loop formed in the web may be increased, said extension cooperating with said cam surface to enable separation of said contacts when the loop in the web attains a predetermined size.

2. In a device of the class described, means supporting a roll of paper or the like for unwinding movement whereby a web withdrawn therefrom may be supplied to a machine or the like wherein operations are performed on the web, electrically operated means swingingly mounted upon said supporting means for imparting unwinding movement to the roll, a roller looping the web and applying tension thereon as it passes to the machine, guiding means for said roller, and control means mounted on the guiding means and engageable by said roller and including a pair of contacts in circuit with said electrically operated means, said roller acting on the control means to close said contacts to set said electrically operated means in operation when the loop formed in the web by said roller is diminished in a predetermined amount, said roller also acting on the control means to effect separation of said contacts and interruption of operation of the electrically operated means when said roller forms a loop in the web of predetermined size whereby the magnitude of the loop formed in the web by said roller may be maintained within predetermined limits.

3. 'in a device of the class described, means supporting a roll of paper or the like for unwindng movement whereby a web withdrawn therefrom may be supplied to a machine wherein operations are performed on the web, electrically operated means for imparting unwinding movement to the roll, a pair of rollers mounted in spaced apart relation and having a web passed thereover, another roller mounted intermediate said spaced apart rollers and having the web passed thereunder whereby the intermediate roller may form a loop in the web intermediate said spaced apart rollers, supporting means in which said rollers are mounted, control means mounted on said supporting means and positioned to be acted on bythe intermediate roller to regulate operation of the means imparting unwinding movement to the roll whereby the magnitude of the loop formed in the web may be maintained within predetermined limits, the control means including a rockably mounted arm having a cam surface thereon that is acted on by the intermediate roller. and a pair of normally spaced resilient contacts in circuitl with said electrically operated means, the intermediate roller acting on the cam surface on said arm to move said contacts into engagement with each other when the loop formed in the web by the intermediate roller is diminished in a predetermined amount and to open said contacts when the loop formed in the web by the intermediate roller attains a predetermined size whereby the magnitude of the loop formed in th'e web may be maintained within predetermined limits.

4. In a device of the class described, means supporting a roll of paper or the like for unwinding movement whereby a web withdrawn therefrom may be supplied to a machine or the like wherein operations are performed on the web, electrically operated means for imparting vunwinding movement to the roll, a roller for looping the web and applying tension thereon as it passes to the machine, guiding means for said roller, an arm means mounted on the guiding means and having a cam surface thereon engageable by said roller, a pair of contacts in circuit with said electrically operated means and under control of said arm and operable to interrupt operation of the means imparting unwinding movement to the roll when said roller forms a loop of predetermined size in the web and also operable to set the means for imparting unwinding movement to the web when the loop formed therein by said roller is reduced in a predetermined amount, the means for imparting unwinding movement to the web including as part of the driving means thereof aworm gear and a worm wheel, said gear and Wheel having the pitch of the teeth thereof formed to prevent rearward movement of the member of the unwinding movement imparting means that engages the web so as to prevent rearward movement of the web when the means for imparting unwinding movement are at rest, and means on the member engaging the web for insuring `good frictional engagement thereof with the web.

5. In a device of the class described, means supporting a roll of paper or the like for unwinding movement whereby a web withdrawn therefrom may be supplied to a machine or the like wherein operations are performed on the web, an arm pendulously mounted on the supporting means and depending therefrom and movable as a pendulum relative thereto, an electric motor mounted at the free end of said arm, and a roller carried by said arm and driven by said motor and engageable with the periphery vof the roll to impart unwinding movement to the roll, said arm being of such a length that the pendulous mounting of said arm enabling said roller to remain in engagement with the periphery of the roll as the diameter of the roll decreases as the web is withdrawn therefrom and until the roil is completely used.

6. In a device of the class described, a supporting frame including a pair of spaced and vertically extending guide plates each having a guide slot formed therein, a pair of web-guiding rollers carried by said guide plates and a web-tensioning roller arranged between said guide rollers and having a projecting portion at each end thereof and said projecting portions extending into said guide slots, a member pendulously mounted upon said supporting vframe and depending therefrom and adapted to move as a pendulum relative thereto, a member rotatably mounted upon the lower end portion of said pendulum member and adapted to engage a roll of paper or the like carried by said supporting frame for imparting unwinding movement thereto, means carried by said pendulum member for operating said rotatably mounted member, and means actuated by one of the said projecting portions for controlling the operation of said operating means.

`'1. In a device of the class described, a. supporting frame including a pair of spaced and vertically extending guide plates each having a guide slot formed therein, a pair of web-guiding rollers carried by said guide plates and -a web-tensioning roller arranged between said guide rollers and having a projecting portion at each end thereof and said projecting portions extending into said guide slots, a member pendulously mounted upon said supporting frame and depending therefrom and adapted to move as a pendulum relative thereto, a member rotatably mounted upon the lower end portion of said pendulum member and adapted to engage a roll of paper or the like carried by said supporting frame for imparting unwinding movement thereto, means including an electric motor carried by said pendulum member for operating said rotatably mounted member, and means actuated by one of said projecting portions for controlling the operation of said electric motor.

8. In a device of the class described, a supporting frame including a pair of spaced and vertically extending guide plates each having a guide slot formed therein, a pair of Web-guiding rollers carried by said guide plates and la webtensioning roller arranged between said guide rollers and having a projecting portion at each end thereof and said projecting portions extending into said guide slots, a member pendulously mounted upon said supporting frame and depending therefrom and adapted to move as a pendulum relative thereto, a member rotatably mounted upon the lower end portion of said pendulum member and adapted to engage a roll of paper or the like carried by said supporting frame for imparting unwinding movement thereto, means including an electric motor carried by said pendulum member for operating said rotatably mounted member, and means actuated by one of said projecting portions for controlling the operation of said electric motor, said last-named and motor controlling means including a pair of normally spaced resilient contacts in circuit with said motor, and a member pivotally mounted upon one of said guide plates and adapted to move said contacts into engagement with each other so as to close circuit to said motor.

9. In a device of the class described, means supporting a roll of paper or the like for un- Winding movement wheneby a Web withdrawn therefrom may be supplied to a machine or the like wherein operations are performed on the web, an arm pendulously mounted on the supporting means and depending therefrom and movable as a pendulum relative thereto, an electric motor mounted at the free end of said arm, a roller carried by said arm and driven by said motor and engageable with the periphery of the roll to impart unwinding movement to the roll,

the pendulous mounting ci said arm enabling said roller to remain in engagement with the periphery of the roll as the diameter oi' the roll decreases as the web is withdrawn therefrom, means for looping the web and applying tension thereon as it passes to the machine or the lllrey guiding means ior the looping means, and con t the looping means moving out oi effective or circuit-closing position relative to said contacts and permitting separation oi said contacts and interruption oi operation of said motor when the looping means forms a loop in the web oi pre determined size whereby the magnitude of the loop :formed in the web by the looping means may be maintained within predetermined limits.

lll. En a device oi the class described, means supporting a roll oi paper or the like for unwinding movement whereby a web withdrawn therefrom may be supplied to amachine or the like wherein operations are performed on the web, an arm pendulously mounted on the supporting means and depending therefrom and movable as a pendulum relative thereto,7 an electric motor mounted at the free end of said arm, a roller carried by said arm and driven by said motor and engageable with the periphery of the roll to impart unwlnding movement to the roll. the pendulous mounting of said arm enabling said roller to remain in engagement with the periphery of the roll as the diameter of the roll decreases as the web is withdrawn therefrom, means for looping the web and applying tension thereon as it passes to the machine or the like, guiding means for the looping means, control means mounted on the guiding means and engageable by the looping means and including a pair of normally spaced resilient contacts in circuit with said motor, the looping means act ing on the control means to close said contacts iti to set said motor in operation to drive said roller when the loop formed in the web by the looping means is diminished in a predetermined amount, the looping means moving out of esective or circuit-.closing position relative to said contacts and permitting separation of said contacts and interruption ci operation of said motor when the looping means forms a loop in the web of predetermined size whereby the magnitude of the loop formed in the web by the loopu ing means may be maintained within predeter= mined limits, and driving means intermediate said motor and said roller operative to impart rotation to said roller from said motor and to hold said roller against rotation when said motor is at rest whereby when the motor is at rest said roller acts as a brake to prevent movement of the roll oi paper.

ll. In a device of the class described, means supporting` a roll of paper or the like for unwinding movement whereby a web withdrawn therefrom may be supplied to a machine or the like wherein operations are performed on the web, a pair of rollers mounted in spaced apart relation and having the web passed thereover, another roller mounted intermediate said spaced apart rollers and having the web passed thereunder whereby the intermediate roller may form a loop in the web intermediate said spaced apart rollers, supporting means in which said rollers are mounted, an electric motor on said supporting means operative to drive the one oi said spaced apart rollers over which the web is rst passed to thereby withdraw the web from. the roll into the loop formed therein, and control means including normally spaced resilient contacts mounted on said supporting means and p0- sitioned to be urged into engagement with each other by the intermediate roller to close circuit to said motor to impart unwinding movement to the roll when the loop in the roll decreases in size and adapted to separate when the loop increases n size whereby the magnitude of the loop formed in the web may be maintained within predetermined limits.

WAL'I'ER T. GOLLWITZER.