US2232317A - Winder drive - Google Patents

Description

Feb. 18, 1941.

J. K DouGLAs WINDER DRIVE Filed July s, 1939 t A, INVENTOR. JAMES K. Dalmau/m BY I M W Y ATTORNEY.

Fb. 18, 1941. J, K DOUGLAS 2,232,317

WINDER DRIVE Fiied "July s, 1959 s shQets-sneet 2 BY .2 ATTORNEY.

` Feb. '1*8,` 1941.

J. K. DQyGLAs 6 Sheets-SheetI 4 mW lEnLEor m nl afl.. v Y mw f E w ew w QT y mm. mw w ww .mmh E w .01W Nv. Rw mm v u v2 v@ L h@ u A .Q Y ww WN MMM E8 y A .R t ,IL wk S M E." mi kn n ms mm2 mw Fel).v 18, 1941. J; K DOUGLAS 2,232,317

wINDER DIvE Filed July 3, 1939 v 6 Sheets-Sheet 5 INVENToR. JAMES K.D|:1UGLAS BY Wma/PM m ATTORNEY.

J. K. DOUGLAS WINDER DRIVE Filed July 5, 1939 6 Sheets-Sheet 6 m@ QVT/ INVENToR.

JAMES K. DDUBLAS M ATTORNEY.

/TW` .lar

.NN .DE

Patented \Feb. 18, 194.1

UNITED STATES- PATENT vOEI-mE vThe Oilgear Company, poration of Wisconsin Milwaukee, Wis., a cor- Application July 3, 1939, serial No. 282,649

22 Claims.

This invention relates to drives of the type employed to drive a Winder which winds sheet material into rolls, and it relates in particular to a hydraulic Adrive which includes a rotary hydraulic motor for driving the winding `shaft or drum on which the material is wound, a pump for supplying liquid tothe motor to energize it, and means for varying the relative displacements of the pump and the motor to thereby decrease the speed of the Win-ding shaft or drum as the roll of material thereon increases in diameter.

In winding sheet material into a roll as i-t is delivered by a machine, it.is essential that the sheet be kept undertension in order to prevent it from wrinkling or buckling and in order to -form a roll of the desired density, and it is very often essential that the tension on the sheet be varied in response to a variation in the linear speed of the sheet or in response to the roll increasing in diameter or to both of these factors. .The present invention has as an object to provide a drive of the above character with means for enabling it to keep the tension on the sheet within closer ,limits than was heretofore possible.

Another object isv to provide a hydraulic winder drive with means for compensatinglfor the friction of the winding machine friction of the Winder motor.

Another object is to -provide a hydraulic Winder drive with means for varying the tension on the sheet in response toa variation in the linear speed of the sheet.

Another object is to provide a hydraulic Winder drive with means for varying the tension on the sheet in response to the sheet accumulating upon the winding shaft.

Another object is to provide a hydraulic Winder drive with means' for increasing thetorque of the motor during acceleration of thek sheet.

Other objects and advantages will appear from the description hereinafter given of Winder drives in which the invention is embodied.

According to the invention in its general aspect and as ordinarily embodied in practice, the Winder drive includes a variable displacement rotary hydraulic motor for driving the Winder, a rst pump which discharges liquid at a rate proportional to the speed at which the sheet is delivered to the winding shaft, a second pu'mp which discharges liquid at a constant rate, pressure chan. nels for directing liquid from both pumps to the motor to energize it, a tension control'valve which maintains pressure in the pressure channels and permits the escape therefrom of the liquid discharged by the pumps in excess of the liquid required to drive the motor, return channels connecting thev outlet of the motor to the intake of the'iirst .pump whereby rate at which the motor can discharge liquid,

and the internal that pump meters the v. outflow from the motor and thereby governsthe and means responsive to variations in the pressure in the return channel for varying the ,dis"

placement of the motor whereby the motor displacement is increased with a'resultant increase in motor torque and decrease in motor speed as the roll of material on the winding shaft increases in diameter.

The invention further provides means for ex-j tracting liquid at a limited rate from the return channel to therebyv increase the motor displacement sufciently to compensate for the friction in the winding machine and in the motor, means' for adjusting the tension control valve to cause a greater pressure to .be created in the pressure channels and thereby enable the motor to exert a greater torque when accelerating the winding machine, means for adjusting the tension control valve in response to a. variation in the linear speed of the sheet, and means for adjusting the tension controlvalve as the roll of material on the winding shaft increases in diameter.

The invention is exemplied by the Winder drives shown schematically in the accompanying drawings in which the views are as follows:

, Fig. 1 is 1n part a diagrammatic view showing the invention embodied in a drive, which is employed to drive a machine tially continuous sheet of ilexible material into a roll as fast as it is delivered by another machine, and in part a diagram of the'hydraulic circuit of the drive, the several parts being shown in the positions occupied When the drive is idle andthe drive being shown provided with a throttle valve the function of which is to cause the drive to vary the tension on the sheet in response to a variation in speed.

for winding a substan- Fig. 2 is a view showing a control valve in the Fig. 4 is a view showing 'the drive provided,

With aA valve which may be used instead of the throttle valve shown in Fig. l, only a part of the circuit being shown as the drive is otherwise the same as the drive shown in Fig. 1.

` Fig. 5 is a view similar to Fig. l but showing a resistance valve substituted for the throttle valve in order that the tension on the sheet may be varied in response to the roll increasing in diameter.

iFig. B is a view showing a method dierent from that shown in Fig. 5 for varying the tension on the sheet in response to the roll increasing in diameter, only a part of the drive being lshown as. the remainder is substantially the same as. shown in Fig. l.

Fig. '7 ls a view similar to Fig. 6 but showing the drive provided'with means for varying the tension on the sheet in response both to varia.- tions in speedvand variations in roll diameter.

Fig. 11 is a section takenron a. line I III of' Fig. 10.

Fig. 12 is a top plan view of the parts shown in Fig. 11. Fig. 13 is a section taken on a line I3-I3 of Fig. 11'.

For the purpose of illustration, the invention has been shown applied to a Winder for winding paper into rolls as it is delivered by a machine but itis to be understood that the invention is not limited to such use as it is 'susceptible of wide application. f

Figs. 1 to 3 Since the Winder andthe paper delivering machine form no part of the present invention,

the Winder has been represented by a winding shaft I on which a substantially continuous strip of paper 2 is wound into a roll 3 as it is delivered by a machine 4 which has been represented by a stand of rollers.

Machine 4 is connected to a prime mover (not shown) through a suitable drive 5 8 and a transj mission 1 having a lever 8 to control it. When lever 8 is in the position shown in fulll lines, transmission 1 is in neutral and machine 4 will be idle. When lever 8 is shifted to the position shown in dotted lines, transmission 1 will-trans1 mit motion, from the prime mover through drive to be moved in one direction by a piston I2 con- 5-6 to machine 4 to drive it.V The speed of machine 4 may be varied between zero and maximum in any suitable manner as by varying the speed of the prime mover.

Shaft I is connected by a suitable drive 9 Ato a` variable displacement hydraulic motor I8 which may be of any suitable type. As shown, motor I0 is provided with a displacement varying member or slide block Ii which is adapted nected thereto and fitted in a stationary cylinder I3 and is adapted to be moved in the other direction by a piston I4 connected thereto and fitted in a stationary cylinder I5.

Liquid for engizing motor I8 is supplied thereto from two pumps I8 and I1 through a branched pressure channel I8 which connects the outlets of both pumps to the inlet of motor I8. Pump I6 is drivenfrom a power source not shown atl a substantially constant speed when'the drive is *n operation, and pumpI1 is driven in-uniso with machine 4 at a speed proportional to the speed of paper 2 as by being connected by a suitable drive I9 to drive 8.

Except for a very small volume which passes through a friction compensation ypump to be presently described, the entire volume discharged by motor III passes through pump I1 which functions as a meter and thereby controls the stroke of motor IIJ as will presentlyvbe explained. Consequently, pump I6 need supply to motor III only sufcient liquid to compensate for leakage losses,

compressibility of the liquid and deflection dof the parts and-to create the pressure necessary to enable motor I0 to drive, shaft I.

The liquid dischargedby pump I8 in excess of the liquid required by motorv I8 is discharged through a hereinafter described tension control valve 28 which resists the discharge of liquid therethrough and thereby enables pump I8 to supply liquid to motor I0 at the pressure necessary to enable motor I8 to drive winding shaft I.

Pump I6 is supplied with liquid by a gear pump 23 -which is driven in unison therewith and ordinarily arranged in the casing thereof according to the usual practice but which has been shown as being separate therefrom. As shown, gear pump 23 draws liquid from a reservoir 24 and discharges it into a branched supply channel 25 having one branch thereof connected to the stroke control cylinder I3 on motor III and another branch thereof connected to the inlet of a relief valve 26 through which gear pump 23 discharges liquid atv all times into a branched low Y pressure channel 21 having one branch thereof connected to the intake of pump I8.

-Relief valve 28 is adapted to open at a low pressure, for instance 85# per square inch, and it is ofthe type that is unaffected by the pressure at its outlet so that it enables gear pump 23 to maintain in channel 25 a pressure determined by the adjustment of relief valve 28.

The liquid discharged by pump 23 into channel 21 in excess of requirements is exhausted through a relief valve 28 which has its inlet connected to channel 21 and its outlet connected to a drain channel 29 which discharges into reservoir 24. Relief rvalve 28 is adapted to open at a low pressure, for instance 30# per square inch, so as to enable gear pump 23 to maintain in channel 21 a pressure equal to the resistance of relief valve 28.

The operation of motor I8 is under the control of a control valve 33 which is tted in a valve casing 34 and connectedv by a link 35 totion to thereby cause machine 4 to be driven.

Control valve -casing 34 has five annular grooves or ports 38,- 31, 38, 39 and 40 formed in the wall of the bore thereof. Ports 36 and 48 have low pressure channel 21 connected thereto,

port 31 is connected to high pressure channel vI8 by a channel 4I, port 39 is connected by a return channel 42 to the outlet of motor I0, and port 38 is connected to a return channel 43 which may be connected directly to the intake of pump I1 but which has been shown connected to the inlet of .a throttle valve 44 the outlet of which is connected bya channel 45 to the intake of pump I1.

Return channel 42 is also connected to the inlet of a high pressure relief valve 46 which has its outlet connected to low pressure channel 21 and through which motor I8 discharges when valve 33 is shifted to the position shown in Fig. 1

to stop the Winder, relief valve 46 functioning as a brake to stopnotor I0 and winding shaft I smoothly and quickly.

When motor I Il is discharging through brake valve 48, no liquid is returned from motor I8 to pump I1. Therefore, in order that pump I1 may at such time draw liquid from reservoir 24 and in order that gear pump 23 may be used vto initially fill the hydraulic circuit,'drain channel 29 is connected to low pressure channel 21 through a check valvev 41 and low pressure channel 21 is connected through two check valves r48 and 49 to channels I8 and 45 respectively,

fitted in bore 56 and urged downward by yieldable means such as a spring or by iluid pressure, so that the liquid discharged by pumps I6 and I1 in excess of the liquid consumed by motor I0 will flow through bore 56 and channel 51 into reservoir 24, and the iiow through bore 56 will be resisted by valve member 58 which thereby causes pumps I6 and I1 to deliver liquid to motor II) at a pressure proportional to the force exerted upon valve member 58 by the yieldable means.

In order that valve 20 may cause variations in the pressure of the liquid delivered vto motor I to thereby enable motor I0 to exert a greater torque during acceleration of the Winder and/or to vary the tension on the paper in response to lvariations in the speed thereof or to variations in the diameter of roll 3,`valve member 58 is provided with a stem 59 having a plurality of pistons arranged thereon and casing 55 has a plurality of separate cylinders fitted therein sol that the valve may be readily assembled.

As shown, valve stem 59 has two pistons 60 and 6I fixed thereon and tted, respectively, in twoA cylinders 62 and 63 which are closely tted in casing 55 and rigidly secured therein as by cylinder 63 being threadedinto casing 55. Valve A member 58 is continuously urged downward by a helical compression spring 64 arranged in the upper part of cylinder 63 between the upper face of piston 6I and a spring retainer 65 the position of which is determined by an adjusting screw 66 threaded through the upper head of cylinder 63. Turning screw ,66 will vary the tension of spring 64 and thereby :ary the'force required to lift valve member 58 with a resultant variation in the pressure of the liquid delivered to motor I8. Therefore, since the tension of -paper 2 is determined by the torque of motor III and since the torque of motor I0 is determined by the pressure in channel I8, turning screw 66 will vary the ten-` sion of paper 2.

In order to increase the torque of motor I8 during acceleration of the Winder, cylinder 63 is connected at a point below piston 6I with drain channel 61 and at a point above piston 6I to a channel 68 through which gear pump liquid is supplied to cylinder 63 under thecontrol of an acceleration valve 69 which is fitted in a stationary valve casing 10 and has its stem con nected to suitable'operating means such as a lever1l.

'Valve casing 18 has both ends of its bore connected to drain channel 51 and it has two annular grooves or ports 12 and 13formed in the wall' of its bore and connected to gear pump supply channel 25 and channel 68 respectively. When valve 69 is in the position shown in Fig. 1, cylinder 63 is open to drain channel 51 so that piston be created in The arrangement is such that, when accelera-v tion valve 68 is shifted to the position shown in Fig. 3, liquid will flow at a very limited rate through choke 14 which will prevent the pressure in channel 25 from dropping, pressure will the upper end of cylinder 63 and then liquid will flow through relief valve 15 and channels 16 and 51 into reservoir 24, and the liquid in the upper end of cylinder 63 will exert upon piston 6I a force proportional to the resistance of relief valve 15.

The force exerted by-the liquid on piston 6I supplements the force exerted by spring -64, thereby causing the pressure in'channel I8 to increase enough to enable motor I0 to have sufficient additional torque lto accelerate the Winder.

Cylinder 62 has its upper end connected by a channel 11 to channel 43 and its lower end connected by a channel 18 to channel 45 so that,

when throttle valve 44 is adjusted to cause a drop When control valve 33 is in the position shownin Fig. 2 and the drive is in operation, pumps I6 and I1 will deliver liquid to motor I8 and cause it to rotate shaft I to wind paper 2 thereon as fast as it is delivered by machine 4 and, disregarding for the moment'the very small volume which passes through the friction compensation pump to be presently described, all of the liquid discharged by motor I 0 will flowthrough channel 42, valve casing 34,4 channel 43, valve 44 and channel 45 to pump I1 so that motor I0 cannot discharge liquid any faster than it can be consumed by pump I1 which is driven in unison with machine 4 so that the rate at which motor III discharges liquid is proportional to the speed Aof paper 2. a

The liquid discharged by pumpsIB and I1 will tend to drive motor I8 at a speed in excess of the speed required to wind paper 2 upon shaft I as fast as it is delivered by machine 4 but motor I0 cannot wind up paper 2 any faster than it is delivered so that the speed of motor III is determined by the speed of paper 2 and the liquid discharged-by pumps I8 and I1 in excess of motor requirements is exhausted through tension control valve 28' the resistance of which determines lthe pressurein channel I8 and consequently determines the torque of motor III and the tension of paper 2.

In order to maintain constant, the torque of and the speed of motor- 3 increases in diameter.

the tension on paper 2 motor I0 must increase I0 must decrease as roll Since the speed of a hydraulic motor is proportional toits displacement and to the rate at which it discharges liquid, and since the is-proportional to the speed of pump I1 and to the -speed of paper 2 as previously.. explained,

discharge of motor I0 'i varying the displacement of motor III Will also vary the speed of motor I 0. Also, since the torque of a hydraulic motor is proportional to its displacement and to the drop in pressure thereacross and since liquid is supplied to motor III at a pressure which remains constant at any particular setting of tension control valve 20, varying the displacement of motor I0 will vary the motor torque. y

Therefore, a variation in motor torque at any given motor displacement will cause a corresponding variation in the pressure in the return side of the circuit, and these pressure variations are utilized for adjusting the displacement of motor I0. This is accomplished by connecting stroke control cylinder I5 to the return side of the circuit so that the pressure prevailing in lthe return side of the circuit acts upon piston I4 and 'tends to cause it to move slide block II toward the right against the resistance offered by piston I2 which is at all times subjected to gear pump pressure through channel 25.

In order that cylinder I5 may not be subjected to high pressure when motor I0 is discharging through brake valve 46, it is connected to the return side of the circuit at a point beyond control valve 33 as by being connected to return channel 45 through a channel 85 which is also connected through a low pressure relief valve 86 to low pressure channel 21. 'Relief valve 86 protects cylinder I 5 from excessive pressures and provides a. path for the liquid discharged by motor I0 when motor I0 is being operated at a slow speed by liquid supplied only by pump I6 as will presently be explained.

The arrangement is such that, when the drive is in operation, an increase in the diameter of roll 3 due to paper 2 being Wound thereon will cause the speed of motor I0 to lag and the pressure in channels 45 and 85 and in cylinder I5 will drop and permit piston I2 to shift slide block II toward the left to increase the displacement of motor I0 -and thereby simultaneously increase the torque and decrease the speed of motor I0.

In the prior Winder drives, the displacement varying member was shifted in response to pressure variations in the pressure side of the circuit but variation in the slip of the drive caused considerable variation in motor torque with resultant variation in the tension on the paper. By shifting the displacement varying member in response to pressure variation in the return side of the circuit in which there is but little slip due to the low pressure therein, errors in tension due to slip are practically eliminated. In fact,

tests show that such errors are reduced about Another important feature of the present invention is the compensation for the friction in the winding machine and in the hydraulic motor. Tests indicate that this friction is approximately constant at any given tension. When the roll 'is small, the friction is high because of the high speed of the Winder roll. When the roll gets large,- the friction remains equally high because, in maintaining the proper tension, the torque and the bear-ing loads increase at substantially the same rate that thespeed of the roll decreases.

Consequently, at any given tension, the motor forefif no means were provided for compensating for friction, the ldisplacement of motor I0 would be initially adjusted in the above described manner until motor I0' was exerting just suficient torque to overcome the friction and to exert the desired tension on paper 2 and then the displacement and torque will be gradually increased in response to roll 3- increasing in diameter but the torque would not increase at the same rateA that roll 3 increased in diameter.

It therefore follows that, 'in order to maintain the tension on paper 2 at the desired value, slide block II of motor I0 must be shifted by an amount which varies in accordance with variations in the diameter of roll 3 as explained above and, in addition, it must be shifted by an amount side of the circuit during each'revolution of mo-` As shown, a small pump 81 is driven in unison with motor I 0, as by being connected to the shaft thereof by a suitable drive 88, and it has itssintake connected to the return side of the circuit and its outlet connected to low .pressure channel 21. In order to protect pump 81 from high pressure when motor III exhausts through brake valve 46, it is connected to the return side of the circuit at a point beyond control valve 33 as by having its intake connected to channel 43 by a channel 89.

When the drive is in operation, pump 81 extracts liquid from the return side of the circuit and thereby permits piston I2 to moveslide block II toward the left beyond the point to which it Ais moved .in theabove described manner in response topressure variations in the return side of the circuit. The distance that slide block Il is moved in response to operation of pump 81 is just enough to enable motor II) t0 have. just the torque necessary to overcome its own friction and the frictionof the Winder. Thisv increase in motor displacement causes the liquid l discharged by motor I0 to increase by an vamount By thus compensating for friction, the errors in the tension on-the paper due to friction have been practically eliminated. In fact, tests show that such errors have been reduce 87%.

, Pump 81 hasl been shown as being of the variable displacement type so that it may be adjusted when the tension on paper 2 is changed but, where a particular drive is intended to always maintain approximatly the same tension on'the paper, a constant displacement pump is used in actual practice for the reason that it is so much cheaper.

Operation Assuming that paper 2 has been attached to' shaft I, that lever 8 and valves 33 and 69 are in the positions shown in Fig.I 1, that throttle valve 44 is fully open so that it offers no' resistance to the flow of liquid therethrough and that pumps I5 and 23 and. the prime mover which drives transmission 1 are running,` machine 4 and pump I1 will be idle, pump I5 will circulate liquid from -low pressure channel 21 through channels I8 and 4II and valve casing 34 back into channel 21, gear pump 23 will draw liquid from reservoir 24 and discharge it through channel 25, gear pump relief valve 2B, channel 21, low pressure relief valve 5 28 and channel 29 into reservoir 24, the pressure created by gear pump 23 dueto the resistance of relief valve 26 will extend through channel 25 to cylinder I3 and cause piston I2 to move slide block I I toward the left to increase the displacel ment of motor I0 to maximum, and slide block III will cause piston AI4 to expel liquid from cylinder Il5 through channels 85 and 4'5, valve 44, channel 43, valve casing 34, low pressure channel 21, relief valve 28 and channel 28 into reservoir 24.

l5 To start the machine, lever 8 is shifted from the position shown in full lines to the position shown in dotted lines. When it has been shifted approximately half way between these two positions, it will have moved valve 3-3 approximately half way from the positionshown'in Fig. 1 to the position shown in Fig. 2 which is far enough to partly uncover port 39 vand to block communication between ports 31 and 36 but transmission 1 will still be inoperative so that machine 4 and pump I1 will not bestarted until lever 8 is moved farther toward the lposition shown in dotted lines.

Blocking communication between ports 31 and 36 stops pump I6 from discharging into low pressure channel 21 and causes it to deliver liquid through channel I8 lto motor I0 to energize it. Motor 'I0 vbeing at full stroke, it has ample torque to enable it to overcome its own friction and inertia and the friction and inertia of the Winder so that it can readily rotate shaft I to take the slack out of paper 2.

, As soon as' motor I0 starts, the liquid discharged by it will ow through channel 42, valve casing 34, channel 43, valve 44 and'channelsv45 and 85 to cylinder I5 and cause piston I4 to shift slide block IiI toward the right and thereby reduce the displacement of motor vIII to a predetermined minimum and then all 'of the liquid discharged by motor- I8 will lbe exhausted through relief valve 8B into low pressure channel 21 except for 45 a small volume which pump 81 extracts from channel 43 and dischargesinto channel 21, the movement of slide block II toward the right being limited in the usual manner so that at its minimum displacement motor I0 will have sufdcient torque to rotate shaft I.

If there is a considerable amount of slack in paper 2, lever 8-is moved alternately in opposite directions to alternately start and stop motor III so Vthat it will not be driving shaft'l at a. high speed at the instant that the slack is taken up. Ordinarily howeve the amount of slack in paper Zissosmadthatitistakenupduringgradual movement of lever'. from the point at which it causes motor Il to be energized to the point'at 60 which it causes 1 to motion from the prime mover to drive 5. v

Moving lever l to the position shown in dotted lines causes valve 33 to be moved to the position showninlg.2andalsocausesmachine4and l vpump I1 to'bedrlven'at slow speeds. thereby causingmachineltodeliverpaperataslowspeed andpimpHtodischargehquidatarateproportionaltofhespeedofpaperl.,

` Pump Ilwilldrawiissupply of lquidfrom .V channel liandtheby causethe pressure thereinandinchanneltiandmcylinder litndrop andpermitrelietvalvetoelesamazthm. afteralltheliquidbymawrllmnst passthrmlshmmp I1 andthe'ot motor il will be automatically adiusted in reportional sponse to variati-ons in the pressure in the return side of .the circuit as previouslyexplained.

The liquid discharged by pumps I6 and I1 will flow through channel I8 to motor I8 and cause it to drive shaft I to Wind .paper 2 thereon. 5 Due to pump I6, the liquid tends to drive motor I0 faster than the rate required t-o wind up paper 2 as fast as it is delivered by machine 4, thereby causing the pressure to rise and the excess liquid to be discharged through tension control valve 10 20 the resistance of which determines the pres- -sure of the liquid in channel I8 and the torque of mot-or I0.

Pump 81 is driven in unison with motor I0 and extracts a given amount of liquid from the re- 15 turn side yof the circuit during each revolution of motor I0 to increase motor displacement by .the amount necessary to enable motor I0 to have the required amount of torque to cause i't to exert the desired tension on paper 2, 20

Machine 4 may be accelerated to a desired high 4 speed by adjusting transmission 1 or the prime mover that drives it, thereby simultaneously accelerating pump I1 for the reason that itis driven in unison with machine 4 and also causing motor 25 I0 to accelerate and wind y.paper 2 onto roll 3 as fast as it is delivered by machine 4 for the reason that pump I1 regulates the stroke of motor I0 by metering the dis-charge therefrom.

Simultaneouslywith the adjustment of trans- 30 I mission 1 or the prime mover to accelerate inaohine 4, v alve 69 is shifted to the position shown in Fig. 3 to cause in the previously described manner an increase in the resistance of valve 20 and in the pressure lin channel I8 so thatvthe 35 torque of motor III is increased sufficiently t-o enable it to accelerate .shaft Land to maintain the desired tension on'paper 2. As soon as a'cceleratlon ceases, valve 68' isreturned'to the position show-n inv Fig. 1 and then the pressure in channel I8 and the tension on paperv 2 will be determinedby spring 64 the tension of which may be adjusted by turning screw 66. l

As paper 2 accumulates on shaft I, the torque of motor I8 must gradually increase and the speed of motor I0 must gradually decrease in order to maintain a uniform tension on paper 2 for the reason that vpaper 2 is-being delivered at a'uniform linear speed while roll 3 increases in diameter audits rotary speed' decreases relative 5o to its peripheral speed. Y

Since the pressure in channel I8 is constant at any given adjustment of tension control valve 28 and since pump I1 is driven at a speed proto the linear speed of .paper' 2 and 55 meters the outflow from motor III, the decrease in rotary speed will cause'the pressure in the return side of the circuit to drop and permit gear pump pressure acting upon piston I2 to move slide block II toward the left to increase :the displacement of motor .Il with a resultant 60 increase in the torque thereof. Since the increase in roll diameter causes a corresponding decrease in speed, the volumetric out'put of motor liremainsunchanged so that slide block II 65 is moved toward the left at a rate proportional tntherateatlvhichrollBncreasesindiameter' and thereby causes thetorque of'motor Il to increase andthespeed ofmdtor Iltodecrease atthesnmentethatrolllinereasesindiam- 'lo eter. Hotel' llisthusenabledtomaintaia.

uniformtensionupmpaperl The drive E nnnnnlly stopped by gradually the prime mover and adjusting Ifitsdesredtodeleratethe drive at a rapid rate. the desired tension may be maintained on the paper by reducing the torque of motor I0. during rapid deceleration as by the means to be presently described.

If the paper should break or other emergency arise, lever 9 is shifted from the position shown in dotted lines to the position shown in full lines,

thereby stopping the flow o1' .power to machine 4 and simultaneously shifting control valve 33 to the position shown in Fig. l so that port 39 is blocked and port 31 is opened to port 39.v

Machinev 4 will coast to a stop so that pump I1 will continue to deliver liquid until machine 4 comes .to rest and pump I6 will deliver liquid continuously but opening port 31 to port 39 short circuits both pumps and prevents motor I0 from being energized.

Motor IIJ will continue to run due to its inertia and the inertia of roll 3 but'blocking port 39 causes it to discharge through brake valve 49 which resists the discharge of liquid therethrough and thereby decelerates motor I9 quickly and smoothly toa complete stop.

It is sometimes desirable to vary the .tension on paper 2 in response to a variation in speed. For example, it has been found necessary under certain conditions to increase the' torque of the Winder motor as the speed increases in orderto obtain a satisfactory roll of paper due, possibly, to too much clearance in the winding shaft bearings or to curvature of the shaft.

Since .pump I1 is driven in unison with machine 4 and meters the outflow from motor I9 so that the velocity of the liquid in the return side of the circuit is proportional to the linear speed of paper 2, the torque of motor I0 may be varied in response t-o a variation in speed by providing a restriction in the return side of the circuit and causing the resistance of tension control valve 20 to be varied in response .to a variation in the drop in pressure across the restriction.-

As shown, valve 44 when partly closed will cause a slight drop in pressure/thereacross, the pressure in channel 43 will extend through channel 11 t-o the upper end of cylinder 62 and act upon the upper face of piston 60, and the pressure in channel 45 will extend through channel 18 rto the lower end oi' cylinder 92 and act upon the lower face of piston 99 sq' that the downward force exerted upon valve member 59 by spring 54 is augmented by an additional force equal to the difference between the forces exerted by the liquid piston 60 upon opposite Vfaces of piston 69.

An increase in speed will cause the velocity of the liquid in the return side of the circuit to increase and increase the drop in pressure across valve 44 with a resultant increase in the downward force exerted upon valve 59, thereby causing -the pressure in channel I9 to.increase and- The motor torque may be varied at a substantially constan-t rate, a progressively depressing rate, a progressively increasing rate or a combination of such rates by varying theshape of the is subjected to thepressure in chan- This figure shows a valve `44a connected into the returnside of the circuit instead of the throttle valve 44 shown in Fig. y1. Valve44 has a valve member 92 fitted in its casing 93 and urged downward against a stop screw 94by a spring 95 the tension of which is adjusted by means of an adjusting screw 99. An inlet port 91 is formed in the. lower part of casing 93 and connected to channel 43, and an annular outlet port 98 is formed in casing 93 around valve member 92 and .connected to channel 45. Communication between ports 91 and 98 is controlled by valve member 92 which has one or more slots 99 formed in the lower part thereof.

When the drive is in operation, the liquid discharged by motor I0 (Fig. 1) will flow through.

channel 42,*valve casing 34 and channel 43 to liquid will flow through slots 99 to outlet 99 and then through channel 45 to .pump I1.

Valve member 92 will throttle the flow from inlet 91 to outlet 98 and` thereby cause a drop in pressure bet- Ween channels 43 and 45. The pressure in channel 43'will extend through channel 11 to the upper end of cylinder 52 in tension control .valve 20 (Fig. 1) -and the pressure inchannel 45 will extend through channel 19 .to the lower end of cylinder 52 so that valve member 59 is urged downward by an additional force proportional to the difference between thepressures in channels 43 and 45 as previously explained.

As the ow in the return side of the circuit increases in'response to an increase in the speed of themachine, valve member 92 will be raised higher to permit the passage through valve 44* at a faster rate and the resistance it oiers to the increased flow will increase and` thereby increase the drop in pressure across valve 44. with a resultant'increase in the .pressure in channel I9 and the'torque of motor I0 at a rate determined by the shape of slots 99. v

If slots 99 are shaped approximately as shown, the torque of motor I9 will be uniformly increased as the speed increases, but they may be shaped to cause the torque to increase at almost any desired rate either uniform or nonuniform.

v Fic. 5

It is often necessary to gradually vary the tension on the paper in responsev to the roll increasing in diameter in order to produce a roll the .density of which gradually varies from the inside to the outside thereof. One reason tor this requirement is that, under certain conditions, the moisturecontent of the paper changes after the roll is wound and thereby changes the length ofthe paper so'that, by gradually varying the density ofthe roll during the winding thereof, the rollv is of 'uniform density when ready to use.

Since slide block I I is gradually moved toward the leftin response to roll 3 gradually increasing in diameter, a gradual variation in tension may be obtained by increasing theresistance of tension control valve 29 in response to movement oi.' -slide block II. This may beaccomplished by varying the resistance of tension control valve Y20 in response to variation in the drop in pressure across a spring loaded resistance valve the resistance `of which is varied in v response to movement of slide block II,

The drive shown in Fig. 5 is exactly the same 55. is urged downward by a force proportional to the as the drive shown in Fig. 1 except that the liquid discharged by motor I0 ows through a low pressure resistance valve |02 instead of through throttle valve .'44. This requires a slight rearrangement of certain channels which have been indicated by the same'reference numerals with the exponent "a added thereto.

In order to simplify the view, 'resistance valve |02 has been shown attached to stroke control cylinder I5 on motor I0 with its adjusting stem extending through the head thereof into contact with piston I4 so that movement of slide block I I toward'the left will compress the resistance valve spring and thereby increase the resistance of valve |02 but, since this arrangement would require a gland around the adjusting stem, the resistance valve is ordinarily attached to the motor casing with its adjusting stem extending therethrough into vcontact with slide block Resistance valve |02 has been shown as being nonadjustable but in practice an adjustable valve is employed such as by providing means for varying the length of the adjusting stem or providing an adjustable mechanical linkage between the adjusting stem and Aa pinwhich is fastenedv to the slide block and extends through the motor casing.

The'inlet of resistance valve |02 is connected to port 38 in control valve casing 34 by a channel 43 which corresponds with channel 43 and has channel 89 connected thereto, and the outlet of resistance valve |02 is connected to the intake of pump I1 by a channel 45 which corresponds with channel 45. Channels 43u and 45e are connected, respectively, to the upper and lower ends of cylinder 62m tension control valve 20 by two channels 11a and *18* which correspond to channels 11 and 18. Since the other parts are exactly the same as inthe drive shown in Fig. l,

they have been indicated by the same reference numerals and no lfurther'description thereof will be given.

The arrangement is such that,. when the drive is in operation, all of the liquid discharged by motor I0 (except for the very small volume that passes through pump 81) flows through channel 42, valve casing 34, channel 43, resistance valve |02 and channel 45a to the intake of pump i1. Resistance valve |02 will resist the flow of liquid therethrough and cause a drop in pressure between channel 43a and channel 45', the pressure in channel 43e will extend through channel 11.8L to the upper end of cylinder 62 and the pressure in channel 453 will extend through channel 18a to the lower end of cylinder 62 so that piston 60 drop in pressure across resistance valve l |02, thereby increasing the resistance of tension control valve 20 above the resistance determined by.' the tension of spring 64.

When slide block II gradually moves toward the left to gradually increase the displacement of motor l0 in response to roll 3 gradually increasing in diameter as previously explained, it will gradually increase the resistance of resistance-valve |02 and thereby cause the drop in pressure across valve |02 to gradually increase so that the force exerted` upon piston y 60 is gradually increased. Gradually. increasing this force will gradually increase Vthe resistance of valve 2l and the pressure in channel I8 so that the torque of motor Il gradually increases and thereby causes the tension on paper 2 to gradually increase as roll -3 increases in diameter.

If it is desired to gradually decrease the tension on paper 2 as roll '3 increases in diameter, it is simply necessary to reduce the resistance of resistance valve |02 in response to roll 3 increasing in diameter. This may be accomplished by arranging resistance valve |02 on the other side of motor resistance valve shownin Fig. 6, so4 that its l0, as indicated by the v l resistance will be reduced as slide block I moves toward the left.

, Fig. 6

Instead ofvarying the tension on paper 2 as roll 3 increases in diameter by varying the resistance of tension control valve 20 in response to variation in the drop in pressure across a resistancevalve connected into the return pipe of theA `hydraulic circuit as shown in Fig. 5, thesame result may be achieved by varying the resistance of valve 20 in response to variation in the drop in pressure across a resistance valve through which liquid ows from a source other than the hydraulic circuit, such as from gearv pump 23.

As shown in Fig. 6, a low pressure resistance valve |03 is attached to strokecontrol cylinder I3 on motor I0 with its adjusting stem extending through the vheazl thereof into contact with piston I2 so that movement of slide block toward the leftwill permit the resistance valve spring to expand and thereby decrease the resistance of valve |03 but, since this arrangement would require a gland around the adjusting stem, the resistance valve is ordinarily attached to the motor casing with its adjusting stem extending therethrough in-to contact with slide block II. c

Resistance valve |03 has its inlet connected to one end of a channel |04 having the other end thereof connected to gear pump supply channel 25 through a choke |05 which limits the flow of liquid from channel 25 into channel |05 to a very slow rate so that thepressure in channel |04 may be determined by the resistance of resistance valve |03.

The outlet of resistance valve|03 is connected to the lower end of cylinder 62 in tension control valve 20 by a channel I8b which is also connected by channel |06 to drain channel 51, so that the pressure at the outlet'of 'resistance valve |03 and in the lower end of cylinder 62 is substantially zero, and channel |04 is connected to the upper end of cylinder 62 by a channel 11b so that the upper face of piston 60 is subjected to the pressure prevailingin channel |04.

Except for the addition of resistance valve |03, choke |05 and channels |04 and |06, and connecting the upper and lower ends of cylinder 62 tothe inlet and outlet of resistance valve |03 by channels 11b and -18D instead of to channels 43 and 45 by channels 11 and 18, the drive is exactly the same as the drive shown in Fig. l, it being understood that either` throttle valve 44 is fully opened or it is omitted and channel 43 conrected directly to channel 46. Consequently, only a part of the drive has been illustrated and no furtherv description thereof will be given, such parts as are shown being indicated by the same reference numerals that are employed in Fig. 1 toindicate corresponding parts. y

When the drive is in operation, liquid supplied by gear pump 23to channel 25 willflow -at a limited rate through choke- 05, channel and channels 18", |06 Resistance valve |03 liquid therethrough and thereby cause pressure to riseI and extend through channel 11b tothe upper end of cylinder motor l0 to exert a greater torque and maintain upon paper 2 a tension greater than the tension determined by spring 64.

Whenslide block gradually moves toward the left to gradually increase the displacement of motor |0 in response to roll 3 gradually increasing in diameter as previously explained, it

will gradually reduce the resistance of resistance valve |03 and thereby cause the pressure in channels |04 and 11b and in the upper end of cylinder 62 to be gradually reduced so that the force exerted upon piston 60 is gradually reduced. Gradually reducing this force will gradually reduce vthe resistance of valve 20 and the pressure in channel I8 so thatA the torque of motor I0 is gradually reduced and thereby causes the tension on paper 2- to be gradually reduced as roll 3 increases in diameter.

If it is desired to gradually increase the tension on paper 2 as roll 3 increases in diameter, it is simply necessary to increase the resistance of resistance valve |03 in response to rol1'3 increasing in diameter. This may be accomplished by arranging resistance valve |03 on the other side of motor l0, as shown in Fig. 5 by the position of resistance va1ve'|02, so that its resistance will be increasedas slide block moves toward the left. l

N Fig. 7 l

The drive shown in this gure differs from the drive shown in Fig. 6 only in that it' is provided with a diierent tension control valve and the connections thereto are somewhat different.

As shown, the drive is provided with a tension control valve 20*n which is substantially the same as tension control valve 20 except that it has a third piston |0 xed upon its stem 59 between pistons and 6| and fitted in acylinder arranged in casing 55 between cylinder 02 and a cylinder 63 which is the same as cylinder 63 except that it i's shorter.

l Cylinder 62 has channels 11 and 13 connected to the upper and lower lends thereof, respectively, and cylinder 63B has channel 63 connected to the upper end thereof. The upper end of cylinder is connected by a channel 11h to a channel |04 which has one of itsends connected through a choke |05 to gear pump supply channel'25 and its other end connected-to the inlet ofa resistance valve |03 carried by cylinder I3. The outlet of resistance valve |03 is connected to one -end of a channel 18b 'the other end o'f which is connecteddirectly to the lower end of cylinder and through a channel 00* to drain channel 51.

' The arrangement is such that, when the drive is in operation, opposite f ac'es of piston 0l are subjectedto the pressures prevailing upon opposite sides of throttle valve 4.4 (Fig. 1) or valve 44n (Fig. 4) so that the resistance of vtension control valve 208' is varied in response to a variation in the drop in pressure across valve 44 or 44* Idue -to a', variation in speed as previously explained, liquid from gear pump 23 (Fig. 1) 'will flow through channel 25, choke |05, channel |04, resistance valve |03 and channels 18b and |06l into drain channel 51, pressure will extend from channell|04 through channel 11b to the .upper end of cylinder and act upon piston -resiistance of resistance valve |03 to thereby cause motor |0 to gradually varythe tension on paper 2 in response to roll 3 gradually increasing in diameter as previously explained in connection with the description of the drive shown in Fig. 6.

Since the other parts of the drive are exactly the same as the corresponding parts of the drive shown in Fig. 6, like parts have been indicated by like reference numerals and no further description thereof will be given, it .being deemed suilicient to state that, with the drive constructed as shown, the tension on paper 2 will be increased in response to an increase in speed and decreased in response to roll 3 increasing in diameter, that the tension onl paper 2 may be decreased in response to an increase in speed by simply interchanging the connections of channels 11 and 18 to cylinder 62 or to channels 43 and 45, and that the tension on paper 2 may be increasedn response to roll 3 increasing in .diameter by simply attaching resistance valve explained.

Fig. 8

It has previouslybeen explained that motor I0 winds' paper 2 upon the shaft as fast a-s it is delivered by machine 4 so that the speed oi motor I0 is determined by the speed of paper 2, that the pressure of the liquid which energizes motor I0 is constant at any given adjustment of valve 20 so that motor |0 exerts just sufficient torque to rotate shaft and to maintain a given tension upon paper; 2.

Therefore, since the torque required to accelerate a rotating mass is greater than the torque required to keep it rotating, motor I0 must be enabled to exert a greater torque during acceleration in order to maintain the 'desired tension upon paper 2. 'In fact, it has been found that the -paper will sometimes run ahead of "the winding roll unless means are provided for enabling the motor to exert a greater torque during acceleration. l

. Shifting acceleration valve 60 from the position yshownin Fig. 1 to the position shown in Fig. 2 at the beginning of acceleration enables motor I0 to exert a greater torque during acceleration but! the motor torque is increased by a definite amount while the operator may accelerate paper 2 at one rate' at one time4 and at a diierent rate at another time so that there is no assurance that shifting valve 63 will enl tion valve 09-10 and the. connections thereto may be omitted as shown in Fig. 9 and a'n automatic acceleration 'valve |20 may be connected into the return side of the circuit to increase is closely tted in bore |22 substantially constant channels 43 that valve member nel I8 is increased to'thereby enable motor |0 the resistance of tension control valve-20 during acceleration of the paper.`

As shown in Fig. 8, acceleration valve |20 has its mechanism arranged within a casing |2| having a bore |22 and a counterbore |23 formed therein concentric with each other. Bore |22 is connected at its lower end to chan-4 nel 43 and it has an annular groove or port |24 formed in its wall intermediate its ends and connected by a channel |25 to channel 45.

Communication between channel 43 -and port |24 is controlled by a vvalvemember |26 which and provided at its lower end with one or moreslots so that gradual upward movement of valve member |26 will gradually increase the opening between the lower end of bore |22 and port |24.

Valve member |26 is urged downward by a force such, for example, that will require apressure of only about 1 pound per square inch in channel 43 to. raise valve member |26 to open channel 43 to channel 45. While valve member |26 may be urged downward by a spring'which is so soft that its' resistance is not materially increased by compressing it enough to permit valve member `|26 to open channel 43 to channel 45, valve member 46 has been shown provided at its upper end with a weight |21 which is arrangedvin counterbore |23.

In order to delay the opening of valve |20, counterbore |23 is entirely closed except or'a passage |28 which communicates with channel |25 and has a needle valve |29 arranged therein to limit the rate at which liquid may flow therethrough. Valve. |20 has been shown arbutf in practice it is arof the liquid in a reserplify the drawings ranged below the level voir, such as reservoir |23 is lled with liquid at all times.

During normal operation of the drive, valve |20 will cause a slight drop in preure between and 45, the pressure in channel 43 through channel 11 end of cylinder 62- in tension control valve 20 (Fig. 1), and the pressure in channel 45 will extend through channel 18 to the lower end of cylinder 62 so that piston 60 is urged downward by a force proportional to the drop in pressure across valve |20, thereby increasing the resistance of tension control valve 20 above the resistance determined by spring 64 the tension of which is adjusted to compensate for the force exerted upon piston 60. A

When paper 2 is accelerated, the ow in the circuit will increase as previously explained. Since the drop in pressure across an orice varies nearly in proportion to the square of the velocity of the liquid'passing therethrough, an increase in the rate of now will cause a considerable increase in the pressure in channel 43 and this increase in pressure will raise valve member |26 which will expel liquid from counterbore |23 but the escape of liquid from coun-` terbore |23 is retarded by needle valve |20 so |26l must rise very slowly, thereby causing a considerable increase in the pressure in channels 43 and 11 and the upper end of cylinder 82. Increasing the pressure in the upper end of cylinder 62 will increase the downward force exerted'upon piston il and consequently increase the resistance of tension control valve 20 will extend vmotor I0, the pressure deceleration. This may 24, so that counterbore to the upper so that the pressure in than-l to exert sumcient additional torque to accelerate the Winder and to'maintain the desired tension on paper 2. f

` Valve member |26 will continue to slowly move upward during acceleration but the flow will continue to increase so that valve |20 continues -to cause a considerable drop in pressure.

thereacross as long as acceleration continues but, when acceleration ceases, valve member |26 will have been raised high enough to reduce the drop in pressure'across valve |20 to norm-al so that the torque of motor |0.is reduced to normal.

When machine 4 is decelerated without shifting control valve 33 to the position shown in Fig. 1 so as to short circuit pumps I6 and |1 and to apply a brake load to motor I0 as previously explained, the pull of the paper' will decelerate in channel I8 will be maintained at th value determinedv by tension control valve 20 so that motor |0 continues to exert the same pull on the paper, and the inertia of the rotating masses will increase the pull on the paper so that the tension becomes excessive t if' decelation is rapid.

Therefore, in order to maintain the vtension on the paper at' approximately the desired value, the motor torque must be. decreased during rapid be accomplished by increasing the eiect of valve |20 on tension control valve 20 and thenA reducingv thetension of spring 64 to maintain the resistance of tension control valve 20 at thel correct value to enable motor |0 to maintain the desired tension on the paper during normal operation.

The eiect of valve |20 on valve 20 may be increased by increasing the area of piston |50,A so that a small drop in pressure across valve |20 will cause a considerable increase in the resistance of valve 20, or by increasing the drop in pressure across valve l|20 as by using a. larger weight |21 or, if valve member |26 is urged downward by a spring, by increasing the tension of the spring.'

Then when motor I0 is -decelerated, the re sultant decrease in the velocity of the liquid owing through valve |20 will cause a decrease in the drop in pressure across valve |20 and thereby reduce the resistance of tension control valve 20 so that the torque of motor |0 is corre Instead of enabling the'winder motor to exert additional torque during acceleration by vincreasing the resistance of tension control valve 20 in response to manual operation of an acceleration valve as shown in Fig. 1 or in' response to an increase in the drop in pressure across an automatic yacceleration valve as shown in Fig. 8, the torque of the Winder motor may be increased during acceleration and decreased during decel,l eration by varying the resistanceof tensioncontrolvalve 20 inresponse actuated governor which the Winder motor. l

This is accomplished by the drive shown in Fig. 9 which differs from the drive shown in tov operation of a mass' except that it is provided with connected by channel 68 to the wise the same as the drive shown in Fig. 1, likev parts have been indicated by like reference numerals and no further description thereof will be given.

Due to the mass actuated governor, the shaft |3| (Fig. 10) of motor l08l is longer than the shaft of motor I and is supported in a bearing |32 carried by a special end head |33 .which is attached to the motor casing |34 and closed at its inner end by plate |35 having formed therein an opening |36 through which liquid may escape from the interior of end head |33 into the interior of casing |34.

Shaft |3| extends through a two piece gland |31 which is attached to end head 33 and has a groove |38 formed therein around shaft |3|, suitable packing |39 and |40 being provided to prevent the escape of liquid from groove |30 through the ends of gland |31.

Groove |38 is connected by a channel |4| to one end of a channel |42 (Fig. 9) which is connected at its other end to the outlet of a' choke |43 and isv connected intermediate its ends by a channel 6B to the upper end of cylinder 63 in tension control valve 20. 'I'he inlet of choke |43 is connected 'to gear pump supply channel 25 so that liquid may flow from gear pump 23 through .channel 25, choke`|43 and channels 42 and |4| to 'groove |38 at a very limited rate as determined by choke |43, and the pressure created in channel |42 by the mass actuated governor to be presently described will extendthrough channel 68B to the upper end of cylinder 63 and urge piston 6| downward to increase the resistance of tension control valve 20.

` Shaft |3| (Fig. 10) has formed therein a passage |44 which extends radially inward from groove |38, then longitudinally of shaft 3| and then' radially outward into communication with one end of a passage |45 (Fig. l1) formed in an impeller |46 which is xed, as by means of a key |41, upon shaft |3| and has opposed slots-|48 and |49 extending inward from the periphery thereof.

The other end of passage |45 communicates with a bore |50 which is formed in impeller |46 and has one of its ends closed andits other end opening into slot |48. Bore |50 contains a valve having two pistons |52 uponopposite ends thereof. Piston |52 controls communication between bore |50 and slot |48 and thereby regulates'the rate at which liquid may escape from bore 50 into end head |33. Piston |53 `has formed therein a small groove |54 through which liquid may iiow toI the closed end of bore 50 and act upon piston |53 so that valve |5|, is urged outward or in a direction to open bore |50 to slot |48 by the pressure prevailing in passage |45.

The outer end of valve |5| arranged in slot |48 and xed which is rotatably supported concentric with shaft 3| as by means of a ball bearing |51 carried by the hub of impeller |46. 'Ihe arrangement is suchl that ny 'wheel |56 is rotated solely engages a lug |55 to a y wheel |56 by a channel 68a two diametrically and |53 arrangedv 2,232,317 Fig. l only in that the manually operated acby the force transmitted thereto through valve |5| when impeller |46 is rotated.

In order to hold lug |55 in contact with piston |52 during -normal operation of the Winder motor and to decrease the motor torque during deceleration, fly wheel 56 has a lug |58 xed thereto and extending into slot |49. Lug |58 engages a plunger |59 arranged in a bore |60 which is formed in impeller |46 and contains a spring |6| to urge plunger |59 toward lug 58, movement of plunger |59 in that direction being limited by suitable shoulders formed upon plunger |59 and around the end of bore |60.

When the drive is' in operation, liquid will ow from gear pump 23 (Fig. 9) through channel 25, choke 43, channels |42 and'|4| (Fig. 10), groove |38, passages |44 and |45 (Fig. 11) and bore |50 into end head |33 at a very limited rate as determined by choke |43. The liquid may escape from end head 33 through opening |36 into motor casing |34 from which it is drained to a reservoir in the usual manner.

vIf it is desired to reduce the motor torque rangedthat lug |55 holds piston |52 close enough to the end of bore |50 to cause it to throttle the ow of liquid.' therefrom and thereby cause pressure to rise in channel 42 and extend through channel 688- to cylinder 63. Since this pressure will act upon piston 6| and thereby increase the resistance of tension control valve 20, the tension of spring 64 is correspondingly reduced so that the resistance of valve 20 will be just suiicient to enable motor |0a to maintain the desired tension on the paper during normal operation.

When motor l0'L ,is started or accelerated, impeller |46 will startior accelerate as it is fixed to shaft 3| but, since flywheel |56 is rotatably supported upon the hub of impeller |46, its inertia will cause it to lag behind impeller |46 and move valve |5| into bore |50 to. increase the throttling effect of piston 52 and thereby cause the pressure in the channels between bore |50 and choke |43 to rise and increase the resistance of tension control valve 20 so that motor I0a is enabled to exert a greater torque as previously explained. Y The faster motor I0a greater the force iiywheel |56 so that the force transmitted from impeller |46 through valve 5| to fly wheel |56 will -be approximately proportional to the rate of acceleration. Since the pressure in channel |45 will increase in proportion to the increase in the force transmitted through valve |5|, the resisttance of tension control valve 20 and consequently the. torque of motor |01l will increase approximately in proportion to the rate of acceleration so that motor loa is able to maintain the desired tension on paper 2 regardless ofthe rate at which it is accelerated.

When motor I0B is decelerated, impeller |46 wil be deceleratei with it due to being fastened to shaft |3| .but iiywheel |56 must be decelerated through the contact of lug |58 with plunger |59. The energy stored in flywheel |56 will cause lug |58 to move plunger |59 into bore |60 against the resistance of spring 6| and thereby cause lug |55 to move away from the end of bore 50 and permit the liquid in the inner end of bore |50 to move valve |5| outward to reduce the throttling eiect of piston 52 so that the pressure in the channels between bore |50 and choke 43 is reduced. This reduction in pressure wilt starts or accelerates the required to start or accelerate for causing said of tension control valve 20 and thereby reduce the torque of motor l* by an amount sumcient to compensate for the inertia of the rotating masses so that the tension on the paper is maintained at approximately the desired value as previously explained.

Since the drive otherwise operates in exactly the same manner as the drive shown in Fig. 1, no the operation thereof will further explanation of be given. It is deemed sufficient to state that the tension on the paper may be varied in response to variations in speed by partly closing throttle valve 44 or by substituting valve e for valve BI as shown in Fig. 4, that the tension on the paper may be varied in response to the roll of paper increasing in diameter as shown in Fig. or Fig. 6, and that the tension on the paper may be varied in response both to variations in speed and to variations in roll diameter by combining the circuits -as shown in Fig. '1.v The invention is susceptible of othervmodications and adaptations without departing from the scope thereof as hereafter claimed.

The invention is hereby claimed as follows:

l. The combination, With a machine from which sheet material is delivered at a speed proportional to the speed of said machine and a Winder for Winding said sheetinto a roll, of a variable displacement hydraulic motor for driving said Winder .and maintaining tension upon said sheet, a metering pump driven in unisonwith said machine for supplying liquid tosaid motor and for controllingthe rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith .a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a'tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, and' means for varying the' displacement of said motor in response rto variations in' the pressure in the return side of said circuit.

2. The combination, with a machine from which sheet material is delivered at a speed proportional to the speed of said machine and a Winder for Winding said sheet into a roll, of a variable displacement hydraulic motor for driv` ing said Winder and maintaining tension .upon said sheet, a metering pump driven in unison withv said machine for supplying liquid to said motor and for controlling `the rate at which liquid can be discharged therefrom, channel means connecting said pump .and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return side of said circuit, and means motor to vary the tension o n said sheet in response to variation in the speed of said sheet.

3. The combinatiom vwith a machine from which sheet material isdelivered at a speed proportional to the speed' of said machine and a Winder for winding said sheet into a roll, of a variable displacement hydraulic motor for driving said Winder and maintaining tension upon said sheet, a metering pump driven-in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting lsaid pump and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit lto thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permitliquid to escape therefrom after the pressure thereinexceeds the resistance. of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return Iside of said circuit, and

means for causing said motor to vary the tension on said sheet in response to said roll increasing in diameter.

4. The combination, with speed proportional to the speed of said machine and a Winder for winding said sheet into a roll, of a a machine from variable displacement hydraulic motor for drivy ingl said Winder and maintaining tension upon said sheet, a metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid canbe discharged therefrom, channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension con. trol valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said vaive,'means for varying the displacement of said the tension on said sheet.

5, The combination, with a machine from which sheet material is delivered at a speed proportional to the speed of said machine-and a Winder for winding said sheet into a. roll, of a variable displacement hydraulic motor for driving said Winder` and maintaining tension upon said sheet, a metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressureside of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return side of said circuit, and means for varying the 4resistance of said tension control valve in response to said roll increasing in diam- 1 portional to the speed of said machine and a Winder for winding said sheetl into a roll, of a variable displacement hydraulic motor for driving said Winder and maintaining tension upon said sheet, a' metering pump driven; in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the` pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return side of said circuit whereby motor displacement is increased and motor speed is decreased as said roll increases in diameter,

vand a third pump driven in unisonfwith said motor for extracting a small volume of liquid from the return side of said circuit during each revolution of said motor to thereby cause said displacement varying means to increase the. displacement of said motor by the amount necessary to enable said motor to have enough torque to overcome its own friction and the friction of said Winder.`

7. The combination, with a machine from which sheet material is delivered at a speed proportional to the speed of said machineand a Winder for winding said sheet into a roll, of a variable displacement hydraulic motorfor driving said Winder and maintaining tension upon said sheet, a metering pump driven in unison' with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming' therewith a hydraulic circuit having pressure and return sides, an independently .driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension controlvalve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of saidvalve, means for varying the displacementof said motor in response to variations in the pressure in the return side of said circuit whereby motor displacement is increased and motor speed is decreased as said roll increases in'diametenf a third pump driven in unison with said motor for extracting a small volume of liquid from the return side of said circuit during each revolution of saidmotor to thereby cause said displacement varying means to `increase the displacement of said motor by the amount necessary to enable -said motor to havefenou'gh torque to overcome its own friction and the friction of said Winder, and means for causing said motor to vary the tension on said sheet in response to said roll increasing in diameter.

48. The combination, with a `machine fromwhich sheet material is delivered at a speed pro portional to the speed of said 'machine and a Winder for winding said sheet intoaroll, of a variable displacement hydraulic -motor for driving said Winder and maintaining tension upon`Y lsaid sheet, a' metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid ance of said tension control valve in response to can be discharged therefrom. channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure Y and return sides, an independently driven booster pump for delivering liquid into the pressure side 5 of said circuit to' thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of 10v said valve, means for varying the displacement of said motor in response to variations in the pressure in the return side of said circuit whereby motor displacement is increased and motor speed is decreased as said roll increases in diama variation in the -speed of said sheet to thereby cause said motor to varyV the tension on said sheet. I

9.` The combination, with a machine from which sheet material is delivered at a speed proportional to the speed of said machine and a Winder for winding said sheet into a roll, of a variable displacement hydraulic motor for driving said Winder and maintaining tension upon said sheet, a. metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liql uid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure and return sides, an independently driven booster lpump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tensioncontrol valve connected to the pressureside of said 45 circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of sure in the return side of motor displacement is increased and motor speed is decreased as said roll increases in diametena third pump driven in unison with said motor forl extracting a small volume of liquid from the re-v y turn side of said circuit during' each revolution 5 of said motor to thereby cause said displacement varying means to increase the lacement of said motor by the amount 'n y to enable' said motor to have enough torque to overcome its own friction and the friction of said Winder, ,50 and means for varying the vresistance of saiif/ tension control valve in response tosaid roll increasing in diameter to thereby cause said'motor Vto vary the tension on said sheet.

which sheet material is delivered 'at a speed y:iro-

portional to the speed of said machine and a Winder Yfor windingsaid sheet into va. roll. fof a. variable displacement hydraulic motor for driving said Winder and maintaining tension upon V-70 said sheet, a metering pump driven in unison with said machine-for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump 4and. saidJnotor and form 'l5 `ing .therewith a. hydraulic circuit having pressure -third pump driven in unison with said motor for parts of said return side whereby said drop in pressure will vary in response to variation in the velocity of liquid in said return side caused by variation in the speed of said sheet, and means responsive to variations in said drop in pressure for varying the tension on said sheet.

11. The combination, with a. machine from which sheet material is delivered ata speed proportional to the speed of said' machine and a Winder for Winding said sheet into a roll, of a variable displacement hydraulic motor for driving said Winder and maintaining tension upon' said' sheet, 'a metering pump drivenin unison withl said machine for supplying liquid to said motor and for controlling the rate at which liquid can be dischargedl therefrom, channel means connecting 'said pump and said motor and form- 4ing therewith a hydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into thepressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tens-ion control valve connected to the pressure side of said circuit to permit liquid to escape therefrom aftery the pressure therein exceeds the resistance ofsaid valve, means'for varyingthe displacement of said. motor in response to variations i'n the pressure in the return side of said circuit, throt- 1 tling means arranged in the return side of said l es circuit to' causea drop in pressure between two parts'oi' said return side whereby said drop in pressure will vary in response to variation in the' velocity or liquid in said return side caused' by variation in the speed of said sheet, and means responsive to variations in said drop in pressure for varying the resistance of lsaid tension control valve to thereby cause said4 motor to vary the tension on said sheet.

12'. The combination, With a machine `fro-m which sheet materialjis delivered ata speed proportional to .the speed of said machine and a Winder forwinding said sheet into a roll, of a variable displacement hydraulic motor for driving said Winder and maintaining tension upon said sheet, a metering 'pump driven in unison with said'maclriinefor supplying liquid to said motor and for controlling the rate at which liquid therewith a hydraulic circuit having pressure and 'return sides,

an independently driven booster pump for delivering liquid into the pressure side of said circuitv to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds theV resistance of said valve, means for'varyirig the displacement,

of said motor in response to variations in the pressure in the return sideof said circuit whereby motor dis-placement is increased and motor speed is decreased as said roll increases in diameter, a

.increase the displacement thereof,

`by a' machine, comprising extracting a small volume of liquid ,from the return side of said circuit during each revolution of said motor to thereby cause said displacement varying .means to increase the displacement of said `motor by the amount necessary to enable said motor to have enough torque to overcome its own friction and the friction o-f said Winder,

Athrottling means arranged in the return side 'of said circuit to cause a drop in pressure between two parts of said return side whereby said drop in pressure will vary inv responseto variation in proportional to the speed of said machine and a Winder for winding said sheet into a roll, of a Variable displacement hydraulic motor for driv-y ing said Winder and maintaining tension upon said sheet, a metering pump driven in unison with Asaid machine for supplying liquid to said motor and for controllingthe rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith a hydraulic circuit having pressure and re-- turn sides, an independently driven booster pump for delivering liquid into the pressure side of l.said circuit to.. th`ereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return sideqof said circuit whereby motor displacement is increased and motor speedis decreased as said roll increases in diameter, a third pump driven in unison with said motor for extracting a small volume of liquid from the return side of said circuit during each revolution of y said motor to thereby cause said displacement varying means to increase the displacement of saidmotor by the amount necessary'to enable said motor to have enough torque to overcome its own friction and the friction of said Winder, throttling means arranged in the return side of said circuit to cause a drop in pressure between two parts of .said return side whereby said drop in pressure will vary in response to Variation in the velocity of liquid in said return side caused speed of said sheet, and means responsive to variations in said drop in pressure for varying the resistance of said tension control valve to thereby cause said motor to vary the tension on said sheet. 14; A drive, for driving a Winder which Winds by a machine, comprising a variable displacement'hydraulic motor for driving said Winder and maintaining tension upon said sheet, means -for supplying motive liquid to said motor to energize the same, means operated in response to said roll increasing in diameter for adjusting said motor to and means operated in response to operation of said motor adjusting means for varying the torque of said motor to thereby vary the tension on said sheet.

15. A drive; for driving a Winder which Winds sheet material into a roll as ihis delivered thereto a variable displacement hydraulic motor for driving said Winder and maintaining tension upon'said sheet, means for supplying motive liquid to said motor to energize by Variation in the valve, means for '5 diameter.

the same, means operated in response to said'roll increasing in diameter for adjusting said motor to increase the displacement thereof, a resistance directing liquid through said resistance valve, means for varying the torque of fsaid motor in response to a drop in pressure across Y supplying motive liquid to said motor to energize maintaining celerated for increasing the torque of said motor motor adjusting the same, means operated in response to said roll increasing in diameter for adjusting said motor to increase the displacement thereof, and means for increasing the torque of said motor during acceleration thereof without affecting the operation of saidmotorvadiusting means.

17. A drive, for driving a Winder which winds sheet material into a roll as it is delivered thereto by a, machine, comprising a variable displacement hydraulic motor for driving said Winder and tension upon said sheet, means for supplying vmotive liquid to said motor to energize the same, means operated in response to said roll increasing in diameter for adjusting said motor to increase the displacement thereof, and means responsive to said motor being accelerated for increasing the torque of said motor during acceleration without affecting the operation of said motor adjusting means.

18. A drivefor driving a Winder which Winds sheet material into a roll as it is delivered thereto by a machine, comprising a variable displacement hydraulic motor for driving said Winder and maintaining tension upon said sheet, means for supplying motive liquid to said motor to energize the same, means operated in response to said roll increasing in diameter for adjusting said motor to increase the displacement thereof,v and means responsive to said motor being accelerated or deduring accelerationand decreasing it during deceleration Without affecting the operation means.

l19. A drive, for driving a Winder which winds sheet material into a roll as it is delivered thereto by a machine, comprising a variable displacement 'hydraulic motor for driving said Winder and maintainingl tension upon said sheet, pumping means for supplying rate in excess of motor requirements, channelv means connecting said pumping means to said motor and forming therewith a hydraulic circuit4 having pressure and return sides, a tension control valve connected to the pressure side oi' said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, and means responsive to said motor being acceleratedA for increasing the resistance of said valve during acceleration. 20. A drive, for driving a Winder which Winds sheet material into a roll asit is delivered thereto hydraulic" motor for driving said Winder and maintaining tension upon said sheet. pumping means for .supplying liquid to said motor at a.

rate in excess of motor requirements, channel of said liquid to said motor at al means connecting said pumping l'means to said motor and forming therewith a hydraulic circuit having pressure and return sides, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve,

and means responsive to said motor being accelerated or decelerated for increasing said sheet, a metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump and said motor and forming therewith ahydraulic circuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure.side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom after the pressure therein exceeds the resistance of said valve, means for varying the displacement of said motor in response to variations in the pressure in the return side of said circuit, means for causing said motor'to vary the tension on said sheet in response to variation in the speed oi' said sheet, and means vfor causing said motor to vary the tension on said roll increasing in diameter.

22. The combination, with a machine from which sheet material is delivered at a speed proportional Atcl the speedl oi' said machine and a Winder forV winding said sheet into a roll, of a variable displacement hydraulic motor for driving said Winder and said sheet, a metering pump driven in unison with said machine for supplying liquid to said motor and for controlling the rate at which liquid can be discharged therefrom, channel means connecting said pump and -said motor and forming therewith a hydraulic lcircuit having pressure and return sides, an independently driven booster pump for delivering liquid into the pressure side of said circuit to thereby provide liquid in excess of the requirements of said motor, a tension control valve connected to the pressure side of said circuit to permit liquid to escape therefrom' after the pressure therein exceeds the resistance oi' said valve, means for varying the displacement of said motor in response to variations in the pressure material is delivered ata speed pro-' maintaining tension uponV in the returnside of said circuit whereby motor f displacement is increased and motor speed is decreased as said roll increases in diameter, a

q its own friction and the friction of said Winder, by a machine, comprising a variable displacement JAL/msx. DOUGLAS.

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